White adipose tissue : Storage and effector site for environmental pollutants

Summary White adipose tissue (WAT) represents a reservoir of lipophilic environmental pollutants, especially of those which are resistant to biological and chemical degradation – so-called persistent organic pollutants (POPs). Large amounts of different congeners and isomers of these compounds exhibit a variety of adverse biological effects. Interactions among different classes of compounds, frequently with opposing effects, complicate hazard evaluation and risk assessment. WAT is the key organ for energy homeostasis and it also releases metabolites into the circulation and adipokines with systemic effects on insulin sensitivity and fuel partitioning in muscles and other tissues. Its beneficial role is lost in obesity when excessive accumulation of WAT contributes to severe diseases, such as diabetes. POPs may crossroad or modulate the effect of endogenous ligands of nuclear transcription factors, participating in differentiation, metabolism and the secretory function of adipocytes. These mechanisms include, most importantly: i) endocrine disrupting potency