黄芪甲苷通过LC3/Beclin 1干预哮喘寒饮蕴肺证大鼠细胞自噬的机制

Mechanism of astragaloside regulating airway inflammation through LC3/Beclin 1 in rats of bronchial asthma with syndrome of cold retention accumulation in lung

目的:探讨黄芪甲苷干预哮喘寒饮蕴肺证大鼠细胞自噬的机制。方法:SPF级Wistar雄性大鼠40只随机分为空白组、模型组、黄芪甲苷组、雷帕霉素组,每组10只,建立哮喘寒饮蕴肺证大鼠模型,相应组给予黄芪甲苷10 mg·kg^(-1)·d^(-1)、雷帕霉素0.01 mg·kg^(-1)·d^(-1)治疗。观察大鼠体质量变化,检测大鼠支气管肺泡灌洗液(B A L F)中炎症因子[白介素(I L)-4、I L-13],观察大鼠肺组织病理、肺组织自噬小体、肠组织变化。RT-PCR、Western blot检测大鼠自噬基因(Beclin 1、LC3、mTOR mRNA)及蛋白水平(LC3Ⅱ/Ⅰ、Beclin 1、mTOR)。结果:与空白组比较,模型组大鼠肺组织及气道组织出现炎性浸润、出血、细胞脱落等情况,BALF中IL-4、IL-13表达水平显著上升(P<0.01),肺组织自噬基因LC3、Beclin 1 mRNA表达显著降低(P<0.01),肺组织自噬蛋白LC3Ⅱ/Ⅰ、Beclin 1相对表达显著下降(P<0.05);mTOR mRNA及蛋白相对表达显著升高(P<0.01)。给药组治疗后,各指标均出现不同程度的改善,黄芪甲苷组效果最佳。结论:黄芪甲苷通过提高哮喘寒饮蕴肺证大鼠细胞自噬能力以清除气道内坏死异物,减轻气道炎症反应,增强机体的气化作用,以缓解气道炎症。

Objective:To explore the mechanism of astragaloside intervention in the autophagy of asthma models with cold retention accumulation in lung.Methods:Forty SPF-grade male Wistar rats were randomly divided into a control group,model group,astragaloside group,and rapamycin group,with 10 rats in each group.An asthma model with cold rheum accumulating in lung was established,and corresponding treatments were administered:astragaloside(10 mg·kg^(-1)·d^(-1))and rapamycin(0.01 mg·kg^(-1)·d^(-1)).Changes in body weight were observed,and inflammatory factors[interleukin(IL)-4,IL-13]in bronchoalveolar lavage fluid(BALF)were measured.Pathological changes in lung tissue,autophagic bodies in lung tissue,and intestinal tissue changes were examined.PCR and Western blot analyses were conducted to detect the levels of autophagy genes(Beclin1,LC3,mTOR mRNA)and proteins(LC3 II/I,Beclin1,mTOR).Results:Compared to the control group,the model group showed inflammatory infiltration,hemorrhage,and cell shedding in lung and airway tissues.The expression levels of interleukins(IL)-4 and IL-13 in BALF significantly increased(P<0.01),while the mRNA expressions of autophagy genes LC3 and Beclin 1 in lung tissue significantly decreased(P<0.01).The relative expression of autophagy proteins LC3 II/I and Beclin 1 also significantly declined(P<0.05),while mTOR mRNA and protein levels significantly increased(P<0.01).In the treatment groups,administration of astragaloside and rapamycin led to varying degrees of improvement in all indicators,with the astragaloside group showing the best effects.Conclusion:Astragaloside enhances autophagy in rats with asthma due to cold rheum accumulating in lung,facilitating the clearance of necrotic foreign substances in the airways,reducing airway inflammatory responses,and improving the body’s ability to regulate gas exchange,thus alleviating airway inflammation.