title: mTORC1 is involved in the regulation of branched-chain amino acid catabolism in mouse heart.
abstract: The branched-chain α-ketoacid dehydrogenase (BCKDH) complex regulates branched-chain amino acid (BCAA) catabolism by controlling the second step of this catabolic pathway. In the present study, we examined the in vivo effects of treatment with an mTORC1 inhibitor, rapamycin, on cardiac BCKDH complex activity in mice. Oral administration of leucine in control mice significantly activated the cardiac BCKDH complex with an increase in cardiac concentrations of leucine and α-ketoisocaproate. However, rapamycin treatment significantly suppressed the leucine-induced activation of the complex despite similar increases in cardiac leucine and α-ketoisocaproate levels. Rapamycin treatment fully inhibited mTORC1 activity, measured by the phosphorylation state of ribosomal protein S6 kinase 1. These results suggest that mTORC1 is involved in the regulation of cardiac BCAA catabolism.
authors.affiliation: Laboratory of Nutritional Biochemistry Department of Applied Molecular Biosciences Graduate School of Bioagricultural Sciences Nagoya University Nagoya, Japan.
authors.forename: Hongmin
authors.initials: H
authors.lastname: Zhen
authors.affiliation: Laboratory of Nutritional Biochemistry Department of Applied Molecular Biosciences Graduate School of Bioagricultural Sciences Nagoya University Nagoya, Japan.
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Kitaura
authors.affiliation: Laboratory of Nutritional Biochemistry Department of Applied Molecular Biosciences Graduate School of Bioagricultural Sciences Nagoya University Nagoya, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kadota
authors.affiliation: Laboratory of Nutritional Biochemistry Department of Applied Molecular Biosciences Graduate School of Bioagricultural Sciences Nagoya University Nagoya, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Ishikawa
authors.affiliation: Laboratory of Nutritional Biochemistry Department of Applied Molecular Biosciences Graduate School of Bioagricultural Sciences Nagoya University Nagoya, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kondo
authors.affiliation: Laboratory of Nutritional Biochemistry Department of Applied Molecular Biosciences Graduate School of Bioagricultural Sciences Nagoya University Nagoya, Japan.
authors.forename: Minjun
authors.initials: M
authors.lastname: Xu
authors.affiliation: Laboratory of Nutritional Biochemistry Department of Applied Molecular Biosciences Graduate School of Bioagricultural Sciences Nagoya University Nagoya, Japan.
authors.forename: Yukako
authors.initials: Y
authors.lastname: Morishita
authors.affiliation: Laboratory of Nutritional Biochemistry Department of Applied Molecular Biosciences Graduate School of Bioagricultural Sciences Nagoya University Nagoya, Japan.
authors.forename: Miki
authors.initials: M
authors.lastname: Ota
authors.affiliation: Laboratory of Biomacromolecules Department of Applied Molecular Biosciences Graduate School of Bioagricultural Sciences Nagoya University Nagoya, Japan.
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Ito
authors.affiliation: Laboratory of Nutritional Biochemistry Department of Applied Molecular Biosciences Graduate School of Bioagricultural Sciences Nagoya University Nagoya, Japan.
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Shimomura
keywords: branched‐chain amino acid; branched‐chain α‐ketoacid dehydrogenase complex; leucine; mTORC1