Targeted delivery of extracellular vesicles in heart injury

Cardiac resident macrophages: The core of cardiac immune homeostasis

Cardiac resident macrophages (CRMs) are essential in maintaining the balance of the immune homeostasis in the heart. One of the main factors in the progression of cardiovascular diseases, such as myocarditis, myocardial infarction(MI), and heart failure(HF), is the imbalance in the regulatory mechanisms of CRMs. Recent studies have reported novel heterogeneity and spatiotemporal complexity of CRMs, and their role in maintaining cardiac immune homeostasis and treating cardiovascular diseases. In this review, we focus on the functions of CRMs, including immune surveillance, immune phagocytosis, and immune metabolism, and explore the impact of CRM's homeostasis imbalance on cardiac injury and cardiac repair. We also discuss the therapeutic approaches linked to CRMs. The immunomodulatory strategies targeting CRMs may be a therapeutic approach for the treatment of cardiovascular disease.

Plasmonic nano-bowls for monitoring intra-membrane changes in liposomes, and DNA-based nanocarriers in suspension

Programmable nanoscale carriers, such as liposomes and DNA, are readily being explored for personalized medicine or disease prediction and diagnostics. The characterization of these nanocarriers is limited and challenging due to their complex chemical composition. Here, we demonstrate the utilization of surface-enhanced Raman spectroscopy (SERS), which provides a unique molecular fingerprint of the analytes while reducing the detection limit. In this paper, we utilize a silver coated nano-bowl shaped polydimethylsiloxane (PDMS) SERS substrate. The utilization of nano-bowl surface topology enabled the passive trapping of particles by reducing mobility, which results in reproducible SERS signal enhancement. The biological nanoparticles' dwell time in the nano-trap was in the order of minutes, thus allowing SERS spectra to remain in their natural aqueous medium without the need for drying. First, the geometry of the nano-traps was designed considering nanosized bioparticles of 50-150 nm diameter. Further, the systematic investigation of maximum SERS activity was performed using rhodamine 6 G as a probe molecule. The potential of the optimized SERS nano-bowl is shown through distinct spectral features following surface- (polyethylene glycol) and bilayer- (cholesterol) modification of empty liposomes of around 140 nm diameter. Apart from liposomes, the characterization of the highly crosslinked DNA specimens of only 60 nm in diameter was performed. The modification of DNA gel by liposome coating exhibited unique signatures for nitrogenous bases, sugar, and phosphate groups. Further, the unique sensitivity of the proposed SERS substrate displayed distinct spectral signatures for DNA micelles and drug-loaded DNA micelles, carrying valuable information to monitor drug release. In conclusion, the findings of the spectral signatures of a wide range of molecular complexes and chemical morphology of intra-membranes in their natural state highlight the possibilities of using SERS as a sensitive and instantaneous characterization alternative.

M2 macrophage‑derived exosomes alleviate KCa3.1 channel expression in rapidly paced HL‑1 myocytes via the NF‑κB (p65)/STAT3 signaling pathway

The present study was designed to explore the role of M2 macrophage‑derived exosomes (M2‑exos) on the KCa3.1 channel in a cellular atrial fibrillation (AF) model using rapidly paced HL‑1 myocytes. M2 macrophages and M2‑exos were isolated and identified. MicroRNA (miR)‑146a‑5p levels in M2 macrophages and M2‑exos were quantified using reverse transcription‑quantitative PCR (RT‑qPCR). HL‑1 myocytes were randomly divided into six groups: Control group, pacing group, pacing + coculture group (pacing HL‑1 cells cocultured with M2‑exos), pacing + mimic‑miR‑146a‑5p group, pacing + NC‑miR‑146a‑5p group and pacing + pyrrolidine dithiocarbamate (PDTC; a special blocker of the NF‑κB signaling pathway) group. Transmission electron microscopy, nanoparticle tracking analysis, western blotting, RT‑qPCR and immunohistochemistry were performed in the present study. A whole‑cell clamp was also applied to record the current density of KCa3.1 and action potential duration (APD) in each group. The results revealed that miR‑146a‑5p was highly expressed in both M2 macrophages and M2‑exos. Pacing HL‑1 cells led to a shorter APD, an increased KCa3.1 current density and higher protein levels of KCa3.1, phosphorylated (p‑)NF‑κB p65, p‑STAT3 and IL‑1β compared with the control group. M2‑exos, miR‑146a‑5p‑mimic and PDTC both reduced the protein expression of KCa3.1, p‑NF‑κB p65, p‑STAT3 and IL‑1β and the current density of KCa3.1, resulting in a longer APD in the pacing HL‑1 cells. In conclusion, M2‑exos and their cargo, which comprised miR‑146a‑5p, decreased KCa3.1 expression and IL‑1β secretion in pacing HL‑1 cells via the NF‑κB/STAT3 signaling pathway, limiting the shorter APD caused by rapid pacing.

Exploring Cutting-Edge Approaches to Potentiate Mesenchymal Stem Cell and Exosome Therapy for Myocardial Infarction

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

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.

Advances in the study of exosomes in cardiovascular diseases

BACKGROUND

Cardiovascular disease (CVD) has been the leading cause of death worldwide for many years. In recent years, exosomes have gained extensive attention in the cardiovascular system due to their excellent biocompatibility. Studies have extensively researched miRNAs in exosomes and found that they play critical roles in various physiological and pathological processes in the cardiovascular system. These processes include promoting or inhibiting inflammatory responses, promoting angiogenesis, participating in cell proliferation and migration, and promoting pathological progression such as fibrosis.

AIM OF REVIEW

This systematic review examines the role of exosomes in various cardiovascular diseases such as atherosclerosis, myocardial infarction, ischemia-reperfusion injury, heart failure and cardiomyopathy. It also presents the latest treatment and prevention methods utilizing exosomes. The study aims to provide new insights and approaches for preventing and treating cardiovascular diseases by exploring the relationship between exosomes and these conditions. Furthermore, the review emphasizes the potential clinical use of exosomes as biomarkers for diagnosing cardiovascular diseases.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Exosomes are nanoscale vesicles surrounded by lipid bilayers that are secreted by most cells in the body. They are heterogeneous, varying in size and composition, with a diameter typically ranging from 40 to 160 nm. Exosomes serve as a means of information communication between cells, carrying various biologically active substances, including lipids, proteins, and small RNAs such as miRNAs and lncRNAs. As a result, they participate in both physiological and pathological processes within the body.

