桑苏饮调控TLR4通路抑制哮喘大鼠气道炎症

Inhibitory Effect of Sangsuyin on Airway Inflammation in Asthmatic Rats by Regulating TLR4 Pathway

目的:探讨桑苏饮调控Toll样受体4(TLR4)通路对哮喘大鼠气道炎症的抑制作用。方法:48只SD大鼠中选取40只建立哮喘模型,并按照随机数表法等分为模型组,地塞米松组,桑菊饮低、中、高剂量组5组,剩余8只SD大鼠作为空白组。地塞米松组予以0.005 g·kg^(-1)灌胃,桑苏饮低、中、高剂量组分别予以2.1,4.2,8.4 g·kg^(-1)桑苏饮灌胃(给药体积0.01 L·kg^(-1)),模型组和空白组分别予以给药体积0.01 L·kg^(-1)灌胃生理盐水,均每天1次,共7 d。比较干预后各组大鼠过敏反应分级;酶联免疫吸附测定法(ELISA)检测各组大鼠干预后血清,支气管肺泡灌洗液(BALF)白细胞介素-1β(IL-1β),肿瘤坏死因子-α(TNF-α),γ-干扰素(IFN-γ)水平;苏木精-伊红(HE)染色观察各组肺组织病理改变,比较肺组织炎症细胞浸润评分;实时荧光定量聚合酶链式反应(Real-time PCR)检测各组肺组织TLR4,核转录因子-κB(NF-κB)mRNA表达;蛋白免疫印迹法(Western blot)检测各组肺组织TLR4,NF-κB蛋白表达及磷酸化(p)-NF-κB水平。结果:模型组过敏反应分级、肺组织病理改变较空白组加重,其余各组较模型组均有所减轻;模型组血清,BALF IL-1β,TNF-α水平均高于空白组,其余各组均低于模型组(P<0.01);模型组血清,BALF IFN-γ水平均低于空白组,其余各组均高于模型组(P<0.05,P<0.01);模型组肺组织炎症细胞浸润评分,肺组织TLR4,NF-κB mRNA与蛋白表达,p-NF-κB蛋白水平均高于空白组,其余各组均低于模型组(P<0.01),差异有统计学意义。结论:桑苏饮可抑制哮喘大鼠过敏反应、肺组织病变和气道炎症,可能是通过抑制TLR4通路,下调TLR4,NF-κB mRNA与蛋白表达,降低p-NF-κB水平实现。

Objective:To investigate the inhibitory effect of Sangsuyin on airway inflammation in asthmatic rats by regulating the Toll-like receptor 4(TLR4)pathway.Method:Forty-eight SD rats were randomly divided into a normal group(n=8)and an experimental group(n=40).Asthma model was induced in the rats of the experimental group which were further divided into the following five groups according to a random number table:a model group,a dexamethasone group(0.005 g·kg^(-1)),and low-(2.1 g·kg^(-1)),medium-(4.2 g·kg^(-1)),and high-dose(8.4 g·kg^(-1))Sangsuyin groups.The drugs were all dissolved in normal saline at0.01 L·kg^(-1).The rats in the model group and the normal group received normal saline(ig)at 0.01 L·kg^(-1).The drug treatment was carried out once per day,for a total of 7 days.The grades of allergic reactions were compared among the groups after intervention.The levels of interleukin-1β(IL-1β),tumor necrosis factor-α(TNF-α),and interferon-γ(IFN-γ)in serum and bronchoalveolar lavage fluid(BALF)were detected by enzyme-linked immunosorbent assay(ELISA).Hematoxylin-eosin(HE)staining was used to observe the pathological changes of lung tissues,and the inflammatory cell infiltration scores of lung tissues were compared.The mRNA expression of TLR4 and nuclear factor-κB(NF-κB)was detected by quantitative real-time fluorescence-based reverse-transcription polymerase chain reaction(Real-time PCR).The expression of TLR4,NF-κB,and the level of phosphorylated NF-κB(p-NF-κB)were detected by Western blot.Result:The success rate of modeling was 95.00%.Compared with the normal group,the model group showed a higher grade of allergic reaction and more severe pathological changes of lung tissues,and the groups with drug intervention exhibited relieved conditions.The levels of IL-1βand TNF-αin the serum and BALF were higher in the model group than in the normal group,and lower in the groups with drug intervention than in the model group(P<0.01).The level of IFN-γin the serum and BALF was lower in the model group than in the normal group,and higher in the groups with drug intervention than in the model group(P<0.05,P<0.01).The inflammatory cell infiltration score,mRNA and protein expression of TLR4 and NF-κB,and the mRNA level of p-NF-κB were higher in the model group than in the normal group,and lower in the groups with drug intervention than in the model group(P<0.01).Conclusion:Sangsuyin could inhibit allergic reactions,lung tissue lesions,and airway inflammation in asthmatic rats.It is speculated that this effect is achieved by inhibiting the TLR4 pathway,down-regulating the mRNA and protein expression of TLR4 and NF-κB,and reducing the level of p-NF-κB.angsuyin can inhibit allergic reaction,lung tissue lesions and airway inflammation in asthmatic rats.It is speculated that this effect is achieved by inhibiting TLR4 pathway,down regulating the mRNA and protein expression of TLR4,NF-κB,and reducing the levels of p-NF-κB.