Physical exercise, reactive oxygen species and neuroprotection

Relationship between different physical activity parameters and cognitive impairment in middle-aged and older adults: insights from a 4-year longitudinal study

BACKGROUND

Physical activity (PA) is crucial for the prevention and management of chronic diseases and may be associated with cognitive impairment. This study investigated the longitudinal relationship between PA from different parameters (e.g., frequency, duration, intensity, and volume) and the incidence of cognitive impairment in middle-aged and older adults.

METHODS

Data were derived from the China Health and Retirement Longitudinal Study (2011-2015). A total of 891 adults aged 45 and older were included in this study. Cognitive function was assessed using the Telephone Interview for Cognitive Status criteria, focused on episodic memory and executive function. We categorized participants into normal cognition and cognitive impairment groups. Self-reported PA information including frequency, duration, intensity, and volume was collected through a representative survey. Poisson regression analysis was employed to explore the relationship between PA parameters and the incidence of cognitive impairment over four years.

RESULTS

Engaging in moderate or light PA (MPA or LPA) at least three days per week, and vigorous PA (VPA) one to two days per week, was associated with a reduced incidence of cognitive impairment. Additionally, spending 30-119 min per day or 150 min per week or more on any PA intensity was linked to lower cognitive impairment prevalence. Sensitivity analysis, excluding individuals with neurological, mental, or memory impairments, confirmed these findings.

CONCLUSIONS

The findings highlight that the frequency, duration, and volume of VPA, MPA, or LPA are linked to the incidence of cognitive impairment. Regular PA may reduce the risk of cognitive impairment in middle-aged and older adults.

Previous strength training attenuates ouabain-induced bipolar disorder-related behaviors and memory deficits in rats: Involvement of hippocampal ERK/CREB and PI3K/AKT/mTOR pathways

Bipolar disorder (BD) is a central nervous system condition that is typified by fluctuations in mood, oscillating between depressive and manic, and/or hypomanic episodes. The objective of this study was to test the hypothesis that strength training may act as a potent protector against behavioral and neurochemical changes induced by BD. A strength training protocol was performed with adult male Wistar rats, and seven days following the conclusion of training, a single ouabain injection was administered. Following ouabain administration, the animals were subjected to behavioral tests after the seventh (manic period) and fourteenth (depressive period) days. Subsequently, rats were euthanized and the hippocampus was collected for western blotting assays. We demonstrated that strength training provided protection against ouabain-induced behavioral changes, both during the manic and depressive periods, including increased locomotor activity, risk-taking and aggressive-like behaviors, and impaired memory performance. Furthermore, physical training protected against ouabain-induced decrease of neurogenesis/neuroplasticity-related pathways, including BDNF/TrKB/ERK/CREB and PI3K/AKT/mTOR/p70S6K. These findings suggest that strength training has a protective effect, attenuating or preventing BD-induced deficits, and may have therapeutic potential as an adjuvant treatment for this patient population in the future.

Development of a microfluidic wearable electrochemical sensor for the non-invasive monitoring of oxidative stress biomarkers in human sweat

Oxidative stress is widely recognized as a pivotal factor contributing to numerous Central Nervous System (CNS) ailments. The concentrations of hydrogen peroxide (H2O2) and phosphorylated proteins within the human body serve as crucial indicators of oxidative stress. As such, the real-time monitoring of H2O2 and phosphorylated proteins in sweat is vital for the early identification, diagnosis, and management of diseases linked to oxidative stress. In this context, we present a novel microfluidic wearable electrochemical sensor by modifying the electrode with Prussian blue (PB) and loading sulfur-rich vacancy-containing molybdenum disulfide (MoS2-X) onto Multi-walled carbon nanotube (CNTs) to form coaxially layered CNTs/MoS2-X, which was then synthesized with highly dispersed titanium dioxide nanoparticles (TiO2) to synthesize CNTs/MoS2-X/TiO2 composites for the detection of human sweat H2O2 and phosphorylated proteins, respectively. This structure, with its sulfur vacancies and coaxial layering, significantly improved sensitivity of electrochemical sensors, allowing it to detect H2O2 in a range of 0.01-1 mM with a detection limit of 4.80 μM, and phosphoproteins in a range of 0.01-1 mg/mL with a threshold of 0.917 μg/mL. Furthermore, the miniature sensor demonstrates outstanding performance in detecting analytes in both simulated and real sweat. Comprehensive biosafety assessments have validated the compatibility of the electrode material, underscoring the potential of sensor as a reliable and non-invasive method for tracking biomarkers linked to CNS disorders. This microfluidic wearable electrochemical biosensor with high performance and biosafety features shows great promise for the development of cutting-edge wearable technology devices for tracking CNS disease indicators.

Prolonged moderate to vigorous physical activity may lead to a decline in cognitive performance: a Mendelian randomization study

Objective

This study investigates the causal relationship between moderate to vigorous physical activity and cognitive performance.

Methods

Genetic loci strongly related to moderate to vigorous physical activity from genome-wide association studies were used as instrumental variables. These were combined with genetic data on cognitive performance from different Genome-Wide Association Study (GWAS) to conduct a two-sample Mendelian randomization analysis. The primary analysis used inverse variance weighting within a random effects model, supplemented by weighted median estimation, MR-Egger regression and other methods, with results expressed as Beta coefficient.

Results

This study selected 19 SNPs closely related to physical activity as instrumental variables. The multiplicative random-effects Inverse-Variance Weighted (IVW) analysis revealed that moderate to vigorous physical activity was negatively associated with cognitive performance (Beta = -0.551; OR = 0.58; 95% CI: 0.46-0.72; p < 0.001). Consistent results were obtained using the fixed effects IVW model (Beta = -0.551; OR = 0.58; 95% CI: 0.52-0.63; p < 0.001), weighted median (Beta = -0.424; OR = 0.65; 95% CI: 0.55-0.78; p < 0.001), simple mode (Beta = -0.467; OR = 0.63; 95% CI: 0.44-0.90; p < 0.001), and weighted mode (Beta = -0.504; OR = 0.60; 95% CI: 0.44-0.83; p < 0.001). After adjusting for BMI, smoking, sleep duration, and alcohol intake frequency, the multivariate MR analysis also showed a significant association between genetically predicted MVPA and cognitive performance, with Beta of -0.599 and OR = 0.55 (95% CI: 0.44-0.69; p < 0.001).

Conclusion

The findings of this study indicate that genetically predicted moderate to vigorous physical activity may be associated with a decline in cognitive performance.

Unlocking the potential of exercise: harnessing myokines to delay musculoskeletal aging and improve cognitive health

Objectives

This review aims to summarize the common physiological mechanisms associated with both mild cognitive impairment (MCI) and musculoskeletal aging while also examining the relevant literature on how exercise regulation influences the levels of shared myokines in these conditions.

Methods

The literature search was conducted via databases such as PubMed (including MEDLINE), EMBASE, and the Cochrane Library of Systematic Reviews. The searches were limited to full-text articles published in English, with the most recent search conducted on 16 July 2024. The inclusion criteria for this review focused on the role of exercise and myokines in delaying musculoskeletal aging and enhancing cognitive health. The Newcastle‒Ottawa Scale (NOS) was utilized to assess the quality of nonrandomized studies, and only those studies with moderate to high quality scores, as per these criteria, were included in the final analysis. Data analysis was performed through narrative synthesis.

Results

The primary outcome of this study was the evaluation of myokine expression, which included IL-6, IGF-1, BDNF, CTSB, irisin, and LIF. A total of 16 studies involving 633 older adults met the inclusion criteria. The current exercise modalities utilized in these studies primarily consisted of resistance training and moderate-to high-intensity cardiovascular exercise. The types of interventions included treadmill training, elastic band training, aquatic training, and Nordic walking training. The results indicated that both cardiovascular exercise and resistance exercise could delay musculoskeletal aging and enhance the cognitive functions of the brain. Additionally, different types and intensities of exercise exhibited varying effects on myokine expression.

Conclusion

Current evidence suggests that exercise mediates the secretion of specific myokines, including IL-6, IGF-1, BDNF, CTSB, irisin, and LIF, which establish self-regulatory circuits between the brain and muscle. This interaction enhances cognitive function in the brain and improves skeletal muscle function. Future research should focus on elucidating the exact mechanisms that govern the release of myokines, the correlation between the intensity of exercise and the secretion of these myokines, and the distinct processes by which myokines influence the interaction between muscle and the brain.

