Characterization, number, and spatial organization of nerve fibers in the human cervical vagus nerve and its superior cardiac branch

BACKGROUND

Electrical stimulation of the vagus nerve (VN) is a therapy for epilepsy, obesity, depression, and heart diseases. However, whole nerve stimulation leads to side effects. We examined the neuroanatomy of the mid-cervical segment of the human VN and its superior cardiac branch to gain insight into the side effects of VN stimulation and aid in developing targeted stimulation strategies.

METHODS

Nerve specimens were harvested from eight human body donors, then subjected to immunofluorescence and semiautomated quantification to determine the signature, quantity, and spatial distribution of different axonal categories.

RESULTS

The right and left cervical VN (cVN) contained a total of 25,489 ± 2,781 and 23,286 ± 3,164 fibers, respectively. Two-thirds of the fibers were unmyelinated and one-third were myelinated. About three-quarters of the fibers in the right and left cVN were sensory (73.9 ± 7.5% versus 72.4 ± 5.6%), while 13.2 ± 1.8% versus 13.3 ± 3.0% were special visceromotor and parasympathetic, and 13 ± 5.9% versus 14.3 ± 4.0% were sympathetic. Special visceromotor and parasympathetic fibers formed clusters. The superior cardiac branches comprised parasympathetic, vagal sensory, and sympathetic fibers with the left cardiac branch containing more sympathetic fibers than the right (62.7 ± 5.4% versus 19.8 ± 13.3%), and 50% of the left branch contained sensory and sympathetic fibers only.

CONCLUSION

The study indicates that selective stimulation of vagal sensory and motor fibers is possible. However, it also highlights the potential risk of activating sympathetic fibers in the superior cardiac branch, especially on the left side.

Selenosugars targeting the infective stage of Trypanosoma brucei with high selectivity

Earlier evidences showed that diglycosyl diselenides are active against the infective stage of African trypanosomes (top hits IC50 0.5 and 1.5 μM) but poorly selective (selectivity index <10). Here we extended the study to 33 new seleno-glycoconjugates with the aim to improve potency and selectivity. Three selenoglycosides and three glycosyl selenenylsulfides displayed IC50 against bloodstream Trypanosoma brucei in the sub-μM range (IC50 0.35-0.77 μM) and four of them showed an improved selectivity (selectivity index >38-folds vs. murine and human macrohages). For the glycosyl selenylsulfides, the anti-trypanosomal activity was not significantly influenced by the nature of the moiety attached to the sulfur atom. Except for a quinoline-, and to a minor extent a nitro-derivative, the most selective hits induced a rapid (within 60 min) and marked perturbation of the LMWT-redox homeostasis. The formation of selenenylsulfide glycoconjugates with free thiols has been identified as a potential mechanism involved in this process.

Reduced Monocyte and Neutrophil Infiltration and Activation by P-Selectin/CD62P Inhibition Enhances Thrombus Resolution in Mice

BACKGROUND

Venous thromboembolism is a major health problem. After thrombus formation, its resolution is essential to re-establish blood flow, which is crucially mediated by infiltrating neutrophils and monocytes in concert with activated platelets and endothelial cells. Thus, we aimed to modulate leukocyte function during thrombus resolution post-thrombus formation by blocking P-selectin/CD62P-mediated cell interactions.

METHODS

Thrombosis was induced by inferior vena cava stenosis through ligation in mice. After 1 day, a P-selectin-blocking antibody or isotype control was administered and thrombus composition and resolution were analyzed.

RESULTS

Localizing neutrophils and macrophages in thrombotic lesions of wild-type mice revealed that these cells enter the thrombus and vessel wall from the caudal end. Neutrophils were predominantly present 1 day and monocytes/macrophages 3 days after vessel ligation. Blocking P-selectin reduced circulating platelet-neutrophil and platelet-Ly6Chigh monocyte aggregates near the thrombus, and diminished neutrophils and Ly6Chigh macrophages in the cranial thrombus part compared with isotype-treated controls. Depletion of neutrophils 1 day after thrombus initiation did not phenocopy P-selectin inhibition but led to larger thrombi compared with untreated controls. In vitro, P-selectin enhanced human leukocyte function as P-selectin-coated beads increased reactive oxygen species production by neutrophils and tissue factor expression of classical monocytes. Accordingly, P-selectin inhibition reduced oxidative burst in the thrombus and tissue factor expression in the adjacent vessel wall. Moreover, blocking P-selectin reduced thrombus density determined by scanning electron microscopy and increased urokinase-type plasminogen activator levels in the thrombus, which accelerated caudal fibrin degradation from day 3 to day 14. This accelerated thrombus resolution as thrombus volume declined more rapidly after blocking P-selectin.

CONCLUSIONS

Inhibition of P-selectin-dependent activation of monocytes and neutrophils accelerates venous thrombosis resolution due to reduced infiltration and activation of innate immune cells at the site of thrombus formation, which prevents early thrombus stabilization and facilitates fibrinolysis.

Role of the kisspeptin-KISS1R axis in the pathogenesis of chronic kidney disease and uremic cardiomyopathy

The prevalence of chronic kidney disease (CKD) is increasing globally, especially in elderly patients. Uremic cardiomyopathy is a common cardiovascular complication of CKD, characterized by left ventricular hypertrophy (LVH), diastolic dysfunction, and fibrosis. Kisspeptins and their receptor, KISS1R, exert a pivotal influence on kidney pathophysiology and modulate age-related pathologies across various organ systems. KISS1R agonists, including kisspeptin-13 (KP-13), hold promise as novel therapeutic agents within age-related biological processes and kidney-related disorders. Our investigation aimed to elucidate the impact of KP-13 on the trajectory of CKD and uremic cardiomyopathy. Male Wistar rats (300-350 g) were randomized into four groups: (I) sham-operated, (II) 5/6 nephrectomy-induced CKD, (III) CKD subjected to a low dose of KP-13 (intraperitoneal 13 µg/day), and (IV) CKD treated with a higher KP-13 dose (intraperitoneal 26 µg/day). Treatments were administered daily from week 3 for 10 days. After 13 weeks, KP-13 increased systemic blood pressure, accentuating diastolic dysfunction's echocardiographic indicators and intensifying CKD-associated markers such as serum urea levels, glomerular hypertrophy, and tubular dilation. Notably, KP-13 did not exacerbate circulatory uremic toxin levels, renal inflammation, or fibrosis markers. In contrast, the higher KP-13 dose correlated with reduced posterior and anterior wall thickness, coupled with diminished cardiomyocyte cross-sectional areas and concurrent elevation of inflammatory (Il6, Tnf), fibrosis (Col1), and apoptosis markers (Bax/Bcl2) relative to the CKD group. In summary, KP-13's influence on CKD and uremic cardiomyopathy encompassed heightened blood pressure and potentially activated inflammatory and apoptotic pathways in the left ventricle.

Consensus statement-graft treatment in cardiovascular bypass graft surgery

Coronary artery bypass grafting (CABG) is and continues to be the preferred revascularization strategy in patients with multivessel disease. Graft selection has been shown to influence the outcomes following CABG. During the last almost 60 years saphenous vein grafts (SVG) together with the internal mammary artery have become the standard of care for patients undergoing CABG surgery. While there is little doubt about the benefits, the patency rates are constantly under debate. Despite its acknowledged limitations in terms of long-term patency due to intimal hyperplasia, the saphenous vein is still the most often used graft. Although reendothelialization occurs early postoperatively, the process of intimal hyperplasia remains irreversible. This is due in part to the persistence of high shear forces, the chronic localized inflammatory response, and the partial dysfunctionality of the regenerated endothelium. "No-Touch" harvesting techniques, specific storage solutions, pressure controlled graft flushing and external stenting are important and established methods aiming to overcome the process of intimal hyperplasia at different time levels. Still despite the known evidence these methods are not standard everywhere. The use of arterial grafts is another strategy to address the inferior SVG patency rates and to perform CABG with total arterial revascularization. Composite grafting, pharmacological agents as well as latest minimal invasive techniques aim in the same direction. To give guide and set standards all graft related topics for CABG are presented in this expert opinion document on graft treatment.

Empagliflozin treatment rescues abnormally reduced Na+ currents in ventricular cardiomyocytes from dystrophin-deficient mdx mice

Cardiac arrhythmias significantly contribute to mortality in Duchenne muscular dystrophy (DMD), a severe muscle illness caused by mutations in the gene encoding for the intracellular protein dystrophin. A major source for arrhythmia vulnerability in patients with DMD is impaired ventricular impulse conduction, which predisposes for ventricular asynchrony, decreased cardiac output, and the development of reentrant circuits. Using the dystrophin-deficient mdx mouse model for human DMD, we previously reported that the lack of dystrophin causes a significant loss of peak Na+ current (INa) in ventricular cardiomyocytes. This finding provided a mechanistic explanation for ventricular conduction defects and concomitant arrhythmias in the dystrophic heart. In the present study, we explored the hypothesis that empagliflozin (EMPA), an inhibitor of sodium/glucose cotransporter 2 in clinical use to treat type II diabetes and nondiabetic heart failure, rescues peak INa loss in dystrophin-deficient ventricular cardiomyocytes. We found that INa of cardiomyocytes derived from mdx mice, which had received clinically relevant doses of EMPA for 4 wk, was restored to wild-type level. Moreover, incubation of isolated mdx ventricular cardiomyocytes with 1 µM EMPA for 24 h significantly increased their peak INa. This effect was independent of Na+-H+ exchanger 1 inhibition by the drug. Our findings imply that EMPA treatment can rescue abnormally reduced peak INa of dystrophin-deficient ventricular cardiomyocytes. Long-term EMPA administration may diminish arrhythmia vulnerability in patients with DMD.NEW & NOTEWORTHY Dystrophin deficiency in cardiomyocytes leads to abnormally reduced Na+ currents. These can be rescued by long-term empagliflozin treatment.

