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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 315: 124264, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38603961

RESUMO

Design and eco-friendly fabrication of affordable and sustainable materials for the treatment of wastewater consisting of dyes, antibiotics, and other harmful substances has always been demanding. Untreated wastewater being released from industries imposes serious threats to our ecosystem, seeking convenient approaches to diminish this alarming issue. Here in this work, we synthesized MgO/CuO nanocomposites from a plant extract of Ammi visnaga L. and then employed these nanocomposites for the treatment of organic dye (methylene blue). We characterized the synthesized nanocomposites by dynamic light scattering (DLS), zeta potential, scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), x-ray diffraction (XRD), and X-ray photoelectron microscopy (XPS). DLS presented information about the explicit size of nanocomposites, while the surface charge was examined by zeta potential. XRD provided detailed information about the crystalline behavior and the information regarding surface morphology and size was extracted by SEM, TEM, and AFM. Moreover, the fabricated nanocomposites were used as a photocatalyst in the treatment of methylene blue. The overall catalytic reaction took an hour to complete, and the value of percentage degradation was 98 %. Substantially, a detailed account of the kinetics, rate of reaction, and mechanism is also fostered in the context. The presented study can assist scientists and researchers around the world to reproduce the results and use them to apply them on a broader scale.

2.
J Biomol Struct Dyn ; : 1-13, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38124513

RESUMO

Ebola virus (EBOV) poses a severe threat as a highly infectious pathogen, causing devastating hemorrhagic fever in both humans and animals. The EBOV virus VP35 protein plays a crucial role in viral replication and exhibits the ability to suppress the host interferon cascade, leading to immune system depletion. As a potential drug target, VP35 protein inhibition holds promise for combating EBOV. To discover new drug candidates, we employed a computer-aided drug design approach, focusing on compounds capable of inhibiting VP35 protein replication. In this connection, a pharmacophore model was generated using molecular interactions between the VP35 protein and its inhibitor. ZINC and Cambridge database were screened using validated pharmacophore model. Further the compounds were filtered based on Lipinski's rule of five and subjected to MD simulation and relative binding free energy calculation. Six compounds manifest a significant docking score and strong binding interaction towards VP35 protein. MD simulations further confirmed the remarkable stability of these six complexes. Relative binding free energy calculations also showed significant ΔG value in the range of -132.3 and -49.3 kcal/mol. This study paves the way for further optimization of these compounds as potential inhibitors of VP35, facilitating subsequent experimental in vitro studies.Communicated by Ramaswamy H. Sarma.

3.
J Biomol Struct Dyn ; : 1-19, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37965722

RESUMO

The severity of the influenza virus infection is largely determined by its ability to invade the human host receptor. This critical step is conducted by utilizing hemagglutinin (HA) due to its binding with sialic acid 2,6 (SA). Though 18 subtypes (H1-H18) of HA have been identified, the most efficient one for conducting the host entry has not yet been resolved. This study aims to assess the severity of infections for HA variants by conducting a comparative docking of H1-H18 with the human SA receptor. Eighteen viral 3D structures were retrieved, minimized, and optimized for docking with human SA. In all retrieved structures, five conserved amino acid residues were selected for docking with human SA. Special protein grids were prepared by locating these five residues in the 18 selected subtypes. Results showed that H3 and H8 exerted the highest standard precision and extra precision docking scores, and the highest binding affinities with the human SA, respectively. Phylogenetic analyses confirmed the actual positioning of the selected 3D structures and showed these docked structures belonged to their usual classes due to the extremely close distances found in each docked subtype compared with its corresponding non-docked structures. H8-SA showed slightly better RMSD and SASA values than H3-SA, while H3-SIA showed more favourable radius of gyration scores than H8-SIA in the majority of the simulation period. Due to the highest affinity of binding of H3 and H8 with the human receptor, special caution should be exercised regarding any possible outbreak mediated by these subtypes in human populations. However, it is important to acknowledge a limitation inherent to the computational approach; it may hold relative rather than absolute significance. Further research is needed to deepen our understanding of the intricate interplay between HA variants and the host receptor, taking into account the broader context of viral infection dynamics.Communicated by Ramaswamy H. Sarma.

