Regional variation and diagnosis modeling of gut microbiome for inflammatory bowel diseases / 中华检验医学杂志

Objective To identify microbiome biomarkers in patients with inflammatory bowel disease ( IBD) in different regions and establish predictive models , and to explore the various gut microbiota function in IBD patients .Methods The 16 srRNA gene sequences of 1510 IBD patients and 496 healthy controls were collected from China , the United States ( RISK and PRISM cohort ), Germany, India and Lithuania cohort.QIIME ( v1.9.1) was used to analyze microbiota data.LEfSe was used to identify biomarkers for IBD.Random forest method was used to establish the prediction model to distinguish IBD from HC.PICRUSt was used to predict the functional changes of gut microbiota in IBD patients .Resultsɑdiversity of gut microbial in IBD patients was significantly lower than in HC (Wilcoxon,P<0.05).The gut microbiota of IBD patients was different from HC significantly ( Adonis,P<0.05) in all of the cohort study but Indian.LEfSe analysis showed that the IBD patients from China and the U .S.cohort harbored similar dysbiosis patterns , while those from Lithuania , Germany and India have highly localized dysbiosis patterns.Generally, enterococcus was significantly increased in IBD patients in China , the U.S.and Germany cohort.Enterobacteriaceae was significantly increased in IBD patients in China and the U .S. cohort.Ruminococcus was significantly decreased in the intestines of IBD patients in China , the U.S.and India cohort.When predicting IBD status using machine learning models built on local population , the area under the curve ( AUC) was 86.48％ ±4.91％.Meanwhile, when predicting IBD status using machine learning models built on other populations , China and the U.S.had a relatively high AUC for cross-predicting, whilethe other pairs were failed when cross-applied to each other.The model established based on all samples was used to predict each population ,which showed that China , the United States ( RISK and PRISM cohort ), Germany, Lithuania and India cohorts having AUCs of 90.1％, 82.3％, 79.6％, 61.9％, 65.5％and 54.2％respectively.For functional analysis, in China, the United States (RISK and PRISM cohort ) and India cohort , glutathione metabolism and quinones biosynthesis was significantly increased in IBD patients.In China, Germany and Lithuania cohort , flagella assembly and bacterial motility proteins functions were significantly decreased in the IBD patients .Conclusions The intestinal microbiota of IBD patients from different countries could have consistent dysbiosis patterns , but geographical factors still exert a great effect on the microbiota , which needs to be further explored in subsequent studies .

Enteric dysbiosis-linked gut barrier disruption triggers early renal injury induced by chronic high salt feeding in mice

Chronic high-salt diet-associated renal injury is a key risk factor for the development of hypertension. However, the mechanism by which salt triggers kidney damage is poorly understood. Our study investigated how high salt (HS) intake triggers early renal injury by considering the ‘gut-kidney axis’. We fed mice 2% NaCl in drinking water continuously for 8 weeks to induce early renal injury. We found that the ‘quantitative’ and ‘qualitative’ levels of the intestinal microflora were significantly altered after chronic HS feeding, which indicated the occurrence of enteric dysbiosis. In addition, intestinal immunological gene expression was impaired in mice with HS intake. Gut permeability elevation and enteric bacterial translocation into the kidney were detected after chronic HS feeding. Gut bacteria depletion by non-absorbable antibiotic administration restored HS loading-induced gut leakiness, renal injury and systolic blood pressure elevation. The fecal microbiota from mice fed chronic HS could independently cause gut leakiness and renal injury. Our current work provides a novel insight into the mechanism of HS-induced renal injury by investigating the role of the intestine with enteric bacteria and gut permeability and clearly illustrates that chronic HS loading elicited renal injury and dysfunction that was dependent on the intestine.

THE STUDY OF LOW SODIUM SALT DIET / 营养学报

34 medical college students and 26 patients with primary hypertension were served as the subjects on low sodium salt diet for 4 weeks. Before and after the experiment, serum and urinary sodium and potassium, as well as blood presure, pulse rate, and body weight were measured. During the testing period, calorie and protein were supplied sufficiently and the salt content in their common diet taken was restricted strictly. The results showed that the serum sodium decreased, potassium increased at the end of the experiment, but the changes were all within the physiological permissible limits. On the contrary, urinary sodium increased, potassium decreased and the Na/K dropped markedly, body weight increased slightly in healthy subjects and decreased by 1.0-3.0kg in patients with hypertension. The blood pressure, both systolic and diastolic, was decreased but no change in the pulse rate was observed.It was obvious that in the subjects on common salt diet, the body sodium was high and potassium low, otherwise on low sodium salt diet, such situation might be improved, and the high blood pressure could also be ameliorated in the type Ⅰ and Ⅱ of hypertension.