Mitochondrial Transfer of Wharton’s Jelly Mesenchymal Stem Cells Eliminates Mutation Burden and Rescues Mitochondrial Bioenergetics in Rotenone-Stressed MELAS Fibroblasts

Figure 1

MELAS patient-derived fibroblasts exhibit mitochondrial dysfunction and increased reactive oxygen species (ROS) expression in a mutation burden-dependent manner. (a) Representative image of the mt.3243A>G mutation burden of each fibroblast clone. The mutation (mt3243A>G) was detected using PCR-RFLP. PCR product containing normal mt.3243A was not digested by Apa I and showed an 1159 bp band. The mt.3243A>G mutation was Apa I-cleaved into 598 and 591 bp band. (b) Relative proportions of the mt.3243A>G mutation burden. (c, d) Mitochondrial and intracellular ROS were detected with MitoSOX™Red and H₂DCFDA, respectively. (e) Representative image of mitochondrion-dependent viability. Glucose-containing culture medium was replaced with glucose-free 10 mM galactose medium at day 0. Cell confluence photographed and viability detected with CCK-8 kit at days 0, 5, and 7. significantly different when compared to all experimental groups. significantly different when compared to the indicated group. Con: control fibroblast from normal human; MF^Ori: original MELAS fibroblast derived from patient; MF^Neg: MELAS fibroblast clone harboring negative mutation burden; MF^Hi: MELAS fibroblast clone harboring high mutation burden; MFI: mean fluorescence intensity.

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