BDNF-Regulated Modulation of Striatal Circuits and Implications for Parkinson's Disease and Dystonia

Neurotrophins, particularly brain-derived neurotrophic factor (BDNF), act as key regulators of neuronal development, survival, and plasticity. BDNF is necessary for neuronal and functional maintenance in the striatum and the substantia nigra, both structures involved in the pathogenesis of Parkinson's Disease (PD). Depletion of BDNF leads to striatal degeneration and defects in the dendritic arborization of striatal neurons. Activation of tropomyosin receptor kinase B (TrkB) by BDNF is necessary for the induction of long-term potentiation (LTP), a form of synaptic plasticity, in the hippocampus and striatum. PD is characterized by the degeneration of nigrostriatal neurons and altered striatal plasticity has been implicated in the pathophysiology of PD motor symptoms, leading to imbalances in the basal ganglia motor pathways. Given its essential role in promoting neuronal survival and meditating synaptic plasticity in the motor system, BDNF might have an important impact on the pathophysiology of neurodegenerative diseases, such as PD. In this review, we focus on the role of BDNF in corticostriatal plasticity in movement disorders, including PD and dystonia. We discuss the mechanisms of how dopaminergic input modulates BDNF/TrkB signaling at corticostriatal synapses and the involvement of these mechanisms in neuronal function and synaptic plasticity. Evidence for alterations of BDNF and TrkB in PD patients and animal models are reviewed, and the potential of BDNF to act as a therapeutic agent is highlighted. Advancing our understanding of these mechanisms could pave the way toward innovative therapeutic strategies aiming at restoring neuroplasticity and enhancing motor function in these diseases.

Physical exercise in amyotrophic lateral sclerosis: a potential co-adjuvant therapeutic option to counteract disease progression

Amyotrophic lateral sclerosis (ALS) is a fatal disorder characterized by the selective degeneration of upper and lower motor neurons, leading to progressive muscle weakness and atrophy. The mean survival time is two to five years. Although the hunt for drugs has greatly advanced over the past decade, no cure is available for ALS yet. The role of intense physical activity in the etiology of ALS has been debated for several decades without reaching a clear conclusion. The benefits of organized physical activity on fitness and mental health have been widely described. Indeed, by acting on specific mechanisms, physical activity can influence the physiology of several chronic conditions. It was shown to improve skeletal muscle metabolism and regeneration, neurogenesis, mitochondrial biogenesis, and antioxidant defense. Interestingly, all these pathways are involved in ALS pathology. This review will provide a broad overview of the effect of different exercise protocols on the onset and progression of ALS, both in humans and in animal models. Furthermore, we will discuss challenges and opportunities to exploit physiological responses of imposed exercise training for therapeutic purposes.

Physical Exercise-Induced Activation of NRF2 and BDNF as a Promising Strategy for Ferroptosis Regulation in Parkinson's Disease

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra. Ferroptosis, an iron-dependent form of regulated cell death, may contribute to the progression of PD owing to an unbalanced brain redox status. Physical exercise is a complementary therapy that can modulate ferroptosis in PD by regulating the redox system through the activation of nuclear factor (erythroid-derived 2)-like 2 (NRF2) and brain-derived neurotrophic factor (BDNF) signaling. However, the precise effects of physical exercise on ferroptosis in PD remain unclear. In this review, we explored how physical exercise influences NRF2 and BDNF signaling and affects ferroptosis in PD. We further investigated relevant publications over the past two decades by searching the PubMed, Web of Science, and Google Scholar databases using keywords related to physical exercise, PD, ferroptosis, and neurotrophic factor antioxidant signaling. This review provides insights into current research gaps and demonstrates the necessity for future research to elucidate the specific mechanisms by which exercise regulates ferroptosis in PD, including the assessment of different exercise protocols and their long-term effects. Ultimately, exploring these aspects may lead to the development of improved exercise interventions for the better management of patients with PD.

Astrocyte-Microglia Crosstalk: A Novel Target for the Treatment of Migraine

Migraine is a pervasive neurologic disease closely related to neurogenic inflammation. The astrocytes and microglia in the central nervous system are vital in inducing neurogenic inflammation in migraine. Recently, it has been found that there may be a crosstalk phenomenon between microglia and astrocytes, which plays a crucial part in the pathology and treatment of Alzheimer's disease and other central nervous system diseases closely related to inflammation, thus becoming a novel hotspot in neuroimmune research. However, the role of the crosstalk between microglia and astrocytes in the pathogenesis and treatment of migraine is yet to be discussed. Based on the preliminary literature reports, we have reviewed relevant evidence of the crosstalk between microglia and astrocytes in the pathogenesis of migraine and summarized the crosstalk pathways, thereby hoping to provide novel ideas for future research and treatment.

The microarchitecture and chemical composition of the femur neck of senescent female rats after different physical training protocols

A sedentary lifestyle, coupled with a decrease in estrogen, impairs bone homeostasis, favoring to the development of osteopenia and osteoporosis, both recognized as risk factors for fractures. Here, we investigated the quality of the femur, particularly the femur neck region, and the ambulation performance of senescent rats subjected to three different physical training protocols during the periestropause period. Forty-eight female rats, 18 months of age, were subjected to a 120-day training period, three times a week. The rats were distributed into four groups: aerobic training (AT), strength training (ST), concurrent training (CT), or no training (NT). After the experimental period, at 21 months of age, ambulation performance and femur were analyzed using microtomography, Raman stereology, densitometry, and mechanical strength tests. The results demonstrated greater remodeling activity and improvement in resistance and bone microarchitecture in the femur neck of senescent female rats after undergoing physical training. Our verified higher intensities of bands related to collagen, phosphate, amide III, and amide I. Furthermore, the analysis of the secondary collagen structures indicated alterations in the collagen network due to the exercise, resulting in increased bone strength. Both AT and strength-based training proved beneficial, with AT showing greater adaptations in bone density and stiffness in the femur, while strength-based training greater adaptations in trabecular and cortical structure. These insights contribute to the understanding of the potential interventions for preventing osteopenia and osteoporosis, which are critical risk factors for fractures.

The Relationship between Physical Activity, Physical Fitness, Cognition, and Academic Outcomes in School-Aged Latino Children: A Scoping Review

This scoping review provides an overview of the relationship between physical activity, physical fitness, cognition, and academic outcomes in Latino school-aged children and identifies areas for future research. A primary search was conducted in PubMed, PsycINFO, Web of Science, and ERIC for original-research articles meeting the inclusion criteria; the search results were uploaded into PICO Portal and assessed by two independent reviewers. Of the 488 initial search results, 50 articles were eligible for full-text review, and 38 were included in this review. Most studies were cross-sectional, conducted in the United States or Chile, and included children 5-18 years old. Overall, the majority of articles reported positive associations between physical activity or physical fitness and cognitive outcomes (n = 11/12; 91.7%), and physical activity or physical fitness and academic outcomes (n = 22/28; 78.6%). In sum, this review provided consistent evidence for higher amounts of physical activity and greater physical fitness to be associated with various positive cognitive and academic outcomes in a school-aged Latino population. This scoping review also elucidated a substantial gap in the research regarding study design, with a discernible lack of interventional efforts. Future studies should test physical activity interventional strategies to optimize cognitive and academic outcomes in school-aged Latino populations.

Myelin repair of spinal cord injury in adult mice induced by treadmill training upregulated peroxisome proliferator-activated receptor gamma coactivator 1 alpha

Growing evidence has proven the efficacy of physical exercise in remyelination and motor function performance after spinal cord injury (SCI). However, the molecular mechanisms of treadmill training on myelin repair and functional recovery after SCI have not yet been fully studied. Here, we explored the effect of treadmill training on upregulating peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α)-mediated myelin repair and functional recovery in a mouse model of thoracic T10 contusion injury. A 4-week treadmill training scheme was conducted on mice with SCI. The expression levels of oligodendrogenesis-related protein and PGC1α were detected by immunofluorescence, RNA fluorescence in situ hybridization and western blotting. Transmission electron microscopy (TEM) was used to observe myelin structure. The Basso Mouse Scale (BMS) and CatWalk automated gait analysis system were used for motor function recovery evaluation. Motor evoked potentials (MEPs) were also identified. In addition, adeno-associated virus (AAV)-mediated PGC1α knockdown in OLs was used to further unravel the role of PGC1α in exercise-induced remyelination. We found that treadmill training boosts oligodendrocyte precursor cells (OPCs) proliferation, potentiates oligodendrocytes (OLs) maturation, and increases myelin-related protein and myelin sheath thickness, thus impelling myelin repair and hindlimb functional performance as well as the speed and amplitude of nerve conduction after SCI. Additionally, downregulating PGC1α through AAV attenuated these positive effects of treadmill training. Collectively, our results suggest that treadmill training enhances remyelination and functional recovery by upregulating PGC1α, which should provide a step forward in the understanding of the effects of physical exercise on myelin repair.

