Rapid upregulation and clearance of distinct circulating microRNAs after prolonged aerobic exercise

Non-coding RNAs in exercise immunology: A systematic review

Regular physical exercise has been recognized as a potent modulator of immune function, with its effects including enhanced immune surveillance, reduced inflammation, and improved overall health. While strong evidence exists that physical exercise affects the specific expression and activity of non-coding RNAs (ncRNAs) also involved in immune system regulation, heterogeneity in individual study designs and analyzed exercise protocols exists, and a condensed list of functional, exercise-dependent ncRNAs with known targets in the immune system is missing from the literature. A systematic review and qualitative analysis was used to identify and categorize ncRNAs participating in immune modulation by physical exercise. Two combined approaches were used: (a) a systematic literature search for "ncRNA and exercise immunology", (b) and a database search for microRNAs (miRNAs) (miRTarBase and DIANA-Tarbase v8) aligned with known target genes in the immune system based on the Reactome database, combined with a systematic literature search for "ncRNA and exercise". Literature searches were based on PubMed, Web of Science, and SPORTDiscus; and miRNA databases were filtered for targets validated by in vitro experimental data. Studies were eligible if they reported on exercise-based interventions in healthy humans. After duplicate removal, 95 studies were included reporting on 164 miRNAs, which were used for the qualitative synthesis. Six studies reporting on long-noncoding RNAs (lncRNAs) or circular RNAs were also identified. Results were analyzed using ordering tables that included exercise modality (endurance/resistance exercise), acute or chronic interventions, as well as the consistency in reported change between studies. Evaluation criteria were defined as "validated" with 100% of ≥3 independent studies showing identical direction of regulation, "plausible" (≥80%), or "suggestive" (≥70%). For resistance exercise, upregulation of miR-206 was validated while downregulation of miR-133a appeared plausible. For endurance exercise, 15 miRNAs were categorized as validated, with 12 miRNAs being consistently elevated and 3 miRNAs being downregulated, most of them after acute exercise training. In conclusion, our approach provides evidence that miRNAs play a major role in exercise-induced effects on the innate and adaptive immune system by targeting different pathways affecting immune cell distribution, function, and trafficking as well as production of (anti-)inflammatory cytokines. miRNAs miR-15, miR-29c, miR-30a, miR-142/3, miR-181a, and miR-338 emerged as key players in mediating the immunomodulatory effects of exercise predominantly after acute bouts of endurance exercise.

Global scientific trends in research of epigenetic response to exercise: A bibliometric analysis

The purpose of this work is to comprehensively understand the adaptive response of multiple epigenetic modifications on gene expression changes driven by exercise. Here, we retrieved literatures from publications in the PubMed and Web of Science Core Collection databases up to and including October 15, 2023. After screening with the exclusion criteria, 1910 publications were selected in total, comprising 1399 articles and 511 reviews. Specifically, a total of 512, 224, and 772 publications is involved in DNA methylation, histone modification, and noncoding RNAs, respectively. The correlations between publication number, authors, institutions, countries, references, and the characteristics of hotspots were explored by CiteSpace. Here, the USA (621 publications) ranked the world's most-influential countries, the University of California System (68 publications) was the most productive, and Tiago Fernandes (14 publications) had the most-published publications. A comprehensive keyword analysis revealed that cardiovascular disease, cancer, skeletal muscle development, and metabolic syndrome, and are the research hotspots. The detailed impact of exercise was further discussed in different aspects of these three categories of epigenetic modifications. Detailed analysis of epigenetic modifications in response to exercise, including DNA methylation, histone modification, and changes in noncoding RNAs, will offer valuable information to help researchers understand hotspots and emerging trends.

Left ventricle function and post-transcriptional events with exercise training in pigs

BACKGROUND

Standardized exercise protocols have been shown to improve overall cardiovascular fitness, but direct effects on left ventricular (LV) function, particularly diastolic function and relation to post-transcriptional molecular pathways (microRNAs (miRs)) are poorly understood. This project tested the central hypothesis that adaptive LV remodeling resulting from a large animal exercise training protocol, would be directly associated with specific miRs responsible for regulating pathways relevant to LV myocardial stiffness and geometry.

METHODS AND RESULTS

Pigs (n = 9; 25 Kg) underwent a 4 week exercise training protocol (10 degrees elevation, 2.5 mph, 10 min, 5 days/week) whereby LV chamber stiffness (KC) and regional myocardial stiffness (rKm) were measured by Doppler/speckle tracking echocardiography. Age and weight matched non-exercise pigs (n = 6) served as controls. LV KC fell by approximately 50% and rKm by 30% following exercise (both p < 0.05). Using an 84 miR array, 34 (40%) miRs changed with exercise, whereby 8 of the changed miRs (miR-19a, miR-22, miR-30e, miR-99a, miR-142, miR-144, miR-199a, and miR-497) were correlated to the change in KC (r ≥ 0.5 p < 0.05) and mapped to matrix and calcium handling processes. Additionally, miR-22 and miR-30e decreased with exercise and mapped to a localized inflammatory process, the inflammasome (NLRP-3, whereby a 2-fold decrease in NLRP-3 mRNA occurred with exercise (p < 0.05).

CONCLUSION

Chronic exercise reduced LV chamber and myocardial stiffness and was correlated to miRs that map to myocardial relaxation processes as well as local inflammatory pathways. These unique findings set the stage for utilization of myocardial miR profiling to identify underlying mechanisms by which exercise causes changes in LV myocardial structure and function.

Modulating Stress Susceptibility and Resilience: Insights from miRNA Manipulation and Neural Mechanisms in Mice

This study explored the impact of microRNAs, specifically mmu-miR-1a-3p and mmu-miR-155-5p, on stress susceptibility and resilience in mice of different strains. Previous research had established that C57BL/6J mice were stress-susceptible, while NET-KO and SWR/J mice displayed stress resilience. These strains also exhibited variations in the serum levels of mmu-miR-1a-3p and mmu-miR-155-5p. To investigate this further, we administered antagonistic sequences (Antagomirs) targeting these microRNAs to C57/BL/6J mice and their analogs (Agomirs) to NET-KO and SWR/J mice via intracerebroventricular (i.c.v) injection. The impact of this treatment was assessed using the forced swim test. The results showed that the stress-susceptible C57/BL/6J mice could be transformed into a stress-resilient phenotype through infusion of Antagomirs. Conversely, stress-resilient mice displayed altered behavior when treated with Ago-mmu-miR-1a-3p. The study also examined the expression of mmu-miR-1a-3p in various brain regions, revealing that changes in its expression in the cerebellum (CER) were associated with the stress response. In vitro experiments with the Neuro2a cell line indicated that the Antago/Ago-miR-1a-3p and Antago/Ago-miR-155-5p treatments affected mRNAs encoding genes related to cAMP and Ca2+ signaling, diacylglycerol kinases, and phosphodiesterases. The expression changes of genes such as Dgkq, Bdnf, Ntrk2, and Pde4b in the mouse cerebellum suggested a link between cerebellar function, synaptic plasticity, and the differential stress responses observed in susceptible and resilient mice. In summary, this research highlights the role of mmu-miR-1a-3p and mmu-miR-155-5p in regulating stress susceptibility and resilience in mice and suggests a connection between these microRNAs, cerebellar function, and synaptic plasticity in the context of stress response.

Long-Term Sports Practice and Atrial Fibrillation: An Updated Review of a Complex Relationship

Atrial fibrillation (AF) is the most common sustained arrhythmia in clinical practice, and it is an enormous burden worldwide because of its high morbidity, disability and mortality. It is generally acknowledged that physical activity (PA) is strongly associated with a significant reduction in the risk of cardiovascular (CV) disease and all-cause mortality. Moreover, it has been observed that moderate and regular physical activity has the potential to reduce the risk of AF, in addition to improving overall well-being. Nevertheless, some studies have associated intense physical activity with an increased risk of AF. This paper aims to review the main related literature to investigate the association between PA and AF incidence and draw pathophysiological and epidemiological conclusions.

