Association of serum inhibin a with pre-eclampsia: An observational cohort study with propensity score matching

OBJECTIVE

To assess whether serum inhibin A at 14-20 weeks of gestation is associated with the occurrence of pre-eclampsia.

METHODS

A retrospective cohort study using propensity score matching was conducted on 11 682 singleton pregnant women with established deliveries at the Obstetrics and Gynecology Hospital of Fudan University between January 2017 and July 2019. We investigated serum inhibin A levels at 14-20 weeks of gestation and calculated the relative risk between inhibin A and pre-eclampsia by multifactorial logistic regression analysis. Smoothed, fitted curves were used to observe the effect of inhibin A in relation to the occurrence of pre-eclampsia.

RESULTS

The risk of pre-eclampsia occurrence increased with elevated serum inhibin A. After full adjustment for confounders, the risk ratio for pre-eclampsia in the group of pregnant women with high inhibin A was 2.92 (95% confidence interval [CI] 2.08-4.11) compared with those with normal inhibin A. The results of sensitivity analysis suggested a consistent effect of inhibin A on the risk of pre-eclampsia in different populations.

CONCLUSION

Elevated serum inhibin A at 14-20 weeks of gestation is associated with pre-eclampsia and may provide an early warning signal for pregnancy outcomes associated with pre-eclampsia.

Inhibin-Positive "Cholangioblastic" Variant of Intrahepatic Cholangiocarcinoma: Report of 3 New Patients With Review of the Literature

Cholangiocarcinoma is the second most common primary liver malignant neoplasm. It usually affects older individuals in their seventh decade of life with no gender predilection. Recently, a distinct subtype of cholangiocarcinoma has emerged with 2 proposed names: "cholangioblastic" and "solid tubulocystic." This variant predominantly occurs in younger women who lack the common risk factors for patients diagnosed with cholangiocarcinomas, such as older age and chronic liver disease or cirrhosis. We describe 3 new patients with a cholangioblastic variant of intrahepatic cholangiocarcinoma. At the time of diagnosis, the patients were aged 19-, 46-, and 28-year-old; 2 females and 1 male (the 46-year-old). None of our patients had a history of chronic liver disease or known predisposing factors for liver tumors. Tumor size ranged from 2.3 to 23 cm in greatest dimension. Histological examination of these tumors demonstrated reproducible morphology characterized by trabecular, nested, and multicystic patterns with micro and macro follicles filled with eosinophilic material. The immunohistochemical profile showed that the tumor cells were positive for keratin 7, inhibin, synaptophysin, and albumin in situ hybridization, while negative for HepPar1, arginase, and INSM1. All tumors lacked conventional intrahepatic cholangiocarcinoma/adenocarcinoma morphology. We also review the literature and emphasize that neuroendocrine tumors should be recognized as a major diagnostic pitfall of this variant.

Biochemical Screening for Fetal Trisomy 21: Pathophysiology of Maternal Serum Markers and Involvement of the Placenta

It is now well established that maternal serum markers are often abnormal in fetal trisomy 21. Their determination is recommended for prenatal screening and pregnancy follow-up. However, mechanisms leading to abnormal maternal serum levels of such markers are still debated. Our objective was to help clinicians and scientists unravel the pathophysiology of these markers via a review of the main studies published in this field, both in vivo and in vitro, focusing on the six most widely used markers (hCG, its free subunit hCGβ, PAPP-A, AFP, uE3, and inhibin A) as well as cell-free feto-placental DNA. Analysis of the literature shows that mechanisms underlying each marker's regulation are multiple and not necessarily directly linked with the supernumerary chromosome 21. The crucial involvement of the placenta is also highlighted, which could be defective in one or several of its functions (turnover and apoptosis, endocrine production, and feto-maternal exchanges and transfer). These defects were neither constant nor specific for trisomy 21, and might be more or less pronounced, reflecting a high variability in placental immaturity and alteration. This explains why maternal serum markers can lack both specificity and sensitivity, and are thus restricted to screening.

