Bifidobacterium in gastro-resistant seamless capsule reduces serum levels of indoxyl sulfate in patients on hemodialysis

Background: Intestinal microflora is deranged in hemodialysis (HD) patients as increased aerobacteria such as Escherichia coli, and decreased anaerobacteria such as bifidobacteria. Indole, a precursor of indoxyl sulfate, is produced by E. coli but not by bifidobacteria. The serum levels of indoxyl sulfate are increased markedly in HD patients and cannot be reduced efficiently by HD because of its albumin binding. Methods: To compare the effect of oral administration of Bifidobacterium longum in gastro-resistant seamless capsule (Bifina) on indoxyl sulfate levels with that of Bifidobacteria in powder formulation (Lac B), Bifina was administered to 11 HD patients for 5 weeks, and Lac B to another group of 11 HD patients for 5 weeks. The authors measured the serum level of indoxyl sulfate by using high-performance liquid chromatography. Results The pre-HD serum levels of indoxyl sulfate significantly decreased in Bifina-treated patients (before, 4.9 +/- 1.7 mg/dL, 4.5 mg/dL, mean +/- SD, median, after 5 weeks, 3.5 +/- 1.3 mg/dL, 3.8 mg/dL; P < 0.005). However, they did not decrease in the Lac B-treated patients (before, 4.8 +/- 1.4 mg/dL, 4.5 mg/dL, after 5 weeks, 5.2 +/- 2.0 mg/dL, 5.1 mg/dL). Conclusion: Oral administration of Bifina to HD patients is effective in reducing the serum levels of indoxyl sulfate by correcting the intestinal microflora. Gastro-resistant seamless capsule prevents bifidobacteria from its inactivation in acidic gastric juice, and allows it to be actived in the intestine.