Effects of Cranberry Extract (Vaccinium macrocarpon) Supplementation on Lipid Peroxidation and Inflammation in Patients with Chronic Kidney Disease (Stages 3-4): A Randomized Controlled Trial.

Background: Growing evidence suggests that bioactive compounds in berry fruits may mitigate inflammation in patients with chronic kidney disease (CKD). Objectives: To evaluate cranberry (Vaccinium macrocarpon) supplementation effects on modulation of transcription factors involved in inflammation and oxidative stress in nondialysis (stages 3 and 4) patients with CKD. Design/Participants. A randomized, double-blind, placebo-controlled study was performed with 30 patients to receive capsules containing cranberry extract (1000 mg/day) or placebo (1000 mg/day of corn starch) for two months. Measurements. The mRNA expression of nuclear factor-erythroid 2-related factor-2 (Nrf2) and nuclear factor-kB (NF-kB) was evaluated in peripheral blood mononuclear cells (PBMCs) by quantitative real-time polymerase chain reaction. Thiobarbituric acid reactive substances (TBARS) were measured in the plasma to assess oxidative stress. Interleukin-6 (IL-6) plasma levels were assessed by enzyme-linked immunosorbent assay and C-reactive protein (CRP) by immunoturbidimetric method. Results: Twenty-five patients completed the study: 12 in the cranberry group (56.7 ± 7.5 years and body mass index (BMI) of 29.6 ± 5.5 kg/m2) and 13 in the placebo group (58.8 ± 5.1 years and BMI 29.8 ± 5.4 kg/m2). There were no differences in NF-kB or Nrf2 mRNA expressions (p = 0.99 and p = 0.89) or TBARS, CRP, and IL-6 plasma levels after cranberry supplementation. Conclusions: The cranberry extract administration (1000 mg/day) did not affect Nrf2 and NF-kB mRNA expression, oxidative stress, or inflammatory markers levels in nondialysis CKD patients. This trial is registered with NCT04377919.

Effects of Polydextrose Supplementation on Intestinal Function in Hemodialysis Patients: A Double-Blind, Randomized, Placebo-Controlled Trial.

OBJECTIVES: Intestinal constipation is a frequent complication in hemodialysis (HD) patients. Polydextrose (PDX), a nondigestible oligosaccharide, has been reported as a fermentable fiber with potential benefits. This study aimed to investigate the possible influence of PDX supplementation on intestinal function in HD patients. METHODS: This randomized, double-blind, placebo-controlled trial included 28 patients who received daily oral supplementation with 12 g of PDX or placebo (corn starch) for 2 months. ROME IV criteria were used to define constipation and questionnaires were applied to patient assessment of constipation symptoms (PAC-SYM) and their impact on the patient assessment of constipation quality of life. The Bristol scale was used to assess stool consistency. Commercial Enzyme-Linked Immuno Sorbent Assay kits were used to evaluate the interleukin-6 and tumor necrosis factor-α plasma levels. RESULTS: 25 patients completed the study; 16 in the PDX group [7 females, 48.5 years (IQR = 15.5)] and 9 in the control group [3 females, 44.0 years (IQR = 6.0)]. According to ROME IV criteria, 55% of patients were diagnosed with constipation. PAC-SYM faecal symptoms domain was reduced after 2 months of PDX supplementation (P = .004). We also observed a significant reduction in the PAC-QoL-concerns domain (P = .02). The average values for PAC-SYM and patient assessment of constipation quality of lifewere reduced significantly after intervention with PDX. There were no significant changes after the intervention period concerning biochemical variables, food intake, and inflammation markers. No adverse effects were observed during the supplementation period. CONCLUSIONS: The results of the present study suggest that short-term PDX supplementation may have favourable results on intestinal function and the quality of life of chronic kidney disease patients in HD.

Effects of propolis on inflammation markers in patients undergoing hemodialysis: A randomized, double-blind controlled clinical trial.

