Changes in oxidative stress markers and biological markers of muscle injury with aging at rest and in response to an exhaustive exercise

The interplay of exercise and polyphenols in cancer treatment: A focus on oxidative stress and antioxidant mechanisms

Exercise has been demonstrated to induce an elevated production of free radicals, leading to the onset of oxidative stress. Numerous studies highlight the positive impacts of aerobic exercise, primarily attributed to the increase in overall antioxidant capacity. The evidence suggests that engaging in aerobic exercise contributes to a reduction in the likelihood of advanced cancer and mortality. Oxidative stress occurs when there is an imbalance between the generation of free radicals and the collective antioxidant defense system, encompassing both enzymatic and nonenzymatic antioxidants. Typically, oxidative stress triggers the formation of reactive oxygen or nitrogen species, instigating or advancing various issues in cancers and other diseases. The pro-oxidant-antioxidant balance serves as a direct measure of this imbalance in oxidative stress. Polyphenols contain a variety of bioactive compounds, including flavonoids, flavanols, and phenolic acids, conferring antioxidant properties. Previous research highlights the potential of polyphenols as antioxidants, with documented effects on reducing cancer risk by influencing processes such as proliferation, angiogenesis, and metastasis. This is primarily attributed to their recognized antioxidant capabilities. Considering the extensive array of signaling pathways associated with exercise and polyphenols, this overview will specifically focus on oxidative stress, the antioxidant efficacy of polyphenols and exercise, and their intricate interplay in cancer treatment.

Association between dietary and behavioral-based oxidative balance score and phenotypic age acceleration: a cross-sectional study of Americans

OBJECTIVES

In light of the rise in the global aging population, this study investigated the potential of the oxidative balance score (OBS) as an indicator of phenotypic age acceleration (PhenoAgeAccel) to better understand and potentially slow down aging.

METHODS

Utilizing data from the National Health and Nutrition Examination Survey collected between 2001 and 2010, including 13,142 United States adults (48.7% female and 51.2% male) aged 20 and above, OBS and PhenoAgeAccel were calculated. Weighted generalized linear regression models were employed to explore the associations between OBS and PhenoAgeAccel, including a sex-specific analysis.

RESULTS

The OBS demonstrated significant variability across various demographic and health-related factors. There was a clear negative correlation observed between the higher OBS quartiles and PhenoAgeAccel, which presented sex-specific.

RESULTS

the negative association between OBS and PhenoAgeAccel was more pronounced in male than in female. An analysis using restricted cubic splines revealed no significant non-linear relationships. Interaction effects were noted solely in the context of sex and hyperlipidemia.

CONCLUSIONS

A higher OBS was significantly associated with a slower aging process, as measured by lower PhenoAgeAccel. These findings underscore the importance of OBS as a biomarker in the study of aging and point to sex and hyperlipidemia as variables that may affect this association. Additional research is required to confirm these results and to investigate the biological underpinnings of this relationship.

Measures of Oxidative Status Markers in Relation to Age, Sex, and Season in Sick and Healthy Captive Asian Elephants in Thailand

Oxidative stress is a pathological condition that can have adverse effects on animal health, although little research has been conducted on wildlife species. In this study, blood was collected from captive Asian elephants for the assessment of five serum oxidative status markers (reactive oxygen species (ROS) concentrations; malondialdehyde, MDA; albumin; glutathione peroxidase, GPx; and catalase) in healthy (n = 137) and sick (n = 20) animals. Health problems consisted of weakness, puncture wounds, gastrointestinal distress, eye and musculoskeletal problems, and elephant endotheliotropic herpesvirus hemorrhagic disease (EEHV-HD). Fecal samples were also collected to assess glucocorticoid metabolites (fGCMs) as a measure of stress. All data were analyzed in relation to age, sex, sampling season, and their interactions using generalized linear models, and a correlation matrix was constructed. ROS and serum albumin concentrations exhibited the highest concentrations in aged elephants (>45 years). No sex differences were found for any biomarker. Interactions were observed for age groups and seasons for ROS and catalase, while GPx displayed a significant interaction between sex and season. In pairwise comparisons, significant increases in ROS and catalase were observed in summer, with higher ROS concentrations observed only in the adult female group. Lower catalase activity was exhibited in juvenile males, subadult males, adult females, and aged females compared to subadult and adult elephants (males and females) in winter and the rainy season. There was a positive association between catalase activity and fGCMs (r = 0.23, p < 0.05), and a number of red blood cell parameters were positively associated with several of these biomarkers, suggesting high oxidative and antioxidative activity covary in red cells (p < 0.05). According to health status, elephants with EEHV-HD showed the most significant changes in oxidative stress markers, with MDA, GPx, and catalase being higher and albumin being lower than in healthy elephants. This study provides an analysis of understudied health biomarkers in Asian elephants, which can be used as additional tools for assessing the health condition of this species and suggests age and season may be important factors in data interpretation.

Does Opuntia ficus-indica Juice Supplementation Improve Biochemical and Cardiovascular Response to a 6-Minute Walk Test in Type 2 Diabetic Patients?

Background and objectives: The purpose of this study was to evaluate the effect of Opuntia ficus-indica juice (OFIJ) on performance and biochemical and physiological responses to a 6 min walking test (6MWT) in diabetic patients. Materials and Methods: Twenty diabetic patients performed a 6MWT at 07:00 h. During each test session, they were asked to drink 70 mL/day of natural OFIJ or placebo (PLA) for 4 days. Results: the results showed that cardiovascular parameters increased significantly after the 6MWT under both conditions. While, cortisol, HbA1c, cholesterol total (CT), triglycerides (TG), as well as low-density lipoprotein (LDL) were not modified between without and with supplementation. Likewise, no significant variation in performance was observed for PLA and OFIJ (p > 0.05). The cardiovascular parameters (heart rate max (HRmax), diastolic blood pressure (DBP), and systolic blood pressure (SBP)), lipid profile (CT, TG, LDL, and high-density lipoprotein HDL), hormonal parameters (insulin and glucagon), HbA1c and lactate ([La]) did not present any significant modification either between PLA or OFIJ (p > 0.05). Muscle-damage markers (creatine kinase (CK) and lactate dehydrogenase (LDH)], cortisol, and liver parameters (i.e., oxidative stress marker, γGT, and total bilirubin) as well as glucose (GLC) were affected by supplementation (p < 0.05) before and after the 6MWT, but this change was significant only for OFIJ (p < 0.05). Conclusion: OFIJ had an antioxidant capacity, improved performance of the 6MWT, and reduced muscle-damage markers and glucose level in type 2 diabetic patients.

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.

Impact of Hydrotherapy on Antioxidant Enzyme Activity in an Elderly Population

Oxidative stress is defined as the imbalance between reactive species and antioxidant agents. One of the effects of oxidative stress is the normal process of cellular aging that stems from the accumulation of tissue damage. Epidemiological studies show that regular physical exercise prevents the injuries caused by aging. The objective was to evaluate whether the practice of hydrotherapy, in an elderly population, positively influenced the activity of the enzymes superoxide dismutase, glutathione peroxidase and reductase that act by reducing reactive species in the body. The study involved 37 participants aged ≥ 60 years, of both sexes, divided into experimental and control groups. The experimental group performed 15 hydrotherapy sessions. Enzyme activity was evaluated in two moments: T0-before the first session, and T1-after the last session, with blood collections conducted in both. In T1, there was a significant increase vs. T0 of glutathione peroxidase activity (57.72 ± 19.99 vs. 48.14 ± 17.22 U/g Hb) and glutathione reductase activity (100.18 ± 30.85 vs. 78.44 ± 21.26 U/L). Both sexes tended to show higher values at T1. We concluded that hydrotherapy proved to be a positive stimulus for the enzymatic antioxidant activity of the elderly, suggesting that a regular and moderate practice of physical exercise induces better and higher quality of life.

