Studies On The Chemical Components Of Schisandrae Chinensis Fructus In Alleviating Nonalcoholic Fatty Liver Disease

With the improvement of living standards and changement of lifestyle,the incidence of non-alcoholic fatty liver disease(NAFLD)is rapidly increasing,and the patient is gradually becoming younger,which has become one of the global public health problems.However,its etiology is complex,at present there is no targeted therapeutic drug.Therefore,screening efficient and safe therapeutic drugs is of great significance for the prevention and treatment of NAFLD.Natural products derived from traditional Chinese medicine is an important source of innovative drug discovery.Schisandrae Chinensis Fructus is the dried ripe fruit of Schisandra chinensis(Turcz.)Baill.,which belongs to genus Schisandra of the Schisandraceae.It has the effects of protecting the liver,delaying aging,and nourishing qi and promoting fluid production.It is used as a combination of medicinal herbs in various traditional Chinese medicine preparations for protecting the liver,such as Fuzheng Huayu Capsules,Hugan Granules,and Hugan Capsules.In addition,two liver protective drugs,bicyclol and biphenyl diester,have been developed based on its main component schisandrin C,which have significant effects in treating drug-induced liver injury and viral hepatitis.A large number of literature reports and previous research by the research team have shown that Schisandrae Chinensis Fructus also has wide application prospects in the prevention and treatment of NAFLD.Its alcohol extract can effectively alleviate the effect of NAFLD,and the active fraction is mainly concentrated in the petroleum ether fraction.However,current research mainly focuses on extractive and a few compounds such as schisandrin A,schisandrin B,and basic research is relatively weak.In order to further explore the active components of Schisandrae Chinensis Fructus in alleviating NAFLD,according to the preliminary research of the research group,Firstly,based on an in vitro cell model,the active components of the petroleum ether fraction were screened;Secondly,modern chromatographic separation methods are used to separate the chemical components of its active fraction and comprehensively characterize their chemical composition;Finally,based on network pharmacology and molecular docking technology,the active ingredients and potential mechanisms of Schisandrae Chinensis Fructus in alleviating NAFLD were studied.The specific results are as follows:1.This study used 95%,85%,and 65%ethanol to extract the fruit of Schisandrae Chinensis Fructus,and obtained the ethanol extract of Schisandrae Chinensis Fructus.Using petroleum ether extraction to obtain the active fraction screened in the early stagepetroleum ether site,the petroleum ether fraction was separated into four components with different polarities(PET1-PET4)through silica gel column chromatography.The HepG2 cell model induced by sodium oleate and sodium palmitate was used to screen the anti NAFLD activity of PET1-PET4.The oil red O staining results showed that the 25 μg/mL PET1,PET2,and PET4 fraction had no significant lipid-lowering effect,while the PET3 fraction could significantly reduce intracellular lipid accumulation.In addition,PET3 treatment significantly reduced the levels of TG and TC in HepG2 cells,indicating that the active component of Schisandrae Chinensis Fructus in alleviating NAFLD is PET3.Therefore,the chemical composition of PET3 fraction will be studied in the future.2.In order to explore the active ingredients of Schisandrae Chinensis Fructus to alleviate NAFLD,30 compounds were isolated from the PET3 fraction of Schisandrae Chinensis Fructus by various chromatographic separation technologies and solvent methods.The known compounds were identified by mass spectrometry and nuclear magnetic resonance technology,including twenty-five biphenylcyclooctene lignans(1-25),two diarylbutane lignans(26-27),two tetrahydrofuran lignans(28-29),and one sesquiterpene compound(30),among them there is one compound first discovered from Schisandrae Chinensis Fructus,sieverligan E(25).In addition,two new compounds have been discovered:(R)-1,2,3,10,11,12-hexamethoxy-6-methyl-7-methylene-5,6,7,8-tetrahydrodibenzo[a,c][8]annulen-6-ol(1)and(S)-1,2,3,10,11,12-hexamethoxy-6-methyl-7-methylene-5,6,7,8-tetrahydrodibenzo[a,c][8]annulen-6-ol(2).In addition,the hydrogen and carbon spectrum characteristics of biphenylcyclooctene lignans were summarized based on the identified compounds,including the chemical shift patterns of aromatic protons C4 and C-11,aromatic quaternary carbon,methoxy group,methyl,C-6 and C-9 positions on the eight membered ring,as well as C-7 and C-8 positions.Based on the compounds isolated from Schisandrae Chinensis Fructus,the typical cleavage pathways of biphenylcyclooctene lignans were summarized.And based on the 30 compounds obtained from the above separation and the local database constructed by Proggenesis SDF Studio,UPLC-Q-TOF-MS/MS technology was used to further comprehensively characterize the active fraction PET3.A total of fifty-six compounds were identified,including forty-seven lignans,three triterpenes,one sesquiterpene,one flavonoid,one flavonoid and three alkaloids.3.Based on the previous chemical component analysis,the potential mechanism of PET3 fraction in alleviating NAFLD was explored using network pharmacology.Using SwissADME tool,30 active compounds were screened from 56 identified compounds of PET3 fraction according to the five principles of drug-like drugs.The targets of active compounds were intersected with disease targets,and a total of 161 intersection targets were found.Among them,targets HSP90AA1,MAPK3,SRC,MAPK1 and AKT1 may play an important role in the treatment of NAFLD.GO function and KEGG enrichment analysis showed that the PET3 fraction may alleviate NAFLD by participating in peptidyl serine modification,cell membrane raft composition,protein serine/threonine kinase activity binding,and regulating PI3K-Akt signaling pathway,insulin signaling pathway,insulin resistance and other pathways.Molecular docking showed that the RMSD value was stable,indicating that the interaction was stable and the results were reliable.The binding scores of most compounds to the targets were negative,indicating that the compounds and targets had a good connection,which further confirmed that these compounds may be active ingredients for alleviating NAFLD.The results of this study provide new ideas for the discovery of active compounds for the treatment of NAFLD,and provide a scientific basis for subsequent experimental research.In summary,this study focuses on the network pharmacology screening and molecular docking studies of the active parts of Schisandrae Chinensis Fructus in alleviating NAFLD,in order to study the pharmacodynamic material basis and mechanism of Schisandrae Chinensis Fructus in alleviating NAFLD from multiple perspectives and levels,so as to scientifically explain the traditional efficacy of Schisandrae Chinensis Fructus,explore the new functions of Schisandrae Chinensis Fructus,and provide scientific data support for the development,utilization and innovative development of Schisandrae Chinensis Fructus resources.