What is the mechanism of action (MOA) of Thiazolidinediones?

• A. PPAR activator, sensitizes adipocytes to insulin
• B. Inhibits DPP-4 enzyme
• C. Stimulates insulin secretion from pancreatic cells
• D. Reduces glucose reabsorption in the kidneys

Answer: (A)

Thiazolidinediones (TZDs) act primarily as agonists of the peroxisome proliferator-activated receptor gamma (PPAR-γ). This mechanism of action is significant because it enhances the sensitivity of adipocytes (fat cells) to insulin. By activating PPAR-γ, TZDs promote the transcription of genes involved in glucose and lipid metabolism. This results in an increase in insulin sensitivity, particularly in muscle and fat tissues, leading to improved glucose uptake and utilization in the body.

Additionally, their role in lipid metabolism helps to lower free fatty acid levels and positively influences the overall metabolic profile of individuals with insulin resistance, which is commonly seen in conditions like type 2 diabetes. Thus, the mechanism encompassing both insulin sensitivity and metabolic regulation through PPAR activation is central to the therapeutic effect of thiazolidinediones.