Improvement of microvascular endothelial dysfunction induced by exercise and diet is associated with microRNA-126 in obese adolescents

A 5-Week Guided Active Play Program Modulates Skin Microvascular Reactivity in Healthy Children

PURPOSE

Children's poor levels of physical activity (PA) participation and early-onset vascular aging are identified as global health challenges. Children's guided activity play (GAP)-based PA programs have emerged as effective strategies to improve cardiovascular risk factors and health-related fitness. This study proposes to investigate whether GAP improves children's cutaneous microvascular reactivity and health-related fitness.

METHODS

Children's (n = 18; 9.8 [1.5] y) PA during a 5-week (4 d/wk; 1 h/d) GAP program was assessed (accelerometry) with preassessments and postassessments for anthropometric, musculoskeletal fitness, blood pressure, estimated aerobic power, and cutaneous microvascular reactivity.

RESULTS

PA averaged 556 (132) kcal·week-1 at 34.7% (7.5%) time at moderate to vigorous intensity. Resting heart rate (-9.5%) and diastolic blood pressure (-7.8%) were reduced without changes in health-related fitness indices. Cutaneous microvascular reactivity to sodium nitroprusside iontophoresis increased the average perfusion (+36.8%), average cutaneous vascular conductance (+30%), the area under the curve (+28.8%), and a faster rise phase (+40%) of perfusion (quadratic modeling; P ≤ .05). Chi-square and crosstabulation analysis revealed significant association between children's PA levels and sodium nitroprusside average perfusion levels, where children with PA levels ≥205.1 kcal.55 minute-1 were overrepresented in the medium/high levels of sodium nitroprusside perfusion.

CONCLUSION

A 5-week GAP modified the microvascular reactivity in children without changes in body mass, musculoskeletal fitness, or estimated aerobic power.

The Role and Potential Mechanisms of Rehabilitation Exercise Improving Cardiac Remodeling

Rehabilitation exercise is a crucial non-pharmacological intervention for the secondary prevention and treatment of cardiovascular diseases, effectively ameliorating cardiac remodeling in patients. Exercise training can mitigate cardiomyocyte apoptosis, reduce extracellular matrix deposition and fibrosis, promote angiogenesis, and regulate inflammatory response to improve cardiac remodeling. This article presents a comprehensive review of recent research progress, summarizing the pivotal role and underlying mechanism of rehabilitation exercise in improving cardiac remodeling and providing valuable insights for devising effective rehabilitation treatment programs. Graphical Abstract.

A nutraceutical with Citrus bergamia and Cynara cardunculus improves endothelial function in adults with non-alcoholic fatty liver disease

OBJECTIVE

Polyphenol intake may prevent hepatic steatosis and cardiovascular disease by potentially improving endothelial function. The purposes of this study are to investigate the association between fatty liver disease and endothelial dysfunction and to test the effects of a nutraceutical containing extracts made from Citrus bergamia and Cynara cardunculus on peripheral vascular endothelial function in adults with liver steatosis.

METHODS

We analyzed data from 32 individuals with hepatic steatosis and endothelial dysfunction (reactive hyperemia index ≤ 1.67). Sixteen subjects took 1 capsule/d (300 mg/d) containing Cynara cardunculus extract and bergamot polyphenol fraction, while the other 16 subjects matched for age, sex, and body mass index took 1 capsule/d of placebo (maltodextrin) for 12 wk. All anthropometric parameters were assessed at baseline and after 12 wk as were lipids, glucose, and reactive hyperemia index using an EndoPAT 2000.

RESULTS

The mean age was 52 ± 9 y. The mean reactive hyperemia index was 1.15 ± 0.4. After 12 wk, we found a greater increase in reactive hyperemia index in the participants taking the nutraceutical rather than placebo (0.58 ± 0.5 versus 0.13 ± 0.5; P = 0.02, respectively). The stepwise multivariable analysis confirmed a positive association between reactive hyperemia index change and the nutraceutical treatment (B = 0.38; P = 0.025) and negative association with reactive hyperemia index values at baseline (B = -0.81; P < 0.001). No association was found between the reduction in the amount of intrahepatic fat and the improvement of endothelial function (B = 0.002; P = 0.56).

CONCLUSIONS

A nutraceutical containing bergamot and artichoke extracts improves peripheral vascular endothelial function in adults with hepatic steatosis and early phase of atherosclerosis.

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.

Association between circulating micro-ribonucleic acids and metabolic syndrome in older adults from a population-based study

BACKGROUND AND AIMS

Aging is a major factor in development of chronic non-communicable diseases (NCD). Epigenetic causes are risk factors in NCD development since studies indicate that the expression of micro-ribonucleic acids (miRs) is altered under different clinical conditions. This study aimed to analyze the expression profile of circulating miRs and investigate their association with biomarkers of cardiometabolic risk in older adults living in São Paulo municipality, Brazil.

METHODS

A cross-sectional study was conducted based on the analysis of data from 200 older adults, with a mean age of 69.1 (0.5) years old participating in the ISA-Nutrition. The expression profiles of 21 plasma miRs related to glycemic and lipid metabolism, adiposity, and inflammation were evaluated in relation to cardiometabolic risk. Individuals were distributed into groups according to diagnosis of metabolic syndrome (MetS). The Stata Somersd module was used to calculate confidence intervals for Kendall's tau-a to estimate the correlations among variables.

RESULTS

Differences in the plasma expression were observed in two of the 21 miRs evaluated according to the MetS presence in participants. Individuals with MetS showed higher expression of miR-30a and miR-122 than individuals without MetS.

CONCLUSIONS

Considering that miR-30, and miR-122 were altered due to MetS, these miRs may be potential biomarkers for MetS in older adults.

