16s RRNA Sequencing-based Correlation Study On The Differences In Gut Microbiota Between Patients With Idiopathic Membranous Nephropathy And Their Co-residents

Background and purposeAt present,the pathogenesis of idiopathic membranous nephropathy(IMN)is not clear,which may be related to environmental pollution,heredity and autoimmunity.In recent years,some studies have found that the intestinal mucosal barrier in IMN patients is damaged,but the mechanism of this damage is not clear.Therefore,this study aims to understand the gut-kidney axis by analyzing the gut microbiota composition of biopsy-confirmed IMN patients and their healthy relatives,and to provide new ideas for the treatment of membranous nephropathy.MethodsThirty patients with IMN diagnosed by renal biopsy between May 2019 and December 2020 were Harbin Medical University as IMN Group,a total of 30 healthy co-habitants served as control group(HC Group).Feces from all participants were collected and microbiota composition was analyzed by 16 S rRNA sequencing.The scarcity curve was used to assess the adequacy of the sample size.Α diversity analysis,β diversity analysis and LEf Se analysis were used to explore the differences of intestinal flora between the two groups.Spearman’s rank correlation coefficient was used to study the correlation between intestinal flora and clinical indexes in IMN patients.RF analysis and ROC curve were used to search for potential intestinal flora markers in IMN patients,the function of intestinal flora in IMN patients was predicted by PICRUST analysis.Results1.There was no significant difference in sex,age and BMI between IMN Group and HC Group.2.The α diversity of IMN group was lower than that of HC Group(Chao1,P=0.048;Sobs index,P=0.024;Shannon index,P=0.016;Simpson index,P=0.032),and the βdiversity of IMN group was significantly different from that of HC Group(P=0.002,r=0.066).3.At the phylum level,the abundance of Proteobacteria in IMN group was higher than that in HC Group(P=0.015),while the abundance of Bacteroidetes in IMN group was significantly lower than that in HC Group(P=0.013),the IMN group had higher abundance of Citrobacter,Streptococcus and Enterobacter(P=0.024;P=0.008;P=0.023),however,the abundance of Faecalibacterium,Agathobacter,Bacteroides,subdoligranum,Ruminococcus and Fusicatenibacter in HC Group was lower than that in HC Group(P=0.046;P=0.002;P=0.008;P=0.003;P=0.005;P=0.004).4.Spearman’s rank correlation coefficient analysis showed that at the phylum level,Actinobacterioia was significantly negatively correlated with e GFR(r=-0.414,P=0.023),while Campilobacterota was positively correlated with LDL-C(r=0.375,P=0.041),and Bacteroidota was positively correlated with TP(r = 0.373,P=0.043)。 At the genus level,Bacteroides,Bifidobacterium,and Veillonella were significantly negatively correlated with TG(r=-0.420,P=0.021;r=-0.447,P=0.013;r=-0.555,P=0.001).Dorea was also negatively correlated with HDL-C(r=-0.390,P=0.033).Faecalibacterium and Roseburia were negatively associated with BMI(r=-0.409,P=0.024;r=-0.390,P=0.033).5.The results of RF analysis and ROC curve show that the area under the ROC curve of the combination of four genera(g＿＿Moryella,g＿＿Lachnospira,g＿＿Gemella,g＿＿Lachnospiraceae＿NC200 4＿group)is 0.96.6.The results of PICRUSt1 function prediction showed that the bacterial invasion of epithelial cells(ko05100),α-linolenic acid metabolism(ko00592),staphylococcus aureus infection(ko05150)and arachidonic acid metabolism(ko00590)pathway were statistically different(P=0.013;P=0.018;P=0.025;P=0.043).Conclusion1.There are differences between the gut microbiota of IMN patients and healthy family members living together.2.The difference in gut microbiota of IMN patients may have caused changes in clinical detection indicators and participated in the occurrence of IMN.3.The combination of four genera(g＿＿Moryella,g＿＿Lachnospira,g＿＿Gemella,g＿＿Lachnospiraceae＿NC200 4＿group)can be used as potential intestinal microbiota markers for IMN intestinal flora4.The gut microbiota of IMN patients is closely related to metabolic pathways related to lipid metabolism.