Dietary thiols in exercise: oxidative stress defence, exercise performance, and adaptation

Phytochemical Analysis and Antioxidant Effects of Prunella vulgaris in Experimental Acute Inflammation

Prunella vulgaris (PV) is one of the most commonly used nutraceuticals as it has been proven to have anti-inflammatory and antioxidant properties. The aim of this study was to evaluate the phytochemical composition of PV and its in vivo antioxidant properties. A phytochemical analysis measuring the total phenolic content (TPC), the identification of phenolic compounds by HPLC-DAD-ESI, and the evaluation of the in vitro antioxidant activity by the DPPH assay of the extract were performed. The antioxidant effects on inflammation induced by turpentine oil were experimentally tested in rats. Seven groups with six animals each were used: a control group, the experimental inflammation treatment group, the experimental inflammation and diclofenac sodium (DS) treatment group, and four groups with their inflammation treated using different dilutions of the extract. Serum redox balance was assessed based on total oxidative status (TOS), nitric oxide (NO), malondialdehyde (MDA), total antioxidant capacity (TAC), total thiols, and an oxidative stress index (OSI) contents. The TPC was 0.28 mg gallic acid equivalents (GAE)/mL extract, while specific representatives were represented by caffeic acid, p-coumaric acid, dihydroxybenzoic acid, gentisic acid, protocatechuic acid, rosmarinic acid, vanillic acid, apigenin-glucuronide, hesperidin, kaempferol-glucuronide. The highest amount (370.45 μg/mL) was reported for hesperidin, which is a phenolic compound belonging to the flavanone subclass. The antioxidant activity of the extracts, determined using the DPPH assay, was 27.52 mmol Trolox/mL extract. The PV treatment reduced the oxidative stress by lowering the TOS, OSI, NO, and MDA and by increasing the TAC and thiols. In acute inflammation, treatment with the PV extract reduced oxidative stress, with lower concentrations being more efficient and having a better effect than DS.

An In Silico In Vitro and In Vivo Study on the Influence of an Eggplant Fruit (Solanum anguivi Lam) Diet on Metabolic Dysfunction in the Sucrose-Induced Diabetic-like Fruit Fly (Drosophila melanogaster)

Introduction: Africa faces immense food and health insecurity challenges, a problem partly attributed to food loss and waste during postharvest handling and distribution. In the context of research to meet the sustainable development goals, this project specifically addressed the postharvest loss of the ripe indigenous eggplant (Solanum anguivi lam) fruit called "Igba Yinrin" by Yoruba in South-West Nigeria, which is usually discarded in farms. The study was carried out on ripe and unripe fruits to better understand their value by comparing their effects in diabetes treatment. Methods: The study sought to assess the effects of a diet including ripe or unripe mature eggplant fruits in the sucrose-induced diabetic-like fruit fly. Bioactive compounds were identified and quantified with HPLC-UV, while the antioxidant vitamin (A, C, E), carotenoid, and mineral (Na, K, Ca, Mg, Fe, P, and Zn) content was analyzed in the fruits. Extracts were used to investigate their in vitro anti-inflammatory properties on cyclooxygenases (COX 1 and 2), 5-lipoxygenase (5-LOX), and anti-diabetes enzymes [α-amylase and α-glucosidase], while extract-supplemented diets (0.25-1% concentration) were fed to the fruit flies for 14 days. Results: Interestingly, the results showed that the ripe fruits had a significantly (p < 0.05) higher total phenol and flavonoid content, as well as a higher content of vitamins, carotenoids, and minerals, than the unripe fruits. The in vivo activities of antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), and glutathione transferase (GST)] and the total thiol level increased, while the blood glucose, reactive oxygen species (ROS), and malondialdehyde (MDA) levels decreased in Drosophila melanogaster (fruit fly). An in silico docking analysis showed strong binding affinity of the above-mentioned enzymes under investigation with the ligands hesperidin, naringin, and myricetin, which are bioactive compounds contained in the examined extracts. Conclusions: There was no significant difference in the biological effects of the ripe and unripe fruit extracts on inflammatory and anti-diabetes enzyme activities, which means that the ripe fruit, usually discarded, could serve as a sustainable alternative source of food nutrients.

Quercetin in Sports and Exercise: A review

This paper systematically reviews the latest evidence regarding Quercetin's (Q) effect following exercise performance, aerobic and anaerobic exercise, muscle-damaging bouts and highlights blood biomarkers associated with muscle damage and recovery. Google Scholar, Web of Science, and MedLine (PubMed) searches were conducted through July-December 2021. Peer-reviewed studies that investigated Q as a single ingredient or in combination with other ingredients at dosages of 500 mg - 3000 mg, ranging from 15 min-to-1 h prior to exercise bout or chronic dose (7 days - 8 weeks) of consumption were included. A total of 34 studies met the inclusion criteria for the review. Key results include significant performance improvements in the following: VO2max (n = 2), time to exhaustion (n = 4 articles), fatigue decrement (n = 1 article), muscle damage (n = 3 articles), strength, torque velocity, and neuromuscular performance (n = 3 articles), redox potential (n = 1 article), repeated sprint performance and oxygen extraction (n = 1). Q also caused a change in systemic biomarkers: decrease in creatine kinase (n = 2), c-reactive protein (n = 4), lactate dehydrogenase (n = 4), inflammatory markers (n = 3), lipid peroxidation (n = 3) in aerobic and anaerobic performance. Varied findings exist regarding the efficacy of Q supplementation on exercise performance and recovery outcomes. The source of Q, training status of subjects, and exercise protocol performed may contribute to the effectiveness of Q as an antioxidant, anti-inflammatory, or ergogenic agent in exercise.

Antibacterial Conductive Collagen-Based Hydrogels for Accelerated Full-Thickness Wound Healing

Antibacterial conductive hydrogels have been extensively utilized in tissue repair and regeneration on account of their unique electrochemical performances and advantages of anti-pathogenic bacterial infection. Here, multi-functional collagen-based hydrogels (CHLY) with adhesivity, conductivity, and antibacterial and antioxidant activities were developed by introducing cysteine-modified ε-poly(l-lysine) (ε-PL-SH) and in situ-polymerized polypyrrole (PPy) nanoparticles to induce full-thickness wound healing. CHLY hydrogels have a low swelling ratio, good compressive strength, and viscoelasticity due to chemical crosslinking, chelation, physical interaction, and nano-reinforcements in the matrix network of hydrogels. CHLY hydrogels possess excellent tissue adhesion ability, low cytotoxicity, enhanced cell migration ability, and good blood coagulation performance without causing hemolysis. Interestingly, the chemical conjugation of ε-PL-SH in the hydrogel matrix gives hydrogels an inherently robust and broad-spectrum antibacterial activity, while the introduction of PPy endows hydrogels with superior free radical scavenging capacity and good electroactivity. Significantly, CHLY hydrogels have advantages in alleviating persistent inflammatory response as well as promoting angiogenesis, epidermis regeneration, and orderly collagen deposition at the wound sites through their multi-functional synergies, thus effectively accelerating full-thickness wound healing and improving wound healing quality. Overall, our developed multi-functional collagen-based hydrogel dressing demonstrates promising application prospects in the field of tissue engineering to induce skin regeneration.

Effect of Lactobacillus plantarum KSFY01 on the exercise capacity of D-galactose-induced oxidative stress-aged mice

Objectives

Aging is a process that involves comprehensive physiological changes throughout the body, and improvements in the exercise capacity of individuals may delay aging and relieve fatigue. Probiotics are subject to ongoing research to investigate their antioxidant properties. The purpose of this study was to investigate the effect of the probiotic Lactobacillus plantarum KSFY01 (L. plantarum KSFY01) on exercise tolerance in mice induced into a state of accelerated physiological aging by oxidative stress.

Methods

A mouse model of accelerated aging was established using D-galactose to induce oxidative stress. The bacteria L. plantarum KSFY01 was isolated from fermented yak yogurt. The effect of L. plantarum KSFY01 on the improvement of exercise capacity in aging-accelerated mice was evaluated by measuring their running time until exhaustion, histopathological sections, related biochemical indicators, and underlying gene expression.

Results

The oral administration of L. plantarum KSFY01 prolonged the running time of mice and reduced their creatine kinase (CK), alanine aminotransferase (ALT), and aspartate aminotransferasem (AST) levels. From this study, we observed that L. plantarum KSFY01 significantly improved the exercise capacity of mice and alleviated liver damage. Treatment with L. plantarum KSFY01 reduced the blood urea nitrogen (BUN), lactic acid (LD) accumulation, and lactate dehydrogenase (LDH) elevations produced by the accelerated aging state, and also reversed the changes in muscle glycogen (MG). Overall, L. plantarum KSFY01 could effectively improve metabolite accumulation, thereby relieving fatigue in exercised mice. The results of the antioxidant indices in vivo showed that L. plantarum KSFY01 intervention increased the activity of antioxidant enzymes, decreased the level of malondialdehyde (MDA), and restored the balance between the oxidative and antioxidant systems in fatigued mice. By investigating the underlying molecular mechanism, our results showed that L. plantarum KSFY01 intervention significantly reversed the decline in the expression levels of nuclear factor-erythroid 2 related factor 2 (Nrf2) signaling pathway-related factors and improved the body's antioxidant capacity. We determined that the underlying molecular mechanism responsible for the antioxidant effect of L. plantarum KSFY01 mainly involves the activation of the Nrf2 pathway. The effect of L. plantarum KSFY01 was dose-dependent, and the expression level of Nrf2 increased with increasing dosage of the probiotic.

