Oleuropein as an inhibitor of peroxisome proliferator-activated receptor gamma.

ABSTRACT: Oleuropein, the major phenolic compound found in olive leaves and oil, exerts antioxidant, anti-inflammatory and anti-atherogenic effects and suppresses the adipocyte differentiation in vitro. Herein, we characterized molecular mechanisms underlying the anti-adipogenic effects of oleuropein on 3T3-L1 cells and adipocytes derived from stromal-vascular fraction of dorsolumbar and gonadal fat dissected from mice. We found that oleuropein (>100 ?M) decreased viability of preadipocytes proliferating in vitro and did not exerted any cytotoxic effects in post-confluent cells after induction of differentiation. Oleuropein (>100 ?M) inhibited adipocyte differentiation, suppressed gene expression of peroxisome proliferator-activated receptor ? (PPAR?), CCAAT-/enhancer-binding protein ?, sterol regulatory element-binding transcription factor 1c and fatty acid synthase. Furthermore, we tested ability of oleuropein to regulate of PPAR?-, PPAR?- or PPAR?-/PPAR?-mediated ?-lactamase expression in appropriate reporter gene assays. Oleuropein between 10 and 400 ?M concentrations did not affect activity of PPAR? or PPAR?/?. Contrary, PPAR? activity, either basal or rosiglitazone activated, was inhibited by oleuropein. Our data suggest that oleuropein exerts anti-adipogenic effect through direct inhibition of PPAR? transcriptional activity.

SUBMITTER: Svobodova M 

PROVIDER: S-EPMC3896615 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature