Marathon running increases circulating endothelial- and thrombocyte-derived microparticles

The association between marathon running and high-sensitivity cardiac troponin: A systematic review and meta-analysis

BACKGROUND

Marathon running is an extreme sport with a distance of about 42 kilometers. Its relationship to high-sensitivity cardiac troponin (hs-cTn) remains controversial.

OBJECTIVE

As the gold standard for detecting myocardial injury, the trends of hs-cTn before and after a marathon were investigated and analyzed.

METHODS

A literature search was conducted in PubMed, EMBASE, and Cochrane Library databases by combing the keywords marathon and troponin, and studies regarding high-sensitivity cardiac troponin I (hs-cTnI) and high-sensitivity cardiac troponin T (hs-cTnT) concentrations before and after marathon running (not for half-marathon and ultra-marathon) were included. "Quality Assessment Tool for Before-After (Pre-Post) Studies With No Control Group" were used to assess the risk of bias. Statistical analysis was performed using Review Manager, presenting data as mean values and 95% confidence intervals (CIs). Sensitivity analysis and subgroup analysis were performed if there was high heterogeneity among studies based on I2 statistic.

RESULTS

A total of 13 studies involving 824 marathoners were included in this systematic review and meta-analysis. Both hs-cTnI (MD 68.79 ng/L, [95% CI 53.22, 84.37], p< 0.001) and hs-cTnT (MD 42.91 ng/L, [95% CI 30.39, 55.43], p< 0.001) were elevated after running a marathon, but the concentration of hs-cTnT returned to baseline after 72 to 96 h post-race (MD 0.11 ng/L, [95% CI -1.30, 1.52], p= 0.88). The results of subgroup analysis demonstrated that the 99th percentile upper reference limit of hs-cTnT might be the source of heterogeneity.

CONCLUSION

The concentrations of hs-cTnI and hs-cTnT were increased after marathon running, but the change of hs-cTnT is usually not seen as irreversible myocardial injury.

Effects of Exercise on Circulating Extracellular Vesicles in Cardiovascular Disease

The evidence that physical exercise has multiple beneficial effects and is essential to a healthy lifestyle is widely accepted for a long-time. The functional and psychological changes promoted by exercise improve clinical outcomes and prognosis in several diseases, by decreasing mortality, disease severity, and hospital admissions. Nonetheless, the mechanisms that regulate the release, uptake, and communication of several factors in response to exercise are still not well defined. In the last years, extracellular vesicles have attracted significant interest in the scientific community due to their ability to carry and deliver proteins, lipids, and miRNA to distant organs in the body, promoting a very exciting crosstalk machinery. Moreover, increasing evidence suggests that exercise can modulate the release of those factors within EVs into the circulation, mediating its systemic adaptations.In this chapter, we summarize the effects of acute and chronic exercise on the extracellular vesicle dynamics in healthy subjects and patients with cardiovascular disease. The understanding of the changes in the cargo and kinetics of extracellular vesicles in response to exercise may open new possibilities of research and encourage the development of novel therapies that mimic the effects of exercise.

Circulating microparticles are associated with plaque burden and cause eNOS uncoupling in patients with carotid atherosclerosis

Aims: The study aimed to evaluate the correlation of different microparticle (MP) phenotypes with plaque burden and their diagnostic value and preliminarily explore the role of MPs in atherosclerosis (AS).

Methods: Carotid intima-media thickness (CIMT) and maximal plaque area in 23 patients with carotid atherosclerosis (CAS) and 22 healthy subjects were measured by ultrasound. Transmission electron microscopy, nanoparticle tracking analysis and western blot were used to identify MPs. Flow cytometry assay measured absolute number of MPs, and receiver operating characteristic (ROC) analysis was used to assess the relationship between plaque burden and MPs. To study the preliminary mechanism of MPs in AS, MPs were administered to 32 male Kunming mice, which were randomly divided into control, CAS, healthy, and tetrahydrobiopterin (BH4) groups. Hematoxylin-eosin staining, immunohistochemistry staining, and Western blot were adopted to detect relevant indexes 24 h after the injection.

