Androgen excess is one of the most common endocrine disorders of reproductiveaged women, affecting up to 20% of this population. Women with elevated androgens often exhibit hyperinsulinemia and insulin resistance. The mechanisms of how elevated androgens affect metabolic function are not clear.Hyperandrogenemia in a dihydrotestosterone (DHT)-treated female mouse model induces whole body insulin resistance possibly through activation of the hepatic androgen receptor (AR). We investigated the role of hepatocyte AR in hyperandrogenemia-induced metabolic dysfunction by using several approaches to delete hepatic AR via animal-, cell-, and clinical-based methodologies.

We have previously found that in utero exposure to excess maternal cortisol (1 mg/kg/day) in late gestation increases the incidence of stillbirth during labor and produces fetal bradycardia at birth. In the interventricular septum, mitochondrial DNA (mt-DNA) was decreased, and transcriptomics and metabolomics were consistent with altered mitochondrial metabolism. The present study uses transcriptomics to model effects of increased maternal cortisol on fetal biceps femoris. Transcriptomic modeling revealed that pathways related to mitochondrial metabolism were downregulated, whereas pathways for regulation of reactive oxygen species and activation of the apoptotic cascade were upregulated. Mt-DNA and the protein levels of cytochrome C were significantly decreased in the biceps femoris. RT-PCR validation of the pathways confirmed a significant decrease in SLC2A4 mRNA levels and a significant increase in PDK4, TXNIP, ANGPTL4 mRNA levels, suggesting that insulin sensitivity of the biceps femoris muscle may be reduced in cortisol offspring. We also tested for changes in gene expression in diaphragm by rt-PCR. PDK4, TXNIP, and ANGPTL4 mRNA were also increased in the diaphragm, but SLC2A4, cytochrome C protein, and mt-DNA were unchanged. Comparison of the change in gene expression in biceps femoris to that in cardiac interventricular septum and left ventricle showed few common genes and little overlap in specific metabolic or signaling pathways, despite reduction in mt-DNA in both heart and biceps femoris. Our results suggest that glucocorticoid exposure alters expression of nuclear genes important to mitochondrial activity and oxidative stress in both cardiac and skeletal muscle tissues, but that these effects are tissue-specific.

Previous studies have suggested that increases in maternal cortisol or maternal stress in late pregnancy increase the risk of stillbirth at term. In an ovine model with increased maternal cortisol over the last 0.20 of gestation, we have previously found evidence of disruption of fetal serum and cardiac metabolomics, and of expression of genes related to mitochondrial function and metabolism in biceps femoris, diaphragm and cardiac muscle. The present studies were designed to test for effects of chronically increased maternal cortisol on gene expression and metabolomics in placentomes near term. We hypothesized that changes in placenta may underlie or contribute to the alterations in fetal serum metabolomics, and thereby contribute to changes in striated muscle metabolism. Placentomes were collected from pregnancies in early labor (143±1 d gestation) of control ewes (n=7) or ewe treated with cortisol (1 mg/kg/d iv; n=5) starting at day 115 of gestation. Transcriptomics and metabolomics were performed using an ovine gene expression microarray (Agilent 019921) and HR-MAS NMR, respectively. Multi-omic analysis indicates that amino acid metabolism, particularly of branched chain amino acids and glutamate occur in placenta; changes in amino acid metabolism, degradation or biosynthesis in placenta were consistent with changes in valine, isoleucine, leucine and glycine in fetal serum. The analysis also indicates changes in glycerophospholipid metabolism and suggests changes in ER stress and antioxidant status in the placenta. These findings suggest that changes in placental function occurring with excess maternal cortisol in late gestation may contribute to metabolic dysfunction in the fetus at birth.

Sodium dichloroacetate (DCA) is an investigational drug that shows promise in the treatment of acquired and congenital mitochondrial diseases, including myocardial ischemia and failure. DCA increases glucose utilization and decreases lactate production, and so may also have clinical utility in reducing lactic acidosis during labor.In the current study we test the ability of DCA to cross the placenta and be measured in fetal blood following intravenous administration to pregnant ewes during late gestation and labor. Sustained administration of DCA to the mother over 72h achieved pharmacologically active levels of DCA in the fetus and decreased fetal plasma lactate concentrations. Multi-compartmental pharmacokinetics modeling indicated drug metabolism in the fetal and maternal compartments is best described by the DCA inhibiting lactate production in both compartments, consistent with our finding that the hepatic expression of the DCA-metabolizing enzyme GSTZ1 was decreased in the ewes and their fetuses exposed to the drug. We provide the first evidence that DCA can cross the placental compartment to enter the fetal circulation, inhibit its own hepatic metabolism in the fetus, leading to increased DCA concentrations and decreased fetal plasma lactate concentrations during its parenteral administration to the mother. Significance statementThis study was the first to administer sodium dichloroacetate (DCA) to pregnant animals (sheep). It showed that DCA administered to the mother can cross the placental barrier and achieve concentrations in fetus sufficient to decrease fetal lactate concentrations. Consistent with findings reported in other species, DCA-mediated This article has not been copyedited and formatted. The final version may differ from this version.

Cortisol administration during late gestation in ewes, modeling maternal stress, resulted in transcriptomic changes suggesting altered maturation and metabolic changes to the offspring heart. This study investigates the effects of cortisol on epicardial adipose tissue (EAT), a visceral fat pad associated with adverse cardiovascular conditions in adults. Pregnant ewes were treated with either 1 mg·kg−1·day−1 cortisol from 115 days gestation to term and EAT collected from term fetuses (control: n = 8, maternal cortisol 1 mg·kg−1·day−1: n = 6). To compare the effects of cortisol to the normal maturation in EAT, we also modeled the normal changes in gene expression in EAT at the transition from in utero to postnatal life using the EAT from control fetuses and from two-week-old lambs (control: n = 7). Transcriptomic modeling was used to identify pathways altered by maternal cortisol overexposure. Transcriptomic modeling confirmed the brown fat phenotype of EAT at term and a transition toward white fat at 2 wk of age in EAT of control fetuses/lambs and highlighted a role of immune responses, including complement coagulation, and serotonin in this transition. Maternal cortisol (1 mg·kg−1·day−1) increased the lipid peroxidation product 4-hydroxynonenal in EAT of term fetuses but did not affect the number of activated macrophages or size of the lipid droplets in the depot; transcriptomics suggested an earlier metabolic maturation of EAT via, in part, increased immune responses.