Review : Adipose tissue : passive sump or active pump ?

Recent discoveries suggest that adipose tissue can synthesise and secrete mediators that contribute to the pathogenesis of type 2 diabetes mellitus and cardiovascular disease, leading to the concept of ‘adipose tissue as an endocrine organ’. These mediators include tumour necrosis factor-α, interleukin-6, adiponectin, resistin, plasminogen activator inhibitor type 1 and angiotensin II. They modify the activity of regulatory enzymes in adipocyte metabolism, alter the release of non-esterified fatty acids and affect glucose uptake. They may also have direct actions on the vascular endothelium. The diverse effects of these mediators support the notion that inflammation plays a role in metabolic and vascular disease, at least in part via adipocyte-derived cytokines.