Results: The plasma levels of CD45+ leukocyte-derived microparticle (LMP), CD11a+ LMP, CD11a+/CD45+ LMP, and CD31+/CD42b+ platelet-derived microparticle (PMP) in CAS patients were significantly higher than those in healthy subjects, and were positively correlated with the maximal plaque area. Moreover, the levels of CD11a+ LMP, CD11a+/CD45+ LMP were also positively correlated with CIMT. The area under the ROC curve of the four MPs was 0.689, 0.747, 0.741, and 0.701, respectively. Compared with healthy subjects, MPs from CAS patients resulted in a significantly lower expression of endothelial nitric oxide synthase (eNOS) dimer/monomer, and BH4 could improve eNOS uncoupling. Moreover, the level of VCAM-1 in intima in the CAS group was significantly higher than in the other three groups.

Conclusion: CD11a+ LMP and CD11a+/CD45+ LMP might be potential biomarkers for CAS prediction. BH4-related eNOS uncoupling occurs in CAS patients, and circulating MPs from them lead to endothelial dysfunction through eNOS uncoupling.

Extracellular Inflammasome Particles Are Released After Marathon Running and Induce Proinflammatory Effects in Endothelial Cells

Objectives: The intracellular NLRP3 inflammasome is an important regulator of sterile inflammation. Recent data suggest that inflammasome particles can be released into circulation. The effects of exercise on circulating extracellular apoptosis-associated speck-like protein (ASC) particles and their effects on endothelial cells are not known.

Methods: We established a flow cytometric method to quantitate extracellular ASC specks in human serum. ASC specks were quantitated in 52 marathon runners 24–72 h before, immediately after, and again 24–58 h after the run. For mechanistic characterization, NLRP3 inflammasome particles were isolated from a stable mutant NLRP3 (p.D303N)-YFP HEK cell line and used to treat primary human coronary artery endothelial cells.

Results: Athletes showed a significant increase in serum concentration of circulating ASC specks immediately after the marathon (+52% compared with the baseline, p < 0.05) and a decrease during the follow-up after 24–58 h (12% reduction compared with immediately after the run, p < 0.01). Confocal microscopy revealed that human endothelial cells can internalize extracellular NLRP3 inflammasome particles. After internalization, endothelial cells showed an inflammatory response with a higher expression of the cell adhesion molecule ICAM1 (6.9-fold, p < 0.05) and increased adhesion of monocytes (1.5-fold, p < 0.05).

Conclusion: These findings identify extracellular inflammasome particles as novel systemic mediators of cell–cell communication that are transiently increased after acute extensive exercise with a high mechanical muscular load.

Circulating extracellular vesicles delivering beneficial cargo as key players in exercise effects

Exercise has been recognized as an effective preventive and therapeutic approach for numerous diseases. This review addresses the potential role of circulating extracellular vesicles (EV) cargo that is modulated by physical activity. EV transport and deliver beneficial molecules to adjacent and distant tissues as a whole-body phenomenon, resulting in a healthier global status. Several candidate EV molecules, especially miRNAs, are summarized here as mediators of the beneficial effects of exercise, using different modalities, frequencies, volumes, and intensities. The following are among the candidate miRNAs: miR-21, miR-146, miR-486, miR-148a-3p, miR-223-3p, miR-142-3p, and miR-191a-5p. We highlight the relationship between EV cargo modifications, their targets and pathway interactions, in clinical outcomes, for example, on cardiovascular or immune diseases. This review brings an innovative perspective providing evidence for an intricate biological basis of the relationship between EV cargo and exercise-induced benefits on several diseases. Moreover, specific changes on circulating EV content might potentially be used as biomarkers of exercise efficacy.

Vascular Function Is Differentially Altered by Distance after Prolonged Running

PURPOSE

Ultraendurance exercise is steadily growing in popularity; however, the effect of increasingly prolonged durations of exercise on the vascular endothelium is unknown. The aim of this study was to characterize the effect of various ultramarathon running distances on vascular form and function.

METHODS

We evaluated vascular endothelial function via flow-mediated dilation (FMD) in the superficial femoral artery, as well as microvascular function, inflammatory factors, and central artery stiffness, before and after participants completed 25-km (7M:2F), 50-km (11M:10F), 80-km (9M:4F), or 160-km (9M:2F) trail races all run on the same day and course.

