title: Myostatin dysfunction impairs force generation in extensor digitorum longus muscle and increases exercise-induced protein efflux from extensor digitorum longus and soleus muscles.
abstract: Myostatin dysfunction promotes muscle hypertrophy, which can complicate assessment of muscle properties. We examined force generating capacity and creatine kinase (CK) efflux from skeletal muscles of young mice before they reach adult body and muscle size. Isolated soleus (SOL) and extensor digitorum longus (EDL) muscles of Berlin high (BEH) mice with dysfunctional myostatin, i.e., homozygous for inactivating myostatin mutation, and with a wild-type myostatin (BEH+/+) were studied. The muscles of BEH mice showed faster (P < 0.01) twitch and tetanus contraction times compared with BEH+/+ mice, but only EDL displayed lower (P < 0.05) specific force. SOL and EDL of age-matched but not younger BEH mice showed greater exercise-induced CK efflux compared with BEH+/+ mice. In summary, myostatin dysfunction leads to impairment in muscle force generating capacity in EDL and increases susceptibility of SOL and EDL to protein loss after exercise.
authors.affiliation: a Institute of Sports Sciences and Innovation, Lithuanian Sports University, Sporto 6, LT-44221, Kaunas, Lithuania.
authors.forename: Juozas
authors.initials: J
authors.lastname: Baltusnikas
authors.affiliation: a Institute of Sports Sciences and Innovation, Lithuanian Sports University, Sporto 6, LT-44221, Kaunas, Lithuania.
authors.forename: Audrius
authors.initials: A
authors.lastname: Kilikevicius
authors.affiliation: a Institute of Sports Sciences and Innovation, Lithuanian Sports University, Sporto 6, LT-44221, Kaunas, Lithuania.
authors.forename: Tomas
authors.initials: T
authors.lastname: Venckunas
authors.affiliation: a Institute of Sports Sciences and Innovation, Lithuanian Sports University, Sporto 6, LT-44221, Kaunas, Lithuania.
authors.forename: Andrej
authors.initials: A
authors.lastname: Fokin
authors.affiliation: b Scotland's Rural College (SRUC), Edinburgh, UK.
authors.forename: Lutz
authors.initials: L
authors.lastname: Bünger
authors.affiliation: c School of Medical Sciences, College of Life Sciences and Medicine, University of Aberdeen, Aberdeen, Scotland, UK.
authors.forename: Arimantas
authors.initials: A
authors.lastname: Lionikas
authors.affiliation: a Institute of Sports Sciences and Innovation, Lithuanian Sports University, Sporto 6, LT-44221, Kaunas, Lithuania.|c School of Medical Sciences, College of Life Sciences and Medicine, University of Aberdeen, Aberdeen, Scotland, UK.
authors.forename: Aivaras
authors.initials: A
authors.lastname: Ratkevicius
mesh_terms: D000818:Animals; D003402:Creatine Kinase / Q000378:metabolism*; D005260:Female; D051379:Mice; D009043:Motor Activity / Q000502:physiology*; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000378:metabolism*; D055435:Myostatin / Q000172:deficiency*
chemical_list: D055435:Myostatin; D003402:Creatine Kinase
keywords: contraction avec étirement; force musculaire; lengthening contractions; lésion musculaire; muscle damage; muscle force; myostatin; myostatine