Evidence of high circulating testosterone in women with prior preeclampsia

Androgens in maternal vascular and placental function: implications for preeclampsia pathogenesis

Adequate maternal vascular adaptations and blood supply to the uterus and placenta are crucial for optimal oxygen and nutrient transport to growing fetuses of eutherian mammals, including humans. Multiple factors contribute to hemodynamics and structuring of placental vasculature essential for term pregnancy with minimal complications. In women, failure to achieve or sustain favorable pregnancy progression is, not surprisingly, associated with high incidence of antenatal complications, including preeclampsia, a hypertensive disorder of pregnancy. While the pathogenesis of preeclampsia in women remains unknown, a role for androgens is emerging. The relationship between androgens and maternal cardiovascular and placental function deserves particular consideration because testosterone levels in the circulation of preeclamptic women are elevated approximately two- to three-fold and are positively correlated with vascular dysfunction. Preeclampsia is also associated with elevated placental androgen receptor (AR) gene expression. Studies in animal models mimicking the pattern and level of increase of adult female testosterone levels to those found in preeclamptic pregnancies, replicate key features of preeclampsia, including gestational hypertension, endothelial dysfunction, exaggerated vasoconstriction to angiotensin II, reduced spiral artery remodeling, placental hypoxia, decreased nutrient transport and fetal growth restriction. Taken together, these data strongly implicate AR-mediated testosterone action as an important pathway contributing to clinical manifestation of preeclampsia. This review critically addresses this hypothesis, taking into consideration both clinical and preclinical data.

Sexual dimorphism in activation of placental autophagy in obese women with evidence for fetal programming from a placenta-specific mouse model

The incidence of maternal obesity and its co-morbidities (diabetes, cardiovascular disease) continues to increase at an alarming rate, with major public health implications. In utero exposure to maternal obesity has been associated with development of cardiovascular and metabolic diseases in the offspring as a result of developmental programming. The placenta regulates maternal-fetal metabolism and shows significant changes in its function with maternal obesity. Autophagy is a cell-survival process, which is responsible for the degradation of damaged organelles and misfolded proteins. Here we show an activation of autophagosomal formation and autophagosome-lysosome fusion in placentas of males but not females from overweight (OW) and obese (OB) women vs. normal weight (NW) women. However, total autophagic activity in these placentas appeared to be decreased as it showed an increase in SQSTM1/p62 and a decrease in lysosomal biogenesis. A mouse model with a targeted deletion of the essential autophagy gene Atg7 in placental tissue showed significant placental abnormalities comparable to those seen in human placenta with maternal obesity. These included a decrease in expression of mitochondrial genes and antioxidants, and decreased lysosomal biogenesis. Strikingly, the knockout mice were developmentally programmed as they showed an increased sensitivity to high-fat diet-induced obesity, hyperglycemia, hyperinsulinemia, increased adiposity, and cardiac remodeling. In summary, our results indicate a sexual dimorphism in placental autophagy in response to maternal obesity. We also show that autophagy plays an important role in placental function and that inhibition of placental autophagy programs the offspring to obesity, and to metabolic and cardiovascular diseases.

Dihydrotestosterone: Biochemistry, Physiology, and Clinical Implications of Elevated Blood Levels

Benefits associated with lowered serum DHT levels after 5α-reductase inhibitor (5AR-I) therapy in men have contributed to a misconception that circulating DHT levels are an important stimulus for androgenic action in target tissues (e.g., prostate). Yet evidence from clinical studies indicates that intracellular concentrations of androgens (particularly in androgen-sensitive tissues) are essentially independent of circulating levels. To assess the clinical significance of modest elevations in serum DHT and the DHT/testosterone (T) ratio observed in response to common T replacement therapy, a comprehensive review of the published literature was performed to identify relevant data. Although the primary focus of this review is about DHT in men, we also provide a brief overview of DHT in women. The available published data are limited by the lack of large, well-controlled studies of long duration that are sufficiently powered to expose subtle safety signals. Nonetheless, the preponderance of available clinical data indicates that modest elevations in circulating levels of DHT in response to androgen therapy should not be of concern in clinical practice. Elevated DHT has not been associated with increased risk of prostate disease (e.g., cancer or benign hyperplasia) nor does it appear to have any systemic effects on cardiovascular disease safety parameters (including increased risk of polycythemia) beyond those commonly observed with available T preparations. Well-controlled, long-term studies of transdermal DHT preparations have failed to identify safety signals unique to markedly elevated circulating DHT concentrations or signals materially different from T.

Maternal Preeclampsia and Androgens in the Offspring around Puberty: A Follow-Up Study

Background

Children born after preeclampsia may have a dominant androgen profile in puberty compared with other children. Circulating androgen concentrations at 11–12 years of age were compared between offspring born after preeclampsia, and children whose mothers did not have preeclampsia.

Methods

A total of 611 mother-offspring pairs were followed up 11 (daughters) or 12 (sons) years after birth: 218 pairs in the preeclampsia group, and 383 pairs without preeclampsia. Circulating total testosterone, androstenedione, dehydroepiandrosterone sulfate (DHEAS), and insulin-like growth factor I (IGF-I) were measured in the children. In boys, testicular volume was also measured.