RESULTS

Completion required 149 ± 20, 386 ± 111, 704 ± 130, and 1470 ± 235 min, with corresponding average paces of 6.0 ± 0.8, 7.7 ± 2.2, 8.6 ± 1.3, and 9.6 ± 1.3 min·km-1, respectively. At baseline, there were no differences in participant characteristics across race distance groups. Shear rate stimulus trended toward an increase after the race (P = 0.07), but resting postrace artery diameter (P < 0.001) was elevated to a similar extent in all conditions. There was a reduction in FMD after the 50-km race (Δ -1.9% ± 2.2%, P < 0.01), but not the 25-km (Δ +0.3% ± 2.9%, P = 0.8), the 80-km (Δ -1.5% ± 3.2%, P = 0.1), or the 160-km (Δ +0.5% ± 2.5%, P = 0.5) race. Inflammatory markers increased most after 160 km, but arterial stiffness and microvascular function were not differently affected by race distance.

CONCLUSIONS

Although the superficial femoral artery baseline diameter was larger postexercise regardless of race distance, only the 50-km race reduced FMD, whereas a short-duration higher-intensity race (25 km) and longer-duration lower-intensity races (160 km) did not. Therefore, a 50-km ultramarathon may represent the intersection between higher-intensity exercise over a prolonged duration, causing reduced endothelial function not seen in shorter or longer distances.

Exercise and Circulating Microparticles in Healthy Subjects

This study aimed to explore the relationship between exercise and circulating microparticles (CMPs). PubMed, Web of Science, Embase, and the Cochrane Library databases were searched until August 13, 2020, using the terms "exercise" and "cell-derived microparticles." The Cochrane tool of risk of bias and the Methodological Index for Non-Randomized Studies were used to grade the studies. Twenty-six studies that met criteria were included in this review, including one before-after self-control study, 2 cohort studies, 4 randomized control trials, 5 case-control studies, and 14 descriptive studies. The studies were divided into a single bout and long-term exercise. The types of MPs contained endothelium-derived microparticles (EMPs), leukocyte-derived microparticles (LMPs), platelet-derived microparticles (PMPs), and erythrocyte-derived microparticles (ErMPs). This first systematic review found that the levels of CMPs continued to increase after a single bout of exercise in untrained subjects and were lower in trained subjects. PMPs expressed a transient increase after a single bout of exercise, and the proportion and duration of PMPs increment reduced in long-term exercise. Most studies showed a decline in LMPs in trained subjects after a single bout and long-term exercise, and variable changes were found in EMPs and ErMPs after exercise. A single bout of exercise drives the vessels exposed to high shear stress that promotes the formation of CMPs. However, the decline in CMPs in trained subjects may be attributed to the fact that they have a better ability to adapt to changes in hemodynamics and cellular function during exercise.

Circulating Extracellular Vesicles: The Missing Link between Physical Exercise and Depression Management?

Depression is associated with an increased risk of aging-related diseases. It is also seemingly a common psychological reaction to pandemic outbreaks with forced quarantines and lockdowns. Thus, depression represents, now more than ever, a major global health burden with therapeutic management challenges. Clinical data highlights that physical exercise is gaining momentum as a non-pharmacological intervention in depressive disorders. Although it may contribute to the reduction of systemic inflammation associated with depression, the mechanisms underlying the beneficial physical exercise effects in emotional behavior remain to be elucidated. Current investigations indicate that a rapid release of extracellular vesicles into the circulation might be the signaling mediators of systemic adaptations to physical exercise. These biological entities are now well-established intercellular communicators, playing a major role in relevant physiological and pathophysiological functions, including brain cell-cell communication. We also reviewed emerging evidence correlating depression with modified circulating extracellular vesicle surfaces and cargo signatures (e.g., microRNAs and proteins), envisioned as potential biomarkers for diagnosis, efficient disease stratification and appropriate therapeutic management. Accordingly, the clinical data summarized in the present review prompted us to hypothesize that physical exercise-related circulating extracellular vesicles contribute to its antidepressant effects, particularly through the modulation of inflammation. This review sheds light on the triad "physical exercise-extracellular vesicles-depression" and suggests new avenues in this novel emerging field.

