Insulin sensitivity in male sheep born to ewes treated with testosterone during pregnancy

Sex-Specific Perturbation of Systemic Lipidomic Profile in Newborn Lambs Impacted by Prenatal Testosterone Excess

Gestational hyperandrogenism adversely impacts offspring health. Using an ovine model, we found that prenatal testosterone (T) excess adversely affects growth and cardiometabolic outcomes in female offspring and produces sex-specific effects on fetal myocardium. Since lipids are essential to cardiometabolic function, we hypothesized that prenatal T excess leads to sex-specific disruptions in lipid metabolism at birth. Shotgun lipidomics was performed on the plasma samples collected 48 hours after birth from female (F) and male (M) lambs of control (C) and (T) sheep (CF = 4, TF = 7, CM = 5, TM = 10) and data were analyzed by univariate analysis, multivariate dimensionality reduction modeling followed by functional enrichment, and pathway analyses. Biosynthesis of phosphatidylserine was the major pathway responsible for sex differences in controls. Unsupervised and supervised models showed separation between C and T in both sexes with glycerophospholipids and glycerolipids classes being responsible for the sex differences between C and T. T excess increased cholesterol in females while decreasing phosphatidylcholine levels in male lambs. Specifically, T excess: 1) suppressed the phosphatidylethanolamine N-methyltransferase (PEMT) phosphatidylcholine synthesis pathway overall and in TM lambs as opposed to suppression of carnitine levels overall and TF lambs; and 2) activated biosynthesis of ether-linked (O-)phosphatidylethanolamine and O-phosphatidylcholine from O-diacylglycerol overall and in TF lambs. Higher cholesterol levels could underlie adverse cardiometabolic outcomes in TF lambs, whereas suppressed PEMT pathway in TM lambs could lead to endoplasmic reticulum stress and defective lipid transport. These novel findings point to sex-specific effects of prenatal T excess on lipid metabolism in newborn lambs, a precocial ovine model of translational relevance.

Prenatal Androgen Excess Induces Multigenerational Effects on Female and Male Descendants

Background

It is still unelucidated how hormonal alterations affect developing organisms and their descendants. Particularly, the effects of androgen levels are of clinical relevance as they are usually high in women with Polycystic Ovary Syndrome (PCOS). Moreover, it is still unknown how androgens may affect males' health and their descendants.

Objectives

We aimed to evaluate the multigenerational effect of prenatal androgen excess until a second generation at early developmental stages considering both maternal and paternal effects.

Design And Methods

This is an animal model study. Female rats (F0) were exposed to androgens during pregnancy by injections of 1 mg of testosterone to obtain prenatally hyperandrogenized (PH) animals (F1), leading to a well-known animal model that resembles PCOS features. A control (C) group was obtained by vehicle injections. The PH-F1 animals were crossed with C males (m) or females (f) and C animals were also mated, thus obtaining 3 different mating groups: Cf × Cm, PHf × Cm, Cf × PHm and their offspring (F2).

Results

F1-PHf presented altered glucose metabolism and lipid profile compared to F1-C females. In addition, F1-PHf showed an increased time to mating with control males compared to the C group. At gestational day 14, we found alterations in glucose and total cholesterol serum levels and in the placental size of the pregnant F1-PHf and Cf mated to F1-PHm. The F2 offspring resulting from F1-PH mothers or fathers showed alterations in their growth, size, and glucose metabolism up to early post-natal development in a sex-dependent manner, being the females born to F1-PHf the most affected ones.

Conclusion

androgen exposure during intrauterine life leads to programing effects in females and males that affect offspring health in a sex-dependent manner, at least up-to a second generation. In addition, this study suggests paternally mediated effects on the F2 offspring development.

Maternal androgen excess increases the risk of pre-diabetes mellitus in male offspring in later life: a long-term population-based follow-up study

PURPOSE

Prenatal androgen exposure could be a source of early programming, leading to the development of cardiometabolic diseases in later life. In this study, we aimed to examine cardiometabolic disturbances in males exposed to maternal androgen excess during their prenatal life.

