Decreased amyloid-β pathologies by intracerebral loading of glycosphingolipid-enriched exosomes in Alzheimer model mice

Bioinspired nanomedicines for the management of osteosarcoma: Recent progress and perspectives

Osteosarcoma (OS) is the most prevalent malignant primary bone tumor, predominantly affecting children and young adults between the ages of 11 and 20. OS presents huge challenges in treatment because of its aggressive nature and high metastatic potential. Chemotherapeutic drugs have attracted considerable interest for the treatment of OS, but they suffer from poor targeting, low bioavailability, severe side effects, and the multi-drug resistance acquired by the tumor. Therefore, it is imperative to develop novel therapeutic tactics that can improve OS outcomes while minimizing toxicity. Bioinspired nanoparticles, designed through exploiting or simulating the biological structures and processes, provide promising strategies for the treatment of OS. In this review, we elaborate on the biological properties and biomedical applications of state-of-the-art bioinspired nanoparticles, including cell membrane-based nanoparticles, exosome-based nanoparticles, protein template-based nanoparticles, and peptide template-based nanoparticles for the management of OS.

Platelet Extracellular Vesicles as Natural Delivery Vehicles for Mitochondrial Dysfunction Therapy?

Mitochondria are vital for energy production, metabolic regulation, and cellular signaling. Their dysfunction is strongly implicated in neurological, cardiovascular, and muscular degenerative diseases, where energy deficits and oxidative stress accelerate disease progression. Platelet extracellular vesicles (PEVs), once called "platelet dust", have emerged as promising agents for mitigating mitochondrial dysfunction. Like other extracellular vesicles (EVs), PEVs carry diverse molecular cargo and surface markers implicated in disease processes and therapeutic efficacy. Notably, they may possibly contain intact or partially functional mitochondrial components, making them tentatively attractive for targeting mitochondrial damage. Although direct research on PEVs-mediated mitochondrial rescue remains limited, current evidence suggests that PEVs can modulate diseases associated with mitochondrial dysfunction and potentially enhance mitochondrial health. This review explores the therapeutic potential of PEVs in neurodegenerative and cardiovascular disorders, highlighting their role in restoring mitochondrial health. By examining recent advancements in PEVs research, we aim to shed light on novel strategies for utilizing PEVs as therapeutic agents. Our goal is to underscore the importance of further fundamental and applied research into PEVs-based interventions, as innovative tools for combating a wide range of diseases linked to mitochondrial dysfunction.

Therapeutic application of extracellular vesicles in human diseases

Extracellular vesicles (EVs) are membrane vesicles released or secreted from almost all cell types. EVs are derived from multivesicular bodies or from the plasma membrane and contain a subset of proteins, lipids, and nucleic acids (e.g., DNA, RNA, and microRNA [miRNA]) derived from the parent cell. EVs play important roles in intercellular communication by efficiently transferring the content between cells both locally and systemically. Given their natural ability to transfer cargo to cells, sometimes in a targeted manner, and their apparent lack of immunogenicity, EVs are being engineered for delivery of therapeutic RNAs, DNAs, miRNAs, viral particles, drugs, and even proteins. In addition, many of the therapeutic effects of stem cell treatments are mediated by stem cell-derived EVs, which are safer and potentially more effective than the parental stem cells. Here we provide an overview of the use of EVs for delivery of different therapeutic nucleic acids, viruses, and drugs, as well as the use of therapeutic stem cell-derived EVs.

Effect of Small Extracellular Vesicles Produced by Mesenchymal Stem Cells on 5xFAD Mice Hippocampal Cultures

Alzheimer's disease (AD) is one of the most common progressive neurodegenerative diseases leading to impairments in memory, orientation, and behavior. However, significant work is still needed to fully understand the progression of such disease and develop novel therapeutic agents for AD prevention and treatment. Small extracellular vesicles (sEVs) have received attention in recent years due to their potential therapeutic effects on AD. The aim of this study was to determine the potential effect of sEVs in an in vitro model of AD. sEVs were isolated from human Wharton's jelly mesenchymal stem cells (MSCs) by asymmetric depth filtration, a method developed recently by us. AD was modeled in vitro using cells obtained from the hippocampi of newborn 5xFAD transgenic mice carrying mutations involved in familial AD. After isolation, sEVs underwent detailed characterization that included scanning electron microscopy, nanoparticle tracking analysis, confocal microscopy, Western blotting, and Luminex assay. When added to 5xFAD hippocampal cells, sEVs were nontoxic, colocalized with neurons and astrocytes, decreased the level of Aβ peptide, and increased the synaptic density. These results support the possibility that sEVs can improve brain cell function during aging, decrease the risk of AD, and potentially be used for AD therapeutics.

Targeting of Extracellular Vesicle-Based Therapeutics to the Brain

Extracellular vesicles (EVs) have been explored as promising vehicles for drug delivery. One of the most valuable features of EVs is their ability to cross physiological barriers, particularly the blood-brain barrier (BBB). This significantly enhances the development of EV-based drug delivery systems for the treatment of CNS disorders. The present review focuses on the factors and techniques that contribute to the successful delivery of EV-based therapeutics to the brain. Here, we discuss the major methods of brain targeting which includes the utilization of different administration routes, capitalizing on the biological origins of EVs, and the modification of EVs through the addition of specific ligands on to the surface of EVs. Finally, we discuss the current challenges in large-scale EV production and drug loading while highlighting future perspectives regarding the application of EV-based therapeutics for brain delivery.

Research progress of extracellular vesicles derived from mesenchymal stem cells in the treatment of neurodegenerative diseases

As the world's population ages, neurodegenerative diseases are becoming more widely acknowledged as serious global health and socioeconomic issues. Although many resources have been devoted to the research of these illnesses, little progress has been made in the creation of novel diagnostic and therapeutic approaches. Extracellular vesicles (EVs) are released by all cell types and contain proteins, microRNAs, mRNAs, and other biologically active molecules. EVs play an important role in intercellular communication as well as in the regulation of neuroinflammation. Determining the mechanisms by which EVs contribute to the pathogenesis of neurodegenerative diseases will aid in the development of new therapeutic approaches and diagnostic tools. Mesenchymal stem cells (MSCs) have been shown in studies to control immunological responses, promote the growth of new brain connections, promote the production of blood vessels, and heal damaged tissues. There is growing evidence that MSCs' ability to treat patients is mostly due to the neurotrophic compounds they secrete through EVs. Since their tiny size allows them to pass through biological barriers and reach injured parts of the central nervous system, MSC-derived extracellular vesicles (MSC-EVs) retain many of the therapeutic qualities of their parent MSCs. This review discusses the role of EVs in neurodegenerative diseases and highlights the potential of MSC-EVs in the treatment of neurodegenerative diseases. The paper also examines the challenges that still need to be overcome and the prospects for using MSC-EVs to treat neurodegenerative illnesses.

Lipid metabolism, remodelling and intercellular transfer in the CNS

Lipid metabolism encompasses the catabolism and anabolism of lipids, and is fundamental for the maintenance of cellular homeostasis, particularly within the lipid-rich CNS. Increasing evidence further underscores the importance of lipid remodelling and transfer within and between glial cells and neurons as key orchestrators of CNS lipid homeostasis. In this Review, we summarize and discuss the complex landscape of processes involved in lipid metabolism, remodelling and intercellular transfer in the CNS. Highlighted are key pathways, including those mediating lipid (and lipid droplet) biogenesis and breakdown, lipid oxidation and phospholipid metabolism, as well as cell-cell lipid transfer mediated via lipoproteins, extracellular vesicles and tunnelling nanotubes. We further explore how the dysregulation of these pathways contributes to the onset and progression of neurodegenerative diseases, and examine the homeostatic and pathogenic impacts of environment, diet and lifestyle on CNS lipid metabolism.

