三步序贯法对激素撤减过程中哮喘气道重塑模型大鼠肺泡灌洗液内TGF-β1/Smad信号通路相关指标浓度的影响

Effects of three-step sequential therapy on the concentrations of relevant parameters in TGF-β1/Smad signal pathway among asthma rats during steroid withdrawal

目的观察中药三步序贯法对哮喘模型大鼠激素撤减过程中肺泡灌洗液内生长转化因子-β1(TGF-β1)/Smad信号通路相关指标浓度的影响。方法将150只雄性SD大鼠随机分为正常对照组、气道重塑组、地塞米松组、普米克令舒组及三步序贯组。模型建立方法:以卵蛋白100 mg加氢氧化铝100 mg致敏,1%卵蛋白激发,自激发之日开始,于激发前30 min给予地塞米松0.5 mg/kg腹腔注射,连续2周,从第3周开始,按每周0.1 mg/kg速度递减地塞米松用量,至第7周地塞米松全部撤除。三步序贯组在地塞米松干预基础上,于实验第15~28天(地塞米松撤前期)给予第一步方颗粒(以滋阴清热、化痰降逆为法)灌胃,第29~63天(地塞米松撤中期)给予第二步方颗粒(以调补阴阳、活血化痰为法)灌胃,第64~77天(地塞米松撤后期)给予第三步方颗粒(以温阳和血、调畅气机为法)灌胃,每日1次。各组于实验流程第28、63、77天末次激发2 h后取肺泡灌洗液行酶联免疫吸附法检测,比较各组灌洗液TGF-β1/Smad信号通路相关指标的浓度变化。结果在撤减过程中,与正常对照组比较,气道重塑组和地塞米松组TGF-β1、Smad2浓度均升高(P<0.05),Smad3显著升高(P<0.01),Smad7浓度降低(P<0.05),与地塞米松组比较,三步序贯组TGF-β1、Smad2及Smad3降低(P<0.05),Smad7浓度升高(P<0.05)。结论中药三步序贯法对哮喘模型大鼠撤减激素过程中气道重塑的阻抑作用可能是通过对TGF-β1/Smad信号传导通路的调控来发挥的。

Objective To observe the influence of three-step sequential therapy on the TGF-β1/Smad signal pathway in rats with asthma during steroid withdrawal. Methods One hundred and fifty male SD rats were randomly divided into blank control group,airway remodeling group,hexadecadrol group,pulmicortrespules group and three-step sequential treatment group. The rat models were established by using sensitization of ovalbu-min（ OVA）（ 100 mg） and aluminum hydroxide（ 100 mg）. The models were stimulated by using 1% OVA,and from the third week,hexadecadrol（ 0. 5 mg/kg） was injected intraperitoneally on the first 30 min before stimulation for 2 consecutive weeks. The dosage of hexadecadrol was reduced at a rate of 0. 1 mg/kg per week,and it was stopped on the 7 th week. Rats in the three-step sequential therapy group received extra gavage administration of the first-stage formula（ yin-nourishing,heat-clearing,phlegm-resolving and qi-downbearing） on the 15 thto 28 thday,followed by second-step formula（ yin-yang regulating tonifying,blood-activating and phlegm-resolving） on the 29 thto63 rdday,and the third-step formula（ yang-warming and blood-harmonizing,qi-regulating） on the 64 thto77 thday. The alveolar lavage fluid of rats were obtained on the 28 th,63 rd,and 77 thday after 2 hours of the last stimulation,and the relevant parameters of TGF-β1/Smadsignal pathway were measured by using enzyme linked immunosorbent assay. Results In the process of steroid withdrawal,compared with the blank control group,the concentration of TGF-β1,Smad2 of rats in hexadecadrol group and airway remodeling group were higher（ P〈0. 05）; Smad3 were significantly higher（ P〈0. 01） and Smad7 were lower（ P〈0. 05）. Compared with hexadecadrol group,the concentration of TGF-β1,Smad2 and Smad3 of rats in the three-step sequential therapy group decreased（ P〈0. 05） and the concentration of Smad7 increased（ P〈0. 05）. Conclusion Three-step sequential therapy could inhibit airway remodeling of rats in the process of steroid withdrawal,possibly though regulating the TGF-β1/Smadsignal pathway.