A mechanistic approach to explore the neuroprotective potential of zonisamide in seizures.

BACKGROUND: Epilepsy, a disease of the brain, is one of the most common serious neurological conditions. It is associated with a group of processes which alter energy metabolism, interrupt cellular ionic homeostasis, cause receptor dysfunction, activate inflammatory cascade, alter neurotransmitter uptake and result in neuronal damage. The increasing knowledge and understanding about the basis of neuronal changes in epilepsy lead to investigate the mechanistic pathway of neuroprotective agents in epilepsy. With this background, the present study is designed to reveal the molecular and biochemical mechanisms involved in the neuroprotective potential of zonisamide in epilepsy. METHODS: Seizure-induced neuronal damage was produced by maximal electroshock seizures in animals. The oxidative stress and neuroinflammatory and apoptotic markers were assessed in the brain tissue of animals. RESULTS AND DISCUSSION: The present findings revealed that zonisamide treatment prevented the development of seizures in animals. Seizures-induced free radicals production and neuroinflammation were markedly ameliorated by zonisamide administration. In conclusion, the present study demonstrated the mechanisms behind the strong neuroprotective potential of zonisamide against seizures by attenuating the oxidative stress, inflammatory cascade and neuronal death associated with progression of seizures. It can be further developed as a neuroprotective agent for epilepsy and other neurodegenerative disorders.

Vaccinium myrtillus ameliorates unpredictable chronic mild stress induced depression: possible involvement of nitric oxide pathway.

Chronic unpredictable stressors can produce a situation similar to clinical depression and such animal models can be used for the preclinical evaluation of antidepressants. Nitric oxide, a secondary messenger molecule, has been implicated in neurotransmission, synaptic plasticity, learning, aggression and depression. Vaccinium myrtillus (bilberry) extract is a potent inhibitor of reactive oxygen/nitrogen species and cytokine production. The present study investigated the role of nitric oxide in the antidepressant action of Vaccinium myrtillus in unpredictable chronic mild stress-induced depression in mice. Animals were subjected to different stress paradigms daily for a period of 21 days to induce depressive-like behavior. Pretreatment with L-arginine significantly reversed the protective effect of bilberry (500 mg/kg) on chronic stress-induced behavioral (immobility period, sucrose preference) and biochemical (lipid peroxidation and nitrite levels; endogenous antioxidant activities) in stressed mice. Furthermore, L-NAME (10 mg/kg) pretreatment with a sub-effective dose of bilberry (250 mg/kg) significantly potentiated the protective effect of bilberry extract. The study revealed that modulation of the nitric oxide pathway might be involved in antidepressant-like effects of Vaccinium myrtillus in stressed mice.

IDO-1 inhibition protects against neuroinflammation, oxidative stress and mitochondrial dysfunction in 6-OHDA induced murine model of Parkinson's disease.

Parkinson's disease (PD), a common neurodegenerative motor disorder characterized by striatal dopaminergic neuronal loss and localized neuroinflammation in the midbrain region. Activation of microglia is associated with various inflammatory mediators and Kynurenine pathway (KP) being one of the major regulator of immune response, is involved in the neuroinflammatory and neurotoxic cascade in PD. In the current study, 1-Methyltryptophan (1-MT), an Indolamine-2,3-dioxygenase-1 (IDO-1) inhibitor was tested at different doses (2.5 mg/kg, 5 mg/kg and 10 mg/kg) for its effect on behavioral parameters, oxidative stress, neuroinflammation, apoptosis, mitochondrial dysfunction, neurotransmitter levels, biochemical and behavioral alterations in unilateral 6-OHDA (3 µg/µL) murine model of PD. The results showed improved locomotion in open field test and motor coordination in rota-rod, reduced oxidative stress, neuroinflammatory markers (TNF-α, IFN-γ, IL-6), mitochondrial dysfunction and neuronal apoptosis (caspase-3). Also, restoration of neurotransmitter levels (dopamine and homovanillic acid) in the striatum and increased striatal BDNF levels were observed. Overall findings suggest that 1-MT could be a potential candidate for further studies to explore its possibility as an alternative in the pharmacotherapy of PD.

A New Therapeutic Approach for Brain Delivery of Epigallocatechin Gallate: Development and Characterization Studies.

BACKGROUND: Blood-brain permeability is the primary concern when dealing with the biodistribution of drugs to the brain in neurological diseases. OBJECTIVE: The purpose of the study is to develop the nanoformulation of Epigallocatechin gallate (EGCG) in order to improve its bioavailability and penetration into the brain. METHODS: EGCG loaded Solid Lipid Nanoparticles (SLNs) have been developed using microemulsification method and pharmacological assessments were performed. RESULTS: Surface morphology and micromeritics analysis showed the successful development of EGCG loaded solid lipid nanoparticles with an average size of 162.4 nm and spherical in shape. In vitro release studies indicated a consistent and slow drug release. Pharmacological evaluation of SLN-EGCG demonstrated a significant improvement in cerebral ischemia-induced memory impairment. CONCLUSION: The results indicate that the EGCG loaded SLNs provide a potential drug delivery system for improved delivery of EGCG to the brain, hence, enhancing its brain bioavailability.