Ergogenic property of Morinda citrifolia L. leaf extract affects energy metabolism in obese Sprague Dawley rats

Ergogenic property is the ability to enhance capacity for physical activities through efficient production of energy and is potentially beneficial in weight management for the obese. In this study, ergogenic property of Morinda citrifolia leaf's extract (MCL) was evaluated using AMP-activated protein kinase (AMPK) activity and high fat diet-induced obese rats. Findings from the study showed that MCL demonstrated ergogenic activity via enhancement of AMPK activity using L6 skeletal muscle cell line. Interestingly, the result also revealed that rats treated with the intermediate dosage of MCL experienced the lowest % weight gain. The rats fed the highest dose of 200 mg/kg BW MCL demonstrated the longest swimming time of approximately three times that of green tea and caffeine-fed rats. The highest dose fed rats were also found to have lower glucose and lactate levels, suggesting that energy metabolism was more effective in these rats. In addition, lactate dehydrogenase and creatinine kinase activities, the muscle injury indicators, were found to be the lowest in rats fed the highest MCL dose. The same effect was not seen in rats fed either caffeine or green tea, indicating that MCL treatment is may be protective of the rats' muscles. It was also shown that MCL consisted of various flavonoids with epicatechin, catechin, and quercetin that may be responsible for the effects measured. In conclusion, improvements were seen in rats fed MCL in terms of weight management, endurance capacity, energy metabolism, and muscle injury parameters. PRACTICAL APPLICATIONS: Results of the study revealed that Morinda citrifolia leaf has great potential to be used as functional ingredient in the development of designer food/drink as ergogenic aid for both obese and non-obese individuals. Morinda citrifolia leaf could help in the weight management of obese people and enhance endurance capacity and energy metabolism in active individuals.

Effects of High Intensity Exercise on Oxidative Stress and Antioxidant Status in Untrained Humans: A Systematic Review

Participation in exercise promotes health. High intensity exercise (HIE) has become increasingly popular among the general population, however, its effects on exercise-induced oxidative stress and antioxidant status in untrained humans is not clear. The aim of this systematic review was to investigate the influence of HIE on oxidative stress and antioxidant status in untrained humans. Web of Science, PubMed, MEDLINE, and Scopus were searched until March 2021. A methodological quality assessment valuation/estimation was additionally carried out in the final sample of studies. Following the PRISMA selection process, 21 studies were finally included. There was strong evidence that acute oxidative stress following the cessation of HIE exists when compared to resting states. The HIE-induced oxidative stress is transient and is most likely restored to normal levels within 24 h due to the stimulated endogenous antioxidant system whose response was lagging and lasting. Physically active humans had better antioxidant systems and suffered less oxidative stress after HIE. A physically active lifestyle was considered to enhance antioxidant capacity. For untrained humans, HIE with intensities above 70% VO₂max are proposed for initial exercise levels based on the findings reported here.

The Combined Effects of 6 Weeks of Jump Rope Interval Exercise and Dark Chocolate Consumption on Antioxidant Markers in Obese Adolescent Boys

Research has shown that both dark chocolate and exercise training may have favorable effects on antioxidant function in obese cohorts. However, their combined effect has not been established. We assessed the influences of six weeks of dark chocolate consumption combined with jump rope exercise on antioxidant markers in adolescent boys with obesity. Fifty adolescent boys with obesity (age = 15 ± 1 years) were randomly assigned into one of four groups; jump rope exercise + white chocolate consumption (JW; n = 13), jump rope exercise + dark chocolate consumption (JD; n = 13), dark chocolate consumption (DC; n = 12), or control (C; n = 12). Two participants dropped out of the study. Participants in JW and JD groups performed jump rope exercise three times per week for six weeks. Participants in the DC and JD groups consumed 30 g of dark chocolate containing 83% of cocoa during the same period. Serum concentrations of superoxide dismutase (SOD), total antioxidant capacity (TAC), glutathione peroxidase (GPx), and thiobarbituric acid reactive substances (TBARS) were evaluated prior to and after the interventions. All 3 intervention groups noted significant (p < 0.01) increases in serum concentrations of TAC, SOD, and GPx from baseline to post-test. In contrast, all intervention groups showed significantly reduced serum concentrations of TBARS from pre- to post-test (p ≤ 0.01). Bonferroni post hoc analysis revealed that post-test serum concentrations of TAC in the JD group were significantly greater than C (p < 0.001), DC (p = 0.010), and JW (p < 0.001) groups. In addition, post-test serum concentrations of SOD in the JD group were significantly greater than C group (p = 0.001). Post-test serum concentrations of GPx in the JD group were significantly greater than C (p < 0.001), DC (p = 0.021), and JW (p = 0.032) groups. The post-test serum concentrations of TBARS in the JD group was significantly lower than C (p < 0.001). No other significant between-group differences were observed. The current study provides evidence that dark chocolate consumption in combination with jump rope exercise is more efficient in improving antioxidant capacity than dark chocolate consumption or jump rope exercise alone among obese adolescent boys.

Effect of Schisandra chinensis Baillon extracts and regular low-intensity exercise on muscle strength and mass in older adults: a randomized, double-blind, placebo-controlled trial

BACKGROUND

Studies suggest that Schisandra chinensis Baillon (Sc) may enhance muscle strength and mass because of its anti-inflammatory and antioxidant properties.

OBJECTIVES

We aimed to examine the effects and safety of consumption of Sc extract (SCe) for 12 wk on muscle strength and mass in older adults with relatively low muscle mass who do low-intensity exercise.

METHODS

A randomized, double-blind, placebo-controlled trial was performed in adults >50 y of age. Fifty-four participants were randomly assigned into 2 groups and, for 12 wk, received either 1 g SCe/d or a placebo. All participants were required to walk for 30-60 min/d for >3 d/wk during the trial period. At baseline and at 4 and 12 wk after treatment, the participants were examined for knee extension strength using Biodex isokinetic dynamometers, handgrip strengths, and body composition, and blood tests were performed. The Euro-QoL-5D (EQ-5D) questionnaire and the FFQ were administered at baseline and at 12 wk after treatment. Physical activity was assessed using a self-recorded daily exercise log and an accelerometer during the study.

RESULTS

SCe supplementation over 12 wk caused a higher increase in right knee extensor strength by 10.2 Nm (95% CI: 3.7, 16.8 Nm; P = 0.003) and left knee extensor strength by 6.7 Nm (95% CI: 0.3, 13.1 Nm; P = 0.041) than did the placebo. However, no differences were observed in the muscle mass, anti-inflammatory markers, antioxidative markers, and EQ-5D score between the groups. None of the participants experienced adverse events.

CONCLUSIONS

SCe supplementation may enhance skeletal muscle strength but not mass in older adults who perform low-intensity exercise. This trial was registered at clinicaltrials.gov as NCT03402308.

Effect of Different Exercise Modalities on Oxidative Stress: A Systematic Review

Exercise-induced benefits are being increasingly recognized in promoting health and preventing diseases. However, initial adaption to exercise response can have different effects on cells, including an increase in the formation of oxidants and inflammatory mediators that ultimately leads to oxidative stress, but this scenario depends on the exercise type and intensity and training status of the individual. Therefore, we aimed to understand the effect of different types of exercise on oxidative stress. Indeed, exercise-induced minimum oxidative stress is required for regulating signaling pathways. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, a search for relevant articles was carried out on PubMed/Medline, ISI Web of Science, and Google Scholar using a broad range of synonyms such as oxidants, reactive oxygen species (ROS), oxidative stress, exercise, physical training, aerobic exercise, and strength exercise until 2019. This study selected a total of 18 articles for assessing the oxidative damage using various parameters such as malondialdehyde (MDA), protein carbonyl (PCO), and F1-isoprostanes and enzymatic antioxidants. We observed that any type of exercise can increase the oxidative damage in an exercise type and intensity manner. Further, the training status of the individual and specific oxidative damage marker plays a crucial role in predicting earlier oxidative damage in the exercise condition. However, some of the studies that we included for review did not perform follow-up evaluations. Therefore, follow-up programs using larger numbers need to be performed to confirm our findings.

Evaluation of the Efficacy of Supplementation with Planox® Lemon Verbena Extract in Improving Oxidative Stress and Muscle Damage: A Randomized Double-Blind Controlled Trial

Excessive exercise load can cause muscle soreness and fatigue, as well as inflammation and oxidative stress. Lemon verbena (Aloysia triphylla; Lippia citriodora) is often used as a spice in tea or beverages. Its leaves are rich in polyphenols, which have antioxidant and anti-inflammatory bioactivities. In the present study, we investigated whether supplementation with Planox® lemon verbena extract (LVE) could improve muscle damage and biochemical indicators after exhaustive exercise challenge. All subjects (30 males and 30 females) underwent a double-blind trial and were randomly divided into a placebo group (0 mg/human/day) and an LVE supplement group (400 mg/human/day), with gender-equal distribution. All subjects started supplementation 10 days before exhaustive exercise and continued it until all tests were completed. Before the intervention, after the exhaustive exercise, and on the following 3 days, the participants underwent 12-minute Cooper running/walking; blood collection; assessments of pain, muscle stiffness, maximum jump heights, and isometric maximum muscle strength. The results showed that supplementation with LVE effectively increased GPx and reduced CK, IL-6, 8-OHdG and muscle pain after the exhaustive exercise, but it had significant effect on strength recovery. In summary, LVE is a safe and edible natural plant extract that can reduce muscle damage and soreness after exercise. This trial was registered at clinicaltrials.gov as NCT04742244.