The role of exosomes in diagnosis, pathophysiology, and management of Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disorder associated with impaired cognitive function and memory loss. Currently, available therapeutics can effectively alleviate the symptoms of AD, but there is a lack of treatment to halt the progression of the disease. In recent years, exosomes have gained much attention due to their involvement in various neurological disorders. Exosomes are small extracellular vesicles comprising lipids, proteins, DNA, non-coding RNA, and mRNAs, can carry various therapeutic molecules, and are potential drug delivery vehicles. Exosomes are known as a double-edged sword due to their involvement in both the pathogenesis and management of AD. This review explores the function of exosomes in the pathophysiology, treatment, and diagnosis of AD, also emphasizing their potential as a targeted drug delivery carrier to the brain. This review seeks to provide novel perspectives to understand better the onset, targeted treatment, and diagnosis of AD using exosomes.

The impact of a heat therapy intervention on pain and fibromyalgia symptoms in patients with fibromyalgia: a pilot study

Introduction

FM is characterized by widespread musculoskeletal pain and associated somatic symptoms including fatigue, cognitive difficulties, and problems with sleeping. Multidisciplinary treatment of fibromyalgia including pharmacologic and non-pharmacologic interventions are recommended to improve symptoms and physical functioning. The goal of the present pilot investigation was to evaluate the effects of heat therapy via hot water immersion on clinical and objective pain measures in addition to blood measurements of heat shock proteins (HSPs) and inflammatory markers in patients with FM.

Methods

After screening, informed consent, and enrollment into the study, all subjects underwent a baseline pre-intervention evaluation which included a battery of pain phenotyping questionnaires, quantitative sensory testing, and collection of blood for measurements of HSPs and inflammatory markers. Subjects received heat therapy three times a week for four weeks, where they were immersed in hot water for 45 min. After four weeks, participants completed the same battery of testing done at baseline.

Results

We found that four weeks of heat therapy via hot water immersion in patients with FM showed statistically significant reductions in average and worst pain NRS severity scores when compared to baseline. There was also statistically significant improvement in overall impact of fibromyalgia symptoms, physical function, and sleep-related impairment. Regarding heat shock proteins, there was a statistically significant reduction in HSP90 and induction of HSP40 and HSC70. The number of extracellular vesicles were also statistically significantly increased. There were no statistically significant changes found in depression, anxiety, quantitative sensory testing measures, or pro- or anti-inflammatory markers.

Conclusions

As a whole, these findings suggest that heat therapy via hot water immersion may be an effective non-pharmaceutical intervention for patients with FM and that its analgesic benefits may be related to decreases in HSP 90 and increases in HSP 40 and 72. Further large-scale, well-powered studies are needed to confirm our preliminary clinical and translational results.

Global status and trends of exosomes in neurodegenerative diseases from 2014 to 2023: a bibliometric and visual analysis

Background

Neurodegenerative diseases (NDs) are chronic and progressive conditions that significantly impact global public health. Recent years have highlighted exosomes as key mechanisms involved in these diseases. This study aims to visualize and analyze the structure and content of exosomes in NDs based on past research to identify new research ideas and directions. Through bibliometric analysis, we assess the current state of research on exosomes in the field of NDs worldwide over the past decade, highlighting significant findings, major research areas, and emerging trends.

Methods

Publications on exosomes in NDs research were obtained from the Web of Science Core Collection (WOSCC) database. Eligible literature was analyzed using Bibliometric R, VOSviewer, and Citespace.

Results

Between 2014 and 2023, 2,393 publications on exosomes in NDs were included in the analysis. The number of relevant publications has been increasing yearly, with China leading in international collaboration, followed by the United States. And China has the largest number of academic scholars as leading and corresponding authors in all the countries, known as the great research society and community. Notable institutions contributing to these publications include Nia, the University of San Francisco California, and Capital Medical University, which rank highly in both publication volume and citations. Dimitrios Kapogiannis is a pivotal figure in the author collaboration network, having produced the highest number of publications (Sato et al., 2011) and amassed 3,921 citations. The journal with the most published articles in this field is The International Journal of Molecular Sciences, which has published 131 articles and received 3,347 citations. A recent analysis of keyword clusters indicates that "Exosome-like liposomes," "Independent mechanisms," and "Therapeutic potential" are emerging research hotspots.

Conclusion

This is the first bibliometric study to provide a comprehensive summary of the research trends and developments regarding exosomes in NDs studies. Future research in this area may explore the role of mesenchymal stromal cells, microRNAs (miRNAs), and targeted drug delivery systems to further investigate the underlying mechanisms and develop new therapeutics.

Glycosylation on extracellular vesicles and its detection strategy: Paving the way for clinical use

Extracellular vesicles (EVs) contain various glycans during their life cycle, from biogenesis to cellular recognition and uptake by recipient cells. EV glycosylation has substantial diagnostic significance in multiple health conditions, highlighting the necessity of determining an accurate glycosylation pattern for EVs from diverse biological fluids. Reliable and accessible glycan detection techniques help to elaborate the glycosylation-related functional alterations of specific proteins or lipids. However, multiple obstacles exist, including the inconsistency in glycosylation patterns between an entire batch of EVs and a specific EV protein, and difficulty in distinguishing glycosylation types after tedious separation and purification procedures. This review outlines recent advances in EV glycan detection, either at the glycomic level for a collection of intact EVs or at the molecular level for a specific protein on EVs. Particular emphasis has been placed on the abundance of EVs in body fluids and their unique characteristics for drug delivery of EVs, indicating an opportunity for diagnostic and therapeutic purposes via EV glycans.

Leveraging nature's nanocarriers: Translating insights from extracellular vesicles to biomimetic synthetic vesicles for biomedical applications

Naturally occurring extracellular vesicles (EVs) and synthetic nanoparticles like liposomes have revolutionized precision diagnostics and medicine. EVs excel in biocompatibility and cell targeting, while liposomes offer enhanced drug loading capacity and scalability. The clinical translation of EVs is hindered by challenges including low yield and heterogeneity, whereas liposomes face rapid immune clearance and limited targeting efficiency. To bridge these gaps, biomimetic synthetic vesicles (SVs) have emerged as innovative platforms, combining the advantageous properties of EVs and liposomes. This review emphasizes critical aspects of EV biology, such as mechanisms of EV-cell interaction and source-dependent functionalities in targeting, immune modulation, and tissue regeneration, informing biomimetic SV engineering. We reviewed a broad array of biomimetic SVs, with a focus on lipid bilayered vesicles functionalized with proteins. These include cell-derived nanovesicles, protein-functionalized liposomes, and hybrid vesicles. By addressing current challenges and highlighting opportunities, this review aims to advance biomimetic SVs for transformative biomedical applications.

Identification of lncRNA in circulating exosomes as potential biomarkers for MCI among the elderly

BACKGROUND

The abnormal expression of lncRNA in elderly patients with mild cognitive impairment (MCI), and the ability of exosomes to stably carry non-coding RNAs provide a reliable physiological basis for exosomal lncRNA in plasma as a biomarker of MCI.

METHODS

This case-control study enrolled 155 patients with MCI and 155 healthy controls from a community-based population aged≥60 years. The expression profiles of lncRNA and mRNA in plasma exosomes were analyzed and validated using high-throughput RNA sequencing and qRT-PCR. Pathway enrichment analysis were performed on differentially expressed transcripts to screen for target lncRNAs and genes. Multivariate logistic regression models were used to construct clinical predictive models. The receiver operating characteristic curve was used to analyze the predictive value, with an 184-sample external database validated.