BACKGROUND AND AIMS: Several studies have been performed in vitro and in animals showing that propolis (a resin made by bees) has excellent anti-inflammatory properties, but no study has been performed in patients with chronic kidney disease (CKD) on hemodialysis (HD). The present study aimed to evaluate the effects of propolis supplementation on inflammatory markers in patients with CKD on HD. METHODS: This is a longitudinal, double-blind, placebo-controlled trial with patients randomized into two groups: propolis (4 capsules of 100 mg/day containing concentrated and standardized dry EPP-AF® green propolis extract) or placebo (4 capsules of 100 mg/day containing microcrystalline cellulose, magnesium stearate and colloidal silicon dioxide) for two months. Routine parameters were analyzed using commercial kits. The plasma levels of inflammatory cytokines were evaluated by flow luminometry. RESULTS: Forty-one patients completed the follow-up, 21 patients in the propolis group (45 ± 12 years, 13 women, BMI, 22.8 ± 3.7 kg/m2) and 20 in the placebo group (45.5 ± 14 years, 13 women, BMI, 24.8 ± 6.8 kg/m2). The obtained data revealed that the intervention with propolis significantly reduced the serum levels of tumour necrosis factor α (TNFα) (p = 0.009) as well as had the tendency to reduce the levels of macrophage inflammatory protein-1ß (MIP-1ß) (p = 0.07). There were no significant differences in the placebo group. CONCLUSION: Short-term EPP-AF® propolis dry extract 400 mg/day supplementation seems to mitigate inflammation, reducing the plasma levels of TNFα and MIP-1ß in patients with CKD on HD. This study was registered at clinicaltrials.gov (NCT04411758).

Polyphenol-rich açaí seed extract exhibits reno-protective and anti-fibrotic activities in renal tubular cells and mice with kidney failure.

The main goal of this study was to evaluate the reno-protective effects of a phenolic-rich Açaí seed extract (ASE) in mice with kidney failure. Kidney failure was induced chemically with an adenine-rich diet (0.25% w/w for 4 weeks) in male CD1 Swiss mice. Mice were then provided daily with ASE (at a dose of ~ 350 mg/kg/day) in drinking water for 4 weeks. Adenine mice exhibited renal dysfunction evidenced by increased proteinuria, increased uremia, extensive tubular atrophy and kidney fibrosis associated with overexpression of pro-fibrotic genes (collagen 1a1, transforming growth factor ß1, TGF-ß1) and markers of tubular injury (such as Kidney injury molecule-1, KIM-1). ASE was able to beneficially counteract all these effects. ASE improved oxidative damage and fibrosis by decreasing carbonylated protein and MDA concentrations, as well as collagen deposition in renal tissue. ASE decreased the expression of TGF-ß1 gene and the abundance of protein TGF-ß1 in kidneys. It further decreased both expression and urinary excretion of tubular injury biomarkers, e.g., KIM-1 and Neutrophil gelatinase-associated lipocalin. CKD ASE-treated mice exhibited higher polyphenol content and total antioxidant capacity compared to control mice. ASE further prevented the expression of profibrotic genes in HK2 human tubular cells exposed to uremic toxins. Taken together, these findings suggest that ASE exerted potent reno-protective and anti-fibrotic effects through its antioxidant activity and the modulation of the TGF-ß1 pathway.

Consumption of oils and anthocyanins may positively modulate PPAR-γ expression in chronic noncommunicable diseases: A systematic review.

Peroxisome proliferator-activated receptor-gamma (PPAR-γ) plays a central role in health and is an essential cardioprotective factor because of its effect on lipid and glucose metabolism, inflammation, and oxidative stress. We hypothesized that nutritional strategies positively regulate PPAR-γ expression in patients with noncommunicable diseases (NCDs). A systematic search was conducted using PubMed, Scientific Electronic Library Online (SciELO), and LILACS databases from May 2020 to January 2021. Eligibility criteria included placebo-controlled randomized clinical trials in adults with chronic diseases involving nutritional strategies, which performed PPAR-γ analysis (majority on mononuclear cells) before and after the intervention. The exclusion criteria included studies published more than 10 years ago, studies not published in English or Spanish, theses, reviews, and other study designs. The review was developed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Methodological quality was assessed based on 7 criteria obtained from the Cochrane Handbook. A total of 7 studies were included that reported the effects of different nutritional strategies (such as anthocyanins, fish oil, Berberis vulgaris juice, ketogenic diet, flaxseed oil, olive oil) on 346 patients with NCDs (such as type 2 diabetes, hypertension, obesity, and cancer) between 18 and 85 years of age. These results suggest that anthocyanins, flaxseed oil, and olive oil may function as putative PPAR-γ agonists.

Effect of cranberry supplementation on toxins produced by the gut microbiota in chronic kidney disease patients: A pilot randomized placebo-controlled trial.

