Year : 2017 | Volume
: 7 | Issue : 4 | Page : 107--131
1st IBRO-APRC Banasthali School of Neuroscience
|How to cite this article:|
. 1st IBRO-APRC Banasthali School of Neuroscience.Int J Nutr Pharmacol Neurol Dis 2017;7:107-131
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. 1st IBRO-APRC Banasthali School of Neuroscience. Int J Nutr Pharmacol Neurol Dis [serial online] 2017 [cited 2020 Sep 26 ];7:107-131
Available from: http://www.ijnpnd.com/text.asp?2017/7/4/107/217557
Neurodegeneration and Neuroinflammation: Molecular Basis to Pathogenesis and Management
Organized by: Department of Pharmacy, Banasthali University, Banasthali - 304 022, Rajasthan, India
21–26 August 2017
IBRO-APRC Banasthali School Convener
Prof. Sarvesh Paliwal
IBRO-APRC Banasthali School Organizing Secretary
Dr. Vivek Jain
Drug Development for Obesity and Diabetes: Why Brain Matters
Zydus Research Centre, Ahmedabad, Gujarat, India
Address for correspondence: Dr. Amit Johrapurkar, Zydus Research Centre, Ahmedabad, Gujarat, India.
Metabolic syndrome is a disorder comprising obesity, type 2 diabetes, and dyslipidemia. Together, these deadly diseases increase morbidity and mortality due to cardiovascular complications. Many new pharmacological agents that target weight loss and improve glycemic control can improve cardiovascular outcomes. However, these agents also induce a range of metabolic, cognitive, and behavioral changes that may affect their utility over time. Characterizing the “side effects” induced by such agents due to their actions in the central nervous system is very crucial in preclinical and clinical drug discovery. Preclinical and clinical biomarkers for these mechanisms need to be used to understand the safety margin of the investigational drugs. This presentation examines two pharmacological approaches, namely GLP-1 agonists and cannabinoid receptor 1 antagonists, for their central and peripheral effects.
Histone Acetylation or Deacetylation in Neuropathic Pain: A Double-Edged Sword?
Amteshwar Singh Jaggi
Pharmacology Division, Department of Pharmaceutical Sciences & Drug Research, Punjabi University, Patiala, Punjab, India
Address for correspondence: Dr. Amteshwar Singh Jaggi, Pharmacology Division, Department of Pharmaceutical Sciences & Drug Research, Punjabi University, Patiala, Punjab, India.
Chronic pain is broadly classified into somatic, visceral or neuropathic pain depending upon the location and extent of pain perception. There are a number of mechanisms considered to be responsible for induction of pain resulting from nerve or tissue damage that may develop into unrelenting pain state. Evidences from different animal studies suggest that inflammatory or neuropathic pain is associated with altered acetylation and deacetylation of histone proteins, which result in abnormal transcription of nociceptive processing genes. There have been a number of studies indicating that nerve injury up-regulates histone deacetylase enzymes, which leads to increased histone deacetylation and induces chronic pain. Treatment with histone deacetylase inhibitors relieves pain by normalizing nerve injury-induced down-regulation of metabotropic glutamate receptors, glutamate transporters, glutamic acid decarboxylase 65, neuron restrictive silencer factor and serum and glucocorticoid inducible kinase 1. On the other hand, studies also refer to an increased expression of histone acetylase enzymes in response to nerve injury that promotes histone acetylation leading to pain induction. Treatment with histone acetyltransferase inhibitors has been reported to relieve chronic pain by blocking the up-regulation of chemokines and cyclooxygenase-2, the critical factors associated with histone acetylation-induced pain. It suggests the dual role of histone acetylation/deacetylation in the development or attenuation of neuropathic pain with unresolved issues.
Deregulation of Transcriptionally Repressive Histone Lysine Methylation-Based Epigenetic Mechanisms Leads to Depression and Related Psychiatric Disorders
CSIR – Centre for Cellular and Molecular Biology (CCMB), Hyderabad, Telangana, India
Address for correspondence: Prof. Arvind Kumar, CSIR – Centre for Cellular and Molecular Biology (CCMB), Hyderabad, Telangana, India.
The complex nature of psychiatric disorders has been quite challenging for neuroscientists to uncover the underlying molecular mechanisms. However, the intense research in recent years suggests deregulation of critical epigenetic regulatory mechanisms in the onset as well as maintenance of depression, anxiety, and related emotional or affective disorders. Our research efforts in this direction appear to conclude that repeated perturbations to the nervous system start affecting the function of critical genes that control the proper functioning of neural circuitries, by deregulating transcriptionally repressive epigenetic modifications, histone H3K9 and K27 demethylation. Using chronic social defeat stress (CSDS) induced depression model in mice, we have shown how repeated defeat stress results in molecular changes in reward and cognitive pathways, thus inducing anhedonia, the hallmarks of depression, by increasing repressive H3K9 and K27 dimethylation. A number of lysine methyltransferases and lysine demethylases (KDMs) that regulate these two critical repressive epigenetic marks also have been found deregulated by us in critical neural substrates of these circuitries, nucleus accumbens (NAc) and hippocampal dentate gyrus (DG) respectively, which are implicated in affective disorders. The interesting findings on the role of Jumonji-domain-containing demethylases of KDM4 and KDM7 families in neural, behavioral, and neurogenic changes gave us not only better insights into the etiopathology but also a strategy to treat depression by modulating KDMs.
Our lab has also identified a novel KDM7 family member that appears to act on H3K9me2, H3K4me3, and few other H3 and H4 lysine methylations. The level of this novel demethylase was differentially regulated in reward circuitry following CSDS, and its overexpression in NAc using intracranial adeno-associated virus injection could induce depression-like condition in mice even in the absence of any stress exposure. The chromatin immunoprecipitation and next-generation sequencing approach have led us to identify hundreds of gene targets of this novel KDM7 family member in Neuro2A cells. After validation of a few of its targets and further experiments showed us how this novel demethylase induces alterations in spine morphology, spine density, and synaptic plasticity, as well as the characteristics observed in NAc, that is, the critical neural substrate of the reward circuitry, in depression.
Chronic stress, depression, anxiety, and related mood disorders as well as cognitive disorders are associated with significant attenuation in adult neurogenesis in the hippocampal DG, the dynamic region of the cognitive circuitry. The proliferation of neural stem/progenitor cells gets severely affected, causing attenuation in the turnover of mature healthy neurons in the hippocampus. Using CSDS model, we have also uncovered the critical role KDM4 family demethylases play in transducing chronic stress effects on DG neurogenesis, hippocampal remodeling and neural and behavioral plasticity leading to mood and cognitive disorder phenotype. Thus, the molecular insights into the functioning of these two diverse families of epigenetic regulators have translational implication too, in addition to their role in etiopathology.
Sigma Receptor Ligands: From Discovery to Clinical Translation
Christopher R. McCurdy
Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida, USA
Address for correspondence: Prof. Christopher R. McCurdy, Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville 32610, Florida, USA.
Peripheral nerve injury, as a consequence of trauma, surgery, inflammation, or other causes, is a major medical problem. This type of injury is often associated with chronic pain. About 100 million people suffer from chronic pain in the United States alone. Diagnosis and treatment are still considered as unmet medical needs. Current clinical imaging methods used to evaluate chronic pain are centered on anatomic alterations, which do not necessarily reflect the origin of chronic pain. A potential biomarker associated with nerve injury and neuroinflammation is the sigma-1 receptor (S1R). In addition, S1Rs appear to play an active role in pain modulation, both peripherally and centrally. We recently identified a highly selective S1R antagonist that was transformed into a PET probe candidate and demonstrated high specificity and selectivity for imaging S1Rs in mice, rats, and monkeys. We have utilized this probe in a rat model of nerve injury via PET/MRI. The results have helped promote the clinical use of the agent in identifying peripheral pain generators in patients suffering from neuropathic pain. Furthermore, we have investigated the cold compound and similar derivatives as potential pharmacotherapies for neuropathic pain in mouse models of nerve injury. These compounds have equipotent or superior analgesic efficacy to the clinically utilized gabapentin. The compounds have also been examined for liabilities in locomotor, rotorod, conditioned place preference, and in some cases, self-administration assays. The results indicate that the analgesic effects produced by S1Rs antagonists are not associated with these potential liabilities. These results confirm the ability of S1Rs to serve as potential diagnostic and analgesic agents for neuropathic pain without CNS liabilities.
Funding was provided by NIDA (DA023205), NIGMS (GM104932), US Department of Defense, the Center for Biomedical Imaging at Stanford University, and the State of Florida, Executive Office of the Governor’s Office of Tourism, Trade, and Economic Development.
Neurobehavioral and Neurochemical Aberrations in Parkinson’s Disease and its Treatment With Thymoquinone
Fakhrul Islam, Mohammed M. Safhi, M. M. Khan1
Department of Pharmacology, Toxicology College of Pharmacy, Jazan University, Jazan, Saudi Arabia, 1Department of Neurology, University of Tennessee Health Science Center, Memphis, TN, USA
Address for correspondence: Dr. Fakhrul Islam, Department of Pharmacology and Toxicology, College of Pharmacy, Jazan University, Jazan, Saudi Arabia.
Parkinson’s disease (PD) is a degenerative disorder of the central nervous system that often impairs the sufferer’s motor skills and speech. The disease is characterized by a progressive degeneration of dopaminergic neuron in the SNpc leading to dopamine depletion. The primary symptoms of the disease are tremor, rigidity, bradykinesia/akinesia, and postural instability. Male Wistar rats were divided into four groups. Group-1 was PD, and 6-hydroxydopamine (6-OHDA) was injected in the striatum. Group-2 was sham, and it was treated in the same way as PD but in the place of 6-OHDA, saline was injected in the striatum. Group-3 was 6-OHDA (for 3 weeks) followed by thymoquinone (TQ) for 2 weeks, and group 4 was sham treated with TQ for 2 weeks. Animals were sacrificed just after 5 weeks. The behavior activities were checked a day before sacrificing the animals, which were decreased in the PD group and were protected significantly with the treatment of TQ. The brains were taken out quickly to dissect the striatum. The increased level of lipid peroxidation and decreased content of glutathione were protected significantly with the treatment of TQ. The activities of antioxidant enzymes (glutathione peroxidase, glutathione reductase, superoxide dismutase, and catalase) were decreased significantly, which were protected significantly with the treatment of TQ. The decreased activities of phospholipase A2, poly-ADP-ribosyl polymerase, caspase-3, and Na+K+-ATPase were protected significantly with the treatment of TQ. The decreased contents of dopamine, 3,4-dihydroxyphenyl acetic acid, and dopamine D2 receptors were also protected significantly with the treatment of TQ. The expressions of Cox, inducible nitric oxide synthase (iNOS), p53, and tyrosine hydroxylase were protected significantly with the treatment of TQ. The contents of TNF-α and IL-1β and fragmentation of Deoxyribonucleic acid (DNA) in the PD group were also protected significantly with the treatment of TQ as compared to the sham group. The TQ has protected the biomarkers of PD in a 6-OHDA animal model.
Therapeutic Targets for Neurodegeneration From Natural Molecules
Musthafa Mohamed Essa, Samir Al-Adawi
Department of Food Science and Nutrition, CAMS, Sultan Qaboos University, Oman
Address for correspondence: Dr. Musthafa Mohamed Essa, Department of Food Science and Nutrition, CAMS, Sultan Qaboos University, Oman.
Oxidative damage and neuroinflammation are the two main offenders that play an important role in the pathogenesis of neurodegenerative diseases (NDDs) including Parkinson’s disease (PD). Studies showed that naturally occurring antioxidants found in fruits, vegetables, herbs, and nuts, could potentially delay neurodegeneration, and improve cognition and memory. Changes in the behavior, biochemical indices, and protein expression patterns of oxidative/inflammatory markers occurred during NDDs. The current preventive measures are very expensive and not long lasting. Therefore, the need to find intervention strategies using natural antioxidants is of supreme importance. A diet rich in natural antioxidants might influence the risk of brain function and health. The exact mechanism of action behind the benefits of natural antioxidants is due to the action of these phytonutrients on diverse signaling pathways associated with the oxidation of macromolecules and inflammation. These bioactive natural antioxidants/nutrients could be able to play a vital role in delaying the progression of various NDDs such as PD (Parkinson disease). The benefit of natural antioxidants on cognition, memory, oxidative stress, and inflammation in NDDs including PD-like conditions is discussed here with the support of work from our lab. This work was supported by an internal grant from CAMS, SQU, Oman (IG/AGR/FOOD/17/02) and is highly acknowledged.
Neuroinflammatory Pathways and Therapeutic Strategies in Dementia of Alzheimer’s Disease
Pharmacology Division, Department of Pharmaceutical Sciences & Drug Research, Punjabi University, Patiala, Punjab, India
Address for correspondence: Prof. Nirmal Singh, Pharmacology Division, Department of Pharmaceutical Sciences & Drug Research, Punjabi University, Patiala, Punjab, India.
