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1.
PLoS Pathog ; 20(10): e1012615, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39392861

RESUMO

In hepatitis C virus (HCV) infection, CD4+ and CD8+ T cells are crucial for viral control. However, a detailed understanding of the kinetic of CD4+ T cell help and its role in the generation of different CD8+ T cell subsets during acute infection is lacking. The absence of a small HCV animal model has impeded mechanistic studies of hepatic antiviral T cell immunity and HCV vaccine development. In this study, we used a recently developed HCV-related rodent hepacivirus infection mouse model to investigate the impact of CD4+ T cell help on the hepatic CD8+ T cell response and viral clearance during hepacivirus infection in vivo. Our results revealed a specific kinetic of CD4+ T cell dependency during acute infection. Early CD4+ T cell help was essential for CD8+ T cell priming and viral clearance, while CD4+ T cells became dispensable during later stages of acute infection. Effector CD8+ T cells directly mediated timely hepacivirus clearance. An analysis of hepatic CD8+ T cells specific for two different viral epitopes revealed the induction of subsets of liver-homing CD103+CD49a+ and CD103-CD49a+ effector CD8+ T cells with elevated IFN-γ and TNF-α production. CD103+CD49a+ T cells further persisted as tissue-resident memory subsets. A lack of CD4+ T cell help and CD40L-CD40 interactions resulted in reduced effector functions and phenotypical changes in effector CD8+ T cells and a specific loss of the CD103+CD49a+ subset. In summary, our study shows that early CD4+ T cell help through CD40L signaling is essential for priming functional effector CD8+ T cell subsets, including unique liver-homing subsets, and hepacivirus clearance.


Assuntos
Antígenos CD , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Hepacivirus , Hepatite C , Cadeias alfa de Integrinas , Fígado , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD4-Positivos/imunologia , Camundongos , Fígado/imunologia , Fígado/virologia , Hepacivirus/imunologia , Antígenos CD/metabolismo , Antígenos CD/imunologia , Hepatite C/imunologia , Hepatite C/virologia , Cadeias alfa de Integrinas/metabolismo , Cadeias alfa de Integrinas/imunologia , Camundongos Endogâmicos C57BL , Integrina alfa1/imunologia , Integrina alfa1/metabolismo , Modelos Animais de Doenças , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
2.
Front Pharmacol ; 15: 1382876, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39323638

RESUMO

Introduction: Lectins are carbohydrate-binding proteins that are extremely selective for sugar groups in the other molecules. As a result, they perform a variety of roles in biological processes involving cell, carbohydrate, and protein recognition at the cellular and molecular levels. Because lectins can bind to carbohydrates, they may play a role in determining the rate of carbohydrate digestion. They also bind to some proteins involved in diabetes mellitus (DM) pathophysiology. The present review aims to summarize the efficiency of lectins from different sources as potential antihyperglycemic agents. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were employed for the drafting. In this regard, published scientific articles on the effects of different lectins on blood glucose (BG), glucose tolerance, hormonal effects, carbohydrate-digesting enzymes, oxidative stress, and insulin production process were collected from reputed journals using electronic databases. Furthermore, the toxicity effects of lectins from different sources were collected. A specific keyword search was completed to collect numerous articles with unique experimental designs and significant results. This was followed by the selection of the requisite articles based on the criteria designed by the authors. Data extraction was based on the common research elements included in the articles. Results and Discussion: Of 13 identified studies, 11 studies were considered after double screening based on the inclusion criteria. All 11 pharmacological investigations were considered for review. Subsequent studies reflected on the pharmacological properties of lectins on the levels of BG, oxidative stress, ß-cell proliferation, insulin resistance, inhibition of carbohydrate digesting enzymes, body weight, food and water intake, lipid profile, and other parameters. This review highlights lectins as potential anti-diabetic agents. Conclusion: However, due to limited research, systematic evaluation is recommended for their development and promotion as effective potential antihyperglycemic agents. The clinical efficacy and safety of lectins against diabetes mellitus must also be evaluated.

