贵州苗药杆努尽烟对慢性支气管炎模型大鼠肺组织MyD88蛋白表达的影响

Effects of L.Pauciflorus on chronic bronchitis model rats' expression of pulmonary tissue MyD88

(1)目的基于TLR4-MyD88-NF-κB信号通路,研究贵州苗药杆努尽烟对慢性支气管炎大鼠肺组织MyD88蛋白表达水平及支气管、肺组织炎症状况的影响。(2)方法 SD雄性大鼠60只,体质量(200±20)g,随机分为空白对照组,模型对照组,阳性对照组,杆努尽烟水提液高剂量组(8g/kg)、中剂量组(4g/kg)、低剂量组(2g/kg),每组10只。除空白对照组外,其余5组均采用烟熏和脂多糖气管滴注方法建立慢性支气管炎大鼠模型。造模成功后,杆努尽烟水提液高、中、低剂量组分别给予8g/kg、4g/kg、2g/kg(按生药计)的杆努尽烟水提液进行灌胃,阳性对照组给予桂龙咳喘宁1g/kg,空白对照组及模型组灌以等体积生理盐水,1次/d,连续给药28天,观察杆努尽烟水提液对大鼠咳嗽、气喘症状的缓解作用。采用Western Blot法测定肺组织MyD88蛋白表达,通过HE染色并于光镜下观察大鼠支气管、肺组织病理变化。(3)结果给药28天后,杆努尽烟水提液中、低剂量组大鼠MyD88含量与空白对照组相比差异有统计学意义(P<0.01),高剂量组与空白对照组相比差异有统计学意义(P<0.05);杆努尽烟水提液高剂量组大鼠MyD88含量与模型对照组相比均显著降低,差异有统计学意义(P<0.01);中、低剂量组大鼠MyD88含量与模型对照组相比差异有统计学意义(P<0.05)。(4)结论苗药杆努尽烟治疗慢性支气管炎有助于控制炎症反应,减轻气管、支气管及肺泡组织炎症,降低MyD88的蛋白含量,有效抑制MyD88蛋白的表达,下调TLR4-MyD88-NF-κB通路表达水平,从而改善气道及肺部的炎症状况;其中高剂量组与中、低剂量组相比,有明显下降,表明其抗炎效果呈剂量依赖性,较高的杆努尽烟剂量可带来更好的抗炎效果。

Objective With the TLR4-MyD88-NF-κB signaling pathway,study on the mechanism of L.Pauciflorus on the expression of MyD88 and the inflammation of bronchi and pulmonary tissue in chronic bronchitis model rats.Methods A total of 60 SD male rats with body weight of（200±20）g were randomly divided into six groups,normal control group,model group,positive control group,treatment groups respectively with high dosage group（8 g/kg）、middle dosage group（4 g/kg）and low dosage group（2 g/kg）,10 rats in each groups.Established the chronic bronchitis model rats by combination of fumigation and endotracheal instillation of LPS.After the successful establishment of the model,the high,middle and low dosage group were given L.Pauciflorus of 8 g/kg、4 g/kg、2 g/kg.The positive control group was given guilongkechuanning capsule of 1 g/kg.The normal control group and model group were given the same volume of physiological saline.Every group was treated for 28 days,once a day.Observed the effect of water extract of L.Pauciflorus on relieving cough and asthma symptoms in rats.Used the method of Western Blot to observe the ratsbronchi and pulmonary pathological changes.Observed the ratsbronchi and pulmonary pathological changes under optical microscope by HE staining.Results After 28 days of treatment,there were very significant differences of the middle、low dosage group and the normal control group in expression of MyD88（P 〈0.01）,the significant difference between the high dose group and the normal control group（P 〈0.05）.And the expression of MyD88 in the high dose group was a lot decreased than that in model group（P 〈0.01）,the significant difference between the middle、low dosage group and control group（P 〈0.05）.Conclusion L.Pauciflorus is helpful to control inflammatory reaction,reduce the tracheal,bronchial and alveolar inflammation,decrease the expression of MyD88,inhibit the express of MyD88,down-regulation the expression level of TLR4-MyD88-NF-κB pathway,improve the airway and pulmonary inflammatory conditions.Including the anti-inflammatory effect of high dose group is significantly lower than the middle and low dose group,which indicate that the anti-inflammatory effect is dose-dependent,and the higher dose of L.Pauciflorus smoke can bring better anti-inflammatory effect.