Androgens in the maternal and fetal circulation: association with insulin resistance

Associations of per- and polyfluoroalkyl substances with maternal early second trimester sex-steroid hormones

BACKGROUND/AIMS

Pregnant women are exposed to persistent environmental contaminants, including per- and polyfluoroalkyl substances (PFAS) that disrupt thyroid function. However, it is unclear if PFAS alter maternal sex-steroid hormone levels, which support pregnancy health and fetal development.

METHODS

In Illinois women with relatively high socioeconomic status (n = 460), we quantified perfluorononanoic (PFNA), perfluorooctane sulfonic (PFOS), perfluorooctanoic (PFOA), methyl-perfluorooctane sulfonamide acetic acid, perfluorohexanesulphonic (PFHxS), perfluorodecanoic (PFDeA), and perfluoroundecanoic (PFUdA) acid concentrations in fasting serum samples at median 17 weeks gestation, along with plasma progesterone, testosterone, and estradiol. We evaluated covariate-adjusted associations of ln-transformed hormones with each ln-transformed PFAS individually using linear regression and with the PFAS mixture using quantile-based g-computation (QGComp).

RESULTS

Interquartile range (IQR) increases in PFOS were associated with higher progesterone (%Δ 3.0; 95%CI: -0.6, 6.6) and estradiol (%Δ: 8.1; 95%CI: 2.2, 14.4) levels. Additionally, PFHxS was positively associated with testosterone (%Δ: 10.2; 95%CI: 4.0, 16.7), whereas both PFDeA and PFUdA were inversely associated with testosterone (%Δ: -5.7; 95%CI: -10.3, -0.8, and %Δ: -4.1; 95%CI: -7.6, -0.4, respectively). The IQR-standardized PFAS mixture was not associated with progesterone (%Δ: 1.6; 95%CI: -5.8, 9.2), due equal partial positive (%Δ: 9.2; driven by PFOA) and negative (%Δ: -7.4; driven by PFOS) mixture associations. Similarly, the mixture was not associated with testosterone (%Δ: 5.3; 95%CI: -9.0, 20.1), due to similar partial positive (%Δ: 23.6; driven by PFHxS) and negative (%Δ: -17.4; driven by PFDeA) mixture associations. However, we observed a slightly stronger partial positive (%Δ: 25.6; driven by PFOS and PFUdA) than negative (%Δ: -16.3; driven by PFOA) association resulting in an overall non-significant positive trend between the mixture and estradiol (%Δ: 8.5; 95%CI: -3.7, 20.9).

CONCLUSION

PFAS mixture modeled using QGComp was not associated with maternal sex-steroid hormones due to potential opposing effects of certain PFAS. Additional prospective studies could corroborate these findings.

Associations of urinary non-persistent endocrine disrupting chemical biomarkers with early-to-mid pregnancy plasma sex-steroid and thyroid hormones

BACKGROUND/OBJECTIVES

Pregnant women are exposed to numerous endocrine disrupting chemicals (EDCs) that can affect hormonal pathways regulating pregnancy outcomes and fetal development. Thus, we evaluated overall and fetal sex-specific associations of phthalate/replacement, paraben, and phenol biomarkers with sex-steroid and thyroid hormones.

METHODS

Illinois women (n = 302) provided plasma for progesterone, estradiol, testosterone, free T4 (FT4), total T4 (TT4), and thyroid stimulating hormone (TSH) at median 17 weeks gestation. Women also provided up-to-five first-morning urine samples monthly across pregnancy (8-40 weeks), which we pooled to measure 19 phthalate/replacement metabolites (reflecting ten parent compounds), three parabens, and six phenols. We used linear regression to evaluate overall and fetal sex-specific associations of biomarkers with hormones, as well as weighted quantile sum and Bayesian kernel machine regression (BKMR) to assess cumulative associations, non-linearities, and chemical interactions.

RESULTS

In women of relatively high socioeconomic status, several EDC biomarkers were associated with select hormones, without cumulative or non-linear associations with progesterone, FT4, or TT4. The biomarker mixture was negatively associated with estradiol (only at higher biomarker concentrations using BKMR), testosterone, and TSH, where each 10% mixture increase was associated with -5.65% (95% CI: -9.79, -1.28) lower testosterone and -0.09 μIU/mL (95% CI: -0.20, 0.00) lower TSH. Associations with progesterone, testosterone, and FT4 did not differ by fetal sex. However, in women carrying females, we identified an inverted u-shaped relationship of the mixture with estradiol. Additionally, in women carrying females, each 10% increase in the mixture was associated with 1.50% (95% CI: -0.15, 3.18) higher TT4, whereas in women carrying males, the mixture was associated with -1.77% (95% CI: -4.08, 0.58) lower TT4 and -0.18 μIU/mL (95% CI: -0.33, -0.03) lower TSH. We also identified select chemical interactions.

CONCLUSION

Some biomarkers were associated with early-to-mid pregnancy hormones. There were some sex-specific and non-linear associations. Future studies could consider how these findings relate to pregnancy/birth outcomes.

Association between sex steroid hormones and subsequent hyperglycemia during pregnancy

Objective

Sex steroid hormones may play a role in insulin resistance and glucose dysregulation. However, evidence regarding associations between early-pregnancy sex steroid hormones and hyperglycemia during pregnancy is limited. The primary objective of this study was to assess the relationships between first trimester sex steroid hormones and the subsequent development of hyperglycemia during pregnancy; with secondary evaluation of sex steroid hormones levels in mid-late pregnancy, concurrent with and subsequent to diagnosis of gestational diabetes.

Methods

Retrospective analysis of a prospective pregnancy cohort study was conducted. Medically low-risk participants with no known major endocrine disorders were recruited in the first trimester of pregnancy (n=319). Sex steroid hormones in each trimester, including total testosterone, free testosterone, estrone, estradiol, and estriol, were assessed using high-performance liquid chromatography and tandem mass spectrometry. Glucose levels of the 1-hour oral glucose tolerance test and gestational diabetes diagnosis were abstracted from medical records. Multivariable linear regression models were fitted to assess the associations of individual first trimester sex steroids and glucose levels.

Results

In adjusted models, first trimester total testosterone (β=5.24, 95% CI: 0.01, 10.46, p=0.05) and free testosterone (β=5.98, 95% CI: 0.97, 10.98, p=0.02) were positively associated with subsequent glucose concentrations and gestational diabetes diagnosis (total testosterone: OR=3.63, 95% CI: 1.50, 8.78; free testosterone: OR=3.69; 95% CI: 1.56, 8.73). First trimester estrone was also positively associated with gestational diabetes (OR=3.66, 95% CI: 1.56, 8.55). In mid-late pregnancy, pregnant people with gestational diabetes had lower total testosterone levels (β=-0.19, 95% CI: -0.36, -0.02) after adjustment for first trimester total testosterone.

Conclusion

Early-pregnancy sex steroid hormones, including total testosterone, free testosterone, and estrone, were positively associated with glucose levels and gestational diabetes in mid-late pregnancy. These hormones may serve as early predictors of gestational diabetes in combination with other risk factors.

