Search Results (668)

Cardiovascular diseases remain a growing concern worldwide. Hence, it is critical to understand cardiac development and disease in a relevant human-based in vitro model. Human cardiac organoids are an alternative approach to studying cardiogenesis, in the context of cell–cell communication, and disease etiology, using human induced pluripotent stem cells (hiPSCs). Extracellular vesicles (EVs) are nanosized particles harboring proteins, nucleic acids, and metabolites and are implicated in intercellular communication. Since cardiac development requires a complex interplay between several cell types, we hypothesize that EVs may mediate this communication. Here, we isolated EVs from hiPSC-derived cardiac organoids (cardEVs). LC-MS/MS was performed to analyze their protein cargo and compare it with those from a cardiomyocyte cell line (AC10 CM EVs) and from human heart explants of cadaveric donors (heEVs) using a bioinformatic approach. cardEVs share 48.9% of their proteins with heEVs, with important biological processes such as “Metabolism” and “Cardiac Function” highlighted in both proteomes. This overlap between the proteomes of cardEVs and heEVs suggests a molecular similarity between the two models. Therefore, we reiterate the importance of cardiac organoids as an excellent model for studying cardiac development and disease modeling, as well as to explore the complexity of intercellular communication. Full article

For the past decade, cell-based therapies have been the focus of research to investigate their potential to treat ischemic heart disease. The translation to human clinical studies depends on the demonstration of therapeutic efficacy and safety, particularly when transplanted in the subacute and chronic post-MI phase. A number of studies were identified that reported the effect of hiPSC-CMs on cardiac outcomes when transplanted at least 7 days post-myocardial infarction. The mean sample size of the published studies was 30 (±17) animals with a mean follow-up duration of 51 (±37) days. hiPSC-CM transplantation enhanced systolic function through augmented myocardial contractility, decreased infarct size, attenuated ventricular remodeling, and enhanced angiogenesis in the infarct and border zones in both small and large animal models. This effect was enhanced by co-transplantation with cells of vascular or adipose origin and is associated with high expression of VEGF in most studies. Despite this effect, transplanted hiPSC-CMs were structurally immature with limited survival at the endpoint. Epicardial delivery was associated with better efficacy outcomes and lower rates of arrhythmia. No study reported teratoma formation or immune rejection. From the current literature, there appears to be no consensus on the extent to which hiPSC-CMs improved systolic function, nor the degree to which this arises directly from integration of the new myocardium or from a paracrine-mediated mechanism. The nature of this paracrine mechanism and ways to improve the maturity and survival of implanted cardiomyocytes are issues that have yet to be resolved. In summary, while therapeutic benefit from cell therapy is clear, further research is required to establish whether the key mechanisms require a cellular component. Full article

Cardiovascular diseases (CVDs) have emerged as a common health problem. However, despite their prevalence, little progress has been made in their treatment. In recent years, neurotrophic factors (NTFs) have been discovered to exert cardioprotective functions for CVDs. NTFs can modulate vascular integrity, myocardial remodeling, angiogenesis, and autonomic regulation, playing the roles of maintaining cardiovascular homeostasis and influencing disease progression. Under pathological conditions, the supplement of NTFs can induce substantial adaptations to mitigate adverse cardiac responses. Several NTFs have been investigated in this regard. This review briefly elaborates on present insights into the expression, signaling pathways, and regulatory effects of NTFs on the development of CVDs, and also discusses emerging therapeutic strategies based on NTFs, ranging from exercise to advanced modalities including stem cell therapy, gene transfer, recombinant protein therapy and NTF mimetics, among which the mimetics and exercise interventions emerge as the most promising avenues for clinical translation. Full article