Delivery of SAV-siRNA via Exosomes from Adipose-Derived Stem Cells for the Treatment of Myocardial Infarction

BACKGROUND

Myocardial infarction (MI) leads to cardiomyocyte death, poor cardiac remodeling, and heart failure, making it a major cause of mortality and morbidity. To restore cardiac pumping function, induction of cardiomyocyte regeneration has become a focus of academic interest. The Hippo pathway is known to regulate cardiomyocyte proliferation and heart size, and its inactivation allows adult cardiomyocytes to re-enter the cell cycle.

METHODS

In this study, we investigated whether exosomes from adipose-derived stem cells (ADSCs) could effectively transfer siRNA for the Hippo pathway regulator Salvador (SAV) into cardiomyocytes to induce cardiomyocyte regeneration in a mouse model of MI.

RESULTS

Our results showed that exosomes loaded with SAV-siRNA effectively transferred siRNA into cardiomyocytes and induced cardiomyocyte re-entry into the cell cycle, while retaining the previously demonstrated therapeutic efficacy of ADSC-derived exosomes to improve post-infarction cardiac function through anti-fibrotic, pro-angiogenic, and other effects.

CONCLUSIONS

Our findings suggest that siRNA delivery via ADSC-derived exosomes may be a promising approach for the treatment of MI.

Extracellular vesicles in cardiovascular diseases: From pathophysiology to diagnosis and therapy

Extracellular vesicles (EVs), encompassing exosomes, microvesicles (MVs), and apoptotic bodies (ABs), are cell-derived heterogeneous nanoparticles with a pivotal role in intercellular communication. EVs are enclosed by a lipid-bilayer membrane to escape enzymatic degradation. EVs contain various functional molecules (e.g., nucleic acids, proteins, lipids and metabolites) which can be transferred from donor cells to recipient cells. EVs provide many advantages including accessibility, modifiability and easy storage, stability, biocompatibility, heterogeneity and they readily penetrate through biological barriers, making EVs ideal and promising candidates for diagnosis/prognosis biomarkers and therapeutic tools. Recently, EVs were implicated in both physiological and pathophysiological settings of cardiovascular system through regulation of cell-cell communication. Numerous studies have reported a role for EVs in the pathophysiological progression of cardiovascular diseases (CVDs) and have evaluated the utility of EVs for the diagnosis/prognosis and therapeutics of CVDs. In this review, we summarize the biology of EVs, evaluate the perceived biological function of EVs in different CVDs along with a consideration of recent progress for the application of EVs in diagnosis/prognosis and therapies of CVDs.

Both extracellular vesicles from helicobacter pylori-infected cells and helicobacter pylori outer membrane vesicles are involved in gastric/extragastric diseases

Bacterial-derived extracellular vesicles (EVs) have emerged as crucial mediators in the cross-talk between hosts and pathogens, playing a significant role in infectious diseases and cancers. Among these pathogens, Helicobacter pylori (H. pylori) is a particularly important bacterium implicated in various gastrointestinal disorders, gastric cancers, and systemic illnesses. H. pylori achieves these effects by stimulating host cells to secrete EVs and generating internal outer membrane vesicles (OMVs). The EVs derived from H. pylori-infected host cells modulate inflammatory signaling pathways, thereby affecting cell proliferation, apoptosis, cytokine release, immune cell modification, and endothelial dysfunction, as well as disrupting cellular junctional structures and inducing cytoskeletal reorganization. In addition, OMVs isolated from H. pylori play a pivotal role in shaping subsequent immunopathological responses. These vesicles incite both inflammatory and immunosuppressive reactions within the host environment, facilitating pathogen evasion of host defenses and invasion of host cells. Despite this growing understanding, research involving H. pylori-derived EVs remains in its early stages across different domains. In this comprehensive review, we present recent advancements elucidating the contributions of EV components, such as non-coding RNAs (ncRNAs) and proteins, to the pathogenesis of gastric and extragastric diseases. Furthermore, we highlight their potential utility as biomarkers, therapeutic targets, and vehicles for targeted delivery.

Challenges and future scope of exosomes in the treatment of cardiovascular diseases

Exosomes are nanosized vesicles that carry biologically diverse molecules for intercellular communication. Researchers have been trying to engineer exosomes for therapeutic purposes by using different approaches to deliver biologically active molecules to the various target cells efficiently. Recent technological advances may allow the biodistribution and pharmacokinetics of exosomes to be modified to meet scientific needs with respect to specific diseases. However, it is essential to determine an exosome's optimal dosage and potential side effects before its clinical use. Significant breakthroughs have been made in recent decades concerning exosome labelling and imaging techniques. These tools provide in situ monitoring of exosome biodistribution and pharmacokinetics and pinpoint targetability. However, because exosomes are nanometres in size and vary significantly in contents, a deeper understanding is required to ensure accurate monitoring before they can be applied in clinical settings. Different research groups have established different approaches to elucidate the roles of exosomes and visualize their spatial properties. This review covers current and emerging strategies for in vivo and in vitro exosome imaging and tracking for potential studies.

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 Extracellular Vesicles: Emerging Therapeutic Strategies for Translational Applications

Extracellular vesicles (EVs) are small, membrane-bound vesicles used by cells to deliver biological cargo such as proteins, mRNA, and other biomolecules from one cell to another, thus inducing a specific response in the target cell and are a powerful method of cell to cell and organ to organ communication, especially during the pathogenesis of human disease. Thus, EVs may be utilized as prognostic and diagnostic biomarkers, but they also hold therapeutic potential just as mesenchymal stem cells have been used in therapeutics. However, unmodified EVs exhibit poor targeting efficacy, leading to the necessity of engineered EVS. To highlight the advantages and therapeutic promises of engineered EVs, in this review, we summarized the research progress on engineered EVs in the past ten years, especially in the past five years, and highlighted their potential applications in therapeutic development for human diseases. Compared to the existing stem cell-derived EV-based therapeutic strategies, engineered EVs show greater promise in clinical applications: First, engineered EVs mediate good targeting efficacy by exhibiting a targeting peptide that allows them to specifically target a specific organ or even cell type, thus avoiding accumulation in undesired locations and increasing the potency of the treatment. Second, engineered EVs can be artificially pre-loaded with any necessary biomolecular cargo or even therapeutic drugs to treat a variety of human diseases such as cancers, neurological diseases, and cardiovascular ailments. Further research is necessary to improve logistical challenges in large-scale engineered EV manufacturing, but current developments in engineered EVs prove promising to greatly improve therapeutic treatment for traditionally difficult to treat diseases.

