Aerobic and strength training induce changes in oxidative stress parameters and elicit modifications of various cellular components in skeletal muscle of aged rats

Inflammatory and Oxidative Patterns Regulated by Theracurmin Intake in an Experimental Model of Hypertrophic Training and Detraining

Dietary supplements have improved performance and muscle hypertrophy in athletes and nonathletes in the past few decades. Theracurmin, a nutraceutical supplement based on curcumin, has been highlighted by its anti-inflammatory and antioxidant properties in physiological and pathological conditions. This study aimed to investigate the effects of theracurmin intake (300 mg/kg), containing 30 mg/kg of curcumin, in male Swiss mice (n = 66) under distinct protocols of climbing stairs (strength exercise) and their respective detraining period. Animals, aged 7-9 weeks, were trained for 8 weeks (5 days/week), with a minimum interval of 24 hr between each session, followed by a 4-week detraining period. After euthanasia, skeletal muscle hypertrophy was evaluated through histological analysis. Tissue inflammatory release of tumor necrosis factor, interleukin (IL)-6, IL-10, and chemokine C-C motif ligand 2, as well as the activity of oxidative stress enzymes (catalase, superoxide dismutase, and lipid peroxidation), were also assessed. In trained animals, inflammatory mediators and skeletal muscle mass increased after training (p = .0004). Theracurmin did not revert the muscle hypertrophy, but it decreased tissue chemokine C-C motif ligand 2 (p = .0001) and lipid peroxidation (p < .0001) after strength training and after detraining (p = .0008 and p = .001, respectively). Tissue tumor necrosis factor was only reduced during the detraining period (p = .037), whereas IL-6 (p = .0001) and IL-10 (p < .0001) increased after the training protocol. No differences were observed in catalase and superoxide dismutase. Our data suggest that theracurmin intake contributes to the reduction of tissue inflammatory mediators during strength training and/or detraining without essential activity on skeletal muscle hypertrophy.

Protective effects of different exercise modalities on oxidative stress in animal models of high intraocular pressure and diabetes

High intraocular pressure (HIOP) and high glucose levels are associated with oxidative stress. Although physical exercise protects against oxidative damage, its specific impact on eye health remains unclear. Thus, this study aimed to assess the impact of physical exercise on the oxidative status of whole eyes in male Swiss mice subjected to HIOP model and cafeteria diet (CD). In experiment one, mice were divided into sedentary, aerobic, and strength (four-week physical exercise) groups and subjected to an HIOP/ischemia model. In experiment two, mice were submitted to CD and voluntary physical exercise for 18 weeks, according to the following groups: sedentary control, sedentary CD, exercise control, and exercise CD. Experiment one revealed elevated 2',7'-dichlorodihydrofluorescein (DCFH) levels in aerobic group, which decreased in all groups after ischemia. Nitrite levels were decreased on strength than in sedentary group. The superoxide dismutase (SOD) activity did not change in all treatments. Although catalase (CAT) activity increased in aerobic and strength groups, and after ischemia in all groups. In experiment two, the sedentary CD group presented higher body weight than the other groups. DCFH levels were increased in the exercise control and reduced in the exercise CD compared with the other groups. CAT activity and sulfhydryl groups were decreased, while protein carbonylation was increased in the sedentary CD group compared with the other groups. Thus, these results suggested that physical exercise promoted antioxidant effects on eyes exposed to an HIOP model and CD.

BMAL1/PGC1α4-FNDC5/irisin axis impacts distinct outcomes of time-of-day resistance exercise

BACKGROUND

Resistance exercise leads to improved muscle function and metabolic homeostasis. Yet how circadian rhythm impacts exercise outcomes and its molecular transduction remains elusive.

METHODS

Human volunteers were subjected to 4 weeks of resistance training protocols at different times of day to assess training outcomes and their associations with myokine irisin. Based on rhythmicity of Fibronectin type III domain containing 5 (FNDC5/irisin), we trained wild type and FNDC5 knockout mice at late active phase (high FNDC5/irisin level) or late rest phase (low FNDC5/irisin level) to analyze exercise benefits on muscle function and metabolic homeostasis. Molecular analysis was performed to understand the regulatory mechanisms of FNDC5 rhythmicity and downstream signaling transduction in skeletal muscle.

