Acellular cardiac scaffolds enriched with MSC-derived extracellular vesicles limit ventricular remodelling and exert local and systemic immunomodulation in a myocardial infarction porcine model

Small extracellular vesicles associated miRNA in myocardial fibrosis

Myocardial fibrosis involves the loss of cardiomyocytes, myocardial fibroblast proliferation, and a reduction in angiogenesis, ultimately leading to heart failure, Given its significant implications, it is crucial to explore novel therapies for myocardial fibrosis. Recently one emerging avenue has been the use of small extracellular vesicles (sEV)-carried miRNA. In this review, we summarize the regulatory role of sEV-carried miRNA in myocardial fibrosis. We explored not only the potential diagnostic value of circulating miRNA as biomarkers for heart disease but also the therapeutic implications of sEV-carried miRNA derived from various cellular sources and applications of modified sEV. This exploration is paramount for researchers striving to develop innovative, cell-free therapies as potential drug candidates for the management of myocardial fibrosis.

Extracellular vesicle transfer of lncRNA H19 splice variants to cardiac cells

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.

Therapeutic Application of Extracellular Vesicles Derived from Mesenchymal Stem Cells in Domestic Animals

Recently, the therapeutic potential of extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) has been extensively studied in both human and veterinary medicine. EVs are nano-sized particles containing biological components commonly found in other biological materials. For that reason, EV isolation and characterization are critical to draw precise conclusions during their investigation. Research on EVs within veterinary medicine is still considered in its early phases, yet numerous papers were published in recent years. The conventional adult tissues for deriving MSCs include adipose tissue and bone marrow. Nonetheless, alternative sources such as synovial fluid, endometrium, gingiva, and milk have also been intermittently used. Fetal adnexa are amniotic membrane/fluid, umbilical cord and Wharton's jelly. Cells derived from fetal adnexa exhibit an intermediate state between embryonic and adult cells, demonstrating higher proliferative and differentiative potential and longer telomeres compared to cells from adult tissues. Summarized here are the principal and recent preclinical and clinical studies performed in domestic animals such as horse, cattle, dog and cat. To minimize the use of antibiotics and address the serious issue of antibiotic resistance as a public health concern, they will undoubtedly also be utilized in the future to treat infections in domestic animals. A number of concerns, including large-scale production with standardization of EV separation and characterization techniques, must be resolved for clinical application.

Large extracellular vesicles from induced pluripotent stem cell-marrow stem cells enhance limb angiogenesis via ERK/MAPK

Aim: This study aims to investigate the effects of large extracellular vesicles (EVs) induced by pluripotent stem cell-derived mesenchymal stem cells on lower limb ischemic disease and explore its potential mechanisms. Materials & methods: The pathology of muscles was accessed by H&E staining and immunofluorescence staining. In vitro, we conducted wound-healing assay, tube formation assay, RT qPCR, ELISA, RNA sequencing and proteomic analysis. Results: iMSCs-lEVs alleviated the injury of ischemic lower limb and promoted the recovery of lower limb function. In vitro, iMSCs-lEVs promoted the proliferation, migration, and angiogenesis of HMEC-1 cells by regulating the ERK/MAPK signing pathway. Conclusion: This study demonstrated that iMSCs-lEVs promoted endothelial cell angiogenesis via the ERK/MAPK signaling pathway, thereby improving function after lower limb ischemic injury.

Evolving Strategies for Extracellular Vesicles as Future Cardiac Therapeutics: From Macro- to Nano-Applications

Cardiovascular disease represents the foremost cause of mortality and morbidity worldwide, with a steadily increasing incidence due to the growth of the ageing population. Cardiac dysfunction leading to heart failure may arise from acute myocardial infarction (MI) as well as inflammatory- and cancer-related chronic cardiomyopathy. Despite pharmacological progress, effective cardiac repair represents an unmet clinical need, with heart transplantation being the only option for end-stage heart failure. The functional profiling of the biological activity of extracellular vesicles (EVs) has recently attracted increasing interest in the field of translational research for cardiac regenerative medicine. The cardioprotective and cardioactive potential of human progenitor stem/cell-derived EVs has been reported in several preclinical studies, and EVs have been suggested as promising paracrine therapy candidates for future clinical translation. Nevertheless, some compelling aspects must be properly addressed, including optimizing delivery strategies to meet patient needs and enhancing targeting specificity to the cardiac tissue. Therefore, in this review, we will discuss the most relevant aspects of the therapeutic potential of EVs released by human progenitors for cardiovascular disease, with a specific focus on the strategies that have been recently implemented to improve myocardial targeting and administration routes.

Navigating the Immunological Crossroads: Mesenchymal Stem/Stromal Cells as Architects of Inflammatory Harmony in Tissue-Engineered Constructs

In the dynamic landscape of tissue engineering, the integration of tissue-engineered constructs (TECs) faces a dual challenge-initiating beneficial inflammation for regeneration while avoiding the perils of prolonged immune activation. As TECs encounter the immediate reaction of the immune system upon implantation, the unique immunomodulatory properties of mesenchymal stem/stromal cells (MSCs) emerge as key navigators. Harnessing the paracrine effects of MSCs, researchers aim to craft a localized microenvironment that not only enhances TEC integration but also holds therapeutic promise for inflammatory-driven pathologies. This review unravels the latest advancements, applications, obstacles, and future prospects surrounding the strategic alliance between MSCs and TECs, shedding light on the immunological symphony that guides the course of regenerative medicine.

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.

