Rise In Estradiol Research Articles

Sex-Specific Effects of Neonatal Stress on Brainstem Expression of Orexin1-Receptors

Introduction and hypothesis: Located within the hypothalamus, orexin-producing neurons (ORX) regulate arousal, feeding, and cardiorespiratory function. Panic disorders (PD) affects ~5% of the North American population. Stress-related “hyperactivation” of the ORX system is a leading hypothesis to explain the pathophysiology of PD. One important sub-group of PD patients show significant respiratory symptoms, including an excessive ventilatory response to CO2 inhalation. Manifestations of PD are sex-specific: the prevalence of PD is ~2 times higher in women compared to men and the intensity of the ventilatory response to CO2 fluctuates with the hormonal cycle. Early life stress is a risk factor for PD and we recently demonstrated that in rats, neonatal maternal separation (NMS) augments the ventilatory response to CO2 (5%; 10 min) of adult females (but not males); this effect peaks with the rise of 17-b estradiol (E2) during proestrus. Because NMS-related enhancement of the hyperventilatory response to CO2 can be prevented by a selective ORX1-antagonist, we tested the hypothesis that sex, hormonal status and NMS interact to influence the expression of ORX-1 receptors in brainstem regions that regulate breathing. Methods: Following birth, pups were either exposed to NMS (3h/day from postnatal days 3 to 12) or raised under standard conditions. Rats were then raised until adulthood (8 weeks); experiments were performed on males, females in proestrus (high E2), and ovariectomised (low E2) females (2 weeks post-surgery). We used in situ hybridization histochemistry to quantify the expression of mRNA for ORX-1 receptors. The ORX-1 receptors signal was revealed by autoradiography emulsion and slides were examined under darkfield microscopy. Expression of ORX-1 receptors was quantified by measuring the pixel density of the hybridization signal in selected brainstem regions that regulate CO2 response. Results: The locus coeruleus (LC) contained the highest expression of ORX-1 receptors amongst the structures studied. In males, NMS was associated with significant decreases in ORX-1 expression in the LC and nucleus of the solitary tract (NTS). By comparison with OVX females, proestrus augmented ORX-1 expression in the LC of controls, but not NMS. By comparison with OVX, proestrus augmented ORX-1 expression in the raphe obscurus, especially in NMS females. Expression of ORX-1 was unchanged in the NTS of females. Conclusion and perspectives: We conclude that sex and the female’s hormonal status are important determinants of ORX-1 expression and that NMS can alter these relationships; however, those effects are structure-specific. In light of the evidence indicating that 5-HT dysfunction contributes to PD, the results observed in the raphe obscurus point to a plausible mechanism. This study was supported by ‘the Québec Heart and Lung Institute Research Foundation’. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Learning exceptions to category rules varies across the menstrual cycle

Ways in which ovarian hormones affect cognition have been long overlooked despite strong evidence of their effects on the brain. To address this gap, we study performance on a rule-plus-exception category learning task, a complex task that requires careful coordination of core cognitive mechanisms, across the menstrual cycle (N = 171). Results show that the menstrual cycle distinctly affects exception learning in a manner that parallels the typical rise and fall of estradiol across the cycle. Participants in their high estradiol phase outperform participants in their low estradiol phase and demonstrate more rapid learning of exceptions than a male comparison group. A likely mechanism underlying this effect is estradiol’s impact on pattern separation and completion pathways in the hippocampus. These results provide novel evidence for the effects of the menstrual cycle on category learning, and underscore the importance of considering female sex-related variables in cognitive neuroscience research.

Differential regulation of Kiss1 gene expression by oestradiol in the hypothalamus of the female Damaraland mole-rat, an induced ovulator

Kisspeptin, a product of the Kiss1 gene is considered a potent stimulator of gonadotropin release, by interacting with its receptor, the G protein-coupled receptor 54. Kiss1 neurons are known to mediate the positive and negative feedback effects of oestradiol on GnRH neurons that control the pulsatile and surge secretion of GnRH. While in spontaneously ovulating mammals the GnRH/LH surge is initiated by a rise in ovarian oestradiol secreted from maturing follicles, in induced ovulators, the primary trigger is the mating stimulus. Damaraland mole rats (Fukomys damarensis) are cooperatively breeding, subterranean rodents that exhibit induced ovulation. We have previously described in this species the distribution and differential expression pattern of Kiss1-expressing neurons in the hypothalamus of males and females. Here we examine whether oestradiol (E2) regulates the hypothalamic Kiss1 expression in a similar way as described for spontaneously ovulating rodent species. By means of in situ hybridisation, we measured Kiss1 mRNA among groups of ovary-intact, ovariectomized (OVX) and OVX females treated with E2 (OVX + E2). In the arcuate nucleus (ARC), Kiss1 expression increased after ovariectomy and decreased with E2 treatment. In the preoptic region, Kiss1 expression after gonadectomy was similar to the level of wild-caught gonad-intact controls, but was dramatically upregulated with E2 treatment. The data suggest that, similar to other species, Kiss1 neurons in the ARC, which are inhibited by E2, play a role in the negative feedback control on GnRH release. The exact role of the Kiss1 neuron population in the preoptic region, which is stimulated by E2, remains to be determined.

