PSXII-23 Sirtuins expression and activity in bovine granulosa cells are regulated by hormones that influence ovarian steroidogenesis

Sirtuins (SIRTs) are a family of seven NAD+-dependent histone deacetylases that regulate several biological reactions. How SIRTs regulate ovarian steroidogenesis in cattle remains to be fully unveiled. We hypothesize that SIRTs expression and activity are regulated by hormones that influence steroidogenesis in bovine granulosa cells (GC). Bovine ovaries were collected at an USDA-inspected commercial slaughterhouse and GC were isolated from small antral follicles (1–5 mm on surface diameter). Cells were treated with hormones that regulate ovarian folliculogenesis: FSH, IGF1, fibroblast growth factor (FGF) 2, FGF9, and their combinations. Cells were cultured for 24h for total RNA isolation (n = 6 pools) with miRNeasy microkit (Qiagen) or for 48h for isolation of nuclear and cytoplasmic extracts (n = 3 pools) with EpiQuik Nuclear Extraction Kit (Epigentek) according to the manufacturers’ instructions. Relative mRNA abundance was quantified via qPCR and expressed as 2-ΔΔCt using the relative comparative threshold cycle (Ct) whereas SIRTs activity in nuclear (SIRTs 1, 6, and 7) and cytoplasmic (SIRTs 2, 4, and 5) extracts was analyzed with the Epigenase Universal SIRT Activity/Inhibition assay kit (Epigentek) following the manufacturer’s instructions. Data were analyzed via ANOVA with GLM procedures of SAS for Windows. In terms of mRNA relative abundance, FSH+IGF1+IGF9 increased mRNA relative expression of SIRTs 2 to 7 in comparison to negative control and of SIRTs 2, 3, 4, 6, and 7 in comparison to FSH+IGF1; FSH+IGF1+IGF2 increased mRNA relative abundance of SIRTs 2 and 6 in comparison to FSH+IGF1; FGF2 alone increased SIRT1 in comparison to negative control (P < 0.05). In term of SIRTs activity, FGF2 alone increased nuclear SIRTs activity in comparison to FSH, IGF1, FSH+IGF1, and FGF9 alone; FSH+IGF1+IGF2 increased cytoplasmic SIRTs activity in comparison to all treatments (P < 0.05). Taken together, our data demonstrate that SIRTs expression and activity in bovine GC are regulated by hormones that influence steroidogenesis.

Ovarian Folliculogenesis and Uterine Endometrial Receptivity after Intermittent Vaginal Injection of Recombinant Human Follicle-Stimulating Hormone in Infertile Women Receiving In Vitro Fertilization and in Immature Female Rats

The uterine first-pass effect occurs when drugs are delivered vaginally. However, the effect of vaginally administered recombinant human follicle-stimulating hormone (rhFSH) on ovarian folliculogenesis and endometrial receptivity is not well established. We aimed to compare the efficacy of rhFSH administered vaginally and abdominally in clinical in vitro fertilization (IVF) treatment, pharmacokinetic study, and animal study. In IVF treatment, the number of oocytes retrieved, endometrial thickness and uterine artery blood perfusion were not different between women who received the rhFSH either vaginally or abdominally. For serum pharmacokinetic parameters, significantly lower Tmax, clearance, and higher AUC and T1/2_elimination of rhFSH were observed in women who received rhFSH vaginally, but urine parameters were not different. Immature female rats that received daily abdominal or vaginal injections (1 IU twice daily for 4 days) or intermittent vaginal injections (4 IU every other day for two doses) of rhFSH had more total follicles than the control group. In addition, the serum progesterone and progesterone receptors in the local endometrium were significantly higher in the groups treated with intermittent abdominal or vaginal injection of rhFSH, compared with those who recieved daily injection. In summary, vaginal administration of rhFSH may provide an alternative treatment regimen in women receiving IVF.

