MC4R and type 2 diabetes mellitus: Recent evidence suggests that imbalanced autonomic nervous system output causes the simultaneous occurrence of T2DM, dyslipidaemia, hypertension, and visceral obesity: MC4R neurons in amygdala, arcuate nucleus, paraventricular nucleus, nucleus suprachiasmaticus, and anterior pituitary regulate food intake (Turek et al., 2005; Buijs and Kreier, 2006), energy expenditure (Balthasar et al., 2005) or influence vasoconstriction via angiotensin mediated activity of the sympathetic nervous system (Greenfield et al., 2009).