Associations between serum copper, zinc, selenium level and sex hormones among 6-19 years old children and adolescents in NHANES 2013-2016.

Copper, zinc, and selenium are essential trace elements for human and have important effects on sex hormones. There are few studies on the relationships between the three trace elements and sex hormones. Therefore, our study aimed to investigate the relationships between serum copper, zinc, selenium and testosterone, estradiol, SHBG using data from the National Health and Nutrition Examination Survey (NHANES) 2013-2016 in participants 6-19 years. 1097 participants were enrolled and stratified into male/female children and adolescents. Weighted linear regression models combined regression diagnosis were used to estimate the relationships between trace elements and sex hormones according to the different stratifications. Our results showed that copper was inversely associated with testosterone and estradiol but positively correlated with SHBG. Zinc had positive relationships with testosterone in male adolescents and female children but an inverse relationship with testosterone in female adolescents. Furthermore, a negative association was observed between zinc and SHBG. With the rise of selenium level, testosterone and estradiol were increased but SHBG was decreased. In general, this study used more standardized statistical methods to investigate the relationships between copper, zinc, selenium and testosterone, estradiol, SHBG. Further study should pay attention to some details in statistical methods.

Intramuscular testosterone cypionate vs subcutaneous testosterone enanthate: Comparing the outcomes in hypogonadal men

ABSTRACT Introduction Intramuscular testosterone cypionate (IM-TC) is the conventional treatment option for hypogonadal men with baseline serum total testosterone (TT) less than 300 ng/dL; however, significant peaks in testosterone cause adverse effects including polycythemia and rise in estradiol (E2). Subcutaneous testosterone enanthate-autoinjectors (SCTE-AI) were designed with a lower testosterone peak-to-trough ratio of 1.8. Objective This dual-institutional study compared the TT, hematocrit (HCT), E2, and prostate-specific antigen (PSA) response to treatment with IM-TC versus SCTE-AI. Methods 263 hypogonadal men were treated with testosterone replacement therapy (TRT) via IM-TC or SCTE-AI. TT, HCT, E2, and PSA levels were obtained at baseline and 6- to 12-weeks post-treatment. Significant differences in baseline and post-treatment levels were identified by univariate analysis. Linear regression models determined whether treatment modality was independently associated with post-TRT levels of TT, HCT, E2, and PSA. Results Patients treated with SCTE-AI were significantly younger, had higher baseline TT levels, and lower baseline E2 levels (Table 1). Post-TRT, the SCTE-AI cohort had significantly lower HCT and E2, while TT and PSA levels were not significantly different between the treatment arms. After adjusting for significant differences with linear regression, SCTE-AI was associated with a 14% greater increase in trough TT levels compared to IM-TC (p=0.027) (Table 2a). Furthermore, SCTE-AI was independently associated with 41% and 26.5% lower post-therapy HCT (p<0.001) and E2 (p<0.001) levels, respectively, when compared to IM-TC (Table 2b-c). Neither TRT modality was associated with post-therapy elevation of PSA (p=0.691). TT: Total Testosterone; HCT: Hematocrit; E2: Estradiol; PSA: prostate-specific antigen Conclusions While IM-TC and SCTE-AI provide a significant increase in testosterone, SCTE-AI is associated with lower levels of post-therapy HCT and E2 compared to IM-TC after adjusting for significant covariates. SCTE-AI is an effective testosterone delivery system with a preferable safety profile over IM-TC. Disclosure Work supported by industry: no. A consultant, employee (part time or full time) or shareholder is among the authors (Antares Pharma, Clarus Therapeutics, Coloplast, Promescent, Viome).

Does adjuvant letrozole reduce uterine peristalsis prior to fresh embryo transfer?

