EZH2 deletion promotes spermatogonial differentiation and apoptosis
Spermatogenesis is crucial for male fertility and is therefore tightly controlled by a variety of epigenetic regulators. However, the function of enhancer of zeste homolog 2 (EZH2) in spermatogenesis and the molecular mechanisms underlying its activity remain poorly defined. Here, we demonstrate that deleting EZH2 promoted spermatogonial differentiation and apoptosis. EZH2 is expressed in spermatogonia, spermatocytes and round and elongated spermatids from stage 9 to 11 but not in leptotene and zygotene spermatocytes. Knocking down Ezh2 in vitro using a lentivirus impaired self-renewal in spermatogonial stem cells (SSCs), ...
Source: Reproduction - October 5, 2017 Category: Reproduction Medicine Authors: Jin, C., Zhang, Y., Wang, Z.-P., Wang, X.-X., Sun, T.-C., Li, X.-Y., Tang, J.-X., Cheng, J.-M., Li, J., Chen, S.-R., Deng, S.-L., Liu, Y.-X. Tags: Research Source Type: research
Uterine flushings from women treated with levonorgestrel affect sperm functionality in vitro
In this study, we have evaluated the effects on human sperm functionality of uterine flushings (UF) obtained from women at day LH + 1 of a control cycle (CTR-LH + 1) and after receiving LNG (LNG-LH + 1) two days before the surge of LH. Human sperm from normozoospermic donors were incubated with UF and protein tyrosine phosphorylation, sperm motility, acrosome reaction as well as zona pellucida (ZP) binding capacity were assessed. A significant decrease in total motility and tyrosine phosphorylation accompanied by an increase on spontaneous acrosome reaction was observed when sperm were incubated in the presence of LNG-LH +...
Source: Reproduction - October 5, 2017 Category: Reproduction Medicine Authors: Chirinos, M., Durand, M., Gonzalez-Gonzalez, M. E., Hernandez-Silva, G., Maldonado-Rosas, I., Lopez, P., Larrea, F. Tags: Research Source Type: research
The critical role of uterine CD31 as a post-progesterone signal in early pregnancy
CD31 has been shown to play a role in endothelial cell migration and angiogenesis, which are critical to the formation and function of the endometrium and myometrium in uterine development during early pregnancy. However, the role of CD31 in uterine receptivity during blastocyst implantation is poorly understood. The pregnancy rate in CD31–/– female mice mated with CD31+/+ male mice was higher than that observed in CD31+/+ female mice mated with CD31+/+ male mice. During the receptive phase of implantation, uterine glands were more developed in CD31–/– mice than in CD31+/+ mice, and the uterine weig...
Source: Reproduction - October 5, 2017 Category: Reproduction Medicine Authors: Lee, S.-H., Kim, B.-J., Kim, U.-H. Tags: Research Source Type: research
Sex steroids differentially regulate fshb, lhb and gnrhr expression in Atlantic cod (Gadus morhua)
Depending on the stage of gonad maturation, as well as other factors, gonadal steroids can exert either a positive or negative feedback at the brain and pituitary level. While this has been demonstrated in many teleost species, little is known about the nature of steroid feedback in Gadiform fish. Using an optimized in vitro model system of the Atlantic cod pituitary, the present study investigated the potential effects of two physiologically relevant doses of estradiol, testosterone (TS) or dihydrotestosterone (DHTS) on cell viability and gene expression of gonadotropin subunits (fshb/lhb) and two suggested reproduction-r...
Source: Reproduction - October 5, 2017 Category: Reproduction Medicine Authors: von Krogh, K., Bjorndal, G. T., Nourizadeh-Lillabadi, R., Hodne, K., Ropstad, E., Haug, T. M., Weltzien, F.-A. Tags: Research Source Type: research
Three-dimensional analysis of seminiferous tubules and spermatogenic waves in mice
The aim of the present study was to reconstruct seminiferous tubules and analyze spermatogenic waves in seminiferous epithelia in developing and adult mice using serial paraffin sections and high-performance three-dimensional (3D) reconstruction software. By labeling the basement membrane of seminiferous tubules with fluorescent immunohistochemistry or periodic acid-Schiff-hematoxylin staining, all seminiferous tubules were reconstructed in 9 testes from 9 different mice, 3 each at 0, 21 and 90 days (adult) postpartum. The 3D structure of seminiferous tubules, including the number and length of tubules as well as the numbe...
