Effect of Jiawei Taoren Chengqi Decoction on autophagy in rats with mechanical ventilation-induced lung injury / 天津医药

ABSTRACT

Objective To explore the impact of Jiawei Taoren Chengqi Decoction on autophagy in rats with mechanical ventilation-induced lung injury(VILI)through adenylate-activated protein kinase(AMPK)/mammalian target of rapamycin(mTOR)signaling pathway.Methods Sixty SPF male rats were randomly grouped into the sham operation group,the model group,the low-dose Jiawei Taoren Chengqi Decoction group(TCM-L group,2.85 g/kg),the high-dose Jiawei Taoren Chengqi Decoction group(TCM-H group,8.55 g/kg)and the high-dose Jiawei Taoren Chengqi Decoction + AMPK inhibitor Compound C group(TCM-H+CC group,Jiawei Taoren Chengqi Decoction 8.55 g/kg+ Compound C 250μg/kg),12 in each group.Oxygenation index(OI)was measured immediately after intubation and at 1 h,2 h and 4 h after mechanical ventilation.Bronchoalveolar lavage fluid(BALF)was collected after mechanical ventilation,levels of tumor necrosis factor(TNF)-α,interleukin(IL)-1β and IL-18 in BALF were detected by enzyme-linked immunosorbent assay(ELISA).Rats were sacrificed,and lung tissue was taken to measure the wet/dry weight(W/D)ratio.HE staining was used to observe pathological changes of lung tissue in each group of rats.Lung injury scores were carried out.Morphology of alveolar epithelial cells was observed by transmission electron microscopy.RT-qPCR was applied to detect mRNA expression levels of AMPK and mTORC1 in rat lung tissue.Western blot assay was applied to detect expression levels of AMPK,p-AMPK,mTORC1,p-mTORC1 and autophagy-related proteins in rat lung tissue.Results Compared with the sham group,the pathological damage of lung tissue was serious,lung W/D,levels of TNF-α,IL-1β and IL-18 in BALF,lung injury score,mTORC1 mRNA expression level,and p-mTORC1 protein expression were increased in the model group(P＜0.05).OI values at 2 h and 4 h of mechanical ventilation,AMPK mRNA expression level,p-AMPK,LC3-II/LC3-I and Beclin-1 protein expression in lung tissue were decreased(P＜0.05).Compared with the model group,the pathological damage of lung tissue was alleviated in the Chinese medicine-H group,and the trend of changes in related indexes was opposite to the above(P＜0.05).Autophagosomes in alveolar epithelial cells were increased.Compound C attenuated the protective effect of Jiawei Taoren Chengqi Decoction on VILI rats(P＜0.05).Conclusion Jiawei Taoren Chengqi Decoction may promote autophagy and reduce VILI in rats by activating AMPK/mTOR signaling pathway.