Effect Of Total Glycosides Of Qiwei Baizhusan On Intestinal Microecology In Mice With Dysbacteriosis And Diarrhe

Objective: To clarify the effects of total glycosides(TG)from Qiwei Baizhu Powder(QWBZP)on the intestinal microecology of diarrheal mice and the in vitro metabolism of total glycosides of Qiwei Baizhu Powder(QWBZP-TG)by the gut microbiota of mice.The results are helpful to explore the material basis and mechanism of QWBZP in the treatment of diarrhea from the perspective of intestinal microecology.Methods: Total glycosides were extracted from QWBZP decoction.The chemical compounds were detected by UHPLC-Q-TOF-MS/MS and were identified by the fragmentation ions information.Cefradine and gentamicin sulfate suspension were used to establish the dysbiosis-diarrhea mouse model.The feces in the colon of normal and diarrheal mice were collected and prepared for the gut microbiota incubation solution.Then QWBZP-TG were incubated with the gut microbiota of normal mice and diarrheal mice respectively.The metabolites were identified and the metabolic difference was compared between normal and diarrheal mice.Besides,QWBZP and QWBZP-TG were used to treat the mice with diarrhea.The effects of QWBZP-TG on the intestinal microecology of dysbiosis-diarrhea mice were evaluated by the results of in vitro microbial culture,microbial activity,digestive enzyme activity,inflammatory factors,bile acid metabolism,and 16 S r RNA gene sequencing and compared with the efficacy of QWBZP.Results:(1)A total of 68 compounds were identified in QWBZP-TG.Triterpenoid saponins and isoflavone glycosides were the dominant compounds.Moreover,phenylethanol glycosides,flavanones glycosides,chalcones glycosides,flavone glycosides,phenylethanoid glycosides,and aglycone were also detected.(2)A total of 7 new metabolites,including dihydrodaidzein,liquiritigenin,dehydroliquiritigenin,dihydroisoliquiritigenin,4’-dehydroxyliquiritigenin-7-methyl ether,zingibroside R1,and compound K were identi-fied.The metabolic pathway of QWBZP-TG was consistent between normal and diarrheal mice,but the GM of normal mice metabolized most of the glycosides in QWBZP-TG faster than that of diarrheal mice and dihydrodaidzein was specially produced.However,the dehydrogenation of diarrheal mice was more powerful than that of normal mice.(3)QWBZP-TG at each dose promoted the proliferation of Bifidobacterium,Lactobacillus,and Escherichia coli.Surprisingly,QWBZP-TG at the low dose,equivalent to the one used in humans,significantly promoted the proliferation of Bifidobacterium(P<0.01)and Lactobacillus(P<0.05).All doses of QWBZP-TG increased intestinal microbial activities(P<0.01),lactase activities(P<0.01),and sucrase activities(P<0.01 or P<0.05)in the mice with diarrhea.(4)The results of 16 S r RNA gene sequencing showed that mixed antibiotics decreased the relative abundance of Firmicutes while increased the relative abundance of Proteobacteria,and QWBZP-TG restored the two phyla to normal levels.At the genus level,the combination of antibiotics reduced the number of Lactobacillus and promoted the proliferation of Clostridium,while the QWBZP-TG promoted the proliferation of Lactobacillus and inhibited the growth of Clostridium.The combination of antibiotics increased the total bile acids in the colon of mice,and QWBZP decoction and QWBZP-TG reduced the content of total bile acids and primary bile acids in diarrheal mice.Meanwhile,it was found that the modulated effects of QWBZP-TG on the beneficial bacteria and bile acids were better than that of QWBZP decoction.(5)The changes of mucosa-associated microbiota in the diarrheal mice were consistent with those in the lumen-associated microbiota.However,QWBZP-TG decreased the relative abundance of Firmicutes significantly(P<0.01),while increased the relative abundance of Bacteroidetes and Tenericutes significantly(P<0.01).At the genus level,QWBZP decoction promoted the proliferation of Candidatus Arthromitus which was reduced by mixed antibiotics but did not return to the normal level.However,QWBZP-TG increased Prevotella obviously.The decoction and total glycosides of QWBZP reduced the content of IL-6(P<0.05),TNF-α,and s Ig A,while increased IL-10 significantly(P<0.05).Conclusion:(1)The gut microbiota was altered and the ability to metabolize glycosides was inhibited by mixed antibiotics.(2)QWBZP-TG promoted the proliferation of Lactobacillus and Bifidobacterium in vivo,which is consistent with QWBZP decoction,but the effects were more significant.(3)QWBZP-TG can regulate the metabolism of bile acids,repair the mucosal barrier and alleviate inflammatory reactions.Glycosides are the dominant components of QWBZP in diarrhea treatment.(4)Intestinal microecology can be used as an important index to evaluate the effecacy components of drugs.