Progesterone Secretion Research Articles

Irisin modulates glucose metabolism and inhibits steroidogenesis in bovine granulosa cells.

Fertility in the dairy cow is low during the post-partum period of negative energy balance and high plasma irisin concentrations. This study shows irisin modulates granulosa cell glucose metabolism and impairs steroidogenesis. Fibronectin type III domain-containing 5 (FNDC5) is a transmembrane protein discovered in 2012 that is cleaved to release the adipokine-myokine, irisin. Originally described as an exercise hormone that browns white adipose tissue and increases glucose metabolism, irisin secretion also increases during periods of rapid adipose mobilization, such as the post-partum period in dairy cattle when ovarian activity is suppressed. The effect of irisin on follicle function is unclear and may be species-dependent. In this study, we hypothesized that irisin may compromise granulosa cell function in cattle using a well-established in vitro cell culture model. We detected FNDC5 mRNA and both FNDC5 and cleaved irisin proteins in follicle tissue and in follicular fluid. The abundance of FNDC5 mRNA was increased by the treatment of cells with the adipokine visfatin but not by other adipokines tested. The addition of recombinant irisin to granulosa cells decreased basal and insulin-like growth factor 1- and follicle-stimulating hormone-dependent estradiol and progesterone secretion and increased cell proliferation but had no effect on viability. Irisin decreased GLUT1, GLUT3, and GLUT4 mRNA levels in granulosa cells and increased lactate release in the culture medium. The mechanism of action is in part through MAPK3/1 but not Akt, MAPK14, or PRKAA. We conclude that irisin may regulate bovine folliculogenesis by modulating granulosa cell steroidogenesis and glucose metabolism.

Effects of BAMBI on luteinized follicular granulosa cell proliferation and steroid hormone production in sheep.

Bone morphogenetic protein and activin membrane-bound inhibitor (BAMBI) regulates mammalian ovarian follicle growth and maturation; however, its effect on luteinized granulosa cells (LGCs) in sheep ovarian follicles remains unknown. Here we explored the regulatory role of LGC functions and steroid hormone synthesis by BAMBI. Multiple sequence alignment revealed that the sheep BAMBI gene sequence was relatively conserved. Sheep LGCs were strongly positive for BAMBI. LGC proliferation increased when BAMBI was silenced and decreased when BAMBI was overexpressed. After BAMBI overexpression, the expression of CASP3, CASP8, CASP9, and BAX significantly increased, whereas that of BCL2 and the ratio of BCL2/BAX expression decreased. The opposite was observed after BAMBI silencing. CDKN1A, CCND1, and CCND2 were downregulated with BAMBI overexpression and upregulated with BAMBI silencing. Expression of steroid hormone-related genes (CYP11A1, STAR, and 3BHSD), except CYP19A1, significantly increased after BAMBI overexpression. Moreover, estrogen and progesterone secretion increased after BAMBI overexpression and decreased after BAMBI interference. The effect of the exogenous addition of bone morphogenetic protein 2 (BMP2) on GCs was similar to that of BAMBI overexpression. In conclusion, BAMBI can regulate the proliferation and steroid hormone synthesis of sheep LGCs, and BMP2 can affect LGCs as an activator of BAMBI. These findings provide a basis for further research on the physiological role of BAMBI.

The injections of mitochondrial fusion promoter M1 during proestrus disrupt the progesterone secretion and the estrous cycle in the mouse

After ovulation, the mitochondrial enzyme CYP11A1 cleavage the cholesterol into pregnenolone for progesterone synthesis, suggesting that mitochondrial dynamics play a vital role in the female reproductive system. The changes in the mitochondria dynamics throughout the ovarian cycle have been reported in literature, but the correlation to its role in the ovarian cycle remains unclear. In this study, mitochondrial fusion promotor, M1, was used to study the impact of mitochondria dynamics in the female reproductive system. Our results showed that M1 treatment in mice can lead to the disruptions of estrous cycles in vagina smears. The decrease in serum LH was recorded in the animal. And the inhibitions of progesterone secretion and ovulations were observed in ovarian culture. Although no significant changes in mitochondrial networks were observed in the ovaries, significant up-regulation of mitochondrial respiratory complexes was revealed in M1 treatments through transcriptomic analysis. In contrast to the estrogen and steroid biosynthesis up-regulated in M1, the molecules of extracellular matrix, remodeling enzymes, and adhesion signalings were decreased. Collectively, our study provides novel targets to regulate the ovarian cycles through the mitochondria. However, more studies are still necessary to provide the functional connections between mitochondria and the female reproductive systems.