3.
Glia ; 72(9): 1707-1724, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38864289

RESUMO

Astrocytes play an essential role in regulating synaptic transmission. This study describes a novel form of modulation of excitatory synaptic transmission in the mouse hippocampus by astrocytic G-protein-coupled receptors (GPCRs). We have previously described astrocytic glutamate release via protease-activated receptor-1 (PAR1) activation, although the regulatory mechanisms for this are complex. Through electrophysiological analysis and modeling, we discovered that PAR1 activation consistently increases the concentration and duration of glutamate in the synaptic cleft. This effect was not due to changes in the presynaptic glutamate release or alteration in glutamate transporter expression. However, blocking group II metabotropic glutamate receptors (mGluR2/3) abolished PAR1-mediated regulation of synaptic glutamate concentration, suggesting a role for this GPCR in mediating the effects of PAR1 activation on glutamate release. Furthermore, activation of mGluR2/3 causes glutamate release through the TREK-1 channel in hippocampal astrocytes. These data show that astrocytic GPCRs engage in a novel regulatory mechanism to shape the time course of synaptically-released glutamate in excitatory synapses of the hippocampus.


Assuntos
Astrócitos , Região CA1 Hipocampal , Ácido Glutâmico , Camundongos Endogâmicos C57BL , Receptor PAR-1 , Receptores de Glutamato Metabotrópico , Sinapses , Animais , Receptores de Glutamato Metabotrópico/metabolismo , Astrócitos/metabolismo , Ácido Glutâmico/metabolismo , Sinapses/metabolismo , Região CA1 Hipocampal/metabolismo , Receptor PAR-1/metabolismo , Camundongos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Masculino , Transmissão Sináptica/fisiologia , Transmissão Sináptica/efeitos dos fármacos , Canais de Potássio de Domínios Poros em Tandem/metabolismo
4.
Obstet Med ; 17(1): 28-35, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38655195

RESUMO

Background: With the emergence of the coronavirus 2019 (COVID-19) pandemic, it was essential to determine the impact of this disease on pregnant women and neonatal outcomes. In this study, we present a series of nine cases of pregnant women with COVID-19 disease requiring intensive care unit (ICU) admission. Methods: We retrospectively collected clinical data of pregnant women with COVID-19 disease admitted to ICU between September 2020 and September 2021. Results: Most common presenting symptom was cough. Two patients had no respiratory symptoms at presentation. Five of the nine patients required invasive mechanical ventilation. Seven patients required caesarean section, four of whom delivered preterm. There were no maternal or neonatal deaths. Conclusions: Although maternal and neonatal outcomes reported in our study are encouraging, it is imperative to emphasize the importance of an individualized, multidisciplinary approach, and good healthcare infrastructure for optimal management of this group of patients.

5.
J Extracell Vesicles ; 13(4): e12439, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38647111

RESUMO

Our previous findings demonstrated that astrocytic HIF-1α plays a major role in HIV-1 Tat-mediated amyloidosis which can lead to Alzheimer's-like pathology-a comorbidity of HIV-Associated Neurocognitive Disorders (HAND). These amyloids can be shuttled in extracellular vesicles, and we sought to assess whether HIV-1 Tat stimulated astrocyte-derived EVs (ADEVs) containing the toxic amyloids could result in neuronal injury in vitro and in vivo. We thus hypothesized that blocking HIF-1α could likely mitigate HIV-1 Tat-ADEV-mediated neuronal injury. Rat hippocampal neurons when exposed to HIV-1 Tat-ADEVs carrying the toxic amyloids exhibited amyloid accumulation and synaptodendritic injury, leading to functional loss as evidenced by alterations in miniature excitatory post synaptic currents. The silencing of astrocytic HIF-1α not only reduced the biogenesis of ADEVs, as well as amyloid cargos, but also ameliorated neuronal synaptodegeneration. Next, we determined the effect of HIV-1 Tat-ADEVs carrying amyloids in the hippocampus of naive mice brains. Naive mice receiving the HIV-1 Tat-ADEVs, exhibited behavioural changes, and Alzheimer's 's-like pathology accompanied by synaptodegeneration. This impairment(s) was not observed in mice injected with HIF-1α silenced ADEVs. This is the first report demonstrating the role of amyloid-carrying ADEVs in mediating synaptodegeneration leading to behavioural changes associated with HAND and highlights the protective role of HIF-1α.