RESULTS

132 lncRNAs and 459 mRNAs were significantly changed in plasma exosomes of MCI patients compared to healthy controls. LINC001380, ENST00000484033, and ENST00000531087 were screened as candidate exo-lncRNAs for predicting MCI. In logistic regression models, odds ratios and 95%CI for target exo-IncRNAs in MCI patients compared to healthy controls were 1.15(1.03-1.28) for LINC001380, 1.21(1.10-1.34) for ENST00000484033, and 1.23(1.08-1.40) for ENST00000531087, respectively. ROC curve analysis showed that the AUC of the combined predicted probability of target lncRNAs was 70.0 %(64.1 %-76.0 %). In the external database, the AUC for the target genes ATP2A2 and PSEN1 was 69.5 %(61.8 %-77.15 %).

CONCLUSION

This study provided evidence for the specific expression of plasma exosomal lncRNAs in MCI and its possible biological mechanism. The combined detection of the expression levels of lncRNA-LINC001380, lncRNA-ENST00000484033, and lncRNA-ENST00000531087 in plasma exosomes may provide early diagnosis and prevention of cognitive impairment.

The Role of Small Extracellular Vesicles Derived from Glial Cells in the Central Nervous System under both Normal and Pathological Conditions

In recent decades, researchers and clinicians have increasingly focused on glial cell function. One of the primary mechanisms influencing these functions is through extracellular vesicles (EVs), membrane-bound particles released by cells that are essential for intercellular communication. EVs can be broadly categorized into four main types based on their size, origin, and biogenesis: large EVs, small EVs (sEVs), autophagic EVs, and apoptotic bodies. Small EVs (sEVs) are involved in various physiological and pathological processes such as immune responses, angiogenesis, and cellular communication, primarily by transferring proteins, lipids, and nucleic acids to recipient cells. Interactions among glial cells mediated by small EVs can significantly modulate cell polarization and influence glial behavior through miRNA transfer. This communication, facilitated by small EVs in glial cells, is crucial for neuroinflammation, immune responses, and disease progression. This comprehensive review focuses on driven by glial small EVs, highlighting their roles in transporting biomolecules and modulating the functions of recipient cells. Furthermore, we provide an in-depth overview of the specific contributions of small EVs derived from three principal types of glial cells: oligodendrocytes, astrocytes, and microglia.

A game of hide-and-seek: how extracellular vesicles evade the immune system

Extracellular vesicles (EVs) are heterogeneously sized, cell-derived nanoparticles operating as proficient mediators of intercellular communication. They are produced by normal as well as diseased cells and carry a variety of cargo. While the molecular details of EV biology have been worked out over the past two decades, one question that continues to intrigue many is how are EVs able to evade the phagocytic immune cells while also being effectively internalized by the target cell or tissue. While some of the components that facilitate this process have started to be identified, many mechanisms are yet to be dissected. This review summarises some of the key mechanisms that cancer cell-derived and viral infected cell-derived EVs utilize to evade the immune system. It will discuss the diverse cloaking mechanisms, in the form of membrane proteins and cargo content that these EVs utilize to enhance pathogenesis. Further, it will highlight the different strategies that have been used to design EVs to escape the immune system, thereby increasing their circulation time with no major toxic effects in vivo. An understanding of the potential EV components that allow better immune evasion can be used to bioengineer EVs with better circulation times for therapeutic purposes.

Fundamental Neurochemistry Review: Lipids across microglial states

The capacity of immune cells to alter their function based on their metabolism is the basis of the emerging field of immunometabolism. Microglia are the resident innate immune cells of the central nervous system, and it is a current focus of the field to investigate how alterations in their metabolism impact these cells. Microglia have the ability to utilize lipids, such as fatty acids, as energy sources, but also alterations in lipids can impact microglial form and function. Recent studies highlighting different microglial states and transcriptional signatures have highlighted modifications in lipid processing as defining these states. This review highlights these recent studies and uses these altered pathways to discuss the current understanding of lipid biology in microglia. The studies highlighted here review how lipids may alter microglial phagocytic functioning or alter their pro- and anti-inflammatory balance. These studies provide a foundation by which lipid supplementation or diet alterations could influence microglial states and function. Furthermore, targets modulating microglial lipid metabolism may provide new treatment avenues.

Mapping the current trends and hotspots of extracellular vesicles in Alzheimer's disease: a bibliometric analysis

Background

Extracellular vesicles (EVs) have garnered significant attention in Alzheimer's disease (AD) research over the past decade, largely due to their potential in diagnostics and therapeutics. Although the investigation of EVs in AD is a relatively recent endeavor, a comprehensive bibliometric analysis of this rapidly growing field has yet to be conducted.

Methods

This study aims to elucidate and synthesize the relationship between EVs and AD, offering critical insights to guide future research and expand therapeutic possibilities. Over the past 10-15 years, substantial progress has been made in this domain. Through bibliometric techniques, this analysis assesses research performance by examining scientific publications and metrics, including productivity indicators, impact measurements, data mining, and visualization tools.

Results

A total of 602 publications were analyzed using various online platforms for bibliometric analysis. Notably, the number of publications began to increase rapidly in 2018, with China and the United States emerging as leaders in this research area. The National Institute on Aging produced the highest number of publications among institutions. The Journal of Molecular Sciences and the Journal of Biological Chemistry were the most prolific and most frequently cited journals, respectively. Among individual contributors, Dimitrios Kapogiannis was identified as the most productive author, while Edward J. Goetzl was the most co-cited. The most prevalent keywords included "neurodegenerative diseases," "exosomes," "blood biomarkers," "amyloid beta," "microglia," and "tau protein." Current research hotspots involve microRNA dysregulation, oxidative stress, carboxyl-terminal fragments, small EVs, and mesenchymal stem cell-derived EVs, indicating key areas for future research.

Conclusion

Research on microRNA dysregulation, oxidative stress, carboxyl-terminal fragments, small EVs, and mesenchymal stem cell-derived EVs represents a critical frontier in the study of Alzheimer's disease. The role of EV-mediated neuroinflammation in AD is a focal point of ongoing investigation and will likely shape future developments in the field.

Understanding Aβ25-35 peptide altered exosomal proteome and associated pathways linked with the Alzheimer's disease pathogenesis using human neuroblastoma SH-SY5Y Cells

The central nervous system (CNS) involves a complex interplay of communications between the neurons and various glial cells, which is crucial for brain functions. The major interactomes are exosomes that transmit sundry molecules (DNA, miRNAs, and proteins) between the cells and thus alter cell physiology. Exosomes can act as neuroprotective or neurodegenerative agents depending on the microenvironment of cells secreting them. Therefore, revealing exosome proteome becomes important to understand donor cells' physiology and its effect on the recipient cell. In this study, oxidative stress was induced by Aβ25-35 in the human neuroblastoma SH-SY5Y cells and the protective effects of phytochemical ferulic acid (FA) were evaluated alone and in combination with Aβ25-35 (pre-treated for 3 h before Aβ25-35 exposure) and proteome of their secreted exosomes was analyzed, which was carried out via a high-resolution LC-MS Triple-ToF and further network-based analysis has been carried out using various bioinformatics tools. The proteomic profiling enlightened the multiple roles of exosomes as proteins associated with the various pathways advocate that exosomes can mediate a wide range of effects, from normal physiological processes like synaptic plasticity, neuronal metabolic support, nerve regeneration, DNA repair, axon guidance, and long-term potentiation (LTP) to abnormal pathological processes like inflammatory responses, oxidative stress, apoptosis, and formation of neutrophil extracellular traps (NETs). On comparison, treatment with Aβ25-35 resulted in a significant modulation of the exosomal proteome, promoting pathways associated with neurodegeneration. Conversely, the phytochemical FA displayed a protective effect by effectively countering Aβ25-35-induced oxidative stress responses linked with neurodegeneration, as seen in Alzheimer's disease (AD). Taken together, this study highlights the dual role of exosomes in physiological and pathophysiological neurodegenerative AD, which intricately depend on the particular cellular milieu.

