Search Results (358)

Ingestion of Hibiscus sabdariffa L. (HSL) provides antioxidants with beneficial effects for several pathologies with underlying oxidative stress. However, excessive, chronic consumption of the antioxidant-rich diet with HSL in healthy rats may possibly induce reductive stress (RS) with damaging effects. The aim of this study was to evaluate if the consumption of an infusion of 6% HSL for two months alters the function and structure of the myocardium. A total of 24 male Wistar rats were divided into three groups: Control (C), HSL infusion at 6% for two months (HSL 6%), and a washout group that received HSL 6% for two months followed by two months of natural water (HSL ± 6%). Myocardial performance during ischemia–reperfusion (I/R) was evaluated by using the isolated Langendorff heart model, accompanied by surface electrocardiography and histopathological analyses. Chronic 6% HSL intake increased systolic pressure (p ≤ 0.03), NrF2 expression, and elevated coronary vascular resistance, while it depressed mechanical performance and led to bradycardia and critical, extended asystolic/sinus pauses. Histopathology showed dense, permanent networks of interstitial and perivascular collagen encapsulating the hypertrophied cardiomyocytes. Chronic 6% HSL infusion was associated with myocardial structural, mechanical, and hemodynamic alterations, and with electrical changes during I/R. The washout group showed possible partial functional differences associated with withdrawal, although interpretation is limited by the longer study period. Full article

Maternal exposure to nanoplastics is a growing concern, but its effects on offspring cardiac development and the relative importance of prenatal and lactational exposure remain unclear. Pregnant C57BL/6J mice were orally exposed to 50 nm polystyrene nanoplastics at 3, 15, or 75 μg/g body weight from gestational day 1 to postnatal day 21. A cross-fostering design was used to distinguish gestational exposure from lactational exposure. Maternal polystyrene nanoplastic exposure caused dose-dependent cardiac dysfunction in offspring, including reduced ejection fraction and fractional shortening, increased myocardial injury markers, cardiomyocyte hypertrophy, and fibrosis. Cross-fostering showed that lactationally exposed offspring exhibited more severe cardiac abnormalities than offspring exposed only during gestation, indicating that the nursing period may represent a more vulnerable window. In male offspring, polystyrene nanoplastic exposure was also associated with gut microbiota dysbiosis and cardiac transcriptomic changes. Enrichment analysis identified downregulation of genes related to AMP-activated protein kinase signalling, and integrated microbiome–transcriptome analysis suggested associations between altered gut taxa and cardiac differentially expressed genes. These findings indicate that maternal polystyrene nanoplastic exposure induces offspring cardiac developmental toxicity, with stronger effects during lactation, and suggest the involvement of gut microbial and cardiac molecular remodelling. Full article

Cardiac disease is a leading cause of morbidity and early death across several lysosomal storage disorders (LSDs); however, the cardiomyopathies of Fabry, Pompe, and Danon disease are still largely treated as separate, substrate-specific disorders. We argue that they are better understood as variations on a single theme: the breakdown of the autophagy–lysosome system within cardiomyocytes. In the healthy heart, this system clears damaged proteins and organelles and is regulated by mTORC1 and the master regulator TFEB. Once lysosomal degradation or autophagosome–lysosome fusion fails, undegraded substrates and defective mitochondria accumulate, driving hypertrophy, interstitial fibrosis, and conduction disease. Danon disease, resulting from the loss of LAMP2, is the clearest example of a primary defect in autophagic flux, whereas the glycogen storage of Pompe disease and the globotriaosylceramide accumulation of Fabry disease impair flux through different upstream mechanisms that converge on the same downstream injury. The same framework extends to other storage disorders with cardiac involvement, such as mucopolysaccharidosis (MPS). We trace this shared pathobiology from molecule to bedside, examine biomarkers that reflect lysosomal and autophagic dysfunction rather than storage alone, and re-examine treatment in that light: why enzyme replacement therapy corrects substrate accumulation but leaves much of the autophagic and mitochondrial damage unresolved, and why gene therapy—particularly AAV9-LAMP2B for Danon disease—together with autophagy- and TFEB-directed strategies may help close that gap. Viewing these disorders through a single mechanistic lens reshapes how we monitor them and where future therapies should be directed. Full article