Lifetime Physical Activity and Late-Life Mild Cognitive Impairment in Community-Dwelling Older Adults

OBJECTIVES

Regular physical activity throughout life is generally recommended to prevent dementia; however, there is little evidence regarding the association between lifetime physical activity and mild cognitive impairment (MCI), which often precedes dementia. This study aimed to examine the association of lifetime physical activity and their transitions with late-life MCI.

DESIGN

A population-based case-control study.

SETTING AND PARTICIPANTS

A total of 2968 Japanese community-dwelling older adults aged ≥70 years without dementia.

METHODS

We evaluated the participants' early-, mid-, and late-life physical activity habits and categorized their transitions across life stages. Cognitive functions in late life were assessed for memory, attention, executive function, and processing speed; functional impairment in one or more cognitive domains was defined as MCI.

RESULTS

Regular physical activity in early life was not significantly associated with late-life MCI [odds ratio (OR), 0.80; 95% CI, 0.63-1.02], although those in mid-life (OR, 0.64; 95% CI, 0.51-0.81) and late-life (OR, 0.74; 95% CI, 0.59-0.91) were associated with lower odds of late-life MCI. Compared with nonexercisers, participants who acquired new habits of physical activity during mid- or late-life (OR, 0.71; 95% CI, 0.55-0.91) and those who maintained physical activity throughout their life span (OR, 0.61; 95% CI, 0.42-0.87) had lower odds of late-life MCI; those who stopped regular activity during mid- or late-life did not (OR, 0.79; 95% CI, 0.58-1.06).

CONCLUSIONS AND IMPLICATIONS

While physical activity throughout the life span is associated with the lowest odds of MCI, starting regular physical activity, even later in life, confers a benefit and should be encouraged as a "lifelong approach" to MCI risk reduction.

Changes of brain-derived neurotrophic factor (BDNF) levels after different exercise protocols: a systematic review of clinical studies in Parkinson's disease

Background: Brain-Derived Neurotrophic Factor (BDNF) serum levels are reduced in patients with Parkinson's Disease (PD). Objectives: This study aimed to assess the effect of exercise intensity, volume and type on BDNF levels in patients with PD. Methods: We searched clinicaltrials.gov, CINAHL, Embase, PubMed, Scopus, Web of Science for both controlled and non-controlled studies in patients with PD, published between 2003 and 2022, which assessed Brain-Derived Neurotrophic Factor before and after different exercise protocols. Exercise intensity was estimated using a time-weighted average of Metabolic Equivalent of Task (MET), while exercise volume was estimated by multiplying MET for the duration of exercise. Exercise types were classified as aerobic, resistance, balance and others. We computed two distinct standardized measures of effects: Hedges' g to estimate differences between experimental and control group in pre-post intervention BDNF changes, and Cohen's d to measure pre-post intervention changes in BDNF values for each study arm. Meta-regression and linear regression were used to assess whether these effect measures were associated with intensity, volume and type. PROSPERO registration number: CRD42023418629. Results: Sixteen studies (8 two-arm trials and 8 single-arm trials) including 370 patients with PD were eligible for the systematic review. Selected studies had a large variability in terms of population and intervention characteristics. The meta-analysis showed a significant improvement in BDNF levels in the exercise group compared to the control group, Hedges' g = 0.70 (95% CI: 0.03, 1.38), with substantial heterogeneity (I2 = 76.0%). Between-group differences in intensity were positively associated with change in BDNF in a subset of 5 controlled studies. In the analysis which included non-controlled studies, intensity and total exercise volume were both positively associated with BDNF change. No difference was found according to exercise type. Conclusion: Exercises of greater intensity may increase BDNF levels in patients with PD, while the role of volume of exercise needs to be further explored.

The possible positive effects of physical exercise on the global motion perception aging: the cognitive mechanism

Background

Sensitivity to global motion perception (GMP) decreases gradually with age, and the mechanism to effectively alleviate its aging process is still unclear. This study aimed to examine the impact and mechanism of exercise on GMP aging.

Methods

This study adopted the global motion direction discrimination task and used motion coherence thresholds to assess GMP sensitivity. It adopted the perceptual template model (PTM) to fit the GMP processing efficiency.

Results

The threshold for the elderly group with no exercise was higher than that of the elderly group with exercise, while the threshold of the latter was higher than that of the youth group. The results of the model fitting showed that both models, Aa and Af, corresponding to the elderly group with exercise and the elderly group with no exercise, respectively, were the best-fitted models when compared with that of the youth group. Compared to the elderly group with no exercise, models Aa and Af, were the best-fitted models.

Conclusion

These results showed that good exercise habits might have a certain degree of positive effect on GMP aging, by lower their internal additive noise (Aa), and improve the ability to eliminate external noise (Af).

The multifaceted benefits of walking for healthy aging: from Blue Zones to molecular mechanisms

Physical activity, including walking, has numerous health benefits in older adults, supported by a plethora of observational and interventional studies. Walking decreases the risk or severity of various health outcomes such as cardiovascular and cerebrovascular diseases, type 2 diabetes mellitus, cognitive impairment and dementia, while also improving mental well-being, sleep, and longevity. Dose-response relationships for walking duration and intensity are established for adverse cardiovascular outcomes. Walking's favorable effects on cardiovascular risk factors are attributed to its impact on circulatory, cardiopulmonary, and immune function. Meeting current physical activity guidelines by walking briskly for 30 min per day for 5 days can reduce the risk of several age-associated diseases. Additionally, low-intensity physical exercise, including walking, exerts anti-aging effects and helps prevent age-related diseases, making it a powerful tool for promoting healthy aging. This is exemplified by the lifestyles of individuals in Blue Zones, regions of the world with the highest concentration of centenarians. Walking and other low-intensity physical activities contribute significantly to the longevity of individuals in these regions, with walking being an integral part of their daily lives. Thus, incorporating walking into daily routines and encouraging walking-based physical activity interventions can be an effective strategy for promoting healthy aging and improving health outcomes in all populations. The goal of this review is to provide an overview of the vast and consistent evidence supporting the health benefits of physical activity, with a specific focus on walking, and to discuss the impact of walking on various health outcomes, including the prevention of age-related diseases. Furthermore, this review will delve into the evidence on the impact of walking and low-intensity physical activity on specific molecular and cellular mechanisms of aging, providing insights into the underlying biological mechanisms through which walking exerts its beneficial anti-aging effects.

Molecular mechanisms underlying physical exercise-induced brain BDNF overproduction

Accumulating evidence supports that physical exercise (EX) is the most effective non-pharmacological strategy to improve brain health. EX prevents cognitive decline associated with age and decreases the risk of developing neurodegenerative diseases and psychiatric disorders. These positive effects of EX can be attributed to an increase in neurogenesis and neuroplastic processes, leading to learning and memory improvement. At the molecular level, there is a solid consensus to involve the neurotrophin brain-derived neurotrophic factor (BDNF) as the crucial molecule for positive EX effects on the brain. However, even though EX incontestably leads to beneficial processes through BDNF expression, cellular sources and molecular mechanisms underlying EX-induced cerebral BDNF overproduction are still being elucidated. In this context, the present review offers a summary of the different molecular mechanisms involved in brain's response to EX, with a specific focus on BDNF. It aims to provide a cohesive overview of the three main mechanisms leading to EX-induced brain BDNF production: the neuronal-dependent overexpression, the elevation of cerebral blood flow (hemodynamic hypothesis), and the exerkine signaling emanating from peripheral tissues (humoral response). By shedding light on these intricate pathways, this review seeks to contribute to the ongoing elucidation of the relationship between EX and cerebral BDNF expression, offering valuable insights into the potential therapeutic implications for brain health enhancement.

