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Aldosterone is considered to be a link between hypertension and obesity; obese individuals have high serum levels of very low-density lipoprotein (VLDL). VLDL has been shown to induce aldosterone production in multiple adrenal zona glomerulosa models, mediated in part by phospholipase D (PLD). PLD is an enzyme that hydrolyzes phosphatidylcholine to produce phosphatidic acid (PA), a lipid second messenger that can also be dephosphorylated by lipin to yield diacylglycerol (DAG), yet another lipid signal. However, it is unclear which of the two lipid second messengers, PA or DAG, underlies PLD’s mediation of aldosterone production. We hypothesized that the key signal produced by PLD (indirectly) is DAG such that PLD mediates VLDL-induced aldosterone production via lipin-mediated metabolism of PA to DAG. To assess the role of lipin in VLDL-induced aldosterone production, lipin-1 was overexpressed (using an adenovirus) or inhibited (using propranolol) in HAC15 cells followed by treatment with or without VLDL. Lipin-1 overexpression enhanced the VLDL-stimulated increase in CYP11B2 expression (by 75%), and lipin-1 inhibition decreased the VLDL-stimulated increase in CYP11B2 expression (by 66%). Similarly, the VLDL-stimulated increase in aldosterone production was enhanced by lipin-1 overexpression (182%) and was decreased by lipin inhibition (80%). Our results are suggestive of DAG being the key lipid signal since manipulating lipin-1 levels/activity affects VLDL-stimulated steroidogenic gene expression and ultimately, aldosterone production. Our study warrants further investigation into VLDL-stimulated steroidogenic signaling pathways which may lead to the identification of novel therapeutic targets, such as lipin-1 and its downstream pathways, to potentially treat obesity-associated hypertension. [ABSTRACT FROM AUTHOR]

Objective: To examine the anthropometric, and metabolic connections of 17-hydroxypregnenolone in the normo- and hyperandrogenemic polycystic ovary syndrome phenotypes. Materials and methods: This cohort study was conducted at the Julio Muller University Hospital, Cuiabá, Brazil, between January 2014 and July 2016, and 91 normal cycling healthy women, 46 normoandrogenemic and 147 hyperandrogenemic, patients with polycystic ovary syndrome (PCOS) were enrolled according to the Rotterdam criteria. Several anthropometric, biochemical and hormonal parameters were properly verified and correlated with 17-hydroxypregnenolone (17-OHPE) concentrations. Results: 17-OHPE was higher in hyperandrogenemic PCOS than in normoandrogenemic PCOS and in control groups (P = 0.032 and P < 0.001, respectively). In healthy controls, 17-OHPE was positively associated with glucose, free estrogen index, DHEAS and negatively associated with compounds S. In normoandrogenemic PCOS patients, 17-OHPE presented positive correlations with VAI, LAP, cortisol, insulin and HOMA-IR. In the hyperandrogenemic group, 17-OHPE presented significant negative correlations with most anthropometric parameters, HOMA-IR, HOMA %B, estradiol, free estrogen index (FEI), C-peptide, and TG levels and positive correlations with HOMA-S and high-density lipoprotein cholesterol (HDL-C), sex-hormone binding globulin (SHBG), androstenedione (A4) and dehydroepiandrosterone (DHEA). Regarding hyperandrogenemic PCOS, and using a stepwise multiple regression, only HOMA-S and WHR were retained in the model (R2 = 0.294, P < 0.001). Conclusion: 17-OHPE exhibited different relationships with anthropometric, and biochemical parameters in PCOS patients, depending on the androgen levels. In PCOS subjects with high androgen concentrations, 17-OHPE was negatively associated with most anthropometric parameters, particularly with those used as markers of adipose tissue dysfunction and frequently employed as predictors of cardiovascular disease risk; otherwise, 17-OHPE was positively associated with HDL-C and HOMA-S in this patients. Future studies are required to evaluate the clinical implications of these novel findings.

Objective: To examine the anthropometric, and metabolic connections of 17-hydroxypregnenolone in the normo- and hyperandrogenemic polycystic ovary syndrome phenotypes., Materials and Methods: This cohort study was conducted at the Julio Muller University Hospital, Cuiabá, Brazil, between January 2014 and July 2016, and 91 normal cycling healthy women, 46 normoandrogenemic and 147 hyperandrogenemic, patients with polycystic ovary syndrome (PCOS) were enrolled according to the Rotterdam criteria. Several anthropometric, biochemical and hormonal parameters were properly verified and correlated with 17-hydroxypregnenolone (17-OHPE) concentrations., Results: 17-OHPE was higher in hyperandrogenemic PCOS than in normoandrogenemic PCOS and in control groups ( P  = 0.032 and P  < 0.001, respectively). In healthy controls, 17-OHPE was positively associated with glucose, free estrogen index, DHEAS and negatively associated with compounds S. In normoandrogenemic PCOS patients, 17-OHPE presented positive correlations with VAI, LAP, cortisol, insulin and HOMA-IR. In the hyperandrogenemic group, 17-OHPE presented significant negative correlations with most anthropometric parameters, HOMA-IR, HOMA %B, estradiol, free estrogen index (FEI), C-peptide, and TG levels and positive correlations with HOMA-S and high-density lipoprotein cholesterol (HDL-C), sex-hormone binding globulin (SHBG), androstenedione (A4) and dehydroepiandrosterone (DHEA). Regarding hyperandrogenemic PCOS, and using a stepwise multiple regression, only HOMA-S and WHR were retained in the model ( R 2  = 0.294, P  < 0.001)., Conclusion: 17-OHPE exhibited different relationships with anthropometric, and biochemical parameters in PCOS patients, depending on the androgen levels. In PCOS subjects with high androgen concentrations, 17-OHPE was negatively associated with most anthropometric parameters, particularly with those used as markers of adipose tissue dysfunction and frequently employed as predictors of cardiovascular disease risk; otherwise, 17-OHPE was positively associated with HDL-C and HOMA-S in this patients. Future studies are required to evaluate the clinical implications of these novel findings., (© 2017 The authors.)