Current myocardial infarction (MI) treatment strategies remain challenged in suboptimal pharmacokinetics and potential adverse effects. Here we present a bioelectronic interface capable of producing on-demand abundant bioactive extracellular vesicles (EVs) near the MI area for in-situ localized treatment. The technology, termed electroactive patch for wirelessly and controllable EV generation (ePOWER), leverages wireless bioelectronic patch to stimulate embedded electrosensitive macrophages, actively modulating the biosynthesis of EVs and enabling EV production with high programmability to be delivered directly to the MI area. ~2400% more bioactive EVs were produced per cell under our ePOWER system. When surgically implanted, we demonstrate the therapeutic potential of in-situ EV production system to alleviate MI symptoms and improve cardiac function. This programmable ePOWER technology enables in-situ production of therapeutically rich EVs, thus reducing the need for exogenous cell expansion platforms and dedicated delivery, holding promise as a therapeutic all-in-one platform to treat various diseases.

Macrophages play a crucial role in cardiac remodeling and prognosis after myocardial infarction (MI). Our previous studies have built a scalable method for preparing scaled stem cell nanovesicles (NVs) and demonstrated their remarkable reparative effects on ischemic heart disease. To further enhance the targeted reparative capabilities of the NVs toward injured myocardium, we employed a dual modification strategy involving platelet membrane coating and miR-181a-5p loading, creating a nanovesicle termed P-181-NV. This study aimed to investigate the efficacy of P-181-NV in targeted reparative interventions for damaged myocardium and to reveal the underlying mechanisms involved. After successful construction and characteristic analysis of P-181-NV, the in vivo tracking techniques demonstrated a significant enhancement in the targeting capacity of P-181-NV toward the injured myocardium. Moreover, P-181-NV showed marked improvements in cardiac function and remodeling as observed through ultrasound echocardiography and Masson's trichrome staining. Furthermore, P-181-NV significantly augmented myocardial cell viability, angiogenic potential, and the polarization ratio of the anti-inflammatory macrophages. The findings of this study underscore the pivotal role of platelet-membrane-coated and miR-181a-5p modified stem cell nanovesicles in facilitating postmyocardial infarction cardiac repair. By modulating macrophage polarization, P-181-NV offers a promising approach for enhancing the efficacy of targeted reparative interventions for damaged myocardium. These results contribute to our understanding of the potential of nanovesicles as therapeutic agents for cardiac repair and regeneration, presenting avenues for future research and clinical applications.

Myocardial infarction (MI) is the most common cardiovascular disease (CVD) and the leading cause of mortality worldwide. Recent advancements have identified human endometrial mesenchymal stem cells (hEnMSCs) as a promising candidate for heart regeneration, however, challenges associated with cell-based therapies have shifted focus toward cell-free treatments (CFTs), such as exosome therapy, which show considerable promise for myocardial tissue regeneration. MI was induced in male Wistar rats by occluding the left anterior descending (LAD) coronary artery. The hEnMSCs-derived exosomes (hEnMSCs-EXOs) were encapsulated in injectable fibrin gel inside the cardiac tissue. The encapsulated hEnMSC-EXOs were administered, and their effects on myocardial regeneration, angiogenesis, and heart function were monitored for 30 days post-MI. The treatments were evaluated through histological analysis, echocardiographic parameters of left ventricular internal dimension at end-diastole (LVIDD) and end-systole (LVID), left ventricular end-diastole volume (LVEDV), left ventricular end-systole volume (LVESV), and left ventricular ejection fraction (LVEF) and molecular studies. Histological findings demonstrated significant fibrosis and left ventricular remodeling following MI. Treatment with fibrin gel-encapsulated hEnMSCs-EXOs substantially reduced fibrosis, enhanced angiogenesis, and prevented heart remodeling, leading to improved cardiac function. Notably, 30 days after encapsulated hEnMSCs-EXOs were delivered corresponded with a less inflammatory microenvironment, supporting cardiomyocyte retention in ischemic tissue. This study highlights the potential of encapsulated hEnMSCs-EXOs in fibrin gel as a novel therapeutic strategy for ischemic myocardium repair post-MI. The findings underscore the importance of biomaterials in advancing stem cell-based therapies and lay a foundation for clinical applications to mitigate heart injury following MI.

Neonatal mammalian hearts are capable of regenerating by inducing cardiomyocyte proliferation after injury. However, this regenerative capability in adult mammalian hearts almost disappears. Extracellular vesicles (EVs) have been shown to play vital cardioprotective roles in heart repair. Here, we report that EVs from regenerating neonatal heart tissues, after apical resection surgery (AR-Neo-EVs), exhibit stronger pro-proliferative, anti-apoptotic, and pro-angiogenesis activities than EVs from neonatal mouse cardiac tissues (Neo-EVs), effects which are absent in adult mouse heart-derived EVs (Adu-EVs). Proteomic analysis reveals the expression of Wdr75 protein, a regulator of p53, is higher in AR-Neo-EVs than in Neo-EVs. It is shown the regenerative potential of AR-Neo-EVs is abrogated when Wdr75 is knocked down. We further show that delivery of AR-Neo-EVs by sodium alginate hydrogel microspheres is an effective treatment in myocardial infraction. This work shows the potential of using EVs from regenerating tissue to trigger protective and regenerative mechanisms.

