Effects of home-based bench step exercise on inflammatory cytokines and lipid profiles in elderly Japanese females: A randomized controlled trial

The effects of aerobic exercise training on inflammatory markers in adult tobacco smokers: A systematic review and meta-analysis of randomized controlled trials

INTRODUCTION

Aerobic exercise training may reduce systemic inflammation, but the effects of this on systemic inflammatory markers in adult tobacco smokers has not been systematically reviewed. Therefore, we evaluated the effects of aerobic exercise training on C-reactive protein (CRP) and tumor necrosis factor-α (TNF-α) in adult tobacco smokers using a systematic review and meta-analysis of randomized controlled trials.

METHODS

A comprehensive literature search was carried out using PubMed/Medline, Web of Science, EMBASE, Google Scholar, and hand search of bibliographies of the retrieved English or Persian articles up to August 2023. This review only included randomized controlled trials which investigated the effect of aerobic exercise training on CRP and TNF-α in adult smokers, based on a predefined inclusion and exclusion criteria.

RESULTS

A total of 1641 articles were identified. Six studies were included in the review and four evaluated CRP and two evaluated TNF-α in only males. The meta-analysis demonstrated that aerobic exercise training significantly decreased TNF-α concentrations in males (MD = -6.68, 95 % CI = -13.90 to -0.54, P = 0.05). CRP concentrations did not decrease significantly when the data from the four studies were pooled (MD = -0.17, 95 % CI = -0.37 to 0.03, P = 0.09).

CONCLUSION

Aerobic exercise training may reduce the concentration of TNF-α in male smokers, but it does not have a significant effect on CRP concentrations. However, these findings are based upon a small number of studies, that enrolled either exclusively male or female participants, and further investigation is necessary to increase statistical inference.

Interleukin-15 responses to acute and chronic exercise in adults: a systematic review and meta-analysis

Purpose

Interlukin-15 (IL-15) is an inflammatory cytokine that plays a vital role in immunology and obesity-associated metabolic syndrome. We performed this systematic review and meta-analysis to investigate whether exercise promotes circulating IL-15 concentrations in adults.

Methods

We searched PubMed, Web of Science, and Scopus from inception to May, 2023 and identified original studies that investigated the effectiveness of acute and/or chronic exercise on serum/plasma IL-15 levels in adults. Standardized mean differences (SMD) and 95% confidence intervals (CI) were calculated using random effect models. Subgroup analyses were performed based on type of exercise, and training status, health status and body mass indexes (BMI) of participants.

Results

Fifteen studies involving 411 participants and 12 studies involving 899 participants were included in the acute and chronic exercise analyses, respectively. Our findings showed that acute exercise increased circulating IL-15 concentrations immediately after exercise compared with baseline [SMD=0.90 (95% CI: 0.47 to 1.32), p=0.001], regardless of exercise type and participants' training status. Similarly, acute exercise was also associated with increased IL-15 concentrations even one-hour after exercise [SMD=0.50 (95% CI: 0.00 to 0.99), p=0.04]. Nevertheless, chronic exercise did not have a significant effect on IL-15 concentrations [SMD=0.40 (95% CI: -0.08 to 0.88), p=0.10].

Conclusion

Our results confirm that acute exercise is effective in increasing the IL-15 concentrations immediately and one-hour after exercise intervention, and thereby playing a potential role in improving metabolism in adults.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=445634, identifier CRD42023445634.

Long-term exercise training and inflammatory biomarkers in healthy subjects: a meta-analysis of randomized controlled trials

Objective

This meta-analysis investigated the effect of long-term exercise training (ET) including aerobic, resistance, and multicomponent ET on the levels of inflammatory biomarkers in randomized controlled trials (RCTs) involving healthy subjects.

Methods

We searched seven databases for articles until May 1st, 2023. A random-effect meta-analysis, subgroup analysis, meta-regressions as well as trim and fill method were conducted using STATA 16.0.

Result

Thirty-eight studies were included in the meta-analysis, involving 2,557 healthy subjects (mean age varies from 21 to 86 years). Long-term ET induced significantly decreased in the levels of interleukin-6 (IL-6) (SMD -0.16, 95% CI -0.30 to -0.03, p = 0.017), C-reactive protein (CRP) (SMD -0.18, 95% CI -0.31 to -0.06, p = 0.005), as well as tumor necrosis factor alpha (TNFα) (SMD -0.43, 95% CI -0.62 to -0.24, p < 0.001). Subgroup analysis revealed that Long-term ET conducted for more than 12 weeks and exercise of moderate intensity had greater anti-inflammatory effects. Meta-regression analysis showed that the reduction in CRP level induced by long-term ET was weakened by increasing exercise intensity.

Conclusion

Long-term ET induced significant anti-inflammatory effects in healthy subjects. Long-term ET-induced anti-inflammatory effects were associated with exercise of moderate intensity and training conducted for more than 12 weeks.Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/# myprospero, PROSPERO, identifier CRD42022346693.

Differential Roles of Neural Integrity, Physical Activity and Depression in Frailty: Sex-Related Differences

The frailty sex paradox has recently gained attention. At all ages, females are more likely to be frail and show a more severe phenotype but have a higher survival rate compared to males. The main aim was to test sex-specific differences in frailty syndrome using a multimodal evaluation from clinical and imaging data to deepen the understanding of different underlying mechanisms involved in the two sexes, and thus understand the association with different risk factors. Ninety-six community-dwelling older adults were characterized by clinical underpinnings (Fried's frailty indicators: comorbidity, depression, global cognitive level, physical activity, autonomy), and neural integrity (T1-weighted brain 3T MRI). The frailty × sex interaction in clinical and neural profiles was tested. Additionally, frailty risk factors were identified in the two sexes separately. Results showed that fragility was associated with an increment of depressive symptomatology in females, while a decrement in physical activity was observed already in the pre-frail stage in males. Finally, different risk factors were observed in the two groups: significant frailty predictors were neural integrity and physical activity in males, and age and depression in females. These data support the starting hypothesis of at least partially different mechanisms involved in the frailty phenotype between men and women.

