Exosomes as Mediators of the Systemic Adaptations to Endurance Exercise

A MEPS-UHPLC-MS/MS analytical platform to detect isoprostanoids and specialized pro-resolving mediators in the urinary extracellular vesicles of mountain ultramarathon runners

Oxylipins are powerful signalling compounds derived from polyunsaturated fatty acids (PUFAs) and involved in regulating the immune system response. A mass spectrometry-based method was developed and validated for the targeted profiling of 52 oxylipins (e.g., isoprostanoids, prostaglandins, epoxy- and hydroxy-fatty acids, specialized pro-resolving mediators) and 4 PUFAs in small urinary extracellular vesicles (uEVs). Ultrasound-assisted extraction using a 50:50 v/v MeOH:H2O mixture ensured optimal analytical performances. Limits of detection ranged between 10 and 400 pg/mL for oxylipins and 0.10-3 ng/mL for PUFAs. Satisfactory recoveries (85-116 %) and good intra- and inter-day precisions (RSD ≤15 %) were obtained for all the analytes. The reliability of the procedure was tested in a real case scenario by monitoring ultramarathon runners during the world Tor des Géants® (TDG) race. Both F2- and E2-isoprostanes were detected in small uEVs of the ultramarathon runners, suggesting the onset of an oxidant insult. 5-F2t-IsoP exhibited significant pre- to post-race variations, thus potentially representing a non-invasive marker of in-vivo lipid peroxidation. The presence of specialized pro-resolving mediators suggests the activation of pro-resolution signalling cascade resolving inflammation. These outcomes may help manage post-exercise recovery and improve training.

The effects of extracellular vesicles and their cargo on metabolism and its adaptation to physical exercise in insulin resistance and type 2 diabetes

Lifestyle modification represents the first-line strategy for the prevention and treatment of type 2 diabetes mellitus (T2DM), which is frequently associated with obesity and characterized by defective pancreatic insulin secretion and/or insulin resistance. Exercise training is an essential component of lifestyle modification and has been shown to ameliorate insulin resistance by reducing body fat mass and by enhancing skeletal muscle mitochondrial biogenesis and insulin-independent glucose uptake. Additionally, exercising stimulates the release of exerkines such as metabolites or cytokines, but also long non-coding RNA, microRNAs, cell-free DNA (cf-DNA), and extracellular vesicles (EVs), which contribute to inter-tissue communication. There is emerging evidence that EV number and content are altered in obesity and T2DM and may be involved in several metabolic processes, specifically either worsening or improving insulin resistance. This review summarizes the current knowledge on the metabolic effects of exercise training and on the potential role of humoral factors and EV as new biomarkers for early diagnosis and tailored treatment of T2DM.

Molecular insights of exercise therapy in disease prevention and treatment

Despite substantial evidence emphasizing the pleiotropic benefits of exercise for the prevention and treatment of various diseases, the underlying biological mechanisms have not been fully elucidated. Several exercise benefits have been attributed to signaling molecules that are released in response to exercise by different tissues such as skeletal muscle, cardiac muscle, adipose, and liver tissue. These signaling molecules, which are collectively termed exerkines, form a heterogenous group of bioactive substances, mediating inter-organ crosstalk as well as structural and functional tissue adaption. Numerous scientific endeavors have focused on identifying and characterizing new biological mediators with such properties. Additionally, some investigations have focused on the molecular targets of exerkines and the cellular signaling cascades that trigger adaption processes. A detailed understanding of the tissue-specific downstream effects of exerkines is crucial to harness the health-related benefits mediated by exercise and improve targeted exercise programs in health and disease. Herein, we review the current in vivo evidence on exerkine-induced signal transduction across multiple target tissues and highlight the preventive and therapeutic value of exerkine signaling in various diseases. By emphasizing different aspects of exerkine research, we provide a comprehensive overview of (i) the molecular underpinnings of exerkine secretion, (ii) the receptor-dependent and receptor-independent signaling cascades mediating tissue adaption, and (iii) the clinical implications of these mechanisms in disease prevention and treatment.

Environmental pollutants and exosomes: A new paradigm in environmental health and disease

This study investigates the intricate interplay between environmental pollutants and exosomes, shedding light on a novel paradigm in environmental health and disease. Cellular stress, induced by environmental toxicants or disease, significantly impacts the production and composition of exosomes, crucial mediators of intercellular communication. The heat shock response (HSR) and unfolded protein response (UPR) pathways, activated during cellular stress, profoundly influence exosome generation, cargo sorting, and function, shaping intercellular communication and stress responses. Environmental pollutants, particularly lipophilic ones, directly interact with exosome lipid bilayers, potentially affecting membrane stability, release, and cellular uptake. The study reveals that exposure to environmental contaminants induces significant changes in exosomal proteins, miRNAs, and lipids, impacting cellular function and health. Understanding the impact of environmental pollutants on exosomal cargo holds promise for biomarkers of exposure, enabling non-invasive sample collection and real-time insights into ongoing cellular responses. This research explores the potential of exosomal biomarkers for early detection of health effects, assessing treatment efficacy, and population-wide screening. Overcoming challenges requires advanced isolation techniques, standardized protocols, and machine learning for data analysis. Integration with omics technologies enhances comprehensive molecular analysis, offering a holistic understanding of the complex regulatory network influenced by environmental pollutants. The study underscores the capability of exosomes in circulation as promising biomarkers for assessing environmental exposure and systemic health effects, contributing to advancements in environmental health research and disease prevention.

The Landscape of Exosomes Biogenesis to Clinical Applications

Exosomes are extracellular vesicles that originate from various cells and mediate intercellular communication, altering the behavior or fate of recipient cells. They carry diverse macromolecules, such as lipids, proteins, carbohydrates, and nucleic acids. Environmental stressors can change the exosomal contents of many cells, making them useful for diagnosing many chronic disorders, especially neurodegenerative, cardiovascular, cancerous, and diabetic diseases. Moreover, exosomes can be engineered as therapeutic agents to modulate disease processes. State-of-art techniques are employed to separate exosomes including ultracentrifugation, size-exclusion chromatography and immunoaffinity. However, modern technologies such as aqueous two-phase system as well as microfluidics are gaining attention in the recent years. The article highlighted the composition, biogenesis, and implications of exosomes, as well as the standard and novel methods for isolating them and applying them as biomarkers and therapeutic cargo carriers.

Advancing cancer cachexia diagnosis with -omics technology and exercise as molecular medicine

Muscle atrophy exacerbates disease outcomes and increases mortality, whereas the preservation of skeletal muscle mass and function play pivotal roles in ensuring long-term health and overall quality-of-life. Muscle atrophy represents a significant clinical challenge, involving the continued loss of muscle mass and strength, which frequently accompany the development of numerous types of cancer. Cancer cachexia is a highly prevalent multifactorial syndrome, and although cachexia is one of the main causes of cancer-related deaths, there are still no approved management strategies for the disease. The etiology of this condition is based on the upregulation of systemic inflammation factors and catabolic stimuli, resulting in the inhibition of protein synthesis and enhancement of protein degradation. Numerous necessary cellular processes are disrupted by cachectic pathology, which mediate intracellular signalling pathways resulting in the net loss of muscle and organelles. However, the exact underpinning molecular mechanisms of how these changes are orchestrated are incompletely understood. Much work is still required, but structured exercise has the capacity to counteract numerous detrimental effects linked to cancer cachexia. Primarily through the stimulation of muscle protein synthesis, enhancement of mitochondrial function, and the release of myokines. As a result, muscle mass and strength increase, leading to improved mobility, and quality-of-life. This review summarises existing knowledge of the complex molecular networks that regulate cancer cachexia and exercise, highlighting the molecular interplay between the two for potential therapeutic intervention. Finally, the utility of mass spectrometry-based proteomics is considered as a way of establishing early diagnostic biomarkers of cachectic patients.

Acute exercise-induced release of innate immune proteins via small extracellular vesicles changes with aerobic fitness and age

AIM

Physical exercise triggers the secretion of small extracellular vesicles (sEVs) into the circulation in humans, enabling signalling crosstalk between tissues. Exercise-derived EVs and their cargo have been proposed to mediate adaptations to exercise; however, our understanding of how exercise-derived EV protein cargo is modulated by factors such as aerobic fitness and age of an individual is currently unknown. Here, we examined the circulating sEV proteome following aerobic exercise in healthy males of different ages and aerobic fitness to understand exercise-induced EV response during the aging process.

