Comparison of the transcriptomic profile of intestinal epithelial cells (Caco-2 cells) treated with different PPARgamma agonists

Peroxisome proliferator-activated receptor-gamma (PPARgamma) is a nuclear receptor highly expressed by colonic epithelial cells. It plays a key role in gut homeostasis and metabolism regulation. We previously showed that PPARgamma has a role in the action of aminosalycilates (5-ASA), one of the oldest anti-inflammatory agents used in the treatment of inflammatory bowel disease. These data have prompted us to develop novel analogues of 5-ASA with greater PPARgamma-activating properties (GED). The various PPARgamma ligands appear to have some markedly different effects, some of which can induce adverse effects. The transcriptomic profiles induced by various families of PPARgamma ligands are very poorly known and especially in intestinal epithelial cells. Hence, the objectives of the present project is to compare the gene expression profile induced by GED, 5-ASA, and pioglitazone in Caco-2 cells, in order to better understand these compounds’ modes of action, to discover potential new PPARgamma target genes in intestinal epithelial cells and to explain the efficacy difference between GED and 5-ASA. 1 million of cells (plated in 6 wells plates) were treated with GED (1 mM for AGO samples and 30mM for GED samples), 5-ASA (30 mM), or pioglitazone (1 M) in DMEM without serum. When necessary, the vehicle DMSO (Sigma) was used as control (Ctrl). Serum deprivation was used 16 hours prior to stimulation in order to synchronize the cells. Experiment was done with 6 replicates for each treatment. After 24 hrs of stimulation, the wells were rinsed three times with sterile PBS at 4 C. Total RNA were extracted with the Nucleospin RNA kit (Macherey-Nagel, Hoerdt, France).