Energy metabolism and frailty: The potential role of exercise-induced myokines - A narrative review

Frailty is a complex condition that emerges from dysregulation in multiple physiological systems. Increasing evidence suggests the potential role of age-related energy dysregulation as a key driver of frailty. Exercise is considered the most efficacious intervention to prevent and even ameliorate frailty as it up-tunes and improves the function of several related systems. However, the mechanisms and molecules responsible for these intersystem benefits are not fully understood. The skeletal muscle is considered a secretory organ with endocrine functions that can produce and secrete exercise-related molecules such as myokines. These molecules are cytokines and other peptides released by muscle fibers in response to acute and/or chronic exercise. The available evidence supports that several myokines can elicit autocrine, paracrine, or endocrine effects, partly mediating inter-organ crosstalk and also having a critical role in improving cardiovascular, metabolic, immune, and neurological health. This review describes the current evidence about the potential link between energy metabolism dysregulation and frailty and provides a theoretical framework for the potential role of myokines (via exercise) in counteracting frailty. It also summarizes the physiological role of selected myokines and their response to different acute and chronic exercise protocols in older adults.

The effects of ageing, BMI and physical activity on blood IL-15 levels: A systematic review and meta-analyses

AIM

The purpose of the study was to test the effect of ageing, BMI, physical activity and chronic exercise on IL-15 blood concentration by meta-analyses of the literature.

METHODS

The search was performed on PubMed/MEDLINE, Web of Science, ProQuest, Embase and Cochrane databases. First meta-analysis compared blood IL-15 of healthy adults across three age groups (<35 years, 35-65 years, and >65 years), considering BMI as confounding factor; the second compared IL-15 levels between physically active and non-physically active individuals (cross-sectional studies); and the third tested the effect of chronic exercise interventions on blood IL-15 levels on participants of any age, sex, and health condition.

RESULTS

From 2582 studies retrieved, 67 were selected for the three meta-analyses (age effect: 59; physical activity cross-sectional effect: 5; chronic exercise effect: 14). Older adults had lower blood IL-15 than young and middle-aged adults (5.30 pg/ml [4.76; 5.83]; 7.11 pg/ml [6.33; 7.88]; 7.10 pg/ml [5.55; 8.65], respectively). However, the subgroup of overweight older adults had higher IL-15 than young and middle aged overweight adults; Habitual physical activity did not affect blood IL-15 (standardized mean difference [SMD] 0.61 [-0.65; 1.88], p = 0.34); Chronic exercise reduced blood IL-15 in short-term interventions (<16 weeks) (SMD -0.14 [-0.27; -0.01], p = 0.04), but not studies of >16 weeks of intervention (SMD 0.44 [-0.26; 1.15], p = 0.22).

CONCLUSION

The present meta-analyses highlight the complex interaction of age, BMI and physical activity on blood IL-15 and emphasize the need to take these factors into account when considering the role of this myokine in health throughout life.

Relationship between Measured Aerobic Capacity and Total Energy Expenditure Obtained by the Doubly Labeled Water Method in Community-Dwelling, Healthy Adults Aged 81–94 Years

The doubly labeled water method is a gold-standard method for the measurement of total energy expenditure in daily life. We aimed to identify the relationship between measured aerobic capacity and total energy expenditure, activity energy expenditure, or physical activity level using the doubly labeled water method in adults of advanced old age. A total of 12 physically independent older adults (10 men and 2 women), aged 81–94 years, participated in this study. The aerobic capacity was evaluated according to the lactate threshold. Total energy expenditure under free-living conditions was assessed using the doubly labeled water method, and self-reported physical activity was obtained using the Japanese version of the International Physical Activity Questionnaire. The lactate threshold was significantly positively correlated with total energy expenditure, activity energy expenditure, and physical activity level after adjusting for age and sex. We found that the aerobic capacity of the lactate threshold was positively and independently correlated with total energy expenditure, activity energy expenditure, or physical activity level. The present results suggest that maintaining aerobic capacity is an important factor in preventing frailty, although further research is required.

The Effects of Exercise on Appetite in Older Adults: A Systematic Review and Meta-Analysis

Background: The effect of physical activity and exercise on hunger and satiety has been well-studied in younger adults, but the influence of aging is less understood. While some evidence suggests that acute bouts of exercise induce a compensatory eating drive, long-term activity may improve satiety sensitivity. The objective of this study was to investigate the effects of exercise on appetite in older adults.

Methods: We systematically reviewed available literature investigating the effect of exercise on appetite in older adults adults (CRD42020208953). PubMed, PsycINFO, Academic Search Complete, the Sports Medicine & Education Index, and Web of Science, were searched for peer-reviewed articles published in English with no date restriction. Included studies implemented a primary exercise or physical activity intervention with a control group, on a generally healthy population ≥60 years of age. Selected studies included at least one appetite outcome. Risk of bias was assessed using the 11-point Physiotherapy Evidence Database (PEDro) tool. Standardized mean difference summary statistics (Hedge's g effect sizes) and 95% confidence intervals were reported.

Results: We identified 15 reports (13 studies) which met all inclusion criteria (5 resistance training, 3 aerobic, 6 mixed modalities). Studies included 443 participants (Age = 68.9 ± 5.2, 82.3% female) and had generally “good” bias scores (PEDro = 6.4 ± 0.88). Random effects meta-analyses revealed that the exercising group showed statistically significant reductions in glucose [SMD = −0.34 (95% CI: −0.67, −0.02), p < 0.05, PEDro =6.4 ± 0.45] and leptin [SMD = −0.92 (95% CI: −1.28, −0.57), p < 0.00001, PEDro = 6.2 ± 0.75].