METHODS

Twenty-eight healthy men completed a bout of 20-min cycling exercise at 70% estimated VO2peak . Small EVs were isolated from blood samples collected before and immediately after exercise, and then quantified using particle analysis and Western blotting. Small EV proteome was examined using quantitative proteomic analysis.

RESULTS

We identified a significant increase in 13 proteins in small plasma EVs following moderate-to-vigorous intensity exercise. We observed distinct changes in sEV proteome after exercise in young, mature, unfit, and fit individuals, highlighting the impact of aerobic fitness and age on sEV protein secretion. Functional enrichment and pathway analysis identified that the majority of the significantly altered sEV proteins are associated with the innate immune system, including proteins known to be damage-associated molecular patterns (DAMPs).

CONCLUSION

Together, our findings suggest that exercise-evoked acute stress can positively challenge the innate immune system through the release of signalling molecules such as DAMPs in sEVs, proposing a novel EV-based mechanism for moderate-to-vigorous intensity exercise in immune surveillance pathways.

Exosome-Mediated Impact on Systemic Metabolism

Exosomes are small extracellular vesicles that carry lipids, proteins, and microRNAs (miRNAs). They are released by all cell types and can be found not only in circulation but in many biological fluids. Exosomes are essential for interorgan communication because they can transfer their contents from donor to recipient cells, modulating cellular functions. The miRNA content of exosomes is responsible for most of their biological effects, and changes in exosomal miRNA levels can contribute to the progression or regression of metabolic diseases. As exosomal miRNAs are selectively sorted and packaged into exosomes, they can be useful as biomarkers for diagnosing diseases. The field of exosomes and metabolism is expanding rapidly, and researchers are consistently making new discoveries in this area. As a result, exosomes have great potential for a next-generation drug delivery platform for metabolic diseases.

Small peptides: could they have a big role in metabolism and the response to exercise?

Exercise is a powerful non-pharmacological intervention for the treatment and prevention of numerous chronic diseases. Contracting skeletal muscles provoke widespread perturbations in numerous cells, tissues and organs, which stimulate multiple integrated adaptations that ultimately contribute to the many health benefits associated with regular exercise. Despite much research, the molecular mechanisms driving such changes are not completely resolved. Technological advancements beginning in the early 1960s have opened new avenues to explore the mechanisms responsible for the many beneficial adaptations to exercise. This has led to increased research into the role of small peptides (<100 amino acids) and mitochondrially derived peptides in metabolism and disease, including those coded within small open reading frames (sORFs; coding sequences that encode small peptides). Recently, it has been hypothesized that sORF-encoded mitochondrially derived peptides and other small peptides play significant roles as exercise-sensitive peptides in exercise-induced physiological adaptation. In this review, we highlight the discovery of mitochondrially derived peptides and newly discovered small peptides involved in metabolism, with a specific emphasis on their functions in exercise-induced adaptations and the prevention of metabolic diseases. In light of the few studies available, we also present data on how both single exercise sessions and exercise training affect expression of sORF-encoded mitochondrially derived peptides. Finally, we outline numerous research questions that await investigation regarding the roles of mitochondrially derived peptides in metabolism and prevention of various diseases, in addition to their roles in exercise-induced physiological adaptations, for future studies.

Exercise-Intervened Endothelial Progenitor Cell Exosomes Protect N2a Cells by Improving Mitochondrial Function

We have recently demonstrated that exosomal communication between endothelial progenitor cells (EPCs) and brain endothelial cells is compromised in hypertensive conditions, which might contribute to the poor outcomes of stroke subjects with hypertension. The present study investigated whether exercise intervention can regulate EPC-exosome (EPC-EX) functions in hypertensive conditions. Bone marrow EPCs from sedentary and exercised hypertensive transgenic mice were used for generating EPC-EXs, denoted as R-EPC-EXs and R-EPC-EXET. The exosomal microRNA profile was analyzed, and EX functions were determined in a co-culture system with N2a cells challenged by angiotensin II (Ang II) plus hypoxia. EX-uptake efficiency, cellular survival ability, reactive oxygen species (ROS) production, mitochondrial membrane potential, and the expressions of cytochrome c and superoxide-generating enzyme (Nox4) were assessed. We found that (1) exercise intervention improves the uptake efficiency of EPC-EXs by N2a cells. (2) exercise intervention restores miR-27a levels in R-EPC-EXs. (3) R-EPC-EXET improved the survival ability and reduced ROS overproduction in N2a cells challenged with Ang II and hypoxia. (4) R-EPC-EXET improved the mitochondrial membrane potential and decreased cytochrome c and Nox4 levels in Ang II plus hypoxia-injured N2a cells. All these effects were significantly reduced by miR-27a inhibitor. Together, these data have demonstrated that exercise-intervened EPC-EXs improved the mitochondrial function of N2a cells in hypertensive conditions, which might be ascribed to their carried miR-27a.

Translational studies of exosomes in sports medicine - a mini-review

This review in sports medicine focuses on the critical role of exosomes in managing chronic conditions and enhancing athletic performance. Exosomes, small vesicles produced by various cells, are essential for cellular communication and transporting molecules like proteins and nucleic acids. Originating from the endoplasmic reticulum, they play a vital role in modulating inflammation and tissue repair. Their significance in sports medicine is increasingly recognized, particularly in healing athletic injuries, improving articular cartilage lesions, and osteoarthritic conditions by modulating cellular behavior and aiding tissue regeneration. Investigations also highlight their potential in boosting athletic performance, especially through myocytes-derived exosomes that may enhance adaptability to physical training. Emphasizing a multidisciplinary approach, this review underlines the need to thoroughly understand exosome biology, including their pathways and classifications, to fully exploit their therapeutic potential. It outlines future directions in sports medicine, focusing on personalized treatments, clinical evaluations, and embracing technological advancements. This research represents a frontier in using exosomes to improve athletes' health and performance capabilities.

Modulation of MicroRNAs and Exosomal MicroRNAs after Dietary Interventions for Obesity and Insulin Resistance: A Narrative Review

MicroRNAs (miRNAs) are small noncoding RNAs approximately 22 nucleotides in length. Their main function is to regulate gene expression at the posttranscriptional level by inhibiting the translation of messenger RNAs (mRNAs). miRNAs originate in the cell nucleus from specific genes, where they can perform their function. However, they can also be found in serum, plasma, or other body fluids travelling within vesicles called exosomes and/or bound to proteins or other particles such as lipoproteins. miRNAs can form complexes outside the cell where they are synthesized, mediating paracrine and endocrine communication between different tissues. In this way, they can modulate the gene expression and function of distal cells. It is known that the expression of miRNAs can be affected by multiple factors, such as the nutritional or pathological state of the individual, or even in conditions such as obesity, insulin resistance, or after any dietary intervention. In this review, we will analyse miRNAs whose expression and circulation are affected in conditions of obesity and insulin resistance, as well as the changes generated after a dietary intervention, with the purpose of identifying new possible biomarkers of early response to nutritional treatment in these conditions.

Exercise, healthy ageing, and the potential role of small extracellular vesicles

Extracellular vesicles (EVs) can be released from most cells in the body and act as intercellular messengers transferring information in their cargo to affect cellular function. A growing body of evidence suggests that a subset of EVs, referred to here as 'small extracellular vesicles' (sEVs), can accelerate or slow the processes of ageing and age-related diseases dependent on their molecular cargo and cellular origin. Continued exploration of the vast complexity of the sEV cargo aims to further characterise these systemic vehicles that may be targeted to ameliorate age-related pathologies. Marked progress in the development of mass spectrometry-based technologies means that it is now possible to characterise a significant proportion of the proteome of sEVs (surface and cargo) via unbiased proteomics. This information is vital for identifying biomarkers and the development of sEV-based therapeutics in the context of ageing. Although exercise and physical activity are prominent features in maintaining health in advancing years, the mechanisms responsible are unclear. A potential mechanism by which plasma sEVs released during exercise could influence ageing and senescence is via the increased delivery of cargo proteins that function as antioxidant enzymes or inhibitors of senescence. These have been observed to increase in sEVs following acute and chronic exercise, as identified via independent interrogation of high coverage, publicly available proteomic datasets. Establishing tropism and exchange of functionally active proteins by these processes represents a promising line of enquiry in implicating sEVs as biologically relevant mediators of the ageing process.

