(A) Northern blot analysis of TNFα-induced VCAM-1 mRNA expression was performed on HSVECs pretreated in the absence or presence of pioglitazone (18 h) at the concentrations shown prior to TNFα stimulation (10 ng/mL, 10 h). The effects of the PPARα agonist WY14643 (100 µM) are provided for comparison. One representative Northern blot (n=3) is shown. (B). The effect of the pioglitazone concentrations on VCAM-1/GAPDH mRNA was quantified from the Northern blots above. (n=3, #p<0.05, TNFα-induced vs. vehicle, *p<0.05, pioglitazone/TNFα vs. TNFα alone, Mann-Whitney test). (C) The time dependent effects of pioglitazone exposure (10 µM) on TNFα-induced VCAM-1 expression was tested in HSVECs using Northern blotting. Results are shown as a percent of the TNFα effect alone at 3 h, mean ± SD (n = 3; *, p<0.05). (D) The effect of pioglitazone versus vehicle on the human VCAM-1 promoter transiently transfected into BAEC before TNFα stimulation are shown (left). For comparison, the effect of the PPARα agonist WY14643 on the VCAM-1 promoter is also shown (right). All responses were normalized to β-galactosidase (pCMV-β-Gal) (n = 3 per each treatment, #p<0.05 TNFα vs. vehicle; *p<0.05 pioglitazone or WY14643 vs. TNFα alone, Mann-Whitney test).