Aerobic exercise training reduces cardiac function and coronary flow-induced vasodilation in mice lacking adiponectin

Cardioprotection of voluntary exercise against breast cancer-induced cardiac injury via STAT3

Exercise is an effective way to alleviate breast cancer-induced cardiac injury to a certain extent. However, whether voluntary exercise (VE) activates cardiac signal transducer and activator of transcription 3 (STAT3) and the underlying mechanisms remain unclear. This study investigated the role of STAT3-microRNA(miRNA)-targeted protein axis in VE against breast cancer-induced cardiac injury.VE for 4 weeks not only improved cardiac function of transgenic breast cancer female mice [mouse mammary tumor virus-polyomavirus middle T antigen (MMTV-PyMT +)] compared with littermate mice with no cancer (MMTV-PyMT -), but also increased myocardial STAT3 tyrosine 705 phosphorylation. Significantly more obvious cardiac fibrosis, smaller cardiomyocyte size, lower cell viability, and higher serum tumor necrosis factor (TNF)-α were shown in MMTV-PyMT + mice compared with MMTV-PyMT - mice, which were ameliorated by VE. However, VE did not influence the tumor growth. MiRNA sequencing identified that miR-181a-5p was upregulated and miR-130b-3p was downregulated in VE induced-cardioprotection. Myocardial injection of Adeno-associated virus serotype 9 driving STAT3 tyrosine 705 mutations abolished cardioprotective effects above. Myocardial STAT3 was identified as the transcription factor binding the promoters of pri-miR-181a (the precursor of miR-181a-5p) and HOX transcript antisense RNA (HOTAIR, sponged miR-130b-3p) in isolated cardiomyocytes. Furthermore, miR-181a-5p targeting PTEN and miR-130b-3p targeting Zinc finger and BTB domain containing protein 20 (Zbtb20) were proved in AC-16 cells. These findings indicated that VE protects against breast cancer-induced cardiac injury via activating STAT3 to promote miR-181a-5p targeting PTEN and to promote HOTAIR to sponge miR-130b-3p targeting Zbtb20, helping to develop new targets in exercise therapy for breast cancer-induced cardiac injury.

The effect of resistance training and nandrolone decanoate administration on cardiac tissue in mice

PURPOSE

This study examined the effect of resistance training (RT) by itself and in combination with supraphysiological administration of nandrolone decanoate (ND) on the inflammatory, apoptotic, and oxidative stress response in cardiac tissue. The effect of the training and androgen intervention on adiponectin expression, a potential cardio protectant was also examined.

METHODS

Forty male C57Bl/6J mice, 3 months of age were randomized into four groups (n = 10 per group). Two groups of animals performed a 3-day per week RT program for 7-weeks, while the other two groups remained sedentary (SED). The RT and SED animals were further randomized into an androgen group (RTA and SEDA, respectively) or a sham group (RTS and SEDS, respectively). Animals in the RTA and SEDA groups received 38-mg·kg-1 injected once per week. Mice from RTS and SEDS received sham injections.

RESULTS

Main effects for group indicated that RT resulted in significant elevations in NFκβ (p < 0.001), glutamine peroxidase (GPX) (p = 0.007) and adiponectin (p < 0.001). Main effects for treatment indicated that ND administration resulted in greater elevations in NFκβ (p = 0.01) and TNF-α (p = 0.017). In addition, TNF-α expression was greater in RTA compared to RETS (p = 0.006) and the adiponectin response in RTA was greater (p's < 0.05) than all other groups. A significant correlation was noted between average training volume during the RT program and GPX expression (r = 0.716, p < 0.001).

CONCLUSION

Results indicate that RT and ND administration can increase markers of apoptosis and inflammation. Elevations in adiponectin expression suggest that it may act as a compensatory mechanism supporting cardiovascular health.

Realistic Aspects of Cardiac Ultrasound in Rats: Practical Tips for Improved Examination

Echocardiography is a reliable and non-invasive method for assessing cardiac structure and function in both clinical and experimental settings, offering valuable insights into disease progression and treatment efficacy. The successful application of echocardiography in murine models of disease has enabled the evaluation of disease severity, drug testing, and continuous monitoring of cardiac function in these animals. However, there is insufficient standardization of echocardiographic measurements for smaller animals. This article aims to address this gap by providing a guide and practical tips for the appropriate acquisition and analysis of echocardiographic parameters in adult rats, which may also be applicable in other small rodents used for scientific purposes, like mice. With advancements in technology, such as ultrahigh-frequency ultrasonic transducers, echocardiography has become a highly sophisticated imaging modality, offering high temporal and spatial resolution imaging, thereby allowing for real-time monitoring of cardiac function throughout the lifespan of small animals. Moreover, it allows the assessment of cardiac complications associated with aging, cancer, diabetes, and obesity, as well as the monitoring of cardiotoxicity induced by therapeutic interventions in preclinical models, providing important information for translational research. Finally, this paper discusses the future directions of cardiac preclinical ultrasound, highlighting the need for continued standardization to advance research and improve clinical outcomes to facilitate early disease detection and the translation of findings into clinical practice.