Background: Chronically non-healing thoracic wounds after cardiac and non-cardiac thoracotomy, including cases when coronary artery bypass grafting (CABG) is performed, represent a great clinical challenge. It is often that a conservative treatment of the wounds does not provide effective regeneration of the damaged tissues. It is especially critical in patients with infected wounds, in patients owning a systemic infection, and in elderly people. Methods: The article presents a case report of successful treatment of a 63-year-old man with refractory chronic osteomyelitis of the sternum and mediastinitis four years after CABG, complicated by COVID-19 at the time of reconstructive surgery. Due to the low effectiveness of conservative treatment methods, a two-stage approach was applied: radical surgical wound debridement followed by infiltration of the wound with allogenic mesenchymal stromal cells (MSCs) of Wharton’s jelly (WJ-MSCs). Results: This double-stage therapy successfully modulated the inflammatory environment and stimulated granulation, facilitating final thoracoplasty and osteosynthesis. The patient achieved complete healing of the sternum, demonstrating benefits of WJ-MSCs in treating conservative treatment-resistant infections in the surgical wound. Conclusions: The advantages of using perinatal mesenchymal stem cells, with WJ-MSCs as a type of this class of MSCs, were demonstrated in treating chronically infected sternal surgical wounds. We also compared their regenerative properties to other stem cell types like bone marrow MSCs. Full article

Human adult cardiomyocytes (CMs) have limited regenerative capacity, posing a significant challenge in restoring cardiac function following substantial CM loss due to an acute ischemic event or chronic hemodynamic overload. Nearly half of patients show no improvement in left ventricular ejection fraction during recovery from acute myocardial infarction. At baseline, both humans and mice exhibit low but continuous cell turnover originating from the existing CMs. Moreover, myocardial infarction can induce endogenous CM cell cycling. Consequently, research has focused on identifying drivers of CM rejuvenation and proliferation from pre-existing CMs. High-throughput screening has facilitated the discovery of novel pro-proliferative targets through small molecules, microRNAs, and pathway-specific interventions. More recently, omics-based approaches such as single-nucleus RNA sequencing and spatial transcriptomics have expanded our understanding of cardiac cellular heterogeneity. The big-data strategies provide critical insights into why only a subset of CMs re-enter the cell cycle while most remain quiescent. In this review, we compare several high-throughput screening strategies used to identify novel targets for CM proliferation. We also summarize the benefits and limitations of various screening models—including zebrafish embryos, rodent CMs, human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs), and cardiac organoids—underscoring the importance of integrating multiple systems to uncover new regenerative mechanisms. Further work is needed to identify translatable and safe targets capable of inducing functional CM expansion in clinical settings. By integrating high-throughput screening findings with insights into CM heterogeneity, this review provides a comprehensive framework for advancing cardiac regeneration research and guiding future therapeutic development. Full article

Cardiac hypertrophy is an important risk factor for heart failure and is often accompanied by contractile dysfunction. While hypertrophic growth contributes to disease progression, the underlying molecular mechanisms remain incompletely understood. A proposed contributor is a metabolic shift toward glucose uptake, suggesting that kinases regulating this process, such as protein kinase D1 (PKD1) and downstream target phosphatidylinositol 4-kinase IIIβ (PI4KIIIβ), might be effective targets to mitigate cardiac hypertrophy-induced contractile dysfunction. We investigated whether PI4KIIIβ inhibition downregulates enhanced glucose uptake in hypertrophic cardiomyocytes and thereby treats cardiac hypertrophy-induced contractile dysfunction. Hypertrophy was induced in cultured adult rat cardiomyocytes and human stem cell-derived cardiomyocytes using either phenylephrine (PE) or adenoviral PKD1 overexpression. PE-induced hypertrophy was associated with increased mRNA expression of BNP, activation of hypertrophic signaling, morphological alterations, enhanced protein synthesis and glucose uptake, and impaired contractile function. Treatment with the PI4KIIIβ inhibitor MI14 prevented and reversed PE-stimulated glucose uptake and contractile dysfunction, while hypertrophic signaling, cell size, and protein synthesis remained unaffected. Similar effects on glucose uptake were observed in the PKD1 overexpression model. These findings suggest that targeting myocardial substrate metabolism via the PI4KIIIβ pathway, rather than hypertrophic growth itself, could be a promising strategy to treat hypertrophy-induced contractile dysfunction. Full article