BACKGROUND & AIMS: Patients with Chronic Kidney Disease (CKD) have an imbalance in the gut microbiota that can lead to increase levels of lipopolysaccharides (LPS) and uremic toxins such as indoxyl sulfate (IS), p-cresyl sulfate (p-CS), and indole-3 acetic acid (IAA). Among the therapeutic options for modulating gut microbiota are the bioactive compounds such as polyphenols present in cranberry, fruit with potential antioxidant and anti-inflammatory effects. This clinical trial focuses on evaluating the effects of supplementation with a dry extract of cranberry on plasma levels of LPS and uremic toxins in non-dialysis CKD patients. METHODS: It was a randomized, double-blind, placebo-controlled study. Patients were randomized into two groups: the cranberry group received 500 mg of dry cranberry extract (2 times daily), and the placebo group received 500 mg of corn starch (2 times daily) for two months. LPS plasma levels were evaluated by enzyme-linked immunosorbent assay (ELISA) and uremic toxins (IS, p-CS, and IAA) by high-performance liquid chromatography-fluorescence detection. Anthropometric measurements and food intake using the 24-h food recall technique were also evaluated before and after the intervention. RESULTS: Twenty-five participants completed two months of supplementation: 12 patients in the cranberry group (8 women, 56.7 ± 7.5 years, estimated glomerular filtration rate (eGFR) of 39.2 ± 21.9 mL/min); 13 patients in the placebo group (9 women, 58.8 ± 5.1 years, eGFR of 39.7 ± 12.9 mL/min). As expected, there was a negative association between glomerular filtration rate and p-CS and IS plasma levels at the baseline. No change was observed in the uremic toxins and LPS levels. CONCLUSION: Cranberry dry extract supplementation for two months did not reduce the LPS and uremic toxins plasma levels produced by the gut microbiota in non-dialysis CKD patients.

Is there an association between the plasma levels of uremic toxins from gut microbiota and anemia in patients on hemodialysis?

BACKGROUND: Anemia is one of the most frequent complications in patients with chronic kidney disease (CKD). Despite being multifactorial, the relative or absolute deficiency of erythropoietin production is the leading cause. Recent studies have shown that uremic toxins produced by the gut microbiota also may play a role in the genesis of anemia in these patients. OBJECTIVE: To evaluate the possible association between uremic toxins plasma levels and anemia in patients with CKD on hemodialysis (HD). METHODS: This cross-sectional study evaluated one hundred fifty-four patients (53.2% men, 51.2 ± 11.2 years, hemoglobin (Hb) levels of 11.2 ± 1.6 g/dL). Biochemical variables such as urea, creatinine, hemoglobin, hematocrit, were measured according to standard methods and uremic toxins such as indoxyl sulfate (IS), indole-3-acetic acid (IAA), p-cresyl sulfate (p-CS) plasma levels were measured by reverse-phase high-performance liquid chromatography (RP-HPLC). RESULTS: The levels of uremic toxins such as IS, IAA, p-CS were increased in all patients. However, no correlation was found between uremic toxins plasma levels and anemia parameters. Only patients with Hb < 11 g/dL presented a negative correlation between hematocrit and IAA plasma levels. CONCLUSION: There is no strong evidence that uremic toxins produced by the gut microbiota may be associated with anemia in patients with CKD on HD.

Uremic toxins levels from the gut microbiota seem not to be altered by physical exercise in hemodialysis patients.