Exerkines and cardiometabolic benefits of exercise: from bench to clinic

Regular exercise has both immediate and long-lasting benefits on cardiometabolic health, and has been recommended as a cornerstone of treatment in the management of diabetes and cardiovascular conditions. Exerkines, which are defined as humoral factors responsive to acute or chronic exercise, have emerged as important players conferring some of the multiple cardiometabolic benefits of exercise. Over the past decades, hundreds of exerkines released from skeletal muscle, heart, liver, adipose tissue, brain, and gut have been identified, and several exerkines (such as FGF21, IL-6, and adiponectin) have been exploited therapeutically as exercise mimetics for the treatment of various metabolic and cardiovascular diseases. Recent advances in metagenomics have led to the identification of gut microbiota, a so-called "hidden" metabolic organ, as an additional class of exerkines determining the efficacy of exercise in diabetes prevention, cardiac protection, and exercise performance. Furthermore, multiomics-based studies have shown the feasibility of using baseline exerkine signatures to predict individual responses to exercise with respect to metabolic and cardiorespiratory health. This review aims to explore the molecular pathways whereby exerkine networks mediate the cardiometabolic adaptations to exercise by fine-tuning inter-organ crosstalk, and discuss the roadmaps for translating exerkine-based discovery into the therapeutic application and personalized medicine in the management of the cardiometabolic disease.

Influence of Supervised Maternal Aerobic Exercise during Pregnancy on 1-Month-Old Neonatal Cardiac Function and Outflow: A Pilot Study

PURPOSE

The objective of this study is to assess the effects of supervised, recommended levels of prenatal aerobic exercise on 1-month-old infant cardiac function.

METHODS

Eligible pregnant women were randomly assigned to either an aerobic exercise group that participated in 150 min of supervised, moderate-intensity (40% to 59% V̇O 2peak , 12 to 14 on Borg rating of perceived exertion) aerobic exercise per week for 24 wk or more or a nonexercising group that consisted of 150 min·wk -1 of relaxation techniques. One-month-old infant echocardiogram was performed to assess infant cardiac function , including heart rate (HR), left-ventricular stroke volume, cardiac output, cardiac index, ejection fraction, fractional shortening, and velocity time integral at the aortic valve. Pearson correlation analyses and linear regression models were performed.

RESULTS

Prenatal aerobic exercise was negatively correlated with infant resting HR ( r = -0.311, P = 0.02). Similarly, when controlling for infant sex and activity state, exercise level/volume ( β = -0.316; 95% CI, -0.029 to -0.002; P = 0.02) predicted resting infant HR ( R2 = 0.18, P = 0.02). In infants of overweight/obese women, infants of aerobic exercisers had increased fractional shortening ( P = 0.03). In addition, infant ventricular ejection fraction was correlated with maternal exercise attendance ( r = 0.418, P = 0.03) as well as a trend for exercise level ( r = 0.351, P = 0.08). Similarly, the only significant regression model for infants of overweight/obese women controls infant activity state ( β = -0.444; 95% CI, -0.05 to -0.01; P = 0.006) and maternal exercise level ( β = 0.492; 95% CI, 5.46-28.74; P = 0.01) predicting infant resting HR ( F = 5.79, R2 = 0.40, P = 0.003).

CONCLUSIONS

The findings of this study demonstrate that women participating in exercise in the second and third trimesters of their pregnancy may have infants with increased cardiac function at 1 month of age. Importantly, the cardiac function effects were further augmented for infants born to overweight/obese women.