RESULTS

In this study, we showed that regular resistance exercises performed at different times of day resulted in distinct training outcomes in humans, including exercise benefits and altered plasma metabolomics. We found that muscle FNDC5/irisin levels exhibit rhythmicity. Consistent with human data, compared to late rest phase (low irisin level), mice trained chronically at late active phase (high irisin level) gained more muscle capacity along with improved metabolic fitness and metabolomics/lipidomics profiles under a high-fat diet, whereas these differences were lost in FNDC5 knockout mice. Mechanistically, Basic helix-loop-helix ARNT like 1 (BMAL1) and Peroxisome proliferative activated receptor, gamma, coactivator 1 alpha 4 (PGC1α4) induce FNDC5/irisin transcription and rhythmicity, and the signaling is transduced via αV integrin in muscle.

CONCLUSION

Together, our results offered novel insights that exercise performed at distinct times of day determines training outcomes and metabolic benefits through the rhythmic regulation of the BMAL1/PGC1α4-FNDC5/irisin axis.

Protective effects of early exercise on neuroinflammation, and neurotoxicity associated by traumatic brain injury: a behavioral and neurochemical approach

OBJECTIVE

The benefits of exercise in TBI have been proven. However, the time-dependent effects of exercise initiation and the involved mechanisms are controversial. We investigated the effects of preconditioning, continuous, early, and delayed treadmill exercise on motor behavior, brain edema, inflammation, and oxidative stress in experimental traumatic brain injury (TBI).

MATERIALS AND METHODS

48 male rats were assigned into two groups: sedentary control (Sham and TBI) and exercise groups: 1MB (preconditioning, initiation beginning at 1 month before trauma), 1MBA (continuous, initiation beginning at 1 month before and continuing 1 month after trauma), 24hA (early, initiation beginning at 24 h after trauma), and 1WA (delay, initiation beginning at 1 week after trauma). The rats in exercise groups were forced to run on a treadmill five days a week for 30 min per day. Rotarod and open file were used to assess motor behavior. ELISA was also used to measure total antioxidant capacity (TAC), tumor necrosis factor-alpha (TNF-α), and malondialdehyde (MDA) in serum and CSF.

RESULTS

Exercise significantly decreased neurological impairments, motor deficits, and apoptosis compared with the sedentary group. Early (within 24 h) and ongoing (1 MBA) exercise significantly improved motor behavior after TBI. In addition, these exercise programs inhibited brain edema and the number of apoptotic cells. MDA and TNF-α levels increased in all exercise groups, but the effects were greater after early exercise than after delayed exercise, resulting in a significant decrease in TAC levels in serum and CSF. We discovered a positive correlation between MDA, TAC, and TNF-α concentration in serum and CSF.

CONCLUSION

Our finding suggests that early exercise (24hA) and 1MBA groups afford neuroprotection and reduce the second injury consequence, probably by reducing neuronal apoptosis and oxidative stress.

Exercise training and changes in skeletal muscle mitochondrial proteins: from blots to "omics"

Mitochondria are essential, membrane-enclosed organelles that consist of ∼1100 different proteins, which allow for many diverse functions critical to maintaining metabolism. Highly metabolic tissues, such as skeletal muscle, have a high mitochondrial content that increases with exercise training. The classic western blot technique has revealed training-induced increases in the relatively small number of individual mitochondrial proteins studied (∼5% of the >1100 proteins in MitoCarta), with some of these changes dependent on the training stimulus. Proteomic approaches have identified hundreds of additional mitochondrial proteins that respond to exercise training. There is, however, surprisingly little crossover in the mitochondrial proteins identified in the published human training studies. This suggests that to better understand the link between training-induced changes in mitochondrial proteins and metabolism, future studies need to move beyond maximizing protein detection to adopting methods that will increase the reliability of the changes in protein abundance observed.