Discussion: This systematic review revealed that exercise and physical activity may modulate resting hunger and satiety in older adults. Decreases in fasting leptin and glucose hormones suggest that exercise promotes satiety sensitivity in adults aged 60+. This review highlights that engaging in exercise and activity programs may provide a meaningful avenue for improving chronic and functional disease burden in later life by promoting appetite control and balanced energy intake. Recommendations for future research include investigations of appetite in response to varied exercise modalities within more diverse and representative samples of older adults.

The effect of exercise training on blood pressure in menopause and postmenopausal women: A systematic review of randomized controlled trials

The prevalence of hypertension is higher in postmenopausal than in premenopausal women. Regular exercise training has been shown to be effective in addressing hypertension. The aim of this systematic review was to synthesize the effect of exercise training on systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) in menopausal and postmenopausal women. This review was reported according to the PRISMA statement and registered in PROSPERO. The literature search was done in MEDLINE, Embase, Cochrane CENTRAL and ClinicalTrials. Randomized controlled trials involving menopausal and postmenopausal women undergoing exercise training were included. Two blinded reviewers assessed risk of bias in the included studies by using the Cochrane Risk of Bias tool. A random-effects model was used for all analyses. Significance was set at P < 0.05. Compared with the control group, exercise training resulted in clinically significant reductions on SBP (MD -3.43 mmHg; 95% CI, -5.16, -1.71; P < 0.0001), DBP (MD, -2.25 mmHg; 95% CI, -3.40, -1.11; P = 0.0001) and MAP (MD, -3.48 mmHg; 95% CI, -5.84, -1.11; P = 0.004). Aerobic training (AT) did not produce a significant reduction in SBP, DBP and MAP (P >0.05). Combined training (CT) generated larger reductions. Exercise training generated small but clinically relevant reductions in SBP, DBP and MAP in menopausal and postmenopausal women, younger or older than 65 years, with prehypertension or hypertension. AT did not lead to a clinically relevant improvement in blood pressure (BP) in this population. In addition, CT showed the largest reductions in SBP, DBP and MAP.

The form of exercise to decrease resting blood pressure in older adults: A systematic review and meta-analysis

BACKGROUND/OBJECTIVES

The current systematic review and meta-analysis evaluated the relationship between the form of exercise and changes in resting blood pressure (RBP) in older adults and the overall level of evidence.

METHODS

The inclusion criteria were studies involving intervention with only regular exercise limited to subjects ≥65 years old. The combined changes in RBP in each study were calculated and the relationship between the form of exercise and changes in the RBP were evaluated. The overall evidence was assessed using the GRADE approach.

RESULTS

Nineteen studies (1081 subjects) were analyzed. The combined changes in the RBP decreased as a result of aerobic exercise or resistance exercise. The intensity of resistance exercise (METs) was related to the change in the RBP of systolic (meta-regression coefficient, -2.5 [95% confidence interval, -4.7 to -0.4]; R²=35.4%). When excluding studies with high overall risk of bias, the overall duration of aerobic exercise (weeks) was related to the change in the RBP of systolic (meta-regression coefficient, -0.6 [95% confidence interval, -1.0 to -0.2]; R²=93.2%). In addition, there was a low level of evidence overall for a decrease in RBP as a result of aerobic exercise, but there was a moderate level of evidence for a decrease in RBP as a results of resistance exercise.

CONCLUSION

A decrease in the RBP of systolic may be associated with active exercise in older adults. However, there may be insufficient evidence for the decrease in RBP as a result of aerobic exercise.

Exercise for slowing the progression of atherosclerotic process: effects on inflammatory markers

Atherosclerosis is a dynamic process driven by all cardiovascular risk factors that can be briefly divided into an early and a late phase. Inflammation is one of the fundamental substrates that initiates the atherosclerotic process in the early stages and promotes and maintains it in the final stages. In the last decades, clinical and experimental data have shown that inflammation is supported by mediators that respond to physical activity. The present review aimed at investigating the effect of physical exercise on inflammatory mediators, both the positive ones that have a proinflammatory effect (interleukin 6, c-reactive protein and tumor necrosis factor α, interferon γ, high-mobility group box-1), and the negative ones which have an anti-inflammatory effect (interleukin 10). Pooled data support the evidence that physical exercise can directly modulate the activity of inflammatory cytokines slowing down or preventing the formation of the atherosclerotic stage.

Effect of Various Exercise Regimens on Selected Exercise-Induced Cytokines in Healthy People

Different forms of physical activity—endurance, resistance or dynamic power—stimulate cytokine release from various tissues to the bloodstream. Receptors for exercise-induced cytokines are present in muscle tissue, adipose tissue, liver, brain, bones, cardiovascular system, immune system, pancreas, and skin. They have autocrine, paracrine and endocrine activities. Many of them regulate the myocyte growth and differentiation necessary for muscle hypertrophy and myogenesis. They also modify energy homeostasis, lipid, carbohydrate, and protein metabolism, regulate inflammation and exchange information (crosstalk) between remote organs. So far, interleukin 6 and irisin have been the best studied exercise-induced cytokines. However, many more can be grouped into myokines, hepatokines and adipomyokines. This review focuses on the less known exercise-induced cytokines such as myostatin, follistatin, decorin, brain-derived neurotrophic factor, fibroblast growth factor 21 and interleukin 15, and their relation to various forms of exercise, i.e., acute vs. chronic, regular training in healthy people.

The effects of exercise interventions on the inflammatory profile of older adults: A systematic review of the recent literature

INTRODUCTION

Inflammageing - characterized by age-related chronic low-grade inflammation is considered to be positively influenced by physical exercises. The aim of this systematic review is to provide an update of the most recent literature regarding exercise effects on the inflammatory profile in older adults.

