Human corpus luteum physiology and the luteal-phase dysfunction associated with ovarian stimulation

Follicle stimulating hormone controls granulosa cell glutamine synthesis to regulate ovulation

Polycystic ovary syndrome (PCOS) is the leading cause of anovulatory infertility. Inadequate understanding of the ovulation drivers hinders PCOS intervention. Herein, we report that follicle stimulating hormone (FSH) controls follicular fluid (FF) glutamine levels to determine ovulation. Murine ovulation starts from FF-exposing granulosa cell (GC) apoptosis. FF glutamine, which decreases in pre-ovulation porcine FF, elevates in PCOS patients FF. High-glutamine chow to elevate FF glutamine inhibits mouse GC apoptosis and induces hormonal, metabolic, and morphologic PCOS traits. Mechanistically, follicle-development-driving FSH promotes GC glutamine synthesis to elevate FF glutamine, which maintain follicle wall integrity by inhibiting GC apoptosis through inactivating ASK1-JNK apoptotic pathway. FSH and glutamine inhibit the rapture of cultured murine follicles. Glutamine removal or ASK1-JNK pathway activation with metformin or AT-101 reversed PCOS traits in PCOS models that are induced with either glutamine or EsR1-KO. These suggest that glutamine, FSH, and ASK1-JNK pathway are targetable to alleviate PCOS.

In vitro effect of visfatin on endocrine functions of the porcine corpus luteum

Previously, we demonstrated the expression of visfatin in porcine reproductive tissues and its effect on pituitary endocrinology. The objective of this study was to examine the visfatin effect on the secretion of steroid (P4, E2) and prostaglandin (PGE2, PGF2α), the mRNA and protein abundance of steroidogenic markers (STAR, CYP11A1, HSD3B, CYP19A1), prostaglandin receptors (PTGER2, PTGFR), insulin receptor (INSR), and activity of kinases (MAPK/ERK1/2, AKT, AMPK) in the porcine corpus luteum. We noted that the visfatin effect strongly depends on the phase of the estrous cycle: on days 2-3 and 14-16 it reduced P4, while on days 10-12 it stimulated P4. Visfatin increased secretion of E2 on days 2-3, PGE2 on days 2-3 and 10-12, reduced PGF2α release on days 14-16, as well as stimulated the expression of steroidogenic markers on days 10-12 of the estrous cycle. Moreover, visfatin elevated PTGER mRNA expression and decreased its protein level, while we noted the opposite changes for PTGFR. Additionally, visfatin activated ERK1/2, AKT, and AMPK, while reduced INSR phosphorylation. Interestingly, after inhibition of INSR and signalling pathways visfatin action was abolished. These findings suggest a regulatory role of visfatin in the porcine corpus luteum.

Dynamic transcriptome analysis of Maiwa yak corpus luteum during the estrous cycle

Maiwa yak is a special breed of animal living on the Qinghai-Tibet Plateau, which has great economic value, but its fertility rate is low. The corpus luteum (CL) is a temporary tissue that plays a crucial role in maintaining the physiological cycle. However, little is known about the transcriptome profile in Maiwa yak CL. In the present study, the transcriptome of Maiwa yak CL at early (EYCL), middle (MYCL) and late-stages (LYCL) was studied employing high-throughput sequencing. A total of 25,922 transcripts were identified, including 22,277 known as well as 3,645 novel ones. Furthermore, 690 and 212 differentially expressed (DE) mRNAs were detected in the EYCL vs. MYCL and MYCL vs. LYCL groups, respectively. KEGG pathway enrichment analysis of DEGs illustrated that the most enriched pathway was PI3K-Akt pathway. Furthermore, twenty-six DEGs were totally found to be associated with different biological processes of CL development. One of these genes, PGRMC1, displayed a dynamical expression trend during the lifespan of yak CL. The knockdown of PGRMC1 in luteinized yak granulosa cells resulted in defective steroidogenesis. In conclusion, this study analyzed the transcriptome profiles in yak CL of different stages, and provided a novel database for analyzing the gene network in yak CL.HIGHLIGHTSThe manuscript analyzed the transcriptome profiles in yak CL during the estrous cycle.Twenty-six DEGs were found to be associated with the development or function of CL.One of the DEGs, PGRMC1, was found to be responsible for steroidogenesis in luteinized yak granulosa cells.

Adropin may regulate corpus luteum formation and its function in adult mouse ovary

BACKGROUND

Adropin, a unique peptide hormone, has been associated with the regulation of several physiological processes, including glucose homeostasis, fatty acid metabolism, and neovascularization. However, its possible role in ovarian function is not understood. Our objective was to examine the expression of adropin and its putative receptor, GPR19, in the ovaries of mice at various phases of the estrous cycle.

METHODS

Immunohistochemistry and western blot analysis were performed to explore the localization and changes in expression of adropin and GPR19 in the ovaries during different phases of the estrous cycle in mice. Hormonal assays were performed with ELISA. An in vitro study was performed to examine the direct effect of adropin (10, 100 ng/ml) on ovarian function.

RESULTS

A western blot study showed that adropin and GPR19 proteins were maximum during the estrus phase of the estrous cycle. Interestingly, adropin and GPR19 displayed intense immunoreactivity in granulosa cells of large antral follicles and corpus luteum. This suggested the possible involvement of adropin in corpus luteum formation. Adropin treatment stimulated progesterone synthesis by increasing GPR19, StAR, CYP11A1, and 3β-HSD expressions, while it decreased estrogen synthesis by inhibiting 17β-HSD and aromatase protein expressions. Moreover, adropin treatment upregulated the cell cycle arrest-CDK inhibitor 1B (p27kip1), pERK1/2, and angiogenic protein (EG VEGF) that are involved in the process of luteinization.