Dementia is a chronic condition characterized by a progressive cognitive impairment that leads to functional disability. In 2015, it was estimated that approximately 47 million people worldwide were affected by dementia, and this number is expected to increase, reaching 131.5 million by 2050. Alzheimer’s disease (AD) accounts for approximately 60–80% of all dementia cases. AD is a multifaceted neurodegenerative disorder, with aging, as well as genetic and environmental factors contributing to its occurrence and advancement. AD has affected more than 37 million people worldwide, and the economic burden in the US alone is estimated to be around $100 billion. Given this evidence, it is clear that dementia represents one of the greatest global public health challenges. The characteristic histopathological hallmarks of AD include extracellular amyloid plaques and intracellular neurofibrillary tangles composed of amyloid peptides (Aβ) and hyperphosphorylated protein “tau,” respectively. The generation of Aβ requires sequential cleavage of amyloid precursor protein (APP) by β- and γ-secretase, respectively. An optional initial cleavage of APP by α-secretase precludes subsequent Aβ formation. It has become evident that AD is also associated with chronic inflammation and dysregulated lipid homeostasis within the diseased brain. Studies have revealed that AD patients display excessive neuronal loss/dystrophy and a prominent inflammatory response in their brain. The inflammatory processes include proliferation and activation of microglia and astrocytes, increased expression of cytokines/chemokines, and activation of the complement system. It has been demonstrated that reactive astrocytes surround both Aβ plaques and tau tangles. In this condition, glial cells lose some of their homeostatic functions and acquire a proinflammatory phenotype amplifying neuronal damage. Therefore, molecules that are able to restore their physiological functions and control the neuroinflammatory process offer new therapeutic opportunities for this devastating disease. Due to multifactorial etiology, the drug therapy of AD is very complex and poses a big challenge to the physicians. Currently used drugs alleviate the symptoms of AD but do not treat the underlying causes of dementia. Hence, a worldwide quest is under way to find new treatments to stop, slow, or even prevent AD. Besides the classic targets of the oldest therapies, represented by cholinergic and glutamatergic systems, new therapeutic approaches targeting β-amyloid (Aβ) plaques, tau tangles, and reactive gliosis (neuroinflammation) are emerging. These targets present multiple opportunities to create disease-modifying therapies for AD. Perhaps some modulators of the aforementioned targets have shown promising results in animal studies and are currently in clinical trials.
Human Neural Stem Cells as Model Systems to Understand Neurodegeneration
NeuroAIDS Laboratory, Molecular & Cellular Neuroscience, National Brain Research Centre, Manesar, Haryana, India
Address for correspondence: Prof. Pankaj Seth, NeuroAIDS Laboratory, Molecular & Cellular Neuroscience, National Brain Research Centre, Manesar − 122 051, Haryana, India.
The human central nervous system (CNS) is susceptible to bacterial and viral infections. Although rare, CNS infections have devastating consequences leading to high mortality and morbidity. Apart from several neuropathogens, human immunodeficiency virus (HIV-1) is known to traffic into the human brain and cause damage to the neural cells. The presence of HIV-1 in HIV/Acquired immune deficiency syndrome(AIDS) patients prompted basic and clinical neuroscientists to study the mechanisms as to how HIV enters the brain and the subsequent damage it may cause to the brain tissue. It has been reported that the virus traffics into the brain by Trojan horse mechanism via circulating monocytes, as they assist the virus in circumventing the protection at the blood–brain barrier level. Once in the brain, HIV-1 infects and resides in the glial cells, particularly the microglia and astrocytes. HIV-1 lodges itself in three major regions of the brain namely frontal cortex, hippocampus, and basal ganglia. Although infection of the neurons by HIV-1 is rare, HIV-1 and its proteins cause significant neuronal death, most of which is through the infection of neighboring glial cells. Post-mortem studies in pediatric samples have revealed that HIV-1 also exists in the human neural stem/precursor cells, which necessitated the investigations into cellular and molecular pathways involved in HIV-1-mediated effects on neural stem/precursor cells. HIV-1 and its proteins are linked to cause motor and cognitive deficits in HIV/Acquired immune deficiency syndrome(AIDS) patients, which are collectively termed as HIV-associated neurocognitive deficits (HAND). Up to 50% of HIV/Acquired immune deficiency syndrome(AIDS) patients experience mild cognitive motor disorders or HAND, which is primarily due to virus-induced neuronal damage. One of the major challenges of studies with neuroAIDS is the lack of animal models apart from scarcity of brain autopsy samples at various stages of HIV-1 neuropathogenesis. At National Brain Research Centre(NBRC), we have established an in-vitro model system of human fetal brain-derived neural stem/precursor cells that can investigate effects of HIV and its proteins on human neural stem cells, differentiating neural stem cells as well as primary cultures of astrocytes and neurons. Using this unique primary cell culture resource in the country, we have made several novel research findings. HIV-1 transactivator of transcription (Tat) protein perturbs the proliferative and differentiation ability of human neural stem cells by altering genes important for stemness and neurogenesis. More recently, we have made significant discoveries in glia-mediated neuronal damage and demonstrated the role of purinergic receptors in astrocytes-mediated neuronal damage. The role of stem cell fate determinant such as TRIM32 has also been demonstrated by HIV-1 Tat-mediated alterations of stemness of neural progenitor cells. Our observations have immense clinical importance for AIDS patients suffering HIV-1-associated neurocognitive disorders.
The research work has been supported by research grants to PS by the Department of Biotechnology, and core funds of National Brain Research Centre, Manesar, India.
Novel Strategies for Neuroprotection
R. V. Omkumar
Molecular Neurobiology Division, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India
Address for correspondence: Dr. R. V. Omkumar, Molecular Neurobiology Division, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India.
Neurons are terminally differentiated cells that cannot divide. Therefore, the loss of neurons in adulthood causes irreparable damage to the brain. One of the prominent biochemical mechanisms that cause neuronal death in response to various external stressors is excitotoxicity. Overload of Ca2+ inside the cell due to excessive activation of Ca2+ channels is the primary cause of excitotoxicity. An approach that has been tried toward protecting neurons from excitotoxicity is to inhibit the activity of Ca2+ channels using blockers so that Ca2+ influx into cytosol is reduced. The major Ca2+ channel responsible for excitotoxicity is the NMDA-type glutamate receptor (NMDAR). Although several blockers of NMDARs were developed, their success in bringing about neuroprotection at the clinical level has so far been limited. This calls for a review of the current strategy and development of alternative approaches.
NMDAR has several subtypes arising from different combinations of subunits. These subtypes differ among themselves in their pharmacological and electrophysiological properties and also in their spatiotemporal distribution. It is necessary that these subtypes be targeted selectively for effective drug therapy. Most of the currently used drugs lack subtype specificity. Greater emphasis on development of subtype-specific drugs is a potential new strategy for better success in neuroprotection by NMDAR antagonists.
The lack of sufficient number of drugs, particularly those targeting NMDAR subtypes, could have been a consequence of the difficulties faced by the drug discovery process. Screening for drugs critically depends on the assay used for NMDAR activity. Drug screening against NMDAR uses electrophysiology or calcium imaging as activity assays. These methods are real time in nature and, hence, are technically demanding as well as expensive. We have developed a novel endpoint assay for calcium channels that is simple to use and is less expensive with the potential to aid high throughput screening efforts. In a limited screening for NMDAR inhibitors using this assay, we have identified several small molecules with NMDAR inhibitory potency. We have also identified a plant extract that inhibits a subtype of NMDAR. The extract also showed neuroprotective activity against excitotoxicity in primary cortical neurons in culture and in vivo.
We have also analyzed biochemical changes in the brain during excitotoxicity toward identifying downstream steps that could be drug targets. Many of the biochemical changes induced by excitotoxicity were prevented upon neuroprotective treatment by the NMDAR inhibitory plant extract that we identified. The facilitation provided by the new calcium channel assay methodology, the realization of the importance of subtype targeting, and the identification of new downstream steps as druggable targets are new approaches toward developing strategies for neuroprotection.
Banking the Brain and Blood: Lifestyle Factors, Nutrigenomics, and Nutraceuticals Leading to Healthy Brain Aging
K. Ranil D. De Silva
Interdisciplinary Center for Innovation in Biotechnology & Neuroscience, Faculty of Medical Sciences, University of Sri Jayewardenepura (USJP), Sri Lanka
Address for correspondence: Prof. K. Ranil D. De Silva, Interdisciplinary Center for Innovation in Biotechnology & Neuroscience, Faculty of Medical Sciences, University of Sri Jayewardenepura (USJP), Sri Lanka.
Studying environmental, cultural, lifestyle, and genetic factors, such as gene-diet interaction (nutrigenomics) leading to healthy brain aging and longevity, is crucial for identifying differential responses in clinical settings, as well as neurobiologic biomarkers that may be associated with neurological diseases. The human brain bank and Deoxyribonucleic acid(DNA), repository established in Sri Lanka is one of the largest biobanks in the Indian subcontinent that could facilitate as a cornerstone in translational neuroscience.
Primarily, we examined the possible protective role of Sri Lankan diet on healthy brain aging, and it was studied utilizing the following: the established Human Brain Tissue (n = 76) and DNA/Gene Bank of patients and controls with stroke, as well as neurodegenerative and neuromuscular disease, from one of the largest biobanks in the South Asian region (over 2500). Anatomicopathological studies were performed in cerebral arteries of 447 adult and 34 fetal postmortem brains and gene expression studies in six cerebral arteries. Age-related cytoskeletal pathologies were studied in 76 aging and diseased human brains using histopathological/immunohistochemical techniques for tau and β-amyloid biomarkers, and vascular genetic variants such as apolipoprotein E, angiotensin-converting enzyme, methylene tetrahydrofolate reductase (MTHFR C677T), and factor V Leiden (FVL G1691A).
We performed the first-ever comparison between Sri Lanka (Colombo, n = 50) and India (Bangalore, n = 42) on age-related cytoskeletal pathologies in aging autopsy brains, thus indicating the true extent of dementia burden in this part of the world. Furthermore, an in-vitro hypoxic model using human brain epithelial cells was studied with treatment of Ceylon green tea extract before inducing hypoxia.
The author will discuss the prevention of cumulative risk and formulate interventions in preventative neuroprotective measures through natural products, nutrigenomics, and lifestyle factors for optimization of better brain health. Furthermore, ongoing research by the author based on natural products would lay a stepping-stone for developing neuroprotective nutraceuticals based on unique regional natural products.
Traffic Jams in Neurons
Department of Biological Sciences, Tata Institute of Fundamental Research (TIFR), Mumbai, Maharashtra, India
Address for correspondence: Dr. Sandhya Koushika, Department of Biological Sciences, Tata Institute of Fundamental Research (TIFR), Mumbai, Maharashtra, India.
Neurons communicate with each other at synapses through the process of synaptic transmission. The synapse can be up to a meter away from the cell body necessitating a robust transport process to bring all components required for synaptic transmission to the synapse. The axon that connects the cell body with synapses provides a highway for cargo movement, enabling neurons to both develop and maintain synaptic connections. Synaptic vesicles are a prominent and essential axonal cargo. We find that synaptic vesicle precursor transport is physically obstructed at actin-rich regions that contain other cargo. This obstruction affects local cargo flow and runs lengths of individual vesicles. Computational modeling shows that the ability to resolve or go past traffic jams is critical for cargo flow. Our results have implications for the progression of neurodegenerative diseases.
Genetics of Trinucleotide Repeat Disorders: Past to Present
Department of Medical Genetics, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, Uttar Pradesh, India
Address for correspondence: Prof. Sarita Aggarwal, Department of Medical Genetics, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, Uttar Pradesh, India.
A number of human-inherited neurological disorders are caused by the dynamic expansion of trinucleotide repeats in specific, functionally unrelated genes. Though in normal individuals the repeat size varies, it remains within a threshold limit. However, in triplet repeat expansion diseases (TREDs), the repeat size exceeds the threshold resulting in a pathogenic outcome. On the basis of the localization of repeats in transcripts, TREDs are classified into coding (Huntington’s disease and most spinocerebellar ataxia) and noncoding repeat expansion disorders (fragile X syndrome, myotonic dystrophy, spinocerebellar ataxias 8 and 12, and Friedreich’s ataxia). TNR disorders generally show genetic anticipation, and severity increases with each successive generation. These dynamic expansions result in variability in age of onset, degree of severity, and clinical presentation depending on repeat size. Individuals carrying alleles in the intermediate range, known as premutation alleles, are often asymptomatic, but can potentially transmit a further expanded allele to his/her offspring. An early diagnosis and symptoms management will greatly benefit affected patients. Molecular diagnosis of TREDs involves determination of the repeat size. Conventional Polymerase Chain Reaction(PCR) had been valuable in the past to assess the variability of expansion, but owing to its complexity, long stretch of trinucleotide repeat tract depicts refraction to amplification. In the past, these large alleles were measured by southern blot, which is technically demanding, labor intensive, and expensive technique requiring large quantities of Deoxyribonucleic acid (DNA) for analysis. Presently, advanced PCR-based methods have emerged, which are useful in establishing the diagnosis. Triplet Repeat Primed-Polymerase Chain Reaction(TP-PCR) is a robust and rapid method to accurately size normal and premutation alleles, but sizing of large expanded alleles becomes impossible as the larger alleles are less amplified. Fortunately, long-range Polymerase Chain Reaction(PCR) that involves special Taq polymerase with high fidelity and progressivity when coupled with long extension time with increment can amplify these expanded alleles. Mostly, the expanded allele gets methylated; such a methylated expanded allele can be identified with the help of methylation TP-PCR. Similarly, methylation-sensitive PCR can be used to discriminate between methylated and nonmethylated alleles; however, it cannot amplify full expansion mutations. Such advanced molecular diagnostics facilitate in correct diagnosis of all the TREDs, though having overlapping clinical features. Genetics testing can be used in different scenarios such as diagnostic testing, predictive testing, prenatal testing, carrier testing, and risk factor assessment.
