Exercise-induced Oxidative Stress Research Articles

Novel Humanized G6PD Deficient Mice Reveal Mechanisms of Increased Tolerance to Exercise As Gleaned By Multi-Omics in Models of Critical Speed

INTRODUCTION: Glucose-6-phosphate-dehydrogenase (G6PD) deficiency is the most common enzymatic deficiency in humans, affecting ~500 million people or ~6% of mankind. G6PD is the rate limiting enzyme of the pentose phosphate pathway (PPP), the main antioxidant pathway in mature red blood cells (RBCs). Activation of the PPP generates NADPH, an essential reducing equivalent for antioxidant metabolism that protects against intra- and extra-vascular hemolysis in response to oxidant stress. Impaired G6PD activity makes RBCs susceptible to hemolysis induced by oxidant challenges. Exercise-induced oxidant stress is a well-established concept in the field of physiology. Individuals with G6PD deficiency are recommended to refrain from strenuous exercise, as they are deemed to be at increased risk for hemolytic events in response to exercise-induced oxidant stress. While biochemically sound, this rationale has never been tested mechanistically, owing to ethical and technical limitations. As such, knowledge is limited regarding molecular impacts of exercise activity in G6PD deficient individuals. METHODS: Here we generated novel humanized mouse models carrying either (i) human canonical G6PD (normal activity), or two of the most common G6PD variants (ii) African (V68M - < 10% residual enzymatic activity) or (iii) Mediterranean (S188F - <1% residual enzymatic activity). We leveraged these mouse models to assess critical speed (CS), a functional measurement of the speed-to-duration relationship. To expand the molecular resolution of genetically associated adaptations to exercise, CS tests were combined with measurements of hemodynamics - including cardiac output, imaging (e.g., scanning electron microscopy of RBCs before and after exercise) and multi-omics (mass spectrometry-based metabolomics, lipidomics and proteomics) characterization of plasma, RBCs, and multiple tissue matrices including liver, heart, kidney, lung, spleen, and muscles (gastrocnemius and soleus). RESULTS: First of all, we confirmed a significant decrease in G6PD activity in RBCs from mice carrying the African and Mediterranean variants ( Figure 1). Unexpectedly, G6PD deficient mice showed ~10% faster CS compared to mice carrying the canonical human G6PD (p<0.0001 and p<0.02, Figure 1). While scanning electron microscopy showed differences before and after exercise, with accumulation of reversibly modified morphologies across all groups after the run, no significant differences were observed across groups. No significant changes in hemolysis markers were observed in plasma samples after exercise, neither at the metabolic (e.g., heme catabolites) or proteomics level (e.g., hemoglobin chains, RBC-derived proteins). Within hemodynamics, the hG6PD Med- mice are showing a higher efficiency in their cardiac function through cardiac function (p<0.005 - Figure 1). Pathway analysis of metabolomics data generated from RBC and plasma fractions showed significant decreases in arginine metabolism, increased glycolysis, and elevated Krebs cycle intermediates, in addition to expected differences in PPP. Specifically, in hG6PD A- RBC acylcarnitines accumulate after running. In hG6PD Med-, there are clear left ventricular differences highlighted in energy metabolism ( Figure 1). Multiomics analyses identified five major tissue clusters between heart, muscle, liver, kidney, and spleen, with G6PD function having the most significant metabolic impact on liver and soleus. RBC proteomics results highlighted deceased ferroportin (key iron transporter) in both the deficient groups, with markedly significant changes in the hG6PD Med- (p<0.0001). CONCLUSION: Novel humanized G6PD deficient mice maintain faster CS compared to mice. Omics approaches afford the opportunity to identify metabolic correlates to measurements of performance in relevant animal models, such as the CS model, which offer expanded mechanistic understanding of molecular bases of CS and the associated impact of G6PD deficiency. Our results not only challenge the assumption that exercise-induced oxidant stress predisposes the ~500M individuals with G6PD deficiency worldwide to increased hemolytic propensity, but rather indicate a metabolic advantage of functional polymorphisms to G6PD with respect to exercise performance, an observation that could contribute explaining the prevalence of such mutation in human populations.

Betalains Alleviate Exercise-Induced Oxidative Stress, Inflammation, and Fatigue and Improve Sports Performance: an Update on Recent Advancement.