Single vesicle analysis reveals the release of tetraspanin positive extracellular vesicles into circulation with high intensity intermittent exercise

Small extracellular vesicles (sEVs) are released from all cell types and participate in the intercellular exchange of proteins, lipids, metabolites and nucleic acids. Proteomic, flow cytometry and nanoparticle tracking analyses suggest sEVs are released into circulation with exercise. However, interpretation of these data may be influenced by sources of bias introduced by different analytical approaches. Seven healthy participants carried out a high intensity intermittent training (HIIT) cycle protocol consisting of 4 × 30 s at a work-rate corresponding to 200% of individual max power (watts) interspersed by 4.5 min of active recovery. EDTA-treated blood was collected before and immediately after the final effort. Platelet-poor (PPP) and platelet-free (PFP) plasma was derived by one or two centrifugal spins at 2500 g, respectively (15 min, room temperature). Platelets were counted on an automated haemocytometer. Plasma samples were assessed with the Exoview R100 platform, which immobilises sEVs expressing common tetraspanin markers CD9, CD63, CD81 and CD41a on microfluidic chips and with the aid of fluorescence imaging, counts their abundance at a single sEV resolution, importantly, without a pre-isolation step. There was a lower number of platelets in the PFP than PPP, which was associated with a lower number of CD9, CD63 and CD41a positive sEVs. HIIT induced an increase in fluorescence counts in CD9, CD63 and CD81 positive sEVs in both PPP and PFP. These data support the concept that sEVs are released into circulation with exercise. Furthermore, platelet-free plasma is the preferred, representative analyte to study sEV dynamics and phenotype during exercise. KEY POINTS: Small extracellular vesicles (sEV) are nano-sized particles containing protein, metabolites, lipid and RNA that can be transferred from cell to cell. Previous findings implicate that sEVs are released into circulation with exhaustive, aerobic exercise, but since there is no gold standard method to isolate sEVs, these findings may be subject to bias introduced by different approaches. Here, we use a novel method to immobilise and image sEVs, at single-vesicle resolution, to show sEVs are released into circulation with high intensity intermittent exercise. Since platelet depletion of plasma results in a reduction in sEVs, platelet-free plasma is the preferred analyte to examine sEV dynamics and phenotype in the context of exercise.

Converging protective pathways: Exploring the linkage between physical exercise, extracellular vesicles and oxidative stress

Physical Exercise (EXR) has been shown to have numerous beneficial effects on various systems in the human body. It leads to a decrease in the risk of mortality from chronic diseases, such as cardiovascular disease, cancer, metabolic and central nervous system disorders. EXR results in improving cardiovascular fitness, cognitive function, immune activity, endocrine action, and musculoskeletal health. These positive effects make EXR a valuable intervention for promoting overall health and well-being in individuals of all ages. These beneficial effects are partially mediated by the role of the regular EXR in the adaptation to redox homeostasis counteracting the sudden increase of ROS, the hallmark of many chronic diseases. EXR can trigger the release of numerous humoral factors, e.g. protein, microRNA (miRs), and DNA, that can be shuttled as cargo of Extracellular vesicles (EVs). EVs show different cargo modification after oxidative stress stimuli as well as after EXR. In this review, we aim to highlight the main studies on the role of EVs released during EXR and oxidative stress conditions in enhancing the antioxidant enzymes pathway and in the decrease of oxidative stress environment mediated by their cargo.

Fatiguing freestyle swimming modifies miRNA profiles of circulating extracellular vesicles in athletes

Extracellular vesicles (EVs) are secreted by various tissues and cells under normal physiological or pathological conditions. Exercise-induced EVs may be involved in the adaptation of exercise-induced fatigue. The 1500-m freestyle is the longest pool-based swimming event in the Olympic Games, and there is a paucity of information regarding changes in the miRNA profiles of circulating EVs after a single session of fatiguing swimming. In this study, 13 male freestyle swimmers conducted a fatiguing 1500-m freestyle swimming session at the speed of their best previously recorded swimming performance. Fasting venous blood was collected before and after the swimming session for analysis. 70 miRNAs from the circulating EVs were found to be differentially expressed after the fatiguing 1500-m freestyle swimming session, among which 45 and 25 miRNAs were up-regulated and down-regulated, respectively. As for the target genes of five miRNAs (miR-144-3p, miR-145-3p, miR-509-5p, miR-891b, and miR-890) with the largest expression-fold variation, their functional enrichment analysis demonstrated that the target genes were involved in the regulation of long-term potentiation (LTP), vascular endothelial growth factor (VEGF), glutathione metabolism pathway, dopaminergic synapse, signal transmission, and other biological processes. In summary, these findings reveal that a single session of fatiguing swimming modifies the miRNAs profiles of the circulating EVs, especially miR-144-3p, miR-145-3p, miR-509-5p, miR-891b, and miR-890, which clarifies new mechanisms for the adaptation to a single session of fatiguing exercise from the perspective of EV-miRNAs.

The role of exercise parameters on small extracellular vesicles and microRNAs cargo in preventing neurodegenerative diseases

Physical activity (PA), which includes exercise, can reduce the risk of developing various non-communicable diseases, including neurodegenerative diseases (NDs), and mitigate their adverse effects. However, the mechanisms underlying this ability are not yet fully understood. Among several possible mechanisms proposed, such as the stimulation of brain-derived neurotrophic factor (BDNF), endothelial nitric oxide synthase (eNOS), insulin-like growth factor-1 (IGF-1), vascular endothelial growth factor (VEGF), and nerve growth factor (NGF), the possible involvement of particular vesicular structures enclosed in lipid membranes known as extracellular vesicles (EVs) has recently been investigated. These EVs would appear to exert a paracrine and systemic action through their ability to carry various molecules, particularly so-called microRNAs (miRNAs), performing a function as mediators of intercellular communication. Interestingly, EVs and miRNAs are differentially expressed following PA, but evidence on how different exercise parameters may differentially affect EVs and the miRNAs they carry is still scarce. In this review we summarized the current human findings on the effects of PA and different exercise parameters exerted on EVs and their cargo, focusing on miRNAs molecules, and discussing how this may represent one of the biological mechanisms through which exercise contributes to preventing and slowing NDs.

Novel insights regarding the role of noncoding RNAs in diabetes

Diabetes mellitus (DM) is a group of metabolic disorders defined by hyperglycemia induced by insulin resistance, inadequate insulin secretion, or excessive glucagon secretion. In 2021, the global prevalence of diabetes is anticipated to be 10.7% (537 million people). Noncoding RNAs (ncRNAs) appear to have an important role in the initiation and progression of DM, according to a growing body of research. The two major groups of ncRNAs implicated in diabetic disorders are miRNAs and long noncoding RNAs. miRNAs are single-stranded, short (17–25 nucleotides), ncRNAs that influence gene expression at the post-transcriptional level. Because DM has reached epidemic proportions worldwide, it appears that novel diagnostic and therapeutic strategies are required to identify and treat complications associated with these diseases efficiently. miRNAs are gaining attention as biomarkers for DM diagnosis and potential treatment due to their function in maintaining physiological homeostasis via gene expression regulation. In this review, we address the issue of the gradually expanding global prevalence of DM by presenting a complete and up-to-date synopsis of various regulatory miRNAs involved in these disorders. We hope this review will spark discussion about ncRNAs as prognostic biomarkers and therapeutic tools for DM. We examine and synthesize recent research that used novel, high-throughput technologies to uncover ncRNAs involved in DM, necessitating a systematic approach to examining and summarizing their roles and possible diagnostic and therapeutic uses.