Development of Repurposed Drugs for Neuroscience: An Example From Academia
Neuropharmacology Division, Department of Pharmacology University College, Oxford, London, United Kingdom
Address for correspondence: Prof. Travor Sharp, Neuropharmacology Division, Department of Pharmacology University College, Oxford, London, United Kingdom.
After its serendipitous discovery 60 years ago, lithium is currently the mainline treatment for bipolar depression and suicide prevention. However, the full therapeutic potential of lithium in these disorders and others linked to loss of impulse control is unmet due to poor tolerance and adverse effects such as renal damage, and a low therapeutic index requiring that patients taking lithium require regular blood monitoring. Although lithium’s mechanism of action is uncertain, a leading candidate is inhibition of inositol monophosphatase (IMPase) and reduced neurotransmitter signalling via Gq-coupled receptors and the phosphoinositide pathway. So far, attempts by the pharmaceutical industry to develop small molecule inhibitors of IMPase have been hampered by limited bioavailability of the drug hits.
Recently, we screened a library of compounds found to be safe in humans and identified ebselen as a potent, brain penetrant inhibitor of IMPase. Ebselen has been used in clinical trials for stroke but not marketed. Our experiments show that ebselen has lithium-like effects in a range of pre-clinical models including reduced function of a specific Gq-coupled 5-HT receptor (5-HT2A) in molecular and behavioural assays. The latter observation is of interest because the 5-HT2A receptor is linked to impulsivity control. Indeed, our experiments show that ebselen decreases impulsivity in different behavioural models, likely through a 5-HT2A receptor mechanism. These findings have provided a rationale for the repurposing of ebselen for disorders such as bipolar depression, which feature high impulsivity, and its rapid progression to proof-of-concept studies in healthy volunteers, which are ongoing.
Career in Medical Communications: Is it Right for You?
Global Medical Affairs (Respiratory), Cipla Ltd., Mumbai, Maharashtra, India
Address for correspondence: Dr. Vaibhav Gaur, Global Medical Affairs (Respiratory), Cipla Ltd., Mumbai, Maharashtra, India.
Be it academics or industry, no one can deny the importance and significance of communicating the data or the information that is generated. Especially, from a pharmaceutical company standpoint, development of a drug takes years before it reaches the hands of a patient. It goes through different phases from molecule synthesis, preclinical phases, to clinical phases, which generate huge amount of information about the product. Furthermore, even after the approval, companies would keep on generating more data in the form of postmarketing studies, surveys, and studies for other indications. Medical Communications (med comms) has emerged as a very important department in the pharmaceutical industry to generate written, audiovisual, oral, or online materials dealing with medicine and healthcare. Although the conduct of pharmaceutical development has always been heavily regulated, regulations on the communications have also started evolving since the last decade. The session will provide an overview of medical writing and where it fits in the spectrum of a pharmaceutical company, guidelines for publications, good publication practices, and career possibilities for the researchers and students in med comms.
In Vitro Determination of Carbonic Anhydrase Inhibition of the Flowers of Vanda Orchid, Vanda tessellata Roxb. (1795) by Modified Colorimetric Maren T.H. (1960) Method
John Carlo Combista, Dorothy Mae Perez, Jimbert A. Tan
Department of Pharmacy, University of San Carlos and School of Healthcare Professions, Philippines
Address for correspondence: John Carlo Combista, Department of Pharmacy, University of San Carlos and School of Healthcare Professions, 6000, Philippines.
The orchid, Vanda tessellata was chosen by the researchers because of the presence of the constituents such as alkaloids, flavanoids, and glycosides in the family Orchidaceae that might give an inhibition activity of the carbonic anhydrase enzyme. This study aimed to determine the in vitro inhibition of carbonic anhydrase of V. tessellata flower extract. With the use of modified colorimetric Maren T.H. (1960) method, the time in seconds for each test solution to change its color after the rate of CO2 hydration was recorded. Two solvents were used for the extraction: the semipolar, 95% ethanol and the nonpolar, dichloromethane solvents. The percent inhibition activity of carbonic anhydrase of the different concentrations of ethanol-based extract (1, 25, and 50%) and dichloromethane-based extract (1 and 10%) test solutions were determined. Results showed that the ethanol-based extracts of V. tessellata in different concentrations have an inhibitory effect, whereas the dichloromethane-based extracts of V. tessellata showed noinhibitory effect in all. For ethanol-based extracts, the concentration with the highest activity was 50% followed by 25%, which changed its color from red to yellow with an average time of 13.11 and 11.57 s, respectively. However, 1% concentration with an average time of 7.56 s did not exhibit an effect. The researchers recommend utilizing different blood types to observe different reactions to the inhibition of carbonic anhydrase. The enzymes to be added to the test solutions must be quantified. The positive control, freshly prepared, should not be limited to only one concentration, and the test solutions should have concentrations greater than 50%. Phenol red indicator and pH of the buffer must be checked and monitored from time to time to ensure their sensitivities. Other indicators were used especially when working with colored extracts or test solutions. Finally, the specific active constituent of V. tessellata that is responsible for the inhibitory effect of carbonic anhydrase enzyme is isolated.
Genotype–Phenotype Characterization of Spinocerebellar Ataxias (SCAs) in Sri Lanka
Lakmal Gonawala, Nalaka Wijekoon, Vindika Suriyakumara, Darshna Sirisena1, Ranjani Gamage2, Harsha Gunasekara3, Sunethra Senanayake2, Mohammed Faruq4, Ashwin Dalal5, Harry W. M. Steinbusch6, Ranil De Silva
Interdisciplinary Center for Innovation in Biotechnology & Neuroscience, University of Sri Jayewardenepura, 1Teaching Hospital, Kurunegala, 2National Hospital of Sri Lanka, Colombo, 3Sri Jayewardenepura General Hospital, Colombo, Sri Lanka, 4Institute of Genomics and Integrative Biology, New Delhi, Delhi, 5Centre for DNA Fingerprinting & Diagnostics, Hyderabad, Telangana, India, 6European Graduate School of Neuroscience, Department of Translational Neuroscience, The Netherlands
Address for correspondence: Lakmal Gonawala, Interdisciplinary Center for Innovation in Biotechnology & Neuroscience, University of Sri Jayewardenepura, Sri Lanka.
Personalized therapies for spinocerebellar ataxias (SCAs) is challenging given the diverse genetic causes of SCA and variability in clinical features, even in a defined genetic cause, which can vary among ethnic populations. To perform genetic analysis of Sri Lankan clinically diagnosed SCA patients and to evaluate genotype–phenotype correlation, SCA patients (n = 68) aged 18–73 years [male − 34 (50%) and female − 34 (50%)] [familial inheritance n = 38 (56%); paternal − 22 and maternal − 16] were studied. Sociodemographic factors, clinical data (scale for the assessment and rating of ataxia (SARA), unified Huntington disease rating scale − Unified Huntington Disease Rating Scale (UHDRS) functional scale, extrapyramidal symptoms (EPS), ophthalmological signs, oculomotor deficits, etc.), and family history were recorded. Connected Acyclic Graph (CAG) repeat analysis was performed for SCA1, SCA2, SCA3, and SCA12. SCA subtypes were SCA1 (n = 29, mean AO = 35.8 ± 10 years), SCA2 (n = 10, mean AO = 33.8 ± 13 years), and SCA3 (n = 11, mean AO = 39 ± 9 years). Genetic etiologies of n = 20 were to be elucidated for other subtypes with clinical heterogeneity. Mean CAG repeat length of normal/abnormal alleles of SCA1 was 28.3 ± 2/54.6 ± 6, for SCA2 was 22 ± 1/42.3 ± 5, and for SCA3 was 26 ± 2/58.6 ± 10. UHDRS functional scale mean score was as SCA3 > SCA2 > SCA1; SCA1 versus SCA2–P > 0.03 and SCA1 versus SCA3–P > 0.009; SARA mean score was as SCA1 > SCA2 > SCA3; SCA1 versus SCA3–P > 0.003 and SCA2 versus SCA3–P > 0.03. Oculomotor, nystagmus (P > 0.04), slow saccades (P > 0.01), and dysphagia (P > 0.03) were significant in SCA1; SCA1 functional ability correlates with EPS − myoclonus P > 0.007 and rigidity P > 0.03. Resultant interpatient variability in genotypes to clinical phenotypes from a genetically admixture population of South Asian origin warrants similar studies with a large sample size that would be a unique resource toward future personalized medicine.
Comparative Study of Simple Visual and Auditory Reaction Time in Healthy Participants
M. Bade, N. Banjara
Department of Physiology, Kathmandu University School of Medical Sciences, Dhulikhel, Nepal
Address for correspondence: M. Bade, Department of Physiology, Kathmandu University School of Medical Sciences, Dhulikhel, Nepal.
Reaction time is the minimum time needed to respond to a stimulus. It is a non-invasive procedure for determining sensorimotor coordination. The objective of the study was to find out whether the reaction time was faster for auditory or visual stimuli in males and females. The study was conducted on 120 young right-handed healthy participants (60 males and 60 females) of age 10–14 years with normal hearing and sighted vision after obtaining approval from the Ethical and Institutional Review Committee. Auditory and Visual reaction time was recorded using DirectRT software program. Participants performed both visual and auditory reaction tests. The mean auditory and visual reaction time was calculated by excluding the first and last values after the data was obtained. There was a significant variation of auditory and visual reaction time in both males and females. Auditory reaction time was faster than visual reaction time in both males and females. Visual and auditory reaction time was shorter in males compared to females.
Synaptic Plasticity and Memory Deficits in Rat Model of Acute Kidney Injury
Maryam Arab Firouzjaei, Mostafashid Moosavi
Zanjan University of Medical Science, Iran
Address for correspondence: Maryam Arab Firouzjaei, Zanjan University of Medical Science, Iran.
Recent evidence suggests that renal ischemia/reperfusion may have impairment effects on brain function. Therefore, this study aims to investigate the effects of bilateral or unilateral renal ischemia reperfusion on learning memory and hippocampal synaptic plasticity. The model groups were established by bilateral or unilateral renal ischemia for 60 and 120 min, respectively and 24 h of reperfusion. A shuttle box apparatus was used for passive avoidance learning and memory assessment. Moreover, the animals were evaluated for synaptic plasticity by field potential recording. The results of this study demonstrated that the 60 min bilateral or 120 min unilateral renal ischemia along with 24 h of reperfusion resulted in impaired long-term potentiation and memory performance. Particularly, the field potential recording demonstrated that bilateral and unilateral renal ischemia led to extreme inhibition in long-term potentiation compared to the control and sham groups; this inhibition was accompanied by a significant increase of the normalized Polypropylene random copolymer (PPR) (PPR after HFS/PPR and before Hardware functionality scan (HFS)) as an index for release probability. The behavioral results verified the electrophysiological assessment data, in which the renal ischemia groups showed significant increase in step-through latency during passive avoidance task in comparison with the sham and control groups. Our data suggest that renal ischemia/reperfusion induces injurious distant effects on the hippocampus associated with synaptic plasticity and memory deficits. Studies on other techniques are ongoing, such as western blotting for evaluating the expression of caspase 3 and a stereologic study for the assessment of the hippocampus structure.
FTY720 Ameliorates Memory Performance and Synaptic Plasticity Deficits in a Rat Model of Brain Ischemia
M. Nazari, S. Keshavarz, A. Rafati, M. R. Namavar, M. Haghani
School of Advanced Medical Sciences and Technologies, Iran
Address for correspondence: M. Nazari, School of Advanced Medical Sciences and Technologies, 7197673567, Iran.
Ischemic stroke occurs when an artery in the brain is blocked. The middle cerebral artery is most often occluded by atherosclerotic or thrombotic processes. The brain ischemia elicits numerous pathogenic cascades that develop over time and space, causing injury to the neurons. In the hippocampal CA1 pyramidal cells, hypoxia induces major change in the electrophysiological responses. It has been suggested that middle cerebral artery occlusion (MCAO) impairs the long-term potentiation (LTP) induction in Schaffer collateral-CA1 synapses. Fingolimod (FTY720) is a known sphingosine-1-phosphate receptor agonist. Several studies have shown the therapeutic efficacy of FTY720 in neurodegenerative disorders. However, the neuroprotective mechanisms in brain ischemia have not been adequately studied. Therefore, this study aimed to investigate the effects of FTY720 on the impairment of learning and memory and hippocampal synaptic plasticity induced by MCAO in ischemic brain injury. Twenty-eight male rats were randomly divided into four groups of control (n = 7), sham (n = 8), ischemic-reperfusion + vehicle (I/R + V; n = 7), and I/R + FTY720 (n = 6). After 1 h of the occlusion of artery, the filament was gently withdrawn to allow reperfusion for the next 7 days. The animals first received a dose of FTY720 (0.5 mg/kg) or its vehicle (intra-peritoneal) 24 h before surgery in I/R + FTY720 and I/R + V groups, respectively. The administration of FTY720 or its vehicle continued every other day. Neurologic assessment was performed 24 h after the surgery. The passive avoidance test and field potential recording were used for evaluation of learning, memory, and synaptic plasticity. The field potential recording was performed 7 days (reperfusion period) after the initial procedure. The brain infarct volume was measured by triphenyltetrazolium hydrochloride staining. The neurologic deficit was scored at 24 h after the MCAO, and the results did not show a significant difference between MCAO + V and MCAO + FTY720 groups. However, the neurological deficit scores of both ischemic groups were statistically higher than the control and sham groups. MCAO caused infarct damage in the rat’s brain tissue. The administration of FTY720 significantly reduced the size of the lesion, improved the memory impairment of MCAO rats, and increased the STL time. In addition, the field potential recording demonstrated a marked reduction in induction of long-term potentiation of MCAO animals. However, administration of FTY720 recovers the magnitude of the LTP without any effects on presynaptic plasticity and neurotransmitter release probability. The results of this study demonstrated that MCAO in rats impairs the retention of passive avoidance tasks, and multiple injection of FTY720 improved the memory performance after MCAO by LTP induction via postsynaptic mechanisms. In addition, a single injection was not sufficient to rescue at least the neurological score 24 h after ischemia. Thus, administration of FTY720 may be a promising therapy for recovery of memory and synaptic plasticity impairment after MCAO.
