Search

Background: Cadmium (Cd), a highly toxic heavy metal from agricultural activities, and its exposure can lead to impaired renal function by increasing reactive oxygen species. The atemoya fruit is known for its high phenolic and antioxidant compounds. This study aimed to evaluate the effects of atemoya extracts on renal function, oxidative stress parameters, and inflammatory biomarkers in a cadmium-induced nephrotoxicity model. Methods: Three aqueous extracts were prepared from different parts of the atemoya fruit: seeds, peel, and pulp. Twenty-five male Wistar rats were allocated into four groups: control, seed, peel, and pulp extracts at 2 g/kg for 25 days. All treatment groups administered intraperitoneal injections of cadmium chloride (CdCl2) (2 mg/kg) to induce renal damage. Results: The cadmium-treated groups showed decreased creatinine clearance, SOD, CAT, and GPx activities (p < 0.05) and increased serum levels of TNF-α and IL-6 compared to the control group (p < 0.05). The treatment with seed, peel, and pulp extracts increased creatinine clearance (p < 0.05), increased SOD, CAT, and GPx activities (p < 0.05), and reduced serum levels of TNF-α and IL-6 compared to the Cd group (p < 0.05). Conclusions: This study supports the use of atemoya as a promising candidate for mitigating nephrotoxicity and highlights the importance of its antioxidant and anti-inflammatory properties in renal health.

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.

The gut microbiota performs several crucial roles in a holobiont with its host, including immune regulation, nutrient absorption, synthesis, and defense against external pathogens, significantly influencing host physiology. Disruption of the gut microbiota has been linked to various chronic conditions, including cardiovascular, kidney, liver, respiratory, and intestinal diseases. Studying how animals adapt their gut microbiota across their life course at different life stages and under the dynamics of extreme environmental conditions can provide valuable insights from the natural world into how the microbiota modulates host biology, with a view to translating these into treatments or preventative measures for human diseases. By modulating the gut microbiota, opportunities to address many complications associated with chronic diseases appear. Such a biomimetic approach holds promise for exploring new strategies in healthcare and disease management.

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.

Cinnamon, a member of the Lauraceae family, has been widely used as a spice and traditional herbal medicine for centuries and has shown beneficial effects in cardiovascular disease, obesity, and diabetes. However, its effectiveness as a therapeutic intervention for chronic kidney disease (CKD) remains unproven. The bioactive compounds within cinnamon, such as cinnamaldehyde, cinnamic acid, and cinnamate, can mitigate oxidative stress, inflammation, hyperglycemia, gut dysbiosis, and dyslipidemia, which are common complications in patients with CKD. In this narrative review, we assess the mechanisms by which cinnamon may alleviate complications observed in CKD and the possible role of this spice as an additional nutritional strategy for this patient group.

Residual kidney function for patients with chronic kidney disease (CKD) is associated with better quality of life and outcome; thus, strategies should be implemented to preserve kidney function. Among the multiple causes that promote kidney damage, gut dysbiosis due to increased uremic toxin production and endotoxemia need attention. Several strategies have been proposed to modulate the gut microbiota in these patients, and diet has gained increasing attention in recent years since it is the primary driver of gut dysbiosis. In addition, medications and faecal transplantation may be valid strategies. Modifying gut microbiota composition may mitigate chronic kidney damage and preserve residual kidney function. Although various studies have shown the influential role of diet in modulating gut microbiota composition, the effects of this modulation on residual kidney function remain limited. This review discusses the role of gut microbiota metabolism on residual kidney function and vice versa and how we could preserve the residual kidney function by modulating the gut microbiota balance.

Vitamin K and vitamin K-dependent proteins have been reported to be associated with a large spectrum of age-related diseases. While most of these associations have been deduced from observational studies, solid evidence for the direct impact of vitamin K on cellular senescence remains to be proven. As vitamin K status reflects the complexity of interactions between dietary intake, gut microbiome activity and health, we will demonstrate the pivotal role of the diet-microbiome-health axis in human ageing and exemplify how vitamin K is implicated therein. We propose that food quality (i.e., food pattern) should be highlighted beyond the quantity of total vitamin K intake. Instead of focusing on a single nutrient, exploring a healthy diet containing vitamin K may be more strategic. As such, healthy eating patterns can be used to make dietary recommendations for the public. Emerging evidence suggests that dietary vitamin K is a modulator of the diet-microbiome-health axis, and this needs to be incorporated into the investigation of the impact of vitamin K on gut microbial composition and metabolic activities, along with host health outcomes. In addition, we highlight several critical caveats that need to be acknowledged regarding the interplay between diet, vitamin K, gut microbiome and host health that is pivotal for elucidating the role of vitamin K in ageing and responding to the urgent call of healthy eating concerning public health.

Abstract Imbalanced nutrition is associated with accelerated ageing, possibly mediated by microbiota. An analysis of the circulatory microbiota obtained from the leukocytes of participants in the MRC Twenty-07 general population cohort was performed. We now report that in this cohort, the most biologically aged exhibit a significantly higher abundance of circulatory pathogenic bacteria, including Neisseria, Rothia and Porphyromonas, while those less biologically aged possess more circulatory salutogenic (defined as being supportive of human health and wellbeing) bacteria, including Lactobacillus, Lachnospiraceae UCG-004 and Kocuria. The presence of these salutogenic bactreria is consistent with a capacity to metabolise and produce Nrf2 agonists. We also demonstrate that associated one carbon metabolism, notably betaine levels, did not vary with chronological age, but displayed a difference with socioeconomic position (SEP). Those at lower SEP possessed significantly lower betaine levels indicative of a poorer diet and poorer health span and consistent with reduced global DNA methylation levels in this group. Our data suggest a clear route to improving age related health and resilience based on dietary modulation of the microbiota.