Exosome-loaded decellularized tissue: Opening a new window for regenerative medicine

Mesenchymal stem cell-derived exosomes (MSCs-EXO) have received a lot of interest recently as a potential therapeutic tool in regenerative medicine. Extracellular vesicles (EVs) known as exosomes (EXOs) are crucial for cell-cell communication throughout a variety of activities including stress response, aging, angiogenesis, and cell differentiation. Exploration of the potential use of EXOs as essential therapeutic effectors of MSCs to encourage tissue regeneration was motivated by success in the field of regenerative medicine. EXOs have been administered to target tissues using a variety of methods, including direct, intravenous, intraperitoneal injection, oral delivery, and hydrogel-based encapsulation, in various disease models. Despite the significant advances in EXO therapy, various methods are still being researched to optimize the therapeutic applications of these nanoparticles, and it is not completely clear which approach to EXO administration will have the greatest effects. Here, we will review emerging developments in the applications of EXOs loaded into decellularized tissues as therapeutic agents for use in regenerative medicine in various tissues.

Advancing Tissue Damage Repair in Geriatric Diseases: Prospects of Combining Stem Cell-Derived Exosomes with Hydrogels

Geriatric diseases are a group of diseases with unique characteristics related to senility. With the rising trend of global aging, senile diseases now mainly include endocrine, cardiovascular, neurodegenerative, skeletal, and muscular diseases and cancer. Compared with younger populations, the structure and function of various cells, tissues and organs in the body of the elderly undergo a decline as they age, rendering them more susceptible to external factors and diseases, leading to serious tissue damage. Tissue damage presents a significant obstacle to the overall health and well-being of older adults, exerting a profound impact on their quality of life. Moreover, this phenomenon places an immense burden on families, society, and the healthcare system.In recent years, stem cell-derived exosomes have become a hot topic in tissue repair research. The combination of these exosomes with biomaterials allows for the preservation of their biological activity, leading to a significant improvement in their therapeutic efficacy. Among the numerous biomaterial options available, hydrogels stand out as promising candidates for loading exosomes, owing to their exceptional properties. Due to the lack of a comprehensive review on the subject matter, this review comprehensively summarizes the application and progress of combining stem cell-derived exosomes and hydrogels in promoting tissue damage repair in geriatric diseases. In addition, the challenges encountered in the field and potential prospects are presented for future advancements.

Preclinical Models of Cardiac Disease: A Comprehensive Overview for Clinical Scientists

For recent decades, cardiac diseases have been the leading cause of death and morbidity worldwide. Despite significant achievements in their management, profound understanding of disease progression is limited. The lack of biologically relevant and robust preclinical disease models that truly grasp the molecular underpinnings of cardiac disease and its pathophysiology attributes to this stagnation, as well as the insufficiency of platforms that effectively explore novel therapeutic avenues. The area of fundamental and translational cardiac research has therefore gained wide interest of scientists in the clinical field, while the landscape has rapidly evolved towards an elaborate array of research modalities, characterized by diverse and distinctive traits. As a consequence, current literature lacks an intelligible and complete overview aimed at clinical scientists that focuses on selecting the optimal platform for translational research questions. In this review, we present an elaborate overview of current in vitro, ex vivo, in vivo and in silico platforms that model cardiac health and disease, delineating their main benefits and drawbacks, innovative prospects, and foremost fields of application in the scope of clinical research incentives.

Extracellular vesicles derived from HuMSCs alleviate daunorubicin-induced cardiac microvascular injury via miR-186-5p/PARP9/STAT1 signal pathway

Introduction

It is essential to acknowledge that the cardiovascular toxicity associated with anthracycline drugs can be partially attributed to the damage inflicted on blood vessels and endothelial cells. Extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) have the potential to repair cellular processes and promote tissue regeneration through the transfer of signaling molecules such as miRNAs. In the present study, we investigated the effects of MSC-EVs on daunorubicin (DNR)-damaged human cardiac microvascular endothelial cells (HCMEC) and developing blood vessels of Chicken Chorioallantoic Membrane (CAM) in vivo.

Materials and methods

We constructed in vitro and in vivo models of DNR-damaged endothelial cells and developing blood vessel. Scratch wound assays, EdU assays, tube formation assays, and SA-β-Gal staining were used to evaluate the effects of MSC-EVs on cell migration, proliferation, angiogenesis capacity and cell senescence. Blood vessel area was used to assess the effects of MSC-EVs on CAM vasculature. RT-qPCR was used to detect the mRNA expression levels of inflammatory molecules. RNA sequencing was employed to compare differential gene expression and downstream regulatory mechanisms. RNA interference experiments and miRNA mimic overexpression experiments were used to validate the regulatory effects of target genes and downstream signaling pathways.

Results

We found that MSC-EVs improved the migration, proliferation, and angiogenesis of HCMEC, while also alleviating cellular senescence. The angiogenic effect on the developing blood vessels was confirmed in vivo. We identified that MSC-EVs downregulated the expression of PARP9, thereby inhibiting the STAT1/pSTAT1 signaling pathway. This downregulation effect is likely mediated by the transfer of miR-186-5p from MSC-EVs to HCMEC. Overexpression of miR-186-5p in DNR-damaged HCMEC also exhibited the aforementioned downregulation effect. In vivo, the introduction of miR-186-5p mimics enhanced angiogenesis in the CAM model.

Conclusions

To summarize, our study reveals that MSC-EVs can restore the cellular function of DNR-damaged HCMEC and alleviate cellular senescence through the miR-185-5p-PARP9-STAT1/pSTAT1 pathway. This finding highlights the potential of MSC-EVs as a therapeutic strategy for mitigating the detrimental effects of anthracycline-induced endothelial damage.