4.
J Biomol Struct Dyn ; : 1-13, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37671847

RESUMO

Resistin is a cysteine-rich secretory hormone that induces resistance to insulin, and its elevated expression is correlated with the onset of diabetes and several related metabolic disorders. Resistin performs its inhibitory role by connecting three identical subunits through Cys22-based disulfide linkages. The necessity to inhibit the formation of resistin trimer is one of the essential means to prevent the aggravation of diabetes mellitus type 2, obesity, and atherosclerosis. This study was conducted to screen the clinically approved drugs to find the most potent one to inhibit resistin with the best pharmacokinetics and drug-likeness properties. A total of 4654 clinically approved drugs were docked against the Cys22 residue of resistin. The top ten drugs with the highest high-precision (XP) docking scores were selected. Ioversol and masoprocol showed the highest XP docking and Molecular Mechanics-Generalized Born Surface Area (MMGBSA) scores, respectively, with double hydrogen bonding with the targeted Cys22. Molecular dynamics (MD) simulations showed that the masoprocol-resistin complex exhibited lower root mean square deviation (RMSD), radius of gyration, and root mean square fluctuation (RMSF) values than those observed in the ioversol-resistin complex. Both drugs induced drastic conformational changes in resistin monomer interactions. However, ioversol did not prove satisfying drug-likeness properties, while masoprocol showed the most favourable pharmacokinetic and drug-likeness properties. This study has demonstrated that masoprocol offers a novel inhibitory effect on resistin with the highest ligand affinity, making it a promising drug for combating insulin resistance.Communicated by Ramaswamy H. Sarma.

5.
J Biomol Struct Dyn ; 41(16): 7712-7724, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36106982

RESUMO

FLT3 is considered a potential target of acute myeloid leukemia therapy. In this study, we applied a computer-aided methodology unifying molecular docking and pharmacophore screening to identify potent inhibitors against FLT3. To investigate the pharmacophore area and binding mechanism of FLT3, the reported co-crystallized Gilteritinib ligand was docked into the active site using Glide XP. Based on the docking results, we identified structure-based pharmacophore characteristics resistant to potent FLT3 inhibitors. The best hypothesis was corroborated using test and decoy sets, and the verified hypo was utilized to screen the chemical database. The hits from the pharmacophore-based screening were then screened again using a structure-based method that included molecular docking at various precisions; the selected molecules were further examined and refined using drug-like filters and ADMET analysis. Finally, two hits were picked out for molecular dynamic simulation. The results showed two hits were expected to have potent inhibitory activity and excellent ADMET characteristics, and they might be used as new leads in the development of FLT3 inhibitors.Communicated by Ramaswamy H. Sarma.

7.
Int J Mol Sci ; 23(5)2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35269611

RESUMO

Epidermal growth factor receptor (EGFR) is a validated tumor marker overexpressed in various cancers such as squamous cell carcinoma (SSC) of the head and neck and gliomas. We constructed protein-drug conjugates based on the anti-EGFR Designed Ankyrin Repeat Protein (DARPin) E01, and compared the bivalent DARPin dimer (DD1) and a DARPin-Fc (DFc) to the monomeric DARPin (DM) and the antibody derived scFv425-Fc (scFvFc) in cell culture and a mouse model. The modular conjugation system, which was successfully applied for the preparation of protein-drug and -dye conjugates, uses bio-orthogonal protein-aldehyde generation by the formylglycine-generating enzyme (FGE). The generated carbonyl moiety is addressed by a bifunctional linker with a pyrazolone for a tandem Knoevenagel reaction and an azide for strain-promoted azide-alkyne cycloaddition (SPAAC). The latter reaction with a PEGylated linker containing a dibenzocyclooctyne (DBCO) for SPAAC and monomethyl auristatin E (MMAE) as the toxin provided the stable conjugates DD1-MMAE (drug-antibody ratio, DAR = 2.0) and DFc-MMAE (DAR = 4.0) with sub-nanomolar cytotoxicity against the human squamous carcinoma derived A431 cells. In vivo imaging of Alexa Fluor 647-dye conjugates in A431-xenografted mice bearing subcutaneous tumors as the SCC model revealed unspecific binding of bivalent DARPins to the ubiquitously expressed EGFR. Tumor-targeting was verified 6 h post-injection solely for DD1 and scFvFc. The total of four administrations of 6.5 mg/kg DD1-MMAE or DFc-MMAE twice weekly did not cause any sequela in mice. MMAE conjugates showed no significant anti-tumor efficacy in vivo, but a trend towards increased necrotic areas (p = 0.2213) was observed for the DD1-MMAE (n = 5).