Nickel and aluminium mixture elicit memory impairment by activation of oxidative stress, COX-2, and diminution of AChE, BDNF and NGF levels in cerebral cortex and hippocampus of male albino rats

This study evaluated nickel and aluminium-induced neurotoxicity, as a binary metal mixture. Twenty-eight male Sprague Dawley albino rats were weight-matched and divided into four groups. Group 1 (control) received deionized water. Group 2 and 3 received Aluminium (1 mg/kg) and Nickel (0.2 mg/kg) respectively, while Group 4 received Ni and Al mixture HMM three times a week orally for 90 days. Barnes maze tests was performed. Rats were sacrificed under pentobarbital anaesthesia, cerebral cortex and hippocampus were separated, and metal levels were measured using Atomic Absorption Spectroscopy (AAS). Malondialdehyde (MDA), catalase (CAT), glutathione content (GSH), superoxide dismutase (SOD), glutathione peroxidase (GPx), Brain Derived Neurotrophic Factor (BDNF), Nerve growth factor NGF, cyclo-oxygenase COX-2 and Acetylcholinesterase (AChE) were assayed using ELISA kits. Ni/Al binary mixture exposed rats showed a shorter latency period (though not significant) of 3.21 ± 1.40 s in comparison to 3.77 ± 1.11 (Ni only) and 3.99 ± 1.16(Al only). Ni/Al mixture gp had the lowest levels of Mg in both the hippocampus and frontal cortex when compared with the individual metals. In the hippocampus Al only exposed rats significantly showed p < 0.05 higher iron and Ca levels in comparison to Ni/Al mixture. Al alone significantly showed p < 0.05 lower levels of Fe but higher Ca than the Ni/Al mixture group. Exposure to Al only showed lower levels of BDNF in comparison to Ni/Al combination, whereas Ni/Al mixture gp had lower levels of NGF in comparison to the individual metals in the hippocampus. In the frontal cortex Ni only, group showed significantly lower BDNF in comparison to Ni/Al mixture whereas the mixture showed significantly lower NGF when compared with Al only group. There were higher levels of COX-2 in the Ni/Al mixture than individual metal treated rats in both hippocampus and frontal cortex. AChE levels in the Ni/Al mixture group was higher than Ni or Al only gps in the hippocampus whereas in the frontal cortex, Ni/Al exposed rats showed significantly lower AChE levels in comparison to Al only group. Ni, Al and Ni/Al mixture exhibited memory impairment by activation of oxidative stress, COX-2, and diminution of AChE, BDNF and NGF levels in cerebral cortex and hippocampus. The BDNF-COX-2 AChE signalling pathway may be involved in the neurotoxicity of Ni and Al.

Voluntary exercise does not increase gastrointestinal motility but increases spatial memory, intestinal eNOS, Akt levels, and Bifidobacteria abundance in the microbiome

The interaction between the gut and brain is a great puzzle since it is mediated by very complex mechanisms. Therefore, the possible interactions of the brain-exercise-intestine-microbiome axis were investigated in a control (C, N = 6) and voluntarily exercised (VE, N = 8) middle-aged rats. The endurance capacity was assessed by VO2max on the treadmill, spatial memory by the Morris maze test, gastrointestinal motility by EMG, the microbiome by 16S RNA gene amplicon sequencing, caveolae by electron microscopy, and biochemical assays were used to measure protein levels and production of reactive oxygen species (ROS). Eight weeks of voluntary running increased VO2max, and spatial memory was assessed by the Morris maze test but did not significantly change the motility of the gastrointestinal tract or production of ROS in the intestine. The protein kinase B (Akt) and endothelial nitric oxide synthase (eNOS) protein levels significantly increased in the intestine, while peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), mitochondrial transcription factor A (TFAM), nuclear respiratory factor 1 (NFR1), SIRT1, SIRT3, nicotinamide phosphoribosyl transferase (NAMPT), and nuclear factor κB (NF-κB) did not change. On the other hand, voluntary exercise increased the number of caveolae in the smooth muscles of the intestine and relative abundance of Bifidobacteria in the microbiome, which correlated with the Akt levels in the intestine. Voluntary exercise has systemic effects and the relationship between intestinal Akt and the microbiome of the gastrointestinal tract could be an important adaptive response.

Exerkines and redox homeostasis

Exercise physiology has gained increasing interest due to its wide effects to promote health. Recent years have seen a growth in this research field also due to the finding of several circulating factors that mediate the effects of exercise. These factors, termed exerkines, are metabolites, growth factors, and cytokines secreted by main metabolic organs during exercise to regulate exercise systemic and tissue-specific effects. The metabolic effects of exerkines have been broadly explored and entail a promising target to modulate beneficial effects of exercise in health and disease. However, exerkines also have broad effects to modulate redox signaling and homeostasis in several cellular processes to improve stress response. Since redox biology is central to exercise physiology, this review summarizes current evidence for the cross-talk between redox biology and exerkines actions. The role of exerkines in redox biology entails a response to oxidative stress-induced pathological cues to improve health outcomes and to modulate exercise adaptations that integrate redox signaling.

Alzheimer's Disease Treatment: The Search for a Breakthrough

As the search for modalities to cure Alzheimer's disease (AD) has made slow progress, research has now turned to innovative pathways involving neural and peripheral inflammation and neuro-regeneration. Widely used AD treatments provide only symptomatic relief without changing the disease course. The recently FDA-approved anti-amyloid drugs, aducanumab and lecanemab, have demonstrated unclear real-world efficacy with a substantial side effect profile. Interest is growing in targeting the early stages of AD before irreversible pathologic changes so that cognitive function and neuronal viability can be preserved. Neuroinflammation is a fundamental feature of AD that involves complex relationships among cerebral immune cells and pro-inflammatory cytokines, which could be altered pharmacologically by AD therapy. Here, we provide an overview of the manipulations attempted in pre-clinical experiments. These include inhibition of microglial receptors, attenuation of inflammation and enhancement of toxin-clearing autophagy. In addition, modulation of the microbiome-brain-gut axis, dietary changes, and increased mental and physical exercise are under evaluation as ways to optimize brain health. As the scientific and medical communities work together, new solutions may be on the horizon to slow or halt AD progression.

Exercise preconditioning attenuates cerebral ischemia-induced neuronal apoptosis, Th17/Treg imbalance, and inflammation in rats by inhibiting the JAK2/STAT3 pathway

BACKGROUND

Exercise preconditioning (EP) is essential for preventing ischemic stroke. Recent studies have shown that EP exerts neuroprotective effects in the cerebral ischemia-reperfusion injury model. Nonetheless, there have been few reports on the relationship between EP and the Th17/Treg balance. Moreover, it is unclear whether the JAK2/STAT3 pathway is responsible for the neuroprotective effect of EP. Therefore, we aimed to explore the impact of EP, other than the anti-inflammatory and antiapoptotic functions, on the Th17/Treg balance via the JAK2/STAT3 pathway in a middle cerebral artery occlusion (MCAO)-induced model.

RESULTS

Fifty rats were randomly allocated into five groups, including the sham group (n = 10), EP+sham group (n = 10), MCAO group (n = 10), EP+MCAO group (n = 10), and EP+MCAO+JAK2/STAT3 pathway agonist (coumermycin A1, CA1) group (n = 10). The results indicated that EP alleviated neurological deficits, reduced infarct volume, and ameliorated neuronal apoptosis induced by MCAO. Additionally, the MCAO-induced Th17/Treg imbalance could be rectified by EP. The decreased levels of IL-10 and Foxp3 and increased IL-17 and RORα in the MCAO group were reversed by EP treatment. Regarding inflammation, EP reduced the concentrations of IL-6 and IL-17 and elevated those of IL-10 and TGF-β. The neuroprotective effects of EP were accompanied by decreased phosphorylation of JAK2 and STAT3. Furthermore, CA1 pretreatment diminished all the beneficial effects of EP partially.

CONCLUSION

Our findings suggest that EP contributes to attenuating neuronal apoptosis, Th17/Treg imbalance, and inflammation induced by MCAO via inhibiting the JAK2/STAT3 pathway, indicating its therapeutic potential in ischemic stroke.

Antioxidants and Sports Performance

The role of reactive oxygen species and antioxidant response in training adaptations and sports performance has been a large issue investigated in the last few years. The present review aims to analyze the role of reactive oxygen species and antioxidant response in sports performance. For this aim, the production of reactive oxygen species in physical activities, the effect of reactive oxygen species on sports performance, the relationship between reactive oxygen species and training adaptations, inflammation, and the microbiota, the effect of antioxidants on recovery and sports performance, and strategies to use antioxidants supplementations will be discussed. Finally, practical applications derived from this information are discussed. The reactive oxygen species (ROS) production during physical activity greatly influences sports performance. This review concludes that ROS play a critical role in the processes of training adaptation induced by resistance training through a reduction in inflammatory mediators and oxidative stress, as well as appropriate molecular signaling. Additionally, it has been established that micronutrients play an important role in counteracting free radicals, such as reactive oxygen species, which cause oxidative stress, and the effects of antioxidants on recovery, sports performance, and strategies for using antioxidant supplements, such as vitamin C, vitamin E, resveratrol, coenzyme Q10, selenium, and curcumin to enhance physical and mental well-being.

