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1.
ACS Chem Neurosci ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795037

RESUMO

Alzheimer's disease is a complex neurological disorder linked with multiple pathological hallmarks. The interrelation of therapeutic targets assists in the enhancement of cognitive decline through interference with overall neuronal transmission. We have synthesized and screened various chromone derivatives as potential multitarget-directed ligands for the effective treatment of Alzheimer's disease. The synthesized compounds exhibited multipotent activity against AChE, BuChE, MAO-B, and amyloid ß aggregation. Three potent compounds, i.e., VN-3, VN-14, and VN-19 were identified that displayed remarkable activities against different targets. These compounds displayed IC50 values of 80 nM, 2.52 µM, and 140 nM against the AChE enzyme, respectively, and IC50 values of 2.07 µM, 70 nM, and 450 nM against the MAO-B isoform, respectively. VN-3 displayed potent activity against self-induced Aß1-42 aggregation with inhibition of 58.3%. In the ROS inhibition studies, the most potent compounds reduced the intracellular ROS levels up to 80% in SH-SY5Y cells at 25 µM concentration. The compounds were found to be neuroprotective and noncytotoxic even at a concentration of 25 µM against SH-SY5Y cells. In silico studies showed that the compounds were nicely accommodated in the active sites of the receptors along with thermodynamically stable orientations. Compound VN-19 exhibited a balanced multitargeting profile against AChE, BuChE, MAO-B, and Aß1-42 enzymes and was further evaluated for in vivo activities on the scopolamine-induced zebrafish model. VN-19 was found to ameliorate the cognitive decline in zebrafish brains by protecting them against scopolamine-induced neurodegeneration. Thus, VN-3, VN-14, and VN-19 were identified as potent multitarget-directed ligands with a balanced activity profile against different targets and can be developed as therapeutics for AD.

2.
bioRxiv ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38328241

RESUMO

Sumoylation is a post-translational modification that can regulate different physiological functions. Increased sumoylation, specifically conjugation of SUMO2/3 (small ubiquitin like modifier 2/3), is detrimental to vascular health. However, the molecular mechanism mediating this effect is poorly understood. Here, we demonstrate that SUMO2 modifies p66Shc, which impairs endothelial function. Using multiple approaches, we show that p66Shc is a direct target of SUMO2. Mass spectrometry identified that SUMO2 modified lysine-81 in the unique collagen homology-2 domain of p66Shc. SUMO2ylation of p66Shc increased phosphorylation at serine-36, causing it to translocate to the mitochondria. Notably, sumoylation-deficient p66Shc (p66ShcK81R) was resistant to SUMO2-induced p66ShcS36 phosphorylation and mitochondrial translocation. Ingenuity pathway analysis showed that majority of effects of p66Shc SUMO2ylation were mediated via p66ShcK81. Finally, p66ShcK81R knockin mice were resistant to SUMO2-induced endothelial dysfunction. Collectively, our work uncovers a posttranslational modification of redox protein p66Shc and identifies SUMO2-p66Shc signaling as a regulator of vascular endothelial function.

3.
Cell Signal ; 113: 110953, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38084837

RESUMO

BACKGROUND: Cancer Stem Cells (CSCs) have emerged as a critical mediator in recurrence and resistance in cancers. Kindlin-isoform (1 and 2) binds with cytoplasmic ß-tail of integrin and are essential co-activators of integrin function. Given their important function in regulating cancer hallmarks such as cell proliferation, invasion, migration, and metastasis, we hypothesize that it might play a critical role in CSC growth, survival, and self-renewal of colon cancer. MATERIALS AND METHODS: Using knockdown approaches, we inhibited Kindlin-2 expression in HCT116 and HT29 colon cancer cells. Extreme limiting dilution and self-renewal assay were performed to measure the role of Kindlin in colonic CSC. Standard methods such as qRT-PCR and western blotting were carried out to understand the signaling cascade by which Kindlin regulates CSC marker expression and downstream targets. RESULTS: Our data show isoform-specific upregulation of Kindlin-2 in colonic CSCs. The silencing of Kindlin-2 reduces colonosphere formation, decreases CSC size, and self-renewal marker genes such as CD-133, CXCR-4, LGR-5, and C-MYC. Kindlin-2 silencing reduces colonosphere proliferation, invasion, and migration of colonic CSCs. Mechanistically, Kindlin-2 silencing reduces the expression, and nuclear localization of ß-catenin, and decreases ß-catenin target genes such as C-MYC, cyclin D1, DKK-1, and Snail-1. CONCLUSION: Our study delineates the isoform-specific activity of Kindlin-2 in regulating Colonic CSC. Isoform-specific targeting of Kindlin-2 may be a novel strategy to tackle this devastating disease.