Heparinized Acellular Hydrogels for Magnetically Induced Wound Healing Applications

The control of angiogenesis has the potential to be used for regulation of several pathological and physiological processes, which can be instrumental on the development of anticancer and wound healing therapeutical approaches. In this study, mesenchymal stem/stromal cells (MSCs) were seeded on magnetic-responsive gelatin, with or without heparin functionalization, and exposed to a static 0.08 T magnetic field (MF), for controlling their anti-inflammatory and angiogenic activity, with the aim of accelerating tissue healing. For the first time, it was examined how the amount of heparin and magnetic nanoparticles (MNPs) distributed on gelatin scaffolds affected the mechanical properties of the hydrogels and the morphology, proliferation, and secretome profiling of MSCs. The findings demonstrated that the addition of MNPs and heparin affects the hydrogel swelling capacity and renders distinct MSC proliferation rates. Additionally, MF acts as a topographical cue to guide MSCs alignment and increases the level of expression of specific genes and proteins that promote angiogenesis. The results also suggested that the presence of higher amounts of heparin (10 μg/cm3) interferes with the secretion and limits the capacity of angiogenic factors to diffuse through the hydrogel and into the culture medium. Ultimately, this study shows that acellular heparinized hydrogels efficiently retain the angiogenic growth factors released by magnetically stimulated MSCs thus rendering superior wound contraction (55.8% ± 0.4%) and cell migration rate (49.4% ± 0.4%), in comparison to nonheparinized hydrogels (35.2% ± 0.7% and 37.8% ± 0.7%, respectively). Therefore, these heparinized magnetic hydrogels can be used to facilitate angiogenesis in various forms of tissue damage including bone defects, skin wounds, and cardiovascular diseases, leading to enhanced tissue regeneration.

Enhancing Immunomodulatory Function of Mesenchymal Stromal Cells by Hydrogel Encapsulation

Mesenchymal stromal cells (MSCs) showcase remarkable immunoregulatory capabilities in vitro, positioning them as promising candidates for cellular therapeutics. However, the process of administering MSCs and the dynamic in vivo environment may impact the cell-cell and cell-matrix interactions of MSCs, consequently influencing their survival, engraftment, and their immunomodulatory efficacy. Addressing these concerns, hydrogel encapsulation emerges as a promising solution to enhance the therapeutic effectiveness of MSCs in vivo. Hydrogel, a highly flexible crosslinked hydrophilic polymer with a substantial water content, serves as a versatile platform for MSC encapsulation. Demonstrating improved engraftment and heightened immunomodulatory functions in vivo, MSCs encapsulated by hydrogel are at the forefront of advancing therapeutic outcomes. This review delves into current advancements in the field, with a focus on tuning various hydrogel parameters to elucidate mechanistic insights and elevate functional outcomes. Explored parameters encompass hydrogel composition, involving monomer type, functional modification, and co-encapsulation, along with biomechanical and physical properties like stiffness, viscoelasticity, topology, and porosity. The impact of these parameters on MSC behaviors and immunomodulatory functions is examined. Additionally, we discuss potential future research directions, aiming to kindle sustained interest in the exploration of hydrogel-encapsulated MSCs in the realm of immunomodulation.

miR-135a Mediates Mitochondrial Oxidative Respiratory Function through SIRT1 to Regulate Atrial Fibrosis

INTRODUCTION

This study aimed to explore the function of miR-135a in the progress of atrial fibrosis and the mechanism of miR-135a/SIRT1 (sirtuin 1) in human cardiac fibroblasts and mouse cardiac fibroblasts (MCFs) mediating the regulation of atrial fibrosis by mitochondrial oxidative respiration function.

METHODS

Using Ang II (angiotensin II) to induce fibrosis in HCFs (human corneal fibroblasts) and MCF (Michigan Cancer Foundation, MCF) cells in vitro, the miRNA-seq results of previous studies were validated. Proliferative and invasive ability of HCFs and MCFs was detected by Cell Counting Kit-8 assay (CCK-8) and scratch experiment after overexpressing miR-135a in HCFs and MCF cells. Protein and mRNA expression was tested using Western blot and qPCR. The target of miR-135a was verified as SIRT1 by a luciferase reporter assay and the activities of the mitochondrial respiratory enzyme complexes I, II, III, and IV were determined colorimetrically. The activities of malondialdehyde, reactive oxygen species, and superoxide dismutase in cells were detected with enzyme-linked immunosorbent assay (ELISA).

RESULTS

miR-135a expression was elevated in HCFs and MCFs cells in the Ang II group than control group. Overexpression of miR-135a could promote the proliferation, migration, oxidative stress, as well as fibrosis of cardiac fibroblasts and suppresses mitochondrial activity. In addition, we found SIRT1 was a target gene of miR-135a. What is more, the findings showed miR-135a promoted fibrosis in HCFs and MCFs cells acting through regulation of SIRT1.

CONCLUSIONS

miR-135a mediates mitochondrial oxidative respiratory function through SIRT1 to regulate atrial fibrosis.

Exosomes-mediated drug delivery for the treatment of myocardial injury

Cardiovascular disease has become a major cause of death worldwide. Myocardial injury (MI) caused by myocardial infarction, myocarditis, and drug overdose can lead to impaired cardiac function, culminating in serious consequences such as angina pectoris, arrhythmias, and heart failure. Exosomes exhibit high biocompatibility and target specificity, rendering them an important non-cellular therapy for improving MI. Exosomes are diminutive vesicles that encapsulate nucleic acids and proteins. Exosomes derived from cardiac stem cells themselves have therapeutic effects, and they can also serve as carriers to deliver therapeutic drugs to recipient cells, thereby exerting a therapeutic effect. The molecules within exosomes are encapsulated in a lipid bilayer, allowing them to stably exist in body fluids without being affected by nucleases. Therefore, the utilization of exosomes as drug delivery systems (DDS) for disease treatment has been extensively investigated and is currently undergoing clinical trials. This review summarizes the therapeutic effects of exosomes on MI and provides an overview of current research progress on their use as DDS in MI.