CONCLUSIONS

Adropin GPR19 signaling promotes the synthesis of progesterone and upregulates the expression of p27kip1, EG VEGF, and erk1/2, resulting in cell cycle arrest and neovascularization, which ultimately leads to corpus luteum formation.

In vitro effects of PPAR gamma ligands on gene expression in corpus luteum explants in non-pregnant pigs - Transcriptome analysis

The corpus luteum (CL) is a temporary endocrine structure in the female ovaries that develops cyclically in mature females during luteinization. This study aimed to determine the in vitro effects of peroxisome proliferator-activated receptor gamma (PPARγ) ligands on the transcriptomic profile of the porcine CL in the mid- and late-luteal phase of the estrous cycle using RNA-seq technology. The CL slices were incubated in the presence of PPARγ agonist - pioglitazone or antagonist - T0070907. We identified 40 differentially expressed genes after treatment with pioglitazone and 40 after treatment with T0070907 in the mid-luteal phase as well as 26 after pioglitazone and 29 after T0070907 treatment in the late-luteal phase of the estrous cycle. In addition, we detected differences in gene expression between the mid- and late-luteal phase without treatment (409 differentially expressed genes). This study revealed a number of novel candidate genes that may play a role in controlling the function of CL by regulating signaling pathways related to ovarian steroidogenesis, metabolic processes, cell differentiation, apoptosis, and immune responses. These findings become a basis for further studies to explain the mechanism of PPARγ action in the reproductive system.

Identification of microRNA transcriptome throughout the lifespan of yak (Bos grunniens) corpus luteum

The corpus luteum (CL) is a temporary organ that plays a critical role for female fertility by maintaining the estrous cycle. MicroRNA (miRNA) is a class of non-coding RNAs involved in various biological processes. However, there exists limited knowledge of the role of miRNA in yak CL. In this study, we used high-throughput sequencing to study the transcriptome dynamics of miRNA in yak early (eCL), middle (mCL) and late-stage CL (lCL). A total of 6,730 miRNAs were identified, including 5,766 known and 964 novels miRNAs. Three miRNAs, including bta-miR-126-3p, bta-miR-143 and bta-miR-148a, exhibited the highest expressions in yak CLs of all the three stages. Most of the miRNAs were 20-24 nt in length and the peak was at 22 nt. Besides, most miRNAs with different lengths displayed significant uracil preference at the 5'-end. Furthermore, 1,067, 280 and 112 differentially expressed (DE) miRNAs were found in eCL vs. mCL, mCL vs. lCL, and eCL vs. lCL, respectively. Most of the DE miRNAs were down-regulated in the eCL vs. mCL and eCL vs. lCL groups, and up-regulated in the mCL vs. lCL group. A total of 18,904 target genes were identified, with 18,843 annotated. Pathway enrichment analysis of the DE miRNAs target genes illustrated that the most enriched cellular process in each group included pathways in cancer, PI3K-Akt pathway, endocytosis, and focal adhesion. A total of 20 putative target genes in 47 DE miRNAs were identified to be closely associated with the formation, function or regression of CL. Three DE miRNAs, including bta-miR-11972, novel-miR-619 and novel-miR-153, were proved to directly bind to the 3'-UTR of their predicated target mRNAs, including CDK4, HSD17B1 and MAP1LC3C, respectively. Both of these DE miRNAs and their target mRNAs exhibited dynamic expression profiles across the lifespan of yak CL. This study presents a general basis for understanding of the regulation of miRNA on yak CL and also provides a novel genetic resource for future analysis of the gene network during the estrous cycle in the yak.

Elevated non-essential metals and the disordered metabolism of essential metals are associated to abnormal pregnancy with spontaneous abortion

Spontaneous abortion is a considerable threat to the physiology and mental health of the mother. The etiology of spontaneous abortion is multifactorial with complicated mechanisms, of which overexposure to non-essential metals (especially heavy metals) has been proposed to be associated with adverse birth outcomes. However, significant knowledge gaps remain to be filled in, such as the deleterious profile of non-essential metals and their interplay with essential metals in abnormal pregnancy. Under this setting, we aimed to address these challenges by conducting a cross-sectional study on 56 patients with spontaneous abortion in the 1^st trimester, by comparing to 55 healthy pregnant women in 1^st the trimester and 41 non-pregnant healthy women. Overexposure to a few non-essential metals, such as arsenic (As), antimony (Sb) and bismuth (Bi), was found in patients with spontaneous abortion, and likewise, some essential elements, such as magnesium (Mg), copper (Cu), vanadium (V), strontium (Sr) and tin (Sn), were also found to be elevated under spontaneous abortion. Further evidence of abnormal pregnancy was induced by a reduced level of internal hormones necessary for normal gestation, such as estradiol (E2) and progesterone (PRGE) in women with spontaneous abortion. Lactate dehydrogenase (LDH) and thyroid-stimulating hormone (TSH) levels were slightly increased in patients with spontaneous abortion. Comprehensive correlation analyses were carried out to identify the crucial factors that result in abortion. Our data stratified the important variables in decreasing order: PRGE, As, Mg, Sb, Sr, Sn, Bi and pregnant times in the progress of spontaneous abortion. Moreover, labyrinthine associations were uncovered between PRGE, non-essential metals and essential elements in causing spontaneous abortion. Therefore, our combined data unveiled the likely synergistic implications of elevated non-essential metals and the disordered metabolism of essential metals in abnormal pregnancy.