Running from stress: a perspective on the potential benefits of exercise-induced small extracellular vesicles for individuals with major depressive disorder

Aerobic exercise promotes beneficial effects in the brain including increased synaptic plasticity and neurogenesis and regulates neuroinflammation and stress response via the hypothalamic-pituitary-adrenal axis. Exercise can have therapeutic effects for numerous brain-related pathologies, including major depressive disorder (MDD). Beneficial effects of aerobic exercise are thought to be mediated through the release of "exerkines" including metabolites, proteins, nucleic acids, and hormones that communicate between the brain and periphery. While the specific mechanisms underlying the positive effects of aerobic exercise on MDD have not been fully elucidated, the evidence suggests that exercise may exert a direct or indirect influence on the brain via small extracellular vesicles which have been shown to transport signaling molecules including "exerkines" between cells and across the blood-brain barrier (BBB). sEVs are released by most cell types, found in numerous biofluids, and capable of crossing the BBB. sEVs have been associated with numerous brain-related functions including neuronal stress response, cell-cell communication, as well as those affected by exercise like synaptic plasticity and neurogenesis. In addition to known exerkines, they are loaded with other modulatory cargo such as microRNA (miRNA), an epigenetic regulator that regulates gene expression levels. How exercise-induced sEVs mediate exercise dependent improvements in MDD is unknown. Here, we perform a thorough survey of the current literature to elucidate the potential role of sEVs in the context of neurobiological changes seen with exercise and depression by summarizing studies on exercise and MDD, exercise and sEVs, and finally, sEVs as they relate to MDD. Moreover, we describe the links between peripheral sEV levels and their potential for infiltration into the brain. While literature suggests that aerobic exercise is protective against the development of mood disorders, there remains a scarcity of data on the therapeutic effects of exercise. Recent studies have shown that aerobic exercise does not appear to influence sEV size, but rather influence their concentration and cargo. These molecules have been independently implicated in numerous neuropsychiatric disorders. Taken together, these studies suggest that concentration of sEVs are increased post exercise, and they may contain specifically packaged protective cargo representing a novel therapeutic for MDD.

Exercise-primed extracellular vesicles improve cell-matrix adhesion and chondrocyte health

Extracellular vesicles (EVs) have been suggested to transmit the health-promoting effects of exercise throughout the body. Yet, the mechanisms by which beneficial information is transmitted from extracellular vesicles to recipient cells are poorly understood, precluding a holistic understanding of how exercise promotes cellular and tissue health. In this study, using articular cartilage as a model, we introduced a network medicine paradigm to simulate how exercise facilitates communication between circulating EVs and chondrocytes, the cells resident in articular cartilage. Using the archived small RNA-seq data of EV before and after aerobic exercise, microRNA regulatory network analysis based on network propagation inferred that circulating EVs activated by aerobic exercise perturb chondrocyte-matrix interactions and downstream cellular aging processes. Building on the mechanistic framework identified through computational analyses, follow up experimental studies interrogated the direct influence of exercise on EV-mediated chondrocyte-matrix interactions. We found that pathogenic matrix signaling in chondrocytes was abrogated in the presence of exercise-primed EVs, restoring a more youthful phenotype, as determined by chondrocyte morphological profiling and evaluation of chondrogenicity. Epigenetic reprograming of the gene encoding the longevity protein, α-Klotho, mediated these effects. These studies provide mechanistic evidence that exercise transduces rejuvenation signals to circulating EVs, endowing EVs with the capacity to ameliorate cellular health even in the presence of an unfavorable microenvironmental signals.

Walking 200 min per day keeps the bariatric surgeon away

Exercise and increased physical activity are vital components of the standard treatment guidelines for many chronic diseases such as diabetes, obesity and cardiovascular disease. Although strenuous exercise cannot be recommended to people with numerous chronic conditions, walking is something most people can perform. In comparison to high-intensity training, the metabolic consequences of low-intensity walking have been less well studied. We present here a feasibility study of a subject who performed an exercise intervention of low-intensity, non-fatiguing walking on a deskmill/treadmill for 200 min daily, approximately the average time a German spends watching television per day. This low-impact physical activity has the advantages that it can be done while performing other tasks such as reading or watching TV, and it can be recommended to obese patients or patients with heart disease. We find that this intervention led to substantial weight loss, comparable to that of bariatric surgery. To study the metabolic changes caused by this intervention, we performed an in-depth metabolomic profiling of the blood both directly after walking to assess the acute changes, as well as 1.5 days after physical activity to identify the long-term effects that persist. We find changes in acylcarnitine levels suggesting that walking activates fatty acid beta oxidation, and that this mitochondrial reprogramming is still visible 1.5 days post-walking. We also find that walking mildly increases gut permeability, leading to increased exposure of the blood to metabolites from the gut microbiome. Overall, these data provide a starting point for designing future intervention studies with larger cohorts.

Steady-state redox status in circulating extracellular vesicles: A proof-of-principle study on the role of fitness level and short-term aerobic training in healthy young males

Considering the role of redox homeostasis in exercise-induced signaling and adaptation, this study focuses on the exercise training-related intercellular communication of redox status mediated by circulating extracellular vesicles (EVs). 19 healthy young males were divided into trained (TG, 7) and untrained (UG, 12) subjects based on their VO_2MAX. The UG subjects were further randomly distributed in experimental (UG_EX, N = 7) and control (UG_CTRL, N = 5) groups. The steady state of plasma EVs in TG and UG_EX have been characterized for total number and size, as well as cargo redox status (antioxidants, transcription factors, HSPs) before, 3 and 24 h after a single bout of aerobic exercise (30', 70% HRM). Plasma EVs from UG_EX and UG_CTRL have been further characterized after 24 h from the last session of a 5-day consecutive aerobic training or no training, respectively. No differences were detected in the EVs' size and distribution at baseline in TG and UG_EX (p>0.05), while the EVs cargo of UG_EX showed a significantly higher concentration of protein carbonyl, Catalase, SOD2, and HSF1 compared to TG (p<0.05). 5 days of consecutive aerobic training in UG_EX did not determine major changes in the steady-state number and size of EVs. The post-training levels of protein carbonyl, HSF1, Catalase, and SOD2 in EVs cargo of UG_EX resulted significantly lower compared with UG_EX before training and UG_CTRL, resembling the steady-state levels in circulating EVs of TG subjects. Altogether, these preliminary data indicate that individual aerobic capacity influences the redox status of circulating EVs, and that short-term aerobic training impacts the steady-state redox status of EVs. Taking this pilot study as a paradigm for physio-pathological stimuli impacting redox homeostasis, our results offer new insights into the utilization of circulating EVs as biomarkers of exercise efficacy and of early impairment of oxidative-stress related diseases.

Exercise-Induced Fibroblast Growth Factor-21: A Systematic Review and Meta-Analysis

This systematic review aimed to synthesize and quantify the results of the studies investigating the changes in fibroblast growth factor-21 (FGF-21) induced by exercise. We searched for studies that did not differentiate between patients and healthy adults but compared them before and after exercise and with and without exercise. For quality assessment, the risk-of-bias assessment tool for nonrandomized studies and the Cochrane risk-of-bias tool were used. A quantitative analysis was performed using the standardized mean difference (SMD) and random-effects model in RevMan 5.4. A total of 94 studies were searched in international electronic databases, and after screening, 10 studies with 376 participants were analyzed. Compared with no exercise, there was a significant increase in the FGF-21 levels from before to after exercise (SMD = 1.05, 95% confidence interval (CI), 0.21 to 1.89). The changes in FGF-21 levels in the exercise group showed a significant difference from the levels in the controls. The results of the random-effects model were as follows: SMD = 1.12; 95% CI, -0.13 to 2.37. While the data on acute exercise were not synthesized in this study, FGF-21 levels generally increased after chronic exercise compared with no exercise.

Defining the influence of size-exclusion chromatography fraction window and ultrafiltration column choice on extracellular vesicle recovery in a skeletal muscle model

Extracellular vesicles (EVs) have the potential to provide new insights into skeletal muscle (SM) physiology and pathophysiology. However, current isolation protocols often do not eliminate co-isolated components such as lipoproteins and RNA binding proteins that could confound outcomes and hinder downstream clinical translation. In this study, we validated an EV isolation protocol that combined size-exclusion chromatography (SEC) with ultrafiltration (UF) to increase sample throughput, scalability and purity, while providing the very first analysis of the effects of UF column choice and fraction window on EV recovery. C2C12 myotube conditioned medium was pre-concentrated using either Amicon® Ultra 15 or Vivaspin®20 100 KDa UF columns and processed by SEC (IZON, qEV 70 nm). The resulting thirty fractions obtained were individually analysed to identify an optimal fraction window for EV recovery. The EV marker TSG101 could be detected from fractions 5 to 14, while CD9 and Annexin A2 only up to fraction 6. ApoA1+ lipoprotein co-isolates were detected from fraction 6 onwards for both protocols. Strikingly, Amicon and Vivaspin UF concentration protocols led to qualitative and quantitative variations in EV marker profiles and purity. Eliminating lipoprotein co-isolation by reducing the SEC fraction window resulted in a net loss of particles, but increased measures of sample purity and had only a negligible impact on the presence of EV marker proteins. In conclusion, our study developed an effective UF+SEC protocol for the isolation of EVs based on sample purity (fractions 1-5) and total EV abundance (fractions 2-10). We provide evidence to demonstrate that the choice of UF column can affect the composition of the resulting EV preparation and needs to be considered when being applied in EV isolation studies in SM. The resulting protocols will be valuable in isolating highly pure EV preparations for applications in a range of therapeutic and diagnostic studies.