The Importance of Evaluating Serum Levels of Tumor Markers M2-PK and Inhibin A in Patients Undergoing Colonoscopy

Despite the use of colonoscopy to detect colon cancer due to its aggressiveness, high cost, and lack of patient compliance, the use of laboratory tests with high accuracy and sensitivity, such as tumor marker M2-PK and Inhibin A is recommended and can be effective for early diagnosis and screening of patients in the early stages. We studied 46 patients admitted it the gastrointestinal ward of Amir al Momenin Hospital and 45 normal (age and sex-matched) subjects as a control group (case-control and retrospective studies). Before the colonoscopy, the level of tumor marker M2-PK in the stool sample and the serum level of Inhibin A were evaluated in patients and the control group. The level of tumor marker M2-PK was significantly higher in the group with hyperplastic polyps and colon cancer (P < .001) than in the control group. At the same time, there was no significant difference in Inhibin A level (P = .054). In the hyperplastic polyps group 73% and in the colorectal cancer group 27% had a positive immunochemical fecal occult blood (IFOBT) result, significantly higher than the control group (P < .001). Evaluation of the level of tumor marker M2-PK in the stool sample in association with the three-time iFOBT test method may be suggested as a quick and noninvasive method for screening and diagnosis of polyps and early stages of colon cancer.

Prenatal Diagnosis of Congenital Heart Diseases and Associations with Serum Biomarkers of Aneuploidy: A Multicenter Prospective Cohort Study

PURPOSE

We assessed prenatal detection rates of congenital heart disease (CHD) and associations between maternal serum biomarkers and non-chromosomal CHD in singleton pregnancies.

MATERIALS AND METHODS

This study was conducted as a secondary analysis of data obtained during a multicenter prospective cohort study that investigated the cost-effectiveness of prenatal testing for fetal aneuploidy. We analyzed the prenatal detection rate and accuracy for CHD screening via ultrasound during the second trimester, as well as associations between serum biomarkers and CHDs, in singleton newborns without chromosomal abnormalities.

RESULTS

Among 6715 women, 142 (2.1%) newborns were born with CHDs, of which 67 (1.0%) newborns had major CHDs. The prenatal detection rate for all CHDs and major CHDs were 34.5% and 58.2%, respectively. After excluding isolated ventricular septal defects, the detection rate for critical CHDs was 85.9%. Women with low pregnancy-associated plasma protein A (PAPP-A) (<0.4 multiples of the median, MOM) face increased risks of non-chromosomal CHDs [adjusted odds ratio (aOR) 2.76; 95% confidence interval (CI) 1.36-5.13] and major CHDs (aOR 7.30; 95% CI 3.18-15.59), compared to those without CHDs. A higher inhibin A level (≥2.5 MOM; aOR 4.84; 95% CI 1.42-12.46) was associated with non-chromosomal major CHDs.

CONCLUSION

Ultrasonography performed during the second trimester by obstetricians detected over 85% of critical CHDs. Low maternal serum PAPP-A or high inhibin-A was associated with non-chromosomal CHDs. These results may contribute to an improvement in prenatal diagnosis of CHDs.

Inflammatory Markers in Uterine Lavage Fluids of Pregnant, Non-Pregnant, and Intrauterine Device Implanted Mares on Days 10 and 15 Post Ovulation

Simple Summary

While intrauterine devices (IUDs) are used to prevent disturbing oestrous behaviour in sport mares, their mechanism of action has not been elucidated. The presence of an embryo or an IUD prevents cyclooxygenase-2 (COX-2) and subsequently prostaglandin (PG) release and luteolysis. It has been suggested that a plastic sphere would mimic the embryo by mechanotransduction. However, there is some evidence that IUDs also cause endometrial inflammation, which might contribute to luteostasis. The aim of this study was to investigate the presence and time course of possible inflammation by evaluating changes in uterine fluid composition. On Day 10 after ovulation, events leading to COX-2 and prostaglandin F_2α (PGF_2α) inhibition start, whereas either luteolysis occurs or the corpus luteum is maintained on Day 15. Therefore, uterine lavage fluid was evaluated at two time points in inseminated mares, either pregnant or not, and in mares inserted with an IUD. On Day 10, PGF_2α concentration in the fluid was significantly lower in the IUD group than in the pregnant mare one but did not differ from the non-pregnant mare group. On Day 15, the IUD group had significantly higher levels of the modulatory cytokine IL-10 and inhibin A, which could indicate previous inflammation and resolution stage.