Microvesicles in bronchoalveolar lavage as a potential biomarker of COPD

Microvesicles (MVs) released from almost all cells are recognized as cell communication tools. MVs have been investigated in several inflammatory diseases but poorly in biological fluids like bronchoalveolar lavage (BAL) of smokers. The purpose of this study was to investigate the presence and source of MVs in BAL of smokers with and without chronic obstructive pulmonary disease (COPD) compared with nonsmoking controls. Using flow cytometry in BAL, we detected endothelial and alveolar macrophage (AM)-derived MVs and found a higher number of AM-MVs in the BAL of smokers with COPD than in smokers without COPD and nonsmokers, which correlated with the pack-years (r = 0.46; P = 0.05) and with the degree of airway obstruction measured by the forced expiratory volume in 1 s percent predicted (r = -0.56; P = 0.01). Endothelial and alveolar macrophage-derived MVs are present and measurable in human BAL fluid. In response to smoking and to the development of COPD, inflammatory signals in AM-derived MVs can be quantified, and their numbers are related to the pack-years and the decrease in lung function. These results open the opportunity for future investigation of these microvesicles as biomarkers and possible mechanistic guides in COPD.

Effect of Physical Exercise on the Release of Microparticles with Angiogenic Potential

Cellular communication has a fundamental role in both human physiological and pathological states and various mechanisms are involved in the crosstalk between organs. Among these, microparticles (MPs) have an important involvement. MPs are a subtype of extracellular vesicles produced by a variety of cells following activation or apoptosis. They are normally present in physiological conditions, but their concentration varies in pathological states such as cardiovascular disease, diabetes mellitus, or cancer. Acute and chronic physical exercise are able to modify MPs amounts as well. Among various actions, exercise-responsive MPs affect angiogenesis, the process through which new blood vessels grow from pre-existing vessels. Usually, the neo vascular growth has functional role; but an aberrant neovascularization accompanies several oncogenic, ischemic, or inflammatory diseases. In addition, angiogenesis is one of the key adaptations to physical exercise and training. In the present review, we report evidence regarding the effect of various typologies of exercise on circulating MPs that are able to affect angiogenesis.

Extracellular vesicle species differentially affect endothelial cell functions and differentially respond to exercise training in patients with chronic coronary syndromes

BACKGROUND

Extracellular vesicles are released upon cellular activation and mediate inter-cellular communication. Individual species of extracellular vesicles might have divergent roles in vascular homeostasis and may show different responses to therapies such as exercise training.

AIMS

We examine endothelial effects of medium-size and small extracellular vesicles from the same individual with or without chronic coronary syndrome, and in chronic coronary syndrome patients participating in a four-week high-intensity interval training intervention.

METHODS

Human aortic endothelial cells were exposed to medium-size extracellular vesicles and small extracellular vesicles isolated from plasma samples of study participants. Endothelial cell survival, activation and re-endothelialisation capacity were assessed by respective staining protocols. Extracellular vesicles were quantified by nanoparticle tracking analysis and flow cytometry. Extracellular vesicle microRNA expression was quantified by realtime-quantitative polymerase chain reaction.

RESULTS

In patients with chronic coronary syndrome (n = 25), plasma counts of leukocyte-derived medium-size extracellular vesicles were higher than in age-matched healthy controls (n = 25; p = 0.04) and were reduced by high-intensity interval training (n = 15; p = 0.01 vs baseline). Re-endothelialisation capacity was promoted by medium-size extracellular vesicles from controls, but not by medium-size extracellular vesicles from chronic coronary syndrome patients. High-intensity interval training for 4 weeks enhanced medium-size extracellular vesicle-mediated support of in vitro re-endothelialisation. Small extracellular vesicles from controls or chronic coronary syndrome patients increased endothelial cell death and reduced repair functions and were not affected by high-intensity interval training.

CONCLUSION

The present study demonstrates that medium-size extracellular vesicles and small extracellular vesicles differentially affect endothelial cell survival and repair responses. This equilibrium is unbalanced in patients with chronic coronary syndrome where leukocyte-derived medium-size extracellular vesicles are increased leading to a loss of medium-size extracellular vesicle-mediated endothelial repair. High-intensity interval training partially restored medium-size extracellular vesicle-mediated endothelial repair, underlining its use in cardiovascular prevention and therapy to improve endothelial function.