Beetroot juice is a popular natural food supplement commonly consumed for its health and ergogenic benefits. It contains an abundance of phytochemical compounds, which have been shown to enhance sports endurance and recovery. Among them, nitrate is well-studied and known for improving performance during exercise. On the other hand, betalains, the bioactive pigment, have shown various biological activities including antioxidant, anti-inflammatory, and anti-hypertensive, which may improve exercise performance and post-exercise recovery. Additionally, free radical scavenging activities of betalains could increase nitric oxide availability in the blood, thereby improving blood flow and oxygen supply during strenuous exercise. This review article provides a critical discussion of the non-pathological conditions induced by prolonged or strenuous exercise and betalains' potential in reducing such conditions including muscle damage, inflammation, and fatigue. Additionally, the real-time application of betalains as an ergogenic compound in competitive athletes has been discussed. Finally, future directions and conclusions on the potential of betalains as a natural ergogenic aid in sport endurance are outlined. Betalains in beetroot are the major water-soluble nitrogen-containing pigment possessing high antioxidant, anti-inflammatory, and anti-fatigue activities. Betalain supplementation could alleviate exercise-induced oxidative stress, inflammation, and fatigue in competitive athletes. Betalains have the potential to become a natural ergogenic aid or nutraceutical compound for sports people during exercise and competitive performance.

Antioxidant effect of omega-3 fatty acids on exercise-induced oxidative stress in rats.

The aim of this study is to examine the effects of omega-3 supplementation on Catalase (CAT) activity, Malondialdehyde (MDA), advanced oxidation protein products (AOPP) and reduced glutathione (GSH) levels in long-term aerobic exercises in rats. 28 male Wistar albino rats (8 weeks old, 220-350 g body weight) were included in the study. The rats were given treadmill exercise for 20 minutes at an average speed of 15 cm/s, 5 days a week, for 8 weeks. The experiment was terminated at the end of the eighth week. Blood samples were taken. CAT, MDA, AOPP and GSH analyses were performed. SPSS v. 21 package program was used in the analysis of the data. The distribution of the data was examined with the normality homogeneity test, and it was determined that it was a normal distribution. As a result, the One-Way ANOVA test, one of the parametric tests, was used. Tukey test was used to determine the difference between groups. Significance levels were evaluated as (p < 0.05). Statistical analysis showed a statistically significant difference between groups in CAT, MDA and GSH levels (p < 0.05), while there were no differences between the groups in AOPP levels (p > 0.05). In the conclusion of the study, it was determined that omega-3 supplementation caused a decrease in MDA level, an increase in CAT activity and GSH level in rats exposed to chronic long-term exercise. Thus, it can be said that omega-3 supplementation in chronic long-term exercise will provide antioxidant protection against potential oxidative damage.

Effects of maslinic acid supplementation on exercise-induced inflammation and oxidative stress in water polo athletes: A randomized, double-blind, crossover, and placebo-controlled trial.

Olive fruit is rich in bioactive pentacyclic triterpenoids, primarily maslinic acid (MA). Previous studies have demonstrated that MA exhibits anti-inflammatory and anti-oxidative effects; however, it is unclear whether MA intake during training inhibits perceptual fatigue and muscle soreness in athletes. This study analyzed the effects of MA supplementation during athletic training on perceptual fatigue and muscle soreness. This randomized, double-blind, cross-over, and placebo-controlled trial involved 12 young, healthy male water polo athletes. After daily training for seven days, they ingested either olive fruit extract, containing 60 mg/day MA, or a placebo. We measured perceptual fatigue and muscle soreness during the intervention using a visual analog scale and inflammatory and oxidative stress-related proteins. Perceptual fatigue and muscle soreness and the area under the curve during the training period were significantly lower (main effect of MA; P < 0.05) following MA supplementation than those for the placebo. MA supplementation during training lowered perceptual fatigue and muscle soreness by decreasing inflammatory factors in water polo athletes. Additionally, we examined the detailed mechanism of MA, added the participant's serum to the culture medium at a 10% concentration to determine inflammation- and oxidative stress-related intracellular signals. Skeletal muscle cells (C2C12) cultured with MA-conditioned serum before and after intervention also suppressed expression of inflammation and oxidative stress-related proteins. These findings suggest that MA intake not only reduces perceptual fatigue and muscle soreness but also decreases inflammation and oxidative stress in the blood and skeletal muscle.

Effects of L-Carnitine Intake on Exercise-Induced Muscle Damage and Oxidative Stress: A Narrative Scoping Review.