Longer anogenital distance in female fetus of diabetic and obese pregnant women

OBJECTIVE

Previous studies revealed that prenatal exposure to androgen excess such as polycystic ovary syndrome (PCOS) is associated with offspring's anogenital distance (AGD) length, and AGD is a biomarker of intrauterine androgen exposure. This study aims to investigate a possible relationship of fetal AGD with maternal diabetes and obesity, and to evaluate whether AGD predicts the fetal androgen exposure related to diabetes and obesity in female fetus. This study is the first to focus on the relationship between offspring's AGD and maternal diabetes and obesity.

MATERIALS AND METHODS

This is a prospective study investigating 218 pregnant women (125 in control group and 93 in study group). Fetal AGD was measured from the center of anus to the posterior convergence of the fourchette by ultrasound. Multivariate linear regression analysis was applied to assess the association of the fetal AGD length with maternal diabetes and obesity.

RESULTS

The control patients had significantly shorter fetal AGD (mean:10.7 mm, P < 0.001) compared to diabetic, obese and diabetic obese patients (mean: 12.6 mm, 12.8 mm and 12.9 mm, respectively). The results of regression analysis showed that both maternal diabetes and obesity were significantly correlated with longer AGD in female fetus. The results confirmed also that offspring's AGD measurement in utero by ultrasound is feasible and reliable.

CONCLUSION

The study findings suggest that both maternal diabetes and obesity are associated with intrauterine androgenic milieu during pregnancy, and fetal AGD may be used as a biomarker to predict this effect. This may provide important advantages in terms of early detection of reproductive system abnormalities related to prenatal androgen exposure.

Characterization of trophoblast mitochondrial function and responses to testosterone treatment in ACH-3P cells

INTRODUCTION

Trophoblast mitochondria play important roles in placental energy metabolism, physiology and pathophysiology. Hyperandrogenism has been associated with mitochondrial abnormalities in pregnancy disorders such as pre-eclampsia, gestational diabetes, and intrauterine growth restriction, but the direct impacts of androgen exposure on placental mitochondrial function are unknown. Given the inherent limitations of studying the human placenta during pregnancy, trophoblast cell lines are routinely used to model placental biology in vitro. The aim of this study was to characterize mitochondrial respiratory function in four commonly used trophoblast cell lines to provide a basis for selecting one well-suited to investigating the impact of androgens on trophoblast mitochondrial function.

METHODS

Androgen receptor expression, mitochondrial respiration (JO₂) and reactive oxygen species (ROS) release rates were evaluated in three human trophoblast cell lines (ACH-3P, BeWo and Swan-71) and one immortalized ovine trophoblast line (iOTR) under basal and substrate-stimulated conditions using high-resolution fluorespirometry.

RESULTS

ACH-3P cells exhibited the greatest mitochondrial respiratory capacity and coupling efficiency of the four trophoblast lines tested, along with robust expression of androgen receptor protein that was found to co-localize with mitochondria by immunoblot and immunofluorescence. Acute testosterone administration (10 nM) tended to decrease ACH-3P mitochondrial JO₂ and increase ROS release, while chronic (7 days) testosterone exposure increased expression of mitochondrial proteins, JO₂, and ROS release.

DISCUSSION

These studies establish ACH-3P as a suitable cell line for investigating trophoblast mitochondrial function, and provide foundational evidence supporting links between hyperandrogenism and placental mitochondrial ROS production with potential relevance to several common pregnancy disorders.

Association between prenatal androgens and cord blood androgens, a path analysis

To determine association paths between prenatal androgens and cord blood androgens. The concentrations of T, FT, DHT, DHEA and SHBG in prenatal venous blood and cord blood were measured in 342 pregnant women and their neonates. The association paths between these hormones in prenatal and cord blood were revealed using Pearson correlation, multiple linear regression and path analysis. CB-T, CB-FT and CB-DHT in male neonates were higher than those in female neonates. In male and female neonates, P-FT was lower than CB-FT; however, P-DHT and P-SHBG were higher than CB-DHT and CB-SHBG, respectively. P-DHEA was lower than CB-DHEA in female newborns. In male neonates, there were association paths of P-T → CB-T → CB-FT → CB-DHT, P-T → CB-FT → CB-DHT, P-T → P-FT → CB-FT → CB-DHT, P-T → P-DHT, CB-DHEA → CB-DHT, CB-DHEA → P-DHT, and CB-DHEA → P-DHEA. In female neonates, there were association paths of P-T → CB-T → CB-FT → CB-DHT, P-T → P-FT → CB-FT → CB-DHT, P-T → P-FT → P-DHT, P-T → P-DHT, P-DHEA → P-DHT, CB-DHEA → P-DHEA, and CB-DHEA → CB-FT. There were differences in the T, FT and DHT concentrations in cord blood between male and female neonates and in the FT, DHT, DHEA, and SHBG concentrations between prenatal and cord blood. P-T and P-FT concentrations were positively associated with CB-T and CB-FT concentrations, while CB-DHEA concentration was positively associated with P-DHEA concentration.

Sociodemographic and Biological Factors of Health Disparities of Mothers and Their Very Low Birth-Weight Infants

BACKGROUND

Black mothers and their very low birth-weight infants in the United States have increased risk of adverse neonatal and maternal health outcomes compared with White mothers and infants. Disparities in adverse birth outcomes associated with sociodemographic factors are difficult to quantify and modify, limiting their usefulness in assessing intervention effects.

PURPOSE

To test hypotheses that (1) the biological factors of maternal testosterone and cortisol are associated with sociodemographic factors and (2) both factors are associated with neonatal health and maternal mental health and healthy behaviors between birth and 40 weeks' gestational age.

METHODS

We used a descriptive, longitudinal design. Eighty-eight mothers and very low birth-weight neonates were recruited from a tertiary medical center in the United States. Data on sociodemographic factors and neonatal health were collected from medical records. Maternal mental health and healthy behaviors were collected with questionnaires. Maternal salivary testosterone and cortisol levels were measured using enzyme immunoassays. Data were analyzed primarily using general linear and mixed models.

RESULTS

High testosterone and/or low cortisol levels were associated with younger age, less education, enrollment in a federal assistance program, being unmarried, being Black, poorer neonatal health, and delayed physical growth. Low cortisol level was related to higher levels of depressive symptoms. Black mothers had fewer healthy behaviors than White mothers.

IMPLICATIONS FOR PRACTICE AND RESEARCH

Findings confirm that biological factors are associated with sociodemographic factors, and both are associated with neonatal health and maternal mental health and healthy behaviors. We propose using sociodemographic and biological factors concurrently to identify risk and develop and evaluate ante- and postpartum interventions.Video abstract available athttps://journals.na.lww.com/advancesinneonatalcare/Pages/videogallery.aspx?autoPlay=false&videoId=59.

Effect of maternal body mass index on the steroid profile in women with gestational diabetes mellitus

OBJECTIVE

To explore the effect of maternal body mass index (BMI) on steroid hormone profiles in women with gestational diabetes mellitus (GDM) and those with normal glucose tolerance (NGT).

METHODS

We enrolled 79 women with NGT and 80 women with GDM who had a gestational age of 24-28 weeks. The participants were grouped according to their BMI. We quantified 11 steroid hormones profiles by liquid chromatography-tandem mass spectrometry and calculated the product-to-precursor ratios in the steroidogenic pathway.

