Extracellular Vesicles: How Drug and Pathology Interfere With Their Biogenesis and Function

Profiling of circulating extracellular vesicle microRNAs reveals diagnostic potential and pathways in non-obstructive and obstructive azoospermia†

The accurate diagnosis of non-obstructive azoospermia and obstructive azoospermia is crucial for selecting appropriate clinical treatments. This study aimed to investigate the pivotal role of microRNAs in circulating plasma extracellular vesicles in distinguishing between non-obstructive azoospermia and obstructive azoospermia, as well as uncovering the signaling pathways involved in azoospermia pathogenesis. In this study, differential expression of extracellular vesicle miR-513c-5p and miR-202-5p was observed between non-obstructive azoospermia and obstructive azoospermia patients, while the selenocompound metabolism pathway could be affected in azoospermia through Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis. The predictive power of these microRNAs was evaluated using receiver characteristic operator-area under the curve analysis, demonstrating promising sensitivity, specificity, and area under the curve values. A binomial regression equation incorporating circulating plasma levels of extracellular vesicles miR-202-5p and miR-513c-5p along with follicle-stimulating hormone was calculated to provide a clinically applicable method for diagnosing non-obstructive azoospermia and obstructive azoospermia. This study presents a potentially non-invasive testing approach for distinguishing between non-obstructive azoospermia and obstructive azoospermia, offering a possibly valuable tool for clinical practice.

Extracellular vesicles as the next-generation modulators of pharmacokinetics and pharmacodynamics of medications and their potential as adjuvant therapeutics

BACKGROUND AND MAIN BODY

Pharmacokinetics (PK) and pharmacodynamics (PD) are central concepts to guide the dosage and administration of drug therapies and are essential to consider for both healthcare professionals and researchers in therapeutic planning and drug discovery. PK/PD properties of a drug significantly influence variability in response to treatment, including therapeutic failure or excessive medication-related harm. Furthermore, suboptimal PK properties constitute a significant barrier to further development for some candidate treatments in drug discovery. This article describes how extracellular vesicles (EVs) affect different aspects of PK and PD of medications and their potential to modulate PK and PD properties to address problematic PK/PD profiles of drugs. We reviewed EVs' intrinsic effects on cell behaviours and medication responses. We also described how surface and cargo modifications can enhance EV functionalities and enable them as adjuvants to optimise the PK/PD profile of conventional medications. Furthermore, we demonstrated that various bioengineering strategies can be used to modify the properties of EVs, hence enhancing their potential to modulate PK and PD profile of medications.

CONCLUSION

This review uncovers the critical role of EVs in PK and PD modulation and motivates further research and the development of assays to unfold EVs' full potential in solving PK and PD-related problems. However, while we have shown that EVs play a vital role in modulating PK and PD properties of medications, we postulated that it is essential to define the context of use when designing and utilising EVs in pharmaceutical and medical applications.

HIGHLIGHTS

Existing solutions for pharmacokinetics and pharmacodynamics modulation are limited. Extracellular vesicles can optimise pharmacokinetics as a drug delivery vehicle. Biogenesis and administration of extracellular vesicles can signal cell response. The pharmaceutical potential of extracellular vesicles can be enhanced by surface and cargo bioengineering. When using extracellular vesicles as modulators of pharmacokinetics and pharmacodynamics, the 'context of use' must be considered.

Cargo exchange between human and bacterial extracellular vesicles in gestational tissues: a new paradigm in communication and immune development

Host-bacteria and bacteria-bacteria interactions can be facilitated by extracellular vesicles (EVs) secreted by both human and bacterial cells. Human and bacterial EVs (BEVs) propagate and transfer immunogenic cargos that may elicit immune responses in nearby or distant recipient cells/tissues. Hence, direct colonization of tissues by bacterial cells is not required for immunogenic stimulation. This phenomenon is important in the feto-maternal interface, where optimum tolerance between the mother and fetus is required for a successful pregnancy. Though the intrauterine cavity is widely considered sterile, BEVs from diverse sources have been identified in the placenta and amniotic cavity. These BEVs can be internalized by human cells, which may help them evade host immune surveillance. Though it appears logical, whether bacterial cells internalize human EVs or human EV cargo is yet to be determined. However, the presence of BEVs in placental tissues or amniotic cavity is believed to trigger a low-grade immune response that primes the fetal immune system for ex-utero survival, but is insufficient to disrupt the progression of pregnancy or cause immune intolerance required for adverse pregnancy events. Nevertheless, the exchange of bioactive cargos between human and BEVs, and the mechanical underpinnings and health implications of such interactions, especially during pregnancy, are still understudied. Therefore, while focusing on the feto-maternal interface, we discussed how human cells take up BEVs and whether bacterial cells take up human EVs or their cargo, the exchange of cargos between human and BEVs, host cell (feto-maternal) inflammatory responses to BEV immunogenic stimulation, and associations of these interactions with fetal immune priming and adverse reproductive outcomes such as preeclampsia and preterm birth.