Exercise-induced muscle damage results in decreased physical performance that is accompanied by an inflammatory response in muscle tissue. The inflammation process occurs with the infiltration of phagocytes (neutrophils and macrophages) that play a key role in the repair and regeneration of muscle tissue. In this context, high intensity or long-lasting exercise results in the breakdown of cell structures. The removal of cellular debris is performed by infiltrated phagocytes, but with the release of free radicals as collateral products. L-carnitine is a key metabolite in cellular energy metabolism, but at the same time, it exerts antioxidant actions in the neuromuscular system. L-carnitine eliminates reactive oxygen and nitrogen species that, in excess, alter DNA, lipids and proteins, disturbing cell function. Supplementation using L-carnitine results in an increase in serum L-carnitine levels that correlates positively with the decrease in cell alterations induced by oxidative stress situations, such as hypoxia. The present narrative scoping review focuses on the critical evaluation of the efficacy of L-carnitine supplementation on exercise-induced muscle damage, particularly in postexercise inflammatory and oxidative damage. Although both concepts appear associated, only in two studies were evaluated together. In addition, other studies explored the effect of L-carnitine in perception of fatigue and delayed onset of muscle soreness. In view of the studies analyzed and considering the role of L-carnitine in muscle bioenergetics and its antioxidant potential, this supplement could help in postexercise recovery. However, further studies are needed to conclusively clarify the mechanisms underlying these protective effects.

Training in a Hot Environment Fails to Elicit Changes in the Blood Oxidative Stress Response.

Environmental temperature can impact exercise-induced blood oxidative stress; however, the effects of heat acclimation on this response have not been fully elucidated. The purpose of the study was to investigate the effects of hot (33°C) and room temperature (20°C) environments on post-exercise blood oxidative stress responses following 15 temperature acclimation sessions. Untrained participants (n = 38, 26 ± 7 years, VO2peak = 38.0 ± 7.2 years) completed 15 temperature acclimation sessions of a cycling bout at an intensity perceived as "hard" in either a hot (33°C) or room temperature (20°C) environment. Pre and post acclimation exercise tolerance trials were conducted, which involved cycling at 50% Wpeak for one hour. Blood sampling occurred before exercise, immediately after, two hours, and four hours after the exercise tolerance trials. Blood samples were analyzed for oxidative stress markers including lipid hydroperoxides, 8-isoprostanes, protein carbonyls, 3-nitrotyrosine, ferric-reducing ability of plasma, and Trolox-equivalent antioxidant capacity. Exercise-dependent increases were observed in lipid hydroperoxides, Trolox-equivalent antioxidant capacity, and ferric-reducing ability of plasma (p < 0.001). Considering exercise-induced elevations in markers of blood oxidative stress, there were no differences observed between environmental temperatures before or after the acclimation training period.

Changes in Blood Markers of Oxidative Stress, Inflammation and Cardiometabolic Patients with COPD after Eccentric and Concentric Cycling Training.

Chronic obstructive pulmonary disease (COPD) patients manifest muscle dysfunction and impaired muscle oxidative capacity, which result in reduced exercise capacity and poor health status. This study examined the effects of 12-week eccentric (ECC) and concentric (CONC) cycling training on plasma markers of cardiometabolic health, oxidative stress, and inflammation in COPD patients. A randomized trial in which moderate COPD was allocated to ECC (n = 10; 68.2 ± 10.0 year) or CONC (n = 10; 71.1 ± 10.3 year) training groups. Participants performed 12-week ECC or CONC training, 2-3 sessions per week, 10 to 30 min per session. Before and after training, peak oxygen consumption, maximal power output (VO2peak and POmax), and time-to-exhaustion (TTE) tests were performed. Plasma antioxidant and oxidative markers, insulin resistance, lipid profile, and systemic inflammation markers were measured before and after training at rest. VO2peak, POmax and TTE remained unchanged after ECC and CONC. CONC induced an increase in antioxidants (p = 0.01), while ECC decreased antioxidant (p = 0.02) markers measured at rest. CONC induced lesser increase in oxidative stress following TTE (p = 0.04), and a decrease in insulin resistance (p = 0.0006) compared to baseline. These results suggest that CONC training induced an increase in insulin sensitivity, antioxidant capacity at rest, and lesser exercise-induced oxidative stress in patients with moderate COPD.

The effect of pre-exercise alkalosis on lactate/pH regulation and mitochondrial respiration following sprint-interval exercise in humans.

