Combined antioxidant treatment effects on blood oxidative stress after eccentric exercise

PURPOSE: This study was designed to ascertain the effects of a combination antioxidant therapy on plasma protein carbonyls (PC), malondialdehyde (MDA), and whole blood total (TGSH), oxidized (GSSG), and reduced (GSH) glutathione in non-resistance trained females after eccentric resistance exercise. METHODS: Eighteen women (aged 19-31 yr) were randomized in a double-blind manner to either an antioxidant supplement (N = 9; 400 IU vitamin E, 1 g vitamin C, and 90 mug selenium per day) or a lactose placebo (N = 9) for 14 d before and for 2 d after eccentric elbow flexor exercise. Blood samples taken before and immediately, 2, 6, 24, and 48 h postexercise were analyzed for PC, MDA, TGSH, and GSSG. RESULTS: No treatment by time interaction was noted for any variable, with all blood markers experiencing a change after the exercise in both conditions. Time main effects were observed for PC, MDA, and GSSG, with values elevated above preexercise after the eccentric exercise, whereas GSH concentration decreased after the eccentric exercise. Antioxidant supplementation resulted in a condition main effect for PC and MDA, with lower values compared with placebo. The antioxidant treatment attenuated the rise in both PC (75%) and MDA (100%). CONCLUSION: These data suggest that eccentric resistance exercise can increase blood biomarkers of oxidative stress in non-resistance trained females, and this vitamin E, C, and selenium supplementation can attenuate the rise in PC and MDA.     

Effect of vitamin supplementation on lung injury and running performance in a hot, humid, and ozone-polluted environment

In this study, the effect of vitamin C and E supplementation on lung injury and performance of runners were analyzed. Using a randomized, double‐blinded, crossover design, nine runners participated in two experimental trials: a 2‐week Vitamin trial (vitamin C = 500 mg/day + vitamin E = 100 IU/day) and a 2‐week Placebo trial. At the end of each supplementation period the runners performed an 8‐km time‐trial run in a hot (31°C), humid (70% rh), and ozone‐polluted (0.10 ppm O₃) environmental chamber. Nasal lavage and blood samples were collected pre‐, post‐, and 6‐h post‐exercise to assess antioxidant status and CC16 as lung injury marker. Higher plasma (pre‐ and post‐exercise) and nasal lavage (post‐exercise) antioxidant concentration were found for the Vitamin trial. Nevertheless, this did not result in performance differences (Vitamin trial: 31:05 min; Placebo trial: 31:54 min; P = 0.075) even though significant positive correlations were found between antioxidant concentration and improvement in time to complete the run. CC16 was higher post‐exercise in the Placebo trial (P < 0.01) in both plasma and nasal lavage. These findings suggest that antioxidant supplementation might help to decrease the lung injury response of runners when exercising in adverse conditions, but has little effect on performance.     

Contraction-induced muscle damage is unaffected by vitamin E supplementation

PURPOSE: Vitamin E supplementation may confer a protective effect against eccentrically biased exercise-induced muscle damage through stabilization of the cell membrane and possibly via inhibition of free radical formation. Evidence supporting a protective role of vitamin E after contraction-induced muscle injury in humans is, however, inconsistent. The present study sought to determine the effect of vitamin E supplementation on indices of exercise-induced muscle damage and the postexercise inflammatory response after performance of repeated eccentric muscle contractions. METHODS: Young healthy men performed a bout of 240 maximal isokinetic eccentric muscle contractions (0.52 rad.s-1) after being supplemented for 30 d with either vitamin E (N = 9; 1200 IU.d-1) or placebo (N = 7; safflower oil). RESULTS: Measurements of torque (isometric and concentric) decreased (P < 0.05) below preexercise values immediately post- and at 48 h post-exercise. Biopsies taken 24 h postexercise showed a significant increase in the amount of extensive Z-band disruption (P < 0.01); however, neither the torque deficit nor the extent of Z-band disruption were affected by vitamin E. Exercise resulted in increased macrophage cell infiltration (P = 0.05) into muscle, which was also unaffected by vitamin E. Serum CK also increased as a result of the exercise (P < 0.05) with no effect of vitamin E. CONCLUSION: We conclude that vitamin E supplementation (30 d at 1200 IU.d-1), which resulted in a 2.8-fold higher serum vitamin E concentration (P < 0.01), had no affect on indices of contraction-induced muscle damage nor inflammation (macrophage infiltration) as a result of eccentrically biased muscle contractions.     