Abstract This nutrition consensus document is the first to coordinate the efforts of three professional organizations - the Brazilian Association of Nutrition (Asbran), the Brazilian Society of Nephrology (SBN), and the Brazilian Society of Parenteral and Enteral Nutrition (Braspen/SBNPE) - to select terminology and international standardized tools used in nutrition care. Its purpose is to improve the training delivered to nutritionists working with adult patients with chronic kidney disease (CKD). Eleven questions were developed concerning patient screening, care, and nutrition outcome management. The recommendations set out in this document were developed based on international guidelines and papers published in electronic databases such as PubMed, EMBASE(tm), CINHAL, Web of Science, and Cochrane. From a list of internationally standardized terms, twenty nutritionists selected the ones they deemed relevant in clinical practice involving outpatients with CKD. The content validity index (CVI) was calculated with 80% agreement in the answers. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework was used to assess the strength of evidence and recommendations. A total of 107 terms related to Nutrition Assessment and Reassessment, 28 to Diagnosis, nine to Intervention, and 94 to Monitoring and Evaluation were selected. The list of selected terms and identified tools will be used in the development of training programs and the implementation of standardized nutrition terminology for nutritionists working with patients with chronic kidney disease in Brazil.

Probiotics may mitigate the generation of uremic toxins and inflammatory biomarkers. The aim of this study was to evaluate the effects of probiotics on uremic toxins and inflammatory biomarkers in CKD. In this randomized, double-blind, placebo-controlled trial, 30 patients (63.8 ± 7.5 years, 14 men, mean BMI of 27.2 ± 3.8 kg/m2) were assigned to receive one of two treatments: probiotics (n = 15; Streptococcus thermophilus, Lactobacillus acidophilus and Bifidobacteria longum-90 billion CFU per day) or placebo (n = 15) daily for three months. Plasma uremic toxins were measured using reversed-phase liquid-chromatography (RP-HPLC); choline, betaine and trimethylamine-N-oxide (TMAO) were measured using liquid chromatography–mass spectrometry (LC-MS/MS); and inflammatory biomarkers were measured using ELISA. Uremic toxins were not influenced by the probiotics; however, IL-6 levels increased significantly from 15.6 (14.8–20.8) pg/mL to 23.0 (17.6–29.6) pg/mL, p = 0.01. There was a positive correlation between the levels of p-cresyl sulfate and urea (r = 0.55; p = 0.02) and between TMAO and CRP (r = 0.46; p = 0.05) at baseline. These data suggest that probiotic supplementation did not result in expected benefits for non-dialysis CKD patients.

Many studies have been conducted to identify therapeutic strategies to modulate inflammation and oxidative stress, complications that contribute to the increased morbidity and cardiovascular mortality in patients with chronic kidney disease (CKD). Among several non-pharmacological strategies, the use of bioactive compounds has emerged as a potential approach to reduce these complications in CKD patients. In this context, turmeric/curcumin may have positive consequences in terms of cardiovascular and nephroprotection because of its antibacterial, antiviral, anti-inflammatory and anti-oxidative effects. The aim of this review is to discuss the role of curcumin as a nutritional strategy to reduce cardiovascular risk factors as inflammation and oxidative stress in CKD patients.

Objectives: The aim was investigate resveratrol, grape juice, or red wine effects on FNDC5 and UCP2 gene expression on muscle and adipose tissue of Wistar rats receiving a high-fat diet. Methods: Five groups of female Wistar rats formed with five animals in each (Control Group-CG, High-Fat Group-HFG-20%, Grape Juice Group-GJG; Red Wine Group-RWG and Resveratrol Group-RG) were treated for 2 months. At the end, adipose and muscle tissues were collected, FNDC5 and UCP2 mRNA expressions were obtained by using real-time polymerase chain reaction. Irisin levels were assessed through ELISA. For comparison: two way ANOVA, using Duncan as post-test. Results: FNDC5 mRNA expression was increased in RG and GJG muscle (p

Hemodialysis (HD) majorly represents the global treatment option for patients with chronic kidney disease stage 5, and, despite advances in dialysis technology, these patients face a high risk of morbidity and mortality from malnutrition. We aimed to provide a novel view that malnutrition susceptibility in the global HD community is either or both of iatrogenic and of non-iatrogenic origins. This categorization of malnutrition origin clearly describes the role of each factor in contributing to malnutrition. Low dialysis adequacy resulting in uremia and metabolic acidosis and dialysis membranes and techniques, which incur greater amino-acid losses, are identified modifiable iatrogenic factors of malnutrition. Dietary inadequacy as per suboptimal energy and protein intakes due to poor appetite status, low diet quality, high diet monotony index, and/or psychosocial and financial barriers are modifiable non-iatrogenic factors implicated in malnutrition in these patients. These factors should be included in a comprehensive nutritional assessment for malnutrition risk. Leveraging the point of origin of malnutrition in dialysis patients is crucial for healthcare practitioners to enable personalized patient care, as well as determine country-specific malnutrition treatment strategies.

ABSTRACT Proton pump inhibitors (PPIs) bind to enzyme H+/K+-ATPase and inhibit its activity in the stomach, thus decreasing the secretion of gastric acid. PPIs may trigger acute interstitial nephritis, a potentially severe adverse event commonly associated with acute kidney injury. Studies have found that prolonged use of PPIs may increase the risk of chronic kidney disease (CKD). The increase in prescription and inadequate use of this class of medication calls for studies on the effects of prolonged PPI therapy on renal function. Therefore, this review aimed to analyze recent studies on the matter and discuss the possible consequences of the long-term use of PPIs on renal function.

ABSTRACT Introduction: Chronic Kidney disease (CKD) patients have a high prevalence of cardiovascular mortality, and among the risk factors are dyslipidemia and obesity, common findings in the early stages of CKD. The aim of this study was to evaluate the effects of low protein diet (LPD) on the lipid and anthropometric profile in non-dialysis CKD patients. Methods: Forty CKD patients were studied (20 men, 62.7 ± 15.2 years, glomerular filtration rate (GFR) 26.16 ± 9.4 mL/min/1.73m2). LPD (0.6g/kg/d) was prescribed for six months and, biochemical and anthropometric parameters like body mass index (BMI), waist circumference and body fat mass (assessed by dual X-ray absorptiometry - DXA) were evaluated before and after six months with LPD. Results: After six months of nutritional intervention, patients presented reduction on BMI (from 28.1 ± 5.6 to 27.0 ± 5.3 Kg/m2, p = 0.001), total cholesterol (from 199.7 ± 57.1 to 176.0 ± 43.6mg/dL, p = 0.0001), LDL (from 116.2 ± 48.1 to 97.4 ± 39.1 mg/dL, p = 0,001) and uric acid (from 6.8 ± 1.4 to 6.2 ± 1.3 mg/dL, p = 0.004). In addition, GFR values were increased from 26.2 ± 9.5 to 28.9 ± 12.7mL/min (p = 0.02). The energy, proteins, cholesterol and fiber intake were reduced significantly. Conclusion: LPD prescribe to non-dialysis CKD patients for six months was able to improve some cardiovascular risk factors as overweight and plasma lipid profile, suggesting that LPD can be also an important tool for protection against cardiovascular diseases in these patients.

