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

Figure 4

Mitochondrial malfunction of MELAS fibroblasts is improved following mitochondrial transfer. (a) Representative immunoblot image of mitochondrial OXPHOS subunits (nuclear-encoded NDUFA9 and COX4 and mtDNA-encoded COX2). Actin as loading control. (b–d) Quantitative results of protein expression level normalized to actin. (e, f) Mitochondrial and intracellular ROS detected with MitoSOX™ Red and H₂DCFDA, respectively. (g) Mitochondrial membrane potential (ΔΨm) measured by TMRE stain and photographed using a fluorescence microscope. FCCP used to dissipate ΔΨm served as negative control. Scale bar, 100 μm. (h) Mitochondrial membrane potential quantitatively analyzed using flow cytometry. significantly different when compared to the indicated group. WJ: Wharton’s jelly mesenchymal stem cell; Con: control fibroblast from normal human; 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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