Troglitazone, a PPAR-γ activator prevents endothelial cell adhesion molecule expression and lymphocyte adhesion mediated by TNF-α

Abstract

BACKGROUND: Cytokine mediated induction of the mucosal addressin cell adhesion molecule-1(MAdCAM-1) expression is associated with the onset and progression of inflammatory bowel disease (IBD). RESULTS: Using western blotting and cell-based ELISA, we show in this study that troglitazone, an activator of the peroxisome proliferator-activated receptor-gamma (PPAR-gamma), widely used in the treatment of diabetes, has as well recently been highlighted as protective in models of inflammation and cancer. We found that troglitazone (10-40 microM), significantly reduced the TNF-alpha (1 ng/ml) mediated induction of endothelial MAdCAM-1 in a dose-dependent manner, achieving a 34.7% to 98.4% reduction in induced MAdCAM-1. Trogliazone (20 microM) reduced TNF-alpha induced VCAM-1, ICAM-1 and E-selectin expression. Moreover, troglitazone significantly reduced alpha4beta7-integrin dependent lymphocyte adhesion to TNF-alpha cultured endothelial cells. CONCLUSIONS: These results suggest that PPAR-gamma agonists like troglitazone may be useful in the clinical treatment of IBD.