Abstract

Intrauterine devices (IUDs) are used in mares to suppress oestrous behaviour, but the underlying mechanism is yet to be elucidated. The presence of an embryo or an IUD prevents cyclooxygenase-2 (COX-2) and, subsequently, prostaglandin (PG) release and luteolysis. However, inflammation may also be involved. Endometrial inflammatory markers in uterine lavage fluid were measured on Day 10 (EXP 1, n = 25) and Day 15 (EXP 2, n = 27) after ovulation in inseminated mares, non-pregnant or pregnant, and in mares in which a small plastic sphere had been inserted into the uterus 4 (EXP 1) or 3 days (EXP 2) after ovulation. Uterine lavage fluid samples were analysed for nitric oxide (NO), prostaglandin E₂ (PGE₂) (only EXP 1), prostaglandin F_2α (PGF_2α), inhibin A and cytokines, and blood samples for progesterone and oestradiol. On Day 10, the concentration of PGF_2α was lower (p < 0.05) in the IUD group than in pregnant mares. The concentration of the modulatory cytokine IL-10 was significantly higher in the IUD group in comparison to non-pregnant mares, and inhibin A was significantly higher in IUD mares than in the pregnant counterparts on Day 15. The results suggest that the presence of IUD causes endometrial inflammation which is at a resolution stage on Day 15.

Correlation between serum markers in the second trimester and preterm birth before 34 weeks in asymptomatic twin pregnancies

OBJECTIVE

To determine the correlation between the levels of serum markers in the second trimester and preterm birth before 34 weeks in asymptomatic twin pregnancies.

METHODS

We conducted a retrospective review of the medical records of 102 asymptomatic twin pregnancies delivered at Chilgok Kyungpook National University Hospital between March 2014 and February 2020. Participants were divided into two groups, based on delivery before and after 34 weeks of gestation. Results of the quad test performed at 15-18 weeks and the complete blood count done at 24-28 weeks were compared.

RESULTS

Preterm birth before 34 weeks of pregnancy was associated with higher levels of maternal α-fetoprotein (1.04 vs 0.98, multiple of median [MoM], P = 0.006), human chorionic gonadotropin (1.76 vs 1.31, MoM, P = 0.000), and inhibin A (1.78 vs 1.04, MoM, P = 0.000). Positive correlations were observed between gestational age at delivery and white blood cell (WBC) markers. Women with preterm delivery had decreased WBC counts (8180 vs 9405 × 10³ /µl, P = 0.019) and neutrophil:lymphocyte ratios (3.85 vs 4.92, P = 0.001).

CONCLUSION

Serum marker levels in the second trimester can be indicators of preterm delivery before 34 weeks in asymptomatic twin pregnancies.

Interactions between serum FSH, inhibin B and antral follicle count in the decline of serum AMH during the menstrual cycle in late reproductive age

Objective

To investigate the hormonal interrelationships during the menstrual cycle in women of late reproductive age with suppressed serum AMH and antral follicle count (AFC).

Methods

Serum hormones (AMH, FSH, LH, estradiol, progesterone, inhibin A, inhibin B), AFC (2-10 mm) and AMH/AFC ratio (an estimate of AMH/follicle) were assessed every 2-3 days across the menstrual cycle in 26 healthy ovulatory women aged 18-50 years.

Results

An 11-fold fall in AMH/AFC was observed in women aged ≥45 years compared to those 18-45 years (P < .001). Although women ≥45 years exhibited normal menstrual cycle patterns of serum estradiol, progesterone, LH and inhibin A, FSH was elevated (P < .001) and inhibin B suppressed (P < .001) compared to the younger group. Overall FSH was inversely correlated (r = .55, P < .05) and AMH directly correlated (r = .88, P < .01) with AFC; however, these relationships were curvilinear and more pronounced when AFC was low. Inhibin B was directly linearly correlated (r = .70, P < .01) with AFC across both high and low AMH/follicle groups.

Conclusions

It is hypothesized that the marked fall in AMH/follicle in late reproductive age is attributed to the change in the hormonal interplay between the pituitary and ovary. The fall in AFC leads to a decrease in inhibin B and a concomitant increase in FSH by a recognized feedback mechanism. It is postulated the elevated FSH suppresses AMH either directly or indirectly through oocyte-specific growth factors leading to a marked fall in AMH/follicle. We propose that pituitary-ovarian and intra-ovarian regulatory systems underpin the accelerated fall in AMH/follicle during the transition to menopause.

