Cardiac Markers Research Articles

Protective Role of Anthraquinone Purpurin Against Cardiotoxicity Induced by Isoproterenol in Adult Wistar Rats

Background Purpurin are naturally occurring anthraquinones derived from the roots of Rubia species. Purpurin is a red-colored bioactive compound commonly used as a food colorant. In ancient times, Rubia species plants were used in Chinese medicine to treat rheumatoid arthritis. Research studies have proven purpurin exerts antimicrobial, neuromodulatory, antigenotoxic, anti-inflammatory, anticancer, and antioxidant effects. The present investigation was proposed to evaluate the efficacy of purpurin against myocardial infarction in rats. Materials and Methods Purpurin was pretreated in healthy adult male rats and subjected to a myocardial infarction with isoproterenol to assess the cardioprotective effect of purpurin. CRP, total protein, and uric acid levels were quantified to analyze the efficacy against myocardial infarction. Cardiac functional markers and antioxidant levels were measured to evaluate the role of purpurin on isoproterenol-induced myocardial infarction. Further to prove the cardioprotective efficacy of purpurin cardiac tissue ATPases and electrolytes were assessed in the experimental animals. The anti-inflammatory property of purpurin was analyzed by quantifying proinflammatory cytokines. Histopathological analysis of cardiac tissue was to confirm the protective effect of purpurin against isoproterenol-induced myocardial infarction. Results The present investigation demonstrated the significant protective effect of purpurin by decreasing the levels of CRP, uric acid levels, and total protein levels in myocardial infarction-induced rats. It restored the cardiac functional markers and glutathione system in the cardiac tissue of myocardial infarction-induced rats. It increased the levels of cardiac ATPases and reinstated the electrolytes in the cardiac tissue of myocardial infarction-induced rats. Purpurin significantly demonstrated an anti-inflammatory and cardioprotective effect that was evidenced with histopathological analysis. Conclusion Our findings prove purpurin suppresses the proinflammatory response of isoproterenol treatment and exerts a cardioprotective effect in myocardial infarction-induced rats.

Cardioprotective effect of tofisopam against isoprenaline-induced myocardial infarction in rats via modulation of NLRP3\\IL-1β\\caspase-1 pathway

Purpose Cardiovascular diseases (CVDs) are a leading cause of morbidity and mortality worldwide. Ischemic heart diseases, particularly acute myocardial infarction (MI), represent the most common cause of death. MI is influenced by multiple factors, including the release of inflammatory mediators. A significant percentage of individuals with CVD experience psychological effects, such as anxiety and depression, which are linked to an increased risk of coronary heart disease. Certain anti-anxiety medications have demonstrated immunomodulatory and anti-inflammatory effects. Tofisopam, a 2,3-benzodiazepine with anxiolytic properties, has been shown to exert in vitro anti-inflammatory and immunomodulatory effects. The present study investigates the potential of tofisopam as a protective adjuvant against isoprenaline-induced MI in rats and explores the possible underlying mechanisms. Methods The study included four groups: a control group, a group pretreated with tofisopam, an isoprenaline toxic group, and an isoprenaline toxic group pretreated with tofisopam. Results The findings demonstrated that isoprenaline significantly increased cardiac enzyme levels, as well as elevated oxidative and inflammatory stress parameters, along with evident apoptosis in cardiac cells. In contrast, the tofisopam-pretreated group showed a significant reversal of the cardiac damage induced by isoprenaline. Conclusions Tofisopam protects against isoprenaline-induced MI through its antioxidant, anti-inflammatory, and anti-apoptotic properties.

Cardioprotective effects of liposomal resveratrol in diabetic rats: unveiling antioxidant and anti-inflammatory benefits

ABSTRACT As a consequence of chronic hyperglycemia, diabetes complications and tissue damage are exacerbated. There is evidence that natural phytochemicals, including resveratrol, a bioactive polyphenol, may be able to reduce oxidative stress and improve insulin sensitivity. However, resveratrol's limited bioavailability hampers its therapeutic effectiveness. By using liposomes, resveratrol may be better delivered into the body and be more bioavailable. The objective of this study was to assess the cardioprotective potential of liposome-encapsulated resveratrol (LR) in a streptozotocin-induced (STZ) diabetic rat model. Adult male Wistar rats were categorized into five groups: control, diabetic, resveratrol-treated (40 mg/kg), liposomal resveratrol (LR)-treated (20 mg/kg) and liposomal resveratrol (LR)-treated (40 mg/kg) for a five-week study period. We compared the effects of LR to those of resveratrol (40 mg/kg) on various parameters, including serum levels of cardiac markers, tissue levels of pro-inflammatory cytokines, nuclear transcription factor, oxidative stress markers, and apoptotic markers. LR treatment in STZ-diabetic rats resulted in notable physiological improvements, including blood glucose regulation, inflammation reduction, oxidative stress mitigation, and apoptosis inhibition. LR effectively lowered oxidative stress and enhanced cardiovascular function. It also demonstrated a remarkable ability to suppress NF-kB-mediated inflammation by inhibiting the pro-inflammatory cytokines TNF-α and IL-6. Additionally, LR restored the antioxidant enzymes, catalase and glutathione peroxidase, thereby effectively counteracting oxidative stress. Notably, LR modulated apoptotic regulators, including caspase, Bcl2, and Bax, suggesting a role in regulating programmed cell death. These biochemical alterations were consistent with improved structural integrity of cardiac tissue as revealed by histological examination. In comparison, resveratrol exhibited lower efficacy at an equivalent dosage. Liposomal resveratrol shows promise in alleviating hyperglycemia-induced cardiac damage in diabetes. Further research is warranted to explore its potential as a therapeutic agent for diabetic cardiovascular complications and possible cardioprotective effects.