METHODS

This review is an update of an earlier published literature review and was performed according to the NICE guidelines. Databases PubMed and Web-of-Science were systematically searched by two independent authors screening for papers published since 2016. Effect sizes of outcome parameters related to the inflammatory profile were calculated where possible.

RESULTS & DISCUSSION

Twenty-three articles were included. Resistance training (RT) was the most investigated type of exercise (13 articles: 8 in healthy, 1 in frail and 4 in older adults with a specific condition or disease). Aerobic training (AT) was investigated in 8 articles, including 5 studies in older adults with a specific disease or condition. Combined resistance & aerobic training (CT) was investigated in 7 articles: 3 were in healthy, 1 in frail and 3 in older adults with a specific condition or disease. 1 study investigated the effects of Tai Chi in older adults with mild cognitive impairment. In frail older subjects, IGF-1 - sole marker investigated - significantly increased after 8 weeks RT and CT, whereas AT showed no significant effects compared to control. Most consistent exercise effects consisted in lowering of circulating levels of CRP, IL-6 and TNF-α; which seemed more prominent in healthy older adults compared to those with a specific disease or condition. None of the studies reported an exacerbation of inflammation following exercise and all studied exercise protocols were feasible and safe for older adults.

CONCLUSIONS

Overall, significant anti-inflammatory effects of exercise in older persons were reported. Literature remains extremely scarce regarding the exercise-induced effects in frail older persons. Therefore, there is an urgent need for more studies focusing on the frail elderly. There is growing literature data on exercise interventions in older adults with a specific condition or disease; however, it appears more challenging to reduce inflammageing through exercise in these specific patient groups. Importantly, the exercise interventions performed in all studies appeared to be feasible and safe for older patients, thus the presence of a specific condition or disease should not be considered as a contra-indication to perform physical exercise.

The effect of lifestyle physical activity in reducing cardiovascular disease risk factors (blood pressure and cholesterol) in women: A systematic review

Cardiovascular diseases (CVD) are the most important cause of death in older women. Although there is strong evidence in the literature that moderate lifestyle physical activity (PA) is effective in modifiable CVD risk factors, there is limited evidence demonstrating which activities are effective in women. This systematic review was conducted to evaluate the effect of lifestyle PA interventions on CVD risk factors in women. Various databases were searched for English articles from 2000 to 2019. Eight articles met the selection criteria. It is recommended to use different combinations of interventions including moderate PA, to reduce CVD risk factors in women.

The Beneficial Effect of Physical Exercise on Inflammatory Makers in Older Individuals

Old age is associated with a loss of motor functions and a general progressive decline in cognitive functions. Physical exercise is one of the ways in which inflammatory levels in general can be reduced, and therefore physical exercise can be considered a biological aging decelerator. In this article, we examine the relationships between physical exercise and inflammatory markers reported for the different physical exercise protocols that have been used in studies with older individuals, as well as the effects of these regimens. The different types of exercises programmed, and methods used to implement them were very heterogeneous in the articles we analysed. Both, the aerobic exercise and resistance training protocols produced a decrease in plasma levels of IL-6, CRP and TNF-α, and an increase of IL-10 plasma levels as a chronic effect. However, the acute-response of physical exercise appeared to be an initial increase in IL-6 expression and plasma IL-6 levels. Continuing with these exercise programs usually subsequently achieved a chronic response in which there was a decrease in both the basal levels of IL-6, CRP and TNF-α, and the IL-6 produced as acute responses. Regardless of the type of exercise performed, it seems that the exercise parameters, intensity, duration, subject variables, fitness, and level of inflammation are key factors in achieving the expected balance between proinflammatory and anti-inflammatory cytokines.

A systematic review of aerobic and resistance exercise and inflammatory markers in people with multiple sclerosis

Inflammation is a driver in the demyelination process in patients with multiple sclerosis (MS) and can influence disability levels. Both single and repeated bouts of exercise can decrease inflammatory markers in people with MS (PwMS). This systematic review evaluates whether exercise can influence inflammation and disability in individuals with MS. Experimental studies were reviewed that had to meet the following eligibility requirements: a sample of PwMS, an intervention of exercise (either aerobic, resistance, or a combination of each), and an outcome that included at least one inflammatory (cytokine) reaction. The main outcome measure was an evaluation of inflammation, as indicated by a change in any cytokine level. Other measures included muscle strength, balance, flexibility, walking ability, disability statues, and quality of life (QOL). A total of nine studies were included in the final review. Exercise interventions included predominantly cycling, although a few resistance training trials were mentioned. Small decreases were found in IL-17 and IFN-γ after exercise. Functional outcome measures and perceived disability status were improved posttraining. We conclude that while interventions such as exercise may impact QOL, they do not have a significant influence on inflammation associated with MS. Exercise is an accessible alternative that not only helps to decrease impairments but also limit the restrictions associated with participation in society. While functional outcomes after exercise improved, these improvements may not be attributable to changes in levels of cytokines or inflammatory markers.

Effects of Exercise on Inflammatory, Oxidative, and Neurotrophic Biomarkers on Cognitively Impaired Individuals Diagnosed With Dementia or Mild Cognitive Impairment: A Systematic Review and Meta-Analysis

Although the effects of physical exercise (PE) on cognitive function in dementia and mild cognitive impairment (MCI) have been largely studied, its biochemical effect is still poorly explored. The aim of this systematic review was to investigate the effects of PE on inflammatory, oxidative, and neurotrophic biomarkers of participants with MCI or dementia. Six electronic databases, (PubMed, Cochrane Central, Embase, PEDro, PsycINFO, and SportDiscus) were searched for randomized controlled trials assessing the effects of PE on serum and/or plasma biomarkers of elderly participants with MCI or dementia. After selection process, eight studies were included. Meta-analysis was performed by comparison of changes from baseline, using the random effects method. Meta-analysis showed a significant effect of aerobic exercise on interleukin-6 and tumor necrosis factor alpha decrease and positive effects on brain-derived neurotrophic factor expression. As only one study was included with oxidative biomarker assessment, the effects of PE on oxidative process remain unclear. Finally, even though it was possible to observe positive effects of PE on some biomarkers of MCI and dementia individuals, current evidence does not allow drawing specific practical recommendations such as type, frequency, intensity, or duration of PE in these population. Further researches aiming to estimate the PE effectiveness on biomarkers of MCI and Alzheimer's disease are needed.