Exosome-bearing hydrogels and cardiac tissue regeneration

BACKGROUND

In recent years, cardiovascular disease in particular myocardial infarction (MI) has become the predominant cause of human disability and mortality in the clinical setting. The restricted capacity of adult cardiomyocytes to proliferate and restore the function of infarcted sites is a challenging issue after the occurrence of MI. The application of stem cells and byproducts such as exosomes (Exos) has paved the way for the alleviation of cardiac tissue injury along with conventional medications in clinics. However, the short lifespan and activation of alloreactive immune cells in response to Exos and stem cells are the main issues in patients with MI. Therefore, there is an urgent demand to develop therapeutic approaches with minimum invasion for the restoration of cardiac function.

MAIN BODY

Here, we focused on recent data associated with the application of Exo-loaded hydrogels in ischemic cardiac tissue. Whether and how the advances in tissue engineering modalities have increased the efficiency of whole-based and byproducts (Exos) therapies under ischemic conditions. The integration of nanotechnology and nanobiology for designing novel smart biomaterials with therapeutic outcomes was highlighted.

CONCLUSION

Hydrogels can provide suitable platforms for the transfer of Exos, small molecules, drugs, and other bioactive factors for direct injection into the damaged myocardium. Future studies should focus on the improvement of physicochemical properties of Exo-bearing hydrogel to translate for the standard treatment options.

Targeted heart repair by Tβ4-loaded cardiac-resident macrophage-derived extracellular vesicles modified with monocyte membranes

Recent studies have demonstrated the critical role of cardiac-resident macrophages (cMacs) in the maintenance of physiological homeostasis. However, recruitment of circulating monocyte-derived macrophages decreases cMac levels post-myocardial infarction (MI). Transplanting cMacs is not an ideal option due to their low survival rates and the risk of immunological rejection. However, extracellular vesicle therapy has the potential to provide a feasible and safe alternative for cardiac repair. In this study, cell membrane-modified extracellular vesicles (MmEVs) were developed for heart repair by modifying cMac-derived extracellular vesicles (mEVs) with monocyte membranes, resulting in immune evasion and sequential targeted localization to damaged regions through expression of CD47 on MmEVs and strong affinity between monocyte membrane proteins and CCL2. Additionally, to fully exploit the potential clinical application of MmEVs and achieve a better curative effect, thymosin β4 (Tβ4) was loaded into the nanoparticles, resulting in Tβ4-MmEVs. In vitro experiments indicated that both the MmEVs and Tβ4-MmEVs promoted cardiomyocyte proliferation and endothelial cell migration. Animal experiments suggested that MI mice treated with MmEVs and Tβ4-MmEVs exhibited reduced myocardial fibrosis and increased vascular density compared to the control group. Thus, we posit that these targeted nanoparticles hold significant potential for MI adjuvant therapy and may open new avenues for cardiac repair and regeneration. STATEMENT OF SIGNIFICANCE: Extracellular vesicles (EVs) derived from bioactive parent cell sources involved in pathological and repair processes for cardiovascular disease have emerged as a compelling strategy for regenerative therapy. In this study, we constructed monocyte membrane-modified extracellular vesicles loaded with a drug (Tβ4-MmEVs) for heart repair that exhibit extraordinary abilities of immune evasion and sequential localization to damaged regions owing to the presence of CD47 and the strong affinity between monocytes and damaged cardiomyocytes and endothelial cells. The bioactivities of Tβ4-MmEVs on enhancing cardiomyocyte and endothelial cell proliferation were validated both in vitro and in vivo. Effective development and implementation of therapeutically membrane-modified nanoparticles from homologous origins can provide a reference for adjuvant therapy in clinical MI management.

Injectable photocurable Janus hydrogel delivering hiPSC cardiomyocyte-derived exosome for post-heart surgery adhesion reduction

Postsurgical pericardial adhesions pose increased risks of sequelae, prolonged reoperation time, and reduced visibility in the surgical field. Here, we introduce an injectable Janus hydrogel, which exhibits asymmetric adhesiveness properties after photocrosslinking, sustained delivering induced pluripotent stem cell-derived cardiomyocyte exosomes (iCM-EXOs) for post-heart surgery adhesion reduction. Our findings reveal that iCM-EXOs effectively attenuate oxidative stress in hydrogen peroxide-treated primary cardiomyocytes by inhibiting the activation of the transcription factor nuclear factor erythroid 2-related factor 2. Notably, in rat cardiac postsurgery models, the Janus hydrogels loaded with iCM-EXOs demonstrate dual functionality, acting as antioxidants and antipericardial adhesion agents. These hydrogels effectively protect iCM-EXOs from GATA6+ cavity macrophage clearance by inhibiting the recruitment of macrophages from the thoracic cavity. These results highlight the promising potential of iCM-EXO-laden Janus hydrogels for clinical safety and efficacy validation in trials involving heart surgery patients, with the ultimate goal of routine administration during open-heart surgeries.

Biodelivery of therapeutic extracellular vesicles: should mononuclear phagocytes always be feared?

At present, extracellular vesicles (EVs) are considered key candidates for cell-free therapies, including treatment of allergic and autoimmune diseases. However, their therapeutic effectiveness, dependent on proper targeting to the desired cells, is significantly limited due to the reduced bioavailability resulting from their rapid clearance by the cells of the mononuclear phagocyte system (MPS). Thus, developing strategies to avoid EV elimination is essential when applying them in clinical practice. On the other hand, malfunctioning MPS contributes to various immune-related pathologies. Therapeutic reversal of these effects with EVs would be beneficial and could be achieved, for example, by modulating the macrophage phenotype or regulating antigen presentation by dendritic cells. Additionally, intended targeting of EVs to MPS macrophages for replication and repackaging of their molecules into new vesicle subtype can allow for their specific targeting to appropriate populations of acceptor cells. Herein, we briefly discuss the under-explored aspects of the MPS-EV interactions that undoubtedly require further research in order to accelerate the therapeutic use of EVs.

