Oocyte Vitrification Temporarily Turns on Oxidation-Reduction Process Genes in Mouse Preimplantation Embryos.

We aim to understand how oocyte vitrification impacts subsequent mouse preimplantation embryo development at molecular level. We profiled transcriptomics of fertilized preimplantation embryos derived from mouse vitrified-warmed oocytes. Concomitantly, we evaluated epigenetic markers in fertilized preimplantation embryos. We found that oocyte vitrification did not affect the fertilization and cleavage process but delayed embryo development until blastocyst stage. RNA sequencing revealed that 1575 genes were profoundly altered in the 2-cell stage embryos developed from vitrified oocytes. The most significantly altered biological pathway was "oxidation-reduction process." Such profound transcriptomics change was associated with decreased level of oocyte-specific histone H1FOO in zygote and 2-cell stage. Transcriptome alteration due to oocyte vitrification was less pronounced as embryos develop into the morula stage. Oocyte vitrification temporarily changes transcriptomics in early preimplantation embryos. Targeting oxidation-reduction pathway might be a potential therapeutic strategy to improve embryo quality and long-term embryo survival.

Relationship between follicular fluid oxidative stress parameters and body mass index in patients with polycystic ovary syndrome / 中华内分泌代谢杂志

Objective To study the relationship between reactive oxygen species (ROS) as well as total antioxidant capacity ( TAC ) within follicle fluid and body mass index ( BMI ) in patients with polycystic ovary syndrome (PCOS).Methods All patients enrolled in this study were infertile women receiving in vitro fertilization-embryo transfer (IVF-ET) treatment.55 PCOS patients were divided into over-weight group ( n =23 ) and non-over-weight group ( n =32 ).Another 55 age-matched non-PCOS women were also divided into control group ( n =30) and overweight group ( n =25 ).Plasma sex hormone,triglycerides,and total cholesterol were determined.On oocyte retrieval day after ovarian stimulation,ROS and TAC in follicular fluid were assayed.Results Subjects in over-weight and PCOS over-weight groups had higher triglycerides than those in control and PCOS non-over-weight groups [ ( 1.9 ±1.1,1.7 ± 0.9,1.0 ± 0.5,1.2 ± 0.7 ) mmol/L,respectively,all P＜0.05],so did total cholesterol [ ( 4.8 ± 1.2,5.2 ± 1.1,4.0 ± 0.6) mmol/L,respectively,all P＜0.05].In PCOS over-weight group,ROS and ROS/TAC within follicular fluid were ( 35.4 ± 6.7 ) RLU/S and 39.8 ± 22.0,both were higher than those in the other 3 groups ( all P＜0.05).TAC [ (0.8 ± 0.5 ) Mm] was lower in PCOS over-weight group than that among the other 3 groups( all P＜0.05 ).ROS/TAC was higher in PCOS non-over-weight group than that of control group ( 26.5 ± 14.5 vs 14.2 ± 12.5,P＜0.05 ).Univariate analysis showed that both ROS and ROS/TAC within follicular fluid in PCOS patients were positively correlated with BMI ( r =0.34 and r =0.32,both P＜0.05 ).Conclusion Abnormal oxidative stress exists in follicular fluid of PCOS patients,and the oxidative stress parameters show positive correlation with BMI.

RNAi-mediated Stable Silencing of HGPRT Expression in Rabbit Fibroblasts and SCNT Embryo Production / 生物化学与生物物理进展

The hypoxanthine-guanine phosphoribosyl transferase (HGPRT) gene mutation is responsible for gouty arthritis, kidney stone, and Lesch-Nyhan Syndrome (LNS). It has been reported that the expression of HGPRT is decreased or even absent in these diseases. Rabbits are an ideal model for studying the pathology of these diseases. Therefore, the development of an HGPRT-knockdown rabbit model will be highly beneficial m such studies. Stable HGPRT-knoekdown transgenie fibroblast lines were generated by transfecting rabbit fibroblasts with RNA interference (RNAi) plasmids. Polymerase chain reaction (PCR) analyses indicated that the average positive rate was 83.3%. The mRNA and protein levels of HGPRT in the transgenic fibroblast lines were significantly lower than that in the control. Transgenic rabbit blastocysts were derived after performing nuclear transfer. The results show that RNAi can be used to stably knock down expression of the HGPRT in rabbit fibroblasts and further improvements in related technologies will facilitate the use of this method for the generation of HGPRT-knockdown rabbits.