Role Of TLR4/TRIF Signaling Pathways In Airway Mucus Hypersecretion In Asthmatic Mice

Part 1 Effects of Inhaled LPS on Inflammation and Mucus Hypersecretion in the Airway in Athmatic MiceObjective To investigate the inflammation and mucus hypersecretion in airway of asthma mice and LPS stimulation of asthmatic mice. Methods Thirty clean BALB/c mice were randomly devided into three groups:asthma model group (AST group n=10), LPS＋asthma model group (LPS group n=10), control group (NS group,n=10). Asthmatic model group was sensitized and challenged with ovalbumin (OVA), LPS＋asthma model group like asthma group and addition of LPS stimulation atomization, control group was sensitized and challenged with normal sodium. Total cells and differential inflammatory cells were counted in bronchoalveolar lavage fluid (BALF), the levels of 1L-4 and TNF-a in BALF were determined by ELISA, the pathomorphological Changes in the lung were observed by hematoxylin-eosin staining(HE), the goblet cell of airway wall was observed by AB-PAS staining, the expression of Mucin-5ac (Muc5ac) and TLR4 in airway were observed by immunohistochemical staining, The expressions of Muc5ac mRNA and TLR4 mRNA in lung tissue were observed by real time fluorescence quantitative reverse transcription polymerase (RT-PCR), the content of Muc5ac protent and TLR4 protent in lung tissue were observed by Western-blotting. Results Total cells, eosinophil, monocytes and lymphocyte cells in BALF, the levels of IL-4,TNF-a in BALF, the hyperpLPSia of goblet cell in the airway wall, and the expression of Muc5ac in lung tissue of AST or LPS group were obviously higher than those in control group(P<0.05). On airway inflammation and airway mucus hypersecretion in lung tissue of LPS group were obviously higher than those in AST group (P<0.05). Conclusions lymphocyte and eosinophil cells obviously observed in the airway inflammation of asthmatic mice which were sensitized and challenged with ovalbumin (OVA). The goblet cell metapLPSia and airway mucus hypersecretion were observed in asthmatic mice. They are related closely. on Airway inflammation and mucus hypersecretion in lung tissue of LPS group were obviously higher than those in AST group, it may stimulated inflammatory mediators be activated and generated with vivo for LPS。Party 2 Role of TLR4/TRIF Signaling in Mucus Hypersecretion in Asthmatic Mice Treated with DynasoreObjective To investigate the effects of TLR4/TRIF signal transduction pathway on Muc5ac in the airway of asthmatic mice, And the change which treated with TLR4/TR1F signal transduction pathway antogonist Dynasore. Methods Fifty clean BALB/c mice were randomly divided into LPS＋asthmatic group(LPS group, n=10), dexamethasone treatment group(DEX group, n=10), Polymyxin B treatment group(PMB group, n=10), Dynasore treatment group(DYN group, n=10), vehicle-control(dimethyl sulfoxide, DMSO) group (DMSO group, n=10), Total cells and differential inflammatory cells were counted in BALF, the levels of IL-4 and TNF-a in BALF were determined by ELISA, the pathomorphological Changes in the lung were observed by hematoxylin-eosin staining(HE), the goblet cell of airway wall was observed by alcian blue/periodic acid schiff (AB-PAS) staining, the expressions of Mucin 5ac(Muc5ac) and TLR4 in lung tissue were observed by immuneohistochemical staining (1HC) and WB, the expressions of Muc5ac mRNA,TLR4 mRNA and IFN-βmRNA in lung tissue were observed by RT-PCR. Results For indicators, vehicle-control group compared with LPS+asthmatic group (P>0.05). The total cells, eosinophil and lymphocyte cells in BALF, the levels of IL-4,TNF-αin BALF, IHC and WB in the goblet cell of airway wall, the expression of Muc5ac and TLR4 positive staining IOD in the airway and the expression of Muc5ac.. TLR4 and IFN-βmRNA lung tissue obviously decreased in Dynasoe treatment group,Polymyxin B treatment group and DEX treatment group which compared with LPS＋asthmatic group (P<0.05). Conclusions The current studys suggests that TLR4/TR1F signal transduction pathway may induce airway inflammation, upgrate Muc5ac mRNA and Muc5ac hypersecretion in airway of asthmatic mice. Dynasore may inhibit inflammation and mucus hypersecretion in airway of mice with asthma, which were mediated by TLR4/TR1F signal transduction pathway.