Sevoflurane Improves Ventricular Conduction by Exosomes Derived from Rat Cardiac Fibroblasts After Hypothermic Global Ischemia-Reperfusion Injury

Purpose

This study investigated the effect of exosomes derived from sevoflurane-treated cardiac fibroblasts (Sev-CFs-Exo) on reperfusion arrhythmias (RA), ventricular conduction, and myocardial ischemia-reperfusion injury (MIRI).

Methods

Primary cardiac fibroblasts (CFs) were isolated from the hearts of neonatal rats and identified by morphology and immunofluorescence. Exosomes were isolated from CFs at passages 2-3 after they had been treated with 2.5% sevoflurane for an hour and cultivated for 24-48 hours. The control group was CFs that did not receive any treatment. The hypothermic global ischemia-reperfusion injury model was established using the Langendorff perfusion technique following injection with exosomes through the caudal vein. Multi-electrode array (MEA) mapping was used to investigate the changes in RA and ventricular conduction in isolated hearts. Western blots and immunofluorescence were used to examine the relative expression and location of connexin 43 (Cx43). In addition, the MIRI was evaluated with triphenyl tetrazolium chloride and Hematoxylin-Eosin staining.

Results

The primary CFs had a variety of morphologies, no spontaneous pulsation, and were vimentin-positive, which confirmed their successful isolation. Sev-CFs-Exo increased the heart rate (HR) at reperfusion for 15 minutes (T₂) and 30 minutes (T₃) and lowered the score and duration of RA and the time for restoration of heartbeat in reperfusion. Meanwhile, Sev-CFs-Exo increased conduction velocity (CV), decreased absolute inhomogeneity (P_5-95) and inhomogeneity index (P_5-95/P₅₀) at T₂ and T₃, as well as promoted the recovery of HR, CV, P_5-95 and P_5-95/P₅₀ after hypothermic global ischemia-reperfusion injury. Furthermore, Sev-CFs-Exo raised expression and reduced lateralization of Cx43, and improved myocardial infarct sizes and cellular necrosis. However, while cardiac fibroblast-derived exosomes (CFs-Exo) showed similar cardioprotective effects, the outcomes were not as significant.

Conclusion

Sevoflurane reduces the risk of RA and improves ventricular conduction and MIRI by CFs-Exo, and this may be driven by the expression and location of Cx43.

Engineered Extracellular Vesicles as a Targeted Delivery Platform for Precision Therapy

Extracellular vesicles (EVs)-based cell-free strategy has shown therapeutic potential in tissue regeneration. Due to their important roles in intercellular communications and their natural ability to shield cargos from degradation, EVs are also emerged as novel delivery vehicles for various bioactive molecules and drugs. Accumulating studies have revealed that EVs can be modified to enhance their efficacy and specificity for the treatment of many diseases. Engineered EVs are poised as the next generation of targeted delivery platform in the field of precision therapy. In this review, the unique properties of EVs are overviewed in terms of their biogenesis, contents, surface features and biological functions, and the recent advances in the strategies of engineered EVs construction are summarized. Additionally, we also discuss the potential applications of engineered EVs in targeted therapy of cancer and damaged tissues, and evaluate the opportunities and challenges for translating them into clinical practice.

Visualization of cardiac uptake of bone marrow mesenchymal stem cell-derived extracellular vesicles after intramyocardial or intravenous injection in murine myocardial infarction

In animal models, human bone marrow mesenchymal stem cell-derived extracellular vesicles (MSC-EV) have been found to have beneficial effects in cardiovascular disease, but only when administered via intramyocardial injection. The biodistribution of either intravenous or intramyocardial injection of MSC-EV in the presence of myocardial injury is uncharacterized at this time. We hypothesized that intramyocardial injection will ensure delivery of MSC-EV to the ischemic myocardium, while intravenous injection will not. Human bone marrow mesenchymal stem cells were cultured and the MSC-EV were isolated and characterized. The MSC-EVs were then labeled with DiD lipid dye. FVB mice with normal cardiac function underwent left coronary artery ligation followed by either peri-infarct intramyocardial or tail vein injection of 3*106 or 2*109 particles of DiD-labeled MSC-EV or a DiD-saline control. The heart, lungs, liver, spleen and kidneys were harvested 2 h post-injection and were submitted for fluorescent molecular tomography imaging. Myocardial uptake of MSC-EV was only visualized after intramyocardial injection of 2*109 MSC-EV particles (p = 0.01) compared to control, and there were no differences in cardiac fluorescence after tail vein injection of MSC-EV (p = 0.5). There was no significantly detectable MSC-EV uptake in other organs after intramyocardial injection. After tail vein injection of 2*109 particles of MSC-EV, the liver (p = 0.02) and spleen (p = 0.04) appeared to have diffuse MSC-EV uptake compared to controls. Even in the presence of myocardial injury, only intramyocardial but not intravenous administration resulted in detectable levels of MSC-EV in the ischemic myocardium. This study confirms the role for intramyocardial injection in maximal and effective delivery of MSC-EV. Our ongoing studies aimed at developing bioengineered MSC-EV for targeted delivery to the heart may render MSC-EV clinically applicable for cardiovascular disease.

An injectable hydrogel scaffold with IL-1β-activated MSC-derived exosomes for the treatment of endometritis

Chronic endometritis is a common gynecological disease resulting from various long-term recurrent infections, and is closely related to myositis, miscarriage, and even infertility. There is still no satisfactory treatment method currently in clinical therapy. Mesenchymal stem cell (MSC)-derived exosomes, an important kind of paracrine product, have been used to treat inflammatory diseases due to their promising immunomodulatory function and tissue repair ability similar to MSCs. Considering that the exosome contents and functions are regulated by the MSC status and the MSC status is significantly influenced by its surrounding microenvironment, we propose a hypothesis that exosomes derived from inflammation-simulated MSCs will possess stronger inhibition ability for inflammation. Herein, we used IL-1β to activate rat bone MSCs for obtaining β-exo and constructed an injectable polypeptide hydrogel scaffold by loading β-exo (β-exo@pep) for an in situ slow release of β-exo. The results showed that the polypeptide hydrogel can provide a sustained release of exosomes in 14 days. The β-exo@pep composite hydrogel can more effectively inhibit the production of inflammatory factors such as TNF-α, IL-1β, and IFN-γ, while it can promote the production of anti-inflammatory factors such as Arg-1, IL-6, and IL-10. The β-exo@pep composite hydrogel significantly promoted cell migration, invasion, and vessel tube formation in vitro. The experiments in a rat model of endometritis proved that the β-exo@pep composite scaffold possessed excellent ability towards anti-inflammation and endometrial regeneration. The research studies on the molecular mechanism revealed that the protein expressions of HMGB1 and phosphorylated IKB-α and p65 are down-regulated in the cells treated with β-exo@pep, indicating the involvement of the NF-κB signaling pathway. This study provides an effective method for the treatment of chronic endometritis, which is promising for clinical use.