Chronic heart failure [CHF] is a progressive clinical syndrome characterized by structural and functional impairment of the myocardium, in which energy metabolic remodeling plays a central role. Increasing evidence suggests that metabolic disturbances in CHF are not only a consequence of reduced cardiac output but also active regulators of epigenetic remodeling, thereby contributing to disease progression. Key metabolites, including α-ketoglutarate, acetyl-CoA, NAD⁺, S-adenosylmethionine, succinate, and 2-hydroxyglutarate, influence the activity of DNA methyltransferases, histone-modifying enzymes, and other chromatin regulators, thereby linking metabolic status to transcriptional control. Through these mechanisms, metabolic abnormalities promote persistent activation of pathological gene programs associated with cardiomyocyte hypertrophy, fibrosis, inflammation, apoptosis, and mitochondrial dysfunction, forming a self-reinforcing metabolic–epigenetic feedback loop in CHF. Although current guideline-directed medical therapies improve symptoms and clinical outcomes, they do not directly target this metabolic–epigenetic axis. Traditional Chinese medicine (TCM), including bioactive compounds, herbal formulas, patent medicines, and injections, has demonstrated potential in preclinical studies to modulate myocardial energy metabolism, improve mitochondrial function, and influence epigenetic regulators such as SIRT1, AMPK, and TET/JmjC-dependent pathways. However, most available evidence is derived from experimental models, and causal relationships between metabolite regulation, epigenetic remodeling, and cardiac functional improvement remain insufficiently validated. This review summarizes current knowledge on metabolite-driven epigenetic regulation in CHF and evaluates emerging evidence on the role of TCM in modulating this network. We also critically discuss key limitations, including reliance on non-clinical models, incomplete pharmacokinetic understanding, and insufficient causal validation. Finally, we propose future directions based on multi-omics integration, single-cell and spatial technologies, and systems biology approaches to facilitate mechanistic clarification and translational development of metabolism-targeted strategies for CHF. Full article

Background: Oxidative stress and maladaptive cardiac remodeling are key contributors to heart failure progression. Xestospongia testudinaria, a marine sponge rich in bioactive compounds, possesses antioxidant and lipid-modulating properties. This study investigated the cardioprotective and antioxidant effects of Xestospongia testudinaria methanolic extract (Xesto) in an isoprenaline-induced rat model of heart failure. Methods: Thirty-five healthy male Wistar rats weighing 200–250 g were used in this study. Heart failure was induced in rats via subcutaneous administration of isoprenaline (10 mg/kg/day) for 14 days. Rats were subsequently treated with Xesto (15 mg/kg/day, oral gavage), digoxin (10 mg/kg/day), or saline for an additional 14 days. Hemodynamic parameters, serum NT-proBNP, oxidative stress biomarkers, biochemical indices, hematological parameters, and histopathological changes were evaluated. Molecular docking was performed to assess the interaction of Xesto constituents with Kelch-like ECH-associated protein 1 (KEAP1). Results: Isoprenaline administration significantly increased blood pressure, NT-proBNP, malondialdehyde, hepatic enzymes, and urea levels, while reducing superoxide dismutase and catalase activities. Xesto treatment significantly improved hemodynamic parameters, restored antioxidant enzyme activities, reduced lipid peroxidation, and normalized biochemical and hematological alterations. Histological analysis demonstrated reduced cardiomyocyte hypertrophy and collagen deposition in Xesto-treated rats. Docking analysis showed favorable binding of trans-phytol within the KEAP1 Kelch domain, suggesting possible modulation of antioxidant regulatory pathways. Conclusions: Xestospongia testudinaria exhibited significant cardioprotective and antioxidant effects in isoprenaline-induced heart failure, potentially through enhancement of endogenous antioxidant defenses and attenuation of pathological cardiac remodeling. These findings support its potential as a marine-derived therapeutic candidate for oxidative stress-associated cardiovascular disorders. Full article