Extracellular Vesicles in Domestic Animals: Cellular Communication in Health and Disease

Apoptotic and healthy cells of domestic animals release membrane-enclosed particles from their plasma membrane. These special structures, called extracellular vesicles, play an important role in intercellular communication. In the past, it was believed that their function was mainly to dispose unwanted cell contents and to help maintain cell homeostasis. However, we now know that they have important roles in health and disease and have diagnostic value as well as great potential for therapy in veterinary medicine. Extracellular vesicles facilitate cellular exchanges by delivering functional cargo molecules to nearby or distant tissues. They are produced by various cell types and are found in all body fluids. Their cargo reflects the state of the releasing parent cell, and despite their small size, this cargo is extraordinarily complex. Numerous different types of molecules contained in vesicles make them an extremely promising tool in the field of regenerative veterinary medicine. To further increase research interest and discover their full potential, some of the basic biological mechanisms behind their function need to be better understood. Only then will we be able to maximize the clinical relevance for targeted diagnostic and therapeutic purposes in various domestic animal species.

Mechanisms and therapeutic strategies of extracellular vesicles in cardiovascular diseases

Cardiovascular disease (CVD) significantly impacts global society since it is the leading cause of death and disability worldwide, and extracellular vesicle (EV)-based therapies have been extensively investigated. EV delivery is involved in mediating the progression of CVDs and has great potential to be biomarker and therapeutic molecular carrier. Besides, EVs from stem cells and cardiac cells can effectively protect the heart from various pathologic conditions, and then serve as an alternative treatment for CVDs. Moreover, the research of using EVs as delivery carriers of therapeutic molecules, membrane engineering modification of EVs, or combining EVs with biomaterials further improves the application potential of EVs in clinical treatment. However, currently there are only a few articles summarizing the application of EVs in CVDs. This review provides an overview of the role of EVs in the pathogenesis and diagnosis of CVDs. It also focuses on how EVs promote the repair of myocardial injury and therapeutic methods of CVDs. In conclusion, it is of great significance to review the research on the application of EVs in the treatment of CVDs, which lays a foundation for further exploration of the role of EVs, and clarifies the prospect of EVs in the treatment of myocardial injury.

Combined Application of Human Amniotic Membrane Mesenchymal Stem Cells and a Modified PGS-co-PCL Film in an Experimental Model of Myocardial Ischemia-Reperfusion Injury

According to the World Health Organization (WHO), about 3.9 million people die annually of ischemic heart disease (IHD). Several clinical trials have shown that stem cell therapy is a promising therapeutic approach to IHD. Human amniotic membrane mesenchymal stem cells (hAMSCs) positively affect the repair of myocardial ischemia-reperfusion (MI/R) injury by stimulating endogenous repair mechanisms. The differentiated hAMSCs with and without modified PGS-co-PCL film were applied in the myocardium. MI/R injury was induced by ligating the left anterior descending artery in 48 male Wistar rats. The rats were divided into four groups, (n = 12) animals: heart failure (HF) as the control group, HF + MSCs, HF + MSCs + film, and HF + film. Echocardiography was performed 2 and 4 weeks after MI/R injury moreover the expression of the VEGF protein was assessed in the rat heart tissue via immunohistochemistry. In vitro, our result shows fantastic cell survival when seeded on film. In vivo, the left ventricle ejection fraction (LEVD), fractional shortening (FS), end-diastolic (EDV), and stroke volume (SV) have been increased and systolic volumes decreased in all treatment groups in comparison with control. Although combination therapy has a more positive effect on hemodynamic parameters, there is no significant difference between HF + MSCs + film with other treatment groups. Also, In the IHC assay, expression of the VEGF protein significantly increased in all intervention groups. The implantation of MSCs and the modified film significantly enhanced the cardiac functional outcome; in this regard, enhancement in cell survival and VEGF expression are involved as underlying mechanisms in which cardiac film and MSCs exert a beneficial effect.

Combinatorial Effect of Biomaterials and Extracellular Vesicle Therapy for Heart Failure with Reduced Ejection Fraction: A Systematic Review of Preclinical Studies

Heart failure, a pervasive global health burden, necessitates innovative therapeutic strategies. Extracellular vesicles (EVs) have emerged as promising contenders for cardiac repair, owing to their profound influence on fibrosis and inflammation. Merging EVs with biomaterials holds the potential for a synergistic leap in therapeutic efficacy. In this review, the impact of combining EVs with biomaterials in preclinical heart failure models is scrutinized. Fifteen studies, predominantly employing mesenchymal stromal cell-derived EVs along with hyaluronic acid or peptides in coronary ligation models, meet these stringent criteria. The amalgamation of EVs and biomaterials consistently enhances cardiac ejection fraction (1.39; 95% CI: 0.68, 2.11; p = 0.0001) and fractional shortening (1.46, 95% CI: 0.70, 2.22; p = 0.0002) compared to EV monotherapy. Secondary outcomes similarly showcased improvement in the combined treatment group. Although the number of studies analyzed is modest, no indications of publication bias surface. In summary, combination therapy with EVs and biomaterials enhances therapeutic benefit in preclinical heart failure models. The consistent improvement observed across diverse EV sources, biomaterials, and animal models underscores the exciting potential of this synergistic approach.

Mechanisms and Optimization Strategies of Paracrine Exosomes from Mesenchymal Stem Cells in Ischemic Heart Disease

The morbidity and mortality of myocardial infarction (MI) are increasing worldwide. Mesenchymal stem cells (MSCs) are multipotent stem cells with self-renewal and differentiation capabilities that are essential in tissue healing and regenerative medicine. However, the low implantation and survival rates of transplanted cells hinder the widespread clinical use of stem cells. Exosomes are naturally occurring nanovesicles that are secreted by cells and promote the repair of cardiac function by transporting noncoding RNA and protein. In recent years, MSC-derived exosomes have been promising cell-free treatment tools for improving cardiac function and reversing cardiac remodeling. This review describes the biological properties and therapeutic potential of exosomes and summarizes some engineering approaches for exosomes optimization to enhance the targeting and therapeutic efficacy of exosomes in MI.

