Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 17 de 17
Filter
Add more filters










Publication year range
1.
Ann Neurosci ; 31(1): 53-62, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38584983

ABSTRACT

Background: Ischemic stroke is one of the prevalent neurodegenerative disorders; it is generally characterized by sudden abruption of blood flow due to thromboembolism and vascular abnormalities, eventually impairing the supply of oxygen and nutrients to the brain for its metabolic needs. Oxygen-glucose deprived conditions provoke the release of excessive glutamate, which causes excitotoxicity. Summary: Recent studies suggest that circulatory angiotensin-II (Ang-II) has an imperative role in initiating detrimental events through binding central angiotensin 1 (AT1) receptors. Insufficient energy metabolites and essential ions often lead to oxidative stress during ischemic reperfusion, which leads to the release of proinflammatory mediators such as interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and cytokines like interleukin-18 (IL-18) and interleukin- 1beta (IL-1ß). The transmembrane glutamate transporters, excitatory amino acid transporter-2 (EAAT-2), which express in astroglial cells, have a crucial role in the clearance of glutamate from its releasing site and convert glutamate into glutamine in normal circumstances of brain physiology. Key Message: During cerebral ischemia, an impairment or dysfunction of EAAT-2 attributes the risk of delayed neuronal cell death. Earlier studies evidencing that angiotensin receptor blockers (ARB) attenuate neuroinflammation by inhibiting the Ang-II/AT1 receptor-mediated inflammatory pathway and that ceftriaxone ameliorates the excitotoxicity-induced neuronal deterioration by enhancing the transcription and expression of EAAT-2 via the nuclear transcriptional factor kappa-B (NF-kB) signaling pathway. The present review will briefly discuss the mechanisms involved in Ang-II/AT1-mediated neuroinflammation, ceftriaxone-induced EAAT-2 expression, and the repurposing hypothesis of the novel combination of ARBs and ceftriaxone for the treatment of cerebral ischemia.

2.
Phytomedicine ; 123: 155205, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37980807

ABSTRACT

BACKGROUND: Cancer is characterized as the leading cause of death, and the susceptibility of cancer cells to develop resistance due to long-term exposure to complementary chemotherapeutic treatment is referred to as multidrug resistance cancer cells (MDRC), which is a significant obstacle in the treatment of malignancies. Since complementary medicine lost its effectiveness, the development of potential alternative and novel therapeutic approaches has been elevated to a top priority in recent years. In this context, a bioactive protein lectin from plant and animal sources exhibits an invaluable source of anticancer agents with vast therapeutic potential. PURPOSE: This manuscript's primary purpose is to enlighten the evidence-based (from 1986 to 2022) possible molecular mechanism of alternative treatment approaches using lectins over the complementary medicines used for cancer treatment. METHODS: The PRISMA rules have been followed properly and qualitative and quantitative data are synthesized systematically. Articles were identified based on Clinical and preclinical reports published on lectin that investigated the in-depth cellular mechanisms, of reverse drug integrative oncology, as a nano-carried targeted delivery. Articles were systematically screened from 1986 to 2022 and selected based on electronic database searches, Medline (PubMed), Google Scholar, Web of Science, Encyclopaedias, Scopus, and ClinicalTrials.gov database. RESULTS: The search turned up 4,212 publications from 38 different nations, of which 170 reference articles were used in our analysis, in 16 combination therapy and their mode of action, and 27 clinical trial studies including dosage and mechanism of action were included. Reports from the 30 lectins belonging to 28 different families have been included. The reversal mechanism of lectin and alternative therapy against MDRC is critically screened and according to a few clinical and preclinical reports, lectin can suppress the overexpressing genes like P-53, EGFR, and P-gp, MRP, and ABC transporter proteins associated with intracellular transportation of drugs. Since, the drug efflux mechanism leads to MDRC, in this phenomenon, lectin plays a key role in reversing the efflux mechanism. Few preclinical reports have mentioned that lectin shows synergism in combination with complementary medicine and as a nano drug carrier helps to deliver to the targeted site. CONCLUSION: We have discussed the alternative therapy using lectin and an in-depth insight into the reversal drug resistance mechanisms to combat MDRC cancer, enhance the efficacy, reduce toxicity and adverse events, and ensure targeted delivery, and their application in the field of cancer diagnosis and prognosis has been discussed. However, further investigation is necessary in drug development and clinical trials which could be helpful to elaborate the reversal mechanism and unlock newer treatment modalities in MDRC cancer.