Extracellular microRNAs in Relation to Weight Loss-A Systematic Review and Meta-Analysis

Obesity is an important risk factor for cardiovascular disease and type 2 diabetes mellitus. Even a modest weight loss of 5-15% improves metabolic health, but circulating markers to indicate weight loss efficiency are lacking. MicroRNAs, small non-coding post-transcriptional regulators of gene expression, are secreted from tissues into the circulation and may be potential biomarkers for metabolic health. However, it is not known which specific microRNA species are reproducibly changed in levels by weight loss. In this study, we performed a systematic review and meta-analysis to investigate the microRNAs associated with weight loss by comparing baseline to follow-up levels following intervention-driven weight loss. This systematic review was performed according to the PRISMA guidelines with searches in PubMed and SCOPUS. The primary search resulted in a total of 697 articles, which were screened according to the prior established inclusion and exclusion criteria. Following the screening of articles, the review was based on the inclusion of 27 full-text articles, which were evaluated for quality and the risk of bias. We performed systematic data extraction, whereafter the relative values for miRNAs were calculated. A meta-analysis was performed for the miRNA species investigated in three or more studies: miR-26a, miR-126, and miR-223 were overall significantly increased following weight loss, while miR-142 was significantly decreased after weight loss. miR-221, miR-140, miR-122, and miR-146 were not significantly changed by intervention-driven weight loss. These results indicate that few miRNAs are significantly changed during weight loss.

Novel use of structural equation modelling to examine diet and metabolic traits associated with microvascular endothelial dysfunction in middle-aged Chinese males: a cross-sectional study

BACKGROUND

The present study aims to use structural equation modelling (SEM) with multiple regression pathways to examine direct and indirect links from diet and metabolic traits to microvascular endothelial dysfunction (ED) among middle-aged Chinese males.

METHODS

The study was conducted in middle-aged Chinese males, who underwent a health check-up between 2018 and 2019. Data on lifestyle behaviour factors (physical activity, diet pattern, sleep quality and diet data underwent factor analysis in advance) and metabolic risk factors referring to metabolic traits were introduced into the SEM to examine inter-relationship among these factors and their association with ED, as evaluated by the reactive hyperaemia index (RHI).

RESULTS

Both exploratory factor analysis and confirmatory factor analysis identified two major dietary patterns: 'prudent pattern' and 'western pattern'. The univariate test suggested that only triglycerides (TGs) and prudent dietary pattern were directly associated with RHI. Furthermore, prudent dietary pattern had an indirect association with RHI via TG (prudent diet→TG: β=-0.15, p<0.05; TG→RHI: β=-0.17, p<0.001). As to confirming the hypothesised association between variables apart, physical activity frequency was correlated to the decrease in TG (β=-0.29, p<0.001), but had no direct correlation to RHI.

CONCLUSION

The network of direct and indirect associations among diet pattern and cardiometabolic risk factors with RHI measured ED among middle-aged males. The most significant modifiable factors identified were TG and prudent diet pattern, which needs to be targeted as preventive strategies for early microvascular impairment.

Preventative interventions that target cardiovascular dysfunction in children and young people: a systematic review of their effectiveness and an investigation of sexual dimorphism

Given that cardiovascular diseases remain a primary cause of mortality and morbidity, there is a need to consider preventative strategies to improve vascular function from early in life. The aims of this study were therefore to investigate which interventions may improve endothelial function, intima media thickness and arterial stiffness in children and young people and to assess whether these interventions differ in boys and girls. A systematic literature search of Science Direct, Pubmed, Google Scholar and the Cochrane Library by two independent reviewers was performed to source articles. Inclusion criteria were any studies including any child ≤18 years of age receiving an intervention, which measured vascular function other than blood pressure. Exclusion criteria were studies assessing children with chronic medical conditions. A total of 72 studies were identified, which met the inclusion criteria. A measurable change in outcome was more likely to be reported in studies investigating endothelial function (p = 0.03). Interventions which improved vascular function included physical activity and dietary programmes. Under 10% of studies considered sex differences. In conclusion, school-based physical activity interventions are most likely to result in improvements in vascular function. Endothelial function may be the first variable of vascular function to change secondary to an intervention. Standardisation of reporting of differences between the sexes is essential to be able to ensure interventions are equally effective for boys and girls.

Therapeutic Potentials of MicroRNA-126 in Cerebral Ischemia

Stroke is a leading cause of death and disability worldwide. It is among the most common neurological disorders with an 8-10% lifetime risk. Ischemic stroke accounts for about 85% of all strokes and damages the brain tissue via various damaging mechanisms. Following cerebral ischemia, the disrupted blood-brain barrier (BBB) leads to cerebral edema formation caused by activation of oxidative stress, inflammation, and apoptosis, targeting primarily endothelial cells. Activation of the protective mechanisms might favor fewer damages to the neural tissue. MicroRNA (miR)-126 is an endothelial cell-specific miR involved in angiogenesis. MiR-126 orchestrates endothelial progenitor cell functions under hypoxic conditions and could inhibit ischemia-induced oxidative stress and inflammation. It alleviates the BBB disruption by preventing an augment in matrix metalloproteinase level and halting the decrease in the junctional proteins, including zonula occludens-1 (ZO-1), claudin-5, and occludin levels. Moreover, miR-126 enhances post-stroke angiogenesis and neurogenesis. This work provides a therapeutic perspective for miR-126 as a new approach to treating cerebral ischemia.

The effect of 4 weeks of high-intensity interval training and 2 weeks of detraining on cardiovascular disease risk factors in male adolescents

NEW FINDINGS

What is the central question of this study? What is the effect of 4 weeks of high-intensity interval training (HIIT) and 2 weeks of detraining on vascular function and traditional cardiovascular disease (CVD) risk factors in male adolescents? What is the main finding and its importance? Four weeks of HIIT improved macrovascular function in adolescents. However, this training period did not measurably change microvascular function, body composition or blood biomarkers. Following 2 weeks of detraining, the improvement in flow-mediated dilatation (FMD) was lost. This highlights the importance of the continuation of regular exercise for the primary prevention of CVD.

ABSTRACT

High-intensity interval training (HIIT) represents an effective method to improve cardiometabolic health in adolescents. This study aimed to investigate the effect of 4 weeks of HIIT followed by 2 weeks of detraining on vascular function and traditional cardiovascular disease (CVD) risk factors in adolescent boys. Nineteen male adolescents (13.3 ± 0.5 years) were randomly allocated to either a training (TRAIN, n = 10) or control (CON, n = 9) group. Participants in TRAIN completed 4 weeks of HIIT running with three sessions per week. Macro- (flow-mediated dilatation, FMD) and microvascular (peak reactive hyperaemia, PRH) function, body composition (fat mass, fat free mass, body fat percentage) and blood biomarkers (glucose, insulin, total cholesterol, high- and low-density lipoprotein, triacylglycerol) were assessed pre-, 48 h post- and 2 weeks post-training for TRAIN and at equivalent time points for CON. Following training, FMD was significantly greater in TRAIN compared to CON (9.88 ± 2.40% and 8.64 ± 2.70%, respectively; P = 0.036) but this difference was lost 2 weeks after training cessation (8.22 ± 2.47% and 8.61 ± 1.99%, respectively; P = 0.062). No differences were detected between groups for PRH (P = 0.821), body composition (all P > 0.14) or blood biomarkers (all P > 0.18). In conclusion, 4 weeks of HIIT improved macrovascular function; however, this training period did not measurably change microvascular function, body composition or blood biomarkers. The reversal of the FMD improvement 2 weeks post-training highlights the importance of the continuation of regular exercise for the primary prevention of CVD.