Assuntos
Astrócitos , Vesículas Extracelulares , HIV-1 , Hipocampo , Subunidade alfa do Fator 1 Induzível por Hipóxia , Neurônios , Vesículas Extracelulares/metabolismo , Animais , Astrócitos/metabolismo , Camundongos , Ratos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , HIV-1/metabolismo , Hipocampo/metabolismo , Neurônios/metabolismo , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Humanos , Transtornos Neurocognitivos/metabolismo , Transtornos Neurocognitivos/etiologia , Infecções por HIV/metabolismo , Infecções por HIV/complicações , Masculino , Complexo AIDS Demência/metabolismo
6.
Br J Pharmacol ; 181(9): 1421-1437, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38044332

RESUMO

BACKGROUND AND PURPOSE: Chronic pain remains a major clinical problem that needs effective therapeutic agents. Glutamate delta 1 (GluD1) receptors and the protein cerebellin 1 (Cbln1) are down-regulated in the central amygdala (CeA) in models of inflammatory and neuropathic pain. One treatment with Cbln1, intracerebroventricularly (ICV) or in CeA, normalized GluD1 and reduced AMPA receptor expression, resulting in lasting (7-10 days) pain relief. Unlike many CNS-targeting biological agents, the structure of Cbln1 suggests potential blood-brain barrier penetration. Here, we have tested whether systemic administration of Cbln1 provides analgesic effects via action in the CNS. EXPERIMENTAL APPROACH: Analgesic effects of intravenous recombinant Cbln1 was assessed in complete Freund's adjuvant inflammatory pain model in mice. GluD1 knockout and a mutant form of Cbln1 were used. KEY RESULTS: A single intravenous injection of Cbln1 mitigated nocifensive and averse behaviour in both inflammatory and neuropathic pain models. This effect of Cbln1 was dependent on GluD1 receptors and required binding to the amino terminal domain of GluD1. Time course of analgesic effect was similar to previously reported ICV and intra-CeA injection. GluD1 in both spinal cord and CeA was down -regulated in the inflammatory pain model, whereas GluD1 expression in spinal cord but not in CeA, was partly normalized by intravenous Cbln1. Importantly, recombinant Cbln1 was detected in the synaptoneurosomes in spinal cord but not in the CeA. CONCLUSIONS AND IMPLICATIONS: Our results describe a novel mechanism by which systemic Cbln1 induces analgesia potentially by central actions involving normalization of signalling by spinal cord GluD1 receptors.


Assuntos
Dor Crônica , Proteínas do Tecido Nervoso , Neuralgia , Camundongos , Animais , Dor Crônica/tratamento farmacológico , Ácido Glutâmico , Receptores de Glutamato , Neuralgia/tratamento farmacológico , Analgésicos/uso terapêutico
7.
PLoS One ; 18(11): e0294583, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37983226

RESUMO

In this study, we investigated the role of glutamate delta 1 receptor (GluD1) in oligodendrocyte progenitor cell (OPC)-mediated myelination during basal (development) and pathophysiological (cuprizone-induced demyelination) conditions. Initially, we sought to determine the expression pattern of GluD1 in OPCs and found a significant colocalization of GluD1 puncta with neuron-glial antigen 2 (NG2, OPC marker) in the motor cortex and dorsal striatum. Importantly, we found that the ablation of GluD1 led to an increase in the number of myelin-associated glycoprotein (MAG+) cells in the corpus callosum and motor cortex at P40 without affecting the number of NG2+ OPCs, suggesting that GluD1 loss selectively facilitates OPC differentiation rather than proliferation. Further, deletion of GluD1 enhanced myelination in the corpus callosum and motor cortex, as indicated by increased myelin basic protein (MBP) staining at P40, suggesting that GluD1 may play an essential role in the developmental regulation of myelination during the critical window period. In contrast, in cuprizone-induced demyelination, we observed reduced MBP staining in the corpus callosum of GluD1 KO mice. Furthermore, cuprizone-fed GluD1 KO mice showed more robust motor deficits. Collectively, our results demonstrate that GluD1 plays a critical role in OPC regulation and myelination in normal and demyelinating conditions.