Extracellular Vesicles and Ischemic Cardiovascular Diseases

Characterized by coronary artery obstruction or stenosis, ischemic cardiovascular diseases as advanced stages of coronary heart diseases commonly lead to left ventricular aneurysm, ventricular septal defect, and mitral insufficiency. Extracellular vesicles (EVs) secreted by diverse cells in the body exert roles in cell-cell interactions and intrinsic cellular regulations. With a lipid double-layer membrane and biological components such as DNA, protein, mRNA, microRNAs (miRNA), and siRNA inside, the EVs function as paracrine signaling for the pathophysiology of ischemic cardiovascular diseases and maintenance of the cardiac homeostasis. Unlike stem cell transplantation with the potential tumorigenicity and immunogenicity, the EV-based therapeutic strategy is proposed to satisfy the demand for cardiac repair and regeneration while the circulating EVs detected by a noninvasive approach can act as precious biomarkers. In this chapter, we extensively summarize the cardioprotective functions of native EVs and bioengineered EVs released from stem cells, cardiomyocytes, cardiac progenitor cells (CPCs), endothelial cells, fibroblast, smooth muscle cells, and immune cells. In addition, the potential of EVs as robust molecule biomarkers is discussed for clinical diagnosis of ischemic cardiovascular disease, attributed to the same pathology of EVs as that of their origin. Finally, we highlight EV-based therapy as a biocompatible alternative to direct cell-based therapy for ischemic cardiovascular diseases.

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.

Functions and therapeutic potentials of exosomes in osteosarcoma

Osteosarcoma is a primary malignant tumor of the skeleton with the morbidity of 2.5 in 1 million. The regularly on-set is in the epiphysis of the extremities with a high possibility of early metastasis, rapid progression, and poor prognosis. The survival rate of patients with metastatic or recurrent osteosarcoma remains low, and novel diagnostic and therapeutic methods are urgently needed. Exosomes are extracellular vesicles 30-150 nm in diameter secreted by various cells that are widely present in various body fluids. Exosomes are abundant in biologically active components such as proteins, nucleic acids, and lipids. Exosomes participate in numerous physiological and pathological processes via intercellular substance exchange and signaling. This review presents the novel findings of exosomes in osteosarcoma in diagnosis, prognosis, and therapeutic aspects.

Radiovesicolomics-new approach in medical imaging

This review introduce extracellular vesicles (EVs) to a molecular imaging field. The idea of modern analyses based on the use of omics studies, using high-throughput methods to characterize the molecular content of a single biological system, vesicolomics seems to be the new approach to collect molecular data about EV content, to find novel biomarkers or therapeutic targets. The use of various imaging techniques, including those based on radionuclides as positron emission tomography (PET) or single photon emission computed tomography (SPECT), combining molecular data on EVs, opens up the new space for radiovesicolomics—a new approach to be used in theranostics.

Heart-targeting exosomes from human cardiosphere-derived cells improve the therapeutic effect on cardiac hypertrophy

Exosomes of human cardiosphere-derived cells (CDCs) are very promising for treating cardiovascular disorders. However, the current challenge is inconvenient delivery methods of exosomes for clinical application. The present study aims to explore the potential to enhance the therapeutic effect of exosome (EXO) from human CDCs to myocardial hypertrophy. A heart homing peptide (HHP) was displayed on the surface of exosomes derived from CDCs that were forced to express the HHP fused on the N-terminus of the lysosomal-associated membrane protein 2b (LAMP2b). The cardiomyocyte-targeting capability of exosomes were analyzed and their therapeutic effects were evaluated in a mouse model of myocardial hypertrophy induced by transverse aorta constriction (TAC). The molecular mechanisms of the therapeutic effects were dissected in angiotensin II-induced neonatal rat cardiomyocyte (NRCMs) hypertrophy model using a combination of biochemistry, immunohistochemistry and molecular biology techniques. We found that HHP-exosomes (HHP-EXO) accumulated more in mouse hearts after intravenous delivery and in cultured NRCMs than control exosomes (CON-EXO). Cardiac function of TAC mice was significantly improved with intravenous HHP-EXO administration. Left ventricular hypertrophy was reduced more by HHP-EXO than CON-EXO via inhibition of β-MHC, BNP, GP130, p-STAT3, p-ERK1/2, and p-AKT. Similar results were obtained in angiotensin II-induced hypertrophy of NRCMs, in which the beneficial effects of HHP-EXO were abolished by miRNA-148a inhibition. Our results indicate that HHP-EXO preferentially target the heart and improve the therapeutic effect of CDCs-exosomes on cardiac hypertrophy. The beneficial therapeutic effect is most likely attributed to miRNA-148a-mediated suppression of GP130, which in turn inhibits STAT3/ERK1/2/AKT signaling pathway, leading to improved cardiac function and remodeling.

Bioengineering Extracellular Vesicles for the Treatment of Cardiovascular Diseases

Cardiovascular diseases (CVD) remain one of the leading causes of mortality worldwide. Despite recent advances in diagnosis and interventions, there is still a crucial need for new multifaceted therapeutics that can address the complicated pathophysiological mechanisms driving CVD. Extracellular vesicles (EVs) are nanovesicles that are secreted by all types of cells to transport molecular cargo and regulate intracellular communication. EVs represent a growing field of nanotheranostics that can be leveraged as diagnostic biomarkers for the early detection of CVD and as targeted drug delivery vesicles to promote cardiovascular repair and recovery. Though a promising tool for CVD therapy, the clinical application of EVs is limited by the inherent challenges in EV isolation, standardization, and delivery. Hence, this review will present the therapeutic potential of EVs and introduce bioengineering strategies that augment their natural functions in CVD.