Investigating the Locus Coeruleus Neuropathic Pain-Induced Synaptic Plasticity and the Role of This Nucleus in Attention Deficit Disorder
Parisa Moazen, Saeed Semnanian
Shiraz University, Iran
Address for correspondence: Parisa Moazen, Shiraz University, Iran.
Pain is a multidimensional experience with sensitive − discriminative and motivational − affective dimensions. Persistent pain, including chronic pain syndromes, is a common condition associated with a wide spectrum of disorders including cancer, inflammation, and neuropathic pain. Neuropathic pain (NP) is caused by a primary lesion or dysfunction of the nervous tissue and results in prolonged hyperalgesia, allodynia, and spontaneous pain. NP results from a process of peripheral and central sensitization that generates an enhanced transmission of nociceptive input to the brain, which may impair the endogenous supra-spinal pain control system. On the other hand, chronic pain induces cognitive disorder, including attention deficit disorder (ADD). In chronic pain, action potentials fire at a higher rate in nociceptors, which carry pain information to several brain areas that are common between pain and cognition. Cognitive and behavioral disorders might be the result of functional impairment of neural substrates that affect pain, emotion, reward, motivation, and cognitive processing. One of the most important substrates that might impinge on these different circuits is noradrenergic nucleus locus coeruleus (LC). LC provides the bulk of norepinephrine found in the Central nervous system(CNS). ADD could be the result of a functional impairment in noradrenergic circuits associated with LC and prefrontal cortex, where cognitive and sensorial pain processes overlap. The LC is a central component of the descending inhibitory system and plays a crucial role in cognitive processes such as attention. Moreover, the LC may be involved in cognitive disorders caused by pain. On the other hand, it is possible that neuroplasticity in LC that is caused by persistent pain may contribute to create or develop these disorders. In addition, electrophysiological studies indicate that changes in the LC activity can be caused by chronic pain situations, such as neuropathic pain. The onset of behavioral changes caused by neuropathic pain coincided with irruption of noradrenergic dysfunction, evident as an increase in LC bursting activity, tyrosine hydroxylase expression, noradrenaline transporter amount, and sensitivity of α2-adrenoceptors in the LC. Therefore, we hypothesized that chronic pain induces ADD that is associated with neuroplasticity of the LC. To assess this hypothesis, we will perform an attention behavioral test for comparing attention between neuropathic rats and the same rats in which their LC is pharmacologically lesioned. In addition, electrophysiological studies shall be performed for evaluating synaptic plasticity in the LC after the induction of neuropathy.
Neurocysticercosis: Clinico-Radiological Profile and Outcome at BPKM Cancer Hospital
Quamrul Haque Ansari, Laxmi Narayan Singh
B.P. Koirala Memorial Cancer Hospital, Bharatpur, Chitwan, Nepal
Address for correspondence: Dr. Quamrul Haque Ansari, B.P. Koirala Memorial Cancer Hospital, Bharatpur, Chitwan 44200, Nepal.
Introduction Neurocysticercosis (NCC) is one of the most common causes of seizures and epilepsy in the developing world. There is insufficient information about NCC in Nepal. This study was, therefore, conducted to evaluate the clinical, neuro-radiographic and therapeutic aspects of NCC at B.P. Koirala Memorial (BPKM) Cancer Hospital.
Materials and Methods One hundred patients with neurocysticercosis were studied prospectively for 12 months in the BPKM Cancer Hospital, a secondary-level referral hospital in central Nepal. The diagnosis of NCC was based primarily on the neuro-imaging (CT scan) findings.
Results The patients were predominantly females (nearly 60%) with age ranging from 5 to 70 years. School-aged children constituted 35% of the patients. The three common manifestations were seizures (95%), headache and/or vomiting (40%). Computed Tomography(CT) scan demonstrated a single parenchymal ring or nodular enhancing lesion in 84% of the cases with perilesional oedema in nearly 85% of the cases. A large majority of the patients were treated only with the anti-convulsant drugs for 9 months. Follow-up with repeat CT after 9 months showed a complete resolution of NCC in most of the cases without the need for cysticidal treatment.
Conclusion NCC should be considered first in the differential diagnosis of new-onset seizure among the patients of developing countries, where taeniasis is endemic. Most of the patients with neurocysticercosis do not need anti-cysticercal therapy.
The Effect of Acute Exercise on Working Memory Performance
S. K. Deo, P. Bhattrai, K. Agrawal
Department of Physiology, Birat Medical College, Morang, Nepal
Address for correspondence: Dr. P. Bhattrai, Department of Physiology, Birat Medical College, Morang, Nepal.
The purpose of this study was to compare the influence of acute, moderate-intensity aerobic exercise on the speed and accuracy of working memory tasks. Participants (N = 30; 20 males and 10 females; age: M = 22.3; range = 21–28 years) completed a dual n-back working memory task before the start, immediately after and 5 min after an intervention of exercise. Findings revealed a significant beneficial influence (t = 2.55, P ≤ 0.05) of moderate exercise on the accuracy of working memory after a rest of 5 min after exercise. In contrary, no significant relation between the speed of working memory performance and exercise was found. This work indicates that acute aerobic exercise is effective in improving working memory function and may be beneficial for healthy adults whose cognitive performance is relatively low.
Activation of the Complement Cascade and the NLRP3 Inflammasome by HSOD1G93A Protein
Vandana Deora, Luke McAlary1,2, Justin Yerbury1,2, Richard Gordon, Trent M. Woodruff
School of Biomedical Sciences, University of Queensland, Brisbane, 1School of Biological Sciences, Faculty of Science, University of Wollongong, Wollongong, New South Wales, 2Illawarra Health and Medical Institute, University of Wollongong, Wollongong, New South Wales, Australia
Address for correspondence: Vandana Deora, School of Biomedical Sciences, University of Queensland, Brisbane, Australia.
Motor neuron disease (MND) is an incurable neurodegenerative disorder characterized by a progressive loss of motor neurons in the motor cortex, brain stem, and spinal cord. It leads to atrophy and weakness of bulbar, limb, and respiratory muscles. There is increasing evidence that activation of the innate immune system leading to chronic neuroinflammation can drive the progression of MND. Two key components of the innate immune system that have recently been proposed to play an important role in MND pathology and progression are the NLRP3 inflammasome and the complement system. The NLRP3 inflammasome is an intracellular protein complex that mediates the generation of mature IL-1β via caspase-1 activation and has been recently implicated in Alzheimer’s disease pathology by responding to beta-amyloid fibrils. The complement system is a cascade of secreted molecules that react to pathogens and protein aggregates, which also has documented roles in MND. The current study aimed to determine if the NLRP3 inflammasome and the complement system are activated in response to a MND-relevant protein, SOD1G93A. Microglial cultures were treated with mutant SOD1G93A protein, and inflammasome activation determined by western blotting and ELISA. We found that soluble and aggregated mutant SOD1 protein triggers IL-1β secretion from LPS-primed microglia, as well as generating the cleaved form of caspase-1. These results indicate that activation of the inflammasome pathway, leading to increased expression of caspase-1, IL-1β, and NLRP3 can occur in response to a MND mutant protein. In addition, we found that SOD1G93A protein aggregates also activated the complement cascade, generating the terminal complement component C5a from lepirudin plasma. Taken together, these findings suggest that NLRP3 inflammasome activation and C5a signaling could be potential downstream pathological mechanisms triggered by neurotoxic proteins seen in MND. Inhibiting these innate immune pathways may thus be a means to slow propagative neuroinflammatory cell death in MND and ameliorate disease progression.
Abstracts of National Participants
QSAR Analysis of Isatin (Indole-2,3-Dione) as Selective Inhibitor of Carboxylesterases
Achal Mishra, Sarvesh Paliwal
Faculty of Pharmaceutical Sciences, Shri Shankaracharya Technical Campus, Durg, Bhilai, Chhattisgarh, India
Address for correspondence: Achal Mishra, Faculty of Pharmaceutical Sciences, Shri Shankaracharya Technical Campus, Durg, Bhilai, Chhattisgarh, India.
A two- and three-dimensional quantitative structure-activity relationship (QSAR) using Medical Loss Ratio(MLR), Polymerase Chain Reaction(PCR), Partial least Square(PLS) and k-nearest neighbor molecular field analysis methods was performed on a series of isatin derivatives as carboxylesterase (CE) inhibitors. This study was performed with 49 compounds (data set) using sphere exclusion (SE) algorithm for the division of the data set into training and test set. SE algorithm allows constructing training sets covering all descriptor space areas occupied by representative points, between 3.0 and 5.5 dissimilarity levels, which comprise test set size 4–10. Medical Loss Ratio(MLR), Partial least Square(PLS), Polymerase Chain Reaction(PCR) and k-nearest neighbor method(kNN-MFA) methodologies with stepwise (SW), simulated annealing (SA) and genetic algorithm (GA) were used for building the QSAR models. Four predictive models were generated with SW-kNN MFA (pred_r2 = 0.7552–0.9376), three predictive models were generated with SA-kNN MFA (pred_r2 = 0.7019–0.9367) and two predictive models were generated with GA-kNN MFA (pred_r2 = 0.8226–0.8497). Most significant model generated by stepwise k-nearest neighbor method(kNN-MFA) showed internal predictivity as 82.11% (q2 = 0.8211) and external predictivity as 93.76% (q2 = 0.9376). In this model, hydrophobic and steric interactions dominate the CE inhibitory activity. Hydrophobic field descriptor (H_977) with positive range indicates that positive hydrophobic potential is favourable for increase in activity and, hence, more hydrophobic substituent group is preferred in that region. Steric field descriptor (S_619) with negative range indicates that negative steric potential is favourable for increase in activity and, hence, less bulky substituent group is preferred in that region. The k-nearest neighbor method(kNN-MFA) contour plots provided further understanding of the relationship between structural features of substituted isatin derivatives and their activities, which should be applicable to design newer potential CE inhibitors.
Formulation Development and Evaluation of Gastroretentive Mucoadhesive Microspheres of Metformin Hydrochloride
Alka Lohani, Anurag Verma
School of Pharmaceutical Science, IFTM University, Moradabad, Uttar Pradesh, India
Address for correspondence: Dr. Alka Lohani, School of Pharmaceutical Science, IFTM University, Moradabad, Uttar Pradesh, India.
The aim of this work is to formulate the mucoadhesive microparticulate system for oral delivery of metformin hydrochloride by using different mucoadhesive polymers [carbopol 934P, hydroxyl propyl methyl cellulose (HPMC) E15 and HPMC E60] alone or in combination. Microspheres were prepared by emulsification solvent evaporation method using span-80 as an emulsifying agent. Prepared microspheres were evaluated for shape, size, percentage yield, entrapment efficiency, in-vitro mucoadhesion, in-vitro drug release and stability. The microspheres obtained were spherical and free flowing. Percentage drug entrapment efficiency of microspheres was in the range of 68.2 ± 1.28 to 85.8 ± 2.22%. The result of the mucoadhesion study shows that all the formulations exhibit good mucoadhesion for more than 10 h. The drug release study shows that microspheres containing polymers in combination show sustained release for more than 12 h. By fitting the data into various kinetic models, it was calculated that the drug release followed zero-order release, as the correlation coefficient (r2) value was high for zero order and the value of release exponent (n) >1 indicated super case-II transport. On the basis of the results of evaluation tests, microspheres containing combination of carbopol 934P and HPMC E60 in the ratio of 1:1 and 6:4 (F10, F11), respectively were concluded to be the best formulations. The stability data of optimized formulation indicated no significant difference in percent entrapment efficiency, mucoadhesion and in-vitro drug release from the optimized formulations before and after storage. The results of this study showed that mucoadhesive microspheres could be a viable approach to improve the bioavailability of metformin hydrochloride.
Combined Potential of Calcineurin Inhibitor and PKA Activator in the Improvement of Memory Loss and Neuropathological Changes in Mouse Model of Dementia
Amit Kumar, Nirmal Singh
Department of Pharmaceutical Sciences and Drug Research, Punjabi University Patiala, Punjab, India
Address for correspondence: Dr. Amit Kumar, Department of Pharmaceutical Sciences and Drug Research, Punjabi University Patiala, Punjab - 147 002, India.