A review of the signaling pathways of aerobic and anaerobic exercise on atherosclerosis

Atherosclerosis (AS), a chronic inflammatory vascular disease with lipid metabolism abnormalities, is one of the major pathological bases of coronary heart disease. As people's lifestyles and diets change, the incidence of AS increases yearly. Physical activity and exercise training have recently been identified as effective strategies for lowering cardiovascular disease (CVD) risk. However, the best exercise mode to ameliorate the risk factors related to AS is not clear. The effect of exercise on AS is affected by the type of exercise, intensity, and duration. In particular, aerobic and anaerobic exercise are the two most widely discussed types of exercise. During exercise, the cardiovascular system undergoes physiological changes via various signaling pathways. The review aims to summarize signaling pathways related to AS in two different exercise types and provide new ideas for the prevention and treatment of AS in clinical practice.

Endothelial Peripheral Arterial Tonometry (Endo-PAT 2000) use in paediatric patients: a systematic review

OBJECTIVES

Endo Peripheral Artery Tonometry (EndoPAT-2000) is a non-invasive technology for measuring endothelial dysfunction (ED). The reactive hyperaemia index (RHI) is resulted and is low when ED is present. We aim to synthesise the literature on paediatric ED that used Endo-PAT analysis.

DESIGN

A comprehensive systematic review was conducted from January 2015 to March 2021. The databases included Cochrane, MEDLINE EBSCO, EMBASE (Ovid), PUBMED and CINAHL EBSCO. Exclusion criteria were: (1) If a study used a different device, for example, (2) If the study had no results. Inclusion criteria were: (1) Published in the English, (2) more than 50% of study subjects were in the paediatric age range, (3) data relevant to paediatric age range children could be extrapolated from all data, where not all study subjects were children.

RESULTS

Following the removal of duplicates, 156 articles were initially identified. Following exclusion, 50 articles were included for review. We have subdivided these papers into different systems for ease of reference and have reported our findings in six tables: patients with type 1/2 diabetes, obesity, cardiovascular, respiratory, psychiatric conditions and miscellaneous diseases. For each, the study design, population, control group (if available), RHI results and conclusions were reported.

CONCLUSIONS

A number of papers using Endo-PAT for children with various chronic diseases have evidence of ED. However, in many cases, there has only been a single cohort study using Endo-PAT. Further studies are required to validate these findings and to help characterise the cardiovascular risk profile of children with chronic disease. Further studies are also required that will characterise more completely the cardiovascular risk profile of these children.Consensus on other vascular risk markers that could be included in future studies is ideal and if accomplished, this would facilitate meta-analyses of studies of relatively rare conditions.

Walking Training Increases microRNA-126 Expression and Muscle Capillarization in Patients with Peripheral Artery Disease

Patients with peripheral artery disease (PAD) have reduced muscle capillary density. Walking training (WT) is recommended for PAD patients. The goal of the study was to verify whether WT promotes angiogenesis in PAD-affected muscle and to investigate the possible role of miRNA-126 and the vascular endothelium growth factor (VEGF) angiogenic pathways on this adaptation. Thirty-two men with PAD were randomly allocated to two groups: WT (n = 16, 2 sessions/week) and control (CO, n = 16). Maximal treadmill tests and gastrocnemius biopsies were performed at baseline and after 12 weeks. Histological and molecular analyses were performed by blinded researchers. Maximal walking capacity increased by 65% with WT. WT increased the gastrocnemius capillary-fiber ratio (WT = 109 ± 13 vs. 164 ± 21 and CO = 100 ± 8 vs. 106 ± 6%, p < 0.001). Muscular expression of miRNA-126 and VEGF increased with WT (WT = 101 ± 13 vs. 130 ± 5 and CO = 100 ± 14 vs. 77 ± 20%, p < 0.001; WT = 103 ± 28 vs. 153 ± 59 and CO = 100 ± 36 vs. 84 ± 41%, p = 0.001, respectively), while expression of PI3KR2 decreased (WT = 97 ± 23 vs. 75 ± 21 and CO = 100 ± 29 vs. 105 ± 39%, p = 0.021). WT promoted angiogenesis in the muscle affected by PAD, and miRNA-126 may have a role in this adaptation by inhibiting PI3KR2, enabling the progression of the VEGF signaling pathway.

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.

New developments in translational microcirculatory research

Microvascular disease plays a critical role in systemic end-organ dysfunction, and treatment of microvascular pathologies may greatly reduce cardiovascular morbidity and mortality. The Call for Papers collection: New Developments in Translational Microcirculatory Research highlights key advances in our understanding of the role of microvessels in the development of chronic diseases as well as therapeutic strategies to enhance microvascular function. This Mini Review provides a concise summary of these advances and draws from other relevant research to provide the most up-to-date information on the influence of cutaneous, cerebrovascular, coronary, and peripheral microcirculation on the pathophysiology of obesity, hypertension, cardiovascular aging, peripheral artery disease, and cognitive impairment. In addition to these disease- and location-dependent research articles, this Call for Papers includes state-of-the-art reviews on coronary endothelial function and assessment of microvascular health in different organ systems, with an additional focus on establishing rigor and new advances in clinical trial design. These articles, combined with original research evaluating cellular, exosomal, pharmaceutical, exercise, heat, and dietary interventional therapies, establish the groundwork for translating microcirculatory research from bench to bedside. Although numerous studies in this collection are focused on human microcirculation, most used robust preclinical models to probe mechanisms of pathophysiology and interventional benefits. Future work focused on translating these findings to humans are necessary for finding clinical strategies to prevent and treat microvascular dysfunction.

