Effect of exercise training on endothelium-derived nitric oxide function in humans

Stroke Incidence in Patients With Hypertension According to Cardiorespiratory Fitness

BACKGROUND

Hypertension and physical inactivity are risk factors for stroke. The effect of cardiorespiratory fitness (CRF) on stroke risk in patients with hypertension has not been assessed. We evaluated stroke incidence in patients with hypertension according to CRF and changes in CRF.

METHODS

We included 483 379 patients with hypertension (mean age±SD; 59.4±9.0 years) and no evidence of unstable cardiovascular disease as indicated by a standardized exercise treadmill test. Patients were assigned to 5 age- and sex-specific CRF categories based on peak metabolic equivalents achieved at the initial exercise treadmill test and in 4 categories based on metabolic equivalent changes over time (n=110 576). Multivariable Cox models, adjusted for age, and comorbidities were used to estimate hazard ratios and 95% CIs for stroke risk.

RESULTS

During a median follow-up of 10.6 (interquartile range, 6.6-14.6) years, 15 925 patients developed stroke with an average yearly rate of 3.1 events/1000 person-years. Stroke risk declined progressively with higher CRF and was 55% lower for the High-fit individuals (hazard ratio, 0.45 [95% CI, 0.42-0.48]) compared with the Least-fit. Similar associations were observed across the race, sex, and age spectra. Poor CRF was the strongest predictor of stroke risk of all comorbidities studied (hazard ratio, 2.24 [95% CI, 2.10-2.40]). Changes in CRF reflected inverse and proportional changes in stroke risk.

CONCLUSIONS

Poor CRF carried a greater risk than any of the cardiac risk factors in patients with hypertension, regardless of age, race, or sex. The lower stroke risk associated with improved CRF suggests that increasing physical activity, even later in life, may reduce stroke risk.

Exercise-Induced Oxygen Desaturation Increases Arterial Stiffness in Patients with COPD During the 6WMT

Objective

Given the established impact of exercise in reducing arterial stiffness and the potential for intermittent hypoxia to induce its elevation, this study aims to understand how oxygen desaturation during exercise affects arterial stiffness in individuals with COPD.

Methods

We enrolled patients with stable COPD from China-Japan Friendship Hospital from November 2022 to June 2023. The 6-minute walk test (6-MWT) was performed with continuous blood oxygen saturation (SpO2) monitoring in these patients. The patients were classified into three groups: non-exercise induced desaturation (EID), mild-EID and severe-EID, according to the changes in SpO2 during the 6-MWT. The Cardio-Ankle Vascular Index (CAVI) and the change in CAVI (ΔCAVI, calculated as CAVI before 6MWT minus CAVI after the 6MWT) were measured before and immediately after the 6MWT to assess the acute effects of exercise on arterial stiffness. GOLD Stage, pulmonary function, and other functional outcomes were also measured in this study.

Results

A total of 37 patients with stable COPD underwent evaluation for changes in CAVI (ΔCAVI) before and after the 6-MWT. Stratification based on revealed three subgroups: non-EID (n=12), mild-EID (n=15), and severe-EID (n=10). The ΔCAVI values was -0.53 (-0.95 to -0.31) in non-EID group, -0.20 (-1.45 to 0.50) in mild-EID group, 0.6 (0.08 to 0.73) in severe-EID group. Parametric tests indicated significant differences in ΔCAVI among EID groups (p = 0.005). Pairwise comparisons demonstrated significant distinctions between mild-EID and severe-EID groups, as well as between non-EID and severe-EID groups (p = 0.048 and p = 0.003, respectively). Multivariable analysis, adjusting for age, sex, GOLD stage, diffusion capacity, and blood pressure, identified severe-EID as an independent factor associated with ΔCAVI (B = 1.118, p = 0.038).

Conclusion

Patients with COPD and severe-EID may experience worsening arterial stiffness even during short periods of exercise.

Impact of supra-maximal interval training vs. high-intensity interval training on cardiac auto-regulation response in physically active adults

PURPOSE

This study aimed to examine the impact of supra-maximal interval training (SMIT) and high-intensity interval training (HIIT) on cardiac auto-regulation response.

METHODS

Physically active young adults volunteered to participate in the study with a randomized cross-over counterbalanced design (N = 12). HIIT sessions consisted of 20 bouts of 10 s of exercise followed by 50 s of recovery, totaling 20 min at two different intensities; "all-out (SMIT)" vs. "115-130% Wmax (HIIT)". The cardiac auto-regulation included heart rate variability (HRV) and vascular function. HRV and vascular function were measured at baseline and five different time points after acute exercise.

RESULTS

The SMIT was higher in workload (31%), peak heart rate (28%), and rate of perceived exertion (40%) compared with HIIT (all p < 0.001). The R-R interval, NN50, and pNN50 measured until 60 min after acute exercise was higher in the HIIT compared with SMIT (all p < 0.05). The SMIT elicited a greater shift in ln LF/HF ratio immediately after acute exercise (3802%, p < 0.01) and induced a decrease in bilateral ba-PWV at the time point 5 min after acute exercise, persisting until 65 min after (p < 0.05). Yet, HIIT showed no change over time in the frequency domain of HRV and blood vascular tone after cessation of acute exercise.

CONCLUSION

Our findings confirmed that SMIT is a more potent modulator of the autonomic nervous system compared with HIIT. Further study is needed to monitor through complete recovery to baseline, to understand acute cardiac auto-regulation response after cessation of various exercise intensities identical interval training protocol.

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.

Non-neuronal cell-derived acetylcholine, a key modulator of the vascular endothelial function in health and disease

Vascular endothelial cells play an important role in regulating peripheral circulation by modulating arterial tone in the microvasculature. Elevated intracellular Ca2+ levels are required in endothelial cells to induce smooth muscle relaxation via endothelium-dependent mechanisms such as nitric oxide production, prostacyclin, and endothelial cell hyperpolarization. It is well established that exogenous administration of acetylcholine can increase intracellular Ca2+ concentrations, followed by endothelium-dependent vasodilation. Although endogenous acetylcholine's regulation of vascular tone remains debatable, recent studies have reported that endogenously derived acetylcholine, but not neuronal cell-derived acetylcholine, is a key modulator of endothelial cell function. In this minireview, we summarize the current knowledge of the non-neuronal cholinergic system (NNCS) in vascular function, particularly vascular endothelial cell function, which contributes to blood pressure regulation. We also discuss the possible pathophysiological impact of endothelial NNCS, which may induce the development of vascular diseases due to endothelial dysfunction, and the potential of endothelial NNCS as a novel therapeutic target for endothelial dysfunction in the early stages of metabolic syndrome, diabetes, and hypertension.

Is It Possible to Train the Endothelium?-A Narrative Literature Review

This review provides an overview of current knowledge regarding the adaptive effects of physical training on the endothelium. The endothelium plays a crucial role in maintaining the health of vessel walls and regulating vascular tone, structure, and homeostasis. Regular exercise, known for its promotion of cardiovascular health, can enhance endothelial function through various mechanisms. The specific health benefits derived from exercise are contingent upon the type and intensity of physical training. The review examines current clinical evidence supporting exercise's protective effects on the vascular endothelium and identifies potential therapeutic targets for endothelial dysfunction. There is an urgent need to develop preventive strategies and gain a deeper understanding of the distinct impacts of exercise on the endothelium.

Exercise-induced changes in lower limbs skin temperature against plasma ATP among individuals with various type and level of physical activity

The objective of the study was to examine the lower limbs skin temperature (TSK) changes in response to exhaustive whole-body exercise in trained individuals in reference to changes in plasma adenosine triphosphate (ATP). Eighteen trained participants from distinct sport type ‒ endurance (25.2 ± 4.9 yr) and speed-power (25.8 ± 3.1 yr), and 9 controls (24,9 ± 4,3 yr) ‒ were examined. Lower limbs TSK and plasma ATP measures were applied in parallel in response to incremental treadmill test and during 30-min recovery period. Plasma ATP kinetics were inversely associated to changes in TSK. The first significant decrease in TSK (76-89% of V˙ O2MAX) occurred shortly before a significant plasma ATP increase (86-97% of V˙ O2MAX). During recovery, TSK increased, reaching pre-exercise values (before exercise vs. after 30-min recovery: 31.6 ± 0.4 °C vs. 32.0 ± 0.8 °C, p = 0.855 in endurance; 32.4 ± 0.5 °C vs. 32.9 ± 0.5 °C, p = 0.061 in speed-power; 31.9 ± 0.7 °C vs. 32.4 ± 0.8 °C, p = 0.222 in controls). Plasma ATP concentration did not returned to pre-exercise values in well trained participants (before exercise vs. after 30-min recovery: 699 ± 57 nmol l-1 vs. 854 ± 31 nmol l-1, p < 0.001, η2 = 0.961 and 812 ± 35 nmol l-1 vs. 975 ± 55 nmol l-1, p < 0.001, η2 = 0.974 in endurance and speed-power, respectively), unlike in controls (651 ± 40 nmol l-1 vs. 687 ± 61 nmol·l-1, p = 0.58, η2 = 0.918). The magnitude of TSK and plasma ATP response differed between the groups (p < 0.001, η2 = 0.410 for TSK; p < 0.001, η2 = 0.833 for plasma ATP). We conclude that lower limbs TSK change indirectly corresponds to the reverse course of plasma ATP during incremental exercise and the magnitude of the response depends on the level of physical activity and the associated to it long-term metabolic adaptation.