Non-Pharmacological Strategies for Managing Sarcopenia in Chronic Diseases

This article focuses on a range of non-pharmacological strategies for managing sarcopenia in chronic diseases, including exercise, dietary supplements, traditional Chinese exercise, intestinal microecology, and rehabilitation therapies for individuals with limited limb movement. By analyzing multiple studies, the article aims to summarize the available evidence to manage sarcopenia in individuals with chronic diseases. The results strongly emphasize the role of resistance training in addressing chronic diseases and secondary sarcopenia. Maintaining the appropriate frequency and intensity of resistance training can help prevent muscle atrophy and effectively reduce inflammation. Although aerobic exercise has limited ability to improve skeletal muscle mass, it does have some positive effects on physical function. Building upon this, the article explores the potential benefits of combined training approaches, highlighting their helpfulness for overall quality of life. Additionally, the article also highlights the importance of dietary supplements in combating muscle atrophy in chronic diseases. It focuses on the importance of protein intake, supplements rich in essential amino acids and omega-3, as well as sufficient vitamin D to prevent muscle atrophy. Combining exercise with dietary supplements appears to be an effective strategy for preventing sarcopenia, although the optimal dosage and type of supplement remain unclear. Furthermore, the article explores the potential benefits of intestinal microecology in sarcopenia. Probiotics, prebiotics, and bacterial products are suggested as new treatment options for sarcopenia. Additionally, emerging therapies such as whole body vibration training, blood flow restriction, and electrical stimulation show promise in treating sarcopenia with limited limb movement. Overall, this article provides valuable insights into non-pharmacological strategies for managing sarcopenia in individuals with chronic diseases. It emphasizes the importance of a holistic and integrated approach that incorporates exercise, nutrition, and multidisciplinary interventions, which have the potential to promote health in the elderly population. Future research should prioritize high-quality randomized controlled trials and utilize wearable devices, smartphone applications, and other advanced surveillance methods to investigate the most effective intervention strategies for sarcopenia associated with different chronic diseases.

Advances in exercise to alleviate sarcopenia in older adults by improving mitochondrial dysfunction

Sarcopenia is a chronic degenerative disease affecting primarily older adults. A growing aging population is gradually increasing the number of patients suffering from sarcopenia, placing increasing financial pressure on patients' families and society in general. There is a strong link between mitochondrial dysfunction and sarcopenia pathogenesis. As a result, treating sarcopenia by improving mitochondrial dysfunction is an effective strategy. Numerous studies have demonstrated that exercise has a positive effect on mitochondrial dysfunction when treating sarcopenia. Exercise promotes mitochondrial biogenesis and mitochondrial fusion/division to add new mitochondria or improve dysfunctional mitochondria while maintaining mitochondrial calcium homeostasis, mitochondrial antioxidant defense system, and mitochondrial autophagy to promote normal mitochondrial function. Furthermore, exercise can reduce mitochondrial damage caused by aging by inhibiting mitochondrial oxidative stress, mitochondrial DNA damage, and mitochondrial apoptosis. Exercise effectiveness depends on several factors, including exercise duration, exercise intensity, and exercise form. Therefore, Moderate-intensity exercise over 4 weeks potentially mitigates sarcopenia in older adults by ameliorating mitochondrial dysfunction. HIIT has demonstrated potential as a viable approach to addressing sarcopenia in aged rats. However, further investigation is required to validate its efficacy in treating sarcopenia in older adults.

Exercise and mitochondrial mechanisms in patients with sarcopenia

Sarcopenia is a severe loss of muscle mass and functional decline during aging that can lead to reduced quality of life, limited patient independence, and increased risk of falls. The causes of sarcopenia include inactivity, oxidant production, reduction of antioxidant defense, disruption of mitochondrial activity, disruption of mitophagy, and change in mitochondrial biogenesis. There is evidence that mitochondrial dysfunction is an important cause of sarcopenia. Oxidative stress and reduction of antioxidant defenses in mitochondria form a vicious cycle that leads to the intensification of mitochondrial separation, suppression of mitochondrial fusion/fission, inhibition of electron transport chain, reduction of ATP production, an increase of mitochondrial DNA damage, and mitochondrial biogenesis disorder. On the other hand, exercise adds to the healthy mitochondrial network by increasing markers of mitochondrial fusion and fission, and transforms defective mitochondria into efficient mitochondria. Sarcopenia also leads to a decrease in mitochondrial dynamics, mitophagy markers, and mitochondrial network efficiency by increasing the level of ROS and apoptosis. In contrast, exercise increases mitochondrial biogenesis by activating genes affected by PGC1-ɑ (such as CaMK, AMPK, MAPKs) and altering cellular calcium, ATP-AMP ratio, and cellular stress. Activation of PGC1-ɑ also regulates transcription factors (such as TFAM, MEFs, and NRFs) and leads to the formation of new mitochondrial networks. Hence, moderate-intensity exercise can be used as a non-invasive treatment for sarcopenia by activating pathways that regulate the mitochondrial network in skeletal muscle.