Prevalence of work-related musculoskeletal disorders among Egyptian printing workers evidenced by using serum biomarkers of inflammation, oxidative stress, muscle injury, and collagen type I turnover

OBJECTIVE

Printing workers experience a high rate of musculoskeletal disorders (MSDs). This study aims to determine the prevalence of MSDs, estimate serum biomarkers denoting musculoskeletal tissue changes, and determine some individual risk factors for MSDs among Egyptian printing workers.

METHODS

Eighty-five male printing workers and 90 male administrative employees (control group) were recruited from a printing press in Giza. A validated version of the standardized Nordic questionnaire was used. Serum biomarkers of inflammation (interleukin (IL)-1α, IL-1β, IL-6, tumor necrosis factor (TNF)-α, and C-reactive protein (CRP)), cell stress or injury (malondialdehyde (MDA) and creatine kinase skeletal muscle (CK-MM)), and collagen metabolism (collagen-I carboxy-terminal propeptide (PICP) and type-I collagen cross-linked C-telopeptide (CTx)) were measured for all participants.

RESULTS

This study showed a significant (p < 0.001) prevalence of the musculoskeletal symptoms (76.5%) and significant (p < 0.001) elevation in the levels of all measured biomarkers among the printing workers (means ± SD: IL-1α = 1.55 ± 0.9, IL-1β = 1.53 ± 0.87, IL-6 = 1.55 ± 0.85, TNF-α = 4.9 ± 2.25, CRP = 6.78 ± 3.07, MDA = 3.41 ± 1.29, CK-MM = 132.47 ± 69.01, PICP = 103.48 ± 36.44, and CTx = 0.47 ± 0.16) when compared with their controls (prevalence: 34.4%; means ± SD: IL-1α = 0.88 ± 0.61, IL-1β = 0.96 ± 0.72, IL-6 = 1.03 ± 0.75, TNF-α = 2.56 ± 1.99, CRP = 2.36 ± 1.1, MDA = 0.85 ± 0.21, CK-MM = 53.48 ± 33.05, PICP = 56.49 ± 9.05, and CTx = 0.31 ± 0.06). Also, significant (p < 0.001) positive strong associations were observed between age, body mass index (BMI), and the duration of employment with all measured biomarkers, where all correlation coefficients were >0.7.

CONCLUSION

Printing workers suffer a high prevalence of work-related MSDs that might be related to some individual factors (age, BMI, and duration of employment). Consequently, preventive ergonomic interventions should be applied. Further studies should be done to elucidate the link between tissue changes and detected biomarkers to follow the initiation and progression of MSDs and study the effectiveness of curative interventions.

Chlorella vulgaris Ameliorates Oxidative Stress and Improves the Muscle Regenerative Capacity of Young and Old Sprague-Dawley Rats

Muscle atrophy in ageing is a multifactorial degenerative process impacted by cellular ageing biology, which includes oxidative stress. Chlorella vulgaris is a coccoid green eukaryotic microalga rich in antioxidants. The aim of this study was to determine the effect of C. vulgaris in ameliorating oxidative stress, thus elucidating its mechanism in improving muscle mass, strength and function in young and old rats. Fifty-six male Sprague-Dawley (SD) rats aged 3 months (young) and 21 months (old) were divided into three groups: Group 1 (control) was given distilled water; Group 2 was treated with 150 mg/kg body weight (BW) of C. vulgaris; and Group 3 was treated with 300 mg/kg BW of C. vulgaris for three months. Grip and muscle strength and muscle integrity were determined on days 0, 30, 60, and 90 of treatment. Urine and blood were collected on days 0 and 90 of treatment for oxidative stress marker determination, while the gastrocnemius muscles were collected for muscle oxidative stress analysis. Increased grip strength of the front and hind paws was observed in young C. vulgaris-treated rats on days 30, 60, and 90 compared to the untreated control on the same days (p < 0.05). There was a significant increase in lean bone mineral content (BMC) in young rats treated with 300 mg/kg BW C. vulgaris compared to untreated rats on days 30 and 60. The fat mass was significantly decreased in young and old C. vulgaris-treated rats on day 90 compared to the untreated control. The total path was significantly increased for old rats treated with 300 mg/kg BW C. vulgaris on days 60 and 90 compared to day 0. Young and old C. vulgaris-treated rats demonstrated a significant decrease in urinary isoprostane F_2t and plasma creatine kinase-MM (CKMM) compared to the control on day 90. A significant decrease in malondialdehyde (MDA) and 4-hydroxyalkenal (HAE) levels were observed in young and old rats treated with C. vulgaris. C. vulgaris improved the muscle mass, strength, and function in young and old rats. This effect could be due to its potency in ameliorating oxidative stress in the skeletal muscle of young and old rats.

The Impact of Protein Supplementation on Exercise-Induced Muscle Damage, Soreness and Fatigue Following Prolonged Walking Exercise in Vital Older Adults: A Randomized Double-Blind Placebo-Controlled Trial

Background: It is unknown whether protein supplementation can enhance recovery of exercise-induced muscle damage in older adults who have a disturbed muscle protein synthetic response. We assessed whether protein supplementation could attenuate exercise-induced muscle damage and soreness after prolonged moderate-intensity walking exercise in older adults. Methods: In a double-blind, placebo-controlled intervention study, 104 subjects (81% male, ≥65 years) used either a protein (n = 50) or placebo supplement (n = 54) during breakfast and directly after exercise. Within a walking event, study subjects walked 30/40/50 km per day on three consecutive days. Muscle soreness and fatigue were determined with a numeric rating scale, and creatine kinase (CK) concentrations and serum inflammation markers were obtained. Results: Habitual protein intake was comparable between the protein (0.92 ± 0.27 g/kg/d) and placebo group (0.97 ± 0.23 g/kg/d, p = 0.31). At baseline, comparable CK concentrations were found between the protein and the placebo group (110 (IQR: 84–160 U/L) and 115 (IQR: 91–186 U/L), respectively, p = 0.84). Prolonged walking (protein: 32 ± 9 km/d, placebo: 33 ± 6 km/d) resulted in a cumulative increase of CK in both the protein (∆283 (IQR: 182–662 U/L)) and placebo group (∆456 (IQR: 209–885 U/L)) after three days. CK elevations were not significantly different between groups (p = 0.43). Similarly, no differences in inflammation markers, muscle soreness and fatigue were found between groups. Conclusions: Protein supplementation does not attenuate exercise-induced muscle damage, muscle soreness or fatigue in older adults performing prolonged moderate-intensity walking exercise.

Effect of Body Fat Percentage on Muscle Damage Induced by High-Intensity Eccentric Exercise

This study aimed to investigate the impact of percent body fat (%BF) on muscle damage after high-intensity eccentric exercise. Thirty healthy male undergraduates (mean age: 22.0 ± 2 years, height: 176.9 ± 5 cm, weight: 75.8 ± 11.6 kg) participated in this study, and they were classified according to their %BF into a high %fat group (HFG, ≥20%, n = 15) and a low %fat group (LFG, ≤15%, n = 15). For eccentric exercise, two sets of 25 reps were performed on a modified preacher curl machine using the elbow flexor muscle. Maximal isometric strength, muscle soreness (passive and active), creatine kinase (CK), and myoglobin (Mb) were measured as indices of muscle damage. The data were analyzed with repeated measures ANOVA. The results show that there is a significant group–time interaction for both CK and Mb after eccentric exercise (p = 0.007, p = 0.015, respectively), with a greater increase in the HFG than in the LFG. However, there was no significant group–time interaction for maximal isometric strength and muscle soreness (passive and active) (p > 0.05). These results suggest that %BF is a factor that alters the muscle damage indices CK and Mb, which indicate membrane disruption, after eccentric exercise.