Source: Reproduction - October 5, 2017 Category: Reproduction Medicine Authors: Nakata, H., Sonomura, T., Iseki, S. Tags: Research Source Type: research
Interferon-tau promotes luteal endothelial cell survival and inhibits specific luteolytic genes in bovine corpus luteum
Interferon-tau (IFNT), a maternal recognition of pregnancy (MRP) signals in domestic ruminants, suppresses the release of luteolytic pulses of uterine prostaglandin F2a (PGF2a), thus extending the corpus luteum (CL) life span. We hypothesized that IFNT also exerts anti-luteolytic actions in bovine CL. To examine the direct effects of IFNT on bovine CL, luteal slices and enriched luteal endothelial cells (LECs) were utilized. We found that recombinant ovine IFNT (roIFNT) markedly elevates interferon-associated genes (STAT1, STAT2 and IRF9) and interferon-stimulated genes (ISGs: MX2, ISG15 and OAS1Y) in both models. Furtherm...
Source: Reproduction - October 5, 2017 Category: Reproduction Medicine Authors: Basavaraja, R., Przygrodzka, E., Pawlinski, B., Gajewski, Z., Kaczmarek, M. M., Meidan, R. Tags: Research Source Type: research
Embryo biopsy and development: the known and the unknown
Preimplantation genetic diagnosis (PGD) has been introduced in clinical practice as a tool for selecting ‘healthy’ embryos before their transfer in utero. PGD protocols include biopsy of cleaving embryos (blastomere biopsy (BB)) or blastocysts (trophectoderm biopsy (TB)), followed by genetic analysis to select ‘healthy’ embryos for transfer in utero. Currently, TB is replacing the use of BB in the clinical practice. However, based on the European Society of Human Reproduction and Embryology Preimplantation Genetic Diagnosis Consortium reports, BB has been used in >87% of PGD cycles for more than ...
Source: Reproduction - October 5, 2017 Category: Reproduction Medicine Authors: Zacchini, F., Arena, R., Abramik, A., Ptak, G. E. Tags: Reviews Source Type: research
Cellular and molecular responses of adult testis to changes in nutrition: novel insights from the sheep model
This review explores the cellular and molecular mechanisms that regulate spermatogenesis in the post-pubertal testis that is regressing in response to mild undernutrition, using the sexually mature male sheep as a model. Testis regression leads to reductions in daily sperm production and in the quality of ejaculated spermatozoa (poorer movement, DNA damage). There is also a reduction in spermatogenic efficiency that appears to be caused, at least partially, by increases in germ cell apoptosis. Sertoli cell number does not change with testis regression, although about 1% of Sertoli cells do appear to retain proliferative ab...
Source: Reproduction - October 5, 2017 Category: Reproduction Medicine Authors: Guan, Y., Martin, G. B. Tags: Reviews Source Type: research
Paracrine and endocrine actions of interferon tau (IFNT)
This review focuses on the paracrine and endocrine actions of interferon tau (IFNT) during pregnancy recognition and establishment in ruminants. Pregnancy recognition involves the suppression of the endometrial luteolytic mechanism by the conceptus to maintain progesterone production by the corpus luteum (CL). The paracrine antiluteolytic effects of conceptus-derived IFNT inhibit upregulation of oxytocin receptors in the endometrial epithelia of the uterus, thereby preventing the production of luteolytic prostaglandin F2 alpha (PGF2α) pulses. In the endometrium, IFNT induces or upregulates a large number of classical...