RESULTS

Women with GDM and BMI<25kg/m² showed higher concentrations of dehydroepiandrosterone (DHEA) (p<0.001), testosterone (T) (p=0.020), estrone (E1) (p=0.010) and estradiol (E2) (p=0.040) and lower Matsuda index and HOMA-β than women with NGT and BMI<25kg/m². In women with GDM, concentrations of E1 (p=0.006) and E2 (p=0.009) declined, accompanied by reduced E2/T (p=0.008) and E1/androstenedione (A4) (p=0.010) in the BMI>25 kg/m² group, when compared to that in the BMI<25 kg/m² group. The values of E2/T and E1/A4 were used to evaluate the cytochrome P450 aromatase enzyme activity in the steroidogenic pathway. Both aromatase activities negatively correlated with the maternal BMI and positively correlated with the Matsuda index in women with GDM.

CONCLUSIONS

NGT women and GDM women with normal weight presented with different steroid hormone profiles. Steroidogenic pathway profiling of sex hormones synthesis showed a significant increase in the production of DHEA, T, E1, and E2 in GDM women with normal weight. Additionally, the alteration of steroid hormone metabolism was related to maternal BMI in women with GDM, and GDM women with overweight showed reduced estrogen production and decreased insulin sensitivity compared with GDM women with normal weight.

Steroids, steroid associated substances and gestational diabetes mellitus

As gestational diabetes mellitus (GDM) is both a frequent and serious complication, steroid levels in pregnancy are extremely elevated and their role in pregnancy is crucial, this review focuses on the role of steroids and related substances in the GDM pathophysiology. Low SHBG levels are associated with insulin resistance and hyperinsulinemia, while also predicting a predisposition to GDM. Other relevant agents are placental hormones such as kisspeptin and CRH, playing also an important role beyond pregnancy, but which are synthesized here in smaller amounts in the hypothalamus. These hormones affect both the course of pregnancy as well as the synthesis of pregnancy steroids and may also be involved in the GDM pathophysiology. Steroids, whose biosynthesis is mainly provided by the fetal adrenal glands, placenta, maternal adrenal glands, and both maternal and fetal livers, are also synthesized in limited amounts directly in the pancreas and may influence the development of GDM. These substances involve the sulfated Δ5 steroids primarily acting via modulating different ion channels and influencing the development of GDM in different directions, mostly diabetogenic progesterone and predominantly anti-diabetic estradiol acting both in genomic and non-genomic way, androgens associated with IR and hyperinsulinemia, neuroactive steroids affecting the pituitary functioning, and cortisol whose production is stimulated by CRH but which suppresses its pro-inflammatory effects. Due to the complex actions of steroids, studies assessing their predominant effect and studies assessing their predictive values for estimating predisposition to GDM are needed.

Late gestational testosterone exposure causes glucose deregulation and elevated cardiac VCAM-1 and DPP-4 activity in rats

CONTEXT

Increased vascular cell adhesion molecule-1 (VCAM-1) has been reported to be a critical link between obesity and atherosclerotic cardiovascular diseases while dipeptidyl peptidase-4 (DPP-4) has been implicated in the development of disrupted glucose regulation and inflammation.

OBJECTIVE

This study aimed to investigate the effect of gestational testosterone exposure on glucose metabolism, atherogenic dyslipidemia, as well as circulating and cardiac VCAM-1, oxidative stress biomarkers and DPP-4 activity in pregnant rats.

METHODS

Pregnant Wistar rats received either vehicle or testosterone (0.5 mg/kg; sc) between gestational days 14 and 19.

RESULTS

Gestational testosterone exposure caused impaired glucose homeostasis that was accompanied with atherogenic dyslipidemia, elevated circulating and cardiac levels of VCAM-1, uric acid, malondialdehyde as well as increased DPP-4 activity. However, nitric oxide levels were decreased.

CONCLUSION

This study shows that gestational testosterone exposure causes glucose deregulation and atherogenic dyslipidemia that is accompanied by increased circulating and cardiac VCAM-1 and DPP-4 activity.

Maternal phthalate and phthalate alternative metabolites and urinary biomarkers of estrogens and testosterones across pregnancy

BACKGROUND/OBJECTIVES

Pregnant women are ubiquitously exposed to phthalates from food packaging materials and personal care products. Phthalates alter estrogen and testosterone concentrations in experimental models, but their ability to impact these hormones in human pregnancy is not well characterized.

METHODS

We recruited women ages 18-40 into the Illinois Kids Development Study (I-KIDS) in early pregnancy. Participants provided up to 5 first-morning urine samples across pregnancy (8-40 weeks gestation) that we pooled for quantification of 19 phthalate or phthalate alternative metabolites. Either individual (ng/mL) or molar sums (nmol/mL) of metabolites were used as exposure biomarkers. We summed urinary concentrations (ng/mL) of eight major estrogen (SumEstrogens) and two major testosterone (SumTestosterones) metabolites measured at median 13, 28, and 34 weeks gestation. We also estimated the ratio of estrogens-to-androgens. Linear mixed-effects models assessed relationships of phthalates/alternatives as continuous measures or as concentration quartiles with SumEstrogens, SumTestosterones, and the Estrogen/Androgen ratio in 434 women. In our models, we controlled for age, race, education, parity, smoking in the first trimester, pre-pregnancy body mass index, diet quality, conception season, fetal sex, and gestational age at hormone assessment. We also explored whether gestational age at hormone assessment or fetal sex modified these associations. All biomarkers and outcomes were specific gravity-adjusted, and continuous exposures and outcomes were also natural log-transformed.

RESULTS

Most participants were non-Hispanic white (80.9%), college educated (82.2%), and had urinary phthalate/alternative metabolite concentrations similar to those of reproductive-aged U.S. women. Overall, select phthalate metabolites were positively associated with SumEstrogens and SumTestosterones, but negatively associated with the Estrogen/Androgen ratio. For example, SumEstrogens was 5.1% (95%CI: 1.8, 8.5) higher with every 2-fold increase in sum of di(2-ethylhexyl) phthalate metabolites, while SumTestosterones was 7.9% (95%CI: 1.0, 15.3) higher and Estrogen/Androgen ratio was -7.7% (95%CI: -13.6, -1.4) lower with every 2-fold increase in monoethyl phthalate. However, phthalate alternatives were only positively associated with SumEstrogens, which was 2.4% (95%CI: 0.4, 4.5) and 3.2% (95%CI: 0.7, 5.8) higher with every 2-fold increase in sum of di(isononyl) cyclohexane-1,2-dicarboxylate metabolites and sum of di(2-ethylhexyl) terephthalate metabolites, respectively. Gestational age- and fetal sex-specific associations were only consistently observed for associations of phthalates/alternatives with SumEstrogens, where associations were strongest in mid-to-late pregnancy in women carrying females.

CONCLUSION

Phthalates/alternatives may impact gestational hormones, with potential for gestational age- and fetal sex-specific associations. Whether maternal urinary estrogens and testosterones mediate associations of phthalates/alternatives with pregnancy and fetal outcomes merits further investigation.