ABSTRACT Background: Irisin is a recently identified exercise-induced hormone that stimulates the "browning" of the white adipose tissue, at least in mice. In chronic kidney disease (CKD) patients, irisin regulation is not fully understood, and little attention has been given to the effects of exercise on irisin levels in these patients. The purpose of this study was to assess the effects of high intensity exercise on irisin plasma levels in CKD patients under hemodialysis (HD). Methods: Fifteen HD patients (5 men, 44.4 ± 15.1 years old) were studied and served as their own controls. High intensity (single session) intradialytic strength exercises consisted of three sets of ten repetitions with four different movements in both lower limbs during 30 minutes. Blood samples were collected on different days (exercise and non-exercise day) at exactly the same time (30 and 60 minutes after the start of dialysis session). Plasma irisin levels were measured by ELISA assay and anthropometric and biochemical parameters were evaluated. Results: Irisin plasma levels were significantly reduced in both exercise day (125.0 ± 18.5 to 117.4 ± 15.0 ng/mL, p=0.02) and non-exercise day (121.5 ± 13.7 to 115.4 ± 17.2 ng/mL, p=0.02) after 60 minutes of dialysis. Conclusion: These data suggest that intense intradialytic strength exercise was unable to increase the circulating concentration of irisin in HD patients. Moreover, our data show that after one hour of dialysis session, irisin plasma levels may be reduced.

Resumo Introdução: A suplementação de ferro é uma das importantes recomendações em pacientes com doença renal crônica (DRC), contudo, uma sobrecarga desse mineral pode contribuir para o estresse oxidativo, condição essa bastante relacionada com o risco cardiovascular nesses pacientes. Objetivo: O objetivo desse trabalho foi investigar se os níveis de ferritina estão associados ao estresse oxidativo avaliado pelo malondialdeído (MDA) em pacientes em hemodiálise (HD). Métodos: Vinte pacientes em tratamento de HD (55,0 ± 15,2 anos, tempo de diálise de 76,5 ± 46,3 meses, IMC 23,6 ± 3,0 kg/m2) foram comparados com 11 indivíduos saudáveis (50,9 ± 8,0 anos, IMC 23,8 ± 1,9 kg/m2). O nível de MDA foi medido pela reação com o ácido tiobarbitúrico e os dados bioquímicos de rotina foram obtidos por meio do prontuário médico. Resultados: Os pacientes em HD apresentaram elevados níveis de MDA (13,2 ± 5,3 nmol/mL) quando comparados aos indivíduos saudáveis (5,1 ± 2,7 nmol/mL; p < 0,01). Doze pacientes (60%) apresentaram valores de ferritina superiores a 500 ng/mL e houve correlação positiva entre ferritina e MDA nos pacientes HD (r = 0,66; p = 0,005; n = 17). Conclusão: O excesso dos estoques de ferro em pacientes em HD resulta em um aumento da peroxidação lipídica e, consequentemente, contribui para um maior estresse oxidativo nesses pacientes.

Background: Oxidative stress and inflammation are common findings in chronic kidney disease (CKD) patients, and they are directly related to the increased risk of developing cardiovascular disease, which is the major cause of death in these patients, particularly for those undergoing hemodialysis (HD). Strength physical exercise is a new therapeutic approach to reduce these complications in CKD patients. Following this, the purpose of this study was to assess the effect of acute intradialytic strength physical exercise on oxidative stress and inflammatory responses in HD patients. Methods: Sixteen HD patients were studied (11 women; 44.4±14.6 years; body mass index 23.3±4.9 kg/m2; 61.6±43.1 months of dialysis) and served as their own controls. Acute (single session) intradialytic physical exercise were performed at 60% of the one-repetition maximum test for three sets of 10 repetitions for four exercise categories in both lower limbs during 30 minutes. Blood samples were collected on two different days at exactly the same time (30 minutes and 60 minutes after initiating the dialysis—with and without exercise). Antioxidant enzymes activity [superoxide dismutase (SOD), catalase, and glutathione peroxidase], lipid peroxidation marker levels (malondialdehyde), and inflammatory marker levels (high-sensitivity C-reactive protein) were determined. Results: SOD plasma levels were significantly reduced after acute physical exercise from 244.8±40.7 U/mL to 222.4±28.9 U/mL (P=0.03) and, by contrast, increased on the day without exercise (218.2±26.5 U/mL to 239.4±38.6 U/mL, P=0.02). There was no alteration in plasma catalase, glutathione peroxidase, malondialdehyde, or high-sensitivity C-reactive protein levels in on either day (with or without exercise). Additionally, there was no association between these markers and clinical, anthropometric, or biochemical parameters. Conclusion: These data suggest that acute intradialytic strength physical exercise was unable to reduce oxidative stress and inflammation, and in addition, it seems to reduce plasma SOD levels, which could exacerbate the oxidative stress in HD patients.

Introduction: Polyphenols contained in natural sources such as grapes, have been considered pharmacological agents to combat oxidative stress and inflammation, common features in Chronic Kidney Disease patients. Objective: To evaluate the effects of grape powder supplementation on inflammatory and antioxidant biomarkers in hemodialysis (HD) patients. Methods: The double-blind placebo-controlled randomized clinical trial evaluated non-diabetic HD patients that received grape powder (500 mg of polyphenols/day) (n = 16, 9 men, 53.0 ± 9.8 years of age, 111.6 ± 58.2 HD months) or placebo (n = 16, 9 men, 52.7 ± 13.7 years of age, 110.4 ± 93.1 HD months) for five weeks. The glutathione peroxidase (GSH-Px) activity and C-reactive protein (CRP) levels were evaluated by ELISA method. Results: After the intervention period, the patients receiving grape powder showed an increase in the GSH-Px activity (16.5 (41.0) to 42.0 (43.3) nmol/min/ml) (p < 0.05) and they did not have the CRP levels increased as seen in placebo group (2.6 (0.28) to 2.8 (0.23 mg/L) (p < 0.05). Conclusion: The use of grape powder as phenolic source could play an important role as an antioxidant and anti-inflammatory agent in non-diabetic HD patients.