How can we modulate aging through nutrition and physical exercise? An epigenetic approach

The World Health Organization predicts that by 2050, 2.1 billion people worldwide will be over 60 years old, a drastic increase from only 1 billion in 2019. Considering these numbers, strategies to ensure an extended "healthspan" or healthy longevity are urgently needed. The present study approaches the promotion of healthspan from an epigenetic perspective. Epigenetic phenomena are modifiable in response to an individual's environmental exposures, and therefore link an individual's environment to their gene expression pattern. Epigenetic studies demonstrate that aging is associated with decondensation of the chromatin, leading to an altered heterochromatin structure, which promotes the accumulation of errors. In this review, we describe how aging impacts epigenetics and how nutrition and physical exercise can positively impact the aging process, from an epigenetic point of view. Canonical histones are replaced by histone variants, concomitant with an increase in histone post-translational modifications. A slight increase in DNA methylation at promoters has been observed, which represses transcription of previously active genes, in parallel with global genome hypomethylation. Aging is also associated with deregulation of gene expression - usually provided by non-coding RNAs - leading to both the repression of previously transcribed genes and to the transcription of previously repressed genes. Age-associated epigenetic events are less common in individuals with a healthy lifestyle, including balanced nutrition, caloric restriction and physical exercise. Healthy aging is associated with more tightly condensed chromatin, fewer PTMs and greater regulation by ncRNAs.

A single session of EMS training induces long-lasting changes in circulating muscle but not cardiovascular miRNA levels: a randomized crossover study

Electromyostimulation (EMS) is used to maintain or build skeletal muscle and to increase cardiopulmonary fitness. Only limited data on the molecular mechanisms induced by EMS are available and effects on circulating microRNAs (c-miRNAs) have not been reported. This study aimed to evaluate whether EMS induces long-term changes in muscle- and cardiovascular-specific c-miRNA levels. Twelve healthy participants (33.0 ± 12.0 yr, 7 women) performed a 20-min whole body EMS training and a time- and intensity-matched whole body circuit training (CT) in random order. Blood samples were drawn pre-/posttraining and at 1.5, 3, 24, 48, and 72 h to determine creatine kinase (CK) and miRNA-21-5p, -126-3p, -133a-3p, -146a-5p, -206-3p, -222-3p, and -499a-5p levels. Muscular exertion was determined using an isometric strength test, and muscle soreness/pain was assessed by questionnaire. EMS participants reported higher muscle soreness 48 and 72 h postexercise and mean CK levels after EMS increased compared with CT at 48 and 72 h (time × group P ≤ 0.01). The EMS session induced a significant elevation of myomiR-206 and -133a levels starting at 1.5 and 3 h after exercise. Both miRNAs remained elevated for 72 h with significant differences between 24 and 72 h (time × group P ≤ 0.0254). EMS did not induce changes in cardiovascular miRNAs and no elevation in any miRNA was detected following CT. Time-course analysis of muscle damage marker CK and c-miR-133a and -206 levels did not suggest a common scheme (P ≥ 0.277). We conclude that a single EMS session induces specific long-lasting changes of miR-206 and miR-133 involved in muscle proliferation and differentiation. A single EMS session does not affect primary cardiovascular miRNA-21-5p, -126-3p, -146a-5p, and -222-3p levels.NEW & NOTEWORTHY Our study describes the long-term effects of electromyostimulation (EMS) on circulating miRNA levels. The observed increase of functional myomiR-206 and -133a levels over 72 h suggests long-lasting effects on muscle proliferation and differentiation, whereas cardiovascular miRNAs appear unaffected. Our findings suggest that circulating miRNAs provide useful insight into muscle regeneration processes after EMS and may thus be used to optimize EMS training effects.

Restoring Epigenetic Reprogramming with Diet and Exercise to Improve Health-Related Metabolic Diseases

Epigenetic reprogramming predicts the long-term functional health effects of health-related metabolic disease. This epigenetic reprogramming is activated by exogenous or endogenous insults, leading to altered healthy and different disease states. The epigenetic and environmental changes involve a roadmap of epigenetic networking, such as dietary components and exercise on epigenetic imprinting and restoring epigenome patterns laid down during embryonic development, which are paramount to establishing youthful cell type and health. Nutrition and exercise are among the most well-known environmental epigenetic factors influencing the proper developmental and functional lifestyle, with potential beneficial or detrimental effects on health status. The diet and exercise strategies applied from conception could represent an innovative epigenetic target for preventing and treating human diseases. Here, we describe the potential role of diet and exercise as therapeutic epigenetic strategies for health and diseases, highlighting putative future perspectives in this field.

The role of microRNAs in regulating inflammation and exercise-induced adaptations in rheumatoid arthritis

MicroRNAs (miRNAs) are endogenously generated single-stranded RNAs that play crucial roles in numerous biological processes, such as cell development, proliferation, differentiation, metabolism and apoptosis. They negatively regulate target gene expression by repressing translation of messenger RNA into a functional protein. Several miRNAs have been implicated in the development and progression of RA. They are involved in inflammatory and immune processes and are associated with susceptibility to RA and disease activity. They are also considered to be potential markers of disease activity or even therapeutic targets. Likewise, several miRNAs are affected acutely by exercise and regulate exercise-related adaptations in the skeletal muscle and cardiovascular system and aerobic fitness. Interestingly, some miRNAs affected by exercise are also important in the context of RA. Investigating these might increase our understanding of the effects of exercise in RA and improve exercise prescription and, potentially, disease management. In this review, we focus on the miRNAs that are associated with both RA and exercise and discuss their roles in (and potential interactions between) RA and exercise-induced adaptations.

Circulating microRNA levels after exercise-induced muscle damage and the repeated bout effect

The neuromuscular system can quickly adapt to exercise-induced muscle damage (EIMD), such that it is less affected by subsequent damaging exercise, a phenomenon known as the repeated bout effect (RBE). Circulating muscle-specific microRNAs (myomiRs) may be able to potentially predict the long-lasting maximal voluntary contraction (MVC) torque deficit (>24 h), an indicator of EIMD. We aimed to investigate: 1) how plasma myomiR levels are modified by the RBE and 2) whether plasma myomiRs can predict the long-lasting MVC torque deficit. Nineteen participants performed two identical bouts of loaded downhill walking separated by 2 wk. MVC torque, creatine kinase (CK) activity, myoglobin (Mb) concentration, and myomiR levels were measured before and up to 48 h after exercise. Correlation and multiple regression analyses were performed to assess the ability of these markers to predict the largest MVC torque loss beyond 24 h postexercise. Similar to MVC torque, CK activity, and the Mb concentration, the relative abundance of certain myomiRs (hsa-miR-1-3p, and hsa-miR-133a-3p) was less affected after the second bout of exercise relative to the first bout. The CK activity, Mb concentration, and level of several myomiRs (hsa-miR-1-3p, hsa-miR-133a-3p, and hsa-miR-206) correlated with long-lasting MVC torque loss. Multiple regression showed that the best combination of markers to predict the long-lasting deficit of MVC torque included several myomiRs, Mb, and CK. Certain myomiR levels increased less after exercise bout 2 than after exercise bout 1, indicating the presence of the RBE. The measurement of myomiR levels in combination with Mb concentrations and CK activity could improve the prediction of the long-lasting MVC torque deficit.NEW & NOTEWORTHY The present study is the first to show that plasma muscle-specific microRNA (myomiR) levels can be modified by the repeated bout effect, as their levels increased less after the second exercise bout relative to the first. This study is also the first to suggest that myomiR levels could be used to partially predict maximal voluntary contraction torque loss at 24 h postexercise (i.e., the magnitude of exercise-induced muscle damage). Interestingly, the combined measurement of certain myomiR levels with those of myoglobin and creatine kinase improved the predictive value.

MiRNA-based “fitness score” to assess the individual response to diet, metabolism, and exercise

Background

Regular, especially sustained exercise plays an important role in the prevention and treatment of multiple chronic diseases. Some of the underlying molecular and cellular mechanisms behind the adaptive response to physical activity are still unclear, but recent findings suggest a possible role of epigenetic mechanisms, especially miRNAs, in the progression and management of exercise-related changes. Due to the combination of the analysis of epigenetic biomarkers (miRNAs), the intake of food and supplements, and genetic dispositions, a “fitness score” was evaluated to assess the individual response to nutrition, exercise, and metabolic influence.

