To Investigate The Mechanism Of Yangyin Qingfei Decoction In Regulating SMPP Inflammation Based On TLR-2/MyD88 Signaling Pathway

Purpose:Establish mouse model of severe Mycoplasma pneumoniae pneumonia(SMPP)with high load of Mycoplasma pneumoniae(MP),and screen the factors influencing the establishment of mouse model of severe Mycoplasma pneumoniae pneumonia(SMPP)by orthogonal experiment;treat SMPP mice with modified Yangyin Qingfei Decoction,and explore the effect of modified Yangyin Qingfei Decoction on the expression of TLR-2/My D88 signal pathway related factors in SMPP mouse model,objective to clarify the mechanism of modified Yangyin Qingfei Decoction in the treatment of SMPP target.Material and method:The mouse SMPP model was established by nasal instillation of MP with high load,and the model was identified and evaluated by comparing with that of normal MP.A three-factor two-level orthogonal experimental design was used to infect mice with MP to prepare pneumonia models,and the serum levels of interleukin-6(IL-6)and tumor necrosis factor-?(TNF-?)were evaluated The indicators were scored comprehensively,and the effects of three different factors and their levels on the formation of the SMPP model in mice were observed.After the successful establishment of the model,the next step of drug intervention experiment was carried out.Methods:120 BALB/c mice were randomly divided into normal group,model group,azithromycin group,modified Yangyin Qingfei Decoction group,modified Yangyin Qingfei Decoction+azithromycin group.On the 3rd,7th,10th and 14th day,6 mice in each group were randomly selected and sacrificed.The lung pathology of mice was observed by HE staining.The m RNA expression levels of Toll like receptor(TLR-2),myeloid differentiation molecule 88(My D88)and nuclear factor kappa B(NF-?b),and serum interleukin-8(IL-8)level were detected by ELISA and q PCR.Results:1.At each time point,the lung index of the two model groups was higher than that of the normal group,and the lung index of the high-load mice was higher than that of the normal-load group on the 5th,7th and 10th day(p<0.05).The pathological scores,IL-6 and TNF-?levels of mice in the high-load group were higher than those in the normal-load group at all time points(p<0.05),suggesting that the SMPP model of mice was successfully established.2.Orthogonal experiment to optimize the SMPP model preparation experiment,except for the model group,the other three groups all established the SMPP model,and the MP infection degree of the model three groups was relatively serious.The result of visual analysis shows that the important order of factors affecting the preparation of SMPP is challenge method>MP bacterial solution concentration>challenge days.3.IL-8 in serum was detected by ELISA,and TLR-2,My D88,and NF-?B in lung tissue were detected by PCR.The results showed that compared with the normal group,on the 3rd,7th,10th,and 14th day after MP infection,TLR-2,The expressions of My D88,NF-?B and IL-8 all increased(p<0.05).Among them,NF-?B peaked on the 3th days,TLR-2 and IL-8peaked on the 7th day,and My D88 peaked on the 10th day.4.After drug intervention,the expressions of TLR-2,My D88,NF-?B,and IL-8 in the three administration groups decreased compared with the model group,but were still higher than the normal group(p<0.05);Compared with other treatment groups,the Yangyin Qingfei Decoction combined with azithromycin group had better curative effect,and the difference was statistically significant(p<0.05).Conclusion:1.Using 1×10¹⁰CCU/ml Mycoplasma pneumoniae bacterial solution to drip the nose continuously for 3 days,a mouse model of severe Mycoplasma pneumoniae pneumonia can be established,and the important factors influencing the SMPP model are the method of attack>MP load>the number of days of attack.2.Yangyin Qingfei Modified Decoction can reduce lung inflammation in SMPP model mice,and the combined effect of azithromycin is better.3.Yangyin Qingfei Modified Decoction can regulate the TLR-2/My D88 signaling pathway,thereby inhibiting the expression of its related factors TLR-2,My D88,NF-?B,and IL-8,which may be a target for the treatment of SMPP.