Thiazolidinediones and inflammation

Thiazolidinediones (TZDs) are selective ligands of peroxisome-proliferator-activated receptor gamma increasingly used in the treatment of type 2 diabetes. Both in vitro and in vivo studies provide evidence that TZDs have anti-inflammatory properties. TZDs inhibit macrophage activation and decrease inflammatory cytokine expression and release in macrophage and monocyte. In vivo, treatment with TZDs decreases circulating mononuclear cells nuclear NF-kB content while increasing, in the same cells, expression of IkB, an NK-kB inhibitor. Furthermore, TZD treatment results in decreased plasma levels of inflammation and cardiovascular risk markers such as CRP, MMP9, PAI-1 and sCD40 in both obese and type 2 diabetic patients. Finally, TZDs induce synoviocyte apoptosis and reduce secretion of TNF alpha, IL-6 and IL-8 in synoviocyte from rheumatoid arthritis patients. TZDs might thus be considered for use in clinical trials targeting prevention of atherosclerosis and cardiovascular diseases and in pilot trials exploring the possibility that TZDs might help in the treatment of rheumatic diseases.