Targeted delivery of therapeutic agents to the heart

Nanomedicines for cardiovascular diseases: Lessons learned and pathways forward

Cardiovascular diseases (CVDs) are vital causes of global mortality. Apart from lifestyle intervention like exercise for high-risk groups or patients at early period, various medical interventions such as percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) surgery have been clinically used to reduce progression and prevalence of CVDs. However, invasive surgery risk and severe complications still contribute to ventricular remodeling, even heart failure. Innovations in nanomedicines have fueled impressive medical advances, representing a CVD therapeutic alternative. Currently, clinical translation of nanomedicines from bench to bedside continues to suffer unpredictable biosafety and orchestrated behavior mechanism, which, if appropriately addressed, might pave the way for their clinical implementation in the future. While state-of-the-art advances in CVDs nanomedicines are widely summarized in this review, the focus lies on urgent preclinical concerns and is transitioned to the ongoing clinical trials including stem cells-based, extracellular vesicles (EV)-based, gene, and Chimeric Antigen Receptor T (CAR T) cell therapy whose clinically applicable potential in CVD therapy will hopefully provide first answers. Overall, this review aims to provide a concise but comprehensive understanding of perspectives and challenges of CVDs nanomedicines, especially from a clinical perspective.

Development of a decellularized extracellular matrix-derived wet adhesive for sustained drug delivery and enhanced wound healing

Complete tissue recovery following traumatic injury remains a major clinical challenge. While tissue adhesives show promise for managing traumatic injuries, developing materials with robust wet adhesion and high biocompatibility remains difficult. Decellularized extracellular matrix (ECM)-derived materials are widely utilized in tissue engineering due to their superior biocompatibility and bioactivity. In this study, a wet adhesive is developed by functionalizing ECM with dopamine. The resulting ECM-dopamine exhibits strong wet adhesion and excellent biocompatibility. Furthermore, ECM-dopamine can be engineered into a drug delivery platform for small agents and macromolecules. Solid lipid nanoparticles (SLNs) are incorporated into ECM-dopamine to enable sustained release of small molecules. The ECM-dopamine-SLN system ensures sustained drug release for at least one week upon adhesion to target tissues. ECM-dopamine-SLN loaded with antimicrobials accelerates wound healing and promotes angiogenesis by modulating the inflammatory response in a mouse skin excision model. Additionally, ECM-dopamine can deliver bioactive macromolecules to injured tissue. ECM-dopamine loaded with insulin-like growth factor-1 promotes skeletal muscle regeneration in a mouse volumetric muscle loss model, likely through the modulation of M2-like macrophage polarization. The dual functionality of ECM-dopamine as both a wet adhesive and a drug delivery platform offers significant potential for regenerative medicine applications.

Molecular Targeting of Intracellular Bacteria by Homotypic Recognizing Nanovesicles for Infected Pneumonia Treatment

Although extensive antibiotic regimens have been implemented to address pathogen-infected pneumonia, existing strategies are constrained in their efficacy against intracellular bacteria, a prominent contributor to antibiotic resistance. In addition, the concurrent occurrence of a cytokine storm during antibiotic therapy presents a formidable obstacle in the management of pneumonia caused by pathogens. In the present study, an infection-targeting system that leverages M2-macrophage-derived vesicles [exosomes (Exos)] as vehicles to convey antibiotics (antibiotics@Exos) was developed for effective pneumonia management. The proposed system can enable antibiotics to be specifically delivered to infected macrophages in pneumonia through homotypic recognition and was found to exhibit an exceptional intracellular bactericidal effect. Moreover, M2-type vesicles exhibit a high degree of efficiency in reprogramming inflammatory macrophages toward an anti-inflammatory phenotype. As a result, the administration of antibiotics@Exos was found to substantical decrease the level of the infiltrated inflammatory cells and alleviate the inflammatory factor storm in the lungs of acute lung injury mice. This intervention resulted in the alleviation of reactive-oxygen-species-induced damage, reduction of pulmonary edema, and successful pneumonia treatment. This bioactive vesicle delivery system effectively compensates for the limitations of traditional antibiotic therapy regimens with pluralism effects, paving a new strategy for serious infectious diseases, especially acute pneumonia treatment.

Innovative approaches to boost mesenchymal stem cells efficacy in myocardial infarction therapy

Stem cell-based therapy has emerged as a promising approach for heart repair, potentially regenerating damaged heart tissue and improving outcomes for patients with heart disease. However, the efficacy of stem cell-based therapies remains limited by several challenges, including poor cell survival, low retention rates, poor integration, and limited functional outcomes. This article reviews current enhancement strategies to optimize mesenchymal stem cell therapy for cardiac repair. Key approaches include optimizing cell delivery methods, enhancing cell engraftment, promoting cell functions through genetic and molecular modifications, enhancing the paracrine effects of stem cells, and leveraging biomaterials and tissue engineering techniques. By focusing on these enhancement techniques, the paper highlights innovative approaches that can potentially transform stem cell therapy into a more viable and effective treatment option for cardiac repair. The ongoing research and technological advancements continue to push the boundaries, hoping to make stem cell therapy a mainstream treatment for heart disease.

An Injectable Multifunctional Nanosweeper Eliminates Cardiac Mitochondrial DNA to Reduce Inflammation

Myocarditis, a leading cause of sudden cardiac death and heart transplantation, poses significant treatment challenges. The study of clinical samples from myocarditis patients reveals a correlation between the pathogenesis of myocarditis and cardiomyocyte mitochondrial DNA (mtDNA). During inflammation, the concentration of mtDNA in cardiomyocytes increases. Hence, it is hypothesized that the combined clearance of mtDNA and its downstream STING pathway can treat myocarditis. However, clearing mtDNA is problematic. An innovative mtDNA scavenger is introduced, Nanosweeper (NS), which utilizes its nanostructure to facilitate the transport of NS-mtDNA co-assemblies for degradation, achieving mtDNA clearance. The fluorescent mtDNA probe on NS, bound to functional peptides, enhances the stability of NS. NS also exhibits robust stability in human plasma with a half-life of up to 10 hours. In a murine myocarditis model, NS serves as a drug delivery vehicle, targeting the delivery of the STING pathway inhibitor C-176 to the myocardium. This approach synergistically modulates the cGAS-STING axis with NS, effectively attenuating myocarditis- associated inflammatory cascade. This evaluation of NS in porcine models corroborated its superior biosafety profile and cardiac targeting capability. This strategic approach of targeted mtDNA clearance couple with STING pathway inhibition, significantly augments therapeutic efficacy against myocarditis, outperforming the conventional drug C-176, indicating its clinical potential.