Methods

In response to a 12-week sports intervention, we analyzed genetic and epigenetic biomarkers in capillary blood from 61 sedentary, healthy participants (66.1% females, 33.9% males, mean age 33 years), including Line-1 methylation, three SNPs, and ten miRNAs using HRM and qPCR analysis. These biomarkers were also analyzed in a healthy, age- and sex-matched control group (n, 20) without intervention. Food frequency intake, including dietary supplement intake, and general health questionnaires were surveyed under the supervision of trained staff.

Results

Exercise training decreased the expression of miR-20a-5p, −22-5p, and −505-3p (p < 0.02) and improved the “fitness score,” which estimates eight different lifestyle factors to assess, nutrition, inflammation, cardiovascular fitness, injury risk, regeneration, muscle and hydration status, as well as stress level. In addition, we were able to determine correlations between individual miRNAs, miR-20a-5p, −22-5p, and −101-3p (p < 0.04), and the genetic predisposition for endurance and/or strength and obesity risk (ACE, ACTN3, and FTO), as well as between miRNAs and the body composition (p < 0.05). MiR-19b-3p and −101-3p correlated with the intake of B vitamins. Further, miR-19b-3p correlated with magnesium and miR-378a-3p with iron intake (p < 0.05).

Conclusions

In summary, our results indicate that a combined analysis of several biomarkers (miRNAs) can provide information about an individual’s training adaptions/fitness, body composition, nutritional needs, and possible recovery. In contrast to most studies using muscle biopsies, we were able to show that these biomarkers can also be measured using a minimally invasive method.

Epigenetics in the primary and secondary prevention of cardiovascular disease: influence of exercise and nutrition

Increasing evidence links changes in epigenetic systems, such as DNA methylation, histone modification, and non-coding RNA expression, to the occurrence of cardiovascular disease (CVD). These epigenetic modifications can change genetic function under influence of exogenous stimuli and can be transferred to next generations, providing a potential mechanism for inheritance of behavioural intervention effects. The benefits of exercise and nutritional interventions in the primary and secondary prevention of CVD are well established, but the mechanisms are not completely understood. In this review, we describe the acute and chronic epigenetic effects of physical activity and dietary changes. We propose exercise and nutrition as potential triggers of epigenetic signals, promoting the reshaping of transcriptional programmes with effects on CVD phenotypes. Finally, we highlight recent developments in epigenetic therapeutics with implications for primary and secondary CVD prevention.

Roles of physical exercise-induced MiR-126 in cardiovascular health of type 2 diabetes

Although physical activity is widely recommended for preventing and treating cardiovascular complications of type 2 diabetes mellitus (T2DM), the underlying mechanisms remain unknown. MicroRNA-126 (miR-126) is an angiogenetic regulator abundant in endothelial cells (ECs) and endothelial progenitor cells (EPCs). It is primarily involved in angiogenesis, inflammation and apoptosis for cardiovascular protection. According to recent studies, the levels of miR-126 in the myocardium and circulation are affected by exercise protocol. High-intensity interval training (HIIT) or moderate-and high-intensity aerobic exercise, whether acute or chronic, can increase circulating miR-126 in healthy adults. Chronic aerobic exercise can effectively rescue the reduction of myocardial and circulating miR-126 and vascular endothelial growth factor (VEGF) in diabetic mice against diabetic vascular injury. Resistance exercise can raise circulating VEGF levels, but it may have a little influence on circulating miR-126. The Several targets of miR-126 have been suggested for cardiovascular fitness, such as sprouty-related EVH1 domain-containing protein 1 (SPRED1), phosphoinositide-3-kinase regulatory subunit 2 (PIK3R2), vascular cell adhesion molecule 1 (VCAM1), high-mobility group box 1 (HMGB1), and tumor necrosis factor receptor-associated factor 7 (TRAF7). Here, we present a comprehensive review of the roles of miR-126 and its downstream proteins as exercise mechanisms, and propose that miR-126 can be applied as an exercise indicator for cardiovascular prescriptions and as a preventive or therapeutic target for cardiovascular complications in T2DM.

Effects of Native Whey Protein and Carbohydrate Supplement on Physical Performance and Plasma Markers of Muscle Damage and Inflammation during a Simulated Rugby Sevens Tournament: A Double-Blind, Randomized, Placebo-Controlled, Crossover Study

The importance of optimized recovery during a sport competition is undisputed. The objective of this study was to determine the effects of recovery drinks comprising either carbohydrate only, or a mix of native whey proteins and carbohydrate to maintain physical performance and minimize muscle damage during a simulated rugby sevens (rugby 7s) tournament. Twelve well-trained male rugby players participated in three simulated rugby 7s tournament days with a week's interval in between. Each tournament comprised a sequence of three simulated matches, interspersed with 2 h of recovery. Three different recovery drinks were tested: a placebo (PLA, nonenergetic chocolate-flavored drink), a carbohydrate drink (CHO, 80 g of carbohydrate) or an isoenergetic carbohydrate-protein drink (P-CHO, 20 g of Pronativ^®, native whey protein and 60 g of carbohydrate). A different recovery drink, consumed after each match, was tested during each simulated tournament. Physical performance, muscle damage and muscle pain were assessed before and after each simulated tournament. Regarding physical performance, both P-CHO and CHO drinks had a positive effect on the maintenance of 50 m sprint time compared to the PLA drink (effect sizes large and moderate, respectively). Regarding muscle damage, the P-CHO supplement attenuated the creatine phosphokinase increase at POST6 compared to PLA (effect size, moderate). Finally, P-CHO and CHO drinks reduced the exercise-induced DOMS (effect size, moderate), compared to the PLA condition (effect size, large), while P-CHO only reduced pain on muscle palpation and pain when descending stairs compared to PLA 24 h post-tournament (effect size, small). This study suggests that consuming a recovery drink containing native whey proteins and carbohydrate or carbohydrate only after each match of a rugby 7s tournament may attenuate the exercise-induced increase in markers of muscle damage and maintain physical performance.

A Miniaturized MicroRNA Sensor Identifies Targets Associated with Weight Loss in a Diet and Exercise Intervention among Healthy Overweight Individuals

Weight loss through dietary and exercise intervention is commonly prescribed but is not effective for all individuals. Recent studies have demonstrated that circulating microRNA (miR) biomarkers could potentially be used to identify individuals who will likely lose weight through diet and exercise and attain a healthy body weight. However, accurate detection of miRs in clinical samples is difficult, error-prone, and expensive. To address this issue, we recently developed iLluminate-a low-cost and highly sensitive miR sensor suitable for point-of-care testing. To investigate if miR testing and iLluminate can be used in real-world obesity applications, we developed a pilot diet and exercise intervention and utilized iLluminate to evaluate miR biomarkers. We evaluated the expression of miRs-140, -935, -let-7b, and -99a, which are biomarkers for fat loss, energy metabolism, and adipogenic differentiation. Responders lost more total mass, tissue mass, and fat mass than non-responders. miRs-140, -935, -let-7b, and -99a, collectively accounted for 6.9% and 8.8% of the explained variability in fat and lean mass, respectively. At the level of the individual coefficients, miRs-140 and -935 were significantly associated with fat loss. Collectively, miRs-140 and -935 provide an additional degree of predictive capability in body mass and fat mass alternations.

Systematic assessment of microRNAs associated with lung cancer and physical exercise

It has long been evident that physical exercise reduces the risk of cancer and improves treatment efficacy in tumor patients, particularly in lung cancer (LC). Several molecular mechanisms have been reported, but the mechanisms related to microRNAs (miRNAs) are not well understood. MiRNAs modulated various basic biological processes by negatively regulating gene expression and can be transmitted between cells as signaling molecules. Recent studies have shown that miRNAs are actively released into the circulation during exercise, and are deeply involved in cancer pathology. Hence, the role of exercise intervention in LC treatment may be further understood by identifying miRNAs associated with LC and physical activity. Here, miRNAs expression datasets related to LC and exercise were collected to screen altered miRNAs. Further bioinformatic approaches were performed to analyze the value of the selected miRNAs. The results identified 42 marker miRNAs in LC, of which three core-miRNAs (has-miR-195, has-miR-26b, and has-miR-126) were co-regulated by exercise and cancer, mainly involved in cell cycle and immunity. Our study supports the idea that using exercise intervention as adjuvant therapy for LC patients. These core-miRNAs, which are down-regulated in cancer but elevated by exercise, may act as suppressors in LC and serve as non-invasive biomarkers for cancer prevention.