Prooxidant-antioxidant equilibrium in rowers: effect of a single dose of vitamin E

AIM: The purpose of this research was to explain whether a single dose of vitamin E influences on disturbances of pro-oxidant-antioxidant equilibrium induced a laboratory 2,000 m rowing test. METHODS: The athletes were divided into two groups: vitamin E (1.000 mg alfa-tocopherol acetate) and P (placebo: cod-liver oil) supplemented 3 h before exercise. In the subjects' blood levels of following parameters were estimated: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), lipid peroxidation products (TBARS) and protein carbonyls (PC). Creatine kinase (CK) and beta-glucuronidase (betaG) activities were also measured as markers of muscle damage. RESULTS: The applied exercise at maximal intensity (lactate: vitamin E=14.39+/-1.77 mmol/L, P=14.09+/-1.4 mmol/L) caused significant changes in the tested parameters in both groups: SOD (vitamin E ?30%, P ?50%), CAT (vitamin 70%, P 12%), GPx (vitamin 49%, P 45%), TBARS (vitamin 70%, P 71%), PC (vitamin 41%, P 78%), CK (vitamin 19%, P 32%), betaG (vitamin 42%, P 47%). The P/A ratio (TBARS/SOD+CAT+GPx) was significantly lower in vitamin E in comparison with placebo, but after 30 min and 24 h restitution it returned to pre-exercise level. Between P/A ratio and PC concentration there was observed positive correlation (P<0.001). No effect of vitamin E on CK and betaG activities were observed. CONCLUSIONS: A single dose of 1,000 mg vitamin E enhances oxidative defense thus attenuates oxidative damage but it is not so much relevant to recommend the antioxidant supplementation by rowers.     

Muscle soreness and damage parameters after prolonged intermittent shuttle-running following acute vitamin C supplementation

Exercise-induced free-radical production may be partly responsible for muscle soreness and damage following demanding exercise. A number of studies have investigated the effect of antioxidant supplementation although there is a paucity of information regarding vitamin C. Therefore the aim of the present study was to investigate the effect of vitamin C supplementation on exercise-induced muscle soreness and damage. Nine habitually active males consumed a 1 g dose of vitamin C 2 h before exercise, and on another occasion consumed an identical placebo. The exercise comprised a 90 min intermittent shuttle-running test, which was designed to simulate the multiple-sprint sports. Vitamin C supplementation increased plasma concentrations of vitamin C before exercise, and plasma concentrations continued to increase during the shuttle-run to reach a peak of approximately 200 micromol x l(-1) immediately after exercise. However, muscle soreness, and markers of both muscle damage (creatine kinase and aspartate aminotransferase) and lipid peroxidation (malondialdehyde) were elevated to an equal extent after exercise in placebo and supplemented trials. Therefore acute supplementation with vitamin C had no beneficial effects although it is possible that such short-term vitamin C supplementation was ineffective because it occurred at an inappropriate time.     

Effect of vitamin E supplementation on hypoxia-induced oxidative damage in male albino rats

BACKGROUND: There is growing evidence that free radicals mediated oxidative injury due to inadequate oxygen availability is an important factor in various pathologies at high altitude. Since vitamin E is known to protect the cells from oxidative damage due to its potent antioxidant properties, the present study was carried out to explore the effect of vitamin E supplementation on various hematological and biochemical parameters in hypoxia-induced oxidative stress in albino rats. METHODS: The experiments were conducted on male albino rats by intermittently exposing them to a simulated altitude of 7,576 m (25,000 ft), daily for 6 h for 15 d at 32 +/- 2 degrees C. The control group was fed vehicle only (1% Tween 80) and the experimental group was given vitamin E (40 mg per rat x d(-1)) orally, 5 d prior to and during the period of hypoxic exposure. The variables studied include: hemoglobin, hematocrit, RBC deformability index, alpha-tocopherol level, malondialdehyde (MDA), reduced glutathione (GSH), oxidized glutathione (GSSG), lactate dehydrogenase (LDH) and protein level in blood/plasma and various tissues. RESULTS: Significant increase in hematocrit and hemoglobin and decrease in RBC deformability index was observed on exposure to hypoxia while vitamin E supplementation maintained them at the normal level. Hypoxia led to the decrease in plasma vitamin E and blood glutathione (GSH) level and two-fold increase in the plasma malondialdehyde (MDA) level. Vitamin E supplementation, on the other hand, resulted in less of an increase in MDA and increased the GSH concentration significantly. LDH activity, which was elevated on exposure to hypoxia, was arrested on vitamin E supplementation. CONCLUSION: The results indicate that vitamin E supplementation results in preventing oxidative damage due to high altitude stress.     