The interaction between ABCA1 polymorphism and physical activity on the HDL-cholesterol levels in a Japanese population

Few studies have investigated the interactions between HDL-C-related SNPs identified by genome-wide association (GWA) study and physical activity (PA) on HDL-C. First, we conducted a sex-stratified GWA study in a discovery sample (2,231 men and 2,431 women) and replication sample (2,599 men and 3,109 women) to identify SNPs influencing log-transformed HDL-C in Japanese participants in the baseline survey of the Japan Multi-Institutional Collaborative Cohort Study. We also replicated previously reported HDL-C-related SNPs in a combined (discovery plus replication) sample (4,830 men and 5,540 women). We then analyzed the interactions of the HDL-C-related SNPs with PA on HDL-C. The sex-stratified GWA analyses identified 11 and 10 HDL-C-related SNPs in men and women as targets for an interaction analysis. Among these, only one interaction of ABCA1 rs1883025 with PA was statistically significant in men, after Bonferroni correction [P-interaction = 0.001 (α = 0.05/21 = 0.002)]. The per-major-allele (C allele) increase in log-transformed HDL-C was lost in men with low PA (β = 0.008) compared with those with medium (β = 0.032) or high PA (β = 0.034). These findings suggest that the benefit of carrying a C allele of ABCA1 rs1883025 on enhancing HDL-C may be attenuated in inactive men.

A systematic review of existing peripheral biomarkers of cognitive aging: Is there enough evidence for biomarker proxies in behavioral modification interventions?: An initiative in association with the nutrition, exercise and lifestyle team of the Canadian Consortium on Neurodegeneration in Aging

Peripheral biomarkers have shown significant value in predicting brain health and may serve as a useful proxy measurement in the assessment of evidence-based lifestyle behavior modification programs, including physical activity and nutrition programs, that aim to maintain cognitive function in late life. The aim of this systematic review was to elucidate which peripheral biomarkers are robustly associated with cognitive function among relatively healthy non-demented older adults. Following the standards for systematic reviews (PICO, PRIMSA), and employing MEDLINE and Scopus search engines, 222 articles were included in the review. Based on the review of biomarker proxies of cognitive health, it is recommended that a comprehensive biomarker panel, or biomarker signature, be developed as a clinical end point for behavior modification trials aimed at enhancing cognitive function in late life. The biomarker signature should take a multisystemic approach, including lipid, immune/inflammatory, and metabolic biomarkers in the biological signature index of cognitive health.

Effect of Aerobic Exercise on Inflammatory Markers in Healthy Middle-Aged and Older Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Chronic inflammation plays a significant role in accelerating the aging process and is closely associated with the initiation and progression of a broad range of age-related diseases. Physical exercise is considered beneficial in alleviating these conditions, but the effects of aerobic exercise on inflammatory markers in a healthy population should be furtherly clarified.

Objective: The purpose of this systematic review and meta-analysis was to evaluate the effect of aerobic exercise on inflammatory markers in middle-aged and older adults.

Methods: The literature search was conducted utilizing PubMed, Web of Science, Embase, and the Cochrane Library from their inception through April 2018, and the reference lists were screened to identify appropriate studies. Only randomized controlled trials that investigated the effect of aerobic exercise on inflammatory markers in middle-aged and older adults were eligible for this review.

Results: Eleven studies involving 1,250 participants were retrieved from the databases for analysis. The pooled results showed that aerobic exercise significantly reduced inflammatory markers (C-reactive protein (CRP): SMD = 0.53, 95% CI 0.26–0.11, p = 0.0002; tumor necrosis factor-alpha (TNF-α): SMD = 0.75, 95% CI 0.31–1.19, p = 0.0007; interleukin 6 (IL-6): SMD = 0.75, 95% CI 0.31–1.19, p = 0.0007). No significant improvement was found in relation to interleukin 4 (IL-4).

Conclusions: Aerobic exercise may have a positive effect on reduction of CRP, TNF-α, and IL-6 in middle-aged and older adults. Further randomized controlled trials (RCTs) need to be conducted to determine the effect of aerobic exercise on additional inflammatory markers in the population of middle-aged and older adults.

Mid-arm muscle circumference: A significant factor of all-cause and cancer mortalities in individuals with elevated platelet-to-lymphocyte ratio

Platelet-to-lymphocyte ratio (PLR) is an inflammatory maker, and high PLR is associated with mortality in several diseases. The predictors of mortality in individuals with high PLR is still lacking. Our aims were to assess if mid-arm muscle circumference (MAMC) can predict all-cause mortality, cancer mortality, and cardiovascular mortality in individuals with high PLR. Adult participants from the National Health and Nutrition Examination Survey III (1988–1994) were included. All participants were divided into low PLR and high PLR groups with the cut-off point being the median PLR level, and each group was evaluated for risk factors of mortality. MAMC was divided into tertiles and the general characteristics of the study population related to MAMC were evaluated. The study included 14,221 adults with 6,701 (47.1%) male and 7,520 (52.9%) female participants. The median PLR ratio was 122. Higher levels of systolic blood pressure, total triglycerides, total cholesterol, low-density lipoprotein, C-reactive protein, uric acid, and glucose, as well as a higher age, were associated with increased risk of mortality in both groups. After adjusting for all the covariates, in the higher PLR group, the highest MAMC tertile was significantly associated with lower hazard ratios for all-cause and cancer mortalities compared with the lowest MAMC tertile. However, this association was not observed in the low PLR group. The highest MAMC tertile showed protective effects from all-cause and cancer mortalities compared with the lowest MAMC tertile in individuals with PLR ≥ 122. In conclusion, the highest MAMC tertile was significantly associated with decreasing HRs for all-cause and cancer mortalities compared with the lowest MAMC tertile in individuals with elevated PLR.