The Proteomic Landscape of the Coronary Accessible Heart Cell Surfaceome

Cell surface proteins (surfaceome) represent key signalling and interaction molecules for therapeutic targeting, biomarker profiling and cellular phenotyping in physiological and pathological states. Here, we employed coronary artery perfusion with membrane-impermeant biotin to label and capture the surface-accessible proteome in the neo-native (intact) heart. Using quantitative proteomics, we identified 701 heart cell surfaceome accessible by the coronary artery, including receptors, cell surface enzymes, adhesion and junctional molecules. This surfaceome comprises to 216 cardiac cell-specific surface proteins, including 29 proteins reported in cardiomyocytes (CXADR, CACNA1C), 12 in cardiac fibroblasts (ITGA8, COL3A1) and 63 in multiple cardiac cell types (ICAM1, SLC3A2, CDH2). Further, this surfaceome comprises to 53 proteins enriched in heart tissue compared to other tissues in humans and implicated in cardiac cell signalling networks involving cardiomyopathy (CDH2, DTNA, PTKP2, SNTA1, CAM, K2D/B), cardiac muscle contraction and development (ENG, SNTA1, SGCG, MYPN), calcium ion binding (SGCA, MASP1, THBS4, FBLN2, GSN) and cell metabolism (SDHA, NUDFS1, GYS1, ACO2, IDH2). This method offers a powerful tool for dissecting the molecular landscape of the coronary artery accessible heart cell surfaceome, its role in maintaining cardiac and vascular function, and potential molecular leads for studying cardiac cell interactions and systemic delivery to the neo-native heart.

AAV9-cBIN1 gene therapy rescues chronic heart failure due to ischemic cardiomyopathy in a canine model

BACKGROUND

Ischemic cardiomyopathy and resultant heart failure (HF) is a significant cause of morbidity and mortality worldwide. Downregulation of cardiac bridging integrator 1 (cBIN1), a membrane scaffolding protein responsible for organizing t-tubules and organizing the calcium handing apparatus, occurs in progressive HF. Therefore, gene therapy upregulating cBIN1 production may rescue failing muscle and clinical HF.

METHODS

Adult mongrel dogs underwent ligation of the left anterior descending artery and developed progressive dilated cardiomyopathy and chronic HF. When left ventricular ejection fraction (LVEF) dropped below 40%, the animals received a one-time series of endocardial injections of either of low dose gene therapy composed of either adeno-associated virus serotype 9 packaged cBIN1 (AAV9-cBIN1, n = 6) or AAV9-GFP (green fluorescent protein, n = 4). Animals were followed up to 7 weeks after therapy delivery with laboratory, echocardiography, and endocardial mapping assessment.

RESULTS

Post injection of the negative control, animals develop progressive symptomatic HF requiring early termination of all but one animal prior to the end of the study. In contrast, the AAV9-cBIN1-treated group reveals a significant improvement in LV function, with a noticeable improvement in LVEF (29 ± 3% vs. 42 ± 2%, p = 0.0095) and global longitudinal strain (-7.1 ± 0.9% vs. -12.5 ± 1.6%, p = 0.0095). Compared to the control animals, the AAV9-cBIN1-treated group displays improved T-tubule morphology, left ventricular chamber size, plasma biomarkers, and endocardial voltage, and survives the study period.

CONCLUSIONS

Chronic HF from ischemic cardiomyopathy can be successfully treated with low dose AAV9-cBIN1 gene therapy. This study indicates that myocardial specific therapy can dramatically reverse HF progression.

Intratracheal Delivery of a Phospholamban Decoy Peptide Attenuates Cardiac Damage Following Myocardial Infarction

Heart failure (HF) remains a major cause of mortality worldwide. While novel approaches, including gene and cell therapies, show promise, efficient delivery methods for such biologics to the heart are critically needed. One emerging strategy is lung-to-heart delivery using nanoparticle (NP)-encapsulated biologics. This study examines the efficiency of delivering a therapeutic peptide conjugated to a cell-penetrating peptide (CPP) to the heart via the lung-to-heart route through intratracheal (IT) injection in mice. The CPP, a tandem repeat of NP2 (dNP2) derived from the human novel LZAP-binding protein (NLBP), facilitates intracellular delivery of the therapeutic payload. The therapeutic peptide, SE, is a decoy peptide designed to inhibit protein phosphatase 1 (PP1)-mediated dephosphorylation of phospholamban (PLN). Our results demonstrated that IT injection of dNP2-SE facilitated efficient delivery to the heart, with peak accumulation at 3 h post-injection. The administration of dNP2-SE significantly ameliorated morphological and functional deterioration of the heart under myocardial infarction. At the molecular level, dNP2-SE effectively prevented PLN dephosphorylation in the heart. Immunoprecipitation experiments further revealed that dNP2-SE binds strongly to PP1 and disrupts its interaction with PLN. Collectively, our findings suggest that lung-to-heart delivery of a CPP-conjugated therapeutic peptide, dNP2-SE, represents a promising approach for the treatment of HF.

Identification of splenic IRF7 as a nanotherapy target for tele-conditioning myocardial reperfusion injury

The sequestration of nanoparticles by mononuclear phagocyte system is a challenge for the use of nanotherapy for treating cardiovascular diseases due to the conventionally perceived loss of therapeutic potency. Here, we revitalize cardiovascular nanotherapy by unlocking an alternative route in which nanomedicines are redirected to the spleen, leveraging its potential as a highly efficient and targeted site for remote conditioning, or tele-conditioning myocardial reperfusion injury. The theoretical foundation underpinning is the splenogenic nature of recruited monocytes upon myocardial reperfusion in the acute stage, which is confirmed through murine heterotopic spleen transplantation. Single-cell RNA-seq analysis identifies IRF7 as a pivotal mediator in the spleen-heart communication network that is initially induced in the spleen and orchestrates functional changes in myocardial macrophages. Spleen-related induction of IRF7 is also valid in human myocardial reperfusion scenarios. In addition, in a murine preclinical model of male mice, temporal inhibition of splenic IRF7 through the designed spleen-targeting erythrosome engineered with the targeting peptide RP182, termed as STEER nanoparticles, mitigates the acute-stage innate immune responses and improves the cardiac function in the long term. In contrast, systemic inhibition, genetic knockout of IRF7 or absolute depletion of splenic monocytes does not have therapeutic benefits, indicating the superiority of nanoparticle-based targeted treatment. These findings establish the spleen as a naturally favored site for nanoparticle-based treatments, offering promising avenues for managing myocardial reperfusion injury.

Extracellular vesicle therapeutics for cardiac repair

Extracellular vesicles (EVs) are cell-secreted heterogeneous vesicles that play crucial roles in intercellular communication and disease pathogenesis. Due to their non-tumorigenicity, low immunogenicity, and therapeutic potential, EVs are increasingly used in cardiac repair as cell-free therapy. There exist multiple steps for the design of EV therapies, and each step offers many choices to tune EV properties. Factors such as EV source, cargo, loading methods, routes of administration, surface modification, and biomaterials are comprehensively considered to achieve specific goals. PubMed and Google Scholar were searched in this review, 89 articles related to EV-based cardiac therapy over the past five years (2019 Jan - 2023 Dec) were included, and their key steps in designing EV therapies were counted and analyzed. We aim to provide a comprehensive overview that can serve as a reference guide for researchers to design EV-based cardiac therapies.

Surface receptor-targeted protein-based nanocarriers for drug delivery: advances in cancer therapy

Significant progress has been made in cancer therapy with protein-based nanocarriers targeted directly to surface receptors for drug delivery. The nanocarriers are a potentially effective solution for the potential drawbacks of traditional chemotherapy, such as lack of specificity, side effects, and development resistance. Peptides as nanocarriers have been designed based on their biocompatible, biodegradable, and versatile functions to deliver therapeutic agents into cancer cells, reduce systemic toxicity, and maximize therapy efficacy through utilizing targeted ligands such as antibodies, amino acids, vitamins, and other small molecules onto protein-based nanocarriers and thus ensuring that drugs selectively accumulate in the cancer cells instead of healthy organs/drug release at a target site without effects on normal cells, which inherently caused less systemic toxicity/off-target effect. Moreover, their intrinsic protein backbone naturally degradesin vivo, providing another level of safety over synthetic materials. Various issues like immunogenicity, mass production, and quality control must be addressed for widespread use. However, further studies are necessary to perfect protein engineering and improve drug loading, protein modification, and targeting. Thus, it can be concluded that protein-based nanocarriers targeted against the surface receptors would help achieve cancer management in a more focused manner, thus minimizing toxicity. The further development of these nanoparticles could bring a significant change in cancer treatment so that more personalized, targeted, and safe therapies would be available to all patients.

Extracellular vesicle-mediated VEGF-A mRNA delivery rescues ischaemic injury with low immunogenicity

BACKGROUND AND AIMS

Lackluster results from recently completed gene therapy clinical trials of VEGF-A delivered by viral vectors have heightened the need to develop alternative delivery strategies. This study aims to demonstrate the pre-clinical efficacy and safety of extracellular vesicles (EVs) loaded with VEGF-A mRNA for the treatment of ischaemic vascular disease.

METHODS

After encapsulation of full-length VEGF-A mRNA into fibroblast-derived EVs via cellular nanoporation (CNP), collected VEGF-A EVs were delivered into mouse models of ischaemic injury. Target tissue delivery was verified by in situ analysis of protein and gene expression. Functional rescue was confirmed by in vivo imaging and histology. The safety of single and serial delivery was demonstrated using immune-based assays.

RESULTS

VEGF-A EVs were generated with high mRNA content using a CNP methodology. VEGF-A EV administration demonstrated expression of exogenous VEGF-A mRNA by in situ RNA hybridization and elevated protein expression by western blot, microscopy, and enzyme-linked immunosorbent assay. Mice treated with human VEGF-A EVs after femoral or coronary artery ligation exhibited heightened neovascularization in ischaemic tissues with increased arterial perfusion and improvement in left ventricular function, respectively. Serial delivery of VEGF-EVs in injured skin showed improved wound healing with repeat administration. Importantly, as compared with adeno-associated viral and lipid nanoparticle VEGF-A gene therapy modalities, murine VEGF-A EV delivery did not trigger innate or adaptive immune responses at the injection site or systemically.

CONCLUSIONS

This study demonstrated that VEGF-A EV therapy offers efficient, dose-dependent VEGF-A protein formation with low immunogenicity, resulting in new vessel formation in murine models of ischaemic vascular disease.

LMNA-related cardiomyopathy: From molecular pathology to cardiac gene therapy

BACKGROUND

The genetic variants of LMNA cause an array of diseases that often affect the heart. LMNA-related cardiomyopathy exhibits high-penetrance and early-onset phenotypes that lead to late-stage heart failure or lethal arrhythmia. As a subtype of dilated cardiomyopathy and arrhythmogenic cardiomyopathy, LMNA-related cardiac dysfunction is resistant to existing cardiac therapeutic strategies, leaving a major unmet clinical need in cardiomyopathy management.

AIM OF REVIEW

Here we comprehensively summarize current knowledge about the genetic basis, disease models and pathological mechanisms of LMNA-related cardiomyopathy. Recent translational studies were highlighted to indicate new therapeutic modalities such as gene supplementation, gene silencing and genome editing therapy, which offer potential opportunities to overcome the difficulties in the development of specific drugs for this disease.

KEY SCIENTIFIC CONCEPTS OF REVIEW

LMNA-related cardiomyopathy involves many diverse disease mechanisms that preclude small-molecule drugs that target only a small fraction of the mechanisms. Agreeing to this notion, the first-in-human clinical trial for this disease recently reported futility. By contrast, gene therapy offers the new hope to directly intervene LMNA variants and demonstrates a tremendous potential for breakthrough therapy for this disease. Concepts in this review are also applicable to studies of other genetic diseases that lack effective therapeutics.

Polyphenol-Nanoengineered Monocyte Biohybrids for Targeted Cardiac Repair and Immunomodulation

Myocardial infarction is one of the leading cause of cardiovascular death worldwide. Invasive interventional procedures and medications are applied to attenuate the attacks associated with ischemic heart disease by reestablishing blood flow and restoring oxygen supply. However, the overactivation of inflammatory responses and unsatisfactory drug delivery efficiency in the infarcted regions prohibit functional improvement. Here, a nanoengineered monocyte (MO)-based biohybrid system, referred to as CTAs @MOs, for the heart-targeted delivery of combinational therapeutic agents (CTAs) containing anti-inflammatory IL-10 and cardiomyogenic miR-19a to overcome the limitation of malperfusion within the infarcted myocardium through a polyphenol-mediated interfacial assembly, is reported. Systemic administration of CTAs@MOs bypasses extensive thoracotomy and intramyocardial administration risks, leading to infarcted heart-specific accumulation and sustained release of therapeutic agents, enabling immunomodulation of the proinflammatory microenvironment and promoting cardiomyocyte proliferation in sequence. Moreover, CTAs@MOs, which serve as a cellular biohybrid-based therapy, significantly improve cardiac function as evidenced by enhanced ejection fractions, increased fractional shortening, and diminished infarct sizes. This polyphenol nanoengineered biohybrid system represents a general and potent platform for the efficient treatment of cardiovascular disorders.

Non-coding RNAs to treat vascular smooth muscle cell dysfunction

Vascular smooth muscle cell (vSMC) dysfunction is a critical contributor to cardiovascular diseases, including atherosclerosis, restenosis and vein graft failure. Recent advances have unveiled a fascinating range of non-coding RNAs (ncRNAs) that play a pivotal role in regulating vSMC function. This review aims to provide an in-depth analysis of the mechanisms underlying vSMC dysfunction and the therapeutic potential of various ncRNAs in mitigating this dysfunction, either preventing or reversing it. We explore the intricate interplay of microRNAs, long-non-coding RNAs and circular RNAs, shedding light on their roles in regulating key signalling pathways associated with vSMC dysfunction. We also discuss the prospects and challenges associated with developing ncRNA-based therapies for this prevalent type of cardiovascular pathology. LINKED ARTICLES: This article is part of a themed issue Non-coding RNA Therapeutics. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v182.2/issuetoc.

Lysosome-Mitochondria Cascade Targeting Nanoparticle Drives Robust Pyroptosis for Cancer Immunotherapy

The subcellular distribution of cargoes plays a crucial role in determining cell fate and therapeutic efficacy. However, achieving the precise delivery of therapeutics to specific intracellular targets remains a significant challenge. Here, we present a trimodular and acid/enzyme-gated nanoplatform (TAEN) that undergoes disassembly within acidic endosomes and then is cleaved by lysosomal cathepsin B to facilitate efficient and targeted transport of released cargoes into mitochondria compartments. By utilizing this nanovehicle, we successfully achieve selective sorting of photosensitizer molecules into mitochondria with a colocalization coefficient of up to 0.98, leading to the generation of reactive oxygen species stress specifically within the mitochondria for potent pyroptosis-based cancer therapy. The induction of mitochondrial stress triggers the intrinsic apoptotic pathway as well as caspase-3/gasdermin-E (GSDME) cascade, resulting in an enhanced cancer cell killing efficacy by nearly 2 orders of magnitude as compared to lysosomal stress. Furthermore, due to its superior capability to stimulate both innate and adaptive immune responses, our mitochondria-sorted nanophotosensitizer exhibits robust antitumor immune efficacy in multiple tumor-bearing mice models. This study not only provides insights into engineering nanomedicines for subcellular targeted delivery but also offers a valuable toolkit for advanced research in the field of nanobiology at subcellular resolution.