Perinatal exposure to a human relevant mixture of persistent organic pollutants: Effects on mammary gland development, ovarian folliculogenesis and liver in CD-1 mice

The ability of persistent organic pollutants (POPs) with endocrine disrupting properties to interfere with the developing reproductive system is of increasing concern. POPs are transferred from dams to offspring and the high sensitivity of neonates to endocrine disturbances may be caused by underdeveloped systems of metabolism and excretion. The present study aimed to characterize the effect of in utero and lactational exposure to a human relevant mixture of POPs on the female mammary gland, ovarian folliculogenesis and liver function in CD-1 offspring mice. Dams were exposed to the mixture through the diet at Control, Low or High doses (representing 0x, 5000x and 100 000x human estimated daily intake levels, respectively) from weaning and throughout mating, gestation, and lactation. Perinatally exposed female offspring exhibited altered mammary gland development and a suppressed ovarian follicle maturation. Increased hepatic cytochrome P450 enzymatic activities indirectly indicated activation of nuclear receptors and potential generation of reactive products. Hepatocellular hypertrophy was observed from weaning until 30 weeks of age and could potentially lead to hepatotoxicity. Further studies should investigate the effects of human relevant mixtures of POPs on several hormones combined with female reproductive ability and liver function.

Imaging the communicating structures on oocyte through high-resolution spinning-disc microscope

The communications between oocyte and granulosa cells are essential for ovarian folliculogenesis in mammals, and the communicating structures in the ZP had been widely reported. However, there was lack of direct approach to visualize these structures in a 3D model with a high-resolution. Here, we present a protocol to image the structures which derived from oocytes by combining endogenous fluorescent mouse models with a high-resolution spinning disc-confocal system in details

Signalling pathways and mechanistic cues highlighted by transcriptomic analysis of primordial, primary, and secondary ovarian follicles in domestic cat

In vitro growth (IVG) of dormant primordial ovarian follicles aims to produce mature competent oocytes for assisted reproduction. Success is dependent on optimal in vitro conditions complemented with an understanding of oocyte and ovarian follicle development in vivo. Complete IVG has not been achieved in any other mammalian species besides mice. Furthermore, ovarian folliculogenesis remains sparsely understood overall. Here, gene expression patterns were characterised by RNA-sequencing in primordial (PrF), primary (PF), and secondary (SF) ovarian follicles from Felis catus (domestic cat) ovaries. Two major transitions were investigated: PrF-PF and PF-SF. Transcriptional analysis revealed a higher proportion in gene expression changes during the PrF-PF transition. Key influencing factors during this transition included the interaction between the extracellular matrix (ECM) and matrix metalloproteinase (MMPs) along with nuclear components such as, histone HIST1H1T (H1.6). Conserved signalling factors and expression patterns previously described during mammalian ovarian folliculogenesis were observed. Species-specific features during domestic cat ovarian folliculogenesis were also found. The signalling pathway terms “PI3K-Akt”, “transforming growth factor-β receptor”, “ErbB”, and “HIF-1” from the functional annotation analysis were studied. Some results highlighted mechanistic cues potentially involved in PrF development in the domestic cat. Overall, this study provides an insight into regulatory factors and pathways during preantral ovarian folliculogenesis in domestic cat.

Androgen Receptor Is Dispensable for X-Zone Regression in the Female Adrenal but Regulates Post-Partum Corticosterone Levels and Protects Cortex Integrity

Adrenal androgens are fundamental mediators of ovarian folliculogenesis, embryonic implantation, and breast development. Although adrenal androgen function in target tissues are well characterized, there is little research covering the role of androgen-signaling within the adrenal itself. Adrenal glands express AR which is essential for the regression of the X-zone in male mice. Female mice also undergo X-zone regression during their first pregnancy, however whether this is also controlled by AR signaling is unknown. To understand the role of the androgen receptor (AR) in the female adrenal, we utilized a Cyp11a1-Cre to specifically ablate AR from the mouse adrenal cortex. Results show that AR-signaling is dispensable for adrenal gland development in females, and for X-zone regression during pregnancy, but is required to suppress elevation of corticosterone levels post-partum. Additionally, following disruption to adrenal AR, aberrant spindle cell development is observed in young adult females. These results demonstrate sexually dimorphic regulation of the adrenal X-zone by AR and point to dysfunctional adrenal androgen signaling as a possible mechanism in the early development of adrenal spindle cell hyperplasia.