Oxidative stress and calcium homeostasis in dystrophic skin fibroblasts

Muscular dystrophy is a genetic disease that affects primarily skeletal mus cle. The dystrophin absence has been related to the degeneration of muscle fibres, Indirect evidences suggest that oxidative stress may play a role in the pathogenesis of the disease, but the significance and precise extent o f this contribution is poorly understood. In this paper,ve show that Becker Muscular Dystrophy (BMD) and Duchenne Muscular Dystrophy (DMD) skin fibrob lasts are more susceptible to H2O2 treatment than are fibroblasts from unaf fected persons. In particular, we found that, in growing DMD skin fibroblas ts, the oxidative treatment resulted in significantly reduced growing capac ity, We also investigated the concentrations of intracellular calcium durin g H2O2 treatment. The intracellular free calcium concentration increased by 22%, 35%, and 40% in unaffected, BMD, and DMD fibroblasts, respectively, H owever, the increase of the intracellular free calcium concentration is not related, as previously hypothesized, to a reduction of acylphosphatase con centrations, which seem to be unaffected by the H2O2 treatment, but rather to reduced enzyme activity.