Using ncRNAs as Tools in Cancer Diagnosis and Treatment-The Way towards Personalized Medicine to Improve Patients' Health

Although the first discovery of a non-coding RNA (ncRNA) dates back to 1958, only in recent years has the complexity of the transcriptome started to be elucidated. However, its components are still under investigation and their identification is one of the challenges that scientists are presently facing. In addition, their function is still far from being fully understood. The non-coding portion of the genome is indeed the largest, both quantitatively and qualitatively. A large fraction of these ncRNAs have a regulatory role either in coding mRNAs or in other ncRNAs, creating an intracellular network of crossed interactions (competing endogenous RNA networks, or ceRNET) that fine-tune the gene expression in both health and disease. The alteration of the equilibrium among such interactions can be enough to cause a transition from health to disease, but the opposite is equally true, leading to the possibility of intervening based on these mechanisms to cure human conditions. In this review, we summarize the present knowledge on these mechanisms, illustrating how they can be used for disease treatment, the current challenges and pitfalls, and the roles of environmental and lifestyle-related contributing factors, in addition to the ethical, legal, and social issues arising from their (improper) use.

Epigenetic Alterations in Sports-Related Injuries

It is a well-known fact that physical activity benefits people of all age groups. However, highly intensive training, maladaptation, improper equipment, and lack of sufficient rest lead to contusions and sports-related injuries. From the perspectives of sports professionals and those performing regular–amateur sports activities, it is important to maintain proper levels of training, without encountering frequent injuries. The bodily responses to physical stress and intensive physical activity are detected on many levels. Epigenetic modifications, including DNA methylation, histone protein methylation, acetylation, and miRNA expression occur in response to environmental changes and play fundamental roles in the regulation of cellular activities. In the current review, we summarise the available knowledge on epigenetic alterations present in tissues and organs (e.g., muscles, the brain, tendons, and bones) as a consequence of sports-related injuries. Epigenetic mechanism observations have the potential to become useful tools in sports medicine, as predictors of approaching pathophysiological alterations and injury biomarkers that have already taken place.

Longitudinal assessment of blood-borne musculoskeletal disease biomarkers in the DE50-MD dog model of Duchenne muscular dystrophy

Background: Duchenne muscular dystrophy (DMD) is a fatal muscle wasting disease caused by mutations in the dystrophin gene. Due to their phenotypic similarity to human patients, large animal models are invaluable tools for pre-clinical trials. The DE50-MD dog is a relatively new model of DMD, and carries a therapeutically-tractable mutation lying within the hotspot for human patients, making it especially valuable. Prior to conducting therapeutic trials using this novel animal model, it is essential to establish a panel of viable biomarkers. Methods: We evaluated a panel of blood-borne biomarkers of musculoskeletal disease in the DE50-MD dog. Venous blood samples were obtained monthly throughout an 18-month study period in DE50-MD (N=18) and wild-type (WT) control (N=14) dogs. A panel of potential plasma/serum biomarkers of DMD was measured and their theoretical utility in future clinical trials determined using sample size calculations. Results: Compared to WT dogs, DE50-MD dogs had substantially higher circulating creatine kinase (CK) activities, myomesin-3 (MYOM3), and the dystromiRs miR-1, miR-133a and miR-206, but significantly lower serum myostatin concentrations. An age-associated pattern, similar to that observed in DMD patients, was seen for CK and MYOM3. Sample size calculations suggested that low cohort sizes (N≤3) could be used to detect up to a 50% improvement in DE50-MD results towards WT levels for each biomarker or a combination thereof (via principal component analysis); as few as N=3 animals should enable detection of a 25% improvement using a combined biomarker approach (alpha 0.05, power 0.8). Conclusions: We have established a panel of blood-borne biomarkers that could be used to monitor musculoskeletal disease or response to a therapeutic intervention in the DE50-MD dog using low numbers of animals. The blood biomarker profile closely mimics that of DMD patients, supporting the hypothesis that this DMD model would be suitable for use in pre-clinical trials.

Longitudinal assessment of blood-borne musculoskeletal disease biomarkers in the DE50-MD dog model of Duchenne muscular dystrophy

Background: Duchenne muscular dystrophy (DMD) is a fatal muscle wasting disease caused by mutations in the dystrophin gene. Due to their phenotypic similarity to human patients, large animal models are invaluable tools for pre-clinical trials. The DE50-MD dog is a relatively new model of DMD, and carries a therapeutically-tractable mutation lying within the hotspot for human patients, making it especially valuable. Prior to conducting therapeutic trials using this novel animal model, it is essential to establish a panel of viable biomarkers. Methods: We evaluated a panel of blood-borne biomarkers of musculoskeletal disease in the DE50-MD dog. Venous blood samples were obtained monthly throughout an 18-month study period in DE50-MD (N=18) and wild-type (WT) control (N=14) dogs. A panel of potential plasma/serum biomarkers of DMD was measured and their theoretical utility in future clinical trials determined using sample size calculations. Results: Compared to WT dogs, DE50-MD dogs had substantially higher circulating creatine kinase (CK) activities, myomesin-3 (MYOM3), and the dystromiRs miR-1, miR-133a and miR-206, but significantly lower serum myostatin concentrations. An age-associated pattern, similar to that observed in DMD patients, was seen for CK and MYOM3. Sample size calculations suggested that low cohort sizes (N≤3) could be used to detect up to a 50% improvement in DE50-MD results towards WT levels for each biomarker or a combination thereof (via principal component analysis); as few as N=3 animals should enable detection of a 25% improvement using a combined biomarker approach (alpha 0.05, power 0.8). Conclusions: We have established a panel of blood-borne biomarkers that could be used to monitor musculoskeletal disease or response to a therapeutic intervention in the DE50-MD dog using low numbers of animals. The blood biomarker profile closely mimics that of DMD patients, supporting the hypothesis that this DMD model would be suitable for use in pre-clinical trials.

miR-133a-A Potential Target for Improving Cardiac Mitochondrial Health and Regeneration After Injury

ABSTRACT

The various roles of muscle secretory factors and myokines have been well studied, but in recent decades, the role of myocyte-specific microRNAs (myomiRs) has gained momentum. These myomiRs are known to play regulatory roles in muscle health in general, both skeletal muscle and cardiac muscle. In this review, we have focused on the significance of a myomiR termed miR-133a in cardiovascular health. The available literature supports the claim that miR-133a could be helpful in the healing process of muscle tissue after injury. The protective function could be due to its regulatory effect on muscle or stem cell mitochondrial function. In this review, we have shed light on the protective mechanisms offered by miR-133a. Most of the beneficial effects are due to the presence of miR-133a in circulation or tissue-specific expression. We have also reviewed the potential mechanisms by which miR-133a could interact with cell surface receptors and also transcriptional mechanisms by which they offer cardioprotection and regeneration. Understanding these mechanisms will help in finding an ideal strategy to repair cardiac tissue after injury.

MicroRNAs as biomarkers for monitoring cardiovascular changes in Type II Diabetes Mellitus (T2DM) and exercise

Introduction

MicroRNAs (miRNAs) have been shown to be altered in both CVD and T2DM and can have an application as diagnostic and prognostic biomarkers. miRNAs are released into circulation when the cardiomyocyte is subjected to injury and damage.

Objectives

Measuring circulating miRNA levels in human plasma may be of great potential use for measuring the extent of damage to cardiomyocytes and response to exercise. This review is aimed to highlight the potential application of miRNAs as biomarkers of CVD progression in T2DM, and the impact of exercise on recovery.

Methods

The review aims to examine whether the health improvements following exercise in T2DM patients are reflective of changes in expression of plasma miRNAs. For this purpose, studies were identified from the literature that have established a correlation between diabetes, disease progression and plasma miRNA levels. We also reviewed studies which looked at the effect of exercise on plasma miRNA levels.

Results

The review identified miRNA signatures that are affected by T2DM and DHD and a subset of these miRNAs that are also affected by different types of exercise. This approach helped us to identify those miRNAs whose expression and function can be altered by regular bouts of exercise.