Review of cardiac-coronary interaction and insights from mathematical modeling

Cardiac-coronary interaction is fundamental to the function of the heart. As one of the highest metabolic organs in the body, the cardiac oxygen demand is met by blood perfusion through the coronary vasculature. The coronary vasculature is largely embedded within the myocardial tissue which is continually contracting and hence squeezing the blood vessels. The myocardium-coronary vessel interaction is two-ways and complex. Here, we review the different types of cardiac-coronary interactions with a focus on insights gained from mathematical models. Specifically, we will consider the following: (1) myocardial-vessel mechanical interaction; (2) metabolic-flow interaction and regulation; (3) perfusion-contraction matching, and (4) chronic interactions between the myocardium and coronary vasculature. We also provide a discussion of the relevant experimental and clinical studies of different types of cardiac-coronary interactions. Finally, we highlight knowledge gaps, key challenges, and limitations of existing mathematical models along with future research directions to understand the unique myocardium-coronary coupling in the heart. This article is categorized under: Cardiovascular Diseases > Computational Models Cardiovascular Diseases > Biomedical Engineering Cardiovascular Diseases > Molecular and Cellular Physiology.

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.

Effects of high-intensity interval exercise on arterial stiffness in individuals at risk for cardiovascular disease: a meta-analysis

Objective

The purpose of this meta-analysis was to investigate the effect of high-intensity interval training (HIIT) on arterial stiffness (AS) and vascular function in persons at high risk of cardiovascular disease (CVD).

Methods

We conducted a comprehensive search of randomized controlled trials (RCTs) published in electronic databases (PubMed, Web of Science, Cochrane, Embase, and Ebsco) since their inception through October 2023 to evaluate the effect of HIIT on AS and vascular function in persons at high risk for CVD. The weighted mean difference (WMD) and 95% confidence intervals (95% CI) were calculated, and heterogeneity was assessed using the I2 test.

Results

This study included 661 participants from 16 studies. HIIT significantly reduced pulse wave velocity (PWV) in persons at high risk for CVD [weighted mean difference (WMD), -0.62; 95% CI, -0.86--0.38; P < 0.00001]. Subgroup analysis showed that the PWV improvement effect was better when the HIIT program was performed 2-3 times per week and the duration was controlled within 40 min [2-3 times, -0.67; 95% CI, -0.93--0.41; P < 0.00001; time of duration, ≤40 min, -0.66; 95% CI, -0.91--0.41; P < 0.00001]. HIIT significantly reduced systolic blood pressure (SBP, -5.43; 95% CI, -8.82--2.04; P = 0.002), diastolic blood pressure (DPB, -2.96; 95% CI, -4.88--1.04; P = 0.002), and resting heart rate (RHR, -4.35; 95% CI, -7.04--1.66; P = 0.002), but had no significant effect on augmentation index (AIX, -2.14; 95% CI, -6.77-2.50; P = 0.37).

Conclusion

HIIT can improve PWV in high-risk individuals with CVD and reduce SBP, DBP, and RHR, but has no significant effect on AIX. HIIT can effectively improve AS and vascular function and can be recommended as an effective method to improve AS in high-risk persons with CVD.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42023471593.

Active intervals between sets and exercise of resistance exercises potentiate the magnitude of post-exercise hypotension in middle-aged hypertensive women

BACKGROUND

Walking/run promotes greater post-exercise hypotension (PEH) than resistance exercise (RE) which can be associated nitric oxide production. Then, we investigated if adding walking between RE increases PEH.

METHODS

Thirteen hypertensive women (48 ± 1.9 years; 26.8 ± 0.3 kg/m2) performed five experimental sessions: 1-traditional RE with passive interval (PIBS); 2-RE with active interval between sets (AIBS); 3-RE with active interval between exercises (AIEX); 4-aerobic exercise (AE); 5-no exercise. Blood pressure was measured before and immediately after exercise and every 10 min of a 60-min post-exercise recovery period. Plasma nitrite (NO) and malondialdehyde (MDA) were also measured.

RESULTS

AIBS, AIEX, and AE sessions promoted systolic PEH (12 ± 1.53; 16 ± 2.13; 18 ± 1.34 mmHg, respectively) and diastolic PEH (8 ± 1.38; 8 ± 0.79; 8 ± 0.58 mmHg). In AIBS, AIEX and AE sessions, significant PEH was noted at 10 or 20 min; in PIBS, PEH was significant only at 40 min. In the PIBS session, NO did not change, but presented higher values after AIBS, AIEX and AE sessions. MDA showed no changes between sessions.

CONCLUSIONS

Passive or active intervals in resistance exercise promote PEH in hypertensive women. Active intervals shorten the PEH onset time as additional benefit.

Exploring the Potential Benefits of Interventions When Addressing Simulated Altitude Hypoxia during Male Cyclist Sports: A Systematic Review

Training in hypoxic environments enhances endurance, but the various influences of training protocols and supplementation for efficient performance are not yet clear. This systematic review explored the effects of different supplementations and interventions used to optimize the aerobic and anaerobic performance of cyclists. Data were collected from the following sources: PubMed, Google Scholar, EMBASE, WOS, Cochrane Central Register of Controlled Trials, and randomized controlled trials (RCTs). Studies that explored the effects of supplementation or intervention during cycling were selected for analysis. Five studies (67 male cyclists; mean age, 23.74–33.56 years) reported different outcomes from supplementation or intervention during the acute hypoxia of cyclists. Three studies (42 male cyclists; mean age, 25.88–36.22 years) listed the benefits of beetroot juice in preserving SpO2 (pulse oxygen saturation) and enhancing high-intensity endurance performance, effectively preventing the reduction in power output. This systematic review provided evidence that the different effects of ischemic preconditioning (IPC), sildenafil, and beetroot (BR) supplementation and intervention did not present a statistically greater benefit than for normoxia groups, but BR supplementation promoted the benefits of SpO2. Future research should evaluate the duration and higher FiO2 (simulated altitude, hypoxia) levels of hypoxia in training protocols for cyclists. This is important when determining the effectiveness of supplements or interventions in hypoxic conditions and their impact on sports performance, particularly in terms of power output.

Impact of Forced Swimming Stress on Serum Adiponectin and Endothelin-1 Levels in Wistar Rats: Comparative Analysis of Dietary Effects

Aim This study aimed to assess the impact of forced repeated swimming stress on serum adiponectin and endothelin-1 levels in Wistar rats, comparing the effects between those fed a standard diet and those on a high-fat diet. Methods Twenty adult male Wistar rats were divided into two dietary groups: a standard food diet group (NFD, n=10) and a high-fat diet group (HFD, n=10). Both groups underwent daily forced swimming stress for six days, with durations increasing from 5 to 30 minutes. The protocol finished in an acute bout of swimming exercise on the seventh day with a duration of 40 minutes. Adherence to ethical guidelines was strictly maintained, and serum adiponectin and endothelin-1 levels were measured pre- and post-exercise using the ELISA method. Results Before swimming, the mean adiponectin levels were 4.30±1.50 ng/mL in the NFD group and 3.53±0.70 ng/mL in the HFD group. Post-exercise, these levels significantly decreased to 2.4±0.84 ng/mL (p=0.003) and 1.58±0.23 ng/mL (p=0.001), respectively. Endothelin-1 levels also showed significant decreases from 0.86 pg/mL (0.74-0.87) to 0.49 pg/mL (0.43-0.62) (p=0.003) in the NFD group, and from 0.89 pg/mL (0.86-0.93) to 0.69 pg/mL (0.60-0.75) (p=0.027) in the HFD group after swimming. Conclusion The study highlighted the significant effects of forced swimming stress on lowering serum adiponectin and endothelin-1 levels in Wistar rats, with more pronounced decreases observed in rats on a high-fat diet. The results of the study suggest the potential of exercise as a crucial component of strategies aimed at managing obesity and improving cardiovascular health, emphasizing the interaction between physical stress and dietary factors on metabolic and cardiovascular biomarkers.

