The Role of Aldosterone in the Metabolic Syndrome
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The metabolic syndrome associates metabolic abnormalities such as insulin resistance and dyslipidemia with increased waist circumference and hypertension. It is a major public health concern, as its prevalence could soon reach 30% to 50% in developed countries. Aldosterone, a mineralocorticoid hormone classically involved in sodium balance regulation, is increased in patients with metabolic syndrome. Besides its classic actions, aldosterone and mineralocorticoid receptor (MR) activation affect glucose metabolism, inducing insulin resistance through various mechanisms that involve oxidative stress, inflammation, and downregulation of proteins involved in insulin signaling pathways. Aldosterone and MR signaling exert deleterious effects on the cardiovascular system and the kidney that influence the cardiovascular risk associated with metabolic syndrome. Salt load plays a major role in cardiovascular injury induced by aldosterone and MR signaling. Large multicenter, randomized clinical trials testing the beneficial effects of MR antagonists on cardiovascular events and mortality in patients with metabolic syndrome are needed.
KeywordsMetabolic syndrome Aldosterone Obesity Mineralocorticoid receptor Insulin resistance Salt load Cardiovascular fibrosis Glomerulosclerosis Hypertension
Source of Funding
The work of the authors was supported by Canadian Institutes of Health Research (CIHR) grants MOP37137, MOP82790, and MOP102606; a Canada Research Chair (CRC) on Hypertension and Vascular Research from the CIHR/CRC Program of the Government of Canada; the Canada Fund for Innovation (E.L.S.); and a Fellowship from the Heart and Stroke Foundation of Canada (M.B.).
No potential conflicts of interest relevant to this article were reported.
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