Predictive value of quad serum markers for adverse pregnancy outcome in antiphospholipid antibody syndrome

PURPOSE

We investigated the validity of quad serum markers for the prediction of adverse pregnancy outcome (APO) in women with antiphospholipid antibody syndrome (APS).

METHODS

We included 75 women with APS delivered at our institution. APO was defined as stillbirth, small for gestational age (SGA), severe preeclampsia, or preterm delivery. First, we compared clinical characteristics between patients with or without composite APO. Second, we compared the rate of APO according to abnormal level of quad serum markers. Lastly, receiver operating characteristic (ROC) curve analysis was performed.

RESULTS

APS mothers with APO showed higher median α-fetoprotein (AFP) and inhibin A compared with those without APO. They were also associated with higher rates of positive risk of Down syndrome and neural tube defect. Elevated AFP, human chorionic gonadotropin (hCG), and inhibin A level was associated with higher rates of stillbirth, SGA, preterm delivery, and composite APO. ROC curve for prediction of stillbirth revealed an area under the curve of 0.835 for AFP, 0.781 for hCG, and 0.932 for inhibin A. For composite APO, the area under the ROC curve was 0.692 for AFP and 0.810 for inhibin A.

CONCLUSION

Elevated AFP, hCG, and inhibin A in women with APS demonstrated a high predictive value for APO, especially stillbirth.

Serum markers in quadruple screening associated with adverse pregnancy outcomes: A case-control study in China

BACKGROUND

We assessed whether the results of quadruple screening during pregnancy are associated with an increased risk of adverse pregnancy outcomes.

METHODS

We measured serum marker concentrations using quadruple screening in the second trimester of pregnancy and analyzed the relationship between adverse perinatal outcomes and serum markers in 12,124 pregnant women. A multivariate logistic regression analysis was used to evaluate the relative risk of quadruple screening and adverse pregnancy outcomes.

RESULTS

Compared with the control group, increased concentrations of alpha-fetoprotein (AFP) and inhibin A were risk factors for preeclampsia and preterm delivery; low concentrations of unconjugated estriol and high inhibin A were risk factors for pregnancy hypertension; an increased concentration of human chorionic gonadotropin (hCG) was a risk factor for gestational diabetes mellitus; high AFP, low hCG, and high inhibin A were risk factors for low birth weight; and low AFP and high hCG were risk factors for macrosomia.

CONCLUSIONS

Quadruple screening in the second trimester of pregnancy can provide early warning signs for maternal and fetal adverse pregnancy outcomes.

PAPP-A2 and Inhibin A as Novel Predictors for Pregnancy Complications in Women With Suspected or Confirmed Preeclampsia

Background

We aimed to evaluate the value of inhibin A and PAPP‐A2 (pregnancy‐associated plasma protein‐A2) as novel biomarkers in the prediction of preeclampsia‐related complications and how they compare with angiogenic biomarkers.

Methods and Results

Making use of a secondary analysis of a prospective, multicenter, observational study, intended to evaluate the usefulness of sFlt‐1 (soluble Fms‐like tyrosine kinase‐1)/PlGF (placental growth factor) ratio, we measured inhibin A and PAPP‐A2 levels in 524 women with suspected/confirmed preeclampsia. Women had a median gestational age of 35 weeks (range, 20–41 weeks) while preeclampsia occurred in 170 (32%) women. Levels of inhibin A and PAPP‐A2 were significantly increased in women with preeclampsia and in maternal perfusate of preeclamptic placentas. Inhibin A and PAPP‐A2 (C‐index = 0.73 and 0.75) significantly improved the prediction of maternal complications when added on top of the traditional criteria; gestational age, parity, proteinuria, and diastolic blood pressure (C‐index = 0.60). PAPP‐A2 was able to improve the C‐index from 0.75 to 0.77 when added on top of the sFlt‐1/PlGF ratio for the prediction of maternal complications. To discriminate fetal/neonatal complications on top of traditional criteria, inhibin A and PAPP‐A2 showed additive value (C‐index = 0.79 to 0.80 and 0.82, respectively) but their discriminative ability remained inferior to that of sFlt‐1/PlGF ratio or PlGF. Interestingly, the PAPP‐A2/PlGF ratio alone showed remarkable value to predict pregnancy complications, being superior to sFlt‐1/PlGF ratio in the case of maternal complications.

