Whey Protein, Vitamins C and E Decrease Interleukin-10 in Chronic Hemodialysis Patients: A Pioneer, Randomized, Double-Blind Pilot Trial.

OBJECTIVE: To evaluate the effects of supplementation with whey protein combined with vitamins C and E on inflammatory markers in hemodialysis (HD) patients. DESIGN AND METHODS: This was a pioneer, randomized and double-blinded study. Patients were randomized into two groups and stratified by HD frequency. The supplementation group received 20 g of whey protein, 250 mg of vitamin C, and 600 IU of vitamin E; the placebo group, 20 g of rice flour, and microcrystalline cellulose capsules. The interventions were given after HD, 3 times a week, for 8 weeks. The inflammatory markers were assessed: interleukin (IL) IL-12p70, IL-10, IL-6, IL-8, and tumor necrosis factor alpha. For statistical analysis, the χ2 test, Student's t-test, Mann-Whitney test, analysis of variance for repeated two-way measurements, paired t test, and Wilcoxon test were performed. P < .05 was considered statistically significant. RESULTS: Twenty-three patients completed the study. No significant differences were found in inflammatory markers when comparing the groups postintervention. In the intragroup was a decrease in IL-10 in the supplementation group after 8 weeks (P = .0382). IL-6 tended to decrease by 810.95% in the supplementation group and increased by 732.8% (nonsignificant) in the placebo group. CONCLUSION: Whey protein combined with vitamins C and E significantly reduced IL-10 in the supplementation group and could be beneficial to reduce IL-6 in HD patients. Future studies are suggested with a larger sample size, different supplementation doses, and longer interventions.

Effects of supplementation with vegetable sources of alpha-linolenic acid (ALA) on inflammatory markers and lipid profile in individuals with chronic kidney disease: A systematic review and meta-analysis.

BACKGROUND AND AIMS: Inflammation and dyslipidemia are traditional risk factors and well-known causes of morbidity and mortality in chronic kidney disease (CKD). Alpha-linolenic acid (ALA), an essential fatty acid mainly found in vegetable sources, has been associated with anti-inflammatory effects and improving lipid profile. This systematic review and meta-analysis investigate the effects of supplementation with vegetable sources of ALA on inflammatory marker and lipid profile in individuals with CKD. METHODS: This review included studies with adult or elderly patients with CKD, including those receiving dialysis, using oral supplementation or food or combined interventions containing vegetable sources of ALA. All studies were randomized trials and The Cochrane Collaboration's tool was use for assessing risk of bias. RESULTS: 19 studies provided data for meta-analyses. ALA had significant effect on reducing C-reactive protein (CRP) after supplementation (WMD: -1.32; 84.5% CI, -2.35 to -0.29, P = 0.012), on the other hand, had no significant effect on total cholesterol (WMD: -2.85; 90.1% CI, -14.43 to 8.73, P = 0.629), high density lipoprotein (WMD: 1.09; 92.4% CI, -1.82 to 3.99, P = 0.463), low density lipoprotein (WMD: -3.87; 86.7% CI, -12.62 to 4.89, P = 0.387) and triglycerides (WMD: -16.42; 87.7% CI, -47.83 to 14.98, P = 0.305). CONCLUSION: Vegetables sources of ALA showed beneficial effects on reducing inflammatory marker CRP in CKD patients but had no effect on lipid profile. Future well-designed studies are needed to investigate the effectiveness of vegetables sources of ALA, particularly in CKD.

Vitamin C decreases reduced glutathione in chronic haemodialysis patients: a pilot, randomised, double-blind trial.