Luteal phase support in fresh and frozen embryo transfer cycles

Nearly 5 million babies have been delivered following assisted conception (IVF/ICSI) and the demand is increasing. Meticulous ovarian stimulation and well programmed luteal phase support are the landmarks of treatment success. Although the importance of luteal phase support in IVF/ICSI cycles is well established, the optimal route, dose and duration of this support is still a matter of debate. Regardless of the ovarian stimulation, parenteral and vaginal progesterone has been one of the most common routes. However, oral or subcutaneous routes are also well-investigated and reveal satisfactory clinical outcomes. It is obviously critical to choose a progesterone with adequate clinical efficacy and patient tolerability as well. Moreover, fresh and frozen embryo transfer cycles markedly different from each other in terms of physiological changes and luteal support concept should be modified accordingly. The aim of this narrative review is to provide evidence-based take home messages for the luteal phase support in either fresh or frozen embryo transfer cycles in the context of a recent scientific evidence.

Higher ꞵ-human chorionic gonadotropin and estrogen levels during the first 6 weeks of pregnancy are associated with threatened abortion

The associations of human chorionic gonadotropin (hCG), estrogen, and progesterone levels with threatened abortion have not been fully studied. Eighty women with threatened abortion were recruited sequentially, and the levels in their pregnancy hormones during the first trimester were compared with that of 160 normal early pregnancy controls. The natural logarithm transformed (Ln) hCG and Lnestrogen of women with threatened abortion and gestational age ≤ 6 weeks were significantly higher than values for the normal controls of the same gestational age (8.6 ± 1.2 vs. 7.4 ± 1.7 mIU/mL and 5.8 ± 0.4 vs. 5.4 ± 0.5 pg/mL); the two hormones reached similar levels in the groups of gestational age > 6 weeks. Among the group with gestational age ≤ 6 weeks, a univariate logistic regression showed that LnhCG and Lnestrogen were associated with threatened abortion, with odds ratios (ORs) of 1.85 [95% confidence interval (CI): 1.30-2.64] and 4.62 (95% CI: 1.67-12.80), respectively. The multivariate logistic regression model revealed that hCG and estrogen were mutually confounding factors, and only hCG was an independent factor for threatened abortion (OR 1.56; 95% CI: 1.06-2.28). None of the variables in the univariate or multivariate logistic regression was a factor associated with threatened abortion after 6 weeks gestational age. In conclusion, β-hCG and estrogen levels in the first half of the first trimester are factors associated with threatened abortion.

Necroptosis in primate luteolysis: a role for ceramide

The corpus luteum (CL) is a transient endocrine organ, yet molecular mechanisms resulting in its demise are not well known. The presence of phosphorylated mixed lineage kinase domain-like pseudokinase pMLKL(T357/S358) in human and nonhuman primate CL samples (Macaca mulatta and Callithrix jacchus) implied that necroptosis of luteal cells may be involved. In M. mulatta CL, pMLKL positive staining became detectable only from the mid-late luteal phase onwards, pointing to necroptosis during regression of the CL. Cell death, including necroptosis, was previously observed in cultures of human luteal granulosa cells (GCs), an apt model for the study of the human CL. To explore mechanisms of necroptotic cell death in GCs during culture, we performed a proteomic analysis. The levels of 50 proteins were significantly altered after 5 days of culture. Interconnectivity analysis and immunocytochemistry implicated specifically the ceramide salvage pathway to be enhanced. M. mulatta CL transcriptome analysis indicated in vivo relevance. Perturbing endogenous ceramide generation by fumonisin B1 (FB1) and addition of soluble ceramide (C2-CER) yielded opposite actions on viability of GCs and therefore supported the significance of the ceramide pathway. Morphological changes indicated necrotic cell death in the C2-CER treated group. Studies with the pan caspase blocker zVAD-fmk or the necroptosis blocker necrosulfonamid (NSA) further supported that C2-CER induced necroptosis. Our data pinpoint necroptosis in a physiological process, namely CL regression. This raises the possibility that the primate CL could be rescued by pharmacological inhibition of necroptosis or by interaction with ceramide metabolism.

The role of Natural Cycle IVF in assisted reproduction

Natural Cycle IVF (NC-IVF) with and without modifications is being increasingly performed. NC-IVF and conventional gonadotropin-stimulated IVF (cIVF) should not be understood as competing treatments, but as complementary treatments with different target groups and to some extent other indications. NC-IVF is particularly interesting for couples who wish to save money, wish a treatment with as few risks as possible and for women who would like to avoid selection and cryopreservation of embryos. NC-IVF therefore contributes to the concept of individualized and patient-oriented therapy. The time to pregnancy is slightly longer than with conventional IVF. NC-IVF is particularly suitable for younger women and for women with a very low ovarian reserve. In this article, the principles of NC-IVF, i.e. monofollicular IVF without gonadotropin stimulation, are described and the technical differences to cIVF, advantages and disadvantages, perinatal outcome and indications for NC-IVF are highlightened.

Analysis of two different luteal phase support regimes and evaluation of in vitro fertilization-intra cytoplasmic sperm injection outcomes

Objective:

To evaluate clinical pregnancy rates, miscarriage rates, ongoing pregnancy rates, and in vitro fertilization-intra cytoplasmic sperm injection outcomes of gonadotropin releasing hormone agonist (GnRHa) administration compared with human chorionic gonadotropin (hCG) application for luteal phase support.

Materials and Methods:

A total of 456 patients were included in the study. The patients were divided into two groups according to luteal phase support type: in group 1 (n=158), single-dose triptorelin acetate 0.1 mg was given on the sixth day after the oocyte pick-up (OPU). In group 2 (n=298), hCG 1500 IU was given on day 4, 7 and 10 after the OPU.