Angiography-based coronary microvascular assessment with and without intracoronary pressure measurements: a systematic review

BACKGROUND

In recent years, several indices have been proposed for quantifying coronary microvascular resistance. We intended to conduct a comprehensive review that systematically evaluates indices of microvascular resistance derived from angiography.

OBJECTIVE

The objective of this study was to identify and analyze angiography-derived indices of microvascular resistance that have been validated against an invasive reference method. We aimed to compare their limits of agreement with their reference methods and explore their advantages and inherent limitations.

METHODS AND RESULTS

We searched PubMed from inception until 2022 for studies on different techniques for quantifying microvascular resistance. Seven studies met the inclusion criteria. Five studies included techniques that applied calculations based solely on invasive angiography, and were validated against invasively measured thermodilution-derived index of microvascular resistance. The remaining two studies combined angiography with invasively measured intracoronary pressure data, and were validated against invasive Doppler measurements. We converted the ± 1.96 standard deviation limits of agreement with the reference method from the seven studies into percentages relative to the cut-off value of the reference method. The lower limits of agreement for angiography-based methods ranged from - 122 to - 60%, while the upper limits ranged from 74 to 135%. The range of the limits of agreement was considerably lower for the two combined angiography- and pressure-based methods, standing at - 52 to 60% and - 25 to 27%.

CONCLUSION

Our findings suggest that combined angiography- and pressure-based methods provide a more reliable assessment of microvascular resistance compared to methods relying solely on angiography. Central illustration. Comparative assessment of image-based methods quantifying microvascular resistance with and without intracoronary pressure measurements. Angiography-based methods rely on angiography alone to calculate the microvascular resistance by utilizing angiographic frame counting to extrapolate coronary flow (Q) and subsequently deriving distal coronary pressure using fluid dynamic equations. Combined angiography- and pressure-based methods utilize invasive intracoronary pressure gradients measured during rest and maximal vasodilation to determine coronary flow in their calculation of microvascular resistance. The combined methods showed more acceptable levels of agreement with their reference methods compared to angiography-based methods alone.

An mTORC1-Dependent Mouse Model for Cardiac Sarcoidosis

Background Sarcoidosis is an inflammatory, granulomatous disease of unknown cause affecting multiple organs, including the heart. Untreated, unresolved granulomatous inflammation can lead to cardiac fibrosis, arrhythmias, and eventually heart failure. Here we characterize the cardiac phenotype of mice with chronic activation of mammalian target of rapamycin (mTOR) complex 1 signaling in myeloid cells known to cause spontaneous pulmonary sarcoid-like granulomas. Methods and Results The cardiac phenotype of mice with conditional deletion of the tuberous sclerosis 2 (TSC2) gene in CD11c+ cells (TSC2fl/flCD11c-Cre; termed TSC2KO) and controls (TSC2fl/fl) was determined by histological and immunological stains. Transthoracic echocardiography and invasive hemodynamic measurements were performed to assess myocardial function. TSC2KO animals were treated with either everolimus, an mTOR inhibitor, or Bay11-7082, a nuclear factor-kB inhibitor. Activation of mTOR signaling was evaluated on myocardial samples from sudden cardiac death victims with a postmortem diagnosis of cardiac sarcoidosis. Chronic activation of mTORC1 signaling in CD11c+ cells was sufficient to initiate progressive accumulation of granulomatous infiltrates in the heart, which was associated with increased fibrosis, impaired cardiac function, decreased plakoglobin expression, and abnormal connexin 43 distribution, a substrate for life-threatening arrhythmias. Mice treated with the mTOR inhibitor everolimus resolved granulomatous infiltrates, prevented fibrosis, and improved cardiac dysfunction. In line, activation of mTOR signaling in CD68+ macrophages was detected in the hearts of sudden cardiac death victims who suffered from cardiac sarcoidosis. Conclusions To our best knowledge this is the first animal model of cardiac sarcoidosis that recapitulates major pathological hallmarks of human disease. mTOR inhibition may be a therapeutic option for patients with cardiac sarcoidosis.

MicroRNA-30d-5p-A Potential New Therapeutic Target for Prevention of Ischemic Cardiomyopathy after Myocardial Infarction

(1) Background and Objective: MicroRNAs (miRs) are biomarkers for assessing the extent of cardiac remodeling after myocardial infarction (MI) and important predictors of clinical outcome in heart failure. Overexpression of miR-30d-5p appears to have a cardioprotective effect. The aim of the present study was to demonstrate whether miR-30d-5p could be used as a potential therapeutic target to improve post-MI adverse remodeling. (2) Methods and Results: MiR profiling was performed by next-generation sequencing to assess different expression patterns in ischemic vs. healthy myocardium in a rat model of MI. MiR-30d-5p was significantly downregulated (p < 0.001) in ischemic myocardium and was selected as a promising target. A mimic of miR-30d-5p was administered in the treatment group, whereas the control group received non-functional, scrambled siRNA. To measure the effect of miR-30d-5p on infarct area size of the left ventricle, the rats were randomized and treated with miR-30d-5p or scrambled siRNA. Histological planimetry was performed 72 h and 6 weeks after induction of MI. Infarct area was significantly reduced at 72 h and at 6 weeks by using miR-30d-5p (72 h: 22.89 ± 7.66% vs. 35.96 ± 9.27%, p = 0.0136; 6 weeks: 6.93 ± 4.58% vs. 12.48 ± 7.09%, p = 0.0172). To gain insight into infarct healing, scratch assays were used to obtain information on cell migration in human umbilical vein endothelial cells (HUVECs). Gap closure was significantly faster in the mimic-treated cells 20 h post-scratching (12.4% more than the scrambled control after 20 h; p = 0.013). To analyze the anti-apoptotic quality of miR-30d-5p, the ratio between phosphorylated p53 and total p53 was evaluated in human cardiomyocytes using ELISA. Under the influence of the miR-30d-5p mimic, cardiomyocytes demonstrated a decreased pp53/total p53 ratio (0.66 ± 0.08 vs. 0.81 ± 0.17), showing a distinct tendency (p = 0.055) to decrease the apoptosis rate compared to the control group. (3) Conclusion: Using a mimic of miR-30d-5p underlines the cardioprotective effect of miR-30d-5p in MI and could reduce the risk for development of ischemic cardiomyopathy.

The type of suture material affects transverse aortic constriction-induced heart failure development in mice: a repeated measures correlation analysis

Introduction

Transverse-aortic constriction (TAC) operation is a widely used animal model to induce hypertrophy and heart failure through left-ventricular pressure overload. In mice, the cardiac response to TAC exhibits considerable variability influenced by factors such as strain, sub-strain, age, sex and vendor.

Methods

To investigate the impact of suture material (silk versus prolene) and size (6-0 versus 7-0) on the TAC-induced phenotype, we performed surgeries on male C57BL6/N mice at 9 weeks of age defining the aortic constriction by a 27G needle, thereby employing most frequently used methodological settings. The mice were randomly assigned into four separate groups, 6-0 silk, 7-0 silk, 6-0 prolene and 7-0 prolene (10 mice per group). Echocardiography was conducted before TAC and every 4 weeks thereafter to monitor the development of heart failure. Repeated measures correlation analysis was employed to compare disease progression among the different groups.

Results

Our findings reveal a significant influence of the chosen suture material on TAC outcomes. Mice operated with prolene showed increased mortality, slower body weight gain, faster left-ventricular mass increase, and a faster decline in left-ventricular ejection fraction, fractional shortening and aortic pressure gradient compared to silk-operated mice. Moreover, despite non significant, using thinner suture threads (7-0) tended to result in a more severe phenotype compared to thicker threads (6-0) across all tested parameters.

Discussion

Collectively, our results highlight the importance of suture material selection in determining the cardiac phenotype induced by TAC and emphasize the need to consider this factor when comparing data across different research laboratories.

Editorial of the Special Issue: Cellular Mechanisms of Cardiovascular Disease

Cardiovascular diseases (CVD) remain the major cause of mortality and disability worldwide, having contributed to 19 [...].

Neuregulin-1β Improves Uremic Cardiomyopathy and Renal Dysfunction in Rats

Chronic kidney disease is a global health problem affecting 10% to 12% of the population. Uremic cardiomyopathy is often characterized by left ventricular hypertrophy, fibrosis, and diastolic dysfunction. Dysregulation of neuregulin-1β signaling in the heart is a known contributor to heart failure. The systemically administered recombinant human neuregulin-1β for 10 days in our 5/6 nephrectomy-induced model of chronic kidney disease alleviated the progression of uremic cardiomyopathy and kidney dysfunction in type 4 cardiorenal syndrome. The currently presented positive preclinical data warrant clinical studies to confirm the beneficial effects of recombinant human neuregulin-1β in patients with chronic kidney disease.

