Figure 2. Impaired mitochondrial functions and accumulation of endogenous ROS in MERRF-specific hiPSCs harboring mtDNA A8344G.

(A) Representative data showing the oxygen consumption rate (OCR) in M1, M2 and M1^Ctrl hiPSC sublines. (B) Quantitative data of basal oxygen consumption, ATP production, maximal respiration and proton leak. Data are the mean ± SEM, n = 3. (C) Intracellular ROS production of hiPSC as indicated by DCFH-dA staining; fluorescence intensity was measured by flow cytometry. The intensity of the M1^ctrl line was defined as 100%. Data are the mean ± SEM, n = 3. (D) qPCR demonstrating the expression level of antioxidant-associated enzymes. Data are the mean ± SEM, n = 3 (E) Western blot indicated the antioxidant enzymes expression. (F) The data represented mean ± SEM of (E), n = 3. (G) Cell proliferation rate of hiPSC sublines. Cell proliferation was determined based on the CCK-8 kit. M1 and M2, MERRF induced pluripotent stem cells. M1^Ctrl, MERRF induced pluripotent stem cells carrying normal mtDNA (A8344G free subline).