STUDY QUESTIONDoes adjuvant letrozole in ovarian stimulation for IVF decrease the uterine peristalsis frequency (UPF) prior to fresh embryo transfer (ET)?SUMMARY ANSWERAdjuvant letrozole in ovarian stimulation for IVF does not reduce the UPF significantly prior to fresh ET.WHAT IS KNOWN ALREADYThroughout the cycle, uterine peristalsis aids spermatozoa transport to the fallopian tube and may affect implantation. At fresh ET, UPF is negatively correlated with implantation and clinical pregnancy rates and is believed to be modulated by oestradiol and progesterone. High levels of oestradiol, from multiple follicular development, in ovarian stimulation have been reported to increase UPF, whereas progesterone is considered to be an utero-relaxant. The influence of androgens is unclear. Co-treatment with letrozole during gonadotropin ovarian stimulation limits the supra-physiological oestradiol rise and may therefore reduce UPF prior to fresh ET.STUDY DESIGN, SIZE, DURATIONThis study was carried out on subjects participating in a single-centre double-blinded randomized controlled trial of the impact of letrozole on follicle development and endocrine profiles, and investigated the impact of adjuvant letrozole in ovarian stimulation for IVF on UPF prior to fresh ET and the correlations of UPF with endocrine markers. Between 2016 and 2017, 39 women expected to be normal responders were randomized to co-treatment with letrozole or placebo. Of these, 33 women completed this element of the study. The study was carried out according to the Helsinki Declaration and the ICH-Good-Clinical-Practice.PARTICIPANTS/MATERIALS, SETTING, METHODSEligible women were randomized 1:1 to adjuvant treatment with letrozole 5 mg/day or placebo in an antagonist protocol using a fixed dose of recombinant (r) FSH 150 IU/day. Final maturation was triggered with hCG 6500 IU and luteal support with vaginal progesterone was administered from the day following oocyte aspiration. Less than 1 h prior to fresh ET, 6-min duration transvaginal ultrasound recordings of the uterus in sagittal section were performed and blood samples were drawn.MAIN RESULTS AND THE ROLE OF CHANCEA total of 33 women completed the study (letrozole n = 17; placebo n = 16). Age, BMI and ovarian reserve markers were similar between the groups. On the day of ET, serum oestradiol levels were significantly suppressed in the letrozole group to a mean of 867 ± 827 pmol/l compared to 3110 ± 1528 pmol/l in the placebo group (P < 0.001). Mean UPF prior to fresh ET did not differ between the intervention and placebo group (3.3 ± 0.36 versus 3.5 ± 0.51 per minute respectively, P = 0.108). UPF was assessed and agreed by two observers who were blinded to adjuvant treatment. Two patients were excluded due to poor quality of the ultrasound recordings. Supra-physiological serum oestradiol in the placebo group were negatively correlated with UPF (P = 0.014; R = –0.62), but the more physiological serum oestradiol levels in the letrozole group showed no correlation with UPF (P = 0.567; R = 0.15). Serum progesterone levels were similar in both groups and did not show any significant correlation with UPF. Testosterone levels were significantly higher in the letrozole group (P = 0.005) and showed a non-significant trend that negatively correlated with UPF in the placebo group (P-value = 0.071, R = –0.48).LIMITATIONS, REASONS FOR CAUTIONLimitations of the study included the limited sample size and the lack of a power calculation specifically determined for this endpoint.WIDER IMPLICATIONS OF THE FINDINGSThe supra-physiological levels of oestradiol generated during ovarian stimulation were significantly suppressed in the intervention group. However, UPF prior to fresh ET was similar in both groups. Modulating the luteal phase sex steroids with adjuvant letrozole had little measured impact on UPF. Any beneficial effect of adjuvant letrozole during ovarian stimulation is unlikely to be due to significant modulation of UPF.STUDY FUNDING/COMPETING INTEREST(S)M.D.H.’s salary was funded by an unrestricted research grant from Gedeon Richter. The expenses of the study were funded by a scientific collaboration: ReproUnion, co-financed by the European Union, Interreg Öresund-Kattegat-Skagerrak and Ferring Pharmaceuticals. The assays for the analyses were funded by Roche Diagnostics and an unrestricted research grant from Merck Life Science AS, Denmark. The authors have no competing interests to declare regarding this study.TRIAL REGISTRATION NUMBERClinicaltrials.gov: NCT02939898, EudraCT no.: 2015-005683-41.

Adolescent Development of Biological Rhythms in Female Rats: Estradiol Dependence and Effects of Combined Contraceptives.

Adolescence is a period of continuous development, including the maturation of endogenous rhythms across systems and timescales. Although, these dynamic changes are well-recognized, their continuous structure and hormonal dependence have not been systematically characterized. Given the well-established link between core body temperature (CBT) and reproductive hormones in adults, we hypothesized that high-resolution CBT can be applied to passively monitor pubertal development and disruption with high fidelity. To examine this possibility, we used signal processing to investigate the trajectory of CBT rhythms at the within-day (ultradian), daily (circadian), and ovulatory timescales, their dependence on estradiol (E2), and the effects of hormonal contraceptives. Puberty onset was marked by a rise in fecal estradiol (fE2), followed by an elevation in CBT and circadian power. This time period marked the commencement of 4-day rhythmicity in fE2, CBT, and ultradian power marking the onset of the estrous cycle. The rise in circadian amplitude was accelerated by E2 treatment, indicating a role for this hormone in rhythmic development. Contraceptive administration in later adolescence reduced CBT and circadian power and resulted in disruption to 4-day cycles that persisted after discontinuation. Our data reveal with precise temporal resolution how biological rhythms change across adolescence and demonstrate a role for E2 in the emergence and preservation of multiscale rhythmicity. These findings also demonstrate how hormones delivered exogenously in a non-rhythmic pattern can disrupt rhythmic development. These data lay the groundwork for a future in which temperature metrics provide an inexpensive, convenient method for monitoring pubertal maturation and support the development of hormone therapies that better mimic and support human chronobiology.

