清肺排毒汤对大鼠慢性支气管肺炎气道炎症及免疫功能改善作用机制

Effect and Mechanism of Qingfei Paidu Decoction(清肺排毒汤)on Airway Inflammation and Immune Function in Rats with Chronic Bronchopneumonia

目的 探究清肺排毒汤对慢性支气管肺炎大鼠气道炎症及免疫功能的影响,并分析可能的机制。方法 50只大鼠随机分为对照组、模型组、清肺排毒汤低、高剂量组及阳性对照组,每组10只。其中清肺排毒汤低、高剂量组于模型建立成功后分别给予清肺排毒汤0.75、1.50 g·kg^(-1)·d^(-1)灌胃给药(连续4周),阳性对照组同时间给予胸腺肽混悬液灌胃处理,模型组及对照组于同时间分别给予等量生理盐水灌胃处理。酶联免疫吸附(enzyme-linked immunosorbent assay, ELISA)法检测大鼠血清、肺泡灌洗液中白介素-13(interleukin-13,IL-13)、白介素-8(interleukin-8,IL-8)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)水平;苏木精-伊红(hematoxylin-eosin, HE)染色观察大鼠肺组织病理学变化;测定大鼠脾脏指数、胸腺指数;免疫印迹法检测大鼠肺组织中通路蛋白水平兔抗鼠Toll样受体4(Toll-like receptor4,TLR4)、髓样细胞分化蛋白88(Myeloid differentiation primary response gene 88,MyD88)水平变化。结果 慢性支气管肺炎大鼠模型建立成功;与对照组比较,模型组大鼠血清IL-13、IL-8、TNF-α水平及TLR4、MyD88蛋白水平均升高,肺活量(forced vital capacity, FVC)、肺动态顺应性(Dynamic compliance, Cdyn)、血氧饱和度(SaO2)、动脉氧分压(PaO2)水平及脾脏指数、胸腺指数均降低(均P<0.05);与模型组比较,清肺排毒汤低、高剂量组及阳性对照组大鼠血清IL-13、IL-8、TNF-α水平及TLR4、MyD88蛋白水平均降低,FVC、Cdyn、SaO2、PaO2水平及脾脏指数、胸腺指数均升高(均P<0.05);且清肺排毒汤高剂量组、阳性对照组大鼠血清IL-13、IL-8、TNF-α水平及TLR4、MyD88蛋白水平均低于低剂量组,FVC、Cdyn、SaO2、PaO2水平及脾脏指数、胸腺指数均高于低剂量组(均P<0.05)。结论 清肺排毒汤对大鼠慢性支气管肺炎气道炎症及免疫功能具有改善作用,可能是通过抑制TLR4/MyD88通路的活化实现的。

Objective To explore the effect of Qingfei Paidu Decoction(清肺排毒汤)on airway inflammation and immune function in rats with chronic bronchopneumonia and analyze the possible mechanism.Methods Fifty rats were randomly divided into control group,model group,low and high dose groups of Qingfei Paidu Decoction and positive control group,with 10 rats in each group.The low and high dose groups of Qingfei Paidu Decoction were given 0.75 g·kg^(-1)·d^(-1) and 1.50 g·kg^(-1)·d^(-1) of Qingfei Paidu Decoction by gavage(for 4 weeks).The positive control group was given thymosin suspension by gavage at the same time,and the model group and control group were given the same amount of normal saline by gavage at the same time.The levels of interleukin-13(IL-13),IL-8 and tumor necrosis factor-α(TNF-α)in rat serum and alveolar lavage fluid were detected by enzyme-linked immunosorbent assay(ELISA).Hematoxylin eosin(HE)staining was used to observe the pathological changes of the rats lung.Spleen index and thymus index were measured.The levels of pathway protein,rabbit anti rat toll like receptor 4(TLR4)and myeloid cell differentiation protein 88(MyD88)were detected by Western blot.Results The rat model of chronic bronchopneumonia was successfully established.Compared with those of the control group,the serum levels of IL-13,IL-8 and TNF-αand TLR4 and MyD88 protein levels in the model group were increased.The values of forced vital capacity(FVC),dynamic compliance(Cdyn),SaO2,PaO2,spleen index and thymus index in the model group decreased(P<0.05).Compared with those of the model group,the serum levels of IL-13,IL-8 and TNF-αand TLR4 and MyD88 protein levels in the low and high dose groups of Qingfei Paidu Decoction and the positive control group were decreased.The values of FVC,Cdyn,SaO2,PaO2,spleen index and thymus index increased(P<0.05).The serum levels of IL-13,IL-8 and TNF-αand TLR4 and MyD88 protein levels in the Qingfei Paidu Decoction high dose group and positive control group were lower than those of the Qingfei Paidu Decoction low dose group.The values of FVC,Cdyn,SaO2,PaO2,spleen index and thymus index in the Qingfei Paidu Decoction high dose group and positive control group were higher than those in the low dose group(P<0.05).Conclusion Qingfei Paidu Decoction can improve airway inflammation and immune function in rats with chronic bronchopneumonia,which may be realized by inhibiting the activation of TLR4/MyD88 pathway.