Search Results

The cellular nucleic acid-binding protein (CNBP), also known as zinc finger protein 9, is a highly conserved zinc finger protein that is strikingly conserved among vertebrates. Data collected from lower vertebrates showed that CNBP is expressed at high levels and distributed in the testes during spermatogenesis. However, the location and function of CNBP in mammalian testes are not well known. Here, by neonatal mouse testis culture and spermatogonial stem cells (SSC) culture methods, we studied the effect of CNBP knockdown on neonatal testicular development. Our results revealed that CNBP was mainly located in the early germ cells and Sertoli cells. Knockdown of CNBP using morpholino in neonatal testis culture caused disruption of seminiferous tubules, mislocation of Sertoli cells and loss of germ cells, which were associated with the aberrant Wnt/β-catenin pathway activation. However, knockdown of CNBP in SSC culture did not affect the survival of germ cells. In conclusion, our study suggests that CNBP could maintain testicular development by inhibiting the Wnt/β-catenin pathway, particularly by influencing Sertoli cells.

It is demonstrated that repeated superovulation has deleterious effects on mouse ovaries and cumulus cells. However, little is known about the effects of repeated superovulation on early embryos. Epigenetic reprogramming is an important event in early embryonic development and could be easily disrupted by the environment. Thus, we speculated that multiple superovulations may have adverse effects on histone modifications in the early embryos. Female CD1 mice were randomly divided into four groups: (a) spontaneous estrus cycle (R0); (b) with once superovulation (R1); (c) with three times superovulation at a 7-day interval (R3) and (d) with five times superovulation at a 7-day interval (R5). We found that repeated superovulation remarkably decreased the fertilization rate. With the increase of superovulation times, the rate of early embryo development was decreased. The expression of Oct4, Sox2 and Nanog was also affected by superovulation in blastocysts. The immunofluorescence results showed that the acetylation level of histone 4 at lysine 12 (H4K12ac) was significantly reduced by repeated superovulation in mouse early embryos (P < 0.01). Acetylation level of histone 4 at lysine 16 (H4K16ac) was also significantly reduced in pronuclei and blastocyst along with the increase of superovulation times (P < 0.01). H3K9me2 and H3K27me3 were significantly increased in four-cell embryos and blastocysts. We further found that repeated superovulation treatment increased the mRNA level of histone deacetylases Hdac1, Hdac2 and histone methyltransferase G9a, but decreased the expression level of histone demethylase-encoding genes Kdm6a and Kdm6b in early embryos. In a word, multiple superovulations alter histone modifications in early embryos.

Sperm motility, fertilization and embryo implantation are several important factors in reproduction. Except healthy state of sperm and embryo themselves, successful pregnancy is closely related to the status of female reproductive tract immune system. Increased immune cells in reproductive tract often leads to low sperm motility and low chance of embryo implantation, but the mechanisms remain not well clarified. The aim of this study is to investigate the direct effects of swine polymorphonuclear neutrophils (PMNs) on sperm or embryo in vitro and then try to clarify the molecular mechanisms undergoing the phenomenon. Swine sperm-triggered neutrophil extracellular traps (NETs) were observed by scanning electron microscopy (SEM). PMNs phagocytosis of sperms was examined by transmission electron microscopy (TEM). Sperm-triggered NETs were quantitated by Pico Green^®. Vital staining of the interaction between PMNs and embryo were observed by using confocal microscope. It was showed that PMNs were directly activated by sperm in the form of phagocytosis or casting NETs and that sperm-triggered-NETs formation was made up with DNA co-located with citrullinated histone 3 (citH3) and myeloperoxidase (MPO). In addition, the potential mechanism of NETs release was relevant to NADPH oxidase, ERK1/2 or p38 MAPK signaling pathways. Of great interest was that swine embryo was first found entangled in NETs in vitro, but the function and mechanism of this action in vivo fertilization still needed further investigation. In conclusion, this is the first report about swine sperm-induced NETs that entangle sperm and embryo, which might provide an entirely understanding of swine reproductive physiology and immunology.

Decidualization is essential for the successful establishment of pregnancy, and the dysregulated decidualization may lead to early pregnancy loss. It was previously reported by us that miR-3074-5p could promote apoptosis but inhibit invasion of human extravillous trophoblast (EVT) cells in vitro, and the expression level of miR-3074-5p in villus tissues of recurrent miscarriage (RM) patients was significantly increased. The aim of this study was to preliminarily explore the role of miR-3074-5p played in the decidualization of human endometrial stromal cells (ESCs). It was found that the decidual expression level of miR-3074-5p in RM patients was remarkably higher than that in the control group. The overexpression of miR-3074-5p in the immortalized human ESC line, T-HESCs, showed suppressive effects not only on the cell proliferation, as well as the intracellular expression levels of cyclin B1 (CCNB1), CCND1 and CCNE1 but also on the in vitro-induced decidualization. CLN8 mRNA, encoding an endoplasmic reticulum (ER)-associated membrane protein, was validated to be directly targeted by miR-3074-5p. And, the expression level of CLN8 was continuously increased along with the decidualization process, whereas down-regulated CLN8 expression could inhibit the decidualization of T-HESCs in vitro. Furthermore, contrary to the increased expression level of miR-3074-5p, a significantly decreased CLN8 expression was observed in decidual tissues of RM patients. Collectively, these data suggested that an increased miR-3074-5p expression in ESCs might cause early pregnancy failure by disturbing decidualization of ESCs via the miR-3074-5p/CLN8 pathway, providing a potential diagnostic and therapeutic target for RM.