Sex-Specific Impacts of Exercise on Cardiovascular Remodeling

The Acquisition of Cardiovascular Adaptation to Aerobic Exercise: When Does It Begin and How Does It Evolve Depending on Intrinsic and Extrinsic Factors?

The acquisition and evolution of cardiovascular (CV) adaptation to physical activity or exercise training are critical in enhancing cardiorespiratory fitness and reducing CV disease (CVD) risk. CV adaptations to exercise occur through structural, functional, and molecular changes that enhance cardiac efficiency. These adaptations, such as increased stroke volume, improved blood pressure regulation, and enhanced endothelial function, collectively reduce CVD morbidity and mortality. In this review we explore how CV adaptations vary across different demographic characteristics, and highlight the importance of exercise timing, intensity, and recovery periods. We delve into the immediate physiological responses to physical activity, such as increased heart rate and cardiac output, and the longer-term adaptations, including cardiac hypertrophy and improved vascular function. The influence of age, sex, and preexisting health conditions on CV responses to exercise is also discussed, emphasizing the need for tailored exercise interventions. Finally, the review highlights the significance of recovery periods in optimizing CV adaptations and how insufficient recovery might lead to adverse outcomes. Overall, understanding the timing and evolution of CV adaptations can inform exercise prescriptions to improve CV health across populations for the primary and secondary prevention of CVD.

Sex differences in cardiac energetics in the rat ventricular muscle

Cardiac sex-difference functional studies have centred on measurements of twitch force and Ca2+ dynamics. The energy expenditures from these two cellular processes: activation (Ca2+ handling) and contraction (cross-bridge cycling), have not been assessed, and compared, between sexes. Whole-heart studies measuring oxygen consumption do not directly measure the energy expenditure of these activation-contraction processes. In this study, we directly quantified these energy expenditures in terms of heat production. Left-ventricular trabeculae were dissected from rats aged 9-13 weeks. Mechano-energetics of trabeculae were characterized using our work-loop calorimeter under various conditions including varying muscle lengths, stimulus frequencies, and afterloads. Each trabecula was subjected to protocols that allowed it to contract either isometrically or shorten to perform work-loops. Force production, length change, and heat output were simultaneously measured. We extracted various metrics: twitch kinetics, shortening kinetics, mechanical work, and heat associated with cross-bridge cycling and Ca2+ cycling, and quantified mechanical efficiency. Results show no sex differences in any of the metrics. Peak mechanical efficiency was not affected by sex (10.25 ± 0.57% in female trabeculae; 10.93 ± 0.87% in male trabeculae). We conclude that cardiac mechanics and energetics are not affected by sex at the muscle level, within the rat age range studied.

Combined cardiovascular effects of ovariectomy and high-intensity interval training in female spontaneously hypertensive rats

Hypertensive postmenopausal women are more likely to develop adverse cardiac remodeling and respond less effectively to drug treatment than men. High-intensity interval exercise (HIIE) is a nonpharmacological strategy for the treatment of hypertension; however, the effectiveness in women remains uncertain. This study was designed to evaluate 1) the effects of HIIE training upon morphological and functional markers of cardiovascular health in female SHR and 2) to determine whether the hormonal shift induced by ovariectomy could influence cardiovascular responses to HIIE. Thirty-six SHR were randomly assigned to four groups: ovariectomized sedentary, ovariectomized trained, sham-operated sedentary, and sham-operated trained. The trained rats performed HIIE 5 days/wk for 8 wk. Blood pressure and echocardiographic measurements were performed before and after training in animals. Cardiac response to β-adrenergic stimulation and the expression of calcium regulatory proteins and estrogen receptors in heart samples were assessed. Endothelium-dependent vasorelaxation in response to acetylcholine was evaluated in aortic rings as well as the expression of nitric oxide synthase isoforms (eNOS and P-eNOS) by Western blotting. In both groups of trained SHR, HIIE induced eccentric cardiac remodeling with greater inotropic and chronotropic effects, as well as an increase in SERCA and β1AR expression. However, although the trained rats showed improved endothelial function and expression of eNOS and P-eNOS in the aorta, there was no demonstrated effect on blood pressure. In addition, the responses to HIIE training were not affected by ovariectomy. This work highlights the importance of assessing the cardiovascular efficacy and safety of different exercise modalities in women.NEW & NOTEWORTHY This study reports the effects of high-intensity interval exercise (HIIE) training on cardiac and endothelial function in female hypertensive rats. Despite a lack of effect on blood pressure (BP), HIIE training induces eccentric cardiac remodeling with greater functionals effects. Furthermore, training has beneficial effects on endothelial function. However, ovarian hormones do not seem to modulate cardiac and aortic adaptations to this training modality. All this underlines the need to consider training modalities on the cardiovascular system in women.