Human induced pluripotent stem cells (hiPSCs) offer significant potential for differentiation and research applications in cardiovascular diseases. When induced differentiated hiPSC-derived cardiomyocytes (hiPSC-CMs) are transplanted into the infarcted myocardial region, they exhibit extremely low survival rates and unsatisfactory therapeutic effects due to ischemia, hypoxia, and immune inflammation in the surrounding environment. To address this issue, we used Panax notoginseng saponin R1 (NGR1), which has demonstrated significant protective effects in prior research, to pretreat hiPSC-CMs before transplantation. Utilizing an in vitro H₂O₂ oxidative stress model and a nude mouse myocardial infarction (MI) model, we investigated the mechanism through which NGR1 pretreatment enhances the therapeutic efficacy of hiPSC-CM transplantation. The results revealed that the hiPSC-CMs expressed cTnT. NGR1 did not promote the proliferation of hiPSC-CMs but instead induced elevated levels of p-Akt protein in these cells. Compared to hiPSC-CM transplantation alone, transplantation of hiPSC-CMs pretreated with NGR1 exhibited higher ejection fraction (EF) and fractional shortening (FS) values, along with reduced infarct size and collagen deposition. Additionally, there were more HNA-positive cardiomyocytes in the cardiac tissue, fewer TUNEL-positive signals, and increased VWF-positive and Lyve1-positive signals. Furthermore, the gene expression levels of VEGFC, IGF-1, and SDF-1 were higher. Therefore, NGR1 pretreatment improves the survival of transplanted hiPSC-CMs in tissues, reduces myocardial apoptosis, enhances cardiac function, decreases infarct size and collagen deposition, promotes angiogenesis and lymphangiogenesis, and stimulates paracrine secretion. Full article

Microfluidic technologies have ushered in a new era in cardiac tissue engineering, providing more predictive in vitro models compared to two-dimensional culture studies. This review examines Organ-on-a-Chip (OoC) and Lab-on-a-Chip (LoC) platforms, with a specific focus on cardiovascular applications. OoCs, and particularly Heart-on-a-Chip systems, have advanced biomimicry to a higher level by recreating complex 3D cardiac microenvironments in vitro and dynamic fluid flow. These platforms employ induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs), engineered extracellular matrices, and dynamic mechanical and electrical stimulation to reproduce the structural and functional features of myocardial tissue. LoCs have introduced miniaturization and integration of analytical functions into compact devices, enabling high-throughput screening, advanced diagnostics, and efficient pharmacological testing. They enable the investigation of pathophysiological mechanisms, the assessment of cardiotoxicity, and the development of precision medicine approaches. Furthermore, progress in multi-organ systems expands the potential of microfluidic technologies to simulate heart–liver, heart–kidney, and heart–tumor interactions, providing more comprehensive predictive models. However, challenges remain, including the immaturity of iPSC-derived cells, the lack of standardization, and scalability issues. In general, microfluidic platforms represent strategic tools for advancing cardiovascular research in translation and accelerating therapeutic innovation within precision medicine. Full article

Ischemic heart disease remains the leading cause of cardiovascular mortality worldwide. In myocardial infarction (MI), extracellular vesicles (EVs)—particularly small EVs (sEVs)—transport therapeutic cargo such as miR-21-5p, which suppresses apoptosis, and other proteins, lipids, and RNAs that can modulate cell death, inflammation, angiogenesis, and remodeling. This review synthesizes recent mechanistic and preclinical evidence on native and engineered EVs for post-MI repair, mapping therapeutic entry points across the MI timeline (acute injury, inflammation, and healing) and comparing EV sources (stem-cell and non-stem-cell), administration routes, and dosing strategies. We highlight engineering approaches—including surface ligands for cardiac homing, rational cargo loading to enhance potency, and biomaterial depots to prolong myocardial residence—that aim to improve tropism, durability, and efficacy. Manufacturing and analytical considerations are discussed in the context of contemporary guidance, with emphasis on identity, purity, and potency assays, as well as safety, immunogenicity, and pharmacology relevant to cardiac populations. Across small- and large-animal models, EV-based interventions have been associated with reduced infarct/scar burden, enhanced vascularization, and improved ventricular function, with representative preclinical studies reporting approximately 25–45% relative reductions in infarct size in rodent and porcine MI models, despite substantial heterogeneity in EV sources, formulations, and outcome reporting that limits cross-study comparability. We conclude that achieving clinical translation will require standardized cardiac-targeting strategies, validated good manufacturing practice (GMP)-compatible manufacturing platforms, and harmonized potency assays, alongside rigorous, head-to-head preclinical designs, to advance EV-based cardiorepair toward clinical testing. Full article