The kisspeptin-1 receptor antagonist peptide-234 aggravates uremic cardiomyopathy in a rat model

Uremic cardiomyopathy is characterized by diastolic dysfunction, left ventricular hypertrophy (LVH), and fibrosis. Dysregulation of the kisspeptin receptor (KISS1R)-mediated pathways are associated with the development of fibrosis in cancerous diseases. Here, we investigated the effects of the KISS1R antagonist peptide-234 (P234) on the development of uremic cardiomyopathy. Male Wistar rats (300-350 g) were randomized into four groups: (i) Sham, (ii) chronic kidney disease (CKD) induced by 5/6 nephrectomy, (iii) CKD treated with a lower dose of P234 (ip. 13 µg/day), (iv) CKD treated with a higher dose of P234 (ip. 26 µg/day). Treatments were administered daily from week 3 for 10 days. At week 13, the P234 administration did not influence the creatinine clearance and urinary protein excretion. However, the higher dose of P234 led to reduced anterior and posterior wall thicknesses, more severe interstitial fibrosis, and overexpression of genes associated with left ventricular remodeling (Ctgf, Tgfb, Col3a1, Mmp9), stretch (Nppa), and apoptosis (Bax, Bcl2, Casp7) compared to the CKD group. In contrast, no significant differences were found in the expressions of apoptosis-associated proteins between the groups. Our results suggest that the higher dose of P234 hastens the development and pathophysiology of uremic cardiomyopathy by activating the fibrotic TGF-β-mediated pathways.

The Cytotoxic Properties of Extreme Fungi's Bioactive Components-An Updated Metabolic and Omics Overview

Fungi are the most diverse living organisms on planet Earth, where their ubiquitous presence in various ecosystems offers vast potential for the research and discovery of new, naturally occurring medicinal products. Concerning human health, cancer remains one of the leading causes of mortality. While extensive research is being conducted on treatments and their efficacy in various stages of cancer, finding cytotoxic drugs that target tumor cells with no/less toxicity toward normal tissue is a significant challenge. In addition, traditional cancer treatments continue to suffer from chemical resistance. Fortunately, the cytotoxic properties of several natural products derived from various microorganisms, including fungi, are now well-established. The current review aims to extract and consolidate the findings of various scientific studies that identified fungi-derived bioactive metabolites with antitumor (anticancer) properties. The antitumor secondary metabolites identified from extremophilic and extremotolerant fungi are grouped according to their biological activity and type. It became evident that the significance of these compounds, with their medicinal properties and their potential application in cancer treatment, is tremendous. Furthermore, the utilization of omics tools, analysis, and genome mining technology to identify the novel metabolites for targeted treatments is discussed. Through this review, we tried to accentuate the invaluable importance of fungi grown in extreme environments and the necessity of innovative research in discovering naturally occurring bioactive compounds for the development of novel cancer treatments.

Biotechnological Applications of Mushrooms under the Water-Energy-Food Nexus: Crucial Aspects and Prospects from Farm to Pharmacy

Mushrooms have always been an important source of food, with high nutritional value and medicinal attributes. With the use of biotechnological applications, mushrooms have gained further attention as a source of healthy food and bioenergy. This review presents different biotechnological applications and explores how these can support global food, energy, and water security. It highlights mushroom's relevance to meet the sustainable development goals of the UN. This review also discusses mushroom farming and its requirements. The biotechnology review includes sections on how to use mushrooms in producing nanoparticles, bioenergy, and bioactive compounds, as well as how to use mushrooms in bioremediation. The different applications are discussed under the water, energy, and food (WEF) nexus. As far as we know, this is the first report on mushroom biotechnology and its relationships to the WEF nexus. Finally, the review valorizes mushroom biotechnology and suggests different possibilities for mushroom farming integration.

Short-term toll-like receptor 9 inhibition leads to left ventricular wall thinning after myocardial infarction

AIMS

Ischaemia-reperfusion injury (IRI) following myocardial infarction remains a challenging topic in acute cardiac care and consecutively arising heart failure represents a severe long-term consequence. The extent of neutrophil infiltration and neutrophil-mediated cellular damage are thought to be aggravating factors enhancing primary tissue injury. Toll-like receptor 9 was found to be involved in neutrophil activation as well as chemotaxis and may represent a target in modulating IRI, aspects we aimed to illuminate by pharmacological inhibition of the receptor.

METHODS AND RESULTS

Forty-nine male adult Sprague-Dawley rats were used. IRI was induced by occlusion of the left coronary artery and subsequent snare removal after 30 min. Oligonucleotide (ODN) 2088, a toll-like receptor 9 (TLR9) antagonist, control-ODN, or DNase, were administered at the time of reperfusion and over 24 h via a mini-osmotic pump. The hearts were harvested 24 h or 4 weeks after left coronary artery occlusion and immunohistochemical staining was performed. Echocardiography was done after 1 and 4 weeks to determine ventricular function. Inhibition of TLR9 by ODN 2088 led to left ventricular wall thinning (P = 0.003) in association with drastically enhanced neutrophil infiltration (P = 0.005) and increased markers of tissue damage. Additionally, an up-regulation of the chemotactic receptor CXCR2 (P = 0.046) was found after TLR9 inhibition. No such effects were observed in control-ODN or DNase-treated animals. We did not observe changes in monocyte content or subset distribution, hinting towards neutrophils as the primary mediators of the exerted tissue injury.

CONCLUSIONS

Our data indicate a TLR9-dependent, negative regulation of neutrophil infiltration. Blockage of TLR9 appears to prevent the down-regulation of CXCR2, followed by an uncontrolled migration of neutrophils towards the area of infarction and the exertion of disproportional tissue injury resulting in potential aneurysm formation. In comparison with previous studies conducted in TLR^-/- mice, we deliberately chose a transient pharmacological inhibition of TLR9 to highlight effects occurring in the first 24 h following IRI.

Inflammasome Activity in the Skeletal Muscle and Heart of Rodent Models for Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is characterized by wasting of muscles that leads to difficulty moving and premature death, mainly from heart failure. Glucocorticoids are applied in the management of the disease, supporting the hypothesis that inflammation may be driver as well as target. However, the inflammatory mechanisms during progression of cardiac and skeletal muscle dysfunction are still not well characterized. Our objective was to characterize the inflammasomes in myocardial and skeletal muscle in rodent models of DMD. Gastrocnemius and heart samples were collected from mdx mice and DMDmdx rats (3 and 9-10 months). Inflammasome sensors and effectors were assessed by immunoblotting. Histology was used to assess leukocyte infiltration and fibrosis. In gastrocnemius, a tendency towards elevation of gasdermin D irrespective of the age of the animal was observed. The adaptor protein was elevated in the mdx mouse skeletal muscle and heart. Increased cleavage of the cytokines was observed in the skeletal muscle of the DMDmdx rats. Sensor or cytokine expression was not changed in the tissue samples of the mdx mice. In conclusion, inflammatory responses are distinct between the skeletal muscle and heart in relevant models of DMD. Inflammation tends to decrease over time, supporting the clinical observations that the efficacy of anti-inflammatory therapies might be more prominent in the early stage.

Ivabradine acutely improves cardiac Ca handling and function in a rat model of Duchenne muscular dystrophy

The muscular dystrophies caused by dystrophin deficiency, the so-called dystrophinopathies, are associated with impaired cardiac contractility and arrhythmias, which considerably contribute to disease morbidity and mortality. Impaired Ca handling in ventricular cardiomyocytes has been identified as a causative factor for complications in the dystrophic heart, and restoration of normal Ca handling in myocytes has emerged as a promising new therapeutic strategy. In the present study, we explored the hypothesis that ivabradine, a drug clinically approved for the treatment of heart failure and stable angina pectoris, improves Ca handling in dystrophic cardiomyocytes and thereby enhances contractile performance in the dystrophic heart. Therefore, ventricular cardiomyocytes were isolated from the hearts of adult dystrophin-deficient DMD^mdx rats, and the effects of acutely applied ivabradine on intracellular Ca transients were tested. In addition, the drug's acute impact on cardiac function in DMD^mdx rats was assessed by transthoracic echocardiography. We found that administration of ivabradine to DMD^mdx rats significantly improved cardiac function. Moreover, the amplitude of electrically induced intracellular Ca transients in ventricular cardiomyocytes isolated from DMD^mdx rats was increased by the drug. We conclude that ivabradine enhances Ca release from the sarcoplasmic reticulum in dystrophic cardiomyocytes and thereby improves contractile performance in the dystrophic heart.

Corrigendum: Mapping the functional anatomy and topography of the cardiac autonomic innervation for selective cardiac neuromodulation using MicroCT

[This corrects the article DOI: 10.3389/fcell.2022.968870.].

Predicting and Comparing Students’ Online and Offline Academic Performance Using Machine Learning Algorithms

Due to COVID-19, the researching of educational data and the improvement of related systems have become increasingly important in recent years. Educational institutions seek more information about their students to find ways to utilize their talents and address their weaknesses. With the emergence of e-learning, researchers and programmers aim to find ways to maintain students’ attention and improve their chances of achieving a higher grade point average (GPA) to gain admission to their desired colleges. In this paper, we predict, test, and provide reasons for declining student performance using various machine learning algorithms, including support vector machine with different kernels, decision tree, random forest, and k-nearest neighbors algorithms. Additionally, we compare two databases, one with data related to online learning and another with data on relevant offline learning properties, to compare predicted weaknesses with metrics such as F1 score and accuracy. However, before applying the algorithms, the databases need normalization to meet the prediction format. Ultimately, we find that success in school is related to habits such as sleep, study time, and screen time. More details regarding the results are provided in this paper.

