The Impact of Synbiotic Treatment on the Levels of Gut-Derived Uremic Toxins, Inflammation, and Gut Microbiome of Chronic Kidney Disease Patients-A Randomized Trial.

Altering dysbiotic gut flora through synbiotic supplementation has recently been recognized as a potential treatment strategy to reduce the levels of gut-derived uremic toxins and decrease inflammation. Assessing its efficacy and safety has been the main goal of our randomized, double-blind, placebo-controlled study. A total of 34 nondialyzed chronic kidney disease patients, aged ≥18 years, with an estimated glomerular filtration rate between 15 and 45 mL/minute, were randomized either to an intervention group (n = 17), receiving synbiotic (Lactobacillus acidophilus, Lactobacillus casei, and Bifidobacterium lactis, 32 billion colony forming units per day plus 3.2 g of inulin), or control group (n = 17), receiving placebo during 12 weeks. The impact of treatment on the dynamic of serum levels of gut-derived uremic toxins, total serum indoxyl sulfate, p-cresyl sulfate, and trimethylamine N-oxide, was defined as the primary outcome of the study. Secondary outcomes included changes in the stool microbiome, serum interleukin-6 levels, high-sensitivity C-reactive protein, estimated glomerular filtration rate, albuminuria, diet, gastrointestinal symptom dynamics, and safety. Serum levels of uremic toxins were determined using ultraperformance liquid chromatography. The stool microbiome analysis was performed using the 16S ribosomal ribonucleic acid gene sequencing approach. Synbiotic treatment significantly modified gut microbiome with Bifidobacteria, Lactobacillus, and Subdoligranulum genera enrichment and consequently reduced serum level of indoxyl sulfate (ΔIS -21.5% vs. 5.3%, P < .001), improved estimated glomerular filtration rate (ΔeGFR 12% vs. 8%, P = .029), and decreased level of high-sensitivity C-reactive protein (-39.5 vs. -8.5%, P < .001) in treated patients. Two patients of the intervention arm complained of increased flatulence. No other safety issues were noted. Synbiotics could be available, safe, and an effective therapeutic strategy we could use in daily practice in order to decrease levels of uremic toxins and microinflammation in chronic kidney disease patients.

Mitrović M ，Stanković-Popović V ，Tolinački M ，Golić N ，Soković Bajić S ，Veljović K ，Nastasijević B ，Soldatović I ，Svorcan P ，Dimković N ... -  《-》

Synbiotics Easing Renal Failure by Improving Gut Microbiology (SYNERGY): A Randomized Trial.

The generation of key uremic nephrovascular toxins, indoxyl sulfate (IS), and p-cresyl sulfate (PCS), is attributed to the dysbiotic gut microbiota in CKD. The aim of our study was to evaluate whether synbiotic (pre- and probiotic) therapy alters the gut microbiota and reduces serum concentrations of microbiome-generated uremic toxins, IS and PCS, in patients with CKD. Predialysis adult participants with CKD (eGFR=10-30 ml/min per 1.73 m(2)) were recruited between January 5, 2013 and November 12, 2013 to a randomized, double-blind, placebo-controlled, crossover trial of synbiotic therapy over 6 weeks (4-week washout). The primary outcome was serum IS. Secondary outcomes included serum PCS, stool microbiota profile, eGFR, proteinuria-albuminuria, urinary kidney injury molecule-1, serum inflammatory biomarkers (IL-1β, IL-6, IL-10, and TNF-α), serum oxidative stress biomarkers (F2-isoprostanes and glutathione peroxidase), serum LPS, patient-reported health, Gastrointestinal Symptom Score, and dietary intake. A prespecified subgroup analysis explored the effect of antibiotic use on treatment effect. Of 37 individuals randomized (age =69±10 years old; 57% men; eGFR=24±8 ml/min per 1.73 m(2)), 31 completed the study. Synbiotic therapy did not significantly reduce serum IS (-2 μmol/L; 95% confidence interval [95% CI], -5 to 1 μmol/L) but did significantly reduce serum PCS (-14 μmol/L; 95% CI, -27 to -2 μmol/L). Decreases in both PCS and IS concentrations were more pronounced in patients who did not receive antibiotics during the study (n=21; serum PCS, -25 μmol/L; 95% CI, -38 to -12 μmol/L; serum IS, -5 μmol/L; 95% CI, -8 to -1 μmol/L). Synbiotics also altered the stool microbiome, particularly with enrichment of Bifidobacterium and depletion of Ruminococcaceae. Except for an increase in albuminuria of 38 mg/24 h (P=0.03) in the synbiotic arm, no changes were observed in the other secondary outcomes. In patients with CKD, synbiotics did not significantly reduce serum IS but did decrease serum PCS and favorably modified the stool microbiome. Large-scale clinical trials are justified.

Rossi M ，Johnson DW ，Morrison M ，Pascoe EM ，Coombes JS ，Forbes JM ，Szeto CC ，McWhinney BC ，Ungerer JP ，Campbell KL ... -  《-》

Synbiotics Easing Renal Failure by Improving Gut Microbiology II (SYNERGY II): A Feasibility Randomized Controlled Trial.

McFarlane C ，Krishnasamy R ，Stanton T ，Savill E ，Snelson M ，Mihala G ，Kelly JT ，Morrison M ，Johnson DW ，Campbell KL ... -  《Nutrients》

The Effect of Synbiotic Supplementation on Uremic Toxins, Oxidative Stress, and Inflammation in Hemodialysis Patients-Results of an Uncontrolled Prospective Single-Arm Study.

Kuskunov T ，Tilkiyan E ，Doykov D ，Boyanov K ，Bivolarska A ，Hristov B ... -  《-》

Effects of synbiotic supplementation on microbiota-derived protein-bound uremic toxins, systemic inflammation, and biochemical parameters in patients on hemodialysis: A double-blind, placebo-controlled, randomized clinical trial.

The generation of key nephrovascular protein-bound uremic toxins, indoxyl sulfate and phenol, in hemodialysis (HD) patients is attributed to the dysbiotic gut microbiota. The aim of this study was to investigate the effects of synbiotic supplementation on serum levels of indoxyl sulfate, phenol, inflammation, and biochemical parameters in HD patients. Forty-two HD patients (synbiotic group: n = 21; placebo group: n = 21) were analyzed in this randomized, double-blind, placebo-controlled study. During a 2-mo intervention, the synbiotic group received two synbiotic capsules daily, between the main meals, whereas the placebo group received maltodextrin as the placebo. Blood pressure, uremic factors, and biochemical parameters were assessed before the start and after the end of the study. After adjustment for potential confounders, there was no significant effect of synbiotic on serum levels of urea, creatinine, liver enzymes, high-sensitivity C-reactive protein, sodium, potassium, phosphorus, blood pressure, or albumin in the treatment group compared with the placebo group. A significant increase in indoxyl sulfate and parathyroid hormone levels were observed only in the treatment group. However, between-group analyses were not significant. Compared with baseline values, phenol levels were decreased in both groups (P≤001), with no significant between-group difference. Synbiotic supplementation might increase indoxyl sulfate and parathyroid hormone levels in HD patients.

Mirzaeian S ，Saraf-Bank S ，Entezari MH ，Hekmatdoost A ，Feizi A ，Atapour A ... -  《-》