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1.
J Biomol Struct Dyn ; 40(17): 8004-8017, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-33769188

RESUMO

The incurable Type 2 diabetes mellitus (T2DM) has now been considered a pandemic with only supportive care in existence. Due to the adverse effects of available anti-diabetic drugs, there arises a great urgency to develop new drug molecules. One of the alternatives that can be considered for the treatment of T2DM are natural compounds from traditionally used herbal medicine. The present study undertakes, an integrated multidisciplinary concept of Network Pharmacology to evaluate the efficacy of potent anti-diabetic compound from traditionally used anti-diabetic plants of north east India and followed by DFT analysis. In the course of the study, 22 plant species were selected on the basis of their use in traditional medicine for the treatment of T2DM by various ethnic groups of the north eastern region of India. Initially, a library of 1053 compounds derived from these plants was generated. This was followed by network preparation between compounds and targets based on the docking result. The compounds having the best network property were considered for DFT analysis. We have identified that auraptene, a monoterpene coumarin for its activity in the management of Type 2 diabetes mellitus and deciphered its unexplored probable mechanisms. Molecular dynamics simulation of the ligand-protein complexes also reveals the stable binding of auraptene with the target proteins namely, Protein Kinase C θ, Glucocorticoid receptor, 11-ß hydroxysteroid dehydrogenase 1 and Aldose Reductase, all of which form uniform interactions throughout the MD simulation trajectory. Therefore, this finding could provide new insights for the development of a new anti-diabetic drug.Communicated by Ramaswamy H. Sarma.


Assuntos
Diabetes Mellitus Tipo 2 , Medicamentos de Ervas Chinesas , Aldeído Redutase , Cumarínicos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/uso terapêutico , Ensaios de Triagem em Larga Escala , Humanos , Hidroxiesteroide Desidrogenases , Ligantes , Simulação de Acoplamento Molecular , Monoterpenos , Farmacologia em Rede , Proteína Quinase C-theta , Receptores de Glucocorticoides
2.
J Biomol Struct Dyn ; 39(10): 3802-3811, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32406317

RESUMO

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) which was first reported in Wuhan province of China, has become a deadly pandemic causing alarmingly high morbidity and mortality. In the absence of new targeted drugs and vaccines against SARS-CoV-2 at present, the choices for effective treatments are limited. Therefore, considering the exigency of the situation, we focused on identifying the available approved drugs as potential inhibitor against the promising Coronavirus drug target, the Main Protease, using computer-aided methods. We created a library of U. S. Food and Drug Administration approved anti-microbial drugs and virtually screened it against the available crystal structures of Main Protease of the virus. The study revealed that Viomycin showed the highest -CDocker energy after docking at the active site of SARS-CoV-2 Main Protease. It is noteworthy that Viomycin showed higher -CDocker energy as compared to the drugs currently under clinical trial for SARS-CoV-2 treatment viz. Ritonavir and Lopinavir. Additionally, Viomycin formed higher number of H-bonds with SARS-CoV-2 Main Protease than its co-crystallised inhibitor compound N3. Molecular dynamics simulation further showed that Viomycin embedded deeply inside the binding pocket and formed robust binding with SARS-CoV-2 Main Protease. Therefore, we propose that Viomycin may act as a potential inhibitor of the Main Protease of SARS-CoV-2. Further optimisations with the drug may support the much-needed rapid response to mitigate the pandemic.Communicated by Ramaswamy H. Sarma.


Assuntos
Antivirais , Proteases 3C de Coronavírus/antagonistas & inibidores , Inibidores de Proteases , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , Reposicionamento de Medicamentos , Simulação de Acoplamento Molecular , Inibidores de Proteases/farmacologia , Viomicina/farmacologia
3.
Biochimie ; 151: 139-149, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29883748

