Intrapericardial Exosome Therapy Dampens Cardiac Injury via Activating Foxo3

Exosomes from young plasma stimulate the osteogenic differentiation and prevent osteoporosis via miR-142-5p

Osteoporosis (OP) is a multifactorial metabolic bone disorder commonly observed in the elderly, particularly prevalent in postmenopausal women. However, many conventional anti-osteoporosis drugs have undesirable side effects, limiting their long-term use. Here, we demonstrated that exosomes derived from both young and old healthy human plasma, which exhibited similar morphology, could significantly enhance the proliferation and migration of mesenchymal stem cells (MSCs). Furthermore, treatment with these exosomes increased alkaline phosphatase (ALP) activity, enhanced the mineralization of MSCs, and decreased the number of osteoclasts in vitro. When intravenously injected into rats, these exosomes accumulated in bone tissue. In vivo experiments demonstrated that both types of exosomes had a beneficial effect on osteoporosis by facilitating bone formation and suppressing osteoclast differentiation in an ovariectomized (OVX)-induced osteoporotic rat model. Strikingly, exosomes derived from young healthy human plasma exhibited stronger anti-osteoporosis effect. The miRNA sequencing analysis showed that miR-142-5p expression was significantly higher in the exosomes from young healthy adult plasma compared to in exosomes from older controls. Importantly, miR-142-5p overexpression exerted similar pro-osteogenic effects to those of exosomes from young healthy human plasma, while miR-142-5p downregulation had the opposite effect on osteogenic differentiation of MSCs. The anti-osteoporosis effect of exosomes from young healthy adult plasma were reversed upon miR-142-5p inhibition. In addition, ZFPM2 was a potential target of miR-142-5p involved in osteoporosis. Therefore, our study reveals the potential anti-osteoporosis effects of plasma exosomes and their underlying mechanisms, thereby providing an effective therapeutic strategy for clinical treatment of osteoporosis.

METTL14-mediated m6A methylation of pri-miR-5099 to facilitate cardiomyocyte pyroptosis in myocardial infarction

N6-methyladenosine (m6A) modification is an important mechanism in microRNA processing and maturation. Previous studies show the involvement of pri-miRNA methylation in regulating the occurrence and development of tumor-related diseases. In this study, we investigated the role of its aberrant regulation in cardiac diseases. Myocardial infarction (MI) mouse were established by ligation of the left anterior descending branch of the coronary artery. We showed that the expression of methyltransferase 14 (METTL14) was significantly increased in myocardium of MI mice. We demonstrated that METTL14 methylated the primary transcript miRNA (pri-miR-5099), promoting the recognition by DiGeorge critical region 8 (DGCR8) and the maturation processing of pri-miR-5099. Mature microRNA-5099-3p (miR-5099-3p) inhibited the expression of E74 like ETS transcription factor 1 (ELF1), which transcriptionally regulated pyroptosis factors such as acysteinyl aspartate-specific proteinase 1 (caspase-1) and gasdermin D (GSDMD), ultimately leading to cardiomyocyte pyroptosis. This study reveals that myocardial infarction-induced miR-5099-3p excessive maturation via m6A modification promotes the development and progression of cardiomyocyte pyroptosis.

Beneficial and challenges of exosome application in ischemic heart disease

Cardiovascular diseases are the main cause of death and disability in the clinical setting. Among several pathological conditions, myocardial infarction (MI) is a common clinical finding and happens due to the reduction or complete interruption of blood support. Stem cells and progenitors are valid cell sources with significant potential to alleviate several tissue injuries. Differentiation to mature and functional cells and the release of various growth factors, and cytokines are the main reparative mechanisms by which stem cells mediate their reparative tasks. Exosomes (Exos), a subset of extracellular vesicles (EVs), exhibit great theranostic potential in biomedicine. Along with whole-cell-based therapies, the pre-clinical and clinical application of Exos has been extended in animals and humans with ischemic heart diseases (IHD). Here, in this review article, we aimed to highlight the importance of Exos in IHD and address the mechanism of action by focusing on their regenerative potential.

Immune in myocardial ischemia/reperfusion injury: potential mechanisms and therapeutic strategies

Myocardial infarction (MI), which is characterized by high morbidity and mortality, is a serious threat to human life and health, and timely reperfusion therapy to save ischemic myocardium is currently the most effective intervention. Although reperfusion therapy effectively restores coronary blood flow and maximally limits the infarct size, it triggers additional cell death and tissue damage, which is known as myocardial ischemia/reperfusion injury (MIRI). Multiple immune cells are present in the reperfusion area, executing specific functions and engaging in crosstalk during diverse stages, constituting a complex immune microenvironment involved in tissue repair and regeneration after MIRI. Immunotherapy brings new hope for treating ischemic heart disease by modulating the immune microenvironment. In this paper, we explore the regulatory roles of various immune cells during MIRI and the close relationship between different cell deaths and the immune microenvironment. In addition, we present the current status of research on targeting the immune system to intervene in MIRI, with the expectation of providing a basis for achieving clinical translation.

Impaired ketogenesis in Leydig Cells drives testicular aging

Testicular aging commonly leads to testosterone deficiency and impaired spermatogenesis, yet the underlying mechanisms remain elusive. Here, we show that Leydig cells are particularly vulnerable to aging processes in testis. Single-cell RNA sequencing identifies the expression of Hmgcs2, the gene encoding rate-limiting enzyme of ketogenesis, decreases significantly in Leydig cells from aged mice. Additionally, the concentrations of ketone bodies β-hydroxybutyric acid and acetoacetic acid in young testes are substantially higher than that in serum, but significantly diminish in aged testes. Silencing of Hmgcs2 in young Leydig cells drives cell senescence and accelerated testicular aging. Mechanistically, β-hydroxybutyric acid upregulates the expression of Foxo3a by facilitating histone acetylation, thereby mitigating Leydig cells senescence and promoting testosterone production. Consistently, enhanced ketogenesis by genetic manipulation or oral β-hydroxybutyric acid supplementation alleviates Leydig cells senescence and ameliorates testicular aging in aged mice. These findings highlight defective ketogenesis as a pivotal factor in testicular aging, suggesting potential therapeutic avenues for addressing age-related testicular dysfunction.