Assuntos
Neoplasias do Colo , beta Catenina , Humanos , beta Catenina/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Colo/metabolismo , Integrinas/metabolismo , Células-Tronco Neoplásicas/metabolismo , Isoformas de Proteínas/metabolismo , Via de Sinalização Wnt/genética
4.
Urologia ; 91(2): 261-269, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38159064

RESUMO

INTRODUCTION: One of the most fatal urological malignancies is clear cell renal cell carcinoma (ccRCC), yet little is known about its pathophysiology or prognosis. This study is aimed at obtaining some novel biomarkers with diagnostic and prognostic meaning and may find out potential therapeutic targets for ccRCC. MATERIAL AND METHODS: Using three publically accessible ccRCC gene expression profiles acquired from the Gene Expression Omnibus database, differentially expressed genes (DEG) were discovered and function enrichment analyses were carried out. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were conducted by using the DAVID tool and a protein-protein interaction (PPI) network was constructed and visualized by Cytoscape. Then we identified 10 hub genes using the cytohubba plugin of Cytoscape based on degree score. The mRNA and protein expression of hub genes was analyzed by GEPIA and Human Protein Atlas (HPA) database. Then, prognosis analysis of hub genes was conducted using GEPIA 3.0 which consists of data from The Cancer Genome Atlas (TCGA). RESULTS: We discovered 293 DEG which is highly enriched in several biological processes connected to immune-regulation and pathways linked to tumors, including HIF-1, PI3K-AKT, and metabolic pathways. In particular, C1QA, C1QB, FCER1G, and TYROBP were related to advanced clinical stage, high pathological grade, and poor survival in patients with ccRCC. CONCLUSIONS: Further molecular biological studies are required to confirm the role of the putative biomarkers in human ccRCC. Our work highlighted the hub genes and pathways involved in the progression of ccRCC.


Assuntos
Carcinoma de Células Renais , Biologia Computacional , Neoplasias Renais , Carcinoma de Células Renais/genética , Humanos , Neoplasias Renais/genética , Prognóstico , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica
5.
Curr Cancer Drug Targets ; 23(4): 278-292, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36306454

RESUMO

AIMS: Development of anticancer agents targeting tubulin protein. BACKGROUND: Tubulin protein is being explored as an important target for anticancer drug development. Ligands binding to the colchicine binding site of the tubulin protein act as tubulin polymerization inhibitors and arrest the cell cycle in the G2/M phase. OBJECTIVE: Synthesis and screening of benzotriazole-substituted 2-phenyl quinazolines as potential anticancer agents. METHODS: A series of benzotriazole-substituted quinazoline derivatives have been synthesized and evaluated against human MCF-7 (breast), HeLa (cervical) and HT-29 (colon) cancer cell lines using standard MTT assays. RESULTS: ARV-2 with IC50 values of 3.16 µM, 5.31 µM, 10.6 µM against MCF-7, HELA and HT29 cell lines, respectively displayed the most potent antiproliferative activities in the series while all the compounds were found non-toxic against HEK293 (normal cells). In the mechanistic studies involving cell cycle analysis, apoptosis assay and JC-1 studies, ARV-2 and ARV-3 were found to induce mitochondria-mediated apoptosis. CONCLUSION: The benzotriazole-substituted 2-phenyl quinazolines have the potential to be developed as potent anticancer agents.


Assuntos
Antineoplásicos , Tubulina (Proteína) , Humanos , Tubulina (Proteína)/metabolismo , Relação Estrutura-Atividade , Polimerização , Células HEK293 , Proliferação de Células , Simulação de Acoplamento Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Quinazolinas/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química
6.
Nanomaterials (Basel) ; 14(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38202532