A novel ex-vivo isolated rabbit heart preparation to explore the cardiac effects of cervical and cardiac vagus nerve stimulation

The cardiac responses to vagus nerve stimulation (VNS) are still not fully understood, partly due to uncontrollable confounders in the in-vivo experimental condition. Therefore, an ex-vivo Langendorff-perfused rabbit heart with intact vagal innervation is proposed to study VNS in absence of cofounding anesthetic or autonomic influences. The feasibility to evoke chronotropic responses through electrical stimulation ex-vivo was studied in innervated isolated rabbit hearts (n = 6). The general nerve excitability was assessed through the ability to evoke a heart rate (HR) reduction of at least 5 bpm (physiological threshold). The excitability was quantified as the charge needed for a 10-bpm HR reduction. The results were compared to a series of in-vivo experiments rabbits (n = 5). In the ex-vivo isolated heart, the baseline HR was about 20 bpm lower than in-vivo (158 ± 11 bpm vs 181 ± 19 bpm). Overall, the nerve remained excitable for about 5 h ex-vivo. The charges required to reduce HR by 5 bpm were 9 ± 6 µC and 549 ± 370 µC, ex-vivo and in-vivo, respectively. The charges needed for a 10-bpm HR reduction, normalized to the physiological threshold were 1.78 ± 0.8 and 1.22 ± 0.1, in-vivo and ex-vivo, respectively. Overall, the viability of this ex-vivo model to study the acute cardiac effects of VNS was demonstrated.

An Elastic Self-Adjusting Technique for Rare-Class Synthetic Oversampling Based on Cluster Distortion Minimization in Data Stream

Adaptive machine learning has increasing importance due to its ability to classify a data stream and handle the changes in the data distribution. Various resources, such as wearable sensors and medical devices, can generate a data stream with an imbalanced distribution of classes. Many popular oversampling techniques have been designed for imbalanced batch data rather than a continuous stream. This work proposes a self-adjusting window to improve the adaptive classification of an imbalanced data stream based on minimizing cluster distortion. It includes two models; the first chooses only the previous data instances that preserve the coherence of the current chunk's samples. The second model relaxes the strict filter by excluding the examples of the last chunk. Both models include generating synthetic points for oversampling rather than the actual data points. The evaluation of the proposed models using the Siena EEG dataset showed their ability to improve the performance of several adaptive classifiers. The best results have been obtained using Adaptive Random Forest in which Sensitivity reached 96.83% and Precision reached 99.96%.

Overlapping and Distinct Features of Cardiac Pathology in Inherited Human and Murine Ether Lipid Deficiency

Inherited deficiency in ether lipids, a subgroup of glycerophospholipids with unique biochemical and biophysical properties, evokes severe symptoms in humans resulting in a multi-organ syndrome. Mouse models with defects in ether lipid biosynthesis have widely been used to understand the pathophysiology of human disease and to study the roles of ether lipids in various cell types and tissues. However, little is known about the function of these lipids in cardiac tissue. Previous studies included case reports of cardiac defects in ether-lipid-deficient patients, but a systematic analysis of the impact of ether lipid deficiency on the mammalian heart is still missing. Here, we utilize a mouse model of complete ether lipid deficiency (Gnpat KO) to accomplish this task. Similar to a subgroup of human patients with rhizomelic chondrodysplasia punctata (RCDP), a fraction of Gnpat KO fetuses present with defects in ventricular septation, presumably evoked by a developmental delay. We did not detect any signs of cardiomyopathy but identified increased left ventricular end-systolic and end-diastolic pressure in middle-aged ether-lipid-deficient mice. By comprehensive electrocardiographic characterization, we consistently found reduced ventricular conduction velocity, as indicated by a prolonged QRS complex, as well as increased QRS and QT dispersion in the Gnpat KO group. Furthermore, a shift of the Wenckebach point to longer cycle lengths indicated depressed atrioventricular nodal function. To complement our findings in mice, we analyzed medical records and performed electrocardiography in ether-lipid-deficient human patients, which, in contrast to the murine phenotype, indicated a trend towards shortened QT intervals. Taken together, our findings demonstrate that the cardiac phenotype upon ether lipid deficiency is highly heterogeneous, and although the manifestations in the mouse model only partially match the abnormalities in human patients, the results add to our understanding of the physiological role of ether lipids and emphasize their importance for proper cardiac development and function.

Methylation of the Hippo effector YAP by the methyltransferase SETD7 drives myocardial ischaemic injury: a translational study

AIMS

Methylation of non-histone proteins is emerging as a central regulatory mechanism in health and disease. The methyltransferase SETD7 has shown to methylate and alter the function of a variety of proteins in vitro; however, its function in the heart is poorly understood. The present study investigates the role of SETD7 in myocardial ischaemic injury.

METHODS AND RESULTS

Experiments were performed in neonatal rat ventricular myocytes (NRVMs), SETD7 knockout mice (SETD7-/-) undergoing myocardial ischaemia/reperfusion (I/R) injury, left ventricular (LV) myocardial samples from patients with ischaemic cardiomyopathy (ICM), and peripheral blood mononuclear cells (PBMCs) from patients with ST-elevation MI (STEMI). We show that SETD7 is activated upon energy deprivation in cultured NRVMs and methylates the Hippo pathway effector YAP, leading to its cytosolic retention and impaired transcription of antioxidant genes manganese superoxide dismutase (MnSOD) and catalase (CAT). Such impairment of antioxidant defence was associated with mitochondrial reactive oxygen species (mtROS), organelle swelling, and apoptosis. Selective pharmacological inhibition of SETD7 by (R)-PFI-2 restored YAP nuclear localization, thus preventing mtROS, mitochondrial damage, and apoptosis in NRVMs. In mice, genetic deletion of SETD7 attenuated myocardial I/R injury, mtROS, and LV dysfunction by restoring YAP-dependent transcription of MnSOD and CAT. Moreover, in cardiomyocytes isolated from I/R mice and ICM patients, (R)-PFI-2 prevented mtROS accumulation, while improving Ca2+-activated tension. Finally, SETD7 was up-regulated in PBMCs from STEMI patients and negatively correlated with MnSOD and CAT.

CONCLUSION

We show a methylation-dependent checkpoint regulating oxidative stress during myocardial ischaemia. SETD7 inhibition may represent a valid therapeutic strategy in this setting.

Von Willebrand Factor and Platelet Levels before Conditioning Chemotherapy Indicate Bone Marrow Regeneration following Autologous Hematopoietic Stem Cell Transplantation

Autologous hematopoietic stem cell transplantation (HSCT) is often complicated by hemostatic and thrombotic events associated with endothelial cell injury. Thrombotic complications are affected by a disturbed balance between platelets, circulating von Willebrand factor (VWF), and its specific protease, ADAMTS13. HSCT-associated endothelial dysfunction, impaired hemostasis, and inflammation are interrelated processes, and research on the complex interplay of conditioning regimens from engraftment to bone marrow regeneration remains intensive. This prospective observational study comparing lymphoma and multiple myeloma (MM) patients who underwent autologous HSCT explored how platelet count, VWF level, ADAMTS13 activity, and C-reactive protein (CRP) level as potential markers (1) vary in response to therapy, (2) differ between the 2 groups, and (3) correlate with the remission state at 100 days after HSCT. We correlated the quantitative changes in platelet count and levels of VWF, ADAMTS13, and CRP with one another during HSCT and in the remission state in 45 patients with lymphoma and 59 patients with MM who underwent autologous HSCT between 2010 and 2013 at the University of Debrecen. Samples were collected at the start of conditioning chemotherapy, on the day of stem cell transplantation, and at 5, 11, and 100 days following HSCT. CRP levels peaked when platelet counts dropped to a minimum, and these changes were much more pronounced in the lymphoma group. VWF level was the highest, with lower ADAMTS13 activity, at platelet engraftment in both patient groups equally. Diagnostic evidence indicative of thrombotic complications was not found. In the lymphoma group, VWF level prior to conditioning had statistically significant correlations with platelet count, CRP level, and hemoglobin concentration at the time of bone marrow regeneration (P < .001) and during the remission state (P = .034). In the MM group, platelet count before conditioning was correlated with platelet count (P < .001) and white blood cell count (P = .012) at the time of bone marrow regeneration. The statistically significant correlation of the markers at the time of bone marrow regeneration with the preconditioning VWF levels in lymphoma and with the preconditioning platelet counts in MM might indicate the clinical significance of the bone marrow niches of arterioles and megakaryocytes, respectively, where the stem cells are located and regulated. Because preconditioning VWF levels are associated with remission after HSCT in lymphoma patients, VWF should be screened before conditioning, along with the markers used in HSCT protocols, to optimize personalized treatment and reduce therapeutic risks.

Biochemical and Transcriptional Responses in Cold-Acclimated and Non-Acclimated Contrasting Camelina Biotypes under Freezing Stress

Cold-acclimated and non-acclimated contrasting Camelina (Camelina sativa L.) biotypes were investigated for changes in stress-associated biomarkers, including antioxidant enzyme activity, lipid peroxidation, protein, and proline content. In addition, a well-known freezing tolerance pathway participant known as C-repeat/DRE-binding factors (CBFs), an inducer of CBF expression (ICE1), and a cold-regulated (COR6.6) genes of the ICE-CBF-COR pathway were studied at the transcriptional level on the doubled-haploid (DH) lines. Freezing stress had significant effects on all studied parameters. The cold-acclimated DH34 (a freezing-tolerant line) showed an overall better performance under freezing stress than non-acclimated plants. The non-cold-acclimated DH08 (a frost-sensitive line) showed the highest electrolyte leakage after freezing stress. The highest activity of antioxidant enzymes (glutathione peroxidase, superoxide dismutase, and catalase) was also detected in non-acclimated plants, whereas the cold-acclimated plants showed lower enzyme activities upon stress treatment. Cold acclimation had a significantly positive effect on the total protein and proline content of stressed plants. The qRT-PCR analysis revealed significant differences in the expression and cold-inducibility of CsCBF1-3, CsICE1, and CsCOR6.6 genes among the samples of different treatments. The highest expression of all CBF genes was recorded in the non-acclimated frost-tolerant biotype after freezing stress. Interestingly a significantly higher expression of COR6.6 was detected in cold-acclimated samples of both frost-sensitive and -tolerant biotypes after freezing stress. The presented results provide more insights into freezing tolerance mechanisms in the Camelina plant from both a biochemical point of view and the expression of the associated genes.