Doxorubicin (DOX), an effective chemotherapeutic agent for many types of cancer, is known for significant cardiotoxic side effects, which largely limit its clinical usage. A 3 h treatment of cardiomyoblast H9C2 cells with a low concentration of DOX (100 nM) can induce senescence-associated β-galactosidase (SA β-gal) staining, a gold standard of cell senescence. In the current study, we comprehensively characterized the phenotype of the DOX-induced senescent cardiomyocytes for the first time. Establishing this in vitro model will facilitate an expanded capacity for searching for effective treatments for DOX-induced cell senescence. Using SA β-gal staining and cell growth rate as readouts, we assessed the concentration-dependent effect of DOX on H9C2 cell senescence. The cells were treated with DOX for 3 h and subsequently cultured for 3 days. We found that a 50 nM concentration of DOX induced ~50% SA β-gal staining and completely inhibited cell growth. The DOX-induced H9C2 cell senescence was further confirmed by several well-accepted senescence markers, including cell hypertrophy, increased p16 and p21 expression, increased Senescence Associated Secretory Phenotype (SASP) markers, arrested cell cycle, and increased ROS production. Interestingly, we found that 50 nM DOX increased mitochondrial respiration. Translationally, we found that mitochondrial-targeted tetrapeptide SS-31 (elamipretide, 1 µM) partially attenuated 50 nM DOX-induced SA β-gal staining from 51.4% to 35.8%. SS-31 also prevented increases in the p16, p21, and SASP markers and mitigated mitochondrial ROS production. Additionally, SS-31 reversed the 50 nM DOX-induced elevation of mitochondrial respiration. However, 1 µM SS-31 failed to prevent the cell cycle arrest induced by 50 nM DOX. Using a 3 h treatment of 50 nM DOX, we established an H9C2 cell senescence model. Treatment with SS-31 attenuates this DOX-induced cell senescence but not the cell cycle arrest. These data suggest that SS-31 is a promising drug to treat DOX-induced cardiomyocyte senescence. Full article

Background/Objectives: Cardiovascular disease increases with ageing and remains the leading cause of death worldwide. Cellular senescence contributes to cardiac dysfunction in the older population by secreting the senescence-associated secretory phenotype (SASP). Cardiac injury models induced by surgery have been shown to induce senescence in young adult rodents. However, surgical models are complex and associated with high mortality. Methods: We established a rat model of injury and senescence using isoproterenol (ISO). Male SD rats received ISO (100 mg/kg) for five days, then hearts were collected on days 10 and 28 after the first ISO dose. Results: ISO administration caused cardiac injury, manifested by inflammatory infiltration, fibrosis, and increased cardiomyocyte cross-sectional area. Cardiac injury was accompanied by an increase in the senescence markers SA-β-gal, p16 and p21, and DNA damage marker γH2AX. Moreover, the mRNA levels of p21 increased on day 10, along with several SASP factors, whereas the mRNA levels of p16 increased on day 28. Fibrosis, hypertrophy, and senescence persisted until day 28, indicating long-lasting cardiac remodeling and senescent cell accumulation. Conclusions: These findings suggest that ISO can provide a simple, cost-effective platform for studying senescence and cardiac injury. This model facilitates the study of timing, dosage, mechanisms and efficacy of senolytic interventions and may contribute to the development of senescence-targeted therapies. Full article

Pregnancy-associated hemodynamic overload and hormonal changes induce hypertrophy and metabolic remodeling of the maternal heart. Mitochondrial motility, mediated by ras homolog family member T (RHOT) 1 and RHOT2, is essential for cardiac adaptation to increased workload, cardiomyocyte hypertrophy, and sarcomere maturation. To test the hypothesis that Rhot1/2 expression is required for pregnancy- and postpartum-associated adaptations of the maternal heart, female mice with tamoxifen-inducible, cardiomyocyte-selective deletion of Rhot1 and Rhot2 (iRhot1/2-KO) were mated. Following gene deletion in adult mice, cardiac tissue and function were analyzed after three to five successive pregnancies and postpartum nursing periods. Age-matched nulliparous iRhot1/2-KO mice and age-matched mice expressing Rhot1 and Rhot2 served as controls. Motility of mitochondria isolated from iRhot1/2-KO hearts was impaired, as determined by the number of mobile mitochondria in an in vitro motor protein-driven single mitochondrion motility assay performed on surface-immobilized microtubules. Despite loss of Rhot1/2 expression, contractile function assessed by transthoracic echocardiography, mRNA expression of peripartum-associated heart failure markers, cardiac structure, mitochondrial morphology, mitochondrial enzymatic activity, and mitochondrial DNA content were all comparable to controls expressing Rhot1/2 at the investigated time points. RNA sequencing-based gene profiling identified a transcriptional program through which RHOT proteins preserve cardiac energetic and contraction gene expression during pregnancy and postpartum. Together, cardiomyocyte-selective loss of Rhot1/2 expression in the adult heart does not cause peripartum-associated heart failure, despite reduced cardiac energetic and contraction gene expression. Full article