Associations of Lifelong Exercise Characteristics With Valvular Function and Aortic Diameters in Patients With a Bicuspid Aortic Valve

BACKGROUND

The potential impact of exercise on valvular function and aortic diameters in patients with a bicuspid aortic valve remains unclear. Therefore, we assessed the association between lifelong exercise characteristics, valvular dysfunction, and aortic dilatation in patients with a bicuspid aortic valve.

METHODS AND RESULTS

In this cross-sectional study, exercise volume (metabolic equivalent of task minutes per week), exercise intensity, and sport type were determined from the age of 12 years to participation using a validated questionnaire. Echocardiography was used to assess aortic stenosis or aortic regurgitation and to measure diameters at the sinuses of Valsalva and ascending aorta. Aortic dilatation was defined as a Z-score ≥2. Four hundred and seven patients (42±17 years, 60% men) were included, of which 133 were sedentary (<500 metabolic equivalent of task minutes per week), 94 active (500-1000 metabolic equivalent of task minutes per week), and 180 highly active (≥1000 metabolic equivalent of task minutes per week). Moderate-to-severe aortic stenosis or aortic regurgitation was present in 23.7% and 20.0%, respectively. Sinuses of Valsalva and ascending aorta diameters were 34.8±6.6 and 36.5±8.1 mm, whereas aortic dilatation was found in 21.6% and 53.4%, respectively. Exercise volume was not associated with valve dysfunction or aortic dilatation. Vigorous intensity and mixed sports were associated with a lower prevalence of aortic stenosis (adjusted odds ratios, 0.43 [0.20-0.94] and adjusted odds ratios, 0.47 [0.23-0.95]). Exercise intensity and sport type were not associated with aortic regurgitation and aortic dilatation.

CONCLUSIONS

We found no deleterious associations between lifelong exercise characteristics, valvular dysfunction, and aortic dilatation in patients with a bicuspid aortic valve. Vigorous intensity and exercise in mixed sports were associated with a lower prevalence of moderate-to-severe aortic stenosis. These observations suggest that lifelong exercise does not appear to induce adverse cardiovascular effects in patients with a bicuspid aortic valve.

Moderate-Intensity and High-Intensity Interval Exercise Training Offer Equal Cardioprotection, with Different Mechanisms, during the Development of Type 2 Diabetes in Rats

Endurance exercise training is a promising cardioprotective strategy in type 2 diabetes mellitus (T2DM), but the impact of its intensity is not clear. We aimed to investigate whether and how isocaloric moderate-intensity exercise training (MIT) and high-intensity interval exercise training (HIIT) could prevent the adverse cardiac remodeling and dysfunction that develop T2DM in rats. Male rats received a Western diet (WD) to induce T2DM and underwent a sedentary lifestyle (n = 7), MIT (n = 7) or HIIT (n = 8). Insulin resistance was defined as the HOMA-IR value. Cardiac function was assessed with left ventricular (LV) echocardiography and invasive hemodynamics. A qPCR and histology of LV tissue unraveled underlying mechanisms. We found that MIT and HIIT halted T2DM development compared to in sedentary WD rats (p < 0.05). Both interventions prevented increases in LV end-systolic pressure, wall thickness and interstitial collagen content (p < 0.05). In LV tissue, HIIT tended to upregulate the gene expression of an ROS-generating enzyme (NOX4), while both modalities increased proinflammatory macrophage markers and cytokines (CD86, TNF-α, IL-1β; p < 0.05). HIIT promoted antioxidant and dicarbonyl defense systems (SOD2, glyoxalase 1; p < 0.05) whereas MIT elevated anti-inflammatory macrophage marker expression (CD206, CD163; p < 0.01). We conclude that both MIT and HIIT limit WD-induced T2DM with diastolic dysfunction and pathological LV hypertrophy, possibly using different adaptive mechanisms.