Assuntos
Imunoconjugados , Animais , Anticorpos , Azidas , Linhagem Celular Tumoral , Proteínas de Repetição de Anquirina Projetadas , Receptores ErbB/metabolismo , Camundongos , Oligopeptídeos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Sci Total Environ ; 807(Pt 1): 150635, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34606871

RESUMO

Accurate and timely estimates of groundwater storage changes are critical to the sustainable management of aquifers worldwide, but are hindered by the lack of in-situ groundwater measurements in most regions. Hydrologic remote sensing measurements provide a potential pathway to quantify groundwater storage changes by closing the water balance, but the degree to which remote sensing data can accurately estimate groundwater storage changes is unclear. In this study, we quantified groundwater storage changes in California's Central Valley at two spatial scales for the period 2002 through 2020 using remote sensing data and an ensemble water balance method. To evaluate performance, we compared estimates of groundwater storage changes to three independent estimates: GRACE satellite data, groundwater wells and a groundwater flow model. Results suggest evapotranspiration has the highest uncertainty among water balance components, while precipitation has the lowest. We found that remote sensing-based groundwater storage estimates correlated well with independent estimates; annual trends during droughts fall within 15% of trends calculated using wells and groundwater models within the Central Valley. Remote sensing-based estimates also reliably estimated the long-term trend, seasonality, and rate of groundwater depletion during major drought events. Additionally, our study suggests that the proposed method estimate changes in groundwater at sub-annual latencies, which is not currently possible using other methods. The findings have implications for improving the understanding of aquifer dynamics and can inform regional water managers about the status of groundwater systems during droughts.


Assuntos
Água Subterrânea , Tecnologia de Sensoriamento Remoto , Secas , Hidrologia , Água
9.
Water Resour Res ; 57(5): e2020WR028658, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34219820

RESUMO

Earth observations offer potential pathways for accurately closing the water and energy balance of watersheds, a fundamental challenge in hydrology. However, previous attempts based on purely satellite-based estimates have focused on closing the water and energy balances separately. They are hindered by the lack of estimates of key components, such as runoff. Here, we posit a novel approach based on Budyko's water and energy balance constraints. The approach is applied to quantify the degree of long-term closure at the watershed scale, as well as its associated uncertainties, using an ensemble of global satellite data sets. We find large spatial variability across aridity, elevation, and other environmental gradients. Specifically, we find a positive correlation between elevation and closure uncertainty, as derived from the Budyko approach. In mountainous watersheds the uncertainty in closure is 3.9 ± 0.7 (dimensionless). Our results show that uncertainties in terrestrial evaporation contribute twice as much as precipitation uncertainties to errors in the closure of water and energy balance. Moreover, our results highlight the need for improving satellite-based precipitation and evaporation data in humid temperate forests, where the closure error in the Budyko space is as high as 1.1 ± 0.3, compared to only 0.2 ± 0.03 in tropical forests. Comparing the results with land surface model-based data sets driven by in situ precipitation, we find that Earth observation-based data sets perform better in regions where precipitation gauges are sparse. These findings have implications for improving the understanding of global hydrology and regional water management and can guide the development of satellite remote sensing-based data sets and Earth system models.

10.
Bioconjug Chem ; 32(6): 1167-1174, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34060308

RESUMO

Multiple, site-specific protein conjugation is increasingly attractive for the generation of antibody-drug conjugates (ADCs). As it is important to control the number and position of cargoes in an ADC, position-selective generation of reactive sites in the protein of interest is required. Formylglycine (FGly) residues are generated by enzymatic conversion of cysteine residues embedded in a certain amino acid sequence motif with a formylglycine-generating enzyme (FGE). The addition of copper ions increases FGE activity leading to the conversion of cysteines within less readily accepted sequences. With this tuned enzyme activity, it is possible to address two different recognition sequences using two aerobic formylglycine-generating enzymes. We demonstrate an improved and facile strategy for the functionalization of a DARPin (designed ankyrin repeat protein) and the single-chain antibody scFv425-Fc, both directed against the epidermal growth factor receptor (EGFR). The single-chain antibody was conjugated with monomethyl auristatin E (MMAE) and carboxyfluorescein (CF) and successfully tested for receptor binding, internalization, and cytotoxicity in cell culture, respectively.