PURPOSE: Regular physical exercise may result in many benefits to patients with chronic kidney disease (CKD) on hemodialysis (HD), including gut microbiota modulation and solute removal. The study aimed to evaluate the effects of two programs of intradialytic exercises on uremic toxins plasma levels in HD patients. METHODS: In experiment 1, twenty HD patients [12 men, 44.1 ± 8.9 years, BMI of 23.4 ± 2.4 kg/m2] were randomized into two groups: Aerobic exercise group (AEG, n = 11) that performed aerobic exercise on an adapted exercise bike three times a week for three months (36 sessions) and Control group (CG, n = 9). In experiment 2, twenty-six HD patients [19 men, 47.6 ± 11.0 years, BMI of 25.9 ± 3.6 kg/m2] were randomized into Resistance exercise group (REG, n = 14) that performed a resistance exercise program (using elastic bands and ankle cuffs with both lower limbs) monitored three times a week, during six months (72 sessions) and CG (n = 12). P-cresyl sulfate (p-CS), indoxyl sulfate (IS), and indol-3-acetic acid (IAA) plasma levels were determined by high-performance liquid chromatography (HPLC) with fluorescent detection. RESULTS: The uremic toxins plasma levels did not reduce in both exercise programs, aerobic exercise (IS: 32.7 ± 14.0 vs 33.0 ± 15.4 mg/L, p = 0.86; p-CS: 59.9 ± 39.3 vs 60.0 ± 41.2 mg/L, p = 0.99; IAA: 2233 [1488-2848] vs 2227 [1275-2824] µg/L, p = 0.72) and resistance exercise (IS: 28.3 ± 11.3 vs 29.1 ± 9.7 mg/L, p = 0.77; p-CS: 31.4 ± 21.3 vs 34.2 ± 19.8 mg/L, p = 0.63; IAA: 1628 [1330-3530] vs 2000 [971-3085] µg/L, p = 0.35) in HD patients. CONCLUSION: According to our findings, physical exercise does not appear to alter the levels of uremic toxins produced by the gut microbiota in HD patients.

Zinc Plasma Status and Sensory Perception in Nondialysis Chronic Kidney Disease Patients.

OBJECTIVE: The aim of this study was to evaluate the association between zinc plasma levels and sensory perception in patients with chronic kidney disease (CKD). METHODS: A cross-sectional study with 21 nondialysis CKD patients (11 men, 51.1 ± 7.1 years, body mass index 27.9 ± 7.1 kg/m2, estimated glomerular filtration rate 32.7 ± 19.9 mL/min) and 22 non-CKD volunteers (10 men, 49.8 ± 8.3 years, body mass index 28.5 ± 5.4 kg/m2) was conducted. Blood samples were collected to obtain plasma for zinc analysis. Anthropometric and biochemical parameters, as well as food intake and salivary flow rate, were also evaluated. Taste sensory perception for sweet, acidic, bitter, and salty flavors was determined by the "three-drop method," with 4 concentrations of the 4 basic tastes. RESULTS: As expected, zinc plasma levels were significantly lower in CKD patients (70.1 ± 19.2ug/dL) when compared with the control group participants (123.2 ± 24.6 µg dL) (P ˂ .0001). The bitter taste perception was lower in the CKD group (p˂0.0001). Our findings showed that sensitivity to sour (P = .047), salty (P = .03), and bitter tastes was significantly lower in participants with lower zinc plasma levels. Also, bitter taste sensitivity was lower in participants with less zinc intake (P = .038). When grouping control subjects and CKD patients, significant correlations were observed between zinc plasma levels and the number of correct answers for bitter taste (r = 0.49, P = .001), number of correct answers for salty taste (r = 0.30, P = .048), and total score of correct answers (r = 0.30, P = .044). CONCLUSIONS: Reduced zinc plasma levels in nondialysis CKD patients may be associated with lower perception of bitter, sour, and salty tastes and strategies to restore these levels are crucial due many factors, including food preferences and intake.

Association between low muscle mass and survival in incurable cancer patients: A systematic review.

Current data suggest that low skeletal muscle mass provides prognostic information in patients with cancer and may even be considered a biomarker in research and clinical evaluations. The aim of this systematic review was to explore whether low muscle mass is associated with overall survival (OS) in patients with incurable cancer. A systematic search was conducted for published literature using PubMed/MEDLINE, Scopus, LILACS, and the Cochrane Library, with no restrictions on language or publication date, to examine whether low muscle mass is associated with OS in patients with incurable cancer. Eligible studies included low muscle mass evaluated using gold standard techniques (dual energy x-ray absorptiometry or computed tomography). The studies quality assessment was performed using the Newcastle-Ottawa Scale. Thirteen studies were included. The studies reported on 1959 patients between 54.3 (median) and 72.9 (mean) y of age; pancreatic cancer was the most common type of tumor. According to the survival curves and most of the multivariate analyses, there was no statistically significant association between loss of muscle mass and reduced OS. Four studies reported that overweight or obese patients with muscle mass depletion had significantly shorter OS. These results indicate that there is insufficient evidence to associate low muscle mass with OS in patients with incurable cancer. Further studies deploying other muscle measurement methods suggest that use of low muscle mass cutoff alone is still necessary in the pursuit of OS prediction in this population.

Resistant starch supplementation attenuates inflammation in hemodialysis patients: a pilot study.