PURPOSE: Whey protein has antioxidant properties through its amino acid cysteine, which enhances the biosynthesis of glutathione, the most abundant antioxidant non-protein in mammalians. Glutathione influences vitamin C recycling and increases its protective effect on oxidative stress (OS). The aim of this study was to analyse the effect of whey protein and vitamin C supplementation on OS biomarkers in chronic haemodialysis (HD) patients. METHODS: This pioneer trial was a randomised, double-blind, pilot study in patients from a dialysis clinic. Patients were randomised into three groups (1:1:1) and stratified by HD frequency (2 or 3 times/week). Sachets containing protein powder (20.0 g) with/without vitamin C (0.25 g) or placebo (20.0 g of white rice flour) with vitamin C (0.25 g) were supplemented after each HD session, 3 times/week for 8 weeks. Blood samples were collected at the baseline period and after 8 weeks for the measurement of reduced glutathione (GSH), oxidised glutathione (GSSG), the GSH:GSSG ratio, malondialdehyde, vitamin C, and glutathione peroxidase-1. RESULTS: Twenty-two patients were enrolled, of which 18 concluded the trial, 6 per group (18.2%, n = 4 losses during follow-up). The vitamin C group presented decreased GSH levels after supplementation (p = 0.053) and a decreasing tendency in the GSH:GSSG ratio (non-statistically significant), while MDA levels significantly decreased only in the whey protein-supplemented groups (p ≤ 0.05). CONCLUSION: The results suggest a pro-oxidant effect of 0.25 g of vitamin C alone in chronic HD patients. CLINICAL TRIAL REGISTRATION: https://ensaiosclinicos.gov.br/ , RBR-65b8f4.

Apple intake improves antioxidant parameters in hemodialysis patients without affecting serum potassium levels.

Oxidative stress (OS) is associated with increased morbidity and mortality in hemodialysis (HD) patients, and the consumption of fruits seems to improve OS due to their antioxidant properties. Therefore, we hypothesized that Fuji apple intake improves OS markers in HD patients due to its polyphenolic compounds without increasing serum potassium levels. This trial was a 1-group, pre- and posttest comparison between 16 patients who had been on hemodialysis for at least 3 months without any acute illness or hyperkalemia. Each volunteer consumed 2 Fuji apples (~360 g) per day for 1 week. Blood samples were collected at the baseline period and after 8 days for the measurement of total antioxidant status, ascorbic acid, catalase, glutathione peroxidase, superoxide dismutase, reduced glutathione, total oxidant status, oxidative stress index, potassium, phosphorus, uric acid, glucose, and fructosamine. For tolerance evaluation, participants were asked about their bowel habits. Apple intake increased glutathione peroxidase (P = .006) and superoxide dismutase activities (P = .006) and ascorbic acid levels (P = .002). No significant changes were observed in uric acid, potassium, phosphorus, glucose, and fructosamine levels. Additionally, there was a decrease in the catalase activity (P = .021) and in the total antioxidant status values (P = .004). However, increased total oxidant status (P = .003) and oxidative stress index (P = .033) levels were observed after apple intake. In conclusion, the intake of 2 Fuji apples per day for 1 week was well tolerated and improved antioxidant parameters in HD patients without affecting serum potassium levels.

Green tea extract reverses endothelial dysfunction and reduces atherosclerosis progression in homozygous knockout low-density lipoprotein receptor mice.

The aim of this study was to evaluate the effects of green tea extract (GTE) administration on vascular reactivity and atherosclerosis progression in low-density lipoprotein receptor knockout mice. We hypothesized that GTE intake may ameliorate atherosclerosis by improving endothelial dysfunction. Animals (n = 12 per group) were fed a hypercholesterolemic diet and received either water or GTE at a dose of 50, 100, or 300 mg/kg once a day by gavage (100 µL/10 g weight). After 4 weeks, atherosclerosis extension and vascular reactivity were evaluated in the aorta, and the levels of lipids, monocyte chemotactic protein-1 (MCP-1), and tumor necrosis factor α were measured in the plasma. Administration of GTE at a dose of 50 mg/kg significantly decreased the area of atherosclerotic lesions by 35%, improved the vascular reactivity in the isolated thoracic aorta, and lowered the plasma levels of both MCP-1 and triglycerides. Delivery of 100 mg/kg of GTE only promoted vasocontraction and vasorelaxation (P < .05), whereas a dose of 300 mg/kg was ineffective. Maximum contraction and relaxation negatively correlated with the lesion area (r = -0.755 and -0.767, respectively), whereas the plasma levels of MCP-1 and triglycerides positively correlated with plaque size (r = 0.549 and 0.421, respectively). In summary, our results supported the hypothesis that administration of GTE at low doses may contribute to a decrease in atherosclerosis progression by reversing endothelial dysfunction.

Association of mate tea (Ilex paraguariensis) intake and dietary intervention and effects on oxidative stress biomarkers of dyslipidemic subjects.