Extracellular Vesicle- and Mitochondria-Based Targeting of Non-Small Cell Lung Cancer Response to Radiation: Challenges and Perspectives

During the cell life cycle, extracellular vesicles (EVs) transport different cargos, including organelles, proteins, RNAs, DNAs, metabolites, etc., that influence cell proliferation and apoptosis in recipient cells. EVs from metastatic cancer cells remodel the extracellular matrix and cells of the tumor microenvironment (TME), promoting tumor invasion and metastatic niche preparation. Although the process is not fully understood, evidence suggests that EVs facilitate genetic material transfer between cells. In the context of NSCLC, EVs can mediate intercellular mitochondrial (Mt) transfer, delivering mitochondria organelle (MtO), mitochondrial DNA (mtDNA), and/or mtRNA/proteinaceous cargo signatures (MtS) through different mechanisms. On the other hand, certain populations of cancer cells can hijack the MtO from TME cells mainly by using tunneling nanotubes (TNTs). This transfer aids in restoring mitochondrial function, benefiting benign cells with impaired metabolism and enabling restoration of their metabolic activity. However, the impact of transferring mitochondria versus transplanting intact mitochondrial organelles in cancer remains uncertain and the subject of debate. Some studies suggest that EV-mediated mitochondria delivery to cancer cells can impact how cancer responds to radiation. It might make the cancer more resistant or more sensitive to radiation. In our review, we aimed to point out the current controversy surrounding experimental data and to highlight new paradigm-shifting modalities in radiation therapy that could potentially overcome cancer resistance mechanisms in NSCLC.

Extracellular vesicle features are associated with COVID-19 severity

COVID-19 is heterogeneous; therefore, it is crucial to identify early biomarkers for adverse outcomes. Extracellular vesicles (EV) are involved in the pathophysiology of COVID-19 and have both negative and positive effects. The objective of this study was to identify the potential role of EV in the prognostic stratification of COVID-19 patients. A total of 146 patients with severe or critical COVID-19 were enrolled. Demographic and comorbidity characteristics were collected, together with routine haematology, blood chemistry and lymphocyte subpopulation data. Flow cytometric characterization of the dimensional and antigenic properties of COVID-19 patients' plasma EVs was conducted. Elastic net logistic regression with cross-validation was employed to identify the best model for classifying critically ill patients. Features of smaller EVs (i.e. the fraction of EVs smaller than 200 nm expressing either cluster of differentiation [CD] 31, CD 140b or CD 42b), albuminemia and the percentage of monocytes expressing human leukocyte antigen DR (HLA-DR) were associated with a better outcome. Conversely, the proportion of larger EVs expressing N-cadherin, CD 34, CD 56, CD31 or CD 45, interleukin 6, red cell width distribution (RDW), N-terminal pro-brain natriuretic peptide (NT-proBNP), age, procalcitonin, Charlson Comorbidity Index and pro-adrenomedullin were associated with disease severity. Therefore, the simultaneous assessment of EV dimensions and their antigenic properties complements laboratory workup and helps in patient stratification.

Enhancing the Cellular Production of Extracellular Vesicles for Developing Therapeutic Applications

Extracellular vesicles (EVs) have various advantageous properties, including a small size, high biocompatibility, efficient cargo loading, and precise cell targeting ability, making them promising tools for therapeutic development. EVs have been increasingly explored for applications like drug delivery. However, due to limited cellular secretion rates of EVs, wide-scale clinical applications are not achievable. Therefore, substantial strategies and research efforts have been devoted to increasing cellular secretion rates of EVs. This review describes various studies exploring different methods to increase the cellular production of EVs, including the application of electrical stimulus, pharmacologic agents, electromagnetic waves, sound waves, shear stress, cell starvation, alcohol, pH, heat, and genetic manipulation. These methods have shown success in increasing EV production, but careful consideration must be given as many of these strategies may alter EV properties and functionalities, and the exact mechanisms causing the increase in cellular production of EVs is generally unknown. Additionally, the methods' effectiveness in increasing EV secretion may diverge with different cell lines and conditions. Further advancements to enhance EV biogenesis secretion for therapeutic development is still a significant need in the field.

Spontaneously Right-Side-Out-Orientated Coupling-Driven ROS-Sensitive Nanoparticles on Cell Membrane Inner Leaflet for Efficient Renovation in Vascular Endothelial Injury

Biomimetic cell membrane camouflaged technology has drawn extensive attention as a feasible and efficient way to realize the biological functions of nanoparticles from the parent cells. As the burgeoning nanotherapeutic, the right-side-out orientation self-assembly and pathological dependent "on-demand" cargo release of cell membrane camouflaged nanocarriers remarkably limit further development for practical applications. In the present study, a spontaneously right-side-out-orientated coupling-driven ROS-sensitive nanotherapeutic has been constructed for target endothelial cells (ECs) repair through the synergistic effects of spontaneously right-side-out-orientated camouflaging. This condition results from the specific affinity between the intracellular domain of key transmembrane receptors band 3 on cell membrane inner leaflet and the corresponding P4.2 peptide-modified nanoparticles without the additional coextrusion. The "on-demand" cargo release results from the pathological ROS-cleavable prodrug. Particularly, the red blood cell camouflaged nanotherapeutics (RBC-LVTNPs) can enhance target drug delivery through low oscillatory shear stress (LSS) blood flow in the injured ECs lesion. Both in vitro and in vivo results collectively confirm that RBC-LVTNPs can restore the damaged ECs and function with the recovered vascular permeability and low inflammation microenvironment. The findings provide a powerful and universal approach for developing the biomimetic cell membrane camouflaged nanotechnology.