Unraveling the steroid hormone response in male marathon runners: Correlation of running time with aldosterone and progesterone

Marathon running is a physical and psychological stressor. We aimed to characterize the response of nine steroid hormones, which include estradiol, progesterone, testosterone, cortisol, aldosterone, 17-hydroxyprogesterone, cortisone, androstenedione, and dehydroepiandrosterone sulfate, to marathon running and their association with performance. Blood samples of sixty men (age: 49.3 ± 5.9 years) who participated in the Berlin marathon were collected within 3 days before, within 30 min and within 58 h after the end of the marathon. The nine steroid hormones in serum were quantified using liquid chromatography-tandem mass spectrometry. The responses of nine steroid hormones to marathon running were characterized. Aldosterone (fold change: 8.5), progesterone (fold change: 6.6), and cortisol (fold change: 3.7) showed significant increases within 30 min after the marathon (all p < 0.0001). Estradiol but not testosterone increased in the male runners. Marathon running time was significantly related to aldosterone increase (beta=-0.238, p = 0.008) and progesterone increase (beta=-0.192, p = 0.036) in addition to body mass index, self-reported training distance, and age. Serum progesterone correlated with aldosterone and cortisol (r = 0.81 and r = 0.92, respectively, p < 0.001). Progesterone, as a precursor hormone, is increased after the completion of marathon running in association with the increase of aldosterone and cortisol. These findings reveal a contribution of progesterone during the response to the psycho-physical stress of marathon running in males.

Cardiac structure and function in response to a multi-stage marathon over 4486 km

Aims

To investigate whether participation in the Trans Europe Foot Race 2009 (TEFR), an ultramarathon race held over 64 consecutive days and 4486 km, led to changes in cardiac structure and function.

Methods

Cardiac magnetic resonance imaging was performed in 20 of 67 participating runners (two women; mean ± SD age 47.8 ± 10.4 years) at three time points (baseline scan at 294 ± 135 km (B), scan two at 1735 ± 86 km (T1) and scan three at 3370 ± 90 km (T2)) during the TEFR. Imaging included an assessment of left ventricular structure (mass) and function (strain). In parallel, cardiac troponin I, NT-pro-BNP, myostatin and GDF11 were determined in venous blood samples. A subsample of ten runners returned for a follow-up scan eight months after the race.

Results

Left ventricular mass increased significantly (B, 158.5 ± 23.8 g; T1, 165.1 ± 23.2 g; T2, 167 ± 24.6 g; p &lt; 0.001) over the course of the race, although no significant change was seen in the remaining structural and functional parameters. Serum concentrations of cardiac troponin I and NT-proBNP significantly increased 1.5 - and 3.5-fold, respectively, during the first measurement interval, with no further increase thereafter (cardiac troponin I, 6.8 ± 3.1 (B), 16.9 ± 10.4 (T1) and 17.1 ± 9.7 (T2); NT-proBNP, 30.3 ± 22.8 (B), 135.9 ± 177.5 (T1) and 111.2 ± 87.3 (T2)), whereas the growth markers myostatin and GDF11 did not change. No association was observed with functional parameters, including the ejection fraction and the volume of both ventricles. The follow-up scans showed a reduction to baseline values (left ventricular mass 157 ± 19.3 g).

Conclusions

High exercise-induced cardiac volume load for &gt;2 months in ultra-endurance runners results in a physiological structural adaptation with no sign of adverse cardiovascular remodelling.

The Influence of Compression Socks During a Marathon on Exercise-Associated Muscle Damage

CONTEXT

Compression socks have become increasingly popular with athletes due to perceived enhancement of exercise performance and recovery. However, research examining the efficacy of compression socks to reduce exercise-associated muscle damage has been equivocal, with few direct measurements of markers of muscle damage.

OBJECTIVE

To examine the influence of compression socks worn during a marathon on creatine kinase (CK) levels.

DESIGN

A randomized controlled trial.

SETTING

2013 Hartford Marathon, Hartford, CT.

PARTICIPANTS

Adults (n = 20) randomized to control (CONTROL; n = 10) or compression sock (SOCK; n = 10) groups.

