Molecular Mechanisms Underlying the Beneficial Effects of Exercise on Brain Function and Neurological Disorders

Can exercise benefits be harnessed with drugs? A new way to combat neurodegenerative diseases by boosting neurogenesis

Adult hippocampal neurogenesis (AHN) is affected by multiple factors, such as enriched environment, exercise, ageing, and neurodegenerative disorders. Neurodegenerative disorders can impair AHN, leading to progressive neuronal loss and cognitive decline. Compelling evidence suggests that individuals engaged in regular exercise exhibit higher production of proteins that are essential for AHN and memory. Interestingly, specific molecules that mediate the effects of exercise have shown effectiveness in promoting AHN and cognition in different transgenic animal models. Despite these advancements, the precise mechanisms by which exercise mimetics induce AHN remain partially understood. Recently, some novel exercise molecules have been tested and the underlying mechanisms have been proposed, involving intercommunications between multiple organs such as muscle-brain crosstalk, liver-brain crosstalk, and gut-brain crosstalk. In this review, we will discuss the current evidence regarding the effects and potential mechanisms of exercise mimetics on AHN and cognition in various neurological disorders. Opportunities, challenges, and future directions in this research field are also discussed.

The protective effect of biotin supplementation and swimming training on cognitive impairment and mental symptoms in a rat model of Alzheimer's disease: A behavioral, biochemical, and histological study

Vitamin B (Vit B) plays a regulatory role in cognitive memory and learning. We examined the biochemical and behavioral effects of biotin supplementation (BS) and swimming training (ST) on Alzheimer's disease (AD), the most common type of dementia, in male rats. Sixty rats were randomly assigned to six groups: control, sham (receiving phosphate-buffered saline), AD (receiving a single injection of Aβ into the lateral ventricle), ST (for 28 days and before Aβ injection), and BS (receiving BS through oral gavage for 28 days before Aβ injection). The treatments were continued until the end of the behavioral tests. Learning and memory functions were investigated through the Morris water maze (MWM) and depression and anxiety-like behaviors were tested by elevated plus-maze (EPM) and forced swimming tests. In addition, oxidative stress biomarkers, such as total thiol groups (TTG) and malondialdehyde (MDA) in serum were assessed and histological studies were performed using brain tissues. In the AD group, Aβ increased the distance traveled and escape latency in the MWM, but co-administration of BS and ST attenuated the results of the MWM, EPM, and FST tests. Furthermore, BS decreased the litigious biochemical effects of Aβ by enhancing the levels of TTG, in addition to reducing serum MDA levels. The use of BS as a potent antioxidant improved Aβ-induced memory impairment. It attenuated oxidative stress biomarkers in the brain (number of Aβ plaques) and serum of AD rats. We provide evidence for the use of BS in neurodegenerative disorders, such as AD, to elucidate the possible mechanisms.

Exploring the neuroprotective role of physical activity in cerebral small vessel disease

Cerebral small vessel disease (cSVD) is a common neurological finding characterized by abnormalities of the small blood vessels in the brain. Previous research has established a strong connection between cSVD and stroke, as well as neurodegenerative disorders, notably Alzheimer's disease (AD) and other dementias. As the search for effective interventions continues, physical activity (PA) has emerged as a potential preventative and therapeutic avenue. This review synthesizes the human and animal literature on the influence of PA on cSVD, highlighting the importance of determining optimal exercise protocols, considering aspects such as intensity, duration, timing, and exercise type. Furthermore, the necessity of widening the age bracket in research samples is discussed, ensuring a holistic understanding of the interventions across varying pathological stages of the disease. The review also suggests the potential of exploring diverse biomarkers and risk profiles associated with clinically significant outcomes. Moreover, we review findings demonstrating the beneficial effects of PA in various rodent models of cSVD, which have uncovered numerous mechanisms of neuroprotection, including increases in neuroplasticity and integrity of the vasculature and white matter; decreases in inflammation, oxidative stress, and mitochondrial dysfunction; and alterations in amyloid processing and neurotransmitter signaling. In conclusion, this review highlights the potential of physical activity as a preventive strategy for addressing cSVD, offering insights into the need for refining exercise parameters, diversifying research populations, and exploring novel biomarkers, while shedding light on the intricate mechanisms through which exercise confers neuroprotection in both humans and animal models.

PEAK Mood, Mind, and Marks: a pilot study of an intervention to support university students' mental and cognitive health through physical exercise

Introduction

Regular exercise has the potential to enhance university students' mental and cognitive health. The PEAK Mood, Mind and Marks program (i.e., PEAK) is a neuroscience-informed intervention developed using the Behaviour Change Wheel to support students to exercise three or more times per week to benefit their mental and cognitive health. This pilot study assessed the impact of PEAK on exercise, mental and cognitive health, and implementation outcomes.

Methods

PEAK was delivered to 115 undergraduate university students throughout a 12-week university semester. The primary outcome was weekly exercise frequency. Secondary outcomes were: time spent engaged in moderate-vigorous exercise, sedentary behaviour and perceived mental health and cognitive health. All were measured via online self-report questionnaires. Qualitative interviews with 15 students investigated influences on engagement, the acceptability and appropriateness of PEAK, and its mechanisms of behaviour change. Paired t-tests, Wilcoxon Signed-Rank tests and template analysis were used to analyse quantitative and qualitative data, respectively.

Results

On average, 48.4% of students engaged in the recommended frequency of three or more exercise sessions per week. This proportion decreased towards the end of PEAK. Sedentary behaviour significantly decreased from baseline to end-point, and moderate-vigorous exercise significantly increased among students' who were non-exercisers. Mental wellbeing, stress, loneliness, and sense of belonging to the university significantly improved. There were no significant changes in psychological distress. Concentration, memory, and productivity significantly improved. Sixty-eight percent of students remained engaged in one or more components of PEAK at end-point. Qualitative data indicated students found PEAK to be acceptable and appropriate, and that it improved aspects of their capability, opportunity, and motivation to exercise.

Conclusions

Students are receptive to an exercise-based program to support their mental and cognitive health. Students exercise frequency decreased; however, these figures are likely a conservative estimate of students exercise engagement. Students valued the neuroscience-informed approach to motivational and educational content and that the program's goals aligned with their academic goals. Students identified numerous areas PEAK's content and implementation can be optimised, including use of a single digital delivery platform, more opportunities to connect with peers and to expand the content's cultural inclusivity.