Extracellular vesicles (EVs) are secreted from biological cells and contain many molecules with diagnostic values or therapeutic functions. There has been great interest in academic and industrial communities to utilize EVs as tools for diagnosis or therapeutics. In addition, EVs can also serve as delivery vehicles for therapeutic molecules. An indicator of the enormous interest in EVs is the large number of review articles published on EVs, with the focus ranging from their biology to their applications. An emerging trend in EV research is to produce and utilize "engineered EVs", which are essentially the enhanced version of EVs. EV engineering can be conducted by cell culture condition control, genetic engineering, or chemical engineering. Given their nanometer-scale sizes and therapeutic potentials, engineered EVs are an emerging class of nanomedicines. So far, an overwhelming majority of the research on engineered EVs is preclinical studies; there are only a very small number of reported clinical trials. This Review focuses on engineered EVs, with a more specific focus being their applications in therapeutics. The various approaches to producing engineered EVs and their applications in various diseases are reviewed. Furthermore, in vivo imaging of EVs, the mechanistic understandings, and the clinical translation aspects are discussed. The discussion is primarily on preclinical studies while briefly mentioning the clinical trials. With continued interdisciplinary research efforts from biologists, pharmacists, physicians, bioengineers, and chemical engineers, engineered EVs could become a powerful solution for many major diseases such as neurological, immunological, and cardiovascular diseases.

Cardiac fibrosis, a key contributor to ventricular pathologic remodeling and heart failure, currently lacks effective therapeutic approaches.

Small extracellular vesicles from young healthy human plasma (Young-sEVs) were characterized via protein marker, transmission electron microscopy, and nanoparticle tracking analysis, then applied in cellular models and mouse models of cardiac fibrosis. Western blotting and qRT-PCR were used to identify protective signaling pathways in cardiac fibroblasts (CFs).

Young-sEVs significantly inhibited cardiac fibrosis and subsequent cardiac dysfunction post-myocardial infarction (MI) in mice. The main findings included that echocardiographic assessments four weeks post-MI indicated that Young-sEVs improved left ventricular ejection fraction (LVEF) and fractional shortening (LVFS), and reduced left ventricular internal diameter in diastole (LVIDd) and systole (LVIDs). Treatment with Young-sEVs also decreased Masson-positive fibroblast areas and collagen synthesis in cardiac tissue. However, sEVs from the old control group did not achieve the above effect. Consistent with in vivo results, Young-sEVs could also inhibit the proliferation, migration, and collagen synthesis of CFs in the TGF-β1-induced cellular fibrosis model. High-throughput microRNA (miRNA) sequencing and qRT-PCR analysis revealed that miR-664a-3p was abundant in Young-sEVs. The high expression of miR-664a-3p significantly inhibited the proliferation, migration, and collagen synthesis of TGF-β1-induced CFs. However, suppressing the expression of miR-664a-3p in Young-sEVs eliminated their therapeutic effect on cardiac fibrosis in mice. Further studies confirmed SMAD4 as a direct downstream target of miR-664a-3p, whose overexpression could reverse the anti-fibrotic effects of miR-664a-3p.

In summary, these findings firstly revealed that Young-sEVs could directly bind to the 3'-untranslated region of SMAD4 mRNA through miR-664a-3p, thereby inhibiting the TGF-β/SMAD4 signaling pathway to protect heart from fibrosis and improve cardiac function. Considering the ease of obtaining plasma-derived sEVs, our study offers a promising therapeutic strategy for heart failure, with the potential for rapid clinical translation in the near future.

Cardiac hypertrophy is an adaptive response to pressure or volume overload such as hypertension and ischemic heart diseases. Sustained cardiac hypertrophy eventually leads to heart failure. The pathophysiological alterations of hypertrophy are complex, involving both cellular and molecular systems. Understanding the molecular events that inhibit or repress cardiac hypertrophy may help identify novel therapeutic strategies. Increasing evidence has indicated that extracellular vesicle (EV)-derived microRNAs (miRNAs) play a significant role in the development and progression of cardiac hypertrophy. In this review, we briefly review recent advancements in EV research, especially on biogenesis, cargoes and its role in cardiac hypertrophy. We then describe the latest findings regarding EV-derived miRNAs, highlighting their functions and regulatory mechanisms in cardiac hypertrophy. Finally, the potential role of EV-derived miRNAs as targets in the diagnosis and treatment of cardiac hypertrophy will be discussed.

Extracellular vesicles (EVs) are associated with intercellular communications, immune responses, viral pathogenicity, cardiovascular diseases, neurological disorders, and cancer progression. EVs deliver proteins, metabolites, and nucleic acids into recipient cells to effectively alter their physiological and biological response. During their transportation from the donor to the recipient cell EVs face differential ionic concentrations, which can be detrimental to their integrity and impact their cargo content. EVs are known to possess ion channels and transporters in their membrane but neither the function nor the role of these channels in EVs is known. In this study, we discover a functional calcium-activated large-conductance potassium channel (BKCa) in the membrane of EVs. Furthermore, we establish that BKCa is essential for the structural and functional integrity of EVs. Together, these findings establish the critical role of ion channels such as BKCa in functioning as gatekeepers and maintaining EV-mediated signaling.

Ischemia/reperfusion (I/R) injury is marked by the restriction and subsequent restoration of blood supply to an organ. This process can exacerbate the initial tissue damage, leading to further disorders, disability, and even death. Extracellular vesicles (EVs) are crucial in cell communication by releasing cargo that regulates the physiological state of recipient cells. The development of EVs presents a novel avenue for delivering therapeutic agents in I/R therapy. The therapeutic potential of EVs derived from stem cells, endothelial cells, and plasma in I/R injury has been actively investigated. Therefore, this review aims to provide an overview of the pathological process of I/R injury and the biophysical properties of EVs. We noted that EVs serve as nontoxic, flexible, and multifunctional carriers for delivering therapeutic agents capable of intervening in I/R injury progression. The therapeutic efficacy of EVs can be enhanced through various engineering strategies. Improving the tropism of EVs via surface modification and modulating their contents via preconditioning are widely investigated in preclinical studies. Finally, we summarize the challenges in the production and delivery of EV-based therapy in I/R injury and discuss how it can advance. This review will encourage further exploration in developing efficient EV-based delivery systems for I/R treatment.