OBJECTIVE: To evaluate the effect of long-term ingestion of mate tea, with or without dietary intervention, on the markers of oxidative stress in dyslipidemic individuals. METHODS: Seventy-four dyslipidemic volunteers participated in this randomized clinical trial. Subjects were divided into three treatment groups: mate tea (MT), dietary intervention (DI), and mate tea with dietary intervention (MD). Biochemical and dietary variables were assessed at the beginning of the study (baseline) and after 20, 40, 60, and 90 d of treatment. Participants in the MT and MD groups consumed 1 L/d of mate tea. Those in the DI and MD groups were instructed to increase their intake of fruit, legumes and vegetables and decrease their consumption of foods rich in cholesterol and saturated and trans-fatty acids. Biomarkers of oxidative stress such as antioxidant capacity of serum (ferric reducing antioxidant potential assay), uric acid, reduced glutathione, paraoxonase-1 enzyme, lipid hydroperoxide (LOOH), and protein carbonyl were analyzed. RESULTS: Participants in the DI group showed a significant decrease in total fat and saturated fatty acid intakes. Those in the DI and MD groups presented a significant increase in vitamin C consumption. For all groups, there was a significant increase in ferric reducing antioxidant potential and reduced glutathione concentrations but no significant changes in LOOH, protein carbonyl, and paraoxonase-1 values. The reduced glutathione concentration was positively correlated with the consumption of monounsaturated fatty acids, fiber, and vitamin C, whereas levels of LOOH were inversely correlated with intakes of vitamin C and fiber. In addition, LOOH correlated positively with low-density lipoprotein cholesterol and inversely with high-density lipoprotein cholesterol, which had a positive association with paraoxonase-1. CONCLUSION: The ingestion of mate tea independently of the dietary intervention increased plasma and blood antioxidant protection in patients with dyslipidemia.

Mate tea (Ilex paraguariensis) improves glycemic and lipid profiles of type 2 diabetes and pre-diabetes individuals: a pilot study.

OBJECTIVES: Yerba mate (Ilex paraguariensis) infusions have been shown to reduce plasma glucose in animals and serum lipids in humans. The aim of this study was to evaluate the effects of roasted mate tea consumption, with or without dietary counseling, on the glycemic and lipid profiles of individuals with type 2 diabetes mellitus (T2DM) or pre-diabetes. METHODS: Twenty-nine T2DM and 29 pre-diabetes subjects were divided into 3 groups: mate tea, dietary intervention, and mate tea and dietary intervention. Individuals drank 330 mL of roasted mate tea 3 times a day and/or received nutritional counseling over 60 days. Blood samples were collected and food intake was assessed at baseline and after 20, 40, and 60 days of treatments. RESULTS: Mate tea consumption decreased significantly the levels of fasting glucose (25.0 mg/dL), glycated hemoglobin A(1c) (HbA(1c)) (0.85%), and low-density lipoprotein cholesterol (LDL-c) (13.5 mg/dL) of T2DM subjects (p < 0.05); however, it did not change the intake of total energy, protein, carbohydrate, cholesterol, and fiber. In pre-diabetes individuals, mate tea consumption combined with nutritional counseling diminished significantly the levels of LDL-c (11 mg/dL), non-high-density lipoprotein cholesterol (HDL-c) (21.5 mg/dL), and triglycerides (53.0 mg/dL) (p < 0.05). Individuals of this group decreased significantly their consumption of total fat (14%), cholesterol (28%), and saturated (23.8%) and monounsaturated (28.0%) fatty acids, and increased their fiber intake by 35% (p < 0.05). CONCLUSIONS: Mate tea consumption improved the glycemic control and lipid profile of T2DM subjects, and mate tea consumption combined with nutritional intervention was highly effective in decreasing serum lipid parameters of pre-diabetes individuals, which may reduce their risk of developing coronary disease.

Effect of ingestion of rice bran drink in rats subjected to forced swimming and elevated plus maze tests.

