Figure 1.

KPR inhibits ICAM-1 expression induced by LPS via HO-1 upregulation in HPAEpiCs. (A) HPAEpiCs were pretreated with KPR (10 μM) for 1 h, and then incubated with LPS (20 µg/mL) for the indicated time intervals. The protein levels of ICAM-1 and HO-1 were determined by Western blot using GAPDH as a loading control. (B) Cells were pretreated with KPR (10 μM) for 1 h, and then incubated with LPS (20 μg/mL) for 4 h. The levels of ICAM-1 and HO-1 mRNA were determined by real-time PCR. (C) Cells were transfected with scrambled or HO-1 siRNA, treated with KPR (10 μM) for 1 or 8 h, and then incubated with LPS (20 μg/mL) for 16 h. The levels of ICAM-1 and HO-1 protein were determined by Western blot using GAPDH as a loading control. (D) Cells were pretreated KPR for 1 h, then incubated by ZnPPIX for 1 h, and finally stimulated with LPS for 16 h. In addition, cells were incubated with LPS for 16 h and treated with an anti-ICAM-1 neutralizing antibody (2 μg/mL) for 1 h. The adhesion of THP-1 cells (displayed in green) was measured. Data are expressed as mean ± SEM (n = 5), analyzed with one way ANOVA and Dunnett’s post hoc test. # p < 0.01, as compared with the cells exposed to vehicle alone; or significantly different as indicated.