Abdominal aortic aneurysm (AAA) rupture is a significant cause of mortality in the elderly population. Despite experimental models identifying promising pharmacological therapies, there is still a lack of pharmacological interventions for AAA prior to surgery. This study aims to evaluate the regulatory role of the novel adenosine monophosphate-activated protein kinase (AMPK) agonist O304 in AAA formation and explore its underlying molecular mechanisms.

We evaluated the expression of AMPK signaling pathway components and contractile vascular smooth muscle cell (VSMC)-related genes in AAA samples from mice using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). We evaluate the TGF-β expression by western blotting and RT-qPCR and TGF-β concentration in blood by ELISA. We developed an in vitro model of transforming growth factor-β (TGF-β)-induced VSMC phenotypic switching. After treatment with O304, we analyzed the expression of contractile genes and proteins in VSMCs by immunofluorescence and Western blotting. We also evaluated the expression of AMPK signaling pathway components and matrix metalloproteinases by western blotting and immunofluorescence analysis. We established a mouse model of AAA to evaluate the impact of O304 on aneurysm diameter and blood pressure, analyzed VSMC phenotypic switching through immunofluorescence analysis, and assessed the regulatory effects of O304 on AMPK signaling in the mouse model of AAA by Western blotting.

AMPK signaling pathway components and contractile genes in VSMCs were downregulated in mouse AAA samples, underscoring the crucial role of AMPK signaling in VSMC phenotypic switching. In the TGF-β-induced model of VSMC phenotypic switching, O304 activated AMPK signaling and prevented VSMC phenotypic switching from the contractile to the synthetic phenotype. Moreover, O304 significantly activated AMPK signaling, increased the proportion of contractile VSMCs, and reduced AAA formation and blood pressure in the mouse model of AAA.

During AAA development, VSMCs transitioned from the contractile to the proliferative phenotype, a process that has previously been associated with AMPK pathway inhibition. O304, an AMPK agonist, activated the AMPK pathway, preventing VSMC phenotypic switching and inhibiting AAA formation. These findings highlight the therapeutic potential of targeting the AMPK pathway in AAA.

Heart failure (HF) remains prevalent in patients who survived myocardial infarction (MI). Despite the accessibility of the primary percutaneous coronary intervention and medications that alleviate ventricular remodeling with functional improvement, there is an urgent need for clinicians and basic scientists to further reveal the mechanisms behind post-MI HF as well as investigate earlier and more efficient treatment after MI. Growing numbers of studies have highlighted the crucial role of macrophages in cardiac repair and remodeling following MI, and timely intervention targeting the immune response via macrophages may represent a promising therapeutic avenue. Recently, technology such as single-cell sequencing has provided us with an updated and in-depth understanding of the role of macrophages in MI. Meanwhile, the development of biomaterials has made it possible for macrophage-targeted therapy. Thus, an overall and thorough understanding of the role of macrophages in post-MI HF and the current development status of macrophage-based therapy will assist in the further study and development of macrophage-targeted treatment for post-infarction cardiac remodeling. This review synthesizes the spatiotemporal dynamics, function, mechanism and signaling of macrophages in the process of HF after MI, as well as discusses the emerging bio-materials and possible therapeutic agents targeting macrophages for post-MI HF.

Recanalization therapy can significantly improve the prognosis of patients with acute myocardial infarction (AMI). However, infarction or reperfusion-induced cardiomyocyte death, immune cell infiltration, fibroblast proliferation, and scarring formation lead to cardiac remodeling and gradually progress to heart failure or arrhythmia, resulting in a high mortality rate. Due to the inability of cardiomyocytes to regenerate, the healing of infarcted myocardium mainly relies on the formation of scars. Cardiac fibroblasts, as the main effector cells involved in repair and scar formation, play a crucial role in maintaining the structural integrity of the heart after MI. Recent studies have revealed that exosome-mediated intercellular communication plays a huge role in myocardial repair and signaling transduction after myocardial infarction (MI). Exosomes can regulate the biological behavior of fibroblasts by activating or inhibiting the intracellular signaling pathways through their contents, which are derived from cardiomyocytes, immune cells, endothelial cells, mesenchymal cells, and others. Understanding the interactions between fibroblasts and other cell types during cardiac remodeling will be the key to breakthrough therapies. This review examines the role of exosomes from different sources in the repair process after MI injury, especially the impacts on fibroblasts during myocardial remodeling, and explores the use of exosomes in the treatment of myocardial remodeling after MI.

Cell therapy can protect cardiomyocytes from hypoxia, primarily via paracrine secretions, including extracellular vesicles (EVs). Since EVs fulfil specific biological functions based on their cellular origin, we hypothesised that EVs from human cardiac stromal cells (CMSCLCs) obtained from coronary artery bypass surgery may have cardioprotective properties.

This study characterises CMSCLC EVs (C_EVs), miRNA cargo, cardioprotective efficacy and transcriptomic modulation of hypoxic human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs). C_EVs are compared to bone marrow mesenchymal stromal cell EVs (B_EVs) which are a known therapeutic EV type.

Cells were characterised for surface markers, gene expression and differentiation potential. EVs were compared for yield, phenotype, and ability to protect hiPSC-CMs from hypoxia/reoxygenation injury. EV dose was normalised by both protein concentration and particle count, allowing direct comparison. C_EV and B_EV miRNA cargo was profiled and RNA-seq was performed on EV-treated hypoxic hiPSC-CMs, then data were integrated by multi-omics. Confirmatory experiments were carried out using miRNA mimics.

