PubMed · 2000 · 25 citations · 0 references
Life SciencesCell BiologyMolecular BiologyApoptosisMitochondrial BiologyRadiobiologyBiological Effects Of RadiationCellular Radiation ResponseDna Damage-induced ApoptosisMitochondrial DysfunctionRadiation-induced Cell DeathApoptosis After IrradiationCell Cycle AnalysisCell Survival CurvesCell Viability AssaysIonizing IrradiationIrradiation EffectsRadiation Sensitivity AssaysRadiation-induced Apoptosis
BACKGROUND: We aimed to assess the role of mitochondrial DNA (mtDNA) in ionizing irradiation. MATERIAL AND METHODS: We examined three human fibroblast cell lines either lacking mtDNA (rho 0 cell), carrying mutant mtDNA (syn cell) or normal mtDNA (rho + cell). Cell survival curves were generated with colony formation and dye exclusion tests. Cell cycle analysis and apoptosis assay were performed by flow cytometry. RESULTS: The rho 0 cell line showed a stronger resistance to irradiation than the other two cell lines when assessed by the colony formation assay. In the dye exclusion test, the rho 0 cells revealed a superior cell viability among the cell lines after 5 and 8 Gy irradiation. The rho 0 cells underwent apoptosis at lower rates than the other two cell lines after 2, 5 and 8 Gy irradiation, and showed no alterations in the cell cycle distribution among them. CONCLUSION: mtDNA plays an important role in radiation sensitivity and induction of apoptosis.