Roles of myokines in exercise-induced improvement of neuropsychiatric function

The effects of different types of exercises on cognition in older persons with mild cognitive impairment: A systematic review and meta-analysis

PURPOSE

This systematic review with meta-analysis aims to analyze the effects of different types of exercise on cognition, neuroprotective and neuroinflammatory blood markers in older adults with mild cognitive impairment (MCI).

METHODS

Relevant studies were identified using PubMED, SPORTDiscuss, Web of Science, Scopus, and PsycInfo databases. Methodological quality assessment of the studies was done with modified Downs and Black checklist. Data obtained from the included studies was analyzed using Comprehensive Meta-Analysis 4.0 software and results were reported using the random effects method.

RESULTS

A total of twenty-three studies were identified. The findings were summarized as change in cognitive function after the exercise interventions in general and after each type of exercise. On average, the exercise intervention revealed an effect size (ES): 1.165; 0.741 to 1.589 (95% Confidence Interval (CI); p < 0.001); aerobic exercise ES: 1.442; 0.624 to 2.260 (95 %CI); p = 0.001; Multimodal ES: 0,856; 0.366 to 1.346 (95 % CI); p = 0.001 and resistance exercise ES: 1.229; 0.339 to 2.120 (95 % CI); p = 0.007. In addition, we observed significant small ES: -0.475; -0.817 to -0.134 (95 %CI); p = 0.006, I2= 0 %; τ2 = 0 of exercise effects on Tumor Necrosis Factor-α (TNF-α) and non-significant large ES:0.952; -0.238 to 2.142 (95 %CI); p = 0.117 on Brain Derived Neurotrophic Factor (BDNF) in persons with MCI.

CONCLUSION

The present study revealed the existence of a large positive effect of overall exercise intervention on cognitive function and a small effect on TNF-α in old people with MCI. Additionally, this study demonstrates that aerobic and resistance exercises had similar larger positive effects and were better than multimodal exercise on increasing cognition in older persons with MCI.

How Can Promoting Skeletal Muscle Health and Exercise in Children and Adolescents Prevent Insulin Resistance and Type 2 Diabetes?

Skeletal muscle secretome, through its paracrine and endocrine functions, contributes to the maintenance and regulation of overall physiological health. We conducted a narrative review on the role of skeletal muscle and exercise in maintaining glucose homeostasis, driving insulin resistance (IR), and preventing type 2 diabetes in pediatric populations, especially in the context of overweight and obesity. Myokines such as interleukin (IL)-6, IL-8, and IL-15, as well as irisin, myonectin, and myostatin, appear to play a crucial role in IR. Skeletal muscle can also become a target of obesity-induced and IR-induced inflammation. In the correlation between muscle, IR, and inflammation, the role of infiltration of the immune cells and the microvasculature may also be considered. It remains unclear which exercise approach is the best; however, combining aerobic exercise with resistance training seems to be the most effective strategy for managing IR, with high-intensity activities offering superior metabolic benefits and long-term adherence. Encouraging daily participation in enjoyable and engaging exercise is key for long-term commitment and effective glucose metabolism management. Promoting physical activity in children and adolescents must be a top priority for public health, not only in terms of individual quality of life and well-being but also for community health.

Low hand grip strength as an indicator of depression in the Korean population: a large-scale cross-sectional study

Background

Depression is one of the leading global mental health problems, and hand grip strength (HGS) is associated with depression. However, there have been no studies assessing the association between depression and relative HGS indices combined with waist circumference (WC) and the waist-to-height ratio (WHtR). The objective of this study was to examine the association of depression with absolute and relative HGS indices.

Methods

This was a cross-sectional study based on the Korea National Health and Nutrition Examination Survey from 2014 to 2019. A total of 20,649 participants (8,959 men, 43.4% and 11,690 women, 56.6%) were included. The associations between depression and the HGS indices were analyzed through complex sample binary logistic regression models, which were adjusted for age in Model 1 and various covariates in Model 2.

Results

The prevalence of depression was 4.58%, with rates of 2.29% for men and 6.34% for women. The prevalence of depression in women was 2.76 times greater than that in men. In men, the mean HGS values in the dominant hand were 35.48 ± 0.75 kg in the depression group and 38.73 ± 0.11 kg in the non-depression group; in women, they were 21.37 ± 0.22 kg in the depression group and 22.77 ± 0.07 kg in the non-depression group. In men, relative HGS indices as HGS/WC, HGS/body mass index, and HGS/WHtR were more strongly associated with depression than were the absolute HGS indices; however, in women, the associations were similar for both absolute and relative HGS indices. The magnitude of the association was greater for men than for women. In both sexes, all the anthropometric indices had a lower association with depression than did the HGS indices.

Conclusion

Low absolute and relative HGS were negatively associated with depression in the Korean population. But, relative HGS indices were more strongly associated with depression than were absolute HGS and anthropometric indices in men but not in women.

Resistance exercise effects on hippocampus subfield volumes and biomarkers of neuroplasticity and neuroinflammation in older adults with low and high risk of mild cognitive impairment: a randomized controlled trial

Physical exercise is suggested to promote hippocampal neuroplasticity by increasing circulating neurotrophic and anti-inflammatory factors. Our aim was to explore the interplay between the effect of progressive resistance exercise on blood biomarker levels, hippocampal neurometabolite levels and hippocampal volume in older adults with a low compared to a high risk of mild cognitive impairment (MCI). Seventy apparently healthy male/female older adults (aged 60-85 years old) were randomly allocated to a 12 week lower limb progressive resistance or no intervention, stratified for low (< 26/30) or high (≥ 26/30) Montreal Cognitive Assessment (MoCA) score, indicating MCI risk. Outcome measures were blood levels of insulin-like growth factor-1 (IGF-1), interleukin-6 (IL-6) or kynurenine (KYN); hippocampal total and subfield volumes of the cornu ammonis 1 (CA1) and 4 (CA4), subiculum, presubiculum, and dentate gyrus measured with magnetic resonance imaging (MRI); and hippocampus neurometabolites including total N-acetylaspartate (NAA), myo-inositol (mIns), and total creatine (Cr) measured with proton magnetic resonance spectroscopy (1H-MRS). We evaluated the intervention effect, cognitive status effect, their interaction and the bivariate relationship between exercise-induced changes between the outcome measures. Higher kynurenine levels (p = 0.015) and lower subiculum volumes (p = 0.043) were found in older adults with high MCI risk compared to older adults with low MCI risk. Exercise-induced CA1 volume changes were negatively correlated with hippocampal tNAA/mIns level changes (r = -0.605, p = 0.006). This study provides valuable insight in the multifactorial processes related to resistance training in older adults with low or high MCI risk.

Development of a prediction model for cognitive impairment of sarcopenia using multimodal neuroimaging in non-demented older adults

INTRODUCTION

Despite prior research on the association between sarcopenia and cognitive impairment in the elderly, a comprehensive model that integrates various brain pathologies is still lacking.

METHODS

We used data from 528 non-demented older adults with or without sarcopenia in the Catholic Aging Brain Imaging (CABI) database, containing magnetic resonance imaging scans, positron emission tomography scans, and clinical data. We also measured three key components of sarcopenia: skeletal muscle index (SMI), hand grip strength (HGS), and the five times sit-to-stand test (5STS).

RESULTS

All components of sarcopenia were significantly correlated with global cognitive function, but cortical thickness and amyloid-beta (Aβ) retention had distinctive relationships with each measure. In the path model, brain atrophy resulting in cognitive impairment was mediated by Aβ retention for SMI and periventricular white matter hyperintensity for HGS, but directly affected by the 5STS.

DISCUSSION

Treatments targeting each sub-domain of sarcopenia should be considered to prevent cognitive decline.

HIGHLIGHTS

We identified distinct impacts of three sarcopenia measures on brain structure and Aβ. Muscle mass is mainly associated with Aβ and has an influence on the brain atrophy. Muscle strength linked with periventricular WMH and brain atrophy. Muscle function associated with cortical thinning in specific brain regions. Interventions on sarcopenia may be important to ease cognitive decline in the elderly.

Mild cognitive impairment predicts the onset of Sarcopenia: a longitudinal analysis from the English Longitudinal Study on Ageing

BACKGROUND

Mild cognitive impairment (MCI) and sarcopenia are two common conditions in older people. It is not widely known if MCI could predict the onset of sarcopenia. Therefore, we aimed to investigate whether MCI could predict the occurrence of sarcopenia in a population of older adults.

METHODS

In the ELSA (English Longitudinal Study on Ageing), MCI was defined as the absence of dementia, preserved functional capacity and low performance in three objective cognitive tests. Sarcopenia was diagnosed as having low handgrip strength and low skeletal muscle mass index during follow-up. The longitudinal association between MCI at the baseline and incident sarcopenia was assessed using a multivariable logistic regression model, reporting the data as adjusted odds ratios (OR) and 95% confidence intervals (95%CI).

