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1.
bioRxiv ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38712097

RESUMO

Upon antigenic stimulation, CD4 + T-cells undergo clonal expansion, elevating their bioenergetic demands and utilization of nutrients like glucose and glutamine. The nuclear factor erythroid 2-related factor 2 (Nrf2) is a well-known regulator of oxidative stress, but its involvement in modulating the metabolism of CD4 + T-cells remains unexplored. Here, we elucidate the role of Nrf2 beyond the traditional antioxidation, in modulating activation-driven expansion of CD4 + T-cells by influencing their nutrient metabolism. T-cell-specific activation of Nrf2 enhances early activation and IL-2 secretion, upregulates TCR-signaling, and increases activation-driven proliferation of CD4 + T-cells. Mechanistically, high Nrf2 inhibits glucose metabolism through glycolysis but promotes glutamine metabolism via glutaminolysis to support increased T-cell proliferation. Further, Nrf2 expression is temporally regulated in activated CD4 + T-cells with elevated expression during the early activation, but decreased expression thereafter. Overall, our findings uncover a novel role of Nrf2 as a metabolic modulator of CD4 + T-cells, thus providing a framework for improving Nrf2-targeting therapies and T-cell immunotherapies.

2.
bioRxiv ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38645056

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is a major health concern due to its high mortality from poor treatment responses and locoregional tumor invasion into life sustaining structures in the head and neck. A deeper comprehension of HNSCC invasion mechanisms holds the potential to inform targeted therapies that may enhance patient survival. We previously reported that doublecortin like kinase 1 (DCLK1) regulates invasion of HNSCC cells. Here, we tested the hypothesis that DCLK1 regulates proteins within invadopodia to facilitate HNSCC invasion. Invadopodia are specialized subcellular protrusions secreting matrix metalloproteinases that degrade the extracellular matrix (ECM). Through a comprehensive proteome analysis comparing DCLK1 control and shDCLK1 conditions, our findings reveal that DCLK1 plays a pivotal role in regulating proteins that orchestrate cytoskeletal and ECM remodeling, contributing to cell invasion. Further, we demonstrate in TCGA datasets that DCLK1 levels correlate with increasing histological grade and lymph node metastasis. We identified higher expression of DCLK1 in the leading edge of HNSCC tissue. Knockdown of DCLK1 in HNSCC reduced the number of invadopodia, cell adhesion and colony formation. Using super resolution microscopy, we demonstrate localization of DCLK1 in invadopodia and colocalization with mature invadopodia markers TKS4, TKS5, cortactin and MT1-MMP. We carried out phosphoproteomics and validated using immunofluorescence and proximity ligation assays, the interaction between DCLK1 and motor protein KIF16B. Pharmacological inhibition or knockdown of DCLK1 reduced interaction with KIF16B, secretion of MMPs, and cell invasion. This research unveils a novel function of DCLK1 within invadopodia to regulate the trafficking of matrix degrading cargo. The work highlights the impact of targeting DCLK1 to inhibit locoregional invasion, a life-threatening attribute of HNSCC.

3.
Bioinformatics ; 39(10)2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37796801

RESUMO

SUMMARY: The Tapestri platform offers DNA and protein analysis at the single-cell level. Integrating both types of data is beneficial for studying multiple cell populations in heterogeneous microenvironments, such as tumor tissues. Here, we present optima, an R package for the processing and analysis of data generated from the Tapestri platform. This package provides streamlined functionality for raw data filtering, integration, normalization, transformation, and visualization. Insights gained from the optima package help users to identify unique cell populations and uncover surface protein expression patterns. The results generated by optima help researchers elucidate dynamic changes at the single-cell level in heterogeneous microenvironments. AVAILABILITY AND IMPLEMENTATION: This package is available in Github: https://github.com/rachelgriffard/optima.