Intracellular delivery of a phospholamban-targeting aptamer using cardiomyocyte-internalizing aptamers

The sarco (endo)plasmic reticulum Ca2+-ATPase 2a (SERCA2a)-phospholamban (PLN) system within the sarcoplasmic reticulum is crucial for regulating intracellular Ca2+ cycling in ventricular cardiomyocytes. Given that impaired Ca2+ cycling is associated with heart failure, modulating SERCA2a activity represents a promising therapeutic strategy. Previously, we engineered an RNA aptamer (Apt30) that binds to PLN, thereby activating SERCA2a by alleviating PLN's inhibitory effect. However, Apt30 alone cannot reach intracellular PLN, necessitating the development of a mechanism for its specific internalization into cardiomyocytes. Using the systematic evolution of ligands by exponential enrichment (SELEX) method, we isolated RNA aptamers capable of internalizing into cardiomyocytes. These aptamers demonstrated sub-micromolar EC50 values for cardiomyocyte internalization and exhibited significantly reduced activity against various non-myocardial cells, highlighting their specificity for cardiomyocytes. Moreover, some of these cardiomyocyte-internalizing aptamers could be linked to Apt30 as a single RNA strand without compromising their internalization efficacy. Supplementing the culture medium with these hybrid aptamers enhanced Ca2+ transients and contractile function in rat cardiomyocytes. These findings provide critical insights for developing novel therapeutics directly acting on PLN in cardiomyocytes, potentially compensating for the disadvantages of conventional methods that involve viral vector-mediated intracellular transduction or alterations in endogenous protein expression.

Cardiac bridging integrator 1 gene therapy rescues chronic non-ischemic heart failure in minipigs

Heart failure (HF) is a major cause of mortality and morbidity worldwide, yet with limited therapeutic options. Cardiac bridging integrator 1 (cBIN1), a cardiomyocyte transverse-tubule (t-tubule) scaffolding protein which organizes the calcium handling machinery, is transcriptionally reduced in HF and can be recovered for functional rescue in mice. Here we report that in human patients with HF with reduced ejection fraction (HFrEF), left ventricular cBIN1 levels linearly correlate with organ-level ventricular remodeling such as diastolic diameter. Using a minipig model of right ventricular tachypacing-induced non-ischemic dilated cardiomyopathy and chronic HFrEF, we identified that a single intravenous low dose (6 × 1011 vg/kg) of adeno associated virus 9 (AAV9)-packaged cBIN1 improves ventricular remodeling and performance, reduces pulmonary and systemic fluid retention, and increases survival in HFrEF minipigs. In cardiomyocytes, AAV9-cBIN1 restores t-tubule organization and ultrastructure in failing cardiomyocytes. In conclusion, AAV9-based cBIN1 gene therapy rescues non-ischemic HFrEF with reduced mortality in minipigs.

T Lymphocyte-Macrophage Hybrid Membrane-Coated Biomimetic Nanoparticles Alleviate Myocarditis via Suppressing Pyroptosis by Targeting Gene Silencing

Introduction

Nanomedicine coated with cell membranes has attracted increasing attention for its enhanced targeting capability and biocompatibility. Based on previous research, we identified interferon regulatory factor 1 (IRF1)-mediated macrophage pyroptosis as a potential therapeutic target for myocarditis. Herein, we fabricated an innovative immune cell membrane-coated zeolitic imidazolate framework-8 (ZIF-8) nano-delivery platform and explored its effects on myocarditis.

Methods

ZIF-8 nanoparticles loaded with siRNA targeting IRF1 (siIRF1) were coated with a T lymphocyte-macrophage hybrid membrane (siIRF1@ZIF@HM NPs) via sonication and extrusion. The morphological and biological characteristics of the nanoparticles were evaluated using transmission electron microscopy (TEM) and dynamic light scattering (DLS). Cellular cytotoxicity was assessed by a cell counting kit-8 assay. Cellular uptake and endo-lysosomal escape in M1-differentiated macrophages were visualized via fluorescence microscopy. The targeting specificity and anti-myocarditis effects were evaluated in an experimental autoimmune myocarditis (EAM) mouse model. The anti-pyroptosis effects were assessed by Western blot analysis both in vivo and in vitro.

Results

Transcriptional sequencing identified T lymphocytes and macrophages as suitable membrane sources. The ZIF-8 nanoparticles exhibited high siRNA loading capacity and pH responsiveness, enabling an efficient release of siIRF1 from endo-lysosomes to the cytoplasm in macrophages. The hybrid membrane coating enabled specific targeting of M1 macrophages both in vivo and in vitro. Furthermore, delivery of siIRF1 effectively suppressed IRF1 expression and inhibited pyroptosis in IFN-γ-stimulated macrophages. Intravenous injection of siIRF1@ZIF@HM NPs significantly alleviated myocarditis progression without evident side effects.

Conclusion

The siIRF1 nanotherapeutic approach shows potential for attenuating myocardial inflammation and mitigating myocarditis progression. Our study highlights the promise of this customized biomimetic nano-delivery system for treating inflammatory diseases.

Gene therapy for atrial fibrillation

Atrial fibrillation (AF) is the most common sustained arrhythmia in adults. Current limitations of pharmacological and ablative therapies motivate the development of novel therapies as next generation treatments for AF. The arrhythmia mechanisms creating and sustaining AF are key elements in the development of this novel treatment. Gene therapy provides a useful platform that allows us to regulate the mechanisms of interest using a suitable transgene(s), vector, and delivery method. Effective gene therapy strategies in the literature have targeted maladaptive electrical or structural remodeling that increase vulnerability to AF. In this review, we will summarize key elements of gene therapy for AF, including molecular targets, gene transfer vectors, atrial gene delivery and preclinical efficacy and toxicity testing. Recent advances and challenges in the field will be also discussed.

Biomimetic Nanoparticles for Basic Drug Delivery

Biomimetic nanoparticles (BMNPs) are innovative nanovehicles that replicate the properties of naturally occurring extracellular vesicles, facilitating highly efficient drug delivery across biological barriers to target organs and tissues while ensuring maximal biocompatibility and minimal-to-no toxicity. BMNPs can be utilized for the delivery of therapeutic payloads and for imparting novel properties to other nanotechnologies based on organic and inorganic materials. The application of specifically modified biological membranes for coating organic and inorganic nanoparticles has the potential to enhance their therapeutic efficacy and biocompatibility, presenting a promising pathway for the advancement of drug delivery technologies. This manuscript is grounded in the fundamentals of biomimetic technologies, offering a comprehensive overview and analytical perspective on the preparation and functionalization of BMNPs, which include cell membrane-coated nanoparticles (CMCNPs), artificial cell-derived vesicles (ACDVs), and fully synthetic vesicles (fSVs). This review examines both "top-down" and "bottom-up" approaches for nanoparticle preparation, with a particular focus on techniques such as cell membrane coating, cargo loading, and microfluidic fabrication. Additionally, it addresses the technological challenges and potential solutions associated with the large-scale production and clinical application of BMNPs and related technologies.

