In vitro activity: GSK3787 is a potent, selective and irreversible antagonist of PPARδ with pIC50 of 6.6 and good pharmacokinetic properties. It has no measurable affinity for hPPARα or hPPARγ. GSK3787 can antagonize PPARbeta/delta in vivo, thus providing a new strategy to delineate the functional role of a receptor with great potential as a therapeutic target for the treatment and prevention of disease. Although it responds to ligand activation to modulate the association of both PPAR-β/δ and PPAR-γ coregulator peptides, GSK3787 exhibits considerably higher antagonism of PPAR-β/δ than that of PPAR-γ.

Kinase Assay: GSK3787 is identified as a potent and selective hPPARδ ligand (pIC50=6.6) with no measurable affinity for hPPARα or hPPARγ (pIC50 < 5) in our standard in vitro ligand displacement assay. GSK3787 is inactive against hPPARα and hPPARγ in similar functional antagonist assays. GSK3787 fails to activate the receptor in a standard hPPARδ-GAL4 chimera cell-based reporter assay. GSK3787 is a selective PPARδ antagonist with equipotent species activity against the human and mouse receptor.

Cell Assay: GSK3787 irreversibly antagonizes human and mouse PPARδ that covalently modifies Cys249 within the ligand binding pocket. GSK 3787 completely antagonizes the activity of agonist GW501516 with a pIC50 of 6.9 and 94% maximal inhibition. GSK3787 (1 μM) effectively antagonizes the agonist GW0742 stimulated transcription of CPT1a and PDK4 in human skeletal muscle cells, and effectively antagonize the basal gene expression of CPT1a. GSK 3787 shows no effective antiproliferative activity against colorectal cancer cells. GSK3787 (1 μM) completely antagonizes 50 nM GW0742-induced PPARβ/δ-dependent Angptl4 gene expression in wild-type fibroblasts and in keratinocytes. GSK3787 (1 μM) largely antagonizes 50 nM GW0742-induced Angptl4 and Adrp mRNAs expression in skin cancer cell A341. GSK3787 (1 μM) largely antagonizes GW0742-induced Angptl4 mRNAs expression in cancer cell lines MCF7 (breast), Huh7 (liver), and HepG2 (liver) cells but not in H1838 or A549 cells (lung). GSK3787 (1 μM) largely antagonizes GW0742-induced increase of Adrp mRNA in Huh7 and HepG2 cells but not in H1838 cells. GSK3787 does not antagonize basal expression of either of these two PPARβ/δtarget genes in these cells. Neither GW0742 nor GSK3787 has any effect on cell proliferation of these cells at concentrations ranging from 0.1 to 10 μM.