Extracellular vesicles: A new diagnostic biomarker and targeted drug in osteosarcoma

Osteosarcoma (OS) is a primary bone cancer that is highly prevalent among adolescents and adults below the age of 20 years. The prognostic outcome of metastatic OS or relapse is extremely poor; thus, developing new diagnostic and therapeutic strategies for treating OS is necessary. Extracellular vesicles (EVs) ranging from 30–150 nm in diameter are commonly produced in different cells and are found in various types of body fluids. EVs are rich in biologically active components like proteins, lipids, and nucleic acids. They also strongly affect pathophysiological processes by modulating the intercellular signaling pathways and the exchange of biomolecules. Many studies have found that EVs influence the occurrence, development, and metastasis of osteosarcoma. The regulation of inflammatory communication pathways by EVs affects OS and other bone-related pathological conditions, such as osteoarthritis and rheumatoid arthritis. In this study, we reviewed the latest findings related to diagnosis, prognosis prediction, and the development of treatment strategies for OS from the perspective of EVs.

High-efficiency brain-targeted intranasal delivery of BDNF mediated by engineered exosomes to promote remyelination

The regeneration of myelin sheaths is the ultimate goal of the treatment of demyelination disease, including multiple sclerosis (MS). However, current drugs for MS mainly target the immune system and can only slow down the disease development and do not promote the differentiation of oligodendrocyte precursor cells (OPCs) abundant in the myelin injury region into mature oligodendrocytes to form a new myelin sheath. Brain-derived neurotrophic factor (BDNF) plays an important role in the regulation of OPC proliferation and differentiation into mature oligodendrocytes. Exosomes, a kind of nanoscale membrane vesicle secreted by cells, can be used as potential therapeutic drug delivery vectors for central nervous system diseases. Here, brain-targeted modification and BDNF intracellular-loaded exosomes were produced through engineering HEK293T cells, which can promote the differentiation of OPCs into mature oligodendrocytes in vitro. The intranasal administration of the brain-targeted engineered exosome-mediated BDNF was a highly effective delivery route to the brain and had a significant therapeutic effect on remyelination and motor coordination ability improvement in demyelination model mice. The combination of intranasal administration with brain-targeted and BDNF-loaded designed exosomes provides a strategy for efficient drug delivery and treatment of central nervous system diseases.

Fabrication of Tβ4-Exosome-releasing artificial stem cells for myocardial infarction therapy by improving coronary collateralization

Currently, stem cell transplantations in cardiac repair are limited owing to disadvantages, such as immunological rejection and poor cell viability. Although direct injection of exosomes can have a curative effect similar to that of stem cell transplantation, high clearance hinders its application in clinical practice. Previous reports suggested that induction of coronary collateralization can be a desired method of adjunctive therapy for someone who had missed the optimal operation time to attenuate myocardial ischemia. In this study, to mimic the paracrine and biological activity of stem cells, we developed artificial stem cells that can continuously release Tβ4-exosomes (Tβ4-ASCs) by encapsulating specific exosomes within microspheres using microfluidics technology. The results show that Tβ4-ASCs can greatly promote coronary collateralization in the periphery of the myocardial infarcted area, and its therapeutic effect is superior to that of directly injecting the exosomes. In addition, to better understand how it works, we demonstrated that the Tβ4-ASC-derived exosomes can enhance the angiogenic capacity of coronary endothelial cells (CAECs) via the miR-17-5p/PHD3/Hif-1α pathway. In brief, as artificial stem cells, Tβ4-ASCs can constantly release functional exosomes and stimulate the formation of collateral circulation after myocardial infarction, providing a feasible and alternative method for clinical revascularization.

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Inspired by the paracrine of stem cells, we fabricated artificial stem cells (Tβ4-ASCs) by loading engineered Tβ4-exosomes with microspheres using microfluidics technology.

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Tβ4-ASCs stimulate the formation of coronary collateralization in myocardial infarcted area through a slowly sustained release of engineered Tβ4-exosomes.

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Tβ4-ASCs improve coronary collateralization via the miR-17-5p/PHD3/Hif-1α signaling pathway.

Mesenchymal Stem Cell-Derived Extracellular Vesicles as Idiopathic Pulmonary Fibrosis Microenvironment Targeted Delivery

Idiopathic pulmonary fibrosis (IPF) affects an increasing number of people globally, yet treatment options remain limited. At present, conventional treatments depending on drug therapy do not show an ideal effect in reversing the lung damage or extending the lives of IPF patients. In recent years, more and more attention has focused on extracellular vesicles (EVs) which show extraordinary therapeutic effects in inflammation, fibrosis disease, and tissue damage repair in many kinds of disease therapy. More importantly, EVs can be modified or used as a drug or cytokine delivery tool, targeting injury sites to enhance treatment efficiency. In light of this, the treatment strategy of mesenchymal stem cell-extracellular vesicles (MSC-EVs) targeting the pulmonary microenvironment for IPF provides a new idea for the treatment of IPF. In this review, we summarized the inflammation, immune dysregulation, and extracellular matrix microenvironment (ECM) disorders in the IPF microenvironment in order to reveal the treatment strategy of MSC-EVs targeting the pulmonary microenvironment for IPF.

Extracellular vesicles as bioactive nanotherapeutics: An emerging paradigm for regenerative medicine

In recent decades, extracellular vesicles (EVs), as bioactive cell-secreted nanoparticles which are involved in various physiological and pathological processes including cell proliferation, immune regulation, angiogenesis and tissue repair, have emerged as one of the most attractive nanotherapeutics for regenerative medicine. Herein we provide a systematic review of the latest progress of EVs for regenerative applications. Firstly, we will briefly introduce the biogenesis, function and isolation technology of EVs. Then, the underlying therapeutic mechanisms of the native unmodified EVs and engineering strategies of the modified EVs as regenerative entities will be discussed. Subsequently, the main focus will be placed on the tissue repair and regeneration applications of EVs on various organs including brain, heart, bone and cartilage, liver and kidney, as well as skin. More importantly, current clinical trials of EVs for regenerative medicine will also be briefly highlighted. Finally, the future challenges and insightful perspectives of the currently developed EV-based nanotherapeutics in biomedicine will be discussed. In short, the bioactive EV-based nanotherapeutics have opened new horizons for biologists, chemists, nanoscientists, pharmacists, as well as clinicians, making possible powerful tools and therapies for regenerative medicine.