Introduction: Patients with chronic kidney disease present selenium (Se) plasma deficiency which is an essential trace element with important biological functions and, the best known biological role is attributed to its presence in the antioxidant enzyme, glutathione peroxidase (GPx). The Se content of foods depends on soil and some authors have suggested that Amazon soil (North Brazilian region) has high Se concentrations when compared to other regions of Brazil. Objective: The objective of this work was to compare the Se status in hemodialysis (HD) patients from North and Southeast of Brazil. Methods: Thirty-eight patients from Southeast region (22 men and 16 women, 15% diabetic, 53.5 ± 26.4 yrs) were compared to 40 patients from North region (28 men and 12 women, 22.5% diabetic, 63.5 ± 11.9 yrs). Se in plasma was determined through atomic absorption spectrophotometry with hydride generation. Results: The plasma Se levels in patients from Southeast region were significantly lower (17.5 ± 11.9 μg/L) when compared to patients from the North (37.1 ± 15.8 μg/L) (p < 0.001). However, both patient groups presented low Se plasma levels when compared to recommended values (60- 120 μg/L). There was no correlation between plasma Se levels and analyzed parameters. Conclusion: We concluded that patients from North (Amazon) region present higher plasma Se levels when compared to the patients from Southeast of Brazil. However, independently of the region, HD patients presented Se deficiency.

Cardiovascular diseases are a major public health problem. Different risk factors have been recognized as the main causes of the development and progression of cardiovascular diseases. Flaxseed is a source of dietary fiber, lignans, and alpha-linolenic acid. The aim of this study was to evaluate the effects of prolonged supplementation with flaxseed flour as preventive therapy on cardiovascular risk parameters in healthy Wistar rats. Material and Methods: Female Wistar rats were divided into two groups after giving birth and during lactation period: the control group was fed with diet based on casein and the flaxseed group was fed with diet based on casein containing 25% of flaxseed flour. At weaning, 10 male offspring from each group continued to receive the same diets from their mothers during 250 days. The body weight, visceral fat mass, cholesterol, triglycerides, HDL, VLDL, glucose and thickness of the aorta were analyzed. Results: The body weight, visceral fat mass, cholesterol, triglycerides, HDL, VLDL, glucose and thickness of the aorta values were statistically lower when compared to control group. Conclusion: The data suggest that flaxseed flour supplementation in healthy wistar rats for a prolonged period may decrease the thickness of the aorta and may be used as a preventive measure in modulating some modifiable risk factors related to cardiovascular disease.

Gut microbiota imbalance is common in patients with chronic kidney disease (CKD) and associates with factors such as increased circulating levels of gut-derived uremic toxins, inflammation, and oxidative stress, which are linked to cardiovascular disease and increased morbimortality. Different nutritional strategies have been proposed to modulate gut microbiota, and could potentially be used to reduce dysbiosis in CKD. Nutrients like proteins, fibers, probiotics, and synbiotics are important determinants of the composition of gut microbiota and specific bioactive compounds such as polyphenols present in nuts, berries. and fruits, and curcumin, may also play a key role in this regard. However, so far, there are few studies on dietary components influencing the gut microbiota in CKD, and it is therefore not possible to conclude which nutrients should be prioritized in the diet of patients with CKD. In this review, we discuss some nutrients, diet patterns and bioactive compounds that may be involved in the modulation of gut microbiota in CKD and provide the background and rationale for studies exploring whether nutritional interventions with these dietary components could be used to alleviate the gut dysbiosis in patients with CKD.

INTRODUÇÃO E OBJETIVOS: Pacientes com doença renal crônica (DRC) apresentam um quadro de anorexia que pode estar relacionado com o processo inflamatório crônico, característico desta população. Assim, o presente estudo teve como objetivo avaliar se há associação entre inflamação e o hormônio orexígeno, acyl-grelina, em pacientes com DRC em hemodiálise (HD). MÉTODOS: Foram estudados 36 pacientes (61,1% homens; 46,7 ± 14,9 anos; IMC 22,9 ± 3,9 kg/m²) em programa regular de HD (65,0 ± 46,8 meses em HD). Os níveis plasmáticos de acyl-grelina e dos marcadores inflamatórios (TNF-α, IL-6 e PCR) foram medidos com o uso do método imunoenzimático (ELISA, Enzyme Linked Immunosorbent Assay). Dados antropométricos foram coletados para avaliação do estado nutricional e a ingestão alimentar foi analisada por meio de recordatório alimentar de 24h de 2 dias. RESULTADOS: Os pacientes apresentaram elevados níveis de IL-6 (83 ± 10 pg/mL), TNF-α (21,06 pg/mL [20,6-40,0]) e PCR (2,7 pg/mL [1,7-3,4]) quando comparados a valores normais. Os níveis plasmáticos de acyl-grelina (18,0 pg/mL [1,3-77,7 pg/mL]) foram baixos comparados com valores de indivíduos saudáveis. Porém, pacientes com elevado IMC (> 25 kg/m²) apresentaram menores concentrações plasmáticas de acyl-grelina (13,6 [1,3-30,5] pg/mL) em relação aos pacientes com IMC < 25 kg/m² (21,7 [7,4-77,7] pg/mL (p < 0,05). Houve correlação negativa entre o IMC e acyl-grelina (r = -0,38; p = 0,02), porém, não houve correlação significativa entre acyl-grelina e os marcadores inflamatórios. CONCLUSÃO: Apesar dos pacientes em HD apresentarem baixas concentrações de acyl-grelina e uma provável resistência a este hormônio, não houve associação entre inflamação e acyl-grelina.

Dentro do conceito de que os hormônios são regulados por um ciclo de reciprocidade, o fato de osteoblastos e adipócitos serem desenvolvidos a partir de células-tronco mesenquimais e da remodelação óssea ser regulada pela leptina, traz a ideia de possíveis participações do osso no metabolismo energético e vice-versa. Estudos recentes têm demonstrado que a diferenciação e as funções das células ósseas são reguladas pela leptina, que parece desencadear uma resposta bimodal central, via sistema nervoso simpático, e uma local, na qual a leptina agiria sobre o osso. De fato, estudos têm revelado complexa interação entre osso, tecido adiposo e cérebro; no entanto, existem poucos estudos sobre esse crosstalk em pacientes com doença renal crônica (DRC). Como tais pacientes têm tendência à diminuição da densidade mineral óssea e elevados níveis de leptina, o presente artigo apresentou uma revisão sobre o possível envolvimento entre tecido adiposo e massa óssea, em pacientes com DRC.

