Figure 2.

PPARα and PPARγ regulate vascular and inflammatory cell functions. Many different, often contradictory effects have been ascribed to PPAR ligands in vascular, and inflammatory cells. PPARα, and γ are expressed in endothelial cells, monocytes/macrophages, and in the vascular smooth muscle cells of both medial and intimal layers. PPARα ligands inhibit smooth muscle cell production of inflammatory products, and causes macrophage apoptosis. PPARγ ligands (i) inhibit smooth muscle cell migration processes; (ii) inhibit monocyte/macrophage production of inflammatory enzymes (iNOS; inducible nitric oxide synthase; Gel-B, gelatinase B), cytokines, and scavenger receptor (SR)-A expression; (iii) induce monocyte/macrophages differentiation, and uptake of oxidized LDL; (iv) induce monocyte and endothelial cell apoptosis; (v), inhibit the expression of vascular endothelial cell growth factor receptors, endothelin-1 and urokinase expression in endothelial cells and, (vi) induce plasminogen activator inhibitor-1 expression in endothelial cells.