PPAR-gamma

Class

Thiazolidinedione (insulin sensitizer)

Peroxisome proliferator-activated receptor gamma (PPAR-gamma) is a nuclear receptor, a protein that resides largely in the cell nucleus and, once activated, binds directly to DNA to change which genes are turned on. It is most abundant in fat tissue, where it acts as the master regulator of adipocyte (fat cell) formation and function, and it also influences glucose and lipid handling in muscle and liver. Thiazolidinediones are small molecules that bind PPAR-gamma and activate it, promoting the differentiation of new, smaller fat cells and shifting the balance of hormones and fatty acids released by fat tissue toward a state that makes muscle, liver, and fat cells more responsive to insulin. This improved insulin sensitivity lowers blood glucose without directly stimulating insulin secretion, distinguishing this mechanism from drugs that act on the pancreas. Because insulin resistance is a central feature of type 2 diabetes and related metabolic disorders, PPAR-gamma activation has been a long-standing strategy for addressing the underlying metabolic dysfunction rather than only its glucose symptom. The same receptor pathway also has relevance to conditions marked by chronic inflammation and abnormal lipid metabolism, since PPAR-gamma activity influences immune cell behavior and lipid storage more broadly.