Reproduction, Fertility and Development
Number 6 2016
Oviducts synthesise macrophage migration inhibitory factor (MIF) to promote sperm capacitation and embryogenesis. We discovered that both obese and lean Japanese Black cows have suppressed expression of MIF mRNA and protein in the ampullae and isthmuses of their oviducts. Therefore, maternal nutritional condition may change expression of oviductal MIF, which plays important roles in fertilisation and early embryo development.
The aquaporin protein family allows the transport of water and other solutes through cell membranes and plays a role in reproductive physiology. The present work has studied, for the first time, the presence of AQP7 and AQP11 in boar spermatozoa. Although both were identified in this species, only AQP11 was found to be related to sperm quality.
Endothelin regulates oviductal motility, which is important for the transport of gametes and embryo. To define the endothelin system in the bovine oviduct, the production and target sites of endothelin were evaluated. All isoforms of endothelin are produced by epithelial cells and endothelin receptors localise in the smooth muscle, suggesting that the bovine oviduct possesses a local endothelin system.
Leukotrienes are involved in reproductive functions in cows; however, their particular role in endometrium is unknown. The aim of the study was to elucidate the actions of leukotriene B4 and C4 in the bovine uterus. We demonstrated that these eicosanoids are produced, secreted and act in the endometrium depending upon the luteal stage. The results indicate multiple actions of leukotrienes in the bovine reproductive tract.
OHSS is a disorder associated with ovarian stimulation and is characterised by ovarian enlargement and vascular permeability. The aim was to investigate the effect of follicular fluid from women at risk of OHSS, in the presence of an ANGPT1 inhibitor, on the chorioallantoic membrane assay and in endothelial cell culture. Our findings suggest that ANGPT1 increases pathophysiological angiogenesis in patients at risk of OHSS.
The growth of oocytes and the development of follicles require certain pathways involved in cell proliferation and survival. However, the mechanism of primordial follicle recruitment remains largely unknown. Inhibition of the Notch signalling pathway suppressed AKT phosphorylation and the proliferation of granulosa cells. Recruitment of primordial follicles was regulated by an interaction between the Notch and PI3K/AKT signalling pathways.
Defects in the molecular mechanisms involved in the production and normal functioning of spermatozoa could be a major cause of male factor infertility. We identified a strong association between the absence of a critical molecule in testicular germ cells and male factor infertility. Identification of such critical molecules and their subsequent use in diagnosing male factor infertility may improve infertility management strategies.
Although the number of oocytes in patients with polycystic ovary syndrome (PCOS) is usually greater than normal following ovulation stimulation, these oocytes are often of low quality. The aim of the present study was to investigate the effects of metformin and N-acetylcysteine (NAC) on follicular fluid parameters, as well as oocyte and embryo quality, in Iranian women with PCOS. We conclude that NAC improves oocyte and embryo quality, and could be administered as an alternative to metformin.
The first gel-based profiling of the rhesus monkey (Macaca mulatta) sperm-milieu proteome was established by a two-dimensional electrophoresis map. When compared with bull and human sperm-milieu proteins, those in the rhesus monkey had a close evolutionary relationship to human. It could be used as an ideal model for the development of diagnostic and therapeutic targets for infertility or contraception.
Cell–cell adhesion is important for cellular communication, cellular structure and steroidogenesis. The present study demonstrates that an ovulatory stimulus of human chorionic gonadotrophin (hCG) stimulates ovarian expression of the cell adhesion molecule CXADR-like membrane protein (CLMP). The hCG induction of Clmp mRNA is mediated through the protein kinase A signalling pathway by activation of the epidermal growth factor receptor and requires the synthesis of new protein. The temporal stimulation of ovarian CLMP may be important in cell adhesion events during ovulation and luteal formation.
Many factors are involved in the onset of reproductive activity in sheep, such as melatonin, its own receptor gene (MTNR1A) and kisspeptin (KiSS-1) gene. The aim of this study was to investigate if melatonin implants and MTNR1A and KiSS-1 gene polymorphisms can advance the first conception; we found that the G/G genotype of the MTNR1A gene improved the reproductive response to melatonin treatment. Understanding the mechanisms of melatonin function may improve reproductive performance in sheep.
There is growing evidence that viral infections of the genital tract may contribute to male infertility and cause orchitis. The present study was carried out to develop cell therapy for this disorder. We revealed that a combination of antiviral therapy and neonatal testis-cell transplantation is effective for restoration of murine spermatogenesis damaged by herpes simplex virus infection.
We localised hyaluronan (HA) synthases (HAS) 1–3 and their main receptor CD44 in sheep antral follicles, showing intense staining in granulosa cells. Analyses of hormonal regulation of the HA system in cultured sheep granulosa cells indicated differential regulation of HAS2, HAS3 and CD44 expression by oestradiol, insulin-like growth factor, insulin and gonadotropins.
Stress tolerance of gametes and embryos can be increased by preconditioning with hydrostatic pressure (HP) treatment. To study the effect of HP, mouse oocytes were treated, fertilised and then analysed by gene expression microarray at the 4-cell stage. The results revealed that numerous ribosomal genes were downregulated after HP treatment, suggesting that regulation of translation has a major role in hydrostatic pressure-induced stress tolerance.
The human methylenetetrahydrofolate reductase (MTHFR) gene, located at chromosome 1p36.3, is associated with male infertility. Previous reports reported that the common polymorphisms C677T, A1298C and G1793A may be related to infertility. This study shows that the C677T transition plays an important role in the change in affinity of the MTHFR–Flavin adenine dinucleotide binding site, increasing the risk of infertility.
Little is known about stability of reference genes during dominant follicle development. This study examined the expression of a number of granulosa cell genes during ovarian superstimulation and maternal aging in cattle. Results support the use of the geometric mean of four genes (UBE2D2, EIF2B2, GAPDH and SF3A1) for relative gene expression analyses of granulosa cells during maternal and follicular aging.
Genetic expression could be behind individual sensitivity to chemical substances. Here we show that individuals with innate low or high levels of germ-cell death have distinct gene expression and that levels of germ-cell death changed differentially after administration of amphetamine. This helps both to understand the exacerbated response to drugs by some individuals and to develop a rationale in individualised medicine.
Several reproductive aspects of Mongolian gerbil still remain unknown. This study determined the phases of sexual development of this rodent based on an integrative analysis of testicular morphology, hormonal data and sperm parameters. In terms of laboratory rodents, the gerbil has a similar reproductive profile with the rat. These reproductive data provide new foundations for future investigations involving toxicological or developmental studies with this species.
Skin cells are widely used as nuclear donors for producing cloned animals. We showed that treatment of these cells with certain chemical agents, which affect their DNA and the proteins associated with it, alters the characteristics and improves the clonability of these cells. This could help to improve the yield and quality of cloned embryos derived from skin cells.
The testicular interstitium is responsible for endocrine function in the testis. We have studied the cellular changes in two physiological processes of testicular involution, one reversible due to exposure to short photoperiod and the other irreversible due to ageing. These processes induce very different changes in the cells. These differences are probably related to cell turnover in the testicular interstitium and to the non-apoptotic but necrotic character of Leydig cell death.