Subject(s)
Antineoplastic Agents , Neoplasms , Animals , Humans , Drug Resistance, Multiple , Lectins/pharmacology , Lectins/therapeutic use , Drug Resistance, Neoplasm , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Neoplasms/drug therapy
3.
Neurol Sci ; 44(7): 2265-2275, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36870001

ABSTRACT

Parkinson's disease is a complex age-related progressive dopaminergic neurodegenerative disease consistently viewed as a disorder of movement and is characterized by its cardinal motor symptoms. While the motor symptoms and its clinical manifestations are attributed to the nigral dopaminergic neuronal death and basal ganglia dysfunction, studies have subsequently proven that the non-dopaminergic neurons in various brain regions are also additionally involved with the disease progression. Thus, it is now well accepted that the involvement of various neurotransmitters and other ligands accounts for the non-motor symptoms (NMS) associated with the Parkinson's disease. Consequently, this has demonstrated to possess remarkable clinical concerns to the patients in terms of various disability, such impaired to compromised quality of life and increased risk of morbidity and mortality. Currently, available pharmacological, non-pharmacological, and surgical therapeutic strategies neither prevent, arrest, nor reverse the nigral dopaminergic neurodegeneration. Thus, there is an imminent medical necessity to increase patient's quality of life and survival, which in turn decreases the incidence and prevalence of the NMS. The current research article reviews the potential direct involvement of neurotrophin and its mimetics to target and modulate neurotrophin-mediated signal transduction pathways to enlighten a new and novel therapeutic strategy along with the pre-existing treatments for Parkinson's disease and other neurological/neurodegenerative disorders which are associated with the downregulation of neurotrophins.


Subject(s)
Neurodegenerative Diseases , Parkinson Disease , Humans , Nerve Growth Factors , Neurodegenerative Diseases/drug therapy , Quality of Life , Signal Transduction/physiology , Dopamine/metabolism , Dopaminergic Neurons
4.
J Biomol Struct Dyn ; 41(22): 12620-12631, 2023.
Article in English | MEDLINE | ID: mdl-36644856

ABSTRACT

The present study was initiated with PDB selection and validation where 11 acetylcholinesterase (AChE) and 4 N-methyl-D-aspartate receptor (NMDAR) proteins were considered for docking with Rivastigmine and Riluzole respectively. Out of the 15 proteins, selected significant binding was observed for AChE, with 5FPQ, and NMDA receptors with 5I2K. Molecular docking studies of 5FPQ/Rivastigmine complex displayed a binding score of -8.6 kcal/mol, and the predicted inhibitory concentration (Ki) was found to be 31 nM, whereas the 5I2K/Riluzole complex showed a binding score of -9.6 kcal/mol, with an inhibitory concentration (Ki) of 21 nM. Riluzole in complex with 5I2K formed predominant π-π stacking interactions with Tyr144, pi-alkyl interaction with Pro129, and conventional hydrogen bond with Phe130. In contrast, Rivastigmine in a complex with 5FPQ formed a hydrogen bond with Gln413 and pi-alkyl with Pro537. Molecular dynamics simulation study of both complexes 5FPQ/Rivastigmine and 5I2K/Riluzole exhibited stable RMSD, RMSF, Rg, and significant numbers of hydrogen bonds. From free energy landscape (FEL) analysis both complexes were observed to achieve global minima. Overall, molecular docking and MD simulation with subsequent binding free energies studies (MM-PBSA) elucidate the binding conformations and stability of these reprogrammed drugs in the AChE and NMDAR targets. From these in-silico predictions, it can be suggested that both Rivastigmine and Riluzole combination may provide better insights as a starting point combination therapy for the treatment of Alzheimer's disease.Communicated by Ramaswamy H. Sarma.