P–465 Effect of letrozole over Ki–67 expression in breast cancer during controlled ovarian stimulation (COS) for fertility preservation (FP): case report

Abstract Study question Does concomitant letrozole administration during COS alter Ki–67 expression in women undergoing FP procedures before breast cancer surgery? Summary answer Concomitant letrozole administration during COS, even for a short period, can reduce Ki–67 expression in breast cancer. What is known already The biggest concern with COS in breast cancer patients is the increase in serum estradiol levels, caused by the development of multiple follicles simultaneously. This has always been a major hindrance to the use of traditional ovarian stimulation regimens in these patients, due to the large amount of evidence on the pathogenetic role of estrogen in breast cancer propagation. To limit the rise of estradiol during COS, most centers have adopted concomitant letrozole administration. Recently, some studies have reported changes in tumor pathology after letrozole administration, such as a significant fall in Ki–67 expression. Study design, size, duration Case report including 2 patients undergoing COS with concomitant letrozole administration for 12 days before breast cancer surgery. Participants/materials, setting, methods The first patient was a 28-year-old Caucasian woman with a breast biopsy showing an infiltrating ductal carcinoma in the upper external quadrant of the right breast. The second patient was a 33-year-old Caucasian woman with a diagnosis of infiltrating ductal carcinoma of the upper external quadrant of the left breast. Both patients underwent COS with concomitant letrozole administration 5 mg daily for 12 days. Ovarian stimulation was performed using a GnRH-antagonist random-start protocol. Main results and the role of chance In the first patient, Ki–67 expression in the initial biopsy was 55%. After completion of FP procedures, she underwent quadrantectomy with sentinel-lymphnode biopsy. In the final histopathological report Ki–67 expression fell to 25%. In the second patient, the first biopsy showed a Ki–67 expression of 30%, while after mastectomy it fell to 10%. Limitations, reasons for caution Only 2 patients were included in the study. Wider implications of the findings: COS is feasible before breast cancer surgery, as long as an adequate cancer biopsy with immunohistochemical evaluation has been collected. Cytological diagnosis is not enough to start FP procedures. Evaluation of biological parameters after letrozole administration could lead to underestimation of cancer proliferation rate and to inappropriate treatment strategies. Trial registration number NA

P–613 Adjuvant letrozole in ovarian stimulation for in vitro fertilization does not reduce uterine peristalsis frequency prior to fresh embryo transfer

Abstract Study question Does adjuvant letrozole in ovarian stimulation (OS) for in vitro fertilization (IVF) decrease the uterine peristalsis frequency (UPF) prior to fresh embryo transfer (ET)? Summary answer Adjuvant letrozole in (OS) for IVF does not reduce the UPF significantly prior to fresh ET. What is known already Throughout the cycle UPF aids spermatozoa transport to the fallopian tube and may affect implantation. At fresh, ET UPF is negatively correlated with implantation- and clinical pregnancy rates and is believed to be modulated by estradiol and progesterone. High levels of estradiol, from multiple follicular development, in OS have been reported to increase UPF, whereas progesterone is considered to be utero-relaxant. The influence of androgens is unclear. Co-treatment with letrozole during gonadotropin OS limits the estradiol rise the supra-physiological estradiol and may therefore reduce UPF prior to fresh ET. Study design, size, duration: This single centre study was nested within a multicentre double blinded RCT investigating the impact of letrozole co-treatment during gonadotropin OS for IVF on late follicular and luteal estradiol, progesterone and testosterone levels. Between 2016 and 2017, 39 women expected normal responders were randomised to co-treatment with letrozole or placebo. Of these, 33 women completed this element of the study. The study was carried out according to the Helsinki Declaration and the ICH-Good-Clinical-Practice. Participants/materials, setting, methods Eligible women were randomised 1:1 to adjuvant treatment with letrozole 5 mg/day or placebo in an antagonist protocol using a fixed dose of recFSH 150 IU/day. Final maturation was triggered with rhCG 6,500 IU and luteal support with vaginal progesterone was administered from the day following oocyte aspiration. Less than one hour prior to fresh ET, six minute duration transvaginal ultrasound recordings of the uterus in sagittal section were performed and blood samples were drawn. Main results and the role of chance A total of 33 women completed the study (letrozole n = 17; placebo n = 16). Age, BMI, and ovarian reserve markers were similar between the groups. On day of ET, serum estradiol levels were significantly suppressed in the letrozole group to mean 867 ± 827 pmol/L compared to 3,110 ± 1,528 pmol/L in the placebo group (P &amp;lt; 0.0001). Mean UPF prior to fresh ET did not differ between the intervention and control group (3.3 ± 0.36 versus 3.5 ± 0.51 per minute respectively, P = 0.108). UPF was assessed and agreed by two observers who were blind to adjuvant treatment. Two patients were excluded due to poor quality of the ultra sound recording. Supra-physiological serum estradiol in the placebo group was negatively correlated with UPF (P = 0.014; R = –0.62), but the more physiological serum estradiol levels in the letrozole group showed no correlation with UPF (P = 0.567; R = 0.15). Serum progesterone levels were similar in both groups and did not show any significant correlation with UPF. Testosterone levels were significantly higher in the letrozole group (P = 0.005) and showed a non-significant trend negatively correlated with UPF in the placebo group (P-value=0.07, R= –0.48). Limitations, reasons for caution The limited sample size risks masking minor effects. Wider implications of the findings: The supra-physiological levels of estradiol were significantly supressed in the intervention group, but UPF prior to fresh ET was similar in both groups. UPF is not strongly correlated to luteal phase sex steroid levels. Any beneficial effect of adjuvant letrozole during OS is not through an impact of UPF. Trial registration number NCT02939898

The Straw That Broke the Camel's Back: Natural Variations in 17β-Estradiol and COMT-Val158Met Genotype Interact in the Modulation of Model-Free and Model-Based Control.