Association Between Physical Activity and Mental Health in Health Professionals in the Context of the Pandemic: A Study in Southern Brazil

OBJECTIVE

The aim of the study was to verify the association between physical activity (PA) and mental health among health professionals in southern Brazil.

METHODS

This is a cross-sectional study with 101 workers during the COVID-19 pandemic. Mental health and PA were assessed using the questionnaires. The association of PA with stress was tested by linear regression, and anxiety and depressive symptoms by Poisson regression.

RESULTS

The stress was inversely associated with individuals who performed some PA (β: -3.53;95% CI: -6.63;-0.44) and who met the PA recommendations (active) (β: -6.84;95% CI: -12.44;-1.24). Workers who performed some PA (PR: 0.76;95% CI: 0.67;0.86) and were active (PR: 0.75;95% CI: 0.60;0.93) were less likely to have severe symptoms of anxiety. For depression, workers who performed some PA (PR: 0.81;95% CI: 0.71;0.92) and were active (PR: 0.69;95% CI: 0.54;0.88), the probability was also smaller.

CONCLUSIONS

The practice of PA was inversely associated with symptoms of stress, depression, and anxiety.

Ageing, Cognitive Decline, and Effects of Physical Exercise: Complexities, and Considerations from Animal Models

In our ageing global population, the cognitive decline associated with dementia and neurodegenerative diseases represents a major healthcare problem. To date, there are no effective treatments for age-related cognitive impairment, thus preventative strategies are urgently required. Physical exercise is gaining traction as a non-pharmacological approach to promote brain health. Adult hippocampal neurogenesis (AHN), a unique form of brain plasticity which is necessary for certain cognitive functions declines with age and is enhanced in response to exercise. Accumulating evidence from research in rodents suggests that physical exercise has beneficial effects on cognition through its proneurogenic capabilities. Given ethical and technical limitations in human studies, preclinical research in rodents is crucial for a better understanding of such exercise-induced brain and behavioural changes. In this review, exercise paradigms used in preclinical research are compared. We provide an overview of the effects of different exercise paradigms on age-related cognitive decline from middle-age until older-age. We discuss the relationship between the age-related decrease in AHN and the potential impact of exercise on mitigating this decline. We highlight the emerging literature on the impact of exercise on gut microbiota during ageing and consider the role of the gut-brain axis as a future possible strategy to optimize exercise-enhanced cognitive function. Finally, we propose a guideline for designing optimal exercise protocols in rodent studies, which would inform clinical research and contribute to developing preventative strategies for age-related cognitive decline.

Does the liver facilitate aging-related cognitive impairment: Conversation between liver and brain during exercise?

Liver, an important regulator of metabolic homeostasis, is critical for healthy brain function. In particular, age-related neurodegenerative diseases seriously reduce the quality of life for the elderly. As population aging progresses rapidly, unraveling the mechanisms that effectively delay aging has become critical. Appropriate exercise is reported to improve aging-related cognitive impairment. Whereas current studies focused on exploring the effect of exercise on the aging brain itself, ignoring the persistent effects of peripheral organs on the brain through the blood circulation. The aim of this paper is to summarize the communication and aging processes of the liver and brain and to emphasize the metabolic mechanisms of the liver-brain axis about exercise ameliorating aging-related neurodegenerative diseases. A comprehensive understanding of the potential mechanisms about exercise ameliorating aging is critical for improving adaptation to age-related brain changes and formulating effective interventions against age-related cognitive decline.

Physical activity and school adaptation among Chinese junior high school students: chain mediation of resilience and coping styles

Background

As a crucial juncture in students' educational journey, junior high school presents challenges that profoundly influence well-being and academic performance. Physical activity emerges as a pivotal factor shaping the holistic development of junior high school students. Beyond its recognized impact on physical and mental health, engaging in regular physical activity proves effective in augmenting students' adaptability to school life. Despite its importance, the mechanisms through which physical activity influences school adaptation in junior high school students remain understudied in academic research.

Objective

In exploring the potential mechanisms, this study aims to validate the mediating roles of resilience and coping styles by examining the association between physical activity and school adaptation among junior high school students.

Methods

This study employed cross-sectional survey approach among junior high school students in China. Through the convenience sampling, 1,488 participants aged from 12 to 16 years old (Average age = 13.59, SD = 1.017) from two Junior high schools in Changsha City, Hunan Province were recruited to complete the Physical Activity Scale, School Adaptation Questionnaire for Junior High School Students, Resilience Scale for Adolescents, and Simple Coping Styles Questionnaire. For data analysis, the SPSS 26.0 and Amos 26.0 were used for statistical processing.

Results

The results showed that physical activity exhibited a significant correlation with school adaptation (r = 0.656, p < 0.001). Resilience, positive coping style and negative coping style played partial mediating roles between physical activity and school adaptation, with the effect size were 0.229, 0.170, 0.171. The chain mediation effect size of resilience and positive coping style was 0.042, while the chain mediation effect size of resilience and negative coping style was 0.050.

Conclusion

Physical activity positively predicts Chinese junior high school students' school adaptation through resilience and coping styles, suggesting that junior high school students should engage in regular physical activity, so as to improve their resilience and positive coping styles, mitigating negative coping styles, thus promoting their school adaptation.