The study was designed to investigate the outcome of the combination of calcineurin (CaN) inhibitor (tacrolimus) and protein kinase A (PKA) activator (Forskolin) in mouse models of experimental dementia. Streptozotocin [STZ, 3 mg/kg, injected intracerebroventricularly (i.c.v.)] was used to induce memory deficits in NIH mice, and aged mice separately taken served as a natural model of dementia. Morris water maze (MWM) test was employed to evaluate learning and memory of the animals. A battery of biochemical and histopathological studies was also performed. The extent of oxidative stress was measured by estimating the levels of brain glutathione (GSH) and thiobarbituric acid reactive species (TBARS). Brain acetylcholinesterase (AChE) activity was estimated to assess cholinergic activity. The brain level of myeloperoxidase (MPO) was measured as a marker of inflammation. STZ (i.c.v.) and aging result in marked decline in MWM performance of the animals, reflecting impairment of learning and memory. STZ-treated mice and aged mice exhibited a marked enhancement of AChE activity, as well as TBARS and MPO levels, along with a fall in GSH level. Furthermore, the stained micrographs of STZ-treated mice and aged mice indicate pathological changes, severe neutrophilic infiltration and amyloid deposition. A combination of tacrolimus and forskolin significantly attenuated STZ-induced and age-related memory deficits, as well as biochemical and histopathological alterations. The findings demonstrate that the combination of CaN inhibitor and PKA activator has significantly alleviated memory dysfunction, biochemical alteration, and histopathological changes. It is concluded that the combination of CaN and PKA can be explored as a potential therapeutic target for dementia.
To Discover Novel and Selective JNK3 Inhibitors as Anti-Alzheimer’s Agents
Ashima Nagpal, Sarvesh Paliwal
Banasthali University, Banasthali, Rajasthan, India
Address for correspondence: Ashima Nagpal, Banasthali University, Banasthali − 304 022, Rajasthan, India.
C-Jun-N-terminal kinase inhibitors that have been developed and brought under clinical trials so far were more or less found to be inefficient or unsafe due to a number of reasons. The major and the most common problem encountered with C-Jun-N-terminal kinase inhibitors is the lack of specificity and selectivity, which is required for their therapeutic use against a single target. Due to poor selectivity or specificity or both, C-Jun-N-terminal kinase inhibitors inhibit the complete C-Jun-N-terminal kinase activity instead of any single activity. As JNKs regulate a number of cellular functions, inhibiting complete C-Jun-N-terminal kinase activity will certainly affect multiple processes, some of which are not linked to patho-physiology of disease. This could probably generate undesired side effects, which indeed will be more pronounced in case of chronic conditions. This is the reason why no C-Jun-N-terminal kinase inhibitor developed so far has been used against a particular disease or condition. With an aim to overcome the aforementioned drawbacks of the previously developed C-Jun-N-terminal kinase inhibitors, an attempt will be made to design novel JNK3 inhibitors with better specificity, selectivity as well as efficacy through the application of a battery of in-silico and in-vitro tools.
Effect of Camelia Sinensis (Green Tea) on Spatial Learning and Memory in REM Sleep-Deprived Albino Wistar Rats
Poojar Basavaraj, Bairy K. Laxminarayana
Department of Pharmacology, Kasturba Medical College, Manipal, Karnataka, India
Address for correspondence: Poojar Basavaraj, Department of Pharmacology, Kasturba Medical College, Manipal − 576 104, Karnataka, India.
Rapid eye movement (REM) sleep control animals were evaluated using the inverted flower pot method. The study animal was placed on a platform of diameter 15 cm, which was big enough with reference to the body size of the animal and allowed the relaxed position of Rapid eye movement (REM) sleep. This was done to rule out the possibilities of non-specific effects such as isolation. Rapid eye movement (REM) sleep deprivation: Inverted flower pot method was used for Rapid eye movement (REM) sleep deprivation. Herein, the animals were placed on a small platform of diameter 6.5 cm surrounded by a pool of water, in which the platform was small enough with reference to the body size of the animal. This technique is based on the loss of skeletal muscle tone typical of Rapid eye movement (REM) sleep, which is followed by the animal falling into water. Morris water maze was employed to evaluate learning and memory. Acquisition trials: Each animal was subjected to four consecutive trials with an interval of 5 min, during which the study animal was allowed to escape on the hidden platform and was allowed to remain there for 20 s for consecutive 3 days at (a) 24th h, (b) 48th h and (c) 72nd h. Retrieval trial: On the next day, that is, on the 96th h, the platform was removed and each study animal was allowed to explore the pool for 60 s.
Neuroprotective Effect of Dehydroepiandrosterone on the Rat Model of Post-Traumatic Epilepsy
Chandra Prakash, Deepak Sharma
Neurobiology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, Delhi, India
Address for correspondence: Dr. Chandra Prakash, Neurobiology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, Delhi, India.
Traumatic epilepsy is characterized by the occurrence of recurring seizures after severe brain injury. Epileptic seizures are implicated with oxidative stress, which triggers neuronal damage. This study investigated the effects of dehydroepiandrosterone (DHEA) in FeCl3-induced epilepsy in rats. DHEA, a neuroactive corticosteroid, was evaluated for its ameliorative effect against the FeCl3-induced seizures, oxidative stress, and antioxidant defense. Epilepsy was induced by injecting FeCl3 into the cerebral cortex of rats. DHEA was administered intraperitoneally to the FeCl3-induced epileptic rats for 7, 14, and 21 days. Epileptic rats showed increased seizures along with reduced acetylcholinesterase activity, enhanced lipid peroxidation and protein carbonylation, and reduction in the activities of antioxidant enzymes (catalase, superoxide dismutase, glutathione-s-transferase, glutathione peroxidase, and glutathione reductase) in the tissue homogenate of cortex and hippocampus. Treatment of rats with DHEA significantly reduced seizures and increased acetylcholinesterase activity. Moreover, results showed significant reduction of lipid peroxidation and protein carbonylation in the cortex and hippocampus of rats. There was significant restoration in the activities of all the antioxidant enzymes studied. In conclusion, these results demonstrate that suppression of FeCl3-induced seizure activity by DHEA against oxidative stress is balanced by the recovery of antioxidant enzymes.
Nanostructured Carriers Mediated Combination Therapy for Efficient Treatment of HIV-Associated Neurocognitive Disorders
Charan Singh, Bhupinder Singh Bhoop
National Institute of Pharmaceutical Education and Research, Mohali, Punjab, India
Address for correspondence: Dr. Charan Singh, National Institute of Pharmaceutical Education and Research, Mohali − 160 014, Punjab, India.
Intranasal drug delivery is a promising alternative for administration of drugs in systemic circulation, especially those that are ineffective orally and must be administered parenterally. Moreover, it will be advantageous for CNS targeting through nasal route using various formulation approaches. Lopinavir is potent, one of the frequently administered HIV protease inhibitors, and is greatly attenuated by a high first-pass hepatic metabolism. Quercetin (3,3,4,5,7-pentahydroxyflavone) is a dietary flavonoid present in vegetables, fruits, seeds, nuts, tea, and red wine. It exerts antioxidant activity by upregulating endogenous free radical defenses.
Betanin Attenuates Paraquat-Induced Oxidative Stress and Neurotoxicity in Drosophila Melanogaster
Department of Pharmacology, Bombay College of Pharmacy, Kalina, Mumbai, Maharashtra, India
Address for correspondence: Dimple Jhonsa, Department of Pharmacology, Bombay College of Pharmacy, Kalina, Mumbai − 400 098, Maharashtra, India.
Parkinson’s disease is a chronic, progressive neurodegenerative disorder, whose exact cause as well as its cure is unknown. Exposure to paraquat is employed to induce oxidative stress neurotoxicity and sporadic Parkinson’s disease. In this study, the therapeutic antioxidant properties of betanin against paraquat-induced oxidative damage and neurotoxicity in Drosophila melanogaster were examined. Adult flies were exposed to paraquat for 12 h and then treated with betanin. Mortality, locomotor behavior by negative geotaxis assay, and oxidative stress by determining total Reactive Oxygen Species(ROS), glutathione, and activities of superoxide dismutase and catalase were evaluated. Significant locomotor disability was observed among adult flies on exposure to paraquat solution for 12 h. More than 45% of flies fed on betanin survived as compared to 100% mortality observed in paraquat-treated flies at 24 h. In addition, the locomotor activity of paraquat-exposed flies was enhanced by 80–85% when treated with betanin for 24 h. Betanin ameliorated intracellular Reactive Oxygen Species(ROS) levels, superoxide dismutase, and catalase as compared to the levels increased by paraquat. They also reduced acetylcholinesterase activity, which was increased by paraquat. The levels of reduced glutathione, which were diminished by paraquat, were also enhanced by betanin. This study demonstrated that feeding flies with betanin after exposure to paraquat showed antioxidant and neural protective effects leading to the recovery of locomotor behavior and extension of life span. The project confirmed the utility of Drosophila melanogaster as a model in screening putative therapeutic molecules prior to their use in mammalian models.
Virtual Screening of Withania Somnifera to Search a Potent Neuroprotectant by Inhibiting GluN2B-Containing NMDA Receptors
Gaurav Kumar, Ranjana Patnaik
School of Biomedical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi, Uttar Pradesh, India
Address for correspondence: Gaurav Kumar, School of Biomedical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi − 221 005, Uttar Pradesh, India.
N-methyl-d-aspartate receptors (NMDARs) mediated excitotoxicity has been implicated in multi-neurodegenerative diseases. Due to lack of efficacy and adverse effects of NMDAR antagonists, search for herbal remedies that may act as therapeutic agents is an active area of research to combat these diseases. Withania somnifera (WS) is being used for centuries as a nerve tonic and nootropic agent. This in-silico study was designed to evaluate the neuroprotective efficacy of W. somnifera phytochemicals by allosteric inhibition of the GluN2B-containing NMDARs. We predict blood–brain barrier penetration, mutagenicity, drug-likeness and human intestinal absorption properties of 40 WS phytochemicals. Furthermore, molecular docking was performed to know whether these phytochemicals inhibit the GluN2B-containing NMDARs or not. The results suggest that withanolide A − a phytosteroid − can inhibit GluN2B-containing NMDARs through allosteric mode similar to the well-known selective antagonist ifenprodil. Therefore, withanolide-A could be developed as a potent neurotherapeutic drug to counter NMDARs mediated excitotoxicity and to treat multi-neurodegenerative diseases.
Modulation of Cyclooxygenase, Nitric Oxide and VGSC Contributes to the Analgesic Effect of Bergapten
Gurjit Singh, Anudeep Kaur, Palwinder Singh1, Rajbir Bhatti
Departments of Pharmaceutical Sciences and 1Chemistry, Guru Nanak Dev University, Amritsar, Punjab, India
Address for correspondence: Dr. Rajbir Bhatti, Department of Pharmaceutical Sciences, Guru Nanak Dev University, Amritsar, Punjab, India.
Bergapten (5-methoxypsoralen), a naturally occurring furanocoumarin, has been documented to have an interesting biological profile in several preliminary studies. The current investigation is aimed at exploring the analgesic and anti-inflammatory activities of bergapten. Swiss albino mice were used. Analgesic and anti-inflammatory activities of bergapten (10 mg/kg) were determined in formalin, and acetic acid induced hyperalgesia and anti-inflammatory activities were investigated using carrageenan-induced paw oedema. Modulation of Cyclooxygenase(COX), inducible nitric oxide synthase(iNOS) and voltage-gated Na+ channels (VGSC) were studied by pre-treatment with substance P,L-arginine and veratrine, respectively. The serum cytokine (TNFα and IL-6) levels were determined using ELISA kits. Bergapten treatment was found to reduce the number of flinchings in formalin-induced hyperalgesia and significantly reduce the number of writhings induced by acetic acid. In addition, paw inflammation induced by carrageenan was significantly reduced. Pre-treatment with substance P,L-arginine and veratrine was found to reverse the analgesic effect of bergapten. Furthermore, increased bergapten treatment was found to significantly inhibit inflammatory cytokines TNFα and IL-6. It is concluded that bergapten has significant analgesic and anti-inflammatory effects in mice, and the plausible modulation of Cyclooxygenase(COX), inducible nitric oxide synthase(iNOS) and Na+ channel pathway may be contributing to the analgesic effect of bergapten. Furthermore, bergapten inhibits the release of inflammatory cytokines TNFα and IL-6.
NMITLI118RT+: A Neuroprotective Lead in Experimental Stroke
Hafsa Ahmad, Sheeba Saji Samuel1, Rakesh Shukla1, Anil Kumar Dwivedi
Divisions of Pharmaceutics and 1Pharmacology, CSIR-Central Drug Research Institute, Lucknow, Uttar Pradesh, India
Address for correspondence: Dr. Hafsa Ahmad, Division of Pharmaceutics, CSIR-Central Drug Research Institute, Lucknow, Uttar Pradesh, India.