Effects of endurance training on tissue glutathione homeostasis and lipid peroxidation in streptozotocin-induced diabetic rats

The aims of our study were to assess whether endurance training strengthens glutathione-dependent antioxidant defenses and decreases oxidative stress in experimental diabetes. Streptozotocin-induced diabetic rats were divided into trained and untrained groups, which were further divided into resting and acute exercise groups. Endurance training consisted of treadmill running for 8 weeks. For acute exhaustive exercise, graded treadmill running was conducted until exhaustion. Eight weeks' treadmill training increased the endurance, favorably decreased lipid peroxidation as measured by thiobarbituric acid reactive substances but not conjugated dienes levels in kidney and vastus lateralis muscle and upregulated glutathione peroxidase in red gastrocnemius muscle. However, it adversely decreased total glutathione level and glutathione peroxidase activity in kidney. Acute exhaustive exercise up-regulated glutathione peroxidase activity in liver. Endurance training did not prevent the increase in thiobarbituric acid reactive substances level in liver due to acute exhaustive exercise. Activities of glutathione disulfide reductase and glutathione S-transferase were not affected. Even though endurance training appeared to upregulate glutathione dependent antioxidant defense in skeletal muscle and to decrease lipid peroxidation in kidney and vastus lateralis muscle as measured by TBARS, our results suggests that beneficial effects of 8 weeks of endurance training are limited in this rat model of uncontrolled diabetes mellitus.     

维生素E对血液透析病人氧化应激的干预效果

目的　研究抗氧化剂维生素E对血液透析病人氧化应激状态的干预效果。方法　处于稳定状态的血液透析病人 5 6例 (不服用任何抗氧化药)采用自身对照的方法 ,观察 1个月后 ,随机均分为两个实验组 ,A组口服维生素E 2 0 0mg/d ,B组口服维生素E 4 0 0mg/d,服药 1个月 ;两组分别在观察期和服用维生素E干预期前后检测循环晚期氧化蛋白产物(AOPP)、丙二醛 (MDA)和谷胱甘肽过氧化物酶(GSHPx)水平以及血清维生素E浓度。另选 5 6例健康者作为正常对照组。结果　实验组血清AOPP、MDA水平明显高于同龄正常对照组(n =5 6 ,P <0 0 1) ,GSHPx、维生素E浓度明显低于正常人(P <0 0 1) ;透析病人在未服抗氧化药的 1个月观察期前后AOPP、MDA、GSHPx及维生素E浓度无明显变化 (P均 >0 0 5 ) ;A组治疗后 ,血清维生素E水平较治疗前明显增高 (P <0 0 1) ,但AOPP、MDA和GSHPx水平与治疗前相比无明显差异 ;B组治疗后血清维生素E、GSHPx水平较治疗前增高 (P <0 0 1,P <0 0 5 ) ,AOPP较治疗前明显降低 (P <0 0 1) ,但MDA水平无明显变化。结论　口服大剂量维生素E(4 0 0mg/d)可以改善血透病人的氧化应激状态 ;血透病人短期服用大剂量维生素E未见明显副作用。     

Neuroendocrine responses to running in women after zinc and vitamin E supplementation