MAIN OUTCOME MEASURES

Blood samples were collected 24 hours before, immediately after, and 24 hours following the marathon for the analysis of CK, a marker of muscle damage.

RESULTS

Baseline CK levels did not differ between CONTROL (89.3 [41.2] U/L) and SOCK (100.0 [56.2] U/L) (P = .63). Immediately following the marathon (≤1 h), CK increased 273% from baseline (P < .001 for time), with no difference in exercise-induced changes in CK from baseline between CONTROL (+293.9 [278.2] U/L) and SOCK (+233.1 [225.3] U/L; P = .60 for time × group). The day following the marathon (≤24 h), CK further increased 1094% from baseline (P < .001 for time), with no difference in changes in CK from baseline between CONTROL (+ 1191.9 [1194.8] U/L) and SOCK (+889.1 [760.2] U/L; P = .53 for time × group). These similar trends persisted despite controlling for potential covariates such as age, body mass index, and race finishing time (Ps > .29).

CONCLUSIONS

Compression socks worn during a marathon do not appear to mitigate objectively measured markers of muscle damage immediately following and 24 hours after a marathon.

Do the benefits of participation in sport and exercise outweigh the negatives? An academic review

Public health campaigns promote regular exercise and physical activity. These campaigns are founded on global recommendations that a combination of aerobic and resistance exercise is required, on a weekly basis, to maximise physical and mental health. However, participation in all forms of sports and physical activity has inherent risks that need to be considered by both health practitioners making activity recommendations and the people participating. This review examines biological, psychological and social benefits and harms of the three highest participation physical activities: walking/running, multidirectional sports and resistance exercise. While the remaining evidence indicates that the positives do outweigh the negatives, it demonstrates that moderate amounts of exercise provide the most optimal balance and that potential harms are typically associated with low or high participation.

Physical activity is associated with a large number of cardiovascular-specific proteins: Cross-sectional analyses in two independent cohorts

AIMS

We aimed to discover and replicate associations between leisure-time physical activity and cardiovascular candidate plasma protein biomarkers and to examine whether the associations were independent of body fat.

METHODS

We used cross-sectional data from two population-based cohorts, the EpiHealth (discovery cohort; n = 2239) and the Swedish Mammography Cohort - Clinical (SMCC; replication cohort; n = 4320). Physical activity during leisure time was assessed using questionnaires, and plasma concentrations of 184 proteins were assayed using the Olink Proseek Multiplex Cardiovascular 2 and 3 kits. We applied adjusted linear regression models using the False Discovery Rate to control for multiple testing in discovery.

RESULTS

In EpiHealth, physical activity was associated with 75 cardiovascular plasma biomarkers, of which 28 associations were verified (replicated) in SMCC. Findings include seven novel associations in human: paraoxonase 3, cystatin B, cathepsin Z, alpha-L-iduronidase, prostasin, growth differentiation factor 2 and tumour necrosis factor alpha receptor superfamily member 11A. Estimates for associations were similar across tertiles of body fat and physical activity was associated with four biomarkers independent of body fat percentage: paraoxonase 3, cystatin B, fatty acid-binding protein 4 and interleukin-1 receptor antagonist.

CONCLUSION

Leisure-time physical activity was associated with 28 cardiovascular-specific proteins; four associations were independent of body fat. Biomarkers in novel associations are involved in several atherosclerotic processes including regulation of low-density lipoprotein oxidation, protein degradation and immune cell adhesion and migration. Further research into these pathways may yield new insights into how physical activity affects cardiovascular health.

Differential effects of endurance, interval, and resistance training on telomerase activity and telomere length in a randomized, controlled study

Aims

It is unknown whether different training modalities exert differential cellular effects. Telomeres and telomere-associated proteins play a major role in cellular aging with implications for global health. This prospective training study examines the effects of endurance training, interval training (IT), and resistance training (RT) on telomerase activity and telomere length (TL).

