Effects of Leucine and Isoleucine on Glucose Metabolism

Abstract

The branched chain amino acids (BCAAs) have recently been recognized as having functions other than simple nutrition. The signaling action of leucine in protein synthesis has been well studied, but the pharmacological effects of isoleucine and valine have not been clarified. It has recently been reported that, among the BCAAs, leucine and isoleucine act as signals in glucose metabolism. We revealed that isoleucine stimulates both glucose uptake in the muscle and whole body glucose oxidation, in addition to depressing gluconeogenesis in the liver, thereby leading to a hypoglycemic effect in rats. The major focus of this chapter is on the role of BCAAs in regulating glucose metabolism.