Conclusions

miRNAs identified as part of this review can serve as tools to monitor the cardio-protective, anti-inflammatory and metabolic effects of exercise in people suffering from T2DM. Future research should focus on regulation of these miRNAs in T2DM and how they can be altered by appropriate exercise interventions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-022-01066-4.

Long-Term Strenuous Exercise Promotes Vascular Injury by Selectively Damaging the Tunica Media

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Long-term strenuous endurance training promotes a deleterious vascular remodeling, in contrast to the beneficial effects of moderate exercise.

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Tunica media fibrosis, possibly mediated by miR-212, miR-132, and miR-146b down-regulation, and intrinsic vascular smooth muscle cell stiffening may contribute to aortic stiffening.

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Endothelial function improves in a similar intensity after moderate and strenuous training. However, in the INT group, a larger NO-mediated vasorelaxation is compensated by more intense vasoconstriction, leading to a potentially unstable balance.

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Strenuous exercise-induced vascular stiffening and changes in endothelial function remain after ceasing physical activity.

Moderate exercise has well-founded benefits in cardiovascular health. However, increasing, yet controversial, evidence suggests that extremely trained athletes may not be protected from cardiovascular events as much as moderately trained individuals. In our rodent model, intensive but not moderate training promoted aorta and carotid stiffening and elastic lamina ruptures, tunica media thickening of intramyocardial arteries, and an imbalance between vasoconstrictor and relaxation agents. An up-regulation of angiotensin-converter enzyme, miR-212, miR-132, and miR-146b might account for this deleterious remodeling. Most changes remained after a 4-week detraining. In conclusion, our results suggest that intensive training blunts the benefits of moderate exercise.

Exercise-Induced Circulating microRNAs: Potential Key Factors in the Control of Breast Cancer

Losses in skeletal muscle mass, strength, and metabolic function are harmful in the pathophysiology of serious diseases, including breast cancer. Physical exercise training is an effective non-pharmacological strategy to improve health and quality of life in patients with breast cancer, mainly through positive effects on skeletal muscle mass, strength, and metabolic function. Emerging evidence has also highlighted the potential of exercise-induced crosstalk between skeletal muscle and cancer cells as one of the mechanisms controlling breast cancer progression. This intercellular communication seems to be mediated by a group of skeletal muscle molecules released in the bloodstream known as myokines. Among the myokines, exercise-induced circulating microRNAs (c-miRNAs) are deemed to mediate the antitumoral effects produced by exercise training through the control of key cellular processes, such as proliferation, metabolism, and signal transduction. However, there are still many open questions regarding the molecular basis of the exercise-induced effects on c-miRNA on human breast cancer cells. Here, we present evidence regarding the effect of exercise training on c-miRNA expression in breast cancer, along with the current gaps in the literature and future perspectives.

State of Knowledge on Molecular Adaptations to Exercise in Humans: Historical Perspectives and Future Directions

For centuries, regular exercise has been acknowledged as a potent stimulus to promote, maintain, and restore healthy functioning of nearly every physiological system of the human body. With advancing understanding of the complexity of human physiology, continually evolving methodological possibilities, and an increasingly dire public health situation, the study of exercise as a preventative or therapeutic treatment has never been more interdisciplinary, or more impactful. During the early stages of the NIH Common Fund Molecular Transducers of Physical Activity Consortium (MoTrPAC) Initiative, the field is well-positioned to build substantially upon the existing understanding of the mechanisms underlying benefits associated with exercise. Thus, we present a comprehensive body of the knowledge detailing the current literature basis surrounding the molecular adaptations to exercise in humans to provide a view of the state of the field at this critical juncture, as well as a resource for scientists bringing external expertise to the field of exercise physiology. In reviewing current literature related to molecular and cellular processes underlying exercise-induced benefits and adaptations, we also draw attention to existing knowledge gaps warranting continued research effort. © 2021 American Physiological Society. Compr Physiol 12:3193-3279, 2022.

Regulation of microRNAs in Alzheimer´s disease, type 2 diabetes, and aerobic exercise training

Alzheimer's disease (AD) is the most common type of dementia. The evolution and aggregation of amyloid beta (β) oligomers is linked to insulin resistance in AD, which is also the major characteristic of type 2 diabetes (T2D). Being physically inactive can contribute to the development of AD and/or T2D. Aerobic exercise training (AET), a type of physical exercise, can be useful in preventing or treating the negative outcomes of AD and T2D. AD, T2D and AET can regulate the expression of microRNAs (miRNAs). Here, we review some of the changes in miRNAs expression regulated by AET, AD and T2D. MiRNAs play an important role in the gene regulation of key signaling pathways in both pathologies, AD and T2D. MiRNA dysregulation is evident in AD and has been associated with several neuropathological alterations, such as the development of a reactive gliosis. Expression of miRNAs are associated with many pathophysiological mechanisms involved in T2D like insulin synthesis, insulin resistance, glucose intolerance, hyperglycemia, intracellular signaling, and lipid profile. AET regulates miRNAs levels. We identified 5 miRNAs (miR-21, miR-29a/b, miR-103, miR-107, and miR-195) that regulate gene expression and are modulated by AET on AD and T2D. The identified miRNAs are potential targets to treat the symptoms of AD and T2D. Thus, AET is a non-pharmacological tool that can be used to prevent and fight the negative outcomes in AD and T2D.

Associations between circulating microRNAs and coronary plaque characteristics: potential impact from physical exercise

Background and aims MicroRNAs (miRs) are involved in different steps in the development of atherosclerosis and are proposed as promising biomarkers of coronary artery disease (CAD). We hypothesized that circulating levels of miRs were associated with coronary plaque components assessed by radiofrequency intravascular ultrasound (RF-IVUS) before and after aerobic exercise intervention. Methods 31 patients with CAD treated with percutaneous coronary intervention (PCI) previously included in a randomized trial with aerobic interval training (AIT) or moderate continuous training (MCT) as post-PCI intervention were included. Coronary plaque characteristics by grayscale and RF-IVUS and predefined circulating candidate miRs in plasma were analysed at baseline and follow-up. Associations between miRs and coronary plaque composition, and the potential effect from exercise, were analysed using linear regression. Results Circulating levels of miR-15a-5p, miR-30e-5p, miR-92a-3p, miR-199a-3p, miR-221-3p, and miR-222-3p were associated with baseline coronary necrotic core volume. Following exercise intervention, decreased levels of miR-15a-5p, miR-93-5p, and miR-451a, and increased levels of miR-146a-5p were associated with an observed regression of coronary plaque burden. A mirPath prediction tool identified that genes regulated by miR-15a-5p, miR-199a-3p, and miR-30e-5p were significantly overrepresented in pathways related to fatty acid biosynthesis and fatty acid metabolism. Conclusion This exploratory study demonstrated six miRs associated with coronary necrotic core, a marker of plaque vulnerability. In addition, changes in four miRs were associated with a regression of coronary plaque burden following exercise intervention. These novel findings may identify potential future biomarkers of CAD and coronary plaque composition.

Changes in circulating microRNAs following head impacts in soccer

AIM

To explore the short-term effects of accidental head impacts and repetitive headers on circulating microRNAs, accounting for the effects of high-intensity exercise alone.

METHODS

Blood samples were collected from professional soccer players at rest. Repeat samples were drawn 1 h and 12 h after three conditions: (1) accidental head impacts in a match, (2) repetitive headers during training, and (3) high-intensity exercise. 89 samples were screened to detect microRNAs expressed after each exposure. Identified microRNAs were then validated in 98 samples to determine consistently deregulated microRNAs. Deregulated microRNAs were further explored using bioinformatics to identify target genes and characterize their involvement in biological pathways.

RESULTS

Accidental head impacts led to deregulation of eight microRNAs that were unaffected by high-intensity exercise; target genes were linked to 12 specific signaling pathways, primarily regulating chromatin organization, Hedgehog and Wnt signaling. Repetitive headers led to deregulation of six microRNAs that were unaffected by high-intensity exercise; target genes were linked to one specific signaling pathway (TGF-β). High-intensity exercise led to deregulation of seven microRNAs; target genes were linked to 31 specific signaling pathways.