Methods and results

One hundred and twenty-four healthy previously inactive individuals completed the 6 months study. Participants were randomized to three different interventions or the control condition (no change in lifestyle): aerobic endurance training (AET, continuous running), high-intensive IT (4 × 4 method), or RT (circle training on 8 devices), each intervention consisting of three 45 min training sessions per week. Maximum oxygen uptake (VO2max) was increased by all three training modalities. Telomerase activity in blood mononuclear cells was up-regulated by two- to three-fold in both endurance exercise groups (AET, IT), but not with RT. In parallel, lymphocyte, granulocyte, and leucocyte TL increased in the endurance-trained groups but not in the RT group. Magnet-activated cell sorting with telomerase repeat-ampliflication protocol (MACS-TRAP) assays revealed that a single bout of endurance training-but not RT-acutely increased telomerase activity in CD14+ and in CD34+ leucocytes.

Conclusion

This randomized controlled trial shows that endurance training, IT, and RT protocols induce specific cellular pathways in circulating leucocytes. Endurance training and IT, but not RT, increased telomerase activity and TL which are important for cellular senescence, regenerative capacity, and thus, healthy aging.

T Lymphocytes Contribute to the Control of Baseline Neural Precursor Cell Proliferation but Not the Exercise-Induced Up-Regulation of Adult Hippocampal Neurogenesis

Cross-talk between the peripheral immune system and the central nervous system is important for physiological brain health. T cells are required to maintain normal baseline levels of neural precursor proliferation in the hippocampus of adult mice. We show here that neither T cells, B cells, natural killer cells nor natural killer T cells are required for the increase in hippocampal precursor proliferation that occurs in response to physical exercise. In addition, we demonstrate that a subpopulation of T cells, regulatory T cells, is not involved in maintaining baseline levels of neural precursor proliferation. Even when applied at supraphysiological numbers, populations of both naive and stimulated lymphocytes had no effect on hippocampal precursor proliferation in vitro. In addition, physical activity had no effect on peripheral immune cells in terms of distribution in the bone marrow, lymph nodes or spleen, activation state or chemokine receptor (CXCR4 and CCR9) expression. Together these results suggest that lymphocytes are not involved in translating the peripheral effects of exercise to the neurogenic niche in the hippocampus and further support the idea that the exercise-induced regulation of adult neurogenesis is mechanistically distinct from its baseline control.

Exercise-Derived Microvesicles: A Review of the Literature

Initially suggested as simple cell debris, cell-derived microvesicles (MVs) have now gained acceptance as recognized players in cellular communication and physiology. Shed by most, and perhaps all, human cells, these tiny lipid-membrane vesicles carry bioactive agents, such as proteins, lipids and microRNA from their cell source, and are produced under orchestrated events in response to a myriad of stimuli. Physical exercise introduces systemic physiological challenges capable of acutely disrupting cell homeostasis and stimulating the release of MVs into the circulation. The novel and promising field of exercise-derived MVs is expanding quickly, and the following work provides a review of the influence of exercise on circulating MVs, considering both acute and chronic aspects of exercise and training. Potential effects of the MV response to exercise are highlighted and future directions suggested as exercise and sports sciences extend the realm of extracellular vesicles.

Towards frailty biomarkers: Candidates from genes and pathways regulated in aging and age-related diseases

OBJECTIVE

Use of the frailty index to measure an accumulation of deficits has been proven a valuable method for identifying elderly people at risk for increased vulnerability, disease, injury, and mortality. However, complementary molecular frailty biomarkers or ideally biomarker panels have not yet been identified. We conducted a systematic search to identify biomarker candidates for a frailty biomarker panel.

METHODS

Gene expression databases were searched (http://genomics.senescence.info/genes including GenAge, AnAge, LongevityMap, CellAge, DrugAge, Digital Aging Atlas) to identify genes regulated in aging, longevity, and age-related diseases with a focus on secreted factors or molecules detectable in body fluids as potential frailty biomarkers. Factors broadly expressed, related to several "hallmark of aging" pathways as well as used or predicted as biomarkers in other disease settings, particularly age-related pathologies, were identified. This set of biomarkers was further expanded according to the expertise and experience of the authors. In the next step, biomarkers were assigned to six "hallmark of aging" pathways, namely (1) inflammation, (2) mitochondria and apoptosis, (3) calcium homeostasis, (4) fibrosis, (5) NMJ (neuromuscular junction) and neurons, (6) cytoskeleton and hormones, or (7) other principles and an extensive literature search was performed for each candidate to explore their potential and priority as frailty biomarkers.