METHODS

In this prospective population-based study, 409 male offspring with maternal hyperandrogenism (MHA), and 954 male offspring without MHA, as controls, were included. Both groups of male offspring were followed from the baseline to the date of the incidence of events, censoring, or end of the study period, whichever came first. Age-scaled unadjusted and adjusted Cox regression models were applied to assess the hazard ratios (HR) and 95% confidence intervals (CIs) for the association between MHA with pre-diabetes mellitus (Pre-DM), type 2 diabetes mellitus (T2DM), pre-hypertension (Pre-HTN), hypertension (HTN), dyslipidemia, overweight, and obesity in the offspring of both groups. Statistical analysis was performed using the STATA software package; the significance level was set at P < 0.05.

RESULTS

A higher risk of Pre-DM (adjusted HR: 1.46 (1.20, 1.78)) was observed in male offspring with MHA after adjustment for potential confounders, including body mass index, education, and physical activity. However, no significant differences were observed in the risk of T2DM, Pre-HTN, HTN, dyslipidemia, overweight, and obesity in males with MHA compared to controls in both the unadjusted and adjusted models.

CONCLUSION

Maternal androgen excess increases the risk of Pre-DM in male offspring in later life. More longitudinal studies with long enough follow-up are needed to clarify the effects of MHA on the cardiometabolic risk factors of male offspring in later life.

Sheep as a model for neuroendocrinology research

Animal models remain essential to understand the fundamental mechanisms of physiology and pathology. Particularly, the complex and dynamic nature of neuroendocrine cells of the hypothalamus make them difficult to study. The neuroendocrine systems of the hypothalamus are critical for survival and reproduction, and are highly conserved throughout vertebrate evolution. Their roles in controlling body metabolism, growth and body composition, stress, electrolyte balance, and reproduction, have been intensively studied, and have yielded groundbreaking discoveries. Many of these discoveries would not have been feasible without the use of the domestic sheep (Ovis aries). The sheep has been used for decades to study the neuroendocrine systems of the hypothalamus and has become a model for human neuroendocrinology. The aim of this chapter is to review some of the profound biomedical discoveries made possible by the use of sheep. The advantages and limitations of sheep as a neuroendocrine model will be discussed. While no animal model can perfectly recapitulate a human disease or condition, sheep are invaluable for enabling manipulations not possible in human subjects and isolating physiologic variables to garner insight into neuroendocrinology and associated pathologies.

Hyperandrogenism and Polycystic ovary syndrome: Effects in pregnancy and offspring development

Polycystic ovary syndrome (PCOS) is one of the major endocrine disorders affecting women of reproductive age. Its etiology remains unclear. It is suggested that environmental factors, and particularly the intrauterine environment, play key roles in PCOS development. Besides the role of androgens in PCOS pathogenesis, exposure to endocrine disruptors, as is Bisphenol A, could also contribute to its development. Although PCOS is considered one of the leading causes of ovarian infertility, many PCOS patients can get pregnant. Some of them by natural conception and others by assisted reproductive technique treatments. As hyperandrogenism (one of PCOS main features) affects ovarian and uterine functions, PCOS women, despite reaching pregnancy, could present high-risk pregnancies, including implantation failure, an increased risk of gestational diabetes, preeclampsia, and preterm birth. Moreover, hyperandrogenism may also be maintained in these women during pregnancy. Therefore, as an altered uterine milieu, including hormonal imbalance, could affect the developing organisms, monitoring these patients throughout pregnancy and their offspring development is highly relevant. The present review focuses on the impact of androgenism and PCOS on fertility issues and pregnancy-related outcomes and offspring development. The evidence suggests that the increased risk of pregnancy complications and adverse offspring outcomes of PCOS women would be due to the factors involved in the syndrome pathogenesis and the related co-morbidities. A better understanding of the involved mechanisms is still needed and could contribute to a better management of these women and their offspring. This article is categorized under: Reproductive System Diseases > Molecular and Cellular Physiology Reproductive System Diseases > Environmental Factors.