Assuntos
Enzimas/metabolismo , Glicina/análogos & derivados , Imunoconjugados/química , Imunoconjugados/metabolismo , Aerobiose , Repetição de Anquirina , Cobre/química , Fluoresceínas/química , Glicina/metabolismo , Oligopeptídeos/química
11.
Front Pharmacol ; 12: 611109, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859561

RESUMO

Background: The current study presents the novel angiotensin II receptor blocker fluorophenyl benzimidazole (FPD) as an antihypertensive agent in the SHR model of hypertension. We investigated the role of cGMP, voltage-dependent L-type calcium channels, and BKCa channels in the vasorelaxant mechanisms of FPD in the rat superior mesenteric artery. Methods: The antihypertensive effect of FPD was examined using an invasive technique measuring blood pressure in SHR animals. Using a myograph, tension measurement was completed in the superior mesenteric artery to elucidate the mechanisms of vasorelaxation involving AT1 receptors, the NO/cGMP pathway, L-type calcium channels, and BKCa channels. Ion flux (Ca2+, K+) studies were conducted in aortic smooth muscle cells. Putative targets proteins were determined by in silico docking studies. A safety evaluation of FPD was carried out using Swiss albino mice. Results: FPD significantly decreased blood pressure in SHR. It relaxed superior mesenteric arteries in a concentration-dependent manner and significantly inhibited angiotensin II-induced contraction. The relaxation response was also mediated by an increase in tissue cGMP levels, inhibition of L-type calcium channels, and the opening of BKCa channels. FPD further enhanced efflux of K+ and inhibited Bay K8644-stimulated Ca2+ influx in aortic smooth muscle cells and docked well in an in silico study with the targets. It was well tolerated in the toxicity study. Conclusion: The present study reports the antihypertensive activity of novel AT-1 receptor blocker FPD at 50 and 100 mg kg-1 with cGMP, L-type calcium channels, and BKCa channels as putative targets of vasorelaxation, and was found safe in oral toxicity.

12.
Curr Top Med Chem ; 21(10): 908-919, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33902420

RESUMO

BACKGROUND: In the present study, we have explored the utility of QSAR modelling, in silico ADMET, docking, chemical semi-synthesis, and in vitro evaluation studies for the identification of active camptothecin (CPT) derivatives against cancer-targeting human liver (HepG2) and lung (A549) cancer cell lines. METHODS: Two QSAR models were developed as screenings tools using the multiple linear regression (MLR) method followed by ADMET and docking studies. The regression coefficient (r2) and cross-validation regression coefficients (rCV2T) of the QSAR model for the HepG2 cell line was 0.95 and 0.90, respectively, and for the A549 cell line, it was 0.93 and 0.81, respectively. RESULTS: In silico studies show that CPT derivatives (CPT-1 and CPT-6) possess drug-like properties. Docking performed on DNA Topoisomerase-I showed significant binding affinity. Finally, predicted active derivatives were chemically semi synthesized, spectroscopically characterized, and evaluated in-vitro for cytotoxic/anticancer activity against HepG2 and A549 cell lines. CONCLUSION: The experimental results are consistent with the predicted results. These findings may be of immense importance in the anticancer drug development from an inexpensive and widely available natural product, camptothecin.


Assuntos
Antineoplásicos/isolamento & purificação , Produtos Biológicos/isolamento & purificação , Camptotecina/isolamento & purificação , Magnoliopsida/química , Extratos Vegetais/isolamento & purificação , Células A549 , Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Camptotecina/farmacologia , DNA Topoisomerases Tipo I/química , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Modelos Lineares , Simulação de Acoplamento Molecular/métodos , Extratos Vegetais/farmacologia , Ligação Proteica , Relação Quantitativa Estrutura-Atividade , Transdução de Sinais
13.
Sci Total Environ ; 768: 144992, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33736333