Extracellular Vesicles as Biomarkers and Therapeutics for Inflammatory Eye Diseases

Extracellular vesicles (EVs) are a group of cell-derived membrane vesicles of varying sizes that can be secreted by most cells. Depending on the type of cell they are derived from, EVs may contain a variety of cargo including proteins, lipids, miRNA, and DNA. Functionally, EVs play important roles in physiological and pathological processes through intercellular communication. While there has already been significant literature on the involvement of EVs in neurological and cardiovascular disease as well as cancer, recent evidence suggests that EVs may also play a role in mediating inflammatory eye diseases. This paper summarizes current advancements in ocular EV research as well as new ways by which EVs may be utilized as novel biomarkers of or therapeutics for inflammatory eye diseases.

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.

Current perspectives on clinical use of exosomes as novel biomarkers for cancer diagnosis

Exosomes are a heterogeneous subset of extracellular vesicles (EVs) that biogenesis from endosomes. Besides, exosomes contain a variety of molecular cargoes including proteins, lipids and nucleic acids, which play a key role in the mechanism of exosome formation. Meanwhile, exosomes are involved with physiological and pathological conditions. The molecular profile of exosomes reflects the type and pathophysiological status of the originating cells so could potentially be exploited for diagnostic of cancer. This review aims to describe important molecular cargoes involved in exosome biogenesis. In addition, we highlight exogenous factors, especially autophagy, hypoxia and pharmacology, that regulate the release of exosomes and their corresponding cargoes. Particularly, we also emphasize exosome molecular cargoes as potential biomarkers in liquid biopsy for diagnosis of cancer.

Citicoline Modifies the Expression of Specific miRNAs Related to Cardioprotection in Patients with ST-Segment Elevation Myocardial Infarction Subjected to Coronary Angioplasty

Extracellular vesicles are recognized as signaling mediators between cells both in physiological and pathological communication. In this work, we explored the potential effect of citicoline to modify relevant proteins or miRNAs for cardioprotection in the smallest population of such microvesicles; i.e., in exosomes from patients diagnosed with ST-segment elevation myocardial infarction (STEMI) undergoing coronary angioplasty. The plasma-exosome-enriched fraction from these patients was characterized. Their cellular origin was assessed by flow cytometry and Western blot, whereas miRNA expression was evaluated by real-time polymerase chain reaction (qRT-PCR). The content of caveolin-1, caveolin-3, and hnRNPA2B1, which play a relevant role in selective transport of miRNAs into microvesicles, along with the effect on cell viability of the exosomes obtained from citicoline-treated and untreated groups were also analyzed. Our results showed that hypoxic stress increases exosome release into the circulation. Moreover, we found that CD146+ increased in exosomes from citicoline-treated patients, while CD142+ decreased in these patients compared to the placebo group. No changes were detected in the protein levels of caveolin-1, caveolin-3, and hnRNPA2B1. Citicoline administration modified the expression of miR233-3p, miR92, and miR21-5p in exosomes. Cell viability decreased in the presence of exosomes from infarcted patients, while incubation of H9c2 cells with exosomes from patients reperfused with citicoline did not affect cell viability. In conclusion, citicoline administration modifies the expression of specific miRNAs related to cardioprotection in exosomes.

Tumor-Derived Membrane Vesicles: A Promising Tool for Personalized Immunotherapy

Tumor-derived membrane vesicles (TDMVs) are non-invasive, chemotactic, easily obtained characteristics and contain various tumor-borne substances, such as nucleic acid and proteins. The unique properties of tumor cells and membranes make them widely used in drug loading, membrane fusion and vaccines. In particular, personalized vectors prepared using the editable properties of cells can help in the design of personalized vaccines. This review focuses on recent research on TDMV technology and its application in personalized immunotherapy. We elucidate the strengths and challenges of TDMVs to promote their application from theory to clinical practice.