Transcriptional Expression of Histone Acetyltransferases and Deacetylases During the Recovery of Acute Exercise in Mouse Hippocampus

Protein acetylation, which is dynamically maintained by histone acetyltransferases (HATs) and deacetylases (HDACs), might play essential roles in hippocampal exercise physiology. However, whether HATs/HDACs are imbalanced during the recovery phase following acute exercise has not been determined. Groups of exercised mice with different recovery periods after acute exercise (0 h, 0.5 h, 1 h, 4 h, 7 h, and 24 h) were constructed, and a group of sham-exercised mice was used as the control. The mRNA levels of HATs and HDACs were detected via real-time quantitative polymerase chain reaction. Lysine acetylation on the total proteins and some specific locations on histones were detected via western blotting, as were various acylation modifications on the total proteins. Except for four unaffected genes (Hdac4, Ncoa1, Ncoa2, and Sirt1), the mRNA expression trajectories of 21 other HATs or HDACs affected by exercise could be categorized into three clusters. The genes in Cluster 1 increased quickly following exercise, with a peak at 0.5 h and/or 1 h, and remained at high levels until 24 h. Cluster 2 genes presented a gradual increase with a delayed peak at 4 h or 7 h postexercise before returning to baseline. The expression of Cluster 3 genes decreased at 0.5 h and/or 1 h, with some returning to overexpression (Hdac1 and Sirt3). Although most HATs were upregulated and half of the affected HDACs were downregulated at 0.5 h postexercise, the global or residue-specific histone acetylation levels were unchanged. In contrast, the levels of several metabolism-related acylation products of total proteins, including acetylation, succinylation, 2-hydroxyisobutyryllysine, β-hydroxybutyryllysine, and lactylation, decreased and mainly occurred on nonhistones immediately after exercise. During the 24-h recovery phase after acute exercise, the transcriptional trajectory of HATs or the same class of HDACs in the hippocampus exhibited heterogeneity. Although acute exercise did not affect the selected sites on histone lysine residues, it possibly incurred changes in acetylation and other acylation on nonhistone proteins.

Investigation of the involvement of platelet-activating factor in the control of hypertension by aerobic training. A randomized controlled trial

Although studies have demonstrated the effectiveness of exercise in controlling systemic arterial hypertension (SAH), the mechanisms involved in this effect are still poorly understood. Thus, this study investigated the impact of aerobic training on the relationship between platelet-activating factor (PAF) circulating levels and blood pressure in hypertensives. Seventy-seven hypertensive subjects were enrolled in this randomized controlled trial (age 66.51 ± 7.53 years, body mass 76.17 ± 14.19 kg). Participants were randomized to two groups: the intervention group (IG, n = 36), composed of hypertensive individuals submitted to an aerobic training protocol, and the control group (CG, n = 41), composed of non-exercised hypertensives. Body mass index, arterial blood pressure, quality of life, respiratory muscle strength, and functional capacity were assessed before and after 12 weeks. PAF and plasma cytokine levels were also evaluated respectively by liquid chromatography coupled with mass spectrometry and enzyme-linked immunosorbent assay. Aerobic training promoted a significant reduction in blood pressure while functional capacity, expiratory muscle strength, and quality of life, PAFC16:0 and PAFC18:1 plasma levels were increased in comparison to the CG (p < 0.05). In addition, multiple correlation analysis indicated a positive correlation [F (3.19) = 6.322; p = 0.001; R2adjusted = 0.499] between PAFC16:0 levels and expiratory muscle strength after aerobic training. Taken together, our findings indicate that PAF may be involved in the indirect mechanisms that control SAH, being mainly associated with increased respiratory muscle strength in hypertensive subjects undergoing aerobic training.

Musclin prevents depression-like behavior in male mice by activating urocortin 2 signaling in the hypothalamus

Introduction

Physical activity is recommended as an alternative treatment for depression. Myokines, which are secreted from skeletal muscles during physical activity, play an important role in the skeletal muscle-brain axis. Musclin, a newly discovered myokine, exerts physical endurance, however, the effects of musclin on emotional behaviors, such as depression, have not been evaluated. This study aimed to access the anti-depressive effect of musclin and clarify the connection between depression-like behavior and hypothalamic neuropeptides in mice.

Methods

We measured the immobility time in the forced swim (FS) test, the time spent in open arm in the elevated-plus maze (EPM) test, the mRNA levels of hypothalamic neuropeptides, and enumerated the c-Fos-positive cells in the paraventricular nucleus (PVN), arcuate nucleus (ARC), and nucleus tractus solitarii (NTS) in mice with the intraperitoneal (i.p.) administration of musclin. Next, we evaluated the effects of a selective corticotropin-releasing factor (CRF) type 1 receptor antagonist, selective CRF type 2 receptor antagonist, melanocortin receptor (MCR) agonist, and selective melanocortin 4 receptor (MC4R) agonist on changes in behaviors induced by musclin. Finally we evaluated the antidepressant effect of musclin using mice exposed to repeated water immersion (WI) stress.

Results

We found that the i.p. and i.c.v. administration of musclin decreased the immobility time and relative time in the open arms (open %) in mice and increased urocortin 2 (Ucn 2) levels but decreased proopiomelanocortin levels in the hypothalamus. The numbers of c-Fos-positive cells were increased in the PVN and NTS but decreased in the ARC of mice with i.p. administration of musclin. The c-Fos-positive cells in the PVN were also found to be Ucn 2-positive. The antidepressant and anxiogenic effects of musclin were blocked by central administration of a CRF type 2 receptor antagonist and a melanocortin 4 receptor agonist, respectively. Peripheral administration of musclin also prevented depression-like behavior and the decrease in levels of hypothalamic Ucn 2 induced by repeated WI stress.

Discussion

These data identify the antidepressant effects of musclin through the activation of central Ucn 2 signaling and suggest that musclin and Ucn 2 can be new therapeutic targets and endogenous peptides mediating the muscle-brain axis.

Mitochondrial Dysfunction in Skeletal Muscle of Rotenone-Induced Rat Model of Parkinson's Disease: SC-Nanophytosomes as Therapeutic Approach

The development of new therapeutic options for Parkinson's disease (PD) requires formulations able to mitigate both brain degeneration and motor dysfunctions. SC-Nanophytosomes, an oral mitochondria-targeted formulation developed with Codium tomentosum membrane polar lipids and elderberry anthocyanin-enriched extract, promote significant brain benefits on a rotenone-induced rat model of PD. In the present work, the effects of SC-Nanophytosome treatment on the skeletal muscle tissues are disclosed. It is unveiled that the rotenone-induced PD rat model exhibits motor disabilities and skeletal muscle tissues with deficient activity of mitochondrial complexes I and II along with small changes in antioxidant enzyme activity and skeletal muscle lipidome. SC-Nanophytosome treatment mitigates the impairment of complexes I and II activity, improving the mitochondrial respiratory chain performance at levels that surpass the control. Therefore, SC-Nanophytosome competence to overcome the PD-related motor disabilities should be also associated with its positive outcomes on skeletal muscle mitochondria. Providing a cellular environment with more reduced redox potential, SC-Nanophytosome treatment improves the skeletal muscle tissue's ability to deal with oxidative stress stimuli. The PD-related small changes on skeletal muscle lipidome were also counteracted by SC-Nanophytosome treatment. Thus, the present results reinforces the concept of SC-Nanophytosomes as a mitochondria-targeted therapy to address the neurodegeneration challenge.