Guanxin V Relieves Ventricular Remodeling by Inhibiting Inflammation: Implication from Virtual Screening, Systematic Pharmacology, Molecular Docking, and Experimental Validation

OBJECTIVE

To reveal the anti-inflammatory mechanism of Guanxin V, which is prescribed for ventricular remodeling in clinical practice.

METHODS

Guanxin V-, ventricular remodeling-, and inflammation-related targets were obtained through an integrated strategy of virtual screening and systematic pharmacology, and then the shared targets were visualised with a Venn diagram. Guanxin V network and the protein-protein interaction network were drawn, and enrichment analysis was conducted. Finally, the main results obtained from the integrated strategy were validated by molecular docking and in vivo experiments.

RESULTS

A total of 251, 11,425, and 15,246 Guanxin V-, ventricular remodeling-, and inflammation-related targets were acquired, respectively. Then, 211 shared targets were considered to contribute to the mechanism of ventricular remodeling treated by Guanxin V. Guanxin network and the protein-protein interaction network were drawn, and enrichment analysis showed some cardiovascular-related biological processes and signaling pathways. Molecular docking revealed that the Guanxin V-derived compounds could align with key targets. Final in vivo experiments proved that Guanxin V reverses ventricular remodeling by inhibiting inflammation.

CONCLUSION

Guanxin V relieves ventricular remodeling by regulating inflammation, which provides new ideas for the anti-ventricular remodeling mechanism of Guanxin V.

Maternal high-intensity interval training as a suitable approach for offspring's heart protection in rat: evidence from oxidative stress and mitochondrial genes

Considerable scientific evidence suggests that the intrauterine environment plays a crucial role in determining the long-term health of offspring. The present study aims to investigate the effects of high-intensity interval training in maternal rats before and during pregnancy on the antioxidant status, mitochondrial gene expression, and anxiety-like behavior of their offspring. A total of thirty-two female rats were assigned to four maternal groups based on the timing of exercise: before pregnancy, before and during pregnancy, during pregnancy, and sedentary. The female and male offspring were allocated to groups that matched their mothers' exercise regimen. Anxiety-like behavior in the offspring was evaluated using the open-field and elevated plus-maze tests. Our findings indicate that maternal HIIT does not have any detrimental effect on the anxiety-related behavior of offspring. Also, maternal exercise before and during pregnancy could improve the general activity of the offspring. Furthermore, our results demonstrate that female offspring exhibit more locomotion activity than males. Besides, maternal HIIT leads to a reduction in the levels of TOS and MDA, while TAC levels increase, and significantly upregulate the gene expression of PGC1-α, NFR1, and NRF2 in both sexes in the heart. Therefore, our study suggests that maternal HIIT is a beneficial maternal behavior and serves as a cardioprotective agent to enhance the health of the next generations.

Is There Evidence for the Development of Sex-Specific Guidelines for Ultramarathon Coaches and Athletes? A Systematic Review

BACKGROUND

There is evidence of sex differences in the physiology of endurance exercise, yet most of the advice and guidelines on training, racing, nutrition, and recovery for ultramarathons are based on research that has largely excluded female athletes. The objective was therefore to review the current knowledge of sex differences in ultramarathon runners and determine if sufficient evidence exists for providing separate guidelines for males and females.

METHODS

This systematic review was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Three databases were searched for studies investigating differences in elite and recreational male and female ultramarathon runners. Studies were included if they compared males and females and looked at outcomes relating to the performance or health of ultramarathon runners. The quality of the included studies was determined using the Grading of Recommendations Assessment Development and Evaluation (GRADE) approach.