Subject(s)
Alzheimer Disease , Molecular Dynamics Simulation , Humans , Rivastigmine/pharmacology , Rivastigmine/therapeutic use , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Acetylcholinesterase/chemistry , Receptors, N-Methyl-D-Aspartate/metabolism , Receptors, N-Methyl-D-Aspartate/therapeutic use , Cholinesterase Inhibitors/chemistry , Riluzole/pharmacology , Riluzole/therapeutic use , Molecular Docking Simulation
5.
J Cell Biochem ; 124(3): 359-372, 2023 03.
Article in English | MEDLINE | ID: mdl-36649127

ABSTRACT

Excitotoxicity, depletion of energy metabolites, and ionic imbalance are the major factors involved in neurodegeneration mediated through excitatory amino acid transporter-2 (EAAT-2) dysfunction in ischemic insult. Recent studies have revealed that ceftriaxone expresses EAAT-2 via nuclear transcription factor kappa-B (NF-kB) signaling pathway, stimulation of EAAT-2 expression in the ischemic, and excitotoxic conditions that could provide potential benefits to control neurodegeneration. In this study, we have predicted the in silico model for interaction between NF-kB and EAAT-2 promoter region to rule out the conformational changes for the expression of EAAT-2 protein. Using homology-built model of NF-kB, we identified ceftriaxone-induced conformational changes in gene locus -272 of DNA where NF-kB binding with EAAT-2 promoter region through protein-DNA docking calculation. The interaction profile and conformational dynamics occurred between ceftriaxone predocked and postdocked conformations of NF-kB with DNA employing HADDOCK 2.2 web server followed by 250 ns long all atom explicit solvent molecular dynamics simulations. Both the protein and DNA exhibited modest conformational changes with respect to HADDOCK score, energy terms (desolvation energy [Edesolv ]), van der waal energy (Evdw ), electrostatic energy (Eelec ), restraints energy (Eair ), buried surface area, root mean square deviation, RMSF, radius of gyration, total hydrogen bonds when ceftriaxone pre- and postdocked NF-kB conformations were bound to DNA. Hence, the conformational changes in the C-terminal domain could be the reason for EAAT-2 expression through ceftriaxone specific binding pocket of -272 of DNA.


Subject(s)
Ceftriaxone , NF-kappa B , Ceftriaxone/pharmacology , NF-kappa B/genetics , NF-kappa B/metabolism , Signal Transduction , Neuroglia/metabolism , Promoter Regions, Genetic
6.
Biochem Biophys Res Commun ; 631: 1-8, 2022 11 26.
Article in English | MEDLINE | ID: mdl-36162324

ABSTRACT

Aß cascade hypothesis being considered most evident event in AD pathology and even today it holds good. Dysregulation of catalytic events of Aß regulating enzymes can possibly cause faulty Aß trafficking; inequity of Aß formation and clearance resulting in misfolded protein accumulation, neurodegeneration and cognitive impairment. Many novel approaches have been made on this pathway to discover new molecules, unfortunately couldn't reach the terminal phases of clinical trials. Over decades, studies have been more focused on enzyme chemistry and explored the relationship between structural features and catalytic function of Aß regulating enzymes. However, the modulations of catalytic mechanisms of those enzymes have not been imposed so far to reduce the Aß load. Hence, in this review, we have critically detailed the knowledge of basic structural dynamics and possible catalytic modulations of enzymes responsible for Aß formation and clearance that will impart new perspectives in drug discovery process.