The effect of resistance training on serum levels of sex hormones and sperm quality in male rats under X-ray radiation

OBJECTIVES

The present study aims to investigate the effects of resistance training on sex hormones and sperm parameters in male rats under X-ray.

METHODS

In this experimental study, 24 Sprague Dawley rats (200-250 g) were randomly assigned into four groups: healthy control, irradiated control, healthy training and irradiated training. Irradiation was induced at a dose of 4 Gy on the whole body. The resistance training protocol was performed for 10 weeks. Finally, blood serum was used to assess FSH, LH and testosterone and sperm quality. Data were analyzed using ANOVA and Tukey's post hoc test.

RESULTS

The results showed that radiation significantly reduced serum levels of LH (p=0.42), FSH (p=0.001) and testosterone (p=0.28) between radiation control and healthy control groups. Also, no significant difference was observed between serum levels of LH (p=0.135) and testosterone (p=0.419) in radiation resistance training and the healthy control groups. In addition, significant differences were observed between radiation resistance training and radiation control groups in sperm parameters such as sperm count (p=0.02) and progressively motile sperm (p=0.031).

CONCLUSIONS

It seems that short-term resistance training can improve sperm parameters, including sperm count and sperm motility through increasing serum levels testosterone and LH in male rat under X-ray.

Regulation of mitochondrial dynamic equilibrium by physical exercise in sarcopenia: A systematic review

Background

Sarcopenia is a hallmark of the ageing process, which is characterized by the decline in muscle mass and strength. Growing evidence indicates that mitochondria dysfunction play core roles in this process. Meanwhile, physical exercise is regarded as one of the efficiency therapies to attenuate sarcopenia via regulating mitochondrial function during ageing. However, the specific mechanisms among exercise, mitochondrial function and sarcopenia are still unclear. The aim of this systematic review is to delineate the effects of physical exercise on mitochondria during ageing in order to explore potential target for rescuing sarcopenia.

Methods

A systematic literature search was performed in PubMed, Embase and Web of Science. Information was extracted from the included studies for review.

Results

In this review, 16 pre-clinical studies were included and 105 clinical studies that were not mechanistic research were excluded. 16 pre-clinical studies provided evidence that physical exercise could affect mitochondrial quality control to attenuate sarcopenia. Most of the included studies described the important role of mitochondrial dynamic equilibrium in sarcopenia and showed that effective physical exercise could influence mitochondrial biogenesis, fusion, fission and mitophagy to attenuate sarcopenia in aged animal.

Conclusions

This systematic review provides an up-to-date sequential overview and highlights the link in the potential mitochondria-related target and physical exercise in aged animal.

Translation of this article

Currently, there is no standard treatment method for sarcopenia. This systematic review revealed the underlying mechanisms for how physical exercise improved muscle performance via regulating mitochondrial dynamic equilibrium, which could provide scientific support for using exercise as a timely intervention for sarcopenia. Additionally, this systematic review allows a better understanding of mitochondrial dynamic equilibrium and exercise for future development of new therapeutic interventions to attenuate sarcopenia.

Resistance Exercise Training Improves Metabolic and Inflammatory Control in Adipose and Muscle Tissues in Mice Fed a High-Fat Diet

This study investigates whether ladder climbing (LC), as a model of resistance exercise, can reverse whole-body and skeletal muscle deleterious metabolic and inflammatory effects of high-fat (HF) diet-induced obesity in mice. To accomplish this, Swiss mice were fed for 17 weeks either standard chow (SC) or an HF diet and then randomly assigned to remain sedentary or to undergo 8 weeks of LC training with progressive increases in resistance weight. Prior to beginning the exercise intervention, HF-fed animals displayed a 47% increase in body weight (BW) and impaired ability to clear blood glucose during an insulin tolerance test (ITT) when compared to SC animals. However, 8 weeks of LC significantly reduced BW, adipocyte size, as well as glycemia under fasting and during the ITT in HF-fed rats. LC also increased the phosphorylation of Akt_Ser473 and AMPK_Thr172 and reduced tumor necrosis factor-alpha (TNF-α) and interleukin 1 beta (IL1-β) contents in the quadriceps muscles of HF-fed mice. Additionally, LC reduced the gene expression of inflammatory markers and attenuated HF-diet-induced NADPH oxidase subunit gp91phox in skeletal muscles. LC training was effective in reducing adiposity and the content of inflammatory mediators in skeletal muscle and improved whole-body glycemic control in mice fed an HF diet.