The role of autophagy in brain health and disease: Insights into exosome and autophagy interactions

Effective management of cellular components is essential for maintaining brain health, and studies have identified several crucial biological processes in the brain. Among these, autophagy and the role of exosomes in cellular communication are critical for brain health and disease. The interaction between autophagy and exosomes in the nervous system, as well as their contributions to brain damage, have garnered significant attention. This review summarizes that exosomes and their cargoes have been implicated in the autophagy process in the pathophysiology of nervous system diseases. Furthermore, the onset and progression of neurological disorders may be affected by autophagy regulation of the secretion and release of exosomes. These findings may provide new insights into the potential mechanism by which autophagy mediates different exosome secretion and release, as well as the valuable biomedical applications of exosomes in the prevention and treatment of various brain diseases by targeting autophagy.

Exosome Cargo in Neurodegenerative Diseases: Leveraging Their Intercellular Communication Capabilities for Biomarker Discovery and Therapeutic Delivery

The inexorable progression of neurodegenerative diseases (NDs), including Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and multiple sclerosis, is closely related to irreversible brain decline. Accurately characterizing pathophysiological features and identifying reliable biomarkers for early diagnosis and optimized treatment are critical. Hindered by the blood-brain barrier (BBB), obtaining sensitive monitoring indicators for disease progression and achieving efficient drug delivery remain significant challenges. Exosomes, endogenous nanoscale vesicles that carry key bioactive substances, reflect the intracellular environment and play an important role in cell signaling. They have shown promise in traversing the BBB, serving dual roles as potential biomarkers for NDs and vehicles for targeted drug delivery. However, the specific mechanisms by which exosome influence NDs are not fully understood, necessitating further investigation into their attributes and functionalities in the context of NDs. This review explores how exosomes mediate multifaceted interactions, particularly in exacerbating pathogenic processes such as oxidative stress, neuronal dysfunction, and apoptosis integral to NDs. It provides a comprehensive analysis of the profound impact of exosomes under stress and disease states, assessing their prospective utility as biomarkers and drug delivery vectors, offering new perspectives for tackling these challenging diseases.

Lycium ruthenicum Murray derived exosome-like nanovesicles inhibit Aβ-induced apoptosis in PC12 cells via MAPK and PI3K/AKT signaling pathways

Plant-derived exosome-like nanovesicles (ELNs) are nano-sized vesicles extracted from edible plants. Lycium ruthenicum Murray (LRM) has been gaining increasing attention due to its nutritional and medicinal value, but the ELNs in LRM has not been reported. In this study, LRM-ELNs were obtained, and the proteins, lipids, microRNAs (miRNAs) and active components in LRM tissues and LRM-ELNs was analyzed by LC-MS/MS, LC-MS, high-throughput sequencing techniques, and physical and chemical analysis. LRM-ELNs can be uptaken by PC12 cells through macropinocytosis and caveolin-mediated endocytosis primarily. Transcriptomic and western blot experiments indicate that LRM-ELNs can inhibit Aβ-induced apoptosis in PC12 cells through the MAPK and PI3K/AKT signaling pathways, with miRNAs playing a crucial role. These results indicate that LRM-ELNs have the protection effect on PC12 cells and can be considered as dietary supplements for alleviating neurodegenerative diseases.

Exosomes in multiple sclerosis and Alzheimer's disease - Adversary and ally

Neuroinflammation and the resulting neurodegeneration is a big challenge for the healthcare system, especially with the aging population. Neuroinflammation can result from a variety of insults to the central nervous system leading to an interplay between immune and brain cells that sustains chronic inflammation and injures neural cells. One facilitator of this toxic interplay are exosomes. Exosomes are nano-sized, bilayer lipid vesicles secreted by cells containing proteins, nucleic acids and lipids. Because exosomes can be internalized by other cells, their contents can elicit inflammatory responses and trigger toxicities in recipient cells. On the flip side, exosomes can act as therapeutic vehicles carrying protective cargo to maintain homeostasis. This review discusses exosome biogenesis, composition, and its role in neuroinflammation and neurodegeneration in the context of multiple sclerosis and Alzheimer's disease. The emerging roles of exosomes as biomarkers of neurologic diseases and as therapeutic delivery vehicles are also discussed. With all of these varying roles, interest and excitement in exosomes continue to grow exponentially and their promise as brain therapeutics is only beginning to be explored and harnessed.

Regulation of cellular and systemic sphingolipid homeostasis

One hundred and fifty years ago, Johann Thudichum described sphingolipids as unusual "Sphinx-like" lipids from the brain. Today, we know that thousands of sphingolipid molecules mediate many essential functions in embryonic development and normal physiology. In addition, sphingolipid metabolism and signalling pathways are dysregulated in a wide range of pathologies, and therapeutic agents that target sphingolipids are now used to treat several human diseases. However, our understanding of sphingolipid regulation at cellular and organismal levels and their functions in developmental, physiological and pathological settings is rudimentary. In this Review, we discuss recent advances in sphingolipid pathways in different organelles, how secreted sphingolipid mediators modulate physiology and disease, progress in sphingolipid-targeted therapeutic and diagnostic research, and the trans-cellular sphingolipid metabolic networks between microbiota and mammals. Advances in sphingolipid biology have led to a deeper understanding of mammalian physiology and may lead to progress in the management of many diseases.

Extracellular vesicles from mesenchymal stem cells alter gut microbiota and improve neuroinflammation and motor impairment in rats with mild liver damage

Gut microbiota perturbation and motor dysfunction have been reported in steatosis patients. Rats with mild liver damage (MLD) show motor dysfunction mediated by neuroinflammation and altered GABAergic neurotransmission in the cerebellum. The extracellular vesicles (EV) from mesenchymal stem cells (MSC) have emerged as a promising therapeutic proxy whose molecular basis relies partly upon TGFβ action. This study aimed to assess if MSC-EVs improve motor dysfunction in rats with mild liver damage and analyze underlying mechanisms, including the role of TGFβ, cerebellar neuroinflammation and gut microbiota. MLD in rats was induced by carbon tetrachloride administration and EVs from normal (C-EVs) or TGFβ-siRNA treated MSCs (T-EV) were injected. Motor coordination, locomotor gait, neuroinflammation and TNF-α-activated pathways modulating GABAergic neurotransmission in the cerebellum, microbiota composition in feces and microbial-derived metabolites in plasma were analyzed. C-EVs reduced glial and TNFα-P2X4-BDNF-TrkB pathway activation restoring GABAergic neurotransmission in the cerebellum and improving motor coordination and all the altered gait parameters. T-EVs also improved motor coordination and some gait parameters, but the mechanisms involved differed from those of C-EVs. MLD rats showed increased content of some Bacteroides species in feces, correlating with decreased kynurenine aside from motor alterations. These alterations were all normalized by C-EVs, whereas T-EVs only restored kynurenine levels. Our results support the value of MSC-EVs on improving motor dysfunction in MLD and unveil a possible mechanism by which altered microbiota may contribute to neuroinflammation and motor impairment. Some of the underlying mechanisms are TGFβ-dependent.

Present and future use of exosomes containing proteins and RNAs in neurodegenerative diseases for synaptic function regulation: A comprehensive review

Neurodegenerative diseases (NDDs) are increasingly prevalent with global aging, demanding effective treatments. Exosomes, which contain biological macromolecules such as RNA (including miRNAs) and proteins like α-synuclein, tau, and amyloid-beta, are gaining attention as innovative therapeutics. This comprehensive review systematically explores the potential roles of exosomes in NDDs, with a particular focus on their role in synaptic dysfunction. We present the synaptic pathophysiology of NDDs and discuss the mechanisms of exosome formation, secretion, and action. Subsequently, we review the roles of exosomes in different types of NDDs, such as Alzheimer's disease and Parkinson's disease, with a special focus on their regulation of synaptic function. In addition, we explore the potential use of exosomes as biomarkers, as well as the challenges and opportunities in their clinical application. We provide perspectives on future research directions and development trends to provide a more comprehensive understanding of and guidance for the application of exosomes in the treatment of NDDs. In conclusion, exosomes rich in biological macromolecules, as a novel therapeutic strategy, have opened up new possibilities for the treatment of NDDs and brought new hope to patients.

