CREATINE SUPPLEMENTATION IMPROVES INTRACELLULAR CA2-MUSCLE CELLS( HANDLING AND SURVIVAL IN MDX SKELETAL)

Dystrophic skeletal muscle cells from Duchenne muscular dystrophy (DMD ) patients and mdx mice exhibit elevated cytosolic Ca2+ concentrations ([Ca2+](c)). Pretreatment of mdx myotubes for 6-12 days with creatine (20 mM) decreased the elevation in [Ca2+](c) induced by either high e xtracellular Ca2+ concentrations or hypo-osmotic stress to control lev els, Ca-45(2+) influx measurements suggest that creatine lowered [Ca2](c), by stimulating sarcoplasmic reticulum Ca2+-ATPase. Creatine pret reatment increased levels of phosphocreatine but not ATP, Furthermore, myotube formation and survival were significantly enhanced by creatin e pretreatment, Therefore, creatine supplementation may be useful for treatment of DMD. (C) 1998 Federation of European Biochemical Societie s.