At the same dose, C_EVs were more effective than B_EVs at protecting CM integrity, reducing apoptotic markers, and cell death during hypoxia. While C_EVs and B_EVs shared 70-77% similarity in miRNA content, C_EVs contained unique miRNAs, including miR-202-5p, miR-451a and miR-142-3p. Delivering miRNA mimics confirmed that miR-1260a and miR-202/451a/142 were cardioprotective, and the latter upregulated protective pathways similar to whole C_EVs.

This study demonstrates the potential of cardiac tissues, routinely discarded following surgery, as a valuable source of EVs for myocardial infarction therapy. We also identify miR-1260a as protective of CM hypoxia.

The objective of the study was to assess the therapeutic efficacy of targeting remote zone cardiomyocytes with cardiosphere-derived cell (CDC) extracellular vesicles (EVs) delivered via intramyocardial and intravenous routes following acute myocardial infarction (MI). Cardiomyocyte (CM) cell death plays a significant role in left ventricular (LV) remodeling and cardiac dysfunction following MI. While EVs secreted by CDCs have shown efficacy in promoting cardiac repair in preclinical models of MI, their translational potential is limited by their biodistribution and requirement for intramyocardial delivery. We hypothesized that engineering the surface of EVs to target cardiomyocytes would enhance their therapeutic efficacy following systemic delivery in a model of acute MI. CDC-derived EVs were engineered to express a CM-specific binding peptide (CMP) on their surface and characterized for size, morphology, and protein expression. Mice with acute MI underwent both intramyocardial and intravenous delivery of EVs, CMP-EVs and placebo in a double-blind study. LVEF was assessed by echo at 2- and 28-days post-MI and tissue samples processed for assessment of EV biodistribution and histological endpoints. CMP-EVs demonstrated superior cardiac targeting and retention when compared with unmodified EVs 24 h post-MI. Mice treated with IV delivered CMP-EVs demonstrated a significant improvement in LVEF and a significant reduction in remote zone cardiomyocyte apoptosis when compared with IV delivered non-targeted EVs at 28-day post-MI. Systemic administration of CMP-EVs improved cardiac function and reduced remote zone cardiomyocyte apoptosis compared with IV-administered unmodified EVs, demonstrating a strategy to optimize therapeutic EV delivery post-MI.

Ischemic heart disease refers to the imbalance between the supply and demand of myocardial blood; it has various causes and results in a class of clinical diseases characterized by myocardial ischemia (MI). In recent years, the incidence of cardiovascular disease has become higher and higher, and the number of patients with ischemic heart disease has also increased year by year. Traditional treatment methods include drug therapy and surgical treatment, both of which have limitations. The former maybe develop risks of drug resistance and has more significant side effects, while the latter may damage blood vessels and risk infection. At this stage, a new cell-free treatment method needs to be explored. Many research results have shown that exosomes from different cell sources can protect the ischemic myocardium via intercellular action methods, such as promoting angiogenesis, inhibiting myocardial fibrosis, apoptosis and pyroptosis, and providing a new basis for the treatment of MI. In this review, we briefly introduce the formation and consequences of myocardial ischemia and the biology of exosomes, and then focus on the role and mechanism of exosomes from different sources in MI. We also discuss the role and mechanism of exosomes pretreated with Chinese and Western medicines on myocardial ischemia. We also discuss the potential of exosomes as diagnostic markers and therapeutic drug for MI.

The delivery of therapeutic long non-coding RNAs (lncRNA) to the heart by extracellular vesicles (EVs) is promising for heart repair. H19, a lncRNA acting as a major regulator of gene expression within the cardiovascular system, is alternatively spliced, but the loading of its different splice variants into EVs and their subsequent uptake by recipient cardiac cells remain elusive. Here, we dissected the cellular expression of H19 splice variants and their loading into EVs secreted by Wharton-Jelly mesenchymal stromal/stem cells (WJ-MSCs). We demonstrated that overexpression of the mouse H19 gene in WJ-MSCs induces the expression of H19 splice variants at different levels. Interestingly, EVs isolated from the H19-transfected WJ-MSCs (EV-H19) showed similar expression levels for all tested splice variant sets. In vitro, we further demonstrated that EV-H19 was taken up by cardiomyocytes, fibroblasts, and endothelial cells (ECs). Finally, analysis of EV tropism in living rat myocardial slices indicated that EVs were internalized mostly by cardiomyocytes and ECs. Collectively, our results indicated that EVs can be loaded with different lncRNA splice variants and successfully internalized by cardiac cells.

Biobased therapy represents a promising strategy for myocardial repair. However, the limitations of using live cells, including the risk of immunogenicity of allogeneic cells and inconsistent therapeutic efficacy of autologous cells together with low stability, result in an unsatisfactory clinical outcomes. Therefore, cell-free strategies for cardiac tissue repair have been proposed as alternative strategies. Cell-free strategies, primarily based on the paracrine effects of cellular therapy, have demonstrated their potential to inhibit apoptosis, reduce inflammation, and promote on-site cell migration and proliferation, as well as angiogenesis, after an infarction and have been explored preclinically and clinically. Among various cell-free modalities, bioderived nanoparticles, including adeno-associated virus (AAV), extracellular vesicles, cell membrane-coated nanoparticles, and exosome-mimetic nanovesicles, have emerged as promising strategies due to their improved biological function and therapeutic effect. The main focus of this review is the development of existing cellular nanoparticles and their fundamental working mechanisms, as well as the challenges and opportunities. The key processes and requirements for cardiac tissue repair are summarized first. Various cellular nanoparticle modalities are further highlighted, together with their advantages and limitations. Finally, we discuss various delivery approaches that offer potential pathways for researchers and clinicians to translate cell-free strategies for cardiac tissue repair into clinical practice.

