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Lucja Pilaczynska-Szczesniak, A. Skarpanska-Steinborn, E. Deskur, P. Basta, and M. Horoszkiewicz-Hassan

The aim of the study was to investigate the influence of an increased intake of anthocyanins, contained in chokeberry juice, on the redox parameters in rowers performing a physical exercise during a 1-month training camp. The athletes were randomly assigned to receive 150 mL of chokeberry juice daily, containing 23 mg/100 mL of anthocyanins (supplemented group), or placebo (control group). Before and after the supplementation period, the subjects performed an incremental rowing exercise test. Blood samples were taken from the antecubital vein before each exercise test, 1 min after the test, and following a 24-h recovery period. After the supplementation period, TBARS concentrations in the samples collected 1 min after the exercise test and following a 24-h recovery period were significantly lower in the subjects receiving chokeberry juice than in the control group. In the supplemented group, glutathione peroxidase activity was lower in the samples collected 1 min after the exercise test, and superoxide dismutase activity was lower in the samples taken following a 24-h recovery, as compared to the subjects receiving placebo. These findings indicate that an increased intake of anthocyanins limits the exercise-induced oxidative damage to red blood cells, most probably by enhancing the endogenous antioxidant defense system.

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Aiping Chi, Liang Tang, Jing Zhang, and Kunru Zhang

Purpose:

To investigate the effects of polysaccharide from Gynostemma pentaphyllum on antioxidant activity in skeletal muscle of mice exercised to exhaustion.

Methods:

Three polysaccharide fractions were obtained from G. pentaphyllum polysaccharide (GPP) and termed GPP1-a, GPP2-b, and GPP3-a. Gas chromatography (GC) and infrared spectrum of the polysaccharides were determined. The fractions were orally administrated to mice once daily for 1 wk. The exercise time to exhaustion was assessed using a forced swim test of mice after a week. The glucose, creatine phosphokinase, and lactic dehydrogenase in serum; the activity of superoxide dismutase and glutathione peroxidase; and the levels of malondialdehyde (MDA) and glycogen in muscle were determined.

Results:

The results of GC demonstrated that GPP1-a, GPP2-b, and GPP3-a were composed of different monosaccharides with distinct molar ratios. Infrared spectrum showed that the main typicals of GPP1-a and GPP2-b were β-configuration and the main typical of GPP3-a was α-configuration. Among the 3 fractions of GPP, GPP1-a administration significantly prolonged exercise time to exhaustion of mice, increased glycogen level and some of antioxidant enzyme activities, and decreased MDA level in muscle.

Conclusions:

The mechanism by which GPP1-a prolonged exercise time to exhaustion in mice may be associated with scavenging reactive oxygen species excessively produced and further increasing glycogen levels in skeletal muscle.

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Piotr Basta, Łucja Pilaczyńska-Szczȩśniak, Donata Woitas-Ślubowska, and Anna Skarpańska-Stejnborn

This investigation examined the effect of supplementation with Biostimine, extract from aloe arborescens Mill. leaves, on the levels of pro-oxidant–antioxidant equilibrium markers and anti- and proinflammatory cytokines in rowers subjected to exhaustive exercise. This double-blind study included 18 members of the Polish Rowing Team. Subjects were randomly assigned to the supplemented group (n = 9), which received one ampoule of Biostimine once daily for 4 weeks, or to the placebo group (n = 9). Subjects performed a 2,000-meter-maximum test on a rowing ergometer at the beginning and end of the preparatory camp. Blood samples were obtained from the antecubital vein before each exercise test, 1 min after completing the test and after a 24-hr recovery period. Superoxide dismutase and glutathione peroxidase activity as well as the concentration of thiobarbituric acid reactive substances (TBARS) were assessed in erythrocytes. In addition, total antioxidant capacity (TAC) and creatine kinase activity were measured in plasma samples, and cytokine (IL-6, IL-10) concentrations were determined in the serum. Before and after Biostimine supplementation, exercise significantly increased the values of SOD, IL-6, IL-10, and TBARS in both groups. However, postexercise and recovery levels of TBARS were significantly lower in athletes receiving Biostimine than in controls. After supplementation, TAC was the only variable with the level being significantly higher in the supplemented group than in the placebo group. Consequently, we can conclude that Biostimine supplementation reduces the postexercise level of TBARS by increasing the antioxidant activity of plasma but has no effect on inflammatory markers.