CTRP-1 levels are related to insulin resistance in pregnancy and gestational diabetes mellitus

Recent studies have shown higher levels of CTRP-1 (C1QTNF-related protein) in patients with type 2 diabetes compared to controls. We aimed at investigating CTRP-1 in gestational diabetes mellitus (GDM). CTRP-1 levels were investigated in 167 women (93 with normal glucose tolerance (NGT), 74 GDM) of a high-risk population for GDM. GDM was further divided into GDM subtypes depending on a predominant insulin sensitivity issue (GDM-IR) or secretion deficit (GDM-IS). Glucose tolerance was assessed with indices [Matsuda index, Stumvoll first phase index, insulin-secretion-sensitivity-index 2 (ISSI-2), area-under-the-curve (AUC) insulin, AUC glucose] derived from an oral glucose tolerance test (oGTT) performed at < 21 and 24–28 weeks of gestation. In pregnancy, CTRP-1 levels of GDM (76.86 ± 37.81 ng/ml) and NGT (82.2 ± 35.34 ng/ml; p = 0.104) were similar. However, GDM-IR women (65.18 ± 42.18 ng/ml) had significantly lower CTRP-1 levels compared to GDM-IS (85.10 ± 28.14 ng/ml; p = 0.009) and NGT (p = 0.006). CTRP-1 levels correlated negatively with weight, AUC insulin, Stumvoll first phase index, bioavailable estradiol and positively with HbA1c, Matsuda Index and ISSI-2. A multiple regression analysis revealed bioavailable estradiol (β = − 0.280, p = 0.008) and HbA1c (β = 0.238; p = 0.018) as the main variables associated with CTRP-1 in GDM. Postpartum, waist and hip measurements were predictive of CRTP-1 levels instead. CTRP-1 levels were higher postpartum than during pregnancy (91.92 ± 47.27 vs.82.44 ± 38.99 ng/ml; p = 0.013). CTRP-1 is related to insulin resistance in pregnancy and might be a metabolic biomarker for insulin resistance in GDM. CTRP-1 levels were significantly lower during pregnancy than postpartum, probably due to rising insulin resistance during pregnancy.

The impact of maternal asthma during pregnancy on fetal growth and development: a review

INTRODUCTION

Asthma is a highly prevalent co-morbidity during pregnancy that can worsen as gestation progresses and is associated with several adverse perinatal outcomes. These adverse outcomes often result from uncontrolled asthma during pregnancy and acute asthma exacerbations that are associated with alterations in placental function and fetal growth.

AREAS COVERED

This paper will discuss how maternal asthma in pregnancy affects fetal growth and development which may alter future offspring health. Changes in placental function occur in a sex-specific manner in pregnancies complicated by asthma and result in differences in fetal growth and development which may influence child health. The follow up of children from mothers with asthma suggests they are at greater risk of developing asthma, have alterations in microvascular structure that may contribute to a future risk of cardiovascular disease and epigenetic modifications in immune cell function. The current evidence suggests that appropriately managed asthma during pregnancy results in normal fetal growth and development.

EXPERT OPINION

Clinical management of asthma during pregnancy needs significant improvement to prevent adverse outcomes for the fetus. The key to improving maternal and fetal outcomes is through education of health professionals and parents about controlling asthma during pregnancy.

Developmental programming of insulin resistance: are androgens the culprits?

Insulin resistance is a common feature of many metabolic disorders. The dramatic rise in the incidence of insulin resistance over the past decade has enhanced focus on its developmental origins. Since various developmental insults ranging from maternal disease, stress, over/undernutrition, and exposure to environmental chemicals can all program the development of insulin resistance, common mechanisms may be involved. This review discusses the possibility that increases in maternal androgens associated with these various insults are key mediators in programming insulin resistance. Additionally, the intermediaries through which androgens misprogram tissue insulin sensitivity, such as changes in inflammatory, oxidative, and lipotoxic states, epigenetic, gut microbiome and insulin, as well as data gaps to be filled are also discussed.

Influence of Estrogens on Uterine Vascular Adaptation in Normal and Preeclamptic Pregnancies

During pregnancy, the maternal cardiovascular system undergoes significant changes, including increased heart rate, cardiac output, plasma volume, and uteroplacental blood flow (UPBF) that are required for a successful pregnancy outcome. The increased UPBF is secondary to profound circumferential growth that extends from the downstream small spiral arteries to the upstream conduit main uterine artery. Although some of the mechanisms underlying uterine vascular remodeling are, in part, known, the factors that drive the remodeling are less clear. That higher circulating levels of estrogens are positively correlated with gestational uterine vascular remodeling suggests their involvement in this process. Estrogens binding to the estrogen receptors expressed in cytotrophoblast cells and in the uterine artery wall stimulate an outward hypertrophic remodeling of uterine vasculature. In preeclampsia, generally lower concentrations of estrogens limit the proper uterine remodeling, thereby reducing UPBF increases and restricting the growth of the fetus. This review aims to report estrogenic regulation of the maternal uterine circulatory adaptation in physiological and pathological pregnancy that favors vasodilation, and to consider the underlying molecular mechanisms by which estrogens regulate uteroplacental hemodynamics.

Fetal adrenal gland size in gestational diabetes mellitus

Background The aim of this study was to compare the adrenal gland size of fetuses of women with gestational diabetes mellitus (GDM) with that of healthy control fetuses. Methods This prospective cross-sectional study included measurements of the adrenal gland size of 62 GDM fetuses (GDM group) and 370 normal controls (control group) between the 19th and 41st week of gestation. A standardized transversal plane was used to measure the total width and the medulla width. The cortex width and an adrenal gland ratio (total width/medulla width) were calculated from these data. Adrenal gland size measurements were adjusted to the week of gestation and compared between the two groups in a multivariable linear regression analysis. A variance decomposition metric was used to compare the relative importance of predictors of the different adrenal gland size measurements. Results For all the investigated parameters of the adrenal gland size, increased values were found in the case of GDM (P < 0.05), while adjusting for the week of gestation. GDM seems to have a greater impact on the size of the cortex than on the size of the medulla. Conclusion The fetal adrenal gland is enlarged in pregnancy complicated by GDM. The width of the cortex seems to be particularly affected.

ETA-mediated anti-TNF-α therapy ameliorates the phenotype of PCOS model induced by letrozole

Chronic inflammation is a typical characteristic of polycystic ovary syndrome (PCOS), in which, tumor necrosis factor (TNF)-α plays an important role. We investigated whether anti-TNF-α therapy can alleviate the core phenotypes of PCOS. In pubertal female Wistar rats, release pellets of letrozole (LET) were administered continuously for 90 days to induce PCOS-like phenotypes, followed by treatment with etanercept (ETA), a TNF-α inhibitor. ETA significantly inhibited increases in body weight and androgen, TNF-α, and MCP-1 levels, excessive recruitment of lipid droplets, altered levels of pre-adipose differentiation markers, and abnormal development of follicles. In addition, TNF-α and testosterone (T) levels in the rat sera were significantly positively correlated. Further experiments were performed to investigate the relationship between TNF-α and androgen. Persistent exposure of the RAW 264.7 cell line to low doses of testosterone significantly enhanced TNF-α expression and activated the NF-κB signaling pathway, which were blocked by ETA. Furthermore, treatment with TNF-α promoted the production of testosterone in KGN granulosa cells by reducing CYP19A1 expression, whereas ETA treatment blocked this process. In conclusion, anti-TNF-α therapy with ETA may be an efficient method to alleviate PCOS, whose underlying mechanism may be associated with its ability to reduce excessive androgen levels.

Associations of Phthalates and Phthalate Replacements With CRH and Other Hormones Among Pregnant Women in Puerto Rico

CONTEXT

Phthalates are endocrine-disrupting chemicals that may be associated with adverse birth outcomes. Dysregulation of maternal endocrine homeostasis could be a possible biological pathway between phthalates and birth outcomes.