Source: Reproduction - October 5, 2017 Category: Reproduction Medicine Authors: Hansen, T. R., Sinedino, L. D. P., Spencer, T. E. Tags: Anniversary Review Source Type: research
Interferon-tau and fertility in ruminants
Establishment of pregnancy in domestic ruminants includes pregnancy recognition signalling by the conceptus, implantation and placentation. Despite the high fertilisation success rate in ruminants, a significant amount of embryo loss occurs, primarily during early gestation. Interferon-tau (IFNT), a type I interferon that is exclusively secreted by the cells of the trophectoderm of the ruminant conceptus, has been recognised as the primary agent for maternal recognition of pregnancy in ruminants. It produces its antiluteolytic effect on the corpus luteum by inhibiting the expression of oxytocin receptors in the uterine epi...
Source: Reproduction - October 5, 2017 Category: Reproduction Medicine Authors: Forde, N., Lonergan, P. Tags: Anniversary Review Source Type: research
Transcriptional control of IFNT expression
Once interferon-tau (IFNT) had been identified as a type I IFN in sheep and cattle and its functions were characterized, numerous studies were conducted to elucidate the transcriptional regulation of this gene family. Transfection studies performed largely with human choriocarcinoma cell lines identified regulatory regions of the IFNT gene that appeared responsible for trophoblast-specific expression. The key finding was the recognition that the transcription factor ETS2 bound to a proximal region within the 5'UTR of a bovine IFNT and acted as a strong transactivator. Soon after other transcription factors were identified ...
Source: Reproduction - October 5, 2017 Category: Reproduction Medicine Authors: Ezashi, T., Imakawa, K. Tags: Anniversary Review Source Type: research
Chronicling the discovery of interferon tau
It has been 38 years since a protein, now known as interferon tau (IFNT), was discovered in ovine conceptus-conditioned culture medium. After 1979, purification and testing of native IFNT revealed its unique antiluteolyic activity to prevent the regression of corpora lutea on ovaries of nonpregnant ewes. Antiviral, antiproliferative and immunomodulatory properties of native and recombinant IFNT were demonstrated later. In addition, progesterone and IFNT were found to act cooperatively to silence expression of classical interferon stimulated genes in a cell-specific manner in ovine uterine luminal and superficial glandular ...
Source: Reproduction - October 5, 2017 Category: Reproduction Medicine Authors: Bazer, F. W., Thatcher, W. W. Tags: Anniversary Review Source Type: research
The evolution of interferon-tau
Thirty years ago, a novel type I interferon (IFN) was identified by molecular cloning of cDNA libraries constructed from RNA extracted from ovine and bovine pre-implantation embryos. This protein was eventually designated as IFN-tau (IFNT) to highlight its trophoblast-dependent expression. IFNT function is not immune related. Instead, it interacts with the maternal system to initiate the establishment and maintenance of pregnancy. This activity is indispensable for the continuation of pregnancy. Our review will describe how IFNT evolved from other type I IFNs to function in this new capacity. IFNT genes have only been iden...
Source: Reproduction - October 5, 2017 Category: Reproduction Medicine Authors: Ealy, A. D., Wooldridge, L. K. Tags: Anniversary Review Source Type: research
A single dose of allopregnanolone affects rat ovarian morphology and steroidogenesis
(Source: Reproduction)
Source: Reproduction - September 25, 2017 Category: Reproduction Medicine Authors: Pelegrina, L. T., Caceres, A. R. R., Giuliani, F. A., Asensio, J. A., Parborell, F., Laconi, M. R. Tags: Erratum Source Type: research
Regulation and action of early growth response 1 in bovine granulosa cells
Fibroblast growth factors (FGF) modify cell proliferation and differentiation through receptor tyrosine kinases, which stimulate the expression of transcription factors including members of the early growth response (EGR) family. In ovarian granulosa cells, most FGFs activate typical response genes, although the role of EGR proteins has not been described. In the present study, we determined the regulation of EGR mRNA by FGFs and explored the role of EGR1 in the regulation of FGF-response genes. Addition of FGF1, FGF2, FGF4 or FGF8b increased EGR1 and EGR3 mRNA levels, whereas FGF18 increased only EGR1 mRNA abundance. No m...
Source: Reproduction - September 6, 2017 Category: Reproduction Medicine Authors: Han, P., Guerrero-Netro, H., Estienne, A., Cao, B., Price, C. A. Tags: Research Source Type: research