Controlled extracellular vesicles release from aminoguanidine nanoparticle-loaded polylysine hydrogel for synergistic treatment of spinal cord injury

Pharmaceutical treatments are critical for the acute and subacute phases of spinal cord injury (SCI) and significantly impact patients' prognoses. However, there is a lack of a precise, multitemporal, integrated drug delivery system for medications administered in both phases. In this study, we prepare a hybrid polylysine-based hydrogel (PBHEVs@AGN) comprising short-term release of pH-responsive aminoguanidine nanoparticles (AGN) and sustained release of extracellular vesicles (EVs) for synergistic SCI treatment. When AGN is exposed to the acidic environment at the injury site, it quickly diffuses out of the hydrogel and releases the majority of the aminoguanidine within 24 h, reducing oxidative stress in lesion tissues. Enriched EVs are gradually released from the hydrogel and remain in the tissue for weeks, providing a long-term anti-inflammatory effect and further ensuring axonal regeneration. Fast-releasing aminoguanidine can cooperate with slow-release EVs to treat SCI more effectively by reducing the production of proinflammatory cytokines and blocking the TLR4/Myd88/NF-κB inflammatory pathway, creating a sustained anti-inflammatory microenvironment for SCI recovery. Our in vivo experiments demonstrate that PBHEVs@AGN reduces the occurrence of scar tissue, encourages remyelination, and speeds up axonal regeneration. Herein, this multi-drug delivery system, which combines the acute release of aminoguanidine and the sustained release of EVs is highly effective for synergistically managing the challenging pathological processes after SCI.

Current optimized strategies for stem cell-derived extracellular vesicle/exosomes in cardiac repair

Ischemic heart diseases remain the leading cause of death globally, and stem cell-based therapy has been investigated as a potential approach for cardiac repair. Due to poor survival and engraftment in the cardiac ischemic milieu post transplantation, the predominant therapeutic effects of stem cells act via paracrine actions, by secreting extracellular vesicles (EVs) and/or other factors. Exosomes are nano-sized EVs of endosomal origin, and now viewed as a major contributor in facilitating myocardial repair and regeneration. However, EV/exosome therapy has major obstacles before entering clinical settings, such as limited production yield, unstable biological activity, poor homing efficiency, and low tissue retention. This review aims to provide an overview of the biogenesis and mechanisms of stem cell-derived EV/exosomes in the process of cardiac repair and discuss the current advancements in different optimized strategies to produce high-yield EV/exosomes with higher bioactivity, or engineer them with improved homing efficiency and therapeutic potency. In particular, we outline recent findings toward preclinical and clinical translation of EV/exosome therapy in ischemic heart diseases, and discuss the potential barriers in regard to clinical translation of EV/exosome therapy.

Insight into extracellular vesicles in vascular diseases: intercellular communication role and clinical application potential

BACKGROUND

Cells have been increasingly known to release extracellular vesicles (EVs) to the extracellular environment under physiological and pathological conditions. A plethora of studies have revealed that EVs contain cell-derived biomolecules and are found in circulation, thereby implicating them in molecular trafficking between cells. Furthermore, EVs have an effect on physiological function and disease development and serve as disease biomarkers.

MAIN BODY

Given the close association  between EV circulation and vascular disease, this review aims to provide a brief introduction to EVs, with a specific focus on the EV cargoes participating in pathological mechanisms, diagnosis, engineering, and clinical potential, to highlight the emerging evidence suggesting promising targets in vascular diseases. Despite the expansion of research in this field, some noticeable limitations remain for clinical translational research.

CONCLUSION

This review makes a novel contribution to a summary of recent advances and a perspective on the future of EVs in vascular diseases. Video Abstract.

Cell or cell derivative-laden hydrogels for myocardial infarction therapy: from the perspective of cell types

Myocardial infarction (MI) is a global cardiovascular disease with high mortality and morbidity. To treat acute MI, various therapeutic approaches have been developed, including cells, extracellular vesicles, and biomimetic nanoparticles. However, the clinical application of these therapies is limited due to low cell viability, inadequate targetability, and rapid elimination from cardiac sites. Injectable hydrogels, with their three-dimensional porous structure, can maintain the biomechanical stabilization of hearts and the transplantation activity of cells. However, they cannot regenerate cardiomyocytes or repair broken hearts. A better understanding of the collaborative relationship between hydrogel delivery systems and cell or cell-inspired therapy will facilitate advancing innovative therapeutic strategies against MI. Following that, from the perspective of cell types, MI progression and recent studies on using hydrogel to deliver cell or cell-derived preparations for MI treatment are discussed. Finally, current challenges and future prospects of cell or cell derivative-laden hydrogels for MI therapy are proposed.

Engineered Vesicles and Hydrogel Technologies for Myocardial Regeneration

Increased prevalence of cardiovascular disease and potentially life-threatening complications of myocardial infarction (MI) has led to emerging therapeutic approaches focusing on myocardial regeneration and restoration of physiologic function following infarction. Extracellular vesicle (EV) technology has gained attention owing to the biological potential to modulate cellular immune responses and promote the repair of damaged tissue. Also, EVs are involved in local and distant cellular communication following damage and play an important role in initiating the repair process. Vesicles derived from stem cells and cardiomyocytes (CM) are of particular interest due to their ability to promote cell growth, proliferation, and angiogenesis following MI. Although a promising candidate for myocardial repair, EV technology is limited by the short retention time of vesicles and rapid elimination by the body. There have been several successful attempts to address this shortcoming, which includes hydrogel technology for the sustained bioavailability of EVs. This review discusses and summarizes current understanding regarding EV technology in the context of myocardial repair.

