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1.
J Vis Exp ; (190)2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36622010

RESUMO

Here, we present a visual representation of standard procedures to collect population-level data on personal exposures to household air pollution (HAP) from two different study sites in a resource-constrained setting of Tamil Nadu, India. Particulate matter PM2.5 (particles smaller than 2.5 microns in aerodynamic diameter), carbon monoxide (CO), and black carbon (BC) were measured in pregnant mothers (M), other adult women (OAW), and children (C) at various times over a 4 year period. In addition, stove usage monitoring (SUMs) with data-logging thermometers and ambient measurements of air pollution were carried out. Furthermore, the feasibility of collecting biological samples (urine and dried blood spots [DBSs]) from study participants at the field sites was successfully demonstrated. Based on findings from this and earlier studies, the methods used here have enhanced the data quality and avoided issues with household air pollution and biological sample collection in resource-constrained situations. The procedures established may be a valuable educational tool and resource for researchers conducting similar air pollution and health studies in India and other low- and middle-income countries (LMICs).


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Adulto , Criança , Gravidez , Humanos , Feminino , Poluentes Atmosféricos/análise , Exposição Ambiental/análise , Índia , Material Particulado/análise , Coleta de Dados
2.
Cell Biol Toxicol ; 37(4): 611-631, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33219891

RESUMO

Identifying drug candidates to target cellular events/signaling that evades von Hippel-Lindau tumor suppressor (VHL) gene interaction is critical for the cure of renal cell carcinoma (RCC). Recently, we characterized a triterpene-squalene derived from marine brown alga. Herein, we investigated the potential of squalene in targeting HIF-signaling and other drivers of RCC progression. Squalene inhibited cell proliferation, induced cell dealth and reverted the cells' metastatic state (migration, clonal expansion) independent of their VHL status. Near-identical inhibition of HIF-1α and HIF-2α and the regulation of downstream targets in VHL wild type and mutant cell lines demonstrated squalene efficacy beyond VHL-HIF interaction. In a rat model of chemically induced RCC, squalene displayed chemopreventive capabilities by substantial reversal of lipid peroxidation, mitochondrial redox regulation, maintaining ∆ψm, inflammation [Akt, nuclear factor κB (NF-κB)], angiogenesis (VEGFα), metastasis [matrix metalloproteinase 2 (MMP-2)], and survival (Bax/Bcl2, cytochrome-c, Casp3). Squalene restored glutathione, glutathione reductase, glutathione-s-transferase, catalase, and superoxide dismutase and stabilized alkaline phosphatase, alkaline transaminase, and aspartate transaminase. The correlation of thiobarbituric acid reactive substance with VEGF/NF-κB and negative association of GSH with Casp3 show that squalene employs reduction in ROS regulation. Cytokinesis-block micronuclei (CBMN) assay in VHLwt/mut cells revealed both direct and bystander effects of squalene with increased micronucleus (MN) frequency. Clastogenicity analysis of rat bone marrow cells demonstrated an anti-clastogenic effect of squalene, with increased polychromatic erythrocytes (PCEs), decreased MNPCE,s and MN normochromatic erythrocytes. Squalene could effectively target HIF signaling that orchestrate RCC evolution. The efficacy of squalene is similar in VHLwt and VHLmut RCC cells, and hence, squalene could serve as a promising drug candidate for an RCC cure beyond VHL status and VHL-HIF interaction dependency. Summary: Squalene derived from marine brown algae displays strong anti-cancer (RCC) activity, functionally targeting HIF-signaling pathway, and affects various cellular process. The significance of squalene effect for RCC is highlighted by its efficiency beyond VHL status, designating itself a promising drug candidate. Graphical abstract.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Carcinoma de Células Renais/tratamento farmacológico , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia , Metaloproteinase 2 da Matriz , Ratos , Esqualeno , Proteína Supressora de Tumor Von Hippel-Lindau/genética
3.
Environ Toxicol ; 33(11): 1135-1142, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30126067

RESUMO

In our previous work, we assessed the ameliorative effect of crude extract from Padina boergesenii. In this report, we have extended these study by fractionating the methanol extract with methanol:ethylacetate (1:3,v/v) (MME-F) and assessed the cytotoxic effect of MME-F fraction in human renal carcinoma cell lines (A498 and ACHN). The fraction had time-and dose-dependent inhibition of cancer cell proliferation, migration with deceleration of cancer growth at EC50 -22.73 µg in A498 and 26.43 µg in ACHN cells. Cells treated at EC50 value 25 µg displayed twofold greater ability to induce early and late stage of apoptosis. The cells treated with polyphenolic fraction (MME-F) induced cell cycle arrest at G2/M phase. HPLC/DAD chromatographic procedures quantified polyphenols from active fraction (MME-F). These data revealed the functional activity of polyphenols from brown alga, P. boergesenii as a potent inhibitor of cancer proliferation with induction of apoptosis, it suggest their applicability in preventing cancer metastasis.