PURPOSE: In chronic kidney disease (CKD) patients, dysbiosis is associated with inflammation and cardiovascular risk, so many nutritional strategies are being studied to reduce these complications. Resistant starch (RS) can be considered a prebiotic that promotes many benefits, including modulation of gut microbiota which is linked to immune-modulatory effects. The aim of this study was to evaluate the effects of RS supplementation on proinflammatory cytokines in CKD patients on hemodialysis (HD). METHODS: A double-blind, placebo-controlled, randomized trial was conducted with sixteen HD patients (55.3 ± 10.05 years, body mass index (BMI) 25.9 ± 5.42 kg/m2, 56% men, time on dialysis 38.9 ± 29.23 months). They were allocated to the RS group (16 g RS/day) or placebo group (manioc flour). The serum concentration of ten cytokines and growth factors was detected through a multiparametric immunoassay based on XMap-labeled magnetic microbeads (Luminex Corp, USA) before and after 4 weeks with RS supplementation. RESULTS: After RS supplementation, there was a reduction of Regulated upon Activation, Normal T-Cell Expressed and Secreted (p < 0.001), platelet-derived growth factor (two B subunits) (p = 0.014) and interferon-inducible protein 10 (IP-10) (p = 0.027). The other parameters did not change significantly. CONCLUSION: This preliminary result indicates that RS may contribute to a desirable profile of inflammatory markers in CKD patients.

Cranberries - potential benefits in patients with chronic kidney disease.

Patients with chronic kidney disease (CKD) present many complications that potentially could be linked to increased cardiovascular mortality such as inflammation, oxidative stress, cellular senescence and gut dysbiosis. There is growing evidence suggesting that nutritional strategies may reduce some of these complications. Clinical studies suggest that supplementation of cranberries may have beneficial effects on human health such as prevention of urinary tract infections. More recently, the anti-inflammatory and anti-oxidant effects as well as modulation of gut microbiota provided by cranberry phytochemicals have drawn more attention. A better understanding of possible effects and mechanisms of action of cranberry supplementation in humans could inform researchers about warranted future directions for clinical studies targeting these complications in CKD patients by applying nutritional strategies involving cranberry supplementation.

Aryl Hydrocarbon Receptor and Uremic Toxins from the Gut Microbiota in Chronic Kidney Disease Patients: Is There a Relationship between Them?

Recent studies have suggested that uremic toxins such as indoxyl sulfate (IS) and indole-3-acetic acid (IAA) from the metabolism of the gut microbiota may be involved in the inflammatory signaling pathway in chronic kidney disease (CKD) patients through the activation of the aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor. The objective of this study was to investigate the possible relationship between uremic toxins (IS and IAA) and AhR protein expression in CKD patients. A cross-sectional observational study involving 17 hemodialysis (HD) [11 men, 55.5 ± 11.7 years of age, 54.0 (25.5-136.0) months of HD, body mass index (BMI) of 25.8 ± 3.8 kg/m2] and 15 non-dialysis-dependent (NDD) CKD (8 men, 54.1 ± 18.2 years of age, glomerular filtration rate of 34.8 ± 21.0 mL/min/1.73 m2, BMI of 27.4 ± 5.0 kg/m2) patients was conducted. IS and IAA levels were measured by reversed-phase high-performance liquid chromatography, and the protein expression levels of AhR and nuclear factor κ B (NF-κB) were evaluated by a Western blot assay. There was no difference in the expression of either AhR or NF-κB in the patients, and as expected, uremic toxin levels were higher in HD patients than in NDD patients. In the overall analysis, AhR protein expression was positively associated with IAA plasma levels ( r = 0.4; p = 0.03) and NF-κB protein expression ( r = 0.62; p = 0.001). Although the role of AhR in inflammation and CVD in CKD patients is far from being completely understood, the association between IAA and AhR observed in this study suggests a possible role for uremic toxins in the cell signaling pathway involved in inflammation in CKD patients.

A possible link between polyunsaturated fatty acids and uremic toxins from the gut microbiota in hemodialysis patients: A hypothesis.

