Imiglitazar (TAK559) is a potent PPAR-β/δ receptor agonist with hypoglycemic effects.

TAK-559, a partial agonist for hPPARg1, achieves approximately 68% of the maximal activation obtained with rosiglitazone, a known PPARγ agonist. Significant activation of PPARγ is observed at a high concentration (10 μM) of TAK-559. Competition-binding assays using radiolabeled ligand indicate that the transactivation of all hPPAR subtypes by TAK-559 is a result of direct binding of TAK-559 to each subtype. TAK-559 also recruits the coactivator SRC-1 to both hPPARγ1 and hPPARα, and dissociates the corepressor NCoR from both hPPARγ1 and hPPARα[1].
In the presence of 10 μM TAK-559, TNFα- or IL-1β-induced THP-1 cell attachment to cultured endothelial cells is significantly reduced. The secretion of monocyte chemoattractant protein-1 (MCP-1) from endothelial cells is reduced by 36%, accompanied by decreased mRNA expression in the cells. Furthermore, the proliferation and migration of cultured smooth muscle cells are significantly decreased in the presence of TAK-559[3].

During TAK-559 treatment, significant elevation of circulating high-density lipoprotein (HDL) cholesterol levels is observed, characterized by an increase in large HDL particles and a decrease in small dense HDL particles. Concurrently, plasma triglyceride and apolipoprotein B-100 levels decrease, while apolipoprotein A-I increases. Hyperinsulinemia and insulin resistance are significantly corrected with the highest dose of 3.0 mg/kg per day in these prediabetic monkeys. Additionally, no adverse effects on representative liver function parameters are observed during the study period[2].