Abstract: 【Objective】 This study was aimed to investigate the protection of Gynostemma penttaphyllum polysaccharides (GPP) on mouse oocytes and mitochondria damaged by hydrogen peroxide (H₂O₂).【Method】 Mouse oocyte maturation oxidative stress model was constructed with H₂O₂,and GPP concentration was selected.Then oocytes at MⅡ stage were randomly divided into blank control group,H₂O₂ group (H₂O₂ was added in mature medium) and H₂O₂+GPP group (GPP was added in mature medium containing H₂O₂).The cleavage rate,4-cell rate,8-cell rate,morula rate and blastocyst rate of oocytes were measured after in vitro fertilization (IVF).Mito Tracker Red CMXRos was used to detect mitochondrial distribution and content,JC-1 mitochondrial membrane potential detection kit was used to detect mitochondrial membrane potential,the ATP detection kit was used to detect mitochondrial ATP content,and the morphology and chromosome distribution of mouse oocytes were observed by immunofluorescence staining.【Result】 The cleavage rate,4-cell rate,8-cell rate,morula rate and blastocyst rate,the mitochondrial content,mitochondrial membrane potential and ATP contents of oocytes in H₂O₂+GPP group were significantly higher than those in H₂O₂ group (P＜0.05),and the rates of spindle abnormality and chromosome abnormality were significantly lower than those in H₂O₂ group (P＜0.05),but there was no significant difference between H₂O₂+GPP and control groups(P＞0.05).【Conclusion】 GPP could improve the cleavage rate and blastocyst rate of H₂O₂-damaged mouse oocytes IVF,as well as the mitochondrial content,mitochondrial normal distribution,mitochondrial membrane potential and ATP content in oocytes,and reduce the spindle morphological abnormalities,chromosome morphological abnormalities and disordered arrangement,reducing mitochondrial dysfunction.

Key words: Gynostemma penttaphyllum polysaccharides (GPP); hydrogen peroxide (H₂O₂); oocyte; mouse; mitochondria