Assuntos
Multiômica , Software , Análise de Dados
4.
Biochem J ; 480(20): 1675-1691, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37815456

RESUMO

Although Microrchidia 2 (MORC2) is widely overexpressed in human malignancies and linked to cancer cell proliferation, metabolism, and metastasis, the mechanism of action of MORC2 in cancer cell migration and invasion is yet undeciphered. Here, we identified for the first time that MORC2, a chromatin remodeler, regulates E-cadherin expression and, subsequently regulates breast cancer cell migration and invasion. We observed a negative correlation between the expression levels of MORC2 and E-cadherin in breast cancer. Furthermore, the overexpression of MORC2 resulted in decreased expression levels of E-cadherin. In addition, co-immunoprecipitation and chromatin immunoprecipitation assays revealed that MORC2 interacts with HDAC1 and gets recruited onto the E-cadherin promoter to inhibit its transcription, thereby suppress its expression. Consequently, knockdown of HDAC1 in MORC2-overexpressing cells led to reduced cancer cell migration and invasion. Interestingly, we noticed that MORC2-regulated glucose metabolism via c-Myc, and LDHA, also modulates the expression of E-cadherin. Collectively, these results demonstrate for the first time a mechanistic role for MORC2 as an upstream regulator of E-cadherin expression and its associated functions in breast cancer.


Assuntos
Neoplasias da Mama , Histona Desacetilase 1 , Humanos , Feminino , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Linhagem Celular Tumoral , Caderinas/genética , Caderinas/metabolismo , Neoplasias da Mama/genética , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição/metabolismo
5.
Int J Mol Sci ; 24(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37685885

RESUMO

Ovarian follicles undergo a series of dynamic changes following the ovulatory surge of luteinizing hormone including cumulus expansion, oocyte maturation, ovulation, and luteinization. Post-transcriptional gene regulatory events are critical for mediating LH follicular responses, and among all RNA isoforms, circular RNA (circRNA) is one of the most abundant forms present in cells, yet they remain the least studied. Functionally, circRNA can act as miRNA sponges, protein sponges/decoys, and regulators of transcription and translation. In the context of ovarian follicular development, the identity and roles of circRNA are relatively unknown. In the present study, high throughput RNA sequencing of granulosa cells immediately prior to and 4-h after the LH/hCG surge identified 42,381 circRNA originating from 7712 genes. A total of 54 circRNA were identified as differentially expressed between 0-h and 4-h time points (Fold Change ± 1.5, FDR ≤ 0.1), among them 42 circRNA were upregulated and 12 circRNA were downregulated. All differentially expressed circRNA between the 0-h and 4-h groups were subjected to circinteractome analysis and identified networks of circRNA-protein and circRNA-miRNA were further subjected to "micro-RNA target filter analysis" in Ingenuity Pathway Analyses, which resulted in the identification of miRNA targeted mRNAs. A comparison of these circRNA target mRNAs with LH-induced mRNAs identified Runx2, Egfr, Areg, Sult1el, Cyp19a1, Cyp11a1, and Hsd17b1 as targets of circKif2, circVcan, circMast4, and circMIIt10. These newly identified LH/hCG-induced circRNA, their target miRNA and protein networks provide new insights into the complex interactions associated with periovulatory follicular development.


Assuntos
Células da Granulosa , RNA Circular , Feminino , Animais , Camundongos , RNA Circular/genética , Folículo Ovariano , Enzima de Clivagem da Cadeia Lateral do Colesterol , Citocromo P-450 CYP1A1
6.
J Clin Invest ; 133(11)2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37071471

RESUMO

Characterized by the accumulation of somatic mutations in blood cell lineages, clonal hematopoiesis of indeterminate potential (CHIP) is frequent in aging and involves the expansion of mutated hematopoietic stem and progenitor cells (HSC/Ps) that leads to an increased risk of hematologic malignancy. However, the risk factors that contribute to CHIP-associated clonal hematopoiesis (CH) are poorly understood. Obesity induces a proinflammatory state and fatty bone marrow (FBM), which may influence CHIP-associated pathologies. We analyzed exome sequencing and clinical data for 47,466 individuals with validated CHIP in the UK Biobank. CHIP was present in 5.8% of the study population and was associated with a significant increase in the waist-to-hip ratio (WHR). Mouse models of obesity and CHIP driven by heterozygosity of Tet2, Dnmt3a, Asxl1, and Jak2 resulted in exacerbated expansion of mutant HSC/Ps due in part to excessive inflammation. Our results show that obesity is highly associated with CHIP and that a proinflammatory state could potentiate the progression of CHIP to more significant hematologic neoplasia. The calcium channel blockers nifedipine and SKF-96365, either alone or in combination with metformin, MCC950, or anakinra (IL-1 receptor antagonist), suppressed the growth of mutant CHIP cells and partially restored normal hematopoiesis. Targeting CHIP-mutant cells with these drugs could be a potential therapeutic approach to treat CH and its associated abnormalities in individuals with obesity.