Bisphenol A and bisphenol S both disrupt ovine granulosa cell steroidogenesis but through different molecular pathways

BackgroundOvarian granulosa cells (GC) are essential for the development and maturation of a proper oocyte. GC are sensitive to endocrine disruptors, including bisphenol A (BPA) and its analogue bisphenol S (BPS), plasticisers present in everyday consumer products. BPA exhibits greater binding affinity for the membrane oestrogen receptor (GPER) than for the nuclear oestrogen receptors (ERα and ERβ). Here, we analysed the effects of BPA and BPS on the steroidogenesis of ovine GC in vitro, as well as their early mechanisms of action, the ovine being a relevant model to study human reproductive impairment. Disruption of GC steroidogenesis might alter oocyte quality and consequently fertility rate. In addition, we compared the effects of a specific GPER agonist (G-1) and antagonist (G-15) to those of BPA and BPS. Ewe GC were cultured with BPA or BPS (10 or 50 µM) or G-1 (1 µM) and/or G-15 (10 µM) for 48 h to study steroidogenesis.ResultsBoth BPA and BPS (10 µM) altered the secretion of progesterone, however, only BPS (10 µM) affected oestradiol secretion. RNA-seq was performed on GC after 1 h of culture with BPA or BPS (50 µM) or G-1 (10 µM), followed by real-time PCR analyses of differentially expressed genes after 12, 24 and 48 h of culture. The absence of induced GPER target genes showed that BPA and BPS did not activate GPER in GC after 1 h of treatment. These molecules exhibited mainly independent early mechanisms of action. Gene ontology analysis showed that after 1 h of treatment, BPA mainly disrupted the expression of the genes involved in metabolism and transcription, while BPS had a smaller effect and impaired cellular communications. BPA had a transient effect on the expression of CHAC1 (NOTCH signalling and oxidative balance), JUN (linked to MAPK pathway), NR4A1 (oestradiol secretion inhibition), ARRDC4 (endocytose of GPCR) and KLF10 (cell growth, differentiation and apoptosis), while expression changes were maintained over time for the genes LSMEM1 (linked to MAPK pathway), TXNIP (oxidative stress) and LIF (cell cycle regulation) after 12 and 48 h, respectively.ConclusionIn conclusion, although they exhibited similar effects, BPA and BPS impaired different molecular pathways in GC in vitro. New investigations will be necessary to follow the temporal changes of these genes over time, as well as the biological processes involved.

An ex vivo ovulation system enables the discovery of novel ovulatory pathways and nonhormonal contraceptive candidates†.

Ovulation is an integral part of women's menstrual cycle and fertility. Understanding the mechanisms of ovulation has broad implications for the treatment of anovulatory diseases and the development of novel contraceptives. Now, few studies have developed effective models that both faithfully recapitulate the hallmarks of ovulation and possess scalability. We established a three-dimensional encapsulated in vitro follicle growth (eIVFG) system that recapitulates folliculogenesis and produces follicles that undergo ovulation in a controlled manner. Here, we determined whether ex vivo ovulation preserves molecular signatures of ovulation and demonstrated its use in discovering novel ovulatory pathways and nonhormonal contraceptive candidates through a high-throughput ovulation screening. Mature murine follicles from eIVFG were induced to ovulate ex vivo using human chorionic gonadotropin and collected at 0, 1, 4, and 8hours post-induction. Phenotypic analyses confirmed key ovulatory events, including cumulus expansion, oocyte maturation, follicle rupture, and luteinization. Single-follicle RNA-sequencing analysis revealed the preservation of ovulatory genes and dynamic transcriptomic profiles and signaling. Soft clustering identified distinct gene expression patterns and new pathways that may critically regulate ovulation. We further used this ex vivo ovulation system to screen 21 compounds targeting established and newly identified ovulatory pathways. We discovered that proprotein convertases activate gelatinases to sustain follicle rupture and do not regulate luteinization and progesterone secretion. Together, our ex vivo ovulation system preserves molecular signatures of ovulation, presenting a new powerful tool for studying ovulation and anovulatory diseases as well as for establishing a high-throughput ovulation screening to identify novel nonhormonal contraceptives for women.