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.

Molecular characterization of insulin receptor (IR) in oriental fruit moth, Grapholita molesta (Lepidoptera: Tortricidae), and elucidation of its regulatory roles in glucolipid homeostasis and metamorphosis through interaction with miR-982490

As an intermediate molecule in the Insulin/Insulin-like growth factor signalling pathway (IIS), the insulin receptor (IR) plays vital roles linking nutritional signals to the downstream regulation of metabolic homeostasis, development, metamorphosis, reproduction and stress responses. In the present study, we describe the molecular characteristics of IR in the cosmopolitan fruit boring pest, Grapholita molesta, and its predicted posttranscription regulator miR-982490, and elucidate its regulatory roles in glucolipid homeostasis and metamorphosis. Phylogenetic and domain analyses indicate that lepidopteran IRs normally cluster within families, and that four main domains are conserved in GmIR and those of other Lepidoptera. Bio-informatic prediction, synchronic expression profile evaluation and dual luciferase reporter assays indicated negative regulation of GmIR by miR-982490. Injection of miR-982490 agomir into fifth instar larvae yielded effects similar to dsGmIR injection, resulting in enhanced levels of trehalose and triglyceride in haemolymph, and reduced pupation success and pupal weight, both of which could be rescued by co-injection of dsGmIR and miR-982490 antagomir. We infer that GmIR regulates glucolipid homeostasis and affects G. molesta metamorphosis via interactions with its posttranscriptional regulator miR-982490. This study expands our understanding of the regulatory network of IIS in insect nutritional homeostasis and development.

MicroRNAs as the promising markers of comorbidities in childhood obesity-A systematic review

INTRODUCTION

Rising child obesity rate creates a need for tools quantifying changes in children suffering from obesity, for purposes of detection or prevention of comorbidities. A candidate for such a role seems to be microRNAs, which in vivo serve as the suppressing factors in gene expression.

OBJECTIVES

This study aimed at reviewing recent discoveries in this field and concluding directions of research or application of studied molecules.

METHODS

Repeated browsing of databases and screening of results, led to final approval of 16 articles. Filtered studies examined differences in microRNA expression between subjects with obesity and children suffering from its comorbidities.

RESULTS

Studies concerning endothelial dysfunction identified molecules miR-320a and miR-630 as a possible diagnosis and treatment option. Search for the alternative markers in diagnosis of non-alcoholic fatty liver disease suggested value of molecules: miR-199a-5p and miR-122. miR-486, miR-146b, and miR-15b may serve in grading the development of type 2 diabetes in children, although further research raised doubts. Panel of molecules was indicated as useful in early detection of metabolic syndrome and insulin resistance associated alterations. No valid link between studied microRNAs and atherosclerosis was found.

CONCLUSIONS

MicroRNAs seem to be promising prognostic markers for diagnosis of endothelial dysfunction, non-alcoholic fatty liver disease, type 2 diabetes, metabolic syndrome and insulin resistance in children.

Noncoding RNAs in age-related cardiovascular diseases

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality in the adult population worldwide and represent a severe economic burden and public health concern. The majority of human genes do not code for proteins. However, noncoding transcripts play important roles in ageing that significantly increases the risk for CVDs. Noncoding RNAs (ncRNAs) are critical regulators of multiple biological processes related to ageing such as oxidative stress, mitochondrial dysfunction and chronic inflammation. NcRNAs are also involved in pathophysiological developments within the cardiovascular system including arrhythmias, cardiac hypertrophy, fibrosis, myocardial infarction and heart failure. In this review article, we cover the roles of ncRNAs in cardiovascular ageing and disease as well as their potential therapeutic applications in CVDs.

Perspectives and challenges of epigenetic determinants of childhood obesity: A systematic review

The tremendous increase in childhood obesity prevalence over the last few decades cannot merely be explained by genetics and evolutionary changes in the genome, implying that gene-environment interactions, such as epigenetic modifications, likely play a major role. This systematic review aims to summarize the evidence of the association between epigenetics and childhood obesity. A literature search was performed via PubMed and Scopus engines using a combination of terms related to epigenetics and pediatric obesity. Articles studying the association between epigenetic mechanisms (including DNA methylation and hydroxymethylation, non-coding RNAs, and chromatin and histones modification) and obesity and/or overweight (or any related anthropometric parameters) in children (0-18 years) were included. The risk of bias was assessed with a modified Newcastle-Ottawa scale for non-randomized studies. One hundred twenty-one studies explored epigenetic changes related to childhood obesity. DNA methylation was the most widely investigated mechanism (N = 101 studies), followed by non-coding RNAs (N = 19 studies) with evidence suggestive of an association with childhood obesity for DNA methylation of specific genes and microRNAs (miRNAs). One study, focusing on histones modification, was identified. Heterogeneity of findings may have hindered more insights into the epigenetic changes related to childhood obesity. Gaps and challenges that future research should face are herein described.

Epigenetic effects following acute and chronic exercise in cardiovascular disease: A systematic review

INTRODUCTION

Acute exercise and exercise training may confer epigenetic modifications in healthy subjects. Epigenetic effects after exercise have been showed in patients with cardiovascular disease. The aim of this systematic review was to summarize the evidence from available clinical trials that study epigenetic adaptations after exercise in patients with cardiovascular disease.

METHODS

The search strategy was performed in PubMed and CENTRAL databases on articles published until September 2020. Studies with titles and abstracts relevant to exercise epigenetic modification applied to cardiovascular patients were fully examined. Inclusion and exclusion criteria were utilized for studies screening. Quality assessment with PEDro scale and evaluation by two independent reviewers was performed.

RESULTS

Of the 1714 articles retrieved, 88 articles were assessed for eligibility criteria and 8 articles matched our search criteria and finally included in the systematic analysis. The acute exercise epigenetic (miRNAs) effects were assessed in three studies and the chronic exercise training effects (miRNAs and DNA methylation) in six studies. The results have shown that there is possibly an acute significant exercise effect on epigenetic targets which is more evident after chronic exercise training.

CONCLUSIONS

By the present systematic review, we provide preliminary evidence of beneficial epigenetic adaptations following acute and chronic exercise in patients with cardiovascular disease. More controlled studies are needed to confirm such evidence.