Bioderived Nanoparticles for Cardiac Repair

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.

Fillable Magnetic Microrobots for Drug Delivery to Cardiac Tissues In Vitro

Many cardiac diseases, such as arrhythmia or cardiogenic shock, cause irregular beating patterns that must be regulated to prevent disease progression toward heart failure. Treatments can include invasive surgery or high systemic drug dosages, which lack precision, localization, and control. Drug delivery systems (DDSs) that can deliver cargo to the cardiac injury site could address these unmet clinical challenges. Here, a microrobotic DDS that can be mobilized to specific sites via magnetic control is presented. This DDS incorporates an internal chamber that can protect drug cargo. Furthermore, the DDS contains a tunable thermosensitive sealing layer that gradually degrades upon exposure to body temperature, enabling prolonged drug release. Once loaded with the small molecule drug norepinephrine, this microrobotic DDS modulated beating frequency in induced pluripotent stem-cell derived cardiomyocytes (iPSC-CMs) in a dose-dependent manner, thus simulating drug delivery to cardiac cells in vitro. The DDS also navigates several maze-like structures seeded with cardiomyocytes to demonstrate precise locomotion under a rotating low-intensity magnetic field and on-site drug delivery. This work demonstrates the utility of a magnetically actuating DDS for precise, localized, and controlled drug delivery which is of interest for a myriad of future opportunities such as in treating cardiac diseases.

Identification of In Vivo Internalizing Cardiac-Specific RNA Aptamers

Background

The pursuit of selective therapeutic delivery to target tissue types represents a key goal in the treatment of a range of adverse health issues, including diseases afflicting the heart. The development of new cardiac-specific ligands is a crucial step towards effectively targeting therapeutics to the heart.

Methods

Utilizing an ex vivo and in vivo SELEX approaches, we enriched a library of 2'-fluoro modified aptamers for ventricular cardiomyocyte specificity. Lead candidates were identified from this library, and their binding and internalization into cardiomyocytes was evaluated in both ex vivo and in vivo mouse studies.

Results

The ex vivo and in vivo SELEX processes generated an aptamer library with significant cardiac specificity over non-cardiac tissues such as liver and skeletal muscle. Our lead candidate aptamer from this library, CA1, demonstrates selective in vivo targeting and delivery of a fluorophore cargo to ventricular cardiomyocytes within the murine heart, while minimizing off-target localization to non-cardiac tissues, including the liver. By employing a novel RNase-based assay to evaluate aptamer interactions with cardiomyocytes, we discovered that CA1 predominantly internalizes into ventricular cardiomyocytes; conversely, another candidate CA41 primarily binds to the cardiomyocyte cell surface.

Conclusions

These findings suggest that CA1 and CA41 have the potential to be promising candidates for targeted drug delivery and imaging applications in cardiac diseases.

CircRNA as an Achilles heel of cancer: characterization, biomarker and therapeutic modalities

Circular RNAs (circRNAs) are a class of endogenous noncoding RNAs characterized by their lack of 5' caps and 3' poly(A) tails. These molecules have garnered substantial attention from the scientific community. A wide range of circRNA types has been found to be expressed in various tissues of the human body, exhibiting unique characteristics such as high abundance, remarkable stability, and tissue-specific expression patterns. These attributes, along with their detectability in liquid biopsy samples such as plasma, position circRNAs an ideal choice as cancer diagnostic and prognostic biomarkers. Additionally, several studies have reported that the functions of circRNAs are associated with tumor proliferation, metastasis, and drug resistance. They achieve this through various mechanisms, including modulation of parental gene expression, regulation of gene transcription, acting as microRNA (miRNA) sponges, and encoding functional proteins. In recent years, a large number of studies have focused on synthesizing circRNAs in vitro and delivering them to tumor tissue to exert its effects in inhibit tumor progression. Herein, we briefly discuss the biogenesis, characteristics, functions, and detection of circRNAs, emphasizing their clinical potential as biomarkers for cancer diagnosis and prognosis. We also provide an overview the recent techniques for synthesizing circRNAs and delivery strategies, and outline the application of engineered circRNAs in clinical cancer therapy.

Navigating cancer therapy induced cardiotoxicity: From pathophysiology to treatment innovations

Every year, more than a million people in the United States undergo chemotherapy or radiation therapy for cancer, as estimated by the CDC. While chemotherapy has been an instrumental tool for treating cancer, it also causes severe adverse effects. The more commonly acknowledged adverse effects include hair loss, fatigue, and nausea, but a more severe and longer lasting side effect is cardiotoxicity. Cardiotoxicity, or heart damage, is a common complication of cancer treatments. It can range from mild to severe, and it can affect some patients temporarily or others permanently, even after they are cured of cancer. Dexrazoxane is the only FDA-approved drug for treating anthracycline induced cardiotoxicity, but it also has drawbacks and adverse effects. There is no other type of chemotherapy induced cardiotoxicity that has an approved treatment option. In this review, we discuss the pathophysiology of chemotherapeutic-induced cardiotoxicity, methods and guidelines of diagnosis, methods of treatment and mitigation, and current drug delivery approaches in therapeutic development.

Inhalable cardiac targeting peptide modified nanomedicine prevents pressure overload heart failure in male mice

Heart failure causes considerable morbidity and mortality worldwide. Clinically applied drugs for the treatment of heart failure are still severely limited by poor delivery efficiency to the heart and off-target consumption. Inspired by the high heart delivery efficiency of inhaled drugs, we present an inhalable cardiac-targeting peptide (CTP)-modified calcium phosphate (CaP) nanoparticle for the delivery of TP-10, a selective inhibitor of PDE10A. The CTP modification significantly promotes cardiomyocyte and fibroblast targeting during the pathological state of heart failure in male mice. TP-10 is subsequently released from TP-10@CaP-CTP and effectively attenuates cardiac remodelling and improved cardiac function. In view of these results, a low dosage (2.5 mg/kg/2 days) of inhaled medication exerted good therapeutic effects without causing severe lung injury after long-term treatment. In addition, the mechanism underlying the amelioration of heart failure is investigated, and the results reveal that the therapeutic effects of this system on cardiomyocytes and cardiac fibroblasts are mainly mediated through the cAMP/AMPK and cGMP/PKG signalling pathways. By demonstrating the targeting capacity of CTP and verifying the biosafety of inhalable CaP nanoparticles in the lung, this work provides a perspective for exploring myocardium-targeted therapy and presents a promising clinical strategy for the long-term management of heart failure.

The Discovery of Extracellular Vesicles and Their Emergence as a Next-Generation Therapy

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.

RNA-binding proteins in cardiovascular biology and disease: the beat goes on

Cardiac development and function are becoming increasingly well understood from different angles, including signalling, transcriptional and epigenetic mechanisms. By contrast, the importance of the post-transcriptional landscape of cardiac biology largely remains to be uncovered, building on the foundation of a few existing paradigms. The discovery during the past decade of hundreds of additional RNA-binding proteins in mammalian cells and organs, including the heart, is expected to accelerate progress and has raised intriguing possibilities for better understanding the intricacies of cardiac development, metabolism and adaptive alterations. In this Review, we discuss the progress and new concepts on RNA-binding proteins and RNA biology and appraise them in the context of common cardiovascular clinical conditions, from cell and organ-wide perspectives. We also discuss how a better understanding of cardiac RNA-binding proteins can fill crucial knowledge gaps in cardiology and might pave the way to developing better treatments to reduce cardiovascular morbidity and mortality.

