| Abstract
Introduction: Gut derived toxins such as p-cresol, p-cresyl sulfate (pCS) and indoxyl sulfate (IS), which belong to
protein-bound uremic toxins that promote development of fibrosis inflammatory state associated with chronic
kidney disease. One possible way to suppress the production of IS and pCS is to increase dietary fiber intake. The
aim of the present study was to assess whether increasing dietary fiber, as high amylose diet, can affect the level of
conventional and protein bound nitrogenous products.
Methods: Fifty patients with end stage renal disease (ESRD) on maintenance hemodialysis were randomly assigned
to receive a diet containing resistant starch (HAM-RS2) or placebo over 8 weeks spanning February and September
2017 in the 29 Bahman hospital hemodialysis ward in Tabriz, Iran. Of these, 44 patients (23 from HAM-RS2 and 21
control) completed the study. Plasma levels of urea, creatinine, uric acid and other routine parameters were
measured at the beginning and after 8 weeks of starting the supplementation. The levels of IS and p-cresol in the
collected serum samples were also determined by HPLC at baseline and after intervention.
Results: There was significant reduction of creatinine and uric acid levels in HAM-RS2 supplemented patients when
compared with control group (P < 0.05). Serum levels of IS was not changed significantly in both HAM-RS2 treated
and control patients, whereas p-cresol level was reduced significantly during the study period in HAM-RS2 treated
patients (P = 0.039). The change of other parameters including Hb, lipids, bone markers and hs-CRP were nonsignificant
during the study in both groups.
Conclusion: Administration of fermentable high fiber diet as HAM-RS2 decreased serum levels of some
nitrogenous products such as serum creatinine and p-cresol as a gut derived nitrogenous product without change
in IS levels in maintenance hemodialysis patients. Due to safety, without important side effects the administration
of diet enriched with fermentable fiber is suitable for patients on maintenance dialysis.
Keywords: Chronic kidney disease, Gut microbiota, P-cresol, Short chain fatty acid, Dietary |