Modulation of the Circulating Extracellular Vesicles in Response to Different Exercise Regimens and Study of Their Inflammatory Effects

Exercise-released extracellular vesicles (EVs) are emerging as a novel class of exerkines that promotes systemic beneficial effects. However, slight differences in the applied exercise protocols in terms of mode, intensity and duration, as well as the need for standardized protocols for EV isolation, make the comparison of the studies in the literature extremely difficult. This work aims to investigate the EV amount and EV-associated miRNAs released in circulation in response to different physical exercise regimens. Healthy individuals were subjected to different exercise protocols: acute aerobic exercise (AAE) and training (AT), acute maximal aerobic exercise (AMAE) and altitude aerobic training (AAT). We found a tendency for total EVs to increase in the sedentary condition compared to trained participants following AAE. Moreover, the cytofluorimetric analysis showed an increase in CD81⁺/SGCA⁺/CD45^- EVs in response to AAE. Although a single bout of moderate/maximal exercise did not impact the total EV number, EV-miRNA levels were affected as a result. In detail, EV-associated miR-206, miR-133b and miR-146a were upregulated following AAE, and this trend appeared intensity-dependent. Finally, THP-1 macrophage treatment with exercise-derived EVs induced an increase of the mRNAs encoding for IL-1β, IL-6 and CD163 using baseline and immediately post-exercise EVs. Still, 1 h post-exercise EVs failed to stimulate a pro-inflammatory program. In conclusion, the reported data provide a better understanding of the release of circulating EVs and their role as mediators of the inflammatory processes associated with exercise.

Mechanisms of function and clinical potential of exosomes in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) remains one of the most lethal and widespread malignancies in China. Exosomes, a subset of tiny extracellular vesicles manufactured by all cells and present in all body fluids, contribute to intercellular communication and have become a focus of the search for new therapeutic strategies for cancer. A number of global analyses of exosome-mediated functions and regulatory mechanism in malignant diseases have recently been reported. There is extensive evidence that exosomes can be used as diagnostic and prognostic markers for cancer. However, our understanding of their clinical value and mechanisms of action in ESCC is still limited and has not been systematically reviewed. Here, we review current research specifically focused on the functions and mechanisms of action of ESCC tumor-derived exosomes and non-ESCC-derived exosomes in ESCC progression and describe opportunities and challenges in the clinical translation of exosomes.

Aorta- and liver-generated TMAO enhances trained immunity for increased inflammation via ER stress/mitochondrial ROS/glycolysis pathways

We determined whether gut microbiota-produced trimethylamine (TMA) is oxidized into trimethylamine N-oxide (TMAO) in nonliver tissues and whether TMAO promotes inflammation via trained immunity (TI). We found that endoplasmic reticulum (ER) stress genes were coupregulated with MitoCarta genes in chronic kidney diseases (CKD); TMAO upregulated 190 genes in human aortic endothelial cells (HAECs); TMAO synthesis enzyme flavin-containing monooxygenase 3 (FMO3) was expressed in human and mouse aortas; TMAO transdifferentiated HAECs into innate immune cells; TMAO phosphorylated 12 kinases in cytosol via its receptor PERK and CREB, and integrated with PERK pathways; and PERK inhibitors suppressed TMAO-induced ICAM-1. TMAO upregulated 3 mitochondrial genes, downregulated inflammation inhibitor DARS2, and induced mitoROS, and mitoTEMPO inhibited TMAO-induced ICAM-1. β-Glucan priming, followed by TMAO restimulation, upregulated TNF-α by inducing metabolic reprogramming, and glycolysis inhibitor suppressed TMAO-induced ICAM-1. Our results have provided potentially novel insights regarding TMAO roles in inducing EC activation and innate immune transdifferentiation and inducing metabolic reprogramming and TI for enhanced vascular inflammation, and they have provided new therapeutic targets for treating cardiovascular diseases (CVD), CKD-promoted CVD, inflammation, transplantation, aging, and cancer.

The effects of home-based progressive resistance training in chronic kidney disease patients

INTRODUCTION

Faced with lockdowns, it was mandatory the development of supervised home-based RT protocols to keep patients with chronic kidney disease engaged in programs. Nonetheless, there is a lack of scientific literature regarding its effects on patients.

PURPOSE

To investigate the effects of a supervised home-based progressive resistance training program on functional performance, bone mineral density, renal function, endothelial health, inflammation, glycemic homeostasis, metabolism, redox balance, and the modulation of exerkines in patients with CKD in stage 2.

METHODS

Patients (n = 31) were randomized and allocated into the control group (CTL; n = 15; 58.07 ± 5.22 yrs) or resistance training group (RT; n = 16; 57.94 ± 2.74 yrs). RT group performed 22 weeks of supervised progressive home-based resistance exercises. Bone mineral density, anthropometric measurements, and functional performance were assessed. Venous blood samples were collected at baseline and after the intervention for the analysis of markers of renal function, endothelial health, inflammation, glycemic homeostasis, metabolism, and redox balance.

RESULTS

Twenty-two weeks of home-based RT were effective in improving (P < 0.05) functional performance, bone mineral density, uremic profile, ADMA, inflammatory markers, the Klotho-FGF23 axis, glycemic homeostasis markers, and exerkines. These improvements were accompanied by higher concentrations of exerkines and anti-inflammatory cytokines. RT group displayed a decrease in cases of osteopenia after the intervention (RT: 50 % vs. CTL: 86.7 %; X² = 4.763; P = 0.029).

CONCLUSION

Results provide new evidence that supervised home-based progressive RT may be a relevant intervention to attenuate the progression of CKD and improve functional capacity, bone mineral density, and the immunometabolic profile. These improvements are associated with positive modulation of several exerkines.

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.

Exercise Induced-Cytokines Response in Marathon Runners: Role of ACE I/D and BDKRB2 +9/-9 Polymorphisms

Renin-angiotensin system (RAS) and kallikrein-kinin system (KKS) have a different site of interaction and modulate vascular tone and inflammatory response as well on exercise adaptation, which is modulated by exercise-induced cytokines. The aim of the study was to evaluate the role of ACE I/D and BDKRB2 +9/−9 polymorphism on exercise-induced cytokine response. Seventy-four male marathon finishers, aged 30 to 55 years, participated in this study. Plasma levels of exercise-induced cytokines were determined 24 h before, immediately after, and 24 h and 72 h after the São Paulo International Marathon. Plasma concentrations of MCP-1, IL-6 and FGF-21 increased after marathon in all genotypes of BDKRB2. IL-10, FSTL and BDNF increased significantly after marathon in the genotypes with the presence of the −9 allele. FSTL and BDNF concentrations were higher in the −9/−9 genotype compared to the +9/+9 genotype before (p = 0.006) and after the race (p = 0.023), respectively. Apelin, IL-15, musclin and myostatin concentrations were significantly reduced after the race only in the presence of −9 allele. Marathon increased plasma concentrations of MCP1, IL-6, BDNF and FGF-21 in all genotypes of ACE I/D polymorphism. Plasma concentrations of IL-8 and MIP-1alpha before the race (p = 0.015 and p = 0.031, respectively), of MIP-1alpha and IL-10 after the race (p = 0.033 and p = 0.047, respectively) and VEGF 72 h after the race (p = 0.018) were lower in II homozygotes compared to runners with the presence of D allele. One day after the race we also observed lower levels of MIP-1alpha in runners with II homozygotes compared to DD homozygotes (p = 0.026). Before the marathon race myostatin concentrations were higher in DD compared to II genotypes (p = 0.009). Myostatin, musclin, IL-15, IL-6 and apelin levels decreased after race in genotypes with the presence of D allele. After the race ACE activity was negatively correlated with MCP1 (r = −56, p < 0.016) and positively correlated with IL-8, IL-10 and MIP1-alpha (r = 0.72, p < 0.0007, r = 0.72, p < 0.0007, r = 0.47, p < 0.048, respectively). The runners with the −9/−9 genotype have greater response in exercise-induced cytokines related to muscle repair and cardioprotection indicating that BDKRB2 participate on exercise adaptations and runners with DD genotype have greater inflammatory response as well as ACE activity was positively correlated with inflammatory mediators. DD homozygotes also had higher myostatin levels which modulates protein homeostasis.

