Feeding of buckwheat protein extract reduces hepatic triglyceride concentration, adipose tissue weight, and hepatic lipogenesis in rats

Abstract

The objective of this study was to examine effects of feeding buchwheat protein extract (BWPE) on hepatic and plasma lipids, fat pad weights and activities of enzymes relating to lipid metabolism in tissues of rats. Rats were fed a semipurified diet containing either buckwheat protein extract or casein for 3 weeks. Food consumption and growth rate were unaffected by dietary treatment. Hepatic triglyceride concentration and the weights of epididymal and perirenal fat pad were significantly lower in rats fed BWPE compared with those fed casein diet. BWPE feeding caused lower activities of hepatic glucose-6-phosphate dehydrogenase and fatty acid synthase, but did not affect the activity of hepatic carnitine palmitoyltransferase I. In addition, BWPE caused increases in fecal fat and nitrogen. These results demonstrated that feeding BWPE causes reductions in hepatic triglyceride concentration and fat pad weights, and suggested that these reductions might be ascribed to lower activities of hepatic lipogenic enzymes and to lower digestibility of fat and protein. Furthermore, analysis of plasma free amino acids showed marked increases of glycine and arginine in rats fed BWPE compared with rats fed casein, raising the possibility that these alterations in plasma amino acids lead to reduction in body fat.