RESULTS

The search strategy identified 45 studies that met the inclusion criteria. Most studies were observational in design, with only three papers based on randomised controlled trials. The overall quality of the evidence was low. Sex differences in the predictors of ultramarathon performance; physiological responses to training, racing, and recovery; chronic and acute health issues; and pacing strategies were found. There were areas with contradictory findings, and very few studies examined specific interventions.

CONCLUSION

The results from this review suggest that the development of sex-specific guidelines for ultramarathon coaches and athletes could have a significant effect on the performance and health of female runners. At present, there is insufficient high-quality evidence on which to formulate these guidelines, and further research is required.

Selected Plant-Derived Polyphenols as Potential Therapeutic Agents for Peripheral Artery Disease: Molecular Mechanisms, Efficacy and Safety

Vascular diseases, such as peripheral artery disease (PAD), are associated with diabetes mellitus and a higher risk of cardiovascular disease and even death. Surgical revascularization and pharmacological treatments (mainly antiplatelet, lipid-lowering drugs, and antidiabetic agents) have some effectiveness, but the response and efficacy of therapy are overly dependent on the patient’s conditions. Thus, the demand for new cures exists. In this regard, new studies on natural polyphenols that act on key points involved in the pathogenesis of vascular diseases and, thus, on PAD are of great urgency. The purpose of this review is to take into account the mechanisms that lead to endothelium dysfunction, such as the glycoxidation process and the production of advanced glycation end-products (AGEs) that result in protein misfolding, and to suggest plant-derived polyphenols that could be useful in PAD. Thus, five polyphenols are considered, baicalein, curcumin, mangiferin, quercetin and resveratrol, reviewing the literature in PubMed. The key molecular mechanisms and preclinical and clinical studies of each selected compound are examined. Furthermore, the safety profiles of the polyphenols are outlined, together with the unwanted effects reported in humans, also by searching the WHO database (VigiBase).

Exercise training maintains cardiovascular health: signaling pathways involved and potential therapeutics

Exercise training has been widely recognized as a healthy lifestyle as well as an effective non-drug therapeutic strategy for cardiovascular diseases (CVD). Functional and mechanistic studies that employ animal exercise models as well as observational and interventional cohort studies with human participants, have contributed considerably in delineating the essential signaling pathways by which exercise promotes cardiovascular fitness and health. First, this review summarizes the beneficial impact of exercise on multiple aspects of cardiovascular health. We then discuss in detail the signaling pathways mediating exercise's benefits for cardiovascular health. The exercise-regulated signaling cascades have been shown to confer myocardial protection and drive systemic adaptations. The signaling molecules that are necessary for exercise-induced physiological cardiac hypertrophy have the potential to attenuate myocardial injury and reverse cardiac remodeling. Exercise-regulated noncoding RNAs and their associated signaling pathways are also discussed in detail for their roles and mechanisms in exercise-induced cardioprotective effects. Moreover, we address the exercise-mediated signaling pathways and molecules that can serve as potential therapeutic targets ranging from pharmacological approaches to gene therapies in CVD. We also discuss multiple factors that influence exercise's effect and highlight the importance and need for further investigations regarding the exercise-regulated molecules as therapeutic targets and biomarkers for CVD as well as the cross talk between the heart and other tissues or organs during exercise. We conclude that a deep understanding of the signaling pathways involved in exercise's benefits for cardiovascular health will undoubtedly contribute to the identification and development of novel therapeutic targets and strategies for CVD.

Cardiodiagnostic sex-specific differences of the female athlete in sports cardiology

The cardiovascular care of highly active individuals and competitive athletes has developed into an important focus within the field of sports medicine. An evolving understanding of exercise-induced cardiovascular remodeling in athletes has led to a more robust characterization of physiologic adaptation versus pathological dysfunction, but this distinction is often challenging due to diagnostic commonalities. Current data reflects sporting-focused analyses of mainly male athletes, which may not be easily applicable to the female athletic heart. Increasingly female-specific cardiac dimensional and physiologic data are starting to emerge from comparative studies that may be utilized to address this growing need, and further guide individualized care. Here, we review current literature evaluating female-specific cardiovascular adaptations of the athletic heart, and formulate a discussion on cardiac remodeling, cardiodiagnostic findings, etiologic mechanisms, limitations of currently available data, and direction for future research in the cardiovascular care of female athletes.

