ABSTRACT
To examine the effect of green tea extract on body weight, serum levels of glucose, and lipids in streptozotocin-induced diabetic rats. This experimental study was carried out in the Diabetes Research Center, Ahvaz University of Medical Sciences, Ahvaz, Iran from January 2011 to March 2011. Forty-eight male wistar rats[200-250g] were divided randomly into 6 groups. Diabetes was induced by a single intraperitoneal injection of stereptozotocin [55 mg/kg]. The experimental groups received alcohol extract of green tea leaves [100 mg/kg and 200 mg/kg] for 4 weeks and the body weight of animals were measured every day. Finally, blood samples were collected and analyzed for glucose and lipid profile levels. Administration of green tea extract caused a significant decrease in serum glucose and total cholesterol levels and significantly improved the body weight loss in diabetic rats treated with 200 mg/kg green tea in comparison to diabetic control group. No significant changes were observed in triglyceride [p=0.04], low-density-lipoprotein cholesterol [p=0.000], and high-density-lipoprotein cholesterol levels [p=0.01] following intervention. It appears that green tea extract had both antihyperglycemic and hypocholesterolmic effects in diabetic rats, although further work is needed to determine their mechanism
ABSTRACT
To evaluate the hypouricemic and antioxidant effects of Allium cepa Lilliaceae [Allium cepa L.] and quercetin in normal and hyperuricemic rats. The following study was conducted in the Department of Nutrition and Biochemistry, Tehran University of Medical Science, Iran, between May 2007 and March 2008. A total of 48 male Wistar rats [body weights: 180-200 g] were randomly divided into 8 equal groups including normal; normal + Allium cepa L. [5g/kg]; normal + quercetin [5mg/kg]; normal + allopurinol [5mg/kg]; hyperuricemic; hyperuricemic + Allium cepa L. [5g/kg]; hyperuricemic + quercetin [5mg/kg]; hyperuricemic + allopurinol [5mg/kg] once a day for 14 days. Experimentally, hyperuricemia in rats was induced by intraperitoneal injection of potassium oxonate [250mg/kg]. Allium cepa L. and quercetin treatments for 14 days significantly reduced [p=0.000] the serum uric acid levels of hyperuricemic rats in a time-dependent manner. All treatments significantly inhibited hepatic xanthine oxidase/xanthine dehydrogenase activity. Allium cepa L. and quercetin treatments led also to a significant improvement in biomarkers of oxidative stress in hyperuricemic rats [p=0.000]. Although the hypouricemic effect of allopurinol was much higher than that of Allium cepa L. and quercetin, it could not significantly change oxidative stress biomarkers. These results may be responsible partly for the beneficial effects of Allium cepa L. and its major flavonoid on hyperuricemia and oxidative stress