RESULTS

3,106 participants (mean age of 63.1 years; 55.3% males) were included. People with MCI reported significantly lower mean handgrip strength values and Skeletal Mass Index (SMI), as well as a higher prevalence of obesity at baseline. At baseline, 729 people had MCI and during the ten years follow-up period, 12.1% of the initial population included had sarcopenia. On multivariate analysis, adjusted for 18 potential confounders, the presence of MCI (OR = 1.236; 95%CI: 1.090-1.596, p = 0.01) significantly predicted the onset of sarcopenia during follow-up.

CONCLUSION

The presence of MCI at baseline was associated with a higher incidence of sarcopenia at ten-years follow-up, demonstrating a likely role of MCI as a predictor of the onset of sarcopenia in older people.

Neuronal innervation regulates the secretion of neurotrophic myokines and exosomes from skeletal muscle

Myokines and exosomes, originating from skeletal muscle, are shown to play a significant role in maintaining brain homeostasis. While exercise has been reported to promote muscle secretion, little is known about the effects of neuronal innervation and activity on the yield and molecular composition of biologically active molecules from muscle. As neuromuscular diseases and disabilities associated with denervation impact muscle metabolism, we hypothesize that neuronal innervation and firing may play a pivotal role in regulating secretion activities of skeletal muscles. We examined this hypothesis using an engineered neuromuscular tissue model consisting of skeletal muscles innervated by motor neurons. The innervated muscles displayed elevated expression of mRNAs encoding neurotrophic myokines, such as interleukin-6, brain-derived neurotrophic factor, and FDNC5, as well as the mRNA of peroxisome-proliferator-activated receptor γ coactivator 1α, a key regulator of muscle metabolism. Upon glutamate stimulation, the innervated muscles secreted higher levels of irisin and exosomes containing more diverse neurotrophic microRNAs than neuron-free muscles. Consequently, biological factors secreted by innervated muscles enhanced branching, axonal transport, and, ultimately, spontaneous network activities of primary hippocampal neurons in vitro. Overall, these results reveal the importance of neuronal innervation in modulating muscle-derived factors that promote neuronal function and suggest that the engineered neuromuscular tissue model holds significant promise as a platform for producing neurotrophic molecules.

Association between handgrip strength and depressive symptoms in patients undergoing hemodialysis: a cross-sectional study from a single Chinese center

BACKGROUND

The relationship between handgrip strength (HGS) and depression in patients undergoing hemodialysis (HD) was unknown. Therefore, we aimed to clarify this association in a cohort of patients.

METHODS

HGS was used as a representative indicator of muscle strength and was measured with a handheld dynamometer. Depressive symptoms were assessed with the self-reported Patient Health Questionnaire-9. A multivariable logistic regression model and restricted cubic spline analysis were used to assess the relationship between HGS and depression.

RESULTS

The prevalence of depression in our study was 34% in 568 Chinese patients undergoing HD. Compared with patients in the lowest tertiles of absolute and weighted HGS, patients in the highest tertiles of HGS had an approximately 59% lower [odds ratio (OR) = 0.41, 95% confidence interval (CI) = 0.24-0.68; OR = 0.41, 95%CI = (0.24-0.69)] prevalence of depressive symptoms after multivariate adjustments. Besides, the risk of depression in hemodialysis patients decreased by 33% (OR = 0.67, 95%CI = 0.53-0.85) and 32% (OR = 0.68, 95%CI = 0.54-0.85) for each standard deviation increase in absolute HGS and weighted HGS, respectively. The prevalence of depressive symptoms decreased with both increasing absolute HGS and weighted HGS after multivariate adjustments (p for trend < 0.05). Furthermore, a linear dose-response relationship was observed between absolute HGS and weighted HGS and the prevalence of depressive symptoms (pnonlinearity>0.05).

CONCLUSIONS

This study suggests that lower handgrip strength, a simple and modifiable parameter, is associated with a higher prevalence of depression in Chinese patients undergoing HD. Considering that depression is often unrecognized or underdiagnosed in HD patients, lowered muscle strength should be an important indicator and incentive for medical staff to screen for depression.

Effects of an acute bout of cycling on different domains of cognitive function

The literature suggesting acute exercise benefits cognitive function has been largely confined to single cognitive domains and measures of reliant on measures of central tendencies. Furthermore, studies suggest cognitive intra-individual variability (IIV) to reflect cognitive efficiency and provide unique insights into cognitive function, but there is limited knowledge on the effects of acute exercise on IIV. To this end, this study examined the effects of acute exercise on three different cognitive domains, executive function, implicit learning, and hippocampal-dependent memory function using behavioral performance and event-related potentials (ERPs). Furthermore, this study also sought to explore the effects of an acute bout of exercise on IIV using the RIDE algorithm to separate signals into individuals components based on latency variability. Healthy adult participants (N=20; 26.3±4.8years) completed a randomized cross-over trial with seated rest or 30min of high intensity cycling. Before and after each condition, participants completed a cognitive battery consisting of the Eriksen Flanker task, implicit statistical learning task, and a spatial reconstruction task. While exercise did not affect Flanker or spatial reconstruction performance, there were exercise related decreases in accuracy (F=5.47; P=0.040), slowed reaction time (F=5.18; P=0.036), and decreased late parietal positivity (F=4.26; P=0.046). However, upon adjusting for performance and ERP variability, there were exercise related decreases in Flanker reaction time (F=24.00; P<0.001), and reduced N2 amplitudes (F=13.03; P=0.002), and slower P3 latencies (F=3.57; P=0.065) for incongruent trials. These findings suggest that acute exercise may impact cognitive IIV as an adaptation to maintain function following exercise.

Time-resolved map of serum metabolome profiling in D-galactose-induced aging rats with exercise intervention

Exercise, an intervention with wide-ranging effects on the whole body, has been shown to delay aging. Due to aging and exercise as modulator of metabolism, a picture of how exercise delayed D-galactose (D-gal)-induced aging in a time-resolved manner was presented in this paper. The mapping of molecular changes in response to exercise has become increasingly accessible with the development of omics techniques. To explore the dynamic changes during exercise, the serum of rats and D-gal-induced aging rats before, during, and after exercise was analyzed by untargeted metabolomics. The variation of metabolites was monitored to reveal the specific response to D-gal-induced senescence and exercise in multiple pathways, especially the basal amino acid metabolism, including glycine serine and threonine metabolism, cysteine and methionine metabolism, and tryptophan metabolism. The homeostasis was disturbed by D-gal and maintained by exercise. The paper was expected to provide a theoretical basis for the study of anti-aging exercise.

Physical performance and negative events in very old adults: a longitudinal study examining the ilSIRENTE cohort

BACKGROUND

Declining physical performance in old age is associated with a wide range of negative health-related outcomes. However, it is unclear which physical capabilities should be prioritized to obtain prognostic information in older adults.

AIMS

To examine the associations between the performance on several physical function tests and falls, disability, and death in a well-characterized sample of very old Italian adults.

METHODS

This was a prospective cohort study of older adults who lived in the mountain community of the Sirente geographic area in Central Italy. Physical performance was assessed using isometric handgrip strength (IHG), walking speed (WS) at a usual and fast pace, 5-time sit-to-stand test (5STS), and sit-to-stand power measures. Appendicular skeletal muscle mass was estimated from calf circumference using a validated equation. History of falls, incident falls, and disability status according to basic Activities of Daily Living (ADLs) were recorded over two years. Survival status was obtained from the participants' general practitioners and was confirmed by the National Death Registry over 10 years from enrolment. Linear, binary, and Cox regressions were performed to evaluate the association between physical performance measures and health outcomes.

RESULTS

The mean age of the 255 participants was 84.2 ± 5.1 years, and 161 (63.1%) were women. Logistic regression indicated that IHG was significantly associated with incident ADL disability, whereas specific sit-to-stand muscle power was an independent predictor of death. No significant associations were observed between physical function and falls.

CONCLUSIONS

Our findings indicate selective associations between physical function tests and the occurrence of negative events in very old adults, with poor IHG predicting disability and specific sit-to-stand muscle power being longitudinally associated with death.

