Altered profiles of fecal bile acids correlate with gut microbiota and inflammatory responses in patients with ulcerative colitis

BACKGROUND Gut microbiota and its metabolites may be involved in the pathogenesis of inflammatory bowel disease.Several clinical studies have recently shown that patients with ulcerative colitis(UC)have altered profiles of fecal bile acids(BAs).It was observed that BA receptors Takeda G-protein-coupled receptor 5(TGR5)and vitamin D receptor(VDR)participate in intestinal inflammatory responses by regulating NF-ĸB signaling.We hypothesized that altered profiles of fecal BAs might be correlated with gut microbiota and inflammatory responses in patients with UC.AIM To investigate the changes in fecal BAs and analyze the relationship of BAs with gut microbiota and inflammation in patients with UC.METHODS The present study used 16S rDNA sequencing technology to detect the differences in the intestinal flora between UC patients and healthy controls(HCs).Fecal BAs were measured by targeted metabolomics approaches.Mucosal TGR5 and VDR expression was analyzed using immunohistochemistry,and serum inflammatory cytokine levels were detected by ELISA.RESULTS Thirty-two UC patients and twenty-three HCs were enrolled in this study.It was found that the diversity of gut microbiota in UC patients was reduced compared with that in HCs.Firmicutes,Clostridium IV,Butyricicoccus,Clostridium XlVa,Faecalibacterium,and Roseburia were significantly decreased in patients with UC(P=3.75E-05,P=8.28E-07,P=0.0002,P=0.003,P=0.0003,and P=0.0004,respectively).Proteobacteria,Escherichia,Enterococcus,Klebsiella,and Streptococcus were significantly enriched in the UC group(P=2.99E-09,P=3.63E-05,P=8.59E-05,P=0.003,and P=0.016,respectively).The concentrations of fecal secondary BAs,such as lithocholic acid,deoxycholic acid,glycodeoxycholic acid,glycolithocholic acid,and taurolithocholate,in UC patients were significantly lower than those in HCs(P=8.1E-08,P=1.2E-07,P=3.5E-04,P=1.9E-03,and P=1.8E-02,respectively)and were positively correlated with Butyricicoccus,Roseburia,Clostridium IV,Faecalibacterium,and Clostridium XlVb(P<0.01).The concentrations of primary BAs,such as taurocholic acid,cholic acid,taurochenodeoxycholate,and glycochenodeoxycholate,in UC patients were significantly higher than those in HCs(P=5.3E-03,P=4E-02,P=0.042,and P=0.045,respectively)and were positively related to Enterococcus,Klebsiella,Streptococcus,Lactobacillus,and pro-inflammatory cytokines(P<0.01).The expression of TGR5 was significantly elevated in UC patients(0.019±0.013 vs 0.006±0.003,P=0.0003).VDR expression in colonic mucosal specimens was significantly decreased in UC patients(0.011±0.007 vs 0.016±0.004,P=0.033).CONCLUSION Fecal BA profiles are closely related to the gut microbiota and serum inflammatory cytokines.Dysregulation of the gut microbiota and altered constitution of fecal BAs may participate in regulating inflammatory responses via the BA receptors TGR5 and VDR.

Effect of Qinggan Huayu granule on H22 liver ascitic tumor mice

Objective:To evaluate the therapeutic effect of Qinggan Huayu granule on mice with H22 liver cancer ascites tumor.Methods:A H22 liver cancer ascites mouse model was established by intraperitoneally injecting H22 liver cancer cells.Mice were randomly divided into the model group,the Ganfule group(1.35 g/kg),the fluorouracil group(50 mg/kg i.p),the Qinggan Huayu granule groups at low(0.67 g/kg),medium(1.34 g/kg),and high(2.68 g/kg)doses.Then the mice were administered continuously for 10 days and body weight and abdominal circumference were monitored every 3 days.On day 11,eight rats in each group were randomly selected for dissection to detect the amount of peritoneal water,peritoneal permeability and histopathological changes.The remaining mice were observed for survival.In addition,the vascular endothelial growth factor A(VEGFA)and vascular endothelial growth factor receptor 2(VEGFR2)were determined by Western blotting.Results:Compared with the model group,the weight growth of mice in the fluorouracil group and the medium-dose and high-dose Qinggan Huayu granule groups was slower(P<0.05).Moreover,the abdominal circumference of mice in each treatment group was increased slowly.There were significant differences in abdominal circumference between the fluorouracil group,the medium-dose group and the control group from day 6(P<0.05)while the abdominal circumference of the high dose group was significantly smaller than that of the control group from day 12(P<0.05).Moreover,compared with the model group,the amount of ascites in the medium-and high-dose Qinggan Huayu granule groups was decreased significantly(P<0.05).The optical density value of ascites supernatant in medium-and high-dose Qinggan Huayu granule group and the fluorouracil group decreased significantly(P<0.05)and the survival period of the medium-dose Qinggan Huayu granule group and the fluorouracil group was prolonged prominently(P<0.05).There was no significant difference in the low-dose Qinggan Huayu granule group and the Ganfule group.Peritoneal histopathological assay showed more complete peritoneal structure,less edema and less angiogenesis of the peritoneum in the fluorouracil group and the medium-and high-dose Qinggan Huayu granule group,which was better than that of the Ganfule group and the low-dose group.Compared with the model group,the expressions of VEGFA and VEGFR2 in the medium-dose Qinggan Huayu granule group decreased significantly(P<0.05,P<0.01).Conclusion:Qinggan Huayu granule can inhibit ascites production in the mice model with H22 liver cancer ascites tumor,prolong the survival of mice,and reduce peritoneal permeability and suppress the increase of peritoneal neovascularization.The mechanism may be related to the inhibition of VEGF/VEGFR pathway.