Physical Exercise Protects Against Endothelial Dysfunction in Cardiovascular and Metabolic Diseases

Increasing evidence shows that endothelial cells play critical roles in maintaining vascular homeostasis, regulating vascular tone, inhibiting inflammatory response, suppressing lipid leakage, and preventing thrombosis. The damage or injury of endothelial cells induced by physical, chemical, and biological risk factors is a leading contributor to the development of mortal cardiovascular and cerebrovascular diseases. However, the underlying mechanism of endothelial injury remains to be elucidated. Notably, no drugs effectively targeting and mending injured vascular endothelial cells have been approved for clinical practice. There is an urgent need to understand pathways important for repairing injured vasculature that can be targeted with novel therapies. Exercise training-induced protection to endothelial injury has been well documented in clinical trials, and the underlying mechanism has been explored in animal models. This review mainly summarizes the protective effects of exercise on vascular endothelium and the recently identified potential therapeutic targets for endothelial dysfunction.

Recent Developments in Delivery of MicroRNAs Utilizing Nanosystems for Metabolic Syndrome Therapy

Metabolic syndrome (MetS) is a set of complex, chronic inflammatory conditions that are characterized by central obesity and associated with an increased risk of cardiovascular diseases. In recent years, microRNAs (miRNAs) have become an important type of endocrine factors, which play crucial roles in maintaining energy balance and metabolic homeostasis. However, its unfavorable properties such as easy degradation in blood and off-target effect are still a barrier for clinical application. Nanosystem based delivery possess strong protection, high bioavailability and control release rate, which is beneficial for success of gene therapy. This review first describes the current progress and advances on miRNAs associated with MetS, then provides a summary of the therapeutic potential and targets of miRNAs in metabolic organs. Next, it discusses recent advances in the functionalized development of classic delivery systems (exosomes, liposomes and polymers), including their structures, properties, functions and applications. Furthermore, this work briefly discusses the intelligent strategies used in emerging novel delivery systems (selenium nanoparticles, DNA origami, microneedles and magnetosomes). Finally, challenges and future directions in this field are discussed provide a comprehensive overview of the future development of targeted miRNAs delivery for MetS treatment. With these contributions, it is expected to address and accelerate the development of effective NA delivery systems for the treatment of MetS.

Endothelial impairment evaluation by peripheral arterial tonometry in pediatric endocrinopathies: A narrative review

Endothelial dysfunction (ED) is characterized by an imbalance between vasodilator and vasoconstriction agents. Several pathological conditions clinically diagnosed in childhood and adolescence are characterized by ED and increased risk for early development of microangiopathic and macroangiopathic impairment, in particular type 1 diabetes mellitus (T1DM), T2DM, obesity, metabolic syndromeand pituitary dysfunction associated to various endocrinopathies. More recently insulin resistance following chemotherapy or radiotherapy for tumors, bone marrow transplantation for hematological malignancies (i.e., cancer survivors), or immunosuppressive treatment for solid organ transplantation has been observed. Assessment of ED by means of non-invasive techniques is the gold standard for early ED detection before clinical manifestation. It is aimed to recognize patients at risk and to avoid the development and progression of more serious illnesses. Reactive hyperemia-peripheral artery tonometry is a noninvasive technique to assess peripheral endothelial function by measuring modifications in digital pulse volume during reactive hyperemia, and represents a non-invasive, reproducible and operator-independent tool able to detect precocious ED. This narrative review aimed to provide an overview of the most important papers regarding ED detection by EndoPat 2000 in children and adolescents with different endocrine diseases. A comprehensive search of English language articles was performed in the MEDLINE database without using other search filters except the publication interval between 2005 and 2020.

Exercise Improves Endothelial Function via the lncRNA MALAT1/miR-320a Axis in Obese Children and Adolescents

Background

Endothelial dysfunction commonly occurs in obese children and adolescents, leading to an increased risk of cardiovascular diseases. Exercise has significant protective effects against endothelial dysfunction through regulating some noncoding RNAs. This study aimed to investigate the relationship of long noncoding RNA MALAT1 and microRNA-320a (miR-320a) with the exercise-induced improvement of endothelial dysfunction in obese children and adolescents.

Methods

Sixty obese children and adolescents were included in this study, including 40 cases that received 12-week exercise training and 20 cases that received only diet control. The anthropometric and blood indices before and after exercise were recorded and compared, and the endothelial dysfunction was evaluated by examining the levels of markers, including VCAM-1, ICAM-1, and E-selectin, using an ELISA assay. The expression levels of noncoding RNAs were assessed using real-time quantitative PCR, and their correlation with patients' recorded indices and endothelial dysfunction markers was analyzed.

Results

The 12-week exercise training significantly decreased the levels of VCAM-1, ICAM-1, and E-selectin and could inhibit MALAT1 but promote miR-320a expression in obese children and adolescents. The expression of MALAT1 and miR-320a was correlated with the changes in the anthropometric and blood indices of obese children and adolescents, and their correlations with endothelial dysfunction markers were obtained.

Conclusion

All the data revealed that exercise has significantly protective effects against endothelial dysfunction and can regulate the expression of the MALAT1/miR-320a axis. MALAT1 and miR-320a were correlated with endothelial dysfunction markers, indicating that the MALAT1/miR-320a axis may be related with the alleviating effects of exercise on endothelial function in obese children and adolescents.

Tissue and circulating microRNAs as biomarkers of response to obesity treatment strategies

BACKGROUND

Obesity, characterized by an increased amount of adipose tissue, is a metabolic chronic alteration which has reached pandemic proportion. Lifestyle changes are the first line therapy for obesity and a large variety of dietary approaches have demonstrated efficacy in promoting weight loss and improving obesity-related metabolic alterations. Besides diet and physical activity, bariatric surgery might be an effective therapeutic strategy for morbid obese patients. Response to weight-loss interventions is characterised by high inter-individual variability, which might involve epigenetic factors. microRNAs have critical roles in metabolic processes and their dysregulated expression has been reported in obesity.

AIM

The aim of this review is to provide a comprehensive overview of current studies evaluating changes in microRNA expression in obese patients undergoing lifestyle interventions or bariatric surgery.