Application of locally responsive design of biomaterials based on microenvironmental changes in myocardial infarction

Morbidity and mortality caused by acute myocardial infarction (AMI) are on the rise, posing a grave threat to the health of the general population. Up to now, interventional, surgical, and pharmaceutical therapies have been the main treatment methods for AMI. Effective and timely reperfusion therapy decreases mortality, but it cannot stimulate myocardial cell regeneration or reverse ventricular remodeling. Cell therapy, gene therapy, immunotherapy, anti-inflammatory therapy, and several other techniques are utilized by researchers to improve patients' prognosis. In recent years, biomaterials for AMI therapy have become a hot spot in medical care. Biomaterials furnish a microenvironment conducive to cell growth and deliver therapeutic factors that stimulate cell regeneration and differentiation. Biomaterials adapt to the complex microenvironment and respond to changes in local physical and biochemical conditions. Therefore, environmental factors and material properties must be taken into account when designing biomaterials for the treatment of AMI. This article will review the factors that need to be fully considered in the design of biological materials.

Prospect of Mesenchymal Stem-Cell-Conditioned Medium in the Treatment of Acute Pancreatitis: A Systematic Review

Mesenchymal stem cells (MSCs) have demonstrated potential in both clinical and pre-clinical research for mitigating tissue damage and inflammation associated with acute pancreatitis (AP) via paracrine mechanisms. Hence, there has been a recent surge of interest among researchers in utilizing MSC cultured medium (CM) and its components for the treatment of AP, which is recognized as the primary cause of hospitalization for gastrointestinal disorders globally. A systematic review was conducted by searching the MEDLINE, EMBASE, and Web of Science databases. Studies that involve the administration of MSC-CM, extracellular vesicles/microvesicles (EVs/MVs), or exosomes to AP animal models are included. A total of six research studies, including eight experiments, were identified as relevant. The findings of this study provide evidence in favor of a beneficial impact of MSC-CM on both clinical and immunological outcomes. Nevertheless, prior to clinical trials, large animal models should be used and prolonged observation periods conducted in pre-clinical research. Challenges arise due to the lack of standardization and consensus on isolation processes, quantifications, and purity testing, making it difficult to compare reports and conduct meta-analyses in MSC-CM-based therapies.

Exosomal Non-Coding RNA Mediates Macrophage Polarization: Roles in Cardiovascular Diseases

Extracellular vesicles (EVs) or exosomes are nanosized extracellular particles that contain proteins, DNA, non-coding RNA (ncRNA) and other molecules, which are widely present in biofluids throughout the body. As a key mediator of intercellular communication, EVs transfer their cargoes to target cells and activate signaling transduction. Increasing evidence shows that ncRNA is involved in a variety of pathological and physiological processes through various pathways, particularly the inflammatory response. Macrophage, one of the body's "gatekeepers", plays a crucial role in inflammatory reactions. Generally, macrophages can be classified as pro-inflammatory type (M1) or anti-inflammatory type (M2) upon their phenotypes, a phenomenon termed macrophage polarization. Increasing evidence indicates that the polarization of macrophages plays important roles in the progression of cardiovascular diseases (CVD). However, the role of exosomal ncRNA in regulating macrophage polarization and the role of polarized macrophages as an important source of EV in CVD remains to be elucidated. In this review, we summarize the role and molecular mechanisms of exosomal-ncRNA in regulating macrophage polarization during CVD development, focusing on their cellular origins, functional cargo, and their detailed effects on macrophage polarization. We also discuss the role of polarized macrophages and their derived EV in CVD as well as the therapeutic prospects of exosomal ncRNA in the treatment of CVD.

Cardiac tissue engineering for myocardial infarction treatment

Myocardial infarction is one of the major causes of morbidity and mortality worldwide. Current treatments can relieve the symptoms of myocardial ischemia but cannot repair the necrotic myocardial tissue. Novel therapeutic strategies based on cellular therapy, extracellular vesicles, non-coding RNAs and growth factors have been designed to restore cardiac function while inducing cardiomyocyte cycle re-entry, ensuring angiogenesis and cardioprotection, and preventing ventricular remodeling. However, they face low stability, cell engraftment issues or enzymatic degradation in vivo, and it is thus essential to combine them with biomaterial-based delivery systems. Microcarriers, nanocarriers, cardiac patches and injectable hydrogels have yielded promising results in preclinical studies, some of which are currently being tested in clinical trials. In this review, we cover the recent advances made in cellular and acellular therapies used for cardiac repair after MI. We present current trends in cardiac tissue engineering related to the use of microcarriers, nanocarriers, cardiac patches and injectable hydrogels as biomaterial-based delivery systems for biologics. Finally, we discuss some of the most crucial aspects that should be addressed in order to advance towards the clinical translation of cardiac tissue engineering approaches.