Oxidative stress, inflammation and hormesis: The role of dietary and lifestyle modifications on aging

Oxidative stress (OS) is primarily caused by the formation of free radicals and reactive oxygen species; it is considered as one of the prominent factors in slowing down and degrading cellular machinery of an individual, and it eventually leads to aging and age-related diseases by its continuous higher state. The relation between molecular damage and OS should be particularized to understand the beginning of destruction at the cellular levels, extending outwards to affect tissues, organs, and ultimately to the organism. Several OS biomarkers, which are established at the biomolecular level, are useful in investigating the disease susceptibility during aging. Slowing down the aging process is a matter of reducing the rate of oxidative damage to the cellular machinery over time. The breakdown of homeostasis, the mild overcompensation, the reestablishment of homeostasis, and the adaptive nature of the process are the essential features of hormesis, which incorporates several factors, including calorie restriction, nutrition and lifestyle modifications that play an important role in reducing the OS. In the current review, along with the concept and theories of aging (with emphasis on free radical theory), various manifestations of OS with special attention on mitochondrial dysfunction and age-related diseases have been discussed. To alleviate the OS, hormetic approaches including caloric restriction, exercise, and nutrition have also been discussed.

Effect of Single Bout of Moderate and High Intensity Interval Exercise on Brain Derived Neurotrophic Factor and Working Memory in Young Adult Females

Objectives

The objectives of the study were to determine the effect of moderate-intensity exercise (MIE) and high-intensity interval exercise (HIIE) on serum brain-derived neurotrophic factor (BDNF) levels and working memory (WM) in young adult females.

Methodology

This study was conducted in the Physiology Department, Khyber Girls Medical College Peshawar. Young adult females (n = 22), with a mean age of 20±2 years were recruited for two experimental sessions of MIE and HIIE, respectively. Baseline and post exercise blood samples were taken for determination of serum BDNF level and backward digit span test (BDST) for assessment of working memory in both sessions.

Results

Serum BDNF levels pre and post MIE were 707±448 pg/ml and 829±476 pg/ml (p = 0.006) respectively while pre and post HIIE were 785±329 pg /ml and 1116±379 pg/ml (p < 0.001) respectively. BDST scores were significantly high at post intervention for both MIE (p = 0.05) and HIIE (p 0.001).

Conclusions

Altogether our findings showed that both MIE and HIIE significantly increased serum BDNF levels and working memory in young adult females.

The Effects of Six Weeks of Endurance Training and CGRP Inhibition on Nrf2 and AKT Expression in the Hippocampal Tissue of Male Wistar Rats

Purpose

To study the effects of a six-week endurance training protocol and calcitonin gene-related peptide (CGRP) inhibition on the nuclear factor erythroid 2-related factor 2 (Nrf2) and protein kinase B (PKB) or AKT expression in the hippocampal tissue of male Wistar rats. Main Methods. Building on a controlled experimental design with a posttest, 28 healthy Wistar male rats were randomly assigned to four groups (n = 7 per group), including control, control+CGRP inhibition, endurance training, and endurance training+CGRP inhibition groups. The training groups were trained for six weeks. Rats in the CGRP inhibition group received CGRP receptor antagonist daily (0.25 mg/kg) via intravenous (IV) injection. The Nrf2 and AKT (PKB) expression was measured using the real-time PCR technique.

Results

In the endurance training group, Nrf2 expression in the hippocampal tissue was increased significantly more than in other groups (P < 0.05). There was also a significant increase in the AKT expression in the endurance training group compared to the control group (P = 0.048) and in the endurance training+CGRP inhibition compared to the control group (P = 0.012). In addition, there was no significant relationship between AKT (PKB) and Nrf2 (r = −0.27, n = 28, P = 0.16).

Conclusion

Endurance training alone has been able to increase Nrf2 and AKT (PKB) mRNA levels in the hippocampal tissue, considering that endurance training had no significant effect on AKT and Nrf2 expression after adding to CGRP inhibition.

Light intensity physical activity is beneficially associated with brain volume in older adults with high cardiovascular risk

Background

Older people with high cardiovascular risk, including those without cardiovascular diseases, are an at-risk population for dementia. Regular physical activity is generally recommended to maintain brain health; however, the optimal intensity of physical activity for maintaining brain volume in older adults with cardiovascular risk remains unclear. We examined the associations between intensity-specific physical activity and brain volume stratified by absolute cardiovascular risk level in older adults without cardiovascular diseases.

Methods and results

This cross-sectional study involved 725 community-dwelling older Japanese adults without cardiovascular diseases. We estimated absolute cardiovascular risk using the World Health Organization risk estimation charts, which include variables such as age, sex, diabetes mellitus, smoking, systolic blood pressure, and total cholesterol, and stratified cardiovascular risk level into three risk categories: low (≤ 9%), moderate (10–14%), and high (≥15%). We measured daily physical activity using a triaxial accelerometer, and calculated the average time spent in moderate-to-vigorous intensity physical activity (MVPA) and light intensity physical activity (LPA). We performed brain T1-weighted magnetic resonance imaging and calculated the volume of the cortical gray matter, subcortical gray matter, and cerebral white matter, using the FreeSurfer software. In the overall sample, multivariable linear regression analysis showed that greater MVPA was significantly associated with greater volume of the cortical gray matter and cerebral white matter, and greater LPA was significantly associated with greater volume of the cerebral white matter. Additionally, in the analysis of the sample stratified by absolute cardiovascular risk level, cerebral white matter volume was significantly associated with both MVPA and LPA in the high cardiovascular risk group.

Conclusions

The association between physical activity and brain volume differed according to cardiovascular risk level in community-dwelling older adults. In a population at high cardiovascular risk, maintaining or increasing LPA might be a practical and achievable strategy for healthy brain aging.

Potential Effects of Nrf2 in Exercise Intervention of Neurotoxicity Caused by Methamphetamine Oxidative Stress

Methamphetamine can cause oxidative stress-centered lipid peroxidation, endoplasmic reticulum stress, mitochondrial dysfunction, excitatory neurotoxicity, and neuroinflammation and ultimately lead to nerve cell apoptosis, abnormal glial cell activation, and dysfunction of blood-brain barrier. Protecting nerve cells from oxidative destroy is a hopeful strategy for treating METH use disorder. Nrf2 is a major transcriptional regulator that activates the antioxidant, anti-inflammatory, and cell-protective gene expression through endogenous pathways that maintains cell REDOX homeostasis and is conducive to the survival of neurons. The Nrf2-mediated endogenous antioxidant pathway can also prevent neurodegenerative effects and functional defects caused by METH oxidative stress. Moderate exercise activates this endogenous antioxidant system, which involves in many diseases, including neurodegenerative diseases. Based on evidence from existing literature, we argue that appropriate exercise can play an endogenous antioxidant regulatory role in the Nrf2 signaling pathway to reduce a number of issues caused by METH-induced oxidative stress. However, more experimental evidence is needed to support this idea. In addition, further exploration is necessary about the different effects of various parameters of exercise intervention (such as exercise mode, time, and intensity) on the Nrf2 signaling pathway intervention. Whether there are synergistic effects between exercise and plant-derived Nrf2 activators is worth further investigation.

Multimodal Benefits of Exercise in Patients With Multiple Sclerosis and COVID-19

Multiple sclerosis (MS) is a demyelinating disease characterized by plaque formation and neuroinflammation. The plaques can present in various locations, causing a variety of clinical symptoms in patients with MS. Coronavirus disease-2019 (COVID-19) is also associated with systemic inflammation and a cytokine storm which can cause plaque formation in several areas of the brain. These concurring events could exacerbate the disease burden of MS. We review the neuro-invasive properties of SARS-CoV-2 and the possible pathways for the entry of the virus into the central nervous system (CNS). Complications due to this viral infection are similar to those occurring in patients with MS. Conditions related to MS which make patients more susceptible to viral infection include inflammatory status, blood-brain barrier (BBB) permeability, function of CNS cells, and plaque formation. There are also psychoneurological and mood disorders associated with both MS and COVID-19 infections. Finally, we discuss the effects of exercise on peripheral and central inflammation, BBB integrity, glia and neural cells, and remyelination. We conclude that moderate exercise training prior or after infection with SARS-CoV-2 can produce health benefits in patients with MS patients, including reduced mortality and improved physical and mental health of patients with MS.

Exercise and Syzygium aromaticum reverse memory deficits, apoptosis and mitochondrial dysfunction of the hippocampus in Alzheimer's disease

ETHNOPHARMACOLOGICAL RELEVANCE

Alzheimer's disease (AD), the most common disease in the brain, is associated with cognitive and mitochondrial dysfunction. Emerging evidence suggests that endurance training and Syzygium aromaticum (L.) Merrill and Perry (Myrtaceae) (commonly referred to as clove) are effective interventions to maintain oxidative balance and improve cognitive function.

