Extracellular Vesicles In Neurodegenerative Diseases Research Articles

Extracellular Vesicles in Neurodegenerative Diseases: An Update.

Neurodegenerative diseases affect millions of people worldwide. The likelihood of developing a neurodegenerative disease rises dramatically as life expectancy increases. Although it has drawn significant attention, there is still a lack of proper effective treatments for neurodegenerative disease because the mechanisms of its development and progression are largely unknown. Extracellular vesicles (EVs) are small bi-lipid layer-enclosed nanosized particles in tissues and biological fluids. EVs are emerging as novel intercellular messengers and regulate a series of biological responses. Increasing evidence suggests that EVs are involved in the pathogenesis of neurodegenerative disorders. In this review, we summarize the recent findings of EVs in neurodegenerative diseases and bring up the limitations in the field.

Promising Role of Oral Cavity Mesenchymal Stem Cell-Derived Extracellular Vesicles in Neurodegenerative Diseases.

Mesenchymal stem cells (MSCs) and mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have been regarded as the beneficial and available tools to treat various hereditary, multifactorial, acute, and chronic diseases. Mesenchymal stem cells can be extracted from numerous sources for clinical purposes while oral cavity-derived mesenchymal stem cells seem to be more effective in neuroregeneration than other sources due to their similar embryonic origins to neuronal tissues. In various studies and different neurodegenerative diseases (NDs), oral cavity mesenchymal stem cells have been applied to prove their promising capacities in disease improvement. Moreover, oral cavity mesenchymal stem cells' secretion is regarded as a novel and practical approach to neuroregeneration; hence, extracellular vesicles (EVs), especially exosomes, may provide promising results to improve CNS defects. This review article focuses on how oral cavity-derived stem cells and their extracellular vesicles can improve neurodegenerative conditions and tries to show which molecules are involved in the recovery process.

Role of Glia-Derived Extracellular Vesicles in Neurodegenerative Diseases.

Extracellular vesicles (EVs), as nano-sized vesicles secreted by almost all cells, have been recognized as the essential transmitter for cell-to-cell communication and participating in multiple biological processes. Neurodegenerative diseases (ND), such as Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis, share common mechanisms of the aggregation and propagation of distinct pathologic proteins among cells in the nervous systems and neuroinflammatory reactions mediated by glia during the pathogenic process. This feature indicates the vital role of crosstalk between neurons and glia in the pathogenesis of ND. In recent years, glia-derived EVs have been investigated as potential mediators of signals between neurons and glia, which provides a new direction and strategy for understanding ND. By a comprehensive summary, it can be concluded that glia-derived EVs have both a beneficial and/or a detrimental effect in the process of ND. Therefore, this review article conveys the role of glia-derived EVs in the pathogenesis of ND and raises current limitations of their potential application in the diagnosis and treatment of ND.

Role of extracellular vesicles in neurodegenerative diseases.

Extracellular vesicles (EVs) are heterogeneous cell-derived membranous structures that arise from the endosome system or directly detach from the plasma membrane. In recent years, many advances have been made in the understanding of the clinical definition and pathogenesis of neurodegenerative diseases, but translation into effective treatments is hampered by several factors. Current research indicates that EVs are involved in the pathology of diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD). Besides, EVs are also involved in the process of myelin formation, and can also cross the blood-brain barrier to reach the sites of CNS injury. It is suggested that EVs have great potential as a novel therapy for the treatment of neurodegenerative diseases. Here, we reviewed the advances in understanding the role of EVs in neurodegenerative diseases and addressed the critical function of EVs in the CNS. We have also outlined the physiological mechanisms of EVs in myelin regeneration and highlighted the therapeutic potential of EVs in neurodegenerative diseases.

Pathogenic and protective roles of extracellular vesicles in neurodegenerative diseases.

Neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis and polyglutamine diseases are caused by aggregation and abnormal accumulation of the disease-causative proteins in brain and spinal cord. Recent studies have suggested that proteins associated with neurodegenerative diseases are secreted and transmitted intercellularly via extracellular vesicles (EVs), which may be involved in propagation of abnormal protein accumulation and progressive degeneration in patient brains. On the other hand, it has been also reported that EVs have neuroprotective roles in these diseases, which potentially contribute to preventing aggregation formation and aberrant accumulation of the disease-associated proteins. In this review, I summarize the current understanding of the roles of EVs in neurodegenerative diseases, especially focussing on the pathogenic and neuroprotective aspects. Elucidation of these two aspects of EVs would provide insight into not only potential therapeutic targets for treatment of neurodegenerative diseases but also development of EV-based biomarkers for disease diagnostics.

Potential of Extracellular Vesicles in Neurodegenerative Diseases: Diagnostic and Therapeutic Indications.

Extracellular vesicles (EVs) are membrane-bound vesicles, including exosomes and microvesicles. EVs are nanometer sized, found in physiological fluids such as urine, blood, cerebro-spinal fluid (CSF), with a capacity of transferring various biological materials such as microRNAs, proteins, and lipids among cells without direct cell-to-cell contact. Many cells in the nervous system have been shown to release EVs. These vesicles are involved in intercellular communication and a variety of biological processes such as modulation of immune response, signal transduction, and transport of genetic materials with low immunogenicity; therefore, they have also been recently investigated for the delivery of therapeutic molecules such as siRNAs and drugs in the treatment of diseases. In addition, since EV components reflect the physiological status of the cells and tissues producing them, they can be utilized as biomarkers for early detection of various diseases. In this review, we summarize EV application, in diagnosis as biomarker sources and as a carrier tool for drug delivery in EV-based therapies in neurodegenerative diseases.

Correction to: Extracellular Vesicles in Neurodegenerative Diseases: A Double-Edged Sword.

[This corrects the article DOI: 10.1007/s13770-017-0090-x.].