RETN and metabolic syndrome: The most relevant point from these observations may be related to the complex relationship of the different pathways, cytokines and adipocyte-derived mediators driving inflammation in RA patients with MetS; as an example, proinflammatory cytokines such as tumor necrosis factor alpha are involved in the pathogenesis of insulin resistance while resistin (an adipocyte-derived mediator) also plays an important role in the inflammatory cascade and undergoes a dramatic reduction after anti-tumor necrosis factor alpha therapy [49].