AIM OF THE STUDY

The present study aimed to investigate the effect of endurance training and clove oil affect spatial memory, apoptosis, mitochondrial homeostasis, and cognitive function in Alzheimer's rats.

MATERIALS AND METHODS

81 rats were randomly assigned to 9 groups: Healthy (H), sham (sh), Healthy-exercise (HE), Healthy-clove (HC), Healthy-exercise-clove (HEC), Alzheimer's (A), Alzheimer's-exercise (AE), Alzheimer's-clove (AC), and Alzheimer's-exercise-clove (AEC). Alzheimer's induction was induced by the injection of 1-42 amyloid into the CA1 region of the hippocampus. The exercise training protocol was performed for 3 weeks, every day for 30 min in swimming training, and clove oil supplementation (0.1 mg/kg) was gavaged daily for 3 weeks in the supplement rat. Shuttle box test was used to measure spatial memory after the last training session, and to determine the mRNAs and protein levels and apoptosis, Real-Time PCR, immunofluorescent, and tunnel methods were used, respectively.

RESULTS

Alzheimer's caused a significant decrease in the PRDX6 and GCN5L1 mRNAs and protein levels and a significant increase in apoptosis in the hippocampus of the Alzheimer's group compared to the control group (P = 0.001). Alzheimer's also reduced the time delay in entering the dark environment and increased the time spent in the dark environment (P = 0.001). Following endurance training and consumption of clove oil, spatial memory (P = 0.001), apoptosis (P = 0.001) and mRNAs and protein levels of PRDX6 (P = 0.001) and GCN5L1 (P = 0.017), were recovered in AE, AC and AEC groups, as compared with A group.

CONCLUSION

Swimming training and consumption of clove can possibly be considered as an effective intervention to maintain oxidative balance and improve mitochondrial homeostasis in Alzheimer's disease.

The impact of physical activity on blood inflammatory cytokines and neuroprotective factors in individuals with mild cognitive impairment: a systematic review and meta-analysis of randomized-controlled trials

BACKGROUND

Accumulated evidence has proved that both neuroinflammation and neuroprotection existing at the stage of mild cognitive impairment (MCI) may mediate its progression, which can conversely be modulated by physical activity (PA). However, further research is needed to clarify which factors are involved in that process.

OBJECTIVES

To identify the impact of PA on inflammatory cytokines and neuroprotective factors in individuals with MCI.

METHODS

Four databases [PubMed, Cochrane Library, Cochrane Library (Trials), Embase and Web of Science Core Collection] were searched from their inception to October 2021 for randomized-controlled trials (RCTs) assessing the biochemical effect of PA on biomarkers in participants with MCI. Pooled effect size was calculated by the standardized mean difference (SMD).

RESULTS

A total of 13 RCTs involving 514 participants by reporting 8 inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, -6, -8, -10, -15, C-reactive protein (CRP) and interferon-γ (IFN-γ) and 5 neuroprotective factors (brain-derived neurotrophic factor (BDNF), insulin-like growth factor (IGF-1), vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2), irisin] were included. The meta-analysis showed that PA had positive effects on decreasing TNF-α (SMD =  - 0.32, 95% CI - 0.58 to 0.07, p = 0.01; I² = 32%) and CRP (SMD = - 0.68, 95% CI - 1.05 to 0.32, p = 0.0002; I² = 18%), while significantly improving BDNF (SMD = 0.32, 95% CI 0.09-0.56, p = 0.007; I² = 42%) and IGF-1 (SMD = 0.42, 95% CI 0.03-0.81, p = 0.03; I² = 0%).

CONCLUSION

PA had a certain effect on inhibiting inflammatory cytokines but promoting neuroprotective factors in individuals with MCI which may provide a possible explanation for the potential molecular mechanism of PA on cognitive improvement.

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

Simple Summary

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

Abstract

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

Active Life for Brain Health: A Narrative Review of the Mechanism Underlying the Protective Effects of Physical Activity on the Brain

A growing body of evidence clearly indicates the beneficial effects of physical activity (PA) on cognition. The importance of PA is now being reevaluated due to the increase in sedentary behavior in older adults during the COVID-19 pandemic. Although many studies in humans have revealed that PA helps to preserve brain health, the underlying mechanisms have not yet been fully elucidated. In this review, which mainly focuses on studies in humans, we comprehensively summarize the mechanisms underlying the beneficial effects of PA or exercise on brain health, particularly cognition. The most intensively studied mechanisms of the beneficial effects of PA involve an increase in brain-derived neurotrophic factor (BDNF) and preservation of brain volume, especially that of the hippocampus. Nonetheless, the mutual associations between these two factors remain unclear. For example, although BDNF presumably affects brain volume by inhibiting neuronal death and/or increasing neurogenesis, human data on this issue are scarce. It also remains to be determined whether PA modulates amyloid and tau metabolism. However, recent advances in blood-based biomarkers are expected to help elucidate the beneficial effects of PA on the brain. Clinical data suggest that PA functionally modulates cognition independently of neurodegeneration, and the mechanisms involved include modulation of functional connectivity, neuronal compensation, neuronal resource allocation, and neuronal efficiency. However, these mechanisms are as yet not fully understood. A clear understanding of the mechanisms involved could help motivate inactive persons to change their behavior. More accumulation of evidence in this field is awaited.

Hippocampal Oxidative Stress Induced by Radiofrequency Electromagnetic Radiation and the Neuroprotective Effects of Aerobic Exercise in Rats: A Randomized Control Trial

BACKGROUND

The present study determined whether 4 weeks of moderate aerobic exercise improves antioxidant capacity on the brain of rats against oxidative stress caused by radiofrequency electromagnetic radiation emitted from cell phones.

METHODS

Responses of malondialdehyde, catalase, glutathione peroxidase, and superoxide dismutase, as well as the number of hippocampal dead cells, were examined. Male Wistar rats (10-12 wk old) were randomly assigned to 1 of 4 groups (N = 8): (1) moderate aerobic exercise (EXE) (2 × 15-30 min at 1215 m/min speed with 5 min of active recovery between sets), (2) exposure to 900/1800 MHz radiofrequency electromagnetic waves 3 hours per day (RAD), (3) EXE + RAD, and (4) exposure to an experimental phone without battery.

RESULTS

Following the exposure, the number of the hippocampal dead cells was significantly higher in group RAD compared with groups EXE, EXE + RAD, and control group. Malondialdehyde concentration in group RAD was significantly higher than that of groups EXE, EXE + RAD, and control group. Also, the activity of catalase, glutathione peroxidase, and superoxide dismutase in groups EXE, EXE + RAD, and control group was significantly higher compared with those of the exposure group.

CONCLUSION

This study demonstrated that moderate aerobic exercise enhances hippocampal antioxidant capacity against oxidative challenge in the form of radiofrequency electromagnetic waves.

MedXercise: a promising strategy to promote remyelination

Multiple sclerosis is an inflammatory and demyelinating disease of the central nervous system. While remyelination facilitates functional recovery in animal models, it is limited in people with multiple sclerosis. Thus, multiple strategies have been put forth to promote remyelination, including exercise and medication. Exercise promotes the release of growth factors and induces protein-level changes, while remyelinating medications act through a variety of mechanisms to promote oligodendrocyte maturation within the lesion. In animal models, the combination of medication and exercise (Medication + eXercise = MedXercise) has an additive effect on remyelination and other pathological features of multiple sclerosis. In this review, we highlight the existing literature on the effects of exercise and medication on remyelination both independently and in combination.

Neuroplastic Effect of Exercise Through Astrocytes Activation and Cellular Crosstalk

Physical exercise is an effective therapy for neurorehabilitation. Exercise has been shown to induce remodeling and proliferation of astrocyte. Astrocytes potentially affect the recruitment and function of neurons; they could intensify responses of neurons and bring more neurons for the process of neuroplasticity. Interactions between astrocytes, microglia and neurons modulate neuroplasticity and, subsequently, neural circuit function. These cellular interactions promote the number and function of synapses, neurogenesis, and cerebrovascular remodeling. However, the roles and crosstalk of astrocytes with neurons and microglia and any subsequent neuroplastic effects have not been studied extensively in exercise-induced settings. This article discusses the impact of physical exercise on astrocyte proliferation and highlights the interplay between astrocytes, microglia and neurons. The crosstalk between these cells may enhance neuroplasticity, leading to the neuroplastic effects of exercise.