Evaluation of Brain Pharmacokinetic and Neuropharmacodynamic Attributes of an Antiepileptic Drug, Lacosamide, in Hepatic and Renal Impairment: Preclinical Evidence.

The knowledge of pharmacokinetic and pharmacodynamic properties of antiepileptic drugs is helpful in optimizing drug therapy for epilepsy. This study was designed to evaluate the pharmacokinetic and pharmacodynamic properties of lacosamide in experimentally induced hepatic and renal impairment in seizure animals. Hepatic or renal impairment was induced by injection of carbon tetrachloride or diclofenac sodium, respectively. After induction, the animals were administered a single dose of lacosamide. At different time points, maximal electroshock (MES) seizure recordings were made followed by isolation of plasma and brain samples for drug quantification and pharmacodynamic measurements. Our results showed a significant increase in the area under the curve of lacosamide in hepatic and renal impairment groups. Reduced clearance of lacosamide was observed in animals with renal impairment. Along with pharmacokinetic alterations, the changes in pharmacodynamic effects of lacosamide were also observed in all the groups. Lacosamide showed a significant protection against MES-induced seizures, oxidative stress, and neuroinflammatory cytokines. These findings revealed that experimentally induced hepatic or renal impairment could alter the pharmacokinetic as well as pharmacodynamic properties of lacosamide. Hence, these conditions may affect the safety and efficacy of lacosamide.

Antiepileptic drugs in development pipeline: A recent update.

Epilepsy is the most common neurological disorder which significantly affects the quality of life and poses a health as well as economic burden on society. Epilepsy affects approximately 70 million people in the world. The present article reviews the scientific rationale, brief pathophysiology of epilepsy and newer antiepileptic drugs which are presently under clinical development. We have searched the investigational drugs using the key words 'antiepileptic drugs,' 'epilepsy,' 'Phase I,' 'Phase II' and 'Phase III' in American clinical trial registers (clinicaltrials.gov), the relevant published articles using National Library of Medicine's PubMed database, company websites and supplemented results with a manual search of cross-references and conference abstracts. This review provides a brief description about the antiepileptic drugs which are targeting different mechanisms and the clinical development status of these drugs. Besides the presence of old as well as new AEDs, still there is a need of new drugs or the modified version of old drugs in order to make affected people free of seizures. An optimistic approach should be used to translate the success of preclinical testing to clinical practice. There is an urgent need to improve animal models and to explore new targets with better understanding in order to develop the novel drugs with more efficacy and safety.

Potential of metabolomics in preclinical and clinical drug development.

Metabolomics is an upcoming technology system which involves detailed experimental analysis of metabolic profiles. Due to its diverse applications in preclinical and clinical research, it became an useful tool for the drug discovery and drug development process. This review covers the brief outline about the instrumentation and interpretation of metabolic profiles. The applications of metabolomics have a considerable scope in the pharmaceutical industry, almost at each step from drug discovery to clinical development. These include finding drug target, potential safety and efficacy biomarkers and mechanisms of drug action, the validation of preclinical experimental models against human disease profiles, and the discovery of clinical safety and efficacy biomarkers. As we all know, nowadays the drug discovery and development process is a very expensive, and risky business. Failures at any stage of drug discovery and development process cost millions of dollars to the companies. Some of these failures or the associated risks could be prevented or minimized if there were better ways of drug screening, drug toxicity profiling and monitoring adverse drug reactions. Metabolomics potentially offers an effective route to address all the issues associated with the drug discovery and development.

A prospective study to evaluate awareness about medication errors amongst health-care personnel representing North, East, West Regions of India.

BACKGROUND: Medication errors are prevalent in the hospital settings. To ensure the patient safety and provide better health services, medication errors should be curbed. India is still lacking the regulatory system for the control of medication errors. Therefore, a stringent regulatory set up should be established to reduce medication errors. Awareness among the health-care professionals regarding medication errors may be the major factor in the establishment of successful regulatory system. In Indian context, no study has been reported about the awareness of medication errors. Therefore, this study assessed the awareness of the health-care professionals representing North, East and West regions of India about medication errors. These health-care professionals also included the students who were in the final phase of professional courses related to health management. MATERIALS AND METHODS: A questionnaire comprising of 17 questions pertaining to different aspects of medication errors was prepared. Questionnaire was distributed to 456 health-care professionals of various institutes of North, East and West India. Respondents of the questionnaire were restricted to one sitting for answering the entire questionnaire and they were not allowed to consult with anyone for the purpose of answering the questions. Data was compiled and analyzed. RESULTS: It has been found that 18.45%, 39.48%, 14.16%, 27.9% of respondents were having excellent, good, average, poor knowledge respectively regarding the fundamentals of medication error. Knowledge regarding reporting medication errors was excellent in 56.65%, good in 22.53%, average in 09.23% and poor in 11.59% of respondents. CONCLUSION: The outcome of this study may be of great help in drafting the regulatory policies to curb the problem of medication errors.