The role of exosomes derived from various sources in facilitating the healing of chronic refractory wounds

Chronic refractory wounds (CRWs) represent a common and challenging issue in clinical practice, including diabetic foot ulcers, pressure ulcers, venous ulcers, and arterial ulcers. These wounds significantly impact patients' quality of life and may lead to severe consequences such as amputation. Their treatment requires a comprehensive consideration of both the patient's overall physical condition and the local wound situation. The major challenges in treatment include complex pathogenesis, a long treatment cycle, a high recurrence rate, and heavy economic pressure on the patients. Exosomes represent an emerging therapeutic modality with characteristics such as low immunogenicity, good biostability, and high targeting efficiency in the treatment of diseases. Exosomes derived from different sources exhibit heterogeneity, demonstrating their respective advantages and unique properties in treatment. This article delves into the potential applications and mechanisms of action of exosomes from various sources in the treatment of CRWs, aiming to provide new perspectives and ideas for the management of such wounds.

Lymph Node Exosomes Delivery Attenuates Myocardial Ischemia-Reperfusion Injury via Regulating PTEN-PI3K/Akt Pathway Mediated Myocardiocyte Apoptosis

Background

Ischemia/reperfusion (I/R) injury following acute myocardial infarction (AMI) induces myocardial apoptosis. Exosomes from KLF2-overexpressing endothelial cells (KLF2-EXO) dampened the effects of I/R injury. The intra-lymph node drainage pathway provides an alternative method to study the therapeutic effects of exosomes. In this study, we explored the role of intra-lymph node injection of KLF2-EXO in myocardial I/R injury.

Method and Result

Exosomes were isolated from KLF2-overexpressing mouse coronary endothelial cell supernatant via gradient centrifugation. The mice were subjected to ischemia and reperfusion, and an appropriate dosage of KLF2-EXO was administrated via intra-inguinal lymph node injection. KLF2-EXO attenuated I/R injury and alleviated myocardiocyte apoptosis in heart tissue, and immunofluorescence staining indicated KLF2-EXO could be transferred into the heart. MiRNA-sequencing of KLF2-EXO implicated that miRNA-486-5p (miR-486-5p) was a potent candidate mediator that inhibited myocardiocyte apoptosis, and the miR-486-5p antagomir reversed the effect. Further bioinformatics analysis and confirmation experiments revealed that PTEN functions as a downstream target and that the PTEN- PI3K/Akt pathway participates in the regulation of cardiomyocyte apoptosis.

Conclusion

Our data demonstrated that intra-lymph node injection of KLF2-EXO attenuated myocardial I/R injury in mice by delivering miR-486-5p to target PTEN- PI3K/Akt pathway, which restrained myocardiocyte apoptosis. KLF2-EXO may serve as an alternative therapy for myocardial I/R injury.

Unpacking Exosomes: A Therapeutic Frontier for Cardiac Repair

PURPOSE OF REVIEW

The rising global prevalence of cardiovascular disease is driving the need for innovative biotherapeutics. Recently, exosomes-extracellular vesicles involved in paracrine signaling have shown promise in aiding heart repair associated with cardiovascular conditions. Their therapeutic potential encompasses several beneficial mechanisms, including anti-fibrosis, anti-inflammation, pro-angiogenesis, anti-oxidation, and anti-apoptosis, all contributing to improved cardiac function. This review provides a comprehensive overview of exosomes and highlights the latest research on their effectiveness in addressing current challenges in regenerative cardiac medicine.

RECENT FINDINGS

Current approaches revolve around elucidating and enhancing how different cell types, cargo, and delivery methods impact healing in a pathological cardiovascular environment. The emerging field of therapeutic exosome research is promising for cardiac regeneration due to the beneficial effects of exosomal cargo. The expansion of mechanistic knowledge and the optimization of techniques are required before standard clinical application.

Extracellular vesicles derived from mesenchymal stem cells alleviate renal fibrosis via the miR-99b-5p/mTOR/autophagy axis in diabetic kidney disease

BACKGROUND

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease (ESRD) globally, presenting a significant therapeutic challenge. Extracellular vesicles (EVs) from mesenchymal stem cells (MSCs) have emerged as promising therapeutic agents. This study explored the therapeutic effects and mechanisms of EVs derived from human placental mesenchymal stem cells (hP-MSCs) on DKD.

METHODS

EVs were isolated from cultured hP-MSCs and administered to streptozotocin (STZ)-induced diabetic mice and high glucose-treated glomerular mesangial cells. The therapeutic impact of EVs was assessed through histological analysis and biochemical assays. miR-99b-5p expression in EVs and its role in modulating the mechanistic target of rapamycin (mTOR)/autophagy pathway were examined via western blotting and RT‒qPCR.

RESULTS

Treatment with hP-MSC-derived EVs significantly alleviated renal fibrosis and improved renal function in DKD models. These EVs were enriched with miR-99b-5p, which targeted and inhibited mTOR signaling, thereby increasing autophagic activity and reducing cellular proliferation and extracellular matrix accumulation in renal tissues.

CONCLUSIONS

hP-MSC-derived EVs can mitigate renal injury in DKD by modulating the miR-99b-5p/mTOR/autophagy pathway. These findings suggest a potential cell-free therapeutic strategy for managing DKD.

The landscape of cell regulatory and communication networks in the human dental follicle

Introduction

The dental follicle localizes the surrounding enamel organ and dental papilla of the developing tooth germ during the embryonic stage. It can differentiate and develop to form the periodontal ligament, cementum, and alveolar bone tissues. Postnatally, the dental follicle gradually degenerates, but some parts of the dental follicle remain around the impacted tooth. However, the specific cellular components and the intricate regulatory mechanisms governing the postnatal development and biological function of the dental follicle have not been completely understood.