Exosomes: A Cellular Communication Medium That Has Multiple Effects On Brain Diseases

Exosomes, as membranous vesicles generated by multiple cell types and secreted to extracellular space, play a crucial role in a range of brain injury-related brain disorders by transporting diverse proteins, RNA, DNA fragments, and other functional substances. The nervous system's pathogenic mechanisms are complicated, involving pathological processes like as inflammation, apoptosis, oxidative stress, and autophagy, all of which result in blood-brain barrier damage, cognitive impairment, and even loss of normal motor function. Exosomes have been linked to the incidence and progression of brain disorders in recent research. As a result, a thorough knowledge of the interaction between exosomes and brain diseases may lead to the development of more effective therapeutic techniques that may be implemented in the clinic. The potential role of exosomes in brain diseases and the crosstalk between exosomes and other pathogenic processes were discussed in this paper. Simultaneously, we noted the delicate events in which exosomes as a media allow the brain to communicate with other tissues and organs in physiology and disease, and compiled a list of natural compounds that modulate exosomes, in order to further improve our understanding of exosomes and propose new ideas for treating brain disorders.

Extracellular vesicle therapy in neurological disorders

Extracellular vesicles (EVs) are vital for cell-to-cell communication, transferring proteins, lipids, and nucleic acids in various physiological and pathological processes. They play crucial roles in immune modulation and tissue regeneration but are also involved in pathogenic conditions like inflammation and degenerative disorders. EVs have heterogeneous populations and cargo, with numerous subpopulations currently under investigations. EV therapy shows promise in stimulating tissue repair and serving as a drug delivery vehicle, offering advantages over cell therapy, such as ease of engineering and minimal risk of tumorigenesis. However, challenges remain, including inconsistent nomenclature, complex characterization, and underdeveloped large-scale production protocols. This review highlights the recent advances and significance of EVs heterogeneity, emphasizing the need for a better understanding of their roles in disease pathologies to develop tailored EV therapies for clinical applications in neurological disorders.

Extracellular Vesicles: The Next Generation of Biomarkers and Treatment for Central Nervous System Diseases

It has been widely established that the characterization of extracellular vesicles (EVs), particularly small EVs (sEVs), shed by different cell types into biofluids, helps to identify biomarkers and therapeutic targets in neurological and neurodegenerative diseases. Recent studies are also exploring the efficacy of mesenchymal stem cell-derived extracellular vesicles naturally enriched with therapeutic microRNAs and proteins for treating various diseases. In addition, EVs released by various neural cells play a crucial function in the modulation of signal transmission in the brain in physiological conditions. However, in pathological conditions, such EVs can facilitate the spread of pathological proteins from one brain region to the other. On the other hand, the analysis of EVs in biofluids can identify sensitive biomarkers for diagnosis, prognosis, and disease progression. This review discusses the potential therapeutic use of stem cell-derived EVs in several central nervous system diseases. It lists their differences and similarities and confers various studies exploring EVs as biomarkers. Further advances in EV research in the coming years will likely lead to the routine use of EVs in therapeutic settings.

Neural stem cell-derived exosomes promote mitochondrial biogenesis and restore abnormal protein distribution in a mouse model of Alzheimer's disease

JOURNAL/nrgr/04.03/01300535-202407000-00040/figure1/v/2023-11-20T171125Z/r/image-tiff

Mitochondrial dysfunction is a hallmark of Alzheimer's disease. We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of APP/PS1 mice. Because Alzheimer's disease affects the entire brain, further research is needed to elucidate alterations in mitochondrial metabolism in the brain as a whole. Here, we investigated the expression of several important mitochondrial biogenesis-related cytokines in multiple brain regions after treatment with neural stem cell-derived exosomes and used a combination of whole brain clearing, immunostaining, and lightsheet imaging to clarify their spatial distribution. Additionally, to clarify whether the sirtuin 1 (SIRT1)-related pathway plays a regulatory role in neural stem cell-derived exosomes interfering with mitochondrial functional changes, we generated a novel nervous system-SIRT1 conditional knockout APP/PS1 mouse model. Our findings demonstrate that neural stem cell-derived exosomes significantly increase SIRT1 levels, enhance the production of mitochondrial biogenesis-related factors, and inhibit astrocyte activation, but do not suppress amyloid-β production. Thus, neural stem cell-derived exosomes may be a useful therapeutic strategy for Alzheimer's disease that activates the SIRT1-PGC1α signaling pathway and increases NRF1 and COXIV synthesis to improve mitochondrial biogenesis. In addition, we showed that the spatial distribution of mitochondrial biogenesis-related factors is disrupted in Alzheimer's disease, and that neural stem cell-derived exosome treatment can reverse this effect, indicating that neural stem cell-derived exosomes promote mitochondrial biogenesis.

Exosomes: The endogenous nanomaterials packed with potential for diagnosis and treatment of neurologic disorders

Neurologic disorders (NDs) are serious diseases that threaten public health. However, due to the complex pathogenesis and significant individual differences in traditional treatments, specific treatment methods for NDs are still lacking. Exosomes, the smallest extracellular vesicles secreted by eukaryotic cells, are receiving increasing attention in the field of NDs. They contain misfolded proteins related to various NDs, including amyloid-beta, Tau proteins, and α-synuclein, indicating their promising roles in the diagnosis and treatment of NDs. In this review, an overview of the biogenesis, composition, and biological functions of exosomes is provided. Moreover, we summarize their potential roles in the pathogenesis of three prevalent NDs (including Alzheimer's disease, Ischemic stroke, and Parkinson's disease). On this basis, the diagnostic potential and therapeutic value of exosomes carrying various bioactive molecules are discussed in detail. Also, the concerns and perspectives of exosome-based diagnosis and therapy are discussed.

CNS cell-derived exosome signatures as blood-based biomarkers of neurodegenerative diseases

Molecular biomarkers require the reproducible capture of disease-associated changes and are ideally sensitive, specific and accessible with minimal invasiveness to patients. Exosomes are a subtype of extracellular vesicles that have gained attention as potential biomarkers. They are released by all cell types and carry molecular cargo that reflects the functional state of the cells of origin. These characteristics make them an attractive means of measuring disease-related processes within the central nervous system (CNS), as they cross the blood-brain barrier (BBB) and can be captured in peripheral blood. In this review, we discuss recent progress made toward identifying blood-based protein and RNA biomarkers of several neurodegenerative diseases from circulating, CNS cell-derived exosomes. Given the lack of standardized methodology for exosome isolation and characterization, we discuss the challenges of capturing and quantifying the molecular content of exosome populations from blood for translation to clinical use.

Unveiling the Complex Role of Exosomes in Alzheimer's Disease

Alzheimer's disease (AD) is the most common neurodegenerative illness, characterized by memory loss and cognitive decline, accounting for 60-80% of dementia cases. AD is characterized by senile plaques made up of amyloid β (Aβ) protein, intracellular neurofibrillary tangles caused by hyperphosphorylation of tau protein linked with microtubules, and neuronal loss. Currently, therapeutic treatments and nanotechnological developments are effective in treating the symptoms of AD, but a cure for the illness has not yet been found. Recently, the increased study of extracellular vesicles (EVs) has led to a growing awareness of their significant involvement in neurodegenerative disorders, including AD. Exosomes are small extracellular vesicles that transport various components including messenger RNAs, non-coding RNAs, proteins, lipids, DNA, and other bioactive compounds from one cell to another, facilitating information transmission and material movement. There is growing evidence indicating that exosomes have complex functions in AD. Exosomes may have a dual role in Alzheimer's disease by contributing to neuronal death and also helping to alleviate the pathological progression of the disease. Therefore, the primary aim of this review is to outline the updated understandings on exosomes biogenesis and many functions of exosomes in the generation, conveyance, distribution, and elimination of hazardous proteins related to Alzheimer's disease. This review is intended to provide novel insights for understanding the development, specific treatment, and early detection of Alzheimer's disease.