RESUMO

Highly aligned multi-wall carbon nanotubes were investigated with scanning electron microscopy (SEM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) before and after bombardment performed using noble gas ions of different masses (argon, neon and helium), in an ultra-high-vacuum (UHV) environment. Ion irradiation leads to change in morphology, deformation of the carbon (C) honeycomb lattice and different structural defects in multi-wall carbon nanotubes. One of the major effects is the production of bond distortions, as determined by micro-Raman and micro-X-ray photoelectron spectroscopy. We observe an increase in sp3 distorted bonds at higher binding energy with respect to the expected sp2 associated signal of the carbon 1s core level, and increase in dangling bonds. Furthermore, the surface damage as determined by the X-ray photoelectron spectroscopy carbon 1s core level is equivalent upon bombarding with ions of different masses, while the impact and density of defects in the lattice of the MWCNTs as determined by micro-Raman are dependent on the bombarding ion mass; heavier for helium ions, lighter for argon ions. These results on the controlled increase in sp3 distorted bonds, as created on the multi-wall carbon nanotubes, open new functionalization prospects to improve and increase atomic hydrogen uptake on ion-bombarded multi-wall carbon nanotubes.

7.
Sci Rep ; 12(1): 18413, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319798

RESUMO

Gastric cancer has emerged as a key challenge in oncology research as a malignant tumour with advanced stage detection. Apart from surgical management, a pharmacotherapeutic approach to stomach cancer treatment is an appealing option to consider. Andrographolide has been shown to have anticancer and chemosensitizer properties in a variety of solid tumors, including stomach cancer but the exact molecular mechanism is skeptical. In this study, we identified and validated pharmacological mechanism involved in the treatment of GC with integrated approach of network pharmacology and molecular docking. The targets of andrographolide and GC were obtained from databases. The intersected targets between andrographolide and GC-related genes were used to construct protein-protein interaction (PPI) network. Furthermore, mechanism of action of the targets was predicted by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Finally, these results were validated by molecular docking experiments, mRNA and protein expression level. A total of 197 targets were obtained for andrographolide treating GC. Functional enrichment analysis revealed that the target genes were exerted promising therapeutic effects on GC by HIF-1 and PI3K-Akt signaling pathway. The possible mechanism of action is by inactivation of HIF-1 signaling pathway which is dependent on the inhibition of upstream PI3K-AKT pathway. The PPI network identified SRC, AKT1, TP53, STAT3, PIK3CA, MAPK1, MAPK3, VEGFA, JUN and HSP90AA1 as potential hub targets. In addition, these results were further validated with molecular docking experiments. Survival analysis indicated that the expression levels of the hub genes were significantly associated with the clinical prognosis of GC. This study provided a novel approach to reveal the therapeutic mechanisms of andrographolide on GC, making future clinical application of andrographolide in the treatment of GC.


Assuntos
Medicamentos de Ervas Chinesas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Simulação de Acoplamento Molecular , Farmacologia em Rede , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Medicamentos de Ervas Chinesas/farmacologia
8.
Bioorg Med Chem ; 72: 116976, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-36067627

RESUMO

Colchicine binding site represent a crucial target for the anticancer drug development especially in view of emerging drug resistance from the currently available chemotherapeutics. A total of 16 novel 4-N-heterocyclic-2-aryl-6,7,8-trimethoxyquinazolines were synthesized and screened for antiproliferative and tubulin polymerization inhibition potential. The synthesized compounds were evaluated against MCF-7, HeLa and HT-29 cancer cell lines and normal cell line HEK-293 T. In the series, 2­aryl group with 4­bromophenyl substitution displayed IC50 values of 6.37 µM, 17.43 µM, 6.76 µM and 4­chlorophenyl substitution displayed IC50 values of 2.16 µM, 8.53 µM, 10.42 µM against MCF-7, HELA and HT29 cancer cell lines, respectively. In the mechanistic studies involving cell cycle analysis, apoptosis assay and JC-1 studies, both the lead compounds were found to induce mitochondria mediated apoptosis and lead molecule with 4­chlorophenyl substitution displayed significant tubulin polymerization inhibition activity. In the computation studies, lead molecule displayed significant binding affinites in the colchicine domain and showed good thermodynamic stability during 100 ns MD simulation studies. 4-N-Heterocyclic-2-aryl-6,7,8-trimethoxyquinazolines showed appreciable drug like characteristics and can be developed as potent anticancer agents.


