The Effects And Mechanism Of Total Sesquiterpenes From Tussilago Farfara L. On OVA-sensitized Asthma Model In Rats

Ethnopharmacology: Tussilago farfara L.is a dry flower bud of Farfarae Flos.It is mainly used to treat asthma and phlegm,persistent cough,acute and chronic tracheitis.The main components of Tussilago farfara L.are flavonoids,phenylpropanoids,sesquiterpenes,triterpenoids and alkaloids.It has anti-inflammatory,anti-oxidative and anti-allergic effects.We found that the water extract of Tussilago farfara L.has the effect of relieving cough and resolving phlegm,and the petroleum ether extract of Tussilago farfara L.has the activity of intervening allergic asthma.Previous studies have shown that total sesquiterpenes of Tussilago farfara L.have anti-inflammatory effects.On previous studies,this study will analyze the intervention effect of sesquiterpenes,a characteristic component of the petroleum ether fraction of Tussilago farfara L.,on OVA-sensitized allergic asthmatic rats,and analyze its intervention mechanism by metabolomics technology.Objects: To analyze the effects of total sesquiterpenes of Tussilago farfara L.on OVA-sensitized allergic asthmatic rats and its mechanism.Methods:(1)The preparation of total sesquiterpenoids from Tussilago farfara L.The total sesquiterpenoids from the petroleum ether fraction of Tussilago farfara L.were purified and enriched by medium-pressure method.The preparation methods of total sesquiterpenoids from Tussilago farfara L.were determined by investigating different types of FLASH columns.The total sesquiterpenoids from Tussilago farfara L.were qualitatively tested by NMR.The purity of total sesquiterpenes in Tussilago farfara L.was determined by HPLC.(2)The intervention effect of total sesquiterpenoids of Tussilago farfara L.on OVA-sensitized allergic asthmatic rats: In this study,OVA-sensitized allergic asthmatic rat models were used to characterize the intervention effect of total sesquiterpenoids of Tussilago farfara L.on OVA-sensitized allergic asthmatic rats by serum,biochemical indicators,lung and BALF.(3)The intervention mechanism of total sesquiterpenoids of Tussilago farfara L.on OVA-sensitized asthmatic rats: The expression of p65 NF-k B protein from lung tissue was analyzed by Western blot technique,and the intervention pathway of total sesquiterpenoids of Tussilago farfara L.on OVA-sensitized asthmatic rats was explored.Using UPLC/MS metabonomics technology to find pathways.Results:(1)The preparation of total sesquiterpenes from Tussilago farfara L..Angle C 18 FLASH column(20 g,20-35 um)with 85 % methanol as mobile phase was used to preparation under medium pressure for 35 minutes.The total sesquiterpenes of Tussilago farfara L.were obtained between 5-35 minutes.Among them,the purity of this one is about 10 times higher than that of petroleum ether fraction.Qualitative analysis of total sesquiterpenoids by NMR showed less fatty acid impurities,and the total sesquiterpenoids were enriched compared with petroleum ether.(2)The intervention effect of total sesquiterpenes of Tussilago farfara L.on OVA-sensitized allergic asthmatic rats.Total sesquiterpenoids of Tussilago farfara L.can reduce the infiltration of inflammatory cells in the lung,improve the growth and deformation of bronchi,effectively regulate the levels of inflammatory factors such as s OVA-Ig E,IL-4,IL-13 in serum,and alleviate asthma symptoms.(3)The intervention mechanism of total sesquiterpenoids of Tussilago farfara L..on OVA-sensitized allergic asthmatic rats.Total sesquiterpenoids of Tussilago farfara L.can affect the levels of endogenous metabolites such as arginine,arginine,phenylalanine,prostaglandin E1,prostaglandin E2,EPA,and interfere with four distinct alteration pathways such as arginine and proline metabolism pathway,which can regulate asthma in rats.And it can also down-regulate the expression of p65 NF-k B protein.Blocking the transmission of proinflammatory factors to intracellular signals,inhibiting the release of inflammatory factors,and alleviating inflammation.Conclusions: In this study,the preparation method of total sesquiterpenoids from Tussilago farfara L.was established by medium-pressure preparation,but the preparation process still needs to be further explored.The effect of total sesquiterpenoids of Tussilagofarfara L.on allergic asthma was verified by OVA sensitized asthmatic rat model.The total sesquiterpenes of Tussilago farfara L.can interfere with the metabolic balance of organism,inhibit the overexpression of p65 NF-k B protein,block the transmission of pro-inflammatory factors to intracellular signals,inhibit the release of inflammatory factors and alleviate inflammation.