21 research outputs found
The hepatoprotective effect of jaboticaba peel powder in a rat model of type 2 Diabetes Mellitus involves the modulation of thiol/disulfide redox state through the upregulation of glutathione synthesis
Jaboticaba peel powder (JPP) is rich in bioactive compounds, mainly soluble and insoluble polyphenols with great antioxidant properties. ,e aim of this study is to evaluate the effects of JPP supplementation on the oxidative stress and hepatic damage in a rat model of type 2 diabetes mellitus (T2DM). Diabetic rats received vehicle or JPP at 2.7 (JPP-I), 5.4 (JPP-II), or 10.8 (JPP-III) g/L in drinking water during 8 weeks. JPP-III attenuated hyperglycaemia and dyslipidemia increased by 86% the liver content of nonprotein thiol groups and by 90% the GSH/GSSG ratio by activating glutathione synthesis. Accordingly, JPP supplementation prevented the loss of activity of the sulfhydryl-dependent enzyme δ-aminolaevulinic acid dehydratase and attenuated hepatic injury assessed by the reduction of serum aspartate aminotransferase activity and liver hypertrophy. Our results support that JPP supplementation to T2DM rats decreases hepatic damage most likely by increasing glutathione synthesis and modulating the thiol/disulfide redox balance
The relationships between exogenous and endogenous antioxidants with the lipid profile and oxidative damage in hemodialysis patients
Background: We sought to investigate the relationships among the plasma levels of carotenoids, tocopherols, endogenous antioxidants, oxidative damage and lipid profiles and their possible effects on the cardiovascular risk associated with hemodialysis (HD) patients. Methods: The study groups were divided into HD and healthy subjects. Plasma carotenoid, tocopherol and malondialdehyde (MDA) levels, as well as erythrocyte reduced glutathione (GSH), were measured by HPLC. Blood antioxidant enzymes, kidney function biomarkers and the lipid profiles were analyzed by spectrophotometric methods. Results: Plasma lycopene levels and blood glutathione peroxidase (GPx) activity were significantly decreased in HD patients compared with healthy subjects. Total cholesterol, low-density lipoprotein cholesterol (LDL-c), creatinine, urea, MDA, GSH, superoxide dismutase (SOD) and catalase (CAT) were significantly increased in HD (p < 0.05). Lycopene levels were correlated with MDA (r = -0.50; p < 0.01), LDL-c (r = -0.38; p = 0.01) levels, the LDL-c/HDL-c index (r = -0.33; p = 0.03) and GPx activity (r = 0.30; p = 0.03). Regression models showed that lycopene levels were correlated with LDL-c (β estimated = -31.59; p = 0.04), while gender was correlated with the TC/HDL-c index and triglycerides. Age did not present a correlation with the parameters evaluated. GPx activity was negatively correlated with MDA levels and with the LDL-c/HDL-c and CT/HDL-c indexes. Conclusions: Lycopene may represent an additional factor that contributes to reduced lipid peroxidation and atherogenesis in hemodialysis patients
Quantificação simultânea de indicadores biológicos de exposição a solventes orgânicos por cromatografia lÃquida de alta eficiência
Biological monitoring is very important to guarantee health to workers. This method was developed for simultaneous determination of xylene, toluene, styrene and ethylbenzene metabolites. It involves only dilution and centrifugation of urine samples and improved chromatographic conditions. Analyses show recovery > 95%; r² > 0.99; intermediate precision CV% < 6% and % bias < ±10. Exposed subjects presented at least three metabolites in urine. The method proved to be feasible, reliable and important in biological monitoring, especially in exposure to organic solvent mixtures
Simultaneous quantification of organic solvent biomarkers by high performance liquid chromatography
Biological monitoring is very important to guarantee health to workers. This method was developed for simultaneous determination of xylene, toluene, styrene and ethylbenzene metabolites. It involves only dilution and centrifugation of urine samples and improved chromatographic conditions. Analyses show recovery ≥ 95%; r2 > 0.99; intermediate precision CV% < 6% and % bias < ±10. Exposed subjects presented at least three metabolites in urine. The method proved to be feasible, reliable and important in biological monitoring, especially in exposure to organic solvent mixtures
Simultaneous quantification of organic solvent biomarkers by high performance liquid chromatography