Making the case for resistance training in improving vascular function and skeletal muscle capillarization

Through decades of empirical data, it has become evident that resistance training (RT) can improve strength/power and skeletal muscle hypertrophy. Yet, until recently, vascular outcomes have historically been underemphasized in RT studies, which is underscored by several exercise-related reviews supporting the benefits of endurance training on vascular measures. Several lines of evidence suggest large artery diameter and blood flow velocity increase after a single bout of resistance exercise, and these events are mediated by vasoactive substances released from endothelial cells and myofibers (e.g., nitric oxide). Weeks to months of RT can also improve basal limb blood flow and arterial diameter while lowering blood pressure. Although several older investigations suggested RT reduces skeletal muscle capillary density, this is likely due to most of these studies being cross-sectional in nature. Critically, newer evidence from longitudinal studies contradicts these findings, and a growing body of mechanistic rodent and human data suggest skeletal muscle capillarity is related to mechanical overload-induced skeletal muscle hypertrophy. In this review, we will discuss methods used by our laboratories and others to assess large artery size/function and skeletal muscle capillary characteristics. Next, we will discuss data by our groups and others examining large artery and capillary responses to a single bout of resistance exercise and chronic RT paradigms. Finally, we will discuss RT-induced mechanisms associated with acute and chronic vascular outcomes.

Effect of Regular Training on Platelet Function in Untrained Thoroughbreds

Training has a significant effect on the physiology of blood coagulation in humans and in horses. Several hemostatic changes have been reported after exercise in the horse but data available are inconclusive. The aim of this study was to investigate platelet activation and primary platelet-related hemostasis modifications in young never-trained Thoroughbreds in the first incremental training period in order to improve knowledge on this topic. Twenty-nine clinically healthy, untrained, 2-year-old Thoroughbred racehorses were followed during their incremental 4-month sprint exercise training. Blood collection was performed once a month, five times in total (T-30, T0, T30, T60, and T90). Platelet aggregation was measured by light transmission aggregometry in response to various agonists: adenosine diphosphate (ADP), collagen, and calcium ionophore A23187. Platelet function was evaluated using a platelet function analyzer (PFA-100®) using collagen/ADP and collagen/adrenaline cartridges. Nitrite-nitrate (NOx) plasma concentrations were measured via a colorimetric assay to assess in vivo nitric oxide bioavailability. Platelet activation was also investigated through gene expression analyses (selectin P-SELP, ectonucleotidase CD39-ENTPD1, prostaglandin I2 synthase-PTGIS, endothelial nitric oxide synthase 3-NOS3). Differences among the time points were analyzed and mean ± SEM were calculated. Significant modifications were identified compared with T-30, with an increase in platelet aggregation (collagen:32.6 ± 4.8 vs. 21.6 ± 4.9%; ADP: 35.5 ± 2.0 vs. 24.5 ± 3.1%; A23187: 30 ± 4.7 vs. 23.8 ± 4%) and a shorter closure time of C-ADP cartridges (75.6 ± 4.4 vs. 87.7 ± 3.4 s) that tended to return to the baseline value at T90. NOx concentrations in plasma significantly increased after 30 days of the training program compared with the baseline. The first long-term training period seems to induce platelet hyperactivity after 30 days in never-trained Thoroughbreds. Regular physical training reduces the negative effects of acute efforts on platelet activation.

Effect of exercises on the maturation of newly created arteriovenous fistulas over distal and proximal upper limb: A systematic review and meta-analysis

The aims of our review were: (i) to evaluate the effect of post-operative upper extremity exercise on maturation of AVFs, stratified by their locations. (ii) To evaluate the effect of pre-operative arm exercise on patients' superficial vein caliber of patients. Literature search was performed on PubMed, Cochrane Library, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and China National Knowledge Infrastructure (CNKI) to identify eligible articles. The quality of the randomized controlled trials (RCTs) were assessed using the Cochrane Risk of Bias tool 2.0. In the Meta-analysis, Risk ratios (RRs) of clinical maturation and ultrasonographic maturation were pooled from studies focused on post-operative exercise program; Mean difference (MD) of venous caliver was pooled from those studied pre-operative exercise. Nine studies (six for post-operative exercise; three for pre-operative exercise) were included in the review. Among the AVFs created in distal region (158 patients in exercise group and 144 patients in control group), there was a significantly superior clinical maturation (RR: 1.28; 95% CI: 1.10-1.48, p = 0.001; I2 = 0), and ultrasonographic maturation (RR: 1.30; 95% CI: 1.07-1.59, p = 0.009; I2 = 0) in the exercise group in comparison to the control group. For the AVFs created in proximal region (93 and 96 patients in exercise group and control group respectively), there is no significant difference in clinical maturation (RR:1.25, 95% CI: 0.88-1.78, p = 0.27, I2 = 74%) and ultrasonographic maturation (RR: 1.17, 95% CI: 0.97-1.40, p = 0.11, I2 = 43%) between the exercise group and controls. For pre-operative exercise, the mean difference of 0.34 mm (95% CI: 0.23-0.46, p < 0.001, I2 = 87% ) was found for vein size. In conclusion, existing upper extremity exercise programs appear to be useful in facilitating maturation of AVFs created in distal region, while its effect on fistulas created in proximal region is less certain. However, more robust trials are warranted to establish these findings.

Balancing the value and risk of exercise-based therapy post-COVID-19: a narrative review

Coronavirus disease 2019 (COVID-19) can lead to ongoing symptoms such as breathlessness, fatigue and muscle pain, which can have a substantial impact on an individual. Exercise-based rehabilitation programmes have proven beneficial in many long-term conditions that share similar symptoms. These programmes have favourably influenced breathlessness, fatigue and pain, while also increasing functional capacity. Exercise-based rehabilitation may benefit those with ongoing symptoms following COVID-19. However, some precautions may be necessary prior to embarking on an exercise programme. Areas of concern include ongoing complex lung pathologies, such as fibrosis, cardiovascular abnormalities and fatigue, and concerns regarding post-exertional symptom exacerbation. This article addresses these concerns and proposes that an individually prescribed, symptom-titrated exercise-based intervention may be of value to individuals following infection with severe acute respiratory syndrome coronavirus 2.

Arterial Stiffness, Assessed Using the Cardio-Ankle Vascular Index, before and 2 Years after Total Knee Arthroplasty in Patients with Knee Osteoarthritis

Purpose: Cardiovascular disease (CVD) is a major risk factor for mortality in patients with osteoarthritis, and such comorbidities increase the risk of postoperative complications following total knee arthroplasty (TKA). Arteriosclerosis plays a major role in hemodynamic dysfunction and CVD; however, the postoperative changes in arteriosclerosis following TKA have not been evaluated. Therefore, we assessed the postoperative changes in arteriosclerosis using the cardio-ankle vascular index (CAVI) in patients undergoing TKA, and its relationships with preoperative patient characteristics. Methods: Arteriosclerosis was prospectively evaluated in 119 consecutive patients (140 knees) (15 males (17), 104 females (123); median age 73 years) with knee osteoarthritis who underwent TKA. CAVI was measured before and 2 years after TKA, and the relationships between CAVI and preoperative age, sex, BMI, physical activity status, comorbidities, clinical score, triglyceride concentration, cholesterol concentration, and smoking history were analyzed. Results: CAVI remained stable or improved in 54 joints (39%) and worsened in 86 joints (61%) 2 years post-operation. The median difference between pre- and postoperative CAVI was 0.2 (-0.3, 0.8), and the only preoperative factor associated with this change was preoperative CAVI (r = -0.469, p < 0.001). No other preoperative factor had a significant effect on postoperative arteriosclerosis. Conclusions: The results suggest that patients who undergo TKA subsequently show less severe arteriosclerosis, and the protective effect of TKA on arterial stiffness is greater in those with a higher preoperative CAVI. TKA may be an effective means of reducing the deterioration of arteriosclerosis associated with knee osteoarthritis, at least in the relatively short term.

Arterial stiffness and hypertension

Arterial stiffness and hypertension are closely related in pathophysiology. Chronic high blood pressure (BP) can lead to arterial wall damage by mechanical stress, endothelial dysfunction, increased inflammation, oxidative stress, and renin-angiotensin-aldosterone system (RAAS) activation. Hypertension also increases collagen fiber production and accelerates elastin fiber degradation. Stiffened arteries struggle with BP changes, raising systolic BP and pulse pressure. The resulting increased systolic pressure further hardens arteries, creating a harmful cycle of inflammation and calcification. Arterial stiffness data can predict target organ damage and future cardiovascular events in hypertensive patients. Thus, early detection of arterial stiffness aids in initiating preventive measures and treatment plans to protect against progression of vascular damage. While various methods exist for measuring arterial stiffness, pulse wave velocity is a non-invasive, simple measurement method that maximizes effectiveness. Healthy lifestyle changes, RAAS blockers, and statins are known to reduce arterial stiffness. Further research is needed to ascertain if improving arterial stiffness will enhance prognosis in hypertensive patients.