OBJECTIVE

Examine associations between 19 maternal urinary phthalate or phthalate replacement metabolites and 9 serum hormones measured over two time points during pregnancy.

DESIGN

Longitudinal study conducted in the PROTECT pregnancy cohort.

SETTING

Puerto Rico.

PATIENTS

Six hundred seventy-seven women in the first trimester of pregnancy.

MAIN OUTCOME MEASURES SERUM

CRH, estriol, SHBG, progesterone, TSH, total T3, free T4, total T4, and testosterone.

RESULTS

T3 was significantly associated with most metabolites. CRH was inversely associated with mono carboxyisononyl phthalate [MCNP; percent change (%Δ), -4.08; 95% CI, -7.24, -0.804], mono-3-carboxypropyl phthalate (MCPP; %Δ, -5.25; 95% CI, -8.26, -2.14), mono-2-ethyl-5-carboxypentyl phthalate (MECPP; %Δ, -18.4; 95% CI, -30.4, -4.37), mono-2-ethyl-5-hydroxyhexyl phthalate (MEHHP; %Δ, -13.4; 95% CI, -22.7, -2.92), and mono-2-ethyl-5-oxohexyl phthalate (MEOHP; %Δ, -12.7; 95% CI, -22.2, -2.20). Positive associations were found between numerous phthalate metabolites and free T4, T4, and the T3/T4 ratio. Testosterone was positively associated with mono hydroxybutyl phthalate (MHBP; %Δ, 4.71; 95% CI, 0.27, 9.35) and inversely associated with monoethyl phthalate (MEP; %Δ, -14.5; 95% CI, -24.3, -3.42), and relationships with MCNP and mono carboxyisooctyl phthalate (MCOP) were significantly modified by study visit. Finally, an inverse association was found between mono-2-ethyl-5-hydrohexyl terephthalate (MEHHTP), a terephthalate metabolite, and progesterone at visit 3 only (%Δ, -13.1; 95% CI, -22.3, -2.75).

CONCLUSIONS

These results indicate that exposure to phthalates may differentially impact the maternal endocrine system at different points during pregnancy, and that exposures to phthalate replacement chemicals may be particularly important to consider in future human health studies.

Steroid hormones and pregnancy

Pregnancy is associated with physiological adjustments in order to allow adequate growth and fetal development. In particular, steroids are necessary to maintain in balance numerous functions during gestation. Steroidogenesis in the maternal, placental and fetal compartments and the biological effects of progestins and estrogens that play a pivotal role before and during pregnancy are described. Although it is well-known that androgens are considered as substrate for estrogens biosynthesis, their biosynthesis and functionality in placental and other tissues have been questioned. As compared with healthy pregnancy, steroid hormones levels have been found altered in complicated pregnancies and hormonal treatments have been used is some pathologies. Therefore, the aim of this work was to review the biosynthesis, function and regulation of progestins, androgens and estrogens during gestation. Furthermore, steroid hormones concentrations during healthy and complicated pregnancy as well hormonal therapies for the prevention of miscarriages and preterm deliveries are discussed in the present review.

Altered umbilical sex steroids in preterm infants born small for gestational age

Background: Boys born small for gestational age (SGA) are at increased risk of testicular dysgenesis syndrome, and girls born SGA face the risk of polycystic ovary syndrome later in life. Our aim was to study whether neonates born SGA have an altered profile of steroid hormones at birth.Materials and methods: A total of 168 singletons (99 boys, 69 girls) born at 32.0-36.9 gestational weeks were recruited to a population-based, university hospital, single-center study. Of these, 31 infants (17 boys, 14 girls) were born SGA. The concentrations of dehydroepiandrosterone sulfate (DHEAS), androstenedione, testosterone, dihydrotestosterone, estrone, estradiol, cortisone, and cortisol were analyzed in umbilical cord serum with mass spectrometry.Results: Girls born SGA had higher levels of androstenedione than girls born appropriate for gestational age (AGA) (4.0 versus 2.6 nmol/L, p = .002). Boys born SGA had lower levels of estrone than boys born AGA (33 822 versus 62 471 pmol/L, p = .038). Infants born SGA had lower levels of cortisone than infants born AGA, both in girls (340 versus 579 nmol/L, p = .010) and in boys (308 versus 521 nmol/L, p = .045). Furthermore, boys born SGA had a higher cortisol/cortisone ratio than boys born AGA (0.41 versus 0.25, p = .028). Gestational age correlated with DHEAS (boys r = 0.48, p = .000, girls r = 0.35, p = .013), and cortisol (boys r = 0.48, p = .000, girls r = 0.29, p = .039).Conclusions: In moderate-to-late preterm infants born SGA, we observed a different steroid hormone profile in cord serum. Girls born SGA show increased levels of androstenedione and boys born SGA show decreased levels of estrone in cord serum, which could be related to placental aromatase deficiency in intrauterine growth restriction.

Maternal Diabetes Mellitus and Genital Anomalies in Male Offspring: A Nationwide Cohort Study in 2 Nordic Countries

BACKGROUND

Pre-existing diabetes has been associated with an increased risk of congenital malformations overall, but studies on genital anomalies in boys are conflicting and possible causal mechanisms are not well understood. Previous studies have mainly assessed pregestational and gestational diabetes in combination. Yet considering the vulnerable time windows for the genital anomalies, associations could well differ between types of diabetes and between the 2 genital anomalies and we therefore aimed to study this further.

METHODS

A population-based cohort study of 2,416,246 singleton live-born boys from Denmark (1978-2012) and Sweden (1987-2012) was carried out using Danish and Swedish register-based data. Using Cox regression models, we estimated hazard ratios for hypospadias and cryptorchidism according to maternal diabetes. We considered type and severity of diabetes, as well as timing of diagnosis in relation to birth.

RESULTS

Pregestational type 1 diabetes was associated with a higher risk of both genital anomalies. The highest risks were seen for boys of mothers with diabetic complications (hazard ratio for hypospadias = 2.33 [95% confidence interval, 1.48, 3.66] and hazard ratio for cryptorchidism = 1.92 [95% confidence interval, 1.39, 2.65]). Gestational diabetes was associated with slightly increased risks of both genital anomalies.

CONCLUSIONS

These results are consistent with the hypothesis that poor glycemic control may interfere with fetal genital development in the critical early period of organogenesis. Given the widespread and increasing occurrence of diabetes, these results are of public health importance.

Congenital Abnormalities of the Male Reproductive System and Risk of Autism Spectrum Disorders

Androgens have an extensive influence on brain development in regions of the brain that are relevant for autism spectrum disorder (ASD), yet their etiological involvement remains unclear. Hypospadias (abnormal positioning of the urethral opening) and cryptorchidism (undescended testes) are 2 relatively common male birth defects that are strongly associated with prenatal androgen deficiencies. Having either disorder is a proxy indicator of atypical gestational androgen exposure, yet the association between these disorders and autism has not been extensively studied. We analyzed male singleton live births (n = 224,598) occurring from January 1, 1999, through December 31, 2013, in a large Israeli health-care organization. Boys with autism, cryptorchidism, and hypospadias were identified via International Classification of Diseases, Ninth Revision, codes, with further verification of autism case status by review of medical records. In multivariable-adjusted analyses, the odds ratio for ASD among boys with either condition was 1.62 (95% confidence interval (CI): 1.44, 1.82). The odds ratio for boys with cryptorchidism only was 1.55 (95% CI: 1.34, 1.78), and that for boys with hypospadias only was 1.65 (95% CI: 1.38, 1.98). ASD risk was not elevated among unaffected brothers of hypospadias or cryptorchidism cases, despite familial aggregation of all 3 conditions, providing some indication for the possibility of pregnancy-specific risk factors driving the observed associations. Results suggest that in-utero hypoandrogenicity could play a role in ASD etiology.