The sex hormone estradiol has recently gained attention in human decision-making research. Animal studies have already shown that estradiol promotes dopaminergic transmission and thus supports reward-seeking behavior and aspects of addiction. In humans, natural variations of estradiol across the menstrual cycle modulate the ability to learn from direct performance feedback (“model-free” learning). However, it remains unclear whether estradiol also influences more complex “model-based” contributions to reinforcement learning. Here, 41 women were tested twice – in the low and high estradiol state of the follicular phase of their menstrual cycle – with a Two-Step decision task designed to separate model-free from model-based learning. The results showed that in the high estradiol state women relied more heavily on model-free learning, and accomplished reduced performance gains, particularly during the more volatile periods of the task that demanded increased learning effort. In contrast, model-based control remained unaltered by the influence of hormonal state across the group. Yet, when accounting for individual differences in the genetic proxy of the COMT-Val158Met polymorphism (rs4680), we observed that only the participants homozygote for the methionine allele (n = 12; with putatively higher prefrontal dopamine) experienced a decline in model-based control when facing volatile reward probabilities. This group also showed the increase in suboptimal model-free control, while the carriers of the valine allele remained unaffected by the rise in endogenous estradiol. Taken together, these preliminary findings suggest that endogenous estradiol may affect the balance between model-based and model-free control, and particularly so in women with a high prefrontal baseline dopamine capacity and in situations of increased environmental volatility.

Avoidance Learning Across the Menstrual Cycle: A Conceptual Replication.

Hormonal transitions across the menstrual cycle may modulate human reward processing and reinforcement learning, but previous results were contradictory. Studies assessed relatively small samples (n < 30) and exclusively used within-subject designs to compare women in hormonally distinct menstrual cycle phases. This increased the risk of sporadic findings and results may have been disproportionally affected by expectancy effects. Also, replication studies are widely missing, which currently precludes any reliable inferences. The present study was intended as a conceptual replication of a previous study [(1), Neuropsychologia 84; n = 15]. There, we had observed a reduction in avoidance learning capacity when women were in the high estradiol state of the late follicular phase as compared to the mid luteal phase with enhanced progesterone influence. These results conformed to the idea that estradiol and progesterone may antagonistically modulate dopaminergic transmission as a dopamine agonist and antagonist, respectively. Heightened progesterone in the luteal phase thereby supported the ability to learn from the negative outcomes of one's actions, while the follicular rise in estradiol interfered with this capacity. Here, we re-examined the above described within-subject difference between the follicular and the luteal phase in a between-subjects design. Seventy-five women were tested once with a probabilistic feedback learning task, while being either in the follicular (36 women) or luteal phase (39 women), and were compared for phase-related differences in behavior. Secondly, we combined the new data with data from three previous studies from our laboratory that used the same task and menstrual cycle phases. This meta-analysis included only data from the first test day, free of any biasing expectancy effects. Both analyses demonstrated the consistency of the decline in avoidance learning in the follicular relative to the luteal phase. We also showed that this decline reliably occurred in all of the included samples. Altogether, these results provide evidence for the consistency of a behavioral difference and its apparent association with a transient change in hormonal state that occurs in the natural menstrual cycle. Our findings may also open new avenues for the development of reliable between-subjects test protocols in menstrual cycle research.

The effect of estroprogestagen therapy on lipid status in menopause depending on the drug administration route

Background/Aim. In menopausal women lipid and lipoprotein values are important predictors of development of cardiovascular diseases (CVD). The use of estrogens reduces levels of low density lipoprotein cholesterol (LDLC) and lipoprotein A [Lp(a)], and increases levels of triglycerides (TG) and high density lipoprotein cholesterol (HDL-C) depending on the dose and route of administration. Simultaneous administration of progesterone, depending on the type, can have different effects on lipids. The aim of the study was to examine the effect of estroprogestagen therapy on the lipid metabolism of women in menopause, depending on the administration route. Methods. A study was conducted as prospective clinical interventional study with controlled parallel groups. It included 64 women in menopause, divided into three groups: the group 1 (n = 22) on oral therapy with estroprogestagens, the group 2 (n = 17) on transdermal patch therapy with estroprogestagens and the group 3 (n = 25) treated with estroprogestagens given intramuscularly. The following biochemical parameters in the serum were determined: total cholesterol (TC), HDL-C, LDL-C, TG, Lp(a), apoprotein A (Apo-A), apoprotein B (Apo-B), follicle- stimulating hormone (FSH), luteinizing hormone (LH), estradiol, progesterone, testosterone, sex hormonebinding globulin (SHBG), dehydroepiandrosterone sulfate (DHEA-SO4), prolactin and thyroid-stimulating hormone (TSH), prior to administration of the menopausal hormonal therapy (MHT), as well as after sixth months and 2?5 years from the beginning of the therapy. The statistical significance of the difference in values obtained was examined independently and depending on the route of MHT application. Results. MHT, regardless of the administration route, led to a statistically significant continuous decrease of TC, LDL-C and Apo-B levels and the continuous increase of HDL-C and Apo-A levels. Serum levels of TC, LDL-C, HDL-C, Lp(a), Apo-A and Apo-B did not show a statistically significant differences among groups of women given MHT by different routes. It was found that the serum level of Apo-A increased significantly with the rise of estradiol, and the values of LDL and Apo-B decreased regardless of the route of the MHT application. Conclusion. MHT introduced in time, regardless of the route of administration, has beneficial effects on the lipid status of menopausal women and consequently might prevent numerous cardiovascular diseases that are the leading cause of mortality.