Bran cereals are known to contain substantial concentrations of important nutrients, bioactive compounds, fiber, minerals, proteins, lipids, and vitamins. The vitamins present in rice bran include those of the B complex (B(1) and B(3)), which affect the central nervous system (natural antidepressant and tranquilizer effects) acting in schizophrenia, neuralgia, and fatigue. The elevated plus maze (EPM) test is a model widely used for the study of anxiety in animals. The forced swimming (FS) test is the model used most often for evaluating the antidepressant activity in animal models in pharmacology. This study examined the behavior of 32 male Wistar rats, 21 days old, in the FS and EPM tests after treatment with strawberry- or chocolate-flavored rice bran drink for 28 days. The concentration of adrenocorticotropic hormone in the plasma of the animals was determined at the beginning and end of treatment. The values found (<1.0 mg/dL) showed no significant difference between the test and control groups in the periods analyzed. In the EPM, ingesting the chocolate-flavored drink showed an anxiogenic trend in the rats, and the strawberry-flavored rice bran drink led to an anxiolytic profile, although the difference was not statistically significant (P > .05). In the FS test, the duration of immobility of rats in groups consuming rice bran drinks was higher than in the control group, but without a statistically significant difference (P > .05). However, this result may indicate a tendency toward an effect on the central nervous system of the animals after the ingestion of the rice bran beverage.

Consumption of yerba mate ( Ilex paraguariensis ) improves serum lipid parameters in healthy dyslipidemic subjects and provides an additional LDL-cholesterol reduction in individuals on statin therapy.

The objective of this study was to verify the effect of yerba mate (Ilex paraguariensis) consumption on lipid and lipoprotein levels in humans. One hundred and two individuals participated of this single-blind controlled trial. Normolipidemic (n = 15), dyslipidemic (n = 57), and hypercholesterolemic subjects on long-term statin therapy (n = 30) ingested 330 mL, 3 times/day, of green or roasted yerba mate infusions for 40 days. In normolipidemic subjects, yerba mate consumption reduced LDL-cholesterol by 8.7% (p < 0.05). Compared with the baseline period, yerba mate intake by dyslipidemic individuals for 20 and 40 days lowered LDL-cholesterol by 8.1 and 8.6% (p < 0.001) and non-HDL cholesterol by 5.4 and 6.5% (p < 0.01). After 20 days of yerba mate intake, apolipoprotein B was reduced by 6.0% (p < 0.05) and HDL-cholesterol was increased by 4.4% (p < 0.01). In all participants triglyceride levels remained unchanged. The consumption of yerba mate by hypercholesterolemic individuals on statin therapy promoted additional 10.0 and 13.1% reductions in LDL-C after 20 and 40 days, respectively (p < 0.001) and increased HDL-cholesterol by 6.2% after 40 days (p < 0.05). It was thus concluded that intake of yerba mate infusion improved the lipid parameters in normolipidemic and dyslipidemic subjects and provided an additional LDL-cholesterol reduction in hypercholesterolemic subjects on statin treatment, which may reduce the risk for cardiovascular diseases.

Interferência dos ácidos graxos ômega-3 nos lipídeos sangüíneos de ratos submetidos ao exercício de natação / Omega-3 fatty acids interference on the blood lipids of rats subjected to swimming exercise

OBJETIVO: Investigar os efeitos da suplementação com ácidos graxos ômega-3, nas doses de 0,5 e 1,0g/kg/dia, nos lipídeos sangüíneos de ratos submetidos ou não ao protocolo do nado. MÉTODOS: Ratos Wistar foram divididos em grupos: controle, controle+nado, ácidos graxos ômega-3 e ácidos graxos ômega-3+nado. Os ácidos graxos ômega-3 e ácidos graxos ômega-3+nado receberam suplementação; os demais receberam água por gavagem. Os controle+nado e ácidos graxos ômega-3+nado foram submetidos ao exercício. Foram avaliadas as concentrações plasmáticas de colesterol total, triglicérides e lipoproteína de alta densidade, antes e após os procedimentos experimentais. RESULTADOS: No protocolo de 0,5g/kg/dia, em relação às concentrações de colesterol total, foi observada redução significativa proporcionalmente maior no grupo ácidos graxos ômega-3+nado, apesar de o grupo controle+nado e o ácidos graxos ômega-3 também terem apresentado diminuição. No ensaio de 1,0g/kg/dia todos os grupos apresentaram uma diminuição que foi maior, respectivamente, no ácidos graxos ômega-3+nado e, a seguir, no ácidos graxos ômega-3. Quanto aos triglicérides, foram encontradas reduções em todos os grupos experimentais, que foi maior no grupo ácidos graxos ômega-3+nado, do protocolo de 0,5g/kg/dia, enquanto que no de 1,0g/kg/dia a diminuição foi significativa apenas nos grupos ácidos graxos ômega-3 e ácidos graxos ômega-3+nado. Quanto ao HDL, no protocolo de 0,5g/kg/dia foi encontrado aumento nos animais que não foram suplementados, enquanto que em todos os grupos de 1,0g/kg/dia houve uma diminuição do HDL. CONCLUSÃO: A suplementação com ácidos graxos ômega-3 nas doses 0,5 ou 1,0g/kg/dia, associada ao nado, reduzem as concentrações plasmáticas de colesterol total e triglcérides, mas estudos adicionais, também com outras doses, são necessários para a compreensão da relação entre a ingestão de óleo de peixe e as concentrações de lipídeos sangüíneos.