Fndc5/irisin deficiency leads to dysbiosis of gut microbiota contributing to the depressive-like behaviors in mice

BACKGROUND

Depression is one of the most common mental diseases and the leading cause of disability worldwide. A dysfunctional gut microbiota-brain axis is one of the main pathological bases of depression. Irisin, an exercise-related myokine, reduces depression-like behaviors and may guide the relief of depressive symptoms by exercise. However, its underlying mechanism remains unclear.

METHODS

Fibronectin type III domain containing 5 (Fndc5)/Irisin was knocked out in male wide-type C57BL/6N mice using CRISPR-cas9. The depression and anxiety symptoms were examined in irisin knockout and control mice with or without chronic unpredictable mild stress by sucrose preference test (SPT), forced swimming test (FST), and tail suspension test (TST). Fecal microbiota was assessed by 16S rRNA sequencing and microbiota-related metabolites using liquid chromatography with tandem mass spectrometry. Differential metabolites were analyzed with the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses.

RESULTS

The knockout mice showed anxiety- and depression-like behaviors and altered diversity and richness of gut microbiota. At the phylum level, these mice had decreased Firmicutes and increased Bacteroidota populations, while at the genus level, they exhibited a low relative abundance of Lactobacillus and Bifidobacterium. Moreover, knocking out of Irisin gene in these mice significantly reduced N-desmethyl-mifepristone (RU 42633) and elevated (-)-stercobilin levels. The KEGG results showed that the microbiota-related metabolites affected by irisin mainly clustered into arginine and proline metabolism and affected the mechanistic target of rapamycin kinase (mTOR) signaling pathway.

CONCLUSION

Our findings show that Fndc5/irisin deficiency causes depression in mice by inducing dysbiosis of gut microbiota and changes in microbiota-related metabolites.

Investigation of the protective effect of long-term exercise on molecular pathways and behaviours in scopolamine induced alzheimer's disease-like condition

Despite research, the role of exercise in treatment and prevention of neurodegenerative diseases remains unclear. Our study, investigated that protective effect of treadmill exercise on molecular pathways and cognitive behaviours in a scopolamine-induced model of Alzheimer's disease. For that purpose, male Balb/c mice subjected to exercise for 12 weeks. During the last 4 weeks of exercise, mice were given an injection of scopolamine (2 mg/kg). Following injection, open field test and Morris water maze test were used to assess emotional-cognitive behaviour. Hippocampus and prefrontal cortex of mice were isolated, and levels of BDNF, TrkB, and p-GSK3ßSer389 were assessed by western blotting, and levels of APP and Aß-40 were analysed by immunohistochemistry. In our study, scopolamine administration increased anxiety-like behaviour in open field test, while negatively affecting spatial learning and memory in Morris water maze test. We found that exercise had a protective effect against cognitive and emotional decline. Scopolamine decreased levels of p-GSK3ßSer389, BDNF in hippocampus and prefrontal cortex.Whereas TrkB decreased in hippocampus and increased in prefrontal cortex. There was an increase in p-GSK3ßSer389, BDNF, TrkB in the hippocampus, and p-GSK3ßSer389, BDNF in the prefrontal cortex in the exercise + scopolamine group. Immunohistochemical analysis showed that scopolamine administration increased APP and Aß-40 in hippocampus and prefrontal cortex in neuronal and perineuronal areas whereas Aß-40 and APP were reduced in exercise + scopolamine groups. In conclusion, long-term exercise may have a protective effect against scopolamine-induced impairments in cognitive-emotional behaviour. It can be suggested that this protective effect is mediated by increased BDNF levels and GSK3ßSer389 phosphorylation.

Examining the Interaction between Exercise, Gut Microbiota, and Neurodegeneration: Future Research Directions

Physical activity has been demonstrated to have a significant impact on gut microbial diversity and function. Emerging research has revealed certain aspects of the complex interactions between the gut, exercise, microbiota, and neurodegenerative diseases, suggesting that changes in gut microbial diversity and metabolic function may have an impact on the onset and progression of neurological conditions. This study aimed to review the current literature from several databases until 1 June 2023 (PubMed/MEDLINE, Web of Science, and Google Scholar) on the interplay between the gut, physical exercise, microbiota, and neurodegeneration. We summarized the roles of exercise and gut microbiota on neurodegeneration and identified the ways in which these are all connected. The gut-brain axis is a complex and multifaceted network that has gained considerable attention in recent years. Research indicates that gut microbiota plays vital roles in metabolic shifts during physiological or pathophysiological conditions in neurodegenerative diseases; therefore, they are closely related to maintaining overall health and well-being. Similarly, exercise has shown positive effects on brain health and cognitive function, which may reduce/delay the onset of severe neurological disorders. Exercise has been associated with various neurochemical changes, including alterations in cortisol levels, increased production of endorphins, endocannabinoids like anandamide, as well as higher levels of serotonin and dopamine. These changes have been linked to mood improvements, enhanced sleep quality, better motor control, and cognitive enhancements resulting from exercise-induced effects. However, further clinical research is necessary to evaluate changes in bacteria taxa along with age- and sex-based differences.

