To Study The Interventional Mechanism Of Baicalin On Lipopolysaccharide-induced HBE16 Cell Hyper-production Via MAPKs Signaling Pathway

Objective:Based on the MAPKs signaling pathway,the intervention mechanism of baicalin on the hypersecretion of lipopolysaccharide-induced mucus in HBE16 cells was studied at the cellular level.Method : Cck-8(Cell counting kit-8)method was used to explore the optimal treatment time and concentration in HBE16 cell stimulated by LPS(Lipopolysaccharid-ides)to construct an in vitro mucus hypersecretion model,and the maximum intervention concentration of baicalin on HBE16 cells was also explored.Appropriate treatment concentration was selected according to the maximum intervention concentration of baicalin,and the intervention groups were divided into control group,LPS group,and baicalin group(three baicalin concentrations were 10g/ml,50g/ml and 100 g/ml).The expression of MUC5 ac in cell culture supernatant was detected by ELISA(Enzyme Linked immuno-sorbent Assay).RT-PCR(reverse transcription-polymerase chain reaction)method to detect cellular RNA MUC5 ac mRNA expression level.Western Blotting method was used to detect the expression levels of phospho ErK(extracellular regulated protein kinases),phospho-p38,phospho-jnk(c-jun N-terminal kinase)in the signaling pathway of mitogen-activated protein kinases.Results:The expression level of MUC5 ac was detected by ELISA,and the results showed that: compared with the control group,the MUC5 ac protein level in the LPS group was increased(P < 0.05).Compared with the LPS group,except for 6 hours(P > 0.05),the protein levels of MUC5 ac in the baicalin intervention groups were decreased(P < 0.05).the difference of MUC5 ac in baicalin group was the most significant at 24 and 48 hours(P < 0.01).At the same observation time point,baicalin showed a dose-dependent relationship to the secretion inhibition of MUC5 ac except at the 6-hour time point.The mRNA expression of MUC5 ac was detected by RT-PCRmethod,and the results showed that: compared with the control group,the mRNA expression level of MUC5 ac in LPS group was significantly increased(P < 0.01)except at 6 hours.Compared with LPS group,the expression level of MUC5 ac mRNA in baicalin intervention groups were significantly decreased(P < 0.01).Moreover,the expression level of MUC5 ac mRNA in the baicalin intervention groups at 12,24 and 48 hours was dose-dependent,especially at 24 hours.The expression of key MAPK proteins was detected by Western Blotting.Results:compared with the control group,phospho-ErK,phospho-p38,phospho-JNK protein expressions in LPS group were significantly increased(P < 0.01).Compared with LPS group,the expressions of phospho-ErK,phospho-p38,and phospho-JNK in baicalin intervention groups were all decreased(P < 0.05),especially in 50μg/ml and100 μg/ml groups.Conclusion : Baicalin can inhibit the expression of MUC5 ac mRNA and the secretion of MUC5 ac in human airway epithelial cells induced by LPS via regulating the expression of phospho-erk,phospho-p38,and phospho-jnk in MAPK signaling pathway,thus play to inhibit airway mucus hypersecretion.