Similarity-Based Adaptive Window for Improving Classification of Epileptic Seizures with Imbalance EEG Data Stream

Data stream mining techniques have recently received increasing research interest, especially in medical data classification. An unbalanced representation of the classification's targets in these data is a common challenge because classification techniques are biased toward the major class. Many methods have attempted to address this problem but have been exaggeratedly biased toward the minor class. In this work, we propose a method for balancing the presence of the minor class within the current window of the data stream while preserving the data's original majority as much as possible. The proposed method utilized similarity analysis for selecting specific instances from the previous window. This group of minor-class was then added to the current window's instances. Implementing the proposed method using the Siena dataset showed promising results compared to the Skew ensemble method and some other research methods.

Closed-loop vagus nerve stimulation for heart rate control evaluated in the Langendorff-perfused rabbit heart

Persistent sinus tachycardia substantially increases the risk of cardiac death. Vagus nerve stimulation (VNS) is known to reduce the heart rate, and hence may be a non-pharmacological alternative for the management of persistent sinus tachycardia. To precisely regulate the heart rate using VNS, closed-loop control strategies are needed. Therefore, in this work, we developed two closed-loop VNS strategies using an in-silico model of the cardiovascular system. Both strategies employ a proportional-integral controller that operates on the current amplitude. While one control strategy continuously delivers stimulation pulses to the vagus nerve, the other applies bursts of stimuli in synchronization with the cardiac cycle. Both were evaluated in Langendorff-perfused rabbit hearts (n = 6) with intact vagal innervation. The controller performance was quantified by rise time (T_r), steady-state error (SSE), and percentual overshoot amplitude (%OS). In the ex-vivo setting, the cardiac-synchronized variant resulted in T_r = 10.7 ± 4.5 s, SSE = 12.7 ± 9.9 bpm and %OS = 5.1 ± 3.6% while continuous stimulation led to T_r = 10.2 ± 5.6 s, SSE = 10 ± 6.7 bpm and %OS = 3.2 ± 1.9%. Overall, both strategies produced a satisfying and reproducible performance, highlighting their potential use in persistent sinus tachycardia.

Membrane Clustering of Coronavirus Variants Using Document Similarity

Currently, as an effect of the COVID-19 pandemic, bioinformatics, genomics, and biological computations are gaining increased attention. Genomes of viruses can be represented by character strings based on their nucleobases. Document similarity metrics can be applied to these strings to measure their similarities. Clustering algorithms can be applied to the results of their document similarities to cluster them. P systems or membrane systems are computation models inspired by the flow of information in the membrane cells. These can be used for various purposes, one of them being data clustering. This paper studies a novel and versatile clustering method for genomes and the utilization of such membrane clustering models using document similarity metrics, which is not yet a well-studied use of membrane clustering models.

A methylation-dependent checkpoint by SETD7 promotes myocardial ischemic injury in mice and men

Background

Despite appropriate revascularization strategies, a significant number of patients with myocardial infarction (MI) develop ischemic heart failure suggesting that breakthrough therapies are yet to be approved in this setting. Methylation of non-histone proteins is emerging as a central regulatory mechanism in health and disease. The methyltransferase SETD7 has been shown to methylate and alter the function of a variety of proteins in vitro, however, its function in the heart is poorly understood.

Purpose

To determine the role of SETD7 in myocardial ischemic injury.

Methods

Neonatal rat ventricular myocytes (NRVM) were exposed to normal glucose levels or glucose deprivation (GD) for 15 h, in the presence of the selective SETD7 inhibitor (R)-PFI-2 or its inactive enantiomer (S)-PFI-2. Western blot and real-time PCR were employed to investigate the effects of energy stress on SETD7 and the Hippo pathway, while apoptosis and oxidative stress were assessed by Caspase-3 activity assay and mitoSOX staining. YAP transcriptional activity was assessed by chromatin immunoprecipitation assay (ChIP) while its localization and methylation were examined by confocal microscopy and immunoblotting, respectively. SETD7 knockout (SETD7−/−) mice and wild-type (WT) littermates underwent myocardial ischemia-reperfusion (I/R) injury (1h coronary ligation /24 h of reperfusion) followed by assessment of cardiac function by echocardiography. Left ventricular (LV) myocardial samples were collected from I/R mice and patients with ischemic cardiomyopathy (ICM), and isolated cardiomyocytes were treated with (R)-PFI-2. Finally, SETD7 expression was also assessed in peripheral blood mononuclear cells (PBMCs) from patients with ST-elevation MI (STEMI).

Results

SETD7 was activated upon energy deprivation in cultured NRVMs and methylated YAP, leading to its cytosolic retention and impaired transcription of antioxidant genes MnSOD and CAT. Pharmacological inhibition of SETD7 by (R)-PFI-2 restored YAP nuclear localization thus preventing mitochondrial reactive oxygen species (mtROS) and apoptosis. SETD7 deletion in mice attenuated I/R injury, mtROS and LV dysfunction by restoring YAP-dependent transcriptional programs. SETD7/YAP dysregulation was also observed in LV specimens from ICM patients. Moreover, in cardiomyocytes isolated from I/R mice and ICM patients, (R)-PFI-2 restored YAP nuclear localization, prevented mtROS accumulation while improving myofibrillar protein contractility and Ca2+ sensitivity. Finally, SETD7 was upregulated in PBMCs from STEMI patients and negatively correlated with the expression of MnSOD and CAT.

Conclusions

SETD7-dependent methylation of YAP is an important mechanism underpinning myocardial oxidative stress and apoptosis during ischemia. Pharmacological modulation of SETD7 by (R)-PFI-2 may represent a potential therapeutic approach to prevent myocardial ischemic damage through modulation of the Hippo pathway.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): University of Zurich

Extension of fitness evaluations with muscle oxygen saturation measurements based on near-infrared spectroscopy analysis during cardiopulmonary exercise testing in elite athletes

Introduction

Many cardiovascular parameters of sport adaptation have become an area of detailed research in recent decades. However, details of local circulatory and metabolic processes ongoing in the working muscles during physical exercise need to be revealed.

Purpose

Our aim was to extend cardiopulmonary exercise testing with near-infrared spectroscopy measurements to focus on observing local changes in the contracting muscles during running.

Methods

Mixed muscle oxygen saturation values (SmO2) measured in the left vastus lateralis muscle of athletes were analyzed by near-infrared spectroscopy during vita maxima treadmill cardiopulmonary exercise testing with 2-min fingertip lactate measurements. Body composition analysis was carried out with bioimpedance method. One-way repeated measures ANOVA, Tukey post-hoc test, Shapiro–Wilk test and Pearson correlation were used for statistical analysis.

Results

The results of 66 elite athletes (male: 40; age: 17.9±3.6 y; training: 17.7±6.6 h/w; water polo player: 56, wrestler: 8, basketball player: 2) were analyzed. The 10-second averaged values of the measured saturation values were examined at rest (65.8±11.1%), at the anaerobic threshold (40.7±22.8%), at maximum load (30.2±20.5%) and after 5 minutes of cool-down (70.9±12.8%). Significant differences were measured between the four measurement time points in all pairings. A negative correlation was found between the achieved maximal oxygen uptake and the muscle oxygen saturation values measured at the anaerobic threshold and at the maximal load (respectively r=−0.30, p&lt;0.02; r=−0.32, p&lt;0.01). Oxygen uptake at the end of cool-down was also negatively correlated with muscle oxygen saturation values measured at the anaerobic threshold and at the peak of exercise (respectively r=−0.27, p&lt;0.05; r=−0.27, p&lt;0.05). The fat-free mass of the identical limb showed negative correlation with the muscle oxygen saturation values measured at the anaerobic threshold, at the maximal load and at the cool-down (respectively r=−0.43, p&lt;0.01; r=−0.44, p&lt;0.01; r=−0.35, p&lt;0.01), while positive interactions were observed between the body-fat mass of the same limb and the muscle oxygen saturation values (respectively r=0.51, p&lt;0.01; r=0.55, p&lt;0.01; r=0.41, p&lt;0.01). Muscle oxygen saturation values showed no significant correlations with exercise time, lactate levels, or heart rate measurements.

Conclusions

By our results, muscle oxygen saturation measurements can be reliably applied during exercise physiological measurements. During exercise, muscle oxygen saturation values negatively correlated with oxygen uptake. At the cool-down phase, a rebound effect could be observed compared to the resting measurements. On the identical limb, the higher the muscle mass was, the higher muscle desaturation could be measured. This easy-to-perform test provides insight into muscle metabolism processes and can help with training planning and athlete follow-up.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This project was supported by a grant from the National Research, Development and Innovation Office (NKFIH) of Hungary (K 135076). Supported by the ÚNKP-21-3-I-SE-68 New National Excellence Program of the Ministry for Innovation and Technology from the Source of the National Research, Development and Innovation fund.

