A cross-sectional study on gut microbiota and inflammation in patients with chronic kidney disease

Abstract

Background: This study investigated the inflammatory and gut microbiota profile in chronic kidney disease (CKD) patients undergoing hemodialysis (HD) and peritoneal dialysis (PD).

Methods: A total of 249 patients undergoing HD and 61 patients on PD participated in the study. The mRNA expressions of nuclear factor erythroid 2-related factor-2 (NRF2), nuclear factor-κappa B (NF-κB), mitochondrial transcription factor A (TFAM), peroxisome proliferator-activated receptor-gamma coactivator 1-alpha (PGC-1α) were evaluated in peripheral blood mononuclear cells (PBMCs) by quantitative real-time PCR. Malondialdehyde (MDA), interleukin 6 (IL-6), and routine biochemical parameters were also analyzed. The fecal DNA extraction was performed, and the V4 regions of the bacterial 16S ribosomal RNA gene were sequenced. Uremic toxins such as p-cresyl sulfate (p-CS), indoxyl sulfate (IS), and indole-3-acetic acid (IAA) plasma levels were determined by HPLC.

Results: MDA, IS, and p-CS levels were lower in PD than in HD patients. The mRNA expression of the transcription factors was not different between groups. Gut microbial α-diversity indices showed no significant difference between groups, but the β-diversity was different in PD patients. Members of the genera Meditarraneibacter, Roseburia, Agathobacter, Anaerobutyricum, Collinsella, Streptococcus, Clostridium, and Bacteroides, as well as the families Lachnospiraceae and Enterobacteriaceae, appear to be positively correlated with most dietary factors, particularly lipid and phosphorus intake.

Conclusions: Our findings indicate that in patients with CKD on HD, there is increased plasma retention of uremic toxins and reduced gut microbial diversity compared to PD patients.

Keywords: Chronic kidney disease; Gut microbiota; Inflammation; Mitochondrial dysfunction; Oxidative stress.