5-Azacytidine and Resveratrol Enhance Chondrogenic Differentiation of Metabolic Syndrome-Derived Mesenchymal Stem Cells by Modulating Autophagy

Figure 9

Evaluation of mitophagy during chondrogenic differentiation. Prior to experiments, cells were pretreated with AZA/RES for 24 hours, then the experimental medium was replaced by osteogenic differentiation medium. Cells were cultured in that medium for five days and after were subjected to further analysis. Using immunofluorescence, localization of PINK and PARKIN in chondrogenic nodules was visualized with confocal microscope (a). Nuclei of cells were stained with DAPI (a). PINK and PARKIN fluorescence was diminished in EMS cells as well as size of nodules. Furthermore, formation of mitophagosomes and lysosomes was established with TEM (b). Mitochondria in the EMS cells were packed into mitophagosomes while mitochondria from the EMS EXP groups did not display morphology abnormalities. Interestingly, mitochondria in the CTRL group frequently fused with lysosomes. Expression of PINK (c) and PARKIN (d) was investigated with RT-PCR. Abbreviations: LYS: lysosome, Mt: mitochondrion, MP: mitophagosome, ER: endoplasmic reticulum. Results expressed as . Statistical significance indicated as an asterisk () when comparing the result to ASC_EMS and as a number sign (#) when comparing to ASC_CTRL. ^##, ^### and .

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