PURPOSE: The study was undertaken to determine whether acute supplementation with zinc or vitamin E would modify neuroendocrine responses to physiologic stress. METHODS: Specifically, the effects of exhaustive running on blood glucose, lactate, ACTH, cortisol, growth hormone, prolactin, catecholamine, and interleukin 6 (IL-6) concentrations were determined in 10 eumenorrheic runners after supplementation with zinc (25 mg), vitamin E (400 IU), or placebo. Subjects ran at 65-70% of their VO2max, to exhaustion, on a treadmill during the follicular phase of their menstrual cycles over three cycles. RESULTS: There were no significant differences associated with supplementation for any of the hormonal and metabolic measures. Exercise, however, significantly (P<0.05) increased plasma lactate, ACTH, prolactin, and catecholamine concentrations, all of which peaked immediately after exercise (POST). Plasma cortisol concentrations were significantly (P<0.05) elevated at POST, and a further increase was noted 1 h after exercise. IL-6 concentrations rose linearly throughout exercise and reached peak values at POST. Exercise-induced changes were transient in that all measures returned to baseline within 24 h. CONCLUSIONS: Acute supplementation with zinc or vitamin E did not influence the effects of exhaustive running on metabolic and endocrine responses in women. The effects of chronic supplementation on neuroendocrine responses to exercise remain to be determined.     

磷脂对运动小鼠某些生化指标的改善作用

观察了补充磷脂对运动小鼠营养状况和自由基防御体系的影响。结果显示(1）补充磷脂能提高血清磷脂含量,增加血红蛋白，并且使血清白蛋白有上升趋势，改善机体营养状况，对力竭性运动后血红蛋白的恢复也有良好作用；(2）补充磷脂能提高机体部分组织抗自由基氧化的能力。(3）各组织中SOD活性、GPX活性、MDA含量是不相同的，其中SOD活性以股四头肌中最高，GPX活性以肝脏最高，而MDA含量以肾脏最低，这可能反映了各组织器官抗过氧化综合能力的差异；(4）补充磷脂不影响运动小鼠体重。     

The effects of fish oil and isoflavones on delayed onset muscle soreness

INTRODUCTION/PURPOSE: Fish oils (FO) have been shown to modulate the inflammatory response through alteration of the eicosanoid pathway. Isoflavones (ISO) appear to reduce the inflammatory pathway through their role as a tyrosine kinase inhibitor. Delayed onset muscle soreness (DOMS) develops after intense exercise and has been associated with an inflammatory response. Therefore, we hypothesized that physical parameters associated with DOMS could be decreased via the modulation of the inflammatory response by supplementing subjects with either FO or ISO. METHODS: 22 subjects were recruited and randomly assigned to one of three treatment groups: FO (1.8 g of omega-3 fatty acids x d(-1)), ISO (120 mg soy isolate x d(-1)), or placebo (PL) (Western fat blend and/or wheat flour). All treatment groups received 100-IU vitamin E x d(-1) to minimize lipid peroxidation of more highly unsaturated fatty acids. Subjects were supplemented 30 d before the exercise and during the week of testing and were instructed to refrain from unusual exercise. DOMS was induced by 50 maximal isokinetic eccentric elbow flexion contractions. Strength parameters, pain, arm circumference, and relaxed arm angle (RANG) were measured at 48, 72, and 168 h post exercise. Cortisol, creatine kinase (CK), interleukin-6 (IL-6), tumor necrosis factor (TNFalpha), malondialdehyde (MDA), and serum iron were measured before supplementation, after supplementation, and post exercise. RESULTS: Significant decreases were observed in RANG and strength 48 h postexercise among all groups, and there were significant increases in pain and arm circumference. There were no significant changes among all groups from baseline at 168 h (7 d) post exercise. There were no significant treatment effects between groups for the physical parameters or for cortisol, CK, IL-6, TNFalpha, MDA, or serum iron. CONCLUSION: These data indicate FO or ISO, at the doses supplemented, were not effective in ameliorating DOMS with the above-cited protocol.     