Purpose: The purpose of this study was to evaluate the effect of pre-exercise alkalosis, induced via ingestion of sodium bicarbonate, on changes to lactate/pH regulatory proteins and mitochondrial function induced by a sprint-interval exercise session in humans. Methods: On two occasions separated by 1week, eight active men performed a 3 × 30-s all-out cycling test, interspersed with 20min of recovery, following either placebo (PLA) or sodium bicarbonate (BIC) ingestion. Results: Blood bicarbonate and pH were elevated at all time points after ingestion in BIC vs PLA (p < 0.05). The protein content of monocarboxylate transporter 1 (MCT1) and basigin (CD147), at 6h and 24h post-exercise, and sodium/hydrogen exchanger 1 (NHE1) 24h post-exercise, were significantly greater in BIC compared to PLA (p < 0.05), whereas monocarboxylate transporter 4 (MCT4), sodium/bicarbonate cotransporter (NBC), and carbonic anhydrase isoform II (CAII) content was unchanged. These increases in protein content in BIC vs. PLA after acute sprint-interval exercise may be associated with altered physiological responses to exercise, such as the higher blood pH and bicarbonate concentration values, and lower exercise-induced oxidative stress observed during recovery (p < 0.05). Additionally, mitochondrial respiration decreased after 24h of recovery in the BIC condition only, with no changes in oxidative protein content in either condition. Conclusion: These data demonstrate that metabolic alkalosis induces post-exercise increases in several lactate/pH regulatory proteins, and reveal an unexpected role for acidosis in mitigating the loss of mitochondrial respiration caused by exercise in the short term.

Polyphenol Supplementation and Antioxidant Status in Athletes: A Narrative Review

Antioxidants in sports exercise training remain a debated research topic. Plant-derived polyphenol supplements are frequently used by athletes to reduce the negative effects of exercise-induced oxidative stress, accelerate the recovery of muscular function, and enhance performance. These processes can be efficiently modulated by antioxidant supplementation. The existing literature has failed to provide unequivocal evidence that dietary polyphenols should be promoted specifically among athletes. This narrative review summarizes the current knowledge regarding polyphenols' bioavailability, their role in exercise-induced oxidative stress, antioxidant status, and supplementation strategies in athletes. Overall, we draw attention to the paucity of available evidence suggesting that most antioxidant substances are beneficial to athletes. Additional research is necessary to reveal more fully their impact on exercise-induced oxidative stress and athletes' antioxidant status, as well as optimal dosing methods.

Impact of Exercise Intensity on Systemic Oxidative Stress, Inflammatory Responses, and Sirtuin Levels in Healthy Male Volunteers.

Exercise can induce anti-inflammatory and antioxidant effects, for which regulation of sirtuins (SIRTs) may be a major consideration for exercise prescription. The purpose of this study was to investigate the effects of acute aerobic exercise, in particular its intensity, on systemic oxidative stress, inflammatory responses, and SIRT levels. Twenty healthy, untrained males were recruited and randomly assigned to moderate-intensity (MI, 65% VO2max, n = 10) and high-intensity (HI, 85% VO2max, n = 10) exercise. Blood samples were obtained pre-, immediately post-, and 1 h post-exercise for measurements of malonaldehyde (MDA), superoxide dis-mutase (SOD), interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, SIRT-1, SIRT-2, and SIRT-3. Overall, MDA, SOD, IL-6, SIRT-1, and SIRT-3 levels were significantly increased at post-exercise compared with pre-exercise regardless of exercise intensity (p < 0.05). The HI group had significantly higher MDA, SOD, and IL-6 levels than the MI group at post-exercise (p < 0.05), whereas no significant differences were observed in the IL-1β, TNF-α, and SIRT-2 levels (p > 0.05). Altogether, these findings suggest that exercise-induced oxidative stress and inflammatory responses may be dependent on exercise intensity. Moreover, activation of inflammatory cytokines and SIRT family members may be dependent on the intensity of the exercise.