Fetal Sex, Need for Insulin, and Perinatal Outcomes in Gestational Diabetes Mellitus: An Observational Cohort Study

PURPOSE

This was a prospective observational cohort study that aimed to determine whether fetal sex influences the maternal and fetal outcomes of gestational diabetes mellitus (GDM).

METHODS

In this study, 327 European primiparous women were consecutively recruited after diagnosis of GDM. AUC on the oral glucose tolerance test (OGTT), need for insulin therapy, maternal and obstetrical outcomes, and fetal fat mass (by measuring the thickness of the anterior abdominal subcutaneous tissue) were recorded and compared between the two subgroups of female and male fetuses.

FINDINGS

Despite the absence of differences in multiple comparisons of the OGTT, the AUC-OGTT was significantly higher in women carrying a male fetus (22.6 [3.2] mmol/L vs 19.7 [2.8] mmol/L). The abdominal fat thickness appeared to increase with gestational age, with higher growth in male fetuses than in female fetuses. The overall risk of need for insulin therapy was significantly higher in women carrying a male fetus (odds ratio = 1.837). At delivery, birthweight was higher in males than in females only if adjusted for gestational age, similarly for placental weight, otherwise there were no significant differences between the groups in total length of gestation, rates of cesarean delivery, and Apgar scores.

IMPLICATIONS

Overall, our data propose an association between fetal sex and GDM outcomes, suggesting the hypothesis that in maternal-fetal interactions, the fetus can affect maternal glucose metabolism.

Dihydrotestosterone levels at birth associate positively with higher proportions of circulating immature/naïve CD5+ B cells in boys

Boys present with higher proportions of immature/naïve CD5⁺ B cells than girls up to 3 years of age. Boys also have higher fractions of regulatory T cells (Tregs) in early infancy, but the mechanisms for these sex-related differences are unknown. In the prospective FARMFLORA follow-up study of 23 boys and 25 girls, we investigated if these immunological differences remained at 8 years of age. We also examined if testosterone or dihydrotestosterone (DHT) levels at birth and at 8 years of age were associated with immune maturation. Immunological variables and androgen levels were examined and measured in blood samples obtained at birth, 3–5 days and at 8 years of age. Boys had higher proportions of CD5⁺ and immature/transitional CD24^hiCD38^hi B cells, whereas girls had higher fractions of B cells with a memory phenotype at 8 years of age. School-aged boys also presented with higher frequencies of Tregs, and a greater capacity to produce T-cell-associated cytokines. Among boys, higher cord blood DHT levels were associated with higher proportions of CD5⁺ B cells in early infancy and at 8 years of life. These results suggest that DHT actions in utero might be involved in the mechanism for delayed peripheral B-cell maturation in boys.

Maternal Polycystic Ovary Syndrome and Risk for Attention-Deficit/Hyperactivity Disorder in the Offspring

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is the most common childhood neurodevelopmental disorder, and boys are two to three times more likely to develop ADHD. Maternal polycystic ovary syndrome (PCOS), a common metabolic disorder associated with excess circulating androgens, has been associated with increased risk for autism spectrum disorder in the offspring. In this study, we aimed to investigate whether maternal PCOS increases the risk for ADHD in the offspring.

METHODS

We conducted a matched case-control study using health and population data registers for all children born in Sweden from 1984 to 2008. Maternal PCOS was defined by ICD-coded register diagnosis. The outcome of ADHD was defined as an ICD-coded register diagnosis of ADHD and/or registered prescription of medications to treat ADHD. A total of 58,912 ADHD cases (68.8% male) were identified and matched to 499,998 unaffected controls by sex and birth month and year.

RESULTS

Maternal PCOS increased the odds of offspring ADHD by 42% after adjustment for confounders (odds ratio [OR], 1.42; 95% confidence interval [CI], 1.26-1.58). Exclusion of ADHD cases with comorbid autism spectrum disorder attenuated but did not explain the relationship (OR, 1.34; 95% CI, 1.18-1.52). The risk was somewhat elevated for ADHD with comorbid autism spectrum disorder (OR, 1.76; 95% CI, 1.37-2.26). The risk for ADHD was higher among obese mothers with PCOS (OR, 1.68; 95% CI, 1.31-2.17) and was highest among obese mothers with PCOS and other features of metabolic syndrome (OR, 2.59; 95% CI, 1.02-6.58).

CONCLUSIONS

This study provides evidence that maternal PCOS may subtly influence the neurodevelopment of the offspring, resulting in increased risk for neurodevelopmental disorders such as ADHD.

Obesity during pregnancy affects sex steroid concentrations depending on fetal gender

BACKGROUND/OBJECTIVE

It is not clear whether maternal obesity along with fetal gender affect sex steroid metabolism during pregnancy. Therefore, we compared sex steroid concentrations and placental expression of steroidogenic enzymes between non-obese and obese pregnant women with non-pathological pregnancies, and investigated the influence of fetal gender on these parameters.

METHODS

In 35 normal weight (body mass index (BMI) 20-24.9 kg m^-2) (controls) and 36 obese women (BMI 30-36 kg m^-2) (obese), a fasting blood sample was obtained at first and at third trimester of gestation to measure progesterone, dehydroepiandrosterone (DHEA), DHEA sulfate, androstenedione, testosterone and estradiol by liquid chromatography-tandem mass spectrometry and estrone by radioimmunoassay. In a subset of women, placental mRNA and protein expression of steroidogenic enzymes was measured by quantitative PCR and western blot, respectively. The comparisons were primarily made between controls and obese, and then separately according to fetal gender.

RESULTS

At first and third trimesters of gestation serum progesterone was lower whereas testosterone was higher in obese women (P<0.05, respectively). Upon analyzing according to fetal gender, lower progesterone levels were present in obese pregnant women with male fetuses at first trimester and with female fetuses at third trimester (P<0.05, respectively). Testosterone was higher in obese women with male fetuses compared to control women with male fetuses (P<0.05). The placental protein expression of P450scc was higher in obese women compared to controls (P<0.05). P450 aromatase was higher in obese women with female fetuses (P=0.009), whereas in obese women with male fetuses P450 aromatase was lower compared to control women (P=0.026).

CONCLUSIONS

Obesity in non-pathological pregnancies alters the maternal serum progesterone and testosterone concentrations depending on fetal gender. These changes can be attributed to gender-related placental adaptations, as the expression of P450 aromatase is different in placentas from females compared to males.