Post operative outcomes of del-nido cardioplegia in adult cardiac surgery.

Objective: To evaluate the post-operative results for defibrillator use, length of hospital stay, and ionotropic support in adult patients who underwent cardiac surgery in Del-Nido Cardioplegia. Cardiac enzymes and potassium levels are measured before and after surgery in adult cardiac surgery patients in order to look for arrhythmias. Study Design: Observational Cross-sectional study. Setting: Afridi Medical Complex, Peshawar. Period: October 2022 to March 2023. Methods: 50 Patients were selected randomly by using Non-Probability Convenient sampling method technique. Results: In our study the mean age of patients was (50.92 ±9.429). Cardiac enzyme level post-op after 24 hours (67.3540±23.21292). Potassium level post-op group (4.5590± .65033), and length of hospital stay (8.58±1.486). Post operative outcomes shows significant association p value <0.05. Conclusion: This study concluded that Del Nido Cardioplegia is an intented and brief arrest of heart function, especially in cardiopulmonary Bypass surgery. Better myocardial protection is provided by Del-Nido Cardioplegia and it is very safe and effective process. It Provide good post operative outcome as are available in different literature reviews preceding our study.

Sevoflurane Affects Myocardial Autophagy Levels After Myocardial Ischemia Reperfusion Injury via the microRNA-542-3p/ADAM9 Axis.

This research focused on investigating the effects of sevoflurane (Sev) on myocardial autophagy levels after myocardial ischemia reperfusion (I/R) injury via the microRNA-542-3p (miR-542-3p)/ADAM9 axis. Mice underwent 30min occlusion of the left anterior descending coronary (LAD) followed by 2h reperfusion. Cardiac infarction was determined by 2,3,5-triphenyltetrazolium chloride triazole (TTC) staining. Cardiac function was examined by echocardiography. Cardiac markers and oxidative stress factors were evaluated by ELISA. Autophagy-associated factors were detected by western blot. Relationship between miR-542-3p and ADAM9 was tested by dual-luciferase reporter gene assay, RT-qPCR, and western blot. Sev treatment ameliorated cardiac dysfunction, myocardial oxidative stress, and histopathological damages, decreased myocardial infarction size and myocardial apoptotic cells after myocardial I/R injury. Sev treatment elevated miR-542-3p expression and decreased ADAM9 expression in myocardial tissues after myocardial I/R injury. miR-542-3p overexpression could enhance the ameliorative effects of Sev on myocardial injury and myocardial autophagy in I/R mice. miR-542-3p targeted and negatively regulated ADAM9 expression. ADAM9 overexpression reversed the ameliorative effects of miR-542-3p up-regulation on myocardial injury and myocardial autophagy in Sev-treated I/R mice. Sev treatment could ameliorate myocardial injury and myocardial autophagy in I/R mice, mediated by mechanisms that include miR-542-3p up-regulation and ADAM9 down-regulation.

Liraglutide Improves Diabetic Cardiomyopathy by Downregulation of Cardiac Inflammatory and Apoptosis Markers.

Diabetic cardiomyopathy is one of the leading causes of mortality for people with diabetes worldwide. The majority of the formalistic alterations in the heart associated with diabetic cardiomyopathy have been found to be primarily caused by the ongoing oxidative stress brought on by hyperglycemia, which leads to the dysfunctional reactions of apoptosis and inflammation. Liraglutide, a long-acting counterpart of glucagon-like peptide-1, has been demonstrated to have a number of therapeutic applications in medicine and other biological processes. The PubMed database was searched using the terms liraglutide, DCM, and all associated inflammatory markers. There has been a lot of research on liraglutide's potential to protect the heart from cardiomyopathy brought on by diabetes. Liraglutide's therapeutic actions as an antioxidant, antihyperglycemic, anti-apoptotic, and anti-inflammatory medicine may help to lessen diabetic cardiomyopathy. The most recent studies on the effects of liraglutide therapy on DCM are presented in this review, along with an explanation of the underlying mechanisms.

A review of alternative measurements in strain imaging for ventricular arrhythmia prediction

Global longitudinal strain has been established as a reliable tool to assess global left ventricular function and a marker of subclinical left ventricular dysfunction unrecognized by the ejection fraction. On the other hand, ventricular arrhythmias are the most common cause of sudden cardiac death. Their early detection is a challenge. Possible prognostic markers for the risk of ventricular arrhythmias are discussed in the literature – electrocardiographic, cardiac magnetic resonance, computed tomography, radionuclide imaging, and markers from new echocardiographic techniques. Of the latter, at this stage of knowledge, several markers have been discussed as informative for predicting ventricular arrhythmias – global longitudinal strain, radial strain and mechanical dispersion, and most recently, myocardial work. As far as we are informed, global longitudinal strain is particularly useful in patients with normal echocardiographic parameters such as left ventricular ejection fraction, left atrial diameter, left ventricular wall thickness, and aortic root. The relationship between mechanical dispersion and ventricular arrhythmias has been widely studied. The relationship has been studied more in some patient populations – heart failure, ischemic heart disease, long QT syndrome and arrhythmogenic cardiomyopathy, congenital heart disease. The role of mechanical dispersion as a predictor of ventricular arrhythmias in metabolic syndrome is scarce.

