Participation of the oviductal s100 calcium binding protein G in the genomic effect of estradiol that accelerates oviductal embryo transport in mated rats

<p>Abstract</p> <p>Background</p> <p>Mating changes the mechanism by which E2 regulates oviductal egg transport, from a non-genomic to a genomic mode. Previously, we found that E2 increased the expression of several genes in the oviduct of mated rats, but not in unmated rats. Among the transcripts that increased its level by E2 only in mated rats was the one coding for an s100 calcium binding protein G (s100 g) whose functional role in the oviduct is unknown.</p> <p>Methods</p> <p>Herein, we investigated the participation of s100 g on the E2 genomic effect that accelerates oviductal transport in mated rats. Thus, we determined the effect of E₂on the mRNA and protein level of s100 g in the oviduct of mated and unmated rats. Then, we explored the effect of E₂on egg transport in unmated and mated rats under conditions in which s100 g protein was knockdown in the oviduct by a morpholino oligonucleotide against s100 g (s100 g-MO). In addition, the localization of s100 g in the oviduct of mated and unmated rats following treatment with E₂was also examined.</p> <p>Results</p> <p>Expression of <it>s100 g </it>mRNA progressively increased at 3-24 h after E2 treatment in the oviduct of mated rats while in unmated rats <it>s100 g </it>increased only at 12 and 24 hours. Oviductal s100 g protein increased 6 h following E₂and continued elevated at 12 and 24 h in mated rats, whereas in unmated rats s100 g protein increased at the same time points as its transcript. Administration of a morpholino oligonucleotide against <it>s100 g </it>transcript blocked the effect of E₂on egg transport in mated, but not in unmated rats. Finally, immunoreactivity of s100 g was observed only in epithelial cells of the oviducts of mated and unmated rats and it was unchanged after E2 treatment.</p> <p>Conclusions</p> <p>Mating affects the kinetic of E2-induced expression of s100 g although it not changed the cellular localization of s100 g in the oviduct after E₂. On the other hand, s100 g is a functional component of E2 genomic effect that accelerates egg transport. These findings show a physiological involvement of s100 g in the rat oviduct.</p

In Vitro maturation of fully grown mouse antral follicles in the presence of 1 nM 2-Hydroxyestradiol improves Oocytes’ developmental competence

Cathecolestrogens are estradiol metabolites produced during folliculogenesis in the mammalian ovary. 2-Hydroxyestradiol (2-OHE2) is one of the most abundant although its role remains unknown. The aim of this study is to investigate whether the presence of 2-OHE(2)during the germinal vesicle-to-metaphase II transition affects oocyte meiotic and preimplantation developmental competence. Mouse cumulus-oocyte complexes (COCs), isolated from fully grown antral follicles, were in vitro-matured (IVM) in the presence of 2-OHE2(0.1, 1, 10 or 100 nM) for 6 or 15 h; then, their meiotic and developmental competence was evaluated using a number of cytological quality markers. With the exception of the highest dose (100 nM), the addition of 2-OHE(2)to the IVM medium, did not alter, compared with untreated control, the frequency of oocytes that reached the MII stage. Instead, IVM in the presence of 1 nM 2-OHE(2)highly increased the rate of preimplantation development and blastocyst quality. To understand whether this positive effect could be attributed to the events occurring during meiosis resumption, we analysed a number of specific cytological quality markers of the asymmetric division, such as PB-I volume and position, presence and extension of the cortical F-actin cap, meiotic spindle shape and area, and microtubule organisation centre localisation. The results highlighted how the presence of 1 nM 2-OHE(2)significantly improved the overall cytological organisation required for a correct asymmetric division. Our results contribute a first step to acknowledge a potential role of this estradiol metabolite during the GV-to-MII transition, contributing to the acquisition of oocytes developmental competence.Universita degli Studi di Pavia within the CRUI-CARE Agreement Merck-MilliQ Laboratory Water Solution