Bee honey and exercise for improving physical performance, reducing fatigue, and promoting an active lifestyle during COVID-19

Active lifestyle has enormous health benefits. However, physical activity has globally decreased since the beginning of the current coronavirus disease 2019 (COVID-19) outbreak because of social distancing measures. Older adults and people with age-related diseases (e.g., diabetes, obesity, cancer, cardiovascular disorders, etc.) are widely affected by COVID-19 and its grave adverse effects because of their baseline poor immune function. Although they are in intense need for the therapeutic benefits of exercise, they may express a low capacity for exercising due to skeletal muscle dysfunction and low motivation. Honey is a natural energy-rich, low glycemic index food with a variety of biological activities. It is reported to correct muscle pathology in diseased conditions. Because skeletal muscle is the key structure involved in exercise, we explored the literature for the exercise-promoting potential of natural honey. Bee honey improves physical performance at moderate levels of activity, and it reduces the production of inflammatory cytokines and biomarkers of fatigue following strenuous exercise among athletes. Supplementing ischemic heart disease patients with honey combined with floral pollen improved patients' tolerance for physical loads and corrected metabolism. Therefore, the therapeutic use of honey may have implications for to increasing the capacity for exercise in aged and diseased individuals. Soundly designed studies are needed to evaluate such possibility.

Strength training or green tea prevent memory deficits in a β-amyloid peptide-mediated Alzheimer's disease model

Antioxidant supplementation and physical exercise have been discussed as strategies to minimize neurodegeneration in Alzheimer's disease (AD). We investigated the neuroprotective effects of strength exercise (StrEx) and green tea (GT) supplementation, combined or not, on memory impairments induced by β-amyloid characterizing an AD-like condition in rats. Wistar rats were submitted to 8 weeks of StrEx, GT supplementation, or StrEx and GT combined. AD-like condition was induced by injection of Aβ (25-35) in the hippocampus. We evaluate object recognition (OR) and social recognition (SR) memory, and removed the rats' hippocampus for biochemical analysis. StrEx improved OR and SR. StrEx combined with GT improved OR and did not improve SR. GT reduced antioxidant capacity and improved acetylcholinesterase activity. Both strength exercise and green tea are neuroprotective against impairments resultant of β-amyloid, but benefits do not add up when the two interventions are associated.

Sarcopenia: Molecular Pathways and Potential Targets for Intervention

Aging is associated with sarcopenia. The loss of strength results in decreased muscle mass and motor function. This process accelerates the progressive muscle deterioration observed in older adults, favoring the presence of debilitating pathologies. In addition, sarcopenia leads to a decrease in quality of life, significantly affecting self-sufficiency. Altogether, these results in an increase in economic resources from the National Health Systems devoted to mitigating this problem in the elderly, particularly in developed countries. Different etiological determinants are involved in the progression of the disease, including: neurological factors, endocrine alterations, as well as nutritional and lifestyle changes related to the adoption of more sedentary habits. Molecular and cellular mechanisms have not been clearly characterized, resulting in the absence of an effective treatment for sarcopenia. Nevertheless, physical activity seems to be the sole strategy to delay sarcopenia and its symptoms. The present review intends to bring together the data explaining how physical activity modulates at a molecular and cellular level all factors that predispose or favor the progression of this deteriorating pathology.

Autonomous climbing: An effective exercise mode with beneficial outcomes of aerobic exercise and resistance training

AIMS

To assess the effects of three specific exercise training modes, aerobic exercise (A), resistance training (R) and autonomous climbing (AC), aimed at proposing a cross-training method, on improving the physical, molecular and metabolic characteristics of mice without many side effects.

MATERIALS AND METHODS

Seven-week-old male mice were randomly divided into four groups: control (C), aerobic exercise (A), resistance training (R), and autonomous climbing (AC) groups. Physical changes in mice were tracked and analysed to explore the similarities and differences of these three exercise modes. Histochemistry, quantitative real-time PCR (RT-PCR), western blot (WB) and metabolomics analysis were performed to identify the underlying relationships among the three training modes.