MiR-202-5p Inhibits Lipid Metabolism and Steroidogenesis of Goose Hierarchical Granulosa Cells by Targeting ACSL3.

miRNAs are critical for steroidogenesis in granulosa cells (GCs) during ovarian follicular development. We have previously shown that miR-202-5p displays a stage-dependent expression pattern in GCs from goose follicles of different sizes, suggesting that this miRNA could be involved in the regulation of the functions of goose GCs; therefore, in this study, the effects of miR-202-5p on lipid metabolism and steroidogenesis in goose hierarchical follicular GCs (hGCs), as well as its mechanisms of action, were evaluated. Oil Red O staining and analyses of intracellular cholesterol and triglyceride contents showed that the overexpression of miR-202-5p significantly inhibited lipid deposition in hGCs; additionally, miR-202-5p significantly inhibited progesterone secretion in hGCs. A bioinformatics analysis and luciferase reporter assay indicated that Acyl-CoA synthetase long-chain family member 3 (ACSL3), which activates long-chain fatty acids for the synthesis of cellular lipids, is a potential target of miR-202-5p. ACSL3 silencing inhibited lipid deposition and estrogen secretion in hGCs. These data suggest that miR-202-5p exerts inhibitory effects on lipid deposition and steroidogenesis in goose hGCs by targeting the ACSL3 gene.

Effects of thyroid hormones on the functional state of bovine granulosa cells in vitro

Any dysfunction of the thyroid gland causes abnormal changes in the functioning of the reproductive system, primarily the ovaries. Therefore, the question of the possible direct effect of thyroid hormones on the bovine ovarian function by modulating the functional state or functional activity of granulosa cells seems relevantPurpose: to study in vitro the effect of thyroxine and triiodothyronine on the proliferative and steroidogenic activity, as well as apoptotic changes of bovine granulosa cells.Materials and methods. Granulosa cells were isolated from follicles with a diameter of 1-5 mm and precultured for two days in a medium containing 10 % serum. The cells were then placed in serum-free medium containing thyroxine (25-200 ng/mL) or triiodothyronine (0.5-4.0 ng/mL) and incubated for another 48 h. After culturing, the content of estradiol-17β and progesterone in the media was determined by ELISA. The proliferative activity and apoptotic changes in the cells were assessed by immunocytochemical assay, based on the expression level of proliferating cell nuclear antigen PCNA and pro-apoptotic protein Bax, respectively.Results. It was found that the proportion of cells with a positive reaction to PCNA increased 1.1 times (P<0.01) compared with that in the control at a triiodothyronine concentration of 1 ng/ml and did not change with its further increase to 4 ng/ml. In addition, the introduction of triiodothyronine at a concentration of 1 ng/ml into the medium led to a decrease in the relative number of Bax-positive cells from 25.6 ± 0.3% to 23.3 ± 0.6 % (P<0.01). A further increase in this concentration to 4 ng/ml enhanced the observed anti-apoptotic effect 1.1 times (P<0.05). The pattern of the effect of thyroxine on the proliferative activity and apoptotic changes of granulosa cells in culture was similar to that for triiodothyronine. Concurrently, the growth-stimulating and anti-apoptotic effects of thyroxine were achieved at a concentration of 50-200 ng/ml. At the same time, both thyroid hormones did not affect the secretion of estradiol-17β or progesterone by the cells.Conclusions. Thus, thyroxine and triiodothyronine can stimulate in vitro the proliferation of bovine granulosa cells, as well as inhibit the expression of the proapoptotic Bax protein in these cells, which is not associated with the regulation of the production of ovarian steroid hormones. Overall, these data suggest that thyroid hormones at physiological concentrations are able to exert a regulatory effect on the growth and atresia of bovine small antral follicles and, therefore, directly modulate the ovarian activity.

Sphingosine-1-phosphate regulation of luteinising hormone-induced steroidogenesis and proliferation of bovine theca cells in vitro.

Sphingosine-1-phosphate (S1P) is synthesised by follicle granulosa cells under the influence of follicle-stimulating hormone and seems to be necessary for the biological effects of this gonadotrophin. To determine if luteinising hormone (LH) increases S1P production and if this sphingolipid, either induced by LH or added to culture media, regulates steroidogenesis and cell viability in bovine theca cells. We used bovine theca cell cultures treated with: S1P (0, 0.1, 1 and 10μM; Experiment 1), LH (0, 0.02, 0.2 and 2ngmL-1; Experiment 2) and LH (0.02ngmL-1) plus a sphingosine kinase inhibitor (SKI-178; 0, 5 and 10μM; Experiment 3). Treatment with S1P did not affect (P>0.05) theca cell viability or their ability to produce progesterone and testosterone. LH (0.02ngmL-1) increased (P<0.05) S1P production, and stimulated the expression of phosphorylated sphingosine kinase-1 (pSPHK1). However, the inhibition of SPHK1, by a specific SPHK1 inhibitor (SKI-178), reduced (P<0.05) cell viability and progesterone secretion. Additionally, the use of SKI-178 increased theca cell testosterone production (P<0.05). S1P added to culture media did not affect cell viability or steroid synthesis. However, LH stimulated the production of S1P, by increasing phosphorylation of SPHK1 in theca cells. This intracellular S1P was inhibitory on testosterone production but augmented progesterone and viable cell number. These results suggest a novel signalling pathway for LH in theca cells and underline the importance of S1P in the regulation of steroid synthesis.

