LEP and type 2 diabetes mellitus: It is known that leptin and adiponectin present opposite effects on insulin resistance and subclinical inflammation, whilst leptin can upregulate pro-inflammatory cytokines, such as IL-6 and TNF-α, both molecules being closely related to insulin resistance and T2DM, while adiponectin, through its capacity to downregulate the expression and release of several pro-inflammatory immune mediators, shows anti-inflammatory properties.