A Higher Estradiol Rise After Dual Trigger in Progestin-Primed Ovarian Stimulation Is Associated With a Lower Oocyte and Mature Oocyte Yield in Normal Responders.

Background: Prior studies have shown that patients with a >10% estradiol (E2) rise after trigger had more oocytes retrieved than plateauing or decreasing E2 responders. However, multiple follicles develop at different stages of maturation during controlled ovarian stimulation (COS) and may exhibit different responses to trigger. The association between the magnitude of E2 increase and oocyte retrieval outcomes is still unclear.Methods: This was a retrospective cohort study of 2,898 women undergoing their first COS cycles with normal response from January 2014 to December 2017 at a tertiary-care academic medical center. Patients were categorized into five groups according to the percentage increase in E2 levels before and after dual trigger: <10.0%, 10.0–19.9%, 20.0–29.9%, 30.0–39.9%, and ≥40.0%. Univariable and multivariable linear regression analysis were performed to explore the association between E2 increase and oocyte/mature oocyte yield, while logistic regression was used to assess its effect on low oocyte/mature oocyte yield (<10th percentile).Results: The post-trigger E2 increase was negatively associated with both oocyte yield (P-trend < 0.001, adjusted P-trend = 0.033) and mature oocyte yield (P-trend < 0.001, adjusted P-trend = 0.002). Compared with a <10.0% E2 increase after trigger, patients with a ≥40.0% rise had fewer mature oocyte yield [adjusted mean absolute difference [MD] = −5.2, 95% confidence interval [CI]: −8.2–−1.8] and higher risk of low mature oocyte yield (adjusted odds ratio [OR] = 1.64, 95% CI: 1.04–2.60), whereas no statistical significance was found in oocyte yield (adjusted MD = −2.7, 95% CI: −6.1–0.8) and low oocyte yield (adjusted OR = 1.48, 95% CI: 0.96–2.28). In addition, the rates of implantation, positive pregnancy test, clinical pregnancy, ongoing pregnancy, pregnancy loss, and live birth were comparable among the 1,942 frozen embryo transfer cycles with embryos originating from different groups of E2 increase (all P > 0.05).Conclusions: A higher E2 rise after dual trigger is independently associated with a lower oocyte and mature oocyte yield in normal responders. Further studies are needed to explore the efficacy of individualized time interval from trigger to oocyte retrieval based on the magnitude of E2 increase after trigger.

SAT-211 Gonadotrophin Rise Following Kisspeptin Analogue (MVT-602) Is Increased In Women With Hypothalamic Amenorrhoea Compared To Healthy Women

Background Hypothalamic amenorrhoea (HA) is a condition characterised by reduced GnRH pulsatility as a result of low body weight, excessive exercise, or psychological stress. HA leads to anovulatory infertility and osteoporosis. Kisspeptin is a neuropeptide that is known to be a key regulator of hypothalamic GnRH function. Hypothalamic kisspeptin expression is reduced, and kisspeptin receptor expression increased, in a rodent model of HA. We have previously demonstrated that a continuous infusion of the native form of kisspeptin (kisspeptin-54; KP54) can restore GnRH pulsatility in women with HA, but excessive doses cause tachyphylaxis. Kisspeptin analogue (MVT-602) is a modified form of kisspeptin with a longer half-life compared to native kisspeptin-54 (1.5-2.2h vs 0.5h). Importantly, the more prolonged gonadotrophin profile induced by MVT-602 could enable restoration of physiological hormonal secretion with less frequent administration than by KP54, and thus mitigate against the risk of tachyphylaxis. We therefore investigated the hormonal response to MVT-602 in women with HA to evaluate its potential future utility in the treatment of anovulatory infertility. Methods A previous dose-finding study during the follicular phase of healthy women determined that no further increase in gonadotrophin rise was observed at doses of MVT-602 higher than 0.03nmol/kg. We therefore compared the gonadotrophin rise following a subcutaneous bolus of MVT-602 at a dose of 0.03nmol/kg in 6 women with HA compared to 9 healthy women studied during the follicular phase of their menstrual cycle (day 1-4). Serum gonadotrophin and oestradiol levels were monitored every 30mins for 24hrs. Groups were compared by unpaired t test. Results The maximal rise in LH following MVT-602, was over two-fold greater in women with HA compared to healthy women in the follicular phase (mean±SD of maximal change in LH: HA 18.3±11.0iU/L, follicular phase 7.4±2.7iU/L; P=0.01). The time to peak LH was expedited in women with HA (time to first peak: HA 380±53mins, follicular phase 1067±415mins; P=0.002). Serum FSH rise was also augmented by over four-fold in women with HA (mean±SD of maximal change in FSH: HA 10.0±4.4iU/L, follicular phase 2.2±1.6iU/L; P=0.0003). Maximal rise in oestradiol was higher in women with HA (700pmol/L) when compared with healthy women (297pmol/L; P=0.03). Conclusion In women with HA, the rise in gonadotrophins following MVT-602 is more pronounced and occurs sooner than in healthy women during the follicular phase. The augmented and sustained rise in oestradiol highlights the potential for MVT-602 to be used as an ovulation induction agent in women with anovulatory HA. Therefore, further research is indicated to evaluate repeated administration of MVT-602 as a novel therapeutic approach to restore fertility in HA.