Supplementation with l-arginine and nitrates vs age and individual physiological reactivity

Ageing is a natural ontogenetic phenomenon that entails a decrease in the adaptive capacity of the organism, as a result of which the body becomes less adaptable to stressful conditions. Nitrate and nitrite enter the body from exogenous sources and from nitrification of ammonia nitrogen by intestinal microorganisms. This review considers the mechanisms of action of l-arginine, a known inducer of nitric oxide (NO) biosynthesis, and nitrates as supplements in the processes of ageing and aggravated stress states, in which mechanisms of individual physiological reactivity play an important role. This approach can be used as an element of individual therapy or prevention of premature ageing processes depending on the different levels of initial reactivity of the functional systems. A search was performed of the PubMed, Scopus, and Google Scholar databases (n = 181 articles) and the author's own research (n = 4) up to May 5, 2023. The review presents analyses of data on targeted treatment of NO generation by supplementation with l-arginine or nitrates, which is a promising means for prevention of hypoxic conditions frequently accompanying pathological processes in an ageing organism. The review clarifies the role of the individual state of physiological reactivity, using the example of individuals with a high predominance of cholinergic regulatory mechanisms who already have a significant reserve of adaptive capacity. In studies of the predominance of adrenergic influences, a poorly trained organism as well as an elderly organism correspond to low resistance, which is an additional factor of damage at increased energy expenditure. Conclusion: It is suggested that the role of NO synthesis from supplementation of dietary nitrates and nitrites increases with age rather than from oxygen-dependent biosynthetic reactions from l-arginine supplementation.

Effects of Flavonoid Supplementation on Athletic Performance in Healthy Adults: A Systematic Review and Meta-Analysis

Flavonoids, known for their antioxidant properties, can prevent reactive oxygen species (ROS) and influence athletic performance through various physiological and metabolic mechanisms. However, there are conflicting results after summarizing and analyzing the relevant literature. Hence, it is warranted to evaluate the overall impact of flavonoids on athletic performance in healthy adults based on a comprehensive and systematic review and meta-analysis. After searching four databases for literature published since their respective establishments until February 2023 and conducting publication bias and quality assessments, a total of 22 studies were ultimately included. The names and doses of flavonoids, various outcome measurements, as well as types of training, were extracted from included studies. The athletic performance outcomes from the included studies were categorized into 'performance tests' and 'exercise tolerance,' depending on the type of training undertaken. Several statistical results, such as pooled effect size (ES), among others, were implemented by meta-analysis using the random effects model. The results of meta-analysis suggest that there is currently sufficient evidence (ES = -0.28; 95% confidence interval (CI): [-0.50, -0.07]; p = 0.01 and ES = 0.23; 95% CI: [0.07, 0.39]; p = 0.005) to support the notion that flavonoid supplementation enhanced athletic performance in performance tests and exercise tolerance. In addition, among the subgroups, nonsignificant results were observed for athletes (p = 0.28) and acute supplementation (p = 0.41) in performance tests, as well as athletes (p = 0.57) and acute supplementation (p = 0.44) in exercise tolerance. Meanwhile, significant results were found for non-athletes (p = 0.04) and long-term supplementation (p = 0.02) in performance tests, as well as non-athletes (p = 0.005) in performance tests and long-term supplementation (p = 0.006) in exercise tolerance. The nonsignificant results were likely due to the limitation in the number of related papers, sample sizes, optimal dosage, duration, type of flavonoids, and other factors. Therefore, future research should focus on further investigating these relationships with larger sample sizes, optimal dosage, duration, and type of flavonoids to provide more robust conclusions.

Biomarkers of sustained systemic inflammation and microvascular dysfunction associated with post-COVID-19 condition symptoms at 24 months after SARS-CoV-2-infection

Introduction

Comprehensive studies investigating sustained hypercoagulability, endothelial function, and/or inflammation in relation to post-COVID-19 (PCC) symptoms with a prolonged follow-up are currently lacking. Therefore, the aim of this single-centre cohort study was to investigate serum biomarkers of coagulation activation, microvascular dysfunction, and inflammation in relation to persisting symptoms two years after acute COVID-19.

Methods

Patients diagnosed with acute SARS-CoV-2 infection between February and June 2020 were recruited. Outcome measures included the CORona Follow-Up (CORFU) questionnaire, which is based on an internationally developed and partially validated basic questionnaire on persistent PCC symptoms. Additionally, plasma biomarkers reflecting coagulation activation, endothelial dysfunction and systemic inflammation were measured.

Results

167 individuals were approached of which 148 (89%) completed the CORFU questionnaire. At 24 months after acute infection, fatigue was the most prevalent PCC symptom (84.5%). Over 50% of the patients experienced symptoms related to breathing, cognition, sleep or mobility; 30.3% still experienced at least one severe or extreme (4 or 5 on a 5-point scale) PCC symptom. Multiple correlations were found between several PCC symptoms and markers of endothelial dysfunction (endothelin-1 and von Willebrand factor) and systemic inflammation (Interleukin-1 Receptor antagonist). No positive correlations were found between PCC symptoms and coagulation complexes.

Discussion

In conclusion, this study shows that at 24 months after acute COVID-19 infection patients experience a high prevalence of PCC symptoms which correlate with inflammatory cytokine IL-1Ra and markers of endothelial dysfunction, especially endothelin-1. Our data may provide a rationale for the selection of treatment strategies for further clinical studies.

Trial registration

This study was performed in collaboration with the CORona Follow-Up (CORFU) study (NCT05240742, https://clinicaltrials.gov/ct2/show/ NCT05240742).

Sarcopenia, a condition shared by various diseases: can we alleviate or delay the progression?

Sarcopenia is a severe condition common to various chronic diseases and it is reckoned as a major health problem. It encompasses many different molecular mechanisms that have been for a while discovered but not definitely clarified. Although sarcopenia is a disability status that leads to serious health consequences, the scarcity of suitable animal models has curtailed research addressing this disorder. Another limitation in the field of clinical investigation of sarcopenic patients is the lack of a generally accepted definition coupled with the difficulty of adopting common diagnostic criteria. In fact, both do not permit to clarify the exact prevalence rate and consequently limit physicians to establish any kind of therapeutical approach or, when possible, to adopt preventive measures. Unfortunately, there is no standardized cure, apart from doing more physical activity and embracing a balanced diet, but newly discovered substances start being considered. In this review, authors try to give an overview addressing principal pathways of sarcopenia and offer critical features of various possible interventions.

New Horizons: Testosterone or Exercise for Cardiometabolic Health in Older Men

Middle-aged and older men have typically accumulated comorbidities, are increasingly sedentary, and have lower testosterone concentrations (T) compared to younger men. Reduced physical activity (PA) and lower T both are associated with, and may predispose to, metabolically adverse changes in body composition, which contribute to higher risks of cardiometabolic disease. Exercise improves cardiometabolic health, but sustained participation is problematic. By contrast, rates of T prescription have increased, particularly in middle-aged and older men without organic diseases of the hypothalamus, pituitary, or testes, reflecting the unproven concept of a restorative hormone that preserves health. Two recent large randomized trials of T, and meta-analyses of randomized trials, did not show a signal for adverse cardiovascular (CV) events, and T treatment on a background of lifestyle intervention reduced type 2 diabetes by 40% in men at high risk. Men with both higher endogenous T and higher PA levels have lower CV risk, but causality remains unproven. Exercise training interventions improve blood pressure and endothelial function in middle-aged and older men, without comparable benefits or additive effects of T treatment. Therefore, exercise training improves cardiometabolic health in middle-aged and older men when effectively applied as a supervised regimen incorporating aerobic and resistance modalities. Treatment with T may have indirect cardiometabolic benefits, mediated via favorable changes in body composition. Further evaluation of T as a pharmacological intervention to improve cardiometabolic health in aging men could consider longer treatment durations and combination with targeted exercise programs.

Arterial Structure in 18-Year-Old Males Is Dependent on Physical Activity at 12 Years and Cumulative Cardiorespiratory Fitness From Puberty to Late Adolescence

PURPOSE

To evaluate the long-term effect of body composition, physical activity, and cardiorespiratory fitness (CRF) from puberty on arterial health in late adolescent males.

METHODS

The cumulative burden of physical activity (measured with accelerometer), CRF (VO2peak0.82), and body composition (body mass index, fat mass, and fat percentage) from puberty to late adolescence (sum of 4 time points from 12 to 18 y) was assessed in 102 males. Additional analysis on the first (T1) and last (T4) time points was performed. Intima-media thickness (IMT), carotid-femoral pulse wave velocity, and augmentation index adjusted to heart rate of 75 beats per minute (bpm) as dependent variables were measured at T4 and analyzed in multivariable regression models adjusted for known risk factors including maturation, blood pressure, and smoking habits.

RESULTS

T1 and cumulative body composition measures were independently associated with IMT, while cumulative (β = -0.011, P = .036) and T4 (β = -0.0.031, P = .001) CRF revealed independent associations with IMT. Individuals with moderate to vigorous physical activity >60 minutes per day at T1 showed relationship (β = -1.091, P = .026) with IMT independently of late adolescent physical activity. No significant relationship was present for arterial function.

