title: Potential involvement of dietary advanced glycation end products in impairment of skeletal muscle growth and muscle contractile function in mice.
abstract: Diets enriched with advanced glycation end products (AGE) have recently been related to muscle dysfunction processes. However, it remains unclear whether long-term exposure to an AGE-enriched diet impacts physiological characteristics of skeletal muscles. Therefore, we explored the differences in skeletal muscle mass, contractile function and molecular responses between mice receiving a diet high in AGE (H-AGE) and low in AGE (L-AGE) for 16 weeks. There were no significant differences between L-AGE and H-AGE mice with regard to body weight, food intake or epididymal fat pad weight. However, extensor digitorum longus (EDL) and plantaris (PLA) muscle weights in H-AGE mice were lower compared with L-AGE mice. Higher levels of N ε -(carboxymethyl)-l-lysine, a marker for AGE, in EDL muscles of H-AGE mice were observed compared with L-AGE mice. H-AGE mice showed lower muscle strength and endurance in vivo and lower muscle force production of PLA muscle in vitro. mRNA expression levels of myogenic factors including myogenic factor 5 and myogenic differentiation in EDL muscle were lower in H-AGE mice compared with L-AGE mice. The phosphorylation status of 70-kDa ribosomal protein S6 kinase Thr389, an indicator of protein synthesis signalling, was lower in EDL muscle of H-AGE mice than that of L-AGE mice. These findings suggest that long-term exposure to an AGE-enriched diet impairs skeletal muscle growth and muscle contractile function, and that these muscle dysfunctions may be attributed to the inhibition of myogenic potential and protein synthesis.
authors.affiliation: 1Laboratory of Sports and Exercise Medicine,Graduate School of Human and Environmental Studies,Kyoto University,Kyoto,606-8501,Japan.
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Egawa
authors.affiliation: 1Laboratory of Sports and Exercise Medicine,Graduate School of Human and Environmental Studies,Kyoto University,Kyoto,606-8501,Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tsuda
authors.affiliation: 1Laboratory of Sports and Exercise Medicine,Graduate School of Human and Environmental Studies,Kyoto University,Kyoto,606-8501,Japan.
authors.forename: Ayumi
authors.initials: A
authors.lastname: Goto
authors.affiliation: 3Laboratory of Physiology,School of Health Sciences,Toyohashi Sozo University,Toyohashi,Aichi,440-8511,Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Ohno
authors.affiliation: 3Laboratory of Physiology,School of Health Sciences,Toyohashi Sozo University,Toyohashi,Aichi,440-8511,Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Yokoyama
authors.affiliation: 2Department of Physiology,Graduate School of Health Sciences,Toyohashi Sozo University,Toyohashi,Aichi,440-8511,Japan.
authors.forename: Katsumasa
authors.initials: K
authors.lastname: Goto
authors.affiliation: 1Laboratory of Sports and Exercise Medicine,Graduate School of Human and Environmental Studies,Kyoto University,Kyoto,606-8501,Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Hayashi
mesh_terms: D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D004032:Diet; D005786:Gene Expression Regulation / Q000187:drug effects; D017127:Glycation End Products, Advanced / Q000008:administration & dosage* / Q000633:toxicity; D008239:Lysine / Q000031:analogs & derivatives / Q000378:metabolism; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009119:Muscle Contraction / Q000187:drug effects*; D018482:Muscle, Skeletal / Q000254:growth & development*; D018006:Myogenic Regulatory Factors / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D017127:Glycation End Products, Advanced; D018006:Myogenic Regulatory Factors; D012333:RNA, Messenger; C048496:N(6)-carboxymethyllysine; D008239:Lysine
keywords:  AGE advanced glycation end products;  CML 
                    N
                    ∑-(carboxymethyl)-L-lysine;  EDL extensor digitorum longus;  H-AGE high in AGE;  L-AGE low in AGE;  LC3 microtubule-associated protein light-chain 3;  MHC myosin heavy chain;  Myf5 myogenic factor 5;  MyoD myogenic differentiation;  PLA 
                    plantaris
                 ;  Pax7 paired box 7;  SOL 
                    soleus
                 ;  mTOR mammalian target of rapamycin;  p70S6K 70-kDa ribosomal protein S6 kinase; Muscle fatigue resistance; Muscle force production; Muscle strength; Myogenesis; Protein synthesis