Methods

We analyzed dental follicles with single-cell RNA sequencing (scRNA-seq) to reveal their cellular constitution molecular signatures by cell cycle analysis, scenic analysis, gene enrichment analysis, and cell communication analysis.

Results

Ten cell clusters were identified with differential characteristics, among which immune and vessel-related cells, as well as a stem cell population, were revealed as the main cell types. Gene regulatory networks (GRNs) were established and defined four regulon modules underlying dental tissue development and microenvironmental regulation, including vascular and immune responses. Cell-cell communication analysis unraveled crosstalk between vascular and immune cell components in orchestrating dental follicle biological activities, potentially based on COLLAGAN-CD44 ligand-receptor pairs, as well as ANGPTL1-ITGA/ITGB ligand-receptor pairs.

Conclusion

We establish a landscape of cell regulatory and communication networks in the human dental follicle, providing mechanistic insights into the cellular regulation and interactions in the complex dental follicle tissue microenvironment.

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.

Mesenchymal stem cells derived exosomes: a new era in cardiac regeneration

Despite significant strides in medical treatments and surgical procedures for cardiovascular diseases, these conditions continue to be a major global health concern. The persistent need for innovative therapeutic approaches to mend damaged heart tissue highlights the complexity and urgency of this medical challenge. In recent years, stem cells have emerged as a promising tool for tissue regeneration, but challenges such as graft rejection and tumor formation have limited their clinical application. Exosomes, extracellular vesicles containing a diverse array of biomolecules, have garnered significant attention for their potential in regenerative medicine. The cardioprotective and reparative properties of mesenchymal stem cell-derived exosomes hold promise for the treatment of heart diseases. These exosomes can modulate various cellular processes, including angiogenesis, apoptosis, and inflammation, thereby enhancing cardiac function. Despite the growing interest, there remains a lack of comprehensive reviews synthesizing the molecular mechanisms, preclinical, and clinical evidence related to the specific role of MSC-derived exosomes in cardiac therapies. This review aims to fill that gap by exploring the potential of MSC-derived exosomes as a therapeutic strategy for cardiac diseases. This review explores the potential of mesenchymal stem cell-derived exosomes as a therapeutic strategy for cardiac diseases. We discuss the molecular mechanisms underlying their cardioprotective effects, summarize preclinical and clinical studies investigating their efficacy, and address the challenges and future perspectives of exosome-based therapies. The collective evidence suggests that MSC-derived exosomes hold promise as a novel and effective therapeutic approach for cardiac diseases.

Two-dimensional cell membrane chromatography guided screening of myocardial protective compounds from Yindan Xinnaotong soft capsule

BACKGROUND

Cell membrane chromatography (CMC) is a biochromatography with a dual function of recognition and separation, offering a distinct advantage in screening bioactive compounds from Chinese medicines (CMs). Yindan Xinnaotong soft capsule (YD), a CM formulation, has been widely utilized in the treatment of cardiovascular disease. However, a comprehensive mapping of the myocardial protective active compounds remains elusive.

PURPOSE

To establish a stable and efficient 2D H9c2/CMC-RPLC-MS system, and to utilize it for screening the active compounds of YD that are associated with myocardial protection.

METHODS

An imidazole-modified silica gel exhibiting high modification efficiency and protein binding capacity was synthesized to enhance the longevity and efficiency of H9c2/CMC. Subsequently, the potentially bioactive compounds of YD were screened by integrating the 2D H9c2/CMC-RPLC-MS system with a high-content component knockout strategy. Additionally, an RNA-seq approach was employed to predict the targets and mechanisms of YD and the active compounds for myocardial protection.

RESULTS

The developed imidazole-modified H9c2/CMC exhibits remarkable selectivity, specificity, stability, and reproducibility. Following three rounds of screening, a total of 24 potential myocardial protective compounds were identified, comprising 8 flavonoids, 8 phenolic acids, 4 saponins, and 4 tanshinones. Bioinformatic analysis utilizing RNA-seq indicated that the FOXO signaling pathway, with FOXO3 identified as a key target, plays a significant role in the cardioprotective effects of YD. Furthermore, all 24 screened compounds exhibit strong binding affinities with FOXO3 evaluated by molecular docking.

CONCLUSION

A highly stable and efficient 2D imidazole-modified H9c2/CMC-RPLC-MS system was developed, allowing for the screening of potentially active compounds from YD. Through the integration of the bioinformatic analysis, the pharmacodynamic foundation of YD for myocardial protection has been comprehensively characterized.

The Potential of Mesenchymal Stem Cell-Derived Exosomes in Cardiac Repair

Cardiovascular diseases (CVDs) are the leading cause of death worldwide, and effectively repairing the heart following myocardial injuries remains a significant challenge. Research has increasingly shown that exosomes derived from mesenchymal stem cells (MSC-Exo) can ameliorate myocardial injuries and improve outcomes after such injuries. The therapeutic benefits of MSC-Exo are largely due to their capacity to deliver specific cargo, including microRNAs and proteins. MSC-Exo can modulate various signaling pathways and provide several beneficial effects, including cytoprotection, inflammation modulation, and angiogenesis promotion to help repair the damaged myocardium. In this review, we summarize the cardioprotective effects of MSC-Exo in myocardial injury, the underlying molecular mechanism involved in the process, and various approaches studied to enhance their efficacy based on recent findings.