Small extracellular vesicle-mediated CRISPR-Cas9 RNP delivery for cardiac-specific genome editing

Myocardial infarction (MI) is a major cause of morbidity and mortality worldwide. Although clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (Cas9) gene editing holds immense potential for genetic manipulation, its clinical application is hindered by the absence of an efficient heart-targeted drug delivery system. Herein, we developed CRISPR-Cas9 ribonucleoprotein (RNP)-loaded extracellular vesicles (EVs) conjugated with cardiac-targeting peptide (T) for precise cardiac-specific genome editing. RNP complexes containing Cas9 and single guide RNA targeting miR-34a, an MI-associated molecular target, were loaded into EVs (EV@RNP). Gene editing by EV@RNP attenuated hydrogen peroxide-induced apoptosis in cardiomyocytes via miR-34a inhibition, evidenced by increased B-cell lymphoma 2 levels, decreased Bcl-2-associated X protein levels, and the cleavage of caspase-3. Additionally, to improve cardiac targeting in vivo, we used click chemistry to form functional T-EV@RNP by conjugating T peptides to EV@RNP. Consequently, T-EV@RNP-mediated miR-34a genome editing might exert a protective effect against MI, reducing apoptosis, ameliorating MI injury, and facilitating the recovery of cardiac function. In conclusion, the genome editing delivery system established by loading CRISPR/Cas9 RNP with cardiac-targeting EVs is a powerful approach for precise and tissue-specific gene therapy for cardiovascular disease.

Investigating Novel Therapeutic Approaches for Idiopathic Short Stature: Targeting siRNA and Growth Hormone Delivery to the Growth Plate Using Exosome Nanoparticles

Idiopathic short stature (ISS) is a common childhood condition with largely unknown underlying causes. Recent research highlights the role of circulating exosomes in the pathogenesis of various disorders, but their connection to ISS remains unexplored. In the experiments, human chondrocytes are cocultured with plasma exosomes from ISS patients, leading to impaired chondrocyte growth and bone formation. Elevated levels of a specific long non-coding RNA (lncRNA), ISSRL, are identified as a distinguishing factor in ISS, boasting high specificity and sensitivity. Silencing ISSRL in ISS plasma exosomes reverses the inhibition of chondrocyte proliferation and bone formation. Conversely, overexpression of ISSRL in chondrocytes impedes their growth and bone formation, revealing its mechanism of action through the miR-877-3p/GZMB axis. Subsequently, exosomes (CT-Exo-siISSRL-oeGH) with precise cartilage-targeting abilities are engineered, loaded with customized siRNA for ISSRL and growth hormone. This innovative approach offers a therapeutic strategy to address ISS by rectifying abnormal non-coding RNA expression in growth plate cartilage and delivering growth hormone with precision to promote bone growth. This research provides valuable insights into ISS diagnosis and treatment, highlighting the potential of engineered exosomes.

Injury minimization after myocardial infarction: focus on extracellular vesicles

Despite improvements in clinical outcomes following acute myocardial infarction, mortality remains high, especially in patients with severely reduced left ventricular ejection fraction (LVEF <30%), emphasizing the need for effective cardioprotective strategies adjunctive to recanalization. Traditional cell therapy has shown equivocal success, shifting the focus to innovative cardioactive biologicals and cell mimetic therapies, particularly extracellular vesicles (EVs). EVs, as carriers of non-coding RNAs and other essential biomolecules, influence neighbouring and remote cell function in a paracrine manner. Compared to cell therapy, EVs possess several clinically advantageous traits, including stability, ease of storage (enabling off-the-shelf clinical readiness), and decreased immunogenicity. Allogeneic EVs from mesenchymal and/or cardiac stromal progenitor cells demonstrate safety and potential efficacy in preclinical settings. This review delves into the translational potential of EV-based therapeutic approaches, specifically highlighting findings from large-animal studies, and offers a synopsis of ongoing early-stage clinical trials in this domain.

Navigating the landscape of RNA delivery systems in cardiovascular disease therapeutics

Cardiovascular diseases (CVDs) stand as the leading cause of death worldwide, posing a significant global health challenge. Consequently, the development of innovative therapeutic strategies to enhance CVDs treatment is imperative. RNA-based therapies, encompassing non-coding RNAs, mRNA, aptamers, and CRISPR/Cas9 technology, have emerged as promising tools for addressing CVDs. However, inherent challenges associated with RNA, such as poor cellular uptake, susceptibility to RNase degradation, and capture by the reticuloendothelial system, underscore the necessity of combining these therapies with effective drug delivery systems. Various non-viral delivery systems, including extracellular vesicles, lipid-based carriers, polymeric and inorganic nanoparticles, as well as hydrogels, have shown promise in enhancing the efficacy of RNA therapeutics. In this review, we offer an overview of the most relevant RNA-based therapeutic strategies explored for addressing CVDs and emphasize the pivotal role of delivery systems in augmenting their effectiveness. Additionally, we discuss the current status of these therapies and the challenges that hinder their clinical translation.

Delivery-mediated exosomal therapeutics in ischemia-reperfusion injury: advances, mechanisms, and future directions

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.

Divergent cardiac and renal effects of miR-181c-5p inhibition in a rodent heart failure model

Aims

MiR-181c-5p overexpression associates with heart failure (HF) and cardiac damage, but the underlying pathophysiology remains unclear. This study investigated the effect of miR-181c-5p inhibition on cardiac function and fibrosis in a rodent model of diastolic dysfunction, and evaluated additional effects on kidney as relevant comorbid organ.

Methods and results

Diastolic dysfunction was induced in male C57/BL6J mice (n = 20) by combining high-fat diet, L-NG-nitroarginine methyl ester, and angiotensin II administration, and was compared to sham controls (n = 18). Mice were randomized to subcutaneous miR-181c-5p antagomiR (INH) or scrambled antagomiR injections (40 mg/kg/week). HF mice demonstrated diastolic dysfunction and increased fibrosis, which was attenuated by INH treatment. Remarkably, HF + INH animals had a threefold higher mortality rate (60%) compared to HF controls (20%). Histological examination revealed increased glomerular damage in all INH treated mice, and signs of thrombotic microangiopathy (TMA) in mice who died prematurely. Quantitative polymerase chain reaction demonstrated a miR-181c-5p-related downregulation of cardiac but not renal Tgfbr1 in HF + INH mice, while INH treatment reduced renal but not cardiac Vegfa expression in all mice.

Conclusion

This study demonstrates cardiac anti-fibrotic effects of miR-181c-5p inhibition in a rodent HF model through targeting of Tgfbr1 in the heart. Despite improved diastolic function, HF + INH mice had higher mortality due to increased predisposition for TMA, increased renal fibrosis and glomerular damage, associated with Vegfa downregulation in kidneys.