Conclusions

Inhibin A and PAPP‐A2 show significant potential to predict preeclampsia‐related pregnancy complications and might prove beneficial on top of the angiogenic markers.

Effects of Inhibin A on Apoptosis and Proliferation of Bovine Granulosa Cells

Inhibin A is well known for its inhibitory properties against follicle-stimulating hormone (FSH), released through a pituitary-gonadal negative feedback loop to regulate follicular development. Ovarian folliculogenesis, hormonal biosynthesis, and gametogenesis are dependent on inhibins, playing vital roles in promoting or inhibiting cell proliferation. The present study explored the physiological and molecular response of bovine granulosa cells (GCs) to different concentrations of inhibin A in vitro. We treated the primary GCs isolated from ovarian follicles (3-6 mm) with different levels of inhibin A (20, 50, and 100 ng/mL) along with the control (0 ng/mL) for 24 h. To evaluate the impact of inhibin A on GCs, several in vitro cellular parameters, including cell apoptosis, viability, cell cycle, and mitochondrial membrane potential (MMP) were detected. Besides, the transcriptional regulation of pro-apoptotic (BAX, Caspase-3) and cell proliferation (PCNA, CyclinB1) genes were also quantified. The results indicated a significant (p < 0.05) increase in the cell viability in a dose-dependent manner of inhibin A. Likewise, MMP was significantly (p < 0.05) enhanced when GCs were treated with high doses (50, 100 ng/mL) of inhibin A. Furthermore, inhibin A dose (100 ng/mL) markedly improved the progression of the G1 phase of the cell cycle and increased the cell number in the S phase, which was supported by the up-regulation of the proliferating cell nuclear antigen PCNA (20, 50, and 100ng/mL) and CyclinB (100 ng/mL) genes. In addition, higher doses of inhibin A (50 and 100 ng/mL) significantly (p < 0.05) decreased the apoptotic rate in GCs, which was manifested by down regulating BAX and Caspase-3 genes. Conclusively, our study presented a worthy strategy for the first time to characterize the cellular adaptation of bovine GCs under different concentrations of inhibin A. Our results conclude that inhibin A is a broad regulatory marker in GCs by regulating apoptosis and cellular progression.

Endometrial development during the transition to menopause: preliminary associations with follicular dynamics

Objective: This study aimed to test the hypothesis that the development of functional luteal phase dominant follicles (LPDFs) is associated with increased endometrial growth as women transition to menopause.Methods: Endometrial thickness (ET), follicle development, and hormone production were characterized in ovulatory women of mid-reproductive age (MRA; 18-35 years, n = 10) and advanced reproductive age (ARA; 45-55 years, n = 16). Transvaginal ultrasonography was conducted every 1-3 days during one interovulatory interval to quantify ET and the diameters of follicles ≥2 mm. Blood was drawn at each visit to measure progesterone, estradiol, inhibin A, follicle stimulating hormone, and luteinizing hormone.Results: In the MRA group, ET was lower (8.87 vs. 10.1 mm) in women with typical versus no LPDFs, in association with greater luteal phase estradiol (91.1 vs. 48.8 ng/l). In the ARA group, luteal phase endometrial growth was greater (12.0 vs. 10.4 mm) in women with typical versus no LPDFs, in association with lower progesterone (10.7 vs. 13.8 μg/l; LPDF effect p < 0.1) and inhibin A (35.6 vs. 51.17 ng/l; p < 0.10).Conclusions: Preliminary findings suggest that ET may be increased in women who develop LPDFs, in association with reduced luteal phase progesterone and inhibin A, during the transition to menopause. Continued research is required to confirm these findings.

