MicroRNA-210 Regulates Endoplasmic Reticulum Stress and Apoptosis in Porcine Embryos

Endoplasmic reticulum (ER) stress can be triggered during in vitro embryo production and is a major obstacle to embryo survival. MicroRNA (miR)-210 is associated with cellular adaptation to cellular stress and inflammation. An experiment was conducted to understand the effects of miR-210 on in vitro embryo development, ER stress, and apoptosis; to achieve this, miR-210 was microinjected
into parthenogenetically activated embryos. Our results revealed that miR-210 inhibition significantly
enhanced the cleavage rate, blastocyst formation rate, and total cell number (TCN) of blastocysts, and reduced expression levels of XBP1 (p < 0.05). miR-210 inhibition greatly reduced the expression of ER stress-related genes (uXBP1, sXBP1, ATF4, and PTPN1) and Caspase 3 and increased the levels of NANOG and SOX2 (p < 0.05). A miR-210-mimic significantly decreased the cleavage, blastocyst
rate, TCN, and expression levels of XBP1 compared with other groups (p < 0.05). The miR-210-mimic impaired the expression levels of uXBP1, sXBP1, ATF4, PTPN1, and Caspase 3 and decreased the expression of NANOG and SOX2 (p < 0.05). In conclusion, miR-210 plays an essential role in porcine
in vitro embryo development. Therefore, we suggest that miR-210 inhibition could alleviate ER stress
and reduce apoptosis to support the enhancement of in vitro embryo production.