Assuntos
Hematopoiese Clonal , Neoplasias Hematológicas , Animais , Camundongos , Humanos , Hematopoiese Clonal/genética , Hematopoese/genética , Células-Tronco Hematopoéticas/patologia , Inflamação/genética , Inflamação/patologia , Neoplasias Hematológicas/genética , Obesidade/complicações , Obesidade/genética , Obesidade/patologia , Mutação
7.
Med Oncol ; 40(3): 102, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36802305

RESUMO

Cancer cell proliferation is a high energy demanding process, where the cancer cells acquire energy by high rates of glycolysis, and this phenomenon is known as the "Warburg effect". Microrchidia 2 (MORC2), an emerging chromatin remodeler, is over expressed in several cancers including breast cancer and found to promote cancer cell proliferation. However, the role of MORC2 in glucose metabolism in cancer cells remains unexplored. In this study, we report that MORC2 interacts indirectly with the genes involved in glucose metabolism via transcription factors MAX (MYC-associated factor X) and MYC. We also found that MORC2 co-localizes and interacts with MAX. Further, we observed a positive correlation of expression of MORC2 with glycolytic enzymes Hexokinase 1 (HK1), Lactate dehydrogenase A (LDHA) and Phosphofructokinase platelet (PFKP) type in multiple cancers. Surprisingly, the knockdown of either MORC2 or MAX not only decreased the expression of glycolytic enzymes but also inhibited breast cancer cell proliferation and migration. Together, these results demonstrate the involvement of the MORC2/MAX signaling axis in the expression of glycolytic enzymes and breast cancer cell proliferation and migration.


Assuntos
Neoplasias da Mama , Fatores de Transcrição , Feminino , Humanos , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Glucose , Glicólise , Fatores de Transcrição/genética
8.
Comput Struct Biotechnol J ; 21: 3224-3233, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38213901

RESUMO

JQ1 and GSK2801 are bromo domain inhibitors (BDI) known to exhibit enhanced anti-cancer activity when combined with other agents. However, the underlying molecular mechanisms behind such enhanced activity remain unclear. We used network-pharmacology approaches to understand the shared molecular mechanisms behind the enhanced activity of JQ1 and GSK2801 when used together to treat breast cancer (BC). The gene targets of JQ1 and GSK2801 were intersected with known BC-targets and their putative targets against BC were derived. The key genes were explored through gene-ontology-enrichment, Protein-Protein-Interaction (PPI) networking, survival analysis, and molecular modeling simulations. The genes, CTSB, MAPK14, MET, PSEN2 and STAT3, were found to be common targets for both drugs. In total, 49 biological processes, five molecular functions and 61 metabolic pathways were similarly enriched for JQ1 and GSK2801 BC targets among which several terms are related to cancer: IL-17, TNF and JAK-STAT signaling pathways. Survival analyses revealed that all five putative synergistic targets are significantly associated with survival in BC (log-rank p < 0.05). Molecular modeling studies showed stable binding of JQ1 and GSK2801 against their targets. In conclusion, this study explored and illuminated the possible molecular mechanisms behind the enhanced activity of JQ1 and GSK2801 against BC and suggests synergistic action through their similar BC-targets and gene-ontologies.