Solanum melongena extract supplementation protected skeletal muscle and brain damage by regulation of BDNF/PGC1α/irisin pathway via brain function-related myokines in high-fat diet induced obese mice

In this study, we investigated the protective effects of SM on skeletal muscle and brain damage by regulation of BDNF/PGC1α/irisin pathway via brain function related myokines in high-fat diet-induced OB mice. OB was induced by high-fat diet for 6 weeks. SM extract (SME) was administered with 200 mg/kg BW (LSM) and 500 mg/kg BW (HSM) by oral gavage every day for 12 weeks. Behavior tests such as grip strength, Y-maze, and passive avoidance test were conducted to analyze muscle and cognitive function. Histopathological changes in skeletal muscle and brain were examined by hematoxylin and eosin staining and the protein levels of biomarkers related to oxidative stress, inflammation, protein degradation, neuro-plasticity, and cell cycling were measured by western blot. SME regulated morphological changes (muscle cross-sectional area: 1.23%, 1.40%; density of neurons in hippocampus:1.74%, 1.73%) in T2DM mice. Importantly, SME supplementation significantly increased several muscle-derived myokines which might influence the expression of neuronal markers in OB mice (FGF21: 1.27%, 1.34%; PGC1α: 1.0%, 1.32%; IRISIN: 1.9%, 1.08%; BDNF: 1.35%, 1.23%). Accordingly, SME activated hippocampal neurotrophic factors including BDNF (1.0%, 1.2%) and its associated PGC1α/irisin pathway (PGC1α :1.1%, 1.1%; IRISIN:1.1%, 0.9%) significantly. This study demonstrated the possibliy that protective myokines increased by SME supplementation may contribute to neuro-protection in OB mice. Taken together, the current study suggests that SME can be used to prevent skeletal muscle and brain damage in OB by protecting against oxidative stress and inflammatin via modulation of the BDNF/PGC1α/irisin pathway in the therapeutic approach of obese patients.

Clinical effects and biological mechanisms of exercise on lumbar disc herniation

Lumbar Disc Herniation (LDH) is a syndrome in which lumbar disc degeneration, rupture of the annulus fibrosus, and herniation of the nucleus pulposus irritate and compress the nerve roots and cauda equina, resulting in the main manifestations of lumbar pain and/or lower extremity pain. There is evidence in various clinical areas that exercise is effective in treating LDH, and exercise intervention for more than 2 weeks reduces disease activity in LDH. However, the mechanism of exercise's action in reducing disease activity in LDH is unclear. In this article, we first summarize and highlight the effectiveness of exercise in treating LDH and provide guideline recommendations regarding exercise type, intensity, frequency, and duration. Then, we integrate the existing evidence and propose biological mechanisms for the potential effects of exercise on neuromechanical compression, inflammatory chemical stimuli, and autoimmune responses from the perspective of LDH pathogenesis as an entry point. However, a large body of evidence was obtained from non-LDH populations. Future research needs to investigate further the proposed biological mechanisms of exercise in reducing disease activity in LDH populations. This knowledge will contribute to the basic science and strengthen the scientific basis for prescribing exercise therapy for the routine clinical treatment of LDH.

High-intensity combination exercise has the highest effect on increasing serum irisin and interleukin 6 levels in women with obesity

OBJECTIVES

Lifestyle, overnutrition, socioeconomic status, environmental conditions, and genetics are factors that cause obesity. Lifestyle modification with a nonpharmacological approach based on physical exercise is the starting point in overcoming obesity. However, physical exercise with the appropriate and effective intensity for obese subjects is still debated. Therefore, this study aims to prove the effect of intensity differences with aerobic-resistance combination exercise on increasing irisin and IL-6 levels in obese women.

METHODS

A total of 32 obese women were selected as subjects and administered the interventions of low-intensity combination exercise (Q2), moderate-intensity combination exercise (Q3), and high-intensity combination exercise (Q4). ELISA was used to measure irisin and IL-6 levels in all samples. Statistical analysis used one-way ANOVA and Turkey's-Honest Significant Difference (HSD) post hoc test.

RESULTS

The mean Δ IL-6 levels in the control groups (Q1), Q2, Q3, and Q4 were 0.27 ± 2.54, 2.07 ± 2.55, 5.99 ± 6.25, and 7.98 ± 2.82 pg/mL with (p=0.015). The mean Δ irisin levels were 0.06 ± 0.81 ng/mL in Q1, 0.59 ± 0.67 ng/mL in Q2, 1.99 ± 1.65 ng/mL in Q3, 4.63 ± 3.57 ng/mL in Q4 with (p=0.001).

CONCLUSIONS

This study proved that all three types of combined exercise intensity increased myokine levels, such as irisin and IL-6. However, high-intensity combination exercise provided the most optimal improvement in myokine levels in obese women. Future studies are needed to design long-term exercise programs specifically for obese adolescent women using the findings from this study.

Exercise Intervention for Alzheimer's Disease: Unraveling Neurobiological Mechanisms and Assessing Effects

Alzheimer's disease (AD) is a progressive neurodegenerative disease and a major cause of age-related dementia, characterized by cognitive dysfunction and memory impairment. The underlying causes include the accumulation of beta-amyloid protein (Aβ) in the brain, abnormal phosphorylation, and aggregation of tau protein within nerve cells, as well as neuronal damage and death. Currently, there is no cure for AD with drug therapy. Non-pharmacological interventions such as exercise have been widely used to treat AD, but the specific molecular and biological mechanisms are not well understood. In this narrative review, we integrate the biology of AD and summarize the knowledge of the molecular, neural, and physiological mechanisms underlying exercise-induced improvements in AD progression. We discuss various exercise interventions used in AD and show that exercise directly or indirectly affects the brain by regulating crosstalk mechanisms between peripheral organs and the brain, including "bone-brain crosstalk", "muscle-brain crosstalk", and "gut-brain crosstalk". We also summarize the potential role of artificial intelligence and neuroimaging technologies in exercise interventions for AD. We emphasize that moderate-intensity, regular, long-term exercise may improve the progression of Alzheimer's disease through various molecular and biological pathways, with multimodal exercise providing greater benefits. Through in-depth exploration of the molecular and biological mechanisms and effects of exercise interventions in improving AD progression, this review aims to contribute to the existing knowledge base and provide insights into new therapeutic strategies for managing AD.

The impact of resistance training on brain-derived neurotrophic factor and depression among older adults aged 60 years or older: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

This systematic review and meta-analysis aimed to investigate the impact of resistance training on brain-derived neurotrophic factor (BDNF) and depression among older adults aged 60 years or older.

METHOD

Four electronic databases were systematically searched.

RESULTS

A total of 11 randomized controlled trials, with a pooled sample of 868 participants, met our inclusion criteria. Meta-analysis demonstrated that resistance training significantly improved circulating BDNF levels (mean difference; MD: 0.73 ng/ml; 95% CI [0.04, 1.42]; p = 0.04). Additionally, resistance training was associated with significant improvements in depression (standardized mean difference; SMD: -0.38; 95% CI [- 0.62, -0.14]; p = 0.002).

DISCUSSION

These findings suggest that resistance training may be an effective intervention for improving BDNF levels and reducing depression symptoms in older adults. Further research is needed to confirm these findings and to investigate the underlying mechanisms.

One-year change in sarcopenia was associated with cognitive impairment among haemodialysis patients

BACKGROUND

Our study aimed to evaluate change in sarcopenia, its defining components over 1 year follow-up and investigate associations with subsequent cognitive decline, incident mild cognitive impairment (MCI) and dementia among patients undergoing haemodialysis (HD).

METHODS

In the multicentre, longitudinal study, 1117 HD patients aged 56.8 ± 14.3 years (654 men; and 463 women) from 17 dialysis centres in Guizhou Province, China, were recruited in 2019 and followed up for 1 year in 2020. Sarcopenia was diagnosed with Asian Working Group for Sarcopenia criteria using appendicular skeletal muscle mass index (ASMI) and handgrip strength (HGS). Body composition was measured using body composition monitor; body water, weight, and height were corrected to calculate ASMI. HGS was measured by mechanical handgrip dynamometer. Cognitive function was measured with Mini Mental State Examination. Multivariate linear, logistic regression models and subgroup analyses were employed to examine the associations of changes in sarcopenia, ASMI, and HGS with Mini Mental State Examination score change, and incident MCI, dementia.

RESULTS

Four hundred fourteen (37.1%) patients had sarcopenia at baseline; during 1 year follow-up, 257 (23.0%) developed MCI and 143 (12.8%) developed dementia. According to changes in sarcopenia, patients were stratified into four groups: non-sarcopenia; non-sarcopenia to sarcopenia; sarcopenia; and sarcopenia to non-sarcopenia. HD patients in sarcopenia and non-sarcopenia to sarcopenia groups had higher risk of MCI (34.8%, 32.0%, vs. 17.4%) and dementia (20.6%, 19.8%, vs. 8.7%), compared non-sarcopenia group (P < 0.001). Multivariate linear regression analyses showed that sarcopenia [regression coefficients (β) -1.098, 95% confidence interval (CI) -1.872, -0.324, P = 0.005] and non-sarcopenia to sarcopenia (β -1.826, -2.441, -1.212, P < 0.001) were associated with faster cognitive decline compared to non-sarcopenia. HGS decline (β 0.046, 0.027-0.064, P < 0.001) and ASMI decline (β 0.236, 0.109-0.362, P < 0.001) were both positively associated with cognitive decline. Multivariate logistic regression analyses demonstrated that patients with sarcopenia and non-sarcopenia to sarcopenia were both at increased risk of developing MCI [odds ratio (OR) 1.788, 95% CI 1.115-2.870, P = 0.016 and OR 1.589, 95% CI 1.087-2.324, P = 0.017, respectively], but only non-sarcopenia to sarcopenia was at increased risk of dementia (OR 1.792, 95% CI 1.108-2.879, P = 0.017). Both greater change of ASMI and HGS had lower risk of MCI with adjusted ORs of 0.857 (0.778-0.945, P = 0.002) and 0.976 (0.963-0.989, P < 0.001). Robust associations were found among female individuals, aged >60 years, and with low educational level.

