Peroxiredoxin 4, a new oxidative stress marker in follicular fluid may predict IVF outcomes

Abstract

For better predicting in vitro fertilization (IVF) outcomes, it is necessary to identify some non-invasive and sensitive markers. Studies indicated that oxidative stress status in patients was closely associated with IVF outcomes, while the results are still controversial. Prdx4 as one member in Prdx family, can catalyze the reduction of reactive oxygen species. While little data on the relationship of Prdx4 and female reproduction were demonstrated. Our study is a prospective clinical study. All participants were recuited in the center of clinical reproductive medicine from September 2017 to December 2018. Infertile women with either tubal factor or male factor (n = 138) undergoing controlled ovarian hyperstimulation and IVF were recruited in our study. FF samples from patients were collected on the day of oocyte collection and then centrifuged and frozen up for analysis. Prdx4 concentration in FF were measured in each participant. Furthermore, the correlation between Prdx4 level and IVF outcomes, such as clinical pregnancy rate and oocyte quality was analyzed. And subsequently, we divided all participants into three groups according to their levels of Prdx4 in FF (low, moderate and high group), then the clinical pregnancy rate and oocyte quality outcomes were all analyzed. The pregnant women had higher levels of Prdx4 in FF than non-pregnant women. Prdx4 was positively correlated with oocyte fertilization rates (r = 0.326; p = 0.013) and good quality embryo rates (r = 0.334; p = 0.011). Furthermore, we found the pregnancy rate was positive correlated to Prdx4 level with a concentration dependent manner in three groups (pregnancy rate were 28.1%, 46.8% and 70.3% in low, moderate and high group, respectively). In the oocyte quality outcomes, the fertilization rates were significantly higher in the high group than the low group (p < 0.01), and the good quality embryo rates of moderate (p < 0.01) and high (p < 0.01) groups were significantly higher than the low group. Our results provide evidence that the upregulated expression of antioxidants in IVF patients follicular fluid (FF), such as Prdx4, tend to increase the potential pregnancy via oocyte quality mechanism.