Study On The Changes Of Intestinal Microflora And Serum Inflammatory Cytokines In Patients With Irritable Bowel Syndrome

BackgroundIrritable bowel syndrome is the highest incidence of human functional bowel disease,more and more evidences prove that the intestinal flora structure is one of the key reasons for the pathogenesis of IBS,studies have found that the incidence of IBS were significantly correlated with inflammatory factor levels.The changes of intestinal flora have direct or indirect effects on intestinal mucosal protection and cell proliferation,which may induce IBS.ObjectiveTo study in patients with irritable bowel syndrome in the intestinal flora structure changes and serum inflammatory cytokines :IL-6,IL-13,IL-18.Through the study of the intestinal flora,serum cytokine levels revealed the possible pathogenesis of IBS,so as to provide new ideas for the treatment way of IBS.Methods(1)According to the diagnostic criteria of ROME ?.IBS patients selected were derived from the digestive department of Tai'an City Central Hospital.The healthy subjects were selected from Tai'an cityas and by random selection method.Fresh morning fecal and fasting peripheral blood serum were collected as experimental specimens.(2)The samples were extracted by the method of extracting DNA from human fecal genomic DNA.(3)Real time PCR method was used to detect the circulating threshold(Ct value)of different intestinal bacteria.(4)Enzyme linked immunosorbent assay(ELISA)was used to detect the concentrations of proinflammatory cytokines IL-6,IL-18 and IL-13 in the peripheral blood of the target population.(5)GraphPad Prism 5 Microsoft,Excel-2003 statistical software was used for TTEST analysis and correlation analysis.Results1.According to the diagnostic criteria of ROME ?IBS,39 patients with IBS were selected,the average age was 51.86 years old,the proportion of male and female was 2:3;28 healphy members were selected as control group which average age was 34.23 year old,the proportion of male and female was 2:3.2.The size of the target gene fragment was consistent with the size of the total intestinal flora of human feces.The effective rate of the standard curve was in the range of 1.958-2.105.Indicating that the recombinant plasmid was successfully constructed in this experiment.3.The recombinant plasmid was used as a quantitative reference to confirm the replication of the total intestinal flora,Escherichia coli,Lactobacillus,Enterococcus,Bacteroides,Bacteroides,Clostridium perfringens,Bacteroides and Bifidobacterium Quantity.The average number of Escherichia coli and enterococcus increased significantly(p<0.01),there was statistical significance;The number of seen,Eumycota,Bifidobacterium,quasi decreased(p<0.05),there was statistical significance;The average number of aerogenesis was increased,but p> 0.05,no significant difference The average copy number of lactobacillus decreased significantly,but p>0.05,no statistical significance.Staphyl ococcus aureus and Bacteroides in the total intestinal flora accounted for the largest proportion.The percentage of Firmicutes divisionin the healthy control group was 34%,and in the IBS group was 22%.The percentage of Bacteroides flora in the healthy control group was 59%,and in the IBS group was 36%;followed by E.coli,the proportion of the control group is almost 0%,while The proportion of IBS patients increased by 1%.4.The expression of IL-6 and IL-18 in IBS patients was significantly higher than normal controls(p<0.01).The mean concentration of IL-13 in IBS patients was lower than that in normal group,but p>0.05,which was not statistically significant.5.E.coli and IL-6,IL-18 showed significant positive correlation(r>0)0,and negative correlation with IL-13(r<0);Bacteroidetes bacteria,Firmicutes and IL-6,IL-18 showed a negative correlation(r<0),but showed a significant positive correlation with IL-13(r>0).Conclusions1.The pathogenesis of irritable bowel syndrome is related to the change of intestinal flora.The number of probiotics group decreased,the number of pathogenic bacteria increased,and the number of harmful bacteria increased.2.The expression of inflammatory cytokines in patients with IBS increased,which suggesting that there may be immune activation.3.There is a significant correlation between the changes of the structure of the intestinal flora and its metabolic substances and serum inflammatory cytokines in patients with irritable bowel syndrome.4.The flora structure and level of inflammatory cytokines in patients with IBS may provide a new idea for clinical treatment.