Previous studies have indicated selenium (Se) deficiency in hemodialysis (HD) patients and it may increase the mortality risk for death among hemodialysis patients. Studies from our laboratory showed poor nutritional status of Se in HD patients. The purpose of this study was to evaluate Se levels as predictors of cardiovascular mortality in HD patients. A total of 44 HD patients (53.0±15.0 years old, average time on dialysis 80.1±112.7 months, BMI, 24.6±34.3 kg/m2) from the RenalCor Clinic in Rio de Janeiro, Brazil, were followed up 36 months. The plasma and erythrocyte Se levels were determined by atomic absorption spectrophotometry with hydride generation (Hitachi, Z−500). Associations between Se levels and cardiovascular mortality in HD patients were examined by Cox's regression model. Mean plasma Se was 72.1±70.1 μg/L and erythrocyte Se 194.8±148.91 μg/L and a total of 17 patients died from cardiovascular event during the follow-up period. Analysis by the Cox model showed that only low erythrocyte Se levels were significant predictors of mortality (hazard ratio [HR] 0.995 [95% CI 0.991-0.999]. In conclusion, decreased erythrocyte Se level may increase the risk of death in hemodialysis patients.

Low protein diet for patients with chronic kidney disease (CKD) during conservative treatment (CT) aims to reduce the progression and symptoms of the CKD. This study aimed to evaluate the glomerular filtration rate (GFR) in patients receiving low protein diet during 3 years (≅ 4 clinic visits per year). The study comprised 321 patients with CKD on CT from a Renal Nutrition Ambulatory of a Federal Lagoa Hospital. All patients received dietary prescription according to NKF-K/DOQI recommendations and the diet adherence was evaluated with patients being asked whether they were adhering to the treatment and through reported dietary intake (2 weekdays and 1 weekend day). Patients were divided in 4 groups: diabetes Mellitus (DM) patients who adhered (G1) and not adhered to the diet (G2), and patients without DM who adhered (G3) and not adhered to the diet (G4). Groups Before After Group 1-DM (n=83) Cr (mg/dL) 1.9 ± 0.6 1.6 ± 0.7* GFR (mL/min) 37.8 ± 14.4 46.6 ± 17.3** Group 2-DM (n=106) Cr (mg/dL) 1.9 ± 0.7 2.03 ± 0.7 GFR (mL/min) 43.8 ± 17.3 42.6 ± 13.3 Group 3-non-DM (n=75) Cr (mg/dL) 2.2 ± 0.8 1.8± 0.8* GFR (mL/min) 34.3 ± 13.1 40.9 ± 21.7 Group 4-non-DM (n=57) Cr (mg/dL) 2.2 ± 0.8 2.4 ± 1.0 GFR (mL/min) 39.9 ± 19.0 35.2 ± 18.4 There was no difference between diabetic and non-diabetic patients who adhered to the diet. Both groups showed improvement on GFR. In conclusion, these analyses suggest that a lower protein intake retards the progression of renal disease.

Hemodialysis patients (HD) present inflammation, metabolic acidosis and anorexia which contribute to loss of functional capacity, muscle mass and strength. Resistance training (RT) is recognized to reduce these effects on the musculoskeletal system. This study aimed to evaluate the effects of intradialytic RT on the functional capacity, strength and muscle mass in HD patients. Eighteen HD patients (50% men, 49.3±11.5 years, BMI 22.7±3.9 kg/m2, 63.2±46.3 months on dialysis) exercised 3 times a week for 6 months. All parameters were evaluated before and after 6 months of RT. There were significant changes in the functional tests 10-TSS (10 times Sit-to-Stand Test) and SS-60 (amount of sit to stand in 60 seconds), in the muscle mass and % of body fat after RT. The medial and proximal leg circumferences increased significantly and no differences were observed in torque extensor and flexor and distal leg circumferences. In conclusion, RT contributes to improving body composition and functional capacity of HD patients. Parameters Before RT After RT 10-TSS (seconds) 27.9±6.4 21.9±4.1* SS-60 (repetitions) 26.0±6.7 28.9±5.7* Muscle mass - men (kg) 48.0±9.1 51.5±10* Muscle mass - women (kg) 34.1±4.4 36.9±4.9* Body fat - men (%) 29.2±5.1 25.3±5.1* Body fat - women (%) 34.6±5.1 32.4±4.7* LG- Proximal -R (cm) 53.6±6.6 55.4±6.7* LG- Proximal -L (cm) 52.7±5.8 54.1±6.7 LG- Medial -R (cm) 46.8±5.1 48.6±4.9* LG- Medial -L (cm) 46.6±4.4 48.5±5.4* LG- Leg circumference; R-right; L- left; ⁎ p

Dietary intake of selenium (Se) plays an important role as an antioxidant and anti-inflammatory agent due to its antioxidant properties and the richest known food source of Se is the Brazilian nut, found in the Amazon region, Brazil. The aim of this study was to evaluate the effect of the Brazilian nut supplementation on oxidative stress and inflammation markers and lipid stratus in HD patients. Forty HD patients (57.5% men, 53.3±16.1yrs) were studied and received 1 nut (around 5g) a day for three months. The GSH-Px, 8-isoprostane, 8-OHdG, TNF-α and IL-6 levels were determined by ELISA before and after supplementation. The LDL-c and HDL-c levels were determined by enzymatic colorimetric method using the specific kit. After 3 months supplementation, cytokines, 8-OHdG, 8-isoprostane levels decreased and the activity of GSH-Px increased significantly. Besides, after supplementation, the HDL levels increased and LDL levels decreased significantly. Parameters Before supplementation After supplementation GSH-Px (nmol/mL/min) 34.06±5.2 40.3±8.4⁎ 8-isoprostane (pg/mL) 12.2±4.5 6.6±4.6* 8-OHdG (pg/mL) 214.5(1.0−1042.0) 18.7 (1.0−78.8)* IL-6 (pg/mL) 67.1 (21.1−80.2) 13.5 (12.8−22.2)* TNF-α (pg/mL) 21.0±0.3 13.9±8.7* HDL (mg/dL) 39.0±14.2 44.7± 4.8* LDL (mg/dL) 86.0±28.7 74.7±29.5* ⁎ p