RESUMO

Depletion of groundwater is accelerated due to an increase in water demand for applications in urbanized areas, agriculture sectors, and energy extraction, and dwindling surface water during changing climate. Managed aquifer recharge (MAR) is one of the several methods that can help achieve long-term water sustainability by increasing the natural recharge of groundwater reservoirs with water from non-traditional supplies such as excess surface water, stormwater, and treated wastewater. Despite the multiple benefits of MAR, the wide-scale implementation of MAR is lacking, partly because of challenges to select the location for MAR implementation and identify the MAR type based on site conditions and needs. In this review, we provide an overview of MAR types with a basic framework to select and implement specific MAR at a site based on water availability and quality, land use, source type, soil, and aquifer properties. Our analysis of 1127 MAR projects shows that MAR has been predominantly implemented in sites with sandy clay loam soil (soil group C) and with access to river water for recharge. Spatial analysis reveals that many regions with depleting water storage have opportunities to implement MAR projects. Analyzing data from 34 studies where stormwater was used for recharge, we show that MAR can remove dissolved organic carbon, most metals, E. coli but not efficient at removing most trace organics, and enterococci. Removal efficiency depends on the type of MAR. In the end, we highlight potential challenges for implementing MAR at a site and additional benefits such as minimizing land subsidence, flood risk, augmenting low dry-season flow, and minimizing salt-water intrusion. These results could help identify locations in the water-stressed regions to implement specific MAR for water sustainability.

14.
Vaccines (Basel) ; 10(1)2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-35062715

RESUMO

This study elucidated the clinical, humoral immune response and genomic analysis of vaccine breakthrough (VBT) infections after ChAdOx1 nCoV-19/Covishield vaccine in healthcare workers (HCWs). Amongst 1858 HCWs, 1639 had received either two doses (1346) or a single dose (293) of ChAdOx1 nCoV-19 vaccine. SARS-CoV-2 IgG antibodies and neutralizing antibodies were measured in the vaccinated group and the development of SARS-CoV-2 infection was monitored.Forty-six RT-PCR positive samples from the 203 positive samples were subjected to whole genome sequencing (WGS). Of the 203 (10.92%) infected HCWs, 21.46% (47/219) were non-vaccinated, which was significantly more than 9.52% (156/1639) who were vaccinated and infection was higher in doctors and nurses. Unvaccinated HCWs had 1.57 times higher risk compared to partially vaccinated HCWs and 2.49 times higher risk than those who were fully vaccinated.The partially vaccinated were at higher risk than the fully vaccinated (RR 1.58). Antibody non-response was seen in 3.44% (4/116), low antibody levels in 15.51% (18/116) and medium levels were found in 81.03% (94/116). Fully vaccinated HCWs had a higher antibody response at day 42 than those who were partially vaccinated (8.96 + 4.00 vs. 7.17 + 3.82). Whole genome sequencing of 46 samples revealed that the Delta variant (B.1.617.2) was predominant (69.5%). HCWs who had received two doses of vaccine showed better protection from mild, moderate, or severe infection, with a higher humoral immune response than those who had received a single dose. The genomic analysis revealed the predominance of the Delta variant (B.1.617.2) in the VBT infections.

15.
Curr Top Med Chem ; 21(9): 767-776, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32484109

RESUMO

Brevifoliol is an abeo-taxane isolated from the Taxus wallichiana needles; eighteen semisynthetic esters derivatives of brevifoliol were prepared by Steglich esterification and screened for their anti-tubercular potential against Mycobacterium tuberculosis H37Ra avirulent strain. The 3- [chloro (7)] and 3, 5-[dinitro (8)] benzoic acid ester derivatives were most active (MIC 25 ug/ml) against the pathogen. Further, in silico docking studies of the active derivative 7 with mycobacterium enzyme inhA (enoyl-ACP reductase) gave the LibDock score of 152.68 and binding energy of -208.62 and formed three hydrogen bonds with SER94, MET98, and SER94. Similarly, when derivative 8 docked with inhA, it gave the LibDock score of 113.55 and binding energy of -175.46 and formed a single hydrogen bond with GLN100 and Pi-interaction with PHE97. On the other hand, the known standard drug isoniazid (INH) gave the LibDock score of 61.63, binding energy of -81.25 and formed one hydrogen bond with ASP148. These molecular docking results and the way of binding pattern indicated that compounds 7 and 8 bound well within the binding pocket of inhA and showed a higher binding affinity than the known drug isoniazid. Additionally, both the derivatives (7 and 8) showed no cytotoxicity, with CC50 195.10 and 111.36, respectively towards the mouse bone marrow-derived macrophages.


