The aim of this study was to examine the expression and regulation of peroxisome proliferator-activated receptor delta (PPARdelta) gene in rat uterus during early pregnancy by in situ hybridization and immunohistochemistry. PPARdelta mRNA expression in the luminal epithelium was high on day 1 of pregnancy, gradually declined from day 2 and was undetectable on day 5 of pregnancy. However, expression in the glandular epithelium began to increase from day 2 and was high on day 5 of pregnancy. There was no detectable PPARdelta immunostaining in the luminal and glandular epithelium from day 1 to day 5. On day 6 of pregnancy when embryos implanted, PPARdelta mRNA and immunostaining were intense in the subluminal stroma at implantation sites. On days 7 and 8, there was strong expression of both PPARdelta mRNA and intense immunostaining in the decidualized area near the lumen. There was low expression of PPARdelta in the subluminal stroma and glandular epithelium under delayed implantation. After delayed implantation was terminated by oestrogen treatment and embryo implantation was initiated, both PPARdelta mRNA and immunostaining were strongly induced in the subluminal stroma. Intense PPARdelta immunostaining was observed in the decidua under artificial decidualization, while no detectable immunostaining was seen in the uninjected control horn. Retinoid X receptor (RXRalpha) immunostaining was seen in the subluminal stroma surrounding the implanting blastocyst on day 6 and in the decidual cells on days 7 and 8 of pregnancy. In conclusion, the high PPARdelta expression at implantation sites and in the decidual cells in rat uterus indicates that PPARdelta may play an important role during implantation and decidualization.
NZ Ding, XH Ma, HL Diao, LB Xu and ZM Yang
LJ Xiao, HL Diao, XH Ma, NZ Ding, K Kadomatsu, T Muramatsu and ZM Yang
Basigin is essential for fertilization and implantation. The aim of this study was to determine the expression and hormonal regulation of the basigin gene in the rat uterus during the peri-implantation period. Basigin mRNA was localized strongly in the luminal epithelium on day 1 of pregnancy and gradually decreased to a basal concentration from day 3 to day 5 of pregnancy. Basigin mRNA and protein were expressed strongly in the implanting blastocyst and primary decidua on day 6 of pregnancy. A similar expression pattern was also induced in the uterus after delayed implantation was terminated by oestrogen treatment and the embryo implanted, whereas expression was not detected during delayed implantation. Basigin expression was not detected on day 6 of pseudopregnancy. Basigin mRNA was expressed strongly in the decidua on days 7 and 8 of pregnancy. Furthermore, both basigin mRNA and protein were induced in the decidua during artificial decidualization. In addition, oestrogen stimulated strong expression of basigin mRNA in the uterine epithelium of ovariectomized rats. These findings indicate that basigin may play a role during implantation and decidualization in rats.
Jiahui Ding, Xiujuan Tan, Kunkun Song, Wenwen Ma, Jing Xiao and Mingmin Zhang
Controlled ovarian hyperstimulation (COH) is widely used for the treatment of infertility, while the long-term effects of COH on the reproductive function in female offspring are currently unknown. Based on the fact that COH could cause high E2 levels in women throughout pregnancy and excess estrogenic exposure during fetal development is harmful to subsequent adult ovarian function, we assumed the hypothesis that COH disrupts reproductive function in female offspring. To test this hypothesis, COH was induced in mice to obtain female offspring by pregnant mare serum gonadotropin (PMSG) and HCG, and then we evaluated pubertal transition, serum levels of E2, anti-Mullerian hormone (AMH), FSH and LH, mRNA expressions of Esr1, Amhr2, Fshr and Lhcgr in ovaries, number of follicles and ovarian histology. We also investigated the apoptosis of follicles by TUNEL; the mRNA expressions of Fas, FasL, Bax, Bcl2, and caspase 3, 8 and 9 by quantitative real-time PCR; and the protein expressions of cleaved-caspase (CASP) 3, 8 and 9 by Western blot. Moreover, we further observed estrous cyclicity in young adult offspring, performed follicle counting and measured the level of AMH in both serum and ovary. COH could induce detrimental pregnancy outcomes, as well as delayed pubertal transition and irregular estrous cycle due to the aberrant growth and maturation of follicles in female offspring. Our novel findings add new evidence to better understand the potential risks of COH on the reproductive function in female offspring, raising the awareness that COH could exert adverse effects on female offspring, rather than just obtain more oocytes for fertilization.
Anran Fan, Kuiying Ma, Xinglan An, Yu Ding, Peipei An, Guangqi Song, Lina Tang, Sheng Zhang, Peng Zhang, Wentao Tan, Bo Tang, Xueming Zhang and Ziyi Li
TET1 is implicated in maintaining the pluripotency of embryonic stem cells. However, its precise effects on induced pluripotent stem cells (iPSCs), and particularly on porcine iPSCs (piPSCs), are not well defined. To investigate the role of TET1 in the pluripotency and differentiation of piPSCs, piPSCs were induced from porcine embryonic fibroblasts by overexpression of POU5F1 (OCT4), SOX2, KLF4, and MYC (C-MYC). siRNAs targeting to TET1 were used to transiently knockdown the expression of TET1 in piPSCs. Morphological abnormalities and loss of the undifferentiated state of piPSCs were observed in the piPSCs after the downregulation of TET1. The effects of TET1 knockdown on the expression of key stem cell factors and differentiation markers were analyzed to gain insights into the molecular mechanisms underlying the phenomenon. The results revealed that knockdown of TET1 resulted in the downregulated expression of pluripotency-related genes, such as LEFTY2, KLF2, and SOX2, and the upregulated expression of differentiation-related genes including PITX2, HAND1, GATA6, and LEF1. However, POU5F1, M YC, KLF4, and NANOG were actually not downregulated. Further analysis showed that the methylation levels of the promoters for POU5F1 and M YC increased significantly after TET1 downregulation, whereas there were no obvious changes in the promoters of SOX2, KLF4, and NANOG. The methylation of the whole genome increased, while hydroxymethylation slightly declined. Taken together, these results suggest that TET1 may play important roles in the self-renewal of piPSCs and the maintenance of their characteristics by regulating the expression of genes and the DNA methylation.
Renjie Wang, Wei Pan, Lei Jin, Yuehan Li, Yudi Geng, Chun Gao, Gang Chen, Hui Wang, Ding Ma and Shujie Liao
Artificial intelligence (AI) has experienced rapid growth over the past few years, moving from the experimental to the implementation phase in various fields, including medicine. Advances in learning algorithms and theories, the availability of large datasets and improvements in computing power have contributed to breakthroughs in current AI applications. Machine learning (ML), a subset of AI, allows computers to detect patterns from large complex datasets automatically and uses these patterns to make predictions. AI is proving to be increasingly applicable to healthcare, and multiple machine learning techniques have been used to improve the performance of assisted reproductive technology (ART). Despite various challenges, the integration of AI and reproductive medicine is bound to give an essential direction to medical development in the future. In this review, we discuss the basic aspects of AI and machine learning, and we address the applications, potential limitations and challenges of AI. We also highlight the prospects and future directions in the context of reproductive medicine.