9.
BMC Cancer ; 22(1): 627, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35672711

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) constitutes 10-20% of breast cancers and is challenging to treat due to a lack of effective targeted therapies. Previous studies in TNBC cell lines showed in vitro growth inhibition when JQ1 or GSK2801 were administered alone, and enhanced activity when co-administered. Given their respective mechanisms of actions, we hypothesized the combinatorial effect could be due to the target genes affected. Hence the target genes were characterized for their expression in the TNBC cell lines to prove the combinatorial effect of JQ1 and GSK2801. METHODS: RNASeq data sets of TNBC cell lines (MDA-MB-231, HCC-1806 and SUM-159) were analyzed to identify the differentially expressed genes in single and combined treatments. The topmost downregulated genes were characterized for their downregulated expression in the TNBC cell lines treated with JQ1 and GSK2801 under different dose concentrations and combinations. The optimal lethal doses were determined by cytotoxicity assays. The inhibitory activity of the drugs was further characterized by molecular modelling studies. RESULTS: Global expression profiling of TNBC cell lines using RNASeq revealed different expression patterns when JQ1 and GSK2801 were co-administered. Functional enrichment analyses identified several metabolic pathways (i.e., systemic lupus erythematosus, PI3K-Akt, TNF, JAK-STAT, IL-17, MAPK, Rap1 and signaling pathways) enriched with upregulated and downregulated genes when combined JQ1 and GSK2801 treatment was administered. RNASeq identified downregulation of PTPRC, MUC19, RNA5-8S5, KCNB1, RMRP, KISS1 and TAGLN (validated by RT-qPCR) and upregulation of GPR146, SCARA5, HIST2H4A, CDRT4, AQP3, MSH5-SAPCD1, SENP3-EIF4A1, CTAGE4 and RNASEK-C17orf49 when cells received both drugs. In addition to differential gene regulation, molecular modelling predicted binding of JQ1 and GSK2801 with PTPRC, MUC19, KCNB1, TAGLN and KISS1 proteins, adding another mechanism by which JQ1 and GSK2801 could elicit changes in metabolism and proliferation. CONCLUSION: JQ1-GSK2801 synergistically inhibits proliferation and results in selective gene regulation. Besides suggesting that combinatorial use could be useful therapeutics for the treatment of TNBC, the findings provide a glimpse into potential mechanisms of action for this combination therapy approach.


Assuntos
Azepinas/farmacologia , Carcinoma Hepatocelular , Neoplasias Hepáticas , Triazóis/farmacologia , Neoplasias de Mama Triplo Negativas , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Proliferação de Células , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Cisteína Endopeptidases/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Humanos , Indolizinas , Kisspeptinas/genética , Neoplasias Hepáticas/genética , Fosfatidilinositol 3-Quinases/metabolismo , Receptores Depuradores Classe A/genética , Sulfonas , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo
10.
J Food Sci Technol ; 58(12): 4567-4577, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34629521

RESUMO

Hypertension is a threatening chronic disease, which become a global killer among the adult population. The mortality rate increasing day by day even several Angiotensin I-converting enzyme (ACE) inhibitor drugs were introduced. Bioactive peptides derived from aquatic resources exhibits potential ACE inhibitory activity. The objective of this work is to report the purification and molecular docking studies of angiotensin-I converting enzyme (ACE) inhibitory peptide isolated from shortfin scad (Decapterus macrosoma) waste protein hydrolysate (SWH), enzymatically prepared by using alcalase. The purification process included ultrafiltration, gel filtration and reverse phase high performance liquid chromatography (RP-HPLC). Results showed that ultra-filtered peptide fraction (< 3 kDa) possessed the highest ACE inhibitory activity, followed by the fraction 14 by gel filtration. Fraction P obtained by RP-HPLC, with the amino acid sequence of RGVGPVPAA (IC50 = 0.20 mg/ml) was identified. In terms of ACE inhibition, the Lineweaver-Burk plot showed that the SWH peptide obtained acted as a competitive ACE inhibitor. The molecular docking studies showed that the SWH peptide exhibit hydrogen bonds and Pi-interactions with ACE by Z-dock scores. These results showed that the purified peptide isolated from shortfin scad waste hydrolysate has potential antihypertensive properties which could potentially be used as functional food ingredients.