Low-dose dobutamine in acute myocardial infarction with intermediate to high risk of cardiogenic shock development (the DOBERMANN-D trial): study protocol for a double-blinded, placebo-controlled, single-center, randomized clinical trial

BackgroundCardiogenic shock (CS) occurs in 5–10% of patients with acute myocardial infarction (AMI), and the condition is associated with a 30-day mortality rate of up to 50%. Most of the AMI patients are in SCAI SHOCK stage B upon hospital arrival, but some of these patients will progression through the stages to overt shock (SCAI C-E). Around one third of patients who develop CS are not in shock at the time of hospital admission. Pro-B-type natriuretic peptide (proband) is a biomarker closely related to CS development. The aim of this study is to investigate the potential for preventing progression of hemodynamic instability by early inotropic support with low-dose dobutamine infusion administrated after revascularization in AMI patients with intermediate to high risk of in-hospital CS development.MethodsThis investigator-initiated, double-blinded, placebo-controlled, randomized, single-center, clinical trial will include 100 AMI patients (≥ 18 years) without CS at hospital admission and at intermediate-high risk of in-hospital CS development (ORBI risk score ≥ 10). Patients will be randomized in a 1:1 ratio to a 24 h intravenous (IV) infusion of dobutamine (5 μg/kg/min) or placebo (NaCl) administrated after acute percutaneous coronary intervention (PCI) (< 24 h from symptom onset). Blood samples are drawn at time points from study inclusion (before infusion, 12, 24, 36, and 48 h).The primary outcome is peak plasma proBNP within 48 h after infusion as a surrogate-measure for the hemodynamic status. Hemodynamic function will be assessed pulse rate, blood pressure, and lactate within 48 h after infusion and by transthoracic echocardiography (TTE) performed after 24–48 h and at follow-up after 3 months. Markers of cardiac injury (troponin T and creatine kinase MB (CK-MB)) will be assessed.DiscussionEarly inotropic support with low-dose dobutamine infusion in patients with AMI, treated with acute PCI, and at intermediate-high risk of in-hospital CS may serve as an intervention promoting hemodynamic stability and facilitating patient recovery. The effect will be assessed using proBNP as a surrogate marker of CS development, hemodynamic measurements, and TTE within the initial 48 h and repeated at a 3-month follow-up.Trial registrationThe Regional Ethics Committee: H-21045751. EudraCT: 2021–002028-19. ClinicalTrials.gov: NCT05350592, Registration date: 2022-03-08. WHO Universal Trial Number: U1111-1277–8523.

A novel 3D cardiac microtissue model for investigation of cardiovascular complications in rheumatoid arthritis

BackgroundRheumatoid arthritis (RA) is a chronic inflammatory disease that affects not only the joints but also has significant cardiovascular (CV) manifestations. The mechanistic interplay between RA and cardiovascular complications is not yet well understood due to the lack of relevant in vitro models. In this study, we established RA cardiac microtisses (cMTs) from iPSC-derived cardiomyocytes (CMs), endothelial cells (ECs) and cardiac fibroblasts (CFs) to investigate whether this fully human 3D multicellular system could serve as a platform to elucidate the connection between RA and CV disorders.MethodsPBMC and FLS from healthy and RA donors were reprogrammed to hiPSCs with Sendai vectors. hiPSCs pluripotency was assessed by IF, FACS, spontaneous embryoid bodies formation and teratoma assay. hiPSCs were differentiated to cardiac derivatives such as CMs, ECs and CFs, followed by cell markers characterizations (IF, FACS, qRT-PCR) and functional assessments. 3D cMTs were generated by aggregation of 70% CMs, 15% ECs and 15% CFs. After 21 days in culture, structural and metabolic properties of 3D cMTs were examined by IF, qRT-PCR and Seahorse bioanalyzer.ResultshiPSCs demonstrated typical colony-like morphology, normal karyotype, presence of pluripotency markers, and ability to differentiate into cells originating from all three germ layers. hiPSC-CMs showed spontaneous beating and expression of cardiac markers (cTnT, MYL7, NKX2.5, MYH7). hiPSC-ECs formed sprouting spheres and tubes and expressed CD31 and CD144. hiPSC-CFs presented spindle-shaped morphology and expression of vimentin, collagen 1 and DDR2. Self-aggregation of CMs/ECs/CFs allowed development of contracting 3D cMTs, demonstrating spherical organization of the cells, which partially resembled the cardiac muscle, both in structure and function. IF analysis confirmed the expression of cTnT, CD31, CD144 and DDR2 in generated 3D cMTs. RA cMTs exhibited significantly greater formation of capillary-like structures, mimicking enhanced vascularization—key RA feature—compared to control cMTs. Seahorse examination of cMTs revealed changes in mitochondrial and glycolytic rates in the presence of metabolic substrates and inhibitors.ConclusionsThe cMTs model may represent an advanced human stem cell-based platform for modeling CV complications in RA. The highly developed capillary-like structures observed within RA cMTs highlight a critical feature of inflammation-induced CV dysfunction in chronic inflammatory diseases.

