Purpose: To investigate whether exosomes derived from human umbilical cord mesenchymal stem cells (hucMSC-derived exosomes) can repair injured endometrial epithelial cells (EECs).
Methods: HucMSC-derived exosomes and mouse primary EECs were isolated and purified. EECs were exposed to oxygen and glucose deprivation for 2 h followed by reoxygenation to mimic injury. After oxygen and glucose deprivation/reoxygenation (OGD/R), hucMSC-derived exosomes were added to the EEC culture medium. After 24 h of co-treatment, cell viability and cell death were tested by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay and lactate dehydrogenase (LDH) assay, respectively. The expression of proinflammatory cytokines was tested by real-time PCR, enzyme-linked immunosorbent assay (ELISA), and Western blot to investigate the potential mechanism.
Results: Compared with the control group, 5, 10, and 15 μg/mL of hucMSC-derived exosomes significantly attenuated cell viability decrease and inhibited LDH release of injured EECs, but 1 μg/mL of hucMSC-derived exosomes had no effect on either cell viability or LDH release. Real-time PCR and ELISA analysis revealed that 10 μg/mL of hucMSC-derived exosomes significantly inhibited the release of interleukin-6 (IL-6) and interleukin-1 beta (IL-1β) and increased tumor necrosis factor alpha (TNFA) in injured EECs. In addition, 10 μg/mL of hucMSC-derived exosomes significantly inhibited toll-like receptor 4 (TLR4) and v-rel reticuloendotheliosis viral oncogene homolog A (RelA) expression in injured EECs.
Conclusions: In OGD/R-induced injured EECs, hucMSC-derived exosomes efficiently improved the cell viability, reduced cell death, and exhibited anti-inflammatory properties against OGD/R.
Keywords: Endometrial epithelial cells; Exosome; Human umbilical cord mesenchymal stem cells; Injury.