11.
Vaccines (Basel) ; 8(4)2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33050053

RESUMO

Coronavirus disease (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is one of the pressing contemporary public health challenges. Investigations into the genomic structure of SARS-CoV-2 may inform ongoing vaccine development efforts and/or provide insights into vaccine efficacy to fight against COVID-19. Evolutionary analysis of 540 genomes spanning 20 different countries/territories was conducted and revealed an increase in the genomic divergence across successive generations. The ancestor of the phylogeny was found to be the isolate from the 2019/2020 Wuhan outbreak. Its transmission was outlined across 20 countries/territories as per genomic similarity. Our results demonstrate faster evolving variations in the genomic structure of SARS-CoV-2 when compared to the isolates from early stages of the pandemic. Genomic alterations were predominantly located and mapped onto the reported vaccine candidates of structural genes, which are the main targets for vaccine candidates. S protein showed 34, N protein 25, E protein 2, and M protein 3 amino acid variations in 246 genomes among 540. Among identified mutations, 23 in S protein, 1 in E, 2 from M, and 7 from N protein were mapped with the reported vaccine candidates explaining the possible implications on universal vaccines. Hence, potential target regions for vaccines would be ideally chosen from the structural regions of the genome that lack high variation. The increasing variations in the genome of SARS-CoV-2 together with our observations in structural genes have important implications for the efficacy of a successful universal vaccine against SARS-CoV-2.

12.
Acta Trop ; 211: 105601, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32598921

RESUMO

VectorInfo is a freely accessible web resource, emphasised on medically important Indian arthropods funded by Indian Council of Medical Research (ICMR) and maintained by one of its premier institute, Vector Control Research Centre (VCRC). VectorInfo elucidates and curates medically important Indian arthropod's biological, omics technologies to adopt a holistic view of the molecules that make up an organism, aimed at the detection of genomics, transcriptomics, proteomics, enzymes & pathways and immune specific genes. The nitty-gritty of VectorInfo is aimed at scrutinizing all the possible information on Indian disease vectors in a single window for the scientific community. The database affords 53 medically important Indian arthropod's biological and omics information well-structured and provided with downloadable facilities. In addition to this, huge number of research articles were mined in the quest for gathering the recommended insecticide targets and their mechanisms, that pave ways to design and develop novel lead molecules through computational means. This current up-to-date database contains 2,498 omics entries beneficial for the molecular studies and analysis. In order to maintain regular updates, user forms were provided for the scientific community to submit research data to the database administrator. The VectorInfo furthermore conveys various resources for vector control and diagnostics and the links to the crucial software tools used for the Bioinformatics analysis.


Assuntos
Vetores Artrópodes/genética , Vetores Artrópodes/parasitologia , Bases de Dados Genéticas , Genômica , Internet , Informática Médica , Animais , Humanos , Índia
13.
Cancer Prev Res (Phila) ; 13(7): 623-634, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32312713

RESUMO

We conducted a multiinstitutional, placebo-controlled phase IIB trial of the lignan secoisolariciresinol diglucoside (SDG) found in flaxseed. Benign breast tissue was acquired by random periareolar fine needle aspiration (RPFNA) from premenopausal women at increased risk for breast cancer. Those with hyperplasia and ≥2% Ki-67 positive cells were eligible for randomization 2:1 to 50 mg SDG/day (Brevail) versus placebo for 12 months with repeat bio-specimen acquisition. The primary endpoint was difference in change in Ki-67 between randomization groups. A total of 180 women were randomized, with 152 ultimately evaluable for the primary endpoint. Median baseline Ki-67 was 4.1% with no difference between arms. Median Ki-67 change was -1.8% in the SDG arm (P = 0.001) and -1.2% for placebo (P = 0.034); with no significant difference between arms. As menstrual cycle phase affects proliferation, secondary analysis was performed for 117 women who by progesterone levels were in the same phase of the menstrual cycle at baseline and off-study tissue sampling. The significant Ki-67 decrease persisted for SDG (median = -2.2%; P = 0.002) but not placebo (median = -1.0%). qRT-PCR was performed on 77 pairs of tissue specimens. Twenty-two had significant ERα gene expression changes (<0.5 or >2.0) with 7 of 10 increases in placebo and 10 of 12 decreases for SDG (P = 0.028), and a difference between arms (P = 0.017). Adverse event incidence was similar in both groups, with no evidence that 50 mg/day SDG is harmful. Although the proliferation biomarker analysis showed no difference between the treatment group and the placebo, the trial demonstrated use of SDG is tolerable and safe.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Butileno Glicóis/uso terapêutico , Glucosídeos/uso terapêutico , Hiperplasia/tratamento farmacológico , Lignanas/uso terapêutico , Pré-Menopausa , Adulto , Neoplasias da Mama/patologia , Feminino , Linho/química , Seguimentos , Humanos , Hiperplasia/patologia , Pessoa de Meia-Idade , Projetos Piloto , Prognóstico , Fatores de Risco , Adulto Jovem
14.
ACS Omega ; 4(1): 2217-2224, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31660472