CONCLUSION

Arterial structure in adolescent males is associated with physical activity at 12 years while relationship with CRF can be seen in late adolescence and cumulatively from puberty to late adolescence.

Cardiometabolic Profile, Physical Activity, and Quality of Life in Breast Cancer Survivors after Different Physical Exercise Protocols: A 34-Month Follow-Up Study

BACKGROUND

Breast cancer (BC) and cardiovascular (CV) disease share many risk factors associated with worse outcomes, in terms of cancer relapse, CV events, and quality of life (QoL), that could be counteracted by physical exercise (PE). We aimed to assess the impact of a 12-week differential PE protocol on cardiometabolic profile, QoL, CV- and BC-related long-term outcomes, and physical activity (PA) in a cohort of BC survivors (BCS) not treated with chemotherapy.

METHODS

57 BCS participated in a 12-week PE protocol [aerobic exercise training (AET) or resistance exercise training (RET)]. Anthropometric and CV evaluation, health-related (HR)-QoL, daily PA, cortisol, and dehydroepiandrosterone sulfate (DHEA-S) levels were assessed before (T0) and after (T1) PE. We assessed BC and CV outcomes, HR-QoL, CV-QoL, and PA at the follow-up.

RESULTS

RET improved waist circumference, DHEA-S, cortisol/DHEA-S, systolic and mean blood pressure, and ventricular/arterial coupling; AET ameliorated sagittal abdomen diameter and pulse wave velocity. Regarding HR-QoL, physical function improved only in AET group. At a mean 34 ± 3.6-month follow-up, we documented no significant differences in CV-QoL, HR-QoL, and PA or CV and BC outcomes.

CONCLUSIONS

AET and RET determine specific, positive adaptations on many parameters strongly related to CV risk, CV and BC outcomes, and QoL, and should be included in any cardio-oncology rehabilitation program.

Exercise and Experiments of Nature

In this article, we highlight the contributions of passive experiments that address important exercise-related questions in integrative physiology and medicine. Passive experiments differ from active experiments in that passive experiments involve limited or no active intervention to generate observations and test hypotheses. Experiments of nature and natural experiments are two types of passive experiments. Experiments of nature include research participants with rare genetic or acquired conditions that facilitate exploration of specific physiological mechanisms. In this way, experiments of nature are parallel to classical "knockout" animal models among human research participants. Natural experiments are gleaned from data sets that allow population-based questions to be addressed. An advantage of both types of passive experiments is that more extreme and/or prolonged exposures to physiological and behavioral stimuli are possible in humans. In this article, we discuss a number of key passive experiments that have generated foundational medical knowledge or mechanistic physiological insights related to exercise. Both natural experiments and experiments of nature will be essential to generate and test hypotheses about the limits of human adaptability to stressors like exercise. © 2023 American Physiological Society. Compr Physiol 13:4879-4907, 2023.

Crossover point and maximal fat oxidation training effects on blood lipid metabolism in young overweight women: a pilot study

Purpose: To determine the effects of weight reduction schemes using the exercise intensities corresponding to maximal fat oxidation (FATmax) and crossover point (COP). The effects of different intervention protocols on blood lipid metabolism were compared to explore how fat can be consumed and used more efficiently and provide a theoretical basis for weight loss through exercise. Methods: This study included 30 young overweight women randomly divided into the COP, FATmax, and control groups. Participants in the COP and FATmax groups exercised for 45 min four times a week for 8 weeks after the individual treadmill exercise test. The control group did not perform any exercise. Results: After 8 weeks of training, participants in the COP group significantly decreased weight (2.6 ± 3.3 kg), body mass index (0.91 ± 1.26 kg/m²), body fat percentage (1.21% ± 1.50%), and fat mass (1.90 ± 2.30 kg) (p < 0.05). They also had significantly decreased hip circumference (4.8 ± 3.3 cm), serum apolipoprotein B (ApoB) levels (15.48 ± 14.19 mg/dL), and ApoB/apolipoprotein AI (ApoAI) ratios (0.47 ± 0.37) (p < 0.01). However, their serum ApoAI levels were significantly increased (14.18 ± 10.24 mg/dL; p < 0.01). Participants in the FATmax group had significantly decreased hip circumference (2.4 ± 2.0 cm), serum ApoB levels (14.49 ± 11.00 mg/dL), and ApoB/ApoAI ratios (0.59 ± 0.30) (p < 0.01) but significantly increased serum ApoAI levels (29.53 ± 13.29 mg/dL; p < 0.01). No significant changes in physiological indexes were observed in participants in the control group. Conclusion: Personalised exercise intervention positively affected central obesity, effectively improving blood lipid metabolism and fat oxidation, reducing cardiovascular disease risk in young overweight women. COP training improved weight and body composition better than the FATmax exercise, while the latter provided greater improvements in serum ApoAI levels.

Effects of a Mobile-Health Exercise Intervention on Body Composition, Vascular Function, and Autonomic Nervous System Function in Obese Women: A Randomized Controlled Trial

Purpose

The present study verified the effect of an m-health exercise intervention using a 12-week exercise program on body composition, vascular function, and the ANS.

Patients and Methods

Thirty obese adult women participants were randomized (n = 15 each) into the experimental (EXP) group, those who performed mobile-health (m-health) exercises using a wearable device (Charge 4, Fitbit, USA) and AI-fit web page, or the control (CON) group, those who continued their daily activities as before. Muscle function, cardiorespiratory endurance, and flexibility were assessed during the exercise program using the AI-fit web page and wearable device. The EXP group participated in exercise interventions using the m-health system for 12 weeks, while the CON group was encouraged to maintain their normal daily routines. Body composition, vascular function, and autonomic nervous system (ANS) were evaluated before and after the intervention.

Results

Significant decreases were noted in fat mass (Post - Pre: -1.47 kg; p < 0.001) and percent body fat (Post - Pre: -2.11%; p < 0.05). Flow-mediated dilatation (Post - Pre: 2.63%; p < 0.001) was significantly increased, and brachial-ankle pulse wave velocity (Post - Pre: -91.49 cm·sec^-1; p < 0.01) was significantly decreased. RMSSD (Post - Pre: 10.43 ms; p < 0.01), NN50 (Post-Pre: 24.04; p < 0.05), pNN50 (Post - Pre: 7.70%; p < 0.05) and HF (Post-Pre: 179.60 ms²; p < 0.05) increased significantly.

Conclusion

In conclusion, m-health exercise interventions using AI fit and wearable devices are effective in preventing obesity and improving vascular function, and ANS.

Acute Effects of New Zealand Blackcurrant Extract on Cycling Time-Trial Are Performance Dependent in Endurance-Trained Cyclists: A Home-Based Study

The intake of anthocyanin-rich New Zealand blackcurrant (NZBC) extract (300 mg per day) over a week enhanced 16.1 km cycling time trial (TT) performance in endurance-trained cyclists without acute performance effects. In the present study, the acute effects of an intake of 900 mg of NZBC extract 2 h before performing the 16.1 km cycling TT were examined. A total of 34 cyclists (26 males; 8 females) (age: 38 ± 7 years, V˙O_2max: 57 ± 5 mL·kg^-1·min^-1) completed 4 16.1 km TTs (2 familiarization and 2 experimental trials) over 4 mornings on a home turbo-trainer connected with the online training simulator ZWIFT. There was no difference in time to complete the 16.1 km TT between conditions (placebo: 1422 ± 104 s; NZBC extract: 1414 ± 93 s, p = 0.07). However, when participants were split between faster (<1400 s; 1 female; 16 males) and slower (>1400 s; 7 females; 10 males) cyclists based on average familiarization TTs, a difference in TT performance was observed only in the slower group (placebo: 1499 ± 91 s; NZBC extract: 1479 ± 83 s, p = 0.02). At 12 km (quartile analysis), power output (p = 0.04) and speed (p = 0.04) were higher compared to the placebo with no effects on heart rate and cadence. The acute effects of 900 mg of NZBC extract on a 16.1 km cycling time-trial may depend on the performance ability of male endurance-trained cyclists. More work is needed to address whether there is a sex-specific time-trial effect of NZBC extract independent of performance ability.