Acute changes in free and extracellular vesicle-associated circulating miRNAs and myokine profile in professional sky-runners during the Gran Sasso d’Italia vertical run

The modification of gene expression profile, a first step in adaptation to exercise, leads to changes in the level of molecules associated with skeletal muscle activity and energy metabolism—such as myokines—as well as those involved in their transcriptional regulation, like microRNA. This study aimed to investigate the influence of strenuous exercise on circulating microRNAs and their possible association with myokine response. Pre-competition and post-competition plasma samples were collected from 14 male athletes participating in a vertical run (+1,000 m gain, 3,600 m length). Circulating total (t-miRNA) and extracellular vesicle-associated (EV-miRNA) miRNAs were extracted from the pooled plasma. Nanoparticle tracking analysis was performed to investigate pre- and post-competition EV concentration and size distribution. A panel of 179 miRNAs was assayed by qPCR and analyzed by Exiqon GenEx v6 normalized on the global mean. t-miRNA and EV-miRNAs whose level was ≥5-fold up- or down-regulated were validated for each single subject. Target prediction on MirWalk v3.0, Gene-Ontology, and pathway enrichment analysis on Panther v17.0 were performed to define the potential biological role of the identified miRNAs. A panel of 14 myokines was assayed in each sample by a multiplex immunoassay. In whole plasma, five miRNAs were upregulated and two were downregulated; in the EV fraction, five miRNAs were upregulated and three were downregulated. Nanoparticle tracking analysis revealed a similar EV size distribution in pre- and post-competition samples and a decreased concentration in post-competition samples related to pre-competition samples. Gene-Ontology and pathway enrichment analysis revealed that the identified t-miRNAs and EV-miRNAs were potentially involved in metabolism regulation in response to exercise. Correlation between fold-change of the post-competition relative to pre-competition plasma level of both t-miRNAs and EV-miRNAs and myokines further confirmed these results. This study provides an example of a systemic response to acute endurance exercise, in which circulating miRNAs play a pivotal role.

Contribution of organokines in the development of NAFLD/NASH associated hepatocellular carcinoma

Globally the incidence of hepatocellular carcinoma (HCC) is on an upsurge. Evidence is accumulating that liver disorders like nonalcoholic fatty liver disease (NAFLD) and its more progressive form nonalcoholic steatohepatitis (NASH) are associated with increased risk of developing HCC. NAFLD has a prevalence of about 25% and 50%-90% in obese population. With the growing burden of obesity epidemic worldwide, HCC presents a major healthcare burden. While cirrhosis is one of the major risk factors of HCC, available literature suggests that NAFLD/NASH associated HCC also develops in minimum or noncirrhotic livers. Therefore, there is an urgent need to understand the pathogenesis and risk factors associated with NAFLD and NASH related HCC that would help in early diagnosis and favorable prognosis of HCC secondary to NAFLD. Adipokines, hepatokines and myokines are factors secreted by adipocytes, hepatocytes and myocytes, respectively, playing essential roles in cellular homeostasis, energy balance and metabolism with autocrine, paracrine and endocrine effects. In this review, we endeavor to focus on the role of these organokines in the pathogenesis of NAFLD/NASH and its progression to HCC to augment the understanding of the factors stimulating hepatocytes to acquire a malignant phenotype. This shall aid in the development of novel therapeutic strategies and tools for early diagnosis of NAFLD/NASH and HCC.

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.

Neuroendocrine, Inflammatory, and Extracellular Vesicle Responses During the Navy Special Warfare Screener Selection Course

BACKGROUND

Military operational stress is known to increase adrenal hormones and inflammatory cytokines, while decreasing hormones associated with the anabolic milieu and neuroendocrine system. Less is known about the role of extracellular vesicles (EVs), a form of cell-to-cell communication, in military operational stress and their relationship to circulating hormones.

PURPOSE

To characterize the neuroendocrine, cytokine, and EV response to an intense, 24-h selection course known as the Naval Special Warfare (NSW) Screener and identify associations between EVs and cytokines.

METHODS

Blood samples were collected the morning of and following the NSW Screener in 29 men (18 - 26 years). Samples were analyzed for concentrations of cortisol, insulin-like growth factor I (IGF-I), neuropeptide-Y (NPY), brain-derived neurotrophic factor (BDNF), α-klotho, tumor necrosis factor- α (TNFα), and interleukins (IL) -1β, -6, and -10. EVs stained with markers associated with exosomes (CD63), microvesicles (VAMP3), and apoptotic bodies (THSD1) were characterized using imaging flow cytometry and vesicle flow cytometry.

RESULTS

The selection event induced significant changes in circulating BDNF (-43.2%), IGF-I (-24.56%), TNFα (+17.7%), IL-6 (+13.6%), accompanied by increases in intensities of THSD1⁺ and VAMP3⁺ EVs (all p<0.05). Higher concentrations of IL-1β and IL-10 were positively associated with THSD1⁺ EVs (p<0.05).

CONCLUSION

Military operational stress altered the EV profile. Surface markers associated with apoptotic bodies were positively correlated with an inflammatory response. Future studies should consider a multi-omics assessment of EV cargo to discern canonical pathways that may be mediated by EVs during military stress.

Precision Exercise Medicine: Sex Specific Differences in Immune and CNS Responses to Physical Activity

Physical activity is a powerful lifestyle factor capable of improving cognitive function, modifying the risk for dementia associated with neurodegeneration and possibly slowing neurodegenerative disease progression in both men and women. However, men and women show differences in the biological responses to physical activity and in the vulnerabilities to the onset, progression and outcome of neurodegenerative diseases, prompting the question of whether sex-specific regulatory mechanisms might differentially modulate the benefits of exercise on the brain. Mechanistic studies aimed to better understand how physical activity improves brain health and function suggest that the brain responds to physical exercise by overall reducing neuroinflammation and increasing neuroplasticity. Here, we review the emerging literature considering sex-specific differences in the immune system response to exercise as a potential mechanism by which physical activity affects the brain. Although the literature addressing sex differences in this light is limited, the initial findings suggest a potential influence of biological sex in the brain benefits of exercise, and lay out a scientific foundation to support very much needed studies investigating the potential effects of sex-differences on exercise neurobiology. Considering biological sex and sex-differences in the neurobiological hallmarks of exercise will help to enhance our understanding of the mechanisms by which physical activity benefits the brain and also improve the development of treatments and interventions for diseases of the central nervous system.