RESULTS

A considerable number of studies have reported a differential expression of circulating microRNAs before and after various dietary and bariatric surgery approaches, identifying several candidate biomarkers of response to weight loss. Significant changes in microRNA expression have been observed at a tissue level as well, with entirely different patterns between visceral and subcutaneous adipose tissue. Interestingly, relevant differences in microRNA expression have emerged between responders and non-responders to dietary or surgical interventions. A wide variety of dysregulated microRNA target pathways have also been identified, helping to understand the pathophysiological mechanisms underlying obesity and obesity-related metabolic diseases.

CONCLUSIONS

Although further research is needed to draw firm conclusions, there is increasing evidence about microRNAs as potential biomarkers for weight loss and response to intervention strategies in obesity.

LncRNA MALAT1/miR-320a axis is associated with exercise-induced improvement of endothelial dysfunction in obese children

BACKGROUND

Endothelial dysfunction commonly occurs in obese children, leading to increased risk of cardiovascular diseases. Exercise has protective effects against endothelial dysfunction through regulating some noncoding RNAs. This study aimed to investigate the relationship of long noncoding RNA MALAT1 and microRNA-320a (miR-320a) with the exercise-induced improvement of endothelial dysfunction in obese children.

METHODS

Sixty obese children were included in this study, and 40 cases received a 12-week exercise training. The morphological and blood indices before and after exercise were recorded and compared, and the endothelial dysfunction was evaluated by examining the levels of VCAM-1, ICAM-1, E-selectin, IL-6 and TNF-α using ELISA kits. The expression of noncoding RNAs was assessed using Real-Time quantitative PCR. Endothelial cells were used to explore the effects of MALAT1 and miR-320a on endothelial function.

RESULTS

The 12-well exercise training decreased the levels of VCAM-1, ICAM-1 and E-selectin, and inhibited MALAT1 but promoted miR-320a expression in obese children. The expression of MALAT1 and miR-320a was correlated with the changes of morphological and blood indices in obese children, and their correlations with endothelial dysfunction markers were obtained. Additionally, MALAT1 overexpression or miR-320a reduction led to inhibited proliferation and increased inflammation in HUVECs.

CONCLUSION

All the data revealed that exercise has significantly protective effects against endothelial dysfunction, and can regulate the expression of the MALAT1/miR-320a axis. MALAT1 and miR-320a were correlated with endothelial dysfunction, indicating that the MALAT1/miR-320a axis may be related with the alleviating effects of exercise on endothelial function in obese children.

Altered endothelial dysfunction-related miRs in plasma from ME/CFS patients

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex disease characterized by unexplained debilitating fatigue. Although the etiology is unknown, evidence supports immunological abnormalities, such as persistent inflammation and immune-cell activation, in a subset of patients. Since the interplay between inflammation and vascular alterations is well-established in other diseases, endothelial dysfunction has emerged as another player in ME/CFS pathogenesis. Endothelial nitric oxide synthase (eNOS) generates nitric oxide (NO) that maintains endothelial homeostasis. eNOS is activated by silent information regulator 1 (Sirt1), an anti-inflammatory protein. Despite its relevance, no study has addressed the Sirt1/eNOS axis in ME/CFS. The interest in circulating microRNAs (miRs) as potential biomarkers in ME/CFS has increased in recent years. Accordingly, we analyze a set of miRs reported to modulate the Sirt1/eNOS axis using plasma from ME/CFS patients. Our results show that miR-21, miR-34a, miR-92a, miR-126, and miR-200c are jointly increased in ME/CFS patients compared to healthy controls. A similar finding was obtained when analyzing public miR data on peripheral blood mononuclear cells. Bioinformatics analysis shows that endothelial function-related signaling pathways are associated with these miRs, including oxidative stress and oxygen regulation. Interestingly, histone deacetylase 1, a protein responsible for epigenetic regulations, represented the most relevant node within the network. In conclusion, our study provides a basis to find endothelial dysfunction-related biomarkers and explore novel targets in ME/CFS.

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.

Targets identified from exercised heart: killing multiple birds with one stone

Cardiovascular diseases (CVDs) are a major cause of mortality worldwide, which are mainly driven by factors such as aging, sedentary lifestyle, and excess alcohol use. Exercise targets several molecules and protects hearts against many of these physiological and pathological stimuli. Accordingly, it is widely recognized as an effective therapeutic strategy for CVD. To investigate the molecular mechanism of exercise in cardiac protection, we identify and describe several crucial targets identified from exercised hearts. These targets include insulin-like growth factor 1 (IGF1)-phosphatidylinositol 3 phosphate kinase (PI3K)/protein kinase B (AKT), transcription factor CCAAT/enhancer-binding protein β (C/EBPβ), cardiac microRNAs (miRNAs, miR-222 and miR-17-3p etc.), exosomal-miRNAs (miR-342, miR-29, etc.), Sirtuin 1 (SIRT1), and nuclear factor erythroid 2‑related factor/metallothioneins (Nrf2/Mts). Targets identified from exercised hearts can alleviate injury via multiple avenues, including: (1) promoting cardiomyocyte proliferation; (2) facilitating cardiomyocyte growth and physiologic hypertrophy; (3) elevating the anti-apoptotic capacity of cardiomyocytes; (4) improving vascular endothelial function; (5) inhibiting pathological remodeling and fibrosis; (6) promoting extracellular vesicles (EVs) production and exosomal-molecules transfer. Exercise is one treatment (‘stone’), which is cardioprotective via multiple avenues (‘birds’), and is considered ‘killing multiple birds with one stone’ in this review. Further, we discuss the potential application of EV cargos in CVD treatment. We provide an outline of targets identified from the exercised heart and their mechanisms, as well as novel ideas for CVD treatment, which may provide novel direction for preclinical trials in cardiac rehabilitation.

miR-375 Promotes Pancreatic Differentiation In Vitro by Affecting Different Target Genes at Different Stages

Human embryonic stem cells (hESCs) possess the ability to differentiate into insulin-producing cells (IPCs), which can be used to treat type I diabetes. miR-375 is an essential transcriptional regulator in the development and maturation of the pancreas. In this study, we optimized a protocol to differentiate hESCs into IPCs and successfully obtained IPCs. Then, we performed overexpression and inhibition experiments of miR-375 on cells at different stages of differentiation and performed RNA-seq. The results showed that the expression of miR-375 fluctuated during hESC differentiation and was affected by miR-375 mimics and inhibitors. miR-375 influences global gene expression and the target genes of miR-375. The overexpression of miR-375 can cause changes in multiple signaling pathways during pancreatic development. miR-375 is a major participant in the differentiation of pancreatic β-cells through different target genes at different stages. This study provides new ideas for further investigation of how microRNAs affect cell fate and gene transcription.