Increased Tenascin-C expression contributes to cardiac dysfunction and fibrosis in Duchenne muscular dystrophy

Introduction and aims

Cardiac fibrosis is characterized by the net accumulation of extracellular matrix (ECM) proteins in the cardiac interstitium and contributes to cardiac contractile dysfunction. In Duchenne muscular dystrophy (DMD), cardiomyopathy develops as a result of a dystrophin deficiency causing fibrofatty replacement of the myocardium, however the underlying mechanisms are not fully understood. There is a growing collection of evidence that ECM proteins, including Tenascin C (TN-C), plays a maladaptive role in left ventricular (LV) remodelling and cardiac fibrosis in ischemic heart disease. The aims of our study were 1) to assess TN-C levels, fibrosis and cardiac dysfunction in DMD patients, and 2) to clarify the role of TN-C in cardiovascular dysfunction and fibrosis using male mdx (n=10) and mdx TN-C KO mice (n=8).

Results

In male patients with DMD (n=18) and age matched controls (n=12) undergoing cardiac MRI, we detected greater myocardial fibrosis than in control hearts. In addition, we observed an elevation of TN-C plasma levels [median concentration (3.55); interquartile range (0.61–7.43) ng/mL] in DMD patients, and its expression negatively correlated to LV ejection fraction (EF) [median LVEF (45); interquartile range (37.5–51.5) %]. Male wt, mdx and mdx TN-C KO age-matched (10 months) mice were used. Transthoracic echocardiography was performed and fibrosis was assessed on cardiac tissue sections. Wire myography was used to assess vascular endothelial function. To explore the signalling pathways contributing to cardiac fibrosis, human cardiac fibroblasts (hCFs) were treated with recombinant human TN-C or TGF-β and gene expression and epigenetic regulation of NF-kB/p65 were assessed. Mdx mice showed significantly increased cardiac fibrosis which was accompanied with markedly elevated TN-C level in cardiac tissue and plasma compared to wt animals (p&lt;0.05, respectively). Moreover, TN-C level in plasma correlated positively with the degree of cardiac dilation in dystrophic mice. In addition, vascular endothelial function was notably impaired in mdx mice. In contrast, we observed preserved vascular function in mdx- TN-C KO mice, this was accompanied by a significant reduction in cardiac fibrosis in compared to age-matched mdx mice (p&lt;0.05, respectively). hCFs treated with TN-C or TGF-β showed increased collagen and α-SMA expressions which could be prevented by application of siRNA against TN-C. In addition, both TN-C and TGF-β caused p65/NF-κB promoter demethylation and subsequently triggered pro-inflammatory and pro-fibrotic signalling, which could be reversed by applying p38 MAPK inhibitor in hCFs.

Conclusion

TN-C is a critical component of cardiac fibrosis and cardiac dysfunction in DMD. The activation of NF-κB p65 signalling pathway may play a role in TN-C induced fibrosis. Thus, TN-C may be a mediator and potential target for therapy in DMD-associated cardiovascular complications.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Österreichische MuskelforschungFWF - Austrian Science Found P 35878

Agomir of miRNA-30d – a potential new therapeutic target for prevention of ischemic cardiomyopathy after myocardial infarction?

Background

MicroRNA (miR)-30d is not only a valuable biomarker for assessing the extent of cardiac remodeling after myocardial infarction (MI), but also an important predictor of clinical outcome in heart failure. Overexpression of miRNA-30d appears to have a cardioprotective effect by preventing cardiomyocyte apoptosis as well as averting cardiac fibroblast proliferation via multiple molecular pathways. The aim of the present in vivo and in vitro study was to demonstrate whether an miR-30d can be a potential therapeutic target to reduce the risk of ischemic cardiomyopathy (iCMP) after MI.

Methods

First of all, miRNA profiling was performed by next generation sequencing (NGS) to assess differences in miRNA expression in ischemic vs. healthy myocardium in a rat model of MI using coronary artery ligation (ischemia/reperfusion injury, IR). MiR-30d was selected as the most promising target as it was significantly downregulated in ischemic myocardium and can be upregulated by cardioprotective agents. Therefore, an agomir of miR-30d was administered in the respective treatment group intraperitoneally, whereas non-functional, scrambled miRNA was administered in the control group. To analyze the ratio between phosphorylated p53 (pp53) and total p53, apoptosis was evaluated in human cardiomyocytes using a p53 and pp53 ELISA kit. To gain indirect insight into infarct healing, scratch assays were used to obtain information on cell migration in human umbilical vein endothelial cells (HUVEC) in vitro. Six weeks after the in vivo induction of acute MI/IR with consequential iCMP in a rat model, the extent of MI was evaluated by planimetry.

Results

The majority of miRNAs studied here showed significant up-regulation in the MI-induced heart tissue in comparison to the sham operated controls. In contrast, miRNA-30d was highly significantly reduced (p&lt;0.001). Based on these investigations and the already repeatedly documented cardioprotective effect of miR-30d overexpression, an agomir was selected as a potential therapy target. Human cardiomyocytes under the influence of an agomir of miR-30d showed a decreased pp53/total p53 ratio (0.66±0.09 vs. 0.81±0.19) and thus a distinct tendency (p=0.055) for a reduction in apoptotic rate compared to the control group. In HUVECs, gap closure was significantly faster in the agomir treated cells 20h and 26h post-scratching (19.1% more than scrambled control after 20h; p=0.0028 and 18.7% more than scrambled control after 26h; p=0.0081). In the in vivo model, infarct size of left ventricle was significantly reduced by using the agomir (7.43±4.13% vs. 12.76±4.76%; p=0.0172).

Conclusion

Using an agomir of miR-30d underlines the cardioprotective effects of miR-30d in MIR/IR and could reduce the risk for iCMP development. Further investigations regarding its therapeutic potential in the human should be considered, as microRNA treatments are gaining more and more clinical applicability today.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Paracelsus Medical University, PMU-FFF

Mapping the functional anatomy and topography of the cardiac autonomic innervation for selective cardiac neuromodulation using MicroCT

Background: Vagus nerve stimulation (VNS) has gained great importance as a promising therapy for a myriad of diseases. Of particular interest is the therapy of cardiovascular diseases, such as heart failure or atrial fibrillation using selective cardiac VNS. However, there is still a lack of organ-specific anatomical knowledge about the fascicular anatomy and topography of the cardiac branch (CB), which diminishes the therapeutic possibilities for selective cardiac neuromodulation. Here, we established a topographical and anatomical map of the superior cardiac VN in two animal species to dissect cervical and cardiac VN morphology.

Methods: Autonomic nerves including superior CBs were harvested from domestic pigs and New Zeeland rabbits followed by imaging with microcomputed tomography (µCT) and 3D rendering. The data were analyzed in terms of relevant topographical and anatomical parameters.

Results: Our data showed that cardiac vagal fascicles remained separated from other VN fascicles up to 22.19 mm (IQR 14.02–41.30 mm) in pigs and 7.68 mm (IQR 4.06–12.77 mm) in rabbits from the CB point and then started merging with other fascicles. Exchanges of nerve fascicles between sympathetic trunk (ST) and VN were observed in 3 out of 11 nerves, which might cause additional unwanted effects in unselective VNS. Our 3D rendered digital model of the cardiac fascicles was generated showing that CB first remained on the medial side where it branched off the VN, as also shown in the µCT data of 11 pig nerves, and then migrated towards the ventromedial site the further it was traced cranially.

Conclusion: Our data provided an anatomical map of the cardiac vagal branches including cervical VN and ST for future approaches of selective cardiac neurostimulation, indicating the best position of selective cardiac VNS just above the CB point.

A new Kirkpatrick-Baez-based scanning microscope for the Submicron Resolution X-ray Spectroscopy (SRX) beamline at NSLS-II

The development, construction, and first commissioning results of a new scanning microscope installed at the 5-ID Submicron Resolution X-ray Spectroscopy (SRX) beamline at NSLS-II are reported. The developed system utilizes Kirkpatrick-Baez mirrors for X-ray focusing. The instrument is designed to enable spectromicroscopy measurements in 2D and 3D with sub-200 nm spatial resolution. The present paper focuses on the design aspects, optical considerations, and specifics of the sample scanning stage, summarizing some of the initial commissioning results.

Mid-Infrared Imaging Characterization to Differentiate Lung Cancer Subtypes

Introduction: Lung cancer is the most common malignancy worldwide. Squamous cell carcinoma (SQ) and adenocarcinoma (LUAD) are the two most frequent histological subtypes. Small cell carcinoma (SCLC) subtype has the worst prognosis. Differential diagnosis is essential for proper oncological treatment. Life science associated mid- and near-infrared based microscopic techniques have been developed exponentially, especially in the past decade. Vibrational spectroscopy is a potential non-destructive approach to investigate malignancies.

Aims: Our goal was to differentiate lung cancer subtypes by their label-free mid-infrared spectra using supervised multivariate analyses.

Material and Methods: Formalin-fixed paraffin-embedded (FFPE) samples were selected from the archives. Three subtypes were selected for each group: 10-10 cases SQ, LUAD and SCLC. 2 μm thick sections were cut and laid on aluminium coated glass slides. Transflection optical setup was applied on Perkin-Elmer infrared microscope. 250 × 600 μm areas were imaged and the so-called mid-infrared fingerprint region (1800-648cm⁻¹) was further analysed with linear discriminant analysis (LDA) and support vector machine (SVM) methods.