Results

Among girls born after preeclampsia, DHEAS concentrations were higher than in unexposed girls (p<0.001), however, girls born after preeclampsia with severe features had the lowest DHEAS levels. In contrast, testosterone concentrations were highest in girls born after preeclampsia with severe features, both compared to other girls in the preeclampsia group, and compared to unexposed girls (p<0.001). For boys, testosterone concentrations were higher in the preeclampsia group compared with unexposed boys (p<0.001), and boys born after preeclampsia with severe features had the lowest concentrations of DHEAS. Compared with unexposed boys, testicular volume (p = 0.015) and IGF-I (p = 0.004) were higher for boys in the preeclampsia group, except for boys in the clinically severe preeclampsia group.

Conclusions

In utero exposure to preeclampsia is associated with androgen hormonal patterns in early puberty that depend on clinical severity of preeclampsia and sex of the offspring. The hormonal differences may reflect different timing of pubertal development, and may have consequences for future health of the offspring.

Fetal sex-related dysregulation in testosterone production and their receptor expression in the human placenta with preeclampsia

OBJECTIVE

To determine the effects of fetal sex on aromatase and androgen receptor (AR) expression in the placenta of normal and preeclamptic pregnancies.

STUDY DESIGN

Placentae from preeclamptic (five female and six male fetuses) and healthy pregnancies (seven female and seven male fetuses) were examined by immunofluorescence, western blotting and quantitative reverse transcriptase PCR.

RESULT

Placental AR levels were significantly higher (P<0.05) in placentae of both male and female fetuses compared with their respective sexes in normal pregnancies. The placental aromatase levels varied depending on fetal sex. If the fetus was female, aromatase levels were substantially higher (P<0.05) in preeclamptic than in normal placentae. If the fetus was male, the aromatase levels were significantly lower (P<0.05) in preeclamptic than in normal placentae. Placental aromatase levels were significantly higher (P<0.05) in male- than in female-bearing normal placentae.

CONCLUSION

Dysregulation in androgen production and signaling in preeclamptic placentae may contribute to placental abnormalities, increasing the frequency of maternal-fetal complications associated with preeclampsia.

Prenatal testosterone-induced fetal growth restriction is associated with down-regulation of rat placental amino acid transport

BACKGROUND

Exposure of pregnant mothers to elevated concentrations of circulating testosterone levels is associated with fetal growth restriction and delivery of small-for-gestational-age babies. We examined whether maternal testosterone crosses the placenta to directly suppress fetal growth or if it modifies placental function to reduce the capacity for transport of nutrients to the fetus.

METHODS

Pregnant rats were exposed to testosterone propionate (TP; 0.5 mg/kg) by daily subcutaneous injection from gestational days (GD) 15-19. Maternal and fetal testosterone levels, placental nutrient transport activity and expression of transporters and birth weight of pups and their anogenital distances were determined.

RESULTS

This dose of TP doubled maternal testosterone levels but had no effect on fetal testosterone levels. Maternal daily weight gain was significantly lower only on GD 19 in TP treated dams compared to controls. Placental weight and birth weight of pups were significantly reduced, but the anogenital distance of pups were unaffected by TP treatment. Maternal plasma amino acids concentrations were altered following testosterone exposure, with decreases in glutamine, glycine, tyrosine, serine, proline, and hydroxyproline and increases in asparagine, isoleucine, leucine, lysine, histidine and arginine. In the TP dams, placental system A amino acid transport activity was significantly reduced while placental glucose transport capacity was unaffected. Decreased expression of mRNA and protein levels of slc38a2/Snat2, an amino acid transporter, suggests that reduced transporter proteins may be responsible for the decrease in amino acid transport activity.

CONCLUSIONS

Taken together, these data suggest that increased maternal testosterone concentrations do not cross the placenta to directly suppress fetal growth but affects amino acid nutrient delivery to the fetus by downregulating specific amino acid transporter activity.

Regional differences in the prevalence of pre-eclampsia in relation to the risk factors for coronary artery disease in women in Finland

AIMS

The aim of this study was to examine the prevalence of pre-eclampsia in Southern, Eastern, and Northern Finland, and the relationship between history of pre-eclampsia and maternal coronary artery disease (CAD) risk factors.

METHODS AND RESULTS

Women aged 25-64 years, who participated in a cross-sectional population survey and had been pregnant (n=3650), were studied. The proportion of women who had ever had pre-eclampsia was lower in Southern (7.9%) compared with Northern Finland (13.9%) (P=0.001), but did not differ from Eastern Finland (11.1%). In the logistic regression model, the age-adjusted prevalence of pre-eclampsia was 1.92-fold in Northern (95% CI: 1.46-2.53, P<0.001) and 1.47-fold in Eastern Finland (95% CI: 1.11-1.96, P=0.008) compared with Southern Finland. The odds ratios (ORs) were 1.70 (95% CI: 1.21-2.38, P=0.002) and 1.16 (95% CI: 0.82-1.64, P=0.40), respectively, when adjusted for age at first birth, current age, parity, body mass index (BMI), increased blood cholesterol, hypertension, diabetes/impaired glucose tolerance, CAD, and mother's myocardial infarction. History of pre-eclampsia was associated with increased blood cholesterol, higher current BMI and blood pressure, and higher current prevalence of hypertension, diabetes/impaired glucose tolerance.

CONCLUSIONS

Pre-eclampsia is most prevalent in the Northern part of Finland and could only be partly explained by higher prevalence of CAD risk factors.