Effects of Aerobic Exercise Alone on Lipids in Healthy East Asians: A Systematic Review and Meta-Analysis

AIM

The purpose of the current work was to review the effects of regular aerobic exercise on serum lipid and lipoprotein levels in East Asians using meta-analysis.

METHODS

The randomized controlled trials analyzed involved healthy adults who were East Asians with a mean age ≥40 years, an exercise group that only performed regular aerobic exercise, and a control group that did not carry out exercise-related intervention; the trials indicated mean high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), or triglyceride (TG). The mean difference (MD) was defined as the difference (mean value at post-intervention in the exercise group－mean value at baseline in the exercise group)－(mean value at post-intervention in the control group－mean value at baseline in the control group) in HDL-C, LDL-C, TC, and TG and was calculated for each trial. The weighted MD was calculated with a random-effects model.

RESULTS

The meta-analysis examined 994 subjects in 25 studies. The weighted MD in HDL-C, TC, and TG improved significantly (HDL-C, 2.2 mg/dL; TC, －5.8 mg/dL; TG, －13.7 mg/dL). The weighted MD in HDL-C and TC contained significant heterogeneity (HDL-C, I²＝45.1%; TC, I²＝56.2%). When trials were limited to those involving moderate-intensity exercise (55%-69% of the maximum heart rate) or an exercise volume ≥150 min/week, the weighted MD in HDL-C, LDL-C, TC, and TG improved significantly and did not contain significant heterogeneity.

CONCLUSIONS

The findings suggest that the ideal form of exercise to improve lipid and lipoprotein levels in East Asians is exercise of moderate-intensity and in a volume ≥150 min/week.

Intensity-Specific and Modified Effects of Physical Activity on Serum Adiponectin in a Middle-Aged Population

Context

The effects of intensity-specific physical activity (PA) and its interaction with other lifestyle factors on serum adiponectin are currently unclear.

Objective

To investigate the effects of replacing sedentary time with either light-intensity PA (LPA) or moderate- to vigorous-intensity PA (MVPA) on total and high-molecular-weight (HMW) adiponectin and to examine interactions with smoking, alcohol drinking, coffee consumption, and menopausal status in a general population.

Design/Setting

Cross-sectional study of 4013 men and 6050 women (40 to 69 years of age).

Main Outcome Measures

The associations of replacing sedentary time with LPA or MVPA on total and HMW adiponectin were analyzed using an isotemporal substitution model.

Results

In men, reallocating 60 minutes of sedentary time to 60 minutes of LPA was associated with 9% and 13% higher total and HMW adiponectin levels even after adjusting for confounders, although such associations were not observed for MVPA. A similar pattern of results was also seen in women. The effect of replacing sedentary time with LPA on adiponectin was clearer in middle/high coffee consumers than in low coffee consumers among women. Although increasing the effect of replacing sedentary time with MVPA on adiponectin was clearer in former/current smokers than in never smokers among men, the replacement effect for MVPA on total adiponectin was clearer in premenopausal women than in postmenopausal women.

Conclusions

Replacing sedentary time with LPA resulted in increased levels of total and HMW adiponectin. The replacement effects for LPA or MVPA were found to be multiply modified by smoking, coffee consumption, and menopausal status.

Mid-arm muscle circumference as a substantial factor against mortality among people with elevated gamma gaps

Gamma gap is the difference in total serum proteins and albumin and an elevated gamma gap is related to infections, malignancy, and rheumatic diseases. An elevated gamma gap is also associated with higher mortality due to the correlation with inflammatory status. The study aimed to utilize mid-arm muscle circumference (MAMC) to assist in predicting all-cause mortality, cancer mortality, and cardiovascular mortality in people with elevated gamma gaps. Data were obtained from the third U.S. National Health and Nutrition Examination Survey (1988–1994), which contained 14,011 adults aged 20 to 90 years during up to 14.3 years of follow-up. The Primary analysis examined MAMC in tertiles and revealed the demographic and characteristics of the study population. Receiver operating characteristic curve analysis was used and the most suitable cut-off point of gamma gap was 3.65 g/dl. The secondary analysis employed Cox proportional hazards models stratified by age, gender and body mass index to evaluate the hazard ratios for all-cause mortality, cancer mortality, and cardiovascular mortality associated with the MAMC. As the MAMC tertiles increased in group with gamma gap ≥ 3.65 g/dl, individuals with elder age (60–90 years), normal range of body mass index (19–24.9 kg/m²), and male gender tended to have lower hazard ratios for all-cause mortality, cancer mortality, and cardiovascular mortality. These substantial findings indicate that higher MAMC may be a protective factor of all cause-mortality, cancer mortality, and cardiovascular mortality among older male with normal body mass index and elevated gamma gaps.

Exercise-induced myokines: a brief review of controversial issues of this decade

INTRODUCTION

Myokines, known to mediate metabolism, inflammation, and other pathophysiological conditions, have been widely investigated, including myokines induced by exercise. However, among published literature, there is substantial inconsistency in the quantification of exercise-induced myokines. Here, we summarized and compared published data regarding the effects of exercise on commonly studied myokines including apelin, Brain-derived neurotrophic factor (BDNF), Interleukin-15 (IL-15), irisin, and Secreted protein acidic and rich in cysteine (SPARC) during the last decade and discussed possible reasons for discrepancy in these reports.