Results:

Both groups were homogeneous in relation with age and antral follicle count. The number of stimulation days and endometrial thickness on hCG day (mm) were found to be significantly higher in group 2 than in group 1 (p<0.001). The clinical pregnancy rate was slightly higher in the GnRHa group, but this difference was not statistically significant.

Conclusion:

Although there was no statistically significant difference between the two groups, luteal phase support with single-dose GnRHa might be as efficient as three doses of hCG. Large prospective, randomized-controlled studies are required comparing GnRHa and hCG for luteal phase support.

Systematic Review of Ovarian Activity and Potential for Embryo Formation and Loss during the Use of Hormonal Contraception

The purpose of this review was to determine whether there is evidence that ovulation can occur in women using hormonal contraceptives and whether these drugs might inhibit implantation. We performed a systematic review of the published English-language literature from 1990 to the present which included studies on the hormonal milieu following egg release in women using any hormonal contraceptive method. High circulating estrogens and progestins in the follicular phase appear to induce dysfunctional ovulation, where follicular rupture occurs but is followed by low or absent corpus luteum production of progesterone. Hoogland scoring of ovulatory activity may inadvertently obscure the reality of ovum release by limiting the term "ovulation" to those instances where follicular rupture is followed by production of a threshold level of luteal progesterone, sufficient to sustain fertilization, implantation, and the end point of a positive β-human chorionic gonadotropin. However, follicular ruptures and egg release with subsequent low progesterone output have been documented in women using hormonal contraception. In the absence of specific ovulation and fertilization markers, follicular rupture should be considered the best marker for egg release and potential fertilization. Women using hormonal contraceptives may produce more eggs than previously described by established criteria; moreover, suboptimal luteal progesterone production may be more likely than previously acknowledged, which may contribute to embryo loss. This information should be included in informed consent for women who are considering the use of hormonal contraception.

Summary

For this study, the authors looked at English-language research articles that focused on how hormonal birth control, such as the birth control pill, may affect very early human embryos. The authors found that abnormal ovulation, or release of an egg followed by abnormal hormone levels, may often occur in women using hormonal birth control. This may increase the number of very early human embryos who are lost before a pregnancy test becomes positive. For women who are thinking about using hormonal birth control, this is important information to consider.

Action of the hydroethanolic extract of the flowers of Acmella oleracea (L.) R.K. Jansen on the reproductive performance of Wistar females rats: A popular female aphrodisiac from the Amazon

ETHNOPHARMACOLOGICAL RELEVANCE

The species Acmella oleracea (L.) R.K. Jansen (Asteraceae), popularly known as jambú, is marketed in fairs as a female aphrodisiac and has several pharmacological activities already confirmed, among them the sexual stimulant action. The objective of this study was to evaluate the effects of the oral administration of the hydroethanolic extract of A. oleracea flowers (EHAo) on wistar rats during the pre-mating, mating, and pre-implantation period.

MATERIAL AND METHODS

During the treatment period, measurements of feed intake, water intake, weight, estrous cycle, behavior, reproductive parameters, biochemical parameters, hematological parameters, and histopathology of ovaries were performed daily.

RESULTS

In the gas chromatography analysis - mass spectrometry characterization, the compound (2E, 6Z, 8E) -N-isobutyldeca-2,6,8-trienamide (spilanthol) was detected as the majority compound at the 84% concentration. In the conditions of this study, EHAo did not cause maternal toxicity. However, in the estrous cycle, the frequency of the Proestrous (P) and Estrous (E) phase was significantly increased with the doses of 88.91 and 444.57mg/kg of the EHAo in relation to the control. On the other hand, the metaestrous (M) and diestrous (D) phases showed a significant reduction in their frequency in the groups treated with EHAo. Water intake increased significantly (p < 0.01), as well as the triglyceride levels, the total cholesterol and fractions (p < 0.05), and the percentage of neutrophils (p < 0.05).

CONCLUSION

It is concluded, therefore, that the treatment with EHAo, which is one of the forms popularly used, is safe in the concentrations and time of treatment studied as it is able to influence the estrous cycle without altering folliculogenesis and fertility.

The significance of estradiol metabolites in human corpus luteum physiology

The human corpus luteum (CL) is a temporary endocrine gland derived from the ovulated follicle. Its formation and limited lifespan is critical for steroid hormone production required to support menstrual cyclicity, endometrial receptivity for successful implantation, and the maintenance of early pregnancy. Endocrine and paracrine-autocrine molecular mechanisms associated with progesterone production throughout the luteal phase are critical for the development, maintenance, regression, and rescue by hCG which sustains CL function into early pregnancy. However, the signaling systems driving the regression of the primate corpus luteum in non-conception cycles are not well understood. Recently, there has been interest in the functional roles of estradiol metabolites (EMs), mostly in estrogen-producing tissues. The human CL produces a number of EMs, and it has been postulated that the EMs acting via paracrine-autocrine pathways affect angiogenesis or LH-mediated events. The present review describes advances in understanding the role of EMs in the functional lifespan and regression of the human CL in non-conception cycles.