Subject(s)
Alzheimer Disease , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Humans , Proteins
7.
J Ethnopharmacol ; 284: 114827, 2022 Feb 10.
Article in English | MEDLINE | ID: mdl-34774684

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Chandamarutha Chenduram (CC), an Indian traditional Siddha preparation officially recorded in the Siddha formulary of India and its composition are widely used in the Siddha practice of neurological disorders like stroke/paralysis in India. However, the scientific validation and mechanistic evidence is lacking and yet to be elucidated. AIM OF THE STUDY: To establish the scientific evidences and to explore the possible neuroprotective mechanism of CC in cerebral ischemia. MATERIALS AND METHODS: Chemical standardization of the CC was performed using atomic absorption spectroscopy and gravimetric analysis. Acute toxicity study for CC in mice was performed in accordance with OECD 423 guidelines. CC (5 mg/kg) and CC (10 mg/kg) were investigated in bilateral common carotid occlusion (BCCAo) model in mice. After, behavioral assessments, the brain samples were collected and the hippocampus region was micro-dissected for neurotransmitter, neurobiochemicals and inflammatory cytokines estimation. The excitatory amino acid transporter-2 (EAAT-2) expressions was analyzed by RT-PCR to understand the possible molecular mechanism. In addition, hematoxylin and eosin staining of CA1 hippocampal brain region was performed to support the neuroprotective effect of CC in ischemic condition. RESULTS: Chemical standardization analysis showed that CC has acceptable range of mercury (0.82 ppm) and elemental sulphur (11% w/w). Also, other heavy metal limits were found to be less or not detectable. Toxicity study also evidenced the safety profile of CC. CC has significantly reversed the behavioral dysfunctions (p < 0.001) in global ischemic mice. Treatment with CC has attenuated the excitatory neurotransmitter glutamate, lipid peroxide, nitric oxide, cytokines (IL-1ß, TNF-α) (p < 0.001) and increased the antioxidant enzymes (SOD, CAT, GSH) and EAAT-2 expression level (p < 0.001) in ischemic brain. The hematoxylin and eosin staining in CA1 region of hippocampus also evidence the neuroprotective effect exhibited by CC. CONCLUSIONS: Treatment with CC has exhibited dose dependent effect and CC10 has shown significant protective effect in comparison to CC5 in most of the parameters studied. CC prevented further degeneration of neurons in cerebral ischemic mice through ameliorating inflammatory cytokines and oxy-radicals mediated EAAT-2 dysfunction and subsequent excitotoxicity in neurons.


Subject(s)
Cytokines/metabolism , Excitatory Amino Acid Transporter 2/metabolism , Medicine, Ayurvedic , Neurons/drug effects , Neuroprotective Agents/pharmacology , Reactive Oxygen Species/metabolism , Animals , Behavior, Animal/drug effects , Cytokines/genetics , Excitatory Amino Acid Transporter 2/genetics , Female , Locomotion/drug effects , Male , Mice , Neuroprotective Agents/chemistry , Oxidative Stress/drug effects
8.
Biochem Biophys Res Commun ; 587: 58-62, 2022 01 08.
Article in English | MEDLINE | ID: mdl-34864547

ABSTRACT

Advancements in brain imaging techniques have emerged as a significant tool in detecting Alzheimer's disease (AD) progression. The complicated cascade of AD progression can be detected using radio imaging, especially with Positron emission tomography (PET). The review focus on recently introduced investigational PET tracers targeting neurofibrillary tau aggregates found typically in AD. Herein, we also address the use of different PET tracers and the clinical implementation of established and newer generation tracers. This review also intends to discuss the importance of several PET radiotracers and challenges in PET imaging.


Subject(s)
Alzheimer Disease/diagnostic imaging , Hippocampus/diagnostic imaging , Prefrontal Cortex/diagnostic imaging , Radioisotopes/chemistry , Radiopharmaceuticals/chemistry , Alzheimer Disease/pathology , Amyloid beta-Peptides/analysis , Amyloid beta-Peptides/chemistry , Disease Progression , Hippocampus/pathology , Humans , Neurofibrillary Tangles/pathology , Neurofibrillary Tangles/ultrastructure , Positron-Emission Tomography/methods , Prefrontal Cortex/pathology , Protein Aggregates , Radioisotopes/administration & dosage , Radioisotopes/classification , Radiopharmaceuticals/administration & dosage , Radiopharmaceuticals/classification , tau Proteins/analysis , tau Proteins/chemistry
9.
Bioorg Chem ; 117: 105462, 2021 12.
Article in English | MEDLINE | ID: mdl-34753059