Umbilical cord blood androgen levels in girls and boys assessed by gas chromatography-tandem mass spectrometry

Androgen exposure of the fetus during gestation plays an important role in human physiology and pathophysiology, but assessment of androgens, in particular dihydrotestosterone (DHT), in human umbilical cord blood is technically challenging. The aim of this study was to assess umbilical cord androgen levels, including DHT, at birth by a highly sensitive assay, and study their association with sex of the infant, sex-hormone-binding globulin (SHBG) levels, and gestational age at delivery. Swedish infants (27 girls, 26 boys) were recruited at maternity care clinics in Southern Sweden. Umbilical cord blood levels of dehydroepiandrosterone (DHEA), androstenedione, testosterone and DHT at delivery were assessed by a gas chromatography-tandem mass spectrometry assay. Cord blood levels of DHT were 2.4-fold higher in boys (median 27.8pg/mL) than in girls (11.5pg/mL), while the sex difference was less pronounced for testosterone (1.3-fold higher in boys) and non-significant for DHEA and androstenedione. Gestational age at delivery associated inversely with DHT levels in boys and with DHEA levels in girls. There was a strong inverse correlation between SHBG and DHEA in both sexes, while there were no associations between SHBG and testosterone or DHT levels. In conclusion, using state of the art technology, we report that there is a pronounced sexual dimorphism in human umbilical cord blood DHT levels. The possibility to assess a complete androgen profile in human cord blood opens up for future increased understanding of the biological impact of the fetal androgen milieu.

Placental control of drug delivery

The placenta serves as the interface between the maternal and fetal circulations and regulates the transfer of oxygen, nutrients, and waste products. When exogenous substances are present in the maternal bloodstream-whether from environmental contact, occupational exposure, medication, or drug abuse-the extent to which this exposure affects the fetus is determined by transport and biotransformation processes in the placental barrier. Advances in drug delivery strategies are expected to improve the treatment of maternal and fetal diseases encountered during pregnancy.

From Pregnancy to Preeclampsia: A Key Role for Estrogens

Preeclampsia (PE) results in placental dysfunction and is one of the primary causes of maternal and fetal mortality and morbidity. During pregnancy, estrogen is produced primarily in the placenta by conversion of androgen precursors originating from maternal and fetal adrenal glands. These processes lead to increased plasma estrogen concentrations compared with levels in nonpregnant women. Aberrant production of estrogens could play a key role in PE symptoms because they are exclusively produced by the placenta and they promote angiogenesis and vasodilation. Previous assessments of estrogen synthesis during PE yielded conflicting results, possibly because of the lack of specificity of the assays. However, with the introduction of reliable analytical protocols using liquid chromatography/mass spectrometry or gas chromatography/mass spectrometry, more recent studies suggest a marked decrease in estradiol levels in PE. The aim of this review is to summarize current knowledge of estrogen synthesis, regulation in the placenta, and biological effects during pregnancy and PE. Moreover, this review highlights the links among the occurrence of PE, estrogen biosynthesis, angiogenic factors, and cardiovascular risk factors. A close link between estrogen dysregulation and PE occurrence might validate estrogen levels as a biomarker but could also reveal a potential approach for prevention or cure of PE.

Fetal gender is not associated with either gestational diabetes mellitus or placental weight: A cohort study

AIM

This study assessed whether male fetal gender increases the risk of maternal gestational diabetes mellitus (GDM) and investigated the association with placental weight.

METHODS

The study included 20,149 women without pregestational diabetes who delivered singletons at our hospital between January 2002 and December 2010. There was universal screening for GDM, and all placentas were weighed at delivery.

RESULTS

GDM (affecting 14.2% of women) was not associated with fetal gender (male fetuses in women without and with GDM: 51.8% vs. 51.7%, respectively; P=0.957), and remained likewise after logistic-regression analysis of risk factors for GDM (OR: 1.007, 95% CI: 0.930-1.091; P=0.858). Placental weights were 600±126g, 596±123g, 584±118g and 587±181g in women with GDM/female, GDM/male, no GDM/female and no GDM/male fetuses, respectively (GDM effect: P=0.017; gender effect: P=0.41; GDM * gender effect: P=0.16).

CONCLUSION

The present results suggest that fetal gender is not associated with GDM and, while placental weights were higher in cases of GDM, there were still no gender effects.

Elevated Testosterone Reduces Uterine Blood Flow, Spiral Artery Elongation, and Placental Oxygenation in Pregnant Rats

Elevated maternal testosterone levels are shown to cause fetal growth restriction, eventually culminating in sex-specific adult-onset hypertension that is more pronounced in males than in females. In this study, we tested whether uteroplacental and fetoplacental disturbances underlie fetal growth restriction and if these changes vary in male and female placentas. Pregnant Sprague-Dawley rats were injected with vehicle (n=16) or testosterone propionate (0.5 mg/kg per day from gestation day 15-19; n=16). On gestation day 20, we quantified uterine artery blood flow using microultrasound, visualized placental arterial network using x-ray microcomputed tomography, determined fetoplacental hypoxia using pimonidazole and hypoxia-inducible factor-1α, and used Affymetrix array to determine changes in placental expression of genes involved in vascular development. Plasma testosterone levels increased 2-fold in testosterone-injected rats. Placental and fetal weights were lower in rats with elevated testosterone. Uterine artery blood flow was lower, and resistance index was higher in the testosterone group. Radial and spiral artery diameter and length, the number of fetoplacental arterial branches, and umbilical artery diameter were reduced in the testosterone group. In addition, markers of hypoxia in the placentas and fetuses were elevated in the testosterone group. The magnitude of changes in placental vasculature and hypoxia was greater in males than in females and was associated with sex-specific alteration of unique sets of genes involved in angiogenesis and blood vessel morphogenesis. The results demonstrate that elevated testosterone during gestation induces a decrease in uterine arterial blood flow and fetal sex-related uteroplacental vascular changes, which may set the stage for subsequent sex differences in adult-onset diseases.

Atypically rightward cerebral asymmetry in male adults with autism stratifies individuals with and without language delay

In humans, both language and fine motor skills are associated with left‐hemisphere specialization, whereas visuospatial skills are associated with right‐hemisphere specialization. Individuals with autism spectrum conditions (ASC) show a profile of deficits and strengths that involves these lateralized cognitive functions. Here we test the hypothesis that regions implicated in these functions are atypically rightward lateralized in individuals with ASC and, that such atypicality is associated with functional performance. Participants included 67 male, right‐handed adults with ASC and 69 age‐ and IQ‐matched neurotypical males. We assessed group differences in structural asymmetries in cortical regions of interest with voxel‐based analysis of grey matter volumes, followed by correlational analyses with measures of language, motor and visuospatial skills. We found stronger rightward lateralization within the inferior parietal lobule and reduced leftward lateralization extending along the auditory cortex comprising the planum temporale, Heschl's gyrus, posterior supramarginal gyrus, and parietal operculum, which was more pronounced in ASC individuals with delayed language onset compared to those without. Planned correlational analyses showed that for individuals with ASC, reduced leftward asymmetry in the auditory region was associated with more childhood social reciprocity difficulties. We conclude that atypical cerebral structural asymmetry is a potential candidate neurophenotype of ASC. Hum Brain Mapp 37:230–253, 2016. © 2015 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

Perinatal androgen exposure and adipose tissue programming: is there an impact on body weight fate?

Obesity is a major concern in public health because it is one of the main risk factors for the development of non-transmissible chronic diseases. The fact that there is a clear sex dimorphism in normal body fat distribution points out the role of sex steroids as key factors in the regulation and function of the adipose cell. Androgens affect adipogenesis and fat metabolism in the adipose tissue of males and females. Hormonal disorders during pregnancy may affect the fetal tissues, with long-term implications leading to the development of pathologies during adult life. Obesity and metabolic disease are among these. In this regard, animal models have demonstrated an abnormal fat distribution and modifications in the size and function of adipose cells in the female and male offspring of mothers exposed to androgen excess during pregnancy.