Exploring the role of brain-derived extracellular vesicles in viral infections: from pathological insights to biomarker potential

Extracellular vesicles (EVs) are membrane-bound vesicles secreted by all cell types that play a central role in cell-to-cell communication. Since these vesicles serve as vehicles of cellular content (nucleic acids, proteins and lipids) with the potential to cross biological barriers, they represent a novel attractive window into an otherwise inaccessible organ, such as the brain. The composition of EVs is cell-type specific and mirrors the physiological condition of the cell-of-origin. Consequently, during viral infection, EVs undergo significant changes in their content and morphology, thereby reflecting alterations in the cellular state. Here, we briefly summarize the potential of brain-derived EVs as a lens into viral infection in the central nervous system, thereby: 1) uncovering underlying pathophysiological processes at play and 2) serving as liquid biopsies of the brain, representing a non-invasive source of biomarkers for monitoring disease activity. Although translating the potential of EVs from research to diagnosis poses complexities, characterizing brain-derived EVs in the context of viral infections holds promise to enhance diagnostic and therapeutic strategies, offering new avenues for managing infectious neurological diseases.

Harnessing the potential of mesenchymal stem cells-derived exosomes in degenerative diseases

Mesenchymal stem cells (MSCs) have gained attention as a promising therapeutic approach in both preclinical and clinical osteoarthritis (OA) settings. Various joint cell types, such as chondrocytes, synovial fibroblasts, osteoblasts, and tenocytes, can produce and release extracellular vesicles (EVs), which subsequently influence the biological activities of recipient cells. Recently, extracellular vesicles derived from mesenchymal stem cells (MSC-EVs) have shown the potential to modulate various physiological and pathological processes through the modulation of cellular differentiation, immune responses, and tissue repair. This review explores the roles and therapeutic potential of MSC-EVs in OA and rheumatoid arthritis, cardiovascular disease, age-related macular degeneration, Alzheimer's disease, and other degenerative diseases. Notably, we provide a comprehensive summary of exosome biogenesis, microRNA composition, mechanisms of intercellular transfer, and their evolving role in the highlight of exosome-based treatments in both preclinical and clinical avenues.

Astrocyte-Derived Extracellular Vesicles for Ischemic Stroke: Therapeutic Potential and Prospective

Stroke is a leading cause of death and disability in the world. Astrocytes are special glial cells within the central nervous system and play important roles in mediating neuroprotection and repair processes during stroke. Extracellular vesicles (EVs) are lipid bilayer particles released from cells that facilitate intercellular communication in stroke by delivering proteins, lipids, and RNA to target cells. Recently, accumulating evidence suggested that astrocyte-derived EVs (ADEVs) are actively involved in mediating numerous biological processes including neuroprotection and neurorepair in stroke and they are realized as an excellent therapeutic approach for treating stroke. In this review we systematically summarize the up-to-date research on ADEVs in stroke, and prospects for its potential as a novel therapeutic target for stroke. We also provide an overview of the effects and functions of ADEVs on stroke recovery, which may lead to developing clinically relevant therapies for stroke.

Subcellular proteomics insights into Alzheimer's disease development

Alzheimer's disease (AD), one of the most common dementias, is a neurodegenerative disease characterized by cognitive impairment and decreased judgment function. The expected number of AD patient is increasing in the context of the world's advancing medical care and increasing human life expectancy. Since current molecular mechanism studies on AD pathogenesis are incomplete, there is no specific and effective therapeutic agent. Mass spectrometry (MS)-based unbiased proteomics studies provide an effective and comprehensive approach. Many advances have been made in the study of the mechanism, diagnostic markers, and drug targets of AD using proteomics. This paper focus on subcellular level studies, reviews studies using proteomics to study AD-associated mitochondrial dysfunction, synaptic, and myelin damage, the protein composition of amyloid plaques (APs) and neurofibrillary tangles (NFTs), changes in tissue extracellular vehicles (EVs) and exosome proteome, and the protein changes in ribosomes and lysosomes. The methods of sample separation and preparation and proteomic analysis as well as the main findings of these studies are involved. The results of these proteomics studies provide insights into the pathogenesis of AD and provide theoretical resource and direction for future research in AD, helping to identify new biomarkers and drugs targets for AD.

Key developments and hotspots of exosomes in Alzheimer's disease: a bibliometric study spanning 2003 to 2023

Background

Alzheimer's disease (AD) is a degenerative illness of the central nervous system that is irreversible and is characterized by gradual behavioral impairment and cognitive dysfunction. Researches on exosomes in AD have gradually gained the attention of scholars in recent years. However, the literatures in this research area do not yet have a comprehensive visualization analysis. The aim of this work is to use bibliometrics to identify the knowledge constructs and investigate the research frontiers and hotspots related to exosomes in AD.

Methods

From January 2003 until June 2023, we searched the Web of Science Core Collection for literature on exosomes in AD. We found 585 papers total. The bibliometric study was completed using VOSviewer, the R package "bibliometrix," and CiteSpace. The analysis covered nations, institutions, authors, journals, and keywords.

Results

Following 2019, the articles on exosomes in AD increased significantly year by year. The vast majority of publications came from China and the US. The University of California System, the National Institutes of Health, and the NIH National Institute on Aging in the US were the primary research institutions. Goetzl Edward J. was frequently co-cited, while Kapogiannis Dimitrios was the most prolific author in this discipline with the greatest number of articles. Lee Mijung et al. have been prominent in the last two years in exosomes in AD. The Journal of Alzheimer's Disease was the most widely read publication, and Alzheimers & Dementia had the highest impact factor. The Journal of Biological Chemistry, Proceedings of the National Academy of Sciences of the United States of America, and Journal of Alzheimer's Disease were the three journals with more than 1,000 citations. The primary emphasis of this field was Alzheimer's disease, exosomes, and extracellular vesicles; since 2017, the number of phrases pertaining to the role of exosomes in AD pathogenesis has increased annually. "Identification of preclinical Alzheimer's disease by a profile of pathogenic proteins in neurally derived blood exosomes: a case-control study" was the reference with the greatest citing power, indicating the future steered direction in this field.

Conclusion

Using bibliometrics, we have compiled the research progress and tendencies on exosomes in Alzheimer's disease for the first time. This helps determine the objectives and paths for future study.

Exosomes in Vascular/Neurological Disorders and the Road Ahead

Neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), Huntington's disease (HD), stroke, and aneurysms, are characterized by the abnormal accumulation and aggregation of disease-causing proteins in the brain and spinal cord. Recent research suggests that proteins linked to these conditions can be secreted and transferred among cells using exosomes. The transmission of abnormal protein buildup and the gradual degeneration in the brains of impacted individuals might be supported by these exosomes. Furthermore, it has been reported that neuroprotective functions can also be attributed to exosomes in neurodegenerative diseases. The potential neuroprotective functions may play a role in preventing the formation of aggregates and abnormal accumulation of proteins associated with the disease. The present review summarizes the roles of exosomes in neurodegenerative diseases as well as elucidating their therapeutic potential in AD, PD, ALS, HD, stroke, and aneurysms. By elucidating these two aspects of exosomes, valuable insights into potential therapeutic targets for treating neurodegenerative diseases may be provided.

