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Cashew apple juice supplementation enhances leukocyte count by reducing oxidative stress after high-intensity exercise in trained and untrained men.
Prasertsri, P, Roengrit, T, Kanpetta, Y, Tong-Un, T, Muchimapura, S, Wattanathorn, J, Leelayuwat, N
Journal of the International Society of Sports Nutrition. 2019;16(1):31
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High-intensity aerobic training has been shown to suppress leukocyte counts in moderately fit athletes. The aim of this study to explore possible advantageous effects of cashew apple juice (CAJ) supplementation, and, if present, to identify the possible mechanisms underlying those effects. The study is a double-blind randomised cross-over design with two treatment arms: CAJ supplementation and placebo. Ten moderately (endurance) trained and untrained men were randomized to one of the two groups for four weeks, with a four-week wash out period. Results showed that CAJ supplementation for four weeks increased leukocyte (a type of blood cell) counts, while simultaneously decreasing oxidative stress, following an acute bout of high-intensity exercise in trained men. Furthermore, the CAJ supplementation increased neutrophil (a type of white blood cell) counts while simultaneously reducing oxidative stress and stress hormone concentrations in untrained men. The antioxidant effects following exercise were observed in both endurance-trained and untrained men. Authors conclude that CAJ supplementation is beneficial to men, both in resting states and in response to an acute bout of high-intensity aerobic exercise.
Abstract
BACKGROUND Cashew apple juice (CAJ) was shown to improve immunological mechanisms by regulating a balance between reactive oxygen species and antioxidant concentrations. However, no study exploring the effects of the CAJ and training status on the immune system and oxidative stress induced by exercise. Therefore, we investigated the effects of CAJ supplementation primarily on leukocyte counts and secondary on oxidative stress and cortisol changes after high-intensity exercise in trained and untrained men. METHODS Ten moderately (endurance) trained (Age = 21.5 ± 0.97 yr., VO2max = 45.6 ± 4.12 mL/kgBM/min) and ten sedentary men (Age = 20.4 ± 2.72 yr., VO2peak = 32.2 ± 7.26 mL/kgBM/min) were randomized to ingest either daily CAJ or a placebo at 3.5 mL/kgBM/day for 4 weeks, with a four-week washout period. Before and after each period, they performed 20-min, high-intensity cycling (85% VO2max), with blood samples collected immediately preceding and the following exercise. Samples were analyzed to determine leukocyte counts, malondialdehyde, 8-isoprostane, and cortisol concentrations. A repeated measures analysis of variance was used to examine the effects of supplement and training status over time with an alpha level of 0.05. RESULTS There was no interaction between supplement and training status on those variables before and after exercise. However, CAJ raised resting neutrophil counts and exercise-induced leukocyte counts in the trained group (all p < 0.05). Besides, CAJ significantly reduced plasma malondialdehyde concentrations at rest and after exercise and reduced the post-exercise plasma 8-isoprostane concentration in both groups of subjects (p < 0.05). Moreover, CAJ reduced plasma cortisol after exercise in the untrained subjects. CONCLUSIONS We suggest that 4-week CAJ supplementation can enhance exercise-induced leukocyte and resting neutrophil counts in trained men. The possible mechanism is a reduction in oxidative stress. However, the supplementation did not change the immune responses of untrained men, but it did reduce stress hormone concentrations. TRIAL REGISTRATION NUMBER TCTR20181127002 Registered 26 November 2018 "retrospectively registered".
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The effect of a short-term low-carbohydrate, high-fat diet with or without postmeal walks on glycemic control and inflammation in type 2 diabetes: a randomized trial.
Myette-Côté, É, Durrer, C, Neudorf, H, Bammert, TD, Botezelli, JD, Johnson, JD, DeSouza, CA, Little, JP
American journal of physiology. Regulatory, integrative and comparative physiology. 2018;315(6):R1210-R1219
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Inflammation is associated with the pathogenesis of insulin resistance, type 2 diabetes (T2D), and related complications. Lifestyle therapy is a frontline treatment for improving glucose control in people with T2D. The main aim of this study was to determine whether reducing hyperglycaemia with a low-carbohydrate high-fat (LC) diet could lower markers of innate immune cell activation and systemic inflammation in people with T2D. A secondary aim was to examine if the combination of an LCHF diet with strategically timed postmeal walking was superior to an LCHF diet alone. The study is a randomised cross over study which enrolled Individuals with physician-diagnosed T2D to complete three short-term controlled-intervention periods. Sixteen participants were enrolled (men = 8 and women = 8) who were aged between 48 and 72 years. Results indicate that while LC and LC together with exercise (LC+Ex) led to superior improvements in glucose control and fasting proinsulin (the pro-hormone precursor to insulin) levels as compared with low-fat low glycaemic index diet (GL), all three diets (GL, LC and LC+Ex), appeared to lower a particular marker of cellular inflammation over the short-term. Authors conclude that an LCHF diet with or without daily postmeal walks improved four-day glycaemic control and fasting proinsulin levels compared with a GL diet.
Abstract
Lowering carbohydrate consumption effectively lowers glucose, but impacts on inflammation are unclear. The objectives of this study were to: 1) determine whether reducing hyperglycemia by following a low-carbohydrate, high-fat (LC) diet could lower markers of innate immune cell activation in type 2 diabetes (T2D) and 2) examine if the combination of an LC diet with strategically timed postmeal walking was superior to an LC diet alone. Participants with T2D ( n = 11) completed a randomized crossover study involving three 4-day diet interventions: 1) low-fat low-glycemic index (GL), 2) and 3) LC with 15-min postmeal walks (LC+Ex). Four-day mean glucose was significantly lower in the LC+Ex group as compared with LC (-5%, P < 0.05), whereas both LC+Ex (-16%, P < 0.001) and LC (-12%, P < 0.001) conditions were lower than GL. A significant main effect of time was observed for peripheral blood mononuclear cells phosphorylated c-Jun N-terminal kinase ( P < 0.001), with decreases in all three conditions (GL: -32%, LC: -45%, and LC+Ex: -44%). A significant condition by time interaction was observed for monocyte microparticles ( P = 0.040) with a significant decrease in GL (-76%, P = 0.035) and a tendency for a reduction in LC (-70%, P = 0.064), whereas there was no significant change in LC+Ex (0.5%, P = 0.990). Both LC (-27%, P = 0.001) and LC+Ex (-35%, P = 0.005) also led to significant reductions in circulating proinsulin. An LC diet improved 4-day glycemic control and fasting proinsulin levels when compared with GL, with added glucose-lowering benefits when LC was combined with postmeal walking.