AREAS COVERED

A search on PubMed for original articles published in this decade was conducted, focusing on the impacts of exercises on myokines and metabolic and age-related disorders. Beneficial relationship between skeletal muscle plasticity and myokines due to exercise is also discussed.

EXPERT COMMENTARY

Based on these analyses, exercise induces the secretion of a number of myokines, which has positive effects on metabolic diseases or age-related muscle atrophy (sarcopenia). However, among published reports, there is wide discrepancy in the quantification of myokines induced by exercise, which could be due to timing of sample collection, pre-analytic sample processing, analytical method, and calculation and other factors. Thus, these factors need to be considered in future studies on exercise induced myokines.

Current and future therapies for addressing the effects of inflammation on HDL cholesterol metabolism

Cardiovascular disease (CVD) is a major cause of morbidity and mortality worldwide. Inflammatory processes arising from metabolic abnormalities are known to precipitate the development of CVD. Several metabolic and inflammatory markers have been proposed for predicting the progression of CVD, including high density lipoprotein cholesterol (HDL-C). For ~50 years, HDL-C has been considered as the atheroprotective 'good' cholesterol because of its strong inverse association with the progression of CVD. Thus, interventions to increase the concentration of HDL-C have been successfully tested in animals; however, clinical trials were unable to confirm the cardiovascular benefits of pharmaceutical interventions aimed at increasing HDL-C levels. Based on these data, the significance of HDL-C in the prevention of CVD has been called into question. Fundamental in vitro and animal studies suggest that HDL-C functionality, rather than HDL-C concentration, is important for the CVD-preventive qualities of HDL-C. Our current review of the literature positively demonstrates the negative impact of systemic and tissue (i.e. adipose tissue) inflammation in the healthy metabolism and function of HDL-C. Our survey indicates that HDL-C may be a good marker of adipose tissue health, independently of its atheroprotective associations. We summarize the current findings on the use of anti-inflammatory drugs to either prevent HDL-C clearance or improve the function and production of HDL-C particles. It is evident that the therapeutic agents currently available may not provide the optimal strategy for altering HDL-C metabolism and function, and thus, further research is required to supplement this mechanistic approach for preventing the progression of CVD.

LINKED ARTICLES

This article is part of a themed section on Targeting Inflammation to Reduce Cardiovascular Disease Risk. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.22/issuetoc and http://onlinelibrary.wiley.com/doi/10.1111/bcp.v82.4/issuetoc.

Regular aerobic exercise and blood pressure in East Asians: A meta-analysis of randomized controlled trials

The aim of this meta-analysis was to evaluate the effects of regular aerobic exercise on blood pressure in East Asians. The inclusion criteria of the randomized controlled trials were healthy East Asian adults, exercise group performing regular aerobic exercise and control group not exercising, and a description of the mean systolic blood pressure or diastolic blood pressure at rest. This study included 31 study groups and 1994 subjects. Pooled changes in blood pressure showed significant reductions (systolic blood pressure: -4.7 mmHg; diastolic blood pressure: -3.2 mmHg). In subgroup analyses, the change in systolic blood pressure for randomized controlled trials meeting the America Heart Association and American College of Sports Medicine guidelines for physical activity to maintain health was significantly larger than in randomized controlled trials not meeting the guidelines. In addition, meta-regression indicated that the change in systolic blood pressure was significantly related to "exercise time × exercise frequency." The ideal volume of exercise is that for a long time at a high frequency, such as the volume recommended in the America Heart Association and American College of Sports Medicine guidelines: moderate intensity and >150 min per week. List of abbreviations: BP: blood pressure; BMI: body mass index; SBP: systolic blood pressure; DBP: diastolic blood pressure; RCT: randomized controlled trial; AHA: America Heart Association; ACSM: America College of Sports Medicine; SD: standard deviation; HDL-C: high-density lipoprotein cholesterol; LDL-C: low-density lipoprotein cholesterol; TC: total cholesterol; TG: triglycerides; PEDro: Physiotherapy Evidence Database; CI: confidence intervals; %HR_max: percentage of maximal heart rate.

Strength Training Decreases Inflammation and Increases Cognition and Physical Fitness in Older Women with Cognitive Impairment

Introduction: Cognitive impairment that affects older adults is commonly associated with an inflammatory imbalance, resulting in decreased physical fitness. Exercise has been pointed to mitigate immunosenescence and cognitive impairment associated with aging, while increase in physical fitness. However, few studies explored the relationship between changes in cytokine concentration and improvement on cognition due to elastic band strength training. The aim of this study was to investigate the effects of strength training on pro-and anti-inflammatory cytokines, hematological markers and physical fitness of older women with cognitive impairment.

Methods: Thirty-three women (82.7 ± 5.7 years old) participated in the study and were divided in two groups: strength exercise training group (ST; n = 16) and Control Group (CG; n = 17) and were evaluated before and after 28 weeks of the exercise program. The CG did not undergo any type of exercise programs. Data for IL-10, TNF-α, IFN-γ, C-Reactive Protein (CRP), white blood counts (WBC), red blood counts (RBC), Mini Mental State Examination (MMSE) and physical fitness tests were analyzed in both moments.

Results: IL-10 increased in the ST group without changes in CG. TNF-α and CRP increased in the control group while no changes were observed for IFN-γ in both groups. Strength training decreased leukocyte and lymphocyte counts and increase hemoglobin, mean cell volume and mean cell hemoglobin concentration. The MMSE score increased in strength training group but remained unchanged in the control group. A correlation between the variation of granulocyte counts and the MMSE scores was also observed within the total sample. An improvement in physical fitness was observed with strength training.

Conclusion: Resistance exercise promoted better anti-inflammatory balance and physical performance simultaneously with an increase in cognitive profile in older women with cognitive impairment.