Protective effects of Shexiang-Tongxin dropping pill against acute myocardial infarction in rats through inhibition of apoptosis and ERK/MAPK signaling pathways

Acute myocardial infarction (AMI) remains a significant health challenge globally, highlighting the ongoing need for effective treatments. Shexiang-Tongxin dropping pill (STDP) is widely utilized as a therapeutic option for AMI in China and Southeast Asia. However, the intricate mechanisms of action of STDP against AMI remain largely unknown. The pharmacodynamic effects of STDP in treating AMI were evaluated both in vitro and in vivo using human umbilical vein endothelial cell oxygen-glucose deprivation, RAW264.7 cell inflammatory injury, and rat left anterior descending surgery models. The whole transcriptome sequencing was performed to analyze gene expression changes in experimental rat hearts after left anterior descending surgery. An integrative approach combining network pharmacology and sequencing data was used to determine the multi-target and multi-pathway mechanisms underlying the action of STDP against AMI. Molecular docking was conducted to identify the primary anti-AMI ingredients in STDP. STDP treatment significantly resisted AMI in vivo and protected against inflammatory and hypoxic injuries in vitro. It resulted in 63 % (901 of 1430) of genes showing restorative regulation in the AMI disease network, relating to the TGF-β, PI3K, apoptosis, and MAPK pathways. Validation experiments indicated that inhibiting apoptosis and ERK/MAPK pathways by reducing Bax and p-ERK1/2 expression levels in rat hearts may be a crucial mechanism of STDP against AMI. Molecular target prediction indicated that tanshinone IIA, salvianolic acid A, salvianolic acid B, and resibufogenin were the essential pharmacodynamic substances of STDP in AMI treatment. This study sheds light on novel mechanisms by which STDP rebalances the AMI disease network through its multi-target and multi-pathway effects. The findings offer data support for the more precise clinical application of STDP.

Engineered extracellular vesicles as "supply vehicles" to alleviate type 1 diabetes

Recent findings have indicated that the deficiency of inhibitory programmed cell death ligand 1 (PD-L1) and galectin-9 (Gal-9) in pancreatic β-cells is associated with the progression of type 1 diabetes (T1D). This suggests that exogenous PD-L1 and Gal-9 may have promising potential as therapeutics for the treatment of T1D. In light of these reports, a recent work investigated the potential of artificial extracellular vesicles (aEVs) with the presentation of PD-L1 and Gal-9 ligands (PD-L1-Gal-9 aEVs) as a treatment for T1D, with the findings published in Diabetes. Notably, the PD-L1-Gal-9 aEVs demonstrated the capacity to induce apoptosis of T cells and the formation of regulatory T (Treg) cells, thereby maintaining immune tolerance. Furthermore, the in vivo administration of PD-L1-Gal-9 aEVs resulted in a reduction in T cell infiltration in the pancreas, an increase in β-cell integrity protection, a significant decrease in blood glucose levels, and a delay in the progression of T1D. In conclusion, this study proposed an innovative approach to the treatment of T1D progression through the use of immunosuppressive EVs. This highlight provides a comprehensive analysis and discussion of the pivotal findings of this study.

Advances in regulating endothelial-mesenchymal transformation through exosomes

Endothelial-mesenchymal transformation (EndoMT) is the process through which endothelial cells transform into mesenchymal cells, affecting their morphology, gene expression, and function. EndoMT is a potential risk factor for cardiovascular and cerebrovascular diseases, tumor metastasis, and fibrosis. Recent research has highlighted the role of exosomes, a mode of cellular communication, in the regulation of EndoMT. Exosomes from diseased tissues and microenvironments can promote EndoMT, increase endothelial permeability, and compromise the vascular barrier. Conversely, exosomes derived from stem cells or progenitor cells can inhibit the EndoMT process and preserve endothelial function. By modifying exosome membranes or contents, we can harness the advantages of exosomes as carriers, enhancing their targeting and ability to inhibit EndoMT. This review aims to systematically summarize the regulation of EndoMT by exosomes in different disease contexts and provide effective strategies for exosome-based EndoMT intervention.

An infusible biologically active adhesive for chemotherapy-related heart failure in elderly rats

Chemotherapy-induced cardiotoxicity with subsequent heart failure (HF) is a major cause of morbidity and mortality in cancer survivors worldwide. Chemotherapy-induced HF is exceptionally challenging as it generally manifests in patients who are typically not eligible for left ventricular device implantation or heart transplantation. To explore alternative treatment strategies for cancer survivors suffering from chemotherapy-induced HF, we developed a minimally invasive infusible cardiac stromal cell secretomes adhesive (MISA) that could be delivered locally through an endoscope-guided intrapericardial injection. To mimic the typical clinical presentation of chemotherapy-induced HF in elder patients, we established an aged rat model in which restrictive cardiomyopathy with sequential HF was induced via consecutive doxorubicin injections. In vitro, we prove that MISA not only enhanced cardiomyocytes proliferation potency and viability, but also inhibited their apoptosis. In vivo, we prove that MISA improved the ventricular contractility indexes and led to beneficial effects on histological and structural features of restrictive cardiomyopathy via promoting cardiomyocyte proliferation, angiogenesis, and mitochondrial respiration. Additionally, we also evaluated the safety and feasibility of MISA intrapericardial delivery in a healthy porcine model with an intact immune system. In general, our data indicates that MISA has a strong potential for translation into large animal models and ultimately clinical applications for chemotherapy-induced HF prior to the final option of heart transplantation.

The Technique of Permanent Pericardial Catheter in Mice

Intrapericardial delivery offers a route for heart therapies. Mouse heart size and membrane thickness pose catheterization challenges, hampering pericardium-targeted treatments. The objectives were to develop a mouse surgical technique for pericardial catheter insertion and to assess its suitability for intrapericardial delivery, including use with a myocardial ischemia/reperfusion model. We used successful catheter implantation in BALB/cJ and ΔdblGATA1 mice, showcasing intrapericardial delivery with fluorescent beads and eosinophils. We demonstrated a combination of pericardial catheterization with myocardial ischemia/reperfusion model. A reliable catheterization technique, enabling intrapericardial delivery of therapeutic agents in mice provides a valuable tool for studying the pericardial space and mediastinum in basic and translational research.

The negative effects of extracellular vesicles in the immune system

Immunity is a critical self-defense mechanism of the human body, wherein immune cells and immune molecules play a crucial role. Extracellular vesicles (EVs), derived from immune cells or other cells, play a significant role in tumors, autoimmune diseases and other immune-related disorders by serving as carriers and facilitating intercellular communication through the transfer of cargoes. Numerous studies have revealed that EVs can exacerbate disease development by modulating immune responses. Therefore, this paper focuses on the effects of EVs on the number, activity and function of different types of immune cells and the release of immune molecules (such as cytokines, antigens, antibodies, etc) in various diseases, as well as the roles of EVs associated with different types of immune cells in various diseases. We aim to provide a comprehensive review of the negative effects that EVs play in the immune system to provide more ideas and strategies for the management of clinical immune diseases.

Regulatory T cells as a therapeutic target in acute myocardial infarction

Acute myocardial infarction (AMI), mainly triggered by vascular occlusion or thrombosis, is the most prevalent cause of morbidity and mortality among all cardiovascular diseases. The devastating consequences of AMI are further aggravated by the intricate cellular processes involved in inflammation. In the past two decades, many studies have reported that regulatory T cells (Tregs), as the main immunoregulatory cells, play a crucial role in AMI progression. This review offers a comprehensive insight into the intricate relationship between Tregs and AMI development. Moreover, it explores emerging therapeutic strategies that focus on Tregs and their exosomes. Furthermore, we underscore the importance of employing noninvasive in vivo imaging techniques to advance the clinical applications of Tregs-based treatments in AMI. Although further research is essential to fully elucidate the molecular mechanisms underlying the effects of Tregs, therapies tailored to these cells hold immense potential for the treatment of patients with AMI.

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.

Netrin-1-engineered endothelial cell exosomes induce the formation of pre-regenerative niche to accelerate peripheral nerve repair

The formation of vascular niche is pivotal during the early stage of peripheral nerve regeneration. Nevertheless, the mechanisms of vascular niche in the regulation of peripheral nerve repair remain unclear. Netrin-1 (NTN1) was found up-regulated in nerve stump after peripheral nerve injury (PNI). Herein, we demonstrated that NTN1-high endothelial cells (NTN1+ECs) were the critical component of vascular niche, fostering angiogenesis, axon regeneration, and repair-related phenotypes. We also found that NTN1+EC-derived exosomes (NTN1 EC-EXO) were involved in the formation of vascular niche as a critical role. Multi-omics analysis further verified that NTN1 EC-EXO carried a low-level expression of let7a-5p and activated key pathways associated with niche formation including focal adhesion, axon guidance, phosphatidylinositol 3-kinase-AKT, and mammalian target of rapamycin signaling pathway. Together, our study suggested that the construction of a pre-regenerative niche induced by NTN1 EC-EXO could establish a beneficial microenvironment for nerve repair and facilitate functional recovery after PNI.

The chemerin-CMKLR1 axis in keratinocytes impairs innate host defense against cutaneous Staphylococcus aureus infection

The skin is the most common site of Staphylococcus aureus infection, which can lead to various diseases, including invasive and life-threatening infections, through evasion of host defense. However, little is known about the host factors that facilitate the innate immune evasion of S. aureus in the skin. Chemerin, which is abundantly expressed in the skin and can be activated by proteases derived from S. aureus, has both direct bacteria-killing activity and immunomodulatory effects via interactions with its receptor CMKLR1. Here, we demonstrate that a lack of the chemerin/CMKLR1 axis increases the neutrophil-mediated host defense against S. aureus in a mouse model of cutaneous infection, whereas chemerin overexpression, which mimics high levels of chemerin in obese individuals, exacerbates S. aureus cutaneous infection. Mechanistically, we identified keratinocytes that express CMKLR1 as the main target of chemerin to suppress S. aureus-induced IL-33 expression, leading to impaired skin neutrophilia and bacterial clearance. CMKLR1 signaling specifically inhibits IL-33 expression induced by cell wall components but not secreted proteins of S. aureus by inhibiting Akt activation in mouse keratinocytes. Thus, our study revealed that the immunomodulatory effect of the chemerin/CMKLR1 axis mediates innate immune evasion of S. aureus in vivo and likely increases susceptibility to S. aureus infection in obese individuals.

Exosomal let-7a-5p derived from human umbilical cord mesenchymal stem cells alleviates coxsackievirus B3-induced cardiomyocyte ferroptosis via the SMAD2/ZFP36 signal axis

Viral myocarditis (VMC) is one of the most common acquired heart diseases in children and teenagers. However, its pathogenesis is still unclear, and effective treatments are lacking. This study aimed to investigate the regulatory pathway by which exosomes alleviate ferroptosis in cardiomyocytes (CMCs) induced by coxsackievirus B3 (CVB3). CVB3 was utilized for inducing the VMC mouse model and cellular model. Cardiac echocardiography, left ventricular ejection fraction (LVEF), and left ventricular fractional shortening (LVFS) were implemented to assess the cardiac function. In CVB3-induced VMC mice, cardiac insufficiency was observed, as well as the altered levels of ferroptosis-related indicators (glutathione peroxidase 4 (GPX4), glutathione (GSH), and malondialdehyde (MDA)). However, exosomes derived from human umbilical cord mesenchymal stem cells (hucMSCs-exo) could restore the changes caused by CVB3 stimulation. Let-7a-5p was enriched in hucMSCs-exo, and the inhibitory effect of hucMSCs-exolet-7a-5p mimic on CVB3-induced ferroptosis was higher than that of hucMSCs-exomimic NC (NC: negative control). Mothers against decapentaplegic homolog 2 (SMAD2) increased in the VMC group, while the expression of zinc-finger protein 36 (ZFP36) decreased. Let-7a-5p was confirmed to interact with SMAD2 messenger RNA (mRNA), and the SMAD2 protein interacted directly with the ZFP36 protein. Silencing SMAD2 and overexpressing ZFP36 inhibited the expression of ferroptosis-related indicators. Meanwhile, the levels of GPX4, solute carrier family 7, member 11 (SLC7A11), and GSH were lower in the SMAD2 overexpression plasmid (oe-SMAD2)+let-7a-5p mimic group than in the oe-NC+let-7a-5p mimic group, while those of MDA, reactive oxygen species (ROS), and Fe2+ increased. In conclusion, these data showed that ferroptosis could be regulated by mediating SMAD2 expression. Exo-let-7a-5p derived from hucMSCs could mediate SMAD2 to promote the expression of ZFP36, which further inhibited the ferroptosis of CMCs to alleviate CVB3-induced VMC.

