Fat and Beyond: The Diverse Biology of PPARγ

Abstract
The nuclear receptor PPARγ is a ligand-activated transcription factor that plays an important role in the control of gene expression linked to a variety of physiological processes. PPARγ was initially characterized as the master regulator for the development of adipose cells. Ligands for PPARγ include naturally occurring fatty acids and the thiazolidinedione (TZD) class of antidiabetic drugs. Activation of PPARγ improves insulin sensitivity in rodents and humans through a combination of metabolic actions, including partitioning of lipid stores and the regulation of metabolic and inflammatory mediators termed adipokines. PPARγ signaling has also been implicated in the control of cell proliferation, atherosclerosis, macrophage function, and immunity. Here, we review recent advances in our understanding of the diverse biological actions of PPARγ with an eye toward the expanding therapeutic potential of PPARγ agonist drugs.