The protein metabolite hypothesis, a model for the progression of renal failure: an oral adsorbent lowers indoxyl sulfate levels in undialyzed uremic patients
Niwa, T.; Nomura, T.; Sugiyama, S.; Miyazaki, T.; Tsukushi, S.; Tsutsui, S.
Kidney International. Supplement 62: S23-S28
1997
ISSN/ISBN: 0098-6577 PMID: 9350673 Document Number: 477995
We have recently demonstrated that indoxyl sulfate promotes the progression of glomerular sclerosis in uremic rats. In the present study, we determined whether an oral adsorbent (AST-120) could reduce the serum and urine levels of indoxyl sulfate and suppress the progression of chronic renal failure (CRF) in undialyzed uremic patients. Twenty-five undialyzed uremic patients were given AST-120 at a dose of 6 g/day for 6 months, while 10 undialyzed uremic patients were not given AST-120. The effects of the oral adsorbent on the slope of the 1/serum creatinine (S-Cr)-time plot, and the serum and urine levels of indoxyl change in the slope of the 1/S-Cr-time plot showed a significant negative correlation with the change in the urine level of indoxyl sulfate. Thus, patients who showed a greater decrease of urinary indoxyl sulfate also showed more marked suppression of the progression of CRF. These results support the notion that indoxyl sulfate, a protein metabolite, is involved in the progression of CRF, and that an oral adsorbent can delay progression at least partly by reducing the serum and urine levels of indoxyl sulfate.