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J.A. Goon, A.H. Noor Aini, M. Musalmah, M.Y. Yasmin Anum, W.M. Wan Nazaimoon, and W.Z. Wan Ngah

Background:

The biochemical mechanisms involving oxidative stress to explain the relationship between exercise and healthy aging are still unclear.

Methods:

Tai Chi participants and matched sedentary volunteers age 45 and above were enrolled. Glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) activities; levels of DNA damage using the comet assay; and malondialdehyde (MDA) and advanced glycation end products (AGE) were determined at 0, 6, and 12 months.

Results:

Tai Chi subjects had decreased normal and increased mildly damaged DNA with elevated GPx activity after 6 months (n = 25). Plasma MDA and AGE concentrations decreased significantly after 12 months (n = 15) accompanied by increased SOD activity. This may be attributed to the hormesis effect, whereby mild induction of oxidative stress at the first 6 months of exercise resulted in stimulation of antioxidant defenses. These parameters were unchanged in the sedentary subjects in the first 6 months (n = 27) except for elevated SOD activity. After 12 months, the sedentary subjects (n = 17) had decreased normal DNA and increased severely damaged DNA with unaltered MDA and AGE levels while SOD and GPx activities were significantly elevated.

Conclusion:

Regular Tai Chi exercise stimulated endogenous antioxidant enzymes and reduced oxidative damage markers.

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Zekine Lappalainen, Jani Lappalainen, David E. Laaksonen, Niku K.J Oksala, Savita Khanna, Chandan K. Sen, and Mustafa Atalay

Thioredoxin (TRX) is a protein disulfide reductase that plays an important role in many thiol-dependent cellular reductive processes, antioxidant protection, and signal transduction. Moreover, TRX reduces and maintains the function of many proteins during oxidative stress, which is increased in diabetes. The authors recently reported that diabetes impairs brain redox status and TRX response to exercise training. As a continuation of their studies, they hypothesized that alpha-lipoic acid, a natural thiol antioxidant, has a favorable effect on the brain TRX and glutathione (GSH) system in diabetes. Streptozotocin-induced diabetes was used as a chronic model and exhaustive exercise as an acute model for disrupted redox balance. Half the diabetic and nondiabetic animals were subjected to a bout of exhaustive exercise after 8 wk with or without lipoic acid and analyzed for key thiol antioxidants. Lipoic acid neither altered diabetes-induced oxidative stress as assessed by the increased ratio of oxidized to total GSH nor had any impact on the antioxidant protein response to exercise. However, lipoic acid increased mRNA of TRX-interacting protein, an inhibitor of TRX-1, and glutaredoxin-1 in diabetes. Exercise increased TRX-1 mRNA in both diabetic and nondiabetic animals but had no effect on TRX-1 protein. Cytosolic superoxide dismutase mRNA was only increased in diabetes, whereas exercise increased the protein levels in nondiabetic animals. The findings suggest that exhaustive exercise induces mRNA of TRX-1 in the brain and that lipoic acid cannot prevent diabetes-induced disturbances in GSH homeostasis. Because lipoic acid increased TRX-interacting protein transcription in diabetes, high doses may impair TRX-1 homeostasis.

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Manfred Lamprecht, Peter Hofmann, Joachim F. Greilberger, and Guenther Schwaberger

Purpose:

To assess the effects of an encapsulated antioxidant concentrate (EAC) and exercise on lipid peroxidation (LIPOX) and the plasma antioxidant enzyme glutathione peroxidase (Pl-GPx).