Patterned glycopeptide-based supramolecular hydrogel promotes the alignment and contractility of iPSC-derived cardiomyocytes

The functional restoration of a damaged cardiac tissue relies on a synchronized contractile capacity of exogenous and/or endogenous cardiomyocytes, which is challenging to achieve. Here, we explored the potential of the short glycopeptide diphenylalanine glucosamine-6-sulfate (FFGlcN6S) conjugated with an aromatic moiety, namely fluorenylmethoxycarbonyl (Fmoc), to enhance cardiac tissue regeneration. At physiological conditions, Fmoc-FFGlcN6S assembles into nanofibrous hydrated meshes, i.e., matrix mimicking hydrogels. These hydrogels can be further micropatterned allowing co-existence of hierarchical structures at different lenght. The patterned hydrogels support the culture of induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) and promote their alignment. The cultured iPSC-CMs exhibit anisotropic synchronized contractions, indicating maturation and electrical interconnectivity. Moreover, the cultures express specific cardiac markers including, connexin-43 and sarcomeric-α-actinin, confirming enhanced cell-cell crosstalk, spontaneous contractility, and efficient transmission of electrical signals. Our results showcase the potential of short amphiphilic glycopeptides to mimic physical and biochemical cues that are essential for cardiomyocytes functionality and thus, these conjugates can be used in cardiac tissue engineering and regeneration.

Impact of a prehospital mobile cloud ECG transmission system on door-to-balloon time, myocardial damage and mid-term all-cause mortality in patients with ST-elevation myocardial infarction

Abstract Background Guidelines recommend to establish a regional reperfusion strategy to maximize the efficiency of care for patients diagnosed with ST-elevation myocardial infarction (STEMI). In Addition, the recently developed mobile cloud-based 12-lead electrocardiogram (ECG) transmission system enables the transmission of prehospital ECGs at a low cost. Medical staff can use electronic devices to access and review ECGs from anywhere. However, the effectiveness of the prehospital mobile cloud ECG system has not yet been clearly established. Objective This single-center study aims to evaluate the impact of the prehospital mobile cloud ECG system on reducing Door-to-Balloon Time (DTBT), myocardial damage, and mid-term all-cause mortality in patients with STEMI. Methods In June 2018, eight prehospital Mobile Cloud ECG Transmission systems were integrated into the regional Emergency Medical Service (EMS) in our region. This study examined and compared Door-to-Catheterization Laboratory Time (DTCT), DTBT, Onset-to-Reperfusion Time (OTRT), peak creatine kinase-MB (CK-MB) levels, and one-year mortality rates of STEMI patients in the five years before and after introducing the prehospital mobile cloud ECG system. From June 2013 to May 2023, our institute received a total of 426 STEMI patients via ambulances from these two EMS departments. After excluding 23 patients with OTRT exceeding 24 hours and 76 patients who were transferred without the system post-introduction, 327 consecutive STEMI patients who underwent emergency percutaneous coronary intervention (PCI) were included in the study. The patients were divided into two groups: 169 patients before the prehospital mobile cloud ECG system introduction and 158 patients after that. Results There were no significant differences in age, gender, past medical history, and Killip Class IV between the two groups, except for the proportion of left main trunk (LMT) lesions, which was significantly higher in the ECG group. Significant reductions were observed in both DTCT and DTBT in the group after introduction, with differences noted as (DTCT: 42 min vs. 26 min; p &amp;lt; 0. 001, and DTBT: 74 min vs. 56 min; p &amp;lt; 0.001, respectively). However, the OTRT did not show a significant difference. Peak creatine kinase-MB (CK-MB) levels did not differ between the two groups, and Kaplan-Meier analysis revealed no significant difference in one-year mortality between them. Multivariate Cox regression analysis, which included variables such as age, peak CK-MB levels, Killip Class IV, LMT lesions, OTRT and the prehospital mobile cloud ECG transmission system usage, revealed that only Killip Class IV was significantly associated with one-year mortality (hazard ratio of 2.82 and a 95% confidence interval of 1.61-4.94; p=0.0003). Conclusion The prehospital mobile cloud ECG transmission system significantly reduced DTBT, but did not lead to a reduction in myocardial damage or an improvement in mid-term prognosis.Effect of the ECG Transmission SystemKaplan-Meier analysis