Progesterone in normal and pathological pregnancy

Progesterone is an essential hormone in the process of reproduction. It is involved in the menstrual cycle, implantation and is essential for pregnancy maintenance. It has been proposed and extensively used in the treatment of different gynecological pathologies as well as in assisted reproductive technologies and in the maintenance of pregnancy. Called "the pregnancy hormone", natural progesterone is essential before pregnancy and has a crucial role in its maintenance based on different mechanisms such as: modulation of maternal immune response and suppression of inflammatory response (the presence of progesterone and its interaction with progesterone receptors at the decidua level appears to play a major role in the maternal defense strategy), reduction of uterine contractility (adequate progesterone concentrations in myometrium are able to counteract prostaglandin stimulatory activity as well as oxytocin), improvement of utero-placental circulation and luteal phase support (it has been demonstrated that progesterone may promote the invasion of extravillous trophoblasts to the decidua by inhibiting apoptosis of extravillous trophoblasts). Once the therapeutic need of progesterone is established, the key factor is the decision of the best route to administer the hormone and the optimal dosage determination. Progesterone can be administered by many different routes, but the most utilized are oral, the vaginal and intramuscular administration. The main uses of progesterone are represented by: threatened miscarriage, recurrent miscarriage and preterm birth (in the prevention strategy, as a tocolytic agent and also in the maintenance of uterine quiescence).

Activin A upregulates PTGS2 expression and increases PGE2 production in human granulosa-lutein cells

Activin A is one of the members of transforming growth factor-β superfamily that is expressed in human large luteal cells, and may act in an autocrine/paracrine manner to regulate luteal function. Prostaglandin-endoperoxide synthase 2 (PTGS2) enzyme and its derivative, prostaglandin E2 (PGE2), play significant roles in the regulation of corpus luteum formation and maintenance. To date, whether activin A can induce the expression of PTGS2 and the production of PGE2 in human granulosa-lutein cells is largely unknown. The aim of this study was to examine the effects of activin A on the regulation of PTGS2 expression and PGE2 production in human granulosa-lutein cells, and to investigate the underlying signal transduction mechanisms. In this study, the immortalized (SVOG cells) and primary human granulosa-lutein cells were used as the cell models. A TGF-β/activin type I receptor inhibitor, SB431542 and small interfering RNAs were used to investigate the activin A-induced downstream signaling pathway. We have demonstrated that activin A upregulated the expression of PTGS2 and increased the production of PGE2 via an ACVR1B-mediated SMAD2/3–SMAD4 signaling pathway. Our results suggest that activin A may be involved in the modulation of human corpus luteum formation via the induction of PTGS2 expression and PGE2 production.

Lipid droplets in cultured luteal cells in non-pregnant sheep fed different planes of nutrition

Accumulation of lipid droplets (LD) in luteal cells likely is important for energy storage and steroidogenesis in the highly metabolically active corpus luteum (CL). The objective of this study was to determine the effect of plane of nutrition on progesterone (P4) secretion, and lipid droplet number and size in cultured ovine luteal cells. Ewes were randomly assigned to one of three nutritional groups: control (C; 100% NRC requirements, n=9), overfed (O; 2×C, n=12), or underfed (U; 0.6×C, n=10). Superovulation was induced by follicle stimulating hormone injections. At the early and mid-luteal phases of the estrous cycle, CL were dissected from ovaries, and luteal cells isolated enzymatically. Luteal cells were incubated overnight in medium containing serum in chamber slides. Media were then changed to serum-free and after 24h incubation, media were collected for P4 analysis, and cells were fixed in formalin and stained with BODIPY followed by DAPI staining. Z-stacks of optical sections of large and small luteal cells (LLC and SLC, respectively) were obtained using a laser-scanning microscope. Rendered 3D images of individual LLC and SLC were analyzed for cell volume, and total and individual LD volume, number and percentage of cellular volume occupied by LD by using Imaris software. Concentrations of P4 in serum and media were greater (P<0.05) at the mid than early-luteal phase, and were not affected by nutritional plane. LD total volume and number were greater (P<0.001) in LLC than SLC; however, mean volume of individual LD was greater (P<0.02) in SLC than LLC. In LLC, total LD volume was greater (P<0.02) in O than C and U ewes. In SLC, total LD volume and number was greater (P<0.003) at the mid than early-luteal phase, and percentage of cell volume occupied by LD was greater (P<0.002) in U than C and O ewes. These data demonstrate that both stage of luteal development and nutritional plane affect selected LD measurements and thus may affect luteal functions. Furthermore, these data confirm that LD dynamics differ among parenchymal steroidogenic luteal cell types.

Physiological Aspects of Female Fertility: Role of the Environment, Modern Lifestyle, and Genetics

Across the Western World there is an increasing trend to postpone childbearing. Consequently, the negative influence of age on oocyte quality may lead to a difficulty in conceiving for many couples. Furthermore, lifestyle factors may exacerbate a couple's difficulty in conceiving due mainly to the metabolic influence of obesity; however, the negative impacts of low peripheral body fat, excessive exercise, the increasing prevalence of sexually transmitted diseases, and smoking all have significant negative effects on fertility. Other factors that impede conception are the perceived increasing prevalence of the polycystic ovary syndrome, which is further exacerbated by obesity, and the presence of uterine fibroids and endometriosis (a progressive pelvic inflammatory disorder) which are more prevalent in older women. A tendency for an earlier sexual debut and to have more sexual partners has led to an increase in sexually transmitted diseases. In addition, there are several genetic influences that may limit the number of oocytes within the ovary; consequently, by postponing attempts at childbearing, a limitation of oocyte number may become evident, whereas in previous generations with earlier conception this potentially reduced reproductive life span did not manifest in infertility. Environmental influences on reproduction are under increasing scrutiny. Although firm evidence is lacking however, dioxin exposure may be linked to endometriosis, phthalate exposure may influence ovarian reserve, and bisphenol A may interfere with oocyte development and maturation. However, chemotherapy or radiotherapy is recognized to lead to ovarian damage and predispose the woman to ovarian failure.

Segmented ART - The new era in ART?

