Melatonin and the metabolic syndrome

Abstract

The ongoing worldwide obesity epidemic is paralleled by an elevated incidence of the metabolic syndrome, a disorder referred to as a clustering of metabolic abnormalities that increase the risk for cardiovascular disease and type 2 diabetes. Considered as a multifunctional molecule, the pineal gland hormone melatonin is also involved in body fat mass and energy metabolism regulation. A large body of evidence supports the beneficial effects of melatonin on the cardiovascular function in normal and pathophysiological conditions. However, melatonin's role in cardiovascular risk factors such as obesity and other related disorders including the metabolic syndrome needs further investigations, particularly in humans. This chapter will address the effects of melatonin on the metabolic syndrome focusing on obesity and insulin-resistant conditions. Since cardiovascular disease is the primary outcome of the metabolic syndrome, the effects of melatonin on cardiovascular function will be also described focusing on normal and pathological conditions. In view of the current knowledge, we aim to reveal the potential clinical relevance of melatonin or melatonin receptor agonists in the setting of obesity-induced metabolic syndrome.