Exercise programs have been recommended as nutritional interventions in hemodialysis (HD) patients to minimize loss of muscle mass, improve physical and functional capacity, inflammation thus controlling or preventing cardiovascular diseases (CVD), which accounts for 50% of mortality in dialysis patients. Therefore the purpose of this study was to analyze the effects of a resistance exercise (RE) program on biochemical parameters, inflammation markers, and body composition in HD patients. Thirty- six HD patients (61.1% men, mean age 46.7±2.5yrs) were studied. The anthropometric and biochemical parameters are presented in Table. There were significant differences after 6 months of RE in albumin and CRP plasma levels and body composition parameters. The HD patients gained nearly 3kg of lean mass and lost about 3% of body fat. Parameters Before(n=30) After(n=30) BMI (kg/m2) 22.8±4.0 23.3±4.3 Arm muscular area (cm) 30.3±13.7 35.4±13.8* Body Fat (%) 31.5±5.6 28.4±5.9* Lean mass (kg) 42.4±10.0 45.5±11.0* Albumin (g/dL) 3.6±0.3 3.8±0.2* Globulin (g/dL) 3.2±0.3 2.8±0.5** Interleukin-6 (pg/mL) 81.3±9.4 78.7±10.4 TNF-α (pg/mL) 25.7±6.5 24.3±8.7 Creatinine (mg/dL) 12.5±3.6 12.2±3.7 CRP (pg/mL) 2.9±0.4 2.0±0.1* ⁎ p

Polyphenols and antioxidants anti-inflammatory have been considered pharmacological agents to combat oxidative stress in chronic diseases due the reduction in the formation of free radicals (FR). Hemodialysis (HD) patients have an imbalance between oxidant and antioxidant activity, with increased levels of FR and consequently an increase of lipid peroxidation, thereby raising the risk for cardiovascular disease (CVD). The beneficial health effects of grape juice or red wine for these patients have been attributed to the antioxidant activity of its polyphenols. Then, this study aimed to evaluate the effects of grape powder supplementation on inflammation and glutathione peroxidase levels in hemodialysis (HD) patients. Thirty-two HD patients from CIN, RJ, Brazil were studied and randomly into two groups: placebo group- PG (16 patients, 9 men, 52.7 ± 13.7 yrs) and experimental group EG (16 patients, 9 men, 53.0 ± 9.8 yrs). Each patient received 12g/day of powder grape with grape jelly or only grape jelly (placebo) during 5 weeks. The lipid profile, C-reactive protein (CRP) levels and glutathione peroxidase (GPx) activity were evaluated before and after supplementation (Table). The data suggest that the consumption of grape powder was effective to increase the activity of GPx and decreasing the progression the inflammation. Thus, our results indicate that grape powder plays an important role as an antioxidant agent in HD patients. Placebo Group Experimental Group Before After Before After CRP (mg/mL) 2.6±0.2 2.8±0.2* 2.6±0.2 2.6±0.2 LDL-C 86.3±38.8 94.4±34.3 80.5±25.0 82.9±22.1 Total cholesterol 154.6±44.9 163.3±44.8 143.9±29.2 145.4±28.3 GPx (U/g prot) 17.5±9.8 29.1±30.7 19.7±20.3 41.0±27.7* ⁎ p

Nutritional status is a major determinant of the outcome of hemodialysis (HD) patients. While protein wasting is associated with morbidity and mortality, high fat mass and central adiposity is also observed in HD population and, related to metabolic disorders. Therefore, body composition assessment is a key point to provide adequate nutritional care to these patients. In this way, practical and reliable indicators of body composition are needed for clinical purposes. Thus, the objective of this study was to evaluate the use of anthropometry as an alternative to dual energy X-ray absorptiometry (DXA), considered the reference method to evaluate body fat in HD patients. Thirty-nine HD patients (52.7±11.3 years, 24 men, BMI, 23.7±4.0 kg/m2, urea clearance (Kt/Vsp) of 1.47±0.22 and 64.1±46.1 months on HD) were studied. Percentage of body fat (%BF) was performed by DXA scans (Prodigy Advanc Plus, Lunar Corp, Madison, WI, USA) and anthropometry (biceps, triceps, subscapular and suprailiac skinfold thicknesses) after a HD session. Body density was calculated using the formula of Durnin and Womersley (1974) and the %BF was calculated by Siri´s equation (Siri, 1961). The reference values for %BF were considered (Lohman et al., 1991). The mean of %BF assessed by anthopometry and DXA was 25.2±6.9% and 26.8±8.3% for men and 32.8±6.3% and 31.5±8.7% for women, respectively. The most of HD patients presented high %BF (≥25% for men and ≥32% for women): 59.0% by anthropometry and 56.4% by DXA. The paired analysis showed that the %BF assessment was not different when evaluated by anthropometry or DXA methods (p=0.6). The kappa coefficient between DXA and anthropometry was 0.42 (p

In chronic kidney disease (CKD) patients undergoing conservative low-protein diets ameliorate uremic symptoms and certain CKD complications and, can slow progression of renal disease. The aim of this study was to determine the short-term effects of protein restriction on the progression of CKD. Twenty-six CKD patients from the Renal Nutrition Ambulatory, Nutrition Faculty, UFF, Niterói, Brazil (63.1±13.7 years, 13 men, and % body fat for men, 25.0±6.9% and for women, 36.0±3.3%) were analysed. All patients were originally prescribed low-protein diets and energy according to NKF-K/DOQI recommendations. One month later, their body mass index, creatinine, urea and creatinine clearance (calculated by Cockcroft-Gault) were evaluated (Table). The patients reported good adherence diet in clinical records. In spite of the short period of time, the dietary protein restriction during conservative treatment seems slowing the progression of kidney disease. Parameters Before (n=26) After (n=26) BMI (kg/m2) 28.6±6.8 28.0±6.9* Creatinine (mg/dL) 2.1±0.8 2.0±0.9 CrCl (mL/min) 35.8±15.7 40.9±20.0* Urea (mg/dL) 85.5±29.4 77.4±32.3 ⁎ p