Pharmacodynamic structure of deer antler base protein and its mammary gland hyperplasia inhibition mechanism by mediating Raf-1/MEK/ERK signaling pathway activation.

Mammary gland hyperplasia (MGH) is a common mammary disease whose main pathogenesis is the disruption of estradiol (E2) and progesterone (P) secretion, thereby causing overproliferation of mammary epithelial cells and mammary gland tissue hyperplasia. Deer antler base is a traditional Chinese medicine that has been used for many years to treat MGH. However, its pharmacological mechanism and pharmacodynamic material basis are unclear. In this study, we for the first time used the graded salting method to classify deer antler base protein (CNCP) as CNCP-A, CNCP-B, and CNCP-C and explored the pharmacological mechanism of the anti-MGH properties of CNCP. We found that CNCP could regulate the hormonal levels of E2, P, and follicle stimulating hormone (FSH) and improve the histopathological condition. The potential mechanism might be related to the recombinant C-Raf proto oncogene serine/threonine protein kinase/mitogen-activated protein/extracellular regulated protein kinase (Raf-1/MEK/ERK) signaling pathway. By upregulating the protein expression of the follicle stimulating hormone receptor (FSHR), cyclic adenosine monophosphate (cAMP) and protein kinase A (PKA) inhibited the activation of the downstream Raf-1/MEK/ERK signaling pathway, which in turn inhibited the proliferation of mammary epithelial cells. We analyzed the physicochemical properties of CNCP-A, CNCP-B, and CNCP-C and obtained CNCP-C-I by column chromatographic purification of the best pharmacophore protein CNCP. Using high-performance liquid gel filtration chromatography (HPGFC), we determined the molecular weight of CNCP-C-I and identified it by high-performance liquid tandem mass spectrometry (LC-MS/MS) to obtain the first match for a high confidence protein KRT1. This study provides a theoretical basis for the development of effective traditional Chinese medicines with low toxicity levels for the prevention and treatment of mammary gland diseases.

Progesterone circulation and follicular growth in adapted Bos taurus cows.

The creole breed Blanco Orejinegro (Bos taurus adapted) is an important animal genetic resource in Colombia. However, very little is known about the reproductive physiology of the breed. The objective was to determine the dynamics of progesterone circulation and follicular growth in Blanco Orejinegro cows throughout the estrous cycle. Fifteen cyclic Blanco Orejinegro cows were used and subjected to hormonal protocol for estrous and ovulation synchronization. Once the time of ovulation was identified by monitoring the ovarian dynamics with ultrasonography equipment. For description of the results, the mean was used as a measure of central tendency and the standard error of the mean. Statistical analysis was longitudinal descriptive. Blood samples were collected every 24 hr throughout the estrous cycle for serum quantification of progesterone (P4), monitoring of corpus luteum (CL) growth dynamics and follicular dynamics. It was possible to verify that 76.92% of the Blanco Orejinegro cows presented two follicular waves during the estrous cycle and the highest circulating levels of P4 (> 6.00 ng mL-1) were observed on the 14th day of the estrous cycle. It was concluded that the creole cows of the Blanco Orejinegro breed presented two follicular waves per estrous cycle. In addition to, the size of the CL was consistent with the secretion of progesterone presenting higher circulating levels at the end of the luteal phase.

Placental factors in the development of preterm birth in pregnant women with comorbidity