CONCLUSIONS

Longitudinal associations were observed between new-onset, persistent sarcopenia, and cognitive impairment. Early detection and intervention should be implemented to delay the onset of sarcopenia and improve cognitive health among HD patients.

Adult hippocampal neurogenesis (AHN) controls central nervous system and promotes peripheral nervous system regeneration via physical exercise

Physical exercise has beneficial effects on adult hippocampal neurogenesis (AHN) and cognitive processes, including learning. Although it is not known if anaerobic resistance training and high-intensity interval training, which involve alternating brief bouts of highly intense anaerobic activity with rest periods, have comparable effects on AHN. Also, while less thoroughly investigated, individual genetic diversity in the overall response to physical activity is likely to play a key role in the effects of exercise on AHN. Physical exercise has been shown to improve health on average, although the benefits may vary from person to person, perhaps due to genetic differences. Maximal aerobic capacity and metabolic health may improve significantly with aerobic exercise for some people, while the same amount of training may have little effect on others. This review discusses the AHN's capability for peripheral nervous system (PNS) regeneration and central nervous system (CNS) control via physical exercise. Exercise neurogenicity, effective genes, growth factors, and the neurotrophic factors involved in PNS regeneration and CNS control were discussed. Also, some disorders that could be affected by AHN and physical exercise are summarized.

The Relationship Between Exercise, Cathepsin B, and Cognitive Functions: Systematic Review

Exercise has been shown repeatedly to improve cognitive functions. Many investigators have reported that peripheral signal molecules play an important role in regulating exercise-induced cognitive improvement. In this review we aimed to evaluate and clarify the literature to date that has focused on the relationship between Cathepsin B, cognitive functions, and exercise. We conducted a systematic review of the following databases from their inception until 10 April 2022: Pubmed, Web of Science, Scopus, Cochrane Library, Physiotherapy Evidence Database. The search strategy was comprised of ("cathepsin b") AND (exercise OR "physical activity") AND (cognit*). We followed three different quality appraisal tools to ensure the quality of the included studies. Eight studies assessing the effects of exercise on peripheral Cathepsin B levels and cognitive outcomes were included. Half of these studies indicated that exercise increased peripheral Cathepsin B levels and improved cognitive function. Further carefully designed studies focusing on the effects of exercise on peripheral Cathepsin B levels and cognitive performance are needed to better comprehend the underlying mechanisms of these relationships.

Muscle-Brain crosstalk in cognitive impairment

Sarcopenia is an age-related, involuntary loss of skeletal muscle mass and strength. Alzheimer's disease (AD) is the most common cause of dementia in elderly adults. To date, no effective cures for sarcopenia and AD are available. Physical and cognitive impairments are two major causes of disability in the elderly population, which severely decrease their quality of life and increase their economic burden. Clinically, sarcopenia is strongly associated with AD. However, the underlying factors for this association remain unknown. Mechanistic studies on muscle-brain crosstalk during cognitive impairment might shed light on new insights and novel therapeutic approaches for combating cognitive decline and AD. In this review, we summarize the latest studies emphasizing the association between sarcopenia and cognitive impairment. The underlying mechanisms involved in muscle-brain crosstalk and the potential implications of such crosstalk are discussed. Finally, future directions for drug development to improve age-related cognitive impairment and AD-related cognitive dysfunction are also explored.

[Paracrine and endocrine functions of muscles]

BACKGROUND

Myokines discharged from working muscles are intensively researched in view of rising importance of preventive and secondary preventive effects of the autocrine, paracrine and endocrine functions.

OBJECTIVES

Recording of the current state of knowledge on the paracrine and endocrine effects of myokines and evaluation of training measures to optimize myokine concentration.

METHOD

A selective database-driven literature search was carried out on myostatin, interleukin-6 (IL-6), interleukin-15 (IL-15), irisin, cathepsin B, brain-derived neurotrophic factor (BDNF), meteorin-like and kynurenine for the period 2011 until June 2021. The paracrine and endocrine effects of the myokines are analyzed. Their release after acute physical stress and training is described.

RESULTS

IL-6 and IL-15 act in lipid metabolism and carbohydrate metabolism, IL-6 also in the brain and immune system. Irisin produces a conversion of white to brown adipose tissue ("browning"), so does meteorin-like. Cathepsin B has a central effect. Kynurenine acts indirectly via kynurenic acid in the brain. The secretion of myokines depends on the intensity of physical stress and is modified by training. Prevention of vascular and neurologic diseases, cognitive enhancement and increased immunological function can be reached by setting free myokines during physical activity. Therapeutical use by technologically modified myokines is proposed in metabolic and neurological diseases, immobilization and sarcopenia.

CONCLUSIONS

The current research situation on myokines gives reason to recommend regular muscular activity in addition to the previously evidence-based benefits of sport in order to achieve preventive and therapeutic effects.

Sport and physical exercise in sustainable mental health care of common mental disorders: Lessons from the COVID-19 pandemic

The large-scale disruptions to physical activity during the coronavirus pandemic have been found to be a leading predictor of common mental disorders. In addition, regular physical exercise has been found to alleviate anxiety, sadness and depression during the pandemic. These findings, together with numerous studies published before the pandemic on the effects of physical activity on mental health, should be considered in the provision of mental health care following the pandemic. Cross-sectional research has revealed that all types of exercise and sport are associated with a reduced mental health burden. Therefore, the effectiveness of exercise and sport participation in sustainable mental health care as well as the causal relationship between exercise, psychosocial health and common mental disorders merit further investigation. Physical activity and sport, with their global accessibility, significant and clinically meaningful efficacy as well as virtual absence of adverse effects, offer a promising option for the promotion of mental health, including the prevention and treatment of common mental disorders. Physical exercise and sport are likely to become valuable public mental health resources in the future.

Effect of early mobilisation on long-term cognitive impairment in critical illness in the USA: a randomised controlled trial

BACKGROUND

Patients who have received mechanical ventilation can have prolonged cognitive impairment for which there is no known treatment. We aimed to establish whether early mobilisation could reduce the rates of cognitive impairment and other aspects of disability 1 year after critical illness.

METHODS

In this single-centre, parallel, randomised controlled trial, patients admitted to the adult medical-surgical intensive-care unit (ICU), at the University of Chicago (IL, USA), were recruited. Inclusion criteria were adult patients (aged ≥18 years) who were functionally independent and mechanically ventilated at baseline and within the first 96 h of mechanical ventilation, and expected to continue for at least 24 h. Patients were randomly assigned (1:1) via computer-generated permuted balanced block randomisation to early physical and occupational therapy (early mobilisation) or usual care. An investigator designated each assignment in consecutively numbered, sealed, opaque envelopes; they had no further involvement in the trial. Only the assessors were masked to group assignment. The primary outcome was cognitive impairment 1 year after hospital discharge, measured with a Montreal Cognitive Assessment. Patients were assessed for cognitive impairment, neuromuscular weakness, institution-free days, functional independence, and quality of life at hospital discharge and 1 year. Analysis was by intention to treat. This trial was registered with ClinicalTrials.gov, number NCT01777035, and is now completed.

FINDINGS

Between Aug 11, 2011, and Oct 24, 2019, 1222 patients were screened, 200 were enrolled (usual care n=100, intervention n=100), and one patient withdrew from the study in each group; thus 99 patients in each group were included in the intention-to-treat analysis (113 [57%] men and 85 [43%] women). 65 (88%) of 74 in the usual care group and 62 (89%) of 70 in the intervention group underwent testing for cognitive impairment at 1 year. The rate of cognitive impairment at 1 year with early mobilisation was 24% (24 of 99 patients) compared with 43% (43 of 99) with usual care (absolute difference -19·2%, 95% CI -32·1 to -6·3%; p=0·0043). Cognitive impairment was lower at hospital discharge in the intervention group (53 [54%] 99 patients vs 68 [69%] 99 patients; -15·2%, -28·6 to -1·7; p=0·029). At 1 year, the intervention group had fewer ICU-acquired weaknesses (none [0%] of 99 patients vs 14 [14%] of 99 patients; -14·1%; -21·0 to -7·3; p=0·0001) and higher physical component scores on quality-of-life testing than did the usual care group (median 52·4 [IQR 45·3-56·8] vs median 41·1 [31·8-49·4]; p<0·0001). There was no difference in the rates of functional independence (64 [65%] of 99 patients vs 61 [62%] of 99 patients; 3%, -10·4 to 16·5%; p=0·66) or mental component scores (median 55·9 [50·2-58·9] vs median 55·2 [49·5-59·7]; p=0·98) between the intervention and usual care groups at 1 year. Seven adverse events (haemodynamic changes [n=3], arterial catheter removal [n=1], rectal tube dislodgement [n=1], and respiratory distress [n=2]) were reported in six (6%) of 99 patients in the intervention group and in none of the patients in the usual care group (p=0·029).

