Dietary composition modulate gut microbiota and related biomarkers in patients with chronic kidney disease

Emerging evidence indicates gut microbiota is essential to chronic kidney disease (CKD) progression. This study investigated the association between gut microbiota profiles, plasma trimethylamine-N-oxide (TMAO), and circulating inflammatory markers in CKD patients according to dietary patterns, particularly low-protein, high-fiber (LP-HF) versus high-protein, low-fiber (HP-LF) diet. In this cross-sectional study, patients with non-dialysis CKD and healthy subjects were enrolled. Dietary patterns among participants were assessed using three-day diet records with detailed nutrient analysis. The 16 S ribosomal RNA sequencing was conducted to examine fecal gut microbiota composition. Plasma samples were analyzed for TMAO concentration and cytokine levels. A total of 135 CKD patients were recruited. A distinct shift in gut microbiota composition in CKD patients was observed compared to 19 healthy controls, particularly a significant reduction of short-chain fatty acid (SCFA)-producing bacteria. TMAO and several cytokine levels were significantly elevated in CKD patients compared to healthy subjects. Within CKD, patients with LP-HF diet displayed a greater abundance of SCFA-producing bacteria, such as the Lachnospiraceae NK4A136 group and Eubacterium ruminantium group, than those with the HP-LF diet. The HP-LF subgroup showed enriched proteolytic bacterial genera such as Klebsiella. The HP-LF subgroup also exhibited significantly higher plasma levels of TMAO, interleukin (IL)-18, and monocyte chemoattractant protein-1 (MCP-1). CKD patients displayed marked alterations in gut bacterial composition compared to healthy controls. Our results also highlighted the potential advantages of adopting a high fiber-rich and low-protein diet intake in reducing gut dysbiosis in CKD patients.