Exercise-induced Oxidative Stress During Exercise And Recovery In Hot Condition

Acute exercise of sufficient intensity and duration can result in oxidative stress (OS), characterized by elevated blood OS biomarkers. Unfortunately, the time course for the change in OS and its recovery (RC) has not been adequately determined in most studies. PURPOSE: This study investigated the pattern change in blood OS biomarkers (low density lipoproteins oxidized (LDLox) and glutathione ratio (oxidized glutathione (GSSG) to total glutathione (TGSH) during a 1 h bout of cycling and a 1 h RC period, compared to a rest condition. It was hypothesized that the blood OS biomarkers would be elevated within the first 30 min of exercise based on the predicted intensity with the OS biomarkers returning to baseline during RC. METHODS: Ten males (mean(SD)); age,24.4 (1) yrs; mass, 75.3 (2.1) kg; height 175.9 (1) cm; VO2max, 50.0 (1.8) ml·kg-1·min-1) arrived at 1800 h on two occasions and completed; an exercise (Ex) (70-75% max power output) or rest (RE) condition in a hot environment (40oC and 30% relative humidity), in a randomized order. Blood was sampled every 15 min during EX and at min 15, 30 and 60 mins during RC. Plasma LDLox and both reduced (GSH) and oxidized (GSSG) forms of glutathione status were assessed. Repeated measures ANOVAs (2 conditions x 4 times [EX] and 2 conditions x 4 times [RC]) determined if differences in LDLox, and GSSG/TGSH ratio occurred with an alpha set a priori p < .05. RESULTS: Mean HR for RE was 73 ± 3 bpm vs 165 ± 3 for EX overtime. Mean cycling power output was 151 ± 9 W during EX. There was no main effect for condition (p = 0.054) or time (p = 0.061) or interaction (time by condition) effect (p = 0.074) for LDLox during EX. The GSSG/TGSH ratio increased at 30 minutes regardless of condition (12.5% compared to 5% at 0 minutes in chamber). The GSSG/TGSH ratio had a main effect for time to increase at 60 min RC independent of condition (p = 0.02). CONCLUSIONS: The results did not support our hypothesis of an exercise-induced OS. Our findings were likely impacted by 1) the environmental conditions inducing a high heat stress at rest, 2) delayed recovery due to the high heat stress in combination with dehydration during recovery, and 3) and small sample size which could not overcome the large interindividual variability in LDLox values.

Salivary Concentrations Of Lipid Peroxidation Products Represent Plasma Concentrations In Athletes Before And After Exercise

Many types of muscular exercise promote the production of reactive oxygen species and result in oxidative stress, as evidenced by increased levels of lipid peroxidation products in both blood plasma and saliva. PURPOSE: To assess the agreement between quantitative measurements of lipid peroxidation products in plasma and saliva of athletes at rest and following the Åstrand-Rhyming test. METHODS: 20 elite athletes, aged 18-22 years, participated in the study. Athletes underwent the Åstrand-Rhyming cycle ergometer test. Blood and saliva samples were collected before (pre-exercise) and immediately after the exercise (postexercise). Diene conjugates (DC), triene conjugates (TC) and Schiff bases (SB) were photometrically determined. Optical densities were measured at 220 nm (absorption of isolated double bonds), 232 nm (absorption of DC), 278 nm (absorption of TC), and 400 nm (absorption of SB). Assumption of normality was verified using the Shapiro-Wilk test. Since all data were normally distributed, comparisons were made using paired Student’s t-test. Bland-Altman (B&A) analysis was applied. RESULTS: DC levels were elevated in plasma (0.17 + 0.02 vs. 0.19 + 0.02 a.u., p < 0.001) and saliva (0.17 + 0.02 vs. 0.19 + 0.02 a.u., p < 0.01) in response to exercise, as were the plasmatic (0.12 + 0.04 vs. 0.14 + 0.04 a.u., p < 0.05) and salivary (0.11 + 0.03 vs. 0.14 + 0.03 a.u., p < 0.05) TC concentrations. SB levels were also significantly higher at postexercise compared to pre-exercise in both plasma (21.46 + 4.63 vs. 31.14 + 6.25 a.u., p < 0.001) and saliva (20.83 + 4.06 vs. 30.19 + 6.45 a.u., p < 0.001). The bias calculated for DC (0.005, pre-exercise; 0.004, postexercise), TC (0.002, pre-exercise; 0.004, postexercise) and SB (0.64, pre-exercise; 0.95, postexercise) using the B&A statistics was not significant both at pre-exercise and at postexercise because the line of equality was within the confidence interval of the mean difference. All of the data points lay within the respective agreement limits. CONCLUSIONS: High agreement between quantitative measurements of plasmatic and salivary DC, TC and SB was detected both at rest and following the Åstrand-Rhyming test. Saliva may be considered as an attractive option for identifying exercise-induced oxidative stress in athletes.

Effects Of Astaxanthin On Aerobic Capacity And Antioxidant Enzymes For Team Sport Athletes

