绿原酸在湖羊卵母细胞玻璃化冷冻保存中的应用研究OA

To investigate the continuous protective effects of chlorogenic acid(CGA)during vitrification cryopreservation and post-thawing in vitro maturation(IVM)of Hu sheep germinal vesicle(GV)stage oocytes,GV oocytes were collected and divided into four groups:fresh control,frozen control,frozen-thawed low-concentration CGA(50 μmol/L),and frozen-thawed high-concentration CGA(100 μmol/L).Survival rate after thawing,first polar body(PB1)extrusion rate after IVM,reactive oxygen species(ROS)and glutathione(GSH)levels,superoxide dismutase(SOD)and catalase(CAT)activities,mitochondrial membrane potential(MMP),and ATP levels were measured,and cleavage and blastocyst rates following in vitro fertilization(IVF)were evaluated.The results showed that the oocyte survival rate,PB1 extrusion rate,relative GSH level,relative activities of antioxidant enzymes SOD and CAT,relative MMP level,relative ATP level,cleavage rate,and blastocyst rate were significantly lowered(P<0.01 or P<0.001)compared with the fresh control group,whereas the relative ROS level was significantly elevated(P<0.001).Compared with the frozen control group,the low-concentration CGA group showed significant improvements in oocyte survival rate,PB1 extrusion rate,relative GSH levels,relative activities of antioxidant enzymes SOD and CAT,relative MMP levels,relative ATP levels,cleavage rate,and blastocyst rate(P<0.05,P<0.01 or P<0.001),and a significant decrease in relative ROS levels(P<0.05).In contrast,no significant differences were detected in any parameters mentioned above between the high-concentration CGA group and the frozen control group(P>0.05).In conclusion,supplementation with 50 μmol/L CGA during vitrification cryopreservation and subsequent IVM of Hu sheep oocytes enhances frozen-thawed survival,maturation,and subsequent developmental competence by inhibiting oxidative stress,maintaining antioxidant enzyme activities,and improving mitochondrial function.