RESUMO
Objective To obtain myoclonic epilepsy with ragged-red fibers (MERRF)-specific cardiomyocytes by the differentiation in vitro of inducing pluripotent stem cells (iPSC) derived from a MERRF patient and evaluate the application of the prepared cardiomyocytes in construction of MERRF syndrome model.Methods The patient-derived iPSCs and H9 embryonic stem (ES) cells,the control cell line,were unidirectionally differentiated into cardiomyocytes n in vitro.The obtained cardiomyocytes were identified and validated by detecting the presence of cardiomyocyte-specific markers using immunofluorescence staining and RT-PCR.The beating frequencies were recorded to compare the functional evaluation for the two groups of cardiomyocyte.Results Both the patient-derived iPSC and H9 ES cells were differentiated into cardiomyocytes successfully.The average beating frequencies of MERRF-induced cardiomyocytes (iCMs) were 13,24,15 and 18 times/min on the day 10,13,15 and 16 during the cell differentiation process.The average beating frequencies of H9-iCMs were 80,96,120 and 120 times/min,respectively.The beating ability of iPSC-differentiated cardiomyocytes was significantly lower than that of corresponding control (all P ＜ 0.05).Conclusion The patient-derived iPSCs may differentiated into cardiomyocytes.Based on the functional evaluation for these cardiomyocytes,the model for MERRF syndrome with mitochondrial mutations was generated and characterized in vitro.