Adipocyte Aldosterone in Obstructive Sleep Apnea

Abstract

Aldosterone, a hormone synthesized by the adrenal glands, plays a pivotal role in regulating both blood pressure and electrolyte balance and may contribute to long term cardiovascular risk. Recent findings suggest that adipose tissue might serve as a source for aldosterone production and secretion. Patients suffering from obstructive sleep apnea (OSA) often exhibit elevated blood pressure levels and increased cardiovascular risk. Therefore, we sought to investigate whether increased aldosterone synthesis in fat tissue could contribute to the increase in hypertension and cardiovascular disease in OSA patients. To address this, we conducted a comparative analysis of adipocyte aldosterone level in OSA patients versus Age and BMI matched healthy individuals. Our data revealed no significant differences in aldosterone content between the two groups. Further examination involved measuring the expression of the key enzyme CYP11B2 responsible for aldosterone synthesis. We observed comparable expression levels of CYP11B2 in both the OSA and control groups. To corroborate these findings, we isolated stromal vascular fraction (SVF) from human fat tissues. The SVF cells were cultured in preadipocyte medium and subjected to normoxia and intermittent hypoxia (IH), mimicking OSA conditions as per established protocol. Subsequent analysis of aldosterone levels in cell lysates and conditioned medium revealed no significant differences. Similarly, in vitro examination of CYBP11B2 expression was not different in normoxic versus IH conditions. In conclusion, our study did not discern significant differences in adipocyte aldosterone production and secretion between patients with OSA and matched control subjects, nor in human preadipocytes under normoxic versus IH conditions.