Effect of exercise during the follicular and luteal phases on indices of oxidative stress in healthy women

PURPOSE: Eleven healthy nonsmoking women (24+/-1.1 yr) exercised for 30 min at 75-80% VO2max during the follicular (F) and luteal (L) phases of their menstrual cycle to determine whether menstrual phase influenced indices of oxidative stress. METHODS: Subjects completed the exercise in a randomized order. Subjects reported between 0800 and 0900 in a postabsorptive state, rested for 15-30 min, and had a venous blood sample obtained by Vacutainer before and after exercise. RESULTS: Resting estradiol was 54.4+/-12.0 pg.mL(-1) for F phase and was significantly higher in L phase (147.2+/-25.5 pg.mL(-1)). Plasma malondialdehyde and thiobarbituric acid substances were no different before and after exercise independent of menstrual cycle phase. No differences in resting blood total glutathione (TGSH), oxidized glutathione (GSSG), and reduced glutathione (GSH) were evident comparing the F and L phases. After exercise, TGSH decreased (P = 0.03) but reached significance only in the F phase = 8.1 %(P = 0.04), L phase = 2.5% (P = 0. 15). Exercise increased GSSG 10.5% in F (P = 0.15) and 27.8% in L phases(P = 0.01). GSH decreased after exercise independent of menstrual phase (F = 17%, L = 16%, P = 0.01). CONCLUSION: These data suggest that 30 min of moderate-intensity exercise in female subjects can result in mild oxidative stress as indicated by blood glutathione status and that menstrual cycle phase has minimal influences on these exercise responses.     

Vitamin E supplementation attenuates leakage of enzymes following 6 successive days of running training

The purpose of this study was to examine whether vitamin E supplementation in humans would attenuate an increase of serum enzymes as an indirect marker of muscle damage following a sudden large increase in the running distance in a 6-day running training or not. A randomized and placebo-controlled study was carried out on fourteen male runners who were supplied vitamin E (alpha-tocopherol 1200 IU x day(-1); E) or placebo (P) 4 weeks prior to (T1) and during 6 successive days of running training (48.3 +/- 5.7 km x day(-1), means +/- SD). Resting venous blood samples were obtained before maximal treadmill running, at T1, the day immediately before (T2), the next day (T3), and three weeks (T4) after the running training. Serum levels of alpha-tocopherol, lipid peroxidation products (thiobarbituric acid; TBA), creatine kinase (CK), lactate dehydrogenase (LDH), and LDH isozyme 1-5 were quantitatively analyzed. No significant difference was found in maximal oxygen uptake (VO2max) and maximal heart rates following the exhaustive exercise between the P and E group during the experiments. Vitamin E supplementation significantly increased serum alpha-tocopherol (p<0.001) and decreased TBA levels (p < 0.001) compared with pre-supplementation levels. Although serum CK and LDH activities increased significantly at T3 in either group, significantly lower CK (p < 0.05) and LDH (p < 0.001) levels were observed in the E group compared with the P group. The ratio of LDH1 to LDH2 (LDH1/LDH2) decreased significantly at T3 in either group compared with the T1 levels, since there was no significant difference in the LDH1/LDH2 between the P and E group throughout the experiments. These results indicate that vitamin E supplementation can reduce the leakage of CK and LDH following 6 successive days of endurance running. The protective effect of vitamin E against free radicals probably inhibits free-radical-induced muscle damage caused by a sudden large increase in the running distance.     

Effect of vitamin B-6 supplementation on fuels, catecholamines, and amino acids during exercise in men

PURPOSE: In two separate but identical studies, the effect of vitamin B-6 supplementation was examined on plasma energy substrates, catecholamines, and 13 amino acid concentrations during exercise. METHODS: Eleven trained men performed two separate exhaustive exercise tests at 71.0+/-4.6% VO2max during two separate 9-d controlled diet periods. Exercise test 1 (T1C) occurred following a control diet, and test 2 (T2B6) occurred following a vitamin B-6 supplemented diet (20 mg PN.d(-1)). Blood was drawn pre, during (60 min), post, and post-60 min of exercise, and plasma was analyzed for glucose, lactate, glycerol, free fatty acids (FFA), catecholamines (N = 5), and amino acids (N = 5). RESULTS: Mean FFA concentrations changed over time in both tests (P < 0.001) and were lower in T2B6 compared to T1C at pre (P = 0.03), during (P = 0.05), and post-60 min (P = 0.04) of exercise. Mean lactate, glycerol, and catecholamine concentrations only changed over time (P < 0.0001). The only significant changes in amino acid concentrations were for lower tyrosine (P = 0.007) and methionine (P = 0.03) concentrations in T2B6 relative to TIC at post-60 min of exercise and postexercise, respectively. No differences were observed in exercise times to exhaustion between TIC (108+32.6 min) and T2B6 (109+51.2 min). CONCLUSIONS: These results indicate that vitamin B-6 supplementation can alter plasma FFA and amino acid concentrations during exhaustive endurance exercise without affecting endurance.     