INTRODUCTION: Indoxyl sulfate (IS) and p-cresyl sulfate (p-CS) are albumin-bound uremic toxins that are difficult to remove by hemodialysis (HD). Human serum albumin (HSA) carries several compounds, including fatty acids that can bind to site II of HSA and represent competing ligands for uremic toxins. The aim of this study was to investigate the association between fatty acids and uremic toxin plasma levels in patients undergoing HD. METHODS: Thirty-three HD patients (51.5% male, 54.9 ± 10.2 years old, 44.63 ± 28.4 months on HD, albumin level of 3.8 ± 0.3 g/dL) were evaluated. The erythrocyte fatty acid content (saturated fatty acid [SFA], monounsaturated fatty acid [MUFA], and polyunsaturated fatty acid [PUFA]) was measured by gas chromatography, and total IS and p-CS plasma levels were measured by reversed-phase high-performance liquid chromatography. FINDINGS: The mean percentages of docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) + DHA and gamma-linolenic (GLA) acid in the erythrocyte membrane were 1.35% ± 0.74%, 1.85% ± 0.79%, and 0.33% ± 0.26%, respectively. The mean levels of IS and p-CS were 19.4 ± 11.9 mg/dL and 101.5 ± 57.2 mg/dL, respectively. There was no significant association between SFA and MUFA and IS and p-CS; however, a negative correlation was found between p-CS and specific PUFAs, and the association between GLA and p-CS levels was retained after adjusting for potential confounding variables (ß = -0.49, P = 0.007). DISCUSSION: Polyunsaturated fatty acids may contribute to the decrease in p-CS uremic toxin plasma levels in patients with chronic kidney disease undergoing HD.

Bioactive food and exercise in chronic kidney disease: Targeting the mitochondria.

Chronic kidney disease (CKD), which affects 10%-15% of the population, associates with a range of complications-such as cardiovascular disease, frailty, infections, muscle and bone disorders and premature ageing-that could be related to alterations of mitochondrial number, distribution, structure and function. As mitochondrial biogenesis, bioenergetics and the dynamic mitochondrial networks directly or indirectly regulate numerous intra- and extracellular functions, the mitochondria have emerged as an important target for interventions aiming at preventing or improving the treatment of complications in CKD. In this review, we discuss the possible role of bioactive food compounds and exercise in the modulation of the disturbed mitochondrial function in a uraemic milieu.

Is there a relationship between tryptophan dietary intake and plasma levels of indoxyl sulfate in chronic kidney disease patients on hemodialysis?

INTRODUCTION: Gut microbiota is involved in generation of uremic toxins in chronic kidney disease (CKD) patients on hemodialysis (HD), like indoxyl sulfate (IS) that is originated from tryptophan amino acid fermentation. OBJECTIVE: To evaluate the tryptophan intake by chronic renal failure patients on HD and its possible relationship with IS plasma levels. METHODS: Participated of the study 46 patients with CKD on HD regular program (56.5% men; 52.7 ± 10.3 years; 63 (32.2-118.2) months on HD; BMI 25.6 ± 4.9 kg/m2). The tryptophan intake was evaluated by a 24-hours dietary recall (R-24h) performed on 3 different days. Routine biochemical tests and anthropometric measurements were evaluated. IS plasma levels were determined by High Performance Liquid Chromatography (HPLC) with fluorescent detection and the interleukin-6 (IL-6) plasma levels by immunoenzymatic method (ELISA, Enzyme Linked Immunosorbent Assay). RESULTS: The average of tryptophan intake was according to recommendation, but IS plasma levels (35.0 ± 11.9 mg/L) were elevated, however according to the EUTox values for uremic individuals. There was no correlation between the tryptophan intake and IS plasma levels. However, there was positive correlation between protein intake and tryptophan and variables used to evaluate lean body mass, and moreover, IS levels were positively associated with IL-6 (r = 0.6: p = 0.01). CONCLUSION: The present study suggests that tryptophan dietary intake may not be a determinant factor to IS levels. However, it suggests that gut microbiota may play an important role in systemic inflammation in patients with CKD.

Is there a relationship between tryptophan dietary intake and plasma levels of indoxyl sulfate in chronic kidney disease patients on hemodialysis? / Há relação entre ingestão alimentar de triptofano e níveis plasmáticos de indoxil sulfato em pacientes renais crônicos em hemodiálise?