Conclusion

This study demonstrated that the probiotic L. plantarum KSFY01 exerts antioxidant effects and improved the athletic ability of mice. These findings are of significance to the development and utilization of probiotic resources.

Antioxidative properties of phenolic compounds and their effect on oxidative stress induced by severe physical exercise

Extensive research has found strongly increased generation of reactive oxygen species, free radicals, and reactive nitrogen species during acute physical exercise that can lead to oxidative stress (OS) and impair muscle function. Polyphenols (PCs), the most abundant antioxidants in the human diet, are of increasing interest to athletes as antioxidants. Current literature suggests that antioxidants supplementation can effectively modulate these processes. This overview summarizes the actual knowledge of chemical and biomechanical properties of PCs and their impact as supplements on acute exercise-induced OS, inflammation control, and exercise performance. Evidence maintains that PC supplements have high potency to positively impact redox homeostasis and improve skeletal muscle's physiological and physical functions. However, many studies have failed to present improvement in physical performance. Eleven of 15 representative experimental studies reported a reduction of severe exercise-induced OS and inflammation markers or enhancement of total antioxidant capacity; four of eight studies found improvement in exercise performance outcomes. Further studies should be continued to address a safe, optimal PC dosage, supplementation timing during a severe training program in different sports disciplines, and effects on performance response and adaptations of skeletal muscle to exercise.

Well-Trained Elders Have Antioxidant Responses and an Equal Magnitude of EIMD as Young Adults

Aim The aim of the study was to investigate acute and chronic effects of a two-week eccentric concentric, dynamometric training concerning the time-course changes of blood antioxidant parameters (total antioxidant capacity, catalase enzyme activity, thiol concentration), and to compare the adaptability of young and older muscle to this type of training. Methods Seventeen moderately trained young and older men participated in this research. Subjects performed six eccentric concentric exercise bouts during the training period and maximal voluntary isometric contraction torque, plasma CK and intensity of muscle soreness were determined before and 24 h after the first exercise. During five testing sessions (baseline, 24 h, 48 h, week 1, week 2) the level of blood antioxidants were measured. Results No significant changes were registered in total antioxidant capacity and catalase enzyme activity for any time points; furthermore, no difference was found between groups during the training period. However, total thiol concentrations measured two weeks after the first exercise bout significantly differed between the young and elderly groups. Plasma CK and the subjective intensity of soreness elevated significantly 24 h following the first training, while maximal voluntary isometric contraction torque decreased at the same time. Conclusions Our results do not support previous findings that chronic, short-term eccentric concentric training programs enhance the antioxidant defense of well-trained older and young men. This type and setting of exercise did not cause a different time course of changes in the markers of exercise-induced muscle damage (EIMD) in the studied population. Subjects may already have adapted to maintain constant levels of antioxidants and isometric torque due to their active lifestyle.

Redox status biomarkers in the fast-twitch extensor digitorum longus resulting from the hypoxic exercise

The fast-twitch muscle may be affected from over-produced reactive oxygen species (ROS) during hypoxia/hypoxic exercise. The study aims to investigate redox status biomarkers in the fast-twitch extensor digitorum longus (EDL) muscle after hypoxic exercise. Male Sprague Dawley rats (eight-week-old) were randomly divided into six groups of the experimental "live high train high (LHTH), live high train low (LHTL) and live low train low (LLTL)" and their respective controls. Before the EDLs' extraction, the animals exercised for a 4-week familiarization period, then they exercised for four-weeks at different altitudes. The LHTH group had higher ratios of lipid hydroperoxides (LHPs) than the experimental groups of LHTL (p=0.004) and LLTL (p=0.002), while having no difference than its control 'LH'. Similarly, a higher percentage of advanced oxidation protein products (AOPP) was determined in the LHTH than the LHTL (p=0.041) and LLTL (p=0.048). Furthermore, oxidation of thiol fractions was the lowest in the LHTH and LH. However, redox biomarkers and thiol fractions illustrated no significant change in the LHTL and LLTL that might ensure redox homeostasis due to higher oxygen consumption. The study shows that not hypoxic exercise/exercise, but hypoxia might itself lead to a redox imbalance in the fast-twitch EDL muscle.

Why Do High-Risk Patients Develop or Not Develop Coronary Artery Disease? Metabolic Insights from the CAPIRE Study

Traditional cardiovascular (CV) risk factors (RFs) and coronary artery disease (CAD) do not always show a direct correlation. We investigated the metabolic differences in a cohort of patients with a high CV risk profile who developed, or did not develop, among those enrolled in the Coronary Atherosclerosis in Outlier Subjects: Protective and Novel Individual Risk Factors Evaluation (CAPIRE) study. We studied 112 subjects with a high CV risk profile, subdividing them according to the presence (CAD/High-RFs) or absence of CAD (No-CAD/High-RFs), assessed by computed tomography angiography. The metabolic differences between the two groups were identified by gas chromatography-mass spectrometry. Characteristic patterns and specific metabolites emerged for each of the two phenotypic groups: high concentrations of pyruvic acid, pipecolic acid, p-cresol, 3-aminoisobutyric acid, isoleucine, glyceric acid, lactic acid, sucrose, phosphoric acid, trimethylamine-N-oxide, 3-hydroxy-3-methylglutaric acid, erythritol, 3-hydroxybutyric acid, glucose, leucine, and glutamic acid; and low concentrations of cholesterol, hypoxanthine, glycerol-3-P, and cysteine in the CAD/High-RFs group vs the No-CAD/High-RFs group. Our results show the existence of different metabolic profiles between patients who develop CAD and those who do not, despite comparable high CV risk profiles. A specific cluster of metabolites, rather than a single marker, appears to be able to identify novel predisposing or protective mechanisms towards CAD beyond classic CVRFs.

Effects of Resistance Training on Oxidative Stress Markers and Muscle Damage in Spinal Cord Injured Rats

Simple Summary

Spinal Cord Injury is a devastating condition that compromises the individual’s health, quality of life and functional independence. Rats submitted to Spinal Cord Injury were evaluated after four weeks of resistance training. Analyses of levels of muscle damage and oxidative stress surgery were performed. Resistance training demonstrated increase antioxidative activity while decreased oxidative damage in injured rats, in addition to having presented changes in the levels of muscle damage in that same group. The results highlight that resistance training promoted a decrease in oxidative stress and a significant response in muscle damage markers.

Abstract

Background: Spinal cord injury (SCI) is a condition that affects the central nervous system, is characterized by motor and sensory impairments, and impacts individuals’ lives. The objective of this study was to evaluate the effects of resistance training on oxidative stress and muscle damage in spinal cord injured rats. Methodology: Forty Wistar rats were selected and divided equally into five groups: Healthy Control (CON), Sham (SHAM) SCI Untrained group (SCI-U), SCI Trained group (SCI- T), SCI Active Trained group (SCI- AT). Animals in the trained groups were submitted to an incomplete SCI at T9. Thereafter, they performed a protocol of resistance training for four weeks. Results: Significant differences in muscle damage markers and oxidative stress in the trained groups, mainly in SCI- AT, were found. On the other hand, SCI- U group presented higher levels of oxidative stress and biomarkers of LDH and AST. Conclusion: The results highlight that resistance training promoted a decrease in oxidative stress and a significative response in muscle damage markers.

Cardiorespiratory and metabolic fitness indicators in novice volleyball trainees: effect of 1-week antioxidant supplementation with N-acetyl-cysteine/zinc/vitamin C

OBJECTIVES

This study aimed to determine the effect of 7-day dietary supplementation of N-acetylcysteine (NAC)/zinc/vitamin C on the time-to-exhaustion (TTE), the cardiorespiratory fitness (CRF) index, and metabolic indicators.

METHODS

This study enrolled volleyball student trainees (n = 18 men) who took NAC/zinc/vitamin C (750 mg/5 mg/100 mg) for 7 days at Jouf University, Saudi Arabia. The CRF index and TTE were determined. Serum concentrations of metabolic regulators (insulin, betatrophin, and hepatocyte growth factor), biomarkers of cellular damage/hypoxia, and indicators of lipid and glycemic control were measured.

RESULTS

Supplementation improved the TTE and CRF index, and lowered cytochrome c, C-reactive protein, hypoxia-inducible factor-1α (HIF-1α), total cholesterol, insulin, and glycated hemoglobin values. Before and after supplementation, the CRF index was negatively correlated with body mass index and positively correlated with the TTE. Before supplementation, the CRF index was positively correlated with betatrophin concentrations, and hepatocyte growth factor concentrations were positively correlated with betatrophin concentrations and negatively correlated with the homeostasis model assessment of insulin resistance index. After supplementation, the CRF index was negatively correlated with HIF-1α concentrations and metabolites. Additionally, the TTE was negatively correlated with HIF-1α, cytochrome c, and triacylglycerol concentrations.

