[Heat shock protein 90 in male reproduction].

Heat shock protein 90 (Hsp90), as a member of the Hsp family and widely found in the gonads of humans and animals, plays an essential role in male reproduction and induces various changes in the process of reproduction. Hsp90 regulates the division of germ cells and participates in spermatogenesis, location of germ cells, formation of sperm microtubes, protection of sperm from oxidative stress, and inducement of acrosomal reaction. Studies showed significant changes in location and expression of Hsp90 in the sperm of oligospermia and asthenospermia patients. This paper presents an overview of Hsp90 in male reproduction and male infertility and a prospect of the treatment of male infertility.

[Role of CYCS in the cytogenesis and apoptosis of male germ cells and its clinical application].

In order to maintain the stability of intracellular environment, various cells die autonomously in vivo, which is called apoptosis. As a key factor of cell apoptosis in the mitochondrial pathway, cytochrome c, somatic (CYCS) plays an important role in the process of male spermatogenesis. Based on more than 40 recent studies on CYCS by Chinese and foreign scholars, this review focuses on the involvement of CYCS in the mechanisms of the apoptosis and anti-apoptosis of germ cells and in the regulation of their quality and activity and also outlines the role of CYCS in marking male reproductive performance as well as in male infertility and its underlying mechanisms.

A Novel Regulatory Axis, CHD1L-MicroRNA 486-Matrix Metalloproteinase 2, Controls Spermatogonial Stem Cell Properties.

Spermatogonial stem cells (SSCs) are unipotent germ cells that are at the foundation of spermatogenesis and male fertility. However, the underlying molecular mechanisms governing SSC stemness and growth properties remain elusive. We have recently identified chromodomain helicase/ATPase DNA binding protein 1-like (Chd1l) as a novel regulator for SSC survival and self-renewal, but how these functions are controlled by Chd1l remains to be resolved. Here, we applied high-throughput small RNA sequencing to uncover the microRNA (miRNA) expression profiles controlled by Chd1l and showed that the expression levels of 124 miRNA transcripts were differentially regulated by Chd1l in SSCs. KEGG pathway analysis shows that the miRNAs that are differentially expressed upon Chd1l repression are significantly enriched in the pathways associated with stem cell pluripotency and proliferation. As a proof of concept, we demonstrate that one of the most highly upregulated miRNAs, miR-486, controls SSC stemness gene expression and growth properties. The matrix metalloproteinase 2 (MMP2) gene has been identified as a novel miR-486 target gene in the context of SSC stemness gene regulation and growth properties. Data from cotransfection experiments showed that Chd1l, miR-486, and MMP2 work in concert in regulating SSC stemness gene expression and growth properties. Finally, our data also revealed that MMP2 regulates SSC stemness gene expression and growth properties through activating ß-catenin signaling by cleaving N-cadherin and increasing ß-catenin nuclear translocation. Our data demonstrate that Chd1l-miR-486-MMP2 is a novel regulatory axis governing SSC stemness gene expression and growth properties, offering a novel therapeutic opportunity for treating male infertility.

[The effect of microRNAs on the regulatory network of pluripotency in embryonic stem cells].

Embryonic stem cells (ESCs) are pluripotent stem cells characterized by their ability to self-renew and their pluripotency to differentiate into all cell types. MicroRNA (miRNA) is a small non-coding RNA molecule which can regulate transcriptional and post-transcriptional gene expression, and may also play significant roles in regulating proliferation and differentiation of ESCs. The maintenance of pluripotency in ESCs may involve a regulatory network of many factors and pathways regulated by miRNA, which includes ESCs transcription factors, cell cycle regulation, epigenetic modifications as well as intracelluar signal transduction. This review mainly elaborates the biogenesis of miRNA, the miRNA families regulating the pluripotency of ESCs, and the effect of miRNA on the regulatory network of pluripotency in ESCs.

[Studies on SNP and genomic imprinting of the PEG1 gene in swine].

PEG1 affects animal embryo growth and maternal behavior. The paternal allele-specific expression of PEG1 was reported in most animal species, but the expressive pattern of PEG1 was not clear in piglets born. In order to investigate the imprinting pattern of PEG1 in pig, 166 samples were used to SNP of PEG1 from Landrace, Yorkshire, and Lantang breeds by PCR-SSCP. Single nucleotide polymorphism (SNP) of PEG1 in exon 12 was identfied. The genotype frequency and the expressive pattern were anslyzed in swine by RT-PCR-RFLP/SSCP. One SNP (a G-->A transition) was identified in exon 12 of PEG1. Maternal expression of PEG1 exon 12 was observed in all major organs (stomach, thymus, pancreas, spleen, lung, muscle, liver, tongue, kidney, brain, bladder, and heart) and placenta of three heterozygous pigs. PEG1 was paternally expressed and maternally imprinted in swine.

[Selection of scaffolds of rat hepatocytes in three-dimension culture under simulated microgravity].

In order to investigate the biocompatibility, degradation and inflammatory reactions of poly benzyl glutamate (PBLG), poly lactic-co-glycolic acid (PLGA) and fibrin gel used as the scaffolds co-cultured with the hepatocytes of rats under simulated microgravity conditions in rotating wall vessel bioreactor (RWVB). PLGA is low biocompatibility, PBLG is medium biocompatibility with rat hepatocytes. Fibrin gel is high biocompatibility, no toxic degradation and no inflammatory reactions. Fibrin gel can be used as three dimensional scaffolds of rat hepatocytes under simulated microgravity.

[Effects of simulated microgravity on preimplantation embryonic development of Kunming mouse in vitro].

In order to investigate the development of Kunming mouse preimplantation embryos cultured in vitro under simulated microgravtiy, one-cell and 4-cell embryos of Kunming mouse (Fertilization In Situ) were cultured in CZB or KSOM media under simulated microgravity or normal gravity environment respectively. The results showed that under normal gravity, the percentage of passing 2-cell development block embryos was not different in CZB with in KSOM, but the percentage of blastocysts was lower in CZB than that in KSOM significantly. The percentages of passing 2-cell development block embryos and blastocysts in CZB or KSOM were lower under simulated microgravity than those under normal gravity. It is suggested that the frequency of early embryonic lethality is possibly increased by simulated microgravity.