Effect of Schisandra Chinensis Extract Supplementation on Quadriceps Muscle Strength and Fatigue in Adult Women: A Randomized, Double-Blind, Placebo-Controlled Trial

The fruit of Schisandra chinensis (SC) is a well-known traditional herb used for pharmacological purposes in Asian countries (e.g., Korea, China, and Japan). In animal studies, SC extract supplementation had beneficial effects on muscle strength and lactate level. However, the effect of SC extract supplementation on skeletal muscle strength and lactate at rest in humans remains unclear. The purpose of this study was to evaluate the effect of SC extract supplementation on quadriceps muscle strength (QMS) and lactate at rest in adult women. Forty five healthy post-menopausal middle-aged women (61.9 ± 8.4 years) were randomly divided into the SC (n = 24) or the placebo group (n = 21). The SC group consumed 1000 mg of SC extract per day, whereas the placebo group consumed 1000 mg of starch per day for 12 weeks. The difference in muscle mass, physical function, and biomarkers and the relative changes between baseline and 12 weeks were evaluated. We used two-factor repeated measures analysis of variance (ANOVA) to determine interaction (group × time) effects for variables. Statistical significance was accepted at p < 0.05. In ANOVA results, QMS (p = 0.001) and lactate level (p = 0.038) showed significant interactions. With paired t-tests, QMS was significantly increased (p < 0.001) and lactate level at rest was significantly decreased (p < 0.05) after 12 weeks in the SC group. However, no interactions were found between the other variables. Supplementation of SC extract may help to improve QMS as well as decrease lactate level at rest in adult women. We believe that SC extract is a health supplement that can support healthy life in this population.

Improving characterization and diagnosis quality of myofascial pain syndrome: a systematic review of the clinical and biomarker overlap with delayed onset muscle soreness

INTRODUCTION

Myofascial pain syndrome (MPS) is one of the most common conditions of chronic musculoskeletal pain, yet its mechanisms are still poorly understood. Delayed Onset Muscle Soreness (DOMS) is also a regional pain syndrome that has clinical similarities to MPS, but has been better investigated. Emerging research suggests that DOMS may be a valid experimental model for studying MPS; however, a comparison of the similarities and differences of these two conditions has previously not been performed. Herein, we aimed to identify the similarities and differences in the clinical features and biomarkers between DOMS and MPS in order to better define MPS and identify future areas of (DOMS-informed) MPS research.

EVIDENCE ACQUISITION

In order to identify similarities and differences in the clinical manifestation and biomarkers of DOMS and MPS, scoping literature searches were performed using Medline (1965-2019), Embase (1966-2019) and Central (1966-2019) databases. Fifty-three full-text articles were reviewed out of the 2836 articles retrieved in the search.

EVIDENCE SYNTHESIS

A scoping review of the literature demonstrated that DOMS and MPS similarly present as conditions of musculoskeletal pain that are associated with decreased strength and limited range of motion. However, while taut bands and discrete tender spots were described in DOMS, none of the studies reviewed have characterized whether these tender points represent the classic myofascial trigger point phenomenon observed in MPS. Certain systemic circulation biomarkers, including inflammatory cytokines and growth factors, were commonly elevated in MPS and DOMS; further research is needed to determine if other biomarkers that are currently characterized in DOMS are useful to enhance the clinical evaluation of MPS.

CONCLUSIONS

DOMS and MPS share clinical and biomarker similarities suggesting that DOMS may be a useful model for studying MPS.

Exercise-Induced Regulation of Redox Status in Cardiovascular Diseases: The Role of Exercise Training and Detraining

Although low levels of reactive oxygen species (ROS) are beneficial for the organism ensuring normal cell and vascular function, the overproduction of ROS and increased oxidative stress levels play a significant role in the onset and progression of cardiovascular diseases (CVDs). This paper aims at providing a thorough review of the available literature investigating the effects of acute and chronic exercise training and detraining on redox regulation, in the context of CVDs. An acute bout of either cardiovascular or resistance exercise training induces a transient oxidative stress and inflammatory response accompanied by reduced antioxidant capacity and enhanced oxidative damage. There is evidence showing that these responses to exercise are proportional to exercise intensity and inversely related to an individual’s physical conditioning status. However, when chronically performed, both types of exercise amplify the antioxidant defense mechanism, reduce oxidative stress and preserve redox status. On the other hand, detraining results in maladaptations within a time-frame that depends on the exercise training intensity and mode, as high-intensity training is superior to low-intensity and resistance training is superior to cardiovascular training in preserving exercise-induced adaptations during detraining periods. Collectively, these findings suggest that exercise training, either cardiovascular or resistance or even a combination of them, is a promising, safe and efficient tool in the prevention and treatment of CVDs.

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.

Bisphenol A, Tobacco Smoke, and Age as Predictors of Oxidative Stress in Children and Adolescents

OBJECTIVES

The purpose of this study was to investigate bisphenol A (BPA) and its role in the induction of oxidative stress and confirm the same for tobacco smoke.

METHODS

A total of 223 young, healthy students (7-19 years old) were recruited in Chivasso, Italy. A spot of urine of each subject was analyzed to quantify BPA, cotinine, and 15F2t-isoprostane.

RESULTS

BPA showed a slight increase of concentration proportional with increasing age, even though the 11-14 years age group had slightly lower results, inducing a V-shape. The same trend was observed for 15F2t-isoprostane and cotinine. The result of piecewise linear robust regression shows a break point of the effect of BPA on 15F2t-isoprostane at 6 ng/mg CREA (p < 0.001). At higher levels, 15F2t-isoprostane shows an exponential increase by more than threefold for each one-log unit of BPA. An increase of oxidative stress due to BPA was observed, but only from 6 ng/mg of CREA up. Passive tobacco smoke is also able to induce an increase in oxidative stress.

CONCLUSION

Prevention against BPA and passive tobacco smoke represents an important tool for promoting the highest health standard.

Combined exercise training improves blood pressure and antioxidant capacity in elderly individuals with hypertension

Background/objective

Although regular exercise plays a role in achieving healthy aging, a specific mode of exercise may be required for elderly individuals with hypertension (HT). Therefore, this study aimed to assess the effects of combined endurance and strength training (CBT) on blood pressure (BP) and antioxidant capacity in elderly individuals with HT.

Methods

In a single-blinded, randomized controlled trial, 54 older men and women aged 67 ± 5.8 years completed endurance training (ET, n = 13), strength training (ST, n = 13), combined endurance and strength training (CBT, n = 16) or served as controls (CON, n = 12). The intervention was a supervised exercise training (1-h sessions, three per week for 12 weeks), followed by a self-supervised exercise training for 12 weeks. Measurements of BP, glutathione peroxidase (GPx), total nitrite/nitrate (NOx-), malondialdehyde (MDA), and high-sensitive C-reactive protein (hs-CRP) were obtained before and after the supervised and the self-supervised periods.

Results

After the supervised period, systolic BP (SBP) decreased by 7.9% in the ET (p < 0.05) and 8.2% in the CBT (p < 0.01); GPx activity increased by 41.3% in the ET (p < 0.01), 19.1% in the ST (p < 0.05), and 49.2% in the CBT (p < 0.01); NOx-concentrations increased by 66.2% in the ET and 71.9% in the CBT (both p < 0.01), MDA concentrations decreased by 65.1% in the ST (p < 0.05) and 61% in the CBT (p < 0.01); hs-CRP concentrations decreased by 49.2% in only the CBT (p < 0.05). After the self-supervised period, SBP decreases by 7.5% in only the CBT (p < 0.01); NOx-concentrations increased by 68.5% in the ET and 92.4% in the CBT (both p < 0.01). However, there was no significant difference in SBP, GPx activity, NOx-, MDA and hs-CRP concentrations between the training groups.

Conclusion

The hypotensive and antioxidant effects of the CBT seem to be similar to the ET after the supervised training period. However, after the self-supervised training period, the CBT program might affect better due to greater exercise adherence and attendance in elderly individuals with HT.

Effects of resveratrol supplementation in male Wistar rats undergoing an endurance exercise and acute exercise training

OBJECTIVE

The present study was aimed to assess the effect of Resveratrol supplementation, endurance exercise and acute exercise training on oxidative stress and tissue damage markers.

METHODS

Sixty-four male Wistar rats were categorized into four groups including resveratrol group, exercise group, exercise + resveratrol group (n= 16) and control group (n= 16). RES was orally administered to male rats for 28 day at a dose of 10 mg per kg body during exercise. Following the familiarization sessions, rats were acclimated to a calibrated motor driven rodent treadmill for endurance exercise and acute exercise implementation. Changes in oxidative stress and tissue damage markers including 8-hydroxy-2'-deoxyguanosine (8-OhdG), Lactate dehydrogenase (LDH), Creatine Phosphokinase (CPK), protein carbonyl were biochemically measured using commercial ELISA kits based on the manufacturer's instructions.