Assuntos
Carcinoma de Células Renais/patologia , Extratos Celulares/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Renais/patologia , Phaeophyceae/química , Polifenóis/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Extratos Celulares/química , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Humanos , Polifenóis/química
4.
Environ Toxicol ; 30(8): 865-76, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-24458998

RESUMO

The aim of this study was to evaluate the antioxidant activities of diethyl ether (DEE) and methanol (M) extracts from brown alga Padina boergesenii using in vitro and in vivo antioxidant assay, which may help to relate the antioxidant properties with the possible outline of its ameliorative effect. M extract showed higher radical scavenging activity through ferric reducing antioxidant power 139.11 µmol tannic acid equivalent/g; DPPH 71.32 ± 0.56%; deoxyribose radical 88.31 ± 0.47%, and total antioxidant activity 0.47 ± 0.02 mg ascorbic acid equivalents/g. Oxidative red blood cell (RBC) hemolysis inhibition rate was significantly higher in M extract (150 mg/kg body weight) in reference to total phenolic content (r = 0.935). Rats administered with DEE and M extracts (150 mg/kg body weight) for seven days before the administration of ferric nitrilotriacetate (9 mg of Fe/mg/kg bodyweight). Rats pretreated with extracts significantly changed the level of renal microsomal lipid peroxidation, glutathione, and antioxidant enzymes in post-mitochondrial supernatant (P < 0.05). Ameliorative effect of extracts against renal oxidative damage was evident in rat kidney through changes in necrotic and epithelial cells. HPTLC technique has identified the presence of rutin with reference to retardation factor (Rf ) in both the extracts. These findings support the source of polyphenols (rutin) from P. boergesenii had potent antioxidant activity; further work on isolation of bioactive compounds can be channeled to develop as a natural antioxidant.


Assuntos
Antioxidantes/farmacologia , Compostos Férricos/antagonistas & inibidores , Compostos Férricos/toxicidade , Radicais Livres/toxicidade , Hemólise/efeitos dos fármacos , Nefropatias/induzido quimicamente , Nefropatias/prevenção & controle , Ácido Nitrilotriacético/análogos & derivados , Estresse Oxidativo/efeitos dos fármacos , Phaeophyceae/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Animais , Desoxirribose/química , Desoxirribose/farmacologia , Células Epiteliais/efeitos dos fármacos , Feminino , Técnicas In Vitro , Nefropatias/metabolismo , Microssomos/efeitos dos fármacos , Necrose , Ácido Nitrilotriacético/antagonistas & inibidores , Ácido Nitrilotriacético/toxicidade , Ratos , Ratos Wistar , Rutina/análise , Taninos/farmacologia
5.
J Thorac Cardiovasc Surg ; 148(2): 515-520.e2, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24332189

RESUMO

OBJECTIVES: To identify novel predictors for coronary artery bypass grafting failure, we probed for associations with known clinical and biochemical risk factors for atherosclerosis. We also used microarray analysis to identify novel single nucleotide polymorphisms to better understand the genetics and pathogenesis of graft occlusion. METHODS: The present study was a nested case-control substudy of the Radial Artery Patency Study 5-year follow-up data. From 1996 to 2001, 87 patients underwent coronary artery bypass grafting. Of these, 26 patients (29.9%) had an occluded study graft (saphenous vein or radial artery) at 8.0 ± 1.1 years. The clinical parameters, late angiography, blood biomarker levels, and surgical outcomes data were included in a multivariate analysis to determine the independent predictors of graft failure. RESULTS: The risk factors of graft failure were fibrinogen (odds ratio [OR], 3.94; 95% confidence interval [CI], 1.33-11.63; P = .01), creatinine (OR, 1.06; 95% CI, 1.02-1.10; P = .006), and diabetes mellitus (OR, 5.15; 95% CI, 1.08-24.59; P = .04). High-density lipoprotein (OR, 0.74; 95% CI, 0.53-1.02; P = .06) was weakly protective; however, low-density lipoprotein and total cholesterol were not predictors. We then identified the association of several human single nucleotide polymorphisms with graft failure, including mutations in glutathione-S-transferase α3. Human coronary arteries and bypass grafts demonstrated increased protein expression of glutathione-S-transferase α3, a known cardioprotective factor, in the atherosclerotic regions and surrounding adventitial tissues. CONCLUSIONS: We identified diabetes as a potential clinical predictor and plasma fibrinogen, creatinine, and high-density lipoprotein as potential novel biomarkers. These might help risk stratify patients for the development of graft failure. We also demonstrated a novel association between glutathione-S-transferase α3 and graft failure.


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Creatinina/sangue , Fibrinogênio/análise , Glutationa Transferase/genética , Oclusão de Enxerto Vascular/etiologia , Lipoproteínas HDL/sangue , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Angiografia Coronária , Feminino , Perfilação da Expressão Gênica , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Oclusão de Enxerto Vascular/sangue , Oclusão de Enxerto Vascular/diagnóstico por imagem , Oclusão de Enxerto Vascular/genética , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Fenótipo , Fatores de Risco , Falha de Tratamento , Grau de Desobstrução Vascular/genética
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