12 Weeks of Physical Exercise Attenuates Oxidative Stress, Improves Functional Tests Performance, and Reduces Fall Risk in Elderly Women Independently on Serum 25(OH)D Concentration

The study aimed to evaluate if the 25(OH)D concentration is related to physical training responses. Moreover, to determine the association between serum 25(OH)D concentration and older women's physical performance, oxidative stress markers, inflammation, and bone metabolism. 37 older women (age 72.9 ± 5.2 years) were assigned into two groups: supplemented (SG) and non-supplemented (NSG). Then, the participants from SG and NSG were randomly assigned into exercised and non-exercised groups: exercise sufficient vitamin D group (ESD; n = 10), exercise insufficient vitamin D group (EID; n = 9), control sufficient vitamin D group (CSD; n = 9), and control insufficient vitamin D group (CID; n = 9). To assess the study aims time up and go test (TUG), 6 min walk test (6MWT), fall risk test (FRT), blood osteocalcin (OC), parathormone (PTH), calcium (Ca²⁺), sulfhydryl groups (SH), malondialdehyde (MDA), and interleukin-6 (IL-6) were performed. The results showed that a higher 25(OH)D concentration was in line with better physical performance and bone metabolism as well as lower inflammation. After 12 weeks of training we noted an improvement in 6MWT (from 374.0 ± 17.3 to 415.0 ± 18.8; p = 0.001 and from 364.8 ± 32.8 to 419.4 ± 32.3; p = 0.001 for EID and ESD, respectively), TUG (from 7.9 ± 0.5 to 6.8 ± 0.8; p = 0.001 and from 7.3 ± 1.5 to 6.4 ± 0.9; p = 0.002, for EID and ESD, respectively), reduction of fall risk (from 2.8 ± 0.8 to 1.9 ± 0.4; p = 0.003 and from 2.1 ± 1.1 to 1.6 ± 0.5; p = 0.047, for EID and ESD, respectively) and increase in SH groups (from 0.53 ± 0.06 to 0.58 ± 0.08; p = 0.012 and from 0.54 ± 0.03 to 0.59 ± 0.04; p = 0.005, for EID and ESD, respectively), regardless of the baseline 25(OH)D concentration. A decrease in PTH and OC concentration was observed only in EID group (from 57.7 ± 15.7 to 49.4 ± 12.6; p = 0.013 for PTH and from 27.9 ± 17.2 to 18.0 ± 6.2; p = 0.004 for OC). To conclude, vitamin D concentration among older women is associated with physical performance, fall risk, inflammation, and bone metabolism markers. Moreover, 12 weeks of training improved physical performance and antioxidant protection, regardless of baseline vitamin D concentration.

The myokine Fibcd1 is an endogenous determinant of myofiber size and mitigates cancer-induced myofiber atrophy

Decline in skeletal muscle cell size (myofiber atrophy) is a key feature of cancer-induced wasting (cachexia). In particular, atrophy of the diaphragm, the major muscle responsible for breathing, is an important determinant of cancer-associated mortality. However, therapeutic options are limited. Here, we have used Drosophila transgenic screening to identify muscle-secreted factors (myokines) that act as paracrine regulators of myofiber growth. Subsequent testing in mouse myotubes revealed that mouse Fibcd1 is an evolutionary-conserved myokine that preserves myofiber size via ERK signaling. Local administration of recombinant Fibcd1 (rFibcd1) ameliorates cachexia-induced myofiber atrophy in the diaphragm of mice bearing patient-derived melanoma xenografts and LLC carcinomas. Moreover, rFibcd1 impedes cachexia-associated transcriptional changes in the diaphragm. Fibcd1-induced signaling appears to be muscle selective because rFibcd1 increases ERK activity in myotubes but not in several cancer cell lines tested. We propose that rFibcd1 may help reinstate myofiber size in the diaphragm of patients with cancer cachexia.

Exerkines in health, resilience and disease

The health benefits of exercise are well-recognized and are observed across multiple organ systems. These beneficial effects enhance overall resilience, healthspan and longevity. The molecular mechanisms that underlie the beneficial effects of exercise, however, remain poorly understood. Since the discovery in 2000 that muscle contraction releases IL-6, the number of exercise-associated signalling molecules that have been identified has multiplied. Exerkines are defined as signalling moieties released in response to acute and/or chronic exercise, which exert their effects through endocrine, paracrine and/or autocrine pathways. A multitude of organs, cells and tissues release these factors, including skeletal muscle (myokines), the heart (cardiokines), liver (hepatokines), white adipose tissue (adipokines), brown adipose tissue (baptokines) and neurons (neurokines). Exerkines have potential roles in improving cardiovascular, metabolic, immune and neurological health. As such, exerkines have potential for the treatment of cardiovascular disease, type 2 diabetes mellitus and obesity, and possibly in the facilitation of healthy ageing. This Review summarizes the importance and current state of exerkine research, prevailing challenges and future directions.

Cellular Chitchatting: Exploring the Role of Exosomes as Cardiovascular Risk Factors

Exosomes are small bi-lipid membranous vesicles (30–150 nm) containing different biological material such as proteins, lipids and nucleic acid. These small vesicles, inducing a cell to cell signaling pathway, are able to mediate multidirectional crosstalk to maintain homeostasis or modulate disease processes. With their various contents, exosomes sort and transfer specific information from their origin to a recipient cell, from a tissue or organ in the close proximity or at distance, generating an intra-inter tissue or organ communication. In the last decade exosomes have been identified in multiple organs and fluids under different pathological conditions. In particular, while the content and the abundance of exosome is now a diagnostic marker for cardiovascular diseases, their role in context-specific physiological and pathophysiological conditions in the cardiovascular system remains largely unknown. We summarize here the current knowledge on the role of exosomes as mediators of cardiovascular diseases in several pathophysiological conditions such as atherosclerosis and diabetes. In addition, we describe evidence of intercellular connection among multiple cell type (cardiac, vasculature, immune cells) as well as the challenge of their in vivo analysis.

AMP-activated protein kinase activation in skeletal muscle modulates exercise-induced uncoupled protein 1 expression in brown adipocyte in mouse model

Abstract

Aerobic exercise is an effective intervention in preventing obesity and is also an important factor associated with thermogenesis. There is an increasing interest in the factors and mechanisms induced by aerobic exercise that can influence the metabolism and thermogenic activity in an individual. Recent studies suggest that exercise induced circulating factors (known as ‘exerkines’), which are able to modulate activation of brown adipose tissue (BAT) and browning of white adipose tissue. However, the underlying molecular mechanisms associated with the effect of exercise‐induced peripheral factors on BAT activation remain poorly understood. Furthermore, the role of exercise training in BAT activation is still debatable. Hence, the purpose of our study is to assess whether exercise training affects the expression of uncoupled protein 1 (UCP1) in brown adipocytes via release of different blood factors. Four weeks of exercise training significantly decreased the body weight gain and fat mass gain. Furthermore, trained mice exhibit higher levels of energy expenditure and UCP1 expression than untrained mice. Surprisingly, treatment with serum from exercise‐trained mice increased the expression of UCP1 in differentiated brown adipocytes. To gain a better understanding of these mechanisms, we analysed the conditioned media obtained after treating the C2C12 myotubes with an AMP‐activated protein kinase (AMPK) activator (AICAR; 5‐aminoimidazole‐4‐carboxamide ribonucleotide), which leads to an increased expression of UCP1 when added to brown adipocytes. Our observations suggest the possibility of aerobic exercise‐induced BAT activation via activation of AMPK in skeletal muscles.

Key points

Exercise promotes thermogenesis by activating uncoupling protein 1 (UCP1), which leads to a decrease in the body weight gain and body fat content. However, little is known about the role of exerkines in modulating UCP1 expression and subsequent brown adipose tissue (BAT) activation.

Four weeks of voluntary wheel‐running exercise reduces body weight and fat content.

Exercise induces the increase in AMP‐activated protein kinase (AMPK) and slow‐type muscle fibre marker genes in skeletal muscles and promotes UCP1 expression in white and brown adipose tissues.

Incubation of brown adipocytes with serum isolated from exercise‐trained mice significantly increased their UCP1 gene and protein levels; moreover, conditioned media of AMPK‐activator‐treated C2C12 myotubes induces increased UCP1 expression in brown adipocytes.

These results show that aerobic exercise‐induced skeletal muscle AMPK has a significant effect on UCP1 expression in BAT.

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.

Single bout of exercise triggers the increase of vitamin D blood concentration in adolescent trained boys: a pilot study

Vitamin D is necessary for musculoskeletal health, however, the supplementation of vitamin D above the sufficiency level does not bring additional bone mass density (BMD), unlike physical exercise which enhances the bone formatting process. Regular physical activity has been shown to upregulate VDR expression in muscles and to increase circulating vitamin D. Here we investigate whether a single bout of exercise might change 25(OH)D₃ blood concentration and how it affects metabolic response to exercise. Twenty-six boys, 13.8 years old (SD ± 0.7) soccer players, participated in the study. The participants performed one of two types of exercise: the first group performed the VO₂max test until exhaustion, and the second performed three times the repeated 30 s Wingate Anaerobic Test (WAnT). Blood was collected before, 15 min and one hour after the exercise. The concentration of 25(OH)D₃, parathyroid hormone (PTH), interleukin-6 (IL-6), lactate, non-esterified fatty acids (NEFA) and glycerol were determined. 25(OH)D₃ concentration significantly increased after the exercise in all boys. The most prominent changes in 25(OH)D₃, observed after WAnT, were associated with the rise of PTH. The dimensions of response to the exercises observed through the changes in the concentration of 25(OH)D₃, PTH, NEFA and glycerol were associated with the significant increases of IL-6 level. A single bout of exercise may increase the serum’s 25(OH)D₃ concentration in young trained boys. The intensive interval exercise brings a more potent stimulus to vitamin D fluctuations in young organisms. Our results support the hypothesis that muscles may both store and release 25(OH)D₃.