RESULTS

The endurance and acute exercise training led to an increase in the levels of CPK and LDH, However, following the endurance and acute exercise training, a reduction in the level of carbonyl and 8-OHdG was observed. RES supplementation did not have any effect on the levels of CPK and LDH; nevertheless, reduced significantly carbonyl, and 8-OHdG levels. Based on this evidence, RES may have protective effects against exercise-induced oxidative stress.

CONCLUSION

This study provides further evidence of the antioxidant effects of RES after exercise. However, several factors such as type and duration of exercise, the type of model, the amount of RES supplementation and the time-course consideration can affect the quality of the results. For this reason, further studies in this field are required.

Extracellular matrix roles in cardiorenal fibrosis: Potential therapeutic targets for CVD and CKD in the elderly

Whereas hypertension, diabetes, and dyslipidemia are age-related risk factors for cardiovascular disease (CVD) and chronic kidney disease (CKD), aging alone is an independent risk factor. With advancing age, the heart and kidney gradually but significantly undergo inflammation and subsequent fibrosis, which eventually results in an irreversible decline in organ physiology. Through cardiorenal network interactions, cardiac dysfunction leads to and responds to renal injury, and both facilitate aging effects. Thus, a comprehensive strategy is needed to evaluate the cardiorenal aging network. Common hallmarks shared across systems include extracellular matrix (ECM) accumulation, along with upregulation of matrix metalloproteinases (MMPs) including MMP-9. The wide range of MMP-9 substrates, including ECM components and inflammatory cytokines, implicates MMP-9 in a variety of pathological and age-related processes. In particular, there is strong evidence that inflammatory cell-derived MMP-9 exacerbates cardiorenal aging. This review explores the potential therapeutic targets against CVD and CKD in the elderly, focusing on ECM and MMP roles.

Nuclear Accumulation of HSP70 in Mouse Skeletal Muscles in Response to Heat Stress, Aging, and Unloading With or Without Reloading

The purpose of this study was to investigate the nuclear accumulation of heat shock protein 70 (HSP70), a molecular chaperonin in mouse skeletal muscle in response to aging, heat stress, and hindlimb unloading with or without reloading. Profiles of HSP70-specific nuclear transporter Hikeshi in skeletal muscles were also evaluated. Heat stress-associated nuclear accumulation of HSP70 was observed in slow soleus (SOL) and fast plantaris (PLA) muscles of young (10-week-old) mice. Mean nuclear expression level of HSP70 in slow medial gastrocnemius (MGAS) and PLA muscles of aged (100-week-old) mice increased ~4.8 and ~1.7 times, compared to that of young (10-week-old) mice. Reloading following 2-week hindlimb unloading caused accumulation of HSP70 in myonuclei in MGAS and PLA of young mice ( p < 0.05). However, reloading-associated nuclear accumulation of HSP70 was not observed in both types of muscles of aged mice. On the other hand, 2-week hindlimb unloading had no impact on the nuclear accumulation of HSP70 in both muscles of young and aged mice. Nuclear expression level of Hikeshi in both MGAS and PLA in mice was suppressed by aging. No significant changes in the nuclear Hikeshi in both muscles were induced by unloading with or without reloading. Results of this study indicate that the nuclear accumulation of HSP70 might show a protective response against cellular stresses in skeletal muscle and that the protective response may be suppressed by aging. Protective response to aging might depend on muscle fiber types.

Oxidative Stress is a Convincing Contributor to Idiopathic Chronic Fatigue

The linkage between oxidative stress and idiopathic chronic fatigue (ICF) has not been explored in detail. This study thoroughly compared the serum levels of biomarkers for oxidative stress and antioxidants from 103 subjects with ICF (20 men and 83 women) to those of 82 healthy volunteers (27 men and 55 women). Oxidative parameters, which included reactive oxygen species (ROS), malondialdehyde (MDA) and F2-isoprotan, and tumor necrosis factor-alpha (TNF-α) were significantly elevated, while antioxidant parameters, which included total antioxidant activity (TAC), catalase, superoxide dismutase, SOD and GSH activity, were decreased compared to those of healthy subjects (by approximately 1.2- to 2.3-fold, p < 0.05 or 0.01). Our results confirmed that oxidative stress is a key contributor in the pathophysiology of ICF, and firstly explored the features of oxidative stress parameters in ICF subjects compared to a healthy population.

Association between Physical Exercise and Biomarkers of Oxidative Stress among Middle-Aged and Elderly Community Residents with Essential Hypertension in China

This study aimed to investigate the role of different types and frequencies of physical exercise in biomarkers of oxidative stress among middle-aged and elderly community residents with essential hypertension in China. A community-based cross-sectional survey was undertaken in 7 subdistricts. Individuals, 45-79 years old, with essential hypertension (n = 402) and without cardiovascular disease (n = 1047) were included. Superoxide dismutase (SOD) activities and plasma levels of malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) were determined. Multilevel linear regression was used to estimate the associations between various types of physical exercise and oxidative stress biomarker levels. Participants engaged in high frequency walking/square dancing or taiji/yoga demonstrated decreased systolic blood pressure in both groups; however, diastolic blood pressure decreased only among individuals with hypertension participating in walking/square dancing. In individuals with hypertension, MDA levels decreased in those participating in walking/square dancing, SOD activity increased in those participating in walking/square dancing, and 4-HNE levels decreased in those involved in taiji/yoga. In individuals without cardiovascular disease, MDA levels decreased in those involved in walking/square dancing or taiji/yoga, SOD activity increased in those performing walking/square dancing, and 4-HNE levels decreased in those involved in taiji/yoga. Oxidative stress marker levels also improved in those involved in walking/square dancing or taiji/yoga groups as the exercise frequency increased. Thus, frequent participation in walking/square dancing or taiji/yoga effectively decreases hypertension-related oxidative stress biomarker levels.

Exogenous Plant-Based Nutraceutical Supplementation and Peripheral Cell Mononuclear DNA Damage Following High Intensity Exercise

Plant-based nutraceuticals are categorised as nutritional supplements which contain a high concentration of antioxidants with the intention of minimising the deleterious effect of an oxidative insult. The primary aim of this novel study was to determine the effect of exogenous barley-wheat grass juice (BWJ) on indices of exercise-induced oxidative stress. Ten (n = 10) apparently healthy, recreationally trained (V̇O_2max 55.9 ± 6 mL&middot;kg^&minus;1&middot;min^&minus;1), males (age 22 ± 2 years, height 181 ± 6 cm, weight 87 ± 8 kg, body mass index (BMI) 27 ± 1) volunteered to participant in the study. In a randomised, double-blinded, placebo-controlled crossover design, participants consumed either a placebo, a low dose (70 mL per day) of BWJ, or a high dose (140 mL per day) of BWJ for 7-days. Experimental exercise consisted of a standard maximal oxygen uptake test until volitional fatigue. DNA damage, as assessed by the single cell gel electrophoresis comet assay, increased following high intensity exercise across all groups (time &times; group; p < 0.05, Effect Size (ES) = 0.7), although there was no selective difference for intervention (p > 0.05). There was a main effect for time in lipid hydroperoxide concentration (pooled-group data, pre- vs. post-exercise, p < 0.05, ES = 0.2) demonstrating that exercise increased lipid peroxidation. Superoxide dismutase activity (SOD) increased by 44.7% following BWJ supplementation (pooled group data, pre- vs. post). The ascorbyl free radical (p < 0.05, ES = 0.26), &alpha;-tocopherol (p = 0.007, ES = 0.2), and xanthophyll (p = 0.000, ES = 0.5), increased between the pre- and post-exercise time points indicating a main effect of time. This study illustrates that a 7-day supplementation period of a novel plant-derived nutraceutical product is insufficient at attenuating exercise-induced oxidative damage. It is possible that with a larger sample size, and longer supplementation period, this novel plant-based nutraceutical could potentially offer effective prophylaxis against exercise-induced oxidative stress; as such, this justifies the need for further research.

