Aldosterone Inhibits Uncoupling Protein-1, Induces Insulin Resistance, and Stimulates Proinflammatory Adipokines in Adipocytes

Abstract

Aldosterone is a mineralocorticoid hormone that regulates blood pressure and salt/water balance. Increased aldosterone levels are found in states of disturbed energy balance such as the metabolic syndrome. Adipose tissue has been recognized to play a pivotal role in the regulation of energy homeostasis. We investigated direct aldosterone effects on brown adipocyte function. Aldosterone dose-dependently inhibited expression of uncoupling protein-1 (UCP-1) by 30 % (p < 0.01). Furthermore, aldosterone dose-dependently impaired insulin-induced glucose uptake by about 25 % (p < 0.01). On a transcriptional level, mRNA of the proinflammatory adipokines leptin and monocyte chemoattractant protein-1 (MCP-1) was increased by 5,000 % and 40 %, respectively, by aldosterone exposure (p < 0.05). This study demonstrates that aldosterone directly impacts on major adipose functions including stimulation of proinflammatory adipokines.

Adipose tissue - Metabolic syndrome - Monocyte-chemoattractant protein-1

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