Effects of Different Intensities and Durations of Aerobic Exercise on Vascular Endothelial Function in Middle-Aged and Elderly People: A Meta-analysis

Background

Previous studies have found that aerobic exercise was more effective in improving vascular endothelial function than resistance training, high-intensity interval training (HIIT), and other types of exercise, while the effects between different intensities and durations of aerobic exercise were unclear. Therefore, we performed this meta-analysis to investigate the effects of different intensities and durations of aerobic exercise on the vascular endothelial function of middle-aged and elderly people.

Methods:

Databases were searched up to April 2021 for studies evaluating the influences of different intensities and durations of aerobic exercise on endothelial function assessed by flow-mediated dilation (FMD) among healthy middle-aged and elderly people. Data were pooled using random-effects models to obtain the weighted mean difference (WMD) and 95% confidence intervals (CIs).

Results

A total of 9 studies involving 221 participants fulfilled the inclusion criteria. Aerobic exercise improved the overall FMD of healthy middle-aged and elderly people [WMD, 1.33 (95% CI, 0.37–2.28), P < 0.05]. Specifically, vigorous-intensity exercise increased FMD significantly in healthy middle-aged and elderly people [WMD, 1.10 (95% CI, 0.27–1.93), P < 0.05], while moderate-intensity exercise had no significant association with FMD [WMD, 1.49 (95% CI, −0.62 to 3.60), P = 0.17]. In addition, long-term (8 weeks or above) aerobic exercise increased the FMD in healthy middle-aged and elderly people [WMD, 1.63 (95% CI, 0.61–2.66), P < 0.05], while one-time acute aerobic exercise had no significant association with FMD of healthy middle-aged and elderly people [WMD, 0.89 (95% CI, −1.47 to 3.24), P = 0.46]. Specifically, 8 weeks or above of vigorous-intensity exercise increased FMD significantly in healthy middle-aged and elderly people [WMD, 1.48 (95% CI, 1.06–1.90), P < 0.01], while 8 weeks or above of moderate aerobic exercise had no significant association with FMD [WMD, 1.49 (95% CI, −0.62 to 3.60), P = 0.17].

Conclusion

Aerobic exercise, especially 8 weeks or above of vigorous-intensity aerobic exercise, improved the endothelial function in healthy middle-aged and elderly people.

The Role of Estrogens and Vitamin D in Cardiomyocyte Protection: A Female Perspective

Women experience a dramatical raise in cardiovascular events after menopause. The decline in estrogens is pointed to as the major responsible trigger for the increased risk of cardiovascular disease (CVD). Indeed, the menopausal transition associates with heart macro-remodeling, which results from a fine-tuned cell micro-remodeling. The remodeling of cardiomyocytes is a biomolecular response to several physiologic and pathologic stimuli, allowing healthy adaptation in normal conditions or maladaptation in an unfavorable environment, ending in organ architecture disarray. Estrogens largely impinge on cardiomyocyte remodeling, but they cannot fully explain the sex-dimorphism of CVD risk. Albeit cell remodeling and adaptation are under multifactorial regulation, vitamin D emerges to exert significant protective effects, controlling some intracellular paths, often shared with estrogen signaling. In post-menopause, the unfavorable association of hypoestrogenism-D hypovitaminosis may converge towards maladaptive remodeling and contribute to increased CVD risk. The aim of this review is to overview the role of estrogens and vitamin D in female cardiac health, speculating on their potential synergistic effect in cardiomyocyte remodeling, an issue that is not yet fully explored. Further learning the crosstalk between these two steroids in the biomolecular orchestration of cardiac cell fate during adaptation may help the translational approach to future cardioprotective strategies for women health.