CONCLUSION

Supplementation of NAC/zinc/vitamin C improves metabolic and CRF performance.

Pulmonary arterial hypertension induces the release of circulating extracellular vesicles with oxidative content and alters redox and mitochondrial homeostasis in the brains of rats

Pulmonary arterial hypertension (PAH) is characterized by increased resistance of the pulmonary vasculature and afterload imposed on the right ventricle (RV). Two major contributors to the worsening of this disease are oxidative stress and mitochondrial impairment. This study aimed to explore the effects of monocrotaline (MCT)-induced PAH on redox and mitochondrial homeostasis in the RV and brain and how circulating extracellular vesicle (EV) signaling is related to these phenomena. Wistar rats were divided into control and MCT groups (60 mg/kg, intraperitoneal), and EVs were isolated from blood on the day of euthanasia (21 days after MCT injections). There was an oxidative imbalance in the RV, brain, and EVs of MCT rats. PAH impaired mitochondrial function in the RV, as seen by a decrease in the activities of mitochondrial complex II and citrate synthase and manganese superoxide dismutase (MnSOD) protein expression, but this function was preserved in the brain. The key regulators of mitochondrial biogenesis, namely, proliferator-activated receptor gamma coactivator 1-alpha and sirtuin 1, were poorly expressed in the EVs of MCT rats, and this result was positively correlated with MnSOD expression in the RV and negatively correlated with MnSOD expression in the brain. Based on these findings, we can conclude that the RV is severely impacted by the development of PAH, but this pathological injury may signal the release of circulating EVs that communicate with different organs, such as the brain, helping to prevent further damage through the upregulation of proteins involved in redox and mitochondrial function.

Variations of Thiol-Disulfide Homeostasis Parameters after Treatment with H1-Antihistamines in Patients with Chronic Spontaneous Urticaria

Background. The pathogenesis of chronic spontaneous urticaria involves metabolic, immunological, and psychological factors. The thiol–disulfide exchange reactions could be a mechanism to counteract oxidative stress in patients with chronic spontaneous urticaria. Objective: The assessment of thiol–disulfide homeostasis parameters (TDHPs) according to disease severity and the influence of H1-antihistamine therapy in patients with chronic spontaneous urticaria. Material and method. We have included 30 patients with chronic spontaneous urticaria in the study and we have determined the levels of native thiol, total thiol, disulfides as well as the disulfide/native thiol ratio, disulfide/total thiol ratio and the native thiol/total thiol ratio, before and after therapy with H1-antihistamines. Results. The results of the study showed altered levels of TDHPs and their normalization after treatment with H1-antihistamines in patients with chronic spontaneous urticaria. We determined a statistically significant increase in the serum levels of total thiol, native thiol, and native thiol/total thiol ratio and a significant reduction in the levels of disulfides, disulfide/native thiol ratio and disulfide/total thiol ratio after treatment with H1-antihistamines. The normalization of the serum levels of TDHPs has been associated with the relief of symptoms and reduction or resolution of pruritus and urticarial plaques. Conclusion. These results suggest the involvement of thiol–disulfide homeostasis in the defense against the harmful effects of reactive oxygen species in patients with chronic spontaneous urticaria and the potential role of TDHPs in monitoring H1-antihistamine therapy. To the best of our knowledge, this is the first study investigating TDHPs in patients with chronic spontaneous urticaria before and after treatment.

Mechanisms of Physical Fatigue and its Applications in Nutritional Interventions

Physical fatigue during exercise can be defined as an impairment of physical performance. Multiple factors have been found contributing to physical fatigue, including neurotransmitter-mediated defense action, insufficient energy supply, and induction of oxidative stress. These mechanistic findings provide a sound theoretical rationale for nutritional intervention since most of these factors can be modulated by nutrient supplementation. In this review, we summarize the current evidence regarding the functional role of nutrients supplementation in managing physical performance and propose the issues that need to be addressed for better utilization of nutritional supplementation approach to improve physical performance.

Effects of antioxidant supplementation on oxidative stress balance in young footballers- a randomized double-blind trial

BACKGROUND

Intensive physical exercise that competitive sports athletes participate in can negatively affect their pro-oxidative-antioxidant balance. Compounds with high antioxidant potential, such as those present in chokeberry (Aronia melanocarpa), can prevent these adverse changes. We here investigated the effect of antioxidant supplementation on oxidative stress balance in young footballers.

METHODS

The study was designed as a double-blind randomized trial. Diet of a group of young football players (male; n = 20; mean age, 15.8 years-old) was supplemented with 200 ml of chokeberry juice per day, for 7 weeks. The players were randomly assigned to the experimental (supplemented, FP-S; n = 12) and control (placebo, FB-C; n = 8) groups. Before and after the supplementation period, the participants performed a beep test. Venous blood was sampled for serum analysis before, immediately after, 3 h, and 24 h after the beep test. Serum levels of thiobarbituric acid reactive products, 8-hydroxy-2'-deoxyguanosine, total antioxidant capacity, iron, hepcidin, ferritin, myoglobin, and albumin, and morphological blood parameters (red blood cells, (RBC), haemoglobin (HGB), haematocrit (HCT) mean corpuscular volume (MCV) mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), and lactic acid) were determined.

RESULTS

Chokeberry juice supplementation did not significantly affect the outcome of the beep test. The supplementation did not significantly affect any of the morphological, biochemical, or performance parameters analysed.

CONCLUSIONS

Chokeberry juice supplementation did not affect the measured parameters in the studied population, which may indicate insufficient antioxidant capacity of the juice.

Redox and autonomic responses to acute exercise-post recovery following Opuntia ficus-indica juice intake in physically active women

BACKGROUND

The aim of this study was to investigate if the supplementation with Opuntia ficus-indica (OFI) juice may affect plasma redox balance and heart rate variability (HRV) parameters following a maximal effort test, in young physically active women.

METHODS

A randomized, double blind, placebo controlled and crossover study comprising eight women (23.25 ± 2.95 years, 54.13 ± 9.05 kg, 157.75 ± 0.66 cm and BMI of 21.69 ± 0.66 kg/m2) was carried out. A juice containing OFI diluted in water and a Placebo solution were supplied (170 ml; OFI = 50 ml of OFI juice + 120 ml of water; Placebo = 170 ml beverage without Vitamin C and indicaxanthin). Participants consumed the OFI juice or Placebo beverage every day for 3 days, before performing a maximal cycle ergometer test, and for 2 consecutive days after the test. Plasma hydroperoxides and total antioxidant capacity (PAT), Skin Carotenoid Score (SCS) and HRV variables (LF, HF, LF/HF and rMSSD) were recorded at different time points.

RESULTS

The OFI group showed significantly lower levels of hydroperoxides compared to the Placebo group in pre-test, post-test and 48-h post-test. PAT values of the OFI group significantly increased compared to those of the Placebo group in pre-test and 48-h post-test. SCS did not differ between groups. LF was significantly lower in the OFI group 24-h after the end of the test, whereas rMSSD was significantly higher in the OFI group 48-h post-test.

CONCLUSION

OFI supplementation decreased the oxidative stress induced by intense exercise and improved autonomic balance in physically active women.

Injectable adaptive self-healing hyaluronic acid/poly (γ-glutamic acid) hydrogel for cutaneous wound healing

The most significant challenge in designing wound dressings is to mimic the tissue microenvironment because of the pro-regenerative structural and functional properties of skin. Herein, we developed a type of bionic extracellular matrix (ECM) hydrogels based on thiol-modified poly (γ-glutamic acid) (γ-PGA-SH) and oxidized hyaluronic acid (HA-CHO). The rapid and reversible thiol-aldehyde addition reaction of thiols in γ-PGA-SH and aldehyde groups in HA-CHO provided hydrogels with a dynamic covalent network and endowed them with properties of adaptability and self-healing capability, which are conducive for initial wound coverage and for prolonging the lifespan of the dressing. Interestingly, these hydrogels also showed typical viscoelastic characteristics similar to those of natural ECM, degradation property in vitro and in vivo, and free radical scavenging capability. In addition, the gelation time, rheological behavior, mechanical property, porous structure, and degradation process of the hydrogels could be tuned by adjusting polymer content. Furthermore, the ECM-inspired hydrogels significantly enhanced the wound healing process in vivo in a full-thickness skin defect model compared to those by commercial dressing (Tegaderm™) by facilitating angiogenesis and promoting collagen deposition. The successful application of the multifunctional hydrogel as an antioxidant wound dressing for wound treatment significantly exhibited its great application potential for biomedical areas. STATEMENT OF SIGNIFICANCE: The application of tissue engineering techniques to repair full-thickness skin wounds remains a great challenge in clinical trials. Among the recent approaches used for wound healing, in situ forming injectable hydrogels have gained much attention, and few of them have shown satisfactory overall performance, such as integration into the wound bed, biodegradability, immunocompatibility, vascularization, and recapitulation of the structure and function of skin. In the present study, we designed a simple and convenient in situ forming injectable adaptable self-healing hydrogels with biodegradability and antioxidative properties, which could substantially improve wound healing quality at an affordable cost. The hydrogel-based wound dressing is expected to solve the abovementioned problems and help in promoting cutaneous wound healing.