CONCLUSION

We identified microRNAs specific to accidental head impacts and repetitive headers in soccer, potentially being useful as brain injury biomarkers.

MicroRNAs in obesity, sarcopenia, and commonalities for sarcopenic obesity: a systematic review

Sarcopenic obesity is a distinct condition of sarcopenia in the context of obesity, with the cumulative health risks of both phenotypes. Differential expression of microRNAs (miRNAs) has been reported separately in people with obesity and sarcopenia and may play a role in the pathogenesis of sarcopenic obesity. However, this has not been explored to date. This study aimed to identify differentially expressed miRNAs reported in serum, plasma, and skeletal muscle of people with obesity and sarcopenia and whether there are any commonalities between these conditions. We performed a systematic review on Embase and MEDLINE (PROSPERO, CRD42020224486) for differentially expressed miRNAs (fold change >1.5 or P-value <0.05) in (i) sarcopenia or frailty and (ii) obesity or metabolic syndrome. The functions and targets of miRNAs commonly changed in both conditions, in the same direction, were searched using PubMed. Following deduplication, 247 obesity and 42 sarcopenia studies were identified for full-text screening. Screening identified 36 obesity and 6 sarcopenia studies for final inclusion. A total of 351 miRNAs were identified in obesity and 157 in sarcopenia. Fifty-five miRNAs were identified in both obesity and sarcopenia-by sample type, 48 were found in plasma and one each in serum and skeletal muscle. Twenty-four miRNAs were identified from 10 of the included studies as commonly changed in the same direction (22 in plasma and one each in serum and skeletal muscle) in obesity and sarcopenia. The majority of miRNA-validated targets identified in the literature search were members of the phosphoinositide 3-kinase/protein kinase B and transforming growth factor-β signalling pathways. The most common targets identified were insulin-like growth factor 1 (miR-424-5p, miR-483-3p, and miR-18b-5p) and members of the SMAD family (miR-483-3p, miR-92a-3p, and miR-424-5p). The majority of commonly changed miRNAs were involved in protein homeostasis, mitochondrial dynamics, determination of muscle fibre type, insulin resistance, and adipogenesis. Twenty-four miRNAs were identified as commonly dysregulated in obesity and sarcopenia with functions and targets implicated in the pathogenesis of sarcopenic obesity. Given the adverse health outcomes associated with sarcopenic obesity, understanding the pathogenesis underlying this phenotype has the potential to lead to effective screening, monitoring, or treatment strategies. Further research is now required to confirm whether these miRNAs are differentially expressed in older adults with sarcopenic obesity.

Altered Circulating MicroRNA Profiles After Endurance Training: A Cohort Study of Ultramarathon Runners

Background

Despite the positive effects of endurance training on the cardiovascular (CV) system, excessive exercise induces not only physiological adaptations but also adverse changes in CV system, including the heart. We aimed to evaluate the selected miRNAs expression based on bioinformatic analysis and their changes before and after an ultramarathon run.

Materials and Methods

Cardiac tissue-specific targets were identified with the Tissue 2.0 database. Gene-gene interaction data were retrieved from the STRING app for Cytoscape. Twenty-three endurance athletes were recruited to the study. Athletes ran to completion (100 km) or exhaustion (52–91 km, median 74 km). All participants completed pre- and post-run testing. miRNAs expressions were measured both before and after the race.

Results

Enrichment analysis of the signaling pathways associated with the genes targeted by miRNAs selected for qRT-PCR validation (miR-1-3p, miR-126, miR-223, miR-125a-5p, miR-106a-5p, and miR-15a/b). All selected miRNAs showed overlap in regulation in pathways associated with cancer, IL-2 signaling, TGF-β signaling as well as BDNF signaling pathway. Analysis of metabolites revealed significant regulation of magnesium and guanosine triphosphate across analyzed miRNA targets. MiR-1-3p, miR-125a-5p, miR-126, and miR-223 expressions were measured in 23 experienced endurance athletes, before and after an ultramarathon wherein athletes ran to completion (100 km) or exhaustion (52–91 km, median 74 km). The expressions of miR-125a-5p, miR-126, and miR-223 were significantly increased after the race (p = 0.007, p = 0.001, p = 0.014, respectively). MiR-1-3p expression post-run showed a negative correlation with the post-run levels of high-sensitivity C-reactive protein (hs-CRP) (r = −0.632, p = 0.003). Higher miR-1-3p expression was found in runners, who finished the race under 10 h compared to runners who finished over 10 h (p = 0.001). Post-run miR-125a-5p expression showed a negative correlation with the peak lactate during the run (r = −0.576, p = 0.019).

Conclusion

Extreme physical activity, as exemplified by an ultramarathon, is associated with changes in circulating miRNAs’ expression related to inflammation, fibrosis, and cardiac muscle function. In particular, the negative correlations between miR-125a-5p and lactate concentrations, and miR-1-3p and hs-CRP, support their role in specific exercise-induced adaptation. Further studies are essential to validate the long-term effect of these observations.

MicroRNAs in Obesity-Associated Disorders: The Role of Exercise Training

Obesity is a worldwide epidemic affecting over 13% of the adult population and is defined by an excess of body fat that predisposes comorbidities. It is considered a multifactorial disease in which environmental and genetic factors interact, and it is a risk marker for cardiovascular disease. Lifestyle modifications remain the mainstay of treatment for obesity based on adequate diet and physical exercise. In addition, obesity is related to cardiovascular and skeletal muscle disorders, such as cardiac hypertrophy, microvascular rarefaction, and skeletal muscle atrophy. The discovery of obesity-involved molecular pathways is an important step to improve both the prevention and management of this disease. MicroRNAs (miRNAs) are a class of gene regulators which bind most commonly, but not exclusively, to the 3'-untranslated regions of messenger RNAs of protein-coding genes and negatively regulate their expression. Considerable effort has been made to identify miRNAs and target genes that predispose to obesity. Besides their intracellular function, recent studies have demonstrated that miRNAs can be exported or released by cells and circulate within the blood in a remarkably stable form. The discovery of circulating miRNAs opens up intriguing possibilities for the use of circulating miRNA patterns as biomarkers for obesity and cardiovascular diseases. The aim of this review is to provide an overview of the recent discoveries of the role played by miRNAs in the obese phenotype and associated comorbidities. Furthermore, we will discuss the role of exercise training on regulating miRNAs, indicating the mechanisms related to these alterations.

Transcriptional and Epigenetic Response to Sedentary Behavior and Physical Activity in Children and Adolescents: A Systematic Review

BACKGROUND

The links of sedentary behavior and physical activity with health outcomes in children and adolescents is well known. However, the molecular mechanisms involved are poorly understood. We aimed to synthesize the current knowledge of the association of sedentary behavior and physical activity (acute and chronic effects) with gene expression and epigenetic modifications in children and adolescents.

METHODS

PubMed, Web of Science, and Scopus databases were systematically searched until April 2022. A total of 15 articles were eligible for this review. The risk of bias assessment was performed using the Joanna Briggs Institute Critical Appraisal Tool for Systematic Reviews and/or a modified version of the Downs and Black checklist.

RESULTS

Thirteen studies used candidate gene approach, while only 2 studies performed high-throughput analyses. The candidate genes significantly linked to sedentary behavior or physical activity were: FOXP3, HSD11B2, IL-10, TNF-α, ADRB2, VEGF, HSP70, SOX, and GPX. Non-coding Ribonucleic acids (RNAs) regulated by sedentary behavior or physical activity were: miRNA-222, miRNA-146^a, miRNA-16, miRNA-126, miR-320^a, and long non-coding RNA MALAT1. These molecules are involved in inflammation, immune function, angiogenic process, and cardiovascular disease. Transcriptomics analyses detected thousands of genes that were altered following an acute bout of physical activity and are linked to gene pathways related to immune function, apoptosis, and metabolic diseases.

CONCLUSION

The evidence found to date is rather limited. Multidisciplinary studies are essential to characterize the molecular mechanisms in response to sedentary behavior and physical activity in the pediatric population. Larger cohorts and randomized controlled trials, in combination with multi-omics analyses, may provide the necessary data to bring the field forward.

SYSTEMATIC REVIEW REGISTRATION

[www.ClinicalTrials.gov], identifier [CRD42021235431].