KEY FINDINGS

Mice in the AC group showed better body weight control, glucose and energy homeostasis. Molecular markers of myogenesis, hypertrophy, antidegradation and mitochondrial function were highly expressed in the muscle of mice after autonomous climbing. The serum metabolomics landscape and enriched pathway comparison indicated that the aerobic oxidation pathway (pentose phosphate pathway, galactose metabolism and fatty acid degradation) and amino acid metabolism pathway (tyrosine, arginine and proline metabolism) were significantly enriched in group AC, suggesting an increased muscle mitochondrial function and protein balance ability of mice after autonomous climbing.

SIGNIFICANCE

We propose a new exercise mode, autonomous climbing, as a convenient but effective training method that combines the beneficial effects of aerobic exercise and resistance training.

Physical Exercise-Mediated Changes in Redox Profile Contribute to Muscle Remodeling After Passive Hand-Rolled Cornhusk Cigarette Smoke Exposure

Consumption of non-traditional cigarettes has increased considerably worldwide, and they can induce skeletal muscle dysfunction. Physical exercise has been demonstrated to be important for prevention and treatment of smoking-related diseases. Therfore, the aim of this study was to investigate the effects of combined physical exercise (aerobic plus resistance exercise) on muscle histoarchitecture and oxidative stress in the animals exposed chronically to smoke from hand-rolled cornhusk cigarette (HRCC). Male Swiss mice were exposed to ambient air or passively to the smoke of 12 cigarettes over three daily sessions (four cigarettes per session) for 30 consecutive days with or without combined physical training. 48 h after the last training session, total leukocyte count was measured in bronchoalveolar lavage fluid (BALF), and the quadriceps were removed for histological/immunohistochemical analysis and measurement of oxidative stress parameters. The effects of HRCC on the number of leukocytes in BALF, muscle fiber diameter, central nuclei, and nuclear factor kappa B (NF-κB) were reverted after combined physical training. In addition, increased myogenic factor 5, tumor necrosis factor alpha (TNFα), reduced transforming growth factor beta (TGF-β), and nitrate levels were observed after physical training. However, the reduction in superoxide dismutase and glutathione/glutathione oxidized ratio induced by HRCC was not affected by the training program. These results suggest the important changes in the skeletal muscle brought about by HRCC-induced alteration in the muscle redox profile. In addition, combined physical exercise contributes to remodeling without disrupting muscle morphology.

Effect of long-term moderate-exercise combined with metformin-treatment on antioxidant enzymes activity and expression in the gastrocnemius of old female Wistar rats

Oxidative stress is known to be involved in the etiology of sarcopenia, a progressive loss of muscle mass and force related to elderly incapacity. A successful intervention to prevent this condition has been exercise-based therapy. Metformin (MTF), an anti-diabetic drug with pleiotropic effects, is known to retain redox homeostasis. However, the combined use of MTF with exercise has shown controversial experimental results. Our research group has shown that MTF-treatment does not limit the benefits provided by exercise, probably by inducing a hormetic response. Hence, our aim was to evaluate the effect of exercise in combination with MTF-treatment on the redox state of old female Wistar rats. Animals were divided into six groups; three groups preformed exercise on a treadmill for 5 days/week for 20 months and the other three were sedentary. Also, two groups of each, exercised and sedentary animals were treated with MTF for 6 or 12 months correspondingly, beside the untreated groups. Rats were euthanized at 24 months. Muscular functionality was analyzed as the relation between the lean mass free of bone with respect to the grip strength. Superoxide dismutase, catalase, and glutathione peroxidase content, enzymatic activity and redox state were determined in the gastrocnemius muscle. Our results showed that the exercised group treated with MTF for 12 months presented higher GSH/GSSG rate and high antioxidant scavenging power in contrast to the MTF-treatment for 6 months, where the beneficial effect was less noticeable.

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.