Methods:

Eight trained male cyclists (VO2max > 55 ml · kg−1 · min−1) participated in this randomized, placebo-controlled, double-blinded, crossover study and undertook 4 cycle-ergometer bouts: 2 moderate exercise bouts over 90 min at 45% of individual VO2max and 2 strenuous exercise bouts at 75% of individual VO2max for 30 min. The first 2 exercise tests—1 moderate and 1 strenuous—were conducted after 4 weeks wash-out and after 12 and 14 days of EAC (107 IU vitamin E, 450 mg vitamin C, 36 mg β-carotene, 100 μg selenium) or placebo treatment. After another 4 weeks wash-out, participants were given the opposite capsule treatment and repeated the 2 exercise tests. Physical exercise training was equal across the whole study period, and nutrition was standardized by a menu plan the week before the tests. Blood was collected before exercise, immediately postexercise, and 30 min and 60 min after each test. Plasma samples were analyzed for LIPOX marker malondialdehyde (MDA) and the antioxidant enzyme pl-GPx.

Results:

MDA concentrations were significantly increased after EAC supplementation at rest before exercise and after moderate exercise (p < .05). MDA concentrations showed no differences between treatments after strenuous exercise (p > .1). Pl-GPx concentrations decreased at all time points of measurement after EAC treatment (p < .05).

Conclusions:

The EAC induced an increase of LIPOX as indicated by MDA and decreased pl-GPx concentrations pre- and postexercise.

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Edith Filaire, Alain Massart, Hugues Portier, Matthieu Rouveix, Fatima Rosado, Anne S. Bage, Mylène Gobert, and Denys Durand

The aim of this investigation was to assess the effects of 6 wk of eicosapentanoic acid (EPA) and docosahexanoic acid (DHA) supplementation on resting and exercise-induced lipid peroxidation and antioxidant status in judoists. Subjects were randomly assigned to receive a placebo or a capsule of polyunsaturated fatty acids (PUFAs; 600 mg EPA and 400 mg DHA). Blood samples were collected in preexercise and postexercise conditions (judo-training session), both before and after the supplementation period. The following parameters were analyzed: α-tocopherol, retinol, lag phase, maximum rate of oxidation (Rmax) during the propagating chain reaction, maximum amount of conjugated dienes (CDmax) accumulated after the propagation phase, nitric oxide (NO) and malondyaldehide (MDA) concentrations, salivary glutathione peroxidase activity, and the lipid profile. Dietary data were collected using a 7-day dietary record. A significant interaction effect between supplementation and time (p < .01) on triglycerides was noted, with values significantly lower in the n-3 long-chain-PUFA (LCPUFA) group after supplementation than in the placebo group. Significant interaction effects between supplementation and time on resting MDA concentrations and Rmax were found (p = .03 and p = .04, respectively), with elevated values in the n-3 LCPUFA group after supplementation and no change in the placebo group’s levels. The authors observed a significantly greater NO and oxidative-stress increase with exercise (MDA, Rmax, CDmax, and NO) in the n-3 LCPUFA group than with placebo. No main or interaction effects were found for retinol and α-tocopherol. These results indicate that supplementation with n-3 LCPUFAs significantly increased oxidative stress at rest and after a judo-training session.

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Miguel David Ferrer, Pedro Tauler, Antoni Sureda, Pedro Pujol, Franchec Drobnic, Josep Antoni Tur, and Antoni Pons

Soccer-associated oxidative stress has barely been studied. The aims of this study were to establish the effect of a soccer training match and the effect of a diet supplementation with a multivitamin complex and coenzyme Q during 3 months of soccer training on the pro-oxidant and antioxidant status of lymphocytes. In a randomized, double-blind trial, 19 male preprofessional soccer players were treated with either an antioxidant nutrient cocktail or placebo for 90 days. After this period the athletes played a soccer match lasting 60 min. All determinations were made under basal conditions before and after the training period and after the match. Basal lymphocyte hydrogen peroxide (H2O2) production did not change after the 3 months of training. Catalase activity decreased (about 50%) after the 3 months, whereas glutathione reductase increased its activity (150–200%) both with placebo and in the supplemented group. Basal ascorbate levels were maintained during the training period, whereas α-tocopherol and MDA decreased (about 40%) in both groups. The match increased H2O2 production (180%) in both groups when the lymphocytes were stimulated with phorbol myristate acetate, and it also increased MDA levels (150%). Antioxidant enzyme activities and antioxidant vitamin levels were maintained before and after the match. Regular soccer training modifies the lymphocyte strategy to eliminate ROS and increases protection against oxidative damage. A friendly soccer match raises lymphocyte capacity to produce ROS and oxidative damage, but it is not enough to induce a defensive response, thus leading to a situation of postexercise oxidative stress. Supplementation with low doses of antioxidant vitamins and coenzyme Q does not modify the endogenous antioxidant response to training.