Assuntos
Antineoplásicos , Quinazolinas , Moduladores de Tubulina , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Colchicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Células HEK293 , Humanos , Simulação de Acoplamento Molecular , Polimerização , Quinazolinas/química , Relação Estrutura-Atividade , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/química
9.
J Recept Signal Transduct Res ; 42(6): 599-607, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36125981

RESUMO

PI3K/AKT/mTOR pathway is one of the frequently disrupted signaling pathways in renal cell carcinoma (RCC) that plays a significant role in tumor formation, disease progression and therapeutic resistance. Therefore, novel natural molecules targeting the critical proteins of this pathway will provide the best alternative to existing drugs, which are toxic and develops resistance. Recent studies have recognized the anti-cancer therapeutic potential of mycocompounds. The current study is focused on screening various mycocompounds from Astraeus hygrometricus against key cancer signaling proteins phosphoinositide 3-kinase (PI3K), protein kinase B, PKB (AKT1) and mammalian target of rapamycin (mTOR). We also studied in-silico cancer cells cytotoxicity and ADMET (absorption, distribution, metabolism, excretion and toxicity) profiles to elucidate the molecular mechanism against RCC and also to uncover the pharmacokinetic profile of these compounds. Astrakurkurone and Ergosta-4,6, 8-(14) 22-tetraene-3-one were the two most efficacious compounds with highest interaction scores and bonding. These compounds were both active against RCC4 and VMRC-RCZ cell lines of RCC. The ADME profiles of both were satisfactory based on druglikeness and bioavailability score criteria. Thus, this proposed study identified astrakurkurone and ergosta-4,6, 8-(14) 22-tetraene-3-one as potential anticancer drug candidates, and provides comparative structural insight into their binding to the 3 protein kinases.


Assuntos
Produtos Biológicos , Carcinoma de Células Renais , Fungos , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Neoplasias Renais/patologia , Fosfatidilinositol 3-Quinase , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/genética , Serina-Treonina Quinases TOR/genética , Fungos/química , Produtos Biológicos/farmacologia
10.
Indian Pediatr ; 58(1): 25-29, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33452773

RESUMO

OBJECTIVE: To compare the effect of suctioning first or drying first on the composite outcome of hypothermia or respiratory distress in depressed newborns requiring delivery room resuscitation. DESIGN: Open-label, randomized, parallel-group, controlled trial. SETTING: Delivery room and neonatal intensive care unit of a tertiary-care teaching hospital. PATIENTS: Depressed newborns (n=154) requiring initial steps of resuscitation at birth. Intervention: During delivery room resuscitation eligible new-borns were randomly allocated to receive either suctioning first or drying first (77 newborns in each group). MAIN OUTCOME MEASURE: Composite incidence of hypothermia at admission or respiratory distress at 6 hours of age. RESULTS: Both groups were comparable with regard to maternal and neonatal characteristics. Composite outcome was similar in both the groups [46 (59.7%) vs 55 (71.4%)] in suctioning first and drying first, respectively [RR (95% CI), 0.84 (0.66-1.05); P=0.13]. Incidence of hypothermia, respiratory distress at admission and oxygen saturation at 6 hours were also similar. On admission to NICU, hypothermia was observed in 26 (33.8%) neonates in suctioning first group and 33 (42.8%) neonates in drying first group but by one hour of age the proportion of hypothermic neonates was 13 (16.9%) and 14 (18.1%), respectively. CONCLUSION: In newborns depressed at birth, the sequence of performing initial steps, whether suctioning first or drying first, had comparable effect on composite outcome of hypothermia at admission or respiratory distress at 6 hours of age.


Assuntos
Salas de Parto , Hipotermia , Feminino , Humanos , Hipotermia/epidemiologia , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Gravidez , Ressuscitação , Sucção
12.
Environ Sci Pollut Res Int ; 25(31): 31691-31704, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30209766

RESUMO

In the present study, we correlated the various lifestyle habits and their associated mutations in cell cycle (P21 and MDM2) and DNA damage repair (MLH1) genes to investigate their role in gastric cancer (GC). Multifactor dimensionality reduction (MDR) analysis revealed the two-factor model of oral snuff and smoked meat as the significant model for GC risk. The interaction analysis between identified mutations and the significant demographic factors predicted that oral snuff is significantly associated with P21 3'UTR mutations. A total of five mutations in P21 gene, including three novel mutations in intron 2 (36651738G > A, 36651804A > T, 36651825G > T), were identified. In MLH1 gene, two variants were identified viz. one in exon 8 (37053568A > G; 219I > V) and a novel 37088831C > G in intron 16. Flow cytometric analysis predicted DNA aneuploidy in 07 (17.5%) and diploidy in 33 (82.5%) tumor samples. The G2/M phase was significantly arrested in aneuploid gastric tumor samples whereas high S-phase fraction was observed in all the gastric tumor samples. This study demonstrated that environmental chemical carcinogens along with alteration in cell cycle regulatory (P21) and mismatch repair (MLH1) genes may be stimulating the susceptibility of GC by altering the DNA content level abnormally in tumors in the Mizo ethic population.