The crosstalk between exosomes and ferroptosis: a review

Exosomes are a subtype of extracellular vesicles composed of bioactive molecules, including nucleic acids, proteins, and lipids. Exosomes are generated by the fusion of intracellular multivesicular bodies (MVBs) with the cell membrane and subsequently released into the extracellular space to participate in intercellular communication and diverse biological processes within target cells. As a crucial mediator, exosomes have been implicated in regulating ferroptosis-an iron-dependent programmed cell death characterized by lipid peroxide accumulation induced by reactive oxygen species. The involvement of exosomes in iron, lipid, and amino acid metabolism contributes to their regulatory role in specific mechanisms underlying how exosomes modulate ferroptosis, which remains incompletely understood, and some related studies are still preliminary. Therefore, targeting the regulation of ferroptosis by exosomes holds promise for future clinical treatment strategies across various diseases. This review aims to provide insights into the pathophysiology and mechanisms governing the interaction between exosomes and ferroptosis and their implications in disease development and treatment to serve as a reference for further research.

Targeted drug delivery of engineered mesenchymal stem/stromal-cell-derived exosomes in cardiovascular disease: recent trends and future perspectives

In recent years, stem cells and their secretomes, notably exosomes, have received considerable attention in biomedical applications. Exosomes are cellular secretomes used for intercellular communication. They perform the function of intercellular messengers by facilitating the transport of proteins, lipids, nucleic acids, and therapeutic substances. Their biocompatibility, minimal immunogenicity, targetability, stability, and engineerable characteristics have additionally led to their application as drug delivery vehicles. The therapeutic efficacy of exosomes can be improved through surface modification employing functional molecules, including aptamers, antibodies, and peptides. Given their potential as targeted delivery vehicles to enhance the efficiency of treatment while minimizing adverse effects, exosomes exhibit considerable promise. Stem cells are considered advantageous sources of exosomes due to their distinctive characteristics, including regenerative and self-renewal capabilities, which make them well-suited for transplantation into injured tissues, hence promoting tissue regeneration. However, there are notable obstacles that need to be addressed, including immune rejection and ethical problems. Exosomes produced from stem cells have been thoroughly studied as a cell-free strategy that avoids many of the difficulties involved with cell-based therapy for tissue regeneration and cancer treatment. This review provides an in-depth summary and analysis of the existing knowledge regarding exosomes, including their engineering and cardiovascular disease (CVD) treatment applications.

Role of Treg cell subsets in cardiovascular disease pathogenesis and potential therapeutic targets

In the genesis and progression of cardiovascular diseases involving both innate and adaptive immune responses, inflammation plays a pivotal and dual role. Studies in experimental animals indicate that certain immune responses are protective, while others exacerbate the disease. T-helper (Th) 1 cell immune responses are recognized as key drivers of inflammatory progression in cardiovascular diseases. Consequently, the CD4+CD25+FOXP3+ regulatory T cells (Tregs) are gaining increasing attention for their roles in inflammation and immune regulation. Given the critical role of Tregs in maintaining immune-inflammatory balance and homeostasis, abnormalities in their generation or function might lead to aberrant immune responses, thereby initiating pathological changes. Numerous preclinical studies and clinical trials have unveiled the central role of Tregs in cardiovascular diseases, such as atherosclerosis. Here, we review the roles and mechanisms of Treg subsets in cardiovascular conditions like atherosclerosis, hypertension, myocardial infarction and remodeling, myocarditis, dilated cardiomyopathy, and heart failure. While the precise molecular mechanisms of Tregs in cardiac protection remain elusive, therapeutic strategies targeting Tregs present a promising new direction for the prevention and treatment of cardiovascular diseases.

Anticancer Therapy Targeting Cancer-Derived Extracellular Vesicles

Extracellular vesicles (EVs) are natural lipid nanoparticles secreted by most types of cells. In malignant cancer, EVs derived from cancer cells contribute to its progression and metastasis by facilitating tumor growth and invasion, interfering with anticancer immunity, and establishing premetastasis niches in distant organs. In recent years, multiple strategies targeting cancer-derived EVs have been proposed to improve cancer patient outcomes, including inhibiting EV generation, disrupting EVs during trafficking, and blocking EV uptake by recipient cells. Developments in EV engineering also show promising results in harnessing cancer-derived EVs as anticancer agents. Here, we summarize the current understanding of the origin and functions of cancer-derived EVs and review the recent progress in anticancer therapy targeting these EVs.

Stem cell-based therapy in cardiac repair after myocardial infarction: Promise, challenges, and future directions

Stem cells represent an attractive resource for cardiac regeneration. However, the survival and function of transplanted stem cells is poor and remains a major challenge for the development of effective therapies. As two main cell types currently under investigation in heart repair, mesenchymal stromal cells (MSCs) indirectly support endogenous regenerative capacities after transplantation, while induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) functionally integrate into the damaged myocardium and directly contribute to the restoration of its pump function. These two cell types are exposed to a common microenvironment with many stressors in ischemic heart tissue. This review summarizes the research progress on the mechanisms and challenges of MSCs and iPSC-CMs in post-MI heart repair, introduces several randomized clinical trials with 3D-mapping-guided cell therapy, and outlines recent findings related to the factors that affect the survival and function of stem cells. We also discuss the future directions for optimization such as biomaterial utilization, cell combinations, and intravenous injection of engineered nucleus-free MSCs.

