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Figure 1 Pioglitazone Reduces TNF-Induced VCAM-1 mRNA Expression in a Dose- and Time-Dependent Manner in HSVECs

(A) Northern blot analysis of tumor necrosis factor (TNF)-induced vascular cell adhesion molecule (VCAM)-1 messenger ribonucleic acid (mRNA) expression was performed on human saphenous vein endothelial cells (HSVECs) pre-treated in the absence or presence of pioglitazone (PIO) (18 h) at the concentrations shown before TNF stimulation (10 ng/ml, 10 h). The effects of the PPAR 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/glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA was quantified from the Northern blots seen in panel A (n = 3, ^#p < 0.05, TNF-induced vs. vehicle, *p < 0.05, pioglitazone/TNF vs. TNF alone, Mann-Whitney U test). (C) The time-dependent effects of pioglitazone exposure (10 µM) on TNF-induced VCAM-1 expression was tested in HSVECs using Northern blotting. Results are shown as a percent of the TNF 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 bovine aortic endothelial cells before TNF stimulation are shown (left). For comparison, the effect of the PPAR 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 TNF vs. vehicle; *p < 0.05 pioglitazone or WY14643 vs. TNF alone, Mann-Whitney U test).