Septic cardiomyopathy is recognized as an acute, transient, and reversible condition. However, septic insult may induce latent changes characteristic of cardiac remodeling, with future consequences. Therefore, the present study aimed to evaluate the morphological and functional cardiac changes in the acute and subacute phases (with 7-day follow-up) in male Wistar rats subjected to experimental sepsis using a cecal ligation and puncture (CLP) model. In the acute phase, the animals underwent echocardiographic assessment at baseline and 48 h after the induction of sepsis. In the subacute 7 days follow-up, animals were allocated in control and sepsis groups. After this period, the animals underwent echocardiographic assessment, followed by euthanasia, papillary muscle testing, and subsequent morphometric and biochemical analyses. Fecal samples from six animals per group were collected at baseline and after 7 days for microbiota analysis. In the acute phase, echocardiographic assessment revealed that, following sepsis, animals exhibited reduced systolic function. In the subacute 7 days follow-up, both echocardiogram and papillary muscles revealed cardiac dysfunction in the sepsis group. Cardiomyocyte cross-sectional area and collagen content were significantly greater in the sepsis group compared with that in the control group. Analysis of maximal enzymatic activities involved in cardiac energy metabolism and oxidative stress biomarkers revealed no significant differences between groups. Considering microbiota assessment, beta diversity analysis revealed significant differences between septic animals and controls. In conclusion, sepsis was associated with persistent systolic/diastolic dysfunction, cardiomyocyte hypertrophy, and fibrosis after 7 days. These data suggest that septic cardiomyopathy should not be considered merely an acute, transient, and reversible condition in this experimental context. Full article

Heart failure (HF) and myocardial infarction (MI) are interconnected syndromes with overlapping pathogenic pathways, including ischemia, neurohormonal activation, and maladaptive remodeling. Hypoxia-response genes, lipid-handling genes, and extracellular matrix (ECM) genes each influence these processes. Understanding their integrated roles can uncover biomarkers and targets. A systematic literature search was conducted (PubMed, Web of Science, and Scopus; 2000–2026; English-only, following PRISMA guidelines) to identify studies on key genes in hypoxia signaling, lipid metabolism, and ECM remodeling in MI/HF. Acute hypoxia (via HIFs) orchestrates metabolic adaptation and inflammation, but chronic HIF activation drives fibrosis and dysfunction. In parallel, genes controlling triglyceride and cholesterol handling (e.g., LPL, APOC3) influence energy supply and vascular risk. Variants in these genes modulate plasma lipids and MI/HF risk. For example, genetic loss-of-function in APOC3 lowers triglycerides and reduces coronary risk. ECM-related genes (e.g., COL4A1, LRP1) govern fibrosis and vascular integrity. Mutations in COL4A1 cause cardiomyocyte hypertrophy and severe fibrosis, while LRP1 regulates matrix remodeling and is upregulated in ischemic myocardium. Throughout, gene functions span acute repair versus chronic maladaptation. Findings derive from mixed sources: rodent models and cell studies demonstrate mechanistic links, while human genetics and cohorts link gene variants to HF/MI outcomes. Many promising biomarkers (e.g., circulating ITGA1) are preliminary, lacking large prospective validation. Not all cited therapeutic ideas have been tested in the treatment of human cardiac disease. The literature mix of species, models, and patient cohorts introduces heterogeneity. Full article