Currently up to 4% of infants born in developing countries are conceived through assisted reproductive technology (ART). Even though most of these conceptions occur and progress without complications, ART procedures and processes may increase iatrogenesis through complications in - and after conception. We herein review and discuss the clinically and scientific implications and evidence of iatrogenesis, and show how the evolution in ART technologies and procedures has led to the current presumption that frozen embryo transfer might be a more optimal strategy than fresh embryo transfer, in terms of not only reproduction, but also of maternal and fetal outcomes. There is increasing scientific evidence to support the notion that controlled ovarian stimulation could induce significant changes to the endocrine profile of a reproductive cycle, especially to the reproductively important early luteal phase. These changes may not only have a negative effect on implantation and early placentation, but also on the mother, the fetus, and the infant. The overt consequences of controlled ovarian stimulation include ovarian hyperstimulation syndrome, reduced embryo implantation, increased ectopic pregnancy, and altered placentation and fetal growth. The cumulative scientific evidence from this review suggests that GnRHa trigger in segmented ART might constitute the future routine treatment regimen for IVF patients, providing a safe, effective, and patient friendly treatment.

Application of gel-based proteomic technique in female reproductive investigations

Recently, gel-based proteomics has been increasingly applied to investigate proteins involved in female reproductive tract in healthy and disease states. Gel-based proteomics coupled by mass spectrometry (MS) facilitate the identification of new proteins playing roles in cellular and molecular interactions underlying female reproductive biology and it is a useful method to identify novel biomarkers of diseases by studying thousands of proteins simultaneously involved in female reproductive tract in healthy state compared to disease state. This review will discuss the best studies areas contributed to female reproductive biology in which gel-based proteomics coupled by MS has been applied to generate proteome of female reproductive tract in a healthy state.

Oral dydrogesterone versus vaginal progesterone gel in the luteal phase support: randomized controlled trial

OBJECTIVES

To compare efficacy, satisfaction and tolerability of oral dydrogesterone and micronized vaginal progesterone gel used for luteal supplementation.

STUDY DESIGN

Randomized controlled trial. A total of 853 infertile women undergoing IVF/ICSI treatment in University Hospital Center "Sisters of Mercy", Zagreb, Croatia. Luteal support was provided as Crinone 8%(®) vaginal progesterone gel (90mg) administered daily, or oral dydrogesterone Duphaston(®) (2× 10mg) administered two times daily. Progesterone was administered from the day of oocyte retrieval (day 0) till pregnancy test or in a case of pregnancy, until week 10.

RESULTS

The on-going pregnancy rates were comparable between Crinone 8%(®) vaginal progesterone gel and oral dydrogesterone - Duphaston(®) (28.1% versus 30.3%; OR 1.11 (0.82-1.49 with 95% CI)). Overall satisfaction and tolerability were significantly higher in the dydrogesterone group than in the Crinone group. Vaginal bleeding, interference with coitus and local adverse side effects such as vaginal irritation and discharge occurred significantly more in Crinone group than in dydrogesterone group.

CONCLUSIONS

Oral dydrogesterone is effective drug, well tolerated and accepted among patients and can be considered for routine luteal support.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01178931; www.clinicaltrials.gov.

Long-term clinical data and molecular defects in the STAR gene in five Greek patients

CONTEXT

Steroidogenic acute regulatory (STAR) gene mutations lead to adrenal and gonadal failure. Interesting, though as yet unexplained, features are the formation of ovarian cysts and the potential presence of CNS findings.

OBJECTIVE

To report biochemical, genetic, and long-term clinical data in five Greek patients from four different families with STAR gene defects (three 46,XX and two 46,XY).

METHODS AND RESULTS

All patients presented in early infancy with adrenal insufficiency. The STAR gene mutation c.834del11bp, detected in three of our patients, completely alters the carboxyl end of the STAR protein and has not thus far been described in other population groups. These three patients belong to three separate families, possibly genetically related, as they live in different villages located in a small region of a Greek island. However, their interrelationship has not been proven. A second mutation, p.W250X, detected in our fourth family, was previously described only in two Serbian patients. Ovarian cysts were detected ultrasonographically in our 46,XX patients and seemed to respond to a low dose of a contraceptive. The histology of an excised ovarian cyst was diagnosed as a corpus luteum (CL) cyst. In two out of the four patients who had undergone brain magnetic resonance imaging, asymptomatic Chiari-1 malformation was observed.

CONCLUSIONS

The occurrence of STAR gene mutation c.834del11bp in three families living in a restricted geographic region could indicate either a founder effect or simply reflect a spread of this defect in a highly related population. The ovarian histological findings suggest that ovarian cysts detected ultrasonographically in 46,XX individuals with STAR gene defects may be CL cysts. The Chiari-1 malformation in two of our patients may be part of the STAR gene mutation phenotype. Nevertheless, more data are needed to confirm or disprove the existence of specific CNS pathology in patients with STAR gene mutations.

The phenotype of hormone-related allergic and autoimmune diseases in the skin: annular lesions that lateralize

Introduction. Sexual dimorphism with an increased prevalence in women has long been observed in various autoimmune, allergic, and skin diseases. Recent research has attempted to correlate this female predilection to physiologic changes seen in the menstrual cycle in order to more effectively diagnose and treat these diseases. Cases. We present five cases of cutaneous diseases in women with annular morphology and distributive features that favor one side over the other. In all cases, skin disease improved with ovarian suppression. Conclusion. Sexual dimorphism in the innate and adaptive immune systems has long been observed, with females demonstrating a more vigorous immune response compared to males. Female sex hormones promote T and B lymphocyte autoreactivity and favor the humoral arm of adaptive immunity. In addition to ovarian steroidogenesis and immunity, intricate pathways coexist in order to engage a single oocyte in each cycle, while simultaneously sustaining the ovarian reserve. Vigorous proinflammatory, vasoactive, and pigment-related cytokines emerge during the demise of the corpus luteum, influencing peripherical sex hormone metabolism of the level of the macrophage and fibroblast. We propose that annular and lateralizing lesions are important manifestations of hormone-related inflammation and recognition of this linkage can lead to improved immune and reproductive health.