INTERPRETATION

Early mobilisation might be the first known intervention to improve long-term cognitive impairment in ICU survivors after mechanical ventilation. These findings clearly emphasise the importance of avoiding delays in initiating mobilisation. However, the increased adverse events in the intervention group warrants further investigation to replicate these findings.

FUNDING

None.

Sarcopenia and Cognitive Decline in Older Adults: Targeting the Muscle-Brain Axis

Declines in physical performance and cognition are commonly observed in older adults. The geroscience paradigm posits that a set of processes and pathways shared among age-associated conditions may also serve as a molecular explanation for the complex pathophysiology of physical frailty, sarcopenia, and cognitive decline. Mitochondrial dysfunction, inflammation, metabolic alterations, declines in cellular stemness, and altered intracellular signaling have been observed in muscle aging. Neurological factors have also been included among the determinants of sarcopenia. Neuromuscular junctions (NMJs) are synapses bridging nervous and skeletal muscle systems with a relevant role in age-related musculoskeletal derangement. Patterns of circulating metabolic and neurotrophic factors have been associated with physical frailty and sarcopenia. These factors are mostly related to disarrangements in protein-to-energy conversion as well as reduced calorie and protein intake to sustain muscle mass. A link between sarcopenia and cognitive decline in older adults has also been described with a possible role for muscle-derived mediators (i.e., myokines) in mediating muscle-brain crosstalk. Herein, we discuss the main molecular mechanisms and factors involved in the muscle-brain axis and their possible implication in cognitive decline in older adults. An overview of current behavioral strategies that allegedly act on the muscle-brain axis is also provided.

Association between Reduction of Muscle Mass and Faster Declines in Global Cognition among Older People: A 4-Year Prospective Cohort Study

OBJECTIVES

A few studies reported that both decrease and increase in body mass index (BMI) were associated with the development of dementia in later life. However, it is unclear what changes in body composition are associated with cognitive decline. This study investigated the longitudinal influences of changes in body composition on cognitive function among community-dwelling adults.

DESIGN, SETTING AND PARTICIPANTS

This longitudinal study included older adults aged ≥60 years without cognitive impairment who participated in National Institute for Longevity Sciences - Longitudinal Study of Aging.

MEASUREMENTS

Cognitive function was assessed using the MMSE. Body composition was measured by a dual-energy X-ray absorptiometry system. Then, BMI, fat mass index (FMI), fat-free mass index (FFMI), and muscle mass index (MMI) were calculated. The changes in body composition over 6 years (second wave to fifth wave) were calculated, and three groups were created: decreased group, decrease of >5%; stable group, change within 5%, and increased group, increase of >5%. In statistical analysis, a linear mixed model was applied by sex to investigate the influences of body composition changes on cognitive function over 4 years (fifth wave to seventh wave).

RESULTS

This study analyzed 515 participants (mean age, 67.05 years; 53.4% men). Men with decreased group in FFMI and MMI exhibited faster declines in MMSE scores than those with stable group (β [95% CI]: FFMI, -0.293 [-0.719 to -0.020]; MMI, -0.472 [-0.884 to -0.059]). In women, there was no significant association between body composition changes and cognitive functions.

CONCLUSIONS

Decrease in fat-free mass and muscle mass is associated with faster cognitive declines in men. These results suggest the importance of continuous monitoring of muscle mass to prevent cognitive decline in later life.

Association between Sarcopenia and Cognitive Trajectories among Middle-Aged and Older Adults in China: A Nationally Representative Cohort Study

OBJECTIVES

The relationship between sarcopenia and cognitive function has been extensively studied, but is usually explored at a single time point. We used repeatedly measured cognitive data to examine the relationship between sarcopenia and cognitive trajectories over time among middle-aged and older Chinese adults.

DESIGN

A nationally representative cohort study.

SETTING AND PARTICIPANTS

Data were from three waves (2011, 2013 and 2015) of the China Health and Retirement Longitudinal Study (CHARLS). A total of 8963 participants with complete baseline data (wave 1) and at least two cognitive function tests (waves 1-3) were enrolled in this study.

MEASUREMENTS

Sarcopenia was diagnosed at baseline (wave 1). The wave 1-3 data were used to analyze cognitive trajectories over time by constructing a latent class trajectory model (LCTM). Logistic regression model was used to analyze the association between sarcopenia and cognitive trajectories.

RESULTS

Among 8693 participants, we identified two trajectories of cognitive function development, including a persistent low trajectory (n= 4856, 55.86%) and a persistent high trajectory (n= 3837, 44.14%). Sarcopenia was associated with persistently low cognitive trajectory of global cognitive (OR: 1.248, 95%CI: 1.046-1.490) after adjustment for other covariates. This association was still observed when stratified by age, gender, educational level, marital status, social activity, smoking status and drinking status. Mediation analysis showed that body mass index (BMI) mediated efficacy accounting for 42.32% of the relationship.

CONCLUSIONS

Our study showed two trajectory groups of global cognitive function. Sarcopenia was associated with a persistent low trajectory over time and BMI mediated the relationship between sarcopenia and cognitive trajectories among middle-aged and older Chinese adults.

Resistance Training Combined With Cognitive Training Increases Brain Derived Neurotrophic Factor and Improves Cognitive Function in Healthy Older Adults

Background

The present study compared the effects of a traditional resistance training (TRT) and resistance training combined with cognitive task (RT + CT) on body composition, physical performance, cognitive function, and plasma brain-derived neurotrophic factor (BNDF) levels in older adults.

Methods

Thirty community-dwelling older adults were randomized into TRT (70.0 ± 8.1; 25% men) and RT + CT (66.3 ± 4.6; 31% men). Exercise groups performed a similar resistance training (RT) program, twice a week over 16 weeks. Cognitive Training involved performing verbal fluency simultaneously with RT. Exercise sessions (eight resistance exercises) were performed 2–3 sets, 8–15 repetitions at 60%–70% of 1-repetition maximum (1RM). Body composition, physical function, cognitive performance, and BDNF levels were assessed before and after intervention period.

Results

The physical performance was similarly improved in response to both TRT and RT + CT (p = 0.001). However, exclusive improvements on cognitive function (p < 0.001) and BDNF levels (p = 0.001) were observed only after RT + CT.

Conclusion

The RT program associated with a cognitive task, improved physical and cognitive performance in healthy older adults.

Post-stroke low-frequency whole-body vibration improves cognition in middle-aged rats of both sexes

Low-frequency whole-body vibration (WBV; 40 Hz), a low impact form of exercise, intervention for a month following moderate transient middle-cerebral artery occlusion (tMCAO) reduces infarct volume and improves motor function in reproductively senescent, middle-aged female rats. Since post-stroke cognitive decline remains a significant problem, the current study aims to investigate the efficacy of WBV in ameliorating post-tMCAO cognitive deficits and to determine the underlying putative mechanism(s) conferring benefits of WBV in middle-aged rats. Middle-aged rats of both sexes were randomly assigned to tMCAO (90 min) or sham surgery followed by exposure to either WBV (twice a day for 15 min each for 5 days a week over a month) or no WBV treatment groups. Following the last WBV treatment, rats were tested for hippocampus-dependent learning and memory using a water maze followed by harvesting brain and blood samples for histopathological and inflammatory marker analyses, respectively. Results show that post-tMCAO WBV significantly lessens cognitive deficits in rats of both sexes. Post-tMCAO WBV significantly decreased circulating pro-inflammatory cytokines and increased serum levels of irisin, a muscle-derived hormone that may play a role in brain metabolism and inflammation regulation, which suggests putative beneficial mechanisms of WBV.

Comparison of Rapid Cognitive Screen against Montreal Cognitive Assessment in screening for cognitive impairment in the old and old-old

BACKGROUND

The Montreal Cognitive Assessment (MoCA) was developed as a screening tool for mild cognitive impairment (MCI). Given the need for a rapid screening test in settings such as primary care, we compare the validity of the Rapid Cognitive Screen (RCS) against the MoCA, and determine cut-off scores in the old and old-old.

METHODS

Cross-sectional study involving community-dwelling 'old' (65 to 79 years old) and 'old-old' (≥ 80 years old) without dementia. Cognitive impairment was defined by MoCA score 17 to 22. Validation was done using the receiver operating characteristic (ROC) curve analysis: area under the curve (AUC), sensitivity (Sn), and specificity (Sp).

