L-Leucine-d₁₀is intended for use as an internal standard for the quantification of L-leucine by GC- or LC-MS. L-Leucine is an essential amino acid.¹It increases basal insulin secretion and decreases glucose-induced insulin release in INS-1E rat insulinoma cells when used at concentrations of 1, 5, and 10 mM.²L-Leucine (1, 5, and 10 mM) decreases triglyceride levels and increases cholesterol accumulation in INS-1E cells. It stimulates skeletal muscle protein synthesis in exercised rats, as well as in food-deprived rats in an mTOR-dependent manner.^3,4Formulations containing L-leucine have been used as dietary supplements.

1.Duan, Y., Li, F., Li, Y., et al.The role of leucine and its metabolites in protein and energy metabolismAmino Acids48(1)41-51(2016) 2.Liu, Z., Jeppesen, P.B., Gregersen, S., et al.Chronic exposure to leucine in vitro induces β-cell dysfunction in INS-1E cells and mouse isletsJ. Endocrinol.215(1)79-88(2012) 3.Anthony, J.C., Yoshizawa, F., Anthony, T.G., et al.Leucine stimulates translation initiation in skeletal muscle of postabsorptive rats via a rapamycin-sensitive pathwayJ. Nutr.130(10)2413-2419(2000) 4.Anthony, J.C., Anthony, T.G., and Layman, D.K.Leucine supplementation enhances skeletal muscle recovery in rats following exerciseJ. Nutr.129(6)1102-1106(1999)