Biomaterials have potential applications in the treatment of myocardial infarction (MI). These biomaterials have the ability to mechanically support the ventricular wall and to modulate the inflammatory, metabolic, and local electrophysiological microenvironment. In addition, they can play an equally important role in promoting angiogenesis, which is the primary prerequisite for the treatment of MI. A variety of biomaterials are known to exert pro-angiogenic effects, but the pro-angiogenic mechanisms and functions of different biomaterials are complex and diverse, and have not yet been systematically described. This review will focus on the pro-angiogenesis of biomaterials and systematically describe the mechanisms and functions of different biomaterials in promoting angiogenesis in MI.

Exosome therapy shows potential for cardiac repair after injury. However, intrinsic challenges such as short half-life and lack of clear targets hinder the clinical feasibility. Here, we report a noninvasive and repeatable method for exosome delivery through inhalation after myocardial infarction (MI), which we called stem cell-derived exosome nebulization therapy (SCENT).

Stem cell-derived exosomes were characterized for size distribution and surface markers. C57BL/6 mice with MI model received exosome inhalation treatment through a nebulizer for 7 consecutive days. Echocardiographies were performed to monitor cardiac function after SCENT, and histological analysis helped with the investigation of myocardial repair. Single-cell RNA sequencing of the whole heart was performed to explore the mechanism of action by SCENT. Last, the feasibility, efficacy, and general safety of SCENT were demonstrated in a swine model of MI, facilitated by 3-dimensional cardiac magnetic resonance imaging.

Recruitment of exosomes to the ischemic heart after SCENT was detected by ex vivo IVIS imaging and fluorescence microscopy. In a mouse model of MI, SCENT ameliorated cardiac repair by improving left ventricular function, reducing fibrotic tissue, and promoting cardiomyocyte proliferation. Mechanistic studies using single-cell RNA sequencing of mouse heart after SCENT revealed a downregulation of Cd36 in endothelial cells (ECs). In an EC-Cd36fl/- conditional knockout mouse model, the inhibition of CD36, a fatty acid transporter in ECs, led to a compensatory increase in glucose utilization in the heart and higher ATP generation, which enhanced cardiac contractility. In pigs, cardiac magnetic resonance imaging showed an enhanced ejection fraction (Δ=11.66±5.12%) and fractional shortening (Δ=5.72±2.29%) at day 28 after MI by SCENT treatment compared with controls, along with reduced infarct size and thickened ventricular wall.

In both rodent and swine models, our data proved the feasibility, efficacy, and general safety of SCENT treatment against acute MI injury, laying the groundwork for clinical investigation. Moreover, the EC-Cd36fl/- mouse model provides the first in vivo evidence showing that conditional EC-CD36 knockout can ameliorate cardiac injury. Our study introduces a noninvasive treatment option for heart disease and identifies new potential therapeutic targets.

Extracellular vesicles (EVs) are involved in both physiological and pathological processes in many organ systems and are essential in mediating intercellular communication and maintaining organismal homeostasis. It is helpful to propose new strategies for disease treatment by elucidating the mechanisms of EV release and sorting. An increasing number of studies have shown that there is specific homeostasis in EVs, which is helpful for the human body to carry out physiological activities. In contrast, an EV homeostasis im-balance promotes or accelerates disease onset and development. Alternatively, regulating the quality of EVs can maintain homeostasis and even achieve the purpose of treating conditions. An analysis of the role of EV homeostasis in the onset and development of cardiovascular disease is presented in this review. This article also summarizes the methods that regulate EV homeostasis and their application in cardiovascular diseases. In particular, this study focuses on the connection between EV steady states and the cardiovascular system and the potential value of EVs in treating cardiovascular diseases.

Septic cardiomyopathy, a life-threatening complication of sepsis, can cause acute heart failure and carry a high mortality risk. Current treatments have limitations. Fortunately, engineered exosomes, created through bioengineering technology, may represent a potential new treatment method. These exosomes can both diagnose and treat septic cardiomyopathy, playing a crucial role in its development and progression. This article examines the strategies for using engineered exosomes to protect cardiac function and treat septic cardiomyopathy. It covers three innovative aspects: exosome surface modification technology, the use of exosomes as a multifunctional drug delivery platform, and plant exosome-like nanoparticle carriers. The article highlights the ability of exosomes to deliver small molecules, proteins, and drugs, summarizing several RNA molecules, proteins, and drugs beneficial for treating septic cardiomyopathy. Although engineered exosomes are a promising biotherapeutic carrier, they face challenges in clinical application, such as understanding the interaction mechanism with host cells, distribution within the body, metabolism, and long-term safety. Further research is essential, but engineered exosomes hold promise as an effective treatment for septic cardiomyopathy.

From their humble discovery as cellular debris to cementing their natural capacity to transfer functional molecules between cells, the long-winded journey of extracellular vesicles (EVs) now stands at the precipice as a next-generation cell-free therapeutic tool to revolutionize modern-day medicine. This perspective provides a snapshot of the discovery of EVs to their emergence as a vibrant field of biology and the renaissance they usher in the field of biomedical sciences as therapeutic agents for cardiovascular pathologies. Rapid development of bioengineered EVs is providing innovative opportunities to overcome biological challenges of natural EVs such as potency, cargo loading and enhanced secretion, targeting and circulation half-life, localized and sustained delivery strategies, approaches to enhance systemic circulation, uptake and lysosomal escape, and logistical hurdles encompassing scalability, cost, and time. A multidisciplinary collaboration beyond the field of biology now extends to chemistry, physics, biomaterials, and nanotechnology, allowing rapid development of designer therapeutic EVs that are now entering late-stage human clinical trials.

