Astragalus polysaccharide improves muscle atrophy from dexamethasone- and peroxide-induced injury in vitro

Int J Biol Macromol. 2013 Oct;61:7-16. doi: 10.1016/j.ijbiomac.2013.06.027. Epub 2013 Jun 29.

Abstract

Astragalus polysaccharide (APS) is an important bioactive component of Astragalus membranaceus Bunge (Leguminosae) that has been used in traditional Chinese medicine for treating muscle wasting, a serious complication with complex mechanism manifested as myofibers atrophy and satellite cells apoptosis. In this study, the anti-atrophy and anti-apoptotic activity of Astragalus polysaccharide (APS) was characterized in C2C12 skeletal muscle myotubes and myoblasts. APS inhibited dexamethasone-induced atrophy by restoring phosphorylation of Akt, m-TOR, P70s6k, rpS6 and FoxO3A/FoxO1. The targets that protected C2C12 myoblasts from damage by H2O2 were promoting cells proliferation and inhibiting cells apoptosis. The protective mechanisms involved mitochondrial pathway and death receptor pathway. Moreover, Antioxidant effect of APS was also detected in this work. Our findings suggested that APS could be explored as a protective and perhaps as a therapeutic agent in the management of muscle wasting.

Keywords: Apoptosis; Astragalus polysaccharide; Atrophy; Myoblast; Myotubes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Apoptosis Regulatory Proteins / metabolism
  • Astragalus Plant / chemistry*
  • Cell Death / drug effects
  • Cell Line
  • Cell Proliferation / drug effects
  • Dexamethasone / adverse effects
  • Enzyme Activation / drug effects
  • Hydrogen Peroxide / adverse effects
  • Mice
  • Muscle Fibers, Skeletal / drug effects
  • Muscle Fibers, Skeletal / metabolism
  • Muscle Fibers, Skeletal / pathology
  • Muscular Atrophy / chemically induced
  • Muscular Atrophy / metabolism*
  • Myoblasts, Skeletal / drug effects
  • Myoblasts, Skeletal / metabolism
  • Myoblasts, Skeletal / pathology
  • Polysaccharides / pharmacology*
  • Protein Tyrosine Phosphatase, Non-Receptor Type 1 / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • Reactive Oxygen Species / metabolism
  • Signal Transduction / drug effects
  • TOR Serine-Threonine Kinases / metabolism

Substances

  • Apoptosis Regulatory Proteins
  • Polysaccharides
  • Reactive Oxygen Species
  • Dexamethasone
  • Hydrogen Peroxide
  • TOR Serine-Threonine Kinases
  • Proto-Oncogene Proteins c-akt
  • Protein Tyrosine Phosphatase, Non-Receptor Type 1