补锌对耐力训练、力竭运动大鼠腓肠肌超氧化物岐化酶、谷胱甘肽过氧化物酶、总抗氧化能力以及Bax、Bcl-2 mRNA的影响

目的:探讨补锌对耐力训练、力竭运动大鼠腓肠肌超氧化物岐化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px,简称GPX)、总抗氧化能力(T-AOC)、细胞凋亡诱导和阻遏分子(Bax,Bcl-2)mRNA的影响。方法:将32只雄性SD大鼠随机分成对照组、耐力训练组、耐力训练补锌组和一次性力竭运动补锌组4组,每组8只。补锌方法为在饮用水中溶入ZnSO4.7H2O,[Zn]=227 mg/L。耐力训练组和耐力训练补锌组进行6周游泳耐力训练,每周6天。6周训练结束24小时后取材。一次性力竭运动组取材当日在同一泳池每隔15 min被放入2只大鼠,进行无负重游泳至力竭后取材。测定大鼠腓肠肌SOD、GPX、T-AOC活性,Bax、Bcl-2 mRNA表达。结果:耐力训练补锌组大鼠腓肠肌SOD活性显著高于对照组(P<0.05),GPX活性显著高于对照组和耐力训练组(P<0.05)。力竭运动补锌组大鼠腓肠肌GPX和T-AOC活性显著高于对照组(P<0.05)。耐力训练补锌组大鼠腓肠肌Bax mRNA表达显著低于对照组和耐力训练组(P<0.05),Bcl-2 mRNA表达显著高于对照组和耐力训练组(P<0.05)。力竭运动补锌组大鼠腓肠肌Bax,Bcl-2 mRNA表达均显著高于对照组(P<0.05)。结论:耐力训练提高大鼠腓肠肌GPX活性,增加Bcl-2 mRNA表达,降低大鼠腓肠肌Bax mRNA表达,补锌效果更明显。一次性力竭运动补锌提高大鼠腓肠肌GPX活性和T-AOC活性,增加腓肠肌Bcl-2 mRNA表达,但对Bax mRNA表达影响不明显。     

Effects of vitamin E supplementation on oxidative stress at rest and after exercise to exhaustion in athletic students

AIM: The purpose of this study is to determine the effect following exercise to exhaustion of vitamin E supplementation on oxidative stress in athletic students. METHODS: Twenty male students voluntarily participated in the study and were randomly assigned (double blind) to either a vitamin E (daily dose of 450 mg of a-tocopherol for a period of 8 weeks) or a placebo group (took capsules containing 450 mg of lactose for 8 weeks). Before and after 8 weeks blood samples were collected at rest and after exercise to exhaustion. Oxidative stress markers were malondialdehyde (MDA), carbonylated proteins (CP) and creatine kinase (CK). Also, the effect of vitamin E on ergometer cycling time, as an example of endurance performance, was evaluated. RESULTS: ANOVA and independent t-tests indicated that vitamin E supplementation did not significantly change (P > 0.05) MDA, CP and CK values at rest, after exercise to exhaustion, and cycling time, but plasma volume after exercise to exhaustion significantly decreased (P < 0.05). CONCLUSIONS: Although vitamin E supplementation had no effect on exercise performance or capacity in athletic students, further investigation is required using larger numbers of subjects and measures of vitamin E before unequivocal conclusion can be stated.     

Effect of fish oil supplementation and exercise on serum lipids and aerobic fitness