Reinfection of Transplanted Livers in HCV- and HCV/HIV-Infected Patients Is Characterized by a Different MicroRNA Expression Profile

Background: After liver transplantation, HCV/HIV co-infected patients present, compared to the HCV mono-infected ones, increased HCV viral load, rapid progression to liver fibrosis and higher mortality. Liver biopsies (LB), obtained routinely 6 months after transplantation, represent a unique model to assess the early events related to graft re-infection. Here, we used miRNA sequencing of LB obtained from both HCV-and HCV/HIV-infected recipients, to identify transcriptional profiles able to explain the more severe outcome of these latter. Methods: miRNAs of 3 healthy livers, 3 HCV-LB and 3 HCV/HIV-LB were sequenced by Illumina HiSeq2500 platform. The DIANA-miRPath v3.0 webserver and DIANA-microT-CDS algorithm (v5.0) were used to characterize the functions of differentially expressed (DE-) miRNAs, querying the KEGG and Gene Ontology-Biological Process databases. Results: LB obtained from infected patients were characterized, with respect to controls, by a miRNA profile related to viral infection, immune system signaling and DNA damage in HCV-induced carcinogenesis. Instead, HCV-LB and HCV/HIV-LB differed in the expression of miRNAs involved in immunological and apoptotic processes and in extracellular matrix remodeling. Conclusions: liver reinfection processes are associated with early miRNA changes. Further studies are necessary to establish their prognostic role and possible actionability.

Exploring New Kingdoms: The Role of Extracellular Vesicles in Oxi-Inflamm-Aging Related to Cardiorenal Syndrome

The incidence of age associated chronic diseases has increased in recent years. Although several diverse causes produce these phenomena, abundant evidence shows that oxidative stress plays a central role. In recent years, numerous studies have focused on elucidating the role of oxidative stress in the development and progression of both aging and chronic diseases, opening the door to the discovery of new underlying mechanisms and signaling pathways. Among them, senolytics and senomorphics, and extracellular vesicles offer new therapeutic strategies to slow the development of aging and its associated chronic diseases by decreasing oxidative stress. In this review, we aim to discuss the role of extracellular vesicles in human cardiorenal syndrome development and their possible role as biomarkers, targets, or vehicles of drugs to treat this syndrome.

Circulatory exosomal tRF-Glu-CTC-005 and tRF-Gly-GCC-002 serve as predictive factors of successful microdissection testicular sperm extraction in patients with nonobstructive azoospermia

OBJECTIVE

To identify circulating plasma exosomal transfer RNA-derived fragments (tRFs) as the predictive factors of successful microdissection testicular sperm extraction (micro-TESE) in patients with nonobstructive azoospermia (NOA).

DESIGN

Case and control prospective study.

SETTING

Academic research laboratory.

PATIENT(S)

Twelve patients with NOA with successful sperm retrieval by micro-TESE, 18 patients with NOA with failed sperm retrieval by micro-TESE, and 12 normozoospermic fertile controls.

INTERVENTION(S)

Blood samples were collected from participants.

MAIN OUTCOME MEASURE(S)

The abundance of tRFs normalized as counts per million of the total aligned reads with the next-generation sequencing system; candidate tRF levels were validated through quantitative reverse transcription polymerase chain reaction; predictive accuracy was evaluated by the receiver operating characteristic area under the curve analysis. The nomogram was built for ranking.

RESULT(S)

The plasma circulating exosomal tRF-Gly-GCC-002 and tRF-Glu-CTC-005 manifested the most confident differential expression between patients with NOA with successful sperm retrieval by micro-TESE and patients with NOA with failed sperm retrieval by micro-TESE. The target gene prediction of these 2 tRFs followed by the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis indicated the functional enrichment of neuroendocrine protein metabolism and striatum/subpallium development. The herpes simplex virus 1 infection pathway was also involved. The receiver operating characteristic area under the curve (AUC) analysis demonstrated a promising predictive accuracy: tRF-Gly-GCC-002, AUC of 0.921, and tRF-Glu-CTC-005, AUC of 0.954. A regression model was built and presented with the nomogram for further assessment.

CONCLUSION(S)

This study described the exosomal tRF-Gly-GCC-002 and tRF-Glu-CTC-005 expression values, indicated a promising predictive effect for accessibility of sperm retrieval through micro-TESE from patients with NOA, and highlighted tRF-Gly-GCC-002 and tRF-Glu-CTC-005 as useful biomarkers in patients with NOA seeking in vitro conception with their residual sperm.

Impact of native and external factors on exosome release: understanding reactive exosome secretion and its biogenesis

Exosomes are minuscule vesicles secreted in the endolytic region of most mammalian cells. The release of exosomes from the cell engenders cell-to-cell signaling between cellular-compartments. The trading of exosomes between tumor and yonder cells plays a hypercritical role in tumor growth and progression. The exosome released from each tumor cell sequestrates a unique biogenetic pathway reflecting its cellular origin depending on the tumor type. However, treatment of tumor cells with certain physiological factors like drugs, chemotherapy, radiation, etc., enhance the release of exosomes and alters its biogenetic pathway compared with untreated tumor cells. In this review, we will discuss how the non-native physiological factors influence the release of exosomes and how these reactive exosomes orchestrate a unique patterning of a cargo sorting mechanism. We will also discuss the role of reactively secreted exosomes in mediating tumor metastasis, angiogenesis, and tumor progression.

