Effect Of TLR4/PI3K Signaling Related Molecules In The Airway Smooth Muscle Cell Migration Induced By Airway Epithelium And The Mechanism

Objective: Bronchial asthma (asthma) is a kind of chronic airway diseases involved a variety of cytokines. The characteristic pathological changes of asthma are airway remodeling and airway inflammation.Airway remodeling is an important part of asthma, while its pathogenesis has not yet entirely clear. As a physical barrier, the bronchial epithelium not only decreases the function of barriers and protection, but also releases cytokines such as TNF-a, RANTES, IL-8 and so on when stimulated by various injury factors. The cytokines can induce migration of smooth muscle cells, which play an important role in airway remodeling in asthma.Toll-like receptors and phosphoinositide 3-kinases are involved in a variety of diseases and closely related with asthma.We could evaluate the condition of ASMCs more scientifically and comprehensively in a state of asthma to explore that TLR4/PI3K-related signaling molecules how to effect ASMCs migration function inducd by bronchial epithelium cells by directly observing the function of bronchial epithelium cells of control status and intervention status, and the effect of ASMCs migration induced by bronchial epithelium cells. Also, by building up rat asthma model, we attempt to explore that impact of Xiaoqinglong decoction on the expression of TLR4 and ASMCs migration to explore new ideas for treatment of asthma medicine.Methods: By using Immunohistochemistry, ELISA,Modified Boyden chamber and other techniques , and TNF-a,TLR4 antibody,PI3K inhibitor Ottawa Man penicillin (Wortmannin) and NF-κB inhibitor pyrrolidine dithio-amino-alkyl carboxylic acid (PDTC) and Xiaoqinglong decoction as as a tool for medicine to research on Cultured ASMCs, to explore the effect of TLR4/PI3K signaling related molecules in the airway smooth muscle cell migration induced by airway epithelium and the related mechanism.Results:⑴TNF-a groups compared with the normal ASMCs, IL-8 and RANTES secretion was significantly higher (P <0.01).⑵TNF-a groups compared with the normal control group, ASMCs migration induced by RTE culture supernatants was significantly higher (P<0.01), and the trend is consistent with that of the supernatant of IL-8 and RANTES levels.⑶TNF-α+TLR4 antibody groups,TNF-α+ Wortmannin group and TNF-α+PDTC group compared with the normal control group, ASMCs migration was significantly lower (P <0.01).⑷TNF-α+Wortmannin group+PDTC group compared with TNF-α+ Wortmannin group, ASMCs migration was significantly lower (P <0.01).⑸4 weeks of asthmatic model group, 8 weeks of asthmatic model group,4 weeks of Xiaoqinglong decoction group and 8 weeks of Xiaoqinglong decoction group compared with the normal control group, The WAt /Pi and WAm/Pi were significantly higher, while distance/Pi was shorter(P <0.01).⑹4 weeks of asthmatic model group and 4 weeks of Xiaoqinglong decoction group compared with 8 weeks of asthmatic model group, The WAt /Pi and WAm/Pi were significantly shorter, while distance/Pi was higher (P <0.05).⑺8 weeks of Xiaoqinglong decoction group compared with 4 weeks of asthmatic model group and 8 weeks of asthmatic model group, The WAt /Pi was significantly shorter, while distance/Pi was higher (P <0.05).⑻4 weeks of asthmatic model group, 8 weeks of asthmatic model group,4 weeks of Xiaoqinglong decoction group and 8 weeks of Xiaoqinglong decoction group compared with the normal control group, TLR4 and p-Akt expression were significantly higher (P <0.01).⑼4 weeks of asthmatic model group, 4 weeks of Xiaoqinglong decoction group and 8 weeks of Xiaoqinglong decoction group compared with 8 weeks of asthmatic model group TLR4 and p-Akt expression were significantly lower (P <0.01).Conclusions:⑴TNF-a could induce the secretion of IL-8 and RANTES and other chemokines by asthmatic airway epithelial cells which correlates to the concentration. that is involved in airway inflammation and remodeling.⑵Asthmatic airway epithelial cells may could induce ASMCs migration by secreting chemokines, such as IL-8 and RANTES.⑶TLR4,PI3K and NF-κB may be involved in ASMCs migration induced by airway epithelial cell. Asthmatic epithelial cells may secrete chemokines and other cytokines, which cause activation of TLR4-related signaling molecules resulting to migration of ASMCs, thereby increasing the airway remodeling of asthma .⑷TLR4 and p-Akt involve in the migration of ASMCs and Xiaoqinglong decoction may could inhibite ASMCs migration by inhibiting TLR4 and p-Akt expression so that it may play important role in asthmatic airway remodeling .