Modulations of obesity-related microRNAs after exercise intervention: a systematic review and bioinformatics analysis

Obesity is one of the prevalent health-threatening conditions; however, it is preventable by lifestyle interventions such as exercise. The molecular mechanisms underlying physiological adaptation to physical activity are not fully understood. It has been documented that both intracellular and extracellular (circulating) microRNAs (miRNAs) are involved in both obesogenic and exercise adaptation mechanisms. We aimed to conduct a systematic review of publications that examined the effect of exercise on the expression of miRNAs in individuals with obesity. In addition, bioinformatics analysis was performed on most repetitive miRNAs. PubMed, Scopus, and Google Scholar were searched with relevant keywords. We only included studies that utilized exercise as a modality for the health management of human subjects with obesity to evaluate the changes in expression of obesity-related miRNAs. Through checking of 211 retrieved articles, we reached 12 eligible studies. Some studies reported a statistically significant correlation between the change of miRNAs and clinical parameters such as body mass index and fasting glucose. In silico analysis of most repetitive miRNAs i.e. miR-126, miR-21, miR-146a, miR-221, and miR-223 resulted in the molecular signaling pathways that potentially involve in cellular adaption to exercise in people with obesity. miRNAs partake in health-related benefits of physical activity on obesity-associated cellular and molecular phenomena. However, our understanding of the exact mechanism is still in its infancy. Consistently, the clinicians waiting for the result of more integrated experiments to develop a miRNAs panel as a predictive biomarker of exercise in patients with obesity.

Exosomal Secretion of Adipose Tissue during Various Physiological States

Exosomes are secreted extracellular vesicles containing a wide array of biologically active components. Recent studies have demonstrated that exosomes serve as an important vehicle for extracellular communication and exert systemic effects on the physiology of organisms. Adipose tissues (ATs) play a key role in balancing systemic energy homeostasis as a central hub for fatty acid metabolism. At the same time, proper endocrine function of ATs has also been shown to be crucial for regulating physiological and metabolic health. The endocrine function of ATs is partially mediated by AT-derived exosomes that regulate metabolic homeostasis, such as insulin signaling, lipolysis, and inflammation. During the pathogenesis of obesity, metabolic syndrome, and cancer, exosomes shed by the resident cells in ATs may also have a role in regulating the progression of these diseases along with associated pathologies. In this review, we summarize the contents of AT-derived exosomes and their effects on various cell populations along with possible underlying molecular mechanisms. We further discuss the potential applications of exosomes as a drug delivery tool and therapeutic target.

Cardiovascular diseases and metabolic abnormalities associated with obesity: What is the role of inflammatory responses? A systematic review

INTRODUCTION

Obesity is a chronic disease responsible for a high morbidity and mortality rate, with an increasing worldwide prevalence. Obesity is associated with immune responses characterized by chronic systemic inflammation. This article focuses on the mechanisms that explain the proposed link between obesity-associated diseases and inflammation. Also, it describes the role of inflammatory molecules in obesity-associated metabolic abnormalities.

METHODS

More than 200 articles were selected and consulted by an online English search using various electronic search databases. Predefined key-words for the pathogenesis of obesity-induced inflammation and associated diseases, as well as the role of various inflammatory molecules, were used.

RESULTS

We have summarized the data of the articles consulted in this research and we have found that obesity is associated with a low-grade inflammation resulting from the change of adipose tissue (AT). The AT produces a variety of inflammatory molecules called adipocytokines that are involved in the onset of systemic low-grade inflammation which is the link between obesity and associated-chronic abnormalities; such as insulin resistance, metabolic syndrome, cardiovascular disease (CVD), hypertension, diabetes, and some cancers. Also, we have searched all the inflammatory molecules involved in this pathogenesis and we have briefly described the role of 16 of them which are the most related to obesity-associated inflammation. The results have shown that there are inflammatory molecules that have a positive relationship with the pathogenesis of obesity-related diseases and others have a negative relationship with this pathogenesis.

CONCLUSION

Inflammation plays a crucial role in the development of various metabolic-abnormalities related to obesity. In this regard, the management of obesity may help reduce the risk of cardiovascular disease and other metabolic complications by inhibiting inflammatory mechanisms.

Evaluation of Vascular Endothelial Function in Young and Middle-Aged Women with Respect to a History of Pregnancy, Pregnancy-Related Complications, Classical Cardiovascular Risk Factors, and Epigenetics

The aim of the study was to examine the effect of previous pregnancies and classical cardiovascular risk factors on vascular endothelial function in a group of 264 young and middle-aged women 3 to 11 years postpartum. We examined microvascular functions by peripheral arterial tonometry and EndoPAT 2000 device with respect to a history of gestational hypertension, preeclampsia, fetal growth restriction, the severity of the disease with regard to the degree of clinical signs and delivery date. Besides, we compared Reactive Hyperemia Index (RHI) values and the prevalence of vascular endothelial dysfunction among the groups of women with normal and abnormal values of BMI, waist circumference, systolic and diastolic blood pressures, heart rate, total serum cholesterol levels, serum high-density lipoprotein cholesterol levels, serum low-density lipoprotein cholesterol levels, serum triglycerides levels, serum lipoprotein A levels, serum C-reactive protein levels, serum uric acid levels, and plasma homocysteine levels. Furthermore, we determined the effect of total number of pregnancies and total parity per woman, infertility and blood pressure treatment, presence of trombophilic gene mutations, current smoking of cigarettes, and current hormonal contraceptive use on the vascular endothelial function. We also examined the association between the vascular endothelial function and postpartum whole peripheral blood expression of microRNAs involved in pathogenesis of cardiovascular/cerebrovascular diseases (miR-1-3p, miR-16-5p, miR-17-5p, miR-20a-5p, miR-20b-5p, miR-21-5p, miR-23a-3p, miR-24-3p, miR-26a-5p, miR-29a-3p, miR-92a-3p, miR-100-5p, miR-103a-3p, miR-125b-5p, miR-126-3p, miR-130b-3p, miR-133a-3p, miR-143-3p, miR-145-5p, miR-146a-5p, miR-155-5p, miR-181a-5p, miR-195-5p, miR-199a-5p, miR-210-3p, miR-221-3p, miR-342-3p, miR-499a-5p, and miR-574-3p). A proportion of overweight women (17.94% and 20.59%) and women with central obesity (18.64% and 21.19%) had significantly lower RHI values at 10.0% false positive rate (FPR) both before and after adjustment of the data for the age of patients. At 10.0% FPR, a proportion of women with vascular endothelial dysfunction (RHI ≤ 1.67) was identified to have up-regulated expression profile of miR-1-3p (11.76%), miR-23a-3p (17.65%), and miR-499a-5p (18.82%) in whole peripheral blood. RHI values also negatively correlated with expression of miR-1-3p, miR-23a-3p, and miR-499a-5p in whole peripheral blood. Otherwise, no significant impact of other studied factors on vascular endothelial function was found. We suppose that screening of these particular microRNAs associated with vascular endothelial dysfunction may help to stratify a highly risky group of young and middle-aged women that would benefit from early implementation of primary prevention strategies. Nevertheless, it is obvious, that vascular endothelial dysfunction is just one out of multiple cardiovascular risk factors which has only a partial impact on abnormal expression of cardiovascular and cerebrovascular disease associated microRNAs in whole peripheral blood of young and middle-aged women.