Assuntos
Doenças Desmielinizantes , Células Precursoras de Oligodendrócitos , Camundongos , Animais , Bainha de Mielina/metabolismo , Células Precursoras de Oligodendrócitos/metabolismo , Cuprizona , Ácido Glutâmico/metabolismo , Camundongos Knockout , Oligodendroglia/metabolismo , Diferenciação Celular/fisiologia , Corpo Caloso/metabolismo , Receptores de Glutamato/metabolismo , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/metabolismo , Camundongos Endogâmicos C57BL
8.
STAR Protoc ; 4(3): 102440, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37561634

RESUMO

Polypharmacology aids in the identification of multiple protein targets involved in disease pathology and selecting appropriate therapeutic compounds interacting with protein targets. Here, we present a protocol to identify the targets involved in obesity-linked diabetes and suitable phytocompounds to bind with the identified target. We describe steps to install and use softwares for identifying several protein targets by linking multiple diseases. This protocol allows the use of therapeutic compounds of both phytochemical and synthetic origins. For complete details on the use and execution of this protocol, please refer to Martiz et al.,1 and Maradesha et al.2.


Assuntos
Hidrolases , Polifarmacologia , Software
9.
Biol Psychiatry ; 94(4): 297-309, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37004850

RESUMO

BACKGROUND: Parvalbumin interneuron (PVI) activity synchronizes the medial prefrontal cortex circuit for normal cognitive function, and its impairment may contribute to schizophrenia (SZ). NMDA receptors in PVIs participate in these activities and form the basis for the NMDA receptor hypofunction hypothesis of SZ. However, the role of the GluN2D subunit, which is enriched in PVIs, in regulating molecular networks relevant to SZ is unknown. METHODS: Using electrophysiology and a mouse model with conditional deletion of GluN2D from PVIs (PV-GluN2D knockout [KO]), we examined the cell excitability and neurotransmission in the medial prefrontal cortex. Histochemical, RNA sequencing analysis and immunoblotting were conducted to understand molecular mechanisms. Behavioral analysis was conducted to test cognitive function. RESULTS: PVIs in the medial prefrontal cortex were found to express putative GluN1/2B/2D receptors. In a PV-GluN2D KO model, PVIs were hypoexcitable, whereas pyramidal neurons were hyperexcitable. Excitatory neurotransmission was higher in both cell types in PV-GluN2D KO, whereas inhibitory neurotransmission showed contrasting changes, which could be explained by reduced somatostatin interneuron projections and increased PVI projections. Genes associated with GABA (gamma-aminobutyric acid) synthesis, vesicular release, and uptake as well as those involved in formation of inhibitory synapses, specifically GluD1-Cbln4 and Nlgn2, and regulation of dopamine terminals were downregulated in PV-GluN2D KO. SZ susceptibility genes including Disc1, Nrg1, and ErbB4 and their downstream targets were also downregulated. Behaviorally, PV-GluN2D KO mice showed hyperactivity and anxiety behavior and deficits in short-term memory and cognitive flexibility. CONCLUSIONS: These findings demonstrate that GluN2D in PVIs serves as a point of convergence of pathways involved in the regulation of GABAergic synapses relevant to SZ.


Assuntos
Parvalbuminas , Esquizofrenia , Animais , Camundongos , Interneurônios/fisiologia , Camundongos Knockout , Proteínas do Tecido Nervoso/metabolismo , Parvalbuminas/metabolismo , Córtex Pré-Frontal/metabolismo , Receptor ErbB-4/metabolismo , Esquizofrenia/genética , Esquizofrenia/metabolismo
10.
Neurobiol Dis ; 181: 106117, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37031803