Premature birth (PB) is a polyetiological problem that depends on many factors, accompanied by violations of the placenta functional competence, changes in its metabolic, hormone-producing and protective functions. The objective: to establish the importance of placental factors in the development of PB in pregnant women with comorbid pathology. Materials and methods. The levels of fetal and placental proteins (placental alfa microglobulin-1, α2-microglobulin of fertility, trophoblastic β1-glycoprotein) and hormones (estriol, placental lactogen, progesterone) were determined in 33 pregnant women with threat of PB at 26–34 weeks of gestation (main group), who had concomitant comorbid pathology in the stage of unstable remission. The control group included 26 healthy pregnant women who were representative for gestational age. Results. In pregnant women with comorbid pathology a decrease of the placenta protein-synthesizing function and the hormone-producing function of the trophoblast was found, which makes it difficult to launch the syntoxic adaptation programs of the mother’s organism, which are responsible for maintaining the pregnancy with the subsequent development of placental dysfunction, the result of which is PB.The markers of these disorders are a 3-fold decrease in the level of trophoblastic β1-glycoprotein (p&lt;0.0001) and a 1.7-fold decrease in the concentration of α2-microglobulin of fertility (p&lt;0.0001) with a simultaneous 4-fold increase of placental alfa microglobulin-1 concentration (p&lt;0.0001) and a decrease in the levels of placental lactogen by 1.6 times (p&lt;0.0001), estradiol by 40 % (p&lt;0.0001) and progesterone by more than 2 times (p&lt;0.0001) compared to healthy pregnant women.Conclusions. In patients with comorbid pathology there are disorders in the secretion of pregnancy proteins due to a decrease in the levels of trophoblastic β1-glycoprotein and α2-microglobulin of fertility and an increase in the level of placental alfa microglobulin-1 and disorders of the hormone-producing function of the trophoblast due to a decrease in the secretion of placental lactogen, progesterone, and estradiol. The disturbance of the secretion of the pregnancy zone proteins and hormones are the early markers for the initiation of premature birth caused by placental dysfunction in pregnant women with comorbid pathology.

Effects of melatonin on development and hormone secretion of sheep theca cells in vitro

Theca cells (TCs) play a unique role in the structure and function of the ovary. They are not only the structural basis of the follicle but also the androgen-secreting cells in female mammals, which can affect the normal development and atresia of the follicle. The results showed that melatonin receptor (MTR) MT1 and MT2 were expressed on sheep TCs. In the present study, the effects of different concentrations of MT at 0, 10−10, 10−8, 10−6 and 10−4 M/L on sheep TCs with regards to the antioxidant levels, proliferation, apoptosis and steroid hormone secretion were investigated. The results showed that in sheep TCs, all concentrations of MT significantly decreased reactive oxygen species (ROS) concentration and BAX expression; increased Cat, Sod1, and BCL-2 expression. The proliferation viability of TCs was significantly inhibited in all groups except for 10−10 M/L MT, and the expression of cyclin D1 and CDK4 was significantly reduced. MT significantly increased StAR expression and progesterone secretion in TCs, but there was no significant effect on androgen secretion and CYP11A1, CYP17A1 and 3β-HSD expression in all groups. MT-induced progesterone secretion was completely inhibited by Luzindole (a nonspecific MT1 and MT2 inhibitor) and partially inhibited by 4p-PDOT (specific MT2 inhibitor). MT-induced progesterone secretion can be inhibited by LY294002 (PI3K/AKT pathway inhibitor). This study indicated that MT inhibits apoptosis and proliferation of in vitro cultured sheep TCs, which has implications for slowing ovarian atresia and aging. MT activates the PI3K/Akt pathway to mediate the synthesis and secretion of progesterone by TCs. This study provides a basis for further exploration of the role of TCs on follicle development and ovarian steroid hormone secretion.

Effects of Intra-Uterine Fluid Accumulation after Artificial Insemination on Luteal Function in Mares

After breeding or artificial insemination, especially with frozen/thawed semen, mares often develop a persistent uterine inflammation, which is diagnosed by intra-uterine fluid accumulation. Here, we explored whether intra-uterine fluid accumulation affects corpus luteum function and tested the hypothesis that intra-uterine fluid accumulation after artificial insemination alters blood flow in the corpus luteum and plasma progesterone concentrations. A total of 40 Standardbred mares were artificially inseminated with frozen-thawed semen 30 to 36 h after induction of ovulation, and cases with or without intra-uterine fluid accumulation were detected by ultrasound 12 h after insemination. Luteal blood flow was measured by Power Doppler ultrasonography 3 and 6 days after ovulation, progesterone concentration was measured in peripheral plasma by ELISA 6 days after ovulation, and pregnancy was diagnosed by ultrasonography 14 days after ovulation. Luteal blood flow increased between 3 and 6 days after ovulation, but blood flow did not differ significantly between cases with (n = 28) and without (n = 25) intra-uterine fluid accumulation after insemination. Surprisingly, progesterone concentrations were higher in cases of intra-uterine fluid accumulation than cases without (9.3 ± 1.1 vs. 6.6 ± 0.5 ng/mL, p = 0.048). Pregnancy was less likely in cases with intra-uterine fluid accumulation than in cases without (10/28 vs. 17/25, p = 0.019), and there was a negative correlation between the severity of intra-uterine fluid accumulation and per cycle pregnancy rate. These data suggest that although intra-uterine fluid accumulation increases the secretion of progesterone, pregnancy is more dependent on uterine health than ovarian function.