RESUMO

The transformation of macrophages into lipid-loaded foam cells is a critical and early event in the pathogenesis of atherosclerosis. Several recent reports highlighted that induction of TLR4 signaling promotes macrophage foam cell formation; however, the underlying molecular mechanisms have not been clearly elucidated. Here, we found that the TLR4 mediated inflammatory signaling communicated with mTORC2-Akt-mTORC1 metabolic cascade in macrophage and thereby promoting lipid uptake and foam cell formation. Mechanistically, LPS treatment markedly upregulates TLR4 mediated inflammatory pathway which by activating mTORC2 induces Akt phosphorylation at serine 473 and that aggravate mTORC1 dependent scavenger receptors expression and consequent lipid accumulation in THP-1 macrophages. Inhibition of mTORC2 either by silencing Rictor expression or inhibiting its association with mTOR notably prevents LPS induced Akt activation, scavenger receptors expression, and macrophage lipid accumulation. Although suppression of mTORC1 expression by genetic knockdown of Raptor did not produce any significant change in Akt S473 phosphorylation, however, incubation with Akt activator in Rictor silenced cells failed to promote scavenger receptors expression and macrophage foam cell formation. Thus, present research explored the signaling pathway involved in inflammation-induced macrophage foam cells formation and therefore, targeting this pathway might be useful for preventing macrophage foam cell formation.


Assuntos
Células Espumosas/metabolismo , Inflamação/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Humanos , Alvo Mecanístico do Complexo 2 de Rapamicina/química , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Células THP-1 , Receptor 4 Toll-Like/metabolismo
4.
Bioorg Med Chem Lett ; 27(16): 3698-3703, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28712709

RESUMO

A library of seventeen novel 1,2,3-triazole derivatives were efficiently synthesized in excellent yields by the popular 'click chemistry' approach and evaluated in vitro for their anti-tubercular activity against Mycobacterium tuberculosis H37Ra (ATCC 25177 strain). Among the series, six compounds exhibited significant activity with minimum inhibitory concentration (MIC) values ranging from 3.12 to 0.78µg/mL and along with no significant cytotoxicity against MBMDMQs (mouse bone marrow derived macrophages). Molecular docking of the target compounds into the active site of DprE1 (Decaprenylphosphoryl-ß-d-ribose-2'-epimerase) enzyme revealed noteworthy information on the plausible binding interactions.


Assuntos
Antituberculosos/síntese química , Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Triazóis/química , Triazóis/farmacologia , Oxirredutases do Álcool/antagonistas & inibidores , Oxirredutases do Álcool/metabolismo , Animais , Antituberculosos/toxicidade , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Células da Medula Óssea/citologia , Domínio Catalítico , Química Click , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/enzimologia , Relação Estrutura-Atividade , Termodinâmica , Triazóis/toxicidade
5.
Biomed Mater ; 9(2): 025006, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24495981

RESUMO

Polymeric biomaterials are in extensive use in the domain of tissue engineering and regenerative medicine. High performance hyperbranched epoxy is projected here as a potential biomaterial for tissue regeneration. Thermosetting hyperbranched epoxy nanocomposites were prepared with Homalomena aromatica rhizome oil-modified bentonite as well as organically modified montmorillonite clay. Fourier transformed infrared spectroscopy, x-ray diffraction and scanning and transmission electron microscopic techniques confirmed the strong interfacial interaction of clay layers with the epoxy matrix. The poly(amido amine)-cured thermosetting nanocomposites exhibited high mechanical properties like impact resistance (>100 cm), scratch hardness (>10 kg), tensile strength (48-58 MPa) and elongation at break (11.9-16.6%). Cytocompatibility of the thermosets was found to be excellent as evident by MTT and red blood cell hemolytic assays. The nanocomposites exhibited antimicrobial activity against Staphylococcus aureus (ATCC 11632), Escherichia coli (ATCC 10536), Mycobacterium smegmatis (ATCC14468) and Candida albicans (ATCC 10231) strains. In vivo biocompatibility of the best performing nanocomposite was ascertained by histopathological study of the brain, heart, liver and skin after subcutaneous implantation in Wistar rats. The material supported the proliferation of dermatocytes without induction of any sign of toxicity to the above organs. The adherence and proliferation of cells endorse the nanocomposite as a non-toxic biomaterial for tissue regeneration.