Withania somnifera Dunal commonly known as Ashwagandha, is an Indian medicinal plant endowed with numerous beneficial pharmacological properties and has long been used in the traditional systems of medicine. CSIR, India has developed several chemotypes of this plant such as NMITLI-101, NMITLI-118 and NMITLI-128. NMITLI118RT+ represents a standardized concentrated ethanolic extract of a new chemotype of W. somnifera roots characterized by a uniform composition with respect to its secondary metabolites − withanolides. Real-time stability studies on this lead were completed, and different delivery systems of NMITLI118RT+ were prepared to improve its bio-pharmaceutical properties and evaluated for their neuro-protective effects in experimental stroke using the middle cerebral artery occlusion (MCAO) model in rats. It was observed that vesicle-based and complex-based formulations containing NMITLI118RT+ were physically stable and demonstrated better protection over the parent drug in the post-treatment groups. The formulations could augment the beneficial effects of this lead in brain function restoration in ischemia reperfusion injury and present a promising approach in the management of stroke.
Influence of Ethanolic Leaf Extract of Clitoria Ternatea Linn (Nervine Tonic) on Memory Enhancement and Central Cholinergic Activity in Rats
Kriti Sharma, Renu Bist, Ekta Singh Chauhan
Banasthali University, Rajasthan, India
Address for correspondence: Kriti Sharma, Banasthali University, Rajasthan, India.
Clitoria ternatea is a medicinal herb traditionally called as Shankh Pushpi, an Ayurvedic medicine used to promote health. It shows promise in animal models for its memory-enhancing effects and has a wide spectrum of neurological benefits (memory enhancing, anti-depression, anxiolytic and anti-pyretic). Benefits have been seen with its ethanolic component; therefore, multiple bioactive compounds (in regards to brain boosting) are likely. We examined the effectiveness of ethanolic extracts of leaves of C. ternatea at 50 mg/kg and 100 mg/kg doses orally in rats in attenuating electroshock-induced amnesia. Extract at 100 mg/kg dose produced significant memory retention, and the leaves were found to be more effective. To delineate the possible mechanism through which C. ternatea elicits the anti-amnesic effects, we studied its influence on central cholinergic activity by estimating the acetylcholine content of the medulla and cerebellum. Our results suggest that C. ternatea extract increases rat brain acetylcholine content and acetylcholinesterase activity in comparison to cerebro-protective drug, Pyritinol.
A Possible Link Between Spatial Memory Task Performances With Sleep Quality at Extreme Altitude
Koustav Roy, Garima Chauhan, Punita Kumari, Meetu Wadhwa, Sanjeev Kumar, Koushik Ray, Usha Panjwani, Krishna Kishore
Applied Physiology Division, Defence Institute of Physiology and Allied Sciences (DIPAS), Defence Research and Development Organization (DRDO), Timarpur, Delhi, India
Address for correspondence: Koustav Roy, Applied Physiology Division, Defence Institute of Physiology and Allied Sciences (DIPAS), Defence Research and Development Organization (DRDO), Lucknow Road, Timarpur − 110 054, Delhi, India.
Fragmented sleep is one of the common features of high altitude exposure. Hypobaric hypoxia (HH) affects non-rapid eye movement sleep (NREM) followed by alteration in rapid eye movement sleep. Although the reason for altered sleep remains unknown, NREM plays a major role in spatial memory consolidation and retrieval, which is hampered after HH exposure. However, the role of poor quality of sleep on behavioural performance during HH exposure still needs to be understood. Therefore, this study is designed to evaluate the role of NREM2 sleep during HH-induced cognitive decline. We trained our rat in Morris water maze (MWM), and rats were exposed at 25,000 feet altitude continuously for 7 days. Phosphorylated delta sleep-inducing peptide was given as an intervention at a dose of 10 μg/kg/day for enhancement of deep sleep or delta sleep period. We recorded sleep architecture continuously for 7 days by surgically placing the 4ET transmitter into the rat’s peritoneal cavity. Monoamine neurotransmitters were measured by High performance liquid chromatography from the brain stem, cortex, hippocampus and hypothalamus. Tyrosine hydroxylase and glutamic acid decarboxylase expression were determined by flow cytometry from the brain stem region as parameters of sleep quality determination. We observed that HH-exposed rats showed altered behavioural performance with poor quality of sleep. However, rats in the drug-treated group showed better sleep quality (increased NREM2 duration), which may be responsible for increase in the efficiency during MWM task performance. Our study shows a possible link of spatial memory impairment and poor quality of sleep at high altitude.
Development of Novel Animal Model of Cisplatin-Induced Neuropathic Pain in Rats
Malvika Pant, Vivek Jain
Department of Pharmacy, Banasthali University, Banasthali, Rajasthan, India
Address for correspondence: Malvika Pant, Department of Pharmacy, Banasthali University, Banasthali − 304 022, Rajasthan, India.
The current study was designed to develop a refined rat model of cisplatin-induced neuropathic pain at lower dose, so that the lethal effects can subside. Adult female Wistar albino rats were taken for a 21-day study period and were divided in groups of (n = 6) control and treated categories. Neuropathic pain was induced by injecting cisplatin/saline (for control) intraperitoneally at a dose of 2 mg/ml for 2 days in a week for 14 days. The response to various kinematic parameters [splay angle, sciatic functional index (SFI), and tibial functional index (TFI)] and behavioral parameters such as cold allodynia and hot hyperalgesia were measured. The results of the behavioral study exhibited development of neuropathic pain with cisplatin, and it was shown to be maximum at day 11 when compared to the control group. Kinematic parameters such as linear splay increased from 5.2 to 11 cm, angles in both decreased from 82° to 45°, with angles in the right from 74° to 53° and angles in the left from 79° to 56° for control and cisplatin group, respectively. SFI increased to −98 (cisplatin group) from −18 (control group) and TFI augmented up to −108 from −21 for cisplatin and control groups, respectively, which suggest a complete functional loss and, therefore, increased neuropathic pain. Our investigation illustrated the development of a novel rat model of peripheral neuropathic pain produced by cisplatin with high functional deficit and no mortality as compared to older high-dose models that cause high mortality due to nephrotoxicity.
Effect of Hypoxia/Reoxygenation on Cognition: Role of Ion Channels
Manisha Kadam, Nilofar Khan
Defence Institute of Physiology and Allied Science, Timarpur, New Delhi, Delhi, India
Address for correspondence: Manisha Kadam, Defence Institute of Physiology and Allied Science, Timarpur, New Delhi − 110 054, Delhi, India.
Hypoxia is a state of oxygen deficiency in the body, which is sufficient to cause impairment of body function. Hypobaric hypoxia (HBH) causes an imbalance of oxygen availability to tissue, causing severe physiological and psychological dysfunction in humans and other animals. Reoxygenation after hypoxia generally refers to the reintroduction of oxygen to hypoxic tissue at normal sea level atmospheric pressure. The restoration of oxygen after hypoxia is required for recovery but can, by itself, cause tissue damage mainly by formation of free radicals. HBH at high altitude is known to disrupt cognitive functions in humans as well as in animals. So far, the effect of reoxygenation on brain functions such as cognition and its role in different neurological disorders has not been reported yet. Cell membrane is in direct contact with the external environment in both normal and pathophysiologic conditions. Hence, any change in the external environment initiates cellular response in response to external stimuli. Membrane phospholipids and membrane proteins are capable of initiating and mediating such a signal. Membrane proteins, which are susceptible to such activation, include the voltage-dependent ion channels. A number of ion channels play an important role in learning and memory such as small conductance calcium-activated potassium channels (SK) channels (small conductance calcium-activated potassium channels), a subfamily of Ca2+-activated K+ channels. These channels are expressed throughout the central nervous system and are widely distributed in the hippocampus, hence playing a role in cognition and in various neurological disorders such as Alzheimer’s and Parkinson’s. Therefore, on the basis of the aforementioned literature study, we hypothesized the role of small conductance calcium-activated potassium channels (SK) channels in the brain under hypoxia and reoxygenation, which is still an enigma. This study is designed to investigate the time-dependent changes in the expression of small conductance calcium-activated potassium channels (SK) channels during reoxygenation after hypobaric hypoxia exposure. Spraague-Dawley(SD) rats were exposed to HH for 7 days in a simulation chamber at an altitude of 25,000 feet with respective control groups followed by reoxygenation of various time points, namely, 3, 6, 12, 24, 72, and 120 h. Expression of small conductance calcium-activated potassium channels (SK) channels were studied by behavioral, biochemical, and morphological parameters. Neurodegeneration and apoptotic markers were also seen.
Influence of Maternal Malnutrition on Myelination in the Rat Cerebrum at Adulthood and Senility
Mitali Tyagi, A. Srinivasan
Department of Biophysics, All India Institute of Medical Sciences, New Delhi, Delhi, India
Address for correspondence: Mitali Tyagi, Department of Biophysics, All India Institute of Medical Sciences, New Delhi, Delhi, India.
Protein malnutrition is very common throughout the world and is known to impair the development of the nervous system during gestational as well as postnatal period. The objective of the study was to compare the myelin content of the rats following maternal malnutrition with rats on a high-protein diet. During the study, the rats were divided into two groups: low-protein group (LP) and high-protein group (HP). In the LP group, the mothers were switched to 8% protein diet, and the HP mothers were switched to 20% protein diet. The pups were sacrificed postnatally at different time points, and the myelin protein, myelin oligodendrocyte glycoprotein (MOG), was targeted by Luxol Fast Blue staining in addition to immunocytochemistry (fluorescence, anti-MOG). The comparison of myelin in the cerebrum of the rats of the two groups showed that maternal malnutrition results in strong myelination defects. In the first place, it causes hypomyelination. The number of myelinated axons and myelin area are reduced in malnourished rats. In addition, loss of compaction, disturbed cytoarchitectural organization, and axonal damage are evident in the brains of maternally protein malnourished rats in adulthood and senility. A high degree of vacuolization is observed in the myelinated fibers of corpus callosum LP preparations. The most concrete proof of myelin damage in LP-fed rat brains is the presence of demyelinating lesions.
Melatonin Attenuates Traumatic Brain Injury Induced Oxidative Stress in Wistar Rat Brain
Mohd Salman, Suhel Parvez, Heena Tabassum1
Departments of Toxicology and 1Biochemistry, Jamia Hamdard (Hamdard University), Hamdard Nagar, New Delhi, Delhi, India
Address for correspondence: Mohd Salman, Department of Toxicology, Jamia Hamdard (Hamdard University), Hamdard Nagar, New Delhi − 110 062, Delhi, India.
Developing countries are experiencing a socioeconomic burden because of traumatic brain injury (TBI) among the young population. However, only a few studies have focused on traumatic pathological conditions. The aim of this study was to investigate the neuroprotective effect of melatonin (Mel) against TBI in male Wistar rats. Adult Wistar male rats were used and divided into three groups, each having ten animals. Group 2 and group 3 were subjected to cortical injury with control cortical impact. In group 2, normal saline was administered. Mel was administered (10 mg/kg/b.wt.) in group 3 animals after injury. All the experimental animals were sacrificed at 24 h after the injury, and brain tissue was collected for biochemical and apoptosis marker analyses. The oxidative stress parameters such as lipid peroxidation (LPO), glutathione (GSH), superoxide dismutase (SOD), and Bax/Bcl-2 ratio in brain tissue were analyzed. The levels of lipid peroxidation (LPO) and the ratio of Bax/Bcl-2 were significantly reduced in the Mel-treated group when compared to the TBI group. GSH and SOD levels were increased in the Mel-treated group when compared to the TBI. The results of this study showed that Mel ameliorates oxidative stress and neuronal cell death in the early phase of TBI.
Antioxidant Potential of Parkinsonia Aculeata (Root Extracts)
Monika Maan, Bhawna Sati, Divya Yadav, Jai Malik1, Rakesh Yadav
Department of Pharmacy, Banasthali University, Banasthali, Rajasthan, 1University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, India
Address for correspondence: Monika Maan, Department of Pharmacy, Banasthali University, Banasthali − 304 022, Rajasthan, India.
Extraction and pharmacological evaluation of Parkinsonia aculeata roots. Ethyl acetate and n-butanol extract of P. aculeata were evaluated for total phenolic and flavonoid content, as well as antibacterial and antioxidant activity, by four complementary test systems, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydrogen peroxide, reducing power and metal chelating assay. P. aculeata exhibited 2.763 and 1.698 (Gallic acid equivalent (GAE) mg/g) total phenolic content and 0.155 and 0.068 (Quality Evaluation(QE) mg/g) of total flavonoid content for ethyl acetate and n-butanol extracts, respectively. In 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydrogen peroxide and metal chelating assay, IC50 value of ethyl acetate extract was 60.97, 59.51, and 444.09 μg/ml, and IC50 value of n-butanol extract was 236.14, 80.324, and 345.24 μg/ml, respectively. Furthermore, the extract showed inhibitory activity for gram-positive and gram-negative bacteria at different concentrations. The maximum antibacterial activity of chloroform extract was exhibited against B. subtilis at concentration of 16 μg/ml when compared with amoxicillin. The results clearly indicate that roots of P. aculeata are effective in scavenging free radicals and have the potential to be a powerful antioxidant. Thus, the results obtained in this study indicate that root extract of P. aculeata could be considered as a potential source of natural antioxidant, which could be used as an effective source against bacterial diseases.
Neuroprotective Effect of Nordihydroguaiaretic Acid (NDGA) in an In-Vitro Model of Parkinson’s Disease
Pallavi Rane1, Deepaneeta Sarmah1, Shashikala Bhute1, Kiran Kalia1, Pallab Bhattacharya1,2
1Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gandhinagar, Gujarat, India, 2Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
Address for correspondence: Pallavi Rane, Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gandhinagar − 382 355, Gujarat, India.