Androgen-Induced Cardiovascular Risk in Polycystic Ovary Syndrome: The Role of T Lymphocytes

An estimated 15-20% of reproductive-age women are affected by polycystic ovary syndrome (PCOS). PCOS is associated with substantial metabolic and cardiovascular long-term consequences. In young women with PCOS, several cardiovascular risk factors may be found, including chronic inflammation, high blood pressure, and elevated leukocytes. These women are at an increased risk of cardiovascular diseases (CVD), not only during the reproductive years, but also with aging and menopause; therefore, the early prevention and treatment of future cardiovascular adverse effects are necessary. The fundamental characteristic of PCOS is hyperandrogenemia, which is associated with increased pro-inflammatory cytokines and T lymphocytes. Whether these factors play a role in the pathophysiology of hypertension, a risk factor of CVD, due to PCOS is not well established. This review will briefly discuss how a modest increase in androgens in females is linked to the development of hypertension through pro-inflammatory cytokines and T lymphocyte subsets and the promotion of renal injury. Moreover, it reveals a few existing research gaps in this area, including the lack of specific therapy directed at androgen-induced inflammation and immune activation, thus emphasizing the necessity to explore the systemic inflammation in women with PCOS to halt the inevitable inflammatory process targeting the underlying abnormalities of CVD.

Effects of gypenoside L-containing Gynostemma pentaphyllum extract on fatigue and physical performance: A double-blind, placebo-controlled, randomized trial

This study was conducted to investigate the effect of Gynostemma pentaphyllum extract containing gypenoside L (GPE) on improving the cognitive aspects of fatigue and performance of the motor system. One hundred healthy Korean adults aged 19-60 years were randomized to the treatment (GPE for 12 weeks) and control groups, and efficacy and safety-related parameters were compared between the two groups. Maximal oxygen consumption (VO₂ max) and O₂ pulse were significantly higher in the treatment group than in the control group (p = 0.007 and p = 0.047, respectively). After 12 weeks, the treatment group showed significant changes such as decreases in the levels of free fatty acids (p = 0.042). In addition, there were significant differences in the rating of perceived exertion (RPE) (p < 0.05) and value of temporal fatigue between the treatment and control groups on the multidimensional fatigue scale (p < 0.05). Moreover, the level of endothelial nitric oxide synthase (eNOS) in the blood was significantly higher in the treatment group than in the control group (p = 0.047). In summary, oral administration of GPE has a positive effect on resistance to exercise-induced physical and mental fatigue.

Oxidative stress, inflammation and hormesis: The role of dietary and lifestyle modifications on aging

Oxidative stress (OS) is primarily caused by the formation of free radicals and reactive oxygen species; it is considered as one of the prominent factors in slowing down and degrading cellular machinery of an individual, and it eventually leads to aging and age-related diseases by its continuous higher state. The relation between molecular damage and OS should be particularized to understand the beginning of destruction at the cellular levels, extending outwards to affect tissues, organs, and ultimately to the organism. Several OS biomarkers, which are established at the biomolecular level, are useful in investigating the disease susceptibility during aging. Slowing down the aging process is a matter of reducing the rate of oxidative damage to the cellular machinery over time. The breakdown of homeostasis, the mild overcompensation, the reestablishment of homeostasis, and the adaptive nature of the process are the essential features of hormesis, which incorporates several factors, including calorie restriction, nutrition and lifestyle modifications that play an important role in reducing the OS. In the current review, along with the concept and theories of aging (with emphasis on free radical theory), various manifestations of OS with special attention on mitochondrial dysfunction and age-related diseases have been discussed. To alleviate the OS, hormetic approaches including caloric restriction, exercise, and nutrition have also been discussed.

Clinical trials in mitochondrial diseases

Primary mitochondrial diseases are some of the most common and complex inherited inborn errors of metabolism. Their molecular and phenotypic diversity has led to difficulties in finding disease-modifying therapies and clinical trial efforts have been slow due to multiple significant challenges. Lack of robust natural history data, difficulties in finding specific biomarkers, absence of well-validated outcome measures, and small patient numbers have made clinical trial design and conduct difficult. Encouragingly, new interest in treating mitochondrial dysfunction in common diseases and regulatory incentives to develop therapies for rare conditions have led to significant interest and efforts to develop drugs for primary mitochondrial diseases. Here, we review past and present clinical trials and future strategies of drug development in primary mitochondrial diseases.

Effect of continuous aerobic exercise on endothelial function: A systematic review and meta-analysis of randomized controlled trials

Background: Current research suggests that continuous aerobic exercise can be effective in improving vascular endothelial function, while the effect between different intensities and durations of exercise is unclear. The aim of this study was to explore the effect of different durations and intensities of aerobic exercise on vascular endothelial function in different populations. Methods: Searches were performed in PubMed, Web of Science, and EBSCO databases. We included studies that satisfied the following criteria: 1) randomized controlled trials (RCTs); 2) including both an intervention and control group; 3) using flow-mediated dilation (FMD) as the outcome measure; and 4) testing FMD on the brachial artery. Results: From 3,368 search records initially identified, 41 studies were eligible for meta-analysis. There was a significant effect of continuous aerobic exercise on improving flow-mediated dilation (FMD) [weighted mean difference (WMD), 2.55, (95% CI, 1.93-3.16), p < 0.001]. Specifically, moderate-intensity [2.92 (2.02-3.825), p < 0.001] and vigorous-intensity exercise [2.58 (1.64-3.53), p < 0.001] significantly increased FMD. In addition, a longer duration [<12 weeks, 2.25 (1.54-2.95), p < 0.001; ≥12 weeks, 2.74 (1.95-3.54), p < 0.001], an older age [age <45, 2.09 (0.78-3.40), p = 0.002; 45 ≤ age <60, 2.25 (1.49-3.01), p < 0.001; age ≥60, 2.62 (1.31-3.94), p < 0.001], a larger basal body mass index (BMI) [20 < BMI < 25, 1.43 (0.98-1.88), p < 0.001; 25 ≤ BMI < 30, 2.49 (1.07-3.90), p < 0.001; BMI ≥ 30, 3.05 (1.69-4.42), p < 0.001], and a worse basal FMD [FMD < 4, 2.71 (0.92-4.49), p = 0.003; 4 ≤ FMD < 7, 2.63 (2.03-3.23), p < 0.001] were associated with larger improvements in FMD. Conclusion: Continuous aerobic exercise, especially moderate-intensity and vigorous-intensity aerobic exercise, contributed to improving FMD. The effect of continuous aerobic exercise on improving FMD was associated with duration and participant's characteristics. Specifically, a longer duration, an older age, a larger basal BMI, and a worse basal FMD contributed to more significant improvements in FMD. Systematic Review Registration: [https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=341442], identifier [CRD42022341442].

Effect of exercise on vascular function in hypertension patients: A meta-analysis of randomized controlled trials

Objective

The purpose of this study was to systematically evaluate the effect of exercise on vascular function in patients with pre- and hypertension.

Methods

A systematic review of articles retrieved via the PubMed, Embase, EBSCO, and Web of Science databases was conducted. All the randomized controlled trials published between the establishment of the databases and October 2022 were included. Studies that evaluated the effects of exercise intervention on vascular function in patients with pre- and hypertension were selected.

Results

A total of 717 subjects were included in 12 randomized controlled trials. The meta-analysis showed that in patients with pre- and hypertension, exercise can significantly reduce systolic blood pressure (SBP) (MD = -4.89; 95% CI, -7.05 to -2.73; P < 0.00001) and diastolic blood pressure (DBP) (MD = -3.74; 95% CI, -5.18 to -2.29; P < 0.00001) and can improve endothelium-dependent flow-mediated dilatation (MD = 2.14; 95% CI, 1.71-2.61; P < 0.00001), and exercise did not reduce pulse wave velocity (PWV) (MD = 0.03, 95% CI, -0.45-0.50; P = 0.92). Regression analysis showed that changes in exercise-related vascular function were independent of subject medication status, baseline SBP, age and duration of intervention.

Conclusion

Aerobic, resistance, and high-intensity intermittent exercise all significantly improved SBP, DBP, and FMD in pre- and hypertensive patients, however, they were not effective in reducing PWV, and this effect was independent of the subject's medication status, baseline SBP, age and duration of intervention.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022302646.

Effects of Acute and Chronic Exercise in Hypoxia on Cardiovascular and Glycemic Parameters in Patients with Type 2 Diabetes: A Systematic Review

Kindlovits, Raquel, Alberto Mello da Silva Pereira, Ana Catarina Sousa, João Luís Viana,and Vitor Hugo Teixeira. Effects of acute and chronic exercise in hypoxia on cardiovascular and glycemic parameters in patients with type 2 diabetes: a systematic review. High Alt Med Biol. 23:301-312, 2022. Background: Exercise in hypoxia (EH, decreased oxygen availability) has been proposed as a potential therapeutic intervention to promote angiogenesis and improve glucose metabolism to a greater extent than exercise under normoxia (normal ambient air) in patients with type 2 diabetes (T2D). Currently, there are no studies that systematize the existent evidence. This study aims to systematically review the literature and qualitatively evaluate the effects of acute and chronic EH on cardiovascular and glycemic parameters in T2D patients. Methods: A structured search was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines until March 2021, in the MEDLINE/PubMed, Scopus, and Web of Science databases. The inclusion criteria were as follows: (1) randomized and nonrandomized trials, (2) in complication-free patients with T2D, (3) in which EH was compared with exercise in normoxia or with baseline data, and (4) published in English. Results: Six articles (64 subjects) met the inclusion criteria and were reviewed to data extraction. Four articles investigated the acute effect of EH (33 subjects), and two articles investigated the chronic effect of EH (31 subjects), ranging from 6 to 8 weeks. All studies used a cycle ergometer as exercise. Acute EH benefits insulin sensitivity, blood glucose, vascular endothelial growth factor, and metalloproteinase-9, while chronic EH benefits nitric oxide synthase in erythrocytes, but not brachial artery flow-mediated dilation. Conclusion: Acute EH improves glucose homeostasis in T2D patients, which was not seen with chronic EH. Both acute EH and chronic EH improve angiogenesis regulators, but not vascular function. Despite the putative benefits of EH in patients with T2D, the evidence is still scarce and further research is needed before recommendations can be provided.