Folate-conjugated organic CO prodrugs: Synthesis and CO release kinetic studies

Carbon monoxide (CO) is an endogenous produced molecule and has shown efficacy in animal models of inflammation, organ injury, colitis and cancer metastasis. Because of its gaseous nature, there is a need for developing efficient CO delivery approaches, especially those capable of targeted delivery. In this study, we aim to take advantage of a previously reported approach of enrichment-triggered prodrug activation to achieve targeted delivery by targeting the folate receptor. The general idea is to exploit folate receptor-mediated enrichment as a way to accelerate a biomolecular Diels-Alder reaction for prodrug activation. In doing so, we first need to find ways to tune the reaction kinetics in order to ensure minimal rection without enrichment and optimal activation upon enrichment. In this feasibility study, we synthesized two diene-dienophile pairs and studied their reaction kinetics and ability to target the folate receptor. We found that folate conjugation significantly affects the reaction kinetics of the original diene-dienophile pairs. Such information will be very useful in future designs of similar targeted approaches of CO delivery.

State of Gene Therapy for Monogenic Cardiovascular Diseases

Over the past 2 decades, significant efforts have been made to advance gene therapy into clinical practice. Although successful examples exist in other fields, gene therapy for the treatment of monogenic cardiovascular diseases lags behind. In this review, we (1) highlight a brief history of gene therapy, (2) distinguish between gene silencing, gene replacement, and gene editing technologies, (3) discuss vector modalities used in the field with a special focus on adeno-associated viruses, (4) provide examples of gene therapy approaches in cardiomyopathies, channelopathies, and familial hypercholesterolemia, and (5) present current challenges and limitations in the gene therapy field.

Role of long noncoding RNAs in pathological cardiac remodeling after myocardial infarction: An emerging insight into molecular mechanisms and therapeutic potential

Myocardial infarction (MI) is the leading cause of heart failure (HF), accounting for high mortality and morbidity worldwide. As a consequence of ischemia/reperfusion injury during MI, multiple cellular processes such as oxidative stress-induced damage, cardiomyocyte death, and inflammatory responses occur. In the next stage, the proliferation and activation of cardiac fibroblasts results in myocardial fibrosis and HF progression. Therefore, developing a novel therapeutic strategy is urgently warranted to restrict the progression of pathological cardiac remodeling. Recently, targeting long non-coding RNAs (lncRNAs) provided a novel insight into treating several disorders. In this regard, numerous investigations have indicated that several lncRNAs could participate in the pathogenesis of MI-induced cardiac remodeling, suggesting their potential therapeutic applications. In this review, we summarized lncRNAs displayed in the pathophysiology of cardiac remodeling after MI, emphasizing molecular mechanisms. Also, we highlighted the possible translational role of lncRNAs as therapeutic targets for this condition and discussed the potential role of exosomes in delivering the lncRNAs involved in post-MI cardiac remodeling.

Applications of Gene Therapy in Cardiomyopathies

Gene therapy is defined by the introduction of new genes or the genetic modification of existing genes and/or their regulatory portions via gene replacement and gene editing strategies, respectively. The genetic material is usually delivered though cardiotropic vectors such as adeno-associated virus 9 or engineered capsids. The enthusiasm for gene therapy has been hampered somewhat by adverse events observed in clinical trials, including dose-dependent immunologic reactions such as hepatotoxicity, acquired hemolytic uremic syndrome and myocarditis. Notably, gene therapy for Duchenne muscular dystrophy has recently been approved and pivotal clinical trials are testing gene therapy approaches in rare myocardial conditions such as Danon disease and Fabry disease. Furthermore, promising results have been shown in animal models of gene therapy in hypertrophic cardiomyopathy and arrhythmogenic cardiomyopathy. This review summarizes the gene therapy techniques, the toxicity risk associated with adeno-associated virus delivery, the ongoing clinical trials, and future targets.

Cell-Specific mRNA Therapeutics for Cardiovascular Diseases and Regeneration

Cardiovascular diseases (CVDs) represent a significant global health burden, demanding innovative therapeutic approaches. In recent years, mRNA therapeutics have emerged as a promising strategy to combat CVDs effectively. Unlike conventional small-molecule drugs, mRNA therapeutics enable the direct modulation of cellular functions by delivering specific mRNA molecules to target cells. This approach offers unprecedented advantages, including the ability to harness endogenous cellular machinery for protein synthesis, thus allowing precise control over gene expression without insertion into the genome. This review summarizes the current status of the potential of cell-specific mRNA therapeutics in the context of cardiovascular diseases. First, it outlines the challenges associated with traditional CVD treatments and emphasizes the need for targeted therapies. Subsequently, it elucidates the underlying principles of mRNA therapeutics and the development of advanced delivery systems to ensure cell-specificity and enhanced efficacy. Notably, innovative delivery methods such as lipid nanoparticles and exosomes have shown promise in improving the targeted delivery of mRNA to cardiac cells, activated fibroblasts, and other relevant cell types. Furthermore, the review highlights the diverse applications of cell-specific mRNA therapeutics in addressing various aspects of cardiovascular diseases, including atherosclerosis, myocardial infarction, heart failure, and arrhythmias. By modulating key regulatory genes involved in cardiomyocyte proliferation, inflammation, angiogenesis, tissue repair, and cell survival, mRNA therapeutics hold the potential to intervene at multiple stages of CVD pathogenesis. Despite its immense potential, this abstract acknowledges the challenges in translating cell-specific mRNA therapeutics from preclinical studies to clinical applications like off-target effects and delivery. In conclusion, cell-specific mRNA therapeutics have emerged as a revolutionary gene therapy approach for CVD, offering targeted interventions with the potential to significantly improve patient outcomes.

Advances in RNA therapeutics for modulation of 'undruggable' targets

Over the past decades, drug discovery utilizing small pharmacological compounds, fragment-based therapeutics, and antibody therapy have significantly advanced treatment options for many human diseases. However, a major bottleneck has been that>70% of human proteins/genomic regions are 'undruggable' by the above-mentioned approaches. Many of these proteins constitute essential drug targets against complex multifactorial diseases like cancer, immunological disorders, and neurological diseases. Therefore, alternative approaches are required to target these proteins or genomic regions in human cells. RNA therapeutics is a promising approach for many of the traditionally 'undruggable' targets by utilizing methods such as antisense oligonucleotides, RNA interference, CRISPR/Cas-based genome editing, aptamers, and the development of mRNA therapeutics. In the following chapter, we will put emphasis on recent advancements utilizing these approaches against challenging drug targets, such as intranuclear proteins, intrinsically disordered proteins, untranslated genomic regions, and targets expressed in inaccessible tissues.

Lung-to-Heart Nano-in-Micro Peptide Promotes Cardiac Recovery in a Pig Model of Chronic Heart Failure

BACKGROUND

The lack of disease-modifying drugs is one of the major unmet needs in patients with heart failure (HF). Peptides are highly selective molecules with the potential to act directly on cardiomyocytes. However, a strategy for effective delivery of therapeutics to the heart is lacking.

OBJECTIVES

In this study, the authors sought to assess tolerability and efficacy of an inhalable lung-to-heart nano-in-micro technology (LungToHeartNIM) for cardiac-specific targeting of a mimetic peptide (MP), a first-in-class for modulating impaired L-type calcium channel (LTCC) trafficking, in a clinically relevant porcine model of HF.

METHODS

Heart failure with reduced ejection fraction (HFrEF) was induced in Göttingen minipigs by means of tachypacing over 6 weeks. In a setting of overt HFrEF (left ventricular ejection fraction [LVEF] 30% ± 8%), animals were randomized and treatment was started after 4 weeks of tachypacing. HFrEF animals inhaled either a dry powder composed of mannitol-based microparticles embedding biocompatible MP-loaded calcium phosphate nanoparticles (dpCaP-MP) or the LungToHeartNIM only (dpCaP without MP). Efficacy was evaluated with the use of echocardiography, invasive hemodynamics, and biomarker assessment.