Assuntos
Carcinógenos/toxicidade , Ciclo Celular/genética , Neoplasias Gástricas/epidemiologia , Proteínas Adaptadoras de Transdução de Sinal , Reparo de Erro de Pareamento de DNA , Reparo do DNA , Genes cdc , Humanos , Estilo de Vida , Proteína 1 Homóloga a MutL , Mutação , Neoplasias Gástricas/genética
13.
Fish Physiol Biochem ; 43(1): 89-102, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27522494

RESUMO

Changes in the expression of a number of hsp genes in minnow Puntius sophore collected from a hot spring run-off (Atri hot spring in Odisha, India; 20o09'N 85°18'E, 36-38 °C) were investigated to study the upper thermal acclimation response under heat stress, using same species from aquaculture ponds (water temperature 27 °C) as control. Expression of hsp genes was analyzed in both groups using RT-qPCR, which showed up-regulation of hsp90 (2.1-fold) and hsp47 (2.5-fold) in hot spring run-off fishes, whereas there was no alteration in expression of other hsps. As the fish inhabit the hot spring run-off area for very long duration, they could have adapted to the environment. To test this hypothesis, fishes collected from hot spring run-off were divided into two groups; one was heat-shocked at 41 °C/24 h, and the other was acclimatized at 27 °C/24 h. Up-regulation of all the hsps (except hsp78) was observed in the heat-shocked fishes, whereas expression of all hsps was found to be down-regulated to the basal level in fishes maintained at 27 °C/24 h. Pathway analysis showed that the expressions of all the hsps except hsp90 are regulated by the transcription factor heat shock factor 1 (Hsf1). This study showed that hsp90 and hsp47 play an important role in Puntius sophore for surviving in the high-temperature environment of the hot spring run-off. Additionally, we show that plasticity in hsp gene expression is not lost in the hot spring run-off population.


Assuntos
Cyprinidae/genética , Proteínas de Choque Térmico HSP47/genética , Proteínas de Choque Térmico HSP90/genética , Fontes Termais , Animais , Ecossistema , Perfilação da Expressão Gênica , Resposta ao Choque Térmico , Fontes Termais/análise , Temperatura Alta , Metais/análise , Regulação para Cima
14.
Helicobacter ; 21(6): 523-535, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27006283

RESUMO

BACKGROUND: The aim of this study was to evaluate the risk of gastric cancer associated with individual or combined glutathione S-transferases (GSTs) polymorphism and their interaction with environmental factors. MATERIALS AND METHODS: Genotyping by PCR was carried out for 80 cases and controls each for GSTM1, GSTT1, and GSTP1 polymorphism and mapped for gene-environment association studies. The samples were subjected to pathogen detection and GSTP1 expression for analyzing their association with different genotypes. Logistic regression analyses were conducted to compute the influence of both genetic and environmental factors for gastric cancer. MDR analysis was performed to assess the risk of gastric cancer by studying the gene-gene and gene-environment effect on the basis of GST genotyping and GSTP1 gene expression. RESULTS: Infection with Helicobacter pylori and CagA+ strains was more frequent in patients with GSTM1/T1 null genotype. Intake of high fermented fat and smoked meat was found to be significantly associated with gastric cancer. The G/G, A/G (rs1695), and T/T (rs1138272) were found to be significantly associated with low expression of GSTP1 gene in cancer tissue. CONCLUSION: Presence of H. pylori with CagA genotype showed significant individual effect with GSTT1 polymorphism as well as strong synergistic effect in gastric cancer risk. Majority of the gastric cancer samples showed significant negative expression in G/G, A/G (rs1695), and T/T (rs1138272) genotypes. This study shows that GST gene polymorphism was significantly relevant for determining the individual susceptibility to gastric cancer.