Endo-lysosomal dysfunction in neurodegenerative diseases: opinion on current progress and future direction in the use of exosomes as biomarkers

Over the past two decades, increased research has highlighted the connection between endosomal trafficking defects and neurodegeneration. The endo-lysosomal network is an important, complex cellular system specialized in the transport of proteins, lipids, and other metabolites, essential for cell homeostasis. Disruption of this pathway is linked to a wide range of neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, Huntington's disease and frontotemporal dementia. Furthermore, there is strong evidence that defects in this pathway create opportunities for diagnostic and therapeutic intervention. In this Opinion piece, we concisely address the role of endo-lysosomal dysfunction in five neurodegenerative diseases and discuss how future research can investigate this intracellular pathway, including extracellular vesicles with a specific focus on exosomes for the identification of novel disease biomarkers. This article is part of a discussion meeting issue 'Understanding the endo-lysosomal network in neurodegeneration'.

Engineered and Mimicked Extracellular Nanovesicles for Therapeutic Delivery

Exosomes are spherical extracellular nanovesicles with an endosomal origin and unilamellar lipid-bilayer structure with sizes ranging from 30 to 100 nm. They contain a large range of proteins, lipids, and nucleic acid species, depending on the state and origin of the extracellular vesicle (EV)-secreting cell. EVs' function is to encapsulate part of the EV-producing cell content, to transport it through biological fluids to a targeted recipient, and to deliver their cargos specifically within the aimed recipient cells. Therefore, exosomes are considered to be potential biological drug-delivery systems that can stably deliver their cargo into targeted cells. Various cell-derived exosomes are produced for medical issues, but their use for therapeutic purposes still faces several problems. Some of these difficulties can be avoided by resorting to hemisynthetic approaches. We highlight here the uses of alternative exosome-mimes involving cell-membrane coatings on artificial nanocarriers or the hybridization between exosomes and liposomes. We also detail the drug-loading strategies deployed to make them drug-carrier systems and summarize the ongoing clinical trials involving exosomes or exosome-like structures. Finally, we summarize the open questions before considering exosome-like disposals for confident therapeutic delivery.

Targeted exosome-based nanoplatform for new-generation therapeutic strategies

Exosomes, typically 30-150 nm in size, are lipid-bilayered small-membrane vesicles originating in endosomes. Exosome biogenesis is regulated by the coordination of various mechanisms whereby different cargoes (e.g. proteins, nucleic acids, and lipids) are sorted into exosomes. These components endow exosomes with bioregulatory functions related to signal transmission and intercellular communication. Exosomes exhibit substantial potential as drug-delivery nanoplatforms owing to their excellent biocompatibility and low immunogenicity. Proteins, miRNA, siRNA, mRNA, and drugs have been successfully loaded into exosomes, and these exosome-based delivery systems show satisfactory therapeutic effects in different disease models. To enable targeted drug delivery, genetic engineering and chemical modification of the lipid bilayer of exosomes are performed. Stimuli-responsive delivery nanoplatforms designed with appropriate modifications based on various stimuli allow precise control of on-demand drug delivery and can be utilized in clinical treatment. In this review, we summarize the general properties, isolation methods, characterization, biological functions, and the potential role of exosomes in therapeutic delivery systems. Moreover, the effective combination of the intrinsic advantages of exosomes and advanced bioengineering, materials science, and clinical translational technologies are required to accelerate the development of exosome-based delivery nanoplatforms.

MiR-128-3p - a gray eminence of the human central nervous system

MicroRNA-128-3p (miR-128-3p) is a versatile molecule with multiple functions in the physiopathology of the human central nervous system. Perturbations of miR-128-3p, which is enriched in the brain, contribute to a plethora of neurodegenerative disorders, brain injuries, and malignancies, as this miRNA is a crucial regulator of gene expression in the brain, playing an essential role in the maintenance and function of cells stemming from neuronal lineage. However, the differential expression of miR-128-3p in pathologies underscores the importance of the balance between its high and low levels. Significantly, numerous reports pointed to miR-128-3p as one of the most depleted in glioblastoma, implying it is a critical player in the disease's pathogenesis and thus may serve as a therapeutic agent for this most aggressive form of brain tumor. In this review, we summarize the current knowledge of the diverse roles of miR-128-3p. We focus on its involvement in the neurogenesis and pathophysiology of malignant and neurodegenerative diseases. We also highlight the promising potential of miR-128-3p as an antitumor agent for the future therapy of human cancers, including glioblastoma, and as the linchpin of brain development and function, potentially leading to the development of new therapies for neurological conditions.

Extracellular vesicle proteome unveils cathepsin B connection to Alzheimer's disease pathogenesis

Extracellular vesicles (EVs) are membrane vesicles that are released extracellularly and considered to be implicated in the pathogenesis of neurodegenerative diseases including Alzheimer's disease. Here, CSF EVs of 16 ATN-classified cases were subjected to quantitative proteome analysis. In these CSF EVs, levels of 11 proteins were significantly altered during the ATN stage transitions (P < 0.05 and fold-change > 2.0). These proteins were thought to be associated with Alzheimer's disease pathogenesis and represent candidate biomarkers for pathogenic stage classification. Enzyme-linked immunosorbent assay analysis of CSF and plasma EVs revealed altered levels of cathepsin B (CatB) during the ATN transition (seven ATN groups in validation set, n = 136). The CSF and plasma EV CatB levels showed a negative correlation with CSF amyloid-β42 concentrations. This proteomic landscape of CSF EVs in ATN classifications can depict the molecular framework of Alzheimer's disease progression, and CatB may be considered a promising candidate biomarker and therapeutic target in Alzheimer's disease amyloid pathology.

The immunomodulatory effects of mesenchymal stem cell-derived extracellular vesicles in Alzheimer's disease

Neuroinflammation has been identified as another significant pathogenic factor in Alzheimer's disease following Aβ amyloid deposition and tau protein hyperphosphorylation, activated in the central nervous system by glial cells in response to injury-related and pathogen-related molecular patterns. Moderate glial cell activity can be neuroprotective; however, excessive glial cell activation advances the pathology of Alzheimer's disease and is accompanied by structural changes in the brain interface, with peripheral immune cells entering the brain through the blood-brain barrier, creating a vicious circle. The immunomodulatory properties of mesenchymal stem cells (MSCs) are primarily conveyed through extracellular vesicles (EVs). MSC-EVs participate in chronic inflammatory and immune processes by transferring nucleic acids, proteins and lipids from the parent cell to the recipient cell, thus MSC-EVs retain their immunomodulatory capacity while avoiding the safety issues associated with living cell therapy, making them a promising focus for immunomodulatory therapy. In this review, we discuss the modulatory effects of MSC-EVs on Alzheimer's disease-associated immune cells and the mechanisms involved in their treatment of the condition. We have found a clinical trial of MSC-EVs in Alzheimer's disease treatment and outlined the challenges of this approach. Overall, MSC-EVs have the potential to provide a safe and effective treatment option for Alzheimer's disease by targeting neuroinflammation.

FTIR Spectroscopy and Blood-Derived Extracellular Vesicles Duo in Alzheimer's Disease

Background

Alzheimer's disease (AD) diagnosis is difficult, and new accurate tools based on peripheral biofluids are urgently needed. Extracellular vesicles (EVs) emerged as a valuable source of biomarker profiles for AD, since their cargo is disease-specific and these can be easily isolated from easily accessible biofluids, as blood. Fourier Transform Infrared (FTIR) spectroscopy can be employed to analyze EVs and obtain the spectroscopic profiles from different regions of the spectra, simultaneously characterizing carbohydrates, nucleic acids, proteins, and lipids.

Objective

The aim of this study was to identify blood-derived EVs (bdEVs) spectroscopic signatures with AD discriminatory potential.