Heparin reversal for coronary artery perforation

Abstract Background/Introduction In the management of coronary artery perforation (CAP) during percutaneous coronary intervention (PCI), heparin reversal can provide hemostatic effects but raises concerns about potential coronary thrombosis if an intracoronary artery guidewire or balloon is in place. Purpose We aimed to evaluate the safety and efficacy of heparin reversal during device insertion for CAP. We also aimed to determine the optimal target activated clotting time (ACT) to maintain when performing heparin reversal. Methods We analyzed cases of CAP which occurred during PCI procedures in a single center from January 2006 to October 2023. Patients were assigned to two groups according to whether they received heparin reversal with a device in place. The safety outcome was the periprocedural myocardial infarction (creatine kinase-MB &amp;gt;5 times the upper normal limit), and the efficacy outcome was successful hemostasis at the end of the procedures (complete absence of CAP on angiography). Results Among the 22,368 cases, 368 (1.6%) developed CAP, consisting of main vessels 45%, distal vessels 43%, and collateral vessels 12%. Heparin reversal with a device in place was implemented in 211 (57%) cases. Of these, 16 (7.6%) experienced coronary thrombosis. After adjusting covariates by the multivariable logistic regression model, heparin reversal with a device in place was significantly associated with a higher incidence of periprocedural myocardial infarction (11% vs 4.5%; adjusted OR: 3.11; 95% CI: 1.24–7.78; P = 0.015) and a higher rate of successful hemostasis (91% vs 73%; adjusted OR: 2.78; 95% CI: 1.27–6.09; P = 0.011). In the analysis of cases where minimum ACT value was available (n = 251), this value was significantly correlated with coronary thrombosis (r = −0.16, P = 0.012). When the cutoff values of minimum ACT were set at 200, 150, and 120 seconds as a binomial variable, the correlation coefficient was r = −0.08 (P = 0.158), r = −0.16 (P = 0.009), r = −0.20 (P = 0.001), respectively. Conclusions Heparin reversal after CAP with an intracoronary artery device in place was significantly associated with a higher incidence of periprocedural MI but also a higher rate of successful hemostasis. A minimum ACT value &amp;lt;150 seconds was significantly correlated with coronary thrombosis. These results propose a novel algorithm for CAP management strategies.Management algorithm for CAP

The coronary angiography-derived index of microcirculatory resistance predicts perioperative myocardial injury in stable coronary artery disease patients undergoing PCI

Abstract Background Coronary microvascular dysfunction (CMD) assessed by the index of microcirculatory resistance (IMR) is associated with perioperative myocardial injury(PMI).The angiography-derived index of microcirculatory resistance (caIMR) is a novel and accurate alternative of IMR. Objective This study aims to evaluate the predictive value of caIMR on PMI in stable coronary artery disease (CAD) patients undergoing percutaneous coronary intervention (PCI). Methods Consecutive stable CAD patients undergoing elective PCI of a single lesion were recruited. caIMR were measured before and after revascularization.Total creatine kinase-MB (CK-MB) and high sensitivity Troponin T (hsTnT) levels were measured before and within 24 hours after PCI. Results A total of 65 patients were enrolled, twenty-six patients fulfilled the diagnostic criteria of PMI. Post-PCI caIMR values in the PMI group were significantly higher than those in the control group (27.02±3.70 vs. 15.91±3.43U, P&amp;lt;0.001). Pearson correlation analysis demonstrated that increased post-PCI caIMR values have a significant positive correlation with peak hsTnT (r = 0.803, P&amp;lt;0.001) and peak CK-MB (r = 0.512, P= 0.001). Multivariate logistic regression analysis showed the post-PCI caIMR was independent predictors of PMI(OR,1.731;95% CI:1.348-2.023; P&amp;lt;0.001).The ROC analysis suggested that the best cutoff value of post-PCI caIMR was 25.17U to diagnose PMI(AUC=0.951, sensitivity 88.5%, specificity 97.1%%). Conclusions The post-PCI caIMR can accurately predict PMI in stable CAD patients receiving elective PCI, supporting its use in clinical practice.

Engineering hiPSC-derived tissue models for advanced amyloidosis research and therapy development

Abstract Introduction Transthyretin (TTR) amyloid cardiomyopathy (ATTR-CM) is a life-threatening disease currently lacking an optimal therapy, stemming from the absence of representative models. Our work aims to stablish for the first time an all-human 3D model of ATTR-CM where the main cellular and extracellular players of the pathology are present. Methodology A human induced pluripotent stem cell (hiPSC) line was derived from a patient carrying a p.Ser43Asn TTR mutation and differentiated into hepatocytes (hiPSC-HEPs), cardiomyocytes (hiPSC-CMs) and cardiac fibroblasts (hiPSC-CFs). Cells were embedded in a hydrogel (tailored for each cell type) and combined with a designed 3D printed scaffold using Melt Electro Writing (MEW) technology. Tissues were maintained in culture for up to 4 weeks and characterized by staining, albumin production, electrophysiological, plus genomic analysis. Exposure to TTR fibrils (TTR-FIB) was evaluated. Results Human hepatic and cardiac functional tissues can be generated using MEW-designs. These constructs exhibited albumin production and an active spontaneous contraction, respectively. Moreover, tissues displayed well distributed cells throughout the 3D-structure, positive for specific hepatic and cardiac mature markers. Interestingly, electrophysiological analysis showed that cardiac tissues displayed shortened calcium transients after TTR-FIB exposure compared to unexposed tissues. However, no differences were found in terms of beat rate, metabolic activity and gene expression for the concentrations used. Conclusion We have developed an advanced model of ATTR-CM capable of recapitulating the multisystem complexity of the disease, which will contribute to advancing our understanding of the mechanisms of the disease, and help discovering and formulating new treatments.