RESUMO

Insulin receptor substrate 1 (IRS1) is one of the major substrates for the IR, and their interaction mediates several downstream insulin signaling pathways. In this study, we have identified three novel mutations in the IRS1 gene of type 2 diabetic (T2D) patients, which reflected in the amino acid changes as I65S, R66S, and G86R in the phosphotyrosine binding domain of the IRS1 protein. The impact of these mutations on the structure and function of the IRS1 protein was evaluated through molecular modeling studies, and distinct conformational fluctuations were recorded. The variable binding affinities and positional displacement of these mutant models were observed in the ligand-binding cleft of IR. The mutant IRS1 models triggered conformational changes in the L1 domain of IR upon their binding. Such structural variations in IRS1 and IR structures due to mutations resulted in variable molecular interactions that could lead to altered insulin transduction, followed by insulin resistance and T2D.

15.
FEBS Open Bio ; 8(8): 1202-1208, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30087826

RESUMO

Glucokinase (GK) plays a vital role in the control of blood glucose levels and its altered activity can lead to the development of forms of diabetes. We have previously identified a mutant GK (R308K) in patients with type 2 diabetes with reduced enzyme activity. In the present study, the activation mechanism of GK from super-open to the closed state under wild-type and mutant conditions in the presence of the novel aminophosphonate derivative YNKGKA4 (an allosteric activator of GK) was characterized via a series of molecular dynamics simulations. A reliable conformational transition pathway of GK was observed from super-open to closed state during trajectory analysis. Glucose was also observed to modulate its binding orientation in the active site but with stable moments in the cavity. These observations provide insights into the complicated conformational transitions in the presence of YNKGKA4 and the molecular mechanism of GK activators for the allosteric regulation of mutant forms of GK.

16.
J Biomol Struct Dyn ; 36(8): 2058-2069, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28608751

RESUMO

Voltage gated sodium channels (VGSC) of mosquito vectors are the primary targets of dichlorodiphenyltrichloroethane (DDT) and other synthetic pyrethroids used in public health programmes. The knockdown resistant (kdr) mutations in VGSC are associated with the insecticide resistance especially in Anophelines. The present study is aimed to emphasize and demarcate the impact of three kdr-mutations such as L1014S, L1014F and L1014H on insecticide resistance. The membrane model of sodium transport domain of VGSC (STD-VGSC) was constructed using de novo approach based on domain and trans-membrane predictions. The comparative molecular modelling studies of wild type and mutant models of STD-VGSC revealed that L1014F mutant was observed to be near native to the wild type model in all the respects, but, L1014S and L1014H mutations showed drastic variations in the energy levels, root mean square fluctuations (RMSF) that resulted in conformational variations. The predicted binding sites also showed variable cavity volumes and RMSF in L1014S and L1014H mutants. Further, DDT also found be bound in near native manner to wild type in L1014F mutant and with variable orientation and affinities in L1014S and L1014H mutants. The variations and fluctuations observed in mutant structures explained that each mutation has its specific impact on the conformation of VGSC and its binding with DDT. The study provides new insights into the structure-function-correlations of mutant STD-VGSC structures and demonstrates the role and effects of kdr mutations on insecticide resistance in mosquito vectors.