The effects of fish oil supplementation and exercise were investigated in healthy, previously sedentary males, ages 19-34. Thirty-two subjects were assigned to four groups: control (C), fish (F), exercise (E), fish and exercise (FE). The fish groups consumed 4 g.d-1 of omega-3 fatty acids. The exercise groups performed aerobic exercise for one hour three per week. The study was conducted for 10 weeks with pre and post values obtained for cholesterol, triglycerides, HDL-cholesterol, LDL-cholesterol, maximal oxygen consumption (VO2max), ventilatory anaerobic threshold (VAT), percent body fat, and dietary composition of macronutrients and polyunsaturated to saturated fat (P:S) ratio. No significant differences were noted between groups for any of the blood lipid values, percent body fat or dietary variables. VO2max and VAT did exhibit significant changes among groups. VO2max was greater for the exercise groups (E, FE) as compared to the control group (p less than 0.05). E, but not FE, was significantly greater than F. VAT was significantly greater in F, E, and FE as compared to controls, however the control's VAT decreased slightly. The slight improvement, although statistically non-significant, in VO2max and VAT by the F group requires further study. This data indicates an improvement in aerobic metabolism from aerobic exercise, alone or in combination with fish oil, compared to controls.     

Effect of vitamin C supplementation on lipid peroxidation, muscle damage and inflammation after 30-min exercise at 75% VO2max

AIM: Hypothetically, supplementation with the antioxidant vitamins C could alleviate exercise-induced lipid peroxidation. The purpose of this study was to evaluate the effect of vitamin C supplementation on exercise-induced lipid peroxidation, muscle damage and inflammation. METHODS: Sixteen healthy untrained male volunteers participated in a 30-min exercise at 75% Vo2max. Subjects were randomly assigned to one of two groups: 1) placebo and 2) vitamin C (VC: 1 000 mg vitamin C). Blood samples were obtained prior to supplementation (baseline), 2 h after supplementation (immediately pre-exercise), post-exercise, 2 and 24 h after exercise. Plasma levels of VC, total antioxidant capacity (TAC), creatine kinase (CK), malondealdehyde (MDA), total leukocytes, neutrophils, lymphocytes, interleukin-6 (IL-6) and cortisol were measured. RESULTS: Plasma vitamin C concentrations increased significantly in the VC in response to supplementation and exercise (P<0.05). TAC decreased significantly in Placebo group 24 h after exercise compared to pre-exercise (P<0.05). Although MDA levels were similar between groups at baseline, it increased significantly 2 h after exercise only in the Placebo group (P<0.05). CK increased immediately and 2 h after exercise in both groups and 24 h after exercise only in placebo group compared to pre-exercise (P<0.05). Markers of inflammation (total leukocyte counts, neutrophil counts and IL-6) were increased significantly in response to the exercise (P<0.05). In VC group, there was significant increase in lymphocyte counts immediately after exercise compared with pre-exercise (P<0.05). Serum cortisol concentrations significantly declined after supplementation compared with baseline (P<0.05) as well as declined 2 and 24 h after exercise compared with immediately after exercise in VC group (P<0.05). CONCLUSION: VC supplementation prevented endurance exercise-induced lipid peroxidation and muscle damage but had no effect on inflammatory markers.     

高压氧对急性运动大鼠腓肠肌细胞凋亡的影响

目的:探讨高压氧对急性运动大鼠腓肠肌Caspase 3、Bcl-2蛋白表达与细胞凋亡的影响。方法:选用32只健康成年雄性大鼠,随机分为安静对照组、安静高压氧组、急性力竭运动组和急性运动高压氧恢复组4组。安静高压氧组于采样前应用高压氧治疗60 min;急性力竭运动组与急性运动高压氧恢复组进行坡度为10%、速度25 m/min的跑台运动至力竭,其中急性运动高压氧恢复组运动后应用高压氧恢复60 min。对4组大鼠腓肠肌进行HE染色,应用免疫组化技术测定Bcl-2蛋白与Caspase 3蛋白表达。结果:急性力竭运动组大鼠腓肠肌细胞出现凋亡的形态结构改变,急性运动高压氧恢复组细胞凋亡现象较急性力竭运动组明显减少;急性力竭运动组和急性运动高压氧恢复组Bcl-2蛋白阳性率显著高于安静对照组,急性运动高压氧恢复组Bcl-2蛋白阳性率高于急性力竭运动组;急性力竭运动组和急性运动高压氧恢复组大鼠腓肠肌Caspase 3蛋白阳性率显著高于安静对照组,急性运动高压氧恢复组Caspase 3蛋白阳性率显著低于急性力竭运动组。结论:高压氧疗法能促进急性力竭运动大鼠腓肠肌Bcl-2蛋白表达,抑制Caspase 3蛋白表达,减少腓肠肌的细胞凋亡。