Study On The Mechanism Of Action And Active Ingredients Of Expectorant In Tussilago Farfara Based On Gut Metabolome

Topic basis: Modern research and epidemiology prove a close association between the gut microbiota and the lungs,called the "gut-lung axis." Based on the theory of " gutlung axis ",there has been research on " lung disease and bowel treatment ",and the effect of changing the structure of intestinal flora through fecal microbiota transplantation(FMT)technology to achieve the treatment of respiratory diseases has been used for the treatment of COPD,lung injury and other diseases.Studies have reported that the regulation of gut microbiota structure and microbiota metabolites by traditional Chinese medicine or traditional Chinese medicine components is an important way to treat diseases.Tussilago farfara L.,a dried bud of the Asteraceae plant,has cough,expectorant and asthmatic effects,and the correlation between expectorant effect and gut microbiota is unclear.Objective: This study intends to elucidate the mechanism of action and active ingredients of expectorant based on the gut microbiota.Methods:1.Establish a mixed antibiotic flora disorder model and observe the change of expectorant effect of Tussilago farfara L.(FF);The analysis of intestinal metabolites associated with expectorant effect of winter flowers was analyzed by LC-MS technology.2.Use fecal microbiota transplantation experiment to verify whether the expectorant effect of FF depends on intestinal flora;LC-MS technology was used to detect changes in microbiota metabolites associated with expectorant effect of FF.3.Supplementary verification experiments were carried out based on metabolites(dihydrocaffeic acid,quinic acid,caffeic acid)and key metabolites(arginine)screened by microbiota metabolomics.Changes in endogenous metabolites after supplementation with dihydrocaffeic acid,quinic acid,and arginine were analyzed by gut metabolomics and lung tissue metabolomics.Results:1.After the administration of FF,it can significantly increase phenolic red output and exert expectorant effect,and the expectorant effect of FF is weakened after mixed antibiotic pretreatment,suggesting that the expectorant effect of FF depends on gut microbiota;Based on LC-MS technology,28 differential intestinal metabolites that may be involved in the expectorant effect of FF were screened.2.Compared with the blank fecal microbiota transplantation solution(CFMT),FFMT can significantly increase phenol red output,and 16 key differential metabolites related to expectorant effect of FF were further identified based on LC-MS technology.Heatsterilized microbiota transplantation solution also has expectorant effect,indicating that in addition to viable microbiota,chemicals in the microbiota transplantation solution may also play an expectorant effect.3.Supplementary verification experiments were carried out on dihydrocaffeic acid,quinic acid and caffeic acid,metabolites of caffeoylquinic acid detected in the fecal microbiota transplantation solution,and the results showed that dihydrocaffeic acid and quinic acid had expectorant effects;gut metabolomic analysis of dihydrocaffeic acid and quinic acid can also affect arginine metabolism.Arginine supplementation experiments have demonstrated that arginine has a significant expectorant effect,and the mechanism may be expectorant effect achieved by increasing the abundance of active phospholipids in the lungs.Conclusion: The study found that the expectorant mechanism of FF depended on the gut microbiota.DCA and QA are the key compounds of expectorant effect;The arginine biosynthesis pathway is an important mechanism for expectorant effect.