RESUMO

Thalamic regulation of cortical function is important for several behavioral aspects including attention and sensorimotor control. This region has also been studied for its involvement in seizure activity. Among the NMDA receptor subunits GluN2C and GluN2D are particularly enriched in several thalamic nuclei including nucleus reticularis of the thalamus (nRT). We have previously found that GluN2C deletion does not have a strong influence on the basal excitability and burst firing characteristics of reticular thalamus neurons. Here we find that GluN2D ablation leads to reduced depolarization-induced spike frequency and reduced hyperpolarization-induced rebound burst firing in nRT neurons. Furthermore, reduced inhibitory neurotransmission was observed in the ventrobasal thalamus (VB). A model with preferential downregulation of GluN2D from parvalbumin (PV)-positive neurons was generated. Conditional deletion of GluN2D from PV neurons led to a decrease in excitability and burst firing. In addition, reduced excitability and burst firing was observed in the VB neurons together with reduced inhibitory neurotransmission. Finally, young mice with GluN2D downregulation in PV neurons showed significant resistance to pentylenetetrazol-induced seizure and differences in sensitivity to isoflurane anesthesia but were normal in other behaviors. Conditional deletion of GluN2D from PV neurons also affected expression of other GluN2 subunits and GABA receptor in the nRT. Together, these results identify a unique role of GluN2D-containing receptors in the regulation of thalamic circuitry and seizure susceptibility which is relevant to mutations in GRIN2D gene found to be associated with pediatric epilepsy.


Assuntos
Receptores de N-Metil-D-Aspartato , Tálamo , Animais , Camundongos , Neurônios/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Convulsões/metabolismo , Transmissão Sináptica , Núcleos Talâmicos/metabolismo , Tálamo/metabolismo
11.
Chempluschem ; 88(3): e202200420, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36795938

RESUMO

Bimetallic metal organic frameworks (BMOFs) are a class of crystalline solids and their structure comprises two metal ions in the lattice. BMOFs show a synergistic effect of two metal centres and enhanced properties compared to MOFs. By controlling the composition and relative distribution of two metal ions in the lattice the structure, morphology, and topology of BMOFs could be regulated resulting in an improvement in the tunability of pore structure, activity, and selectivity. Thus, developing BMOFs and BMOF incorporated membranes for applications such as adsorption, separation, catalysis, and sensing is a promising strategy to mitigate environmental pollution and address the looming energy crisis. Herein we present an overview of recent advancements in the area of BMOFs and a comprehensive review of BMOF incorporated membranes reported to date. The scope, challenges as well as future perspectives for BMOFs and BMOF incorporated membranes are presented.

12.
J Biomol Struct Dyn ; 41(22): 13078-13097, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36695109

RESUMO

Phytochemical-based drug discovery against the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been the focus of the current scenario. In this context, we aimed to perform the phytochemical profiling of Magnolia champaka, an evergreen tree from the Magnoliaceae family, in order to perform a virtual screening of its phytoconstituents against different biological targets of SARS-CoV-2. The phytochemicals identified from the ethanol extract of M. champaka leaves using liquid chromatography-mass spectroscopy (LC-MS) technique were screened against SARS-CoV-2 spike glycoprotein (PDB ID: 6M0J), main protease/Mpro (PDB ID: 6LU7), and papain-like protease/PLpro (PDB ID: 7CMD) through computational tools. The experimentation design included molecular docking simulation, molecular dynamics simulation, and binding free energy calculations. Through molecular docking simulation, we identified poncirin as a common potential inhibitor of all the above-mentioned target proteins. In addition, molecular dynamics simulations, binding free energy calculations, and PCA analysis also supported the outcomes of the virtual screening. By the virtue of all the in silico results obtained, poncirin could be taken for in vitro and in vivo studies in near future.Communicated by Ramaswamy H. Sarma.


Assuntos
COVID-19 , Magnolia , SARS-CoV-2 , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Papaína , Peptídeo Hidrolases , Compostos Fitoquímicos/farmacologia , Inibidores de Proteases
13.
PLoS One ; 18(1): e0280847, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36716329