Assuntos
Antituberculosos/uso terapêutico , Taxoides/uso terapêutico , Animais , Antituberculosos/química , Antituberculosos/farmacologia , Simulação por Computador , Esterificação , Camundongos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Taxoides/química , Taxoides/farmacologia
16.
Curr Top Med Chem ; 21(8): 686-695, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33280598

RESUMO

BACKGROUND: Liver cancer is ranked as the fifth most prevalent and third most lethal cancer worldwide. The incidence rates of this cancer are on the rise, and only limited treatment options are available. METHODS: To identify and optimize the inhibitors of liver cancer cell-lines, a QSAR model was developed by using multiple linear regression methods. The robustness of the model was validated through statistical methods and wet-lab experiments. RESULTS: The developed QSAR models yielded high activity descriptor relationship accuracy of 91%, referred to by regression coefficient (r2= 0.91), and a high activity prediction accuracy of 89%. The external predicted (pred_r2) ability of the model was found to be 90%. CONCLUSION: The QSAR study indicates that chemical descriptors such as to measure of electronegative atom count (Epsilon3), atom type count descriptors (MMFF_10), number of a carbon atom connected with four single bonds (SssssCE- index), molecular weight and, number of oxygen atom connected with two aromatic bonds (SaaOE-index) are significantly correlated with anticancer activity. The model, which was validated statistically and through wet-lab experiments, was further used in the virtual screening of potential inhibitors against the liver cancer cell line WRL68. ADMET risk screening, synthetic accessibility, and Lipinski's rule of five are used to filter false positive hits. AfterwardS, to achieve a set of aligned ligand poses and rank the predicted active compounds, docking studies were carried out. The studied compounds and their metabolites were also analyzed for different pharmacokinetics parameters. Finally, a series of compounds was proposed as anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Hepáticas/patologia , Antineoplásicos/química , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Humanos , Simulação de Acoplamento Molecular , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos Testes
17.
Mol Pharm ; 17(6): 1827-1834, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32347728

RESUMO

Amyloidosis is a well-known but poorly understood phenomenon caused by the aggregation of proteins, often leading to pathological conditions. For example, the aggregation of insulin poses significant challenges during the preparation of pharmaceutical insulin formulations commonly used to treat diabetic patients. Therefore, it is essential to develop inhibitors of insulin aggregation for potential biomedical applications and for important mechanistic insights into amyloidogenic pathways. Here, we have identified a small molecule M1, which causes a dose-dependent reduction in insulin fibril formation. Biophysical analyses and docking results suggest that M1 likely binds to partially unfolded insulin intermediates. Further, M1-treated insulin had lower cytotoxicity and remained functionally active in regulating cell proliferation in cultured Drosophila wing epithelium. Thus, M1 is of great interest as a novel agent for inhibiting insulin aggregation during biopharmaceutical manufacturing.


Assuntos
Amiloide/metabolismo , Amiloidose/prevenção & controle , Insulina/metabolismo , Fármacos Neuroprotetores/farmacologia , Amiloide/ultraestrutura , Animais , Sobrevivência Celular/efeitos dos fármacos , Dicroísmo Circular , Drosophila , Eletroforese em Gel de Poliacrilamida , Células HEK293 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Transmissão
18.
Nat Prod Res ; 34(12): 1735-1742, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30580626

RESUMO

Novel Mannich base derivatives of glabridin were synthesized and their antiproliferative activity were performed along with our previously reported glabridin-chalcone hybrids molecules (GCHMs) against various human cell lines MDA-MB-231 (breast adenocarcinoma), HEK-293 (embryonic kidney cell line), K562 (leukemia), MCF-7 (breast adenocarcinoma), HeLa (cervix adenocarcinoma), HepG2 (hepatocellular carcinoma) and WRL-68 (hepatic carcinoma). The result showed that the glabridin significantly reduced cell proliferation with IC50 ranges from 3.67 to 58.30 µM against all the tested cell lines. The remarkable reduction in antiproliferative activity 2',4'-dimethoxyglabridin and GCHMs compounds with phenolic OH groups protected by methoxy (OCH3) groups suggested that the free OH groups are essential factor for the antiproliferative activity of glabridin and its derivatives. The Mannich base derivatives of glabridin showed moderate activity IC50 (2.20->95.78 µM). Furthermore, in silico target identification analysis revealed that AKT1, DECR1 and NOS1 are the potential targets for glabridin and their derivatives.