ABSTRACT

Biginelli 1,4-dihydropyrimidines are extensively screened for their potential anticancer activity in the last decade. In this context, a series of Biginelli 1,4-dihydropyrimidines were designed and synthesised using PTSA as an efficient catalyst. The synthesised 1,4-dihydropyrimidines were screened for their anticancer activity against MCF-7 breast cancer cells by measuring cytotoxicity. The compounds exhibited activity ranging from weak to significant in terms of percentage cytotoxicity which is proportional to the anticancer activity. Amongst the screened compounds, compounds 4, 6 and 8 exhibited potential anticancer activity. Furthermore, CoMSIA studies were performed to derive the structure activity relationships in a 3D grid space by plotting experimental vs predicted cytotoxic activities. We have an opinion that, this developed model helps us in future to develop more potential 1,4-dihydropyrimidines for their cytotoxicity or anticancer activity.


Subject(s)
Antineoplastic Agents/pharmacology , Drug Design , Pyrimidines/pharmacology , Quantitative Structure-Activity Relationship , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Line , Cell Proliferation/drug effects , Cell Survival/drug effects , Chlorocebus aethiops , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Pyrimidines/chemical synthesis , Pyrimidines/chemistry
10.
ACS Chem Neurosci ; 12(13): 2261-2272, 2021 07 07.
Article in English | MEDLINE | ID: mdl-34125534

ABSTRACT

Understanding various aspects of Parkinson's disease (PD) by researchers could lead to a better understanding of the disease and provide treatment alternatives that could significantly improve the quality of life of patients suffering from neurodegenerative disorders. Significant progress has been made in recent years toward this goal, but there is yet no available treatment with confirmed neuroprotective effects. Recent studies have shown the potential of PPARγ agonists, which are the ligand activated transcriptional factor of the nuclear hormone superfamily, as therapeutic targets for various neurodegenerative disorders. The activation of central PGC-1α mediates the potential role against neurogenerative diseases like PD, Huntington's disease, Alzheimer's disease, and amyotrophic lateral sclerosis. Further understanding the mechanism of neurodegeneration and the role of glitazones in the activation of PGC-1α signaling could lead to a novel therapeutic interventions against PD. Keeping this aspect in focus, the present review highlights the pathogenic mechanism of PD and the role of glitazones in the activation of PGC-1α via PPARγ for the treatment of neurodegenerative disorders.


Subject(s)
Neurodegenerative Diseases , Parkinson Disease , Thiazolidinediones , Humans , Neurodegenerative Diseases/drug therapy , PPAR gamma , Parkinson Disease/drug therapy , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , Quality of Life
11.
Mini Rev Med Chem ; 21(12): 1457-1464, 2021.
Article in English | MEDLINE | ID: mdl-33663364

ABSTRACT

The transcriptional factor PPAR-γ belongs to the nuclear receptor family, which has become a potential therapeutic target for several neurodegenerative diseases and metabolic disorders. Interestingly, PPAR-γ has been reported to have beneficial effects in various chronic neurological conditions via upregulation of its transcriptional co-activator PGC-1α and followed by regulation of multiple molecular events. Although several factors contribute to the progression of neurodegeneration, the dysfunction of PGC-1α expression is primarily interlinked with the pathogenesis of major neurodegenerative diseases. This review gives an insight that ligand-dependent activation of PPAR-γ by glitazones could initiate the structural conformational changes of the secondary proteins, thus recruiting the PGC-1α to form a stable regulatory complex that hampers the various molecular pathways contributing to neurodegeneration. The promising outcomes of the preliminary in silico studies included in this review support that PPAR-γ dependent activation of central PGC-1α signaling by novel glitazones is an encouraging strategy to enhance the oxy-radicals detoxifying system, antiinflammatory responses, and mitochondrial biogenesis required for neuroprotection in various neurodegenerative conditions.