The specific pathophysiological pathways through which diabetes exacerbates myocardial ischemia/reperfusion (I/R) injury remain unclear; however, dysregulation of immune and inflammatory cells, potentially driven by abnormalities in their number and function due to diabetes, may play a significant role. In the present investigation, we simulated myocardial I/R injury by inducing ischemia through ligation of the left anterior descending coronary artery in mice for 40 min, followed by reperfusion for 24 h. Previous studies have indicated that protein kinase Cβ (PKCβ) is upregulated under hyperglycemic conditions and is implicated in the development of various diabetic complications. The Y4 RNA fragment is identified as the predominant small RNA component present in the extracellular vesicles of cardio sphere-derived cells (CDCs), exhibiting notable anti-inflammatory properties in the contexts of myocardial infarction and cardiac hypertrophy. Our investigation revealed that the administration of Y4 RNA into the ventricular cavity of db/db mice following myocardial I/R injury markedly enhanced cardiac function. Furthermore, Y4 RNA was observed to facilitate M2 macrophage polarization and interleukin-10 secretion through the suppression of PKCβ activation. The mechanism by which Y4 RNA affects PKCβ by regulating macrophage activation within the inflammatory environment involves the inhibition of ERK1/2 phosphorylation In our study, the role of PKCβ in regulating macrophage polarization during myocardial I/R injury was investigated through the use of PKCβ knockout mice. Our findings indicate that PKCβ plays a crucial role in modulating the inflammatory response associated with macrophage activation in db/db mice experiencing myocardial I/R, with a notable exacerbation of this response observed upon significant upregulation of PKCβ expression. In vitro studies further elucidated the protective mechanism by which Y4 RNA modulates the PKCβ/ERK1/2 signaling pathway to induce M2 macrophage activation. Overall, our findings suggest that Y4 RNA plays an anti-inflammatory role in diabetic I/R injury, suggesting a novel therapeutic approach for managing myocardial I/R injury in diabetic individuals.

Exosomes (EXOs) are a subgroup of extracellular vesicles (EVs) that contain numerous biologically active molecules. They exhibit an essential mode of cell communication, primarily between distinct cell populations, for the maintenance of tissue homeostasis and coordination of adaptive responses to various stresses. These intercellular communications are vital for the complex, multicellular cardiovascular system. In the last ten years, their potential role as effective tissue-to-tissue communicators has received increasing attention in cardiovascular physiology and pathology. There is growing evidence that repair of the heart and regeneration can be promoted by EXOs derived from cardiomyocytes or stem/progenitor cells. However, the underlying mechanisms remain unclear. EVs derived from different stem/progenitor cell populations have been used as cell-free therapies in different preclinical models involving cardiovascular diseases and have shown promising results. In this review, we have summarized the recent developments in EXOs research, the impact of EXOs derived from different cells on the cardiovascular system, their potential therapeutic roles as well as new diagnostic biomarkers, and the possible clinical translational outcomes.

Heart failure is a root cause of morbidity and mortality worldwide. Due to the limited regenerative capacity of the heart following myocardial injury, stem cell-based therapies have been considered a hopeful approach for improving cardiac regeneration. In recent years, different kinds of cell products have been investigated regarding their potential to treat patients with heart failure. Despite special attention to cell therapy and its products, therapeutic efficacy has been disappointing, and clinical application is not affordable. In the past few years, a subset of small extracellular vehicles (EVs), commonly known as "exosomes," was reported to grant regenerative and cardioprotective signals at a value similar to their donor cells. The conceptual advantage is that they may be ideally used without evoking a relevant recipient immune response or other adverse effects associated with viable cells. The evidence related to their beneficial effects in animal models of heart failure is rapidly growing. However, there is remarkable heterogeneity regarding source cells, isolation process, effective dosage, and delivery mode. This brief review will focus on the latest research and debates on regenerative potential and cardiac repair of exosomes from different sources, such as cardiac/non-cardiac stem, somatic cells, and progenitor cells. Overall, the current state of research on exosomes as an experimental therapy for heart diseases will be discussed.

Cardiovascular disease is a worldwide health problem and a leading cause of morbidity and mortality. Preclinical cardiovascular research using animals is needed to explore potential targets and therapeutic options. Compared with rodents, pigs have many advantages, with their anatomy, physiology, metabolism and immune system being more similar to humans. Here we present an overview of the available pig models for cardiovascular diseases, discuss their advantages over other models and propose the concept of standardized models to improve translation to the clinical setting and control research costs.

Ischemia-reperfusion injury (IRI) poses significant challenges across various organ systems, including the heart, brain, and kidneys. Exosomes have shown great potentials and applications in mitigating IRI-induced cell and tissue damage through modulating inflammatory responses, enhancing angiogenesis, and promoting tissue repair. Despite these advances, a more systematic understanding of exosomes from different sources and their biotransport is critical for optimizing therapeutic efficacy and accelerating the clinical adoption of exosomes for IRI therapies. Therefore, this review article overviews the administration routes of exosomes from different sources, such as mesenchymal stem cells and other somatic cells, in the context of IRI treatment. Furthermore, this article covers how the delivered exosomes modulate molecular pathways of recipient cells, aiding in the prevention of cell death and the promotions of regeneration in IRI models. In the end, this article discusses the ongoing research efforts and propose future research directions of exosome-based therapies.

