The Screening Of Active Ingredients And The Underlying Mechanism In Psoraleae Fructus Treatment Of Ulcerative Colitis

Ulcerative colitis(UC)is an idiopathic long-term recurrent inflammatory disorder characterized by diarrhea and rectal bleeding.The inflammation generally starts from the rectum in relation to colon mucosa and submucosa,and then spreads throughout the colon over time.It has been listed as one of the most formidable diseases by the World Health Organization because of its etiological complexity,onset variability,curable difficulty,high recurrence rate,poor prognosis and increased risk of colon cancer.Psoraleae Fructus(PF)and preparations containing PF are commonly used in Traditional Chinese Medicine to treat chronic ulcerative colitis typed with both spleen and kidney deficiency and achieved good curative effect.However,the material basis and mechanism of action remain unclear.Various chemical ingredients have been isolated from PF,mainly including coumarins,flavonoids.chalcones and meroterpenes,etc,which have showed extensive pharmacological activities such as anti-inflammatory,antibacterial,antioxidant,anti-tumor,antidepressant,estrogenic activity,estrogenic activity,and neuroprotection,etcIn this paper,a PF fingerprint research method was established and the quantify of 12 compounds(including psoralen,isopsoralen,isobavachin.neobavaisoflavone.bavachin,ostruthin,corylin,psoralidin,4,5-dehydroisopsoralidin,isobavachalcone.isobavachromene,and bakuchiol)in 29 batches from 10 places of origin were determined.Top four ingredients bakuchiol,psoralen,isopsoralen,and isobavachalcone in PF were foundBased on the PF fingerprint,an UHPLC-MS/MS method was developed and validated for simultaneous quantification of 13 compounds(including psoralen,isopsoralen,isobavachin,bakuchalcone.neobabaisoflavone,bavachin,corvlin,psoralidin,isobavachalcone,bavachinin.corylifol A,bavachalcone and bakuchiol)of PF in rat plasma.The method was successfully applied to the pharmacokinetic study of oral administration of PF in rats.The results showed that the three highest exposure compounds in rat plasma were psoralen,isopsoralen,and bakuchiol.Although bakuchiol was the highest ingredients in PF,the exposure of bakuchiol in plasma was lower than that of psoralen and isopsoralen.We compared the pharmacokinetic parameters between male and female rats and found that the AUCO-t and Cmax of psoralen,isopsoralen,isobavachin,bavachin,psoralidin,isobavachalcone and bavachinin in female rats were significantly lower than in male rats.The pharmacokinetic study provided certain research foundation and basis for the screening of the effective ingredients of PF for UC in vivoCombine with the research result of PF fingerprint and the pharmacokinetic study in rats,we chose aqueous extraction of PF,and 3 highest exposure compounds of PF(psoralen,isopsoralen,and bakuchiol)in rats as the efficacy-related potential active ingredients in dextran sulfate sodium(DSS)-induced UC model in mice.The results showed that aqueous extraction of PF and psoralen significantly attenuated the severity of DSS-induced UC in mice,including the decreased body weight and shorten colorectal.The diarrhea and hematochezia of mice were delayed and alleviated,the mortality rate and serum cytokine were decreased,and the crypt atrophy and inflammatory cell infiltration caused by DSS were significantly reduced.Moreover,the levels of bile acids in serum elevated while the bile acids in feces decreased.These results implicated the effects of aqueous extraction of PF and psoralen in the treatment of DSS-induced UC which might be associated with the homeostasis maintains of bile acids in miceIn our study,we found that psoralen treatment exhibited significant therapeutic effects on DSS-induced UC in mice,which markedly alleviate body weight loss,Disease Activity Index(DAI)scores,and histological scores of UC induced by DSS.We also found that psoralen treatment significantly reduced the levels of IL-1β,IL-6,and TNF-α in serum and suppressed the over-expressions of IL-1β,IL-6,and TNF-α mRNA in colon induced by DSS.Psoralen treatment increased the mRNA transcription of ileum Fxr,Shp,and Fgf15,as well as the expression of FXR and FGF15 in UC model.Psoralen treatment markedly increased the mRNA transcription of Asbt,Ostα/β,and I-Babp in ileum while decreased hepatic CYP7A1 mRNA and protein expression.These findings suggested the promoted ileal bile acids absorption by the up-regulated expression of ASBT on epithelial cells in ileum under Psoralen treatment.Then the bile acids can be transported to the basolateral membrane after bond with the I-Babp,and through the transporter Ostα/β into blood,finally circulate to the liver via the portal vein.Psoralen reduced the synthesis of bile acid in the liver and the accumulation of bile acids in colon,so as to improve the impairment of high concentration of bile acids to colonIn summary,we demonstrated that PF and its active ingredient psoralen treatment mitigate DSS-induced UC in mice,the underlying mechanism might be associated with the homeostasis of bile acids regulated by FXR-FGF15 pathways.This study has provided the certain nonclinical evidence in early stage of PF research,and the active ingredient psoralen may be a potential drug candidate for UC treatment.