Study On Metabonomics Mechanism Of Shegan Mahuang Decoction In Intervening Asthma Rats

Objective: Shegan mahuang decoction(SMD)is a traditional Chinese medicine,which has been used to treat asthma for thousands of years.Its clinical efficacy is remarkable.A metabolomics approach was used to investigate differential metabolites from plasma,urine and feces samples.Combined with the database,we constructed the differential metabolite-target-asthma network and the differential metabolite-signaling pathway-gene network for the treatment of asthma with Shegan Mahuang Decoction.Methods: 1.72 male SD rats were randomly divided into: normal control group(NC),OVA group(OVA),high-dose SMD treatment group(SMD-H),medium-dose SMD treatment group(SMD-M),low-dose SMD treatment group(SMD-L)and dexamethasone group(Dex).The levels of serum immunoglobulin(Ig E),C-reactive protein(CRP)and interleukin-4(IL-4)in allergic asthma rat model using ovalbumin were detected by enzyme-linked immunosorbent assay(ELISA).In order to evaluate the curative effect of the drug,the lung tissue was stained and airway scored.2.Liquid chromatography-mass spectrometry(LC-MS)-based technique for metabolomic analysis of plasma,urine and feces samples.Partial least squares discriminant analysis(PLS-DA)was used to identify patterns.Differential metabolites were screened by variable importance in the Variable importance in the projection(VIP value),fold change(FC)and P-value.Differential metabolites were identified by accurate molecular weight and secondary fragmentation in the Human Metabolome Database(HMDB),followed by pathway enrichment for differential metabolites.3.Screening the potential targets of different metabolites in asthma by network pharmacology.Differential metabolites combined with Gene Expression Omnibus(GEO)database were used to explore the potential signal pathway of SMD regulation and explore the mechanism of SMD in treating asthma.The key differential metabolite leukotriene B4(LTB4)was verified by ELISA.Results: 1.Administration of SMD attenuated the histopathological changes in the lungs associated with the model,improved the lung tissue status and reduced the airway scores.2.From the metabolomic analysis,a total of 28 differential metabolites were identified in plasma,of which 24 were reversed regulated by SMD treatment and were involved in several metabolic pathways such as sphingolipid metabolism and arachidonic acid metabolism.A total of 29 differential metabolites were identified in urine,21 of which were reversed by SMD and involved in tyrosine,taurine and hypotaurine metabolism.A total of45 differential metabolites were identified in faeces,31 of which were reversed by SMD.These were involved in histidine metabolism,linoleic acid metabolism,etc.3.48 potential targets of SMD for asthma such as Ednra,Pparg,Ptger2,Trpv1 and Mme were screened by network pharmacology analysis.In combination with the GEO database,nine pathways were enriched,such as the oxidase proliferator-activated receptor(PPAR)pathway.The important differential metabolite LTB4 was significantly decreased after SMD treatment.Conclusion: SMD is effective in the treatment of asthma,through affecting the differential metabolism of LTB4 and histamine,the regulation of Ednra,Pparg and other potential targets,and regulating the comprehensive regulation of sphingolipid metabolism,arachidonic acid metabolism,peroxisome proliferator-activated receptor(PPAR)signaling pathway,etc.,to produce anti-asthma effect on ovalbumin-induced asthma effect,reflecting the multi-target and multi-pathway of TCM.The synergistic effect of TCM with multiple multiple targets and multiple pathways in the treatment of asthma was demonstrated.This study expands our understanding of SMD for asthma treatment from a metabolomics perspective.