L-165041 is a cell permeable PPARβ (peroxisome proliferator-activated receptor β) agonist which induces adipocyte differentiation in NIH-PPARβ cells. In addition, this ligand reduces lipid accumulation in the liver and decreases total hepatic cholesterol and triglyceride content. Studies suggest that L-165041 affects mRNA expression by reducing the expression of PPARγ, apolipoprotein B, interleukin 1 β (IL-1β), and interleukin-6, while increasing the expression of PPARβ, lipoprotein lipase (LPL), and ATP-binding cassette transporter G1 (ABCG1). Furthermore, upon binding to PPARβ L-165041 suppresses vascular smooth muscle proliferation and migration by inhibiting the cell cycle, specifically blocking G1 to S phase progression and repressing the phosphorylation of retinoblastoma protein (Rb) in rats. Alternate studies suggest that L-165041 suppresses the cytokine-induced expression of VCAM-1 (vascular cell adhesion molecule-1) and increases UCP3 (uncoupling protein 3) gene expression in L6 myotubes. L-165041 is an activator of PPAR beta.
