Objective To investigate the underlying mechanism of Hongyu Decoction in the treatment of inflammatory bowel disease(IBD)based on serum amino acid metabolism.Methods A total of 50 male C57BL/6J mice were divided into control group,model group,sulfasalazine(SASP)group and Hongyu Decoction low-and high-dosage groups,with 10 mice in each group.Except for the control group,the rest groups were treated with 3%dextran sulfate sodium freely for seven consecutive days to establish the IBD model.The SASP group was given SASP solution at a dosage of 200 mg/kg by gavage,while the Hongyu Decoction low-and high-dosage groups were given Hongyu Decoction freeze-dried powder solution at dosages of 0.5 and 2.0 g/kg respectively by gavage for 11 consecutive days.The general condition was monitored and DAI score were calculated.After the mice were sacrificed,the length of colons was measured,ELISA was used to detect serum TNF-α,IL-1β,IL-17 contents,HE staining was used to observe the morphology of colon tissue,and Alizarin blue staining was used to evaluate the secretion of mucin levels by intestinal epithelial goblet cells,UPLC-MS and multivariate statistical methods were used to analyze the serum amino acid metabolism profiles of mice in the control group,model group and Hongyu Decoction high-dosage group,and differential amino acids were screened.Pathway enrichment analysis was performed on differential amino acids using MetaboAnalyst 5.0.Results Compared with the control group,the DAI score of the model group mice significantly increased(P<0.001),the colon length was significantly shortened(P<0.001),and the serum contents of TNF-α,IL-1β and IL-17 significantly increased(P<0.001);with widespread ulceration of colon tissue,disappearance of mucosal epithelium and intestinal crypt structure,infiltration of lymphocytes and neutrophils,congestion and edema of intestinal mucosa,proliferation of submucosal connective tissue,reduced number of colonic goblet cells and mucin secretion.Compared with the model group,the Hongyu Decoction high-dosage group showed a significant decrease in DAI score(P<0.001),while the SASP group and the Hongyu Decoction low-and high-dosage groups showed a significant increase in colon length(P<0.05,P<0.001),and the serum contents of TNF-α,IL-1β and IL-17 were significantly reduced(P<0.001);the colonic villi were relatively intact,the glands were clear and arranged neatly,the branches of the intestinal crypts were obvious,no obvious edema was observed,and the number of colonic goblet cells and mucin secretion increased.Seven potential biomarkers for IBD in mice were identified through serum metabolomics screening,including tryptophan,serine,glutamate,valine,histidine,methionine and phenylalanine;two potential biomarkers for the treatment of IBD with Hongyu Decoction were identified,namely valine and tyrosine.The results of pathway enrichment analysis showed that the differential amino acids in the model group mainly involved the biosynthesis of phenylalanine,tyrosine and tryptophan,histidine metabolism,cysteine and methionine metabolism,phenylalanine metabolism and arginine biosynthesis;the differential amino acids in Hongyu Decoction high-dosage group mainly involved the biosynthesis of phenylalanine,tyrosine and tryptophan,as well as the metabolism of alanine,aspartate and glutamate,and the biosynthesis of arginine.Conclusion Hongyu Decoction can improve intestinal epithelial damage and inflammatory cell infiltration in IBD mice,protect the integrity of the intestinal mucosal barrier,and may be related to regulating amino acid metabolism in the body.

