新外来中药紫锥菊清泻肺热治疗急性肺炎及其机制研究OA北大核心CHSSCDCSTPCD

Objective:To investigate the therapeutic effects of new exotic herbal medicine Echinacea purpurea on clearing lung heat and its properties in acting on the lung meridian.Methods:Fifty-six Wistar rats were randomly divided into a blank group,model group,dexamethasone group,low-dose ethanol extract of E.purpurea group,high-dose ethanol extract of E.purpurea group,low-dose water extract of E.purpurea group,and high-dose water extract of E.purpurea group,with 8 rats per group.Except for the blank group,all other groups were administered corresponding drugs orally for 14 days,and on the final day,an acute pneumonia model was prepared by aerosol inhalation of lipopolysaccharide.Lung wet/dry weight ratio,total white blood cell(WBC)count in bron-choalveolar lavage fluid,percentage of inflammatory cells in peripheral blood,serum levels of inflammatory mediators,cyclic adeno-sine monophosphate(cAMP),oxidative stress levels,pathological changes in lung tissues,and mRNA expression levels of Toll-like receptor 4(TLR4),nuclear factor kappa B(NF-κB),heme oxygenase-1(HO-1),and nuclear factor erythroid 2-related factor 2(Nrf2)in the right lower lung tissue of rats were assessed.Results:Compared with the rats in the model group,those treated with ethanol extract of E.purpurea showed reduced lung pathology,significantly decreased lung wet/dry weight ratio(P＜0.05),and sig-nificant reductions in WBC counts in bronchoalveolar lavage fluid and peripheral blood(P＜0.05).Levels of pro-inflammatory cy-tokines tumor necrosis factor-alpha(TNF-α),interleukin-1 beta(IL-1β),IL-6 were significantly reduced(P＜0.05),while anti-in-flammatory cytokine IL-10 was significantly increased(P＜0.05).Malondialdehyde(MDA)content was significantly reduced(P＜0.05),and glutathione peroxidase(GSH-Px)was significantly increased(P＜0.05).Moreover,cAMP levels were significantly de-creased(P＜0.05),and mRNA expression levels of NF-κB,HO-1,and Nrf2 were significantly decreased(P＜0.05),with no sta-tistical significance observed in TLR4 mRNA expression.Rats treated with high-dose water extract of E.purpurea exhibited mild congestion and dilation of pulmonary capillaries,reduced infiltration of inflammatory cells,and less thickening of alveolar septa.Lung wet/dry weight ratio was significantly decreased(P＜0.05),peripheral blood WBC was significantly decreased(P＜0.05),and levels of TNF-α,IL-1 β,IL-6 were significantly reduced(P＜0.05).IL-10 was significantly increased(P＜0.05),MDA con-tent was significantly decreased(P＜0.05),and GSH-Px was significantly increased(P＜0.05).Furthermore,c AMP levels were significantly decreased(P＜0.05),and mRNA expression levels of NF-κB,HO-1,and Nrf2 were significantly decreased(P＜0.05),with no statistical significance observed in TLR4 mRNA expression.Conclusion:E.purpurea has a preventive effect on a-cute pneumonia,which may be related to its inhibition of TNF-a,IL-1β,IL-6 levels and modulation of NF-κB,HO-1,and Nrf2 mR-NA expression levels.From the perspective of traditional Chinese medicine theory,this action correlates with the properties of E.purpurea in acting on the lung meridian and clearing lung heat.