Synbiotics alleviate the gut indole load and dysbiosis in chronic kidney disease

Chih Yu Yang, Ting Wen Chen, Wan Lun Lu, Shih Shin Liang, Hsien Da Huang, Ching Ping Tseng*, Der Cherng Tarng*

*Corresponding author for this work

Research output: Contribution to journalJournal Article peer-review

25 Scopus citations


Chronic kidney disease (CKD) has long been known to cause significant digestive tract pathology. Of note, indoxyl sulfate is a gut microbe-derived uremic toxin that accumulates in CKD patients. Nevertheless, the relationship between gut microbiota, fecal indole content, and blood in-doxyl sulfate level remains unknown. In our study, we established an adenine-induced CKD rat model, which recapitulates human CKD-related gut dysbiosis. Synbiotic treatment in CKD rats showed a significant reduction in both the indole-producing bacterium Clostridium and fecal indole amount. Furthermore, gut microbiota diversity was reduced in CKD rats but was restored after synbiotic treatment. Intriguingly, in our end-stage kidney disease (ESKD) patients, the abundance of indole-producing bacteria, Bacteroides, Prevotella, and Clostridium, is similar to that of healthy con-trols. Consistently, the fecal indole tends to be higher in the ESKD patients, but the difference did not achieve statistical significance. However, the blood level of indoxyl sulfate was significantly higher than that of healthy controls, implicating that under an equivalent indole production rate, the impaired renal excretion contributes to the accumulation of this notorious uremic toxin. On the other hand, we did identify two short-chain fatty acid-producing bacteria, Faecalibacterium and Rose-buria, were reduced in ESKD patients as compared to the healthy controls. This may contribute to gut dysbiosis. We also identified that three genera Fusobacterium, Shewanella, and Erwinia, in the ESKD patients but not in the healthy controls. Building up gut symbiosis to treat CKD is a novel concept, but once proved effective, it will provide an additional treatment strategy for CKD patients.

Original languageEnglish
Article number114
Pages (from-to)1-15
Number of pages15
Issue number1
StatePublished - 01 2021
Externally publishedYes

Bibliographical note

Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.


  • Chronic kidney disease
  • Dysbiosis
  • Gut indole
  • Synbiotics


Dive into the research topics of 'Synbiotics alleviate the gut indole load and dysbiosis in chronic kidney disease'. Together they form a unique fingerprint.

Cite this