The environmental pollutant cadmium induces homeostasis alteration in muscle cells in vitro

Background Cadmium (Cd) is a heavy metal widely distributed throughout the environment as a result of contamination from a variety of sources. It exerts toxic effects in many tissues but scarce data are present as yet on potential effects on skeletal muscle tissue. Aim To evaluate the potential alteration induced by Cd in skeletal muscle cells. Materials and methods C2C12 skeletal muscle cells were treated with Cd at different times of cellular differentiation and gene expression was evaluated. Results Exposure to Cd decreased significantly p21 mRNA expression and strongly up-regulated cyclin D1 mRNA expression in committed cells and in differentiated myotubes. Moreover, myogenin, fast MyHC-IIb and slow MyHC-I mRNAs expression were also significantly decreased both in committed cells and in myotubes. Moreover, Cd exposure induced a strong increase of Pax3, Pax7 and Myf5 mRNAs expression and stimulated an up-regulation of IL6 and TNF-alpha proinflammatory cytokines. Conclusions These data lead to hypothesize that environmental Cd exposure might trigger an injury-like event in muscle tissue, possibly by an estrogen receptor-mediated mechanism.