Effect of taurine associated gold nanoparticles on oxidative stress in muscle of mice exposed to overuse model

Muscle overuse and its consequent muscle damage has no cure. Therefore, the present study aimed to investigate the regulatory role of tau-AuNPs on muscle recovery of muscle overuse model. The animals (Male Swiss mice) were randomly divided into four groups: Control (Ctr; n=6); tau-AuNPs (n=6); overuse (n=6); and overuse plus tau-AuNPs (n=6). Exercise sessions were performed for 21 consecutive days, and one exercise model was applied daily in the following sequence: low intensity, moderate intensity, and high intensity. The mice were then sacrificed. The quadriceps muscles were surgically removed for subsequent biochemical analysis (oxidative stress parameters, DNA damage markers and muscle differentiation protein). The overuse group significantly increased the oxidative stress parameters and DNA damage markers, whereas tau-AuNPs significantly decreased the oxidative stress parameters in the overuse animal model. However, there were no significant differences observed between overuse group and overuse plus tau-AuNPs administrated group in relation to DNA damage markers including DNA damage frequency and index levels when compared to control and tau-AuNPs groups. Muscle differentiation protein Myf-5 was increased in the overuse plus tau-AuNPs administration group when compared to control group. In conclusion, tau-AuNPs had significant effect on reducing oxidative stress parameters and increasing myogenic regulatory protein Myf-5 in the overuse group. However, it did not have significant effect on reducing DNA damage.

Simultaneous Determination of Chiral Thiol Compounds and Monitoring of Dynamic Changes in Human Urine after Drinking Chinese Korean Ethnic Rice Wine

Chinese Korean ethnic rice wine, a traditional fermented wine made from rice or corn, has antioxidant and antihypertensive activities. Although the determination of amino acids and other nutrients in rice wine has been reported, the existence of chiral thiol compounds has not been published in the literature. Therefore, we established a highly sensitive and selective ultrahigh-performance liquid chromatography-high-resolution mass spectrometry method for simultaneous determination and chiral separation of dl-Cys-GSH, dl-Cys-Cys, and dl-Cys-Hcy based on (R)-(5-(3-isothiocyanatopyrrolidin-1-yl)-5-oxopentyl) triphenylphosphonium derivatization. Three thiol diastereomers were completely separated on a YMC Triart C18 (2.0 × 150 mm, 1.9 μm) column with a resolution value (Rs) ≥ 1.52. The correlation coefficients were ≥0.9996, limit of detection was 2.40-7.20 fmol, and mean recoveries were 83.33-98.59%. Furthermore, fitted curves for dynamic changes in three kinds of chiral thiols in 10 human urine samples after drinking rice wine were drawn. Meanwhile, the metabolic changes in d/l-thiol compounds in human urine were investigated.

Protein network analyses of pulmonary endothelial cells in chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is a vascular disease characterized by the presence of organized thromboembolic material in pulmonary arteries leading to increased vascular resistance, heart failure and death. Dysfunction of endothelial cells is involved in CTEPH. The present study describes for the first time the molecular processes underlying endothelial dysfunction in the development of the CTEPH. The advanced analytical approach and the protein network analyses of patient derived CTEPH endothelial cells allowed the quantitation of 3258 proteins. The 673 differentially regulated proteins were associated with functional and disease protein network modules. The protein network analyses resulted in the characterization of dysregulated pathways associated with endothelial dysfunction, such as mitochondrial dysfunction, oxidative phosphorylation, sirtuin signaling, inflammatory response, oxidative stress and fatty acid metabolism related pathways. In addition, the quantification of advanced oxidation protein products, total protein carbonyl content, and intracellular reactive oxygen species resulted increased attesting the dysregulation of oxidative stress response. In conclusion this is the first quantitative study to highlight the involvement of endothelial dysfunction in CTEPH using patient samples and by network medicine approach.

How N-Acetylcysteine Supplementation Affects Redox Regulation, Especially at Mitohormesis and Sarcohormesis Level: Current Perspective

Exercise frequently alters the metabolic processes of oxidative metabolism in athletes, including exposure to extreme reactive oxygen species impairing exercise performance. Therefore, both researchers and athletes have been consistently investigating the possible strategies to improve metabolic adaptations to exercise-induced oxidative stress. N-acetylcysteine (NAC) has been applied as a therapeutic agent in treating many diseases in humans due to its precursory role in the production of hepatic glutathione, a natural antioxidant. Several studies have investigated NAC’s possible therapeutic role in oxidative metabolism and adaptive response to exercise in the athletic population. However, still conflicting questions regarding NAC supplementation need to be clarified. This narrative review aims to re-evaluate the metabolic effects of NAC on exercise-induced oxidative stress and adaptive response developed by athletes against the exercise, especially mitohormetic and sarcohormetic response.

Grape polyphenols supplementation for exercise-induced oxidative stress

Exercise induces free radicals’ overproduction and therefore, an enhancement of oxidative stress, defined as an imbalance between the production of reactive species and the intrinsic antioxidant defense. Redox activity of reactive species plays an important and a positive role on exercise adaptation, but these species at very high concentrations have detrimental effects. As a result, the use of antioxidant supplements for reducing oxidative stress can be an effective health strategy to maintain an optimal antioxidant status. In this sense, grapes are an important source of natural antioxidants due to their high content in polyphenols. They have shown antioxidant potential benefits for the reduction of intense exercise effect in athletes of different sport disciplines. Consequently, it is plausible to hypothesize that a strategic supplementation with grape based products may be a good approach to mitigate the exercise induced oxidative stress. The goal of this review is to present the state of the art of supplementation effects with grape beverages and grape extracts on the oxidative stress markers in athletes. The data of polyphenolic dosages, participant characteristics and exercise protocols are reported.

Dietary Thiols: A Potential Supporting Strategy against Oxidative Stress in Heart Failure and Muscular Damage during Sports Activity

Moderate exercise combined with proper nutrition are considered protective factors against cardiovascular disease and musculoskeletal disorders. However, physical activity is known not only to have positive effects. In fact, the achievement of a good performance requires a very high oxygen consumption, which leads to the formation of oxygen free radicals, responsible for premature cell aging and diseases such as heart failure and muscle injury. In this scenario, a primary role is played by antioxidants, in particular by natural antioxidants that can be taken through the diet. Natural antioxidants are molecules capable of counteracting oxygen free radicals without causing cellular cytotoxicity. In recent years, therefore, research has conducted numerous studies on the identification of natural micronutrients, in order to prevent or mitigate oxidative stress induced by physical activity by helping to support conventional drug therapies against heart failure and muscle damage. The aim of this review is to have an overview of how controlled physical activity and a diet rich in antioxidants can represent a “natural cure” to prevent imbalances caused by free oxygen radicals in diseases such as heart failure and muscle damage. In particular, we will focus on sulfur-containing compounds that have the ability to protect the body from oxidative stress. We will mainly focus on six natural antioxidants: glutathione, taurine, lipoic acid, sulforaphane, garlic and methylsulfonylmethane.

l-Cysteine and Vitamin D Co-Supplementation Alleviates Markers of Musculoskeletal Disorders in Vitamin D-Deficient High-Fat Diet-Fed Mice

Vitamin D (VD) deficiency is associated with musculoskeletal disorders. This study examines whether co-supplementation of l-cysteine (LC) and VD is better than monotherapy with LC or VD at alleviating musculoskeletal dyshomeostasis in the skeletal muscle of VD-deficient high-fat diet (HFD-VD-) fed mice. Mice were fed a healthy diet or an HFD; for VD-deficient animals, the mice were maintained on a HFD-VD-diet (16 weeks); after the first 8 weeks, the HFD-VD-diet-fed mice were supplemented for another 8 weeks with LC, VD-alone, or the same doses of LC + VD by oral gavage. Saline and olive oil served as controls. Myotubes were exposed with high-glucose, palmitate, Monocyte Chemoattractant Protein 1 (MCP-1), and Tumor Necrosis Factor (TNF), to mimic the in vivo microenvironment. In vitro deficiencies of glutathione and hydrogen sulfide were induced by knockdown of GCLC and CSE genes. Relative gene expression of biomarkers (myogenic: MyoD, Mef2c, Csrp3; muscle dystrophy: Atrogin1, Murf1, and Myostatin; bone modeling and remodeling: RANK, RANKL, OPG) were analyzed using qRT-PCR. Co-supplementatoin with LC + VD showed beneficial effects on gene expression of myogenic markers and OPG but reduced markers of dystrophy, RANK/RANKL in comparison to LC or VD alone-supplementation. In vitro myotubes treated with glutathione (GSH) precursors also showed a positive effect on OPG and the myogenesis genes, and inhibited RANK/RANKL and muscle-dystrophy markers. This study reveals that the co-supplementation of LC with VD significantly alleviates the markers of musculoskeletal disorders in the skeletal muscle better than monotherapy with LC or VD in HFD-VD-fed mice.

