Abstract
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.