Mind body exercise improves cognitive function more than aerobic- and resistance exercise in healthy adults aged 55 years and older - an umbrella review

Exercise is often cited as a major factor contributing to improved cognitive functioning. As a result, the relationship between exercise and cognition has received much attention in scholarly literature. Systematic reviews and meta-analyses present varying and sometimes conflicting results about the extent to which exercise can influence cognition. The aim of this umbrella review was to summarize the effects of physical exercise on cognitive functions (global cognition, executive function, memory, attention, or processing speed) in healthy adults ≥ 55 years of age.Methods An umbrella review of systematic reviews with meta-analyses investigating the effect of exercise on cognition was performed. Databases (CINAHL, Cochrane Library, MEDLINE, PsycInfo, Scopus, and Web of Science) were searched from inception until June 2023 for reviews of randomized or non-randomised controlled trials. Full-text articles meeting the inclusion criteria were reviewed and methodological quality assessed. Overlap within included reviews was assessed using the corrected covered area method (CCA). A random effects model was used to calculate overall pooled effect size with sub-analyses for specific cognitive domains, exercise type and timing of exercise.Results Database searches identified 9227 reviews. A total of 20 met the inclusion criteria. They were based on 332 original primary studies. Overall quality of the reviews was considered moderate with most meeting 8 or more of the 16 AMSTAR 2 categories. Overall pooled effects indicated that exercise in general has a small positive effect on cognition (d = 0.22; SE = 0.04; p < 0.01). Mind-body exercise had the greatest effect with a pooled effect size of (d = 0.48; SE = 0.06; p < 0.001). Exercise had a moderate positive effect on global cognition (d = 0.43; SE = 0,11; p < 0,001) and a small positive effect on executive function, memory, attention, and processing speed. Chronic exercise was more effective than acute exercise. Variation across studies due to heterogeneity was considered very high.Conclusions Mind-body exercise has moderate positive effects on the cognitive function of people aged 55 or older. To promote healthy aging, mind-body exercise should be used over a prolonged period to complement other types of exercise. Results of this review should be used to inform the development of guidelines to promote healthy aging.Trial registration PROSPERO (CDR 42022312955).

Relationship between Serum Irisin Levels and MRI-Measured Cerebral Small Vessel Disease in Japanese Men

AIM

Irisin, an exercise-induced myokine, is a potential neurotrophic factor; however, its relationship with cerebral small vessel disease (CSVD) remains unknown. Therefore, we investigated whether serum irisin levels are associated with CSVD in healthy Japanese men.

METHODS

We analyzed data from 720 men free of stroke and participated in this observational study. Serum irisin levels were measured by enzyme-linked immunosorbent assay. CSVD was assessed on deep and subcortical white matter hyperintensities (DSWMHs), periventricular hyperintensities (PVHs), lacunar infarcts (LIs), and cerebral microbleeds (CMBs) on brain magnetic resonance imaging. We calculated the total CSVD score (ranges 0-4) to express the total CSVD burden. We computed the adjusted odds ratios (ORs), with 95% confidence intervals (CIs), of the total CSVD score and individual CSVD features using logistic regression models according to the quartiles of irisin (reference: Q1).

RESULTS

Serum irisin levels were associated with lower ORs of higher (vs. zero or lower score) total CSVD score, with the lowest risk (OR, 0.63; 95% CI, 0.41-0.97) being observed in Q3 compared to Q1 after adjustment of potential covariates. Similar results were obtained for younger adults (＜65 years). Among individual CSVD features, irisin was associated with a reduced risk of LIs in the total sample and PVHs, LIs, and CMBs in younger adults. No relationship was observed in older adults (≥ 65 years).

CONCLUSIONS

Serum irisin levels were associated with less burden of total CSVD in healthy Japanese men. Serum irisin levels were also related with a reduced risk of PVHs, LIs, and CMBs, but not DSWMHs.

Exercise for Mental Well-Being: Exploring Neurobiological Advances and Intervention Effects in Depression

Depression is a common mental disorder in which patients often experience feelings of sadness, fatigue, loss of interest, and pleasure. Exercise is a widely used intervention for managing depression, but the specific molecular mechanisms underlying its antidepressant effect are unclear. In this narrative review, we aim to synthesize current knowledge on the molecular, neural, and physiological mechanisms through which exercise exerts its antidepressant effect and discuss the various exercise interventions used for managing depression. We conducted a narrative review of the literature on the topic of exercise and depression. Our review suggests that exercise impacts peripheral tryptophan metabolism, central inflammation, and brain-derived neurotrophic factors through the peroxisome proliferator-activated receptor γ activating factor 1α (PGC-1α) in skeletal muscles. The uncarboxylated osteocalcin facilitates "bone-brain crosstalk", and exercise corrects atypical expression of brain-gut peptides, modulates cytokine production and neurotransmitter release, and regulates inflammatory pathways and microRNA expression. Aerobic exercise is recommended at frequencies of 3 to 5 times per week with medium to high intensity. Here we highlight the significant potential of exercise therapy in managing depression, supported by the molecular, neural, and physiological mechanisms underlying its antidepressant effect. Understanding the molecular pathways and neural mechanisms involved in exercise's antidepressant effect opens new avenues for developing novel therapies for managing depression.

Brain metabolism in Alzheimer's disease: biological mechanisms of exercise

Alzheimer's disease (AD) is a major subtype of neurodegenerative dementia caused by long-term interactions and accumulation of multiple adverse factors, accompanied by dysregulation of numerous intracellular signaling and molecular pathways in the brain. At the cellular and molecular levels, the neuronal cellular milieu of the AD brain exhibits metabolic abnormalities, compromised bioenergetics, impaired lipid metabolism, and reduced overall metabolic capacity, which lead to abnormal neural network activity and impaired neuroplasticity, thus accelerating the formation of extracellular senile plaques and intracellular neurofibrillary tangles. The current absence of effective pharmacological therapies for AD points to the urgent need to investigate the benefits of non-pharmacological approaches such as physical exercise. Despite the evidence that regular physical activity can improve metabolic dysfunction in the AD state, inhibit different pathophysiological molecular pathways associated with AD, influence the pathological process of AD, and exert a protective effect, there is no clear consensus on the specific biological and molecular mechanisms underlying the advantages of physical exercise. Here, we review how physical exercise improves crucial molecular pathways and biological processes associated with metabolic disorders in AD, including glucose metabolism, lipid metabolism, Aβ metabolism and transport, iron metabolism and tau pathology. How metabolic states influence brain health is also presented. A better knowledge on the neurophysiological mechanisms by which exercise improves AD metabolism can contribute to the development of novel drugs and improvement of non-pharmacological interventions.