PURPOSE:Frequent competition can cause oxidative stress, leading to fatigue and a decrease in aerobic capacity. Antioxidant supplementation are commonly consumed to minimize exercise-induced oxidative stress, with the intention of enhancing recovery and improving performance. Thus, this study aims to determine 4 weeks supplement of astaxanthin on aerobic capacity, the recovery of blood lactic acid and antioxidant enzymes activity in team sports athletes during season training. METHODS:Twenty team sport varsity athletes (basketball: n = 10, football: n = 10) were randomly assigned in double-blind fashion to one of two treatment groups. The astaxanthin group (AST, n = 10) was supplemented 12 mg of astaxanthin for 4 weeks, and the placebo group was supplemented with olive oil capsules of the same dose. The incremental exercise test was performed before and after the supplementation, respectively. Fingertip blood was collected at 3, 6 and 9 min after exercise, blood lactic acid were analysed that day and calculated removal rate. Fasting venous blood was collected before and 12 h after incremental exercise test, and the activity of SOD, CAT and GSH-Px were measured. Performance indicators comparisons were made using independent sample T test and paired sample T test. Antioxidant enzymes activity comparisons were made using two-way ANOVA repeated measures. RESULTS:There were no significant changes in exhaustion time and VO2max in AST group, while the exhaustion time (17.22 ± 1.64 vs 15.53 ± 1.70 min P < 0.01) and VO2max (49.14 ± 4.41 vs 44.57 ± 3.87 ml/min/kg, P < 0.05) in PLA group were significantly decreased; The blood lactic acid removal rate had no significant change in two groups(P > 0.05);There was no significant change in the activity of antioxidant enzymes before exercise, but both the CAT (7.93 ± 0.83 vs. 2.91 ± 0.55 U/ml, P < 0.05)and GSH-Px(181.40 ± 9.49 vs. 155.39 ± 8.03 U/ml, P < 0.05) activity recovered more quickly at 12 h after exhaustive exercise than 0-week in AST group. CONCLUSIONS:4 weeks of training during the season can lead to a decline in aerobic capacity in team sport athletes, but intake of astaxanthin can help speed up CAT and GSH-Px activity recovery after exhaustive exercise, then enhancing recovery and improving performance. Supported by Herbalife Winter Sports Nutrition Research Center

Effect of Tribulus terrestris L. supplementation on Exercise-Induced Oxidative Stress and Delayed Onset Muscle Soreness Markers: A Pilot Study

Tribulus terrestris L. contains compounds with antioxidant and anti-inflammatory properties, but its effects on exercise-induced oxidative stress and inflammatory responses are unclear. The aim of this study was to examine whether Tribulus terrestris L. supplementation can attenuate oxidative stress and inflammatory responses to acute aerobic exercise and improve DOMS. In a randomized, double-blind, crossover design study, thirteen healthy men received either a daily supplement of Tribulus terrestris L. or a placebo for 4 weeks (2-week wash-out period between trials). Before and after the supplementation periods, participants performed an exercise test to exhaustion (75% VO2max). DOMS, thigh girth, and knee joint range of motion (KJRM) were assessed before and after the exercise (2, 24, and 48 h). Blood samples were analyzed for reduced (GSH) and oxidized (GSSG) glutathione, GSH/GSSG ratio, protein carbonyls, total antioxidant capacity, creatine kinase activity, white blood cell count, and TBARS. Acute exercise to exhaustion induced inflammatory responses and changed the blood redox status in both Tribulus and Placebo groups (p < 0.050). Tribulus terrestris L. improved GSH fall (p = 0.005), GSSG rise (p = 0.001) and maintained a higher level of GSH/GSSG ratio at the 2 h point (p = 0.034). TBARS were lowered, protein carbonyls, creatine kinase activity, and white blood cell count elevation diminished significantly (p < 0.050). Tribulus terrestris L. administration did not affect DOMS, thigh girth, or KJRM (p > 0.050). 4-weeks of Tribulus terrestris L. supplementation effectively attenuates oxidative stress responses but cannot improve DOMS.

Can Photobiomodulation Therapy (PBMT) Minimize Exercise-Induced Oxidative Stress? A Systematic Review and Meta-Analysis.

