Mitochondrial Transfer from Wharton’s Jelly Mesenchymal Stem Cell to MERRF Cybrid Reduces Oxidative Stress and Improves Mitochondrial Bioenergetics

Figure 3

WJMSC transferred mitochondria to MERRF cybrid through a protruded tubular structure. (a) Schematic of contact coculture in which WJMSC and cybrid cell were transfected, respectively, with Cox4-DsRed and Su9-EGFP to tracking mitochondria. (b) After 24 h of coculture, images were photographed under fluorescent microscope. Scale bar, 5 μm. (b′) Types of transferred mitochondria. MERRF cybrids with transferred mitochondria from WJMSC were categorized into concentrated or mixed type. Histogram data are from three experiments, with 50–100 cells counted per experiment. (c) Mitochondria of WJMSC was transferred via a protruded tubular structure to MERRF cybrid. Arrow indicates intercellular mitochondrial fusion with yellow signal. Rectangular dotted line was enlarged in (c′). (c′) Arrowheads indicate that mitochondria of WJMSC was transported along a protruded tubular structure. (d and e) Dot plot of both channels of FACS revealed percentage of mitochondrial transfer in the upper-right quadrant. (f) Schematic of separate coculture in which a 3 μm pore membrane divides Cox4-DsRed-expressing WJMSC from cybrid. (g) Mitochondria from WJMSC transmitted through membrane pore was examined under fluorescence microscope after the upper chamber was offloaded. Percentage of fluorescence-positive events were counted from 25 to 40 view fields of at least three experiments. CT, control cybrid; CT^RO, control cybrid pretreated with 500 nM rotenone for 24 h; WJ, WJMSC; MF, MERRF cybrid; MF+WJ, MERRF cybrid-plus-WJMSC; WJ^CB, WJMSC pretreated with 350 nM cytochalasin B for 24 h.

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