Extracellular Vesicles from Mycoplasmas Can Penetrate Eukaryotic Cells In Vitro and Modulate the Cellular Proteome

The extracellular vesicles (EVs) produced by bacteria transport a wide range of compounds, including proteins, DNA and RNA, mediate intercellular interactions, and may be important participants in the mechanisms underlying the persistence of infectious agents. This study focuses on testing the hypothesis that the EVs of mycoplasmas, the smallest prokaryotes capable of independent reproduction, combined in the class referred to as Mollicutes, can penetrate into eukaryotic cells and modulate their immunoreactivity. To verify this hypothesis, for the first time, studies of in vitro interaction between human skin fibroblasts and vesicles isolated from Acholeplasma laidlawii (the ubiquitous mycoplasma that infects higher eukaryotes and is the main contaminant of cell cultures and vaccines) were conducted using confocal laser scanning microscopy and proteome profiling, employing a combination of 2D-DIGE and MALDI-TOF/TOF, the Mascot mass-spectrum analysis software and the DAVID functional annotation tool. These studies have revealed for the first time that the extracellular vesicles of A. laidlawii can penetrate into eukaryotic cells in vitro and modulate the expression of cellular proteins. The molecular mechanisms behind the interaction of mycoplasma vesicles with eukaryotic cells and the contribution of the respective nanostructures to the molecular machinery of cellular permissiveness still remain to be elucidated. The study of these aspects is relevant both for fundamental research into the "logic of life" of the simplest prokaryotes, and the practical development of efficient control over hypermutable bacteria infecting humans, animals and plants, as well as contaminating cell cultures and vaccines.

Exosomes as Smart Nanoplatforms for Diagnosis and Therapy of Cancer

Exosomes are composed of a lipid bilayer membrane, containing proteins, nucleic acids, DNA, RNA, etc., derived from donor cells. They have a size range of approximately 30-150 nm. The intrinsic characteristics of exosomes, including efficient cellular uptake, low immunogenicity, low toxicity, intrinsic ability to traverse biological barriers, and inherent targeting ability, facilitate their application to the drug delivery system. Here, we review the generation, uptake, separation, and purification methods of exosomes, focusing on their application as carriers in tumor diagnosis and treatment, especially in brain tumors, as well as the patent applications of exosomes in recent years.

EV Cargo Sorting in Therapeutic Development for Cardiovascular Disease

Cardiovascular disease remains the leading cause of morbidity and mortality in the world. Thus, therapeutic interventions to circumvent this growing burden are of utmost importance. Extracellular vesicles (EVs) actively secreted by most living cells, play a key role in paracrine and endocrine intercellular communication via exchange of biological molecules. As the content of secreted EVs reflect the physiology and pathology of the cell of their origin, EVs play a significant role in cellular homeostasis, disease pathogenesis and diagnostics. Moreover, EVs are gaining popularity in clinics as therapeutic and drug delivery vehicles, transferring bioactive molecules such as proteins, genes, miRNAs and other therapeutic agents to target cells to treat diseases and deter disease progression. Despite our limited but growing knowledge of EV biology, it is imperative to understand the complex mechanisms of EV cargo sorting in pursuit of designing next generation EV-based therapeutic delivery systems. In this review, we highlight the mechanisms of EV cargo sorting and methods of EV bioengineering and discuss engineered EVs as a potential therapeutic delivery system to treat cardiovascular disease.

Characterization of the exosomes in the allantoic fluid of the chicken embryo

The embryo stage is critical for chicken development. Numerous studies have been conducted to clarify the dynamic changes and functions of various proteins and the composition of amino acids during embryo development. However, the physiological characteristics of extraembryonic fluid (allantoic and amniotic), especially allantoic fluid (AF), remain largely unexplored; furthermore, how information is transmitted from embryonic fluid is unknown. In this study, AF-derived exosomes ranging from 60 to 160 nm in diameter from fertilized eggs at 13 d of incubation of fast-growth chickens (WG chicken), medium-growth chickens (Silky N4 chicken), and slow-growth chickens (Huiyang Beard chicken) were isolated and purified by different ultra-centrifugations and further verified by transmission electron microscopy and a flow nano-analyzer. Expression of the exosomal positive biomarkers of ALIX and HSP70 as well as lack of the epithelium marker GRP78 was observed by Western blotting. In addition, small RNA sequencing revealed that AF-derived exosomes at 13 d of incubation contained a large number of known miRNAs (32.62%–65.83%). The top 10 most abundant and co-expressed miRNAs were primarily related to development, growth, and immunity. In addition, AF-derived exosomes promoted DF-1 cell migration. These findings broadened our understanding of the characteristic of AF-derived exosomes.

