PM2.5 Induced the Expression of Fibrogenic Mediators via HMGB1-RAGE Signaling in Human Airway Epithelial Cells

Figure 4

Effects of PM2.5 and HMGB1-RAGE signaling on NF-κB activity in HBECs. Cells were stimulated with PM2.5 (20 μg/ml) for 12, 24, and 48 h. (a) Western blot analysis showing that PM2.5 decreased the cytosolic levels of NF-κB and increased the nuclear levels after 24 and 48 h of PM2.5 stimulation; no significant difference was observed at 12 h of PM2.5 stimulation. (b) Cells were transfected with the HMGB1 siRNA or control siRNA for 48 h and subsequently stimulated with PM2.5 (20 μg/ml) for 48 h. Western blot analysis showing that cells transfected with the HMGB1 siRNA increased the cytosolic levels of NF-κB and attenuated nuclear NF-κB levels compared with cells stimulated with PM2.5. (c) Cells were pretreated with anti-RAGE antibodies (10 μg/ml) or IgG for 1 h and subsequently exposed to PM2.5 (20 μg/ml) for 48 h. Western blot analysis showing that cell pretreated with anti-RAGE antibodies increased the cytosolic levels of NF-κB and attenuated nuclear NF-κB levels compared with cells stimulated with PM2.5. The cytosolic NF-κB/tubulin and nuclear NF-κB/lamin B ratio of the control cells is set to 1. , compared with the control group. , compared with the PM2.5 group, n = 3.

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