AKT Mediates Adiponectin-Dependent Regulation of VSMC Phenotype

Adiponectin (adipoq), the most abundant hormone in circulation, has many beneficial effects on the cardiovascular system, in part by preserving the contractile phenotype of vascular smooth muscle cells (VSMCs). However, the lack of adiponectin or its receptor and treatment with recombinant adiponectin have shown contradictory effects on plaque in mice. RNA sequence of Adipoq+/+ and adipoq-/- VSMCs from male aortas identified a critical role for adiponectin in AKT signaling, the extracellular matrix (ECM), and TGF-β signaling. Upregulation of AKT activity mediated proliferation and migration of adipoq-/- cells. Activation of AMPK with metformin or AdipoRon reduced AKT-dependent proliferation and migration of adipoq-/- cells but did not improve the expression of contractile genes. Adiponectin deficiency impaired oxidative phosphorylation (OXPHOS), increased expression of glycolytic enzymes, and elevated mitochondrial reactive oxygen species (ROS) (superoxide, and hydrogen peroxide). Anti-atherogenic mechanisms targeted the ECM in adipoq-/- cells, downregulating MMP2 and 9 and upregulating decorin (DCN) and elastin (ELN). In vivo, the main sex differences in protein expression in aortas involved a more robust upregulation of MMP3 in females than males. Females also showed a reduction in DCN, which was not affected in males. Our study uncovered the AKT/MAPK/TGF-β network as a central regulator of VSMC phenotype.

Effect of functional resistance training on the structure and function of the heart and liver in patients with non-alcoholic fatty liver

The current study is of the quasi-experimental type, with a pre-and post-test design, and subjects were randomly assigned to one of two groups: control (n = 8) and experimental (test) (n = 8). Based on the patient's self-report and using daily diet control tables, the patient's diet planning percentage of energy supply was managed and controlled for 3 days. The protocol for functional resistance training for these circular exercises, including the squat, lunge, bear crawl, rock press, jumping jack, and back fly lunge, was performed three times per week without specialized apparatus. Ejection fraction (EF) and fractional shortening (FS) were measured before and after functional resistance training, using echocardiography. Liver Stiffness and steatosis were measured using FibroScan, and the liver function was determined using biochemical assays. The average age of patients in the control group and the test group were 46.02 ± 5.4 and 48.6 ± 2.51, respectively. Pre-test and post-test of the body mass index were 32.06 ± 5.06 and 30.02 ± 3.97, and for the body fat percentage were 33.65 ± 6.09 and 25.41 ± 4.99. In non-alcoholic fatty liver patients, due to functional resistance training, EF (p-value = 0.003) and FS (p-value = 0.03) significantly increased, and C-reactive protein (Hs-CRP) (p-value = 0.001), steatosis (p-value = 0.04), and stiffness (p-value = 0.01) decreased. According to the results and without considering clinical trials, functional resistance training affects the structure and function of the heart and Liver in NAFLD patients.

Mechanisms and clinical implications of endothelium-dependent vasomotor dysfunction in coronary microvasculature

Coronary microvascular disease (CMD), which affects the arterioles and capillary endothelium that regulate myocardial perfusion, is an increasingly recognized source of morbidity and mortality, particularly in the setting of metabolic syndrome. The coronary endothelium plays a pivotal role in maintaining homeostasis, though factors such as diabetes, hypertension, hyperlipidemia, and obesity can contribute to endothelial injury and consequently arteriolar vasomotor dysfunction. These disturbances in the coronary microvasculature clinically manifest as diminished coronary flow reserve, which is a known independent risk factor for cardiac death, even in the absence of macrovascular atherosclerotic disease. Therefore, a growing body of literature has examined the molecular mechanisms by which coronary microvascular injury occurs at the level of the endothelium and the consequences on arteriolar vasomotor responses. This review will begin with an overview of normal coronary microvascular physiology, modalities of measuring coronary microvascular function, and clinical implications of CMD. These introductory topics will be followed by a discussion of recent advances in the understanding of the mechanisms by which inflammation, oxidative stress, insulin resistance, hyperlipidemia, hypertension, shear stress, endothelial cell senescence, and tissue ischemia dysregulate coronary endothelial homeostasis and arteriolar vasomotor function.

Vascular endothelial adiponectin signaling across the life span

Cardiovascular disease risk increases with age regardless of sex. Some of this risk is attributable to alterations in natural hormones throughout the life span. The quintessential example of this being the dramatic increase in cardiovascular disease following the transition to menopause. Plasma levels of adiponectin, a "cardioprotective" adipokine released primarily by adipose tissue and regulated by hormones, also fluctuate throughout one's life. Plasma adiponectin levels increase with age in both men and women, with higher levels in both pre- and postmenopausal women compared with men. Younger cohorts seem to confer cardioprotective benefits from increased adiponectin levels yet elevated levels in the elderly and those with existing heart disease are associated with poor cardiovascular outcomes. Here, we review the most recent data regarding adiponectin signaling in the vasculature, highlight the differences observed between the sexes, and shed light on the apparent paradox regarding increased cardiovascular disease risk despite rising plasma adiponectin levels over time.