Effect Of Ultrashort Wave On TLR4/NF-κB Signaling Pathway In Lipopolysaccharide-induced Lung Inflammation In Rats

Objective:To investigate the effect of ultrashort wave in pneumonia.To explore the the possible mechanisms of ultrashort wave on lung tissue,and further investigate the mRNA and protein expressions for several important components of TLR4 / NF-kappa B signaling pathways in the rats,lung infection that induced by the LPS.Methods:45 3-month-old male SD rats with a body mass of 220-250 g were randomly divided into three groups(n=15 per group): sham operation control group(control group),pneumonia model group(pneumonia group),pneumonia with ultra-short wave treatment group(ultra-short wave group).The rats were made aspiration pneumonia model by intratracheal injection LPS in group and ultra-short wave group,and the rats in the control group were treated with equal dose of normal saline.The rats in the ultrashort wave group began to receive ultrashort wave treatment on the day after surgery,once a day for 15 minutes,and the treatment course was 5 days.No intervention was performed in the control group and the pneumonia group rats.Experimental rats were sacrificed on the day after the last ultrashort wave treatment.HE staining,semi-quantitative histopathological scoring and wet/dry weight ratio(W/D)of the lung tissues were performed.Serum inflammatory factors(IL-1β,Il-10,TNF-α,TGF-β)were analyzed by using ELISA system.Immunohistochemistry was used to detect the level of TLR4 in lung tissue.RT-PCR and Western blot were used to detect the mRNA and protein expressions of P-IκB,p65,NLRP3 in the TLR4/NF B signaling pathway.Results:1.HE staining showed that,compared with the control group,the lung tissues of rats in the pneumonia group were severely damaged,with a large number of inflammatory cells infiltrating,and the semi-quantitative pathological score of lung tissues was significantly increased(P < 0.01).The lung tissue injury in the ultrashort wave group was significantly improved compared with that in the pneumonia group,and the semi-quantitative pathological score of the lung tissue was lower than that in the pneumonia group(P < 0.01).2.The ratio of wet/dry weight of lung tissues in the pneumonia group was higher than that in the control group(P<0.05),but there was no significant difference between the pneumonia group and the ultrashort wave group(P > 0.05).3.Compared with the control group,the expression levels of IL-1 and TNF-α in the serum of rats in the pneumonia group were increased(P < 0.01,P < 0.01),while the expression levels of IL-10 and TGF-β were decreased(P < 0.01).Compared with the pneumonia group,the expression levels of IL-1 and TNF-α in serum of rats in the ultra-short wave group were decreased(P < 0.01,P < 0.01),while the expression levels of IL-10 were increased(P < 0.05),and there was no significant difference in TGF-β expression levels(P > 0.05).4.Compared with the control group,the TLR4 expression level of rats in the pneumonia group was increased(P < 0.01).Compared with the pneumonia group,TLR4 expression level was decreased in the ultrashort wave group(P < 0.05).5.Compared with the control group,the mRNA and protein levels of p-IκB,P65 and NLRP3 were increased in the pneumonia group(P < 0.01,P < 0.01,P < 0.01).Compared with the pneumonia group,the mRNA and protein levels of p-IκB,P65 and NLRP3 in the ultrashort wave group were decreased(P < 0.05,P < 0.01,P < 0.01).Conclusion:1.Ultrashort wave can reduce the degree of lung inflammation.2.Ultrashort wave may regulate the TLR4/ NF-κB signaling pathway to reducing the degree of pulmonary inflammation by maintaining the relative stability of proinflammatory factors/anti-inflammatory factors3.Ultrashort wave may reduce the damage of lung tissue by inhibiting the expression of NLRP3.