Med12 regulates ovarian steroidogenesis, uterine development and maternal effects in the mammalian egg.

The transcriptional factor MED12 is part of the essential mediator transcriptional complex that acts as a transcriptional coactivator in all eukaryotes. Missense gain-of-function mutations in human MED12 are associated with uterine leiomyomas, yet the role of MED12 deficiency in tumorigenesis and reproductive biology has not been fully explored. We generated a Med12 reproductive conditional knockout mouse model to evaluate its role in uterine mesenchyme, granulosa cells, and oocytes. Mice heterozygous for Med12 deficiency in granulosa cells and uterus (Med12fl/+ Amhr2-Cre) were subfertile, while mice homozygous for Med12 deficiency in granulosa cells and uterus (Med12fl/fl Amhr2-Cre) were infertile. Morphological and histological analysis of the Med12fl/fl Amhr2-Cre reproductive tract revealed atrophic uteri and hyperchromatic granulosa cells with disrupted expression of Lhcgr, Esr1, and Esr2. Med12fl/fl Amhr2-Cre mice estrous cycle was disrupted, and serum analysis showed blunted rise in estradiol in response to pregnant mare serum gonadotropin. Uterine atrophy was partially rescued by exogenous steroid supplementation with dysregulation of Notch1 and Smo expression in steroid supplemented Med12fl/fl Amhr2-Cre uteri, indicating intrinsic uterine defects. Oocyte-specific ablation of Med12 caused infertility without disrupting normal folliculogenesis and ovulation, consistent with maternal effects of Med12 in early embryo development. These results show the critical importance of Med12 in reproductive tract development and that Med12 loss of function does not cause tumorigenesis in reproductive tissues.

Subcutaneous infusion of kisspeptin-54 stimulates gonadotrophin release in women and the response correlates with basal oestradiol levels

BACKGROUND AND OBJECTIVE Kisspeptin stimulates hypothalamic GnRH secretion resulting in gonadotrophin release and has potential as a future therapeutic. Chronic subcutaneous infusion of kisspeptin via a pump (similar to an insulin pump) may provide an alternative route of administration in the future. We investigated for the first time in humans, the gonadotrophin response to subcutaneous (SC) infusions of kisspeptin-54 in healthy women. Women are markedly more responsive to exogenous kisspeptin in the late follicular phase preovulation when oestradiol levels are naturally high. Therefore, we further investigated whether there was a correlation between baseline oestradiol levels and LH response to kisspeptin. DESIGN AND PATIENTS A prospective, single-blinded placebo-controlled study. Healthy women (n = 4) received an 8-h SC infusion of kisspeptin-54 0·1, 0·3 or 1·0 nmol/kg/h or saline in the early follicular phase of 4 separate menstrual cycles. Gonadotrophins and oestradiol were measured every 10 min during the infusions. RESULTS SC infusion of kisspeptin-54 increased LH and FSH. The LH response to SC infusion of kisspeptin-54 (0·3 and 1·0 nmol/kg/h) positively correlated with baseline oestradiol levels (P < 0·001). Further statistical analyses showed that in the 1·0 nmol/kg/h group, a 100pmol/l rise in baseline oestradiol was associated with a 1·0 IU/l increase in LH. CONCLUSIONS Kisspeptin administered via a SC infusion could be a viable future therapeutic route of administration for patients with infertility. Baseline oestradiol levels may be an important determinant of the gonadotrophin response to kisspeptin treatment in women and should be taken into consideration when evaluating gonadotrophin response.

GnRH antagonist administered twice the day before hCG trigger combined with a step-down protocol may prevent OHSS in IVF/ICSI antagonist cycles at risk for OHSS without affecting the reproductive outcomes: a prospective randomized control trial.

The purpose this study is to investigate whether a double antagonist dose (0.25mg/12h) administered the day before hCG trigger is effective in preventing ovarian hyperstimulation syndrome (OHSS) in GnRH antagonist IVF/intracytoplasmic sperm injection (ICSI) cycles at risk for OHSS. This is a prospective randomized control study, conducted from November 2012 to January 2016. A total of 194 patients undergoing a IVF/ICSI GnRH antagonist cycle that were at risk of OHSS and chose to proceed with embryo transfer and avoid cycle cancellation or embryo cryopreservation were allocated into two groups. The inclusion criteria consisted of a rapid rise of oestradiol ≥3500pg/ml combined with ≥18 follicles >11mm in diameter without any mature follicle >16mm, in any day of stimulation. Overall, 97 patients (intervention group A) received a double dose of GnRH antagonist (0.25mg/12h) the day before hCG while 97 patients (control group B) did not. Recombinant FSH administration was tapered to 100IU/24h the day of the allocation in both groups. Incidence of early-onset moderate/severe OHSS was significantly lower in intervention group A compared to control group B (0 vs 12.37%, P<0.001). Clinical pregnancy rate per cycle (50.52 vs 42.27%, P=0.249) was not significantly different between the two groups. Oestradiol (3263.471±1271.53 vs 5233±1425.17, P<0.001), progesterone (0.93±0.12 vs 1.29±0.14, P<0.001) and luteinizing hormone (1.42±0.31 vs 1.91±0.33, P<0.001) were significantly lower in group A the day of the hCG triggering. The administration of a rescue double GnRH antagonist dose the day before hCG trigger may represent a safe alternative preventive strategy for early OHSS without affecting the reproductive outcomes. ISRCTN02750360.

