Abstract: Purpose To investigate the effect of exosomes secreted by human umbilical cord mesenchymal stem cells (HUCMSC-Exo) on aerobic metabolism of cobalt chloride (CoCl2)-induced oxidative damage in human retinal pigment epithelial cell line ARPE-19, and to explore the protective mechanism of HUCMSC-Exo on oxidative damage in ARPE-19 cells. Methods HUCMSC-Exo were extracted and identified; JC-1 flow cytometry was used to detect the effects of exosomes with different concentrations on the apoptosis of oxidatively damaged ARPE-19 cells. The effects of exosomes with different concentrations on the activity of oxidative metabolic enzymes (oxidative respiratory chain complexes I, III, IV, and V) and ATP synthesis in oxidatively damaged ARPE-19 cells were detected by spectrophotometry. Results Under transmission electron microscope, HUCMSC-Exo were round and oval membrane vesicles with diameters of about 40-100 nm. Western blot results showed that HUCMSC-Exo expressed specific marker proteins CD63 and CD9; The proportion of apoptosis in the high-concentration exosomes intervention group was significantly lower than that in the injury non-intervention group; in 50µg/mL and 100µg/mL exosome intervention group, ATP synthesis were significantly different from the control group (P<0.05). The activities of mitochondrial complex I, IV, and V in high concentration exosomes intervention groups were higher than those in other concentration intervention groups. Conclusion HUCMSC-Exo had a certain protective effect on ARPE-19 cells induced by CoCl2 in vitro. The protective mechanism of HUCMSC-Exo on oxidative damage ARPE-19 cells might be through saving its aerobic metabolic function, restoring cell ATP synthesis, and improving the ability of cells to repair damage and deal with the hypoxic environment.

Journal Link: 10.21203/rs.3.rs-1108949/v1 Journal Link: Publisher Website Journal Link: Download PDF Journal Link: Google Scholar