Interleukin-8 Regulates The Expression Of MUC5B In Human Bronchial Mucosa Epithelial Cell Through The JAK2/STAT6 Ingnaling Pathway

Purpose:The purpose of this study was to investigate whether IL-8affected the transcription and translation of MUC5 B in bronchial mucosal epithelial cells and whether it regulated the expression of MUC5 B through the JAK2/STAT6 signaling pathway.Methods:1.Human bronchial mucosal epithelial cells(HBE135-E6E7)were cultured in vitro for 24 hours in serum-free medium before IL-8stimulation.According to the selection of stimulation with different IL-8concentrations,the experiments were divided into the following six groups: Group A: blank control group,Group B: 20ng/ml IL-8 group,Group C: 40ng/ml IL-8 group,Group D: 60ng/ml IL-8 group,Group E:80ng/ml IL-8 group,Group F: 160ng/ml IL-8 group.The MUC5 B protein content in each group was measured by ELISA.2.Human bronchial mucosal epithelial cells were cultured serum-free for 24 hours before IL-8 stimulation.According to the treatment time,the cells were divided into the following five groups:Group A: blank control group,Group B: 6h IL-8 group,Group C: 12 h IL-8 group,Group D: 24 h IL-8 group,and Group E: 48 h IL-8 group.The content of MUC5 B protein in each group was measured by ELISA.3.Human bronchial mucosal epithelial cells were cultured serum-free for 24 hours before IL-8 stimulation.with the treatment factor of JAK2 inhibitor AG490,they were divided into the following four groups: group A blank control group;group B: the optimal concentration group(160 ng/m L)of IL-8;group C:160 ng/m L IL-8+AG490;group D: AG490 group(50umol/l)for 48 h,The mRNA level of MUC5 B in each group was measured by RT-PCR,the protein level of MUC5 B in each group was measured by ELISA,and the protein levels of ρ-JAK2,ρ-STAT6,JAK2 and STAT6 in each group were measured by WB method.Results:1.By measuring the expression of MUC5 B in different IL-8concentration groups,it is found that IL-8 can stimulate the expression of MUC5 B in bronchial epithelial cells,and the expression of MUC5 B increases with the increase of IL-8 concentration.The relative expression of MUC5 B in 160ng/ml IL-8 group was the highest(16.6334±1.1277),with statistical significance(P<0.05).2.By measuring the expression of MUC5 B in different time groups,it was found that the relative expression of MUC5 B protein increased with the increase of time under the stimulation of certain concentration of IL-8.The relative expression of MUC5 B protein in 48 h group was the highest(16.6334±1.1277),and the result was statistically significant(P<0.05).3.After the JAK2 inhibitor AG490 was added,the protein content of JAK2/STAT6 pathway was measured.Compared with Group A,the protein content of ρ-STAT6 and ρ-JAK2 in Group B increased,and the protein content and mRNA expression of MUC5 B increased with statistical significance(P<0.05).Compared with group B,the protein content and expression of ρ-STAT6 and ρ-JAK2 in group C decreased,and the protein content and mRNA expression of MUC5 B decreased with statistical significance(P<0.05).The expression of non-phosphorylated STAT6 and JAK2 had no obvious change in each group.Conclusion:1.IL-8 can stimulate the expression of MUC5 B in bronchial mucosal epithelial cells.2.IL-8 may regulate the expression of MUC5 B through the JAK2/STAT6 pathway.