The Profile and Function of Gut Microbiota in Chronic Kidney Disease

Abstract Objective: The gut microbiota was considered to be an important hidden "organ" of the human body, which was of great significance in maintaining the body's physiology and pathological regulation. Previous studies had found that the gut microbiota was closely related to various diseases, but there was no unified conclusion on the distribution characteristics of the gut microbiota in chronic kidney disease (CKD) and its relationship with the progression of CKD. In this study, we tried to investigate the profile and function of gut microbiota in CKD and its relationship with the progression of CKD. Methods: A total of 80 people were enrolled in this study. Twenty were healthy people, and 60 were CKD patients. The CKD patients were divided into three stages including stage 3, 4, and 5. We conducted taxonomic analyses in different groups. The distributions of phyla, classes, orders, families and genera in different groups and samples were investigated. We also evaluated the correlations between clinical parameters and gut microbiota in 60 CKD patients. Results: The gut microbiota in the healthy group and CKD group had 2351 operational taxonomic units (OTUs) in total. The healthy group had 1076 OTUs, and the CKD group had 2259 OTUs. The diversity of gut microbiota in the stage 3 CKD group was smaller than that in the other groups. Bacteroides was positively correlated with serum creatinine (Scr) and serum cholesterol, while was negatively correlated with albumin (ALB), haemoglobin, and estimated glomerular filtration rate (eGFR). Blautia was positively correlated with Scr, blood urea nitrogen (BUN), 24-hour urine protein (24-h UTP), and serum cholesterol, while was negatively correlated with haemoglobin and eGFR。Bifidobacterium was positively correlated with eGFR, while was negatively correlated with Scr and BUN. Prevotella was negatively correlated with BUN, while was positively correlated with haemoglobin. Megamonas was negatively correlated with BUN, while was positively correlated with haemoglobin and eGFR. Subdoligranulum was negatively correlated with UA. Parabacteroides and megasphaera were positively correlated with serum cholesterol. Klebsiella was negatively correlated with haemoglobin. Conclusions: The gut microbiota might be one of the important pathological mechanisms underlying the development and progression of CKD. The changes of diversity in gut microbiota were associated with disease progression. Some kinds of gut microbiota including bacteroides, blautia, parabacteroides, megasphaera and klebsiella might be detrimental factors in CKD, while other kinds of gut microbiota including bifidobacterium, prevotella, megamonas and subdoligranulum might be beneficial factors in CKD.