The effect of ginger on diabetic nephropathy, plasma antioxidant capacity and lipid peroxidation in rats

Oxidative stress is a major factor in the pathogenesis of diabetic complications. We studied the effects of ginger powder on nephropathy induced by diabetes, and measured changes in plasma antioxidant capacity and lipid peroxidation. Wistar rats weighing 250 20 g were treated with STZ 60 mg/kg. Rats were divided into 3 groups (n = 8) of non-diabetic, diabetic non-treated and diabetic treated with ginger powder. The diabetic treated with ginger group received ginger at 5% of their consumed food daily. After 8 weeks the rats were anaesthetized with 10% chloral hydrate. Blood samples were collected from the heart of each rat and kidneys were removed and kept in 10% formalin buffer. Plasma and red blood cells were separated. Plasma antioxidant capacity by the FRAP method and red blood cells malondialdehyde (MDA) as an indictor of lipids peroxidation, were measured. After sectioning and staining of renal samples, they were studied for focal cell proliferation and glomerular and tubular structural changes. The MDA levels in diabetic rats treated with ginger were significantly lower than in the other groups (P < 0.01). Plasma antioxidant capacity in ginger treated rats were higher than in the first two groups. Diabetes induced nephropathies were also lower in the ginger treated group. This study demonstrates that ginger causes a decrease in lipid peroxidation, an increase of plasma antioxidant capacity and a reduction in renal nephropathy. (c) 2006 Elsevier Ltd. All rights reserved.