Effects of Propolis Supplementation on Gut Microbiota and Uremic Toxin Profiles of Patients Undergoing Hemodialysis
Larissa Fonseca,
Marcia Ribeiro,
Júnia Schultz,
Natália A. Borges,
Ludmila Cardozo,
Viviane O. Leal,
Marcelo Ribeiro-Alves,
Bruna R. Paiva,
Paulo E. C. Leite,
Carmen L. Sanz,
Fernanda Kussi,
Lia S. Nakao,
Alexandre Rosado,
Peter Stenvinkel,
Denise Mafra
Affiliations
Larissa Fonseca
Graduate Program in Medical Sciences, Fluminense Federal University (UFF), Niteroi 24033-900, Brazil
Marcia Ribeiro
Graduate Program in Biological Sciences-Physiology, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro 20550-170, Brazil
Júnia Schultz
Bioscience Program, Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Makkah 23955, Saudi Arabia
Natália A. Borges
Institute of Nutrition, Rio de Janeiro State University (UERJ), Rio de Janeiro 20550-170, Brazil
Ludmila Cardozo
Graduate Program in Cardiovascular Sciences, Fluminense Federal University (UFF), Niteroi 24033-900, Brazil
Viviane O. Leal
Nutrition Division, Pedro Ernesto University Hospital (UERJ), Rio de Janeiro 20550-170, Brazil
Marcelo Ribeiro-Alves
HIV/AIDS Clinical Research Center, National Institute of Infectology (INI/Fiocruz), Rio de Janeiro 20550-170, Brazil
Bruna R. Paiva
Graduate Program in Cardiovascular Sciences, Fluminense Federal University (UFF), Niteroi 24033-900, Brazil
Paulo E. C. Leite
Graduate Program in Science and Biotechnology, Fluminense Federal University (UFF), Niteroi 24033-900, Brazil
Carmen L. Sanz
Department of Basic Pathology, Federal University of Paraná, Curitiba 81530-000, Brazil
Fernanda Kussi
Department of Basic Pathology, Federal University of Paraná, Curitiba 81530-000, Brazil
Lia S. Nakao
Department of Basic Pathology, Federal University of Paraná, Curitiba 81530-000, Brazil
Alexandre Rosado
Bioscience Program, Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Makkah 23955, Saudi Arabia
Peter Stenvinkel
Division of Renal Medicine, Department of Clinical Science, Technology and Intervention, Karolinska Institutet, 17165 Stockholm, Sweden
Denise Mafra
Graduate Program in Medical Sciences, Fluminense Federal University (UFF), Niteroi 24033-900, Brazil
Background: Propolis possesses many bioactive compounds that could modulate the gut microbiota and reduce the production of uremic toxins in patients with chronic kidney disease (CKD) undergoing hemodialysis (HD). This clinical trial aimed to evaluate the effects of propolis on the gut microbiota profile and uremic toxin plasma levels in HD patients. These are secondary analyses from a previous double-blind, randomized clinical study, with 42 patients divided into two groups: the placebo and propolis group received 400 mg of green propolis extract/day for eight weeks. Indole-3 acetic acid (IAA), indoxyl sulfate (IS), and p-cresyl sulfate (p-CS) plasma levels were evaluated by reversed-phase liquid chromatography, and cytokines were investigated using the multiplex assay (Bio-Plex Magpix®). The fecal microbiota composition was analyzed in a subgroup of patients (n = 6) using a commercial kit for fecal DNA extraction. The V4 region of the 16S rRNA gene was then amplified by the polymerase chain reaction (PCR) using short-read sequencing on the Illumina NovaSeq PE250 platform in a subgroup. Forty-one patients completed the study, 20 in the placebo group and 21 in the propolis group. There was a positive correlation between IAA and TNF-α (r = 0.53, p = 0.01), IL-2 (r = 0.66, p = 0.002), and between pCS and IL-7 (r = 0.46, p = 0.04) at the baseline. No significant changes were observed in the values of uremic toxins after the intervention. Despite not being significant, microbial evenness and observed richness increased following the propolis intervention. Counts of the Fusobacteria species showed a positive correlation with IS, while counts of Firmicutes, Lentisphaerae, and Proteobacteria phyla were negatively correlated with IS. Two months of propolis supplementation did not reduce the plasma levels of uremic toxins (IAA, IS, and p-CS) or change the fecal microbiota.