Objective To investigate the underlying mechanism of Hongyu Decoction in the treatment of inflammatory bowel disease(IBD)based on serum amino acid metabolism.Methods A total of 50 male C57BL/6J mice were divided into control group,model group,sulfasalazine(SASP)group and Hongyu Decoction low-and high-dosage groups,with 10 mice in each group.Except for the control group,the rest groups were treated with 3%dextran sulfate sodium freely for seven consecutive days to establish the IBD model.The SASP group was given SASP solution at a dosage of 200 mg/kg by gavage,while the Hongyu Decoction low-and high-dosage groups were given Hongyu Decoction freeze-dried powder solution at dosages of 0.5 and 2.0 g/kg respectively by gavage for 11 consecutive days.The general condition was monitored and DAI score were calculated.After the mice were sacrificed,the length of colons was measured,ELISA was used to detect serum TNF-α,IL-1β,IL-17 contents,HE staining was used to observe the morphology of colon tissue,and Alizarin blue staining was used to evaluate the secretion of mucin levels by intestinal epithelial goblet cells,UPLC-MS and multivariate statistical methods were used to analyze the serum amino acid metabolism profiles of mice in the control group,model group and Hongyu Decoction high-dosage group,and differential amino acids were screened.Pathway enrichment analysis was performed on differential amino acids using MetaboAnalyst 5.0.Results Compared with the control group,the DAI score of the model group mice significantly increased(P<0.001),the colon length was significantly shortened(P<0.001),and the serum contents of TNF-α,IL-1β and IL-17 significantly increased(P<0.001);with widespread ulceration of colon tissue,disappearance of mucosal epithelium and intestinal crypt structure,infiltration of lymphocytes and neutrophils,congestion and edema of intestinal mucosa,proliferation of submucosal connective tissue,reduced number of colonic goblet cells and mucin secretion.Compared with the model group,the Hongyu Decoction high-dosage group showed a significant decrease in DAI score(P<0.001),while the SASP group and the Hongyu Decoction low-and high-dosage groups showed a significant increase in colon length(P<0.05,P<0.001),and the serum contents of TNF-α,IL-1β and IL-17 were significantly reduced(P<0.001);the colonic villi were relatively intact,the glands were clear and arranged neatly,the branches of the intestinal crypts were obvious,no obvious edema was observed,and the number of colonic goblet cells and mucin secretion increased.Seven potential biomarkers for IBD in mice were identified through serum metabolomics screening,including tryptophan,serine,glutamate,valine,histidine,methionine and phenylalanine;two potential biomarkers for the treatment of IBD with Hongyu Decoction were identified,namely valine and tyrosine.The results of pathway enrichment analysis showed that the differential amino acids in the model group mainly involved the biosynthesis of phenylalanine,tyrosine and tryptophan,histidine metabolism,cysteine and methionine metabolism,phenylalanine metabolism and arginine biosynthesis;the differential amino acids in Hongyu Decoction high-dosage group mainly involved the biosynthesis of phenylalanine,tyrosine and tryptophan,as well as the metabolism of alanine,aspartate and glutamate,and the biosynthesis of arginine.Conclusion Hongyu Decoction can improve intestinal epithelial damage and inflammatory cell infiltration in IBD mice,protect the integrity of the intestinal mucosal barrier,and may be related to regulating amino acid metabolism in the body.

Background:Previous studies have proved that neutrophil gelatinase-associated lipocalin(NGAL)plays an important role in the progression of Crohn's disease(CD),and may serve as a potential biomarker for disease activity prediction,severity assessment,treatment response evaluation and prognosis monitoring.However,the diagnostic value of NGAL in perianal fistulizing Crohn's disease(pfCD)is still unclear.Aims:To investigate the serum level of NGAL and its diagnostic value in patients with active pfCD.Methods:A total of 66 patients diagnosed as pfCD from July 2021 to June 2023 at Longhua Hospital,Shanghai University of Traditional Chinese Medicine were enrolled,including 36 active pfCD patients and 30 inactive pfCD patients.The disease activity and perianal fistula activity were assessed by Crohn's disease activity index(CDAI)and perianal disease activity index(PDAI),respectively.Serum NGAL,fecal calprotectin(FC),C-reactive protein(CRP),erythrocyte sedimentation rate(ESR),as well as CDAI score and PDAI score were compared between the active and inactive pfCD patients,and the correlations of NGAL with the other parameters in active pfCD patients were analyzed.ROC curve was drawn to evaluate the values of serum NGAL,FC,CRP and ESR for diagnosis of active pfCD.Results:The serum NGAL,FC,CRP,ESR,CDAI score and PDAI score in active pfCD patients were significantly higher than those in inactive pfCD patients(all P＜0.001).NGAL was positively correlated with FC(r=0.64,P＜0.001),CRP(r=0.55,P＜0.001),ESR(r=0.53,P＜0.001),CDAI score(r=0.59,P＜0.001)and PDAI score(r=0.54,P＜0.001)in active pfCD patients.The optimal cut-off values of NGAL,FC,CRP and ESR were 220.5 μg/L,146.0 μg/g,7.9 mg/L and 23.5 mm/h,respectively,for the diagnosis of active pfCD,and the area under the curve were 0.922(95％CI:0.850-0.995),0.888(95％CI:0.806-0.970),0.853(95％CI:0.763-0.944)and 0.830(95％CI:0.731-0.930),respectively.Conclusions:Serum NGAL level is associated with the disease activity of pfCD,and can be used as a non-invasive biomarker for the clinical diagnosis of active pfCD.