Rice bran protein ameliorates diabetes, reduces fatty liver, and has renoprotective effects in Zucker Diabetic Fatty rats
Masatoshi Kubota, Reiko Watanabe, Michihiro Hosojima, Akihiko Saito, Ai Sasou, Takehiro Masumura, Yukikazu Harada, Hiroyuki Hashimoto, S Fujimura, Motoni Kadowaki
Abstract
The beneficial effects of rice bran protein (RBP), which comprises 12.8% of rice bran, have not been fully characterized. Therefore, the effects of RBP on diabetes, fatty liver, and diabetic nephropathy were investigated in Zucker Diabetic Fatty (ZDF) rats. Six-week-old male ZDF rats were fed RBP or casein (C)-based diets for 8 weeks. RBP-fed rats gained significantly more weight, but fat depot was not different from C-fed rats. Hemoglobin A1c and plasma adiponectin levels were significantly improved by consuming RBP rather than C. In RBP-fed rat livers, lipid accumulation was much lower, and the concentrations of metabolites involved in glycolysis, and betaine and carnitine metabolism were significantly higher. In addition, urinary albumin and N-acetyl-β-D-glucosaminidase excretion, and histological damage in the kidney, were significantly lower in RBP-fed rats. In conclusion, an RBP-containing diet ameliorates diabetes, fatty liver, and diabetic nephropathy in rats, compared with a C-based diet.