Curcuminoids inhibit human and rat placental 3β-hydroxysteroid dehydrogenases: Structure-activity relationship and in silico docking analysis

Ethnopharmacological relevanceIn traditional Chinese medicine, curcuma longa L has been applied to treat pain and tumour-related symptoms for over thousands of years. Curcuminoids, polyphenolic compounds, are the main pharmacological component from the rhizome of Curcuma longa L. Pharmacological investigations have found that curcuminoids have many pharmacological activities of anti-inflammatory, anti-tumour, and anti-metastasis. Aim of the study3β-Hydroxysteroid dehydrogenase (3β-HSD1) catalyses the production of steroid precursors for androgens and estrogens, which play an essential role in cancer metastasis. We explored the potency and mode of action of curcuminoids and their metabolites of inhibiting 3β-HSD1 activity and compared the species difference between human and rat. Materials and methodsIn this study, we investigated the direct inhibition of 6 curcuminoids on human placental 3β-HSD1 activity and compared the species-dependent difference in human 3β-HSD1 and rat placental homolog 3β-HSD4. Results: The inhibitory potency of curcuminoids on human 3β-HSD1 was demethoxycurcumin (IC50, 0.18 μM) > bisdemethoxycurcumin (0.21 μM)>curcumin (2.41 μM)> dihydrocurcumin (4.13 μM)>tetrahydrocurcumin (15.78 μM)>octahydrocurcumin (ineffective at 100 μM). The inhibitory potency of curcuminoids on rat 3β-HSD4 was bisdemethoxycurcumin (3.34 μM)>dihydrocurcumin (5.12 μM)>tetrahydrocurcumin (41.82 μM)>demethoxycurcumin (88.10 μM)>curcumin (137.06 μM)> octahydrocurcumin (ineffective at 100 μM). Human choriocarcinoma JAr cells with curcuminoid treatment showed that these chemicals had similar potency to inhibit progesterone secretion under basal and 8bromo-cAMP stimulated conditions. Docking analysis showed that all chemicals bind pregnenolone-binding site with mixed/competitive mode for 3β-HSD. ConclusionSome curcuminoids are potent human placental 3β-HSD1 inhibitors, possibly being potential drugs to treat prostate cancer and breast cancer.

Redox Status, Estrogen and Progesterone Production by Swine Granulosa Cells Are Impaired by Triclosan.

Triclosan is a chlorinated biphenolic with a broad spectrum of antiseptic activities used in cosmetics and hygiene products. Continuous exposure can lead to absorption and bioaccumulation of this substance with harmful health effects. In fact, previous studies have shown that Triclosan acts as an endocrine-disrupting chemical on reproductive organs, with consequent negative effects on reproductive physiology. Therefore, to assess potential adverse impacts on fertility, we tested Triclosan on swine granulosa cells, a model of endocrine reproductive cells. We examined its effects on the main features of granulosa cell functions such as cell growth (BrdU incorporation and ATP production) and steroidogenesis (17-β estradiol and progesterone secretion). Moreover, since oxidant-antioxidant balance plays a pivotal role in follicular function, redox status markers (superoxide, hydrogen peroxide and nitric oxide production, enzymatic and non-enzymatic scavenging activity) were studied. Our results show that Triclosan significantly inhibits cell growth (p &lt; 0.001), steroidogenesis (p &lt; 0.001), superoxide and nitric oxide production (p &lt; 0.001), while it increases (p &lt; 0.05) enzymatic defense systems. Collectively, these data suggest a disruption of the main granulosa cell functions, i.e., proliferation and hormone production, as well as an imbalance in redox status. On these bases, we can speculate that Triclosan would impair granulosa cell functions, thus exerting negative effects on reproductive function. Further studies are needed to explore lower Triclosan concentrations and to unravel its mechanisms of action at gene level.

Expression and localization of apelin and apelin receptor (APJ) in buffalo ovarian follicles and corpus luteum and the in-vitro effect of apelin on steroidogenesis and survival of granulosa cells

