小儿清感方调控Nrf2/HO-1/NQO1/ROS通路干预流感幼龄大鼠氧化应激损伤的作用机制OA

Objective:The action mechanism of Xiao'er Qinggan(小儿清感)prescription in intervening oxidative stress injury and inflammatory factors in lung tissues of young rats with influenza was explored through the nuclear factor erythroid 2-related factor 2(Nrf2)/hemoglobin oxygenase-1(HO-1)/NAD(P)H:quinine oxidoreductase 1(NQO1)/reactive oxygen species(ROS)pathway.Methods:Sixty male Sprague Dawley(SD)young rats were randomly divided into the normal group,model group,0.02 g/kg oseltamivir group,and Xiao'er Qinggan prescription(4.79,9.58,and 19.16 g/kg)groups,with 10 rats in each group.Except for the normal group,all other groups were intranasally inocula-ted with 100 μL of influenza virus once daily for 3 consecutive days to establish the influenza model in young rats.After successful modeling,the drug was administered once daily for 7 days.After 7 days,body weight and total lung weight were measured to calculate the lung index.Hematoxylin-eosin(HE)staining was used to observe the pathological chan-ges in lung tissue.Enzyme-linked immunosorbent assay(ELISA)was performed to determine the content of interleukin-Iβ(IL-Iβ),interleukin-6(IL-6),and tumor necrosis factor alpha(TNF-α)in serum.Reverse transcription polymerase chain reaction(RT-qPCR)was used to detect the relative expression of viral load in lung tissue.Fluorescence intensity of reactive oxygen species(ROS)in lung tissue was observed by confocal microscopy.The biochemical kit was used to detect the levels of oxidative stress indicators,including glutathione(GSH),malondialdehyde(MDA)level,and super-oxide dismutase(SOD)activity.Western and RT-qPCR blot were used to detect the relative expression levels of protein and mRNA of oxidative stress pathway-related proteins Nrf2,Kelch-like ECH-associated protein 1(Keap1),HO-1,and NQO1,respectively.Results:Compared with those in the normal group,the body weight,SOD activity,and GSH content of young rats in the model group decreased.The lung index,Smith's lung histopathological damage score,the levels of inflammatory factors IL-6,IL-1β,TNF-α,and MDA,and the ROS level increased.The relative expression levels of viral load in lung and Keap1 protein and mRNA were increased,while the relative expression levels of Nrf2,HO-1,and NQO1 protein and mRNA were reduced(P<0.05 or P<0.01).The model group showed severe pulmonary congestion and ede-ma,alveolar wall thickening,alveolar structural damage,and inflammatory cell infiltration in young rats.Compared with the model group,the 4.79,9.58,and 19.16 g/kg groups of Xiao'er Qinggan prescription and the 0.02 g/kg oseltamivir group could effectively increase the body weight,SOD activity,and GSH content.The relative protein and mRNA expres-sion levels of Nrf2,HO-1,and NQO1 were decreased(P<0.05 or P<0.01).The lung index,Smith's lung histopatho-logical damage score,the content of IL-6,IL-1β,TNF-α,MDA,and ROS level decreased.The relative expression of viral load and the relative expression of Keap1 protein and mRNA were decreased(P<0.05 or P<0.01),while the lung tissue damage and inflammatory infiltration were significantly improved.Conclusion:Xiao'er Qinggan prescription can effec-tively mitigate the degree of pulmonary edema and inflammatory injury caused by the influenza virus,and its mechanism may be related to regulating the Nrf2/HO-1/NQO1/ROS signaling pathway and exerting anti-influenza effects to inhibit the oxidative stress process.