Extracellular Vesicles in Cardiovascular Diseases: Diagnosis and Therapy

Cardiovascular diseases (CVDs) are the leading cause of global mortality. Therapy of CVDs is still a great challenge since many advanced therapies have been developed. Multiple cell types produce nano-sized extracellular vesicles (EVs), including cardiovascular system-related cells and stem cells. Compelling evidence reveals that EVs are associated with the pathophysiological processes of CVDs. Recently researches focus on the clinical transformation in EVs-based diagnosis, prognosis, therapies, and drug delivery systems. In this review, we firstly discuss the current knowledge about the biophysical properties and biological components of EVs. Secondly, we will focus on the functions of EVs on CVDs, and outline the latest advances of EVs as prognostic and diagnostic biomarkers, and therapeutic agents. Finally, we will introduce the specific application of EVs as a novel drug delivery system and its application in CVDs therapy. Specific attention will be paid to summarize the perspectives, challenges, and applications on EVs’ clinical and industrial transformation.

A Novel, Cell-Free Therapy to Enter Our Hearts: The Potential Role of Small EVs in Prevention and Treatment of CVD

Heart disease constitutes one of the leading causes of morbidity and mortality worldwide. Current therapeutic techniques, such as interventional revascularization, although lifesaving, come along with myocardial injury related to the reperfusion itself, called ischemia-reperfusion injury, which is an added factor for increased morbidity. For that reason, there is an imperative need for novel therapies to be developed that would either prevent or treat myocardial injury. Extracellular vesicles (EVs), specifically small EVs (sEVs), have proven to be important mediators of intercellular communication. The fact that they carry information reflecting that of the parental cell makes them an ideal candidate for diagnostic purposes. sEVs derived from immunoregulatory cells, such as mesenchymal stem cells or cardiac progenitor cells, could also be used therapeutically to exert the primary immunomodulatory function but without carrying the side effects related to cell therapy. Furthermore, as a natural product, they have the added advantage of low immunogenicity, offering the potential for safe drug delivery. In the field of cardiology, there has been great interest in the therapeutic and diagnostic potential of sEVs with significant translational potential. Here, we review the potential use of sEVs in the context of myocardial ischemia and ischemia-reperfusion injury.

Human Amniotic Epithelial Cells Secretome: Components, Bioactivity, and Challenges

Human amniotic epithelial cells (hAECs) derived from placental tissue have received significant attention as a promising tool in regenerative medicine. Several studies demonstrated their anti-inflammatory, anti-fibrotic, and tissue repair potentials. These effects were further shown to be retained in the conditioned medium of hAECs, suggesting their paracrine nature. The concept of utilizing the hAEC-secretome has thus evolved as a therapeutic cell-free option. In this article, we review the different components and constituents of hAEC-secretome and their influence as demonstrated through experimental studies in the current literature. Studies examining the effects of conditioned medium, exosomes, and micro-RNA (miRNA) derived from hAECs are included in this review. The challenges facing the application of this cell-free approach will also be discussed based on the current evidence.

Increasing the Therapeutic Efficacy of Extracellular Vesicles From the Antigen-Specific Antibody and Light Chain Perspective

Due to their exceptional properties, extracellular vesicles (EVs) receive special attention as next generation biotherapeutics and vehicles for drug delivery. However, despite having many advantages over cell-based therapies, EVs usually exert lower therapeutic efficacy. This results from a number of hurdles that are faced by the EV-based approaches. Administered EVs could be rapidly cleared by the mononuclear phagocytes as well as can randomly distribute within various tissues, making tissue penetration and cell targeting insufficient. However, recent research findings imply that these limitations could be overcome with the use of antigen-specific antibodies and light chains. Major histocompatibility complex (MHC) class II-expressing EVs have been shown to form aggregates after co-incubation with antigen-specific antibodies, which greatly enhanced their biological efficacy. On the other hand, EVs could be coated with antibody light chains of chosen specificity to direct them towards desired target cell population. Both findings open up a promising perspective to achieve the highest efficacy of the EV-based approaches. Herein we discuss the opportunities for enhancing extracellular vesicle’s biological activity by using specific antibodies and light chains in the context of the challenges faced by such therapeutic approach.

Restoring Cardiac Functions after Myocardial Infarction-Ischemia/Reperfusion via an Exosome Anchoring Conductive Hydrogel

Both myocardial infarction (MI) and the follow-up reperfusion will lead to an inevitable injury to myocardial tissues, such as cardiac dysfunctions, fibrosis, and reduction of intercellular cell-to-cell interactions. Recently, exosomes (Exo) derived from stem cells have demonstrated a robust capability to promote angiogenesis and tissue repair. However, the short half-life of Exo and rapid clearance lead to insufficient therapeutic doses in the lesion area. Herein, an injectable conductive hydrogel is constructed to bind Exo derived from human umbilical cord mesenchymal stem cells to treat myocardial injuries after myocardial infarction-ischemia/reperfusion (MI-I/R). To this end, a hyperbranched epoxy macromer (EHBPE) grafted by an aniline tetramer (AT) was synthesized to cross-link thiolated hyaluronic acid (HA-SH) and thiolated Exo anchoring a CP05 peptide via an epoxy/thiol "click" reaction. The resulting Gel@Exo composite system possesses multiple features, such as controllable gelation kinetics, shear-thinning injectability, conductivity matching the native myocardium, soft and dynamic stability adapting to heartbeats, and excellent cytocompatibility. After being injected into injured hearts of rats, the hydrogel effectively prolongs the retention of Exo in the ischemic myocardium. The cardiac functions have been considerably improved by Gel@Exo administration, as indicated by the enhancing ejection fraction and fractional shortening, and reducing fibrosis area. Immunofluorescence staining and reverse transcription-polymerase chain reaction (RT-PCR) results demonstrate that the expression of cardiac-related proteins (Cx43, Ki67, CD31, and α-SMA) and genes (VEGF-A, VEGF-B, vWF, TGF-β1, MMP-9, and Serca2a) are remarkably upregulated. The conductive Gel@Exo system can significantly improve cell-to-cell interactions, promote cell proliferation and angiogenesis, and result in a prominent therapeutic effect on MI-I/R, providing a promising therapeutic method for injured myocardial tissues.