Cardiac repair remains a thorny issue for survivors of acute myocardial infarction (AMI), due to the regenerative inertia of myocardial cells. Cell-free therapies, such as exosome transplantation, have become a potential strategy for myocardial injury. The aim of this study was to investigate the role of engineered exosomes in overexpressing Growth Differentiation Factor-15 (GDF-15) (GDF15-EVs) after myocardial injury, and their molecular mechanisms in cardiac repair.

H9C2 cells were transfected with GDF-15 lentivirus or negative control. The exosomes secreted from H9C2 cells were collected and identified. The cellular apoptosis and autophagy of H2O2-injured H9C2 cells were assessed by Western blotting, TUNEL assay, electron microscopy, CCK-8 and caspase 3/7 assay. A rat model of AMI was constructed by ligating the left anterior descending artery. The anti-apoptotic, pro-angiogenic effects of GDF15-EVs treatment, as well as ensuing functional and histological recovery were evaluated. Then, mRNA sequencing was performed to identify the differentially expressed mRNAs after GDF15-EVs treatment.

GDF15-EVs inhibited apoptosis and promoted autophagy in H2O2 injured H9C2 cells. GDF15-EVs effectively decreased the infarct area and enhanced the cardiac function in rats with AMI. Moreover, GDF15-EVs hindered inflammatory cell infiltration, inhibited cell apoptosis, and promoted cardiac angiogenesis in rats with AMI. RNA sequence showed that telomerase reverse transcriptase (TERT) mRNA was upregulated in GDF15-EVs-treated H9C2 cells. AMPK signaling was activated after GDF15-EVs. Silencing TERT impaired the protective effects of GDF15-EVs on H2O2-injured H9C2 cells.

GDF15-EVs could fulfil their protective effects against myocardial injury by upregulating the expression of TERT and activating the AMPK signaling pathway. GDF15-EVs might be exploited to design new therapies for AMI.

Cardiovascular diseases (CVDs) continue to be a significant global health concern. Many studies have reported promising outcomes from using MSCs and their secreted exosomes in managing various cardiovascular-related diseases like myocardial infarction (MI). MSCs and exosomes have demonstrated considerable potential in promoting regeneration and neovascularization, as well as exerting beneficial effects against apoptosis, remodeling, and inflammation in cases of myocardial infarction. Nonetheless, ensuring the durability and effectiveness of MSCs and exosomes following in vivo transplantation remains a significant concern. Recently, novel methods have emerged to improve their effectiveness and robustness, such as employing preconditioning statuses, modifying MSC and their exosomes, targeted drug delivery with exosomes, biomaterials, and combination therapy. Herein, we summarize the novel approaches that intensify the therapeutic application of MSC and their derived exosomes in treating MI.

Heart failure (HF) is an end-stage of many cardiac diseases and one of the main causes of death worldwide. The current management of this disease remains suboptimal. The adult mammalian heart was considered a post-mitotic organ. However, several reports suggest that it may possess modest regenerative potential. Adult cardiac progenitor cells (CPCs), the main players in the cardiac regeneration, constitute, as it may seem, a heterogenous group of cells, which remain quiescent in physiological conditions and become activated after an injury, contributing to cardiomyocytes renewal. They can mediate their beneficial effects through direct differentiation into cardiac cells and activation of resident stem cells but majorly do so through paracrine release of factors. CPCs can secrete cytokines, chemokines, and growth factors as well as exosomes, rich in proteins, lipids and non-coding RNAs, such as miRNAs and YRNAs, which contribute to reparation of myocardium by promoting angiogenesis, cardioprotection, cardiomyogenesis, anti-fibrotic activity, and by immune modulation. Preclinical studies assessing cardiac progenitor cells and cardiac progenitor cells-derived exosomes on damaged myocardium show that administration of cardiac progenitor cells-derived exosomes can mimic effects of cell transplantation. Exosomes may become new promising therapeutic strategy for heart regeneration nevertheless there are still several limitations as to their use in the clinic. Key questions regarding their dosage, safety, specificity, pharmacokinetics, pharmacodynamics and route of administration remain outstanding. There are still gaps in the knowledge on basic biology of exosomes and filling them will bring as closer to translation into clinic.

Cardiac disorders remain the leading cause of mortality worldwide. Current clinical strategies, including drug therapy, surgical interventions, and organ transplantation offer limited benefits to patients without regenerating the damaged myocardium. Over the past decade, stem cell therapy has generated a keen interest owing to its unique self-renewal and immune privileged characteristics. Furthermore, the ability of stem cells to differentiate into specialized cell types, has made them a popular therapeutic tool against various diseases. This comprehensive review provides an overview of therapeutic potential of different types of stem cells in reference to cardiovascular diseases. Furthermore, it sheds light on the advantages and limitations associated with each cell type. An in-depth analysis of the challenges associated with stem cell research and the hurdles for its clinical translation and their possible solutions have also been elaborated upon. It examines the controversies surrounding embryonic stem cells and the emergence of alternative approaches, such as the use of induced pluripotent stem cells for cardiac therapeutic applications. Overall, this review serves as a valuable resource for researchers, clinicians, and policymakers involved in the field of regenerative medicine, guiding the development of safe and effective stem cell-based therapies to revolutionize patient care.

Noncoding RNAs (ncRNAs) are increasingly recognized as bioactive. Here we report the development of TY1, a synthetic ncRNA bioinspired by a naturally-occurring human small Y RNA with immunomodulatory properties. TY1 upregulates TREX1, an exonuclease that rapidly degrades cytosolic DNA. In preclinical models of myocardial infarction (MI) induced by ischemia/reperfusion, TY1 reduced scar size. The cardioprotective effect of TY1 was abrogated by prior depletion of macrophages and mimicked by adoptive transfer of macrophages exposed either to TY1 or TREX1. Inhibition of TREX1 in macrophages blocked TY1 cardioprotection. Consistent with a central role for TREX1, TY1 attenuated DNA damage in the post-MI heart. This novel mechanism-pharmacologic upregulation of TREX1 in macrophages-establishes TY1 as the prototype for a new class of ncRNA drugs with disease-modifying bioactivity.

