Supplementation with Eupatilin during In Vitro Maturation Improves Porcine Oocyte Developmental Competence by Regulating Oxidative Stress and Endoplasmic Reticulum Stress

Simple Summary The in vitro maturation of oocytes is important for animal husbandry and assisted reproductive technology, but due to the higher oxidative stress in the in vitro environment compared with the in vivo environment, it is necessary to improve the efficiency of this process by alleviating in vitro oxidative stress. Eupatilin is a flavonoid compound with various activities, such as anti-inflammatory, anti-oxidant, and anti-tumoral activities. It is currently unclear whether it can reduce oxidative stress and improve the efficiency of the in vitro maturation of oocytes. The results of this study indicate that adding eupatilin to the in vitro maturation medium can alleviate oxidative stress, endoplasmic reticulum stress, and DNA damage in oocytes, further stimulating the maturation rate and embryo rate of porcine oocytes. It is expected to improve in vitro maturation efficiency and improve the composition of the medium. Eupatilin (5,7-dihydroxy-3 ',4 ',6-trimethoxyflavone) is a flavonoid derived from Artemisia plants that has beneficial biological activities, such as anti-apoptotic, anti-oxidant, and anti-inflammatory activities. However, the protective effects of eupatilin against oxidative stress and endoplasmic reticulum stress in porcine oocyte maturation are still unclear. To investigate the effect of eupatilin on the development of porcine oocytes after in vitro maturation and parthenogenetic activation, we added different concentrations of eupatilin in the process of porcine oocyte maturation in vitro, and finally selected the optimal concentration following multiple comparisons and analysis of test results using SPSS (version 17.0; IBM, Chicago, IL, USA) software. The results showed that 0.1 mu M eupatilin supplementation did not affect the expansion of porcine cumulus cells, but significantly increased the extrusion rate of porcine oocyte polar bodies, the subsequent blastocyst formation rate, and the quality of parthenogenetically activated porcine embryos. Additionally, it reduced the level of reactive oxygen species in cells and increased glutathione production. Further analysis revealed that eupatilin supplementation could reduce apoptosis, DNA double-strand breaks, and endoplasmic reticulum stress. In conclusion, supplementation with 0.1 mu M eupatilin during in vitro maturation improved oocyte maturation and subsequent embryo development by reducing oxidative stress and endoplasmic reticulum stress.