Antipsychotic-induced disorders: Reported cases and prospective study on muscle biomarkers after high exposure to haloperidol

Antipsychotic drugs are known to induce neuromuscular effects. In this study, we review 13 years (2002-2014) of antipsychotic intoxications reported by the anti-poisoning center of Algiers (APCA). The most recorded symptoms were neuromuscular/muscular disorders, of which haloperidol was the most inducer among all antipsychotics. A prospective study was conducted between December 2012 and January 2017 to evaluate muscle effects generated after intentional or accidental ingestion of haloperidol. Fifty-one patients admitted in different emergency departments in Algiers were included in this study. Urine and blood samples were collected from each patient for biological and toxicological monitoring and a group of healthy volunteers was assessed for comparison purpose. There was no significant difference in plasma lactate dehydrogenase (LDH) activity between healthy volunteers and exposed patients even when high levels of haloperidol were recorded. In contrast, selenium concentration and creatine kinase (CK) activity in plasma samples were significantly higher in patients exposed to high levels of haloperidol compared to healthy volunteers. Large percentage of patients exposed to high levels of haloperidol presented a significant elevated CK activity and high selenium concentration regarding the physiological thresholds. Additionally, CK activity and selenium concentration correlated positively with plasma content of haloperidol suggesting a dose-dependent relationship. In conclusion, some biomarkers (CK and selenium) may reflect muscle adverse effects of high haloperidol exposure that result possibly from muscle rigidity.

Relationship Between Aerobic Capacity With Oxidative Stress and Inflammation Biomarkers in the Blood of Older Mexican Urban-Dwelling Population

The maximal oxygen uptake (VO2max) constitutes an indicator of an organism’s capacity to integrate oxygen into the metabolism to obtaining energy. The aim of this study was to determine the relationship between VO2max and oxidative stress (OxS) and chronic inflammation in the elderly individuals. A cross-sectional and exploratory study was conducted in a sample of 52 older persons. We measured plasma lipid peroxides (LPO), red blood cell glutathione peroxidase, red blood cell superoxide dismutase, and total antioxidant status. The interleukin 10 and tumor necrosis factor-α (TNF-α) were measured in serum by ELISA. The VO2max was determined by the Rockport aerobic test, and the energy expenditure (caloric expenditure and metabolic equivalence unit (MET) per day) was measured by a 3-day activity record. We observed a positive correlation between VO2 max with IL-10, MET/day•day-1 and kcal•day-1 (r = 0.31, P < .05, r = 0.44, P < .01, and r = 0.29, P < .05, respectively), and a negative correlation with the body mass index, TNF-α, and LPO (r = −0.27, P < .05, r = −0.29, P < .05, and r = −0.40, P < .01 respectively). Our findings suggest that there is an inverse relationship between the aerobic capacity and the OxS and chronic inflammation biomarkers in the blood in older Mexican adults.

The effect of Opuntia ficus-indica juice supplementation on oxidative stress, cardiovascular parameters, and biochemical markers following yo-yo Intermittent recovery test

The aim of the study was to investigate the effect of a flavonoid-rich fresh fruit juice on cardiovascular, oxidative stress, and biochemical parameters during the yo-yo intermittent recovery test (YYIRT). Twenty-two healthy males subjects participated in this study divided into two groups: An experimental group (EG: n = 11) who consumed the antioxidant supplement and a control group (CG: n = 11). All participants performed two test sessions at 07:00 hr before and after 2 weeks of supplementation with Opuntia ficus-indica juice. Blood samples were taken before (P1) and immediately (P2) after the YYIRT. Our results showed that following the 2,2-diphenyl-1- picrylhydrazyl (DPPH ●) test, the Opuntia ficus-indica juice has an antioxidant capacity for capturing free radicals (p < .05) and reducing oxidative stress related to exercise. Concerning biochemical and cardiovascular parameters, our results showed a significant increase on total cholesterol (TC) (p < .01), triglycerides (TG) (p < .05), high-density lipoprotein (HDL) (p < .01), low-density lipoprotein (LDL) (p < .01), creatine kinase (CK) (p < .01), lactate deshydrogenase (LDH) (p < .01), glucose (GLC) (p < .01), systolic (SBP), and diastolic blood pressure (DBP) (p < .01) immediately after exercise. However, TC (p < .05), TG (p < .05) and LDL (p < .05), the maximal heart rate (HRmax), the CK (p < .05), and LDH (p < .01) as well as the malondialdehyde (MDA) (p < .01) demonstrated a significant decrease after supplementation of Opuntia ficus-indica juice before and immediately after YYIRT. However, no significant effect on HDL (p > .05), GLC (p > .05) levels nor the SBP and DBP (p > .05) was observed after supplementation with Opuntia ficus-indica juice. The supplementation leads to an improvement on YYIRT performance (The total distance covered during the YYIRT,VO 2max, VMA) and the rating of perceived exertion (RPE). Opuntia ficus-indica juice has a potent antioxidant activity that reduces total and LDL-cholesterol with only a moderate lowering of HDL-cholesterol and oxidative stress. Moreover, supplementation decreases muscle damage caused by the endurance exercise.

The Effect of Moderate- Versus High-Intensity Resistance Training on Systemic Redox State and DNA Damage in Healthy Older Women

This study investigated effects of a 16-week progressive resistance training program (RTP) with elastic bands at two different intensities on systemic redox state, DNA damage, and physical function in healthy older women.

Methods:

Participants were randomly assigned to the high-intensity group (HIGH; n = 39), moderate-intensity group (MOD; n = 31), or control group (CG; n = 23). The exercise groups performed an RTP twice a week with three to four sets of 6 (HIGH) or 15 (MOD) repetitions of six overall body exercises at a perceived exertion rate of 8–9 on the OMNI-Resistance Exercise Scale for use with elastic bands. Thiol redox state was determined by reduced glutathione (GSH), oxidized glutathione (GSSG), and GSSG/GSH in blood mononuclear cells. Degree of DNA damage was assessed by presence of the oxidized DNA base molecule 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-OHdG) in urine. Physical function monitoring was based on the arm curl, chair stand, up and go, and 6-min walk tests.

Results:

The HIGH group showed a significant increase in 8-OHdG (+71.07%, effect size [ES] = 1.12) and a significant decrease in GSH (−10.91, ES = −0.69), while the MOD group showed a significant decrease in 8-OHdG levels (−25.66%, ES = −0.69) with no changes in thiol redox state. GSH levels differed significantly between the HIGH and CG groups posttest. The exercise groups showed significant improvements in physical function with no differences between groups.

Conclusion:

RTP at a moderate rather than high intensity may be a better strategy to reduce DNA damage in healthy older women while also increasing independence.

Isoprostanes as markers for muscle aging in older athletes

Introduction

Production of isoprostanes (IsoPs) is enhanced after acute, intense, and prolonged exercise, in untrained subjects. This effect is greater in older subjects. The present study aims to delineate the profile of acute-exercise-induced IsoPs levels in young and older endurance-trained subjects.

Methods

All included subjects were male, young (n = 6; 29 yrs ± 5.7) or older (n = 6; 63.7 yrs ± 2.3), and competitors. The kinetics of F₂-IsoPs in blood-sera was assessed at rest, for the maximal aerobic exercise power (MAP) corresponding to the cardio-respiratory fitness index and after a 30-min recovery period.

Results

No significant time effect on F₂-IsoPs kinetics was identified in young subjects. However, in older athletes, F₂-IsoPs blood-concentrations at the MAP were higher than at rest, whereas these blood-concentrations did not differ between rest and after the 30-min recovery period.

Conclusion

Because plasma glutathione (GSH) promotes the formation of some F₂-IsoPs, we suggest that the surprising decrease in F₂-IsoPs levels in older subjects would be caused by decreased GSH under major ROS production in older subjects. We argue that the assessment F₂-IsoPs in plasma as biomarkers of the aging process should be challenged by exercise to improve the assessment of the functional response against reactive oxygen species in older subjects.

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Acute exercise promotes an increase in F₂-IsoPs plasma level in older athletes.

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The F₂-IsoPs plasma level significantly decreased after recovery in older athletes.

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This kinetic of F₂-IsoPs could reflect a decrease of glutathione (GSH).

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Oxidative stress status determination should be challenged by exercise.

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Assessment of F₂-IsoPs plasma level should be paired to GSH assessment.

