Background: Conditions of excess androgen in women, such as polycystic ovary syndrome (PCOS), often exhibit intergenerational transmission. One way in which the risk for PCOS may be increased in daughters of affected women is through exposure to elevated androgens in utero. Hyperandrogenemic conditions have serious health consequences, including increased risk for hypertension and cardiovascular disease. Recently, gut dysbiosis has been found to induce hypertension in rats, such that blood pressure can be normalized through fecal microbial transplant. Therefore, we hypothesized that the hypertension seen in PCOS has early origins in gut dysbiosis caused by in utero exposure to excess androgen. We investigated this hypothesis with a model of prenatal androgen (PNA) exposure and maternal hyperandrogenemia by single-injection of testosterone cypionate or sesame oil vehicle (VEH) to pregnant dams in late gestation. We then completed a gut microbiota and cardiometabolic profile of the adult female offspring. Results: The metabolic assessment revealed that adult PNA rats had increased body weight and increased mRNA expression of adipokines: adipocyte binding protein 2, adiponectin, and leptin in inguinal white adipose tissue. Radiotelemetry analysis revealed hypertension with decreased heart rate in PNA animals. The fecal microbiota profile of PNA animals contained higher relative abundance of bacteria associated with steroid hormone synthesis, Nocardiaceae and Clostridiaceae, and lower abundance of Akkermansia, Bacteroides, Lactobacillus, Clostridium. The PNA animals also had an increased relative abundance of bacteria associated with biosynthesis and elongation of unsaturated short chain fatty acids (SCFAs). Conclusions: We found that prenatal exposure to excess androgen negatively impacted cardiovascular function by increasing systolic and diastolic blood pressure and decreasing heart rate. Prenatal androgen was also associated with gut microbial dysbiosis and altered abundance of bacteria involved in metabolite production of short chain fatty acids. These results suggest that early-life exposure to hyperandrogenemia in daughters of women with PCOS may lead to long-term alterations in gut microbiota and cardiometabolic function.

Marrow adipose tissue (MAT) is unique with respect to origin, metabolism, and function. MAT is characterized with high heterogeneity which correlates with skeletal location and bone metabolism. This fat depot is also highly sensitive to various hormonal, environmental, and pharmacologic cues to which it responds with changes in volume and/or metabolic phenotype. We have demonstrated previously that MAT has characteristics of both white (WAT) and brown (BAT)-like or beige adipose tissue, and that beige phenotype is attenuated with aging and in diabetes. Here, we extended our analysis by comparing MAT phenotype in different locations within a tibia bone of mature C57BL/6 mice and with respect to the presence of sex steroids in males and females. We report that MAT juxtaposed to trabecular bone of proximal tibia (pMAT) is characterized by elevated expression of beige fat markers including Ucp1, HoxC9, Prdm16, Tbx1, and Dio2, when compared with MAT located in distal tibia (dMAT). There is also a difference in tissue organization with adipocytes in proximal tibia being dispersed between trabeculae, while adipocytes in distal tibia being densely packed. Higher trabecular bone mass (BV/TV) in males correlates with lower pMAT volume and higher expression of beige markers in the same location, when compared with females. However, there is no sexual divergence in the volume and transcriptional profile of dMAT. A removal of ovaries in females resulted in decreased cortical bone mass and increased volume of both pMAT and dMAT, as well as volume of gonadal WAT (gWAT). Increase in pMAT volume was associated with marked increase in Fabp4 and Adiponectin expression and relative decrease in beige fat gene markers. A removal of testes in males resulted in cortical and trabecular bone loss and the tendency to increased volume of both pMAT and dMAT, despite a loss of gWAT. Orchiectomy did not affect the expression of white and beige adipocyte gene markers. In conclusion, expression profile of beige adipocyte gene markers correlates with skeletal location of active bone remodeling and higher BV/ TV, however bone loss resulted from sex steroid deficiency is not proportional to MAT expansion at the same skeletal location.

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Cardiovascular disease is the leading cause of death in men and women within the United States. Individuals at risk for developing cardiovascular disease possess morbidity characteristic of metabolic dysfunction including diabetes, hypertension, and obesity. Previous studies have found that the origins of cardiovascular disease may arise from the prenatal environment and exposure to excess sex steroids such as testosterone produces adverse consequences that place male and female adult offspring at risk for the development of insulin resistance, infertility, obesity, and heart disease. However, the effects of excess testosterone on female cardiovascular function remains poorly understood. In this study, we hypothesized that a single‐injection of testosterone in the late gestation of Wistar rats would establish a metabolic phenotype characteristic of hypertension in adult female rats. Sixty‐six female Wistar rats were separated into two groups, vehicle and prenatal androgen (PNA), after weaning. We investigated the effect of excess testosterone on cardiovascular function and morphology with telemetry, echocardiogram, and immunohistochemistry. We also assessed insulin and glucose tolerance and utilized quantitative gene expression analysis to determine differential gene and protein expression. Our data suggest that the prenatal exposure to excess androgen alters systemic expression of genetic markers associated with diabetes and hypertension and negatively impacts cardiovascular function by increasing systolic and diastolic blood pressure. Overall, our results confirm that prenatal androgen exposure may negatively impact cardiovascular health of females in adulthood.

Thermoregulation is a physiological process by which a mammal regulates body temperature in response to its environment. Within the human body, thermoregulatory behaviors and metabolism are modulated by circulating metabolic factors. In our study, we tested the ability of the neuropeptide spexin, which shares sequence homology to galanin, to regulate these functions in female mice. Supraphysiological levels of spexin in C57BL/6 mice were insufficient to protect against diet-induced obesity after 50 days of treatment. Behavioral analysis of long-term spexin treatment appeared to modulate anxiety-like behaviors by promoting exploratory behaviors and thermoregulatory behaviors of nest building that ceased when animals were housed at thermoneutral temperatures. Upon examination of the molecular profile of brown and white adipose tissue, treatment disrupted the thermogenic profile of white adipose tissue, in which β3-adrenergic receptor expression was downregulated. Our results reveal novel functions for spexin as a modulator of thermoregulatory behaviors and adipose tissue metabolism.

In the last decade, neuropeptide Q or spexin (SPX) was implicated in central and peripheral functions including feeding suppression and lipid metabolism. To test whether spexin acts on brown and white adipose tissue, we performed subcutaneous micro-osmotic infusion of spexin in mice with diet-induced obesity. Our preliminary results indicate that spexin may differentially regulate biomarkers of adipogenesis and insulin sensitivity in brown and white adipose tissue. Spexin infusion increased interscapular brown adipose tissue mass and mRNA expression of adiponectin, fatty-acid binding protein 4, lipoprotein lipase, and C/EBP-⍺ in female C57BL/6 mice. Within gonadal white adipose tissue, spexin and PPAR-γ2 mRNA expression was upregulated while immunohistochemistry of gWAT revealed that β3-adrenergic receptor expression was significantly decreased while adipocyte diameter was increased. These results indicate that spexin infusion differentially regulates adipogenesis within brown adipose tissue by increasing BAT mass and increasing non-adrenergic regulation of adipogenesis within gonadal white adipose tissue.