Effects of Resistance Training and Bowdichia virgilioides Hydroethanolic Extract on Oxidative Stress Markers in Rats Submitted to Peripheral Nerve Injury

The objective of this study was to analyze the effects of the combination of resistance training (RT) and the hydroethanolic extract (EHE) of Bowdichia virgilioides as markers of oxidative stress (OS) in rats with peripheral nerve injury (PNI). Rats were allocated into six groups (n = 10): animals without interventions (C), animals with an exposed nerve but without injury, injured animals, trained and injured animals, injured animals that received EHE, and animals that received a combination of RT and EHE. RT comprised the climbing of stairs. EHE was orally administered (200 mg/kg) for 21 days after PNI induction. RT reduced the amount of lipoperoxidation in plasma (14.11%). EHE reduced lipoperoxidation in the plasma (20.72%) and the brain (41.36). RT associated with the extract simultaneously reduced lipoperoxidation in the plasma (34.23%), muscle (25.13%), and brain (43.98%). There was an increase in total sulhydrilyl levels (a) in the brain (33.33%) via RT; (b) in the brain (44.44%) and muscle (44.51%) using EHE; and (c) in the plasma (54.02%), brain (54.25%), and muscle using the combination of RT + EHE. These results suggest that RT associated with oral EHE results in a decrease in OS.

Change in Oxidative Stress Biomarkers During 30 Days in Saturation Dive: A Pilot Study

Saturation diving allows divers to reduce the risk of decompression sickness while working at depth for prolonged periods but may increase reactive oxygen species (ROS) production. Such modifications can affect endothelial function by exacerbating oxidative stress. This study investigated the effects of saturation diving on oxidative stress damage. Redox status was evaluated through: ROS production; total antioxidant capacity (TAC); nitric oxide metabolites (NOx); nitrotyrosine (3-NT); and lipid peroxidation (8-iso-PGF2α) assessment. Creatinine and neopterin were analyzed as markers of renal function and damage. Measurements were performed on saliva and urine samples obtained at four time points: pre; deep; post; and 24 h post. Four divers were included in the study. After the saturation dive (post), significant (p < 0.05) increases in ROS (0.12 ± 0.03 vs. 0.36 ± 0.06 µmol.min^-1), TAC (1.88 ± 0.03 vs. 2.01 ± 0.08 mM), NOx (207.0 ± 103.3 vs. 441.8 ± 97.3 µM), 3-NT (43.32 ± 18.03 vs. 18.64 ± 7.45 nM·L^-1), and 8-iso-PGF2α (249.7 ± 45.1 vs. 371.9 ± 54.9 pg·mg^-1 creatinine) were detected. Markers of renal damage were increased as well after the end of the saturation dive (creatinine 0.54 ± 0.22 vs. 2.72 ± 1.12 g-L^-1; neopterin 73.3 ± 27.9 vs. 174.3 ± 20.53 μmol·mol^-1 creatinine). These results could ameliorate commercial or military diving protocols or improve the understanding of symptoms caused by oxygen level elevation.

"Live High Train Low" Hypoxic Training Enhances Exercise Performance with Efficient Redox Homeostasis in Rats' Soleus Muscle

Çolak, Rıdvan, Eda Ağaşcıoğlu, and Ufuk Çakatay. "Live high train low" hypoxic training enhances exercise performance with efficient redox homeostasis in rats' soleus muscle. High Alt Med Biol. 22:77-86, 2021. Background: Different types of hypoxic training have been performed to improve exercise performance. Although both "live high train high" and "live high train low" techniques are commonly performed, it is still obscure as to which one is more beneficial. Materials and Methods: Eight-week-old male Sprague-Dawley rats were randomly divided into aforementioned experimental groups. After a familiarization exercise (4-week, ∼15-30 minutes/day) at normoxia, all rats exercised (4-week, ∼35 minutes/day) at hypoxia with their pre-evaluated maximal aerobic velocity test. The soleus was extracted after the test following 2 days of resting. Results: The live high trained low group displayed better performance than the live high trained high (p = 0.031) and the live low trained low (p = 0.017) groups. Redox status biomarkers were higher in the live high trained high group except for thiols, which were illustrated with no difference among the groups. Further, contrary to total and protein thiols (r = 0.57, p = 0.037; r = 0.55, p = 0.042 respectively), other redox status biomarkers were observed to be negatively correlated to exercise performance. Conclusions: The live high trained low group could consume more oxygen during exercise, which might lead to having a better chance to ensure cellular redox homeostasis. Therefore, this group could ensure an optimum exercise performance and anabolic metabolism.

Assessment of Dietary Intake and Nutritional Status in CrossFit-Trained Individuals: A Descriptive Study

CrossFit is a discipline with high training and nutritional requirements. To date, there is only scarce data evaluating nutrition among CrossFit training and they mostly focus on selected nutritional interventions. Therefore, the purpose of this descriptive study was the assessment of dietary intake and nutritional status in a selected group of CrossFit-trained participants. The study consisted of 62 CrossFit athletes (31 men and 31 women, aged 31.0 ± 5.2 and 30.0 ± 4.3 years, respectively). Body composition was analyzed by electrical bioimpedance. Dietary intake was assessed using a standardized 3-day food record. Body fat percentage for females and males was 20.3 ± 4.3% and 13.7 ± 3.3% respectively. The energy intake in the diet was lower (~1700 kcal in women and ~2300 kcal in men) than the recommended demand. Moreover, low consumption of carbohydrates was stated, as well as an inadequate intake of folate, vitamin E (in women), and minerals, such as Fe and Ca (in women). The energy, carbohydrate, iron, and calcium intake in the CrossFit participants' diet was too low in comparison to recommendations. It seems justified to educate athletes and coaches about nutritional habits, and individual energy and nutrients requirements.

Total Dietary Antioxidant Intake Including Polyphenol Content: Is it Capable to Fight against Increased Oxidants within the Body of Ultra-Endurance Athletes?

The role of dietary antioxidants on exhaustive exercise-induced oxidative stress has been well investigated. However, the contribution of total dietary antioxidant capacity on exogenous antioxidant defense and exercise performance has commonly been disregarded. The aims of the present investigation were to examine (i) the effects of dietary total antioxidant intake on body antioxidant mechanisms, and (ii) an exhaustive exercise-induced oxidative damage in ultra-endurance athletes. The study included 24 ultra-marathon runners and long-distance triathletes (12 male and 12 female) who underwent an acute exhaustive exercise test (a cycle ergometer (45 min at 65% VO₂max) immediately followed by a treadmill test (75% VO₂max to exhaustion). Oxidative stress-related biomarkers (8-isoprostaglandin F2alpha (8-iso PGF2a), total oxidant status (TOS, total antioxidant status (TAS)) in plasma were collected before and after exercise. Oxidative stress index was calculated to assess the aspect of redox balance. Blood lactate concentrations and heart rate were measured at the 3rd and 6th min after exercise. Dietary antioxidant intake was calculated using the ferric reducing ability of plasma (FRAP) assay. Dietary total antioxidant intake of the subjects was negatively correlated with pre-exercise TOS concentrations (rs = -0.641 in male, and rs = -0.741 in females) and post- vs. pre- (∆) 8-iso PGF2a levels (rs = -0.702 in male; p = 0.016, and rs = -0.682 in females; p = 0.024), and positively correlated with ∆ TAS concentrations (rs = 0.893 in males; p = 0.001, and rs = 0.769 in females; p = 0.002) and post- exercise lactate concentrations (rs = 0.795 for males; p = 0.006, and rs = 0.642 for females; p = 0.024). A positive meaningful (p = 0.013) interaction was observed between time at exhaustion and dietary antioxidant intake (rs = 0.692) in males, but not in females. In conclusion, the determination of total dietary antioxidant intake in ultra-endurance athletes may be crucial for gaining a better perspective on body antioxidant defense against exhaustive exercise-induced oxidative stress. However, the effects of dietary antioxidant on exercise performance and recovery rate needs further investigation.

N-Acetylcysteine Reduces Skeletal Muscles Oxidative Stress and Improves Grip Strength in Dysferlin-Deficient Bla/J Mice

Dysferlinopathy is an autosomal recessive muscular dystrophy resulting from mutations in the dysferlin gene. Absence of dysferlin in the sarcolemma and progressive muscle wasting are hallmarks of this disease. Signs of oxidative stress have been observed in skeletal muscles of dysferlinopathy patients, as well as in dysferlin-deficient mice. However, the contribution of the redox imbalance to this pathology and the efficacy of antioxidant therapy remain unclear. Here, we evaluated the effect of 10 weeks diet supplementation with the antioxidant agent N-acetylcysteine (NAC, 1%) on measurements of oxidative damage, antioxidant enzymes, grip strength and body mass in 6 months-old dysferlin-deficient Bla/J mice and wild-type (WT) C57 BL/6 mice. We found that quadriceps and gastrocnemius muscles of Bla/J mice exhibit high levels of lipid peroxidation, protein carbonyls and superoxide dismutase and catalase activities, which were significantly reduced by NAC supplementation. By using the Kondziela’s inverted screen test, we further demonstrated that NAC improved grip strength in dysferlin deficient animals, as compared with non-treated Bla/J mice, without affecting body mass. Together, these results indicate that this antioxidant agent improves skeletal muscle oxidative balance, as well as muscle strength and/or resistance to fatigue in dysferlin-deficient animals.