Elevated serum uric acid has been associated to a variety of cardiovascular disease states and with systemic inflammation. The aim of this study was to analyze the association between uric acid levels and inflammatory markers in hemodialysis (HD) patients. This cross-sectional study included 50 HD patients (62% men, 54.3±12.6 yrs, BMI 24.4±4 Kg/m2) and 21 healthy individuals (45% men, 50.7±15.7 yrs, BMI 25.5±4.0 Kg/m2). Uric acid was measured using uricase-PAP method, inflammatory (TNF-α, IL-6 and CRP) and atherosclerosis markers (ICAM-1, VCAM-1, MCP-1 and PAI-1) were measured by a multiplexed particle-based flow cytometric assay. There was a positive correlation between serum uric acid and inflammatory markers, IL-6 (r=0.30, p=0.01), CRP (r=0.37, p=0.003), TNF-α (r=0.40, p=0.001) and adhesion molecules levels, ICAM-1 (r=0.53, p=0.0001), and VCAM-1 (r=0.45, p=0.0001) Parameters HD Patients Healthy individuals CRP (mg/mL) 0.32 ± 0.30* 0.11 ± 0.12 TNF-α (pg/mL) 5.5 ± 2.1* 2.4 ± 1.1 IL-6 (pg/mL) 4.1 ± 1.6* 2.7 ± 0.4 PAI-1 (ng/mL) 7.0 ± 2.7 6.2 ± 2.1 MCP-1 (pg/ml) 47.6 ± 24.2 37.3 ± 19.0 VCAM-1 (ng/mL) 48.5 ± 8.5* 23.8 ± 5.5 ICAM-1 (ng/mL) 20.5 ± 15.9* 7.2 ± 1.2⁎p

Selenium (Se) is a well-known antioxidant with a critical role in the proper functioning of nervous and muscle functions. In the last decade, many authors have suggested that Se may be a potent protective agent for neurons and myocytes through selenoprotein expression in the brain, as well as in skeletal and cardiac muscles. Low Se status has been associated with reduced coordination, motor speed and muscle strength. Reduced muscle function is common in hemodialysis (HD) patients; however, no study evaluated the association between muscle function and Se levels in HD patients. The objective of this study was to correlate muscle function with Se plasma levels in HD patients. Twenty HD patients (12 men, 54.5±15.2 yr; 81.7±52.8 months on HD) from RenalCor Clinic at Rio de Janeiro, Brazil were studied. Blood samples were collected during fasting, before a regular HD session. The Se plasma levels were determined by atomic absorption spectrophotometry with hydride generation (Hitachi, Z-500) and handgrip strength (HGS) was measured three times with a mechanical dynamometer (Jamar) after HD sessions in the non-fistula side and the highest value was used for analysis. HGS values less than the 10th percentile of an age-, gender- and regional specific reference were considered as muscle function loss. Plasma Se levels (31.9±14.8 μg/L) were below the normal range (60-120 μg/L) and all patients were Se deficient. HGS values were significantly greater in males (31.0±11.5 kg vs 14.0±6.8 kg for females) (p=0.001) and the muscle function loss was observed in 50% of patients and, those with muscle function loss presented low Se levels (26.5±12.1 μg/L) when compared to patients with preserved muscle function (39.12±14.5 μg/L) (p=0.05). These data suggest that Se can have an important role on muscle function in HD patients. However, more research is needed to better understand this possible relationship in CKD patients.

Inflammation and oxidative stress are importante features associated with pathogenesis of cardiovascular disease in hemodialysis (HD) patients. Apelin is a bioactive peptide involved in a variety of physiological functions that has been associated with inflammation, however; little is known about apelin in chronic kidney disease (CKD). Thus, the purpose of this study was to analyse apelin plasma levels in HD patients and verify if there is any relationship with inflammation and oxidative markers. Twenty-four HD patients (53.6±14.4 years of age, 14 men and body mass index (BMI) of 25.0±4.2 kg/m2) were studied and compared to 15 healthy subjects (51.3±13.5 years of age, 7 men and BMI of 26.3±3.7 kg/m2). Plasma apelin-12 and -36 were measured using the enzyme immunometric assay (EIA) method. Plasma electronegative low density lipoprotein (LDL-) levels were measured using ELISA method. The levels of tumor-necrosis factor-α (TNF-α), interleukin-6, leptin and plasminogen activator inhibitor-1 were measured by a multiplex assay kit and C-reactive protein (CRP) by immunoturbidimetry. There was no difference between apelin-36 levels in HD patients (0.82±0.60 ng/mL) and healthy subjects (0.83±0.23 ng/mL). In contrast, apelin-12 levels were significantly higher in patients, 0.34 ±0.15 ng/mL than in healthy subjects, 0.24± 0.13ng/mL. Inflammation (TNF-α and CRP) and oxidative markers levels (LDL-) were higher in HD patients (5.4±1.3 pg/mL, 0.15 (0.33) mg/dL and 0.19±0.13U/L, respectively); however, there was not correlation among apelin-12 or -36 and inflammatory or oxidative markers. In conclusion, plasma apelin seems to be not associated with inflammatory and oxidative status in HD patients.

The inflammation is a common feature in HD patients and may contribute to muscle wasting. Handgrip strength (HGS) has been recognized as a useful tool in assessing muscle function in hemodialysis (HD) patients. The aim of this study was to evaluate the association between inflammation and muscle function in HD patients. Twenty-three HD patients (19 men, 54.3±12.4 years of age, BMI, 24.5±4.6kg/m2) were studied. HGS was measured 3x with a mechanical dynamometer after the HD sessions. HGS values less than the 10th percentile of an age-, gender- and regional specific reference were considered as muscle function loss. Tumoral necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels were determined by a multiplex assay kit through the device Luminex method. C-reactive protein (CRP) was measured with the immunoturbidimetric method. HGS values were significantly greater in males (28.8±9.7 kg) than females (13.9±6.5kg) (p 0.3mg/dL). CRP and IL-6 were not correlated with HGS, but TNF-α were inversely correlated with HGS (r =-0.42; p = 0.01). These data suggest that inflammation can play an important role on muscle function in HD patients.fx1

