title: Soluble activin receptor type IIB increases forward pulling tension in the mdx mouse.
abstract: BACKGROUND
  In this study we investigated the action of RAP-031, a soluble activin receptor type IIB (ActRIIB) comprised of a form of the ActRIIB extracellular domain linked to a murine Fc, and the NF-κB inhibitor, ursodeoxycholic acid (UDCA), on the whole body strength of mdx mice.
  
  
  METHODS
  The whole body tension (WBT) method of assessing the forward pulling tension (FPT) exerted by dystrophic (mdx) mice was used.
  
  
  RESULTS
  RAP-031 produced a 41% increase in body mass and a 42.5% increase in FPT without altering the FPT normalized for body mass (WBT). Coadministration of RAP-031 with UDCA produced increases in FPT that were associated with an increase in WBT.
  
  
  CONCLUSIONS
  Myostatin inhibition increases muscle mass without altering the fundamental weakness characteristic of dystrophic muscle. Cotreatment with an NF-κB inhibitor potentiates the effects of myostatin inhibition in improving FPT in mdx mice.
authors.affiliation: Department of Physiology, Kirksville College Osteopathic Medicine, AT Still University, Kirksville, Missouri 63501, USA. ccarlson@atsu.edu
authors.forename: C
authors.initials: C
authors.lastname: George Carlson
authors.forename: Kay
authors.initials: K
authors.lastname: Bruemmer
authors.forename: Jenna
authors.initials: J
authors.lastname: Sesti
authors.forename: Casey
authors.initials: C
authors.lastname: Stefanski
authors.forename: Heather
authors.initials: H
authors.lastname: Curtis
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Ucran
authors.forename: Jennifer
authors.initials: J
authors.lastname: Lachey
authors.forename: Jasbir S
authors.initials: JS
authors.lastname: Seehra
mesh_terms: D030301:Activin Receptors, Type II / Q000494:pharmacology / Q000502:physiology*; D000818:Animals; D005260:Female; D008297:Male; D051379:Mice; D018101:Mice, Inbred mdx; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology; D009129:Muscle Tonus / Q000187:drug effects / Q000502:physiology*; D018482:Muscle, Skeletal / Q000187:drug effects / Q000502:physiology*; D009137:Muscular Dystrophy, Animal / Q000235:genetics / Q000503:physiopathology*; D012995:Solubility
chemical_list: D030301:Activin Receptors, Type II; C425584:activin receptor type II-B