OBJECTIVE: To investigate the effects of omega-3 fatty acid supplementation at doses of 0.5 and 1.0g/kg/day on the blood lipids of rats submitted or not to swimming exercise. METHODS: Wistar rats were divided into the following groups: control, control+swimming, omega-3 fatty acids and omega-3 fatty acids+swimming. The omega-3 fatty acids and omega-3 fatty acids+swimming groups received supplements by gavage, while the remaining animals received water by the same method. The control+swimming and omega-3 fatty acids +swimming groups were submitted to exercise. Plasma concentrations of total cholesterol, triglycerides and HDL were determined before and after the experimental procedures. RESULTS: The concentrations of total cholesterol in the 0.5g/kg/day groups reduced proportionally more in the omega-3 fatty acids+swimming group, even though total cholesterol of the control+swimming and omega-3 fatty acids groups also decreased. Total cholesterol decreased in both groups receiving 1.0g/kg/day supplementation, but the decrease was higher in the omega-3 fatty acids+swimming group than in the omega-3 fatty acids group. Triglycerides also decreased in all experimental groups. The greatest decrease was seen in the omega-3 fatty acids+swimming group receiving 0.5g/kg/day supplementation. In the 1.0g/kg/day protocol, the decrease was significant in both groups: the omega-3 fatty acids and omega-3 fatty acids+swimming groups. HDL increased among the non-supplemented animals and decreased among the animals receiving a supplementation of 1.0g/kg/day. CONCLUSION: Omega-3 fatty acid supplementation at doses of 0.5 or 1.0g/kg/day associated with swimming exercise reduced plasma concentrations of total cholesterol and triglycerides, yet additional studies, including varying doses, are necessary to better understand the relationship between ingestion of fish oil and blood lipid concentrations.

Consumption of green tea favorably affects oxidative stress markers in weight-trained men.

OBJECTIVE: This study investigated the effects of the consumption of green tea (GT) for 7 d on biomarkers of oxidative stress in young men undergoing resistance exercise. METHODS: Fourteen subjects performed a bench press exercise (four sets, 10 to 4 repetitions) after undergoing a period without (control group) or with the intake of GT (GT group; 2 g of leaves in 200 mL of water, three times per day). Blood samples were obtained before and after exercise and analyzed for total antioxidant capacity (ferric reducing ability of plasma [FRAP]), total polyphenols, reduced glutathione (GSH), lipid hydroperoxide (LH) and thiobarbituric acid-reactive substances, creatine kinase (CK), aspartate aminotransferase (AST), xanthine oxidase (XO), hypoxanthine, and uric acid (UA). RESULTS: In the control group, exercise did not affect the values of LH, thiobarbituric acid-reactive substances, and FRAP, although it did reduce the levels of GSH (P < 0.05). In addition, exercise increased CK, AST, and XO activities, although it did not change the values for hypoxanthine or UA. Green tea reduced the postexercise concentration of LH and increased the values of total polyphenols, GSH, and FRAP. GT also inhibited a significant rise in CK and XO activities induced by exercise. Furthermore, GT decreased the AST activity and hypoxanthine and UA concentrations before and after exercise. The assessment of food consumption revealed that the participants had an unbalanced diet, particularly in relation to vitamin E and carotenoids. CONCLUSION: Consumption of GT, a beverage rich in polyphenols, may offer protection against the oxidative damage caused by exercise, and dietary guidance for sports participants should be emphasized.