The Effects of Physical Training are Varied and Occur in an Exercise Type-Dependent Manner in Elderly Men

Regular exercise can decrease the deleterious effects of aging and limit the development and progression of chronic disease in elderly people, depending on the type, intensity, frequency, and duration of exercise. This study aimed to investigate the potential protective effects of different physical training programs on oxidative stress parameters and inflammatory and neurotrophic mediators in the serum of elderly men. Healthy male volunteers [60 to 80 years; n=55] were divided into four groups: control [Ctr, n=14], aerobic training on dry land [ATdl, n=12]; and combined training on dry land [CTdl, n=12] or in water [CTw, n=17]. The training protocols were performed over 8 weeks, three times per week. Each 1 h session included 5 min warming-up exercise, 50 min specific training [aerobic, strength, or combined], and 5 min stretching. Blood samples were drawn 72 h before [baseline] the beginning of the 8 weeks’ protocol and 48 h after the last training session, processed, and the serum was aliquoted and stored at -70 °C until biochemical assessment of oxidative damage, antioxidant system and neurotrophic, growth and inflammatory factors. Elevated BDNF or IGF-1 levels were observed in the ATdl or CTdl groups, respectively. Overall oxidative stress parameters were improved including reduced lipid oxidative damage and increased thioredoxin reductase and glutathione peroxidase activities and total glutathione. Significant decreases in the inflammatory mediators IL-6 and IL-8 were observed; IL-6 was more susceptible to the effects of type of physical training. Thus, the effects of training in elderly men vary in an exercise type-dependent manner.

A high-caloric diet rich in soy oil alleviates oxidative damage of skeletal muscles induced by dexamethasone in chickens

Objective: Glucocorticoids (GCs) can induce oxidative damage in skeletal muscles. The purpose of this study was to demonstrate a high caloric (HC) diet rich in soy oil would change the oxidative stress induced by a GC.

Methods: The effect of dexamethasone (DEX) and HC diet on oxidative stress in plasma, skeletal muscles (M. pectoralis major, PM; M. biceps femoris, BF), and mitochondria were determined. The biomarkers of oxidative damage and antioxidative enzyme activity were determined. The fatty acid profile of muscles and the activities of complex I and II in mitochondria were measured.

Results: The results showed that DEX increased the concentrations of oxidative damage markers in plasma, muscles, and mitochondria. The activity of complex I was significantly suppressed by DEX. DEX-chickens had higher proportions of polyunsaturated fatty acids and lower proportions of monounsaturated fatty acids in the PM. A HC diet decreased the levels of oxidative damage biomarkers in plasma, muscles, and mitochondria. The interaction between DEX and diet suppressed the activities of complex I and II in HC-chickens.

Discussion: Oxidative damage in skeletal muscles and mitochondria was the result of GC-induced suppression of the activity of mitochondrial complex I. A HC diet improved the antioxidative capacity and reduced the oxidative damage induced by the GC.

Effect of maximal-intensity exercise on systemic nitro-oxidative stress in men and women

OBJECTIVES

The aim of this study was to test the hypotheses: (1) there is a negative correlation between protein and lipid oxidative damage following maximal-intensity exercise, and oxygen uptake and work intensity (%VO2max) at the respiratory compensation point (RCP) in women and men; (2) nitro-oxidative stress following maximal-intensity exercise results from the intensification of anaerobic processes and muscle fibre micro-damage.

METHODS

Study participants comprised 20 women (21.34±1.57 years) and 20 men (21.97±1.41 years) who performed a treadmill incremental test (IT); VO2max: 45.08 ± 0.91 and 57.38 ± 1.22 mL kg-1 min-1 for women and men, respectively. The oxidized low-density lipoprotein (ox-LDL), 3-nitrotyrosine (3-NT) concentration and creatine kinase (CK) as well as lactate dehydrogenase (LDH) activity were measured in the blood serum, and total antioxidative capacity (TAC) and lactate concentration (Lac) were determined in blood plasma before and after IT.

RESULTS

After the IT, increases in ox-LDL, 3-NT, CK, and LDH were seen in both groups (P < 0.05). After the IT, an increase in the TAC was only observed in women (P < 0.05). The post-exercise-induced increase in Lac was significantly higher in men than in women. Only in the group of women was a positive correlation (P < 0.05) between the post-exercise increase in TAC and changes in CK activity and LDH found.

CONCLUSIONS

The gain of ox-LDL and 3-NT following maximal-intensity exercise is independent of VO2max, oxygen consumption and exercise intensity at RCP. This increase of ox-LDL and 3-NT is indicative of similar lipid and protein damage in women and men. A significant increase in TAC in women following maximal-intensity exercise is the result of muscle fibre micro-injuries.

Effects of time-of-day on oxidative stress, cardiovascular parameters, biochemical markers, and hormonal response following level-1 Yo-Yo intermittent recovery test

The aim of this study was to investigate the effect of time-of-day on oxidative stress, cardiovascular parameters, muscle damage parameters, and hormonal responses following the level-1 Yo-Yo intermittent recovery test (YYIRT). A total of 11 healthy subjects performed an intermittent test (YYIRT) at two times-of-day (i.e., 07:00 h and 17:00 h), with a recovery period of ≥36 h in-between, in a randomized order. Blood samples were taken at the rest (baseline) and immediately (post-YYIRT) after the YYIRT for measuring oxidative stress, biochemical markers, and hormonal response. Data were statistically analyzed using one-way and two-way repeated measures ANOVA and Bonferroni test at p < 0.05. Observed power (α = 0.05) and partial eta-squared were used. Our results showed that oxygen uptake (VO2max), maximal aerobic speed, and the total distance covered tended to be higher in the evening (17:00 h). There was also a main effect of time-of-day for cortisol and testosterone concentration, which were higher after the YYIRT in the morning (p < 0.05). The heart rate peak and the rating of perceived exertion scales were lower in the morning (p < 0.05). However, the plasma glucose (p < 0.01), malondialdehyde, creatine kinase (p < 0.01), lactate dehydrogenase (p < 0.05), high-density lipoprotein (p < 0.01), total cholesterol (p < 0.01), and triglycerides (p < 0.05) were higher after the YYIRT in the evening. Low-density lipoprotein, systolic blood pressure, diastolic blood pressure, and lactate levels (p > 0.05) were similar for the morning and evening test. In conclusion, our findings suggest that aerobic performance presents diurnal variation with great result observed in the evening accompanied by an improvement of hormonal, metabolic, and oxidative responses. These data may help to guide athletes and coaches and contribute to public health recommendations on exercise and muscle damage particularly in the competitive periods.

Plasma Actin, Gelsolin and Orosomucoid Levels after Eccentric Exercise

The present study investigated the acute effect of eccentric exercise on blood plasma actin, gelsolin (GSN) and orosomucoid (AGP) levels in untrained and moderately trained individuals, and their correlation with exercise induced muscle damage (EIMD) markers (CK, intensity of muscle soreness and maximal voluntary contraction torque deficit). Healthy physical education students (6 untrained, 12 moderately trained) participated in this research. Actin, GSN, AGP and CK levels were measured in blood plasma at baseline, immediately, 1 h, 6 h and 24 h post-exercise comprising 90 eccentric quadriceps contractions performed on a dynamometer. There was significant time main effect for GSN, AGP, CK and significant difference was found between baseline and the lowest value of post-exercise GSN (p < 0.05), as well as baseline and the highest value of post-exercise AGP (p < 0.05). Relationships were found between GSN levels and other indirect EIMD markers (between all GSN levels at post-exercise and CK activity at 6 h, p < 0.05; GSNMIN and muscle soreness at post-exercise, p < 0.04), GSN and AGP; however, actin did not correlate at any time points with GSN. Actin, GSN, AGP and CK responses after eccentric exercise do not seem sensitive to training status. The plasma actin level is used as an indicator of injury, however, our results suggest that it is not an accurate marker of EIMD, while plasma GSN concentrations show a better relationship with EIMD and the post-exercise inflammatory process. The elevated plasma AGP and the correlation between GSN and AGP seem to be promising for assessment of exercise-induced muscle injury.

Influence of Estimated Training Status on Anti and Pro-Oxidant Activity, Nitrite Concentration, and Blood Pressure in Middle-Aged and Older Women

The purpose of this study was to compare the association between anti and pro-oxidant activity, nitrite concentration, and blood pressure (BP) in middle-aged and older women with different levels of estimated training status (TS). The sample consisted of 155 females (50-84 years) who were submitted to a physical examination to evaluate estimated TS through the "Functional Fitness Battery Test," BP measurements, and plasma blood samples to evaluate pro-oxidant and antioxidant activity and nitrite concentrations. Participants were separated by age into a middle-aged group (<65 years) and an older (≥65 years) group and then subdivided in each group according to TS. Blood biochemistry was similar between groups. On the other hand, protein oxidation was lower in participants with higher TS, independent of age. Older females with higher TS presented higher nitrite concentrations, lower lipoperoxidation, and lower values of BP compared with those with lower TS. Lower GPx activity was observed in participants with higher TS compared with middle-aged with lower TS. Thus, our results suggest that good levels of TS may be associated with lower oxidative stress and higher nitrite concentration and may contribute to maintain normal or reduced blood pressure values.

