Insulin Sensitizers: Thiazolidinediones

Insulin Sensitizers: Thiazolidinediones

• Main Mechanism:

  • Thiazolidinediones (TZDs), such as pioglitazone and rosiglitazone, are oral antidiabetic agents that improve insulin sensitivity primarily through the activation of peroxisome proliferator-activated receptor gamma (PPAR-γ), a nuclear receptor found predominantly in adipose tissue.

  • Upon binding to PPAR-γ, TZDs enhance the transcription of genes involved in glucose and lipid metabolism, promoting adipogenesis and increasing fatty acid uptake in peripheral tissues.

  • This mechanism reduces circulating free fatty acids, thereby improving insulin action in muscle and liver tissues.

  • Additionally, TZDs increase the secretion of beneficial adipokines like adiponectin, which further enhances insulin sensitivity and has anti-inflammatory effects.

  • By redistributing excess lipids to subcutaneous fat depots, TZDs mitigate insulin resistance associated with obesity, ultimately lowering blood glucose levels without increasing insulin secretion directly

Thiazolidinediones Examples

• Common Drugs (-glitazones; RPT):

  • Rosiglitazone (Avandia)

  • Pioglitazone (Actos)

  • Troglitazone: banned due to hepatotoxicity