The role of progesterone in maternal and fetal medicine

Progesterone is an essential hormone in the process of reproduction. It has been extensively studied in the treatment of different gynecological pathologies, as a contraceptive and in assisted reproductive technologies. However, the use of progesterone in the pathophysiology of pregnancy remains controversial. Progesterone, and its synthetic form 17 α-hydroxyprogesterone caproate (17 OHP-C), offer an effective intervention when the continuation of pregnancy is at risk from immunological factors, luteinic and neuroendocrine deficiencies, and myometrial hypercontractility. Progesterone has been successfully used as prophylaxis in the prevention of spontaneous miscarriage, with treatment beginning from the first trimester of pregnancy. There is substantial evidence, too, to indicate that women with idiopathic recurrent miscarriage may benefit from the immunomodulatory properties of progesterone in early pregnancy. The use of progesterone and 17 OHP-C has been extensively studied in the prevention of preterm birth in a variety of settings. Transvaginal ultrasound measurement of cervical length in singleton pregnancies between 19 and 24 weeks' gestation has been deemed the best way to identify women (approximately 2% of the pregnant population) who would benefit from prophylactic progesterone treatment for the prevention of spontaneous preterm birth. This paper reviews the evidence for the safety and efficacy of the use of progesterone in each of these indications.

Studies on reactivation of regressing bonnet monkey corpus luteum on day 1 of menses: a pilot study

Studies on functional characteristics of the regressing primate corpus luteum (CL) to luteotrophic stimulus on day 1 of the non-fertile menstrual cycle are scarce. Recombinant human luteinizing hormone (rhLH) (20 IU/Kg BW; n = 10) or human chorionic gonadotropin (hCG) (180 IU; n = 6) were administered intravenously to female bonnet monkeys on day 1 of menses. Exogenous treatment of rhLH or hCG caused a significant increase in circulating progesterone (P(4)) levels 2-4 hours post treatment (P < 0.05). Lutectomy prior to onset of menses confirmed that CL is the site of the increased P(4) concentrations. Increased levels of phosphorylated P44/42 MAPK, MKK3/6 activation and concomitant histological changes were observed within 4 hours in CL of monkeys receiving hCG treatment. The results from this study demonstrate the acute progesterone synthesizing capacity of regressing monkey CL after LH or hCG challenge. This has potential implications for interpreting the steroidogenic response after gonadotropin stimulation tests in the early follicular phase of the normal ovulatory and anovulatory women undergoing controlled ovarian stimulation protocols as part of assisted reproductive technology (ART) and in women with polycystic ovarian syndrome.

An integrated view on the luteal phase: diagnosis and treatment in subfertility

The term 'luteal phase deficiency' was first coined more than 60 years ago, and, since then, it has been suggested as a clinical entity per se and an aetiological factor for subfertility, implantation failure and recurrent miscarriage. Despite the existing recommendations for rational work-up in subfertility, luteal phase evaluation and progesterone therapy alone is still common in daily practice. This review comprises results from a Pubmed literature search with the terms 'luteal phase' and 'subfertility', focussing on clinical situations not primarily related to assisted reproduction techniques. Additional data from the experimental studies published in the past 10 years on follicular maturation, oocyte developmental competence and the ovulatory cascade are integrated into the clinical continuum of dysfunctional ovulation, menstrual cycle irregularity and impaired corpus luteum function. As reliable diagnostic tools for adequate luteal function are missing, the presence of clinical symptoms such as cycle irregularity or premenstrual spotting is indicative and should initiate early follicular phase diagnostic work-up. New evidence on the interdependence of oocyte and follicular maturation and resulting developmental competence of the embryo further support the use of ovarian stimulation as the first-line therapeutic option in different subsets of patients with subfertility including luteal phase deficiency.

Prolactin signaling mechanisms in ovary

Prolactin is a hormone that is essential for normal reproduction and signals through two types of receptors. Not only is the classical long form of the prolactin receptor identified, but so are many short form receptors in rodents and human tissues. Mouse mutagenesis studies have offered insight into the biology of prolactin family, providing compelling evidence that the different isoforms have independent biological activity. The possibility that short forms mediate cell proliferation is important for a variety of tissues including mammary gland and ovarian follicles. This review summarizes our current knowledge about prolactin signaling and its role in reproduction through either long or short isoform receptors.

Resveratrol promotes expression of SIRT1 and StAR in rat ovarian granulosa cells: an implicative role of SIRT1 in the ovary

BACKGROUND

Resveratrol is a natural polyphenolic compound known for its beneficial effects on energy homeostasis, and it also has multiple properties, including anti-oxidant, anti-inflammatory, and anti-tumor activities. Recently, silent information regulator genes (Sirtuins) have been identified as targets of resveratrol. Sirtuin 1 (SIRT1), originally found as an NAD+-dependent histone deacetylase, is a principal modulator of pathways downstream of calorie restriction, and the activation of SIRT1 ameliorates glucose homeostasis and insulin sensitivity. To date, the presence and physiological role of SIRT1 in the ovary are not known. Here we found that SIRT1 was localized in granulosa cells of the human ovary.