The essential role of the miRNA-208a/TARBP2/Sox6 axis in myosin expression in the end stage human heart failure

Abstract Despite diverse aetiologies, failing human hearts (HF) of various origins (coronary artery disease (CAD), dilated cardiomyopathy (DCM), restrictive cardiomyopathy, and hypertrophic cardiomyopathy (HCM)) exhibit impaired contractility and share alterations in MYH6, MYH7, and MYH7B gene expression. Here, we explore the miRNA-208a/TARBP2/Sox6 axis in regulating myosin expression within left ventricles of explanted human hearts. Methods Samples of left ventricles were obtained from explanted hearts of patients with terminal HF (NYHA III-IV) and reduced left ventricle ejection fraction (LVEF &amp;lt;25%) due to CAD (n=10), DCM (n=10), HCM (n=6), and controls (n=5). We analysed the expression of cardiac myosin heavy chains (MYH6, MYH7, MYH7B), cardiac damage markers (ANP, BNP), and heart-related MyoMiRs using quantitative real-time PCR. Results Pre-transplant data for the 31 subjects (25 male, 3 female) included: age 54.4±8.2y, BP 112±18/67±11 mmHg, HR 79±16 min-1, LVEF 27±14%, LVEDD 8.8±15.8mm, RVEDD 32.8±5.1mm, QRS 0.140±0.05s, QT 0.42±0.04s, NT-proBNP 5551±4259 ng/l. In all diseased groups, MYH6 mRNA was downregulated, while MYH7 and MHRT ncRNA were upregulated. We observed strong positive correlations between MYH7, MYH7B, and MHRT transcription, suggesting coordinated expression. The miRNA-208a/miRNA-208b ratio shifted heavily towards miRNA-208b in controls, with a similar effect for miRNA-499 and MYH7B. A strong negative correlation existed between miRNA-499 and MYH7B expression across HF samples. TARBP2 expression decreased slightly in all pathological groups, while Sox6 mRNA increased. Conclusion Elevated Sox6 expression may contribute to MYH6 downregulation and MYH7/MYH7B upregulation. Altered TARBP2 expression could promote cardiomyopathy via Sox6-mediated repression of cardiac slow-twitch myofiber proteins. Changes in miRNA-208a processing leading to Sox6 upregulation may inhibit Sox6-dependent myosin transcript expression.

Changes in blood metabolomes as potential biomarkers for severity and prognosis in doxorubicin-induced heart failure: a study in HER2-positive and HER2-negative breast cancer patients

Abstract Background The use of doxorubicin for breast cancer treatment is often limited due to cardiotoxicity. Doxorubicin was shown to cause the alterations of cardiac metabolome levels in doxorubicin-treated rats. Interestingly, these changes were robustly associated with the development of doxorubicin-induced heart failure. Unfortunately, measurements of cardiac metabolome levels are rarely possible in humans. Hence, non-invasive biomarkers as representatives of doxorubicin-induced heart failure are required in clinical research and practice. Human epidermal growth factor receptor 2 (HER2) is a point of interest in breast cancer treatment. HER2 is associated with tumor aggressiveness. However, it was observed that HER2 protected against systemic oxidative stress and dilated cardiomyopathy. Therefore, we hypothesized that the alterations of blood metabolome levels and cardiac functions following doxorubicin treatment were different between HER2-positive and HER2-negative breast cancer patients. Purpose We determined the potential roles of changes in blood metabolomes as severity and prognostic markers of doxorubicin-induced heart failure. In addition, the changes in blood metabolomes and cardiac parameters following doxorubicin treatment in HER2-positive and HER2-negative breast cancer patients were compared. Methods HER2-positive (n=37) and HER2-negative (n=37) breast cancer patients were enrolled. Echocardiography, heart rate variability, and blood collection were performed at baseline and 2 weeks after completion of doxorubicin treatment in all patients, as well as at 3 months after completion of doxorubicin treatment in HER2-negative breast cancer patients. Blood obtained at all 3 time points was processed for measuring cardiac injury markers. Blood obtained at baseline and 2 weeks after completion of doxorubicin treatment was also processed for measuring oxidative stress in peripheral blood mononuclear cells using flow cytometry and 85 metabolome levels in plasma using mass spectrometry-based targeted metabolomics. Results Cardiac injury and systolic dysfunction at 2 weeks after completion of doxorubicin treatment were comparable between HER2-positive and HER2-negative breast cancer patients. However, only HER2-negative breast cancer patients exhibited increased systemic oxidative stress and cardiac autonomic dysfunction at this time point. Moreover, 33 and 29 blood metabolomes were altered at 2 weeks after completion of doxorubicin treatment in HER2-positive and HER2-negative breast cancer patients, respectively (Figure). Interestingly, the changes in most of these metabolomes were correlated with the changes in cardiac parameters, both at 2 weeks and 3 months after completion of doxorubicin treatment (Figure). Conclusions The changes in blood metabolomes following doxorubicin treatment were dependent on HER2 status, which might be served as severity and prognostic markers of doxorubicin-induced heart failure.