Potential Mechanism Underlying Exercise Upregulated Circulating Blood Exosome miR-215-5p to Prevent Necroptosis of Neuronal Cells and a Model for Early Diagnosis of Alzheimer's Disease

Exercise is crucial for preventing Alzheimer's disease (AD), although the exact underlying mechanism remains unclear. The construction of an accurate AD risk prediction model is beneficial as it can provide a theoretical basis for preventive exercise prescription. In recent years, necroptosis has been confirmed as an important manifestation of AD, and exercise is known to inhibit necroptosis of neuronal cells. In this study, we extracted 67 necroptosis-related genes and 32 necroptosis-related lncRNAs and screened for key predictive AD risk genes through a random forest analysis. Based on the neural network Prediction model, we constructed a new logistic regression-based AD risk prediction model in order to provide a visual basis for the formulation of exercise prescription. The prediction model had an area under the curve (AUC) value of 0.979, indicative of strong predictive power and a robust clinical application prospect. In the exercise group, the expression of exosomal miR-215-5p was found to be upregulated; miR-215-5p could potentially inhibit the expressions of IDH1, BCL2L11, and SIRT1. The single-cell SCENIC assay was used to identify key transcriptional regulators in skeletal muscle. Among them, CEBPB and GATA6 were identified as putative transcriptional regulators of miR-215. After "skeletal muscle removal of load," the expressions of CEBPB and GATA6 increased substantially, which in turn led to the elevation of miR-215 expression, thereby suggesting a putative mechanism for negative feedback regulation of exosomal homeostasis.

Exploring New Kingdoms: The Role of Extracellular Vesicles in Oxi-Inflamm-Aging Related to Cardiorenal Syndrome

The incidence of age associated chronic diseases has increased in recent years. Although several diverse causes produce these phenomena, abundant evidence shows that oxidative stress plays a central role. In recent years, numerous studies have focused on elucidating the role of oxidative stress in the development and progression of both aging and chronic diseases, opening the door to the discovery of new underlying mechanisms and signaling pathways. Among them, senolytics and senomorphics, and extracellular vesicles offer new therapeutic strategies to slow the development of aging and its associated chronic diseases by decreasing oxidative stress. In this review, we aim to discuss the role of extracellular vesicles in human cardiorenal syndrome development and their possible role as biomarkers, targets, or vehicles of drugs to treat this syndrome.

Novel Knowledge-Based Transcriptomic Profiling of Lipid Lysophosphatidylinositol-Induced Endothelial Cell Activation

To determine whether pro-inflammatory lipid lysophosphatidylinositols (LPIs) upregulate the expressions of membrane proteins for adhesion/signaling and secretory proteins in human aortic endothelial cell (HAEC) activation, we developed an EC biology knowledge-based transcriptomic formula to profile RNA-Seq data panoramically. We made the following primary findings: first, G protein-coupled receptor 55 (GPR55), the LPI receptor, is expressed in the endothelium of both human and mouse aortas, and is significantly upregulated in hyperlipidemia; second, LPIs upregulate 43 clusters of differentiation (CD) in HAECs, promoting EC activation, innate immune trans-differentiation, and immune/inflammatory responses; 72.1% of LPI-upregulated CDs are not induced in influenza virus-, MERS-CoV virus- and herpes virus-infected human endothelial cells, which hinted the specificity of LPIs in HAEC activation; third, LPIs upregulate six types of 640 secretomic genes (SGs), namely, 216 canonical SGs, 60 caspase-1-gasdermin D (GSDMD) SGs, 117 caspase-4/11-GSDMD SGs, 40 exosome SGs, 179 Human Protein Atlas (HPA)-cytokines, and 28 HPA-chemokines, which make HAECs a large secretory organ for inflammation/immune responses and other functions; fourth, LPIs activate transcriptomic remodeling by upregulating 172 transcription factors (TFs), namely, pro-inflammatory factors NR4A3, FOS, KLF3, and HIF1A; fifth, LPIs upregulate 152 nuclear DNA-encoded mitochondrial (mitoCarta) genes, which alter mitochondrial mechanisms and functions, such as mitochondrial organization, respiration, translation, and transport; sixth, LPIs activate reactive oxygen species (ROS) mechanism by upregulating 18 ROS regulators; finally, utilizing the Cytoscape software, we found that three mechanisms, namely, LPI-upregulated TFs, mitoCarta genes, and ROS regulators, are integrated to promote HAEC activation. Our results provide novel insights into aortic EC activation, formulate an EC biology knowledge-based transcriptomic profile strategy, and identify new targets for the development of therapeutics for cardiovascular diseases, inflammatory conditions, immune diseases, organ transplantation, aging, and cancers.

Molecular Pathogenesis and the Possible Role of Mitochondrial Heteroplasmy in Thoracic Aortic Aneurysm

Thoracic aortic aneurysm (TAA) is a life-threatening condition associated with high mortality, in which the aortic wall is deformed due to congenital or age-associated pathological changes. The mechanisms of TAA development remain to be studied in detail, and are the subject of active research. In this review, we describe the morphological changes of the aortic wall in TAA. We outline the genetic disorders associated with aortic enlargement and discuss the potential role of mitochondrial pathology, in particular mitochondrial DNA heteroplasmy, in the disease pathogenesis.

Nordic Walking Rather Than High Intensity Interval Training Reduced Myostatin Concentration More Effectively in Elderly Subjects and the Range of This Drop Was Modified by Metabolites of Vitamin D

The COVID-19 pandemic and subsequent self-isolation exacerbated the problem of insufficient amounts of physical activity and its consequences. At the same time, this revealed the advantage of vitamin D. Thus, there was a need to verify the effects of those forms of training that can be performed independently. In this study, we examined the effects of Nordic walking (NW) and high intensity interval training (HIIT) with regard to the impact of the metabolite vitamin D. We assigned 32 overweight adults (age = 61 ± 12 years) to one of two training groups: NW = 18 and HIIT = 14. Body composition assessment and blood sample collection were conducted before starting the training programs and a day after their completion. NW training induced a significant decrease in myostatin (p = 0.05) concentration; however, the range was dependent on the baseline concentrations of vitamin D metabolites. This drop was accompanied by a significant negative correlation with the decorin concentration. Unexpectedly, NW caused a decrement in both forms of osteocalcin: undercarboxylated (Glu-OC) and carboxylated-type (Gla-OC). The scope of Glu-OC changes was dependent on a baseline concentration of 25(OH)D₂ (r = −0.60, p = 0.01). In contrast, the HIIT protocol did not induce any changes. Overall results revealed that NW diminished the myostatin concentration and that this effect is more pronounced among adults with a sufficient concentration of vitamin D metabolites.

Impact of the Main Cardiovascular Risk Factors on Plasma Extracellular Vesicles and Their Influence on the Heart's Vulnerability to Ischemia-Reperfusion Injury

The majority of cardiovascular deaths are associated with acute coronary syndrome, especially ST-elevation myocardial infarction. Therapeutic reperfusion alone can contribute up to 40 percent of total infarct size following coronary artery occlusion, which is called ischemia-reperfusion injury (IRI). Its size depends on many factors, including the main risk factors of cardiovascular mortality, such as age, sex, systolic blood pressure, smoking, and total cholesterol level as well as obesity, diabetes, and physical effort. Extracellular vesicles (EVs) are membrane-coated particles released by every type of cell, which can carry content that affects the functioning of other tissues. Their role is essential in the communication between healthy and dysfunctional cells. In this article, data on the variability of the content of EVs in patients with the most prevalent cardiovascular risk factors is presented, and their influence on IRI is discussed.