title: The effect of taurine and β-alanine supplementation on taurine transporter protein and fatigue resistance in skeletal muscle from mdx mice.
abstract: This study investigated the effect of taurine and β-alanine supplementation on muscle function and muscle taurine transporter (TauT) protein expression in mdx mice. Wild-type (WT) and mdx mice (5 months) were supplemented with taurine or β-alanine for 4 weeks, after which in vitro contractile properties, fatigue resistance and force recovery, and the expression of the TauT protein and proteins involved in excitation-contraction (E-C) coupling were examined in fast-twitch muscle. There was no difference in basal TauT protein expression or basal taurine content between mdx than WT muscle. Supplementation with taurine and β-alanine increased and reduced taurine content, respectively, in muscle from WT and mdx mice but had no effect of TauT protein. Taurine supplementation reduced body and muscle mass, and enhanced fatigue resistance and force recovery in mdx muscle. β-Alanine supplementation enhanced fatigue resistance in WT and mdx muscle. There was no difference in the basal expression of key E-C coupling proteins [ryanodine receptor 1 (RyR1), dihydropyridine receptor (DHPR), sarco(endo)plasmic reticulum Ca2+-ATPase 1 (SERCA1) or calsequestrin 1 (CSQ1)] between WT and mdx mice, and the expression of these proteins was not altered by taurine or β-alanine supplementation. These findings suggest that TauT protein expression is relatively insensitive to changes in muscle taurine content in WT and mdx mice, and that taurine and β-alanine supplementation may be viable therapeutic strategies to improve fatigue resistance of dystrophic skeletal muscle.
authors.affiliation: Department of Physiology, Anatomy and Microbiology, School of Life Sciences, La Trobe University, Melbourne, VIC, 3086, Australia. deanna.horvath@latrobe.edu.au.
authors.forename: Deanna M
authors.initials: DM
authors.lastname: Horvath
authors.affiliation: Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia.
authors.forename: Robyn M
authors.initials: RM
authors.lastname: Murphy
authors.affiliation: Department of Physiology, Anatomy and Microbiology, School of Life Sciences, La Trobe University, Melbourne, VIC, 3086, Australia.
authors.forename: Janelle P
authors.initials: JP
authors.lastname: Mollica
authors.affiliation: Centre for Chronic Disease Prevention and Management, Victoria University, Melbourne, Australia.|Institute of Sport, Exercise and Active Living, Victoria University, Melbourne, Australia.|Australian Institute for Musculoskeletal Science, Western Health, Melbourne, VIC, Australia.
authors.forename: Alan
authors.initials: A
authors.lastname: Hayes
authors.affiliation: Centre for Chronic Disease Prevention and Management, Victoria University, Melbourne, Australia.|Institute of Sport, Exercise and Active Living, Victoria University, Melbourne, Australia.
authors.forename: Craig A
authors.initials: CA
authors.lastname: Goodman
mesh_terms: D000818:Animals; D005221:Fatigue / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects*; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D026901:Membrane Transport Proteins / Q000096:biosynthesis*; D051379:Mice; D018101:Mice, Inbred mdx; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000473:pathology; D009137:Muscular Dystrophy, Animal / Q000378:metabolism / Q000473:pathology; D013654:Taurine / Q000494:pharmacology*; D015091:beta-Alanine / Q000494:pharmacology*; D000099247:Taurine Transporters
chemical_list: D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D013654:Taurine; D015091:beta-Alanine; D000099247:Taurine Transporters
keywords: Duchene muscular dystrophy; Excitation–contraction coupling; Muscle fatigue; Skeletal muscle; Taurine supplementation