title: Green tea extract attenuates cyclosporine A-induced oxidative stress in rats.
abstract: Cyclosporine A (CsA) nephrotoxicity underweighs the therapeutic benefits of such a powerful immunosuppressant. Whether oxidative stress plays a role in such toxicity is not well delineated. We investigated the potential of green tea extract (GTE) to attenuate CsA-induced renal dysfunction in rats. Three main groups of Sprague-Dawley rats were used: CsA, GTE, and GTE plus CsA-receiving animals. Corresponding control groups were also used. CsA was administered in a dose of 20mg kg(-1) day(-1), i.p., for 21 days. In the GTE/CsA groups, the rats received different concentrations of GTE (0.5, 1.0 and 1.5%), as their sole source of drinking water, 4 days before and 21 days concurrently with CsA. The GTE group was treated with 1.5% concentration of GTE only for 25 days. A concomitant administration of GTE, to CsA receiving rats, markedly prevented the generation of thiobarbituric acid-reacting substances (TBARS) and significantly attenuated CsA-induced renal dysfunction as assessed by estimating serum creatinine, blood urea nitrogen, uric acid and urinary excretion of glucose. A considerable improvement in terms of reduced glutathione content and activity of antioxidant enzymes in the kidney homogenate of the GTE/CsA-receiving rats was observed. The activity of lysosomal enzymes, N-acetyl-beta-glucosaminidase, beta-glucuronidase and acid phosphatase was significantly inhibited following GTE co-administration. Our data prove the role of oxidative stress in the pathogenesis of CsA-induced kidney dysfunction. Supplementation of GTE could be useful in reducing CsA nephrotoxicity in rats. However, clinical studies are warranted to investigate such an effect in human subjects.
authors.affiliation: Tumor Marker Oncology Research Unit, Biochemistry Department, Cairo, Egypt.
authors.forename: A M
authors.initials: AM
authors.lastname: Mohamadin
authors.forename: H A
authors.initials: HA
authors.lastname: El-Beshbishy
authors.forename: M A
authors.initials: MA
authors.lastname: El-Mahdy
mesh_terms: D000818:Animals; D016572:Cyclosporine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects* / Q000502:physiology; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013662:Tea
chemical_list: D010936:Plant Extracts; D013662:Tea; D016572:Cyclosporine