The immunological influence of physical exercise on TBI-induced pathophysiology: Crosstalk between the spleen, gut, and brain

Traumatic brain injury (TBI) is a non-degenerative and non-congenital insult to the brain and is recognized as a global public health problem, with a high incidence of neurological disorders. Despite the causal relationship not being entirely known, it has been suggested that multiorgan inflammatory response involving the autonomic nervous system and the spleen-gut brain axis dysfunction exacerbate the TBI pathogenesis in the brain. Thus, applying new therapeutic tools, such as physical exercise, have been described in the literature to act on the immune modulation induced by brain injuries. However, there are caveats to consider when interpreting the effects of physical exercise on this neurological injury. Given the above, this review will highlight the main findings of the literature involving peripheral immune responses in TBI-induced neurological damage and how changes in the cellular metabolism of the spleen-gut brain axis elicited by different protocols of physical exercise alter the pathophysiology induced by this neurological injury.

Comparison of intrinsic exercise capacity and response to acute exercise in ICR (Institute of Cancer Research) mice derived from three different lineages

BACKGROUND

As a laboratory animal resource, the ICR mouse is commonly used in a variety of research fields. However, information on differences in exercise-related characteristics in ICR mice derived from different lineages and the underlying mechanisms remains to be elucidated. In this study, we investigated the intrinsic exercise capacity and a magnitude of response to acute exercise, and sought to identify mechanisms contributing to difference in Korl:ICR (a novel ICR lineage recently established by the National Institute of Food and Drug Safety Evaluation, Korea) and two commercialized ICR lineages derived from different origins (viz., A:ICR mouse from Orient Bio Com, the United States, and B:ICR mouse from Japan SLC Inc., Japan).

RESULTS

Results showed that despite no significant difference in body weight and weight-proportioned tissue mass of heart and skeletal muscles among groups, the relatively low intrinsic exercise capacity and exaggerated response to acute exercise were identified in B:ICR comparted with Korl:ICR and A:ICR, as reflected by total work and lactate threshold (LT). Also, the mitochondrial efficiency expressed as the complex 1 and complex 1 + 2 respiratory control ratio (RCR) values for cardiac mitochondrial O₂ consumption in B:ICR was significantly lower than that in Korl:ICR with higher level of state 2 respiration by glutamate/malate and UCP3 expression in cardiac muscle.

CONCLUSIONS

Taken together, these results indicate that the intrinsic exercise capacity of ICR mouse varies according to lineages, suggesting the role of cardiac mitochondrial coupling efficiency as a possible mechanism that might contribute to differences in the intrinsic exercise capacity and magnitude of response to exercise.

Exercise-linked consequences on epilepsy

OBJECTIVE

Epilepsy is a brain disorder that leads to seizures and neurobiological, cognitive, psychological, and social consequences. Physical inactivity can contribute to worse epilepsy pathophysiology. Here, we review how physical exercise affects epilepsy physiopathology.

METHODS

An extensive literature search was performed and the mechanisms of physical exercise on epilepsy were discussed. The search was conducted in Scopus and PubMed. Articles with relevant information were included. Only studies written in English were considered.

RESULTS

The regular practice of physical exercise can be beneficial for individuals with neurodegenerative diseases, such as epilepsy by decreasing the production of pro-inflammatory and stress biomarkers, increasing socialization, and reducing the incidence of epileptic seizures. Physical exercise is also capable of reducing the symptoms of depression and anxiety in epilepsy. Physical exercise can also improve cognitive function in epilepsy. The regular practice of physical exercise enhances the levels of brain-derived neuro factor (BDNF) in the hippocampi, induces neurogenesis, inhibits oxidative stress and reactive gliosis, avoids cognitive impairment, and stimulates the production of dopamine in the epileptic brain.

CONCLUSION

Physical exercise is an excellent non-pharmacological tool that can be used in the treatment of epilepsy.

Neuroinflammation in Alzheimer's Disease

Alzheimer’s disease (AD) is a neurodegenerative disease associated with human aging. Ten percent of individuals over 65 years have AD and its prevalence continues to rise with increasing age. There are currently no effective disease modifying treatments for AD, resulting in increasingly large socioeconomic and personal costs. Increasing age is associated with an increase in low-grade chronic inflammation (inflammaging) that may contribute to the neurodegenerative process in AD. Although the exact mechanisms remain unclear, aberrant elevation of reactive oxygen and nitrogen species (RONS) levels from several endogenous and exogenous processes in the brain may not only affect cell signaling, but also trigger cellular senescence, inflammation, and pyroptosis. Moreover, a compromised immune privilege of the brain that allows the infiltration of peripheral immune cells and infectious agents may play a role. Additionally, meta-inflammation as well as gut microbiota dysbiosis may drive the neuroinflammatory process. Considering that inflammatory/immune pathways are dysregulated in parallel with cognitive dysfunction in AD, elucidating the relationship between the central nervous system and the immune system may facilitate the development of a safe and effective therapy for AD. We discuss some current ideas on processes in inflammaging that appear to drive the neurodegenerative process in AD and summarize details on a few immunomodulatory strategies being developed to selectively target the detrimental aspects of neuroinflammation without affecting defense mechanisms against pathogens and tissue damage.

Preventive and Therapeutic Potential of Physical Exercise in Neurodegenerative Diseases

Significance: The prevalence and incidence of age-related neurodegenerative diseases (NDDs) tend to increase along with the enhanced average of the world life expectancy. NDDs are a major cause of morbidity and disability, affecting the health care, social and economic systems with a significant impact. Critical Issues and Recent Advances: Despite the worldwide burden of NDDs and the ongoing research efforts to increase the underlying molecular mechanisms involved in NDD pathophysiologies, pharmacological therapies have been presenting merely narrow benefits. On the contrary, absent of detrimental side effects but growing merits, regular physical exercise (PE) has been considered a prone pleiotropic nonpharmacological alternative able to modulate brain structure and function, thereby stimulating a healthier and "fitness" neurological phenotype. Future Directions: This review summarizes the state of the art of some peripheral and central-related mechanisms that underlie the impact of PE on brain plasticity as well as its relevance for the prevention and/or treatment of NDDs. Nevertheless, further studies are needed to better clarify the molecular signaling pathways associated with muscle contractions-related myokines release and its plausible positive effects in the brain. In addition, particular focus of research should address the role of PE in the modulation of mitochondrial metabolism and oxidative stress in the context of NDDs.

Physical Activity and Redox Balance in the Elderly: Signal Transduction Mechanisms

Reactive Oxygen Species (ROS) are molecules naturally produced by cells. If their levels are too high, the cellular antioxidant machinery intervenes to bring back their quantity to physiological conditions. Since aging often induces malfunctioning in this machinery, ROS are considered an effective cause of age-associated diseases. Exercise stimulates ROS production on one side, and the antioxidant systems on the other side. The effects of exercise on oxidative stress markers have been shown in blood, vascular tissue, brain, cardiac and skeletal muscle, both in young and aged people. However, the intensity and volume of exercise and the individual subject characteristics are important to envisage future strategies to adequately personalize the balance of the oxidant/antioxidant environment. Here, we reviewed the literature that deals with the effects of physical activity on redox balance in young and aged people, with insights into the molecular mechanisms involved. Although many molecular pathways are involved, we are still far from a comprehensive view of the mechanisms that stand behind the effects of physical activity during aging. Although we believe that future precision medicine will be able to transform exercise administration from wellness to targeted prevention, as yet we admit that the topic is still in its infancy.

Apolipoprotein E Polymorphism and Oxidative Stress in Human Peripheral Blood Cells: Can Physical Activity Reactivate the Proteasome System through Epigenetic Mechanisms?

Alzheimer's disease (AD) is characterized by proteasome activity impairment, oxidative stress, and epigenetic changes, resulting in β-amyloid (Aβ) production/degradation imbalance. Apolipoprotein E (ApoE) is implicated in Aβ clearance, and particularly, the ApoE ε4 isoform predisposes to AD development. Regular physical activity is known to reduce AD progression. However, the impact of ApoE polymorphism and physical exercise on Aβ production and proteasome system activity has never been investigated in human peripheral blood cells, particularly in erythrocytes, an emerging peripheral model used to study biochemical alteration. Therefore, the influence of ApoE polymorphism on the antioxidant defences, amyloid accumulation, and proteasome activity was here evaluated in human peripheral blood cells depending on physical activity, to assess putative peripheral biomarkers for AD and candidate targets that could be modulated by lifestyle. Healthy subjects were enrolled and classified based on the ApoE polymorphism (by the restriction fragment length polymorphism technique) and physical activity level (Borg scale) and grouped into ApoE ε4/non-ε4 carriers and active/non-active subjects. The plasma antioxidant capability (AOC), the erythrocyte Aβ production/accumulation, and the nuclear factor erythroid 2-related factor 2 (Nrf2) mediated proteasome functionality were evaluated in all groups by the chromatographic and immunoenzymatic assay, respectively. Moreover, epigenetic mechanisms were investigated considering the expression of histone deacetylase 6, employing a competitive ELISA, and the modulation of two key miRNAs (miR-153-3p and miR-195-5p), through the miRNeasy Serum/Plasma Mini Kit. ApoE ε4 subjects showed a reduction in plasma AOC and an increase in the Nrf2 blocker, miR-153-3p, contributing to an enhancement of the erythrocyte concentration of Aβ. Physical exercise increased plasma AOC and reduced the amount of Aβ and its precursor, involving a reduced miR-153-3p expression and a miR-195-5p enhancement. Our data highlight the impact of the ApoE genotype on the amyloidogenic pathway and the proteasome system, suggesting the positive impact of physical exercise, also through epigenetic mechanisms.