Abstract Introduction: Gut microbiota is involved in generation of uremic toxins in chronic kidney disease (CKD) patients on hemodialysis (HD), like indoxyl sulfate (IS) that is originated from tryptophan amino acid fermentation. Objective: To evaluate the tryptophan intake by chronic renal failure patients on HD and its possible relationship with IS plasma levels. Methods: Participated of the study 46 patients with CKD on HD regular program (56.5% men; 52.7 ± 10.3 years; 63 (32.2-118.2) months on HD; BMI 25.6 ± 4.9 kg/m2). The tryptophan intake was evaluated by a 24-hours dietary recall (R-24h) performed on 3 different days. Routine biochemical tests and anthropometric measurements were evaluated. IS plasma levels were determined by High Performance Liquid Chromatography (HPLC) with fluorescent detection and the interleukin-6 (IL-6) plasma levels by immunoenzymatic method (ELISA, Enzyme Linked Immunosorbent Assay). Results: The average of tryptophan intake was according to recommendation, but IS plasma levels (35.0 ± 11.9 mg/L) were elevated, however according to the EUTox values for uremic individuals. There was no correlation between the tryptophan intake and IS plasma levels. However, there was positive correlation between protein intake and tryptophan and variables used to evaluate lean body mass, and moreover, IS levels were positively associated with IL-6 (r = 0.6: p = 0.01). Conclusion: The present study suggests that tryptophan dietary intake may not be a determinant factor to IS levels. However, it suggests that gut microbiota may play an important role in systemic inflammation in patients with CKD.

Resumo Introdução: A microbiota intestinal está envolvida na geração de toxinas urêmicas presentes nos pacientes com doença renal crônica (DRC) em hemodiálise (HD) como indoxil sulfato (IS), formado a partir da fermentação do aminoácido triptofano. Objetivo: Avaliar a ingestão de triptofano alimentar pelos pacientes renais crônicos em HD e sua possível relação com os níveis plasmáticos de IS. Métodos: Participaram do estudo 46 pacientes com DRC em programa regular de HD (56,5% homens; 52,7 ± 10,3 anos; 63 (32,2-118,2) meses em HD; IMC 25,6 ± 4,9kg/m2. A ingestão de triptofano foi avaliada por meio do recordatório alimentar de 24 (R-24h) realizado em três diferentes dias. Exames bioquímicos de rotina, bem como a avaliação antropométrica foram avaliados. Os níveis plasmáticos de IS foram determinados por cromatografia líquida de alto desempenho (HPLC) com detecção fluorescente e as concentrações plasmáticas de interleucina-6 (IL-6) pelo método imunoenzimático (ELISA, Enzyme Linked Immunosorbent Assay). Resultados: A ingestão média de triptofano estava dentro do recomendado, já os níveis plasmáticos de IS (35,0 ± 11,9mg/L) estavam elevados, porém de acordo com os valores da EUTox para indivíduos urêmicos. Não houve correlação entre a ingestão de triptofano e os níveis plasmáticos de IS. Contudo, houve correlação positiva entre ingestão de proteína e triptofano e variáveis que avaliam massa magra e, além disso, os níveis IS foram positivamente associados com os de IL-6 (r = 0,6: p = 0,01). Conclusão: O presente estudo sugere que a ingestão alimentar de triptofano pode não ser um fator determinante dos níveis de IS. No entanto, sugere que o intestino pode ter importante papel na inflamação sistêmica presente nos pacientes com DRC.

Synbiotic supplementation promotes improvement of chronic diarrhea of unknown etiology in patient with chronic kidney disease and provides better outcomes in dialysis / La suplementación con simbióticos promueve la mejora de la diarrea crónica de etiología desconocida en pacientes con enfermedad renal crónica y ofrece mejores resultados en diálisis

Background: Chronic kidney disease (CKD) patients often have gastrointestinal symptoms which may result in malnutrition and a negative impact on their quality of life. Modulation of the gut microbiota can be a strategy to promote host health and homeostasis. Case report: The authors present a case of chronic diarrhea in a hemodialysis (HD) patient with an unknown etiology. After about one year and several failed interventions, synbiotic therapy was performed. The diarrhea episodes ceased after three months of daily supplementation and both biochemical and nutritional parameters improved. Synbyotic therapy promoted clinical benefits in this patient. Discussion: Therefore, this simple therapy may be a promising alternative in CKD and it should be tested in larger studies (AU)