Subject(s)
Neuroprotective Agents/pharmacology , PPAR gamma/metabolism , Thiazolidinediones/pharmacology , Animals , Humans
12.
J Pharmacol Toxicol Methods ; 106: 106932, 2020.
Article in English | MEDLINE | ID: mdl-33091537

ABSTRACT

Alzheimer's disease (AD) is regarded as one of the significant health burdens, as the prevalence is raising worldwide and gradually reaching to epidemic proportions. Consequently, a number of scientific investigations have been initiated to derive therapeutics to combat AD with a concurrent advancement in pharmacological methods and experimental models. Whilst, the available experimental pharmacological approaches both in vivo and in vitro led to the development of AD therapeutics, the precise manner by which experimental models mimic either one or more biomarkers of human pathology of AD is gaining scientific attentions. Caenorhabditis elegans (C. elegans) has been regarded as an emerging model for various reasons, including its high similarities with the biomarkers of human AD. Our review supports the versatile nature of C. elegans and collates that it is a well-suited model to elucidate various molecular mechanisms by which AD therapeutics elicit their pharmacological effects. It is apparent that C. elegans is capable of establishing the pathological processes that links the endoplasmic reticulum and mitochondria dysfunctions in AD, exploring novel molecular cascades of AD pathogenesis and underpinning causal and consequential changes in the associated proteins and genes. In summary, C. elegans is a unique and feasible model for the screening of anti-Alzheimer's therapeutics and has the potential for further scientific exploration.


Subject(s)
Alzheimer Disease/drug therapy , Caenorhabditis elegans/genetics , Alzheimer Disease/genetics , Animals , Animals, Genetically Modified , Caenorhabditis elegans Proteins/genetics , Disease Models, Animal , Drug Evaluation, Preclinical/methods , Feasibility Studies , Humans
13.
Front Neurosci ; 14: 530148, 2020.
Article in English | MEDLINE | ID: mdl-33100954

ABSTRACT

The present study has planned to evaluate the neuroprotective activity of two novel glitazones in a neuroinflammatory rat model. Two novel glitazones were selected from an in-house virtual library of glitazones based on their docking scores against peroxisome proliferator-activated receptor-gamma (PPAR-γ) protein and other parameters studied in in silico computational studies. Initially, an acute oral toxicity study was carried out for glitazones in rats to assess the toxicity profile and to determine the therapeutic range for neuroprotective evaluation. Prior to induction of neuroinflammation, the treatments with glitazones (G1 and G2) and standard pioglitazone were made for four consecutive days to respective groups. On the fifth day, the neuroinflammation was induced by intracerebroventricular (ICV) administration of lipopolysaccharides (LPS) (2 µg/µl) using stereotaxic apparatus. After 7 days, the rats were subjected to behavioral assessment followed by neurobiochemical evaluation and histopathological studies. The pre-treatment with glitazones at two dose levels (15 and 30 mg/kg) has significantly reversed behavioral dysfunctions. Glitazones have shown significant reduction in the levels of LPO, NO, TNF-α, and IL-1ß and also increased the levels of antioxidant enzymes such as SOD, CAT, and GSH in the brain of LPS-administered rats. The neuroprotection exhibited by two novel glitazones is comparable with standard pioglitazone. The PPAR-γ-dependent amelioration of cytokines and oxy-radicals released by novel glitazones during neuroinflammatory conditions may be attributed to the reversal of behavioral dysfunctions through preventing the degeneration of neurons in major regions of the brain.