A New Role for Extracellular Vesicles in Cardiac Tissue Engineering and Regenerative Medicine

Cardiovascular diseases are the leading cause of death worldwide. Discovering new therapies to treat heart disease requires improved understanding of cardiac physiology at a cellular level. Extracellular vesicles (EVs) are plasma membrane-bound nano- and microparticles secreted by cells and known to play key roles in intercellular communication, often through transfer of biomolecular cargo. Advances in EV research have established techniques for EV isolation from tissue culture media or biofluids, as well as standards for quantitation and biomolecular characterization. EVs released by cardiac cells are known to be involved in regulating cardiac physiology as well as in the progression of myocardial diseases. Due to difficulty accessing the heart in vivo, advanced in vitro cardiac 'tissues-on-a-chip' have become a recent focus for studying EVs in the heart. These physiologically relevant models are producing new insight into the role of EVs in cardiac physiology and disease while providing a useful platform for screening novel EV-based therapeutics for cardiac tissue regeneration post-injury. Numerous hurdles have stalled the clinical translation of EV therapeutics for heart patients, but tissue-on-a-chip models are playing an important role in bridging the translational gap, improving mechanistic understanding of EV signalling in cardiac physiology, disease, and repair.

Cardiac Extracellular Matrix Hydrogel Enriched with Polyethylene Glycol Presents Improved Gelation Time and Increased On-Target Site Retention of Extracellular Vesicles

Stem-cell-derived extracellular vesicles (EVs) have demonstrated multiple beneficial effects in preclinical models of cardiac diseases. However, poor retention at the target site may limit their therapeutic efficacy. Cardiac extracellular matrix hydrogels (cECMH) seem promising as drug-delivery materials and could improve the retention of EVs, but may be limited by their long gelation time and soft mechanical properties. Our objective was to develop and characterize an optimized product combining cECMH, polyethylene glycol (PEG), and EVs (EVs–PEG–cECMH) in an attempt to overcome their individual limitations: long gelation time of the cECMH and poor retention of the EVs. The new combined product presented improved physicochemical properties (60% reduction in half gelation time, p < 0.001, and threefold increase in storage modulus, p < 0.01, vs. cECMH alone), while preserving injectability and biodegradability. It also maintained in vitro bioactivity of its individual components (55% reduction in cellular senescence vs. serum-free medium, p < 0.001, similar to EVs and cECMH alone) and increased on-site retention in vivo (fourfold increase vs. EVs alone, p < 0.05). In conclusion, the combination of EVs–PEG–cECMH is a potential multipronged product with improved gelation time and mechanical properties, increased on-site retention, and maintained bioactivity that, all together, may translate into boosted therapeutic efficacy.

High Therapeutic and Esthetic Properties of Extracellular Vesicles Produced from the Stem Cells and Their Spheroids Cultured from Ocular Surgery-Derived Waste Orbicularis Oculi Muscle Tissues

Extracellular vesicles (EVs) are paracrine factors that mediate stem cell therapeutics. We aimed at evaluating the possible therapeutic and esthetic applications of EVs prepared from the waste human facial tissue-derived orbicularis oculi muscle stem cells (OOM-SCs). OOM-SCs were isolated from the ocular tissues (from elders and youngsters) after upper eyelid blepharoplasty or epiblepharon surgeries. EVs were prepared from the OOM-SCs (OOM-SC-EVs) and their three-dimensional spheroids. OOM-SCs showed a spindle-like morphology with trilineage differentiation capacity, positive expression of CD105, CD 90, and CD73, and negative expression of CD45 and CD34, and their stem cell properties were compared with other adult mesenchymal stem cells. OOM-SC-EVs showed a high inhibitory effect on melanin synthesis in B16F10 cells by blocking tyrosinase activity. OOM-SC-EVs treatment led to a significant attenuation of senescence-associated changes, a decrease in reactive oxygen species generation, and an upregulation of antioxidant genes. We demonstrated the regeneration activity of OOM-SC-EVs in in vitro wound healing of normal human dermal fibroblasts and upregulation of anti-wrinkle-related genes and confirmed the therapeutic potential of OOM-SC-EVs in the healing of the in vivo wound model. Our study provides promising therapeutic and esthetic applications of OOM-SC-EVs, which can be obtained from the ocular surgery-derived waste human facial tissues.

Elastomeric Cardiowrap Scaffolds Functionalized with Mesenchymal Stem Cells-Derived Exosomes Induce a Positive Modulation in the Inflammatory and Wound Healing Response of Mesenchymal Stem Cell and Macrophage

A challenge in contractile restoration of myocardial scars is one of the principal aims in cardiovascular surgery. Recently, a new potent biological tool used within healing processes is represented by exosomes derived from mesenchymal stem cells (MSCs). These cells are the well-known extracellular nanovesicles released from cells to facilitate cell function and communication. In this work, a combination of elastomeric membranes and exosomes was obtained and tested as a bioimplant. Mesenchymal stem cells (MSCs) and macrophages were seeded into the scaffold (polycaprolactone) and filled with exosomes derived from MSCs. Cells were tested for proliferation with an MTT test, and for wound healing properties and macrophage polarization by gene expression. Moreover, morphological analyses of their ability to colonize the scaffolds surfaces have been further evaluated. Results confirm that exosomes were easily entrapped onto the surface of the elastomeric scaffolds, increasing the wound healing properties and collagen type I and vitronectin of the MSC, and improving the M2 phenotype of the macrophages, mainly thanks to the increase in miRNA124 and decrease in miRNA 125. We can conclude that the enrichment of elastomeric scaffolds functionalized with exosomes is as an effective strategy to improve myocardial regeneration.

Regulation of Nrf2 signaling pathway in heart failure: Role of extracellular vesicles and non-coding RNAs

The balance between pro- and antioxidant molecules has been established as an important driving force in the pathogenesis of cardiovascular disease. Chronic heart failure is associated with oxidative stress in the myocardium and globally. Redox balance in the heart and brain is controlled, in part, by antioxidant proteins regulated by the transcription factor Nuclear factor erythroid 2-related factor 2 (Nrf2), which is reduced in the heart failure state. Nrf2 can, in turn, be regulated by a variety of mechanisms including circulating microRNAs (miRNAs) encapsulated in extracellular vesicles (EVs) derived from multiple cell types in the heart. Here, we review the role of the Nrf2 and antioxidant enzyme signaling pathway in mediating redox balance in the myocardium and the brain in the heart failure state. This review focuses on Nrf2 and antioxidant protein regulation in the heart and brain by miRNA-enriched EVs in the setting of heart failure. We discuss EV-mediated intra- and inter-organ communications especially, communication between the heart and brain via an EV pathway that mediates cardiac function and sympatho-excitation in heart failure. Importantly, we speculate how engineered EVs with specific miRNAs or antagomirs may be used in a therapeutic manner in heart failure.