RESULTS

Of the 183 participants (mean age 72.1 ± 5.2 years),15.8% (n = 29) were classified as cognitively impaired. The overall ROC curve had an AUC of 0.82 (95% CI 0.75-0.90, P < 0.01) with an optimal cut-off of 7/8 on RCS (Sn 0.77, Sp 0.72). The 'old' and 'old-old' group had AUC of 0.82 (95% CI 0.74-0.91, P < 0.01) with 8/9 as optimal cut-off (Sn 0.51, Sp 0.96) and AUC of 0.85 (95% CI 0.66-1.03, P < 0.01) with 7/8 as optimal cut-off (Sn 0.71, Sp 1.00) respectively. In multivariate analysis, age was associated with 0.05 (95% CI -0.10-0.00, P < 0.04) point decrement, while >6 years of education was associated with 0.82 (95% CI 0.32-1.33, P < 0.01) point increment in RCS scores.

CONCLUSION

The three-item RCS is quick and easy to administer. Although RCS met the criterion for good validity against MoCA in predicting cognitive impairment, its utility as a first-line screening tool needs to be further validated in a large-scale population study.

Immune-Mediated Diseases from the Point of View of Psychoneuroimmunoendocrinology

Immune-mediated inflammatory diseases (IMIDs) represent a large group of diseases (Crohn's, ulcerative colitis, psoriasis, lupus, and rheumatoid arthritis) evidenced by systemic inflammation and multiorgan involvement. IMIDs result in a reduced quality of life and an economic burden for individuals, health care systems, and countries. In this brief descriptive review, we will focus on some of the common biological pathways of these diseases from the point of view of psychoneuroimmunoendocrinology (PNIE). PNIE consists of four medical disciplines (psychology, nervous system, immune system, and endocrine system), which are key drivers behind the health-disease concept that a human being functions as a unit. We examine these drivers and emphasize the need for integrative treatments that addresses the disease from a psychosomatic point of view.

The Potential Role of Myokines/Hepatokines in the Progression of Neuronal Damage in Streptozotocin and High-Fat Diet-Induced Type 2 Diabetes Mellitus Mice

Background: Diabetes is highly prevalent, and the number of patients with diabetic sarcopenia and cognitive impairment has grown, leading to decreased quality of life. Although the exact mechanisms between sarcopenia and cognitive impairment have not been elucidated, it is speculated that muscle and liver-derived mediators might contribute to brain function. This study examined the molecular mechanisms associated with muscle-brain interaction accompanied by insulin resistance (IR) caused by aberrant energy metabolism via myokines/hepatokines in type 2 diabetes mellitus (T2DM) mice. Methods: T2DM was induced by a high-fat diet and streptozotocin injection. Behavior tests were conducted to analyze grip strength and cognitive function. Histopathological changes in skeletal muscle and brain tissue were examined by hematoxylin and eosin staining and the protein levels of biomarkers related to energy metabolism via myokines/hepatokines were measured by western blot. Results: T2DM caused peripheral and central IR. Furthermore, T2DM led to aberrant energy metabolism through the reduced fibroblast growth factor 21 dependent AMP-activated kinase (AMPK)/surtuin1/proliferator-activated receptor γ coactivator-1α pathway in T2DM. Subsequently, reduced circulating myokines/hepatokines were in accordance with their levels with hippocampal neuronal markers in T2DM mice. Accordingly, skeletal muscle (muscle strength: 2.83 ± 0.39 vs. 2.187 ± 0.51, p = 0.004) and brain function (PAT: 38.5 ± 57.91 vs. 11.556 ± 12.03, p = 0.02) impairment and morphological changes (muscle cross-sectional area: 872.43 ± 242.87 vs. 743.68 ± 169.31, p = 0.01; density of neurons in hippocampus: 145 ± 15.13 vs. 77 ± 35.51, p = 0.05; density of neurons in cortex: 138.333 ± 6.66 vs. 78 ± 17.35, p = 0.05) were shown in T2DM mice. In addition, the working ability demonstrated by Y-maze was positively correlated with % lean mass (p = 0.046, R = 0.3426). Conclusions: T2DM led to aberrant energy in skeletal muscle and brain via myokines/hepatokines. This study suggested that myokines and hepatokines might have potential roles in skeletal muscle and central metabolic functions which can mediate cognitive function in T2DM mice.

HIGH-INTENSITY EXERCISE IMPROVES THE CLINICAL RESPONSE OF ORGAN FUNCTION

ABSTRACT Introduction: Physical activity is accomplished by the coordination of various organ systems of the human body, and physical exercise can positively impact the activities of many of these systems. Because the impact of high-intensity sports on human organs is different according to the environmental temperature and exercise intensity, we must make more detailed observations and discussions. Objective: To analyze the changes in the body shape, function, and organ function of middle school students before and after high-intensity physical exercise through the study of human movement. Methods: Through the experimental research on the characteristics of metabolic gas exchanges in high-intensity incremental load exercise of college students. Results: There were statistically significant differences in the incidence of physiological reactions shown by the students who underwent high-intensity incremental load exercise, such as abdominal pain, dyspnea, tachycardia, nausea, dizziness, and muscle aches (P<0.05). Hypothermia was accompanied by a decrease in heart rate during exercise. Conclusion: Carrying out overload training can effectively mediate physiological functions. It is an important, in improving sports performance, to carry out warm-up activities in a low-temperature environment to increase body temperature. Level of evidence II; Therapeutic studies - investigation of treatment results.

Investigation of Brain Function-Related Myokine Secretion by Using Contractile 3D-Engineered Muscle

Brain function-related myokines, such as lactate, irisin, and cathepsin B (CTSB), are upstream factors that control brain-derived neurotrophic factor (BDNF) expression and are secreted from skeletal muscle by exercise. However, whether irisin and CTSB are secreted by muscle contraction remains controversial. Three-dimensional (3D)-engineered muscle (3D-EM) may help determine whether skeletal muscle contraction leads to the secretion of irisin and CTSB, which has never been identified with the addition of drugs in conventional 2D muscle cell cultures. We aimed to investigate the effects of electrical pulse stimulation (EPS)-evoked muscle contraction on irisin and CTSB secretion in 3D-EM. The 3D-EM, which consisted of C2C12 myoblasts and type-1 collagen gel, was allowed to differentiate for 2 weeks and divided into the control and EPS groups. EPS was applied at 13 V, 66 Hz, and 2 msec for 3 h (on: 5 s/off: 5 s). Irisin and CTSB secretion into the culture medium was measured by Western blotting. Irisin secretion was significantly increased following EPS (p < 0.05). However, there was no significant difference in CTSB secretion between the two groups. The present study suggests that irisin may be a contractile muscle-derived myokine, but CTSB is not secreted by EPS-evoked muscle contractile stimulation in 3D-EM.

Influence of Nutritional Status and Physical Exercise on Immune Response in Metabolic Syndrome

Metabolic Syndrome (MetS) is a cluster of metabolic alterations mostly related to visceral adiposity, which in turn promotes glucose intolerance and a chronic systemic inflammatory state, characterized by immune cell infiltration. Such immune system activation increases the risk of severe disease subsequent to viral infections. Strong correlations between elevated body mass index (BMI), type-2-diabetes and increased risk of hospitalization after pandemic influenza H1N1 infection have been described. Similarly, a correlation between elevated blood glucose level and SARS-CoV-2 infection severity and mortality has been described, indicating MetS as an important predictor of clinical outcomes in patients with COVID-19. Adipose secretome, including two of the most abundant and well-studied adipokines, leptin and interleukin-6, is involved in the regulation of energy metabolism and obesity-related low-grade inflammation. Similarly, skeletal muscle hormones—called myokines—released in response to physical exercise affect both metabolic homeostasis and immune system function. Of note, several circulating hormones originate from both adipose tissue and skeletal muscle and display different functions, depending on the metabolic context. This review aims to summarize recent data in the field of exercise immunology, investigating the acute and chronic effects of exercise on myokines release and immune system function.

Genetic variation of putative myokine signaling is dominated by biological sex and sex hormones

Skeletal muscle plays an integral role in coordinating physiological homeostasis, where signaling to other tissues via myokines allows for coordination of complex processes. Here, we aimed to leverage natural genetic correlation structure of gene expression both within and across tissues to understand how muscle interacts with metabolic tissues. Specifically, we performed a survey of genetic correlations focused on myokine gene regulation, muscle cell composition, cross-tissue signaling, and interactions with genetic sex in humans. While expression levels of a majority of myokines and cell proportions within skeletal muscle showed little relative differences between males and females, nearly all significant cross-tissue enrichments operated in a sex-specific or hormone-dependent fashion; in particular, with estradiol. These sex- and hormone-specific effects were consistent across key metabolic tissues: liver, pancreas, hypothalamus, intestine, heart, visceral, and subcutaneous adipose tissue. To characterize the role of estradiol receptor signaling on myokine expression, we generated male and female mice which lack estrogen receptor α specifically in skeletal muscle (MERKO) and integrated with human data. These analyses highlighted potential mechanisms of sex-dependent myokine signaling conserved between species, such as myostatin enriched for divergent substrate utilization pathways between sexes. Several other putative sex-dependent mechanisms of myokine signaling were uncovered, such as muscle-derived tumor necrosis factor alpha (TNFA) enriched for stronger inflammatory signaling in females compared to males and GPX3 as a male-specific link between glycolytic fiber abundance and hepatic inflammation. Collectively, we provide a population genetics framework for inferring muscle signaling to metabolic tissues in humans. We further highlight sex and estradiol receptor signaling as critical variables when assaying myokine functions and how changes in cell composition are predicted to impact other metabolic organs.

