Elevated levels of active matrix metalloproteinase-9 cause hypertrophy in skeletal muscle of normal and dystrophin-deficient mdx mice.

ABSTRACT: Matrix metalloproteinases (MMPs) are a group of extracellular proteases involved in tissue remodeling in several physiological and pathophysiological conditions. While increased expression of MMPs (especially MMP-9) has been observed in skeletal muscle in numerous conditions, their physiological significance remains less-well understood. By generating novel skeletal muscle-specific transgenic (Tg) mice expressing constitutively active mutant of MMP-9 (i.e. MMP-9G100L), in this study, we have investigated the effects of elevated levels of MMP-9 on skeletal muscle structure and function in vivo. Tg expression of enzymatically active MMP-9 protein significantly increased skeletal muscle fiber cross-section area, levels of contractile proteins and force production in isometric contractions. MM

SUBMITTER: Dahiya S 

PROVIDER: S-EPMC3196885 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature