Abstract:To observe the effects of Kuanxiong Lifei Decoction combined with Sanzi Yangqin Decoction on mitochondrial function and expression of nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3) in rats with chronic obstructive pulmonary disease(COPD) and to explore the efficacy and mechanism of Kuanxiong Lifei Decoction combined with Sanzi Yangqin Decoction in the treatment of COPD.Methods:COPD model rats were established by smoking cigarette and injection of endotoxin in trachea.Male Wister rats were randomly assigned into a normal control group(n=7),a COPD group(n=7),a low-dose group(n=7),a medium-dose group(n=7),a high-dose group(n=7),and a N-acetylcysteine(NAC) group(n=7).Western blotting was employed to determine the protein levels of NLRP3,apoptosis-associated speck-like protein(ASC),and caspase-1 in the lung tissue of rats.Enzyme-linked immunosorbent assay(ELISA) was employed to measure the levels of the downstream inflammatory cytokines interleukin-1β(IL-1β) and 1β-18(IL-18).MitoSOX red probe was used to detect the production of mitochondrial reactive oxygen species(ROS).ATP and JC-1 assay kits were used to respectively detect the ATP level and mitochondrial membrane potential in the lung tissue.Results:Compared with the control group,the modeling of COPD inhibited the synthesis of mitochondrial ATP(P<0.01),increased the production of ROS(P<0.01),and decreased the mitochondrial membrane potential(P>0.05).Compared with the model group,Kuanxiong Lifei Decoction combined with Sanzi Yangqin Decoction increased the synthesis of mitochondrial ATP and decreased the production of ROS in a dose-dependent manner(P<0.01),but had no significant effect on mitochondrial membrane potential.Similarly,the positive control drug NAC increased the synthesis of mitochondrial ATP and decreased the production of ROS(P<0.01).Western blot showed that the protein levels of NLRP3,ASC,and caspase1-p10 in COPD rats was significantly higher than those in the normal control group.NAC and Kuanxiong Lifei Decoction combined with Sanzi Yangqin Decoction down-regulated the expression levels of the above proteins.The results of ELISA showed that the modeling of COPD promoted the expression of IL-1β and IL-18 compared with the normal control group.After the intervention with NAC or different doses of Kuanxiong Lifei Decoction combined with Sanzi Yangqin Decoction,the levels of IL-1β and IL-18 protein in COPD rats decreased(P<0.05).Conclusion:Kuanxiong Lifei Decoction combined with Sanzi Yangqin Decoction can significantly alleviate the pathological changes of lung tissue in COPD rats,which may be related to the inhibition of NLRP3 signaling pathway induced by mitochondrial ROS release after mitochondrial damage.