University of Madras

About: University of Madras is a education organization based out in Chennai, Tamil Nadu, India. It is known for research contribution in the topics: Ring (chemistry) & Lipid peroxidation. The organization has 8496 authors who have published 11369 publications receiving 211152 citations. The organization is also known as: Madras University & University of Chennai.

Hesperidin-mediated expression of Nrf2 and upregulation of antioxidant status in senescent rat heart

Abstract: Objectives Oxidative stress is recognized as a key element responsible for the development of age-related pathologies A declining endogenous defence system during senescence dictates the need for supplementation with exogenous antioxidants through diet Hesperidin is a naturally occurring flavonone present in citrus fruits and has been shown to have many biological properties, including antioxidant activity We investigated whether hesperidin supplementation could be valuable in protecting cardiac tissue of aged rats against age-related increase in oxidative stress, as well as the mechanism by which it can boost the antioxidant status of the cell Methods The activity of antioxidant enzymes, mRNA expression of Nrf2, protein levels of superoxide dismutase and catalase were measured using standard protocols Key findings Hesperidin treatment effectively protected aged rat heart by increasing the activity of enzymic antioxidants Hesperidin upregulated the protein levels of nuclear factor erythroid 2-related factor 2, which is responsible for maintaining the antioxidant status of the cell Conclusions Hesperidin could be useful in protecting cardiomyocytes against age-related increase in oxidative stress mediated by Nrf2 upregulation

Methanol-induced oxidative stress in rat lymphoid organs.

Abstract: Methanol is primarily metabolized by oxidation to formaldehyde and then to formate. These processes are accompanied by formation of superoxide anion and hydrogen peroxide. This paper reports data on the effect of methanol on antioxidant status and lipid peroxidation in lymphoid organs such as the spleen, thymus, lymph nodes and bone marrow of rats. Male Wistar albino rats were intoxicated with methanol (2.37 g/kg b.w intraperitoneally) for detecting toxicity levels for one day, 15 d and 30 d, respectively. Administration of methanol at 15 and 30 d significantly (p<0.05) increased lipid peroxidation and decreased the enzymatic (superoxide dismutase, catalase, glutathione peroxidase) and non-enzymatic antioxidants (reduced glutathione and vitamin C) in lymphoid organs. However, lipid peroxidation and enzymatic and non-enzymatic antioxidants in the acute methanol exposed group animals were found to be significantly (p<0.05) increased. In one day methanol intoxication, the levels of free radicals initially increased, and to remove these free radicals, antioxidants levels were elevated, which generally prevented oxidative cell damage. But in longer periods of intoxication, when the generation of reactive free radicals overwhelmed the antioxidant defense, lipid peroxidation increased. Further, decreased antioxidants in 15 and 30 d methanol intoxication may have been due to overutilization of non-enzymatic and enzymatic antioxidants to scavenge the products of lipid peroxidation. In addition, the liver and kidney markers of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea and creatinine significantly increased. This study concludes that exposure to methanol causes oxidative stress by altering the oxidant/antioxidant balance in lymphoid organs of the rat.

High prevalence of HIV, HIV/hepatitis C virus coinfection, and risk behaviors among injection drug users in Chennai, India: a cause for concern.

Abstract: Objective:To estimate the prevalence of HIV and hepatitis C virus (HCV) and hepatitis B virus (HBV) coinfections and current risk behaviors among HIV-positive and -negative injection drug users (IDUs) in Chennai, India.Methods:Cross-sectional analysis of a convenience sample of 912 IDUs recruited be

Antiproliferative potential of gallic acid against diethylnitrosamine-induced rat hepatocellular carcinoma.

Abstract: One of the focuses in current cancer chemoprevention studies is the search for nontoxic chemopreventive agents that inhibit the initiation of malignant transformation. Cancer biomarkers are quantifiable molecules involved in the physiologic or pathologic events occurring between exposure to carcinogens and the development, progression of cancer. Biomarkers may be the consequence of a continuous process, such as increased cell mass, or a discrete event, such as genetic mutation. Analysis of tumor markers can be used as an indicator of tumor response to therapy. Gallic acid is a naturally available polyphenol, possess strong antioxidant activity with a capacity to inhibit the formation of tumors in several cancer models. In the present study, we investigated the antiproliferative effect of gallic acid during diethylnitrosamine (DEN)-induced hepatocellular carcinoma (HCC) in male wistar albino rats. DEN treatment resulted in increased levels of aspartate transaminase, alanine transaminase, alkaline phosphatase, acid phosphatase, lactate dehydrogenase, gamma-glutamyltransferase, 5′-nucleotidase, bilirubin, alpha-fetoprotein, carcinoembryonic antigen, argyophillic nucleolar organizing regions, and proliferating cell nuclear antigen. Gallic acid treatment significantly attenuated these alterations and decreased the levels of AgNORs and PCNA. These finding suggests that gallic acid is a potent antiproliferative agent against DEN-induced HCC.