Introducción: los pacientes con enfermedad renal crónica (ERC) a menudo tienen síntomas gastrointestinales que pueden provocar desnutrición y un impacto negativo en su calidad de vida. La modulación de la microbiota intestinal puede ser una estrategia para promover la salud del huésped y la homeostasis. Caso clínico: los autores presentan un caso de diarrea crónica de etiología desconocida en un paciente en hemodiálisis (HD). Después de varias intervenciones fallidas durante un año, se realizó el tratamiento simbiótico. Los episodios de diarrea cesaron después de tres meses de la suplementación diaria y ambos parámetros bioquímicos y nutricionales mejoraron. La terapia con simbióticos promovió beneficios clínicos para este paciente. Discusión: por lo tanto, esta sencilla terapia puede ser una alternativa prometedora en la ERC y debe ser probada en estudios más amplios (AU)

Fructose intake: is there an association with uric acid levels in nondialysis-dependent chronic kidney disease patients? / La ingesta de fructosa: ¿existe una asociación con los niveles de ácido úrico en pacientes con enfermedad renal crónica no dependiente de diálisis?

Introduction: Fructose intake has increased dramatically in consequence of the consumption of fructose-based sweetened foods and beverages. Research suggests that high fructose intake has a strong association with uric acid (UA) levels and worse prognosis of chronic kidney disease (CKD). Objective: The aim of this study was to investigate the influence of fructose intake on plasma UA levels in nondialysis- dependent CKD patients. Methods: Fifty-two patients on stages 3-5 (64.2 ± 9.6 years, 24 men, glomerular filtration rate of 30.5 ± 10.3ml/ min) were divided into two groups: high fructose intake (>50g/d, n=29, 61.7 ± 9.3years) and low fructose intake (<50g/d, n=23, 65.8 ± 9.7years). Blood samples were collected to determine lipid profile and plasma levels of UA, inflammatory (interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), C-reactive protein (CRP)) and cardiovascular markers (monocyte chemotactic protein-1 (MCP-1), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1)). The energy, protein and fructose intake was estimated using 3-day 24-hour food recall. Results: High fructose intake was observed in 55.8% of patients and the mean UA levels were 7.7 ± 1.3 and 6.2 ± 1.6mg/dl in patients with high and low fructose intake, respectively (p<0.05). According to the regression analysis, fructose intake was the only variable able to affect the AU levels (b=0.42, p=0.016) after adjustment for gender, BMI, energy and protein intake, cardiovascular markers and lipid profile. Conclusions: These findings support a potential role for fructose in hyperuricemia in these patients (AU)

Introducción: El consumo de fructosa ha aumentado dramáticamente en consecuencia del consumo de alimentos y bebidas azucaradas a base de fructosa. Pesquisas sugieren que el alto consumo de fructosa tiene una fuerte asociación con niveles de ácido úrico (AU) y empeora el pronóstico de la enfermedad renal crónica (ERC). Objetivo: El objetivo de este estudio fue investigar la influencia del consumo de fructosa en los niveles plasmáticos de ácido úrico en pacientes con ERC que no son dependiente de diálisis. Métodos: Cincuenta y dos pacientes en fases 3-5 (64,2±9,6 años, 24 hombres, tasa de filtración glomerular de 30,5±10,3ml/min) se dividieron en dos grupos: alto consumo de fructosa (>50g/día, n=29, 61,7± 9,3 años) y bajo consumo de fructosa (<50g/día, n=23, 65,8±9,7 años). Muestras de sangre fueron recogidas para determinación del perfil lipídico y niveles plasmáticos de AU, citocinas inflamatorias (interleucina-6 (IL-6), factor de necrosis tumoral-α (TNF-α), proteína C-reactiva (CRP)), y marcadores cardiovasculares (proteína quimiotáctica de monocitos-1 (MCP-1), molécula de adhesión intercelular- 1 (ICAM-1) y molécula de adhesión vascular-1 (VCAM-1)). El consumo de energía, proteína y fructosa fue estimulado utilizando 3 días de recordatorio alimentar de 24 horas. Resultados: El alto consumo de fructosa fue observado en el 55,8% de los pacientes y los niveles medios de AU fueron 7,7±1,3 y 6,2±1,6mg/dl en pacientes con alto y bajo consumo de fructosa, respectivamente (p<0,05). De acuerdo con el análisis de regresión, el consumo de fructosa fue la única variable capaz de afectar los niveles de AU (b=0,42, p=0,016) después del ajuste para el género, composición corporal, energía y proteína, marcadores cardiovasculares y el perfil lipídico. Conclusiones: Estos resultados apoyan un papel potencial de la fructosa ocasionando la hiperuricemia en estos pacientes (AU)