Confocal Blood Flow Videomicroscopy of Thrombus Formation over Human Arteries and Local Targeting of P2X7

Atherothrombosis exposes vascular components to blood. Currently, new antithrombotic therapies are emerging. Herein we investigated thrombogenesis of human arteries with/without atherosclerosis, and the interaction of coagulation and vascular components, we and explored the anti-thrombogenic efficacy of blockade of the P2X purinoceptor 7 (P2X7). A confocal blood flow videomicroscopy system was performed on cryosections of internal mammary artery (IMA) or carotid plaque (CPL) determining/localizing platelets and fibrin. Blood from healthy donors elicited thrombi over arterial layers. Confocal microscopy associated thrombus with tissue presence of collagen type I, laminin, fibrin(ogen) and tissue factor (TF). The addition of antibodies blocking TF (aTF) or factor XI (aFXI) to blood significantly reduced fibrin deposition, variable platelet aggregation and aTF + aFXI almost abolished thrombus formation, showing synergy between coagulation pathways. A scarce effect of aTF over sub-endothelial regions, more abundant in tissue TF and bundles of laminin and collagen type I than deep intima, may suggest tissue thrombogenicity as molecular structure-related. Consistently with TF-related vascular function and expression of P2X7, the sections from CPL but not IMA tissue cultures pre-treated with the P2X7 antagonist A740003 demonstrated poor thrombogenesis in flow experiments. These data hint to local targeting studies on P2X7 modulation for atherothrombosis prevention/therapy.

Extracellular Vesicle-Based Therapeutics for Heart Repair

Extracellular vesicles (EVs) are constituted by a group of heterogeneous membrane vesicles secreted by most cell types that play a crucial role in cell–cell communication. In recent years, EVs have been postulated as a relevant novel therapeutic option for cardiovascular diseases, including myocardial infarction (MI), partially outperforming cell therapy. EVs may present several desirable features, such as no tumorigenicity, low immunogenic potential, high stability, and fine cardiac reparative efficacy. Furthermore, the natural origin of EVs makes them exceptional vehicles for drug delivery. EVs may overcome many of the limitations associated with current drug delivery systems (DDS), as they can travel long distances in body fluids, cross biological barriers, and deliver their cargo to recipient cells, among others. Here, we provide an overview of the most recent discoveries regarding the therapeutic potential of EVs for addressing cardiac damage after MI. In addition, we review the use of bioengineered EVs for targeted cardiac delivery and present some recent advances for exploiting EVs as DDS. Finally, we also discuss some of the most crucial aspects that should be addressed before a widespread translation to the clinical arena.

Profiling Inflammatory Extracellular Vesicles in Plasma and Cerebrospinal Fluid: An Optimized Diagnostic Model for Parkinson's Disease

Extracellular vesicles (EVs) play a central role in intercellular communication, which is relevant for inflammatory and immune processes implicated in neurodegenerative disorders, such as Parkinson's Disease (PD). We characterized and compared distinctive cerebrospinal fluid (CSF)-derived EVs in PD and atypical parkinsonisms (AP), aiming to integrate a diagnostic model based on immune profiling of plasma-derived EVs via artificial intelligence. Plasma- and CSF-derived EVs were isolated from patients with PD, multiple system atrophy (MSA), AP with tauopathies (AP-Tau), and healthy controls. Expression levels of 37 EV surface markers were measured by a flow cytometric bead-based platform and a diagnostic model based on expression of EV surface markers was built by supervised learning algorithms. The PD group showed higher amount of CSF-derived EVs than other groups. Among the 17 EV surface markers differentially expressed in plasma, eight were expressed also in CSF of a subgroup of PD, 10 in MSA, and 6 in AP-Tau. A two-level random forest model was built using EV markers co-expressed in plasma and CSF. The model discriminated PD from non-PD patients with high sensitivity (96.6%) and accuracy (92.6%). EV surface marker characterization bolsters the relevance of inflammation in PD and it underscores the role of EVs as pathways/biomarkers for protein aggregation-related neurodegenerative diseases.

Similarities and Differences in Extracellular Vesicle Profiles between Ischaemic Stroke and Myocardial Infarction

Extracellular vesicles (EVs) are involved in intercellular signalling through the transfer of molecules during physiological and pathological conditions, such as ischaemic disease. EVs might therefore play a role in ischaemic stroke (IS) and myocardial infarction (MI). In the present study, we analysed the similarities and differences in the content of circulating EVs in patients with IS and MI. This prospective observational study enrolled 140 participants (81 patients with IS, 37 with MI and 22 healthy controls [HCs]). We analysed the protein and microRNA content from EVs using proteomics and reverse transcription quantitative real-time polymerase chain reaction and compared it between the groups. In the patients with IS and MI, we identified 14 common proteins. When comparing IS and MI, we found differences in the protein profiles (apolipoprotein B, alpha-2-macroglobulin, fibronectin). We also found lower levels of miR-340 and miR-424 and higher levels of miR-29b in the patients with IS and MI compared with the HCs. Lastly, we found higher miR-340 levels in IS than in MI. In conclusion, proteomic and miRNA analyses suggest a relationship between circulating EV content and the patient’s disease state. Although IS and MI affect different organs (brain and heart) with distinct histological characteristics, certain EV proteins and miRNAs appear to participate in both diseases, while others are present only in patients with IS.