Recent advances on the molecular mechanisms of exercise-induced improvements of cognitive dysfunction

Physical exercise is of great significance for maintaining human health. Exercise can provide varying degrees of benefits to cognitive function at all stages of life cycle. Currently, with the aging of the world's population and increase of life expectancy, cognitive dysfunction has gradually become a disease of high incidence, which is accompanied by neurodegenerative diseases in elderly individuals. Patients often exhibit memory loss, aphasia and weakening of orientation once diagnosed, and are unable to have a normal life. Cognitive dysfunction largely affects the physical and mental health, reduces the quality of life, and causes a great economic burden to the society. At present, most of the interventions are aimed to maintain the current cognitive level and delay deterioration of cognition. In contrast, exercise as a nonpharmacological therapy has great advantages in its nontoxicity, low cost and universal application. The molecular mechanisms underlying the effect of exercise on cognition are complex, and studies have been extensively centered on neural plasticity, the direct target of exercise in the brain. In addition, mitochondrial stability and energy metabolism are essential for brain status. Meanwhile, the organ-brain axis responds to exercise and induces release of cytokines related to cognition. In this review, we summarize the latest evidence on the molecular mechanisms underlying the effects of exercise on cognition, and point out directions for future research.

Chronic exercise remodels the lysine acetylome in the mouse hippocampus

Physical exercise benefits hippocampal function through various molecular mechanisms. Protein acetylation, a conserved and widespread post-translational modification, is involved in the synaptic plasticity and memory. However, whether exercise can change global acetylation and the role of acetylated proteins in the hippocampus have remained largely unknown. Herein, using healthy adult mice running for 6 weeks as exercise model and sedentary mice as control, we analyzed the hippocampal lysine acetylome and proteome by Liquid chromatography-tandem mass spectrometry. As a result, we profiled the lysine acetylation landscape for the hippocampus and identified 3,876 acetyl sites and 1,764 acetylated proteins. A total of 272 acetyl sites on 252 proteins were differentially regulated by chronic exercise, among which 18.58% acetylated proteins were annotated in mitochondria. These proteins were dominantly deacetylated and mainly associated with carbon-related metabolism, the Hippo signaling pathway, ribosomes, and protein processing. Meanwhile, 21 proteins were significantly expressed and enriched in the pathway of complement and coagulation cascades. Our findings provide a new avenue for understanding the molecular mechanisms underlying the benefits of exercise for hippocampal function and can contribute to the promotion of public health.

Effects of Strength Training on BDNF in Healthy Young Adults

The physical improvements from strength and resistance training have been known for decades, but the cognitive benefits of this type of activity are not as well-known. The aim of this review article is to provide a summary of studies presenting the effects of strength and resistance training on BDNF in healthy young adults. A systematic search of various electronic databases (PubMed, Web of Science, Science Direct and Google Scholar) was conducted in September 2022. Studies that examined associations between strength training and BDNF in healthy young adults aged 18-30 years were included. The final sample included 10 studies published between 2009 and 2020. The results of this literature review are inconclusive. Based on the results of the 10 studies, there is no clear answer as to whether strength training has positive effects on BDNF in healthy young adults.

Burnout and resilience in intensive care Nursing professionals in the face of COVID-19: A multicenter study

OBJECTIVE

to analyze the relationship between the Burnout dimensions and the work resilience of intensive care Nursing professionals in the COVID-19 pandemic in four hospitals from southern Brazil.

METHOD

this is a multicenter and cross-sectional study, composed of 153 nurses and nursing technicians of the Intensive Care Units. Sociodemographic, health and work-related questions were collected, and the Maslach Burnout Inventory and Resilience at Work Scale 20 instruments were applied. The data were submitted to descriptive analysis and to bivariate and partial correlations (network analysis).

RESULTS

work resilience presented an inverse correlation to emotional exhaustion (r=-0.545; p=0.01) and depersonalization (r=-0.419; p=0.01) and a direct one to professional achievement (r=0.680; p=0.01). The variable with the greatest influence on the correlation network was the perception of the impact of the pandemic on mental health.

CONCLUSION

resilience interferes in the emotional exhaustion and low professional achievement domains of Burnout. Emotional exhaustion is conducted through minor psychological disorders, with an impact on the workers' physical and mental health variables. The development of institutional resilience should be encouraged in order to moderate the illness.

Functional Properties of Meat in Athletes’ Performance and Recovery

Physical activity (PA) and sport play an essential role in promoting body development and maintaining optimal health status both in the short and long term. Despite the benefits, a long-lasting heavy training can promote several detrimental physiological changes, including transitory immune system malfunction, increased inflammation, and oxidative stress, which manifest as exercise-induced muscle damages (EIMDs). Meat and derived products represent a very good source of bioactive molecules such as proteins, lipids, amino acids, vitamins, and minerals. Bioactive molecules represent dietary compounds that can interact with one or more components of live tissue, resulting in a wide range of possible health consequences such as immune-modulating, antihypertensive, antimicrobial, and antioxidative activities. The health benefits of meat have been well established and have been extensively reviewed elsewhere, although a growing number of studies found a significant positive effect of meat molecules on exercise performance and recovery of muscle function. Based on the limited research, meat could be an effective post-exercise food that results in favorable muscle protein synthesis and metabolic performance.

Effects of COVID-19 on Physical Activity and Its Relationship With Mental Health in a US Community Sample: Cross-sectional, Convenience Sampling-based Online Survey

Background

COVID-19 restrictions may make it difficult for people to engage in the recommended amounts of physical activity (PA).

Objective

The influence of the COVID-19 pandemic on PA, as well as the links between PA and mental health, was investigated in this study.

Methods

Participants were recruited using convenience sampling and responded to an online survey between April 15 and July 1, 2021, with ages ranging from 18 to 24 years (n=156, 40.9% of the sample) to ≥55 years (n=28, 7.4% of the sample). To assess general psychological distress, depression, anxiety, and pandemic anxiety, a battery of mental health assessments was used. The International Physical Activity Questionnaire - Short Form was used to collect PA data from participants, who were then classified as inactive, minimally active, or highly active. Participants also indicated the locations where they performed PA before and during COVID-19.

Results

A sample of 381 individuals was included in this research. The logistic regression analysis results were interpreted as odds ratios (ORs), where an OR higher than 1 indicated a greater chance of an event occurring and an OR less than 1 implied a lower likelihood of an event occurring. Logistic regression results revealed that inactive individuals were more likely to develop psychological distress (OR 2.17, 95% CI 1.27-3.69, P=.004), depression (OR 3.81, 95% CI 1.92-7.57, P<.001), and anxiety (OR 1.86, 95% CI 0.99-3.47, P=.05) as compared to highly active individuals. Furthermore, when compared to highly active people, those who were only minimally active had a higher risk of depression (OR 2.14, 95% CI 1.05-4.33, P=.04). Wilcoxon signed-rank tests revealed that COVID-19 has a greater impact on reducing the chances of less active individuals engaging in PA outside and in public spaces. Highly active people's physical exercise locations had changed less, and their exercise frequency at home increased.