Regulation of neuronal bioenergetics as a therapeutic strategy in neurodegenerative diseases

Neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis are a heterogeneous group of debilitating disorders with multifactorial etiologies and pathogeneses that manifest distinct molecular mechanisms and clinical manifestations with abnormal protein dynamics and impaired bioenergetics. Mitochondrial dysfunction is emerging as an important feature in the etiopathogenesis of these age-related neurodegenerative diseases. The prevalence and incidence of these diseases is on the rise with the increasing global population and average lifespan. Although many therapeutic approaches have been tested, there are currently no effective treatment routes for the prevention or cure of these diseases. We present the current status of our knowledge and understanding of the involvement of mitochondrial dysfunction in these diseases and highlight recent advances in novel therapeutic strategies targeting neuronal bioenergetics as potential approach for treating these diseases.

Inflammaging, hormesis and the rationale for anti-aging strategies

We propose in this review that hormesis, a concept profoundly and systematically addressed by Mark Mattson, has to be considered a sort of comprehensive "contact point" capable of unifying several conceptualizations of the aging process, including those focused on the stress response, oxidative stress and chronic inflammation/inflammaging. A major strength of hormesis and inflammaging is that they have a strong evolutionary basis. Moreover, both hormesis and inflammaging frame the aging process within a lifelong perspective of adaptation to different types of stresses. Such adaptation perspective also suggests that the aging process is malleable, and predicts that effective anti-aging strategies should mimic what evolution did in the course of million years and that we have to learn how to exploit the great potential inherent in the hormetic/inflammatory responses. To this regard, new topics such as the production of mitokines to cope with mitochondrial dysfunction are emerging as possible anti-aging target. This approach opens theoretically the door to the possibility of modulating the individual aging rate and trajectory by adopting the most effective scientifically-based lifestyle regarding fundamentally nutrition and physical activity. In this scenario Mark Mattson's lesson and personal example will permanently enlighten the aging field and the quest for a healthy aging and longevity.

Neuroprotective Potential of Verbascoside Isolated from Acanthus mollis L. Leaves through Its Enzymatic Inhibition and Free Radical Scavenging Ability

The phenomenon of today’s ageing population has increased interest in the search for new active substances that delay the onset and development of neurodegenerative diseases. In this respect, the search for natural compounds, mainly phenolic compounds, with neuroprotective activity has become the focus of growing interest. Verbascoside is a phenylethanoid that has already presented several pharmacological activities. The purpose of this study is to isolate and identify verbascoside from Acanthus mollis leaves. Consequently, its neuroprotective ability through enzymatic inhibition and free radical scavenging ability has been analyzed both in vitro and in cell culture assays. The antioxidant capacity of verbascoside was evaluated in vitro through total antioxidant capacity, DPPH^•, ^•OH, and O₂^•—scavenging activity assays. The effect of verbascoside on intracellular reactive oxygen species (ROS) levels of HepG2 and SH-SY5Y cell lines was studied in normal culture and under induced oxidative stress. The inhibitory ability of the phenylethanoid against several enzymes implied in neurodegenerative diseases (tyrosinase, MAO-A, and AChE) was analyzed in vitro. Verbascoside neuroprotective activity is at least in part related to its free radical scavenging ability. The effect of verbascoside on ROS production suggests its potential in the prevention of harmful cell redox changes and in boosting neuroprotection.

The Effect of Endurance Training on Brain-Derived Neurotrophic Factor and Inflammatory Markers in Healthy People and Parkinson's Disease. A Narrative Review

Background: One purpose of the training conducted by people is to lose bodyweight and improve their physical condition. It is well-known that endurance training provides many positive changes in the body, not only those associated with current beauty standards. It also promotes biochemical changes such as a decreased inflammatory status, memory improvements through increased brain-derived neurotrophic factor levels, and reduced stress hormone levels. The positive effects of training may provide a novel solution for people with Parkinson's disease, as a way to reduce the inflammatory status and decrease neurodegeneration through stimulation of neuroplasticity and improved motor conditions. Aim: This narrative review aims to focus on the relationship between an acute bout of endurance exercise, endurance training (continuous and interval), brain-derived neurotrophic factor and inflammatory status in the three subject groups (young adults, older adult, and patients with Parkinson's disease), and to review the current state of knowledge about the possible causes of the differences in brain-derived neurotrophic factor and inflammatory status response to a bout of endurance exercise and endurance training. Furthermore, short practical recommendations for PD patients were formulated for improving the efficacy of the training process during rehabilitation. Methods: A narrative review was performed following an electronic search of the database PubMed/Medline and Web of Science for English-language articles between January 2010 and January 2020. Results: Analysis of the available publications with partial results revealed (1) a possible connection between the brain-derived neurotrophic factor level and inflammatory status, and (2) a more beneficial influence of endurance training compared with acute bouts of endurance exercise. Conclusion: Despite the lack of direct evidence, the results from studies show that endurance training may have a positive effect on inflammatory status and brain-derived neurotrophic factor levels. Introducing endurance training as part of the rehabilitation in Parkinson's disease might provide benefits for patients in addition to pharmacological therapy supplementation.

The effect of curcumin supplementation on recovery following exercise-induced muscle damage and delayed-onset muscle soreness: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

curcumin consumption may have a protective effect against exercise-induced muscle damage (EIMD) through stabilization of the cell membrane via inhibition of free radical formation. Evidence supporting a protective role of curcumin after physical activity induced muscle injury in humans, however, it is inconsistent.

METHODS

Medline, Scopus, and Google scholar were systematically searched up to May 2020. The Cochrane Collaboration tool for assessing the risk of bias was used for assessing the quality of studies. Random effects model, weighted mean difference (WMD), and 95% confidence interval (CI) were used for estimating the overall effect. Between-study heterogeneity was assessed using the chi-squared and I² statistic.

RESULTS

The results revealed a significant effect of curcumin supplementation on reducing creatine kinase (CK) (weighted mean difference [WMD] = -48.54 IU.L^-1 ; 95% CI: -80.667, -16.420; p = .003) and muscle soreness index decrease (WMD = -0.476; 95% CI: -0.750, -0.202; p = .001). Moreover, a subgroup analysis resulted in a significant decrease in CK concentrations and muscle soreness index, according to follow-ups after exercise, dose of curcumin, duration of studies, exercise type, train status and study design.

CONCLUSIONS

The current evidence revealed a efficacy of curcumin in reducing CK serum levels and muscle soreness index among adults. Therefore, curcumin may be known as a priority EIMD recovery agent in interventions.

Relationships between Mitochondrial Dysfunction and Neurotransmission Failure in Alzheimer's Disease

Besides extracellular deposition of amyloid beta and formation of phosphorylated tau in the brains of patients with Alzheimer's disease (AD), the pathogenesis of AD is also thought to involve mitochondrial dysfunctions and altered neurotransmission systems. However, none of these components can describe the diverse cognitive, behavioural, and psychiatric symptoms of AD without the pathologies interacting with one another. The purpose of this review is to understand the relationships between mitochondrial and neurotransmission dysfunctions in terms of (1) how mitochondrial alterations affect cholinergic and monoaminergic systems via disruption of energy metabolism, oxidative stress, and apoptosis; and (2) how different neurotransmission systems drive mitochondrial dysfunction via increasing amyloid beta internalisation, oxidative stress, disruption of mitochondrial permeabilisation, and mitochondrial trafficking. All these interactions are separately discussed in terms of neurotransmission systems. The association of mitochondrial dysfunctions with alterations in dopamine, norepinephrine, and histamine is the prospective goal in this research field. By unfolding the complex interactions surrounding mitochondrial dysfunction in AD, we can better develop potential treatments to delay, prevent, or cure this devastating disease.