Results: Both “patient-based” and “pixel-based” approaches were examined. Patient-based analysis by using 3 LDA models and 2 SVM models resulted in different separations. The higher the cut-off value the lower is the accuracy. The linear C-support vector classification (C-SVC) SVM resulted in the best (100%) accuracy for the three subtypes using a 50% cut-off value. The pixel-based analysis gave, similarly, the linear C-SVC SVM model to be the most efficient in the statistical indicators (SQ sensitivity 81.65%, LUAD sensitivity 82.89% and SCLC sensitivity 88.89%). The spectra cut-off, the kernel function and the algorithm function influence the accuracy.

Conclusion: Mid-Infrared imaging could be used to differentiate FFPE lung cancer subtypes. Supervised multivariate tools are promising to accurately separate lung tumor subtypes. The long-term perspective is to develop a spectroscopy-based diagnostic tool, revolutionizing medical differential diagnostics, especially cancer identification.

Normothermic blood polarizing versus depolarizing cardioplegia in a porcine model of cardiopulmonary bypass

OBJECTIVES

We have previously demonstrated beneficial cardiac protection with hypothermic polarizing cardioplegia compared to a hyperkalemic depolarizing cardioplegia. In this study, a porcine model of cardiopulmonary bypass was used to compare the protective effects of normothermic blood-based polarizing and depolarizing cardioplegia during cardiac arrest.

METHODS

Thirteen pigs were randomized to receive either normothermic polarizing (n = 8) or depolarizing (n = 5) blood-based cardioplegia. After initiation of cardiopulmonary bypass, normothermic arrest (34°C, 60 min) was followed by 60 min of on-pump and 90 min of off-pump reperfusion. Primary outcome was myocardial injury measured as arterial myocardial creatine kinase concentration. Secondary outcome was haemodynamic function and the energy state of the hearts.

RESULTS

During reperfusion, release of myocardial creatine kinase was comparable between groups (P = 0.36). In addition, most haemodynamic parameters showed comparable results between groups, but stroke volume (P = 0.03) was significantly lower in the polarizing group. Adenosine triphosphate levels were significantly (18.41 ± 3.86 vs 22.97 ± 2.73 nmol/mg; P = 0.03) lower in polarizing hearts, and the requirement for noradrenaline administration (P = 0.002) and temporary pacing (6 vs 0; P = 0.02) during reperfusion were significantly higher in polarizing hearts.

CONCLUSIONS

Under normothermic conditions, polarizing blood cardioplegia was associated with similar myocardial injury to depolarizing blood cardioplegia. Reduced haemodynamic and metabolic outcome and a higher need for temporary pacing with polarized arrest may be associated with the blood-based dilution of this solution.

Ivabradine rescues vascular abnormalities in a mouse model of duchenne muscular dystrophy

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Fonds zur Förderung der wissenschaftlichen Forschung

Ivabradine rescues vascular abnormalities in a mouse model of muscular dystrophy

Background

Duchenne muscular dystrophy (DMD) is a rare genetic disorder that primarily affects boys, initiated by the absence of dystrophin and is mainly differentiated by skeletal muscle degeneration and cardiac dysfunction. However, recent studies have underlined the importance of vascular abnormalities such as augmented arterial stiffness and endothelial dysfunction in the progression of cardiac complications in DMD. Several pleiotropic effects of ivabradine have been identified, including the reduction of vascular complications in coronary artery and ischemic heart disease patients. Nevertheless, whether chronic ivabradine treatment could improve the vascular complications in DMD is largely unknown.

Methods

In this study, vascular abnormalities in both dystrophin and utrophin deficient (mdx-utr KO) mice were examined, a severe and progressive animal model of DMD. Mice (4-6 weeks old) were subjected to ivabradine (10 mg/kg/day in drinking water) or vehicle treatments for 3 to 4 weeks. At the end of the treatment, aorta and lung tissue were collected to assess the vascular reactivity by wire myograph and the activity of angiotensin-converting enzyme (ACE) activity was measured in lung tissue respectively.

Results

Comparable with DMD patients, mdx-utr KO mice also exhibit vascular abnormalities and cardiac fibrosis. Ivabradine-treated mice showed a significantly improved endothelium-dependent vasodilation (p&lt;0.05) and decreased vascular stiffness compared to vehicle-treated animals (p&lt;0.01). In addition, lung ACE activity was significantly reduced in the treated mice in comparison to the control group (p&lt;0.01) indicating less activation in the renin-angiotensin-aldosterone system, which causative plays role in the progression of vascular and cardiac dysfunction.

Conclusions

In conclusion, our study shows for the first time the beneficial effects of chronic ivabradine treatment on the progression of cardiac vascular complications in DMD and this may present a novel therapeutic approach. Further studies are needed to clarify the underling signalling mechanisms.

Topographical Mapping of the cardiac autonomic innervation for selective cardiac neuromodulation in pigs and rabbits using MicroCT

Funding Acknowledgements

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): Horizon 2020- EU H2020-EU.1.2.2. - FET Proactive

"NeuHeart" Nr. 824071

Background & Introduction

In recent years, Vagus Nerve Stimulation (VNS) has proved to be a potential therapeutic approach for the treatment of cardiovascular diseases, such as Heart Failure or atrial fibrillation [1]. However, the lack of specific anatomical knowledge of the cervical VN [2, 3] and thus, of the cardiac autonomic innervation aggravates the side effects of unselective cervical VNS.

Purpose

The goal of this study was to investigate the cardiac vagus nerve branches for selective cardiac VNS stimulation using micro-computed tomography (µCT) and 3D renderings.

Methods

Vagus nerve specimens (n= 11 pig nerves, n= 5 rabbit nerves) were harvested from the nodose ganglion down to the cardiac branches in domestic pigs and New Zealand White rabbits on both sides, and the cardiac autonomic innervation was mapped µCT and 3D renderings.

Results

Our results provide anatomical and topographical key features on the cervical and cardiac autonomic innervation including course of the cardiac branch, cardiac branching patterns, fascicle number, and size of the autonomic nerves. We also compared these aforementioned anatomical parameters between pigs and rabbits and highlighted key anatomical differences among individuals within pigs. In pigs, the cardiac branches were partly composed of both nerves even when they branched off the VN whereas in rabbits, the two nerves were completely separated and the cardiac branch was solely parasympathetic. Finally, we generated a 3D model of various parts of the VN specimen and compared them to images of the native nerves taken during VN dissection surgery.

Conclusions

Here we present an imaging approach to map the anatomy and topography of the cardiac Vagus Nerve for selective stimulation of cardiac VN branches. We also characterized the morphology of the VN, the sympathetic trunk (ST), and the cardiac branch (CB) at the level of the cardiac branching point to highlight the complex interplay between the nerves. Our data provide one possible reason for unwanted side effects of cervical VNS. However, future studies are required to broaden the knowledge in this specific research field of selective cardiac VNS.

Dapagliflozin alleviates left ventricular hypertrophy and cardiac dysfunction in mice

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): Ludwig Boltzmann Institute for Cardiovascular Research

Introduction

Sodium glucose cotransporter 2 inhibitors (SGLT2i) are a class of oral antidiabetic drugs. Recent clinical trials demonstrated and proved the cardiovascular benefit of SGLT2i in patients suffering from ischemic heart disease. In addition, left ventricular hypertrophy (LVH) is associated with cardiovascular events and using SGLT2i alleviated LVH in diabetic patients. However, only few studies investigated the effect of SGLT2i on regression of LVH in absence of diabetes.

Aim of the study

This study aimed to investigate whether the SGLT2i Dapagliflozin (DAPA) could attenuate LVH and cardiac dysfunction in a mouse model of pressure overload-induced LVH.

Methods

Male C57BL/6J mice (body weight 20-25g) were used. LVH was induced surgically by transverse aortic constriction (TAC). DAPA (1 mg/kg bodyweight/day) was administered through drinking water. The animals were divided in four groups: Group 1 underwent TAC for eight weeks (n=8). Group 2 concomitantly received DAPA for eight weeks after TAC (n=5). Group 3 received DAPA for only two weeks (in week 7 and 8 after TAC, n=5) to clarify if DAPA treatment could alleviate LVH at a later timepoint. Group 4 served as a sham control group (no LVH, n=8). Cardiac function was assessed using transthoracic echocardiography and invasive LV hemodynamic measurements.

Results

TAC resulted in a significant reduction in LV ejection fraction (LVEF) and significant increase in heart weight to body weight ratio (HW/BW) compared to sham (p&lt;0.001). In addition, TAC mice showed a significant increase of LV systolic pressure and end-diastolic pressure compared to sham (p&lt;0.01). Both the LVEF and LV functional parameters were markedly improved in mice treated with DAPA for eight weeks (p&lt;0.05). LV mass decreased compared to the untreated group. More importantly, DAPA treatment for only two weeks also improved LVEF and alleviated LVH compared to untreated TAC mice (p&lt;0.05). Furthermore, we also found that mice with only two weeks of DAPA treatment showed a tendency to improve LV hemodynamics.

Conclusions

DAPA was cardioprotective in a mouse model of pressure overload-induced LVH in absence of diabetes. It improved LV contractile function and LVH. DAPA also alleviated LVH and induced LV regression. Our findings uncovered that the SGLT2i DAPA contributed to the regression of LVH and cardiac fibrosis. Thus, administration of SLGT2i may be a novel adjunct therapy to boost reverse remodeling e.g. in patients with elective cardiac surgery and hypertrophic cardiomyopathy.

Dissecting the progression of cardiac dysfunction in tumor-bearing mice

Funding Acknowledgements

Type of funding sources: None.