A preeclampsia risk prediction model based on maternal characteristics and serum markers in twin pregnancy

Aim: To develop preeclampsia (PE) risk prediction model based on maternal characteristics and serum markers at the first and second trimester in the twin pregnancy.Methods: Between January 2005 and September 2017, we retrospectively reviewed medical records of 532 twin pregnant women who underwent maternal serum integrated test and gave birth at a Bundang CHA Medical Center. Maternal serum pregnancy-associated plasma protein A (PAPP-A) was determined at 10⁺⁰ to 13⁺⁶ weeks and the serum alpha-fetoprotein (MSAFP), human chorionic gonadotrophin (hCG), unconjugated estriol (uE₃) and inhibin A were assayed at 14⁺⁰ to 22⁺⁰weeks. We assessed the relationships of maternal characteristics and serum markers by using multiple logistic regression analysis.Results: The study included 35 patients who diagnosed PE and a control group consisting of the other 497 patients in twin pregnancy. There were no significant differences in the maternal age and body mass index (BMI) between two groups. However, the gestational age and placenta weight at delivery were significantly different between groups (p < .001, p = .005, respectively. Among the maternal serum markers, inhibin A value was significantly higher in women with PE compared to those without preeclampsia (p < .001). In addition, we predicted the PE using maternal age, BMI, uE₃, and inhibin A which were achieving an area under the curve of 0.73 overall in twin pregnancy.Conclusion: A risk prediction model of PE which combined maternal age, BMI, uE₃, and inhibin A was better early predictors than any individual marker twin pregnancy.

Determination of insulin resistance and its relationship with hyperandrogenemia,anti-Müllerian hormone, inhibin A, inhibin B, and insulin-like peptide-3 levels in adolescent girls with polycystic ovary syndrome

Background/aim

This study aims to investigate the association between polycystic ovary syndrome (PCOS) and obesity and insulin resistance (IR) with respect to anti-Müllerian hormone (AMH), inhibin A (INH-A), inhibin B (INH-B), and insulin-like peptide 3 (INSL3) levels, all factors which may have an impact on IR.

Materials and methods

In this cross sectional study, 52 adolescent girls diagnosed with PCOS[groups: nonobese (NO), n = 23; overweight/obese (OW/O), n = 29] were included. Blood samples were obtained to measure AMH, INH-B, INH-A, and INSL3 levels, together with hormonal and biochemical assessments. Oral glucose tolerance test (OGTT) was performed and the indexes of IR [homeostasis model assessment: insulin resistance (HOMA-IR) and Matsuda index] were calculated.

Results

Insulin resistance was 56.5% with OGTT and 30.4% with HOMA-IR in nonobese-PCOS girls. There was a correlation between INH-A and HOMA-IR even when controlled for body mass index (BMI). INH-B and FAI also had correlations with HOMA-IR which disappeared when controlled for BMI. In regression analyses, AMH (odds ratio = [0.903, P = 0.015) and FAI (odds ratio = 1.353, P = 0.023) are found to be contributors to IR. Their effect was BMI-independent. In ROC analysis, the cutoff value for FAI was 5.93 (sensitivity 71%) to define IR in PCOS girls.

Conclusion

AMH and FAI may contribute to IR (defined by OGTT) in PCOS. FAI might be used as a supporting IR marker (defined by OGTT) in adolescent girls with PCOS.

Prepubertal gynaecomastia in a boy with Peutz-Jeghers syndrome: managing the aromatase overexpression

Background Gynaecomastia, although rarely related to testicular tumours, in boys with Peutz-Jeghers syndrome (PJS) usually occurs due to large-cell calcifying Sertoli cell tumour (LCCSCT). Case presentation A 4-year-old boy, with a genetic diagnosis of PJS, presented gynaecomastia since the age of 2, associated with increased height velocity (HV). He exhibited bilateral breast enlargement (Tanner-B4) and a testicular volume of 4 mL. Testicular ultrasound revealed multifocal microcalcifications in both testicles. A laboratory evaluation showed undetectable gonadotrophins, testosterone and oestrogen and inhibin A of 4.6 pg/mL (0.9-1.7). The boy was subjected to therapy with anastrozole. In the last follow-up, 2 years after the start of therapy, he experienced a less tense Tanner-B2 and a decrease in HV; serum inhibin A had become negative. Conclusions This is one of the most precocious PJS-related gynaecomastia treated with aromatase inhibitors (AIs) reported in the literature. Oestrogen levels, although under the detection limit, may be sufficient to stimulate breast tissue/growth plates. Inhibin A is a good marker of LCCSCT and an indicator of response to AIs.

HIF1A and EPAS1 potentiate hypoxia-induced upregulation of inhibin alpha chain expression in human term cytotrophoblasts in vitro

Study Question

Are hypoxia-inducible factors (HIF) responsible for the potentiation of inhibin alpha subunit (INHA) gene expression in primary cultures of human term cytotrophoblasts under low-oxygen tension?