Apelin is an adipose tissue-derived hormone with many physiological functions, including the regulation of female reproduction. It acts through an orphan G protein-coupled receptor APJ/APLNR. The present study aimed to investigate the expression of apelin and its receptor APJ in the ovarian follicles and corpus luteum (CL) and the role of apelin on steroidogenesis and cell survival. Ovarian follicles were classified into four groups based on size and estradiol (E2) level in the follicular fluid as follows: (i) F1 (4–6 mm; <0.5 ng/mL) (ii) F2 (7–9 mm; 0.5–5 ng/mL) (iii) F3 (10–13 mm; 5–40 ng/mL) and (iv) F4 (dominant/pre-ovulatory follicle) (>13 mm; >180 ng/mL). The corpora lutea (CL) were categorized into early (CL1), mid (CL2), late luteal (CL3), and regressing (CL4) CL stages. Expression of apelin increased with follicle size, with significantly greatest in the dominant or pre-ovulatory follicle (P < 0.05). Expression of APJ was greater in large and dominant follicles than in small and medium follicles (P < 0.05). In CL, the mRNA and protein abundance of apelin and apelin receptor was greater during mid (CL2) and late luteal (CL3) stages as compared to early (CL1) and regressing (CL4) stages (P < 0.05). Both the factors were localized in granulosa and theca cells of follicles and small and large luteal cells of CL. The pattern of the intensity of immunofluorescence was similar to mRNA and protein expression. Granulosa cells were cultured in vitro and treated at 1, 10, and 10 ng/mL apelin-13 either alone or in the presence of the follicle-stimulating hormone (FSH) (30 ng/mL) or insulin-like growth factor-I (IGF-I) (10 ng/mL) for 48 h. The luteal cells were treated with apelin-13 at 1, 10, and 100 ng/mL doses for 48 h. Apelin treatment at 10 and 100 ng/ml significantly (P < 0.05) increased E2 secretion, cytochrome P450 aromatase or CYP19A1 expression in GC. In luteal cells, apelin at 10 ng/mL and 100 ng/mL significantly (P < 0.05) increased progesterone (P4) secretion and HSD3B1 expression. In GCs, apelin, either alone or in combination, increased PCNA expression and inhibited CASPASE3 expression suggesting its role in cell survival. In conclusion, this study provides novel evidence for the presence of apelin and receptor APJ in ovarian follicles and corpora lutea and the stimulatory effect on E2 and P4 production and promotes GC survival in buffalo, suggesting the role of apelin in follicular and luteal functions in buffalo.

Human ovarian follicular granulosa cells isolated during ART procedure reflect substantial changes in activation of hormonal signaling pathways, during long-term in vitro conditions

Abstract The ovary is commonly known as an endocrine gland responsible for sex steroid production. One of the outstanding cells in ovarian microenvironment - granulosa cells (GCs) are responsible for converting the androgens to estrogens during follicular growth and secreting progesterone after ovulation. These secretory processes within the ovary are directly involved in hormonal signaling pathways, and they depend on different stages of cholesterol and lipid biosynthesis during the ovarian cycle. The understating of the regulation and further investigation into the processes taking part in ovary will expose new clinical advantages in detection and treatment of female reproductive system diseases associated with sex hormone abnormalities. The expression of genes belonging to ontology groups associated with steroid biosynthesis and metabolism, such as “cholesterol biosynthetic process” (GO:0006695, “regulation of lipid biosynthetic process” (GO:0046890), “regulation of lipid metabolic process” (GO:0019216), “response to insulin” (GO:0032868) and “response to lipopolysaccharide” (GO:0032496) were analyzed by using the microarray approach. The patterns of gene expression in human GCs at days 1-day, 7-day, 15-day, and 30-day of primary in vitro culture have been analyzed. Based on the microarray results, a group of upregulated genes have been selected: CCL20, CXCL5, STAR, MSMO1, and AADAC. The genes STAT5B, OPA3, PPARG, PROX1, and SEC14L2 were decreased across all the experimental groups during the 30-day cell cultivation period. These results suggest that, the GCs in cell culture under in vitro express steroidogenic markers and it is important to understand associations with lipid and liposaccharide synthesis relative to reproductive medicine.

MELATONIN AND MISCARRIAGE

Spontaneous abortions (abortion up to 22 weeks of gestation since the last menstrual cycle or with a fetal weight of less than 500.0 g) occur in 15-20% of the total number of registered pregnancies. The incidence of miscarriages increases up to 15% in women under 25 and to 35% and more in women over 38. Causes of miscarriages can be divided into two categories: those which associated with chromosomal abnormalities and those which associated with disruption of the intrauterine environment.Some studies have shown the infl uence of systematic and placental oxidative stress in the pathophysiology of abortion and repeated «stop» of pregnancy. Lack of antioxidant protection leads to recurrent abortions. Membranes’ damages with the production of lipid peroxides, which are induced by reactive oxygen species (ROS), as well as due to certain disorders or disorganization, immediately cause abortion. There are versions that pineal insuffi ciency may be associated with spontaneous abortions, even in cases where there are no chromosomal abnormalities and structural disorders of the uterus. This hypothesis is based on the fact that melatonin is a strong antioxidant which binds free radicals and its concentration normally increases signifi cantly during pregnancy and in pinealectomy rats the frequency of miscarriages increases. Melatonin has an immunomodulatory eff ect. It stimulates the secretion of progesterone, which reduces the degree of uterine contraction and prevents immunological rejection of the trophoblast, inhibits the synthesis of prostaglandins, which can potentially induce uterine contractions. Pinealectomy leads to a signifi cant reduction of circulating in blood melatonin level and to abortion in rats.