Atherosclerosis Prevention in Adolescents with Obesity: The Role of Moderate-Vigorous Physical Activity

Carotid intima-media thickness (cIMT) is a subclinical marker of atherosclerotic development, which is impaired in adolescents with obesity. This study aimed to analyze the impact of physical activity (PA), cardiorespiratory fitness (CRF), body mass index (BMI), and body composition changes on the cIMT of adolescents with obesity. Longitudinal data (6 months) from adolescents aged 12-18 years, with a BMI ≥97th percentile, previously recruited for the non-randomized controlled trial PAC-MAnO (Clinicaltrials.gov-NCT02941770) were analyzed using partial correlations controlling for sex and pubertal status and multiple regressions. A total of 105 adolescents (51.4% girls, 86.7% Caucasian), 14.8 ± 1.8 years old, with a BMI z-score of 3.09 ± 0.74 were included. Total body fat mass (TBFM) (F(1,91) = 23.11, p < 0.001), moderate-vigorous PA (MVPA) (F(1,91) = 7.93, p = 0.0006), and CRF (mL/kg/min) (F(1,90) = 19.18, p < 0.001) predicted cIMT variance with an R² of 0.24, 0.09, and 0.23, respectively. MVPA changes showed a high correlation with CRF variation (r(91) = 0.0661, p < 0.001). This study suggests that although cIMT is impaired in overweight adolescents, improvements in TBFM, MVPA, and CRF are associated with cIMT improvement. Although both energy intake and MVPA may influence TBFM, MVPA plays the most relevant role in cIMT development due to its direct association with CRF.

Positive effect of total knee arthroplasty on progression of arteriosclerosis evaluated by cardio-ankle vascular index

INTRODUCTION

Physical function is expected to improve with an increase in physical activity owing to improvement in knee joint pain after total knee arthroplasty (TKA). This study was performed to evaluate the impact of TKA on arteriosclerosis by measuring the cardio-ankle vascular index (CAVI) before and after surgery.

MATERIALS AND METHODS

In total, 206 consecutive patients undergoing unilateral TKA were investigated. The CAVI, an index of the overall stiffness of the artery from the origin of the aorta to the ankle, was used to evaluate the degree of arteriosclerosis. The CAVI of the TKA side and non-TKA side was compared before and 1 year after TKA.

RESULTS

There were no differences in the CAVI before and after TKA on the TKA side and non-TKA side, although these values should have worsened at 1 year compared with preoperative values. The CAVI, which did not differ between the two sides preoperatively, differed significantly between the two sides postoperatively (p = 0.013). A generalized linear model showed no interaction between each time point and the measured sides in terms of the CAVI. The relationship between the preoperative CAVI and the difference between the preoperative and postoperative CAVI were examined, showing that R =  - 0.428 (p < 0.001) for the TKA side and R =  - 0.416 (p < 0.001) for the non-TKA side (significant negative correlation).

CONCLUSIONS

The lack of significant age-related deterioration over time on both sides suggests that TKA may slow the progression of arteriosclerosis, especially on the operated side. The effect of TKA was found to be greater with a higher CAVI (i.e., more advanced arteriosclerosis).

Effect of Lower- versus Higher-Intensity Isometric Handgrip Training in Adults with Hypertension: A Randomized Controlled Trial

This study compared the effects of lower- versus higher-intensity isometric handgrip exercise on resting blood pressure (BP) and associated clinical markers in adults with hypertension. Thirty-nine males were randomly assigned to one of three groups, including isometric handgrip at 60% maximal voluntary contraction (IHG-60), isometric handgrip at 30% IHG-30, or a control group (CON) that had been instructed to continue with their current activities of daily living. The volume was equated between the exercise groups, with IHG-60 performing 8 × 30-s contractions and IHG-30 performing 4 × 2-min contractions. Training was performed three times per week for 8 weeks. Resting BP (median [IQR]), flow-mediated dilation, heart rate variability, and serum markers of inflammation and oxidative stress were measured pre- and post-intervention. Systolic BP was significantly reduced for IHG-60 (−15.5 mmHg [−18.75, −7.25]) and IHG-30 (−5.0 mmHg [−7.5, −3.5]) compared to CON (p < 0.01), but no differences were observed between both the exercise groups. A greater reduction in diastolic BP was observed for IHG-60 (−5.0 mmHg [−6.0, −4.25] compared to IHG-30 (−2.0 mmHg [−2.5, −2.0], p = 0.042), and for both exercise groups compared to CON (p < 0.05). Flow-mediated dilation increased for both exercise groups versus CON (p < 0.001). IHG-30 had greater reductions in interleukin-6 and tumor necrosis factor-α compared to the other groups (p < 0.05) and CON (p = 0.018), respectively. There was a reduction in Endothelin-1 for IHG-60 compared to CON (p = 0.018). Both the lower- and higher-intensity IHG training appear to be associated with reductions in resting BP and improvements in clinical markers of inflammation and oxidative stress.

Effects of aerobic, resistance, and combined training on endothelial function and arterial stiffness in older adults: study protocol for a systematic review and meta-analysis

INTRODUCTION

Aging is an independent risk factor for cardiovascular events. It promotes vascular dysfunction which is associated with risk factors for cardiovascular diseases (CVDs). Exercise can modulate vascular function parameters, but little is known about the effects of different modalities of training (aerobic, resistance, and combined) on endothelial function and arterial stiffness in older adults.

METHODS

This systematic review study will include randomized controlled trials (RCTs) selected from the electronic databases MEDLINE (PubMed), Cochrane, LILACS, EMBASE, and Web of Science. We will follow the PRISMA guidelines and PICOS framework. Studies involving both male and female older adults (≥60 years old) with or without comorbidities undergoing aerobic, resistance, and/or combined training compared to a control group (no exercise) will be eligible. We will use the Cochrane Risk of Bias 2 (RoB 2) tool to evaluate the quality of individual studies and GRADE to assess the strength of evidence. Statistical analyses will be conducted with RStudio for Windows (v1.3.959) using R package meta.

DISCUSSION

A systematic review and meta-analysis involving data from studies of older adults would deepen our understanding of vascular adaptations to exercise training in this population. It could provide new insights into how health providers can improve patient management and prevention of cardiovascular events in older adults.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO 42021275451.

Efficacy of interval exercise training to improve vascular health in sedentary postmenopausal females

BACKGROUND

Menopause represents a turning point where vascular damage begins to outweigh reparative processes, leading to increased cardiovascular disease (CVD) risk. Exercise training reduces CVD risk in postmenopausal females via improvements in traditional risk factors and direct changes to the vasculature. We assessed the effect of moderate (MODERATE-IT) versus heavy (HEAVY-IT) intensity interval exercise training upon markers of cardiovascular health and vascular repair in postmenopausal females.

METHODS

Twenty-seven healthy postmenopausal females (56 ± 4 yr) were assigned to 12 weeks of either MODERATE-IT or HEAVY-IT, twice per week. MODERATE-IT consisted of 10s work, and 10s active recovery repeated for 30 min. HEAVY-IT comprised 30s work, and 30s active recovery repeated for 21 ± 2 min. Endothelial function (flow-mediated dilation), arterial stiffness (pulse wave velocity), and V̇O_2peak were assessed pre-training and post-training. Blood samples were obtained pre-training and post-training for enumeration of circulating angiogenic cells (CACs), culture of CACs, and lipoprotein profile.

RESULTS

V̇O_2peak increased 2.4 ± 2.8 ml/kg/min following HEAVY-IT only (p < 0.05). Brachial blood pressure and endothelial function were unchanged with exercise training (p > 0.05). Peripheral pulse wave velocity reduced 8% with exercise training, irrespective of intensity (p < 0.05). Exercise training had no effect on lipoprotein profile or endothelin-1 (p > 0.05). CAC adhesion to vascular smooth muscle cells (VSMC) increased 30 min post plating following MODERATE-IT only (p < 0.05).

CONCLUSIONS

HEAVY-IT was more effective at increasing V̇O_2peak in postmenopausal females. The ability of CACs to adhere to VSMC improved following MODERATE-IT but not HEAVY-IT. Interval training had the same effect on endothelial function (no change) and arterial stiffness (reduced), regardless of exercise intensity.