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Eyad Alshammari, Shahida Shafi, Jaana Nurmi-Lawton, Andrew Taylor, Susan Lanham-New, and Gordon Ferns

Physical activity is associated with the generation of reactive oxygen species and may lead to decreased levels of plasma antioxidants and increased oxidant stress. Some studies have reported that antioxidant supplements can reduce the consequences of oxidative stress during exercise. In this study the authors aimed to assess the chronic effects of exercise on endogenous serum antioxidant enzyme concentrations. Glutathione peroxidase (GPx) and superoxide dismutase (SOD) activity were measured in adolescent girls who were either competitive gymnasts or sedentary controls. The relationship between age, body-mass index, dietary intake, trace-element status, and serum GPx and SOD was determined. The participants in the study were part of a 3-yr longitudinal investigation of exercise and peak bone-mass development in 38 competitive gymnasts and 40 healthy sedentary adolescent females 8–17 yr of age. Serum GPx and SOD were measured using colorimetric assays, and trace elements were measured using inductively coupled plasma mass spectrometry. The mean serum GPx concentrations were significantly higher in the gymnasts than in the sedentary females (157 ± 11.1 vs. 126 ± 8.8 U/ml, p < .05). In contrast, serum SOD concentrations were significantly lower in the gymnasts than in the sedentary group (7.24 ± 2.6 vs. 8.57 ± 2.3 U/ml, p < .05). Serum selenium, zinc, and copper were higher in the physically active group than in the inactive group (0.89 ± 0.03, 10.86 ± 0.39, 14.50 ± 0.50 vs. 0.81 ± 0.03, 10.32 ± 0.28, and 14.38 ± 0.42 μmol/L, respectively), although only serum selenium reached statistical significance (p < .05). The findings show that young female gymnasts have an altered antioxidant enzyme profile compared with their less physically active peers.

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Andrea J. Braakhuis, Will G. Hopkins, and Timothy E. Lowe

The beneficial effects of exercise and a healthy diet are well documented in the general population but poorly understood in elite athletes. Previous research in subelite athletes suggests that regular training and an antioxidant-rich diet enhance antioxidant defenses but not performance.

Purpose:

To investigate whether habitual diet and/or exercise (training status or performance) affect antioxidant status in elite athletes.

Methods:

Antioxidant blood biomarkers were assessed before and after a 30-min ergometer time trial in 28 male and 34 female rowers. The antioxidant blood biomarkers included ascorbic acid, uric acid, total antioxidant capacity (TAC), erythrocyte- superoxide dismutase, glutathione peroxidase (GPx), and catalase. Rowers completed a 7-d food diary and an antioxidant-intake questionnaire. Effects of diet, training, and performance on resting biomarkers were assessed with Pearson correlations, and their effect on exercise-induced changes in blood biomarkers was assessed by a method of standardization.

Results:

With the exception of GPx, there were small to moderate increases with exercise for all markers. Blood resting TAC had a small correlation with total antioxidant intake (correlation .29; 90% confidence limits, ±.27), and the exercise-induced change in TAC had a trivial to small association with dietary antioxidant intake from vitamin C (standardized effect .19; ±.22), vegetables (.20; ±.23), and vitamin A (.25; ±.27). Most other dietary intakes had trivial associations with antioxidant biomarkers. Years of training had a small inverse correlation with TAC (−.32; ±.19) and a small association with the exercise-induced change in TAC (.27; ±.24).

Conclusion:

Training status correlates more strongly with antioxidant status than diet does.