Assuntos
Antineoplásicos/farmacologia , Isoflavonas/farmacologia , Fenóis/farmacologia , Antineoplásicos/química , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Chalcona/farmacologia , Simulação por Computador , Proteínas Ligadas por GPI/antagonistas & inibidores , Humanos , Isoflavonas/síntese química , Óxido Nítrico Sintase Tipo I/antagonistas & inibidores , Fenóis/síntese química , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Membro 10c de Receptores do Fator de Necrose Tumoral/antagonistas & inibidores , Relação Estrutura-Atividade
19.
Curr Top Med Chem ; 19(14): 1191-1200, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31210109

RESUMO

BACKGROUND: Lymphatic filariasis is one of the chronic diseases in many parts of the tropics and sub-tropics of the world despite the use of standard drugs diethylcarbamazine and ivermectin because they kill microfilaries and not the adult parasites. Therefore, new leads with activity on adult parasites are highly desirable. OBJECTIVE: Anti-filarial lead optimization by semi-synthetic modification of glycyrrhetinic acid (GA). METHODS: The GA was first converted into 3-O-acyl derivative, which was further converted into 12 amide derivatives. All these derivatives were assessed for their antifilarial potential by parasite motility assay. The binding affinity of active GA derivatives on trehalose-6-phosphate phosphatase (Bm-TPP) was assessed by molecular docking studies. RESULTS: Among 15 GA derivatives, GAD-2, GAD-3, and GAD-4 were found more potent than the GA and standard drug DEC. These derivatives reduced the motility of Brugia malayi adult worms by up to 74% while the GA and DEC reduced only up to 49%. Further, GA and most of its derivatives exhibited two times more reduction in MTT assay when compared to the standard drug DEC. These derivatives also showed 100% reduction of microfilariae and good interactions with Bm-TPP protein. CONCLUSION: The present study suggests that 3-O-acyl and linear chain amide derivatives of glycyrrhetinic acid may be potent leads against B. malayi microfilariae and adult worms. These results might be helpful in developing QSAR model for optimizing a new class of antifilarial lead from a very common, inexpensive, and non toxic natural product.


Assuntos
Brugia Malayi/efeitos dos fármacos , Filaricidas/farmacologia , Ácido Glicirretínico/farmacologia , Simulação de Acoplamento Molecular , Doenças Negligenciadas/tratamento farmacológico , Animais , Filaricidas/síntese química , Filaricidas/química , Ácido Glicirretínico/síntese química , Ácido Glicirretínico/química , Humanos , Testes de Sensibilidade Parasitária , Relação Quantitativa Estrutura-Atividade
20.
Eur J Pharmacol ; 858: 172482, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31233749

RESUMO

In the present study, we report that neolignan1 (Diethyl-4,4'-dihydroxy-8,3'-neolign-7,7'-dien-9,9'-dionate) relaxes the superior mesenteric artery in a concentration dependent manner (pD2 value 5.392 ±â€¯0.04; n = 8 for endothelium intact and 5.204 ±â€¯0.03; n = 8 for endothelium denuded mesenteric rings, respectively). The relaxation response of neolignan1 was found to be endothelium independent and sensitive to 1H-[1,2,4] oxadiazolo [4,3-a]quinoxalin-1-on (ODQ; 1 µM) and tetraethyl ammonium (TEA; 1 mM). In-silico studies showed good LibDock score (92.66) of neolignan1 with BKCa channel and are in well corroboration with ex-vivo study. Further, neolignan1 significantly decreased the systolic blood pressure, diastolic blood pressure and mean arterial pressure in the Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME; 50 mg/kg) treated Wistar rats at the dose of 30 and 100 mg/kg given once orally for 15 days. In addition, neolignan1 is well tolerated up to 100 mg/kg when given as a repeated dose, once orally for 28 days in Swiss albino mice. Neolignan1 was well absorbed from oral route, reached peak at 4 h and eliminated below detection level by 12 h after administration. Our present study concludes that neolignan1 produced relaxation in superior mesenteric artery by opening of BKCa channel and produced significant antihypertensive activity in L-NAME treated Wistar rats and was well tolerated by the experimental animal.


Assuntos
Anti-Hipertensivos/farmacologia , Ácidos Cumáricos/farmacologia , Lignanas/farmacologia , NG-Nitroarginina Metil Éster/farmacologia , Animais , Anti-Hipertensivos/metabolismo , Anti-Hipertensivos/farmacocinética , Ácidos Cumáricos/metabolismo , Ácidos Cumáricos/farmacocinética , Feminino , Humanos , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/química , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Lignanas/metabolismo , Lignanas/farmacocinética , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/fisiologia , Camundongos , Simulação de Acoplamento Molecular , Conformação Proteica , Ratos , Ratos Wistar , Vasodilatação/efeitos dos fármacos
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