Remarkable cell recovery from cerebral ischemia in rats using an adaptive escalator-based rehabilitation mechanism

Currently, many ischemic stroke patients worldwide suffer from physical and mental impairments, and thus have a low quality of life. However, although rehabilitation is acknowledged as an effective way to recover patients’ health, there does not exist yet an adaptive training platform for animal tests so far. For this sake, this paper aims to develop an adaptive escalator (AE) for rehabilitation of rats with cerebral ischemia. Rats were observed to climb upward spontaneously, and a motor-driven escalator, equipped with a position detection feature and an acceleration/deceleration mechanism, was constructed accordingly as an adaptive training platform. The rehabilitation performance was subsequently rated using an incline test, a rotarod test, the infarction volume, the lesion volume, the number of MAP2 positive cells and the level of cortisol. This paper is presented in 3 parts as follows. Part 1 refers to the escalator mechanism design, part 2 describes the adaptive ladder-climbing rehabilitation mechanism, and part 3 discusses the validation of an ischemic stroke model. As it turned out, a rehabilitated group using this training platform, designated as the AE group, significantly outperformed a control counterpart in terms of a rotarod test. After the sacrifice of the rats, the AE group gave an average infarction volume of (34.36 ± 3.8)%, while the control group gave (66.41 ± 3.1)%, validating the outperformance of the escalator-based rehabilitation platform in a sense. An obvious difference between the presented training platform and conventional counterparts is the platform mechanism, and for the first time in the literature rats can be well and voluntarily rehabilitated at full capacity using an adaptive escalator. Taking into account the physical diversity among rats, the training strength provided was made adaptive as a reliable way to eliminate workout or secondary injury. Accordingly, more convincing arguments can be made using this mental stress-free training platform.

Acute effects of intense exercise on the antioxidant system in birds: does exercise training help?

The acute effects of an energy-intensive activity such as exercise may alter an animal's redox homeostasis, although these short-term effects may be ameliorated by chronic exposure to that activity, or training, over time. Although well documented in mammals, how energy-intensive training affects the antioxidant system and damage by reactive species has not been investigated fully in flight-trained birds. We examined changes to redox homeostasis in zebra finches exposed to energy-intensive activity (60 min of perch-to-perch flights twice a day), and how exercise training over many weeks affected this response. We measured multiple components of the antioxidant system: an enzymatic antioxidant (glutathione peroxidase, GPx) and non-enzymatic antioxidants (measured by the OXY-adsorbent test) as well as a measure of oxidative damage (d-ROMs). At no point during the experiment did oxidative damage change. We discovered that exposure to energy-intensive exercise training did not alter baseline levels of GPx, but induced exercise-trained birds to maintain a higher non-enzymatic antioxidant status as compared with untrained birds. GPx activity was elevated above baseline in trained birds immediately after completion of the second 1 h flight on each of the three sampling days, and non-enzymatic antioxidants were acutely depleted during flight after 13 and 44 days of training. The primary effect of exercise training on the acute response of the antioxidant system to 2 h flights was increased coordination between the enzymatic (GPx) and non-enzymatic components of the antioxidant system of birds that reduced oxidative damage associated with exercise.

Resistance Exercise Modulates Oxidative Stress Parameters and TNF-α Content in the Heart of Mice with Diet-Induced Obesity

Background

Obesity can be characterized by low-grade chronic inflammation and is associated with an excesso production of reactive oxygen species, factors that contribute to coronary heart disease and other cardiomyopathies.

Objective

To verify the effects of resistance exercise training on oxidative stress and inflammatory parameters on mice with obesity induced by a high-fat diet (HFD).

Methods

24 Swiss mice were divided into 4 groups: standard diet (SD), SD + resistance exercise (SD + RE), diet-induced obesity (DIO), DIO + RE. The animals were fed SD or HFD for 26 weeks and performed resistance exercises in the last 8 weeks of the study. The insulin tolerance test (ITT) and body weight monitoring were performed to assess the clinical parameters. Oxidative stress and inflammation parameters were evaluated in the cardiac tissue. Data were expressed by mean and standard deviation (p < 0.05).

Results

The DIO group had a significant increase in reactive oxygen species levels and lipid peroxidation with reduction after exercise. Superoxide dismutase and the glutathione system showed no significant changes in DIO animals, with an increase in SD + RE. Only catalase activity decreased with both diet and exercise influence. There was an increase in tumor necrosis factor-alpha (TNF-α) in the DIO group, characterizing a possible inflammatory condition, with a decrease when exposed to resistance training (DIO+RE).

Conclusion

The DIO resulted in a redox imbalance in cardiac tissue, but the RE was able to modulate these parameters, as well as to control the increase in TNF-α levels.