Exercise-associated prevention of adult cardiovascular disease in children and adolescents: monocytes, molecular mechanisms, and a call for discovery

Atherosclerosis originates in childhood and adolescence. The goal of this review is to highlight how exercise and physical activity during childhood and adolescence, critical periods of growth and development, can prevent adult cardiovascular disease (CVD), particularly through molecular mechanisms of monocytes, a key cell of the innate immune system. Monocytes are heterogeneous and pluripotential cells that can, paradoxically, play a role in both the instigation and prevention of atherosclerosis. Recent discoveries in young adults reveal that brief exercise affects monocyte gene pathways promoting a cell phenotype that patrols the vascular system and repairs injuries. Concurrently, exercise inhibits pro-inflammatory monocytes, cells that contribute to vascular damage and plaque formation. Because CVD is typically asymptomatic in youth, minimally invasive techniques must be honed to study the subtle anatomic and physiologic evidence of vascular dysfunction. Exercise gas exchange and heart rate measures can be combined with ultrasound assessments of vascular anatomy and reactivity, and near-infrared spectroscopy to quantify impaired O2 transport that is often hidden at rest. Combined with functional, transcriptomic, and epigenetic monocyte expression and measures of monocyte-endothelium interaction, molecular mechanisms of early CVD can be formulated, and then translated into effective physical activity-based strategies in youth to prevent adult-onset CVD.

The clinical potential of circulating microRNAs in obesity

Obesity is a complex condition that is characterized by excessive fat accumulation, which can lead to the development of metabolic disorders, such as type 2 diabetes mellitus, nonalcoholic fatty liver disease and cardiovascular diseases. Evidence is accumulating that circulating microRNAs (miRNAs) act as a new class of endocrine factor. These miRNAs are released by many types of tissue, including adipose tissues. miRNAs might serve as endocrine and paracrine messengers that facilitate communication between donor cells and tissues with receptor cells or target tissues, thereby potentially having important roles in metabolic organ crosstalk. Moreover, many miRNAs are closely associated with the differentiation of adipocytes and are dysregulated in obesity. As such, circulating miRNAs are attractive potential biomarkers and hold promise for the development of miRNA-based therapeutics (such as miRNA mimetics, anti-miRNA oligonucleotides and exosomes loaded with miRNA) for obesity and related disorders. Here we review the latest research progress on the roles of circulating miRNAs in metabolic organ crosstalk. In addition, we discuss the clinical potential of circulating miRNAs as feasible biomarkers for the assessment of future risk of metabolic disorders and as therapeutic targets in obesity and related diseases.

The effects of moderate and high-intensity exercise on circulating markers of endothelial integrity and activation in young, healthy men

Endothelial function typically exhibits a hormetic response to exercise. It is unknown whether endothelial damage occurs in response to acute exercise and could be a contributing mechanism. We sought to determine the effects of acute exercise on endothelial-derived circulating factors proposed to reflect endothelial integrity and activation. Young, healthy men (n = 10) underwent 30-min moderate continuous (MOD) and high-intensity interval (HII) cycling exercise bouts. Venous blood samples were taken immediately before and after exercise for quantification of circulating endothelial cells (CECs), circulating angiogenic cells (CACs), apoptotic and activated endothelial microvesicles (EMVs), thrombomodulin (TM), von Willebrand factor (vWF), syndecan-1, and circulating microRNAs (ci-miRs) 126-3p and 126-5p. Endothelial function was assessed by flow-mediated dilation (FMD) of the brachial artery before, 10 min after, and 60 min after exercise. Numbers of CECs and EMVs were unchanged by either exercise bout (P > 0.05). Numbers of all measured CAC subtypes decreased in response to MOD (21%-34%, P < 0.05), whereas only CD31⁺/34⁺/45^dim/- CACs decreased following HII (21%, P < 0.05). TM and syndecan-1 increased with both exercise intensities (both ~20%, P < 0.05). HII, but not MOD, increased vWF (88%, P < 0.001), ci-miR-126-3p (92%, P = 0.009) and ci-miR-126-5p (110%, P = 0.01). The changes in several circulating factors correlated with changes in FMD following either one or both intensities. Changes in circulating factors do not support the concept of exercise-induced endothelial cell denudation, apoptosis, or activation, though slight disruption of endothelial glycocalyx and membrane integrity may occur. A related loss of mechanotransduction along with mechanisms underlying endothelial activation and ci-miR-126 secretion may relate to changes in endothelial function.NEW & NOTEWORTHY Using circulating endothelial-derived factors, we show that endothelial denudation, apoptosis, and activation do not appear to increase, whereas disrupted endothelial glycocalyx and membrane integrity may occur during both high-intensity interval and moderate intensity cycling. Increases in factors nonspecific to endothelial damage, including von Willebrand factor and microRNA-126, occurred only after high-intensity interval exercise. These results shed light on the hypothesis that disrupted endothelial integrity contributes to the endothelial function response to exercise.