Unraveling the Signaling Dynamics of Small Extracellular Vesicles in Cardiac Diseases

Effective intercellular communication is essential for cellular and tissue balance maintenance and response to challenges. Cellular communication methods involve direct cell contact or the release of biological molecules to cover short and long distances. However, a recent discovery in this communication network is the involvement of extracellular vesicles that host biological contents such as proteins, nucleic acids, and lipids, influencing neighboring cells. These extracellular vesicles are found in body fluids; thus, they are considered as potential disease biomarkers. Cardiovascular diseases are significant contributors to global morbidity and mortality, encompassing conditions such as ischemic heart disease, cardiomyopathies, electrical heart diseases, and heart failure. Recent studies reveal the release of extracellular vesicles by cardiovascular cells, influencing normal cardiac function and structure. However, under pathological conditions, extracellular vesicles composition changes, contributing to the development of cardiovascular diseases. Investigating the loading of molecular cargo in these extracellular vesicles is essential for understanding their role in disease development. This review consolidates the latest insights into the role of extracellular vesicles in diagnosis and prognosis of cardiovascular diseases, exploring the potential applications of extracellular vesicles in personalized therapies, shedding light on the evolving landscape of cardiovascular medicine.

A Biomimetic Cardiac Fibrosis-on-a-Chip as a Visible Disease Model for Evaluating Mesenchymal Stem Cell-Derived Exosome Therapy

Cardiac fibrosis acts as a serious worldwide health issue due to its prevalence in numerous forms of cardiac disease and its essential link to cardiac failure. Considering the efficiency of stem cell therapy for cardiac fibrosis, great efforts have been dedicated to developing accurate models for investigating their underlying therapeutic mechanisms. Herein we present an elaborate biomimetic cardiac fibrosis-on-a-chip based on Janus structural color film (SCF) to provide microphysiological visuals for stem cell therapeutic studies. By coculturing cardiomyocytes (CMs) and cardiac fibroblasts (FBs) on Janus SCF with fibrosis induction, the chip can recreate physiological intercellular crosstalk within the fibrotic microenvironment, elucidating the physiological alterations of fibrotic hearts. In particular, the Janus structural color film possesses superior perceptual capabilities for capturing and responding to a weak cardiac force, demonstrating synchronized structural color shifts. Based on these features, we have not only explored the dynamic relationship between color mapping and the evaluated disease phenotype but also demonstrated the self-reporting capacity of the cardiac fibrosis-on-a-chip for the assessment of mesenchymal stem cell-derived exosome therapy. These features suggest that such a chip can potentially facilitate the evolution of precision medicine strategies and create a protocol for preclinical cardiac drug screening.

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.

The therapeutic efficacy and clinical translation of mesenchymal stem cell-derived exosomes in cardiovascular diseases

Exosomes, mainly derived from mesenchymal stem cells, provide a good reference for cardiac function repair and clinical application in cardiac and vascular diseases by regulating cardiomyocyte viability, inflammatory levels, angiogenesis, and ventricular remodeling after a heart injury. This review presents the cardioprotective efficacy of mesenchymal stem cell-originated exosomes and explores the underlying molecular mechanisms. Furthermore, we expound on several efficient approaches to transporting exosomes into the heart in clinical application and comment on the advantages and disadvantages of each method.

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.

Advances in the study of exosomes derived from mesenchymal stem cells and cardiac cells for the treatment of myocardial infarction

Acute myocardial infarction has long been the leading cause of death in coronary heart disease, which is characterized by irreversible cardiomyocyte death and restricted blood supply. Conventional reperfusion therapy can further aggravate myocardial injury. Stem cell therapy, especially with mesenchymal stem cells (MSCs), has emerged as a promising approach to promote cardiac repair and improve cardiac function. MSCs may induce these effects by secreting exosomes containing therapeutically active RNA, proteins and lipids. Notably, normal cardiac function depends on intracardiac paracrine signaling via exosomes, and exosomes secreted by cardiac cells can partially reflect changes in the heart during disease, so analyzing these vesicles may provide valuable insights into the pathology of myocardial infarction as well as guide the development of new treatments. The present review examines how exosomes produced by MSCs and cardiac cells may influence injury after myocardial infarction and serve as therapies against such injury. Video Abstract.

Therapeutic Potential of EVs: Targeting Cardiovascular Diseases

Due to their different biological functions, extracellular vesicles (EVs) have great potential from a therapeutic point of view. They are released by all cell types, carrying and delivering different kinds of biologically functional cargo. Under pathological events, cells can increase their secretion of EVs and can release different amounts of cargo, thus making EVs great biomarkers as indicators of pathological progression. Moreover, EVs are also known to be able to transport and deliver cargo to different recipient cells, having an important role in cellular communication. Interestingly, EVs have recently been explored as biological alternatives for the delivery of therapeutics, being considered natural drug delivery carriers. Because cardiovascular disorders (CVDs) are the leading cause of death worldwide, in this review, we will discuss the up-to-date knowledge regarding the biophysical properties and biological components of EVs, focusing on myocardial infarction, diabetic cardiomyopathy, and sepsis-induced cardiomyopathy, three very different types of CVDs.

Intrapericardial long non-coding RNA-Tcf21 antisense RNA inducing demethylation administration promotes cardiac repair

AIMS

Epicardium and epicardium-derived cells are critical players in myocardial fibrosis. Mesenchymal stem cell-derived extracellular vesicles (EVs) have been studied for cardiac repair to improve cardiac remodelling, but the actual mechanisms remain elusive. The aim of this study is to investigate the mechanisms of EV therapy for improving cardiac remodelling and develop a promising treatment addressing myocardial fibrosis.