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.

Sarcopenia and motoric cognitive risk syndrome: a moderated mediation model

Background

Sarcopenia has been identified as a risk factor for cognitive impairment, and motoric cognitive risk syndrome (MCR) is a recently defined pre-dementia syndrome. It is not known whether they are related. We aimed to investigate the association and potential pathways between sarcopenia and MCR in the community elderly by establishing a moderated mediation model.

Methods

846 community residents aged ≥ 60 years were recruited from May 2021 to September 2021 and had a comprehensive geriatric evaluation. The diagnosis of sarcopenia followed the criteria issued by the Asian Working Group for Sarcopenia in 2019. MCR was defined as subjective cognitive decline and slow gait. Apathy symptoms and physical activity were assessed by the Apathy Evaluation Scale (AES) and the International Physical Activity Questionnaire (IPAQ). Logistic regression and moderated mediation analyses were conducted to explore the association between the four.

Results

60 (7.1%) had MCR among 846 participants. After full adjustment, sarcopenia (odds ratio [OR] = 3.81, 95% confidence interval [CI] = 1.69–8.60, P = 0.001), AES score (OR = 1.09, 95% CI = 1.04–1.14, P < 0.001), and IPAQ level (OR = 0.43, 95% CI = 0.28–0.66, P < 0.001) were associated with MCR. Apathy partially mediated the relationship between sarcopenia and MCR. Physical activity played a moderation role in the indirect pathway of the mediation model. The increase in physical activity can alleviate the indirect effect of sarcopenia on MCR.

Conclusion

We established a moderated mediation model to uncover the underlying association mechanism of sarcopenia and MCR preliminarily. These findings suggest that attention should be paid to the management of apathy and physical activity in the context of sarcopenia to prevent early dementia actively. Further validation is needed in future longitudinal studies.

Muscle Strength Moderates the Relationship between Nutritional Health Risk and Depression in Korean Older Adults

Background: Little is known about the relationships between muscle strength and nutritional health risk with late-in-life depression. This study aimed to investigate the moderating effect of lower-extremity muscle strength on the relationship between nutritional health risk and depression in Korean older adults. Methods: Data obtained from 5949 women and 3971 men aged ≥ 65 years in the 2020 Korea Longitudinal Study on Aging were used in this study. Exposures included lower-extremity muscle strength and nutritional health risk. Lower-extremity muscle strength was measured with a modified sit-to-stand test. The nutritional health risk was assessed using a screening tool. Depression was defined as a score ≥ 8 points on the Geriatric Depression Scale (GDS). Results: Logistic regression analyses showed that depression was positively associated with nutritional health risk (p < 0.001) and inversely associated with lower-extremity muscle strength (p < 0.001). A moderation analysis with Andrew Hayes’ PROCESS macro showed a significant moderating effect of lower-extremity muscle strength (β = −0.119; 95% confidence interval, −0.172 to −0.066; p < 0.001) on the relationship between nutritional health risk and depression; the weaker was the muscle strength, the steeper was the slope of the GDS score for nutritional health risk. Conclusions: The current findings suggest the need for an intervention targeting both high nutritional risk and weak muscle strength as a therapeutic strategy against depression in Korean older adults.

Resistance training improves cognitive function in older adults with different cognitive status: a systematic review and Meta-analysis

The present study investigated the impact of resistance training (RT) on cognitive function in older adults with different cognitive status by conducting a systematic review and meta-analysis of intervention studies. We performed a literature search with no restriction on publication year in MEDLINE, Embase, CINAHL, SPORTDiscus, and AgeLine from inception up to August 2020. Experimental studies investigating the impact of RT on the cognitive function of cognitively healthy (CH) and cognitively impaired (CI) older adults (≥60 years) were included for analysis. Eighteen studies were included in the final analysis, of which ten studies investigated CH community-dwelling older adult, seven studies investigated CI older adults, and one study investigated both. RT significantly improved overall cognitive function in both CH (SMD = 0.54; 95% CI = 0.00 to 1.08, P = 0.047) and CI (SMD = 0.60; 95% CI = 0.21 to 1.16, P = 0.005) older adults. However, short-term memory was only improved in CH older adults (MD = -0.20; 95% CI = -0.25 to -0.15, P < 0.00001). In conclusion, RT improved overall cognitive function in CH and CI older adults, whereas short-term memory, assessed by the digit span of the WAIS III, was only significantly improved in CH older adults.

Exercise Training Improves Memory Performance in Older Adults: A Narrative Review of Evidence and Possible Mechanisms

As human life expectancy increases, cognitive decline and memory impairment threaten independence and quality of life. Therefore, finding prevention and treatment strategies for memory impairment is an important health concern. Moreover, a better understanding of the mechanisms involved underlying memory preservation will enable the development of appropriate pharmaceuticals drugs for those who are activity limited. Exercise training as a non-pharmacological tool, has been known to increase the mean lifespan by maintaining general body health and improving the cardiovascular and nervous systems function. Among different exercise training protocols, aerobic exercise has been reported to prevent the progression of memory decline, provided adequate exertion level, duration, and frequency. Mechanisms underlying exercise training effects on memory performance have not been understood yet. Convergent evidence suggest several direct and indirect mechanisms at molecular and supramolecular levels. The supramolecular level includes improvement in blood circulation, synaptic plasticity and neurogenesis which are under controls of complex molecular signaling of neurotransmitters, neurotrophic factors, exerkines, and epigenetics factors. Among these various factors, irisin/BDNF signaling seems to be one of the important mediators of crosstalk between contracted skeletal muscles and the brain during exercise training. This review provides an affordable and effective method to improve cognitive function in old ages, particularly those who are most vulnerable to neurodegenerative disorders.

Brothers in arms: proBDNF/BDNF and sAPPα/Aβ-signaling and their common interplay with ADAM10, TrkB, p75NTR, sortilin, and sorLA in the progression of Alzheimer's disease

Brain-derived neurotrophic factor (BDNF) is an important modulator for a variety of functions in the central nervous system (CNS). A wealth of evidence, such as reduced mRNA and protein level in the brain, cerebrospinal fluid (CSF), and blood samples of Alzheimer's disease (AD) patients implicates a crucial role of BDNF in the progression of this disease. Especially, processing and subcellular localization of BDNF and its receptors TrkB and p75 are critical determinants for survival and death in neuronal cells. Similarly, the amyloid precursor protein (APP), a key player in Alzheimer's disease, and its cleavage fragments sAPPα and Aβ are known for their respective roles in neuroprotection and neuronal death. Common features of APP- and BDNF-signaling indicate a causal relationship in their mode of action. However, the interconnections of APP- and BDNF-signaling are not well understood. Therefore, we here discuss dimerization properties, localization, processing by α- and γ-secretase, relevance of the common interaction partners TrkB, p75, sorLA, and sortilin as well as shared signaling pathways of BDNF and sAPPα.

Spontaneous Physical Activity in Obese Condition Favours Antitumour Immunity Leading to Decreased Tumour Growth in a Syngeneic Mouse Model of Carcinogenesis

Simple Summary

With aging, a deterioration of the immune system, termed immunosenescence, leads to a loss of innate and adaptive immunity in terms of number of cells and functionality. This results in an imbalance between pro- and anti-tumour immune response. The aim of the study was to explore the impact of physical activity on the tissue environment in a murine model of breast carcinogenesis. In this model, spontaneous physical activity slows tumour growth by decreasing low-grade inflammation and promotes antitumour immunity.

Abstract

Our goal was to evaluate the effect of spontaneous physical activity on tumour immunity during aging. Elderly (n = 10/group, 33 weeks) ovariectomized C57BL/6J mice fed a hyperlipidic diet were housed in standard (SE) or enriched (EE) environments. After 4 weeks, orthotopic implantation of syngeneic mammary cancer EO771 cells was performed to explore the immune phenotyping in the immune organs and the tumours, as well as the cytokines in the tumour and the plasma. EE lowered circulating myostatin, IL-6 and slowed down tumour growth. Spleen and inguinal lymph node weights reduced in relation to SE. Within the tumours, EE induced a lower content of lymphoid cells with a decrease in Th2, Treg and MDCS; and, conversely, a greater quantity of Tc and TAMs. While no change in tumour NKs cells occurred, granzyme A and B expression increased as did that of perforin 1. Spontaneous physical activity in obese conditions slowed tumour growth by decreasing low-grade inflammation, modulating immune recruitment and efficacy within the tumour.