Circulating microRNAs fluctuations in exercise-induced cardiac remodeling: A systematic review

MicroRNAs (miRNAs) are small non-coding RNAs that participate in gene expression regulation. It has been observed that circulating levels of miRNAs may fluctuate during exercise, showing numerous cardiac biological and physiological effects such as structural and functional adaptations. We aimed to provide an overview of the currently available information concerning the role of circulating miRNAs in cardiovascular adaptations in response to acute and/or chronic exercise training. Relevant studies published were searched in three databases: PubMed, Web of Science and Scopus. A combination of the following keywords was used: ("microRNA" OR "miRNA" OR "miR" AND "exercise" OR "training" OR "physical activity") AND "(heart hypertrophy" OR "cardiac remodeling" OR "cardiac muscle mass" OR "cardiac hypertrophy"). Only experimental studies, written in English and conducted in healthy individuals were included. Five articles met the inclusion criteria and were finally included in this systematic review after reviewing both title, abstract and full-text. A total of thirty-six circulating cardiac-related miRNAs were analyzed, but only five of them (miR-1, miR-133a, miR-146a, miR-206 and miR-221) were directly associated with cardiac adaptations parameters, while two of them (miR-1 and miR-133a) were related to cardiac hypertrophy. Most of them were upregulated immediately after a marathon and returned to basal levels at longer times. Therefore, we conclude that, although evidence is still limited, and long-term studies are needed to obtain more robust evidence, exercise is more likely to affect circulating cardiac-related miRNAs levels.

Plasma-Derived microRNAs Are Influenced by Acute and Chronic Exercise in Patients With Heart Failure With Reduced Ejection Fraction

Background: Exercise training improves VO₂peak in heart failure with reduced ejection fraction (HFrEF), but the effect is highly variable as it is dependent on peripheral adaptations. We evaluated changes in plasma-derived miRNAs by acute and chronic exercise to investigate whether these can mechanistically be involved in the variability of exercise-induced adaptations.

Methods: Twenty-five male HFrEF patients (left ventricular ejection fraction < 40%, New York Heart Association class ≥ II) participated in a 15-week combined strength and aerobic training program. The effect of training on plasma miRNA levels was compared to 21 male age-matched sedentary HFrEF controls. Additionally, the effect of a single acute exercise bout on plasma miRNA levels was assessed. Levels of 5 miRNAs involved in pathways relevant for exercise adaptation (miR-23a, miR-140, miR-146a, miR-191, and miR-210) were quantified using RT-qPCR and correlated with cardiopulmonary exercise test (CPET), echocardiographic, vascular function, and muscle strength variables.

Results: Expression levels of miR-146a decreased with training compared to controls. Acute exercise resulted in a decrease in miR-191 before, but not after training. Baseline miR-23a predicted change in VO₂peak independent of age and left ventricular ejection fraction (LVEF). Baseline miR-140 was independently correlated with change in load at the respiratory compensation point and change in body mass index, and baseline miR-146a with change in left ventricular mass index.

Conclusion: Plasma-derived miRNAs may reflect the underlying mechanisms of exercise-induced adaptation. In HFrEF patients, baseline miR-23a predicted VO₂peak response to training. Several miRNAs were influenced by acute or repeated exercise. These findings warrant exploration in larger patient populations and further mechanistic in vitro studies on their molecular involvement.

A Pilot Study of miRNA Expression Profile as a Liquid Biopsy for Full-Marathon Participants

Exosomal microRNA (miRNA) in plasma and urine has attracted attention as a novel diagnostic tool for pathological conditions. However, the mechanisms of miRNA dynamics in the exercise physiology field are not well understood in terms of monitoring sports performance. This pilot study aimed to reveal the miRNA dynamics in urine and plasma of full-marathon participants. Plasma and urine samples were collected from 26 marathon participants before, immediately after, 2 h after, and one day after a full marathon. The samples were pooled, and exosomal miRNAs were extracted and analyzed using next-generation sequencing. We determined that the exosomal miRNA expression profile changed under time dependency in full marathon. New uncharacterized exosomal miRNAs such as hsa-miR-582-3p and hsa-miR-199a-3p could be potential biomarkers reflecting physical stress of full marathon in plasma and urine. In addition, some muscle miRNAs in plasma and urine have supported the utility for monitoring physical stress. Furthermore, some inflammation-related exosomal miRNAs were useful only in plasma. These results suggest that these exosomal miRNAs in plasma and/or urine are highly sensitive biomarkers for physical stress in full marathons. Thus, our findings may yield valuable insights into exercise physiology.

Gene expression of angiogenesis and apoptotic factors in female BALB/c mice with breast cancer after eight weeks of aerobic training

OBJECTIVES

Breast cancer is the most common cancer in women, caused by a disorder in the angiogenesis and apoptosis process. Exercise can affect the process of angiogenesis and apoptosis in the tumor tissue. Thus, the aim of the present study was to investigate the changes in angiogenesis and apoptotic factors in mice with breast cancer after 8 weeks of exercise training.

MATERIALS AND METHODS

Sixteen females BALB/c mice (age: 3-5 weeks and weight: 17.1 ± 0.1 g) with breast cancer were randomly divided into two groups of aerobic training and control. The aerobic training included 8 weeks and 5 sessions per week of running with an intensity of 14-20 m.min-1. HIF-1α, VEGF, miR-21 and cytochrome C, Apaf-1, caspase-9, and caspase-3 gene expressions were examined by real-time PCR. Repeated measures ANOVA, Bonferroni's post hoc test, and independent samples t-test were used to analyze the data (P<0.05).

RESULTS

The results showed that aerobic training reduced the growth of tumor volume and significantly reduced miR-21 gene expression. Aerobic training also significantly increased the gene expression of HIF-1α, cytochrome C, Apaf-1, caspase-9, and caspase-3, while changes in VEGF gene expression were not statistically significant.

CONCLUSION

It appears that aerobic exercise training reduces tumor size and ameliorates breast cancer by reducing miR-21 gene expression, suppressing the apoptosis process, and reducing angiogenesis.

Epigenetic Regulation of Inflammatory Responses in the Context of Physical Activity

Epigenetic modifications occur in response to environmental changes and play a fundamental role in the regulation of gene expression. PA is found to elicit an inflammatory response, both from the innate and adaptive divisions of the immunological system. The inflammatory reaction is considered a vital trigger of epigenetic changes that in turn modulate inflammatory actions. The tissue responses to PA involve local and general changes. The epigenetic mechanisms involved include: DNA methylation, histone proteins modification and microRNA. All of them affect genetic expression in an inflammatory milieu in physical exercise depending on the magnitude of physiological stress experienced by the exerciser. PA may evoke acute or chronic biochemical and physiological responses and have a positive or negative immunomodulatory effect.

Marathon-Induced Cardiac Fatigue: A Review over the Last Decade for the Preservation of the Athletes' Health

AIM

To provide a state-of-the-art review of the last 10 years focusing on cardiac fatigue following a marathon.

METHODS

The PubMed, Bookshelf and Medline databases were queried during a time span of 10 years to identify studies that met the inclusion criteria. Twenty-four studies focusing only on the impact of marathons on the cardiac function and factors involved in cardiac fatigue were included in this review.

RESULTS

Sixteen studies focused on the impact of marathons on several biomarkers (e.g., C-reactive protein, cardiac troponin T). Seven studies focused on the left (LV) or right (RV) ventricular function following a marathon and employed cardiac magnetic resonance, echocardiography, myocardial speckle tracking and heart rate variability to analyze global and regional LV or RV mechanics and the impact of the autonomic nervous system on cardiac function. One study focused on serum profiling and its association with cardiac changes after a marathon.

CONCLUSIONS

This review reported a negligible impact of marathons on LV and RV systolic and contractile function but a negative impact on LV diastolic function in recreational runners. These impairments are often associated with acute damage to the myocardium. Thus, the advice of the present review to athletes is to adapt their training and have a regular medical monitoring to continue to run marathons while preserving their cardiac health.