Drug therapy in autism: a present and future perspective.

Autism is a neurodevelopmental disorder, with a multifactorial etiology, characterized by severe abnormalities in communications, social awareness and skills, and the presence of restrictive and stereotyped patterns of behaviors. It is traditionally considered a "static" encephalopathic disorder without any specific cure and few effective biomedical interventions. There are various factors which are involved in the etiopathogenesis of autism or autism spectrum disorder (ASD) such as impaired immune responses, neuroinflammation, abnormal neurotransmission, oxidative stress, mitochondrial dysfunction, environmental toxins and stressors. The autism is often associated with a number of genetic disorders such as fragile X syndrome, tuberous sclerosis, epilepsy and Down syndrome. The recent approaches to autism treatment included various non-pharmacological and pharmacological therapy such as food supplementation, detoxification, treatment of neuroinflammation, immunologic treatments and psychotropic medications, which are found to be effective in treating various behavioral symptoms of autism. In current practice, there is no curative treatment for autism but the recommended treatment for autism involves educational therapies: speech therapy, sensory integration therapy, auditory therapy. There are classes of different pharmacological agents which are found to be effective in improving behavioral symptoms of ASD such as neurotransmitter reuptake inhibitors (fluoxetine), tricyclic antidepressants (imipramine), anticonvulsants (lamotrigine), atypical antipsychotics (clozapine), acetylcholinesterase inhibitors (rivastigmine), etc. New classes of drugs with novel mechanisms of action should be there so that this disorder will become less prevalent in the future.

Neuropsychopharmacological effect of sesamol in unpredictable chronic mild stress model of depression: behavioral and biochemical evidences.

RATIONALE: A complex relationship exists among stressful situations, body's reaction to stress, and the onset of clinical depression. Chronic unpredictable stressors can produce a situation similar to clinical depression, and such animal models can be used for the preclinical evaluation of antidepressants. Many findings have shown that the levels of proinflammatory cytokines (e.g., TNF-α) and oxidative stress (increased lipid peroxidation, decreased glutathione levels, and endogenous antioxidant enzyme activities) are increased in patients with depression. Sesamol, a phenolic derivative with a methylenedioxy group, is a potent inhibitor of cytokine production as well as an antioxidant. OBJECTIVES: The present study was designed to investigate the effect of sesamol on unpredictable chronic stress-induced behavioral and biochemical alterations in mice. METHODS: Animals were subjected to different stress paradigms daily for a period of 21 days to induce depressive-like behavior. The sucrose preference, immobility period, locomotor activity, memory acquisition, and retention were evaluated. RESULTS: Chronic treatment with sesamol significantly reversed the unpredictable chronic stress-induced behavioral (increased immobility period, reduced sucrose preference), biochemical (increased lipid peroxidation and nitrite levels; decreased glutathione levels, superoxide dismutase and catalase activities), and inflammation surge (serum TNF-α) in stressed mice. CONCLUSION: The study revealed that sesamol exerted antidepressant-like effects in behavioral despair paradigm in chronically stressed mice, specifically by modulating central oxidative-nitrosative stress and inflammation.

Pathobiological targets of depression.

INTRODUCTION: Depression is one of the most prevalent and life-threatening forms of mental illness associated with significant disability and mortality. About 21% of the world's population is affected by depression. AREAS COVERED: The various pathological factors involved in depression are: monoamine hypothesis, neurotransmitter receptor hypothesis, neurotrophic factor hypothesis, hypothalamic-pituitary-adrenal (HPA) dysregulation, oxidative stress, cytokine hypothesis and NO pathway. Recent drug therapies used to treat depression include: selective serotonin re-uptake inhibitors, norepinephrine and dopamine re-uptake inhibitors and several herbal drugs. The present review focuses on recently unraveled pathogenetic hypotheses and therapeutics of mental depression. Moreover, various evaluation models for antidepressants are discussed. EXPERT OPINION: Stress can be considered as a major contributor to the development of depressive disorder due to the dysregulation of HPA axis. Cytokine effects on behavior are believed to be related in part to their effects on neurotransmitter and neuropeptide function, synaptic plasticity and neuroendocrine function. Although there are multiple pathways that are involved in the pathogenesis of depression, the current antidepressants mainly target monoaminergic pathway. However, the therapeutic potential of other pathways is still under investigation. Drugs targeting NO, cytokines and the kynurenine acid pathway might be the drugs of choice in near future.