14.
Neurochem Int ; 140: 104814, 2020 11.
Article in English | MEDLINE | ID: mdl-32758586

ABSTRACT

Peroxisome proliferator-activated receptor gamma (PPAR-γ) is one of the ligand-activated transcription factors which regulates a number of central events and considered as a promising target for various neurodegenerative disease conditions. Numerous reports implicate that PPAR-γ agonists have shown neuroprotective effects by regulating genes transcription associated with the pathogenesis of neurodegeneration. In regards, this review critically appraises the recent knowledge of PPAR-γ receptors in neuroprotection in order to hypothesize potential neuroprotective mechanism of PPAR-γ agonism in chronic neurological conditions. Of note, the PPAR-γ's interaction dynamics with PPAR-γ coactivator-1α (PGC-1α) has gained significant attention for neuroprotection. Likewise, a plethora of studies suggest that the PPAR-γ pathway can be actuated by the endogenous ligands present in the CNS and thus identification and development of novel agonist for the PPAR-γ receptor holds a vow to prevent neurodegeneration. Together, the critical insights of this review enlighten the translational possibilities of developing novel neuroprotective therapeutics targeting PPAR-γ for various neurodegenerative disease conditions.


Subject(s)
Neurodegenerative Diseases/metabolism , Neurodegenerative Diseases/prevention & control , Neuroprotection/physiology , PPAR gamma/agonists , PPAR gamma/metabolism , Animals , Humans , Mitochondria/genetics , Mitochondria/metabolism , Neurodegenerative Diseases/genetics , Oxidative Stress/physiology , PPAR gamma/genetics , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/genetics , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism
15.
Med Hypotheses ; 142: 109794, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32413698

ABSTRACT

Excitatory amino acid transporter-2 (EAAT-2) protein localized in the membrane of glial cells are responsible for the clearance of glutamate in synapse and it plays a key role among the five glutamate transporters (EAATs) in regulating synaptic transmission and preventing excitotoxicity in neurons. EAAT-2 dysfunction has been associated with the neuropathology of Alzheimer's disease (AD). Impairment of EAAT-2 transporter function results excess accumulation of glutamate in synaptic cleft that acts on post-synaptic glutaminergic receptors excessively resulting in influx of Na+ and Ca2+ ions into the neurons. This triggers excitotoxicity in post-synaptic neurons by activating apoptotic or necrotic pathways causing neurodegeneration in AD. The compounds that increase the EAAT-2 activity may have therapeutic potential for neuroprotection in AD. The positive allosteric site activation of EAAT-2 represents a promising entry point for the identification of novel pharmacological compounds for the management of neurodegenerative conditions involving glutamate-mediated excitotoxicity. We hypothesize, therefore, that the positive allosteric activators may enhance glutamate clearance from the synaptic cleft by promoting orthosteric binding of glutamate ligand in EAAT-2 transporter protein and attenuate the excitotoxicity in neurons and prevent the disease progression of AD.


Subject(s)
Alzheimer Disease , Excitatory Amino Acid Transporter 2 , Allosteric Regulation , Alzheimer Disease/drug therapy , Excitatory Amino Acid Transporter 2/metabolism , Glutamic Acid , Humans , Neuroglia
16.
Neurotox Res ; 37(3): 508-524, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31782098

ABSTRACT

In the present study, two structurally diverse novel glitazones were designed and synthesized for activation of central PGC-1α signaling through stimulation of PPAR-γ receptor. The functional interaction between PGC-1α and PPAR-γ is a key interaction in the normal physiology of neuroprotective mechanism. Therefore, activation of PPAR-γ-dependent PGC-1α co-activator signaling could be an effective strategy to exhibit neuroprotection in several neurodegenerative disorders like Alzheimer's disease, Parkinson's disease, and cerebral ischemia. As part of rational design, analogs were designed manually based on principles of bioisosterism, followed by virtually screened using docking to predict the mode of interaction of compound towards the binding site and molecular dynamic simulation to observe the structural changes that occur during compound interaction with active site. The designed two glitazones (G1, G2) were synthesized and structurally analyzed. As part of evaluation, synthesized glitazones were subjected for preliminary neuroprotective evaluation in Lipopolysaccharide (LPS) intoxicated SH-SY5Y neuroblastoma cells. The results indicate that pre-treatment with synthesized glitazones have increased the percentage cell viability, protected the cell morphology, and decreased the release of pro-inflammatory cytokines (IL-1ß, TNF-α), lipid peroxide (LPO), and nitric oxide (NO) level in LPS intoxicated SH-SY5Y cells. Interestingly, among the two glitazones, G2 has shown significant neuroprotection in comparison to G1 and neuroprotective effect exerted by G2 was similar and comparable with the standard pioglitazone. Altogether, neuroprotection exhibited by this non-thiazolidione-based glitazones during neuroinflammatory conditions may be attributed to the activation of central PGC-1α signaling via PPAR-γ receptor.