Methods

Herein, FTIR spectra of bdEVs from two biofluids (serum and plasma) and distinct sets of Controls and AD cases were acquired, and EVs' spectra analyzed.

Results

Analysis of bdEVs second derivative peaks area revealed differences between Controls and AD cases in distinct spectra regions, assigned to carbohydrates and nucleic acids, amides, and lipids.

Conclusions

EVs' spectroscopic profiles presented AD discriminatory value, supporting the use of bdEVs combined with FTIR as a screening or complementary tool for AD diagnosis.

Stem Cell Interventions in Neurology: From Bench to Bedside

Stem cell therapies are progressively redefining the treatment landscape for a spectrum of neurological and age-related disorders. This review discusses the molecular and functional attributes of stem cells, emphasizing the roles of neural stem cells and mesenchymal stem cells in the context of neurological diseases such as stroke, multiple sclerosis, amyotrophic lateral sclerosis, traumatic brain injury, Parkinson's disease, and Alzheimer's disease. The review also explores the potential of stem cells in addressing the aging process. The paper analyzes stem cells' intrinsic properties of self-renewal, differentiation, and paracrine effects, alongside the importance of laboratory-modified stem cells like induced pluripotent stem cells and transgenic stem cells. Insights into disease-specific stem cell treatments are offered, reviewing both successes and challenges in the field. This includes the translational difficulties from rodent studies to human trials. The review concludes by acknowledging the uncharted territories that warrant further investigation, emphasizing the potential roles of stem cell-derived exosomes and indole-related molecules, and aiming at providing a basic understanding of stem cell therapies.

Biomembrane-Derived Nanoparticles in Alzheimer's Disease Therapy: A Comprehensive Review of Synthetic Lipid Nanoparticles and Natural Cell-Derived Vesicles

Current therapies for Alzheimer's disease used in the clinic predominantly focus on reducing symptoms with limited capability to control disease progression; thus, novel drugs are urgently needed. While nanoparticles (liposomes, high-density lipoprotein-based nanoparticles) constructed with synthetic biomembranes have shown great potential in AD therapy due to their excellent biocompatibility, multifunctionality and ability to penetrate the BBB, nanoparticles derived from natural biomembranes (extracellular vesicles, cell membrane-based nanoparticles) display inherent biocompatibility, stability, homing ability and ability to penetrate the BBB, which may present a safer and more effective treatment for AD. In this paper, we reviewed the synthetic and natural biomembrane-derived nanoparticles that are used in AD therapy. The challenges associated with the clinical translation of biomembrane-derived nanoparticles and future perspectives are also discussed.

Proteomic comparison between non-purified cerebrospinal fluid and cerebrospinal fluid-derived extracellular vesicles from patients with Alzheimer's, Parkinson's and Lewy body dementia

Dementia is a leading cause of death worldwide, with increasing prevalence as global life expectancy increases. The most common neurodegenerative disorders are Alzheimer's disease (AD), dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD). With this study, we took an in-depth look at the proteome of the (non-purified) cerebrospinal fluid (CSF) and the CSF-derived extracellular vesicles (EVs) of AD, PD, PD-MCI (Parkinson's disease with mild cognitive impairment), PDD and DLB patients analysed by label-free mass spectrometry. This has led to the discovery of differentially expressed proteins that may be helpful for differential diagnosis. We observed a greater number of differentially expressed proteins in CSF-derived EV samples (N = 276) compared to non-purified CSF (N = 169), with minimal overlap between both datasets. This finding suggests that CSF-derived EV samples may be more suitable for the discovery phase of a biomarker study, due to the removal of more abundant proteins, resulting in a narrower dynamic range. As disease-specific markers, we selected a total of 39 biomarker candidates identified in non-purified CSF, and 37 biomarker candidates across the different diseases under investigation in the CSF-derived EV data. After further exploration and validation of these proteins, they can be used to further differentiate between the included dementias and may offer new avenues for research into more disease-specific pharmacological therapeutics.

Therapeutic efficacy and promise of stem cell-derived extracellular vesicles in Alzheimer's disease and other aging-related disorders

The term extracellular vesicles (EVs) refers to a variety of heterogeneous nanovesicles secreted by almost all cell types, primarily for intercellular communication and maintaining cellular homeostasis. The role of EVs has been widely reported in the genesis and progression of multiple pathological conditions, and these vesicles are suggested to serve as 'liquid biopsies'. In addition to their use as biomarkers, EVs secreted by specific cell types, especially with stem cell properties, have shown promise as cell-free nanotherapeutics. Stem cell-derived EVs (SC-EVs) have been increasingly used as an attractive alternative to stem cell therapies and have been reported to promote regeneration of aging-associated tissue loss and function. SC-EVs treatment ameliorates brain and peripheral aging, reproductive dysfunctions and inhibits cellular senescence, thereby reversing several aging-related disorders and dysfunctions. The anti-aging therapeutic potential of SC-EVs depends on multiple factors, including the type of stem cells, the age of the source stem cells, and their physiological state. In this review, we briefly describe studies related to the promising effects of SC-EVs against various aging-related pathologies, and then we focus in-depth on the therapeutic benefits of SC-EVs against Alzheimer's disease, one of the most devastating neurodegenerative diseases in elderly individuals. Numerous studies in transgenic mouse models have reported the usefulness of SC-EVs in targeting the pathological hallmarks of Alzheimer's disease, including amyloid plaques, neurofibrillary tangles, and neuroinflammation, leading to improved neuronal protection, synaptic plasticity, and cognitive measures. Cell culture studies have further identified the underlying molecular mechanisms through which SC-EVs reduce amyloid beta (Aβ) levels or shift microglia phenotype from pro-inflammatory to anti-inflammatory state. Interestingly, multiple routes of administration, including nasal delivery, have confirmed that SC-EVs could cross the blood-brain barrier. Due to this, SC-EVs have also been tested to deliver specific therapeutic cargo molecule/s (e.g., neprilysin) to the brain. Despite these promises, several challenges related to quality control, scalability, and biodistribution remain, hindering the realization of the vast clinical promise of SC-EVs.

Extracellular Vesicle-Serpine-1 Affects Neural Progenitor Cell Mitochondrial Networks and Synaptic Density: Modulation by Amyloid Beta and HIV-1

Brain endothelial extracellular vesicles carrying amyloid beta (EV-Aβ) can be transferred to neural progenitor cells (NPCs) leading to NPC dysfunction. However, the events involved in this EV-mediated Aβ pathology are unclear. EV-proteomics studies identified Serpine-1 (plasminogen activator inhibitor 1, PAI-1) as a major connecting "hub" on several protein-protein interaction maps. Serpine-1 was described as a key player in Aβ pathology and was linked to HIV-1 infection as well. Therefore, the aim of this work was to address the hypothesis that Serpine-1 can be transferred via EVs from brain endothelial cells (HBMEC) to NPCs and contribute to NPC dysfunction. HBMEC concentrated and released Serpine-1 via EVs, the effect that was potentiated by HIV-1 and Aβ. EVs loaded with Serpine-1 were readily taken up by NPCs, and HIV-1 enhanced this event. Interestingly, a highly specific Serpine-1 inhibitor PAI039 increased EV-Aβ transfer to NPCs in the presence of HIV-1. PAI039 also partially blocked mitochondrial network morphology alterations in the recipient NPCs, which developed mainly after HIV + Aβ-EV transfer. PAI039 partly attenuated HIV-EV-mediated decreased synaptic protein levels in NPCs, while increased synaptic protein levels in NPC projections. These findings contribute to a better understanding of the complex mechanisms underlying EV-Serpine-1 related Aβ pathology in the context of HIV infection. They are relevant to HIV-1 associated neurocognitive disorders (HAND) in an effort to elucidate the mechanisms of neuropathology in HIV infection.