A compound-based proteomic approach discloses 15-ketoatractyligenin methyl ester as a new PPAR? partial agonist with anti-proliferative ability.

ABSTRACT: Proteomics based approaches are emerging as useful tools to identify the targets of bioactive compounds and elucidate their molecular mechanisms of action. Here, we applied a chemical proteomic strategy to identify the peroxisome proliferator-activated receptor ? (PPAR?) as a molecular target of the pro-apoptotic agent 15-ketoatractyligenin methyl ester (compound 1). We demonstrated that compound 1 interacts with PPAR?, forms a covalent bond with the thiol group of C285 and occupies the sub-pocket between helix H3 and the ?-sheet of the ligand-binding domain (LBD) of the receptor by Surface Plasmon Resonance (SPR), mass spectrometry-based studies and docking experiments. 1 displayed partial agonism of PPAR? in cell-based transactivation assays and was found to inhibit the AKT pathway, as well as its downstream targets. Consistently, a selective PPAR? antagonist (GW9662) greatly reduced the anti-proliferative and pro-apoptotic effects of 1, providing the molecular basis of its action. Collectively, we identified 1 as a novel PPAR? partial agonist and elucidated its mode of action, paving the way for therapeutic strategies aimed at tailoring novel PPAR? ligands with reduced undesired harmful side effects.

SUBMITTER: Vasaturo M 

PROVIDER: S-EPMC5259791 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature