Exosomal cargos modulate autophagy in recipient cells via different signaling pathways

Anti-aging based on stem cell therapy: A scoping review

Stem cells are present in the tissues and organs and remain in a quiescent and undifferentiated state until it is physiologically necessary to produce new descendant cells. Due to their multipotency property, mesenchymal stem cells have attracted considerable attention worldwide due to their immunomodulation and therapeutic function in tissue regeneration. Stem cells secrete components such as paracrine factors, extracellular vesicles, and exosomes which have been shown to have anti-inflammatory, anti-aging, reconstruction and wound healing potentials in many in vitro and in vivo models. The pluripotency and immunomodulatory features of stem cells could potentially be an effective tool in cell therapy and tissue repair. Aging affects the capacity for self-renewal and differentiation of stem cells, decreasing the potential for regeneration and the loss of optimal functions in organisms over time. Current progress in the field of cellular therapy and regenerative medicine has facilitated the evolution of particular guidelines and quality control approaches, which eventually lead to clinical trials. Cell therapy could potentially be one of the most promising therapies to control aging due to the fact that single stem cell transplantation can regenerate or substitute the injured tissue. To understand the involvement of stem cells not only in tissue maintenance and disease but also in the control of aging it is important to know and identify their properties, functions, and regulation in vivo, which are addressed in this review.

Unignored intracellular journey and biomedical applications of extracellular vesicles

The intracellular journey of extracellular vesicles (EVs) cannot be ignored in various biological pathological processes. In this review, the biogenesis, biological functions, uptake pathways, intracellular trafficking routes, and biomedical applications of EVs were highlighted. Endosomal escape is a unique mode of EVs release. When vesicles escape from endosomes, they avoid the fate of fusing with lysosomes and being degraded, thus having the opportunity to directly enter the cytoplasm or other organelles. This escape mechanism is crucial for EVs to deliver specific signals or substances. The intracellular trafficking of EVs after endosomal escape is a complex and significant biological process that involves the coordinated work of various cellular structures and molecules. Through the in-depth study of this process, the function and regulatory mechanism of EVs are fully understood, providing new dimensions for future biomedical diagnosis and treatment.

Exosomes as therapeutic and drug delivery vehicle for neurodegenerative diseases

Neurodegenerative disorders are complex, progressive, and life-threatening. They cause mortality and disability for millions of people worldwide. Appropriate treatment for neurodegenerative diseases (NDs) is still clinically lacking due to the presence of the blood-brain barrier (BBB). Developing an effective transport system that can cross the BBB and enhance the therapeutic effect of neuroprotective agents has been a major challenge for NDs. Exosomes are endogenous nano-sized vesicles that naturally carry biomolecular cargoes. Many studies have indicated that exosome content, particularly microRNAs (miRNAs), possess biological activities by targeting several signaling pathways involved in apoptosis, inflammation, autophagy, and oxidative stress. Exosome content can influence cellular function in healthy or pathological ways. Furthermore, since exosomes reflect the features of the parental cells, their cargoes offer opportunities for early diagnosis and therapeutic intervention of diseases. Exosomes have unique characteristics that make them ideal for delivering drugs directly to the brain. These characteristics include the ability to pass through the BBB, biocompatibility, stability, and innate targeting properties. This review emphasizes the role of exosomes in alleviating NDs and discusses the associated signaling pathways and molecular mechanisms. Furthermore, the unique biological features of exosomes, making them a promising natural transporter for delivering various medications to the brain to combat several NDs, are also discussed.

Platelet-derived exosomes regulate endothelial cell inflammation and M1 macrophage polarization in coronary artery thrombosis via modulating miR-34a-5p expression

As the important factors in coronary artery thrombosis, endothelial injury and M1 macrophage polarization are closely related to the expression of miR-34a-5p. Exosomes in plasma are mainly derived from platelets and play an important role in thrombosis. Based on these facts, this study was conducted to investigate the acting mechanism of platelet-derived exosomes (PLT-exo) in the effects of endothelial injury and M1 macrophage polarization on coronary artery thrombosis. Firstly, rats were divided into the sham-operated group and the coronary microembolization (CME) group, and their plasma-derived exosomes were extracted to detect the expression of miR-34a-5p. Next, the PLT-exo were extracted from healthy volunteers and then co-cultured with ox-LDL-induced endothelial cells and LPS-induced macrophages, respectively. Subsequently, the expression of IL-1β, IL-6, TNF-α, and ICAM-1 in endothelial cells was measured, and the level of markers related to M1 macrophage polarization and Sirt1/NF-κB pathway was detected. Finally, the above indicators were examined again after PLT-exo combined with miR-34a-5p mimic were co-cultured with endothelial cells and macrophages, respectively. The results demonstrated that the expression of miR-34a-5p in the CME group was up-regulated compared with the sham-operated group. In cell experiments, PLT-exo modulated the Sirt1/NF-κB pathway by inhibiting the expression of intracellular miR-34a-5p and down-regulated the expression of IL-1β, IL-6, TNF-α, and ICAM-1 in endothelial cells and M1 macrophage polarization. After the transfection with miR-34a-5p mimic, endothelial cell inflammatory injury and M1 macrophage polarization increased to varying degrees. In conclusion, PLT-exo can alleviate coronary artery thrombosis by reducing endothelial cell inflammation and M1 macrophage polarization via inhibiting miR-34a-5p expression. In contrast, miR-34a-5p overexpression in PLT-exo may exacerbate these pathological injuries in coronary artery thrombosis.

miR-584-5p / Ykt6 - mediated autophagy - lysosome - exosome pathway as a critical route affecting the toxic effects of lead on HK-2 cells

Lead is a widespread environmental pollutant with serious adverse effects on human health, but the mechanism underlying its toxicity remains elusive. This study aimed to investigate the role of miR-584-5p / Ykt6 axis in the toxic effect of lead on HK-2 cells and the related mechanism. Our data suggested that lead exposure caused significant cytotoxicity, DNA and chromosome damage to HK-2 cells. Mechanistically, lead exposure down-regulated miR-584-5p and up-regulated Ykt6 expression, consequently, autophagosomal number and autophagic flux increased, lysosomal number and activity decreased, exosomal secretion increased. Interestingly, when miR-584-5p level was enhanced with mimic, autophagosomal number and autophagic flux decreased, lysosomal number and activity increased, ultimately, exosomal secretion was down-regulated, which resulted in significant aggravated toxic effects of lead. Further, directly blocking exosomal secretion with inhibitor GW4869 also resulted in exacerbated toxic effects of lead. Herein, we conclude that miR-584-5p / Ykt6 - mediated autophagy - lysosome - exosome pathway may be a critical route affecting the toxic effects of lead on HK-2 cells. We provide a novel insight into the mechanism underlying the toxicity of lead on human cells.

Inflammation and Exosomes in Fabry Disease Pathogenesis

Fabry Disease (FD) is one of the most prevalent lysosomal storage disorders, resulting from mutations in the GLA gene located on the X chromosome. This genetic mutation triggers glo-botriaosylceramide (Gb-3) buildup within lysosomes, ultimately impairing cellular functions. Given the role of lysosomes in immune cell physiology, FD has been suggested to have a profound impact on immunological responses. During the past years, research has been focusing on this topic, and pooled evidence strengthens the hypothesis that Gb-3 accumulation potentiates the production of pro-inflammatory mediators, revealing the existence of an acute inflammatory process in FD that possibly develops to a chronic state due to stimulus persistency. In parallel, extracellular vesicles (EVs) have gained attention due to their function as intercellular communicators. Considering EVs' capacity to convey cargo from parent to distant cells, they emerge as potential inflammatory intermediaries capable of transporting cytokines and other immunomodulatory molecules. In this review, we revisit the evidence underlying the association between FD and altered immune responses and explore the potential of EVs to function as inflammatory vehicles.

The role of exosomes in cancer-related programmed cell death

Cancer arises from the growth and division of uncontrolled erroneous cells. Programmed cell death (PCD), or regulated cell death (RCD), includes natural processes that eliminate damaged or abnormal cells. Dysregulation of PCD is a hallmark of cancer, as cancer cells often evade cell death and continue to proliferate. Exosomes nanoscale extracellular vesicles secreted by different types of cells carrying a variety of molecules, including nucleic acids, proteins, and lipids, to have indispensable role in the communication between cells, and can influence various cellular processes, including PCD. Exosomes have been shown to modulate PCD in cancer cells by transferring pro- or antideath molecules to neighboring cells. Additionally, exosomes can facilitate the spread of PCD to surrounding cancer cells, making them promising in the treatment of various cancers. The exosomes' diagnostic potential in cancer is also an active area of research. Exosomes can be isolated from a wide range of bodily fluids and tissues, such as blood and urine, and can provide a noninvasive way to monitor cancer progression and treatment response. Furthermore, exosomes have also been employed as a delivery system for therapeutic agents. By engineering exosomes to carry drugs or other therapeutic molecules, they can be targeted specifically to cancer cells, reducing toxicity to healthy tissues. Here, we discussed exosomes in the diagnosis and prevention of cancers, tumor immunotherapy, and drug delivery, as well as in different types of PCD.

mTOR signalling pathway in stem cell bioactivities and angiogenesis potential

The mammalian target of rapamycin (mTOR) is a protein kinase that responds to different stimuli such as stresses, starvation and hypoxic conditions. The modulation of this effector can lead to the alteration of cell dynamic growth, proliferation, basal metabolism and other bioactivities. Considering this fact, the mTOR pathway is believed to regulate the diverse functions in several cell lineages. Due to the pleiotropic effects of the mTOR, we here, hypothesize that this effector can also regulate the bioactivity of stem cells in response to external stimuli pathways under physiological and pathological conditions. As a correlation, we aimed to highlight the close relationship between the mTOR signalling axis and the regenerative potential of stem cells in a different milieu. The relevant publications were included in this study using electronic searches of the PubMed database from inception to February 2023. We noted that the mTOR signalling cascade can affect different stem cell bioactivities, especially angiogenesis under physiological and pathological conditions. Modulation of mTOR signalling pathways is thought of as an effective strategy to modulate the angiogenic properties of stem cells.

HD-sEVs in bovine follicular fluid regulate granulosa cell apoptosis and estradiol secretion through the autophagy pathway

Follicular fluid (FF) is rich in extracellular vesicles (EVs), which have regulatory effects on follicular growth and oocyte development. EVs can be divided into two subtypes, i.e. HD-sEVs and LD-sEVs. In this study, HD-sEVs were successfully isolated from bovine follicular fluid (BFF) by density gradient ultracentrifugation. By western blot, quantitative polymerase chain reaction (qPCR), flow cytometry, transmission electron microscopy (TEM) and enzyme-linked immunosorbent assay (ELISA), this study found HD-sEVs promoted autophagy in bGCs by increasing the protein and mRNA expression of LC3II/LC3I ratio and Beclin1, and inhibiting the protein and mRNA expression of p62. HD-sEVs promoted mitophagy in bGCs by increasing the protein and mRNA expression of VDAC1, CTSD, and HSP60. Flow cytometry showed that HD-sEVs inhibited bGCs apoptosis rate. HD-sEVs promoted estradiol secretion by increasing steroidogenesis-associated proteins and mRNA, such as CYP19A, HSD3B in bGCs. HD-sEVs promoted autophagosome formation and mitochondrial structure swelling in bGCs, and decreased p-mTOR/mTOR ratio. The above phenomenon was reversed when wortmannin was added. Collectively, BFF HD-sEVs promote bGCs autophagy and mitophagy, inhibit bGCs apoptosis and promote estradiol secretion through the autophagy pathway-mTOR signaling pathway.

Mesenchymal stem cells and their derived exosomes for ALI/ARDS: A promising therapy

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is a serious clinical syndrome with a high morbidity and mortality. Presently, therapeutic approaches for ALI/ARDS primarily revolve around symptomatic supportive care encompassing mechanical ventilation and fluid management. Regrettably, the prognosis for most ALI/ARDS patients remains bleak due to the absence of effective treatment strategies. Even survivors of ALI/ARDS may have long-term pulmonary dysfunction and cognitive impairment. The quality of life has been seriously compromised. The emergence of mesenchymal stem cells (MSCs) and their exosomes has opened up an expansive realm of potential and optimism for addressing the plight of ALI/ARDS patients, as MSCs and their derived exosomes exhibit multifaceted capabilities, including anti-inflammatory properties, facilitation of tissue repair and regeneration, and apoptosis inhibition. Therefore, future research should focus on the possible mechanisms of MSCs and their derived exosomes for the treatment of ALI/ARDS and open up new avenues for their clinical applications.

Application of cell-derived exosomes in the hematological malignancies therapy

Exosomes are small membrane vesicles of endocytic origin that are produced by both tumor and normal cells and can be found in physiological fluids like plasma and cell culture supernatants. They include cytokines, growth factors, proteins, lipids, RNAs, and metabolites and are important intercellular communication controllers in several disorders. According to a vast amount of research, exosomes could support or inhibit tumor start and diffusion in a variety of solid and hematological malignancies by paracrine signaling. Exosomes are crucial therapeutic agents for a variety of illnesses, such as cancer and autoimmune diseases. This review discusses the most current and encouraging findings from in vitro and experimental in vivo research, as well as the scant number of ongoing clinical trials, with a focus on the impact of exosomes in the treatment of malignancies. Exosomes have great promise as carriers of medications, antagonists, genes, and other therapeutic materials that can be incorporated into their core in a variety of ways. Exosomes can also alter the metabolism of cancer cells, alter the activity of immunologic effectors, and alter non-coding RNAs, all of which can alter the tumor microenvironment and turn it from a pro-tumor to an anti-tumor milieu. This subject is covered in the current review, which also looks at how exosomes contribute to the onset and progression of hematological malignancies, as well as their importance in diagnosing and treating these conditions.

The tumor immune microenvironment in pancreatic cancer and its potential in the identification of immunotherapy biomarkers

INTRODUCTION

Pancreatic cancer (PC) has an extremely poor prognosis, even with surgical resection and triplet chemotherapy treatment. Cancer immunotherapy has been recently approved for tumor-agnostic treatment with genome analysis, including in PC. However, it has limited efficacy.

AREAS COVERED

In addition to the low tumor mutation burden, one of the difficulties of immunotherapy in PC is the presence of abundant stromal cells in its microenvironment. Among stromal cells, cancer-associated fibroblasts (CAFs) play a major role in immunotherapy resistance, and CAF-targeted therapies are currently under development, including those in combination with immunotherapies. Meanwhile, microbiomes and tumor-derived exosomes (TDEs) have been shown to alter the behavior of distant receptor cells in PC. This review discusses the role of CAFs, microbiomes, and TDEs in PC tumor immunity.

EXPERT OPINION

Elucidating the mechanisms by which CAFs, microbiomes, and TDEs are involved in the tumorigenesis of PC will be helpful for developing novel immunotherapeutic strategies and identifying companion biomarkers for immunotherapy. Spatial single-cell analysis of the tumor microenvironment will be useful for identifying biomarkers of PC immunity. Furthermore, given the complexity of immune mechanisms, artificial intelligence models will be beneficial for predicting the efficacy of immunotherapy.

Inflammatory stimulation of astrocytes affects the expression of miRNA-22-3p within NSCs-EVs regulating remyelination by targeting KDM3A

BACKGROUND

Endogenous neural stem cells (NSCs) are critical for the remyelination of axons following spinal cord injury (SCI). Cell-cell communication plays a key role in the regulation of the differentiation of NSCs. Astrocytes act as immune cells that encounter early inflammation, forming a glial barrier to prevent the spread of destructive inflammation following SCI. In addition, the cytokines released from astrocytes participate in the regulation of the differentiation of NSCs. The aim of this study was to investigate the effects of cytokines released from inflammation-stimulated astrocytes on the differentiation of NSCs following SCI and to explore the influence of these cytokines on NSC-NSC communication.

RESULTS

Lipopolysaccharide stimulation of astrocytes increased bone morphogenetic protein 2 (BMP2) release, which not only promoted the differentiation of NSCs into astrocytes and inhibited axon remyelination in SCI lesions but also enriched miRNA-22-3p within extracellular vesicles derived from NSCs. These miRNA-22 molecules function as a feedback loop to promote NSC differentiation into oligodendrocytes and the remyelination of axons following SCI by targeting KDM3A.

CONCLUSIONS

This study revealed that by releasing BMP2, astrocytes were able to regulate the differentiation of NSCs and NSC-NSC communication by enriching miRNA-22 within NSC-EVs, which in turn promoted the regeneration and remyelination of axons by targeting the KDM3A/TGF-beta axis and the recovery of neurological outcomes following SCI.

Research progress of exosomes in pathogenesis, diagnosis, and treatment of ocular diseases

Exosomes are natural extracellular vesicles with a diameter of 30-150 nm, which exist in biological fluids and contain biomolecules related to the parent cell, such as proteins, nucleic acids, lipids, etc. It has a wide range of biological functions, and participates in the regulation of important physiological and pathological activities of the body. It can be used as a biomarker for early diagnosis of ocular diseases, a potential therapeutic target, a targeted drug carrier, and has a high potential for clinical application. In this paper, we summarized the genesis mechanism, biological functions, research and application progress of exosomes, focused on the engineering strategy of exosomes, and summarized the advantages and disadvantages of common engineering exosome preparation methods. Systematically combed the role of exosomes in corneal diseases, glaucoma, and retinal diseases, to provide a reference for further understanding of the role of exosomes in the pathogenesis, diagnosis, and treatment of ocular diseases. Finally, we further summarized the opportunities and challenges of exosomes for precision medicine. The extension of exosome research to the field of ophthalmology will help advance current diagnostic and therapeutic methods. Tiny exosomes have huge potential.

Angiogenic ability of human endothelial cells was decreased following senescence induction with hydrogen peroxide: possible role of vegfr-2/akt-1 signaling pathway

Background

Many attempts are used to discover mechanisms driving impaired angiogenesis in age-related diseases. Angiogenesis is highly regulated by different signaling pathways. Here, we investigated the angiogenesis potential of human endothelial cells (ECs) upon exposure to hydrogen peroxide (H2O2), a cellular senescent factor.

Results

Data showed that the wound healing rate of HUVECs decreased upon incubation with H2O2 (P < 0.05). LOX activity and NO production were decreased in H2O2 treated cells (P < 0.05). Expression of miR-126 and VEGFR-2 up-regulated, while expression of miR-373 and HSP-70 up = regulated in H2O2 -induced cells (P < 0.05). In addition, we found that protein levels of p-Akt-1, VCAM-1, MMP-9, and IL-6 decreased in treated cells (P < 0.05).

Conclusions

Our data showed that H2O2 reduced the angiogenic response of HUVECs in vitro, which may be due to impairment of the VEGFR-2 signaling pathway.

Future perspective of stem cell-derived exosomes: Cell-free therapeutic strategies for retinal degeneration

With continued expansion of the aged population, the number of patients with retinal degeneration, which is a leading cause of vision loss worldwide, is growing. Stem cell therapies offer hope for regeneration and repair of damaged retinal tissue. Recent reports have highlighted stem cell-derived paracrine mediators, such as exosomes, which appear to exert a therapeutic benefit similar to their cell of origin and do not carry the risk of cell transplantation. One speculated role is that exosomes likely mediate intercellular communication and material exchange. This review depicts the molecular mechanisms underlying exosome-based therapy, especially in retina degeneration diseases. In the future, the use of stem cell-derived exosomes could be considered a novel and cell-free therapeutic strategy in regenerative medicine.

Update on the application of mesenchymal stem cell-derived exosomes in the treatment of Parkinson's disease: A systematic review

Parkinson's disease (PD) has become the second largest neurodegenerative disease after Alzheimer's disease, and its incidence is increasing year by year. Traditional dopamine replacement therapy and deep brain stimulation can only alleviate the clinical symptoms of patients with PD but cannot cure the disease. In recent years, stem cell therapy has been used to treat neurodegenerative diseases. Many studies have shown that stem cell transplantation has a therapeutic effect on PD. Here, we review recent studies indicating that exosomes derived from mesenchymal stem cells also have the potential to treat PD in animal models, but the exact mechanism remains unclear. This article reviews the mechanisms through which exosomes are involved in intercellular information exchange, promote neuroprotection and freely cross the blood-brain barrier in the treatment of PD. The increase in the incidence of PD and the decline in the quality of life of patients with advanced PD have placed a heavy burden on patients, families and society. Therefore, innovative therapies for PD are urgently needed. Herein, we discuss the mechanisms underlying the effects of exosomes in PD, to provide new insights into the treatment of PD. The main purpose of this article is to explore the therapeutic potential of exosomes derived from mesenchymal stem cells and future research directions for this degenerative disease.

The distinct roles of exosomes in innate immune responses and therapeutic applications in cancer

The innate immune system is one of the major constituents of the host's defense against invading pathogens and extracellular vesicles (EVs) are involved in regulating its responses. Exosomes, a subclass of EVs, released from eukaryotic cells, contribute to intracellular communication and drive various biological processes by transferring nuclei acids, proteins, lipids, and carbohydrates between cells, protecting cargo from enzymatic degradation and immune recognition and consequent elimination by the immune system. A growing body of evidence has revealed that exosomes produced from host cells, infected cells, tumor cells, and immune cells regulate innate immune signaling and responses and thus play a significant role in the propagation of pathogens. Immune cells can recognize exosomes-bearing components including DNA strands, viral RNAs, and even proteins by various mechanisms such as through Toll-like receptor/NF-κB signaling, inducing cytokine production and reprogramming the innate immune responses, immunosuppression or immunesupportive. There is persuasive preclinical and clinical evidence that exosomes are therapeutic strategies for immunotherapy, cancer vaccine, drug-delivery system, and diagnostic biomarker. However, further scrutiny is essential to validate these findings. In this review, we describe the current facts on the regulation of innate immune responses by exosomes. We also describe the translational application of exosomes as cancer-therapy agents and immunotherapy.

A review on exosomes application in clinical trials: perspective, questions, and challenges

BACKGROUND

Exosomes are progressively known as significant mediators of cell-to-cell communication. They convey active biomolecules to target cells and have vital functions in several physiological and pathological processes, and show substantial promise as novel treatment strategies for diseases.

METHODS

In this review study, we studied numerous articles over the past two decades published on application of exosomes in different diseases as well as on perspective and challenges in this field.

RESULTS

The main clinical application of exosomes are using them as a biomarker, cell-free therapeutic agents, drug delivery carriers, basic analysis for exosome kinetics, and cancer vaccine. Different exosomes from human or plant sources are utilized in various clinical trials. Most researchers used exosomes from the circulatory system for biomarker experiments. Mesenchymal stem cells (MSCs) and dendritic cells (DCs) are two widely held cell sources for exosome use. MSCs-derived exosomes are commonly used for inflammation treatment and drug delivery, while DCs-exosomes are used to induce inflammation response in cancer patients. However, the clinical application of exosomes faces various questions and challenges. In addition, translation of exosome-based clinical trials is required to conform to specific good manufacturing practices (GMP). In this review, we summarize exosomes in the clinical trials according to the type of application and disease. We also address the main questions and challenges regarding exosome kinetics and clinical applications.

CONCLUSIONS

Exosomes are promising platforms for treatment of many diseases in clinical trials. This exciting field is developing hastily, understanding of the underlying mechanisms that direct the various observed roles of exosomes remains far from complete and needs further multidisciplinary research in working with these small vesicles. Video Abstract.

Engineered extracellular vesicles: A novel platform for cancer combination therapy and cancer immunotherapy

Extracellular vesicles (EVs), phospholipid membrane-bound vesicles, produced by most cells, contribute to cell-cell communication. They transfer several proteins, lipids, and nucleic acids between cells both locally and systemically. Owing to the biocompatibility and immune activity of EVs, therapeutic approaches using these vesicles as drug delivery systems are being developed. Different methods are used to design more effective engineered EVs, which can serve as smart tools in cancer therapy and immunotherapy. Recent progress in the field of targeted-cancer therapy has led to the gradual use of engineered EVs in combinational therapy to combat heterogeneous tumor cells and multifaceted tumor microenvironments. The high plasticity, loading ability, and genetic manipulation capability of engineered EVs have made them the ideal platforms to realize numerous combinations of cancer therapy approaches. From the combination therapy view, engineered EVs can co-deliver chemotherapy with various therapeutic agents to target tumor cells effectively, further taking part in immunotherapy-related cancer combination therapy. However, a greater number of studies were done in pre-clinical platforms and the clinical translation of these studies needs further scrutiny because some challenges are associated with the application of engineered EVs. Given the many therapeutic potentials of engineered EVs, this review discusses their function in various cancer combination therapy and immunotherapy-related cancer combination therapy. In addition, this review describes the opportunities and challenges associated with the clinical application of engineered EVs.

Emerging innovations on exosome-based onco-therapeutics

Exosomes, nano-sized extracellular vesicles for intercellular communications, are gaining rapid momentum as a novel strategy for the diagnosis and therapeutics of a spectrum of diseases including cancers. Secreted by various cell sources, exosomes pertain numerous functionalities from their parental cells and have enhanced stability that enable them with many features favorable for clinical use and commercialization. This paper focuses on the possible roles of exosomes in cancer therapeutics and reviews current exosome-based innovations toward enhanced cancer management and challenges that limit their clinical translation. Importantly, this paper casts insights on how cold atmospheric plasma, an emerging anticancer strategy, may aid in innovations on exosome-based onco-therapeutics toward improved control over cancers.

Exosomes in pathogenesis, diagnosis, and treatment of pulmonary fibrosis

Pulmonary fibrosis (PF) is a group of interstitial lung diseases that seriously endanger human life and health. Despite the current advances in research on the pathogenesis and treatment of PF, the overall quality of survival and survival rates of PF patients remain low, prompting the search for more effective therapeutic approaches. Exosomes are nanoscale vesicles with diameters ranging from approximately 30–150 nm, capable of transporting a variety of molecules in the body and mediating intercellular communication. There is an increasing number of studies focusing on the role of exosomes in PF. This review demonstrates the significance of exosomes in the pathogenesis, diagnosis, and treatment of PF. Exosomes are able to influence inflammatory, immune, and extracellular matrix deposition processes in PF and regulate the corresponding cytokines. Some exosomes detected in sputum, blood, and bronchoalveolar lavage fluid may be used as potential diagnostic and prognostic biomarkers for PF. Exosomes derived from several cells, such as mesenchymal stem cells, have demonstrated potential as PF therapeutic agents. Drug delivery systems using exosomes may also provide new insights into PF therapy.

Research progress of exosomes in orthopedics

Exosomes are nano-extracellular vesicles secreted by a variety of cells. They are composed of a double-layer membrane that can transport a variety of proteins, coding and non-coding genes, and bioactive substances. Exosomes participate in information transmission between cells and regulate processes such as cell proliferation, migration, angiogenesis, and phenotypic transformation. They have broad prospects in the occurrence, development, and treatment of many diseases including orthopedics. Exosomes derived from different types of bone cells such as mesenchymal stem cells, osteoblasts, osteoclasts, and their precursors are recognized to play pivotal roles in bone remodeling processes including osteogenesis, osteoclastogenesis, and angiogenesis. This articlesummarizes the characteristics of exosomes and their research progress in bone remodeling, bone tumors, vascular skeletal muscle injury, spinal cord injury, degenerative disc diseases, cartilage degeneration, osteoarthritis, necrosis of the femoral head, and osteoporosis.

Nano-Messengers of the Heart: Promising Theranostic Candidates for Cardiovascular Maladies

Till date, cardiovascular diseases remain a leading cause of morbidity and mortality across the globe. Several commonly used treatment methods are unable to offer safety from future complications and longevity to the patients. Therefore, better and more effective treatment measures are needed. A potential cutting-edge technology comprises stem cell-derived exosomes. These nanobodies secreted by cells are intended to transfer molecular cargo to other cells for the establishment of intercellular communication and homeostasis. They carry DNA, RNA, lipids, and proteins; many of these molecules are of diagnostic and therapeutic potential. Several stem cell exosomal derivatives have been found to mimic the cardioprotective attributes of their parent stem cells, thus holding the potential to act analogous to stem cell therapies. Their translational value remains high as they have minimal immunogenicity, toxicity, and teratogenicity. The current review highlights the potential of various stem cell exosomes in cardiac repair, emphasizing the recent advancements made in the development of cell-free therapeutics, particularly as biomarkers and as carriers of therapeutic molecules. With the use of genetic engineering and biomimetics, the field of exosome research for heart treatment is expected to solve various theranostic requirements in the field paving its way to the clinics.

Mesenchymal stem cells derived extracellular vesicles: A promising nanomedicine for drug delivery system

An ideal drug delivery system should selectively deliver incorporated therapeutics to the target site, escape from immune cells recognition and degradation, and act controlled release of incorporated therapeutics in the site targeted. Extracellular vesicles (EVs) have gained great attention for their potential application as a drug delivery system in nanomedicine. EVs such as exosomes are membrane-bound vesicles that contribute to intracellular communication by transferring various biomolecules including RNAs, proteins, and lipids. EVs derived from mesenchymal stem cells (MSCs-EVs) have several advantages such as low immunogenicity, high biocompatibility, and stability against conventional synthetic carriers, opening new avenues for delivering theaputic agents to target cells. To obtain modified MSCs-EVs, several loading methods are used to incorporate different therapeutic agents including proteins, RNAs, and chemotherapeutic drugs into MSCs-EVs. In addition, modification of MSCs-EVs surface may improve their potential in targeted therapies. Modified MSCs-EVs have been shown to improve many diseases including, cancer, cardiovascular diseases, and diabetes mellitus. While land greatly potential, the application of MSCs-EVs as a drug-delivery system has been hampered by several challenges. Clinical translation of modified-EVs needs further scrutiny. In this review, we discuss the biogenesis and production of EVs along with the loading and modification methods of MSCs-EVs. We also describe numerous MSCs-EVs based delivery studies with a focus on advantages and challenges when using them as a drug delivery system.

Unconventional Protein Secretion Dependent on Two Extracellular Vesicles: Exosomes and Ectosomes

In addition to conventional protein secretion, dependent on the specific cleavage of signal sequences, proteins are secreted by other processes, all together called unconventional. Among the mechanisms operative in unconventional secretion, some are based on two families of extracellular vesicle (EVs), expressed by all types of cells: the exosomes (before secretion called ILVs) and ectosomes (average diameters ∼70 and ∼250 nm). The two types of EVs have been largely characterized by extensive studies. ILVs are assembled within endocytic vacuoles by inward budding of small membrane microdomains associated to cytosolic cargos including unconventional secretory proteins. The vacuoles containing ILVs are called multivesicular bodies (MVBs). Upon their possible molecular exchange with autophagosomes, MVBs undergo two alternative forms of fusion: 1. with lysosomes, followed by large digestion of their cargo molecules; and 2. with plasma membrane (called exocytosis), followed by extracellular diffusion of exosomes. The vesicles of the other type, the ectosomes, are differently assembled. Distinct plasma membrane rafts undergo rapid outward budding accompanied by accumulation of cytosolic/secretory cargo molecules, up to their sewing and pinching off. Both types of EV, released to the extracellular fluid in their complete forms including both membrane and cargo, start navigation for various times and distances, until their fusion with target cells. Release/navigation/fusion of EVs establish continuous tridimensional networks exchanging molecules, signals and information among cells. The proteins unconventionally secreted via EVs are a few hundreds. Some of them are functionally relevant (examples FADD, TNF, TACE), governing physiological processes and important diseases. Such proteins, at present intensely investigated, predict future discoveries and innovative developments, relevant for basic research and clinical practice.

Disagreements in the therapeutic use of mesenchymal stem cell-derived secretome

In a recent article, the authors provide a detailed summary of the characteristics and biological functions of mesenchymal stem cells (MSCs), as well as a discussion on the potential mechanisms of action of MSC-based therapies. They describe the morphology, biogenesis, and current isolation techniques of exosomes, one of the most important fractions of the MSC-derived secretome. They also summarize the characteristics of MSC-derived exosomes and highlight their functions and therapeutic potential for tissue/organ regeneration and for kidney, liver, cardiovascular, neurological, and musculoskeletal diseases, as well as cutaneous wound healing. Despite the fact that MSCs are regarded as an important pillar of regenerative medicine, their regenerative potential has been demonstrated to be limited in a number of pathological conditions. The negative effects of MSC-based cell therapy have heightened interest in the therapeutic use of MSC-derived secretome. On the other hand, MSC-derived exosomes and microvesicles possess the potential to have a significant impact on disease development, including cancer. MSCs can interact with tumor cells and promote mutual exchange and induction of cellular markers by exchanging secretome. Furthermore, enzymes secreted into and activated within exosomes can result in tumor cells acquiring new properties. As a result, therapeutic applications of MSC-derived secretomes must be approached with extreme caution.

Exosomes from human induced pluripotent stem cells-derived keratinocytes accelerate burn wound healing through miR-762 mediated promotion of keratinocytes and endothelial cells migration

Background

The use of keratinocytes derived from induced pluripotent stem cells (iPSCs-KCs) may represent a novel cell therapy strategy for burn treatment. There is growing evidence that extracellular vesicles, including exosomes, are primary mediators of the benefits of stem cell therapy. Herein, we thus explored the effects of exosomes produced by iPSCs-derived keratinocytes (iPSCs-KCs-Exos) in a model of deep second-degree burn wound healing and evaluated the mechanistic basis for the observed activity.

Methods

iPSCs-KCs-Exos were isolated from conditioned medium of iPSCs-KCs and verified by electron micrograph and size distribution. Next, iPSCs-KCs-Exos were injected subcutaneously around wound sites, and its efficacy was evaluated by measuring wound closure areas, histological examination, and immunohistochemistry staining. The effects of iPSCs-KCs-Exos on proliferation and migration of keratinocytes and endothelial cells in vitro were assessed by EdU staining, wound healing assays, and transwell assay. Then, high-throughput microRNA sequencing was used to explore the underlying mechanisms. We assessed the roles of miR-762 in iPSCs-KCs-Exos-induced regulation of keratinocytes and endothelial cells migration. Furthermore, the target gene which mediated the biological effects of miR-762 in keratinocytes and endothelial cells was also been detected.

Results

The analysis revealed that iPSCs-KCs-Exos application to the burn wound drove the acceleration of wound closure, with more robust angiogenesis and re-epithelialization being evident. Such iPSCs-KCs-Exos treatment effectively enhanced endothelial cell and keratinocyte migration in vitro. Moreover, the enrichment of miR-762 was detected in iPSCs-KCs-Exos and was found to target promyelocytic leukemia (PML) as a means of regulating cell migration through a mechanism tie to integrin beta1 (ITGB1).

Conclusion

These results thus provide a foundation for the further study of iPSCs-KCs-Exos as novel cell-free treatments for deep second-degree burns.

Graphical Abstract

Recent Advances on the Function and Purification of Milk Exosomes: A Review

Exosomes are nano-scale extracellular vesicles, which can be used as drug carriers, tumor treatment, intestinal development and immune regulator. That is why it has great potential in pharmacy, functional foods, nutritional supplements, especially those for infants, postoperative patients, chemotherapy patients and the elderly. In addition, abnormal exosome level is also related to diseases such as cardiovascular diseases, tumor, diabetes, neurodegenerative and autoimmune diseases, as well as infectious diseases. Despite its high biological significance, pharmaceutical and nutritional value, the low abundancy of exosomes in milk is one of the bottlenecks restricting its in-depth research and real-life application. At present, there is no unified standard for the extraction of breast milk exosomes. Therefore, choosing the proper extraction method is very critical for its subsequent research and development. Based on this, this paper reviewed the purification techniques, the function and the possible applications of milk exosomes based on 47 latest references. Humble advices on future directions, prospects on new ideas and methods which are useful for the study of exosomes are proposed at the end of the paper as well.

Exosomal long noncoding RNAs - the lead thespian behind the regulation, cause and cure of autophagy-related diseases

Recent advances in exosome biology have revealed significant roles of exosome and their contents in intercellular communication. Among various exosomal content, long non-coding RNAs (lncRNAs), which have a large size (˃ 200 nt) and lack protein coding potential, are known to play key roles in intercellular communication and novel biomarkers of various metabolic disorders. Moreover, long non-coding RNAs are often involved in the regulation of various cellular processes such as autophagy, apoptosis, cell proliferation. On the other hand, autophagy is the central regulating point that controls the various metabolic functions of the body. This process is known to prevent diseases and promote longevity. Therefore, the present review discusses the relationship between diseases and autophagy, and also look into the biological functions of exosome-associated lncRNAs in regulating autophagy. Furthermore, this review will summarize some of the studies that provide novel insights into the pathogenesis of autophagy-related diseases followed by the non-canonical roles played by autophagy and related proteins in the development of exosome biogenesis.

The Role of Exosomes in the Progression and Therapeutic Resistance of Hematological Malignancies

Exosomes are membrane limited structures which derive from cell membranes and cytoplasm. When released into extracellular space, they circulate through the extracellular fluid, including the peripheral blood and tissue fluid. Exosomes surface molecules mediate their targeting to specific recipient cells and deliver their contents to recipient cells by receptor-ligand interaction and/or phagocytosis and/or endocytosis or direct fusion with cell membrane. Exosomes contain many functional molecules, including nucleic acids (DNAs, mRNAs, non-coding RNAs), proteins (transcription factors, enzymes), and lipids which have biological activity. By passing these cargos, exosomes can transfer information between cells. In this way, exosomes are extensively involved in physiological and pathological processes, such as angiogenesis, matrix reprogramming, coagulation, tumor progression. In recent years, researcher have found that exosomes from malignant tumors can mediate information exchange between tumor cells or between tumor cells and non-tumor cells, thereby promoting tumor survival, progression, and resistance to therapy. In this review, we discuss the pro-tumor and anti-therapeutic effects of exosomes in hematological malignancies, hoping to contribute to the early conquest of hematological malignancy.

Plant-derived extracellular vesicles: a novel nanomedicine approach with advantages and challenges

BACKGROUND

Many eukaryote cells produce membrane-enclosed extracellular vesicles (EVs) to establish cell-to-cell communication. Plant-derived EVs (P-EVs) contain proteins, RNAs, lipids, and other metabolites that can be isolated from the juice, the flesh, and roots of many species.

METHODS

In the present review study, we studied numerous articles over the past two decades published on the role of P-EVs in plant physiology as well as on the application of these vesicles in different diseases.

RESULTS

Different types of EVs have been identified in plants that have multiple functions including reorganization of cell structure, development, facilitating crosstalk between plants and fungi, plant immunity, defense against pathogens. Purified from several edible species, these EVs are more biocompatible, biodegradable, and extremely available from many plants, making them useful for cell-free therapy. Emerging evidence of clinical and preclinical studies suggest that P-EVs have numerous benefits over conventional synthetic carriers, opening novel frontiers for the novel drug-delivery system. Exciting new opportunities, including designing drug-loaded P-EVs to improve the drug-delivery systems, are already being examined, however clinical translation of P-EVs-based therapies faces challenges.

CONCLUSION

P-EVs hold great promise for clinical application in the treatment of different diseases. In addition, despite enthusiastic results, further scrutiny should focus on unravelling the detailed mechanism behind P-EVs biogenesis and trafficking as well as their therapeutic applications. Video Abstract.

CD73-Positive Small Extracellular Vesicles Derived From Umbilical Cord Mesenchymal Stem Cells Promote the Proliferation and Migration of Pediatric Urethral Smooth Muscle Cells Through Adenosine Pathway

Smooth muscle cells (SMCs) are the main functional component of urethral tissue, but are difficult to proliferate in vitro. Mesenchymal stem cells (MSCs) and mesenchymal stem cell-derived small extracellular vesicles (MSC-sEV) have been shown to promote tissue repair by regulating the proliferation and migration of different types of cells. In this study, we investigated the effect of umbilical cord mesenchymal stem cell-derived sEV (UCMSC-sEV) on the proliferation and migration of pediatric urethral smooth muscle cells (PUSMCs) and the mechanism by which sEV regulates the function of PUSMCs. We observed that UCMSC-sEV can significantly promote the proliferation and migration of PUSMCs in vitro. UCMSC-sEV exerted proliferation and migration promotion effects by carrying the CD73 to PUSMCs and catalyzing the production of adenosine. Conversely, the effect of UCMSC-sEV on the proliferation and migration of PUSMCs were no longer observed with addition of the PSB12379 as a CD73 inhibitor. It was found that the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway in PUSMCs was activated by adenosine or UCMSC-sEV intervention. In summary, UCMSC-sEV promoted proliferation and migration of PUSMCs in vitro by activating CD73/adenosine signaling axis and downstream PI3K/AKT pathway. Thus, we concluded that UCMSC-sEV may be suggested as a new solution strategy for the urethral tissue repair.

Exosomes Derived From Mesenchymal Stem Cells: Novel Effects in the Treatment of Ischemic Stroke

Ischemic stroke is defined as an infarction in the brain, caused by impaired cerebral blood supply, leading to local brain tissue ischemia, hypoxic necrosis, and corresponding neurological deficits. At present, revascularization strategies in patients with acute ischemic stroke include intravenous thrombolysis and mechanical endovascular treatment. However, due to the short treatment time window (<4.5 h) and method restrictions, clinical research is focused on new methods to treat ischemic stroke. Exosomes are nano-sized biovesicles produced in the endosomal compartment of most eukaryotic cells, containing DNA, complex RNA, and protein (30-150 nm). They are released into surrounding extracellular fluid upon fusion between multivesicular bodies and the plasma membrane. Exosomes have the characteristics of low immunogenicity, good innate stability, high transmission efficiency, and the ability to cross the blood-brain barrier, making them potential therapeutic modalities for the treatment of ischemic stroke. The seed sequence of miRNA secreted by exosomes is base-paired with complementary mRNA to improve the microenvironment of ischemic tissue, thereby regulating downstream signal transduction activities. With exosome research still in the theoretical and experimental stages, this review aims to shed light on the potential of exosomes derived from mesenchymal stem cells in the treatment of ischemic stroke.

Exosomal miR-106a-5p accelerates the progression of nasopharyngeal carcinoma through FBXW7-mediated TRIM24 degradation

Nasopharyngeal carcinoma (NPC) is prevalent in East Asia and causes increased health burden. Elucidating the regulatory mechanism of NPC progression is important for understanding the pathogenesis of NPC and developing novel therapeutic strategies. Nasopharyngeal carcinoma and normal tissues were collected. Nasopharyngeal carcinoma cell proliferation, migration, and invasion were evaluated using CCK-8, colony formation, wound healing, and transwell assays, respectively. A xenograft mouse model of NPC was established to analyze NPC cell growth and metastasis in vivo. The expression of miR-106a-5p, FBXW7, TRIM24, and SRGN was determined with RT-qPCR and Western blot. MiR-106a-5p, TRIM24, and SRGN were upregulated, and FBXW7 was downregulated in NPC tissues and cells. Exosomal miR-106a-5p could enter NPC cells, and its overexpression promoted the proliferation, migration, invasion, and metastasis of NPC cells, which were suppressed by knockdown of exosomal miR-106a-5p. MiR-106a-5p targeted FBXW7 to regulate FBXW7-mediated degradation of TRIM24. Furthermore, TRIM24 regulated SRGN expression by binding to its promoter in NPC cells. Suppression of exosomal miR-106a-5p attenuated NPC growth and metastasis through the FBXW7-TRIM24-SRGN axis in vivo. Exosomal miR-106a-5p accelerated the progression of NPC through the FBXW7-TRIM24-SRGN axis. Our study elucidates novel regulatory mechanisms of NPC progression and provides potential exosome-based therapeutic strategies for NPC.

Platelet-Derived Exosomes and Atherothrombosis

Platelet-derived exosomes (PLT-Exos) are the main subtype of extracellular vesicles secreted by platelets, which carry proteins, nucleotides, lipids, and other substances to acceptor cells, playing an important role in intercellular communication. PLT-Exos increase with platelet activation and are involved in the process of atherothrombosis by delivering cargo to acceptor cells. Atherosclerotic plaque rupture, causing thrombosis and arterial occlusion, is the basic pathological change leading to cardiovascular events. PLT-Exos from different donors have different functions. PLT-Exos secreted by healthy volunteer or mice can inhibit platelet activation and inflammation of endothelial cells, thus exerting an antithrombotic effect, while PLT-Exos derived from some patients induce endothelial apoptosis and an inflammatory response to promote atherothrombosis. Furthermore, increased PLT-Exos reflect platelet activation and their cargoes also are derived from platelets; therefore, PLT-Exos can also be used as a biomarkers for the diagnosis and prognosis of cardiovascular disease. This article reviews the characteristics of PLT-Exos and discusses their role in cell-to-cell communication and atherothrombosis.

Autophagy and Exosome Coordinately Enhance Macrophage M1 Polarization and Recruitment in Influenza A Virus Infection

Background

Influenza A virus infection results in viral pneumonia, which is often accompanied by the infiltration and recruitment of macrophages, overactivation of inflammatory responses, and obvious cell autophagy and exosome production. However, little is known about the roles of autophagy and exosome production in these inflammatory responses.

Methods

In this study, multiple methods, such as flow cytometry, real-time quantitative reverse transcription-polymerase chain reaction, immune–fluorescence technology, and western blot, were applied to explore the possible effects of autophagy and exosome production by H1N1-infected host cells.

Results

It was observed that a high number of polarized macrophages (CD11b⁺/F4/80⁺/CD86⁺) were recruited to the lung tissues of infected mice, which could be mimicked by tracking the movement of macrophages to H1N1-infected cells in vitro (transwell assays). Furthermore, there was some coordinated upregulation of M1 polarization signs (iNOS/Arg-1 bias) as well as autophagy (LC3) and exosome (CD63) biomarkers in the infected macrophages and epithelial cells. Moreover, exosomes extracted from the supernatant of virus-infected cells were shown to promote the recruitment and polarization of more peritoneal macrophages than the normal group. The fluorescence colocalization of LC3-CD63 and the inhibition of autophagy and exosome signaling pathway further revealed that H1N1 infection seemed to sequentially activate the M1 polarization and recruitment of macrophages via autophagy–exosome dependent pathway.

Conclusion

Autophagy and exosome production coordinately enhance the M1 polarization and recruitment of macrophages in influenza virus infection, which also provides potential therapeutic targets.

Cellular Chitchatting: Exploring the Role of Exosomes as Cardiovascular Risk Factors

Exosomes are small bi-lipid membranous vesicles (30–150 nm) containing different biological material such as proteins, lipids and nucleic acid. These small vesicles, inducing a cell to cell signaling pathway, are able to mediate multidirectional crosstalk to maintain homeostasis or modulate disease processes. With their various contents, exosomes sort and transfer specific information from their origin to a recipient cell, from a tissue or organ in the close proximity or at distance, generating an intra-inter tissue or organ communication. In the last decade exosomes have been identified in multiple organs and fluids under different pathological conditions. In particular, while the content and the abundance of exosome is now a diagnostic marker for cardiovascular diseases, their role in context-specific physiological and pathophysiological conditions in the cardiovascular system remains largely unknown. We summarize here the current knowledge on the role of exosomes as mediators of cardiovascular diseases in several pathophysiological conditions such as atherosclerosis and diabetes. In addition, we describe evidence of intercellular connection among multiple cell type (cardiac, vasculature, immune cells) as well as the challenge of their in vivo analysis.

Exosomes as Promising Nanostructures in Diabetes Mellitus: From Insulin Sensitivity to Ameliorating Diabetic Complications

Diabetes mellitus (DM) is among the chronic metabolic disorders that its incidence rate has shown an increase in developed and wealthy countries due to lifestyle and obesity. The treatment of DM has always been of interest, and significant effort has been made in this field. Exosomes belong to extracellular vesicles with nanosized features (30-150 nm) that are involved in cell-to-cell communication and preserving homeostasis. The function of exosomes is different based on their cargo, and they may contain lipids, proteins, and nucleic acids. The present review focuses on the application of exosomes in the treatment of DM; both glucose and lipid levels are significantly affected by exosomes, and these nanostructures enhance lipid metabolism and decrease its deposition. Furthermore, exosomes promote glucose metabolism and affect the level of glycolytic enzymes and glucose transporters in DM. Type I DM results from the destruction of β cells in the pancreas, and exosomes can be employed to ameliorate apoptosis and endoplasmic reticulum (ER) stress in these cells. The exosomes have dual functions in mediating insulin resistance/sensitivity, and M1 macrophage-derived exosomes inhibit insulin secretion. The exosomes may contain miRNAs, and by transferring among cells, they can regulate various molecular pathways such as AMPK, PI3K/Akt, and β-catenin to affect DM progression. Noteworthy, exosomes are present in different body fluids such as blood circulation, and they can be employed as biomarkers for the diagnosis of diabetic patients. Future studies should focus on engineering exosomes derived from sources such as mesenchymal stem cells to treat DM as a novel strategy.

Inhibition of extracellular vesicle biogenesis in tumor cells: A possible way to reduce tumorigenesis

Most eukaryotic cells secrete extracellular vesicles (EVs), which contribute to intracellular communication through transferring different biomolecules such as proteins, RNAs, and lipids to cells. Two main types of EVs are exosomes and microvesicles. Exosomes originate from multivesicular bodies, while microvesicles are shed from the plasma membrane. Mechanisms of exosomes and microvesicle biogenesis/trafficking are complex and many molecules are involved in their biogenesis and secretion. Tumor-derived EVs contain oncogenic molecules that promote tumor growth, metastasis, immune surveillance, angiogenesis, and chemoresistance. A growing body of evidence indicates various compounds can inhibit biogenesis and secretion of EVs from cells and several experiments were conducted to use EVs-inhibitors for understanding the biology of the cells or for understanding the pathology of several diseases like cancer. However, the nontargeting effects of drugs/inhibitors remain a concern. Our current knowledge of EVs biogenesis and their inhibition from tumor cells may provide an avenue for cancer management. In this review, we shed light on exosomes and microvesicles biogenesis, key roles of tumor-derived EVs, and discuss methods used to inhibition of EVs by different inhibitors.

Tumor-derived extracellular vesicles: The metastatic organotropism drivers

The continuous growing, spreading, and metastasis of tumor cells depend on intercellular communication within cells resident in a tissue environment. Such communication is mediated through the secretion of particles from tumor cells and resident cells known as extracellular vesicles (EVs) within a microenvironment. EVs are a heterogeneous population of membranous vesicles released from tumor cells that transfer many types of active biomolecules to recipient cells and induce physiologic and phenotypic alterations in the tissue environment. Spreading the 'seeds' of metastasis needs the EVs that qualify the 'soil' at distant sites to promote the progress of arriving tumor cells. Growing evidence indicates that EVs have vital roles in tumorigenesis, including pre-metastatic niche formation and organotropic metastasis. These EVs mediate organotropic metastasis by modifying the pre-metastatic microenvironment through different pathways including induction of phenotypic alternation and differentiation of cells, enrolment of distinct supportive stromal cells, up-regulation of the expression of pro-inflammatory genes, and induction of immunosuppressive status. However, instead of pre-metastatic niche formation, evidence suggests that EVs may mediate reawakening of dormant niches. Findings regarding EVs function in tumor metastasis have led to growing interests in the interdisciplinary significance of EVs, including targeted therapy, cell-free therapy, drug-delivery system, and diagnostic biomarker. In this review, we discuss EVs-mediated pre-metastatic niche formation and organotropic metastasis in visceral such as lung, liver, brain, lymph node, and bone with a focus on associated signaling, causing visceral environment hospitable for metastatic cells. Furthermore, we present an overview of the possible therapeutic application of EVs in cancer management.

The interplay of autophagy and oxidative stress in the pathogenesis and therapy of retinal degenerative diseases

Oxidative stress is mainly caused by intracellular reactive oxygen species (ROS) production, which is highly associated with normal physiological homeostasis and the pathogenesis of diseases, particularly ocular diseases. Autophagy is a self-clearance pathway that removes oxidized cellular components and regulates cellular ROS levels. ROS can modulate autophagy activity through transcriptional and posttranslational mechanisms. Autophagy further triggers transcription factor activation and degrades impaired organelles and proteins to eliminate excessive ROS in cells. Thus, autophagy may play an antioxidant role in protecting ocular cells from oxidative stress. Nevertheless, excessive autophagy may cause autophagic cell death. In this review, we summarize the mechanisms of interaction between ROS and autophagy and their roles in the pathogenesis of several ocular diseases, including glaucoma, age-related macular degeneration (AMD), diabetic retinopathy (DR), and optic nerve atrophy, which are major causes of blindness. The autophagy modulators used to treat ocular diseases are further discussed. The findings of the studies reviewed here might shed light on the development and use of autophagy modulators for the future treatment of ocular diseases.

A systematic review and Meta-analysis of urinary extracellular vesicles proteome in diabetic nephropathy

Diabetic nephropathy (DN) is a major microvascular complication of both type 1 and type 2 diabetes mellitus and is the most frequent cause of end-stage renal disease with an increasing prevalence. Presently there is no non-invasive method for differential diagnosis, and an efficient target therapy is lacking. Extracellular vesicles (EV), including exosomes, microvesicles, and apoptotic bodies, are present in various body fluids such as blood, cerebrospinal fluid, and urine. Proteins in EV are speculated to be involved in various processes of disease and reflect the original cells' physiological states and pathological conditions. This systematic review is based on urinary extracellular vesicles studies, which enrolled patients with DN and investigated the proteins in urinary EV. We systematically reviewed articles from the PubMed, Embase, Web of Science databases, and China National Knowledge Infrastructure (CNKI) database until January 4, 2022. The article quality was appraised according to the Newcastle-Ottawa Quality Assessment Scale (NOS). The methodology of samples, isolation and purification techniques of urinary EV, and characterization methods are summarized. Molecular functions, biological processes, and pathways were enriched in all retrievable urinary EV proteins. Protein-protein interaction analysis (PPI) revealed pathways of potential biomarkers. A total of 539 articles were retrieved, and 13 eligible records were enrolled in this systematic review and meta-analysis. And two studies performed mass spectrometry to obtain the proteome profile. Two of them enrolled only T1DM patients, two studies enrolled both patients with T1DM and T2DM, and other the nine studies focused on T2DM patients. In total 988 participants were enrolled, and DN was diagnosed according to UACR, UAER, or decreased GFR. Totally 579 urinary EV proteins were detected and 28 of them showed a potential value to be biomarkers. The results of bioinformatics analysis revealed that urinary EV may participate in DN through various pathways such as angiogenesis, biogenesis of EV, renin-angiotensin system, fluid shear stress and atherosclerosis, collagen degradation, and immune system. Besides that, it is necessary to report results compliant with the guideline of ISEV, in orderto assure repeatability and help for further studies. This systematic review concordance with previous studies and the results of meta-analysis may help to value the methodology details when urinary EV proteins were reported, and also help to deepen the understanding of urinary EV proteins in DN.

Exosomes: Emerging implementation of nanotechnology for detecting and managing novel corona virus- SARS-CoV-2

The spread of SARS-CoV-2 as an emerging novel coronavirus disease (COVID-19) had progressed as a worldwide pandemic since the end of 2019. COVID-19 affects firstly lungs tissues which are known for their very slow regeneration. Afterwards, enormous cytokine stimulation occurs in the infected cells immediately after a lung infection which necessitates good management to save patients. Exosomes are extracellular vesicles of nanometric size released by reticulocytes on maturation and are known to mediate intercellular communications. The exosomal cargo serves as biomarkers in diagnosing various diseases; moreover, exosomes could be employed as nanocarriers in drug delivery systems. Exosomes look promising to combat the current pandemic since they contribute to the immune response against several viral pathogens. Many studies have proved the potential of using exosomes either as viral elements or host systems that acquire immune-stimulatory effects and could be used as a vaccine or drug delivery tool. It is essential to stop viral replication, prevent and reverse the massive storm of cytokine that worsens the infected patients' situations for the management of COVID-19. The main benefits of exosomes could be; no cells will be introduced, no chance of mutation, lack of immunogenicity and the damaged genetic material that could negatively affect the recipient is avoided. Additionally, it was found that exosomes are static with no ability for in vivo reproduction. The current review article discusses the possibilities of using exosomes for detecting novel coronavirus and summarizes state of the art concerning the clinical trials initiated for examining the use of COVID-19 specific T cells derived exosomes and mesenchymal stem cells derived exosomes in managing COVID-19.

Extracellular vesicle-derived miR-320a targets ZC3H12B to inhibit tumorigenesis, invasion, and angiogenesis in ovarian cancer

Extracellular vesicles (EVs) play crucial roles in intercellular communication. miRNAs derived from EVs emerge as promising diagnostic indicators and therapeutic targets in a variety of malignancies. Tremendous studies have revealed the function of miRNAs derived from EVs in tumorigenesis, metastasis and other aspects. The mechanism of action of EV-derived miRNAs, however, in ovarian cancer remains largely unknown. In this study, EVs were enriched from the ovarian cancer cell lines. EVs as a whole could promote cell proliferation, invasion and new vasculature formation. However, the down-regulated EV-derived miR-320a was demonstrated to potentially suppress tumorigenesis, metastasis and angiogenesis. Moreover, EV-derived miR-320a has been proved to directly regulate a previously unknown target, ZC3H12B. An unreported role of ZC3H12B in promoting ovarian cancer cell proliferation has been elucidated and miR-320a could mediate the expression of ZC3H12B, thereby inhibiting the downstream response. As for the practical clinic values, lower expression of EV-derived miR-320a correlates with shorter survival period, indicating that EV-derived miR-320a may also serve as a prognostic biomarker in ovarian cancer. This research provides new insight into the molecular mechanism of EV-derived miR-320a in ovarian cancer and may provide new therapeutic and prognostic strategies for ovarian cancer treatment.