RESUMO

The current study investigates the effectiveness of phytocompounds from the whole green jackfruit flour methanol extract (JME) against obesity-linked diabetes mellitus using integrated network pharmacology and molecular modeling approach. Through network pharmacology, druglikeness and pharmacokinetics, molecular docking simulations, GO analysis, molecular dynamics simulations, and binding free energy analyses, it aims to look into the mechanism of the JME phytocompounds in the amelioration of obesity-linked diabetes mellitus. There are 15 predicted genes corresponding to the 11 oral bioactive compounds of JME. The most important of these 15 genes was MAPK3. According to the network analysis, the insulin signaling pathway has been predicted to have the strongest affinity to MAPK3 protein, which was chosen as the target. With regard to the molecular docking simulation, the greatest notable binding affinity for MAPK3 was discovered to be caffeic acid (-8.0 kJ/mol), deoxysappanone B 7,3'-dimethyl ether acetate (DBDEA) (-8.2 kJ/mol), and syringic acid (-8.5 kJ/mol). All the compounds were found to be stable inside the inhibitor binding pocket of the enzyme during molecular dynamics simulation. During binding free energy calculation, all the compounds chiefly used Van der Waal's free energy to bind with the target protein (caffeic acid: 102.296 kJ/mol, DBDEA: -104.268 kJ/mol, syringic acid: -100.171 kJ/mol). Based on these findings, it may be inferred that the reported JME phytocompounds could be used for in vitro and in vivo research, with the goal of targeting MAPK3 inhibition for the treatment of obesity-linked diabetes mellitus.


Assuntos
Artocarpus , Diabetes Mellitus , Farinha , Metanol , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Farmacologia em Rede , Obesidade/tratamento farmacológico , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia
14.
J Biomol Struct Dyn ; 41(20): 10869-10884, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36576118

RESUMO

The spike (S) glycoprotein and nucleocapsid (N) proteins are the crucial pathogenic proteins of the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS CoV-2) virus during its interaction with the host. Even FDA-approved drugs like dexamethasone and grazoprevir are not able to curb the viral progression inside the host and are reported with adverse effects on body metabolism. In this context, we aim to report corilagin a novel, potential dual inhibitor of S and N proteins from Terminalia chebula. The bioactive compounds of T. chebula were subjected to a series of computational investigations including molecular docking simulations, molecular dynamics (MD) simulations, binding free energy calculations, and PASS pharmacological analysis. The results obtained from these studies revealed that corilagin was highly interactive with the S (-8.9 kcal/mol) and N (-9.2 kcal/mol) proteins, thereby showing dual inhibition activity. It was also found to be stable enough to induce biological activity inside the inhibitor binding pocket of the target enzymes throughout the dynamics simulation run for 100 ns. This is also confirmed by the changes in the protein conformations, evaluated using free energy landscapes. Outcomes from this investigation identify corilagin as the lead potential dual inhibitor of S and N proteins of SARS-CoV-2, which could be taken for biological studies in near future.Communicated by Ramaswamy H. Sarma.


Assuntos
COVID-19 , Terminalia , SARS-CoV-2 , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteases
15.
Mycology ; 13(4): 243-256, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36405338

RESUMO

Plant-based secondary metabolite production system is well established. However, host-endophyte interaction in the production of secondary metabolite is a new less exploited area that is overcoming barriers and evolving as one of the prospective fields. Endophytes such as bacteria or fungi have the ability to produce some of the secondary metabolites that mimic the plant metabolites therefore escaping the host defence system. Coumarin is one such metabolite with immense biological functions. Most of the studies have demonstrated coumarin production from fungal endophytes but not bacterial endophytes. Herein, we present an overview of all the coumarin derivatives produced from endophytic sources and their biosynthetic pathways. Furthermore, the review also throws light on the isolation of these coumarins and different derivatives with respect to their biological activity. The biotransformation of coumarin derivatives by the action of endophytic fungi is also elaborated. The present review provides an insight on the challenges faced in the coumarin production through fungal endophytes.

