Sulforaphane Supplementation Did Not Modulate NRF2 and NF-kB mRNA Expressions in Hemodialysis Patients.

BACKGROUND: Patients with chronic kidney disease (CKD) have reduced expression of erythroid nuclear factor-related factor 2 (NRF2) and increased nuclear factor κB (NF-κB). "Food as medicine" has been proposed as an adjuvant therapeutic alternative in modulating these factors. No studies have investigated the effects of sulforaphane (SFN) in cruciferous vegetables on the expression of these genes in patients with CKD. OBJECTIVE: The study aimed to evaluate the effects of SFN on the expression of NRF2 and NF-κB in patients on hemodialysis (HD). DESIGN AND METHODS: A randomized, double-blind, crossover study was performed on 30 patients on regular HD. Fourteen patients were randomly allocated to the intervention group (1 sachet/day of 2.5 g containing 1% SFN extract with 0.5% myrosinase) and 16 patients to the placebo group (1 sachet/day of 2.5 g containing corn starch colored with chlorophyll) for 2 months. After a washout period of 2 months, the groups were switched. NRF2 and NF-κB mRNA expression was evaluated by real-time quantitative polymerase chain reaction, and tumor necrosis factor alpha and interleukin-6 levels were quantified by enzyme-linked immunosorbent assay. Malondialdehyde was evaluated as a marker of lipid peroxidation. RESULTS: Twenty-five patients (17 women, 55 [interquartile range = 19] years and 55 [interquartile range = 74] months on HD) completed the study. There was no significant difference concerning the expression of mRNA NRF2 (P = .915) and mRNA NF-κB (P = .806) after supplementation with SFN. There was no difference in pro-inflammatory and oxidative stress biomarkers. CONCLUSION: 150 µmol of SFN for 2 months had no antioxidant and anti-inflammatory effect in patients with CKD undergoing HD.

Dark chocolate (70% cocoa) attenuates the inflammatory marker TNF-α in patients on hemodialysis.

BACKGROUND: Inflammation and oxidative stress lead to a high risk of cardiovascular disease in patients with chronic kidney disease (CKD). Food rich in polyphenols such as dark chocolate may be an effective strategy to mitigate inflammation and delay CKD complications, outwith sensorial pleasure promotion. The aim of this study was to evaluate the effects of dark chocolate on inflammation and oxidative stress markers in patients with CKD on hemodialysis (HD). METHODS: A clinical trial was carried out with 59 patients who were allocated into the chocolate group [40g of dark chocolate (70% cocoa) offered during HD sessions, 3×/week] or the control group with any intervention for two months. Plasma levels of the inflammatory cytokines TNF-α and IL-6 were evaluated by the ELISA method. Thiobarbituric acid reactive substances such as malondialdehyde (MDA) and LDLox levels were evaluated as lipid peroxidation markers. Routine biochemical parameters were analysed using commercial BioClin® kits. RESULTS: Thirty-five patients completed the chocolate group (18 men, 53.0 (16) years and 31.0 (39) months on HD) and 11 in the control group (7 men, 48.0 (17.5) years and 44.0 (56.5) months on HD). Regarding the differences between the groups, the patients who received dark chocolate had reduced plasma levels of TNF-α compared to the control (p = 0.008). No significant changes were observed in the oxidative stress parameters evaluated in both groups. Routine biochemical (including phosphorus and potassium levels) and anthropometric parameters and food intake were not changed after the study period. CONCLUSION: The intervention with dark chocolate (70% cocoa) for two months reduced the plasma levels of TNF-α in patients with CKD on HD. In addition, it is essential to emphasise that chocolate intake did not increase the plasma levels of phosphorus and potassium in these patients. This study was registered at clinicaltrials.gov as NCT04600258.

Curcumin supplementation improves oxidative stress and inflammation biomarkers in patients undergoing hemodialysis: a secondary analysis of a randomized controlled trial.

BACKGROUND AND OBJECTIVES: Recent studies have shed light on the potential role of curcumin in mitigating inflammation in patients with chronic kidney disease (CKD). This study aimed to evaluate the effects of curcumin supplementation on plasma levels of markers of inflammation and oxidative stress in patients with CKD undergoing hemodialysis (HD). METHODS: These are secondary exploratory analyses from a previous double-blind, randomized controlled pilot study registered under ClinicalTrials.gov Identifier no. NCT00123456. It included 28 hemodialysis patients from a previous study divided into two groups: curcumin group (receiving juice with 2.5 g of turmeric 3×/week for 12 weeks) and a control group. The TNF-α, IL-6 and Ox-LDL plasma levels were measured by sandwich enzyme immunoassays ELISA; lipid peroxidation was measured by the reaction between malondialdehyde (MDA) and thiobarbituric acid. RESULTS: After 12 weeks of supplementation with curcumin, the TNF-α plasma levels were significantly reduced [from 15.0 (8.23-73.3) to 6.17 (1.11-55.0) pg/mL, p = 0.01]. CONCLUSION: 12 weeks of treatment with curcumin in HD patients resulted in a reduction in the biomarker of inflammation (TNF-α), confirming our previous hypothesis that curcumin has an anti-inflammatory effect.

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.

Could resistant starch supplementation improve inflammatory and oxidative stress biomarkers and uremic toxins levels in hemodialysis patients? A pilot randomized controlled trial.

An imbalance of gut microbiota is considered a new cardiovascular risk factor for chronic kidney disease (CKD) patients, since it is directly associated with increased uremic toxin production, inflammation and oxidative stress. Strategies such as prebiotic supplementation have been suggested to mitigate these complications. We hypothesized that prebiotic-resistant starch could ameliorate uremic toxins levels, oxidative stress, and inflammatory states in hemodialysis (HD) patients. This pilot study evaluated 31 HD patients assigned to either resistant starch (16 g of resistant starch Hi-Maize® 260) or placebo (manioc flour) supplementation, which they received for 4 weeks on alternate days through cookies on dialysis days and powder in a sachet on non-dialysis days. Levels of interleukin (IL)-6, high-sensitive C-reactive protein, thiobarbituric acid reactive substances plasma (TBARS), protein carbonylation, indoxyl sulfate (IS) and p-cresyl sulfate were measured. Anthropometric and biochemical parameters, as well as, food intake were also evaluated. As expected, resistant starch group increased fiber intake (p > 0.01), in addition the prebiotic supplementation reduced IL-6 (p = 0.01), TBARS (p > 0.01), and IS (p > 0.01) plasma levels. No significant differences were evident in the placebo group. Prebiotic-resistant starch supplementation seems to be a promising nutritional strategy to improve inflammation, oxidative stress and to reduce IS plasma levels in CKD patients on HD.