METHODS

The physiological roles of resveratrol and SIRT1 in the ovary were analyzed. Immunohistochemistry was performed to localize the SIRT1 expression. SIRT1 protein expression of cultured cells and luteinized human granulosa cells was investigated by Western blot. Rat granulosa cells were obtained from diethylstilbestrol treated rats. The cells were treated with increasing doses of resveratrol, and subsequently harvested to determine mRNA levels and protein levels. Cell viability was tested by MTS assay. Cellular apoptosis was analyzed by caspase 3/7 activity test and Hoechst 33342 staining.

RESULTS

SIRT1 protein was expressed in the human ovarian tissues and human luteinized granulosa cells. We demonstrated that resveratrol exhibited a potent concentration-dependent inhibition of rat granulosa cells viability. However, resveratrol-induced inhibition of rat granulosa cells viability is independent of apoptosis signal. Resveratrol increased mRNA levels of SIRT1, LH receptor, StAR, and P450 aromatase, while mRNA levels of FSH receptor remained unchanged. Western blot analysis was consistent with the results of quantitative real-time RT-PCR assay. In addition, progesterone secretion was induced by the treatment of resveratrol.

CONCLUSIONS

These results suggest a novel mechanism that resveratrol could enhance progesterone secretion and expression of luteinization-related genes in the ovary, and thus provide important implications to understand the mechanism of luteal phase deficiency.

Decreased fertility in poor responder women is not related to oocyte morphological status

INTRODUCTION

In women showing impaired fertility, a decreased response to ovarian stimulation is a major problem, limiting the number of oocytes to be used for assisted reproduction techniques (ART). Despite the several definitions of poor response, it is still a matter of debate whether young poor responder patients also show a decrease in oocyte quality. The objective in this study was to investigate whether poor ovarian response to the superstimulation protocol is accompanied by impaired oocyte quality.

MATERIAL AND METHODS

This study included 313 patients younger than 35 years old, undergoing intracytoplasmic sperm injection. Patients with four or fewer MII oocytes (poor-responder group, PR, n = 57) were age-matched with normoresponder patients (NR, n = 256).

RESULTS

A higher rate of oocyte retrieval and a trend towards an increase in MII oocyte rate were observed in the NR group when compared to the PR group (71.6 ±1.1% and 74.1 ±1.0% vs. 56.3 ±2.9% and 66.5 ±3.7%; p< 0.0001 and p = 0.056, respectively). A trend toward increased implantation rates was observed in the NR group when compared to the PR group (44 and 24.5 ±2.0% vs. 28.8 and 16.4 ±3.9%; p= 0.0305 and p= 0.0651, respectively).

CONCLUSIONS

Low response to ovarian stimulation is apparently not related to impaired oocyte quality. However, embryos produced from poor responder oocytes show impaired capacity to implant and to carry a pregnancy to term.

Apoptosis is increased and cell proliferation is decreased in out-of-phase endometria from infertile and recurrent abortion patients

BACKGROUND

Various endometrial abnormalities have been associated with luteal phase deficiency: a significant dyssynchrony in the maturation of the glandular epithelium and the stroma and a prevalence of out-of-phase endometrial biopsy specimens. Out-of phase endometrium is a controversial disorder related to failed implantation, infertility and early pregnancy loss. Given that the regulation of the apoptotic process in endometrium of luteal phase deficiency is still unknown, the aim of this study was to evaluate cell proliferation, apoptosis and the levels of the main effector caspase, caspase-3 in the luteal in-phase and out-of-phase endometrium.

METHODS

Thirty-seven endometrial samples from sterile or recurrent abortion patients were included in this study: 21 in-phase samples (controls) and 16 samples with out-of-phase endometrium. Biopsy specimens of eutopic endometrium were obtained from all subjects during days 21-25 of the menstrual cycle. The endometrium with endometrial maturity of cycle day 25 or less at the time of menstruation was considered out-of phase. Endometrial tissues were fixed in 10% buffered formaldehyde. For apoptosis quantification, sections were processed for in situ immunohistochemical localization of nuclei exhibiting DNA fragmentation, by the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP digoxygenin nick-end labeling (TUNEL) technique. Expressions of Proliferating Cell Nuclear Antigen (PCNA) as a marker of cell proliferation, and of cleaved caspase-3 as a marker of apoptosis, were assessed by immunohistochemistry in the luteal in-phase and out-of-phase endometrium from infertile and recurrent abortion patients.

RESULTS

Luteal out-of-phase endometrium had increased apoptosis levels compared to in-phase endometrium (p < 0.05). Caspase-3 evaluation confirmed these results: the luteal out-of-phase endometrium showed augmented cleaved caspase-3 expression (p < 0.005). As well, our data demonstrated that the luteal out-of-phase endometrium expresses decreased PCNA levels (p < 0.05), showing that cell proliferation is diminished in this tissue.

CONCLUSIONS

this study represents the first report describing variations at the cell proliferation and cell death levels in the out-of-phase endometrium in comparison with in-phase endometrium from infertile and recurrent abortion patients. Further studies are needed to elucidate a potential role of these alterations in the physiopathology of luteal phase deficiency.

Impact of prolactin receptor isoforms on reproduction

Prolactin is a hormone involved in growth, development, reproduction, metabolism, water and electrolyte balance, brain and behavior, and immunoregulation. Its actions on reproductive processes represent the largest group of functions identified for this hormone. Besides the classic long form of the prolactin receptor, many short form receptors have been identified in rodents and human tissues. Mouse mutagenesis studies have offered insight into the biology of the prolactin family, providing compelling evidence that different isoforms have independent biological activity. The possibility that short forms mediate cell proliferation is important for a variety of tissues including mammary glands and ovarian follicles. This review summarizes the current knowledge about prolactin signaling and its role in reproduction through either long or short isoform receptors.