Through the back door: Unconventional protein secretion

Proteins are secreted from eukaryotic cells by several mechanisms besides the well-characterized classical secretory system. Proteins destined to enter the classical secretory system contain a signal peptide for translocation into the endoplasmic reticulum. However, many proteins lacking a signal peptide are secreted nonetheless. Contrary to conventional belief, these proteins are not just released as a result of membrane damage leading to cell leakage, but are actively packaged for secretion in alternative pathways. They are called unconventionally secreted proteins, and the best-characterized are from fungi and mammals. These proteins have extracellular functions including cell signaling, immune modulation, as well as moonlighting activities different from their well-described intracellular functions. Among the pathways for unconventional secretion are direct transfer across the plasma membrane, release within plasma membrane-derived microvesicles, use of elements of autophagy, or secretion from endosomal/multivesicular body-related components. We review the fungal and metazoan unconventional secretory pathways and their regulation, and propose experimental criteria to identify their mode of secretion.

Extracellular Endothelial Cell-Derived Vesicles: Emerging Role in Cardiac and Vascular Remodeling in Heart Failure

Extracellular vesicles play a pivotal role in numerous physiological (immune response, cell-to-cell cooperation, angiogenesis) and pathological (reparation, inflammation, thrombosis/coagulation, atherosclerosis, endothelial dysfunction) processes. The development of heart failure is strongly associated with endothelial dysfunction, microvascular inflammation, alteration in tissue repair, and cardiac and vascular remodeling. It has been postulated that activated endothelial cell-derived vesicles are not just transfer forms of several active molecules (such as regulatory peptides, coagulation factors, growth factors, active molecules, hormones that are embedded onto angiogenesis, tissue reparation, proliferation, and even prevention from ischemia/hypoxia), but are instead involved in direct myocardial and vascular damage due to regulation of epigenetic responses of the tissue. These responses are controlled by several factors, such as micro-RNAs, that are transferred inside extracellular vesicles from mother cells to acceptor cells and are transductors of epigenetic signals. Finally, it is not a uniform opinion whether different phenotypes of heart failure are the result of altered cardiac and vascular reparation due to certain epigenetic responses, which are yielded by co-morbidities, such as diabetes mellitus and obesity. The aim of the review is to summarize knowledge regarding the role of various types of extracellular endothelial cell-derived vesicles in the regulation of cardiac and vascular remodeling in heart failure.

The biology function and biomedical applications of exosomes

The study of extracellular vesicles (EVs) has the potential to identify unknown cellular and molecular mechanisms in intercellular communication and in organ homeostasis and disease. Exosomes, with an average diameter of ~100 nanometers, are a subset of EVs. The biogenesis of exosomes involves their origin in endosomes, and subsequent interactions with other intracellular vesicles and organelles generate the final content of the exosomes. Their diverse constituents include nucleic acids, proteins, lipids, amino acids, and metabolites, which can reflect their cell of origin. In various diseases, exosomes offer a window into altered cellular or tissue states, and their detection in biological fluids potentially offers a multicomponent diagnostic readout. The efficient exchange of cellular components through exosomes can inform their applied use in designing exosome-based therapeutics.

Infarct Zone: a Novel Platform for Exosome Trade in Cardiac Tissue Regeneration

The global incidence of coronary artery diseases (CADs), especially myocardial infarction (MI), has drastically increased in recent years. Even though the conventional therapies have improved the outcomes, the post-MI complications and the increased rate of recurrence among the survivors are still alarming. Molecular events associated with the pathogenesis and the adaptive responses of the surviving myocardium are largely unknown. Focus on exosome-mediated signaling for cell-cell/matrix communications at the infarct zone reflects an emerging opportunity in cardiac regeneration. Also, cardiac tissue engineering provides promising insights for the next generation of therapeutic approaches in the management of CADs. In this article, we critically reviewed the current understanding on the biology of cardiac exosomes, therapeutic potential of exosomes, and recent developments in cardiac tissue engineering and discussed novel translational approaches based on tissue engineering and exosomes for cardiac regeneration and CADs.

Brain-Derived Extracellular Vesicle microRNA Signatures Associated with In Utero and Postnatal Oxycodone Exposure

Oxycodone (oxy) is a semi-synthetic opioid commonly used as a pain medication that is also a widely abused prescription drug. While very limited studies have examined the effect of in utero oxy (IUO) exposure on neurodevelopment, a significant gap in knowledge is the effect of IUO compared with postnatal oxy (PNO) exposure on synaptogenesis—a key process in the formation of synapses during brain development—in the exposed offspring. One relatively unexplored form of cell–cell communication associated with brain development in response to IUO and PNO exposure are extracellular vesicles (EVs). EVs are membrane-bound vesicles that serve as carriers of cargo, such as microRNAs (miRNAs). Using RNA-Seq analysis, we identified distinct brain-derived extracellular vesicle (BDEs) miRNA signatures associated with IUO and PNO exposure, including their gene targets, regulating key functional pathways associated with brain development to be more impacted in the IUO offspring. Further treatment of primary 14-day in vitro (DIV) neurons with IUO BDEs caused a significant reduction in spine density compared to treatment with BDEs from PNO and saline groups. In summary, our studies identified for the first time, key BDE miRNA signatures in IUO- and PNO-exposed offspring, which could impact their brain development as well as synaptic function.