Parkinson’s disease (PD) is associated with motor dysfunction, and its clinical symptoms are tremors, bradykinesia, muscle rigidity, postural instability, and akinesia. The neuropathological hallmarks of PD are characterized by progressive and profound loss of dopaminergic neurons in the substantia nigra pars compacta. There is also a depletion of postsynaptic dopamine within the striatum along with the presence of protein alpha-synuclein in Lewy bodies and Lewy neurites. Nordihydroguaiaretic acid (NDGA) is a polyphenolic compound that has shown to inhibit αS filament assembly by forming soluble, noncytotoxic, oligomeric complexes with the αS protein. Therefore, we hypothesized that NDGA may have neuroprotective effect in rotenone-induced animal model of PD. First, we performed an in-silico test of NDGA with αS protein molecule and further cell viability assays, antioxidant assays, and immunocytochemistry in in-vitro model of PD. NDGA exhibited good docking score and also showed a promising outcome in in-vitro studies. This hints toward the probable neuroprotective role of NDGA in in-vitro model of PD. On the basis of our preliminary data in in-vitro model, inhibition of αS can be further tested in vivo.
Design and Synthesis of a New Generation of Substituted Hydroxamate Analogs as Histone Deacetylase Inhibitors for the Treatment of Central nervous system (CNS) Disorders
Pooja Mishra, Divya Yadav, Rakesh Yadav
Banasthali University, Jaipur, Rajasthan, India
Address for correspondence: Pooja Mishra, Banasthali University, Tonk, Jaipur − 304 022, Rajasthan, India.
A number of potential approaches have been proposed for the treatment of various Central nervous system (CNS) disorders. Histone deacetylases (HDACs) are enzymes that catalyze the deacetylation of lysine remnants located at the N-terminus of several protein substrates, such as nucleosomal histones. Histone acetylation is an important decisive gene expression. Histone acetyltransferases and HDACs are the two types of enzymes that are primarily amenable for the catalysis of particular lysine residues of histones. Inhibition of HDACs and their different isoforms are broadly reported against brain disorders, such as Alzheimer disorder, Huntington disease, depression, shocking brain injury, post-traumatic stress disorder, anxiety, and dependence. The HDAC inhibitors consist of three defined structural parts of ideal pharmacophore, that is, (a) recognition cap group, (b) hydrophobic linker, and (c) the zinc-binding group. HDACi can be classified into many structural classes including hydroxamates, cyclic peptides, aliphatic acids, and benzamides. Hydroxamic acid constitutes an important class of HDACi with nanomolar activity as reported both in the literature and in patent disclosures. In addition, in-vivo efficacy studies have demonstrated that the hydroxamate class has enormous therapeutic potential. We have synthesized some new compounds of this class considering suberoylanilide hydroxamic acid (vorinostat) as a lead compound. Various heterocyclic motifs were incorporated in the chosen scaffold to obtain molecules with improved therapeutic profile in terms of specificity and potency. Incorporation of spacers such as heteroatoms N and O may provide additional sites of interaction, thus giving the desired selectivity with increased potency. The structures of the newly synthesized compounds were established using nuclear magnetic resonance, ultraviolet and infrared spectroscopy, mass spectrometry, and elemental analysis. The purity of the compounds were checked with the help of Thin layer chromatography(TLC). Microwave-mediated synthesis of the compounds were performed to develop new synthetic techniques to synthesize the designed compounds, which otherwise is a very tedious, time-consuming process. The newly synthesized compounds were evaluated by neurite outgrowth assay, neurite activity, and inhibition of hERG and Human Ether related gene, Cytochrome(CYP) activities. On the basis of in-vitro data, in-vivo activity was performed.
Protective Effects of Roflumilast Against Quinolinic Acid Induced Behavioral and Biochemical Alterations in Experimental Huntington’s Disease
Priyanka Saroj, Yashika Bansal, Raghunath Singh, Sangeeta P. Sah, Anurag Kuhad
Pharmacology Research Laboratory, University Institute of Pharmaceutical Sciences, UGC − Centre of Advanced Study, Panjab University, Chandigarh, India
Address for correspondence: Priyanka Saroj, Pharmacology Research Laboratory, University Institute of Pharmaceutical Sciences, UGC − Centre of Advanced Study, Panjab University, Chandigarh − 160 014, India.
Huntington’s disease (HD) is a autosomal, fatal, and progressive neurodegenerative disorder for which clinically available drugs offer only symptomatic relief. Decreased activity of Cyclic adenosine monophosphate (cAMP) responsive element-binding protein (CREB) is thought to contribute to the death of striatal medium spiny neurons in HD. Therefore, therapies that increase levels of activated CREB and BDNF (brain-derived neurotrophic factor) may be effective in fighting neurodegeneration in HD. Phosphodiesterase-4 (PDE4) has been implicated in various neurological diseases. This study has been structured to investigate the role of roflumilast, a selective PDE4 inhibitor in quinolinic acid (QA)-induced HD symptoms in rats. Rats were administered QA (200 nmol/2 μl saline) intrastriatal bilaterally on 0 day. Roflumilast (0.5 mg/kg, 1 mg/kg, and 1.5 mg/kg, po) each were administered for 21 days once a day. Motor performance was assessed using, open-field, rotarod test, grip strength test, and narrow beam walk test on a weekly basis. On day 22, animals were sacrificed and rat striatum was isolated for biochemical (lipid peroxidation (LPO), Glutathione(GSH), and nitrite), neuroinflammation (TNF-α, IL-6, and IL-1β), and neurochemical analyses. Alterations in mitochondrial complex enzymes (I, II, and IV) in the rat brain were also examined. Treatment with roflumilast reduced brain striatum oxidative and nitrosative (nitrite/nitrate) stress, inflammation, and mitochondrial dysfunctions. These results indicate that PDE4 inhibitor has attenuated QA-induced behavioral and biochemical alterations in experimental Huntington’s disease. Roflumilast was effective in increasing significantly the level of Brain-derived neurotrophic factor( BDNF) in the striatal spiny neurons, which might account for the beneficial effect observed in this model. Therefore, roflumilast can be developed as a potential pharmacotherapeutic adjunct for HD.
2D Quantitative Structural Activity Relation of Hydantoins
Richa Arya, Sarvesh Paliwal, S. P. Gupta
Department of Pharmacy, Banasthali University, Newai, Rajasthan, India
Address for correspondence: Richa Arya, Department of Pharmacy, Banasthali University, Newai, Rajasthan, India.
Alzheimer’s is observed as a fatal disease with complex neuropathology. BACE-1 is a promising molecular target for the development of drugs against Alzheimer’s. Hydantoins have emerged as potent BACE-1 inhibitors. Therefore, with an aim to elucidate the important features responsible for their activity, QSAR studies using stepwise multiple linear regressions, partial least square, and neural network were performed. The Medical Loss Ratio(MLR) and Partial least Square(PLS) models showed good correlation values of 0.80 and 0.75, respectively. The model revealed the importance of the following descriptors: inertia moment 2 length (subs 2), total dipole moment, dipole moment Y component (whole molecule), dipole moment 2 component (subs 2), and molecular refractivity (whole molecule). Thorough study of the reported descriptors revealed that the replacement of the groups at substituent 2 with dipole moment enhancing groups would impose significant positive effect on the overall biological activity. In addition to Medical Loss Ratio(MLR) and Partial least Square(PLS), neural network was also constructed for similar descriptors to evaluate the mode of dependencies of biological activity on obtained descriptors. Using the aforementioned descriptor-based information in future, important BACE-1 inhibitors can be developed that exhibit improved pharmacological characteristics.
Neuroprotective Role of Chlorogenic Acid in MPTP-Induced Parkinson’s Mice Model
Saumitra Sen Singh, Sachchida Nand Rai, Hareram Birla, Walia Zahra, Surya Pratap Singh
Department of Biochemistry, Institute of Science, BHU, Varanasi, Uttar Pradesh, India
Address for correspondence: Saumitra Sen Singh, Department of Biochemistry, Institute of Science, BHU, Varanasi, Uttar Pradesh, India.
Parkinson’s disease (PD) is the second most common neurodegenerative disorder after Alzheimer’s disease. It is characterised by a slow and progressive degeneration of dopaminergic neurons in the substantia nigra. Although dopaminergic neurons in other regions are also affected, they are affected to a lesser extent. The pathology of PD has not yet been fully investigated, although a number of factors contributing to the selective degeneration of substantia nigra, including mitochondrial dysfunction, proteasomal impairment, oxidative stress, excitotoxicity and inflammation, have been extensively studied. Chlorogenic acid (CGA) is a natural polyphenolic compound found in various medicinal plants. Its anti-inflammatory and antioxidant activity has been extensively studied. In our study, we have evaluated the antioxidative and anti-inflammatory activity of CGA using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mice model of PD. MPTP administration caused motor impairment and significant reduction in endogenous antioxidants such as superoxide dismutase and catalase. MPTP challenge-induced lipid peroxidation was evidenced by increased malondialdehyde following disturbance of antioxidant defence. Apart from oxidative stress, MPTP also activated pro-inflammmatory molecules and enhanced inflammatory mediators such as tumor necrosis factor α, nuclear factor-κB (NF-κB) and inducible nitric oxide synthase. The immunofluorescence analysis revealed a significant increase in the number of activated astrocytes accompanied by loss of dopamine neurons in the substantia nigra pars compacta area upon MPTP injection. CGA treatment improved motor impairments, restored antioxidant enzymes, suppressed the production of pro-inflammatory molecules, modulated the astrocytes and microglia activation and blocked the activation of NF-κB. Results of our study suggest that CGA has promising neuroprotective effect against degenerative changes in PD, and the protective effects are mediated through its antioxidant and anti-inflammatory properties. Thus, this work reveals the potential of CGA as a promising drug candidate for PD treatment.
Quantitative Structure–Activity Relationship Analysis of Selective Rho Kinase Inhibitors as Neuroregenerator Agents: Application of Multivariate Statistical Approach
Seema Kesar, Pooja Mishra, Sarvesh Paliwal
Department of Pharmacy, Banasthali Vidyapith, Banasthali, Rajasthan, India
Address for correspondence: Seema Kesar, Department of Pharmacy, Banasthali Vidyapith, Banasthali, Rajasthan, India.
Rho kinases (ROCK), the first Rho effectors to be accounted, are serine/threonine kinases that are important in elementary processes of cell migration, proliferation, and survival. The Rho-ROCK pathway is involved in many aspects of neuronal functions including neurite outgrowth and retraction and becomes an attractive target for the development of drugs for treating neurological disorders; ROCK inhibitors, therefore, have potential for preventing neurodegeneration and stimulating neuroregeneration process. QSAR studies were performed on a series of urea-based derivatives from aniline and benzylamine analogs by using multiple linear regression, partial least square, and feed-forward neural network methods; good model was obtained along with selective descriptors such as inertia moment 2, VAMP polarization YY, VAMP dipole Y component, VAMP dipole Z component, and Kier chiV6 path and having excellent statistical values such as S = 0.38, F = 48.41, r = 0.95, r2 = 0.91, and r2cv = 0.86. Furthermore, external set of molecules was used to confirm the soundness of the model. The findings of the present QSAR analysis will be useful for the design of more potent Rho kinase inhibitors as active neurological agents.
Improvement in Cognitive Function by Small Heterocyclic Moiety
Shashikala Bhute, Pallab Bhattacharya
NIPER, Ahmedabad, Gujarat, India
Address for correspondence: Shashikala Bhute, NIPER, Ahmedabad, Gujarat, India.
Mild cognitive impairment may eventually develop into Alzheimer’s and other types of dementia. Alzheimer’s disease (AD) is a chronic neurodegenerative disorder that manifests into disturbances of cognitive functions such as amnesia. This study is designed to investigate the antiamnesic effect of a small heterocyclic lead compound on behavioral and neurochemical changes in animal model of cognitive impairment and AD. All compounds were designed taking into account Lipinski’s rule of five. We first performed an in-silico testing of the lead compound. The parameters that were analyzed for determining in-silico competence were docking score, 3D pKa predictions, and density function theory studies. The test compound selected exhibited an in-vitro anticholinesterase activity in Ellman’s assay. Preclinical testing is under progress. We plan to perform an acute toxicity testing of the lead compound to find out the optimal dose to be administered. Furthermore, the improvement in cognitive functions will be tested against scopolamine-induced rodent model of amnesia and quinolinic acid induced rodent model of AD. The molecule will also be tested against multiple targets sharing cross-talk in AD. We hypothesize that the lead heterocyclic moiety will show promising therapeutic effects in the animal model of cognitive impairment and AD.
Pharmacological Studies on Neuroprotective Effect of Necrostatin-1 and its Interaction with ω-3 Fatty Acid in MPTP-Induced Parkinson’s Disease
Shipra Kartik, Rishi Pal, Prafulla Chandra Tiwari, Mayank Jain
Department of Pharmacology & Therapeutics, King George’s Medical University, Lucknow, Uttar Pradesh, India
Address for correspondence: Shipra Kartik, Department of Pharmacology & Therapeutics, King George’s Medical University, Lucknow − 226 003, Uttar Pradesh, India.