Subject(s)
Drug Design , Neurodegenerative Diseases/drug therapy , Neuroprotective Agents/administration & dosage , Neuroprotective Agents/chemical synthesis , PPAR gamma/metabolism , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism , Thiazolidinediones/administration & dosage , Thiazolidinediones/chemical synthesis , Cell Line, Tumor , Cell Survival/drug effects , Encephalitis/complications , Encephalitis/metabolism , Humans , Interleukin-1beta/metabolism , Lipopolysaccharides/administration & dosage , Molecular Dynamics Simulation , Neurodegenerative Diseases/complications , Neurodegenerative Diseases/metabolism , Tumor Necrosis Factor-alpha/metabolism
17.
Behav Pharmacol ; 27(7): 615-22, 2016 10.
Article in English | MEDLINE | ID: mdl-27564990

ABSTRACT

Glutamate, an excitatory neurotransmitter in the brain, produces excitotoxicity through its agonistic action on postsynaptic N-methyl-D-aspartate receptor, resulting in neurodegeneration. We hypothesized that the administration of low doses of glutamate in cerebral ischemia could attenuate the excitotoxicity in neurons through its autoreceptor regulatory mechanism, and thereby control neurodegeneration. To test the hypothesis, the effect of L-glutamic acid (L-GA) 400 µmol/l/kg was evaluated in a bilateral common carotid artery occlusion-induced global ischemic mouse model. Memantine was used as a positive control. Global ischemia in mice was induced by occlusion of both the common carotid artery (bilateral common carotid artery occlusion) for 20 min, followed by reperfusion injury. L-GA was infused slowly through the tail vein 30 min before the surgery and every 24 h thereafter until the end of the experiment. The time-dependent change in cerebral blood flow was monitored using a laser Doppler image analyzer. The neurotransmitters glutamate and γ-aminobutyric acid (GABA) and the neurobiochemicals ATP, glutathione, and nitric oxide were measured in the different regions of brain at 0, 24, 48, and 72 h after reperfusion injury. L-GA increased locomotor activity, muscle coordination, and cerebral blood flow in ischemic mice at 72 h after ischemic insult. L-GA reduced glutamate levels in the cortex, striatum, and hippocampus at 72 h, whereas GABA levels were elevated in all three brain regions studied. Further, L-GA elevated glutathione levels and attenuated nitric oxide levels, but failed to restore ATP levels 72 h after ischemia-reperfusion. We conclude that the gradual reduction of glutamate along with elevation of GABA in different brain regions could have contributed toward the neuroprotective effect of L-GA. Hence, a slow infusion of a low dose of L-GA could be beneficial in controlling excitotoxicity-induced neurodegeneration following ischemia.


Subject(s)
Brain Ischemia/prevention & control , Glutamic Acid/pharmacology , Neuroprotective Agents/pharmacology , gamma-Aminobutyric Acid/metabolism , Animals , Brain/drug effects , Brain/pathology , Brain Ischemia/pathology , Carotid Artery, Common/pathology , Disease Models, Animal , Dose-Response Relationship, Drug , Glutamic Acid/administration & dosage , Glutamic Acid/metabolism , Glutathione/metabolism , Male , Memantine/pharmacology , Mice , Neuroprotective Agents/administration & dosage , Nitric Oxide/metabolism , Receptors, N-Methyl-D-Aspartate/metabolism , Reperfusion Injury/drug therapy , Time Factors
SELECTION OF CITATIONS
SEARCH DETAIL
...