Physical exercise: An inducer of positive oxidative stress in skeletal muscle aging

Oxidative stress is the core of most pathological situations, and its attribution toward disease conversion is not yet well established. The adaptive capacity of a cell can overcome ROS-induced pathology. However, when a cell fails to extend its maximum adaptive capacity against oxidative stress, it could lead a cell to misbehave or defunct from its normal functions. Any type of physical activity can increase the cells' maximum adaptive capacity, but aging can limit this. However, whether aging is the initiating point of reducing cells' adaptive capacity against oxidative stress or oxidative stress can induce the aging process is a mystery, and it could be the key to solving several uncured diseases. Paradoxically, minimum ROS is needed for cellular homeostasis. Nevertheless, finding factors that can limit or nullify the production of ROS for cellular homeostasis is a million-dollar question. Regular physical exercise is considered to be one of the factors that can limit the production of ROS and increase the ROS-induced benefits in the cells through inducing minimum oxidative stress and increasing maximum adapting capacity against oxidative stress-induced damages. The type and intensity of exercise that can produce such positive effects in the cells remain unclear. Therefore, this review discusses how physical exercise can help to produce minimal positive oxidative stress in preventing skeletal muscle aging.

Relationship between postpartum uterine involution and biomarkers of inflammation and oxidative stress in clinically healthy mares (Equus caballus)

To test the hypothesis that delayed/impaired uterine involution could be associated with oxinflammation, we studied the progression of the uterine involution in association with some biomarkers of inflammation and oxidative stress in clinically healthy mares (N = 26) during early postpartum. The examination of the reproductive tract was performed on Days 7 and 21 after foaling. Uterine involution was assessed considering: a) the increase of the gravid uterine horn diameter (GUHD) compared with diameter recorded before pregnancy during the previous breeding season; b) the level of endometrial edema (EE); c) the degree of accumulation of intrauterine fluid (IUFA); d) the status of the cervix (CS). Inflammation and oxidative stress were studied by measuring serum amyloid A (SAA), cortisol, DHEA, AOPP, protein carbonyl groups, malondialdheyde (MDA) and thiols in plasma on Days 7 and 21. By Day 21 after parturition, a significant improvement (P < 0.01) was observed for GUHD and EE; while IUFA increased in six animals. Plasma SAA and DHEA concentrations were higher when the clinical parameters indicated a lower degree of uterine involution. On Day 7, the cortisol/DHEA ratio was lower in animals with higher degree of EE. Plasma AOPP and MDA concentrations were significantly lower (P < 0.05) in animals with the lower GUHD. On Day 21, plasma MDA concentrations were significantly lower (P < 0.05) in animals with the lower IUFA. Our data suggest that a mild condition of inflammation and oxidative stress occur in mares with delayed/impaired uterine involution.

Acute Effects of Triathlon Race on Oxidative Stress Biomarkers

The response to strenuous exercise was investigated by reactive oxygen species (ROS) production, oxidative damage, thiol redox status, and inflammation assessments in 32 enrolled triathlon athletes (41.9 ± 7.9 yrs) during Ironman® (IR), or half Ironman® (HIR) competition. In biological samples, inflammatory cytokines, aminothiols (glutathione (GSH), homocysteine (Hcy), cysteine (Cys), and cysteinylglycine (CysGly)), creatinine and neopterin, oxidative stress (OxS) biomarkers (protein carbonyl (PC), thiobarbituric acid-reactive substances (TBARS)), and ROS were assessed. Thirteen HIR and fourteen IR athletes finished the race. Postrace, ROS (HIR +20%; IR +28%; p < 0.0001), TBARS (HIR +57%; IR +101%), PC (HIR +101%; IR +130%) and urinary neopterin (HIR +19%, IR +27%) significantly (range p < 0.05-0.0001) increased. Moreover, HIR showed an increase in total Cys +28%, while IR showed total aminothiols, Cys, Hcy, CysGly, and GSH increase by +48, +30, +58, and +158%, respectively (range p < 0.05-0.0001). ROS production was significantly correlated with TBARS and PC (R 2 = 0.38 and R 2 = 0.40; p < 0.0001) and aminothiols levels (range R 2 = 0.17-0.47; range p < 0.01-0.0001). In particular, ROS was directly correlated with the athletes' age (R 2 = 0.19; p < 0.05), with ultraendurance years of training (R 2 = 0.18; p < 0.05) and the days/week training activity (R 2 = 0.16; p < 0.05). Finally, the days/week training activity (hours/in the last 2 weeks) was found inversely correlated with the IL-6 postrace (R 2 = -0.21; p < 0.01). A strenuous performance, the Ironman® distance triathlon competition, alters the oxidant/antioxidant balance through a great OxS response that is directly correlated to the inflammatory parameters; furthermore, the obtained data suggest that an appropriate training time has to be selected in order to achieve the lowest ROS production and IL-6 concentration at the same time.

The effects of isoflavone supplementation plus combined exercise on salivary markers of oxidative stress in postmenopausal women

This study tested the effect of isoflavone supplementation in addition to combined exercise training in salivary oxidative stress markers in non-obese postmenopausal women. Thirty-two postmenopausal women without hormone therapy were randomly assigned to exercise + placebo (n = 15) or exercise + isoflavone supplementation (n = 17) groups. They performed 30 sessions of combined exercises (aerobic plus resistance) over ten weeks and consumed 100 mg of isoflavone supplementation or placebo. Saliva samples were collected after an overnight fast. Superoxide dismutase, total antioxidant capacity, thiobarbituric acid reactive substances, catalase, total protein and nitrite were determined before and after ten weeks of the intervention. The ANOVA two-way analysis of variance was applied with α of 5%. Both groups increase (p<0.05) superoxide dismutase activity and decrease catalase levels. There was interaction (time × group) in both nitrite and thiobarbituric acid reactive substances results, with increase (p<0.05) in placebo group and decrease (p<0.05) in isoflavone group. No difference was found for total antioxidant capacity or total protein. The combination of isoflavone supplementation and exercise training can promote an antioxidant effect through reduction of lipid peroxidation and concentrations of salivary nitrite.

Oxidative stress assessment in breath-hold diving

PURPOSE

Breath-hold diving results in significant changes in blood gases' levels. Challenging variations in oxygen partial pressures may induce reactive oxygen species (ROS) production that exacerbate oxidative stress and, consequently, affect endothelial function. The aim of this study was to investigate the effects of breath-hold diving on oxidative stress damage, assessing ROS production. Nitric oxide metabolites, inducible nitric oxide synthase (iNOS), aminothiols, and renal function were evaluated too as markers of redox status and renal damage.

METHODS

ROS production was assessed with electron paramagnetic resonance. Oxidative status values were measured at pre- and post-40 m dive in a deep swimming pool (Y-40) from six divers (mean age 46.6 ± 9.3 years; height 176 ± 4 cm; BMI 25 ± 2.9 kg/m²).

RESULTS

Significant (p < 0.05) increases at post-dive of ROS production rate (0.158 ± 0.003 vs 0.195 ± 0.006 μmol min^-1), lipid peroxidation (8-isoprostane: 375.67 ± 195.62 vs 420.49 ± 232.31 pg mg^-1 creatinine), nitrate (27.91 ± 19.71 vs 30.80 ± 20.44 μM), iNOS (31.30 ± 4.52 vs 35.68 ± 6.72 IU mL^-1) and neopterin concentration (96.20 ± 40.41 vs 118.76 ± 27.84 μmol mol^-1 creatinine) were recorded. Conversely, the antioxidant capacity significantly decreased (3.423 ± 0.089 vs 3.015 ± 0.284 mM) after immersion.

CONCLUSION

Overproduction of ROS and consequent oxidative damage to lipids of membrane and antioxidant capacity decreasing reflect also a hypoxic condition, which in the breath-hold diving typically occurs in the last few meters below the surface. iNOS produces NO in large quantities under the examined extreme conditions. Neopterin and creatinine concentration level increased, suggesting an "impairment of renal function" as a likely physiological response to PaO₂ variations during dive activity.

Effects of enzymatically modified isoquercitrin in supplementary protein powder on athlete body composition: a randomized, placebo-controlled, double-blind trial

Background

Enzymatically modified isoquercitrin (EMIQ), a water-soluble quercetin, has been shown to intensify muscle hypertrophy in mice. We investigated the effect of EMIQ in supplementary protein powder on athlete body composition.