Physical Exercise Training and Chagas Disease: Potential Role of MicroRNAs

A doença de Chagas (DC) é causada pelo Trypanosoma Cruzi. Esse parasita pode infectar vários órgãos do corpo humano, especialmente o coração, causando inflamação, fibrose, arritmias e remodelação cardíaca, e promovendo a cardiomiopatia chagásica crônica (CCC) no longo prazo. Entretanto, poucas evidências científicas elucidaram os mecanismos moleculares que regulam os processos fisiopatológicos nessa doença. Os microRNAs (miRNAs) são reguladores de expressão gênica pós-transcricional que modulam a sinalização celular, participando de mecanismos fisiopatológicos da DC, mas o entendimento dos miRNAs nessa doença é limitado. Por outro lado, há muitas evidências científicas demonstrando que o treinamento com exercício físico (TEF) modula a expressão de miRNAs, modificando a sinalização celular em indivíduos saudáveis. Alguns estudos também demonstram que o TEF traz benefícios para indivíduos com DC, porém esses não avaliaram as expressões de miRNA. Dessa forma, não há evidências demonstrando o papel do TEF na expressão dos miRNAs na DC. Portanto, essa revisão teve o objetivo de identificar os miRNAs expressos na DC que poderiam ser modificados pelo TEF.

Circulating microRNAs after a 24-h ultramarathon run in relation to muscle damage markers in elite athletes

Ultra-endurance sports are growing in popularity but can be associated with adverse health effects, such as exercise-induced muscle damage (EIMD), which can lead to exertional rhabdomyolysis. Circulating microRNAs (miRNAs) may be useful to approach the degree of EIMD. We aimed to (1) investigate the relevance of circulating miRNAs as biomarkers of muscle damage and (2) examine the acute response of skeletal/cardiac muscle and kidney biomarkers to a 24-h run in elite athletes. Eleven elite athletes participated in the 24-h run World Championships. Counter-movement jump (CMJ), creatine kinase (CK), myoglobin (Mb), creatinine (Cr), high-sensitive cardiac troponin T (hs-cTnT), and muscle-specific miRNA (myomiR) levels were measured before, immediately after, and 24 and 48h after the race. CMJ height was reduced immediately after the race (-84.0 ± 25.2%, p < 0.001) and remained low at 24 h (-43.6 ± 20.4%, p = 0.002). We observed high CK activity (53 239 ± 63 608 U/L, p < 0.001) immediately after the race, and it remained elevated 24h after (p < 0.01). Circulating myomiR levels (miR-1-3p, miR-133a-3p, miR-133b, miR-208a-3p, miR-208b-3p, and miR-499a-5p) were elevated immediately after the 24-h run (fold changes: 18-124,723, p<0.001) and significantly (p < 0.05) correlated or tended to significantly (p < 0.07) correlate with the reduction in CMJ height at 24 h. We found no significant correlation between CMJ height loss at 24 h and CK (p = 0.23) or Mb (p = 0.41) values. All elite ultramarathon runners included in our study were diagnosed with exertional rhabdomyolysis after the 24-h ultramarathon race. MyomiR levels may be useful to approach the degree of muscle damage.

Impacts of circulating microRNAs in exercise-induced vascular remodeling

Cardiovascular adaptation underlies all athletic training modalities, with a variety of factors contributing to overall response during exercise-induced stimulation. In this regard the role of circulating biomarkers is a well-established and invaluable tool for monitoring cardiovascular function. Specifically, novel biomarkers such as circulating cell free DNA and RNA are now becoming attractive tools for monitoring cardiovascular function with the advent of next generation technologies that can provide unprecedented precision and resolution of these molecular signatures, paving the way for novel diagnostic and prognostic avenues to better understand physiological remodeling that occurs in trained versus untrained states. In particular, microRNAs are a species of regulatory RNAs with pleiotropic effects on multiple pathways in tissue-specific manners. Furthermore, the identification of cell free microRNAs within peripheral circulation represents a distal signaling mechanism that is just beginning to be explored via a diversity of molecular and bioinformatic approaches. This article provides an overview of the emerging field of sports/performance genomics with a focus on the role of microRNAs as novel functional diagnostic and prognostic tools, and discusses present knowledge in the context of athletic vascular remodeling. This review concludes with current advantages and limitations, touching upon future directions and implications for applying contemporary systems biology knowledge of exercise-induced physiology to better understand how disruption can lead to pathology.

Gene Expression Signature in Patients With Symptomatic Peripheral Artery Disease

[Figure: see text].

Effects of physical activity on cell-to-cell communication during type 2 diabetes: A focus on miRNA signaling

Type 2 diabetes (TD2) is a progressive disease characterized by hyperglycemia that results from alteration in insulin secretion, insulin resistance, or both. A number of alterations involving different tissues and organs have been reported to the development and the progression of T2D, and more relevantly, through cell-to-cell communication pathways. Recent studies demonstrated that miRNAs are considerably implicated to cell-to-cell communication during T2D. Physical activity (PA) is associated with decreasing risks of developing T2D and acts as insulin-like factor. Cumulative evidence suggests that this effect could be mediated in part through improving insulin sensitivity in T2D and obese patients and modulating miRNAs synthesis and release in healthy patients. Therefore, the practice of PA should ideally be established before the initiation of T2D. This review describes cell-to-cell communications involved in the pathophysiology of T2D during PA.

The influence of lifestyle factors on miRNA expression and signal pathways: a review

The term 'lifestyle' includes different factors that contribute to the maintenance of a good health status. Increasing evidences suggest that lifestyle factors may influence epigenetic mechanisms, such as miRNAs expression. The dysregulation of miRNAs can modify the expression of genes and molecular pathways that may lead to functional alterations. This review summarizes human studies highlighting that diet, physical activity, smoking and alcohol consumption may affect the miRNA machinery and several biological functions. Most miRNAs are involved in molecular pathways that influence inflammation, cell cycle regulation and carcinogenesis resulting in the onset or progression of pathological conditions. Investigating these interactions will be pivotal for understanding the etiology of pathologic processes, the potential new treatment strategies and for preventing diseases.

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

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

Genetic test for the personalization of sport training

Genetic variants may contribute to confer elite athlete status. However, this does not mean that a person with favourable genetic traits would become a champion because multiple genetic interactions and epigenetic contributions coupled with confounding environmental factors shape the overall phenotype. This opens up a new area in sports genetics with respect to commercial genetic testing. The analysis of genetic polymorphisms linked to sport performance would provide insights into the potential of becoming an elite endurance or power performer. This mini-review aims to highlight genetic interactions that are associated with performance phenotypes and their potentials to be used as markers for talent identification and trainability.

MicroRNAs as Biomarkers of Systemic Changes in Response to Endurance Exercise-A Comprehensive Review

Endurance sports have an unarguably beneficial influence on cardiovascular health and general fitness. Regular physical activity is considered one of the most powerful tools in the prevention of cardiovascular disease. MicroRNAs are small particles that regulate the post-transcription gene expression. Previous studies have shown that miRNAs might be promising biomarkers of the systemic changes in response to exercise, before they can be detected by standard imaging or laboratory methods. In this review, we focused on four important physiological processes involved in adaptive changes to various endurance exercises (namely, cardiac hypertrophy, cardiac myocyte damage, fibrosis, and inflammation). Moreover, we discussed miRNAs’ correlation with cardiopulmonary fitness parameter (VO_2max). After a detailed literature search, we found that miR-1, miR-133, miR-21, and miR-155 are crucial in adaptive response to exercise.

Regulation of microRNAs in Satellite Cell Renewal, Muscle Function, Sarcopenia and the Role of Exercise

Sarcopenia refers to a condition of progressive loss of skeletal muscle mass and function associated with a higher risk of falls and fractures in older adults. Musculoskeletal aging leads to reduced muscle mass and strength, affecting the quality of life in elderly people. In recent years, several studies contributed to improve the knowledge of the pathophysiological alterations that lead to skeletal muscle dysfunction; however, the molecular mechanisms underlying sarcopenia are still not fully understood. Muscle development and homeostasis require a fine gene expression modulation by mechanisms in which microRNAs (miRNAs) play a crucial role. miRNAs modulate key steps of skeletal myogenesis including satellite cells renewal, skeletal muscle plasticity, and regeneration. Here, we provide an overview of the general aspects of muscle regeneration and miRNAs role in skeletal mass homeostasis and plasticity with a special interest in their expression in sarcopenia and skeletal muscle adaptation to exercise in the elderly.