Proteomic Assessment of the Relevant Factors Affecting Pork Meat Quality Associated with Longissimus dorsi Muscles in Duroc Pigs

Meat quality is a complex trait influenced by many factors, including genetics, nutrition, feeding environment, animal handling, and their interactions. To elucidate relevant factors affecting pork quality associated with oxidative stress and muscle development, we analyzed protein expression in high quality longissimus dorsi muscles (HQLD) and low quality longissimus dorsi muscles (LQLD) from Duroc pigs by liquid chromatographytandem mass spectrometry (LC-MS/MS)-based proteomic analysis. Between HQLD (n = 20) and LQLD (n = 20) Duroc pigs, 24 differentially expressed proteins were identified by LC-MS/MS. A total of 10 and 14 proteins were highly expressed in HQLD and LQLD, respectively. The 24 proteins have putative functions in the following seven categories: catalytic activity (31%), ATPase activity (19%), oxidoreductase activity (13%), cytoskeletal protein binding (13%), actin binding (12%), calcium ion binding (6%), and structural constituent of muscle (6%). Silver-stained image analysis revealed significant differential expression of lactate dehydrogenase A (LDHA) between HQLD and LQLD Duroc pigs. LDHA was subjected to in vitro study of myogenesis under oxidative stress conditions and LDH activity assay to verification its role in oxidative stress. No significant difference of mRNA expression level of LDHA was found between normal and oxidative stress condition. However, LDH activity was significantly higher under oxidative stress condition than at normal condition using in vitro model of myogenesis. The highly expressed LDHA was positively correlated with LQLD. Moreover, LDHA activity increased by oxidative stress was reduced by antioxidant resveratrol. This paper emphasizes the importance of differential expression patterns of proteins and their interaction for the development of meat quality traits. Our proteome data provides valuable information on important factors which might aid in the regulation of muscle development and the improvement of meat quality in longissimus dorsi muscles of Duroc pigs under oxidative stress conditions.

A lifelong competitive training practice attenuates age-related lipid peroxidation

The effect of exercise-induced oxidative stress on health and aging is not clearly explained. This study examined the effects of habitual sport practice, age, and submaximal exercise on the blood markers of oxidative stress, muscle damage, and antioxidant response. Seventy-two healthy men were grouped by their habitual sport practice: inactive (<1.5 h/week), recreational (3-8 h/week), and trained athletes (>8 h/week), and further divided by age: young (18-25 years), adult (40-55 years), and senior (>55 years). Blood samples were collected at rest and after submaximal effort. Hydroperoxides and superoxide dismutase, glutathione peroxidase, and catalase activities were measured by spectrophotometry. Nuclear DNA damage was analyzed by comet assay. The alpha-actin release was analyzed by Western blot. Alpha-tocopherol, retinol, and coenzyme-Q10 were quantified by high-performance liquid chromatography analysis. Data was analyzed through a factorial ANOVA and the Bonferroni post hoc test. Lipid peroxidation increased significantly with age and submaximal effort (p < 0.05). However, the trained athlete group presented lower lipid peroxidation compared with the recreational group (MD = 2.079, SED = 0.58, p = 0.002) and inactive group (MD = 1.979, SED = 0.61, p = 0.005). Trained athletes showed significant higher alpha-actin levels (p < 0.001) than the other groups. Recreational group showed lower nuclear DNA damage than trained athletes (MD = 3.681, SED = 1.28, p = 0.015). Nevertheless, the inactive group presented significantly higher superoxide dismutase and catalase (p < 0.05) than the other groups. Data suggested that habitual competitive training practice could prevent age-related increases of plasma lipid peroxidation, which, according with our results, cannot be entirely attributed to blood antioxidant defense systems.

Acute Oxidative Effect and Muscle Damage after a Maximum 4 Min Test in High Performance Athletes

The purpose of this investigation was to determine lipid peroxidation markers, physiological stress and muscle damage in elite kayakers in response to a maximum 4-min kayak ergometer test (KE test), and possible correlations with individual 1000m kayaking performances. The sample consisted of twenty-three adult male and nine adult female elite kayakers, with more than three years’ experience in international events, who voluntarily took part in this study. The subjects performed a 10-min warm-up, followed by a 2-min passive interval, before starting the test itself, which consisted of a maximum 4-min work paddling on an ergometer; right after the end of the test, an 8 ml blood sample was collected for analysis. 72 hours after the test, all athletes took part in an official race, when then it was possible to check their performance in the on site K1 1000m test (P1000m). The results showed that all lipoproteins and hematological parameters tested presented a significant difference (p≤0.05) after exercise for both genders. In addition, parameters related to muscle damage such as lactate dehydrogenase (LDH) and creatine kinase (CK) presented significant differences after stress. Uric acid presented an inverse correlation with the performance (r = -0.76), while CK presented a positive correlation (r = 0.46) with it. Based on these results, it was possible to verify muscle damage and the level of oxidative stress caused by indoor training with specific ergometers for speed kayaking, highlighting the importance of analyzing and getting to know the physiological responses to this type of training, in order to provide information to coaches and optimize athletic performance.

Effects of Methane-Rich Saline on the Capability of One-Time Exhaustive Exercise in Male SD Rats

Purpose

To explore the effects of methane-rich saline (CH₄ saline) on the capability of one-time exhaustive exercise in male SD rats.

Methods

Thirty rats were equally divided into to three groups at random: control group (C), placebo group (P) and methane saline group (M). Rats in M group underwent intraperitoneal injection of CH₄ saline, and the other two groups simultaneously underwent intraperitoneal injection of normal saline. Then, the exercise capability of rats was tested through one-time exhaustive treadmill exercise except C group. Exercise time and body weight were recorded before and after one-time exhaustive exercise. After exhaustive exercise, the blood and gastrocnemius samples were collected from all rats to detect biochemical parameters in different methods.

Results

It was found that the treadmill running time was significantly longer in rats treated with CH₄ saline. At the same time, CH₄ saline reduced the elevation of LD and UN in blood caused by one-time exhaustive exercise. The low level of blood glucose induced by exhaustive exercise was also normalized by CH₄ saline. Also CH₄ saline lowered the level of CK in plasma. Furthermore, this research indicated that CH₄ saline markedly increased the volume of T-AOC in plasma and alleviated the peak of TNF-α in both plasma and gastrocnemius. From H&E staining, CH₄ saline effectively improved exercise-induced structural damage in gastrocnemius.

Conclusions

CH₄ saline could enhance exercise capacity in male SD rats through increase of glucose aerobic oxidation, improvement of metabolic clearance and decrease of exhaustive exercise-induced gastrocnemius injury.

Wet, volatile, and dry biomarkers of exercise-induced muscle fatigue

Background

The physiological background of exercise-induced muscle fatigue(EIMUF) is only poorly understood. Thus, monitoring of EIMUF by a single or multiple biomarkers(BMs) is under debate.

After a systematic literature review 91 papers were included.

Results

EIMUF is mainly due to depletion of substrates, increased oxidative stress, muscle membrane depolarisation following potassium depletion, muscle hyperthermia, muscle damage, impaired oxygen supply to the muscle, activation of an inflammatory response, or impaired calcium-handling. Dehydration, hyperammonemia, mitochondrial biogenesis, and genetic responses are also discussed. Since EIMUF is dependent on age, sex, degree of fatigue, type, intensity, and duration of exercise, energy supply during exercise, climate, training status (physical fitness), and health status, BMs currently available for monitoring EIMUF have limited reliability. Generally, wet, volatile, and dry BMs are differentiated. Among dry BMs of EIMUF the most promising include power output measures, electrophysiological measures, cardiologic measures, and questionnaires. Among wet BMs of EIMUF those most applicable include markers of ATP-metabolism, of oxidative stress, muscle damage, and inflammation. VO₂-kinetics are used as a volatile BM.

Conclusions

Though the physiology of EIMUF remains to be fully elucidated, some promising BMs have been recently introduced, which together with other BMs, could be useful in monitoring EIMUF. The combination of biomarkers seems to be more efficient than a single biomarker to monitor EIMUF. However, it is essential that efficacy, reliability, and applicability of each BM candidate is validated in appropriate studies.