Assuntos
Predisposição Genética para Doença , Glutationa S-Transferase pi/genética , Infecções por Helicobacter/complicações , Neoplasias Gástricas/genética , Adulto , Idoso , Povo Asiático , Feminino , Técnicas de Genotipagem , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo Genético , Medição de Risco , Neoplasias Gástricas/epidemiologia
15.
Biochem Genet ; 54(1): 41-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26407578

RESUMO

The enzymes encoded by glutathione S-transferase mu 1 (GSTM1) and theta 1 (GSTT1) genes are involved in the metabolism of wide range of carcinogens that are ubiquitous in the environment. Homozygous deletions of the GSTM1 and GSTT1 genes are commonly found and result in lack of enzyme activity. This study was undertaken to evaluate the association between GSTM1, GSTT1 and GSTP1 gene polymorphism and breast cancer risk in Mizoram population. Odd ratio (OR) and 95% confidence interval (CI) from conditional logistic regression model were used to estimate the association between genetic polymorphism and breast cancer risk. The GSTM1 and GSTT1 null genotypes were associated with an increased risk of breast cancer [OR = 10.80 (95% CI 1.16-100.43)]. The risk of breast cancer associated with the GSTT1 null genotype was observed to be low among postmenopausal women. When considered together, GSTM1 and GSTT1 genotypes were found to be associated with an increased risk of breast cancer. The relationship between GSTM1 and GSTT1 gene deletions and breast cancer risk was substantially altered by consumption of Smoked Meat/Vegetable. In the present study, GSTP1Ile105Val (rs1695) polymorphism was related to breast cancer susceptibility or phenotype. Our data provides evidence for substantially increased risk of breast cancer associated with GSTM1 and/or GSTT1 homozygous gene deletions in Mizoram population.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Glutationa Transferase/genética , Polimorfismo Genético , Adulto , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etnologia , Feminino , Genótipo , Humanos , Índia/epidemiologia , Pessoa de Meia-Idade
16.
Food Chem ; 132(3): 1296-1304, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29243614

RESUMO

A dimeric serine protease Neriifolin S of molecular mass 94kDa with milk clotting activity has been purified from the latex of Euphorbia neriifolia by anion exchange and size-exclusion chromatography. It hydrolyses peptidyl substrates l-Ala-pNA with highest affinity (Km of 0.195mM) and physiological efficiency (Kcat/Km of 144.5mMs). Enzyme belongs to the class of neutral proteases with pI value of 6.8, optimal proteolytic activity displayed at pH 9.5 and temperature 45°C. Its proteolytic activity is strongly stimulated in the presence of Ca+2 ions and exclusively inhibited by serine protease inhibitors. Enzyme is fairly stable toward chemical denaturants, pH and temperature. The apparent Tm, was found to be 65°C. Thermal inactivation follow first order kinetics with activation energy (Ea), activation enthalpy (ΔH∗), free energy change (ΔG∗) and entropy (ΔS∗) of 27.54kJmol-1, 24.89kJmol-1, -82.34kJmol-1 and 337.20Jmol-1K-1.

17.
Phytochemistry ; 70(10): 1210-6, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19683318

RESUMO

A multi-functional enzyme ICChI with chitinase/lysozyme/exochitinase activity from the latex of Ipomoea carnea subsp. fistulosa was purified to homogeneity using ammonium sulphate precipitation, hydrophobic interaction and size exclusion chromatography. The enzyme is glycosylated (14-15%), has a molecular mass of 34.94 kDa (MALDI-TOF) and an isoelectric point of pH 5.3. The enzyme is stable in pH range 5.0-9.0, 80 degrees C and the optimal activity is observed at pH 6.0 and 60 degrees C. Using p-nitrophenyl-N-acetyl-beta-D-glucosaminide, the kinetic parameters K(m), V(max), K(cat) and specificity constant of the enzyme were calculated as 0.5mM, 2.5 x 10(-8)mol min(-1)microg enzyme(-1), 29.0 s(-1) and 58.0mM(-1)s(-1) respectively. The extinction coefficient was estimated as 20.56 M(-1)cm(-1). The protein contains eight tryptophan, 20 tyrosine and six cysteine residues forming three disulfide bridges. The polyclonal antibodies raised and immunodiffusion suggests that the antigenic determinants of ICChI are unique. The first fifteen N-terminal residues G-E-I-A-I-Y-W-G-Q-N-G-G-E-G-S exhibited considerable similarity to other known chitinases. Owing to these unique properties the reported enzyme would find applications in agricultural, pharmaceutical, biomedical and biotechnological fields.


Assuntos
Quitinases/química , Quitinases/metabolismo , Ipomoea/enzimologia , Látex/química , Sequência de Aminoácidos , Glicosilação , Ponto Isoelétrico , Cinética , Dados de Sequência Molecular , Especificidade por Substrato
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