Assuntos
Materiais Biocompatíveis/química , Nanocompostos/química , Próteses e Implantes , Animais , Anti-Infecciosos/química , Candida albicans , Compostos de Epóxi/química , Escherichia coli , Masculino , Teste de Materiais , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Mycobacterium smegmatis , Polímeros/química , Ratos , Ratos Wistar , Regeneração , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus , Difração de Raios X
6.
Biomater Sci ; 2(2): 192-202, 2014 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-32481879

RESUMO

There has been a growing interest in the use of nanomaterials featuring potent biocompatibility and biodegradability together with the added facet of antibacterial activity, particularly against drug-resistant bacterial species. Addressing these three features at the biointerface, we report the fabrication of multimodal bio-based hyperbranched poly(ester amide) (HBPEA)-microwave functionalized multiwalled carbon nanotube (f-MWCNT) nanocomposites by incorporation of various weight percentages (1, 2.5, and 5 wt%) of the f-MWCNTs into HBPEA by using an ex situ polymerization technique. Fourier transform infrared spectroscopy confirmed the structural changes upon interaction of the f-MWCNTs with HBPEA. The formation of thermosetting nanocomposites resulted in an acceptable improvement of the desired properties including their mechanical properties (∼170%), instrumental for providing mechanical integrity in cultured cells. The nanocomposite films were found to be biocompatible substrates for the in vitro adhesion and proliferation of peripheral blood mononuclear cells (PBMC) with enhanced cell viability correlating with the increase of the f-MWCNT content. The antibacterial results, monitored by a CFU count and the protein concentration, demonstrated that the prepared nanocomposites were more toxic towards Gram positive bacteria and Mycobacterium smegmatis than the Gram negative ones. The damage of bacterial cells upon interaction with the nanocomposites was validated by UV-visible spectroscopy and a SEM study. The antibacterial and biocompatibility studies suggested that these microporous nanocomposite films (3D interconnected porous structures with pore diameters of 5-105 µm and a porosity of 39.90%) possess concurrent long-term lethal activity against the bacterial cells and biocompatibility with PBMC. Thus, the prepared nanocomposites may find potential bio-medical applications, particularly as antimicrobial dressing materials for infected burn wounds.

7.
Colloids Surf B Biointerfaces ; 102: 83-5, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23010109

RESUMO

In the present research we have defined a novel green method of silver nanoparticles synthesis using Dillenia indica fruit extract. D. indica is an edible fruit widely distributed in the foothills of Himalayas and known for its antioxidant and further predicted for cancer preventive potency. The maximum absorbance of the colloidal silver nanoparticle solution was observed at 421 nm when examined with UV-vis spectrophotometer.


Assuntos
Dilleniaceae/química , Frutas/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Prata/química
8.
Luminescence ; 27(1): 16-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21618682

RESUMO

Freshwater diatom frustules show special optical properties. In this paper we observed luminescence properties of the freshwater diatom Cyclotella meneghiniana. To confirm the morphological properties we present scanning electron microscopy (SEM) images. X-ray diffraction (XRD) studies were carried out to visualize the structural properties of the frustules, confirming that silica present in diatom frustules crystallizes in an α-quartz structure. Study of the optical properties of the silica frustules of diatoms using ultra-violet-visible (UV-vis) spectroscopy and photoluminescence spectroscopy confirmed that the diatom C. meneghiniana shows luminescence in the blue region of the electromagnetic spectrum when irradiated with UV light. This property of diatoms can be exploited to obtain many applications in day-to-day life. Also, using time-resolved photoluminescence spectroscopy (TRPL) it was confirmed that this species of diatom shows bi-exponential decay.


Assuntos
Diatomáceas/química , Luminescência , Diatomáceas/efeitos da radiação , Água Doce , Porosidade , Dióxido de Silício , Análise Espectral , Difração de Raios X
9.
Chem Biol Drug Des ; 79(4): 553-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22151277

RESUMO

In this study, antimycobacterial activity of a set of synthesized chalcone derivatives against Mycobacterium tuberculosis H37Rv was investigated by quantitative structure-activity relationship (QSAR) analysis using density functional theory (DFT) and molecular mechanics (MM+)-based descriptors in both gas and solvent phases. The best molecular descriptors identified were hardness, E(HOMO) , MR(A-4) and MR(B-4') that contributed to the antimycobacterial activity of the chalcones as independent factors. The correlation of these four descriptors with their antimycobacterial activity increases with the inclusion of solvent medium, indicating their importance in studying biological activity. QSAR models revealed that in gas phase, lower values of E(HOMO) , MR(A-4) and MR(B-4') increase the antimycobacterial activity of the chalcone molecules. However, in solvent phase, lower values of E(HOMO) and MR(B-4') and higher values of MR(A-4) increase their activity.


Assuntos
Antibióticos Antituberculose/química , Antibióticos Antituberculose/farmacologia , Chalconas/química , Chalconas/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Relação Quantitativa Estrutura-Atividade , Tuberculose/tratamento farmacológico
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