Oxidative stress induced by exercise has been a research field in constant growth, due to its relationship with the processes of fatigue, decreased production of muscle strength, and its ability to cause damage to the cell. In this context, photobiomodulation therapy (PBMT) has emerged as a resource capable of improving performance, while reducing muscle fatigue and muscle damage. To analyze the effects of PBMT about exercise-induced oxidative stress and compare with placebo therapy. Data Sources: Databases such as PubMed, EMBASE, CINAHL, CENTRAL, PeDro, and Virtual Health Library, which include Lilacs, Medline, and SciELO, were searched to find published studies. Study Selection: There was no year or language restriction; randomized clinical trials with healthy subjects that compared the application (before or after exercise) of PBMT to placebo therapy were included. Study Design: Systematic review with meta-analysis. Level of Evidence: 1. Data Extraction: Data on the characteristics of the volunteers, study design, intervention parameters, exercise protocol and oxidative stress biomarkers were extracted. The risk of bias and the certainty of the evidence were assessed using the PEDro scale and the GRADE system, respectively. Results: Eight studies (n = 140 participants) were eligible for this review, with moderate to excellent methodological quality. In particular, PBMT was able to reduce damage to lipids post exercise (SMD = −0.72, CI 95% −1.42 to −0.02, I2 = 77%, p = 0.04) and proteins (SMD = −0.41, CI 95% −0.65 to −0.16, I2 = 0%, p = 0.001) until 72 h and 96 h, respectively. In addition, it increased the activity of SOD enzymes (SMD = 0.54, CI 95% 0.07 to 1.02, I2 = 42%, p = 0.02) post exercise, 48 and 96 h after irradiation. However, PBMT did not increase CAT activity (MD = 0.18 CI 95% −0.56 to 0.91, I2 = 79%, p = 0.64) post exercise. We did not find any difference in TAC or GPx biomarkers. Conclusion: Low to moderate certainty evidence shows that PBMT is a resource that can reduce oxidative damage and increase enzymatic antioxidant activity post exercise. We found evidence to support that one session of PBMT can modulate the redox metabolism.

The effect of Tribulus terrestris supplementation on inflammation, oxidative stress, and performance of recreational runners: study protocol for a randomized placebo-controlled trial

BackgroundHigh intensity and endurance exercises lead to exercise-induced oxidative stress (EIOS), exercise-induced muscle damage (EIMD), and inflammation, which are the influencing factors on muscle soreness, localized swelling, and sports performance decrease. Therefore, the purpose of this study is to determine the effectiveness of Tribulus terrestris (TT) as an herbal supplement with antioxidant and anti-inflammatory properties on the nutritional, oxidative, inflammatory, and anti-inflammatory status, as well as the sports performance of recreational runners.Methods/designThis study is a double-blind, randomized, placebo-controlled trial, which will be conducted among recreational runners of Tabriz stadiums, Iran. Thirty-four recreational runners will be selected, and participants will be assigned randomly to two groups: to receive 500 mg TT supplement or placebo capsules twice daily for 2 weeks. Both groups will do high-intensity interval training (HIIT) workouts during the study. Baseline and post-intervention body composition, muscle pain, and aerobic and anaerobic performance will be assessed. In addition, assessment of malondialdehyde (MDA), total antioxidant capacity (TAC), total oxidant status (TOS), superoxide dismutase (SOD), glutathione peroxidase (GPx), uric acid (UA), 8-iso-prostaglandin F2α (8-iso-PGF2α), protein carbonyl (PC), catalase (CAT), glutathione (GSH), nitric oxide (NO), high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-α), creatine kinase (CK), myoglobin (MYO), lactate dehydrogenase (LDH), insulin-like growth factor-1 (IGF-1) irisin, cortisol, and brain-derived neurotrophic factor (BDNF) will be done during three blood samplings. Changes in oxidative stress, anti/inflammatory biomarkers, and sports performance will be assessed as primary outcomes.DiscussionThis study will be the first to assess the potential effects of TT on recreational runners. Our results will contribute to the growing body of knowledge regarding TT supplementation on the nutritional, oxidative, inflammatory, and anti-inflammatory status and sports performance in recreational runners.Trial registrationIranian Registry of Clinical Trials (www.irct.ir) (ID: IRCT20150205020965N8). Registration date: 13 February 2021.

Effects of Alkaline-Reduced Water on Exercise-Induced Oxidative Stress and Fatigue in Young Male Healthy Adults

Regular physical activity confers health benefits and improves the general quality of life. Recently, alkaline-reduced water (ARW) consumption has garnered increasing attention in the field of sports. ARW effectively inhibits the oxidative stress generated in cells during high-intensity exercises; however, whether it exerts similar effects during exhaustive exercises remains unknown. This study was designed as a randomized, controlled, crossover, double-blind clinical trial with a single intervention of ARW intake (pH 9.5, 10 mL/kg body weight) after intense exercise. The participants were divided into two groups, wherein they consumed either purified water (PW group) or ARW (ARW group). Blood samples were collected before exercise, immediately after exercise, and 15 min after drinking water. The serum levels of oxidative stress markers and fatigue markers were determined. The results showed that ROS (p &lt; 0.01) and NO levels (p &lt; 0.001) were significantly decreased after ARW intake, and the reduction was more pronounced than that in the PW group. Interestingly, the increase in GPx and MDA levels was mediated by ARW intake (both p &lt; 0.05) after exercise. The levels of fatigue markers, such as lactate (p &lt; 0.001), lactate dehydrogenase (p &lt; 0.001), and phosphate (p &lt; 0.001), were significantly reduced in both groups, with ARW intervention showing more decreased markers. The correlation analysis results showed that ARW may help maintain homeostatic conditions for ROS, antioxidant systems, and fatigue markers. These findings indicate that ARW consumption is effective in reducing oxidative stress and fatigue following exhaustive exercise and that ARW could be used as an antioxidant and anti-fatigue supplement after exhaustive physical exercise.

