Examination of the effects of the PPAR‐delta agonist GW501516 on the levels of Perilipin‐5 expression in cultured cells

Perilipin‐5 (also known as MLDP, or OXPAT), a member of the PAT family of proteins, is a lipid droplet‐binding protein, expressed in oxidative tissue. It is regulated by ligand‐activated transcription factors known as Peroxisome Proliferator‐Activated Receptors (PPARs). Recently, a PPAR‐δ modulator, GW501516, was developed that promotes the up‐take of glucose in skeletal muscle tissue and the oxidation of fatty acids. Previous studies have shown that perilipin‐5 expression can be induced using PPAR‐α and ‐γ agonists. The purpose of this project is to see if perilipin‐5 expression can also be induced by a PPAR‐δ agonist. This would create an ideal and novel tissue culture model system for the study and manipulation of perilipin‐5. CHO and C2C12 cells were considered. Results of colorimetric blots, thus far, have shown an increase in the size and intensity of bands of the treated cells on western blots. Additionally, the current data shows that at least two proteins detected by the perilipin‐5 antibody are increased significantly, estimated at nearly three‐fold, by treatment with the drug. Based on these results, it can be concluded that GW501516 is affecting protein expression.