16.
Molecules ; 27(19)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36234759

RESUMO

In the present study, the anti-diabetic potential of Ocimum tenuiflorum was investigated using computational techniques for α-glucosidase, α-amylase, aldose reductase, and glycation at multiple stages. It aimed to elucidate the mechanism by which phytocompounds of O. tenuiflorum treat diabetes mellitus using concepts of druglikeness and pharmacokinetics, molecular docking simulations, molecular dynamics simulations, and binding free energy studies. Isoeugenol is a phenylpropene, propenyl-substituted guaiacol found in the essential oils of plants. During molecular docking modelling, isoeugenol was found to inhibit all the target enzymes, with a higher binding efficiency than standard drugs. Furthermore, molecular dynamic experiments revealed that isoeugenol was more stable in the binding pockets than the standard drugs used. Since our aim was to discover a single lead molecule with a higher binding efficiency and stability, isoeugenol was selected. In this context, our study stands in contrast to other computational studies that report on more than one compound, making it difficult to offer further analyses. To summarize, we recommend isoeugenol as a potential widely employed lead inhibitor of α-glucosidase, α-amylase, aldose reductase, and glycation based on the results of our in silico studies, therefore revealing a novel phytocompound for the effective treatment of hyperglycemia and diabetes mellitus.


Assuntos
Diabetes Mellitus , Óleos Voláteis , Aldeído Redutase , Eugenol/análogos & derivados , Guaiacol , Simulação de Acoplamento Molecular , Ocimum sanctum , alfa-Amilases , alfa-Glucosidases
17.
Pharm Biol ; 60(1): 1656-1668, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36052952

RESUMO

CONTEXT: Michelia champaca L. (Magnoliaceae) has been known since ancient times for its rich medicinal properties. OBJECTIVE: The ethanol extract of Michelia champaca leaves (EEMC) was evaluated on depression and anxiety using in vivo and in silico studies. MATERIALS AND METHODS: Swiss albino mice were divided into control, standard, 100 and 200 mg/kg b.w. EEMC groups and for drug administration using oral gavage. The antidepressant activity was evaluated using forced swim test (FST) and tail suspension test (TST) whereas the anxiolytic activity through elevated plus maze and light and dark tests. The in silico studies included molecular docking against human potassium channel KCSA-FAB and human serotonin transporter, and ADME/T analysis. RESULTS: Open arm duration and entries were comparable between 200 mg/kg b.w. group (184.45 ± 1.00 s and 6.25 ± 1.11, respectively) and that of diazepam treated group (180.02 s ± 0.40 and 6.10 ± 0.05, respectively). Time spent in the light cubicle was higher (46.86 ± 0.03%), similar to that of diazepam (44.33 ± 0.64%), suggesting its potent anxiolytic activity. A delayed onset of immobility and lowered immobility time was seen at both the treatment doses (FST: 93.7 ± 1.70 and 89.1 ± 0.40 s; TST: 35.05 ± 2.75 and 38.50 ± 4.10 s) and the standard drug imipramine (FST: 72.7 ± 3.72 and TST: 30.01 ± 2.99 s), indicative of its antidepressant ability. In silico studies predicted doripenem to induce anxiolytic and antidepressant activity by inhibiting human potassium channel KCSA-FAB and human serotonin transporter proteins, respectively. CONCLUSIONS: EEMC is a rich source of bioactive compounds with strong antidepressant and anxiolytic properties.


Assuntos
Ansiolíticos , Magnoliaceae , Animais , Ansiolíticos/farmacologia , Ansiolíticos/uso terapêutico , Antidepressivos/farmacologia , Depressão/tratamento farmacológico , Diazepam , Humanos , Camundongos , Simulação de Acoplamento Molecular , Compostos Fitoquímicos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Canais de Potássio , Proteínas da Membrana Plasmática de Transporte de Serotonina
18.
Mar Drugs ; 20(9)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36135748

RESUMO

N-methyl-D-aspartate (NMDA) receptors play a critical role in activity-dependent dendritic arborization, spinogenesis, and synapse formation by stimulating calcium-dependent signaling pathways. Previously, we have shown that brevetoxin 2 (PbTx-2), a voltage-gated sodium channel (VGSC) activator, produces a concentration-dependent increase in intracellular sodium [Na+]I and increases NMDA receptor (NMDAR) open probabilities and NMDA-induced calcium (Ca2+) influxes. The objective of this study is to elucidate the downstream signaling mechanisms by which the sodium channel activator PbTx-2 influences neuronal morphology in murine cerebrocortical neurons. PbTx-2 and NMDA triggered distinct Ca2+-influx pathways, both of which involved the NMDA receptor 2B (GluN2B). PbTx-2-induced neurite outgrowth in day in vitro 1 (DIV-1) neurons required the small Rho GTPase Rac1 and was inhibited by both a PAK1 inhibitor and a PAK1 siRNA. PbTx-2 exposure increased the phosphorylation of PAK1 at Thr-212. At DIV-5, PbTx-2 induced increases in dendritic protrusion density, p-cofilin levels, and F-actin throughout the dendritic arbor and soma. Moreover, PbTx-2 increased miniature excitatory post-synaptic currents (mEPSCs). These data suggest that the stimulation of neurite outgrowth, spinogenesis, and synapse formation produced by PbTx-2 are mediated by GluN2B and PAK1 signaling.