The aim of this study was to determine whether exosomes from Nicotinamide phosphoribosyltransferase (NAMPT)-overexpressing mesenchymal stem cells (MSC NAMPT-Exo) can attenuate aortic stenosis (AS) and explored the underlying mechanism. NAMPT expression was examined in EC CXCR4 KO (AS) mouse hearts. Six-week-old AS mice received weekly injections of NAMPT-Exo, MSC-Exo, or PBS for three weeks, followed by echocardiography and histological examination of the valves (H&E, Alizarin Red, immunofluorescence). Cardiac ECs from control, AS, and NAMPT-Exo-treated mice were analyzed for miRNA expression (miR-146a-3p/5p, miR-125b-5p, miR-142a-5p). NAMPT expression was decreased in AS hearts. Treatment with NAMPT-Exo reduced aortic valve peak velocity, valvular thickening, and microcalcifications, while improving ejection fraction, fractional shortening, and ventricular dimensions. AS endothelial cells showed elevated levels of miR-146a-3p, miR-146a-5p, and miR-142a-5p, NAMPT-Exo specifically normalized miR-146a-3p. Histology revealed EndMT in AS valves, which was diminished by NAMPT-Exo. In vitro, inhibiting miR-146a-3p suppressed TGF-β-induced EndMT. Our results demonstrate that NAMPT-enriched MSC-derived exosomes effectively slow the progression of AS. Additionally, our findings highlight miR-146a-3p as a key regulator of EndMT, suggesting it as a potential molecular target for future therapies. Full article

Cell-free therapy is gaining increasing interest among researchers as an alternative to mesenchymal stem/stromal cell (MSC) therapy. Since the therapeutic effects of MSCs rely predominantly on their paracrine activity, the use of their secretome as a therapeutic agent in broadly defined regenerative medicine, including cardiac regeneration, appears to be a rational approach. In this review, we discuss recent studies that employed secretomes derived from various types of MSCs in cardiomyocyte regeneration following myocardial infarction (MI). Special attention is given to the protein components of the secretome, which may drive tissue repair, and methods of priming the MSC to achieve secretome composition tailored for heart regeneration. Finally, we summarize recent preclinical findings on the effects of MSC secretomes on cardiomyocyte regeneration. Full article

Background/Objectives: Cardiotoxicity remains a leading cause of drug withdrawal. Conventional preclinical models, such as two-dimensional (2D) cell cultures and animal studies, often fail to accurately predict human cardiac responses. While 2D cultures lack the complex architecture and dynamic functionality of native myocardium, interspecies differences limit the translational relevance of animal models. The objective of this study was to develop a human-relevant, in vitro platform that enables predictive and functional assessment of drug-induced cardiotoxicity. Methods: Here, we present a high-throughput in vitro platform for cardiotoxicity screening using three-dimensional (3D) cardiac tissues derived from human induced pluripotent stem cells (hiPSCs) within a thermoresponsive extracellular matrix-derived hydrogel. The hydrogel enables homogeneous encapsulation, differentiation in 3D, and long-term assembly into a functional cardiac tissue. Maturation was validated by immunostaining for cardiac-specific markers, and calcium imaging was employed to monitor electrical signal propagation. Contractile performance, defined by beat rate and contraction amplitude, was quantified using video-based motion analysis. The platform was applied to evaluate the dose-dependent effects of various cardioactive compounds, including β-adrenergic agonists ((-) epinephrine and dopamine), a cardiotoxic chemotherapeutic (doxorubicin), a sinus node inhibitor (ivabradine), a calcium channel blocker (verapamil), and a β-adrenergic antagonist (metoprolol). Results: The engineered cardiac tissues exhibited functional maturation and stable contractile behavior. Drug testing demonstrated compound-specific, dose-dependent functional responses. For each compound, the system faithfully reproduced the expected physiological responses. Conclusions: This human-relevant, scalable platform enables sensitive, multiparametric functional assessment of cardiac tissues, offering a cost-effective and predictive tool for preclinical drug safety testing. By bridging the gap between in vitro assays and human physiology, it holds promise to enhance translational accuracy while reducing reliance on animal models. Full article