Bone development and mineral homeostasis in the fetus and neonate: roles of the calciotropic and phosphotropic hormones

Mineral and bone metabolism are regulated differently in utero compared with the adult. The fetal kidneys, intestines, and skeleton are not dominant sources of mineral supply for the fetus. Instead, the placenta meets the fetal need for mineral by actively transporting calcium, phosphorus, and magnesium from the maternal circulation. These minerals are maintained in the fetal circulation at higher concentrations than in the mother and normal adult, and such high levels appear necessary for the developing skeleton to accrete a normal amount of mineral by term. Parathyroid hormone (PTH) and calcitriol circulate at low concentrations in the fetal circulation. Fetal bone development and the regulation of serum minerals are critically dependent on PTH and PTH-related protein, but not vitamin D/calcitriol, fibroblast growth factor-23, calcitonin, or the sex steroids. After birth, the serum calcium falls and phosphorus rises before gradually reaching adult values over the subsequent 24-48 h. The intestines are the main source of mineral for the neonate, while the kidneys reabsorb mineral, and bone turnover contributes mineral to the circulation. This switch in the regulation of mineral homeostasis is triggered by loss of the placenta and a postnatal fall in serum calcium, and is followed in sequence by a rise in PTH and then an increase in calcitriol. Intestinal calcium absorption is initially a passive process facilitated by lactose, but later becomes active and calcitriol-dependent. However, calcitriol's role can be bypassed by increasing the calcium content of the diet, or by parenteral administration of calcium.

Elevated testosterone levels during rat pregnancy cause hypersensitivity to angiotensin II and attenuation of endothelium-dependent vasodilation in uterine arteries

Elevated testosterone levels increase maternal blood pressure and decrease uterine blood flow in pregnancy, resulting in abnormal perinatal outcomes. We tested whether elevated testosterone alters uterine artery adaptations during pregnancy, and whether these alterations depend on endothelium-derived factors such as nitric oxide, endothelium-derived hyperpolarizing factor, and prostacyclin, or endothelium-independent mechanisms such as angiotensin II (Ang-II). Pregnant Sprague-Dawley rats were injected with vehicle (n=20) or testosterone propionate (0.5 mg/kg per day from gestation day 15 to 19; n=20). Plasma testosterone levels increased 2-fold in testosterone-injected rats compared with controls. Elevated testosterone significantly decreased placental and pup weights compared with controls. In endothelium-intact uterine arteries, contractile responses to thromboxane, phenylephrine, and Ang-II were greater in testosterone-treated rats compared with controls. In endothelium-denuded arteries, contractile responses to Ang-II (pD2=9.1±0.04 versus 8.7±0.04 in controls; P<0.05), but not thromboxane and phenylephrine, were greater in testosterone-treated rats. Ang-II type 1b receptor expression was increased, whereas Ang-II type 2 receptor was decreased in testosterone-exposed arteries. In endothelium-denuded arteries, relaxations to sodium nitroprusside were unaffected. Endothelium-dependent relaxation to acetylcholine was significantly lower in arteries from testosterone-treated dams (Emax=51.80±6.9% versus 91.98±1.4% in controls; P<0.05). The assessment of endothelial factors showed that nitric oxide-, endothelium-derived hyperpolarizing factor-, and prostacyclin-mediated relaxations were blunted in testosterone-treated dams. Endothelial nitric oxide synthase, small conductance calcium-activated potassium channel-3, and prostacyclin receptor expressions were significantly decreased in arteries from testosterone-treated dams. Hypoxia-inducible factor-1α, Ankrd37, and Egln were significantly increased in testosterone-exposed placentas. These results suggest that elevated maternal testosterone impairs uterine vascular function, which may lead to an increased vascular resistance and a decrease in uterine blood flow.

Androgens in pregnancy: roles in parturition

BACKGROUND

Understanding the physiology of pregnancy enables effective management of pregnancy complications that could otherwise be life threatening for both mother and fetus. A functional uterus (i) retains the fetus in utero during pregnancy without initiating stretch-induced contractions and (ii) is able to dilate the cervix and contract the myometrium at term to deliver the fetus. The onset of labour is associated with successful cervical remodelling and contraction of myometrium, arising from concomitant activation of uterine immune and endocrine systems. A large body of evidence suggests that actions of local steroid hormones may drive changes occurring in the uterine microenvironment at term. Although there have been a number of studies considering the potential role(s) played by progesterone and estrogen at the time of parturition, the bio-availability and effects of androgens during pregnancy have received less scrutiny. The aim of this review is to highlight potential roles of androgens in the biology of pregnancy and parturition.

METHODS

A review of published literature was performed to address (i) androgen concentrations, including biosynthesis and clearance, in maternal and fetal compartments throughout gestation, (ii) associations of androgen concentrations with adverse pregnancy outcomes, (iii) the role of androgens in the physiology of cervical remodelling and finally (iv) the role of androgens in the physiology of myometrial function including any impact on contractility.

RESULTS

Some, but not all, androgens increase throughout gestation in maternal circulation. The effects of this increase are not fully understood; however, evidence suggests that increased androgens might regulate key processes during pregnancy and parturition. For example, androgens are believed to be critical for cervical remodelling at term, in particular cervical ripening, via regulation of cervical collagen fibril organization. Additionally, a number of studies highlight potential roles for androgens in myometrial relaxation via non-genomic, AR-independent pathways critical for the pregnancy reaching term. Understanding of the molecular events leading to myometrial relaxation is an important step towards development of novel targeted tocolytic drugs.

CONCLUSIONS

The increase in androgen levels throughout gestation is likely to be important for establishment and maintenance of pregnancy and initiation of parturition. Further investigation of the underlying mechanisms of androgen action on cervical remodelling and myometrial contractility is needed. The insights gained may facilitate the development of new therapeutic approaches to manage pregnancy complications such as preterm birth.

Maternal testosterone levels are associated with C-peptide levels in the Mexican American subset of the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study cohort

Altered sex hormone levels are thought to play an important role in adult-onset diseases including obesity, cardiovascular disease, and diabetes. They contribute to these complex diseases through changes in their availability, which is influenced, in part, by binding proteins. Insulin resistance, which is characteristic of these diseases, along with increased insulin secretion, is a physiologic change that occurs normally during pregnancy. To determine the relationship between insulin resistance and sex hormone levels, we examined the associations of sex hormone-binding globulin (SHBG) and testosterone with measures of glycemia and insulinemia in a healthy pregnant population. We measured fasting serum SHBG and testosterone levels in 215 Hispanic mothers of Mexican ancestry from the HAPO Study cohort and tested for associations between SHBG and testosterone levels and maternal plasma glucose and C-peptide. After adjusting for confounding variables, serum total testosterone (TT) was positively associated with fasting C-peptide (0.18 μg/l higher for TT higher by 1 SD, p=0.001) and 1-h C-peptide (0.79 μg/l higher for TT higher by 1 SD, p<0.001). Free testosterone (FT) was also positively associated with fasting C-peptide (0.19 μg/l higher for FT higher by 1 SD, p<0.001), and 1-h C-peptide (0.83 μg/l higher for FT higher by 1 SD, p<0.001). Although these findings are from a single cohort, this study provides evidence for an association between testosterone and C-peptide during pregnancy in a nondiabetic Hispanic obstetric population.