SMAD3 silencing induces Epithelial-to-Mesenchymal Transition (EMT) towards cardiac pericyte progenitors with proangiogenic potential in hiPSC-derived epicardial cells

Abstract Background The epicardium is only a single mesothelial layer and "quiescent" in the adult heart. However, once the heart is injured, the epicardium reactivates and acts as a key for cardiac regeneration through epithelium-to-mesenchymal transition (EMT). While the canonical TGF-β-SMAD pathway plays a central role in regulating EMT, SMAD3 functions independent of this pathway in epicardium remain unknown. Purpose The purpose of this study is to investigate the effects of SMAD3 downregulation on EMT in epicardial cells. Methods First, we differentiated human iPSC-derived epicardial cells (EPI cells) by mimicking the process of cardiac mesoderm development. Next, siRNA targeting SMAD3 was transfected into EPI cells to silence SMAD3. We performed qRT-PCR, western blotting, immunocytochemistry, flow cytometry, transcriptional analysis, endothelial tube formation assay, and paracrine experiments using FUCCI (fluorescent ubiquitination-based cell cycle indicator) system to evaluate the phenotype of EPI cells with silenced SMAD3. Results We found that SMAD3 silencing in EPI cells resulted in loss of epicardial identity and upregulation of multiple EMT markers. Additionally, NG2 and ENG (CD105), both cardiac pericyte markers, were highly expressed in SMAD3-silenced EPI cells. RNA-sequence also revealed that SMAD3 silencing in EPI cells induced EMT facilitated towards cardiac pericyte progenitors with proangiogenic potential. In endothelial tube formation assay, SMAD3-silenced EPI cells demonstrated enhanced tube formation compared to the control (1.48-fold increase in the number of junctions, n=3; p&amp;lt;0.0001), which indicated their angiogenic potential. At last, we revealed the paracrine effect of SMAD3-silenced EPI cells to enhance the proliferative reactivation in iPSC-derived cardiomyocytes by showing upregulation in CDK6/CCND1 axis and FUCCI-green. Conclusion Our findings demonstrate a new role of SMAD3 biology in the human epicardium, specifically in the generation of cardiac pericyte progenitor cells that contribute to better responses in angiogenesis of the heart microvasculature enabling the possibility to continue exploiting epicardial biology for effective cardiac regeneration.

The condition of myocardium reserves score from a cloud-based analytics platform of Holter ECG data indicates better cardiometabolic function in heart failure

Abstract Introduction Cardiometabolic dysregulation, particularly type 2 diabetes mellitus (T2DM), is associated with subtle myocardial pathologies, even in individuals without known cardiovascular disease. These subclinical changes, often undetectable by standard electrocardiogram (ECG) analytics, can offer valuable insights into the relationship between metabolic health and cardiac function. Novel ECG markers, developed through machine learning and artificial intelligence (AI), may provide the sensitivity needed to detect such changes. Aim This study aims to evaluate novel composite cardiac parameters from an analytics platform in the context of heart failure (HF), seeking to understand their relationship to cardiometabolic dysregulation. Methods Data from the MyoVasc study, a prospective cohort on HF, were analysed. Participants underwent extensive clinical phenotyping, including a Holter ECG assessment. Holter ECG data was processed based on machine learning and AI models on a cloud-based analytics platform (Cardiolyse, Helsinki, Finland), generating both traditional and proprietary ECG, and heart rate variability cardiac health markers. LASSO-penalized logistic regression adjusted for sex and age was performed to select the marker most strongly associated with T2DM. The identified marker was then evaluated in relation to cardiac function and structure as well as HF-related outcome. Results A total of 953 subjects (mean±SD age 64.6±10.5 years; 35.7% women) were included in the analyses. Symptomatic HF stage C/D was present in 54.8% (n=522) of subjects and diabetes mellitus in 22.4% (n=213). The Condition of Myocardium Reserves Score (CMRS) was the novel composite cardiac parameter selected based on its relationship with T2DM. In a Poisson regression model with robust variance adjusted for sex and age, a lower score was associated with T2DM (Prevalence ratio per SD 1.24, 95% confidence interval [1.14;1.36], P=0.0002). In multivariable linear regressions adjusted for traditional cardiovascular risk factors, comorbidities, and medication, a higher CMRS was associated with better global longitudinal strain (β per SD –0.82 [–1.11;–0.53], P&amp;lt;0.0001), diastolic function (left ventricular E/e’; β per SD –0.04 [–0.06;–0.01], P=0.0059) and systolic function (LV ejection fraction; β per SD 2.06 [1.46;2.67], P&amp;lt;0.0001). A lower CMRS independently predicted all-cause death (Hazard ratio per SD 1.25 [1.09;1.45], P=0.0020) and worsening of HF (HR per SD 1.44 [1.21;1.72], P&amp;lt;0.0001) in Cox regression analysis adjusted for the same confounders. Conclusion The Condition of Myocardium Reserves Score exhibited a strong association with cardiometabolic dysregulation. A higher CMRS indicated preserved cardiac function, while a lower score independently predicted increased risk of all-cause death and worsening HF. This novel score offers potential as a non-invasive tool for assessing cardiometabolic health and stratifying risk in patients with HF.