Conclusions

Programmatic and policy interventions geared particularly toward enhancing PA among those less active may be a helpful strategy for addressing the worldwide pandemic’s mental health crisis.

Cognitive and Physical Intervention in Metals’ Dysfunction and Neurodegeneration

Metals—especially iron, copper and manganese—are important elements of brain functions and development. Metal-dysregulation homeostasis is associated with brain-structure damage to the motor, cognitive and emotional systems, and leads to neurodegenerative processes. There is more and more evidence that specialized cognitive and motor exercises can enhance brain function and attenuate neurodegeneration in mechanisms, such as improving neuroplasticity by altering the synaptic structure and function in many brain regions. Psychological and physical methods of rehabilitation are now becoming increasingly important, as pharmacological treatments for movement, cognitive and emotional symptoms are limited. The present study describes physical and cognitive rehabilitation methods of patients associated with metal-induced neurotoxicity such as Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, Huntington’s disease and Wilson’s disease. In our review, we describe physical (e.g., virtual-reality environments, robotic-assists training) and psychological (cognitive training, cognitive stimulation, neuropsychological rehabilitation and cognitive-behavioral and mindfulness-based therapies) methods, significantly improving the quality of life and independence of patients associated with storage diseases. Storage diseases are a diverse group of hereditary metabolic defects characterized by the abnormal cumulation of storage material in cells. This topic is being addressed due to the fact that rehabilitation plays a vital role in the treatment of neurodegenerative diseases. Unfortunately so far there are no specific guidelines concerning physiotherapy in neurodegenerative disorders, especially in regards to duration of exercise, type of exercise and intensity, as well as frequency of exercise. This is in part due to the variety of symptoms of these diseases and the various levels of disease progression. This further proves the need for more research to be carried out on the role of exercise in neurodegenerative disorder treatment.

Recent Neurotherapeutic Strategies to Promote Healthy Brain Aging: Are we there yet?

Owing to the global exponential increase in population ageing, there is an urgent unmet need to develop reliable strategies to slow down and delay the ageing process. Age-related neurodegenerative diseases are among the main causes of morbidity and mortality in our contemporary society and represent a major socio-economic burden. There are several controversial factors that are thought to play a causal role in brain ageing which are continuously being examined in experimental models. Among them are oxidative stress and brain inflammation which are empirical to brain ageing. Although some candidate drugs have been developed which reduce the ageing phenotype, their clinical translation is limited. There are several strategies currently in development to improve brain ageing. These include strategies such as caloric restriction, ketogenic diet, promotion of cellular nicotinamide adenine dinucleotide (NAD+) levels, removal of senescent cells, 'young blood' transfusions, enhancement of adult neurogenesis, stem cell therapy, vascular risk reduction, and non-pharmacological lifestyle strategies. Several studies have shown that these strategies can not only improve brain ageing by attenuating age-related neurodegenerative disease mechanisms, but also maintain cognitive function in a variety of pre-clinical experimental murine models. However, clinical evidence is limited and many of these strategies are awaiting findings from large-scale clinical trials which are nascent in the current literature. Further studies are needed to determine their long-term efficacy and lack of adverse effects in various tissues and organs to gain a greater understanding of their potential beneficial effects on brain ageing and health span in humans.

Nutraceuticals and Physical Activity as Antidepressants: The Central Role of the Gut Microbiota

Major depressive disorder (MDD) is a common mental illness. Evidence suggests that the gut microbiota play an essential role in regulating brain functions and the pathogenesis of neuropsychiatric diseases, including MDD. There are numerous mechanisms through which the gut microbiota and brain can exchange information in a continuous, bidirectional communication. Current research emphasizes the interexchange of signals influenced by the gut microbiota that are detected and transduced in information from the gut to the nervous system involving neural, endocrine, and inflammatory mechanisms, suggesting a relationship between oxidative stress and the pathophysiology of MDD via the hyperactivation of inflammatory responses. Potential sources of inflammation in the plasma and hippocampus of depressed individuals could stem from increases in intestinal permeability. Some nutraceuticals, such as specific probiotics, namely psychobiotics, polyphenols, carotenoids, butyrate, and prebiotics, have been demonstrated to exert an antidepressant activity, but most of them need to be metabolized and activated by gut microorganisms. By inducing changes in the gut microbiota composition, physical exercise might also exert a role in alleviating depression-like symptoms. The mutual relationships among nutraceuticals, exercise, and depression will be discussed, and the potential role of the gut microbiota as a therapeutic target to treat depression will be explored.

Burnout y resiliencia en profesionales de enfermería de cuidados intensivos ante el COVID-19: estudio multicéntrico

Resumen Objetivo: analizar la relación entre las dimensiones del Burnout y la resiliencia en el trabajo de los profesionales de enfermería de cuidados intensivos durante la pandemia de COVID-19, en cuatro hospitales del sur de Brasil. Método: se trata de un estudio multicéntrico, transversal, compuesto por 153 enfermeros y técnicos en enfermería de las Unidades de Cuidados Intensivos. Se recolectaron datos sociodemográficos, de salud y laborales y se aplicaron los instrumentos Maslach Burnout Inventory y Resilience at Work Scale 20. Los datos fueron sometidos a análisis descriptivo y a correlaciones bivariadas y parciales (análisis de redes). Resultados: la resiliencia en el trabajo tiene una correlación inversa con el agotamiento emocional (r= -0,545; p=0,01) y la despersonalización (r= -0,419; p=0,01) y directa con la realización profesional (r= 0,680; p=0,01). La variable con mayor influencia en la red de correlaciones fue la percepción del impacto de la pandemia en la salud mental. Conclusión: la resiliencia afecta los dominios agotamiento emocional y baja realización profesional del Burnout. El agotamiento emocional se manifiesta a través de trastornos psíquicos menores e impacta en las variables de salud física y mental de los trabajadores. Se debe fomentar el desarrollo de la resiliencia a nivel institucional para moderar la enfermedad.

