Exacerbation of pathology by oxidative stress in respiratory and locomotor muscles with Duchenne muscular dystrophy

J Physiol. 2011 May 1;589(Pt 9):2161-70. doi: 10.1113/jphysiol.2011.207456. Epub 2011 Mar 8.

Abstract

Duchenne muscular dystrophy (DMD) is the most devastating type of muscular dystrophy, leading to progressive weakness of respiratory (e.g. diaphragm) and locomotor muscles (e.g. gastrocnemius). DMD is caused by X-linked defects in the gene that encodes for dystrophin, a key scaffolding protein of the dystroglycan complex (DCG) within the sarcolemmal cytoskeleton. As a result of a compromised dystroglycan complex, mechanical integrity is impaired and important signalling proteins (e.g. nNOS, caveolin-3) and pathways are disrupted. Disruption of the dystroglycan complex leads to high susceptibility to injury with repeated, eccentric contractions as well as inflammation, resulting in significant damage and necrosis. Chronic damage and repair cycling leads to fibrosis and weakness. While the link between inflammation with damage and weakness in the DMD diaphragm is unresolved, elevated oxidative stress may contribute to damage, weakness and possibly fibrosis. While utilization of non-specific antioxidant interventions has yielded inconsistent results, recent data suggest that NAD(P)H oxidase could play a pivotal role in elevating oxidative stress via integrated changes in caveolin-3 and stretch-activated channels (SACs). Oxidative stress may act as an amplifier, exacerbating disruption of the dystroglycan complex, upregulation of the inflammatory transcription factor NF-B, and thus functional impairment of force-generating capacity.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Animals
  • Caveolin 3 / metabolism
  • Dystroglycans / metabolism
  • Humans
  • Inflammation Mediators / metabolism
  • Motor Activity*
  • Muscle Contraction*
  • Muscle Strength*
  • Muscle, Skeletal / metabolism*
  • Muscle, Skeletal / pathology
  • Muscle, Skeletal / physiopathology
  • Muscular Dystrophy, Duchenne / metabolism*
  • Muscular Dystrophy, Duchenne / pathology
  • Muscular Dystrophy, Duchenne / physiopathology
  • NADPH Oxidases / metabolism
  • NF-kappa B / metabolism
  • Oxidative Stress*
  • Reactive Oxygen Species / metabolism*
  • Respiratory Muscles / metabolism*
  • Respiratory Muscles / pathology
  • Respiratory Muscles / physiopathology
  • Signal Transduction
  • TRPC Cation Channels / metabolism

Substances

  • Caveolin 3
  • Inflammation Mediators
  • NF-kappa B
  • Reactive Oxygen Species
  • TRPC Cation Channels
  • transient receptor potential cation channel, subfamily C, member 1
  • Dystroglycans
  • NADPH Oxidases