Effects of AST-120 on blood concentrations of protein-bound uremic toxins and biomarkers of cardiovascular risk in chronic dialysis patients

Background: Removal of protein-bound uremic toxins by dialysis therapy is limited. The effect of oral adsorbent AST-120 in chronic dialysis patients has rarely been investigated. Methods: AST-120 was administered 6.0 g/day for 3 months in 69 chronic dialysis patients. The blood concentrations of indoxyl sulfate, p-cresol sulfate and biomarkers of cardiovascular risk were determined before and after AST-120 treatment. Results: AST-120 significantly decreased both the total and free forms of indoxyl sulfate and p-cresol sulfate ranging from 21.9 to 58.3%. There were significant simultaneous changes of the soluble tumor necrosis factor-like weak inducer of apoptosis (sTWEAK, 24% increase), malondialdehyde (14% decrease) and interleukin-6 (19% decrease). A significant association between the decrease of indoxyl sulfate and changes of sTWEAK and interleukin-6 was noted. Conclusions: AST-120 effectively decreased indoxyl sulfate and p-cresol sulfate levels in both total and free forms. AST-120 also improved the profile of cardiovascular biomarkers.