The Leaf of Diospyros kaki Thumb Ameliorates Renal Oxidative Damage in Mice with Type 2 Diabetes

Diabetic kidney disease is the most common and severe chronic complication of diabetes. The leaf of Diospyros kaki Thumb (persimmon) has been commonly used for herbal tea and medicinal purposes to treat a variety of conditions, including hypertension and atherosclerosis. However, the effect of persimmon leaf on kidney failure has not been investigated. This study aimed to examine the role of persimmon leaf in protecting the diabetes-associated kidney damage in a mouse model of type 2 diabetes. Mice were fed either a normal chow diet with or without powered persimmon leaf (5%, w/w) for 5 weeks. In addition to kidney morphology and blood markers of kidney function, we assessed levels of oxidative stress markers as well as antioxidant enzymes activities and mRNA expression in the kidney. Supplementation of the diet with powered persimmon leaf not only decreased the concentration of blood urea nitrogen in the plasma but also improved glomerular hypertrophy. Furthermore, the persimmon leaf significantly decreased the levels of hydrogen peroxide and lipid peroxide in the kidney. The activities of superoxide dismutase, catalase, and glutathione peroxidase and the mRNA expression of their respective genes were also increased in the kidney of persimmon leaf-supplemented db/db mice. Taken together, these results suggest that supplementation with the persimmon leaf may have protective effects against type 2 diabetes-induced kidney dysfunction and oxidative stress.