PAHs increase the production of extracellular vesicles both in vitro in endothelial cells and in vivo in urines from rats

Environmental contaminants, to which humans are widely exposed, cause or worsen several diseases, like cardiovascular diseases and cancers. Among these molecules, polycyclic aromatic hydrocarbons (PAHs) stand out since they are ubiquitous pollutants found in ambient air and diet. Because of their toxic effects, public Health agencies promote development of research studies aiming at increasing the knowledge about PAHs and the discovery of biomarkers of exposure and/or effects. Extracellular vesicles (EVs), including small extracellular vesicles (S-EVs or exosomes) and large extracellular vesicles (L-EVs or microvesicles), are delivery systems for multimolecular messages related to the nature and status of the originating cells. Because they are produced by all cells and detected within body fluids, EV releases could act as cell responses and thereby serve as biomarkers. To test whether EVs can serve as biomarkers of PAHs exposure, we evaluate the effects of these pollutants on EV production using an in vitro approach (human endothelial cell line, HMEC-1) and an in vivo approach (urine samples from PAHs-exposed rats). Our study indicates that, i) PAH exposure increases in vitro the EV production by endothelial cells and in vivo the release of EVs in urine, and that the stimulating effects of PAHs concern both S-EVs and L-EVs; ii) PAH exposure and more particularly exposure to B[a]P, can influence the composition of exosomes produced by endothelial cells; iii) the aryl hydrocarbon receptor, a cytosolic receptor associated to most deleterious effects of PAHs, would be involved in the PAH effects on the release of S-EVs, but not L-EVs. These results suggest that EVs may have utility for monitoring exposure to PAHs, and more particularly to B[a]P, considered as reference PAH, and to detect the related early cellular response prior to end-organ damages.

Role of Exosomes in Central Nervous System Diseases

There are many types of intercellular communication, and extracellular vesicles are one of the important forms of this. They are released by a variety of cell types, are heterogeneous, and can roughly be divided into microvesicles and exosomes according to their occurrence and function. Of course, exosomes do not just play a role in cell-to-cell communication. In the nervous system, exosomes can participate in intercellular communication, maintain the myelin sheath, and eliminate waste. Similarly, exosomes in the brain can play a role in central nervous system diseases, such as stroke, Alzheimer's disease (AD), Parkinson's disease (PD), prion disease, and traumatic encephalopathy (CTE), with both positive and negative effects (such as the transfer of misfolded proteins). Exosomes contain a variety of key bioactive substances and can therefore be considered as a snapshot of the intracellular environment. Studies have shown that exosomes from the central nervous system can be found in cerebrospinal fluid and peripheral body fluids, and that their contents will change with disease occurrence. Because exosomes can penetrate the blood brain barrier (BBB) and are highly stable in peripheral circulation, they can protect disease-related molecules well and therefore, using exosomes as a biomarker of central nervous system diseases is an attractive prospect as they can be used to monitor disease development and enable early diagnosis and treatment optimization. In this review, we discuss the current state of knowledge of exosomes, and introduce their pathophysiological roles in different diseases of the central nervous system as well as their roles and applications as a viable pathological biomarker.

Ultrasound Facilitates Naturally Equipped Exosomes Derived from Macrophages and Blood Serum for Orthotopic Glioma Treatment

Exosomes (Exos) are endogenous nanocarriers that have utility as novel delivery systems for the treatment of brain cancers. However, in general, natural Exos show limited BBB-crossing capacity and lack specific targeting. Further modifications including targeting peptides and genetic engineering approaches can circumvent these issues, but the process is time-consuming. Focused ultrasound (FUS) has been approved by the Food and Drug Administration for the diagnosis and treatment of brain diseases due to its noninvasive nature, reversibility, and instantaneous local opening of the BBB. In this study, we developed a natural and safe transportation system using FUS to increase the targeted delivery of Exos for glioma therapy. We also compared the advantages of macrophage-derived Exos (R-Exos) and blood serum-derived Exos (B-Exos) to screen for an improved platform with scope for clinical transformation. In vitro, both R-Exos and B-Exos were transported through BBB models and accumulated in glioma cells with the assistance of ultrasound exposure. R-Exos and B-Exos displayed no obvious differences in physical characteristics, drug release, tumor targeting, and cytotoxicity when combined with FUS. In vivo animal imaging studies suggested that the fluorescence intensity of B-Exos plus single FUS in brains was 4.45-fold higher than that of B-Exos alone. Furthermore, B-Exos plus twice FUS treatment efficiently suppressed glioma growth with no obvious side effects. We therefore demonstrate that the combination of FUS and naturally abundant B-Exos is a potent strategy for brain cancer therapeutics.