Assuntos
Neurônios , Receptores de N-Metil-D-Aspartato , Quinases Ativadas por p21 , Fatores de Despolimerização de Actina/metabolismo , Actinas/metabolismo , Animais , Cálcio/metabolismo , Toxinas Marinhas , Camundongos , N-Metilaspartato , Crescimento Neuronal , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Oxocinas , RNA Interferente Pequeno/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sódio/metabolismo , Agonistas de Canais de Sódio/metabolismo , Canais de Sódio Disparados por Voltagem/metabolismo , Quinases Ativadas por p21/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo
19.
RSC Adv ; 12(37): 24192-24207, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36128541

RESUMO

A highly stereoselective, three-component method has been developed to synthesize pyrrolidine and pyrrolizidine containing spirooxindole derivatives. The interaction between the dipolarophile α,ß-unsaturated carbonyl compounds and the dipole azomethine ylide formed in situ by the reaction of 1,2-dicarbonyl compounds and secondary amino acids is referred to as the 1,3-dipolar cycloaddition reaction. The reaction conditions were optimized to achieve excellent stereo- and regioselectivity. Shorter reaction time, simple work-up and excellent yields are the salient features of the present approach. Various spectroscopic methods and single crystal X-ray diffraction examinations of one example of compound 6i validated the stereochemistry of the expected products. The anti-diabetic activity of the newly synthesized spirooxindole derivatives was tested against the α-glucosidase and α-amylase enzymes. Compound 6i was found to exhibit potent inhibition activity against α-glucosidase and α-amylase enzymes which is further evidenced by molecular docking studies.

20.
Molecules ; 27(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36014373

RESUMO

Diabetes mellitus is a major global health concern in the current scenario which is chiefly characterized by the rise in blood sugar levels or hyperglycemia. In the context, DPP4 enzyme plays a critical role in glucose homeostasis. DPP4 targets and inactivates incretin hormones such as glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP) as physiological substrates, which are essential to regulate the amount of insulin that is secreted after eating. Since the inactivation of incretins occurs, the hyperglycemic conditions continue to rise, and result in adverse physiological conditions linked with diabetes mellitus. Hence, inhibition of DPP4 has been the center of focus in the present antidiabetic studies. Although few DPP4 inhibitor drugs, such as alogliptin, saxagliptin, linagliptin, and sitagliptin, are available, their adverse effects on human metabolism are undeniable. Therefore, it becomes essential for the phytochemical intervention of the disease using computational methods prior to performing in vitro and in vivo studies. In this regard, we used an in-silico approach involving molecular docking, molecular dynamics simulations, and binding free energy calculations to investigate the inhibitory potential of Ocimum tenuiflorum phytocompounds against DPP4. In this regard, three phytocompounds (1S-α-pinene, ß-pinene, and dehydro-p-cymene) from O. tenuiflorum have been discovered as the potential inhibitors of the DPP4 protein. To summarize, from our in-silico experiment outcomes, we propose dehydro-p-cymene as the potential lead inhibitor of DPP4 protein, thereby discovering new a phytocompound for the effective management of hyperglycemia and diabetes mellitus. The reported compound can be taken for in vitro and in vivo analyses in near future.


Assuntos
Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Inibidores da Dipeptidil Peptidase IV , Hiperglicemia , Computadores , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/farmacologia , Polipeptídeo Inibidor Gástrico/metabolismo , Humanos , Hipoglicemiantes/farmacologia , Incretinas , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ocimum sanctum/metabolismo
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