TY - JOUR T1 - Therapeutic Potential of (-)-Epigallocatechin 3-<em>O</em>-Gallate on Renal Damage in Diabetic Nephropathy Model Rats JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 228 LP - 236 DO - 10.1124/jpet.106.107029 VL - 319 IS - 1 AU - Noriko Yamabe AU - Takako Yokozawa AU - Takeshi Oya AU - Mujo Kim Y1 - 2006/10/01 UR - http://jpet.aspetjournals.org/content/319/1/228.abstract N2 - Previous investigations have demonstrated that green tea polyphenols and partially hydrolyzed guar gum as dietary fiber have antioxidative and hypolipidemic activity, respectively, supporting their reduction of risk factors in the course of diabetic nephropathy via a hypoglycemic effect and ameliorating the decline of renal function through their combined administration to rats with subtotal nephrectomy plus streptozotocin (STZ) injection. As a further study, we examined whether (-)-epigallocatechin 3-O-gallate (EGCg), the main polyphenolic compound, could ameliorate the development of diabetic nephropathy. Rats with subtotal nephrectomy plus STZ injection were orally administrated EGCg at doses of 25, 50, and 100 mg/kg body weight/day. After a 50-day administration period, EGCg-treated groups showed suppressed hyperglycemia, proteinuria, and lipid peroxidation, although there were only weak effects on the levels of serum creatinine and glycosylated protein. Furthermore, EGCg reduced renal advanced glycation end-product accumulation and its related protein expression in the kidney cortex as well as associated pathological conditions. These results suggest that EGCg ameliorates glucose toxicity and renal injury, thus alleviating renal damage caused by abnormal glucose metabolism-associated oxidative stress involved in renal lesions of diabetic nephropathy. The American Society for Pharmacology and Experimental Therapeutics ER -