Oncostatin M-Enriched Small Extracellular Vesicles Derived from Mesenchymal Stem Cells Prevent Isoproterenol-Induced Fibrosis and Enhance Angiogenesis

Myocardial fibrosis is a pathological hallmark of cardiac dysfunction. Oncostatin M (OSM) is a pleiotropic cytokine that can promote fibrosis in different organs after sustained exposure. However, OSM released by macrophages during cardiac fibrosis suppresses cardiac fibroblast activation by modulating transforming growth factor beta 1 (TGF-β1) expression and extracellular matrix deposition. Small extracellular vesicles (SEVs) from mesenchymal stromal cells (MSCs) are being investigated to treat myocardial infarction, using different strategies to bolster their therapeutic ability. Here, we generated TERT-immortalized human MSC cell lines (MSC-T) engineered to overexpress two forms of cleavage-resistant OSM fused to CD81TM (OSM-SEVs), which allows the display of the cytokine at the surface of secreted SEVs. The therapeutic potential of OSM-SEVs was assessed in vitro using human cardiac ventricular fibroblasts (HCF-Vs) activated by TGF-β1. Compared with control SEVs, OSM-loaded SEVs reduced proliferation in HCF-V and blunted telo-collagen expression. When injected intraperitoneally into mice treated with isoproterenol, OSM-loaded SEVs reduced fibrosis, prevented cardiac hypertrophy, and increased angiogenesis. Overall, we demonstrate that the enrichment of functional OSM on the surface of MSC-T-SEVs increases their potency in terms of anti-fibrotic and pro-angiogenic properties, which opens new perspectives for this novel biological product in cell-free-based therapies.

Gene expression patterns and related pathways in the hearts of rhesus monkeys subjected to prolonged myocardial ischemia

After myocardial infarction (MI) occurs, progressive pathological cardiac remodeling results in heart dysfunction and even heart failure during the following months or years. The present study explored the molecular mechanisms underlying the late phase of MI at the global transcript level. A rhesus monkey model of myocardial ischemia induced by left anterior descending (LAD) artery ligation was established, and the heart tissue was collected eight weeks after ligation for transcriptome analysis by DNA microarray technology. Differentially expressed genes in the core infarcted area and remote infarcted area of the ischemic heart were detected with significance analysis of microarray (SAM), and related pathways were detected by Gene Ontology (GO)/pathway analysis. We found that compared to the sham condition, prolonged ischemia increased the levels of 941 transcripts, decreased the levels of 380 transcripts in the core infarcted area, and decreased the levels of 8 transcripts in the remote area in monkey heart tissue. Loss of coordination between the expression of genes, including natriuretic peptide A (NPPA), NPPB, and corin (Corin, serine peptidase), may aggravate cardiac remodeling. Furthermore, imbalance in the enriched significantly changed pathways, including fibrosis-related pathways, cardioprotective pathways, and the cardiac systolic pathway, likely also plays a key role in regulating the development of heart remodeling.

The role of major immune cells in myocardial infarction

Myocardial infarction (MI) is a cardiovascular disease (CVD) with high morbidity and mortality worldwide, often leading to adverse cardiac remodeling and heart failure, which is a serious threat to human life and health. The immune system makes an important contribution to the maintenance of normal cardiac function. In the disease process of MI, necrotic cardiomyocytes release signals that activate nonspecific immunity and trigger the action of specific immunity. Complex immune cells play an important role in all stages of MI progression by removing necrotic cardiomyocytes and tissue and promoting the healing of damaged tissue cells. With the development of biomaterials, cardiac patches have become an emerging method of repairing MI, and the development of engineered cardiac patches through the construction of multiple animal models of MI can help treat MI. This review introduces immune cells involved in the development of MI, summarizes the commonly used animal models of MI and the newly developed cardiac patch, so as to provide scientific reference for the accurate diagnosis and effective treatment of MI.

Extracellular vesicles mediate biological information delivery: A double-edged sword in cardiac remodeling after myocardial infarction

Acute myocardial infarction (AMI) is a severe ischemic disease with high morbidity and mortality worldwide. Maladaptive cardiac remodeling is a series of abnormalities in cardiac structure and function that occurs following myocardial infarction (MI). The pathophysiology of this process can be separated into two distinct phases: the initial inflammatory response, and the subsequent longer-term scar revision that includes the regression of inflammation, neovascularization, and fibrotic scar formation. Extracellular vesicles are nano-sized lipid bilayer vesicles released into the extracellular environment by eukaryotic cells, containing bioinformatic transmitters which are essential mediators of intercellular communication. EVs of different cellular origins play an essential role in cardiac remodeling after myocardial infarction. In this review, we first introduce the pathophysiology of post-infarction cardiac remodeling, as well as the biogenesis, classification, delivery, and functions of EVs. Then, we explore the dual role of these small molecule transmitters delivered by EVs in post-infarction cardiac remodeling, including the double-edged sword of pro-and anti-inflammation, and pro-and anti-fibrosis, which is significant for post-infarction cardiac repair. Finally, we discuss the pharmacological and engineered targeting of EVs for promoting heart repair after MI, thus revealing the potential value of targeted modulation of EVs and its use as a drug delivery vehicle in the therapeutic process of post-infarction cardiac remodeling.

Can Extracellular Vesicles as Drug Delivery Systems Be a Game Changer in Cardiac Disease?

Cardiac diseases such as myocardial infarction and heart failure have been the leading cause of death worldwide for more than 20 years, and new treatments continue to be investigated. Heart transplantation, a curative treatment for severe cardiac dysfunction, is available to only a small number of patients due to the rarity of donors and high costs. Cardiac regenerative medicine using embryonic stem cells and induced pluripotent stem cells is expected to be a new alternative to heart transplantation, but it has problems such as induction of immune response, tumor formation, and low survival rate of transplanted cells. On the other hand, there has been a focus on cell-free therapy using extracellular vesicles (EVs) due to their high biocompatibility and target specificity. Exosomes, one type of EV, play a role in the molecular transport system in vivo and can be considered a drug delivery system (DDS) innate to all living things. Exosomes contain nucleic acids and proteins, which are transported from secretory cells to recipient cells. Molecules in exosomes are encapsulated in a lipid bilayer, which allows them to exist stably in body fluids without being affected by nuclease degradation enzymes. Therefore, the therapeutic use of exosomes as DDSs has been widely explored and is being used in clinical trials and other clinical settings. This review summarizes the current topics of EVs as DDSs in cardiac disease.