RESULTS

DpCaP-MP inhalation restored systolic function, as shown by an absolute LVEF increase over the treatment period of 17% ± 6%, while reversing cardiac remodeling and reducing pulmonary congestion. The effect was recapitulated ex vivo in cardiac myofibrils from treated HF animals. The treatment was well tolerated, and no adverse events occurred.

CONCLUSIONS

The overall tolerability of LungToHeartNIM along with the beneficial effects of the LTCC modulator point toward a game-changing treatment for HFrEF patients, also demonstrating the effective delivery of a therapeutic peptide to the diseased heart.

An Intrinsically Magnetic Epicardial Patch for Rapid Vascular Reconstruction and Drug Delivery

Myocardial infarction (MI) is a major cause of mortality worldwide. The major limitation of regenerative therapy for MI is poor cardiac retention of therapeutics, which results from an inefficient vascular network and poor targeting ability. In this study, a two-layer intrinsically magnetic epicardial patch (MagPatch) prepared by 3D printing with biocompatible materials like poly (glycerol sebacate) (PGS) is designed, poly (ε-caprolactone) (PCL), and NdFeB. The two-layer structure ensured that the MagPatch multifariously utilized the magnetic force for rapid vascular reconstruction and targeted drug delivery. MagPatch accumulates superparamagnetic iron oxide (SPION)-labelled endothelial cells, instantly forming a ready-implanted organization, and rapidly reconstructs a vascular network anastomosed with the host. In addition, the prefabricated vascular network within the MagPatch allowed for the efficient accumulation of SPION-labelled therapeutics, amplifying the therapeutic effects of cardiac repair. This study defined an extendable therapeutic platform for vascularization-based targeted drug delivery that is expected to assist in the progress of regenerative therapies in clinical applications.

Extracellular vesicles modulate key signalling pathways in refractory wound healing

Chronic wounds are wounds that cannot heal properly due to various factors, such as underlying diseases, infection or reinjury, and improper healing of skin wounds and ulcers can cause a serious economic burden. Numerous studies have shown that extracellular vesicles (EVs) derived from stem/progenitor cells promote wound healing, reduce scar formation and have significant advantages over traditional treatment methods. EVs are membranous particles that carry various bioactive molecules from their cellular origins, such as cytokines, nucleic acids, enzymes, lipids and proteins. EVs can mediate cell-to-cell communication and modulate various physiological processes, such as cell differentiation, angiogenesis, immune response and tissue remodelling. In this review, we summarize the recent advances in EV-based wound healing, focusing on the signalling pathways that are regulated by EVs and their cargos. We discuss how EVs derived from different types of stem/progenitor cells can promote wound healing and reduce scar formation by modulating the Wnt/β-catenin, phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin, vascular endothelial growth factor, transforming growth factor β and JAK-STAT pathways. Moreover, we also highlight the challenges and opportunities for engineering or modifying EVs to enhance their efficacy and specificity for wound healing.

Stem Cell-Based Therapy and Cell-Free Therapy as an Alternative Approach for Cardiac Regeneration

The World Health Organization reports that cardiovascular diseases (CVDs) represent 32% of all global deaths. The ineffectiveness of conventional therapies in CVDs encourages the development of novel, minimally invasive therapeutic strategies for the healing and regeneration of damaged tissue. The self-renewal capacity, multilineage differentiation, lack of immunogenicity, and immunosuppressive properties of mesenchymal stem cells (MSCs) make them a promising option for CVDs. However, growing evidence suggests that myocardial regeneration occurs through paracrine factors and extracellular vesicle (EV) secretion, rather than through differentiation into cardiomyocytes. Research shows that stem cells secrete or surface-shed into their culture media various cytokines, chemokines, growth factors, anti-inflammatory factors, and EVs, which constitute an MSC-conditioned medium (MSC-CM) or the secretome. The use of MSC-CM enhances cardiac repair through resident heart cell differentiation, proliferation, scar mass reduction, a decrease in infarct wall thickness, and cardiac function improvement comparable to MSCs without their side effects. This review highlights the limitations and benefits of therapies based on stem cells and their secretome as an innovative treatment of CVDs.

Transcriptional Targeting Approaches in Cardiac Gene Transfer Using AAV Vectors

Cardiac-targeted transgene delivery offers new treatment opportunities for cardiovascular diseases, which massively contribute to global mortality. Restricted gene transfer to cardiac tissue might protect extracardiac organs from potential side-effects. This could be mediated by using cis-regulatory elements, including promoters and enhancers that act on the transcriptional level. Here, we discuss examples of tissue-specific promoters for targeted transcription in myocytes, cardiomyocytes, and chamber-specific cardiomyocytes. Some promotors are induced at pathological states, suggesting a potential use as "induction-by-disease switches" in gene therapy. Recent developments have resulted in the identification of novel enhancer-elements that could further pave the way for future refinement of transcriptional targeting, for example, into the cardiac conduction system.

GLA-modified RNA treatment lowers GB3 levels in iPSC-derived cardiomyocytes from Fabry-affected individuals

Recent studies in non-human model systems have shown therapeutic potential of nucleoside-modified messenger RNA (modRNA) treatments for lysosomal storage diseases. Here, we assessed the efficacy of a modRNA treatment to restore the expression of the galactosidase alpha (GLA), which codes for α-Galactosidase A (α-GAL) enzyme, in a human cardiac model generated from induced pluripotent stem cells (iPSCs) derived from two individuals with Fabry disease. Consistent with the clinical phenotype, cardiomyocytes from iPSCs derived from Fabry-affected individuals showed accumulation of the glycosphingolipid Globotriaosylceramide (GB3), which is an α-galactosidase substrate. Furthermore, the Fabry cardiomyocytes displayed significant upregulation of lysosomal-associated proteins. Upon GLA modRNA treatment, a subset of lysosomal proteins were partially restored to wild-type levels, implying the rescue of the molecular phenotype associated with the Fabry genotype. Importantly, a significant reduction of GB3 levels was observed in GLA modRNA-treated cardiomyocytes, demonstrating that α-GAL enzymatic activity was restored. Together, our results validate the utility of iPSC-derived cardiomyocytes from affected individuals as a model to study disease processes in Fabry disease and the therapeutic potential of GLA modRNA treatment to reduce GB3 accumulation in the heart.

The promise of RNA-based therapeutics in revolutionizing heart failure management - a narrative review of current evidence

This review elucidates the potential of RNA-based therapeutics to revolutionize heart failure (HF) management. Through a comprehensive analysis of relevant studies, this review reveals the promising prospects of these novel interventions in personalized treatment strategies, targeted modulation of specific molecular pathways, and the attainment of synergistic effects via combination therapies. Moreover, the regenerative capacity of RNA-based therapeutics for cardiac repair and the inherent advantages associated with noninvasive routes of administration are explored. Additionally, the studies accentuate the significance of diligent monitoring of disease progression and treatment response, ensuring safety and considering long-term outcomes. While ongoing research endeavours and technological advancements persist in addressing extant challenges and limitations, the transformative potential of RNA-based therapeutics in HF management offers a beacon of hope for enhanced patient outcomes.