RESULTS

A total of 44 markers were evaluated in the seven categories listed above, and 19 were awarded a high priority score, 22 identified as medium priority and three were low priority. In each category high and medium priority markers were identified.

CONCLUSION

Biomarker panels for frailty would be of high value and better than single markers. Based on our search we would propose a core panel of frailty biomarkers consisting of (1) CXCL10 (C-X-C motif chemokine ligand 10), IL-6 (interleukin 6), CX3CL1 (C-X3-C motif chemokine ligand 1), (2) GDF15 (growth differentiation factor 15), FNDC5 (fibronectin type III domain containing 5), vimentin (VIM), (3) regucalcin (RGN/SMP30), calreticulin, (4) PLAU (plasminogen activator, urokinase), AGT (angiotensinogen), (5) BDNF (brain derived neurotrophic factor), progranulin (PGRN), (6) α-klotho (KL), FGF23 (fibroblast growth factor 23), FGF21, leptin (LEP), (7) miRNA (micro Ribonucleic acid) panel (to be further defined), AHCY (adenosylhomocysteinase) and KRT18 (keratin 18). An expanded panel would also include (1) pentraxin (PTX3), sVCAM/ICAM (soluble vascular cell adhesion molecule 1/Intercellular adhesion molecule 1), defensin α, (2) APP (amyloid beta precursor protein), LDH (lactate dehydrogenase), (3) S100B (S100 calcium binding protein B), (4) TGFβ (transforming growth factor beta), PAI-1 (plasminogen activator inhibitor 1), TGM2 (transglutaminase 2), (5) sRAGE (soluble receptor for advanced glycosylation end products), HMGB1 (high mobility group box 1), C3/C1Q (complement factor 3/1Q), ST2 (Interleukin 1 receptor like 1), agrin (AGRN), (6) IGF-1 (insulin-like growth factor 1), resistin (RETN), adiponectin (ADIPOQ), ghrelin (GHRL), growth hormone (GH), (7) microparticle panel (to be further defined), GpnmB (glycoprotein nonmetastatic melanoma protein B) and lactoferrin (LTF). We believe that these predicted panels need to be experimentally explored in animal models and frail cohorts in order to ascertain their diagnostic, prognostic and therapeutic potential.

Moderate-intensity exercise reduces activated and apoptotic endothelial microparticles in healthy midlife women

Endothelial microparticles (EMPs) are related to cardiovascular disease (CVD) risk. Risk factors for CVD increase with menopause, and greater cardiorespiratory fitness is generally expected to reduce CVD risk. The effects of habitual physical activity on endothelial health may be due in part to the effect of acute exercise on circulating EMPs. This study was performed to evaluate the effect of an acute bout of exercise on CD62E⁺ and CD31⁺/42b^- EMPs in healthy fit midlife women at different menopausal stages. Healthy, active premenopausal (PRE), perimenopausal (PERI), and postmenopausal (POST) women completed a single bout of moderate-intensity treadmill exercise. Activated (CD62E⁺) and apoptotic (CD31⁺/42b^-) EMPs were evaluated before and 30 min after exercise by using fluorescent activated cell sorting. In an exploratory analysis, these results were compared with data from low-fit peri- and postmenopausal women. Differences by group and time point were evaluated with repeated-measure ANOVAs. There was a reduction in the number of total microparticles ( P < 0.001), CD62E⁺ ( P = 0.003), and CD31⁺/42b^- ( P < 0.001) EMPs/μl plasma following acute exercise. The percentage of CD62E⁺ EMPs increased with acute exercise ( P < 0.001), whereas the percentage of CD31⁺/42b^- EMPs did not change ( P = 0.40). There was no effect of menopausal status on CD62E⁺or CD31⁺/42b^- EMPs, or on total microparticles (all P > 0.05). The exploratory analysis revealed that low-fit women had similar changes in EMPs with acute exercise. We concluded that acute moderate-intensity exercise reduces CD62E⁺and CD31⁺/42b^- EMPs, as well as total microparticles, in healthy midlife women. These effects occurred despite differences in menopausal status and fitness. NEW & NOTEWORTHY This study demonstrates that acute moderate-intensity exercise reduces activated and apoptotic endothelial microparticles in healthy midlife women.