Influence of a home-based exercise program on the urine pH in elderly female subjects: a secondary analysis of a randomized controlled trial

Background

A low urine pH is a characteristic metabolic feature of metabolic syndrome and type 2 diabetes. The purpose of the current study was to investigate the effects of a 12-week home-based bench step exercise on the urine pH status of elderly female subjects.

Methods

The current study is a secondary analysis of a randomized controlled trial (RCT) in which 59 postmenopausal female subjects were randomized to either the exercise group (n = 29) or the control group (n = 30). The subjects in the exercise group were instructed to perform home-based exercises using a bench step at the anaerobic threshold (AT), with a goal of performing ≥140 min/week at home for 12 weeks. The subjects in the control group were instructed to not change their normal lifestyle. Urine was collected after overnight fasting, and the urine pH was measured using a urinary test strip. The inter-group-differences at baseline and the pre-post changes within groups were assessed using the Mann-Whitney U test and Wilcoxon’s signed-rank test, respectively. Additionally, the difference in the post-intervention urine pH levels of the two groups, adjusted for the pre-intervention values (the estimated effect size) and the precision (95% confidence intervals) were investigated using an analysis of covariance.

Results

The pre-post comparison of the urine pH data using Wilcoxon’s signed-rank test showed a significant increase in the urine pH levels of the exercise group (p < 0.05); there was no significant change in the urine pH levels of the control group. However, the estimated effect size (0.15) was small and the confidence interval straddled 0 (−0.25–0.55).

Conclusions

Based on the results of the current secondary analysis of an RCT, we could not clearly conclude that exercise has a beneficial effect on the urine pH. Further well-designed RCTs should be conducted to determine whether aerobic exercise is truly able to ameliorate urine acidification.

Trial registration

The study was retrospectively registered in the University Hospital Medical Information Network (UMIN) as “Effect of step exercise on aerobic fitness and progression of atherosclerosis in the elderly” under the registration number UMIN 000026743 (the date of registration: March 28, 2017).

Effects of home-based exercise and branched-chain amino acid supplementation on aerobic capacity and glycemic control in patients with cirrhosis

AIM

The aim of the current study is to examine whether home-based step exercise at anaerobic threshold (AT) and branched-chain amino acid (BCAA) supplementation improve aerobic capacity, ectopic fat in liver and muscle, and glycemic control in patients with liver cirrhosis.

METHODS

Six female patients with compensated liver cirrhosis received oral BCAA and were instructed to undertake bench step exercises at an intensity that corresponded to AT, with a goal of performing 140 min of exercise per week at home for 12 months. Fat deposition in liver (liver to spleen ratio) and intramuscular adipose tissue content were assessed at baseline and after 6 and 12 months by computed tomography. Glycemic control indices (homeostasis model assessment of insulin resistance, hemoglobin A_1c [HbA_1c ], glycated albumin [GA] and chronic liver disease [CLD]-HbA_1c [average of HbA_1c and GA/3]) were also measured.

RESULTS

Twelve months of moderate training significantly increased AT, which is an index of aerobic capacity, but no changes were observed in body weight, liver to spleen ratio, or intramuscular adipose tissue content. Glycated albumin significantly decreased (P < 0.05) and there tended to be a similar decrease in CLD-HbA_1c (P < 0.1) after the exercise. The baseline serum triglyceride level correlated with changes in GA (P < 0.01) and CLD-HbA_1c (P < 0.1).

CONCLUSION

The current results suggest that the combination of home-based step exercise at AT and BCAA supplementation enhances aerobic capacity and potentially improves glycemic control in patients with cirrhosis without changes in body weight. The baseline serum serum triglyceride may partially explain the degree of improvement in glycemic control with exercise and BCAA intervention.

The effects of exercise on muscle strength, body composition, physical functioning and the inflammatory profile of older adults: a systematic review

PURPOSE OF REVIEW

This systematic review reports the most recent literature regarding the effects of physical exercise on muscle strength, body composition, physical functioning and inflammation in older adults. All articles were assessed for methodological quality and where possible effect size was calculated.

RECENT FINDINGS

Thirty-four articles were included - four involving frail, 24 healthy and five older adults with a specific disease. One reported on both frail and nonfrail patients. Several types of exercise were used: resistance training, aerobic training, combined resistance training and aerobic training and others. In frail older persons, moderate-to-large beneficial exercise effects were noted on inflammation, muscle strength and physical functioning. In healthy older persons, effects of resistance training (most frequently investigated) on inflammation or muscle strength can be influenced by the exercise modalities (intensity and rest interval between sets). Muscle strength seemed the most frequently used outcome measure, with moderate-to-large effects obtained regardless the exercise intervention studied. Similar effects were found in patients with specific diseases.

SUMMARY

Exercise has moderate-to-large effects on muscle strength, body composition, physical functioning and inflammation in older adults. Future studies should focus on the influence of specific exercise modalities and target the frail population more.

Cognitive Reserve and the Prevention of Dementia: the Role of Physical and Cognitive Activities

PURPOSE OF REVIEW

The article discusses the two most significant modifiable risk factors for dementia, namely, physical inactivity and lack of stimulating cognitive activity, and their effects on developing cognitive reserve.

RECENT FINDINGS

Both of these leisure-time activities were associated with significant reductions in the risk of dementia in longitudinal studies. In addition, physical activity, particularly aerobic exercise, is associated with less age-related gray and white matter loss and with less neurotoxic factors. On the other hand, cognitive training studies suggest that training for executive functions (e.g., working memory) improves prefrontal network efficiency, which provides support to brain functioning in the face of cognitive decline. While physical activity preserves neuronal structural integrity and brain volume (hardware), cognitive activity strengthens the functioning and plasticity of neural circuits (software), thus supporting cognitive reserve in different ways. Future research should examine whether lifestyle interventions incorporating these two domains can reduce incident dementia.