The MUC5B Mucin Is Involved in Paraquat-Induced Lung Inflammation

Figure 7

NAC involved in the PQ-induced ERK/JNK MAPK-NF-κB-MUC5B signaling pathway and attenuated MUC5B expression and cell inflammation. Cells were preincubated with 10 mM NAC for 2 h and then treated with 50 μM PQ for 30 min. (a) Phosphorylation levels of ERK, JNK, p38, and p65 were detected by Western blot analysis. Quantitative data are provided. (b-d) The addition of NAC efficiently suppressed the proteins ERK, JNK, and p65 phosphorylation level. (e) However, there was no significantly changes on p38 phosphorylation. (f) Cells were preincubated with various concentrations of NAC for 2 h and then treated with 50 μM PQ for 24 h. Cell viability assay was checked by CCK-8 assays. The cell viability was not changed neither by the PQ nor by the NAC treatment. (g, h) TNF-α and IL-6 levels in the cell culture supernatants were analyzed by ELISA. The expression levels of TNF-α and IL-6 were dramatically decreased after NAC. (i) MUC5B mRNA was analyzed by qRT-PCR technique and was suppressed by NAC treatment. (j) MUC5B protein levels were analyzed by dot blot ELISA; samples were duplicate in vertical line. (k) Compared to time PQ group, MUC5B protein levels were significantly decreased in the NAC treatment group. When compared with the siRNA and NAC groups, there was no significant difference from the suppression inflammatory cytokine level or MUC5B level between the single NAC treatment group and with the siRNA group. The data are shown as the of three different experiments. , , compared with the no-treatment group; , , compared with the PQ group. The data are shown as the of three different experiments. , , compared with the no-treatment group; , , compared with the PQ group.

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