Summary Answer

Both HIF1A and endothelial PAS domain protein 1 (EPAS1) are involved in the potentiation of INHA gene upregulation in cytotrophoblasts cultured under hypoxia.

What Is Known Already

During the in vitro differentiation of cytotrophoblasts into syncytiotrophoblasts under 21% O2, INHA expression increases. This expression is further increased when cells are cultured under low-oxygen tension (e.g. 2.5% O2). Moreover, in pregnancy-related diseases, such as pre-eclampsia or intrauterine growth restriction (IUGR), in which hypoxia is suspected to be responsible for the abnormal placental development, maternal serum concentration of inhibin A is elevated.

Study Design, Size, Duration

Cytotrophoblasts were isolated and purified from human term placentas (n = 6). Cells were cultured under 21% O2, and allowed to differentiate for 48 h. A first group of cells was treated for 16 h under 21% O2 with dimethyloxalylglycine (DMOG) or deferoxamine (DFX), molecules that mimic hypoxia by inhibiting HIF1 proteasomal degradation. Involvement of HIF1A and EPAS1 (also known as HIF2A), two HIF isoforms expressed in trophoblasts, was shown by treating another group of cells cultured under 2.5% O2 with specific inhibitors of HIF1A and EPAS1 for 16 h. INHA mRNA expression was assessed by real-time PCR and secreted inhibin A was quantified by ELISA. The role of HIF1A and EPAS1 in INHA transcriptional regulation was further confirmed by cotransfecting primary cytotrophoblasts with a luciferase reporter plasmid containing a 3.9 kb INHA promoter and plasmids allowing overexpression of HIF1A and EPAS1.

Participants/Materials, Setting, Methods

Placentas were obtained after vaginal or elective cesarean delivery from uncomplicated pregnancies at term (n≥ 4). The methods used were hormone measurements in the cell supernatants by enzyme-linked immunosorbent assay, real-time quantitative PCR, western blotting, immunofluorescence microscopy and transient transfection.

Main Results and the Role of Chance

HIF1 protein stabilization with DMOG and DFX increased 21% O2-induced INHA mRNA and protein upregulation (P < 0.05 versus control), while hypoxia-induced INHA upregulation was repressed by HIF1A and EPAS1 inhibitors (P < 0.05 versus control). In transfection experiments of primary term cytotrophoblasts, cloned INHA promoter transcriptional activity was increased by 2.5% O2 compared to 21% O2 (P < 0.05). Overexpression of both HIF1A and EPAS1 under 21% O2 increased cloned INHA transcriptional activity (P < 0.001 versus control).

Large Scale Data

Not applicable.

Limitations, Reasons for Caution

HIF1A and EPAS1 may regulate INHA expression by binding to an hypoxia-responsive element within the promoter, but we were unable to identify such an element. Inhibition of HIF1A and EPAS1 did not completely suppress upregulation of INHA expression suggesting that other transcription factors, not identified or studied here, are involved.

Wider Implications of the Findings

Our data suggest that the effect of HIF1 proteins on INHA gene promoter activity may be indirect. By demonstrating the role of HIF1A and especially EPAS1 in INHA gene upregulation under hypoxia, the results suggest that HIF1 proteins may become new therapeutic targets in the treatment of pregnancy-related diseases such as pre-eclampsia or IUGR.

Study Funding/Competing Interest(s)

This work was fully supported by 'Fetus for Life' charity. C. Depoix was supported by a fellowship 'Fonds de Recherche Clinique' from 'Fondation Saint-Luc', Belgium. The authors declare that there is no conflict of interest regarding the publication of this paper.

