title: Nutritional and regulatory roles of leucine in muscle growth and fat reduction.
abstract: The metabolic roles for L-leucine, an essential branched-chain amino acid (BCAA), go far beyond serving exclusively as a building block for de novo protein synthesis. Growing evidence shows that leucine regulates protein and lipid metabolism in animals. Specifically, leucine activates the mammalian target of rapamycin (mTOR) signaling pathway, including the 70 kDa ribosomal protein S6 kinase 1 (S6K1) and eukaryotic initiation factor (eIF) 4E-binding protein 1 (4EBP1) to stimulate protein synthesis in skeletal muscle and adipose tissue and to promote mitochondrial biogenesis, resulting in enhanced cellular respiration and energy partitioning. Activation of cellular energy metabolism favors fatty acid oxidation to CO2 and water in adipocytes, lean tissue gain in young animals, and alleviation of muscle protein loss in aging adults, lactating mammals, and food-deprived subjects. As a functional amino acid, leucine holds great promise to enhance the growth, efficiency of food utilization, and health of animals and humans.
authors.affiliation: Chinese Academy of Science, Institute of Subtropical Agriculture, Research Center for Healthy Breeding Livestock and Poultry, Hunan Engineering and Research Center for Animal and Poultry Science, Key Laboratory of Agroecology in Subtropical Region, Scient.
authors.forename: Yehui
authors.initials: Y
authors.lastname: Duan
authors.affiliation: Chinese Academy of Science, Institute of Subtropical Agriculture, Research Center for Healthy Breeding Livestock and Poultry, Hunan Engineering and Research Center for Animal and Poultry Science, Key Laboratory of Agroecology in Subtropical Region, Scient.
authors.forename: Fengna
authors.initials: F
authors.lastname: Li
authors.affiliation: Chinese Academy of Science, Institute of Subtropical Agriculture, Research Center for Healthy Breeding Livestock and Poultry, Hunan Engineering and Research Center for Animal and Poultry Science, Key Laboratory of Agroecology in Subtropical Region, Scient.
authors.forename: Hongnan
authors.initials: H
authors.lastname: Liu
authors.affiliation: Chinese Academy of Science, Institute of Subtropical Agriculture, Research Center for Healthy Breeding Livestock and Poultry, Hunan Engineering and Research Center for Animal and Poultry Science, Key Laboratory of Agroecology in Subtropical Region, Scient.
authors.forename: Yinghui
authors.initials: Y
authors.lastname: Li
authors.affiliation: Chinese Academy of Science, Institute of Subtropical Agriculture, Research Center for Healthy Breeding Livestock and Poultry, Hunan Engineering and Research Center for Animal and Poultry Science, Key Laboratory of Agroecology in Subtropical Region, Scient.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Chinese Academy of Science, Institute of Subtropical Agriculture, Research Center for Healthy Breeding Livestock and Poultry, Hunan Engineering and Research Center for Animal and Poultry Science, Key Laboratory of Agroecology in Subtropical Region, Scient.
authors.forename: Xiangfeng
authors.initials: X
authors.lastname: Kong
authors.affiliation: Chinese Academy of Science, Institute of Subtropical Agriculture, Research Center for Healthy Breeding Livestock and Poultry, Hunan Engineering and Research Center for Animal and Poultry Science, Key Laboratory of Agroecology in Subtropical Region, Scient.
authors.forename: Yuzhe
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Chinese Academy of Science, Institute of Subtropical Agriculture, Research Center for Healthy Breeding Livestock and Poultry, Hunan Engineering and Research Center for Animal and Poultry Science, Key Laboratory of Agroecology in Subtropical Region, Scient.
authors.forename: Dun
authors.initials: D
authors.lastname: Deng
authors.affiliation: Chinese Academy of Science, Institute of Subtropical Agriculture, Research Center for Healthy Breeding Livestock and Poultry, Hunan Engineering and Research Center for Animal and Poultry Science, Key Laboratory of Agroecology in Subtropical Region, Scient.
authors.forename: Yulong
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Chinese Academy of Science, Institute of Subtropical Agriculture, Research Center for Healthy Breeding Livestock and Poultry, Hunan Engineering and Research Center for Animal and Poultry Science, Key Laboratory of Agroecology in Subtropical Region, Scient.
authors.forename: Zemeng
authors.initials: Z
authors.lastname: Feng
authors.affiliation: Chinese Academy of Science, Institute of Subtropical Agriculture, Research Center for Healthy Breeding Livestock and Poultry, Hunan Engineering and Research Center for Animal and Poultry Science, Key Laboratory of Agroecology in Subtropical Region, Scient.
authors.forename: Guoyao
authors.initials: G
authors.lastname: Wu
authors.affiliation: Chinese Academy of Science, Institute of Subtropical Agriculture, Research Center for Healthy Breeding Livestock and Poultry, Hunan Engineering and Research Center for Animal and Poultry Science, Key Laboratory of Agroecology in Subtropical Region, Scient.
authors.forename: Yulong
authors.initials: Y
authors.lastname: Yin
mesh_terms: D000273:Adipose Tissue / Q000254:growth & development*; D000818:Animals; D004734:Energy Metabolism; D006801:Humans; D007930:Leucine / Q000502:physiology*; D018482:Muscle, Skeletal / Q000254:growth & development*; D014176:Protein Biosynthesis / Q000502:physiology
chemical_list: D007930:Leucine