title: Branched-chain amino acid-rich diet improves skeletal muscle wasting caused by cigarette smoke in rats.
abstract: Cigarette smoke induces skeletal muscle wasting by a mechanism not yet fully elucidated. Branched-chain amino acids (BCAA) in the skeletal muscles are useful energy sources during exercise or systemic stresses. We investigated the relationship between skeletal muscle wasting caused by cigarette smoke and changes in BCAA levels in the plasma and skeletal muscles of rats. Furthermore, the effects of BCAA-rich diet on muscle wasting caused by cigarette smoke were also investigated. Wistar Kyoto (WKY) rats that were fed with a control or a BCAA-rich diet were exposed to cigarette smoke for four weeks. After the exposure, the skeletal muscle weight and BCAA levels in plasma and the skeletal muscles were measured. Cigarette smoke significantly decreased the skeletal muscle weight and BCAA levels in both plasma and skeletal muscles, while a BCAA-rich diet increased the skeletal muscle weight and BCAA levels in both plasma and skeletal muscles that had decreased by cigarette smoke exposure. In conclusion, skeletal muscle wasting caused by cigarette smoke was related to the decrease of BCAA levels in the skeletal muscles, while a BCAA-rich diet may improve cases of cigarette smoke-induced skeletal muscle wasting.
authors.affiliation: Second Department of Internal Medicine, Nara Medical University.
authors.forename: Koichi
authors.initials: K
authors.lastname: Tomoda
authors.forename: Kaoru
authors.initials: K
authors.lastname: Kubo
authors.forename: Kazuo
authors.initials: K
authors.lastname: Hino
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Kondoh
authors.forename: Yasue
authors.initials: Y
authors.lastname: Nishii
authors.forename: Noriko
authors.initials: N
authors.lastname: Koyama
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Masanori
authors.initials: M
authors.lastname: Yoshikawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kimura
mesh_terms: D000597:Amino Acids, Branched-Chain / Q000008:administration & dosage* / Q000097:blood / Q000378:metabolism* / Q000494:pharmacology; D000818:Animals; D004032:Diet; D004734:Energy Metabolism; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000473:pathology; D009133:Muscular Atrophy / Q000178:diet therapy* / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D011921:Rats, Inbred WKY; D012907:Smoking / Q000009:adverse effects*
chemical_list: D000597:Amino Acids, Branched-Chain