METHODS AND RESULTS

Extracellular vesicles were intrapericardially injected for mice myocardial infarction treatment. RNA-seq, in vitro gain- and loss-of-function experiments, and in vivo studies were performed to identify targets that can be used for myocardial fibrosis treatment. Afterward, a lipid nanoparticle-based long non-coding RNA (lncRNA) therapy was prepared for mouse and porcine models of myocardial infarction treatment. Intrapericardial injection of EVs improved adverse myocardial remodelling in mouse models of myocardial infarction. Mechanistically, Tcf21 was identified as a potential target to improve cardiac remodelling. Loss of Tcf21 function in epicardium-derived cells caused increased myofibroblast differentiation, whereas forced Tcf21 overexpression suppressed transforming growth factor-β signalling and myofibroblast differentiation. LncRNA-Tcf21 antisense RNA inducing demethylation (TARID) that enriched in EVs was identified to up-regulate Tcf21 expression. Formulated lncRNA-TARID-laden lipid nanoparticles up-regulated Tcf21 expression in epicardium-derived cells and improved cardiac function and histology in mouse and porcine models of myocardial infarction.

CONCLUSION

This study identified Tcf21 as a critical target for improving cardiac fibrosis. Up-regulating Tcf21 by using lncRNA-TARID-laden lipid nanoparticles could be a promising way to treat myocardial fibrosis. This study established novel mechanisms underlying EV therapy for improving adverse remodelling and proposed a lncRNA therapy for cardiac fibrosis.

Mesenchymal stem cell-derived exosomes in cardiovascular and cerebrovascular diseases: From mechanisms to therapy

Cardiovascular and cerebrovascular diseases (CVDs) remain an intractable problem and have high morbidity and mortality worldwide, as well as substantial health and economic burdens, representing an urgent clinical need. In recent years, the focus of research has shifted from the use of mesenchymal stem cells (MSCs) for transplantation to the use of their secretory exosomes (MSC-exosomes) for the treatment of numerous CVDs, including atherosclerosis, myocardial infarction (MI), heart failure (HF), ischemia/reperfusion (I/R), aneurysm, and stroke. MSCs are pluripotent stem cells with multiple differentiation pathways that exert pleiotropic effects by producing soluble factors, the most effective components of which are exosomes. MSC-exosomes are considered to be an excellent and promising cell-free therapy for CVDs due to their higher circulating stability, improved biocompatibility, reduced toxicity, and immunogenicity. In addition, exosomes play critical roles in repairing CVDs by inhibiting apoptosis, regulating inflammation, ameliorating cardiac remodeling, and promoting angiogenesis. Herein, we describe knowledge about the biological characteristics of MSC-exosomes, investigate the mechanism by which MSC-exosomes mediate therapeutic repair, and summarize recent advances in the efficacy of MSC-exosomes in CVDs, with a view toward future clinical applications.

Comparison of extruded cell nanovesicles and exosomes in their molecular cargos and regenerative potentials

Extracellular vesicles (EVs) generated from mesenchymal stem cells (MSCs) play an essential role in modulating cell-cell communication and tissue regeneration. The clinical translation of EVs is constrained by the poor yield of EVs. Extrusion has recently become an effective technique for producing a large scale of nanovesicles (NVs). In this study, we systematically compared MSC NVs (from extrusion) and EVs (from natural secretion). Proteomics and RNA sequencing data revealed that NVs resemble MSCs more closely than EVs. Additionally, microRNAs in NVs are related to cardiac repair, fibrosis repression, and angiogenesis. Lastly, intravenous delivery of MSC NVs improved heart repair and cardiac function in a mouse model of myocardial infarction.

Electronic Supplementary Material

Supplementary material (Figs. S1-S4) is available in the online version of this article at 10.1007/s12274-023-5374-3.

Neonatal Plasma Exosomes Contribute to Endothelial Cell-Mediated Angiogenesis and Cardiac Repair after Acute Myocardial Infarction

Acute myocardial infarction (AMI) accompanied by cardiac remodeling still lacks effective treatment to date. Accumulated evidences suggest that exosomes from various sources play a cardioprotective and regenerative role in heart repair, but their effects and mechanisms remain intricate. Here, we found that intramyocardial delivery of plasma exosomes from neonatal mice (npEXO) could help to repair the adult heart in structure and function after AMI. In-depth proteome and single-cell transcriptome analyses suggested that npEXO ligands were majorly received by cardiac endothelial cells (ECs), and npEXO-mediated angiogenesis might serve as a pivotal reason to ameliorate the infarcted adult heart. We then innovatively constructed systematical communication networks among exosomal ligands and cardiac ECs and the final 48 ligand-receptor pairs contained 28 npEXO ligands (including the angiogenic factors, Clu and Hspg2), which mainly mediated the pro-angiogenic effect of npEXO by recognizing five cardiac EC receptors (Kdr, Scarb1, Cd36, etc.). Together, the proposed ligand-receptor network in our study might provide inspiration for rebuilding the vascular network and cardiac regeneration post-MI.

Mesenchymal Stem Cells and Their Exocytotic Vesicles

Mesenchymal stem cells (MSCs), as a kind of pluripotent stem cells, have attracted much attention in orthopedic diseases, geriatric diseases, metabolic diseases, and sports functions due to their osteogenic potential, chondrogenic differentiation ability, and adipocyte differentiation. Anti-inflammation, anti-fibrosis, angiogenesis promotion, neurogenesis, immune regulation, and secreted growth factors, proteases, hormones, cytokines, and chemokines of MSCs have been widely studied in liver and kidney diseases, cardiovascular and cerebrovascular diseases. In recent years, many studies have shown that the extracellular vesicles of MSCs have similar functions to MSCs transplantation in all the above aspects. Here we review the research progress of MSCs and their exocrine vesicles in recent years.