Methods

Forty Japanese males who played American football (age: 19.8 ± 1.4 years; body height: 174.1 ± 6.0 cm; body mass: 75.5 ± 10.7 kg) were assigned to a randomized, placebo-controlled, double-blind trial of parallel group. Participants received either EMIQ in whey protein (EW, n = 19) or contrast whey protein (W, n = 20) 6 days per week over 4 months. Body composition was assessed using dual-energy X-ray absorptiometry. Markers of oxidative stress, derivatives of reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP), were assessed using a free radical analytical system. Data were analyzed using a univariate and repeated measures general model statistics.

Results

After 4 months, changes in lower limb fat-free mass and muscle mass were significantly greater in the EW group than in the W group (mean change ±95% CI; W: 324.1 ± 284.3, EW: 950.3 ± 473.2, p = 0.031, W: 255.7 ± 288.6, EW: 930.9 ± 471.5, p = 0.021, respectively). Moreover, the EW group exhibited a significantly higher BAP/d-ROMs ratio, antioxidation index, than the W group after 4 months (mean change ± SD; W: 8.8 ± 1.1, EW: 10.3 ± 2.8; p = 0.028). No significant differences in body mass, lean body mass, fat mass, or lower limb fat mass were observed between the groups.

Conclusion

Ingestion of EMIQ in supplementary protein powder for 4 months exerts antioxidant effects and increases muscle mass among American football players.

Trial registration

University Hospital Medical Information Network Clinical Trial Registry, UMIN000036036. Retrospectively registered in 2019.

Acute Effects of Hesperidin in Oxidant/Antioxidant State Markers and Performance in Amateur Cyclists

Human and animal studies have shown that Hesperidin has the ability to modulate antioxidant and inflammatory state and to improve aerobic performance. The main objective of this study was to assess whether the acute intake of 500 mg of 2S-Hesperidin (Cardiose^®) improves antioxidant status, metabolism, and athletic performance, during and after a rectangular test (aerobic and anaerobic effort). For this, a crossover design was used in 15 cyclists (>1 year of training), with one week of washout between placebo and Cardiose^® supplementation. After the intervention, significant differences in average power (+2.27%, p = 0.023), maximum speed (+3.23%, p = 0.043) and total energy (∑ 4 sprint test) (+2.64%, p = 0.028) between Cardiose^® and placebo were found in the best data of the repeated sprint test. Small changes were also observed in the activity of catalase, superoxide dismutase, reduced glutathione concentration and oxidized/reduced glutathione (GSSG/GSH) ratio, as well as the lipoperoxidation products (thiobarbituric acid reactive substances; TBARS), at different points of the rectangular test, although not significant. Our findings showed improvements in anaerobic performance after Cardiose^® intake, but not in placebo, suggesting the potential benefits of using Cardiose^® in sports with a high anaerobic component.

Metabonomic Analysis of the Therapeutic Effects of Chinese Medicine Sanqi Oral Solution on Rats With Exhaustive Exercise

Exhaustive exercise has emerged as an important health issue nowadays. This study was designed to assess the metabolite abnormalities of rats after exhaustive exercise and the holistic efficacy of Chinese medicine Sanqi oral solution (SQ). Through exhaustive swimming, the exhaustive exercise model in rats was established. Thirty male Sprague–Dawley rats were randomly divided into control, model, and treatment groups. SQ (12 mL·kg⁻¹·d⁻¹) or 0.9% saline solution was administrated orally by gastric gavage. After 4 weeks, serum samples were collected for biochemical measurements and ultra performance liquid chromatography (UPLC)/quadrupole time-of-flight mass spectrometry (Q-TOF-MS)-based metabonomic study. It was found that rats with SQ intervention showed longer exhaustive swimming time (P < 0.05) than model rats, with an average of 1,160.36 ± 123.89 s in SQ group and 906.57 ± 172.11 s in model group. Among the biochemical indices, the levels of creatine kinase isoenzyme, lactate dehydrogenase, and glucose of exhaustive exercise rats increased, whereas levels of creatine kinase, urea, triglyceride, and total cholesterol decreased. These biochemical indices came normal after SQ administration, except for triglyceride. Twenty-seven potential biomarkers belonging to sphingolipids, phospholipids, fatty acids, amino acid, and other classes were identified in serum. This study indicated that SQ exerted protective effects on exhaustive exercise by significantly prolonging the swimming endurance time. The metabonomic-based findings of the metabolic state and analysis of potential biomarkers in serum well correlated with biochemical assessment, confirming that SQ had a definite efficacy. Moreover, the shifts in lipid-related metabolites and glycolytic pathway suggested that SQ may serve as a potential supplementation in sports nutrition for its pharmacological effect of regulating energy metabolism as well as improving signal transduction and muscle-cell physiological functions.

Consumption of an Anthocyanin-Rich Extract Made From New Zealand Blackcurrants Prior to Exercise May Assist Recovery From Oxidative Stress and Maintains Circulating Neutrophil Function: A Pilot Study

Aim: To evaluate blackcurrant anthocyanin-rich extract (BAE) consumption on time- and dose-dependent plasma anthocyanin bioavailability and conduct a pilot study to explore the potential effect of BAE in promoting recovery from exercise-induced oxidative stress, and maintenance of circulating neutrophil function.

Methods: Time- and dose-dependent blackcurrant anthocyanin bioavailability was assessed using LC-MS in 12 participants over 6 h after the ingestion of a placebo or BAE containing 0.8, 1.6, or 3.2 mg/kg total anthocyanins. In a separate pilot intervention exercise trial, 32 participants consumed either a placebo or 0.8, 1.6, or 3.2 mg/kg BAE (8 individuals per group), and then 1 h later performed a 30 min row at 70% VO₂max. Blood was collected during the trial for oxidative, antioxidant, inflammatory, and circulating neutrophil status.

Results: Consumption of BAE caused a time- and dose-dependent increase in plasma anthocyanins, peaking at 2 h after ingestion of 3.2 mg/kg BAE (217 ± 69 nM). BAE consumed 1 h prior to a 30 min row had no effect on plasma antioxidant status but hastened the recovery from exercise-induced oxidative stress: By 2 h recovery, consumption of 1.6 mg/kg BAE prior to exercise caused a significant (P < 0.05) 34 and 32% decrease in post-exercise plasma oxidative capacity and protein carbonyl levels, respectively, compared to placebo. BAE consumption prior to exercise dose-dependently attenuated a small, yet significant (P < 0.01) transient 13 ± 2% decline in circulating neutrophils observed in the placebo group immediately post-exercise. Furthermore, the timed consumption of either 1.6 or 3.2 mg/kg BAE attenuated a 17 ± 2.4% (P < 0.05) decline in neutrophil phagocytic capability of opsonised FITC-Escherichia coli observed 6 h post-exercise in the placebo group. Similarly, a dose-dependent increase in neutrophil surface expression of complement receptor-3 complex (CR3, critical for effective phagocytosis of opsonised microbes), was observed 6 h post-exercise in both 1.6 and 3.2 mg/kg BAE intervention groups.

Conclusions: Consumption of BAE (>1.6 mg/kg) 1 h prior to exercise facilitated recovery from exercise-induced oxidative stress and preserved circulating neutrophil function. This study provides data to underpin a larger study designed to evaluate the efficacy of timed BAE consumption on post-exercise recovery and innate immunity.

Regular exercise, overweight/obesity and sedentary lifestyle cause adaptive changes in thiol-disulfide homeostasis

Dynamic thiol-disulfide homeostasis is considered to have critical roles in maintenance of physiological functioning. We aimed to reveal whether there is any specific aberration in thiol-disulfide homeostasis in three distinct categories of individuals, including those who 1) exercise regularly (fitness group), 2) have a sedentary lifestyle (sedentary group) and 3) are overweight or obese (overweight/obese group). 72 male individuals were included in the study, 21 of whom were in fitness group, 28 of whom were overweight or obese and 23 of whom had a sedentary lifestyle. Plasma native thiol (-SH) and total thiol [(-SH) + (-S-S-)] levels were quantitatively determined. Total thiol levels in sedentary group were significantly lower than those in overweight/obese (p<0.05) and fitness groups (p<0.001). Also, disulfide values in fitness group were significantly higher than those in sedentary and overweight/obese groups (p<0.005, p<0.05). On the other hand, disulfide level, reduced and oxidized thiol ratios and oxidation/reduction ratio in fitness group differed significantly from the other groups (p<0.05). Thiol-disulfide homeostasis varies depending on lifestyle. The results of our study indicate that higher total thiol and disulfide levels are conspicuously distinctive features of thiol-disulfide homeostasis in individuals exercising regularly.

A new oxidative stress indicator: Effect of 5-hydroxytryptophan on thiol-disulfide homeostasis in exercise

OBJECTIVES

The aim of the present study was to evaluate the relationship between exercise and both 5-hydroxytryptophan and oxidative stress using thiol-disulfide homeostasis via what is likely a novel biomarker.