Expression Profile of Housekeeping Genes and Tissue-Specific Genes in Multiple Tissues of Pigs

Pigs have become an ideal model system for human disease research and development and an important farm animal that provides a valuable source of nutrition. To profile the all-sided gene expression and their biological functions across multiple tissues, we conducted a comprehensive analysis of gene expression on a large scale around the side of housekeeping genes (HKGs), tissue specific genes (TSGs), and the co-expressed genes in 14 various tissues. In this study, we identified 2351 HKGs and 3018 TSGs across tissues, among which 4 HKGs (COX1, UBB, OAZ1/NPFF) exhibited low variation and high expression levels, and 31 particular TSGs (e.g., PDC, FKBP6, STAT2, and COL1A1) were exclusively expressed in several tissues, including endocrine brain, ovaries, livers, backfat, jejunum, kidneys, lungs, and longissimus dorsi muscles. We also obtained 17 modules with 230 hub genes (HUBGs) by weighted gene co-expression network analysis. On the other hand, HKGs functions were enriched in the signaling pathways of the ribosome, spliceosome, thermogenesis, oxidative phosphorylation, and nucleocytoplasmic transport, which have been highly suggested to involve in the basic biological tissue activities. While TSGs were highly enriched in the signaling pathways that were involved in specific physiological processes, such as the ovarian steroidogenesis pathway in ovaries and the renin-angiotensin system pathway in kidneys. Collectively, these stable, specifical, and co-expressed genes provided useful information for the investigation of the molecular mechanism for an understanding of the genetic and biological processes of complex traits in pigs.

Scalable Generation of Nanovesicles from Human-Induced Pluripotent Stem Cells for Cardiac Repair

Extracellular vesicles (EVs) from stem cells have shown significant therapeutic potential to repair injured cardiac tissues and regulate pathological fibrosis. However, scalable generation of stem cells and derived EVs for clinical utility remains a huge technical challenge. Here, we report a rapid size-based extrusion strategy to generate EV-like membranous nanovesicles (NVs) from easily sourced human iPSCs in large quantities (yield 900× natural EVs). NVs isolated using density-gradient separation (buoyant density 1.13 g/mL) are spherical in shape and morphologically intact and readily internalised by human cardiomyocytes, primary cardiac fibroblasts, and endothelial cells. NVs captured the dynamic proteome of parental cells and include pluripotency markers (LIN28A, OCT4) and regulators of cardiac repair processes, including tissue repair (GJA1, HSP20/27/70, HMGB1), wound healing (FLNA, MYH9, ACTC1, ILK), stress response/translation initiation (eIF2S1/S2/S3/B4), hypoxia response (HMOX2, HSP90, GNB1), and extracellular matrix organization (ITGA6, MFGE8, ITGB1). Functionally, NVs significantly promoted tubule formation of endothelial cells (angiogenesis) (p < 0.05) and survival of cardiomyocytes exposed to low oxygen conditions (hypoxia) (p < 0.0001), as well as attenuated TGF-β mediated activation of cardiac fibroblasts (p < 0.0001). Quantitative proteome profiling of target cell proteome following NV treatments revealed upregulation of angiogenic proteins (MFGE8, MYH10, VDAC2) in endothelial cells and pro-survival proteins (CNN2, THBS1, IGF2R) in cardiomyocytes. In contrast, NVs attenuated TGF-β-driven extracellular matrix remodelling capacity in cardiac fibroblasts (ACTN1, COL1A1/2/4A2/12A1, ITGA1/11, THBS1). This study presents a scalable approach to generating functional NVs for cardiac repair.

Breakthrough of extracellular vesicles in pathogenesis, diagnosis and treatment of osteoarthritis

Osteoarthritis (OA) is a highly prevalent whole-joint disease that causes disability and pain and affects a patient's quality of life. However, currently, there is a lack of effective early diagnosis and treatment. Although stem cells can promote cartilage repair and treat OA, problems such as immune rejection and tumorigenicity persist. Extracellular vesicles (EVs) can transmit genetic information from donor cells and mediate intercellular communication, which is considered a functional paracrine factor of stem cells. Increasing evidences suggest that EVs may play an essential and complex role in the pathogenesis, diagnosis, and treatment of OA. Here, we introduced the role of EVs in OA progression by influencing inflammation, metabolism, and aging. Next, we discussed EVs from the blood, synovial fluid, and joint-related cells for diagnosis. Moreover, we outlined the potential of modified and unmodified EVs and their combination with biomaterials for OA therapy. Finally, we discuss the deficiencies and put forward the prospects and challenges related to the application of EVs in the field of OA.

Biomaterials and Extracellular Vesicle Delivery: Current Status, Applications and Challenges

In this review, we will discuss the current status of extracellular vesicle (EV) delivery via biopolymeric scaffolds for therapeutic applications and the challenges associated with the development of these functionalized scaffolds. EVs are cell-derived membranous structures and are involved in many physiological processes. Naïve and engineered EVs have much therapeutic potential, but proper delivery systems are required to prevent non-specific and off-target effects. Targeted and site-specific delivery using polymeric scaffolds can address these limitations. EV delivery with scaffolds has shown improvements in tissue remodeling, wound healing, bone healing, immunomodulation, and vascular performance. Thus, EV delivery via biopolymeric scaffolds is becoming an increasingly popular approach to tissue engineering. Although there are many types of natural and synthetic biopolymers, the overarching goal for many tissue engineers is to utilize biopolymers to restore defects and function as well as support host regeneration. Functionalizing biopolymers by incorporating EVs works toward this goal. Throughout this review, we will characterize extracellular vesicles, examine various biopolymers as a vehicle for EV delivery for therapeutic purposes, potential mechanisms by which EVs exert their effects, EV delivery for tissue repair and immunomodulation, and the challenges associated with the use of EVs in scaffolds.