Background

Cancer patients undergoing heart-related complications result in high incidences of mortality. Nevertheless, it is still not fully understood whether localized tumors affect heart function prior to the onset of cachexia, hence, making the heart more vulnerable for functional abnormalities in later stages of the disease. In addition to analyse heart function, we focus on the expression BCL-2–associated athanogene 3 (BAG3), a co-chaperone protein and Hsp70, which are highly expressed in tumor but decrease in cardiomyocytes (CM) in heart failure (HF).

Methods

Colon-26 adenocarcinoma cells (C26; n=22) with/without shIL-6 (C26 shIL-6; n=22) were injected subcutaneously into the right flank of 10-11 weeks old BALB/c male mice. Control mice were injected with vehicle (PBS; n=8). Cardiac function was assessed by echocardiography and invasive hemodynamic measurements 10 (early) and 20 (late) days after the injection, respectively. In addition, the expression of BAG3 and Hsp70 were determined by Western blot as well as the extend of cardiac fibrosis was determined by Masson-Goldner's trichrome staining.

Results

The tumor size was comparable between the two injected groups. However, only C26 group showed a significant loss of subcutaneous fat and skeletal muscle (p&lt;0.05, respectively), suggesting cachexia. Heart weight normalized to tibia length was not changed in the injected groups as compared to controls (day 20). However, left ventricular ejection fraction (LVEF) showed a tendency to decline in the early phase (p~0.08) in both injected group and it reached significance at late stage (p&lt;0.05). Invasive hemodynamic assessment also confirmed the contractile dysfunction, resulting in a decrease in LV systolic pressure and increase of LV end-diastolic pressure (p&lt;0.05, respectively). Importantly, these functional changes in the heart in tumor-bearing mice were associated with a marked reduction in both BAG3 and Hsp70 in the myocardium. Furthermore,  there was no sign of cardiac fibrosis in the injected groups.

Discussion

Our study shows for the first time that tumor rather than cancer cachexia plays a significant maladaptive role in the progression of cardiac dysfunction in a mouse model of C26 injection-induced cachexia. The progression of cardiac contractile dysfunction was associated with a decline in BAG3 and Hsp70 in tumor-bearing mice, suggesting changes of BAG3/Hsp 70 signalling may be a critical component as well as target.

Large and Small Animal Models of Heart Failure With Reduced Ejection Fraction

Heart failure (HF) describes a heterogenous complex spectrum of pathological conditions that results in structural and functional remodeling leading to subsequent impairment of cardiac function, including either systolic dysfunction, diastolic dysfunction, or both. Several factors chronically lead to HF, including cardiac volume and pressure overload that may result from hypertension, valvular lesions, acute, or chronic ischemic injuries. Major forms of HF include hypertrophic, dilated, and restrictive cardiomyopathy. The severity of cardiomyopathy can be impacted by other comorbidities such as diabetes or obesity and external stress factors. Age is another major contributor, and the number of patients with HF is rising worldwide in part due to an increase in the aged population. HF can occur with reduced ejection fraction (HF with reduced ejection fraction), that is, the overall cardiac function is compromised, and typically the left ventricular ejection fraction is lower than 40%. In some cases of HF, the ejection fraction is preserved (HF with preserved ejection fraction). Animal models play a critical role in facilitating the understanding of molecular mechanisms of how hearts fail. This review aims to summarize and describe the strengths, limitations, and outcomes of both small and large animal models of HF with reduced ejection fraction that are currently used in basic and translational research. The driving defect is a failure of the heart to adequately supply the tissues with blood due to impaired filling or pumping. An accurate model of HF with reduced ejection fraction would encompass the symptoms (fatigue, dyspnea, exercise intolerance, and edema) along with the pathology (collagen fibrosis, ventricular hypertrophy) and ultimately exhibit a decrease in cardiac output. Although countless experimental studies have been published, no model completely recapitulates the full human disease. Therefore, it is critical to evaluate the strength and weakness of each animal model to allow better selection of what animal models to use to address the scientific question proposed.

St Thomas Hospital polarizing cold cardioplegia does not have superior effects on hemodynamic parameters in an infarcted rat model

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Orphan Drugs

Background

The use of cardioplegic solutions is indispensable during cardiac arrest in order to reduce myocardial metabolism and oxygen demand. Most commonly, hypothermic hyperkalemic cardioplegic solutions are used for open heart surgery. However, high potassium concentrations have several effects that limit left ventricular recovery, such as intracellular calcium overload resulting in the loss of contractility and increased cell death. Recently, we have shown that polarized cardiac arrest results in similar myocardial protection and improves cardiac functional recovery in a porcine model of cardiopulmonary bypass.

Purpose

The purpose of this study was to identify and compare the hemodynamic effects of cold St Thomas’ Hospital polarizing cardioplegia (STH-Pol) in contrast to standard St Thomas’ Hospital cardioplegia (STH2) in rats with chronic myocardial infarction. We hypothesize that St Thomas’ Hospital polarizing cardioplegia shows superior protection on left ventricular hemodynamic recovery as compared to standard STH2 cardioplegia.

Methods

Permanent myocardial infarction was induced by permanent occlusion of the left anterior descending artery LAD on Sprague-Dawley rats (593 ± 65g, day of sacrifice). Six weeks post-MI, after echocardiography assessment, the animals were sacrificed, and hemodynamic parameters were measured in an erythrocyte-perfused isolated heart model (STH2, control group: n=5 or STH-Pol, study group: n=4). Fifteen minutes of Langendorff mode and 30 minutes of Working-heart mode were followed by cardiac arrest with the two types cardioplegia (was applied three times every 20 minutes (t1= 0, t2= 20, t3= 40)). STH-Pol, consisting of esmolol, adenosine and magnesium, was mixed with erythrocyte-buffer shortly prior to administration (1:4). After ischemia, the hearts were started with a hot shot with warm erythrocyte-buffer. Hemodynamic parameters were measured every five minutes in Langendorff mode and Working-heart mode. Finally, pump function was examined and tissue samples were taken for analysis of troponin-T and high-energy phosphates. Results will be given as % of preischemic baseline value.

Results

The use of STH-Pol instead of STH2 did not yield any significant differences in hemodynamic recovery (%) across the parameters of left atrial flow (LAF: 40.87 ± 13.22 vs. 53.24 ± 11.27), coronary flow (CF: 58 ± 14.36 vs. 76.21 ± 9) and cardiac output (CO: 42.82 ± 13.36 vs. 51.83 ± 11.76). Furthermore, we have not been able to identify superior effects of STH-Pol on stroke volume (SV: 46.55 ± 13.91 vs. 52.66 ± 11.33) recovery. Moreover, heart rate was comparable in both groups (92.07 ± 2.02 vs. 99.35 ± 1.72), which indicates swift reversal of negative chronotropic effects of esmolol.

Conclusion

Polarizing cardioplegic arrest does not show superior effects on hemodynamic parameters of left ventricular recovery after ischemia in chronically infarcted rat hearts as compared to depolarizing cardioplegic arrest.

Stromal Vascular Fraction-based patches generated under perfusion culture enhance cardiac function in rats with chronic myocardial infarction

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swiss National Foundation

The development of novel adjuvant angiogenic therapies to restore the low-perfused microvascular network upon myocardial infarction (MI) is crucial to avoid a possible end-stage heart failure. Of the current adult cell-based therapies, human adipose tissue-derived stromal vascular fraction cell (SVF) has vast reparative potential, principally due to: 1) its heterogeneous composition rich in mesenchymal stem cells (MSC), endothelial cells (EC), pericytes and hematopoietic cells, among others. In vitro engineering of SVF-based patches under unidirectional flow, applied by the help of a perfusion-based bioreactor, was found to increase certain cellular SVF subgroups such as pericytes, compared to static culture. In this study, we aimed at studying the potential of SVF-based engineered tissues in a model of chronic MI in nude rats. Human SVF cells were isolated upon liposuction and cultured on 3D collagen sponges (8 mm diameter, 3 mm thickness) either under constant unidirectional perfusion or in static condition for 5 days. Patches were characterized in terms of cellular composition prior to implantation. MI was induced by permanent ligation of the left anterior descending (LAD) coronary artery in male nude rats. Cardiac MRI was performed 4 weeks after MI; prior to the suture of patches and before sacrifice (4 weeks after implantation). Left ventricular ejection fraction (EF) was the surrogate marker and primary end point for cardiac pump function. Controls included untreated MI animals. Following perfusion culture, SVF cells were composed with a statistically superior percentage of pericytes, identified as CD45- CD34- CD146+ compared to static culture (28.06±10.03 and 3.37±2.50, respectively, p&lt;0.0007). The presence of other cell subpopulations was similar in the patches generated in perfusion or static culture. While the percentage of EF at the time of sacrifice resulted to be not statistically different between static and perfusion-based patches, statically generated constructs showed a general trend of decrease in the % EF before and after treatment (rat 1: 61.96 vs 52.90; rat 2: 55.39 vs 53.00; rat 3: 52.34 vs 50.62, respectively). Perfusion-cultured patches, instead, rather improved the cardiac function, measured as % EF (rat 1: 51.82 vs 58.72; rat 2: 51.66 vs 60.45; rat 3: 53.50 vs 52. 36, respectively for 4 weeks following MI and 4 weeks following treatment). When comparing the ratio of the % EF 8 weeks and 4 weeks between static or perfusion-based patches and the untreated controls, rats treated with patches generated under perfusion resulted to show higher levels of % EF, with an almost statistically difference (p=0.0556), compared to the control group. The observed results showed the great potential of human SVF-based patches in the improvement of the heart pump function.