Type-1 ryanodine receptor (RyR1) is essential for skeletal muscle contraction. This Ca²⁺ release channel is expressed in cardiac myocytes; however, its function remains elusive. Cardiac-specific RyR1 overexpression (OE) mice were generated under the cardiac-specific Myh6 promoter. Cardiac hypertrophy (CH), cardiac functions, and mechanistic changes in RyR1 OE and control (wildtype, WT) mice were assessed using hematoxylin and eosin staining, echocardiography, electrocardiogram, quantitative RT-PCR, Western blotting, [³H]-ryanodine binding assay, confocal microscope, ROS dye Amplex Red and 2′,7′-dichlorofluorescein diacetate. RyR1 OE mice had increased whole heart, left ventricular weight, and left ventricular wall thickness, but decreased cardiac output and stroke volume, thereby presenting CH and heart failure (HF). CH markers like ANF, BNF, and aSKA mRNAs were increased in RyR1 OE heart. RyR1, but not RyR2 or RyR3, expression was increased in the RyR1 OE mouse heart. Similar results were found in mice with TAC-induced CH. RyR1, but not RyR2 mRNA, was increased in cardiac muscle from dogs and humans with CH and/or HF. Maximum [³H]-ryanodine binding was increased, whereas the binding dissociation constant decreased in left ventricular cardiomyocytes from RyR1 OE mice. RyR2-dependent Ca²⁺ sparks were increased, which was blocked by riluzole, a small molecule known to inhibit RyR2. Consistently, ROS was remarkably increased in RyR1 OE cardiac cells. We first generated cardiac-specific RyR1 OE mice; these mice had CH, HF, and increased RyR1 expression with no RyR2 or RyR3 alteration. Similar changes were observed in mice, dogs, and humans with CH and HF. Increased mitochondrial ROS-dependent RyR2 Ca²⁺ release was essential for RyR1-induced CH and HF. Full article

Background: Atrial fibrillation (AF) is a common clinical arrhythmia associated with mitochondrial dysfunction, oxidative stress, and atrial fibrosis. Mitochondrial-derived peptides (MDPs), including humanin (HN) and MOTS-c, exhibit cytoprotective properties, but their role in AF remains largely unknown. Objective: This study aimed to investigate the expression of HN and MOTS-c in AF patients and to evaluate their therapeutic potential and underlying mechanisms in an AngII-induced mouse model and primary cardiac cells. Methods: HN and MOTS-c expression in human atrial tissues was analyzed using public GEO data, immunohistochemistry, and immunofluorescence. Plasma levels were measured in a matched cohort (39 AF patients, 39 sinus rhythm controls). Murine AF models (male C57BL/6J mice, n = 36) and primary rat cardiomyocytes and fibroblasts were exposed to angiotensin II (AngII) with or without treatment with HNG (an HN analogue) or MOTS-c. Results: HN and MOTS-c were significantly downregulated in human AF atrial tissue, and their levels inversely correlated with fibrosis extent. Plasma MOTS-c was decreased in AF patients and inversely correlated with NT-proBNP. In vivo, HNG or MOTS-c treatment reduced AF inducibility and attenuated AngII-induced atrial fibrosis and hypertrophy. Peptide treatment was associated with improved mitochondrial ultrastructure, reduced mitochondrial fission proteins (Drp1, Fis1), and lower pro-inflammatory cytokines (IL-1β, IL-6) in mouse atria. In primary cardiomyocytes, both peptides mitigated AngII-induced oxidative stress. In fibroblasts, they directly inhibited AngII-induced activation, proliferation, and migration. Exploratory RNA-seq suggested that HNG predominantly affects cell adhesion pathways, while MOTS-c acts on metabolic processes. Conclusions: Downregulation of HN and MOTS-c in human AF is associated with disease severity. In murine models, HNG or MOTS-c administration attenuates atrial fibrosis and mitochondrial dysfunction and reduces AF inducibility. These findings suggest that MDPs may represent a novel therapeutic avenue for AF, although further validation with larger cohorts and mechanistic studies are required. Full article