Resting energy expenditure (REE) is the predominant component of total daily energy expenditure (TEE). Metabolic disorders and comorbities, such as inflammation and diabetes, can affect the REE in hemodialysis (HD) patients. The objective of this study was to evaluate the relationship between inflammation and REE estimated by TEE in HD patients. Twenty-five HD patients (54.5±11.7 years, 15 men, BMI, 24.4±4.7 kg/m2, urea clearance (Kt/Vsp) of 1.43±0.26 and 58.2±42.7 months on HD) were studied. TEE was measured during two days (one dialysis and one fx1 nondialysis day) by SWA (SenseWear Pro2 Armband, BodyMedia Inc, Pittsburgh, PA, USA). This monitor provides directly the TEE and the physical active energy expenditure (PAEE); the REE measurement was obtained by the subtraction of PAEE and thermic effect of food (approximately 10% of TEE) from TEE. C-reactive protein (CRP) was measured by immunoturbidimetric method. The REE was 1677.7±273.5 kcal/d for men and 1267.0±221.6 kcal/d for women (p〈0.0001). The CRP levels values were 0.27 ± 0.26 mg/dL and nine patients (36%) had CRP 〉0.3 mg/dL, compatible with chronic inflammation. A trend for high REE was observed in patients with inflammation (1865±216 kcal/d for men with CRP≥0.3 mg/dL and 1584±257kcal/d with CRP〈0.3 mg/dL (p= 0.05); 1361.4±181.5 kcal/d for women with CRP≥0.3 mg/dL and 1204.1±238.2kcal/d with CRP〈0.3 mg/dL (p = 0.27). CRP was positively correlated with REE (r=0.41; p=0.04). In conclusion, chronic mild inflammation can increase the REE in HD patients.

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.

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.

ABSTRACT Introduction: Gut microbiota imbalance is linked to high uremic toxins production such as indole-3-acetic acid (IAA) in chronic kidney disease patients. This toxin can activate the aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor involved with inflammation. Strategies to restore gut microbiota balance can be associated with reduced production of IAA and its deleterious effects. This study aimed to evaluate prebiotic resistant starch (RS) supplementation effects on IAA plasma levels and AhR mRNA expression in CKD patients on hemodialysis (HD). Methods: This randomized, double-blind and placebo-controlled clinical trial evaluated forty-two stable HD patients allocated in RS (n=22) or placebo (n=20) groups. Patients received, alternately, cookies and sachets containing 16 g/day of RS (Hi-Maize 260®) or manioc flour for four weeks. Fasting pre-dialysis blood samples were collected and IAA plasma levels measured by high performance liquid chromatography. Peripheral blood mononuclear cells were isolated and processed for AhR and nuclear factor kappa B (NF-κB) mRNA expression analyzes by quantitative real-time PCR. Anthropometric and biochemical parameters, as well as food intake were also evaluated. Results: Thirty-one patients completed the study, 15 in the RS group and 16 in the placebo group. Although there was no significant alteration in IAA plasma levels, neither in AhR mRNA expression and NF-κB mRNA expression after RS supplementation, a positive correlation (r=0.48; p=0.03) was observed between IAA plasma levels and AhR expression at baseline. Conclusion: Even though prebiotic RS supplementation did not influence IAA levels or AhR expression, their positive association reinforces a possible interaction between them.

ABSTRACT Background: Patients with chronic kidney disease (CKD) present an imbalance of the gut microbiota composition, leading to increased production of uremic toxins like p-cresyl sulfate (PCS), product from bacterial fermentation of the amino acids tyrosine (Tyr) and phenylalanine (Phe) from the diet. Thus, diet may be a determinant in the uremic toxins levels produced by the gut microbiota. The aim of this study was to evaluate the possible relationship between Tyr and Phe intake and PCS plasma levels in non-dialysis CKD patients. Methods: Twenty-seven non-dialysis CKD patients (stages 3 and 4) without previous nutritional intervention were evaluated. The dietary intake was evaluated using a 24-hour recall, 3-day food record and protein intake was also estimated by Protein Nitrogen Appearance (PNA). The plasma levels of PCS were measured using reverse phase high performance liquid chromatography. Results: The evaluated patients (GRF, 34.8 ± 12.4 mL/min, 54.2 ± 14.3 years, BMI, 29.3 ± 6.1 kg/m2) presented mean protein intake of 1.1 ± 0.5 g/kg/day), Tyr of 4.5 ± 2.4 g/day and Phe of 4.6 ± 2.5 g/day. PCS plasma levels (20.4 ± 15.5 mg/L) were elevated and positively associated with both, Tyr (r = 0.58, p = 0.002) and Phe intake (r = 0.53, p = 0.005), even after adjustments for eGFR and age. Conclusion: This study suggests that the diet is an important modulator of the uremic toxins plasma levels produced by the gut microbiota, in non-dialysis CKD patients.

Abstract Background: Oxidative stress and inflammation are present in coronary artery disease (CAD) and are linked to the activation of the transcription nuclear factor kappa B (NF-κB). To attenuate these complications, transcription factors like nuclear factor erythroid 2-related factor 2 (Nrf2) and peroxisome proliferator-activated receptor-β/δ (PPARβ/δ) can be activated to inhibit NF-κB. However, the available data on expression of NF-κB, Nrf2 and PPARβ/δ in CAD patients are limited. Objective: To evaluate the expression of the transcription factors NF-κB and Nrf2 and PPAR��/�� in CAD patients. Methods: Thirty-five patients (17 men, mean age 62.4 ? 7.55 years) with CAD and twelve patients (5 men, mean age 63.50 ? 11.46 years) without CAD were enrolled. Peripheral blood mononuclear cells (PBMCs) were isolated and processed for mRNA expression of Nrf2, NF-κB, NADPH: quinone oxidoreductase 1 (NQO1) and PPARβ/δ mRNAs using quantitative real-time polymerase chain reaction (qPCR). p < 0.05 was considered statistically significant. Results: There was no difference in the mRNA expressions of Nrf2 (1.35 ? 0.57), NF-κB (1.08 ? 0.50) or in the antioxidant enzyme NQO1 (1.05 ? 0.88) in the CAD group compared to the group without CAD (1.16 ? 0.76, 0.95 ? 0.33, 0.81 ? 0.55, respectively). However, PPARβ/δ was highest expressed in the CAD group (1.17 ? 0.86 vs. 0.56 ? 0.34, p = 0.008). Conclusion: The main finding of this study was the PPARβ/δ being more expressed in the PBMC of patients with CAD compared to the control group, whereas no differences were observed in Nrf2 or NF-κB mRNA expressions.