Antioxidants Supplementation During Exercise: Friends or Enemies for Cardiovascular Homeostasis?

Exercise is a preferred strategy for improving cardiac function, especially for patients with cardiovascular diseases. Increasing evidence indicates that oxidative stress is involved in exercise-induced cardioprotection, while the underlying mechanism remains unclear. Furthermore, the effect of antioxidant supplementation during or post-exercise still exists despite divergences. To explore the effect of oxidative stress and antioxidant supplementation on cardiovascular homeostasis during or post-exercise, we take insights into the progress of exercise-induced oxidative stress, antioxidant supplementation, and cardiovascular homeostasis. In particular, antioxidants such as vitamin C or E, gamma-oryzanol, and other natural antioxidants are discussed concerning regulating exercise-associated oxidative stress. Additionally, our present study reviewed and discussed a meta-analysis of antioxidant supplementation during exercise. Overall, we take an insight into the essential biological adaptations in response to exercise and the effects of antioxidant supplementation on cardiac function, which aid us in giving recommendations on antioxidant supplementation for exercisers and exercised people. A better understanding of these issues will broaden our knowledge of exercise physiology.

Effects of different-intensity exercise and creatine supplementation on mitochondrial biogenesis and redox status in mice.

Objective(s):Dietary supplementation combined with exercise may potentiate the beneficial effects of exercise by reducing exercise-induced oxidative stress and improving mitochondrial quality and capacity. In this study, the effects of creatine monohydrate (CrM) supplementation with low and high-intensity exercise on mitochondrial biogenesis regulators, Nrf2 anti-oxidant signaling pathway and muscle damage levels were investigated. Materials and Methods: Balb/c male mice were divided into six experimental groups: control, control+CrM, high-intensity exercise, high-intensity exercise+CrM, low-intensity exercise, and low-intensity exercise+CrM. Mice were given CrM supplementation and at the same time, low and high-intensity exercise was applied to the groups on the treadmill at 30min/5day/8week. Then, mitochondrial biogenesis marker (PGC-1α, NRF-1, TFAM), Nrf2 and HO-1 protein expressions, total oxidant-anti-oxidant status level, and histopathological changes were investigated in serum and muscle tissue. Results:Exercise intensity and CrM supplementation were found to be effective factors in mitochondrial biogenesis induction via the PGC-1α signaling pathway. Nrf2 and HO-1 protein levels increased with exercise intensity, and this result was directly related to serum oxidative stress markers. In addition, CrM supplementation was effective in reducing exercise-induced muscle damage. Conclusion:This combination induced skeletal muscle adaptations, including mitochondrial biogenesis and enhanced anti-oxidant reserves. This synergistic effect of dietary supplementation with low-intensity exercise may be valuable as a complement to treatment, especially in diseases caused by mitochondrial dysfunction.

The Relationship between Exercise and Salivary Oxidative Stress: A Systematic Review.

Salivary content has been reported as a potential biomarker for oxidative stress assessments especially in context of exercise-induced oxidative stress. This systematic review following PRISMA guidelines aimed to evaluate the effects of physical exercise and changes promoted in oxidative stress identified in saliva. Methods: Studies published up to May 2022 were searched in online databases (PubMed, Scopus, Web of Science, The Cochrane Library, LILACS, OpenGrey, and Google Scholar). Risk of bias evaluation were performed using the Quality Assessment Tool for Before-After (Pre-Post) Studies with No Control Group. Results: A total of 473 references were identified and 22 considered eligible. In this case 14 studies reported increase of antioxidant parameters in saliva while eight studies demonstrated increased lipid peroxidation after exercise. Regarding nitrite levels, two studies showed higher levels after exercise. The quality of evidence was very low due to high heterogeneity, inconsistency and indirectness among studies according Grading of Recommendations, Assessment, Development and Evaluation analysis. Conclusion: Increase of oxidative stress and antioxidant activity in saliva appears to be present after exercise, especially at moderate intensity. However, the wide variety of methods leads to divergent data. For precision in salivary assessments, new research with larger sample sizes and better participant matching are recommended.