Inhibin A and inhibin B producing ovarian fibrothecoma revealed by suppression of follicle stimulating hormone (FSH) in a post-menopausal woman: report of the first case

In this report, we describe the first case ever reported in the literature, of an inhibin-A (INHA) and inhibin-B (INHB) producing fibrothecoma. A post-menopausal woman was referred to our unit because of follicle stimulating hormone (FSH) level below the reference interval for postmenopausal women. By contrast luteinizing hormone, hCG, and estradiol levels were within normal range. This discrepancy suggested the secretion of FSH inhibitory factors. INHB and INHA levels were markedly elevated for age, 475 pg/mL and 100 pg/mL, respectively. Ultrasonography and MRI showed a pelvic mass of indeterminate nature. Abnormal inhibin secretion is generally observed in granulosa cell tumors. In this case this etiology was unlikely because of low estradiol and AMH levels. Surgical exploration revealed a 10 cm mass of the left ovary proven histologically to be an ovarian fibrothecoma (OFT). After tumor removal, INHB and INHA levels decreased rapidly. Only three cases of OFT with an important secretion of INHB have been reported to date. INHA secretion has never been associated with OFT. There is a need to develop coupled hormone and imaging strategies to diagnose the source of INH secretion in case of FSH/LH discrepancy.

Serum biomarkers combined with uterine artery Doppler in prediction of preeclampsia

First-trimester screening may be a major advantage over a second-trimester approach since it opens prospects for early and more efficient interventions. The aim of the current study was to evaluate whether the measurement of maternal serum inhibin A, activin A and placental growth factor (PlGF) at three to four months gestation with the second-trimester uterine artery pulsatility index (PI) are useful in predicting preeclampsia in a group of nulliparous women. All the patients also underwent uterine artery Doppler examination to measure the PI at 22–24 weeks gestation. Inhibin A, activin A and PlGF were measured using an ELISA by an examiner who was blinded to the pregnancy outcome. Thirty-eight cases with preeclampsia and 100 controls were analyzed. Second-trimester uterine artery PI and marker levels were expressed as multiples of the median (MoM). The uterine artery PI was increased in pregnancies with preeclampsia compared with controls. In pregnancies that developed preeclampsia, the uterine artery PI was increased (1.61±0.047 vs. 1.02±0.049, P<0.001), as was the level of inhibin A (1.72±0.023 vs. 1.03±0.063, P<0.001) and the level of activin A (1.68±0.38 vs. 1.06±0.42, P<0.001) compared with the controls. In contrast, the level of PlGF was decreased in pregnancies that developed preeclampsia compared with the controls (0.69±0.23 vs. 1.00±0.26, P<0.001). A combination of activin A, PlGF and uterine artery PI gave an AUC of 0.915 (95% CI, 0.812–0.928; P<0.001) with a sensitivity of 91% at a specificity of 82%. In our study, we demonstrated that both serum inhibin A and activin A levels were increased, while the PlGF level was decreased in the early second-trimester in women who developed preeclampsia.

Activation of endocrine-related gene expression in placental choriocarcinoma cell lines following DNA methylation knock-down

Increasingly, placental DNA methylation is assessed as a factor in pregnancy-related complications, yet the transcriptional impact of such findings is not always clear. Using a proliferative in vitro placental model, the effect of DNA methylation loss on gene activation was evaluated at a number of genes selected for being differentially methylated in pre-eclampsia-associated placentae in vivo. We aimed to determine whether reduced DNA methylation at specific loci was associated with transcriptional changes at the corresponding gene, thus providing mechanistic underpinnings for previous clinical findings and to assess the degree of transcriptional response amongst our candidate genes. BeWo and JEG3 choriocarcinoma cells were exposed to 1 μM 5-Aza-2'-deoxycytidine (5-Aza-CdR) or vehicle control for 48 h, and re-plated and cultured for a further 72 h in normal media before cells were harvested for RNA and DNA. Bisulphite pyrosequencing confirmed that DNA methylation was reduced by ∼30-50% points at the selected loci studied in both cell lines. Gene activation, measured by qRT-PCR, was highly variable and transcript specific, indicating differential sensitivity to DNA methylation. Most notably, loss of DNA methylation at the leptin (LEP) promoter corresponded to a 200-fold and 40-fold increase in LEP expression in BeWo and JEG3 cells, respectively (P < 0.01). Transcripts of steroidogenic pathway enzymes CYP11A1 and HSD3B1 were up-regulated ∼40-fold in response to 5-Aza-CdR exposure in BeWo cells (P < 0.01). Other transcripts, including aromatase (CYP19), HSD11B2, inhibin (INHBA) and glucocorticoid receptor (NR3C1) were more moderately, although significantly, affected by loss of associated DNA methylation. These data present a mixed effect of DNA methylation changes at selected loci supporting cautionary interpretation of DNA methylation results in the absence of functional data.