Mesenchymal stem cells (MSCs) are pivotal in regenerative medicine due to their high differentiation potential and therapeutic versatility. MSCs are multipotent cells capable of differentiating into adipocytes, chondroblasts, osteoblasts, and, under specific conditions, neural, myocyte, and epidermal lineages. This cell type contributes to tissue repair, immunomodulation, and regenerative therapies for cardiac, orthopedic, and hematological disorders. Accurate identification and characterization of these stem cells are essential for both research and clinical applications. MSCs are typically defined by plastic adherence, expression of surface markers CD105, CD73, and CD90, low or absent expression of hematopoietic markers (CD45, CD34), and in vitro differentiation potential. Understanding the expression patterns and functional relevance of these surface markers is critical for improving isolation strategies, enhancing therapeutic efficacy, and minimizing adverse effects. This review provides a comprehensive overview of the principal surface markers of MSCs, highlighting their significance in stem cell biology and clinical translation. Full article

Drug-induced cardiotoxicity (DICT) severely hampers drug development and threatens patient safety. Together with the growing global burden of cardiovascular disease, there is an urgent need to establish more predictive preclinical models. Recently, human pluripotent stem cell-derived cardiac organoids (hCOs) have emerged as a promising three-dimensional in vitro model, achieving significant progress in simulating the complex structure and function of the human heart. However, existing reviews predominantly focus on technical construction or specific applications, lacking an integrated discussion of pathological model construction and their use under evolving regulatory frameworks. This review distinguishes itself by proposing a novel, holistic framework that bridges “construction technology,” “pathological modeling,” and “application evaluation.” We systematically categorize and summarize three major strategies for building hCO-based pathological models: patient-specific, gene-edited, and microenvironment-modulated approaches. Furthermore, we highlight the unique advantages of hCOs in preclinical drug assessment and detail their cutting-edge applications in early DICT warning, metabolism-related safety evaluation, and personalized drug evaluation. Finally, we address current challenges, including maturation and standardization, and outline future directions involving integration with organ-on-a-chip technology and artificial intelligence. This review aims to provide a theoretical foundation and roadmap toward more reliable and human-relevant drug development paradigms. Full article

Hypertrophic cardiomyopathy (HCM) is a common and deadly cardiac disease characterized by enlarged myocytes, increased myocardial wall thickening, and fibrosis. A majority of HCM cases are associated with mutations in the β-myosin heavy chain (MYH7) converter domain locus, which leads to varied pathophysiological and clinical manifestations. Using base-editing technology, we generated mutant human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) harboring HCM-causing myosin converter domain mutations (MYH7 c.2167C>T [R723C]; MYH6 c.2173C>T [R725C]) to define HCM pathogenesis in vitro. In this study, we integrated transcriptomic analysis with phenotypic and molecular analyses to dissect the HCM disease mechanisms using MYH6/7 myosin mutants. Our KEGG analysis of bulk RNA-sequencing data revealed significant upregulation of transcripts associated with HCM in the mutant hiPSC-CMs. Further, in-depth transcriptomic analysis using Gene-Ontology (GO-term) analysis for biological process showed upregulation of several transcripts associated with heart development and disease. Notably, our analysis showed robust upregulation of cytoskeletal transcripts, including actin-cytoskeleton networks, sarcomere components, and other structural proteins in the mutant CMs. Furthermore, cellular and nuclear morphological analysis showed that the MYH6/7 mutation induced cellular hypertrophy and increased aspect ratio compared to the isogenic control. Immunostaining experiments showed marked sarcomere disorganization with lower sarcomeric order and higher dispersion in the mutant hiPSC-CMs, highlighting the remodeling of the myofibril arrangement. Notably, the MYH6/7 mutant showed reduced cortical F-actin expression and increased central F-actin expression compared to the isogenic control, confirming the cytoskeletal remodeling and sarcomeric organization during HCM pathogenesis. These pathological changes accumulated progressively over time, underscoring the chronic and evolving nature of HCM driven by the MYH6/7 mutations. Together, our findings provide critical insights into the cellular and molecular underpinnings of MYH6/7-mutation-associated disease. These findings offer valuable insights into HCM pathogenesis, aiding in future therapies. Full article