Biological monitoring is very important to guarantee health to workers. This method was developed for simultaneous determination of xylene, toluene, styrene and ethylbenzene metabolites. It involves only dilution and centrifugation of urine samples and improved chromatographic conditions. Analyses show recovery ≥ 95%; r2 > 0.99; intermediate precision CV% < 6% and % bias < ±10. Exposed subjects presented at least three metabolites in urine. The method proved to be feasible, reliable and important in biological monitoring, especially in exposure to organic solvent mixtures
Procaine : pharmacological and toxicological effects
A procaÃna é um anestésico local utilizado há décadas por dentistas. Atualmente, tem sido utilizada para tratar a depressão, aumentar a libido e agir em processos inflamatórios e no emagrecimento, entre outras utilidades. Porém, existem crÃticas acerca do tratamento com essa substância isolada ou associada. A falta de embasamento cientÃfico para sua utilização torna seu uso infundado e subjetivo, podendo ser muitas vezes nocivo ao indivÃduo. Portanto, este artigo tem como objetivo buscar evidências cientÃficas das ações sistêmicas da procaÃna que comprovem seus efeitos para tais finalidades. Foi realizado um levantamento na literatura cientÃfica e concluiu-se que, exceto por um possÃvel efeito antidepressivo, até o momento não existem dados que comprovem os efeitos alegados para a procaÃna. Devido a isso, os usos atuais não se justificariam no tratamento de doenças crônicas ou no combate ao envelhecimento. Além disso, esta revisão enfatiza a necessidade da realização de estudos para avaliação farmacológica e toxicológica da procaÃna, bem como a necessidade de aplicar-se ensaios in vivo e in vitro na avaliação da segurança de preparações farmacêuticas que contenham essa substância, a fim de comprovar as inúmeras indicações de uso
Bixin and Norbixin Have Opposite Effects on Glycemia, Lipidemia, and Oxidative Stress in Streptozotocin-Induced Diabetic Rats
The present study investigated the effects of oral administration of annatto carotenoids (bixin (BIX) and norbixin (NBIX)) on glucose levels, lipid profiles, and oxidative stress parameters in streptozotocin (STZ)-induced diabetic rats. Animals were treated for 30 days in the following groups: nondiabetic control, diabetic vehicle, diabetic 10 mg/kg BIX, diabetic 100 mg/kg BIX, diabetic 10 mg/kg NBIX, diabetic 100 mg/kg NBIX, diabetic metformin, and diabetic insulin. Blood glucose, LDL cholesterol, and triglyceride levels were reduced in the diabetic rats treated with BIX. BIX treatment prevented protein oxidation and nitric oxide production and restored superoxide dismutase activity. NBIX treatment did not change most parameters assessed, and at the highest dose, it increased LDL cholesterol and triglycerides levels and showed prooxidant action (increased protein oxidation and nitric oxide levels). These findings suggested that BIX could have an antihyperglycemic effect, improve lipid profiles, and protect against damage induced by oxidative stress in the diabetic state. Because NBIX is a water-soluble analog of BIX, we propose that lipophilicity is crucial for the protective effect of annatto carotenoids against streptozotocin-induced diabetes
Quantificação sérica de vitamina C por CLAE-UV e estudo de estabilidade
Vitamin C, an exogenous antioxidant, is essential to human health. In this study, a method was validated to serum vitamin C quantification by HPLC-UV. Its stability with and without the use of tris [2-carboxy-ethyl] phosphine hydrochloride (TCEP), at -20 and -80 °C, in serum and supernatant were also evaluated. Analysis showed r² > 0.99, precision CV% < 15% and % bias < 15%, being linear, precise and accurate. The stability test revealed that using TCEP in serum storage at -20 and -80 °C or in supernatant at -80 °C the vitamin C levels remain stable for 30 and 12 days, respectively
Astaxanthin prevents changes in the activities of thioredoxin reductase and paraoxonase in hypercholesterolemic rabbits
Serum quantification of vitamin c by hplc-uv and stability study
Vitamin C, an exogenous antioxidant, is essential to human health. In this study, a method was validated to serum vitamin C quantification by HPLC-UV. Its stability with and without the use of tris [2-carboxy-ethyl] phosphine hydrochloride (TCEP), at-20 and -80 ºC, in serum and supernatant were also evaluated. Analysis showed r2 > 0.99, precision CV% < 15% and % bias < 15%, being linear, precise and accurate. The stability test revealed that using TCEP in serum storage at-20 and -80 ºC or in supernatant at -80 ºC the vitamin C levels remain stable for 30 and 12 days, respectively