Assuntos
Proteínas de Insetos/genética , Resistência a Inseticidas/genética , Mutação de Sentido Incorreto , Canais de Sódio Disparados por Voltagem/genética , Algoritmos , Animais , Anopheles/genética , Anopheles/metabolismo , Sítios de Ligação , DDT/química , DDT/metabolismo , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Simulação de Acoplamento Molecular , Estrutura Molecular , Ligação Proteica , Conformação Proteica , Termodinâmica , Canais de Sódio Disparados por Voltagem/química , Canais de Sódio Disparados por Voltagem/metabolismo
17.
Comput Biol Chem ; 68: 118-130, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28327441

RESUMO

Glucokinase (GK) is a potential therapeutic target of type 2 diabetes and GK activators (GKAs) represent a promising class of small organic molecules which enhance GK activity. Based on the configuration and conformation of the allosteric site of GK, we have designed a novel class of amino phosphonate derivatives in order to develop potent GKAs. The QSAR model developed using numerous descriptors revealed its potential with the best effective statistical values of RMSE=1.52 and r2=0.30. Moreover, application of this model on the present test set GKAs proved to be worthy to predict their activities as a better linear relationship was observed with RMSE=0.14 and r2=0.88. ADME studies and Lipinski filters encouraged them as safer therapeutics. The molecular dynamics and docking studies against the GK allosteric site revealed that all GKAs bind with best affinities and the complexes are strengthened by H-bonding, phosphonate salt bridges, hydrophobic and arene cat ionic interactions. Finally, in vitro evaluation with human liver GK revealed their potential to increase the GK activity by different folds. The results from QSAR, ADME, molecular docking and in vitro assays strongly suggested that the present molecules could be used as effective and safer therapeutics to control and manage type 2 diabetes.


Assuntos
Desenho de Fármacos , Ativadores de Enzimas/farmacologia , Glucoquinase/metabolismo , Organofosfonatos/farmacologia , Ativação Enzimática/efeitos dos fármacos , Ativadores de Enzimas/síntese química , Ativadores de Enzimas/química , Humanos , Fígado/enzimologia , Estrutura Molecular , Organofosfonatos/síntese química , Organofosfonatos/química
18.
J Biomol Struct Dyn ; 35(10): 2269-2279, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27456030

RESUMO

P21-activated kinase-1 (PAK1) is an enzyme associated with multiple metabolic networks and different types of cancers. Hence, there is a need to study the global network map of PAK1 to understand its role and regulatory mechanisms by means of its significant molecular interactive partners. This will help to explore its global biological functions in breast cancer. In view of this, we obtained the gene expression data-sets of PAK1 from The Cancer Genome Atlas-cBioportal and GeneCards databases and found that 91 PAK1-related genes are associated with breast cancer. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway investigations of 91 genes via Database for Annotation Visualization and Integrated Discovery bioinformatics resource revealed that, PAK1 being a major kinase is associated with several metabolic pathways and involved in phosphorylation, signal transduction, apoptosis, biosynthesis and majorly cancer-related cell signalling pathways. The PAK1 interaction network derived from STRING and Cytoscape revealed that the genes Signal-Transducer-and-Activator-of-Transcription-3 (STAT3), Cyclin-D1 (CCND1), Mitogen-activated protein kinase-1 (MAPK1), Ras-Homolog-Family-Member-A (RHOA) and Catenin-beta-1 have high degrees of interaction where CCND1, MAPK1 and RHOA have direct interaction with PAK1. Finally, the global expression map of PAK1 and its related genes was derived as topological frame that helped to explore and investigate PAK1 interactions. Further, the molecular modelling studies of PAK1 with its major interacting partners RHOA and STAT3 helped to explore the key interactive residues of PAK1 structure. This information can be used to develop novel therapeutic and control strategies against breast cancer.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Regulação Neoplásica da Expressão Gênica , Fator de Transcrição STAT3/química , Quinases Ativadas por p21/química , Proteína rhoA de Ligação ao GTP/química , Sítios de Ligação , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patologia , Biologia Computacional/métodos , Cristalografia por Raios X , Bases de Dados Genéticas , Feminino , Redes Reguladoras de Genes , Humanos , Ligação de Hidrogênio , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Mapeamento de Interação de Proteínas , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Quinases Ativadas por p21/genética , Quinases Ativadas por p21/metabolismo , Proteína rhoA de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/metabolismo
19.
Biochem Biophys Rep ; 8: 192-199, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28955956

