Abstract: Objective　To explore the effect of  mesenchymal stem cells derived exosomes (MSCs-Exo) on peritoneal mesothelial injury induced by high glucose. Methods　MET-5A cells were divided into three groups: normal control group (no treatment), high glucose group (treated with high glucose) and co-culture group (treated with high glucose and MSCs-Exo). High glucose concentration and MSCs-Exo concentration with the best stimulation effect were selected by CCK-8 method. After 24 hours of treatment in each group, the cells and supernatant were collected. The cells proliferation activity was determined by CCK-8, cell apoptosis was tested by flow cytometry, the expression of cytokines IL-6 and TNF-α was detected by qRT-PCR, and the level of IL-6 in culture supernatant was detected by ELISA. Results　The cell viability of high glucose group was significantly lower than that of normal control group (P<0.001), and the apoptosis rate, expression of IL-6 and TNF-α were significantly higher (P<0.001). Compared with the high glucose group, the cell viability of the co-culture group was increased (P<0.001), and the apoptosis rate, IL-6 and TNF-α expression were significantly down-regulated (P<0.05). Conclusion　High glucose has significant pro-apoptotic and pro-inflammatory effects on mesothelial cells. While  MSCs-Exo can promote mesothelial cells proliferation and inhibit the occurrence of apoptosis and the expression of inflammatory factors caused by high glucose.

Key words: Mesenchymal stem cell-derived exosomes, 　High glucose, 　Peritoneal injury, 　Peritonitis