Muscle-brain communication in pain: The key role of myokines

Pain is the most common reason for a physician visit, which accounts for a considerable proportion of the global burden of disease and greatly affects patients' quality of life. Therefore, there is an urgent need to identify new therapeutic targets involved in pain. Exercise-induced hypoalgesia (EIH) is a well known phenomenon observed worldwide. However, the available evidence demonstrates that the mechanisms of EIH remain unclear. One of the most accepted hypotheses has been the activation of several endogenous systems in the brain. Recently, the concept that the muscle acts as a secretory organ has attracted increasing attention. Proteins secreted by the muscle are called myokines, playing a critical role in communicating with other organs, such as the brain. This review will focus on several myokines and discuss their roles in EIH.

Longitudinal association of sarcopenia and mild cognitive impairment among older Mexican adults

BACKGROUND

Recent evidence from cross-sectional and longitudinal studies supports the hypothesis that sarcopenia is associated with worsening cognitive function. However, primary evidence largely comes from high-income countries, whereas in low- and middle-income countries, this association has been underexplored. This study aimed to estimate the longitudinal association between sarcopenia and mild cognitive impairment in a sample of older Mexican adults.

METHODS

Data come from the three waves of the World Health Organization (WHO) Study on Global AGEing and Adult Health (SAGE) in Mexico (2009, 2014, 2017). Four hundred ninety-six older adults, aged ≥50, were included. Sarcopenia was defined as having low muscle quantity and either/both slow gait speed and weak handgrip strength. Mild cognitive impairment was determined based on the recommendations of the National Institute on Aging-Alzheimer's Association. Cognitive function was evaluated by a composite cognitive score of five different cognitive tests: immediate and delayed recall, forward and backward digit span and semantic verbal fluency. Three-level mixed-effects models (logistic and linear) were used to estimate the longitudinal associations between sarcopenia, mild cognitive impairment and cognitive function.

RESULTS

The prevalence of mild cognitive impairment (8.9%, 12.9%, 16.0%) and sarcopenia (10.5%, 20.7%, 23.3%) showed a significant temporal increase for Waves 1, 2 and 3 (P-value < 0.01, respectively). The presence of sarcopenia was significantly associated with mild cognitive impairment (OR = 1.74; CI95% 1.02, 2.96; P = 0.04) and worse cognitive function (β = -0.57; CI95% -0.93, -0.21; P < 0.01). We observed significant associations between sarcopenia and immediate verbal recall (β = -0.14; CI95% -0.28, -0.01; P = 0.04), delayed verbal recall (β = -0.12; CI95% -0.23, -0.01; P = 0.03) and semantic verbal fluency (β = -0.17; CI95% -0.28, -0.05; P = 0.01). The prevalence of mild cognitive impairment increased at an annual rate of 0.8% for non-sarcopenic older adults, but nearly 1.5% for sarcopenic adults.

CONCLUSIONS

Significant longitudinal associations were observed between sarcopenia, mild cognitive impairment and cognitive function among older Mexican adults. Public health strategies, including policy research and clinical interventions, must be implemented in low- and middle-income countries in order to reduce or delay the onset of sarcopenia and thus improve population-level cognitive health among older adults.

Skeletal muscle atrophy-induced hemopexin accelerates onset of cognitive impairment in Alzheimer's disease

BACKGROUND

Alzheimer's disease (AD) is an unmet medical need worldwide, and physical inactivity is a risk factor for AD. Performing physical exercise is difficult at old age, and thus, decline in physical movement may be a cause of age-associated lowering of the brain function. This study aimed to elucidate the molecular mechanism and onset of the skeletal muscle atrophy-induced acceleration of AD.

METHODS

Pre-symptomatic young 5XFAD or non-transgenic wildtype mice were used. The bilateral hindlimbs were immobilized by placing them in casts for 14 days. Cognitive function was evaluated using the object recognition and spatial memory tests. Further, the hindlimb muscles were isolated for organ culture. Conditioned media (CM) of each muscle was separated by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). Protein expressions in the CM were analysed by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry analysis. The expression levels of candidate proteins were quantified using ELISA. After continuous intracerebroventricular (i.c.v.) infusion of recombinant hemopexin, cognitive function was evaluated. Gene microarray analysis of the hippocampus was performed to investigate the molecules involved in the accelerated memory deficit. Real-time reverse transcription polymerase chain reaction and histological analysis confirmed the expression.

RESULTS

Casting for 2 weeks reduced skeletal muscle weight. Object recognition memory in the cast-attached 5XFAD mice (n = 7, training vs. test, P = 0.3390) was impaired than that in age-matched wildtype (n = 7, training vs. test, P = 0.0523) and non-cast 5XFAD mice (n = 7, training vs. test, P = 0.0473). On 2D-PAGE, 88 spots were differentially expressed in muscle CM. The most increased spot in the cast-attached 5XFAD CM was hemopexin. Hemopexin levels in the skeletal muscle (n = 3, P = 0.0064), plasma (n = 3, P = 0.0386), and hippocampus (n = 3, P = 0.0164) were increased in cast-attached 5XFAD mice than those in non-cast 5XFAD mice. Continuous i.c.v. infusion of hemopexin for 2 weeks induced memory deficits in young 5XFAD mice (n = 4, training vs. test, P = 0.6764). Lipocalin-2 (Lcn2) messenger RNA (mRNA), neuroinflammation-associated factor, was increased in the hippocampus in hemopexin-infused 5XFAD mice than in control mice. LCN2 protein in the hippocampus was localized in the neurons, but not glial cells. Lcn2 mRNA levels in the hippocampus were also increased by cast-immobilization of the hindlimbs (n = 6, P = 0.0043).

CONCLUSIONS

These findings provide new evidence indicating that skeletal muscle atrophy has an unbeneficial impact on the occurrence of memory impairment in young 5XFAD mice, which is mediated by the muscle secreted hemopexin.

Could Irisin Levels be Affected by Physical Activity in Patients with Schizophrenia?

OBJECTIVE

The aim of this study was to explore the effect of physical activity and metabolic parameters on irisin levels in patients with schizophrenia and healthy controls.

METHODS

Ninety-six patients with schizophrenia and 63 healthy controls comprised the study population. The participants were separated into three groups: inactive, low activity, and sufficiently active according to International Physical Activity Questionnaire short form (IPAQ-SF). We measured irisin levels using Enzyme linked immunosorbent assay. We also calculated exercise levels by using the IPAQ-SF for each individual. The independent samples ttest was used in the data analysis to compare irisin levels according to the activity levels of the patients with schizophrenia and controls.

RESULTS

The levels of irisin were higher in the healthy controls (p < 0.001) compared to schizophrenia groups. When the activity levels of the schizophrenia and healthy control groups were compared, the irisin levels of the low activity and sufficiently active groups with schizophrenia were found to be lower than those of the low activity and sufficiently active groups in the healthy controls (respectively p = 0.014; p < 0.001).

CONCLUSION

Irisin levels could be affected by physical activity and these results must be supported with new studies.

Comparison of the effects of open vs. closed skill exercise on the acute and chronic BDNF, IGF-1 and IL-6 response in older healthy adults

BACKGROUND

Accumulating evidence shows that physical exercise has a positive effect on the release of neurotrophic factors and myokines. However, evidence regarding the optimal type of physical exercise for these release is still lacking. The aim of this study was to assess the acute and chronic effects of open-skill exercise (OSE) compared to closed-skill exercise (CSE) on serum and plasma levels of brain derived neurotrophic factor (BDNFS, BDNFP), and serum levels of insulin like growth factor 1 (IGF-1), and interleukin 6 (IL-6) in healthy older adults.

METHODS

To investigate acute effects, thirty-eight participants were randomly assigned to either an intervention (badminton (aOSE) and bicycling (aCSE), n  = 24, 65.83 ± 5.98 years) or control group (reading (CG), n  = 14, 67.07 ± 2.37 years). Blood samples were taken immediately before and 5 min after each condition. During each condition, heart rate was monitored. The mean heart rate of aOSE and aCSE were equivalent (65 ± 5% of heart rate reserve). In a subsequent 12-week training-intervention, twenty-two participants were randomly assigned to either a sport-games (cOSE, n  = 6, 64.50 ± 6.32) or a strength-endurance training (cCSE, n  = 9, 64.89 ± 3.51) group to assess for chronic effects. Training intensity for both groups was adjusted to a subjective perceived exertion using the CR-10 scale (value 7). Blood samples were taken within one day after the training-intervention.

RESULTS

BDNFS, BDNFP, IGF-1, and IL-6 levels increased after a single exercise session of 30 min. After 12 weeks of training BDNFS and IL-6 levels were elevated, whereas IGF-1 levels were reduced in both groups. However, only in the cOSE group these changes were significant. We could not find any significant differences between the exercise types.

CONCLUSION

Our results indicate that both exercise types are efficient to acutely increase BDNFS, BDNFP, IGF-1 and IL-6 serum levels in healthy older adults. Additionally, our results tend to support that OSE is more effective for improving basal BDNFS levels after 12 weeks of training.