Parkinson’s disease (PD), a neurodegenerative disorder, is characterized by inflamed dopaminergic neurons. Programmed cell death is a mechanism of cell demise in PD, which includes apoptosis, autophagy, or programmed necrosis (necroptosis), which are types of cell death. The role of RIP kinase inhibitor and ω-3 fatty acid is not known in PD. Therefore, this study is designed to explore the neuroprotective role of RIP kinase inhibitor and their interactions with ω-3 fatty acid. PD was induced in mice by administration of MPTP (20 mg/kg), intraperitoneally. Simultaneously, RIP kinase inhibitor (NEC-1) and ω-3 fatty acid were administered for consecutive 1 week. The animals were observed for the elevated plus maze and open field test for behavioral analysis and oxidative stress markers in brain. Necrostatin-1 (Nec-1) inhibits RIPK1-mediated necroptotic pathway. We observed that MPTP-induced changes in behavioral and locomotor activities were significantly reversed by NEC-1 as well as by ω-3 fatty acid alone and in combination of both. Histopathological and biochemical studies for oxidative markers also substantiate these neuroprotective results. The synergistic effect or the interaction between Nec-1 and ω-3 fatty acid may have better neuroprotective effects on MPTP-induced PD. The signal transduction pathways involved in PD pathogenesis may be mediated trough RIP kinase and antioxidant defence system in the brain. Further studies are needed to confirm and understand neuroprotective role of RIP kinase inhibitors and necroptosis of dopaminergic neuron, which may provide new pharmacotherapeutics for PD patients.
Improved Neuroprotective Potential of Curcumin Via Designing Solid Lipid Nanoparticles
Manu Sharma, Siddhika Pareek
Department of Pharmacy, Banasthali University, Banasthali, Rajasthan, India
Address for correspondence: Manu Sharma, Department of Pharmacy, Banasthali University, Banasthali − 304 022, Rajasthan, India.
Neurodegenerative disorders such Alzheimer’s and Parkinson’s diseases are difficult to treat with current therapies due to complex pathogenesis of disease. Curcumin, plant polyphenol, targets molecular pathways including Nfr-2 and NFKB involved in the modulation of inflammation and oxidative stress. However, its poor solubility, rapid first-pass metabolism, and elimination limit the advancement of the use of curcumin in clinical settings. Therefore, the objective of the study was to prepare curcumin-loaded solid lipid nanoparticles to improve its therapeutic efficacy as neuroprotective agent. Curcumin-loaded solid lipid nanoparticles were prepared by double emulsion solvent method. Various formulation variables such as homogenization speed, drug-polymer ratio, and volume of aqueous phase were optimized. Optimized formulation exhibited high drug load (85.67 ± 6.24%), small particle size (150.45 ± 7.84 nm), good physical stability indicated by zeta potential (−27.34 ± 5.41 mV), and prolonged drug release behavior for 10 h. In-vitro biocompatibility and neuroprotective effect of curcumin and curcumin-loaded nanoparticles were evaluated on SH-SY5Y human neuroblastoma cells. The cellular uptake studies confirmed that higher amount of intracellular localization of curcumin nanoparticles was responsible for improved neuroprotective activity of formulation in peroxide-induced cellular damage.
Expression of Inducible Nitric Oxide Synthase, Cannabinoid Type 1 Receptor, and Somatostatin in the Spinal Cord of Morphine-Tolerant Rats
Shivani Gupta, Mayank Gautam, Pranav Prasoon, Subrata Basu Ray
Department of Anatomy, All India Institute of Medical Sciences, New Delhi, Delhi, India
Address for correspondence: Shivani Gupta, Department of Anatomy, All India Institute of Medical Sciences, New Delhi − 110 029, Delhi, India.
Opioids such as morphine are the most effective drugs for the treatment of cancer pain, but chronic administration produces tolerance, which limits its use. However, the mechanism underlying the development of tolerance is still unknown. It is hypothesized that pain signals are modulated by many neurotransmitters such as nitric oxide, endocannabinoids, and somatostatin at the level of the spinal cord. In turn, these may be adversely affected by repeated administration of morphine. Hence, the aim was to determine the expression of these neurotransmitters in morphine-tolerant rats. Adult male Sprague Dawley rats (N = 66) were implanted with intrathecal catheters under isoflurane anesthesia. These were treated with either physiological saline or morphine (10 μg twice daily) through these catheters for 9 days. Antinociception was tested by the hot-plate apparatus. At the end of this period, rats were sacrificed and perfused with 4% paraformaldehyde solution. The lower lumbar segments (L4–L5) of the spinal cord were processed for immunohistochemical localization of inducible nitric oxide sythase (iNOS), cannabinoid type 1 (CB1) receptor, and somatostatin. Repeated intrathecal administration of morphine produced tolerance as evident from the decrease in the paw withdrawal latency. Immunohistochemistry revealed increased expression of all the three, iNOS, CB1 receptor, and somatostatin, after morphine tolerance in Rexed laminae I–II of the dorsal horn. Incidentally, pain signal from the periphery is carried to these laminae by the Aδ and C nerve fibers. The results suggest that specific neurotransmitters such as somatostatin could play a role in the development of morphine tolerance.
Comparative Studies on Antioxidant Potential of Ethanolic Extract of Leaves of Different Species of Bergenia
Suman Sharma, Jaya Dwivedi1, Swapnil Sharma, Rajani Chauhan
Departments of Pharmacy and 1Chemistry, Banasthali University, Banasthali, Rajasthan, India
Address for correspondence: Suman Sharma, Department of Pharmacy, Banasthali University, Banasthali, Rajasthan, India.
Bergenia, family Saxifragaceae, is popularly known as Pashanbheda (stone breaker) in the Indian system of medicine. Bergenia is a perennial climbing species and is native to India (Kumaon, Himalayas), Afghanistan, south Tibet, Bhutan, etc. Ethanolic extract of leaves of three different Indian varieties of Bergenia (B. ligulata, B. ciliate, and B. stracheyi) were screened for their antioxidant capabilities using different antioxidant assays namely 2,2-diphenyl-1-picrylhydrazyl (DPPH), phosphomolybdenum assay, superoxide assay, singlet oxygen assay, and lipid peroxidation assay. The results of the study revealed that all three species of Bergenia exhibited significant antioxidant activities in different in-vitro screening models. Among all, B. stracheyi showed maximum antioxidant potential as compared to the standards ascorbic acid, α-tocopherol, and butylated hydroxyl toluene.
Neurochemical Exploration in Rodents to Reveal Pathobiology of Epilepsy and Comorbid Depression
Tanveer Singh, Rajesh Kumar Goel
Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala, Punjab, India
Address for correspondence: Tanveer Singh, Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala − 147 002, Punjab, India.
The current study attempts a neurochemical investigation to reveal possible targets for treatment of depression associated with pentylenetetrazole-kindled animals. Kindling was induced in male Swiss albino mice by administering subconvulsive pentylenetetrazole dose (35 mg/kg; i.p.) at an interval of 48 ± 2 h. There were three experimental groups comprising naïve, kindled animals selected after two consecutive, stage 5 seizures and kindled animals selected after five or six consecutive, stage 5 seizures. After the development of kindling, depression was evaluated in all experimental groups using tail suspension as well and forced swim test on day 1 and after a latent period of 7 days. After behavioral evaluations on day 7, animals were sacrificed to harvest their serum and brain. Serum corticosterone levels were estimated in all the experimental groups as marker of dysregulated hypothalamus–pituitary–adrenal axis. Neurochemical alterations (norepinephrine, dopamine, tryptophan, kynurenine, serotonin, glutamate, gamma-aminobutyric acid, and total nitrite levels) were also estimated in cortical and hippocampal areas of the mice brain. The behavioral estimations revealed that after 7 days of latent period, kindled animals selected after five or six consecutive, stage 5 seizures were significantly associated with depression in comparison to kindled animals selected after two consecutive, stage 5 seizures and naïve animals. Neurochemical estimation revealed decreased monoaminergic tone with elevated nitrosative stress and altered glutamate, gamma-aminobutyric acid levels in both cortical and hippocampal areas of depression-associated kindled mice in comparison to kindled and naïve animals. Corticosterone levels were also found to be significantly elevated in the serum of depression associated kindled animals in comparison to kindled and naïve animals. Thus, our study suggested that administration of pharmacological therapies restoring these peculiar biochemical and neurochemical alterations with/without antiepileptic drugs may be explored for comprehensive management of epilepsy and comorbid depression.
Harnessing Neuroprotection and Regeneration in Traumatic Brain Injury: A Translational Computed Neurobiology Platform With Preclinical–Clinical Substantiation
Vikas Pareek, V. P. Subramanyam Rallabandi, Prasun Roy
National Neuro-Imaging Facility, National Brain Research Centre, Manesar, Gurgaon, Haryana, India
Address for correspondence: Vikas Pareek, National Neuro-Imaging Facility, National Brain Research Centre, Manesar, Gurgaon − 122 050, Haryana, India.
Globally, in 5 years, traumatic brain injury (TBI) would become the leading disease burden, after cardiac ischemia and malignant disease, and occurs mainly due to traffic accidents in developing countries (Lancet-Neurology, 11: 651, 2011), with India’s burden as the highest. Although customary clinical management is available, there is much need for newer therapeutic approaches, as currently no treatment adjuncts appreciably improve neurorestoration. We explore the possibility of a neuroinformatics/neuroimaging-aided computational methodology for delineating endogenous neuroprotection or cell proliferation, under internal or external activation (growth factors), as a regenerative approach to TBI. An international cooperation has been initiated by International Neuroinformatics Coordinating Facility (of which India is member), and our study is an investigation from Indian International Neuroinformatics Coordinating Facility (INCF) member-node in concordance with the initiative. Gomp-ex quantitative model for cell growth analysis is employed to assess recovery in human and rodent models with TBI. We particularly considered frontal lobe injuries, the most common TBI type. Using the Gomp-ex quantitative cell growth analysis, we developed a computational formulation of intracranial cell proliferation (gliogenesis, dendritogenesis, and angiogenesis) based on experimental findings, in both preclinical and clinical settings, that is, the adult rodent and adult human systems, postinjury. We analyse the histologically demonstrated frontal migratory channel system of stem cell generated endogenously in the subventricular zone and emanating into cerebral hemispheres, namely lateral cortical migratory channels (rodent) and medial cortical migratory channel (human). We delineate a quantitative formulation to gauge the cellular regeneration intensity with altering age. Nonpaired parametric group analysis of variance with post-hoc pairwise Bonferroni correction was used. We thereby formulated a quantitative model of the progenitor cell formation rate across the channels, undergoing proliferation kinetics. We then validated the formulation using available findings from (i) Magnetic Resonance Imaging (MRI)/neurological investigation of human TBI recovery and (ii) immunohistochemical study of rodent experimental TBI model. In the human case, the patient had a penetrating left frontal injury that destroyed 22% of the right frontal white matter, with recovery monitored weekly. In the rodent experiment, there was 24% injury of the left frontal region, and the enhanced recovery was tracked under defined dose of regeneration-promoting drug, carbamylated erythropoietin. Our computational neurobiology formulation functioned as an in-silico clinical trial and correctly predicted and tracked the recovery endpoints, in both rodent and human systems, within 10% error. A neuroinformatics platform can be thus be explored for translational applicability for traumatic brain injury.
Therapeutic Approach to Remove α-Synuclein Aggregates Through Catechol-Based Compounds in Parkinson’s Disease
Walia Zahra, Sachchida Nand Rai, Hare Ram Birla, Saumitra Sen Singh, Surya Pratap Singh
Department of Biochemistry, Neurobiology Lab, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, India
Address for correspondence: Walia Zahra, Department of Biochemistry, Neurobiology Lab, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, India.
Parkinson’s disease (PD) is a progressive neurodegenerative disease of the central nervous system. The neuronal damage is in specific dopaminergic brain areas, causing devastating symptoms, such as resting tremor, rigidity, and bradykinesia. Although PD’s etiology is unknown, it has been reported that one of the major hallmarks of PD pathogenesis is α-synuclein aggregation in the substantia nigra pars compacta of the mid brain, which could be associated to some pathological processes such as oxidative stress, endoplasmic reticulum stress, impaired protein degradation, and mitochondrial dysfunction. Oxidative stress involves either excessive generation of reactive oxygen species (ROS) or dysfunction of the antioxidant system. The brain is especially vulnerable to the effects of Reactive Oxygen Species(ROS) because of its high oxygen demand and its abundance of peroxidation-susceptible lipid cells. A vital role of α-synuclein in the modulation of dopamine transporter (DAT) function, and disruption of this modulatory process permits increased re-uptake of high levels of intracellular dopamine by DAT, generating Reactive Oxygen Species(ROS) and thus causing profound neurotoxicity, as reported. These days, a lot of emphasis is given on the treatment of this disease using herbal medicines. Several compounds including epigallocatechin gallate and baicalein found in tea polyphenols, N-methylated peptides, and catechol-based compounds have been put forward based on their effectiveness in removing toxic aggregates of α-synuclein either by interacting with them or by disrupting their interactions with other toxic metabolites generated through oxidative stress in vitro; their effects have to be further studied in vivo. Therefore, screening of several Ayurvedic plants for different catechol-based compounds, which can effectively remove the toxic aggregates of α-synuclein, has been planned. Moreover, their role in protein degradation through various pathways can be studied for their efficacy and to be considered for the clinical trials to treat PD.