Upregulation of three prime exonuclease, TREX1, in macrophages enhances tissue repair post myocardial infarction.

Cardiovascular research has heavily relied on studies using patient samples and animal models. However, patient studies often miss the data from the crucial early stage of cardiovascular diseases, as obtaining primary tissues at this stage is impracticable. Transgenic animal models can offer some insights into disease mechanisms, although they usually do not fully recapitulate the phenotype of cardiovascular diseases and their progression. In recent years, a promising breakthrough has emerged in the form of in vitro three-dimensional (3D) cardiovascular models utilizing human pluripotent stem cells. These innovative models recreate the intricate 3D structure of the human heart and vessels within a controlled environment. This advancement is pivotal as it addresses the existing gaps in cardiovascular research, allowing scientists to study different stages of cardiovascular diseases and specific drug responses using human-origin models. In this review, we first outline various approaches employed to generate these models. We then comprehensively discuss their applications in studying cardiovascular diseases by providing insights into molecular and cellular changes associated with cardiovascular conditions. Moreover, we highlight the potential of these 3D models serving as a platform for drug testing to assess drug efficacy and safety. Despite their immense potential, challenges persist, particularly in maintaining the complex structure of 3D heart and vessel models and ensuring their function is comparable to real organs. However, overcoming these challenges could revolutionize cardiovascular research. It has the potential to offer comprehensive mechanistic insights into human-specific disease processes, ultimately expediting the development of personalized therapies.

Stem/progenitor cells have been widely evaluated as a promising therapeutic option for heart failure (HF). Numerous clinical trials with stem/progenitor cell-based therapy (SCT) for HF have demonstrated encouraging results, but not without limitations or discrepancies. Recent technological advancements in multiomics, bioinformatics, precision medicine, artificial intelligence (AI), and machine learning (ML) provide new approaches and insights for stem cell research and therapeutic development. Integration of these new technologies into stem/progenitor cell therapy for HF may help address: 1) the technical challenges to obtain reliable and high-quality therapeutic precursor cells, 2) the discrepancies between preclinical and clinical studies, and 3) the personalized selection of optimal therapeutic cell types/populations for individual patients in the context of precision medicine. This review summarizes the current status of SCT for HF in clinics and provides new perspectives on the development of computation-aided SCT in the era of precision medicine and AI/ML.

The heart rejuvenating effects of circulating growth differentiation factor 11 (GDF11), a transforming growth factor-β superfamily member that shares 90% homology with myostatin (MSTN), remains controversial. Here, we aimed to probe the role of GDF11 in acute myocardial infarction (MI), a frequent cause of heart failure and premature death during ageing.

In contrast to endogenous Mstn, myocardial Gdf11 declined during the course of ageing and was particularly reduced following ischaemia/reperfusion (I/R) injury, suggesting a therapeutic potential of GDF11 signalling in MI. Unexpectedly, boosting systemic Gdf11 by recombinant GDF11 delivery (0.1 mg/kg body weight over 30 days) prior to myocardial I/R augmented myocardial infarct size in C57BL/6 mice irrespective of their age, predominantly by accelerating pro-apoptotic signalling. While intrinsic cardioprotective signalling pathways remained unaffected by high circulating GDF11, targeted transcriptomics and immunomapping studies focusing on GDF11-associated downstream targets revealed attenuated Nkx2-5 expression confined to CD105-expressing cells, with pro-apoptotic activity, as assessed by caspase-3 levels, being particularly pronounced in adjacent cells, suggesting an indirect effect. By harnessing a highly specific and validated liquid chromatography-tandem mass spectrometry-based assay, we show that in prospectively recruited patients with MI circulating GDF11 but not MSTN levels incline with age. Moreover, GDF11 levels were particularly elevated in those at high risk for adverse outcomes following the acute event, with circulating GDF11 emerging as an independent predictor of myocardial infarct size, as estimated by standardized peak creatine kinase-MB levels.

Our data challenge the initially reported heart rejuvenating effects of circulating GDF11 and suggest that high levels of systemic GDF11 exacerbate myocardial injury in mice and humans alike. Persistently high GDF11 levels during ageing may contribute to the age-dependent loss of cardioprotective mechanisms and thus poor outcomes of elderly patients following acute MI.

Myocardial ischemia-reperfusion injury (MI/RI) constitutes a pivotal determinant impacting the long-term prognosis of individuals afflicted by ischemic cardiomyopathy subsequent to reperfusion therapy. Stem cells have garnered extensive application within the realm of MI/RI investigation, yielding tangible outcomes. Stem cell therapy encounters certain challenges in its application owing to the complexities associated with stem cell acquisition, a diminished homing rate, and a brief in vivo lifespan. Small extracellular vesicles (sEV) originating from mesenchymal stem cells (MSCs) have been demonstrated to possess the benefits of abundant availability, reduced immunogenicity, and a diminished tumorigenic incidence. They can exert their effects on damaged organs, improving injuries by transporting a lot of constituents, including proteins, RNA, lipid droplets, and more. This phenomenon has garnered substantial attention in the context of MI/RI treatment. Simultaneously, MSC-derived sEV (MSC-sEV) can exhibit enhanced therapeutic advantages through bioengineering modifications, biomaterial incorporation, and natural drug interventions. Within this discourse, we shall appraise the utilization of MSC-sEV and their derivatives in the context of MI/RI treatment, aiming to offer valuable insights for future research endeavors related to MI/RI.