Resistant Starch Type-2 Supplementation Does Not Decrease Trimethylamine N-Oxide (TMAO) Plasma Level in Hemodialysis Patients.

Dysbiosis is recognized as a new cardiovascular disease (CVD) risk factor in hemodialysis (HD) patients because it is linked to increased generation in the gut of uremic toxins such as trimethylamine N-Oxide (TMAO) from dietary precursors (choline, betaine, or L-carnitine). Nutritional strategies have been proposed to modulate the gut microbiota and reduce the production of these toxins. This study aimed to evaluate the effect of amylose-resistant starch (RS) supplementation on TMAO plasma levels in HD patients.We conducted a randomized, double-blind, placebo-controlled trial (NCT02706808) with patients undergoing HD enrolled in a previous pilot study. The participants were allocated to RS or placebo groups to receive 16 g/d of RS or placebo for 4 weeks. Plasma TMAO, choline, and betaine levels were measured with LC-MS/MS. Fecal microbiome composition was evaluated by 16S ribosomal RNA sequencing, followed by a search for TMA-associated taxa. Anthropometric, routine biochemical parameters, and food intake were evaluated.Twenty-five participants finished the study, 13 in the RS group, and 12 in the placebo group. RS supplementation did not reduce TMAO plasma levels. Moreover, no significant alterations were observed in choline, betaine, anthropometric, biochemical parameters, or food intake in both groups. Likewise, RS was not found to exert any influence on the proportion of potential TMA-producing bacterial taxa in fecal matter.RS supplementation did not influence plasma TMAO, choline, betaine, or fecal taxa potentially linked to TMAO. Thus, RS does not seem to modify the TMA-associated bacterial taxa, precursors of TMAO.Supplemental data for this article is available online at https://doi.org/10.1080/07315724.2021.1967814 .

Impact of curcumin supplementation on expression of inflammatory transcription factors in hemodialysis patients: A pilot randomized, double-blind, controlled study.

BACKGROUND & AIMS: Chronic kidney disease (CKD) patients have numerous complications associated with inflammation, which is a potential driver for cardiovascular disease. Curcumin, a compound of the curcuminoid class produced by the Curcuma longa, has been reported to activate nuclear factor erythroid factor 2-related (Nrf2) and inhibit nuclear factor kappa-B (NF-kB). Our aim was to evaluate the effects of curcumin juice on the expression of inflammatory transcription factors in hemodialysis (HD) patients. METHODS AND RESULTS: This double-blind randomized pilot study included 31 HD patients divided into two groups: curcumin group (receiving 100 mL of orange juice with 12 g of carrot and 2.5 g of turmeric after each dialysis session/week for 3 months) and control group (receiving the same juice without curcumin); 14 patients in each arm completed the study. The mRNA expression of Nrf2, NF-kB, NLRP3 inflammasome and IL-1ß in peripheral blood mononuclear cells (PBMC; using real-time quantitative polymerase chain reaction, qPCR) and routine biochemistries, food intake and anthropometrics were analyzed. After three months of supplementation, the curcumin group showed a significant decrease in NF-kB mRNA expression (AU) [from 1.08 (0.77-1.38) to 0.52 (0.32-0.95),p = 0.02] and in plasma high sensitivity C-reactive protein (hsCRP) levels [from 3.8 (2.5-6.8) to 2.0 (1.1-3.8) mg/L, p = 0.04]. There was no change in the other evaluated markers. CONCLUSION: Three months treatment with curcumin in CKD patients undergoing HD resulted in decreased markers of inflammation, NF-kB mRNA expression and hsCRP, suggesting that oral supplementation of curcumin may have an anti-inflammatory effect in this patient group. TRIAL REGISTRATION: Approved by the Ethics Committee of the Faculty of Medicine/UFF, number: 2.346.933. This study was registered within ClinicalTrials.gov under the number NCT03475017.

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.