METHODS

Male albino Wistar rats (n = 32) were randomly divided into four groups as follows: control, exercise group, 5-hydroxytryptophan group (5H), and 5-HTP + exercise group (5Hex). Exercise and 5-HTP administration (25mg/kg per d) were performed 5d/wk for 10 wk. After completion of the experimental protocol, to determine oxidative stress parameters, serum total thiol and native thiol concentrations were measured. Dynamic disulfide status, reduced thiol, oxidized thiol (OT), and thiol oxidation reduction percentage ratios were compared between the groups. The methods used in the present study to measure dynamic thiol-disulfide homeostasis as calorimetric and duplex quantities were developed in 2014. These new methods are simple, reliable, and sensitive, with both high linearity and repeatability.

RESULTS

Compared with the control group, serum dynamic disulfide levels were significantly lower in the 5H group and highest in the control group. The lowest OT and the highest reduced thiol rates were determined to be in the 5H group. The highest OT value was found in the 5Hex group. Thiol oxidation reduction values were found to be highest in the 5H group and lowest in the 5Hex group.

CONCLUSIONS

Both 5-HTP and moderate exercise seem to be significantly effective in inhibiting oxidative damage. In addition, the new oxidative stress measurement method used in this study is a promising practical and useful method to evaluate and improve the performance of athletes.

Effect of ingesting carbohydrate only or carbohydrate plus casein protein hydrolysate during a multiday cycling race on left ventricular function, plasma volume expansion and cardiac biomarkers

PURPOSE

Multiday racing causes mild left ventricular (LV) dysfunction from day 1 that persists on successive days. We evaluated ingesting casein protein hydrolysate-carbohydrate (PRO) compared with carbohydrate-only (CHO) during a 3-day mountain bike race.

METHODS

Eighteen male cyclists were randomly assigned to ingest 6.7% carbohydrate without (CHO) or with 1.3% casein hydrolysate (PRO) during racing (~ 4-5 h/day; 68/71/71 km). Conventional LV echocardiography, plasma albumin content, plasma volume (PV) and blood biomarkers were measured before day 1 and post race on day 3.

RESULTS

Fourteen cyclists (n = 7 per group) completed the race. PV increased in CHO (mean increase (95% CI), 10.2% (0.1 to 20.2)%, p = 0.045) but not in PRO (0.4% (- 6.1 to 6.9)%). Early diastolic transmitral blood flow (E) was unchanged but deceleration time from peak E increased post race (CHO: 46.7 (11.8 to 81.6) ms, p = 0.019; PRO: 24.2 (- 0.5 to 48.9) ms, p = 0.054), suggesting impaired LV relaxation. Tissue Doppler mitral annular velocity was unchanged in CHO, but in PRO septal early-to-late diastolic ratio decreased (p = 0.016) and was compensated by increased lateral early (p = 0.034) and late (p = 0.012) velocities. Systolic function was preserved in both groups; with increased systolic lateral wall velocity in PRO (p = 0.002). Effect size increase in serum creatine kinase (CK) activity, CK-MB and C-reactive protein concentrations was less in PRO than CHO (Cohen's d mean ± SD, PRO: 2.91 ± 2.07; CHO: 7.56 ± 4.81, p = 0.046).

CONCLUSION

Ingesting casein hydrolysate with carbohydrate during a 3-day race prevented secondary hypervolemia and failed to curb impaired LV relaxation despite reducing tissue damage and inflammatory biomarkers. Without PV expansion, systolic function was preserved by lateral wall compensating for septal wall dysfunction.

Association of Healthy Eating Index and oxidative stress in adolescent volleyball athletes and non-athletes

OBJECTIVES

The objective of this study was to compare the relationship between the Healthy Eating Index and oxidative stress parameters in adolescent athletes and non-athletes.

METHODS

A cross-sectional study was carried out with 18 adolescent male and female volleyball athletes who were paired with 15 adolescent non-athletes. Body fat percentage, food intake, free radical production, antioxidant enzyme activity, and thiol and protein damage were measured.

RESULTS

In the Healthy Eating Index assessment, the food quality of 72.7% of the sample was classified as low, and no participant was found to have good food quality. The mean intake of vitamins A and E was below recommendations in both groups and sexes; however vitamin C intake was appropriate for the age group. Increased free radical production was observed in the athletes' erythrocytes (p<0.001), accompanied by lower levels of plasma reduced glutathione (p = 0.01), but there were no correlations between Healthy Eating Index and oxidative stress parameters or between body composition, vitamin A, C and E intake and oxidative stress.

CONCLUSIONS

The sample's diet quality was classified as low and, despite the fact that there was greater production of free radicals in the athletes' erythrocytes and plasma, in addition to lower levels of plasma reduced glutathione , there was no correlation between Healthy Eating Index and oxidative stress.

Protective Role of Vitamin C Intake on Muscle Damage in Male Adolescents Performing Strenuous Physical Activity

BACKGROUND:

Strenuous non-regular exercise increases reactive oxygen species ROS level leading to an impaired balance between the endogenous antioxidant defence system and the free radicals production. Antioxidants intake can detoxify the peroxides produced during exercise, attenuating the inflammatory responses and therefore may prevent exercise-induced muscle damage.

AIM:

The purpose of this study was to determine the role of vitamin C intake in attenuating markers of muscle damage, oxidative stress and inflammatory responses in male adolescents performing the non-regular strenuous exercise.

MATERIAL AND METHODS:

Twenty recreationally active male adolescents were assigned to participate in the study. Eligible subjects performed strenuous recreational exercise (2-3 times per week) were randomly divided into two groups: The vitamin C (VC) group that consumed 500 mg of capsulated vitamin C after breakfast for a period of 90 days and the placebo (PL) group that consumed identical capsules in form and aspect that contained 500 mg of maltodextrin for the same period. Aspartate aminotransferase (AST), creatine kinase (CK), lactate dehydrogenase (LDH) were assessed for muscle damage. Malondialdehyde (MDA) was evaluated as a marker of lipid peroxidation. Plasma creatinine, uric acid and urea were determined to monitor kidney function. C-reactive protein, a marker of systemic inflammation was also measured.

RESULTS:

In comparison between PL and VC groups, the plasma concentrations of muscle damage markers, oxidative stress markers, kidney function and inflammatory markers showed no significant difference in their baseline values (P > 0.05). The plasma concentrations of CK, LDH, MDA, urea, uric acid and CRP were significantly decreased in the VC group (P < 0.05) as compared to their values before the intake of vitamin C.

CONCLUSION:

The present results support the intake of vitamin C as an antioxidant for attenuating exercise-induced muscle damage, oxidative stress and inflammatory markers in male adolescents performing the strenuous physical activity.

A novel biomarker explaining the role of oxidative stress in exercise and l-tyrosine supplementation: thiol/disulphide homeostasis

The present study aimed to evaluate the relationship between exercise and both l-tyrosine and oxidative stress using thiol/disulphide homeostasis via a novel biomarker in rats. Following the completion of the exercise and l-tyrosine protocol, serum total thiol, native thiol, and disulphide concentrations were determined using a novel automated measurement method. Compared with the control group, serum dynamic disulphide levels were significantly lower in the E group (116.75 ± 10.49; p < .05) and the highest in the LT group (151.0 ± 5.84). The lowest oxidised thiol (49.75 ± 6.18; p = .087) and the highest reduced thiol (75.38 ± 3.16; p = .079) rates were determined to be in the E group. The highest oxidised thiol value was observed in the LT group. Exercise positively affects thiol/disulphide homeostasis, which is a novel indicator of oxidant-antioxidant parameters. Additionally, l-tyrosine appears to be more convenient combined with exercise. The new method used in our study proposes a promising, practical, and useful method for assessing the oxidative stress parameters.

The Ability of Exercise-Associated Oxidative Stress to Trigger Redox-Sensitive Signalling Responses

In this review, we discuss exercise as an oxidative stressor, and elucidate the mechanisms and downstream consequences of exercise-induced oxidative stress. Reactive oxygen species (ROS) are generated in the mitochondria of contracting skeletal myocytes; also, their diffusion across the myocyte membrane allows their transport to neighbouring muscle tissue and to other regions of the body. Although very intense exercise can induce oxidative damage within myocytes, the magnitudes of moderate-intensity exercise-associated increases in ROS are quite modest (~two-fold increases in intracellular and extracellular ROS concentrations during exercise), and so the effects of such increases are likely to involve redox-sensitive signalling effects rather than oxidative damage. Therefore, the responses of muscle and non-muscle cells to exercise-associated redox-sensitive signalling effects will be reviewed; for example, transcription factors such as Peroxisome Proliferator Activated Receptor-gamma (PPARγ) and Liver X-Receptor-alpha (LXRα) comprise redox-activable signalling systems, and we and others have reported exercise-associated modulation of PPARγ and/or LXRα-regulated genes in skeletal myocyte and in non-muscle cell-types such as monocyte-macrophages. Finally, the consequences of such responses in the context of management of chronic inflammatory conditions, and also their implications for the design of exercise training programmes (particularly the use of dietary antioxidants alongside exercise), will be discussed.