Exposure to Acute Psychosocial Stress Disrupts the Luteinizing Hormone Surge Independent of Estrous Cycle Alterations in Female Mice.

The disruptive effects of severe stress on reproductive function are well documented, but surprisingly few studies exist that demonstrate milder psychosocial stressors interfere with the ovarian cycle in females. We hypothesized repeated application of psychosocial stress would disrupt estrous cycles in mice. Mice were transferred to a new cage, transported to a new room, and restrained (2 hours) for 21 consecutive days. Contrary to our hypothesis, this paradigm did not affect estrous cycles. We next tested the hypothesis that a single exposure to mild stress disrupts a specific aspect of the cycle: the proestrous luteinizing hormone (LH) surge. We developed a model of acute, layered psychosocial stress (sequential application of new cage, transport to new room, restraint and predator cues lasting 5 hours total) that consistently increased circulating corticosterone. Application of this stress paradigm on midmorning of proestrus disrupted the LH surge measured near lights out in 14 of 24 mice; there was no evidence for a 24-hour delay of the surge. Following stress, mice continued to have normal estrous cycles, even when the LH surge was disrupted. Stressed mice failing to exhibit an LH surge had uterine masses suggesting the proestrous estradiol rise occurred. To test specifically whether the layered stress paradigm blocks estradiol-dependent positive feedback mechanisms, we examined the estradiol-induced LH surge. Stress blocked the estradiol-induced LH surge in all mice. These results suggest exposure to mild, acute psychosocial stress on proestrus can severely disrupt the generation of the LH surge in mice without affecting the overall estrous cycle.

Gonadotropin-releasing hormone receptor (Gnrhr) gene knock out: Normal growth and development of sensory, motor and spatial orientation behavior but altered metabolism in neonatal and prepubertal mice.

Gonadotropin-releasing hormone (GnRH) is important in the control of reproduction, but its actions in non-reproductive processes are less well known. In this study we examined the effect of disrupting the GnRH receptor in mice to determine if growth, metabolism or behaviors that are not associated with reproduction were affected. To minimize the effects of other hormones such as FSH, LH and sex steroids, the neonatal-prepubertal period of 2 to 28 days of age was selected. The study shows that regardless of sex or phenotype in the Gnrhr gene knockout line, there was no significant difference in the daily development of motor control, sensory detection or spatial orientation among the wildtype, heterozygous or null mice. This included a series of behavioral tests for touch, vision, hearing, spatial orientation, locomotory behavior and muscle strength. Neither the daily body weight nor the final weight on day 28 of the kidney, liver and thymus relative to body weight varied significantly in any group. However by day 28, metabolic changes in the GnRH null females compared with wildtype females showed a significant reduction in inguinal fat pad weight normalized to body weight; this was accompanied by an increase in glucose compared with wildtype females shown by Student-Newman-Keuls Multiple Comparison test and Student's unpaired t tests. Our studies show that the GnRH-GnRHR system is not essential for growth or motor/sensory/orientation behavior during the first month of life prior to puberty onset. The lack of the GnRH-GnRHR axis, however, did affect females resulting in reduced subcutaneous inguinal fat pad weight and increased glucose with possible insulin resistance; the loss of the normal rise of estradiol at postnatal days 15–28 may account for the altered metabolism in the prepubertal female pups.

Striatal GDNF Production Is Independent to Circulating Estradiol Level Despite Pan-Neuronal Activation in the Female Mouse.

Gender difference in Parkinson’s disease (PD) suggests that female sex steroids may promote dopaminergic neuron survival and protect them from degeneration. The glial cell line-derived neurotrophic factor (GDNF) is believed to be dopaminotrophic; thus it is considered as a potential therapeutic target in PD. Additionally, GDNF is endogenously synthetized in the caudate/putamen of humans and striatum in rodents. A neuroprotective role of estrogens on the nigrostriatal pathway via the stimulation of GDNF has been proposed. Since the GDNF-producing parvalbumin (Parv) interneurons express the estrogen receptor alpha in the mouse striatum, we sought to determine whether ectopic estrogenic compound modulates the GDNF synthesis in mice. Using an ovariectomized-estradiol (E2) replacement regimen, which reliably generates a rise of plasma estradiol, we assessed the effects of different levels of E2 on the activation of striatal neuronal populations, and GDNF production. A strong correlation was found between plasma E2 and the expression of the immediate early gene cFos in the striatum, as well as in other cortical regions. However, moderate and high E2 treatments failed to induce any striatal GDNF mRNA and protein synthesis. High E2 only stimulates cFos induction in a low percentage of striatal Parv neurons whereas the majority of cFos-positive cells are medium spiny neurons. Activation of these projecting neurons by E2 suggests a role of circulating sex steroids in the modulation of striatal neural pathways.