The effects of a motorized passive simulated jogging device on descent of the arterial pulse waveform dicrotic notch: A single arm placebo-controlled cross-over trial

Whole Body Periodic Acceleration (WBPA, pGz), is a bed that moves the body headward to forward, adds pulses to the circulation inducing descent of the dicrotic notch (DN) on the pulse waveform with an increase in a/b ratio (a = the height of the pulse waveform and b = the height of the secondary wave). Since the WBPA is large, heavy, and non-portable, we engineered a portable device (Jogging Device, JD). JD simulates passive jogging and introduces pulsations to the circulation. We hypothesized that JD would increase the a/b ratio during and after its use. In Study A, a single-arm placebo-controlled cross-over trial was conducted in24 adults (53.8 ± 14.4 years) using JD or control (CONT) for 30 min. Blood pressure (BPs and BPd) and photoplethysmograph pulse (a/b) were measured at baseline (BL), during 30 min of JD or CONT, and 5 and 60 min after. In Study B (n = 20, 52.2 ± 7 years), a single-arm observational trial of 7 consecutive days of JD on BP and a/b, measured at BL, and after 7 days of JD and 48 and 72 hr after its discontinuation. In Study A, BPs, and BPd decreased during JD by 13% and 16%, respectively, while in CONT both increased by 2% and 2.5%, respectively. The a/b increased by 2-fold and remained greater than 2-fold at all-time points, with no change in a/b during CONT. In Study B, BPs and BPd decreased by 9% and remained below BL, at 72 hr after discontinuation of JD. DN descent also occurred after 7 days of JD with a/b increase of 80% and remained elevated by 60% for at least 72 h. JD improves acute and longer-term vascular hemodynamics with an increase in a/b, consistent with increased effects of nitric oxide (NO). JD may have significant clinical and public health implications.

Nitric Oxide Involvement in Cardiovascular Dysfunctions of Parkinson Disease

Parkinson’s disease (PD) is characterized by the loss of dopaminergic neurons in the substantia nigra, causing motor changes. In addition to motor symptoms, non-motor dysfunctions such as psychological, sensory and autonomic disorders are recorded. Manifestations related to the autonomic nervous system include the cardiovascular system, as postural hypotension, postprandial hypotension, and low blood pressure. One of the mediators involved is the nitric oxide (NO). In addition to the known roles such as vasodilator, neuromodulator, NO acts as an important mediator of the immune response, increasing the inflammatory response provoked by PD in central nervous system. The use of non-specific NOS inhibitors attenuated the neurodegenerative response in animal models of PD. However, the mechanisms by which NO contributes to neurodegeneration are still not well understood. The literature suggest that the contribution of NO occurs through its interaction with superoxides, products of oxidative stress, and blocking of the mitochondrial respiratory chain, resulting in neuronal death. Most studies involving Parkinsonism models have evaluated brain NO concentrations, with little data available on its peripheral action. Considering that studies that evaluated the involvement of NO in the neurodegeneration in PD, through NOS inhibitors administration, showed neuroprotection in rats, it has prompted new studies to assess the participation of NOS isoforms in cardiovascular changes induced by parkinsonism, and thus to envision new targets for the treatment of cardiovascular disorders in PD. The aim of this study was to conduct a literature review to assess available information on the involvement of nitric oxide (NO) in cardiovascular aspects of PD.

Aerobic Exercise Attenuates Kidney Injury, Improves Physical Performance, and Increases Antioxidant Defenses in Lungs of Adenine-Induced Chronic Kidney Disease Mice

The association between chronic kidney disease (CKD) and pulmonary pathophysiological changes is well stablished. Nevertheless, the effects of aerobic exercise (AE) on lungs of CKD need further clarification. Thus, Swiss mice were divided in control, AE, CKD, and CKD + AE groups. CKD was induced by 0.2% adenine intake during 8 weeks (4 weeks of CKD induction and 4 weeks of AE). AE consisted in running on treadmill, at moderate intensity, 30 min/day, 5 days/week, during 4 weeks. Twenty-four hours after the last training day, functional capacity test was performed, and 48 h after the test, mice were euthanized. CKD mice showed a significant increase in urine output, serum urea, and creatinine concentrations, and decreased body weight and urine density, besides oxidative damage (p = 0.044), edema area (p < 0.001), leukocyte infiltration (p = 0.040), and collagen area in lung tissue (p = 0.004). AE resulted in an increase of distance traveled (p = 0.049) and maximum speed (p = 0.046), increased activity of catalase (p = 0.031) and glutathione peroxidase (p = 0.048) in lungs, increased levels of nitric oxide (NOx) in serum (p = 0.001) and bronchoalveolar lavage fluid (p = 0.047), and decreased kidney histological injury (p = 0.018) of CKD mice. However, AE also increased oxidative damage (p = 0.003) and did not change collagen content or perivascular edema in lungs (p > 0.05) of CKD mice. Therefore, AE attenuated kidney injury and improved antioxidants defenses in lungs. Despite no significant changes in pulmonary damage, AE significantly improved physical performance in CKD mice.

Cardiac Rehabilitation Improves Endothelial Function in Coronary Artery Disease Patients

Exercise-based cardiac rehabilitation may be an effective non-pharmacological intervention for improving endothelial function in coronary artery disease patients. Therefore, this systematic review with meta-analysis aimed to (a) estimate the training-induced effect on endothelial and vascular smooth muscle function, assessed by flow-mediated dilation and nitroglycerin-mediated dilation, respectively, in coronary artery disease patients; and to (b) study the influence of potential trial-level variables (i. e. study and intervention characteristics) on the training-induced effect on endothelial and vascular smooth muscle function. Electronic searches were performed in Pubmed, Scopus, and Embase up to February 2021. Random-effects models of standardised mean change were estimated. Heterogeneity analyses were performed by using the Chi ² test and I ² index. Our results showed that exercise-based cardiac rehabilitation significantly enhanced flow-mediated dilation (1.04 [95% confidence interval=0.76 to 1.31]) but did not significantly change nitroglycerin-mediated dilation (0.05 [95% confidence interval=-0.03 to 0.13]). Heterogeneity testing reached statistical significance (p<.001) with high inconsistency for flow-mediated dilation (I ² =92%). Nevertheless, none of the analysed variables influenced the training-induced effect on flow-mediated dilation. Exercise-based cardiac rehabilitation seems to be an effective therapeutic strategy for improving endothelial-dependent dilation in coronary artery disease patients, which may aid in the prevention of cardiovascular events.

Moderate-Intensity Exercise Training Reduces Vasorelaxation of Mesenteric Arteries: Role of BKCa Channels and Nitric Oxide

Exercise training (ET) is well established to induce vascular adaptations on the metabolically active muscles. These adaptations include increased function of vascular potassium channels and enhanced endothelium-dependent relaxations. However, the available data on the effect of ET on vasculatures that normally constrict during exercise, such as mesenteric arteries (MA), are scarce and not conclusive. Therefore, this study hypothesized that 10 weeks of moderate-intensity ET would result in adaptations towards more vasoconstriction or/and less vasodilatation of MA. Young Fischer 344 rats were randomly assigned to a sedentary group (SED; n=24) or exercise training group (EXE; n=28). The EXE rats underwent a progressive treadmill ET program for 10 weeks. Isometric tensions of small (SED; 252.9±29.5 µm, EXE; 248.6±34.4 µm) and large (SED; 397.7±85.3 µm, EXE; 414.0±86.95 µm) MA were recorded in response to cumulative phenylephrine concentrations (PE; 0-30 µM) in the presence and absence of the BKCa channel blocker, Iberiotoxin (100 nM). In another set of experiments, tensions in response to cumulative concentration-response curves of acetylcholine (ACh) or sodium nitroprusside (SNP) were obtained, and pEC50s were compared. Immunoblotting was performed to measure protein expression levels of the BKCa channel subunits and eNOS. ET did not alter the basal tension of small and large MA but significantly increased their responses to PE, and reduced the effect of BKCa channels in opposing the contractile responses to PE without changes in the protein expression level of BKCa subunits. ET also elicited a size-dependent functional adaptations that involved reduced endothelium-independent and endothelium-dependent relaxations. In large MA the sensitivity to SNP was decreased more than in small MA suggesting impaired nitric oxide (NO)-dependent mechanisms within the vascular smooth muscle cells of ET group. Whereas the shift in pEC50 of ACh-induced relaxation of small MA would suggest more effect on the production of NO within the endothelium, which is not changed in large MA of ET group. However, the eNOS protein expression level was not significantly changed between the ET and SED groups. In conclusion, our results indicate an increase in contraction and reduced relaxation of MA after 10 weeks of ET, an adaptation that may help shunt blood flow to metabolically active tissues during acute exercise.