Low plasma progesterone concentration during the early luteal phase delays endometrial development and the beginning of placentation in mares

While detrimental effects of reduced plasma progesterone concentration in the early luteal phase on conceptus development in horses have recently been demonstrated, there is no information on associated effects on the endometrium, allantochorion (AC), and chorionic girdle (CG) in this species. We hypothesised that reduced early postovulatory progesterone concentration in pregnant horses is detrimental to endometrial function and development of the embryonic membranes and is an underlying cause of delayed conceptus development. After insemination and ovulation, mares (n = 11) were assigned to treatment (TREAT) or control (CON) during two pregnancies. In TREAT pregnancies, mares received a PGF2α analogue for four consecutive days starting on the day of ovulation with the aim to reduce progesterone secretion. Mares were left untreated in CON pregnancies and thus served as their own controls. Endometrial biopsies for analysis of histomorphology, epidermal growth factor (EGF) and EGF receptor (EGFR) mRNA and protein expression in the endometrium, AC, and CG as well as abundance of regulatory T lymphocytes (Tregs) were collected on day 34 of pregnancy. Histomorphometric analysis revealed a higher luminal endometrium and a higher CG epithelium in CON compared to TREAT pregnancies. Abundance of mRNA for EGF and EGFR was large in the endometrium, AC and CG but did not differ between TREAT and CON pregnancies. The number of endometrial regulatory T lymphocytes was reduced in TREAT compared to CON pregnancies, adding further aspects to the potentially detrimental effects of reduced progesterone concentrations on equine pregnancy.

ODP417 Kisspeptin directly stimulates estrogen and progesterone secretion from human granulosa cells.

Abstract Kisspeptin is a peptide hormone that has a central role to stimulate gonadotropin-releasing hormone secretion from the hypothalamus. Furthermore, it was shown to have peripheral roles on enhancing CYP19 (aromatase) expression and aromatase secretion from human granulosa cells (1). The objectives of this study were to determine direct effects of kisspeptin treatment on estrogen and progesterone secretion from human granulosa-like tumor cell line (KGN). KGN cells (n=3) were treated with 10 nM follicle stimulating hormone (FSH); 100, 1,000, and 10,000 nM kisspeptin; and FSH together with different doses of kisspeptin for 24 hours. Estrogen and progesterone concentrations in supernatant were measured by enzyme immunoassay kits. The results showed that FSH treatment alone (P&amp;lt;0. 05) and FSH together with 100 (P&amp;lt;0. 01), 1,000 (P&amp;lt;0. 001), and 10,000 (P&amp;lt;0. 001) nM kisspeptin increased estrogen concentrations in supernatants when compared to control. Kisspeptin treatment alone did not increase estrogen concentrations in supernatant when compared to control. Interestingly, kisspeptin treatment at 1,000 (P&amp;lt;0. 01) and 10,000 (P&amp;lt;0. 01) nM together with FSH enhanced estrogen concentrations in supernatant when compared to FSH treatment alone. Furthermore, FSH treatment alone (P&amp;lt;0. 05) and FSH together with kisspeptin at doses of 1,000 (P&amp;lt;0. 001) and 10,000 (P&amp;lt;0. 05) nM increased progesterone concentrations in supernatant when compared to control. All doses of kisspeptin did not increase progesterone concentrations in supernatant when compared to control. Only 1,000 nM kisspeptin together with FSH enhanced progesterone secretion in supernatant when compared to FSH alone (P&amp;lt;0. 01). Taken together, FSH stimulated estrogen and progesterone secretion from human granulosa cells and kisspeptin enhanced these effects in addition to the effects of FSH alone. Further studies are required to determine whether kisspeptin treatment can restore the functions of unresponsive or partially responsive granulosa cells of aging humans to secrete estrogen and progesterone as well as kisspeptin is useful in augmenting infertility treatment. Reference: (1) Qin L, Sitticharoon C, Petyim S, Keadkraichaiwat I, Sririwichitchai R, Maikeaw P, et al. Exp Biol Med (Maywood). 2021;246(8): 996-1010. Presentation: No date and time listed