Pathological cardiac hypertrophy is an important risk factor for cardiovascular disease. Ganoderic acid A (GAA), the primary bioactive constituent of Ganoderma lucidum (G. lucidum), is known for its stable chemical properties and diverse biological activities. It has been shown to confer protection against myocardial ischemia–reperfusion injury in rat models, potentially through modulating inflammatory responses and inhibiting protein expression linked to both NF-κB and apoptosis pathways. Nevertheless, the role of GAA in cardiac hypertrophy has not yet been fully elucidated. Using transverse aortic constriction (TAC)-induced cardiac hypertrophy in mice, we analyzed the degree of hypertrophy using echocardiography and at the pathology and molecular levels. Our results demonstrate that GAA effectively attenuates Ang II-induced cardiomyocyte hypertrophy in vitro and reduces pressure overload-induced cardiac hypertrophy in vivo. Further investigation revealed that GAA exerts its anti-hypertrophic effects by downregulating the mRNA expression of hypertrophic and fibrotic markers and attenuating inflammatory responses, and that the protective effects of GAA may involve NF-κB signaling. This study provides valuable theoretical support for the potential therapeutic application of GAA in treating pathological myocardial hypertrophy and heart failure. Full article

Kv11.1 (hERG1) channels, encoded by KCNH2, mediate the rapid delayed rectifier potassium current (I_Kr) crucial for cardiac repolarization. Disruptions, via mutations or antiarrhythmic drugs like dofetilide cause severe arrhythmogenic disorders, including Long QT Syndrome Type 2 (LQT2), Brugada Syndrome (BrS), and Torsades de Pointes (TdP). While Kv11.1’s role in channelopathies and drug-induced arrhythmias is established, understanding its complex regulation and therapeutic targeting remains a challenge. This review synthesizes the structural, functional, and regulatory aspects of Kv11.1 channels and their clinical implications. Recent studies using iPSC-derived cardiomyocytes highlight regulation by PI3K/Akt, PKC, and PKA signaling via phosphorylation (Ser283, Ser890) and interactions with proteins like 14-3-3. Beyond electrophysiology, Kv11.1 influences pathological hypertrophy and non-cardiac functions including insulin secretion. Pharmacological efforts focus on activators to shorten action potential duration and suppress TdP, and blockers with overdose risks. Mutation heterogeneity, exemplified by trafficking impairment (G785D) in LQT2 and gain-of-function (R397C) in BrS, complicates precision therapy. Clinically, systematic risk stratification using electrocardiographic parameters and genotype-specific approaches enables personalized management. Beta-blockers remain first-line therapy for LQTS2, while rigorous avoidance of QT-prolonging medications and electrolyte monitoring form the cornerstones of preventive care. Advancing Kv11.1-targeted therapies with approaches like CRISPR-Cas9 and pharmacological chaperones (e.g., lumacaftor) holds promise for personalized treatments, ultimately reducing arrhythmic events and sudden cardiac death. Full article

Pathological cardiac hypertrophy is a critical factor leading to cardiomyopathy and ultimately heart failure. While several signaling pathways controlling cardiac hypertrophy have been identified, the molecular mechanisms underlying their precise regulation remain incompletely understood. Strip1, a structural component of STRIPAK complexes, has been implicated in various cellular functions; however, its role in cardiomyocytes is uncharacterized. Here we identify Strip1 as a potent anti-hypertrophic factor, controlling cell size and the hypertrophic gene program in neonatal rat ventricular cardiomyocytes (NRVCMs). STRIP1 expression was found to be significantly reduced in human dilated and ischemic cardiomyopathies (DCM/ICM), as well as in murine stress model induced by transverse aortic constriction (TAC). In a knockdown model with morpholino-driven STRIP1 reduction in zebrafish in vivo, impaired cardiac function and heart failure–like features were observed. Interestingly, Strip1 localized to the nucleolus in NRVCMs, suggesting a putative nuclear/epigenetic role in cardiomyocytes. Furthermore, our data support association of Strip1 with cardiac STRIPAK complex, modulating kinase activities, including MST1/MST2 and MST4. Mechanistically, Strip1 appears to influence prohypertrophic signaling, including Hippo- and Calcineurin/NFAT-related pathways, which may contribute to pathological cardiac remodeling. Collectively, these findings establish Strip1 as an important modulator of cardiomyocyte hypertrophy and a potential therapeutic target for cardiomyopathy and heart failure. Full article