Rice bran phenolic extract supplementation ameliorates impaired lipid metabolism in high-fat-diet fed mice through AMPK activation in liver

Rice bran is a by-product of rice milling, which contains variety of nutrients, and has been reported to possess various activities. Here, we used high fat (HF) diet induced mice to investigate the effects of rice bran phenolic extracts (RBPE) on lipid metabolism. Sixteen-week intake of RBPE (200 mg/kg/d and 400 mg/kg/d) significantly improved the serum lipid profiles of HF diet-fed mice and ameliorated HF diet-induced liver steatosis. Further study showed that RBPE might regulate lipid metabolism through increasing the levels of serum adiponectin, and thereby promoting the activation of 5 ' adenosine monophosphate-activated protein kinase alpha (AMPK alpha) in liver. Taken together, RBPE might regulate lipid metabolism through adiponectin-mediated AMPK activation and the subsequent reduction of lipid biosynthesis together with the increase of fatty acid oxidation in liver. These results provide us new evidence of the health benefits of rice bran.