The effects of grape seed on apoptosis-related gene expression and oxidative stress in streptozotocin-induced diabetic rats.

Diabetic nephropathy is the most common cause of end-stage renal disease. Emerging evidences indicate that many mechanistic pathways including apoptosis play an important role in the pathogenesis and progression of macrovascular and microvascular complications of diabetes mellitus. The aim of the present study is to show the effects of grape seed extract (GSE) on oxidative stress and apoptosis in the kidney of streptozotocin-induced diabetic rats. The study included control group, diabetic group without treatment and diabetic group treated with GSE (n=7) group. GSE was given orally (100 mg/kg/day) for six weeks. Following parameters were evaluated; oxidative stress index, caspase 1, IL1-alpha, caspase 2, IL1-beta, BCL2-associated agonist of cell death (BAD), X-linked inhibitor of apoptosis (XIAP), DNA fragmentation factor, alpha subunit and beta bubunit (DFFA, DFFB), BH3 interacting domain death agonist (BID), caspase 6, Bcl2-like 1 (BCL-XL), caspase 8, tumor necrosis factor receptor superfamily, member 1 b (TNFRSF1B) and IAP-binding mitochondrial protein (DIABLO). Oxidative stress index levels were significantly increased in the kidney of diabetic group without treatment compared to control group, and decreased in diabetic+GSE group compared to diabetic group without treatment. In the kidney of diabetic group without treatment, caspase 1, IL-1 alpha, BAD, DFFA, DFFB and caspase-6 gene expressions were significantly higher compared to control group. In diabetic+GSE group caspase 1, caspase 2, XIAP, DFFA, BID, BCL-XL and TNFRSF1B genes were significantly decreased compared to control group. Grape seed reduces oxidative stress and apoptosis gene expression suggesting the protective effect on diabetic nephropathy.