46,XX/SRY-negative true hermaphrodite

Objective: To describe genetic evaluation and response to surgery and letrozole therapy of a 46,XX/SRY-negative true hermaphrodite. Design: Case report. Setting: University Medical Center. Patient(s): Nineteen-year-old male with penile hypospadias, micropenis, and crytorchidism at the time of birth. Intervention(s): Unilateral gonadectomy, and contralateral conservative gonadal surgery, followed by therapy with letrozole. Main Outcome Measure(s): Histopathologic, genetic and hormonal studies. Result(s): Genetic analysis showed that the subject was 46,XX/SRY-negative. Gonadectomy of the left gonad was performed at 16 years. The gonad resected was an ovotestes. The patient's estradiol was high (492 ± 25 pmol/L), whereas the testosterone was low (4.2 ± 0.5 nmol/L). Nineteen months later, conservative gonadal surgery of the contralateral gonad was performed to resect ovarian tissue, and treatment with letrozole was started. During letrozole treatment, testosterone was significantly increa

The Role of Mating in Oviduct Biology

The oviduct connects the ovary to the uterus, and is subject to changes that influence gamete transport, fertilization, and early embryo development. The ovarian steroids estradiol and progesterone are largely responsible for regulating oviduct function, although mating signals also affect the female reproductive tract, both indirectly, through sensory stimulation, and directly, through contact with seminal plasma or spermatozoa. The resulting alterations in gene and protein expression help establish a microenvironment that is appropriate for sperm storage and selection, embryo development, and gamete transport. Mating may also induce the switch from a non-genomic to a genomic pathway of estradiol-accelerated oviduct egg transport, reflecting a novel example of the functional plasticity in well-differentiated cells. This review highlights the physiological relevance of various aspects of mating to oviduct biology and reproductive success. Expanding our knowledge of the mating-associated molecular and cellular events in oviduct cells would undoubtedly facilitate new therapeutic strategies to treat infertility attributable to oviduct pathologies.FONDECYT 1080523 1110662 11121491 Proyecto BASAL FB0807 Proyectos Basales y Vicerrectoria de Investigacion, Desarrollo e Innnovacio

Prolactin gene expression in the pituitary of rats subjected to vaginocervical stimulation requires Erk-1/2 signaling

Vaginocervical stimulation (VCS) induces twice-daily prolactin (PRL) surges resulting in pseudopregnancy in the rat. Furthermore, activation of the extracellular signal-regulated kinase-1/2 (Erk-1/2) is involved in the effect of estradiol (E-2) on the Prl gene expression in pituitary cells. Herein, we investigated whether Erk-1/2 signaling is involved in the control of Prl expression in the pituitary of VCS rats and whether VCS regulates the effect of E-2 on Erk-1/2 and Prl in the pituitary. Estrous rats were assigned as control or VCS groups and 0, 6, 12 or 24 h later the levels and localization of phosphorylated Erk-1/2 (p-Erk-1/2) were analyzed in the pituitary. The effect of an Erk-1/2 inhibitor PD98059 on the Prl level in the pituitary of control or VCS rats was also analyzed. Other control or VCS rats were treated with E-2 and the level of p-Erk-1/2 and Prl were measured in the pituitary. In control rats, p-Erk-1/2 decreased at 6 and 12 h and increased at 24 h while Erk-1/2 was phosphorylated at all time points in VCS rats. p-Erk-1/2 was localized only in the anterior pituitary. PD98059 decreased Prl level in VCS, but not in control rats. Estradiol decreased Erk-1/2 phosphorylation although did not change Prl level in the pituitary of control or VCS rats. Theie findings show that prolonged activation of Erk-1/2 is necessary to induce Prl expression in the pituitary of VCS rats; however, VCS does not influence the role of E-2 on the activation of Erk-1/2 and Prl expression the pituitary.FONDECYT1110662 / BASALFB0807 / DICYT Regular021543OD / DICYT Asociativo0217430D_DA