RESUMEN
Cell lines with high passage numbers exhibit alterations in cell morphology and functions. In the present work, C2C12 skeletal muscle cells with either low (<20) or high (>60) passage numbers (identified as l-C2C12 or h-C2C12, respectively) were used to investigate the apoptotic response to H2O2 as a function of culture age h-C2C12. We found that older cultures (h-C2C12 group) were depleted of mitochondrial DNA (mtDNA). When we analyzed the behavior of Bad, Bax, caspase-3 and mitochondrial transmembrane potential, we observed that cells in the h-C2C12 group were resistant to H2O2 induction of apoptosis. We propose serially cultured C2C12 cells as a refractory model to H2O2-induced apoptosis. In addition, the data obtained in this work suggest that mtDNA is required for apoptotic cell death in skeletal muscle C2C12 cells.(AU)
Asunto(s)
Animales , Ratones , Apoptosis/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Mitocondrias/patología , Mioblastos Esqueléticos/patología , Oxidantes/farmacología , Western Blotting , Caspasa 3/metabolismo , Técnicas de Cultivo de Célula , División Celular/efectos de los fármacos , Células Cultivadas , Inmunoprecipitación , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Microscopía Fluorescente , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mioblastos Esqueléticos/efectos de los fármacos , Mioblastos Esqueléticos/metabolismo , Proteína X Asociada a bcl-2/metabolismoRESUMEN
Cell lines with high passage numbers exhibit alterations in cell morphology and functions. In the present work, C2C12 skeletal muscle cells with either low (< 20) or high (> 60) passage numbers (identified as 1-C2C12 or h-C2C12, respectively) were used to investigate the apoptotic response to H2O2 as a function of culture age h-C2C12. We found that older cultures (h-C2C12 group) were depleted of mitochondrial DNA (mtDNA). When we analyzed the behavior of Bad, Bax, caspase-3 and mitochondrial transmembrane potential, we observed that cells in the h-C2C12 group were resistant to H2O2 induction of apoptosis. We propose serially cultured C2Cl2 cells as a refractory model to H2O2-induced apoptosis. In addition, the data obtained in this work suggest that mtDNA is required for apoptotic cell death in skeletal muscle C2C12 cells.