Effects of empagliflozin on cardio-renal interaction in heart failure with reduced ejection fraction: results from in-vivo experiments and the CINNAMON-study

Abstract Background Heart failure is often accompanied by renal dysfunction, which indicates a pathophysiological connection between the heart and kidneys. Empagliflozin, a SGLT2 inhibitor, showed beneficial effects on both cardiovascular and renal endpoints. Mechanistically, however, it is unclear whether the empagliflozin-dependent renal protection is mediated via the inhibition of renal SGLT2 or rather indirectly via improved cardiac function. Interestingly, in the EMPEROR trials, there was a significant interaction of empagliflozin-dependent kidney protection with systolic contractile dysfunction. We hypothesized that Empagliflozin treatment ameliorates heart failure in response to chronic pressure overload in mice leading to improved renal function. We correlated these findings with data from our prospective, single-armed trial. Methods Transverse aortic constriction (TAC) or sham surgery was performed in C57BL/6J (wildtype, WT) and SGLT2 deficient mice (SGLT2-/-). Animals received either Empagliflozin (10 mg/kg bodyweight) or vehicle by daily oral gavage. Cardiac function was evaluated by echocardiography and kidney function by transdermal FITC-Sinistrin measurement (GFR), urinary albumin/creatinine ratio (UACR) and Siriusred fibrosis staining. Results After 10 weeks, echocardiography confirmed TAC induced pressure-overload, leading to reduced left ventricular ejection fraction (LVEF) and diastolic dysfunction. Empagliflozin attenuated changes in LVEF (Fig. A) and improved diastolic dysfunction (data not shown). Interestingly, at 10 weeks, TAC reduced GFR, increased UACR and tended to increase renal fibrosis, which was attenuated by empagliflozin (Fig. B, C and D). To test if direct inhibition of SGLT2 in the heart and kidney is mechanistically involved, TAC surgery was repeated in SGLT2-deficient mice (SGLT2-/-). In fact, exposure to TAC resulted in comparable reduction of LVEF in SGLT2-/- mice and Empagliflozin prevented this deterioration similar to WT mice (Fig. E vs. A). Surprisingly, Empagliflozin also prevented GFR deterioration 10 weeks after TAC in mice lacking SGLT2 (SGLT2-/-) with comparable magnitude as in WT mice (Fig. F), suggesting that the reno-protective effect of Empagliflozin was independent from renal SGLT2 inhibition. The effect of empagliflozin on the heart and kidney was also investigated in patients with HF (prospective, single-arm CINNAMON-study, DRKS00031101). After 180 days of Empagliflozin treatment (10 mg), there was a significant improvement in LVEF, NT-proBNP levels and KCCQ-12 Scores (Fig. G-I) and the effects on UACR and GFR are subject of investigation. Conclusion This is the first study investigating the role of SGLT2 in Empagliflozin-dependent kidney protection of mice that develop heart failure after TAC. Importantly, empagliflozin treatment prevented deterioration of LVEF and GFR independent of the presence of SGLT2 in mice and improved cardiac markers and quality of life in patients.

Clinical characteristics and predictors of recurrence from the Australia-New Zealand Spontaneous Coronary Artery Dissection (ANZ-SCAD) registry

Abstract Background Spontaneous coronary artery dissection (SCAD) is an increasingly recognised cause of acute coronary syndrome (ACS), particularly in young women. Our understanding of SCAD remains incomplete with limited prospective data on determinants of SCAD recurrence. Purpose We aimed to describe the clinical characteristics, incidence and predictors of SCAD recurrence and major adverse cardiovascular events (MACE) in patients with SCAD from a large, multicentre registry. Methods Observational, multi-centre prospective and retrospective cohort study recruiting patients with SCAD from 23 hospitals in Australia and New Zealand. Patients aged=&amp;gt;18 years with SCAD and an ACS were eligible for inclusion. Prospectively recruited patients gave their informed consent while a waiver of consent was granted for retrospectively recruited patients. An independent core laboratory adjudicated invasive coronary angiography images to confirm the diagnosis of SCAD. The primary outcome was SCAD recurrence, defined as de novo spontaneous dissection with new ACS symptoms and cardiac enzyme elevation, not due to extension of the index lesion. Cox proportional hazard models were used to evaluate the association between SCAD recurrence and predefined clinical variables. Results From a total 487 patients recruited, 423 (132 prospective and 291 retrospective) patients with SCAD confirmed on core laboratory review were included for analysis. Mean age was 52.4±10.7 years, 89.7% were female and 73.1% were Caucasian. At discharge, 75.2% were on beta-blockers, 27.9% single antiplatelet and 61.9% dual antiplatelet (DAPT). At 15 (interquartile range 5-36) months median follow-up, SCAD recurrence occurred in 3.3%, with an overall MACE of 6.6%. On multivariate analysis, the presence of fibromuscular dysplasia (FMD) or other extra-cardiac vascular abnormalities [adjusted hazard ratio (HR) 5.63, 95% confidence interval (CI), 2.09-15.3, p&amp;lt;0.001], and past history of stroke (adjusted HR 7.99, 95% CI, 1.51-42.4, p=0.015) were associated with higher SCAD recurrence. Discharge beta-blockers was not independently associated with SCAD recurrence, while dual antiplatelet therapy that combined ticagrelor with aspirin was associated with a higher risk of recurrence (adjusted HR 2.47, 95% CI, 1.9-15.6, p=0.048). Conclusion SCAD recurrence comprised half of overall MACE in people with SCAD. The risk of SCAD recurrence was more than 5-fold higher in patients with FMD or other extra-cardiac vascular abnormalities. Dual-antiplatelet therapy that comprised ticagrelor and aspirin was associated with a higher risk of SCAD recurrence.