ABSTRACT
Objective To investigate the gene expression profiles of peri-implantation endometrium of high responders during controlled ovarian hyperstimulation. Methods High responders with cancelled embryo-transfer during controlled ovarian hyperstimulation (high responder group, n=4) and healthy fertile volunteers (control group, n=3) were performed endometrial biopsies during peri-implantation. Histologic changes of endometrium were observed by HE staining, genes of differential expression were screened with microarrays Affymetrix U133A 2.0 and identified by Real-time PCR. The biological process analysis was performed by online biological information analysis tool PANTHER. Results The ehdometrium was in mid-secretory phase in control group, while development delay was found in some glandular organs in endometrium of high responder group. Three hundred and sixty-four genes of differential expression were screened, among which 233 were up-regulated genes and 131 were down-regulated genes. OPN, PLA2G2, DPPIV, IGFBP5 and SSAT were identified as endometrial function-related genes, whose Real-time PCR findings were positively correlated to gene signal values detected by microarray(r=0.44, P<0.01). PANTHER analysis indicated that genes of differential expression participated in the biological processes of cytokine signal transduction and immunological regulation. Conclusion Ovarian high response affects the gene expression profiles of peri-implantation endometrium, which may be one of the causes of sub-optimal endometrial receptivity.
ABSTRACT
Apoptosis of abnormal oocytes is essential for defective oocyte elimination during prepubertal ovary development, and the ubiquitin system regulates the cell apoptosis via the degradation of specific proteins. Ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) is a component of the ubiquitin system, and the UCH-L1-dependent apoptosis is important for spermatogenesis. In the present study, the change in the number of follicles and the expression of UCH-L1 in oocytes were determined in prepubertal mouse ovaries by immunohistochemical techniques. A significant decrease in the follicular pool was found in prepubertal mouse ovaries during the period of day 21 to day 28 after birth, and accordingly, the UCH-L1 protein expression was increased, to some degree in association with Jun activation domain-binding protein 1 (Jab1) and cyclin-dependent kinase inhibitor p27(Kipl). The increased UCH-L1 protein, together with the corresponding changes of Jab1 was detected in morphologically abnormal oocytes of prepubertal ovaries. Through the immunofluorescent colocalization, UCH-L1 was shown concentrating in abnormal oocytes, and a parallel change in Jab1 was also seen. The affinity analysis confirmed the interaction between UCH-L1 and Jab1 in ovaries. These results suggest that UCH-L1 plays an important role, possibly in association with Jab1 and p27(Kipl), in selective elimination of abnormal oocytes during mouse prepubertal development.