RESUMO

There are enormous evidences and previous reports standpoint that the enzyme of glyoxylate pathway malate synthase G (MSG) is a potential virulence factor in several pathogenic organisms, including Brucella melitensis 16M. Where the lack of crystal structures for best candidate proteins like MSG of B. melitensis 16M creates big lacuna to understand the molecular pathogenesis of brucellosis. In the present study, we have constructed a 3-D structure of MSG of Brucella melitensis 16M in MODELLER with the help of crystal structure of Mycobacterium tuberculosis malate synthase (PDB ID: 2GQ3) as template. The stereo chemical quality of the restrained model was evaluated by SAVES server; remarkably we identified the catalytic functional core domain located at 4th cleft with conserved catalytic amino acids, start at ILE 59 to VAL 586 manifest the function of the protein. Furthermore, virtual screening and docking results reveals that best leadmolecules binds at the core domain pocket of MSG catalytic residues and these ligand leads could be the best prospective inhibitors to treat brucellosis.

20.
Daru ; 22: 76, 2014 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-25542373

RESUMO

BACKGROUND: Chronic and oral administration of benzylamine improves glucose tolerance. Picolylamine is a selective functional antagonist of the human adenosine A2B receptor. Phosphonic diamide derivatives enhance the cellular permeability and in turn their biological activities. METHODS: A series of heteroaryl phosphonicdiamide derivatives were designed as therapeutics to control and manage type2 diabetes. Initially defined Lipinski parameters encouraged them as safer drugs. Molecular docking of these compounds against Protein tyrosine phosphatase (PTP), the potential therapeutic target of type 2 diabetes, revealed their potential binding ability explaining their anti-diabetic activity in terms of PTP inhibition. Human intestinal absorption, Caco-2 cell permeability, MDCK cell permeability, BBB penetration, skin permeability and plasma protein binding abilities of the title compounds were calculated by PreADMET server. A convenient method has been developed for the synthesis of title compounds through the formation of 1-ethoxy-N,N'-bis(4-fluorobenzyl/pyridin-3-ylmethyl)phosphinediamine by the reaction of 4-fluorobenzylamine/ 3-picolylamine with ethyldichlorophosphite, subsequently reacted with heteroaryl halides using lanthanum(III) chloride as a catalyst. RESULTS: All the compounds exhibited significant in vitro anti-oxidant activity and in vivo evaluation in streptozotocin induced diabetic rat models revealed that the normal glycemic levels were observed on 12(th) day by 9a and 20(th) day by 5b, 5c, 9e and 9f. The remaining compounds also exhibited normal glycemic levels by 25(th) day. CONCLUSION: The results from molecular modeling, in vitro and in vivo studies are suggesting them as safer and effective therapeutic agents against type2 diabetes. Graphical Abstract Development of PTPs inhibitors.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Hipoglicemiantes/farmacologia , Compostos de Fósforo/farmacologia , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Animais , Antioxidantes/farmacologia , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Barreira Hematoencefálica/metabolismo , Células CACO-2 , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Tipo 2/sangue , Modelos Animais de Doenças , Cães , Desenho de Fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Humanos , Hipoglicemiantes/síntese química , Hipoglicemiantes/metabolismo , Absorção Intestinal , Células Madin Darby de Rim Canino , Masculino , Simulação de Acoplamento Molecular , Estrutura Molecular , Permeabilidade , Compostos de Fósforo/síntese química , Compostos de Fósforo/metabolismo , Ligação Proteica , Proteínas Tirosina Fosfatases/metabolismo , Ratos Wistar , Absorção Cutânea , Relação Estrutura-Atividade , Fatores de Tempo
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