High-Intense Interval Training Prevents Cognitive Impairment and Increases the Expression of Muscle Genes FNDC5 and PPARGC1A in a Rat Model of Alzheimer's Disease

BACKGROUND

Alzheimer's disease is the most common neurodegenerative disease in the world, characterized by the progressive loss of neuronal structure and function, whose main histopathological landmark is the accumulation of β-amyloid in the brain.

OBJECTIVE

It is well known that exercise is a neuroprotective factor and that muscles produce and release myokines that exert endocrine effects in inflammation and metabolic dysfunction. Thus, this work intends to establish the relationship between the benefits of exercise through the chronic training of HIIT on cognitive damage induced by the Alzheimer's model by the injection of β amyloid1-42.

METHODS

For this purpose, forty-eight male Wistar rats were divided into four groups: Sedentary Sham (SS), Trained Sham (ST), Sedentary Alzheimer's (AS), and Trained Alzheimer's (AT). Animals were submitted to stereotactic surgery and received a hippocampal injection of Aβ1-42 or a saline solution. Seven days after surgery, twelve days of treadmill adaptation followed by five maximal running tests (MRT) and fifty-five days of HIIT, rats underwent the Morris water maze test. The animals were then euthanized, and their gastrocnemius muscle tissue was extracted to analyze the Fibronectin type III domain containing 5 (FNDC5), PPARG Coactivator 1 Alpha (PPARGC1A), and Integrin subunit beta 5 (ITGB5-R) expression by qRT-PCR in addition to cross-sectional areas.

RESULTS

The HIIT prevents the cognitive deficit induced by the infusion of amyloid β1-42 (p < 0.0001), causes adaptation of muscle fibers (p < 0.0001), modulates the gene expression of FNDC5 (p < 0.01), ITGB5 (p < 0.01) and PPARGC1A (p < 0.01), and induces an increase in peripheral protein expression of FNDC5 (p < 0.005).

CONCLUSION

Thus, we conclude that HIIT can prevent cognitive damage induced by the infusion of Aβ1-42, constituting a non-pharmacological tool that modulates important genetic and protein pathways.

Morais L. OUP accepted manuscript

Recent research has been uncovering the role of the gut microbiota for brain health and disease. These studies highlight the role of gut microbiota on regulating brain function and behavior through immune, metabolic, and neuronal pathways. In this review we provide an overview of the gut microbiota axis pathways to lay the groundwork for upcoming sessions on the links between the gut microbiota and neurogenerative disorders. We also discuss how the gut microbiota may act as an intermediate factor between the host and the environment to mediate disease onset and neuropathology. Based on the current literature, we further examine the potential for different microbiota-based therapeutic strategies to prevent, to modify, or to halt the progress of neurodegeneration.

Burnout and resilience in intensive care Nursing professionals in the face of COVID-19: A multicenter study

Objective:

to analyze the relationship between the Burnout dimensions and the work resilience of intensive care Nursing professionals in the COVID-19 pandemic in four hospitals from southern Brazil.

Method:

this is a multicenter and cross-sectional study, composed of 153 nurses and nursing technicians of the Intensive Care Units. Sociodemographic, health and work-related questions were collected, and the Maslach Burnout Inventory and Resilience at Work Scale 20 instruments were applied. The data were submitted to descriptive analysis and to bivariate and partial correlations (network analysis).

Results:

work resilience presented an inverse correlation to emotional exhaustion (r=-0.545; p=0.01) and depersonalization (r=-0.419; p=0.01) and a direct one to professional achievement (r=0.680; p=0.01). The variable with the greatest influence on the correlation network was the perception of the impact of the pandemic on mental health.

Conclusion:

resilience interferes in the emotional exhaustion and low professional achievement domains of Burnout. Emotional exhaustion is conducted through minor psychological disorders, with an impact on the workers’ physical and mental health variables. The development of institutional resilience should be encouraged in order to moderate the illness.

Physical exercise shapes the mouse brain epigenome

OBJECTIVE

To analyze the genome-wide epigenomic and transcriptomic changes induced by long term resistance or endurance training in the hippocampus of wild-type mice.

METHODS

We performed whole-genome bisulfite sequencing (WGBS) and RNA sequencing (RNA-seq) of mice hippocampus after 4 weeks of specific training. In addition, we used a novel object recognition test before and after the intervention to determine whether the exercise led to an improvement in cognitive function.

RESULTS

Although the majority of DNA methylation changes identified in this study were training-model specific, most were associated with hypomethylation and were enriched in similar histone marks, chromatin states, and transcription factor biding sites. It is worth highlighting the significant association found between the loss of DNA methylation in Tet1 binding sites and gene expression changes, indicating the importance of these epigenomic changes in transcriptional regulation. However, endurance and resistance training activate different gene pathways, those being associated with neuroplasticity in the case of endurance exercise, and interferon response pathways in the case of resistance exercise, which also appears to be associated with improved learning and memory functions.

CONCLUSIONS

Our results help both understand the molecular mechanisms by which different exercise models exert beneficial effects for brain health and provide new potential therapeutic targets for future research.

Regular Physical Exercise Modulates Iron Homeostasis in the 5xFAD Mouse Model of Alzheimer's Disease

Dysregulation of brain iron metabolism is one of the pathological features of aging and Alzheimer's disease (AD), a neurodegenerative disease characterized by progressive memory loss and cognitive impairment. While physical inactivity is one of the risk factors for AD and regular exercise improves cognitive function and reduces pathology associated with AD, the underlying mechanisms remain unclear. The purpose of the study is to explore the effect of regular physical exercise on modulation of iron homeostasis in the brain and periphery of the 5xFAD mouse model of AD. By using inductively coupled plasma mass spectrometry and a variety of biochemical techniques, we measured total iron content and level of proteins essential in iron homeostasis in the brain and skeletal muscles of sedentary and exercised mice. Long-term voluntary running induced redistribution of iron resulted in altered iron metabolism and trafficking in the brain and increased iron content in skeletal muscle. Exercise reduced levels of cortical hepcidin, a key regulator of iron homeostasis, coupled with interleukin-6 (IL-6) decrease in cortex and plasma. We propose that regular exercise induces a reduction of hepcidin in the brain, possibly via the IL-6/STAT3/JAK1 pathway. These findings indicate that regular exercise modulates iron homeostasis in both wild-type and AD mice.