Strength training and aerobic exercise alter mitochondrial parameters in brown adipose tissue and equally reduce body adiposity in aged rats

With aging, there is a reduction in mitochondrial activity, and several changes occur in the body composition, including increased adiposity. The dysfunction of mitochondrial activity causes changes and adaptations in tissue catabolic characteristics. Among them, we can mention brown adipose tissue (BAT). BAT's main function is lipid oxidation for heat production, hence playing a role in adaptive thermogenesis induced by environmental factors such as exercise. It is known that exercise causes a series of metabolic changes, including loss body fat; however, there is still no consensus in the academic community about whether both strength and aerobic exercise equally reduces adiposity. Therefore, this study aimed to evaluate the effects of strength training and aerobic exercise regimes on adiposity, proteins regulating mitochondrial activity, and respiratory complexes in BAT of old rats. The rats were divided in two control groups: young control (YC; N = 5), and old control (OC; N = 5), and two exercise groups: strength training (OST; N = 5), and aerobic treadmill training (OAT; N = 5). Rats were subjected to an 8-week exercise regime, and their body composition parameters were evaluated (total body weight, adiposity index, and BAT weight). In addition, mitochondrial biogenesis proteins (PGC-1α, SIRT1, and pAMPK) and respiratory chain activity (complexes I, II/III, III, and IV) were evaluated. Results showed that OST and OAT exercise protocols significantly increased the mitochondrial regulatory molecules and respiratory chain activity, while body fat percentage and adiposity index significantly decreased. Taken together, both OST and OAT exercise increased BAT weight, activity of respiratory complexes, and regulatory proteins in BAT and equally reduced body adiposity.

Beneficial alterations in body composition, physical performance, oxidative stress, inflammatory markers, and adipocytokines induced by long-term high-intensity interval training in an aged rat model

Sarcopenia is associated with loss of muscle mass and function as well as oxidative stress, chronic low-grade inflammatory status, and adipocytokine dysfunction. It has been reported that sarcopenia can be attenuated by exercise training. The purpose of this study was to evaluate whether long-term high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) protocols could differentially modulate changes in body composition, physical performance, inflammatory parameters, and adipocytokines in fat tissues and serum, as well as oxidative parameters and insulin-like growth factor 1 (IGF-1) levels in skeletal muscle tissue of aged rats. Middle-aged (18-month-old) female Sprague Dawley rats (n = 36) were subjected to 8 months of MICT (26-m MICT) or HIIT (26-m HIIT) treadmill training (45 min, 5 times per week), and the results were compared with those of age-matched sedentary controls (26-m SED); 8-month-old (8-m SED) and 18-month-old (18-m SED) rats served as aging sedentary controls. Body composition parameters; physical performance; serum and skeletal muscle oxidative stress parameters; levels of IGF-1, a serum and fat tissue inflammatory marker; adipocytokine (leptin, adiponectin) levels; and plasma glucose and lipid metabolism-related parameters were analyzed among the five groups. The percent fat and body fat to lean mass ratio increased as a main effect with age, whereas 26-m HIIT but not 26-m MICT attenuated these alterations. The 26-m HIIT group showed a larger improvement in grip strength compared to that of 26-m MICT, with a similar increase in inclined plane performance, maximum running speed, and exhaustion over time as compared with the 26-m SED group. Notably, the 26-m HIIT group showed lower high-sensitivity C-reactive protein levels and higher IL-10 in serum compared with those of the 26-m SED and 26-m MICT groups. Both exercise protocols promoted increased skeletal muscle IGF-1 and decreased serum IGF-1 and adiponectin relative to those in the 26-m SED group, whereas only 26-m HIIT dampened the age-related decrease in plasma free fatty acids and increased serum leptin, along with providing lower fat tissue leptin as compared with that in the 26-m SED group. Moreover, the 26-m HIIT group showed lower serum and skeletal muscle malonylaldehyde and skeletal muscle 8-hydroxydeoxyguanosine (8-OHdG) levels than those in the 26-m MICT group, albeit similar decreases in serum and skeletal muscle 4-hydroxynonenal and serum 8-OHdG and increases in skeletal muscle superoxide dismutase 2 activity. In conclusion, HIIT initiated late in life exhibited greater beneficial effects in ameliorating aged-related elevations in oxidative stress and inflammation, as well as dysfunction of circulating adipocytokine levels, than a volume-matched MICT program. HIIT may therefore contribute to improvements in body composition and physical performance changes associated with aging.