Role of Exosomes/Microvesicles in the Nervous System and Use in Emerging Therapies

Abstract

Extracellular membrane vesicles (EMVs) are nanometer sized vesicles, including exosomes and microvesicles capable of transferring DNAs, mRNAs, microRNAs, non-coding RNAs, proteins, and lipids among cells without direct cell-to-cell contact, thereby representing a novel form of intercellular communication. Many cells in the nervous system have been shown to release EMVs, implicating their active roles in development, function, and pathologies of this system. While substantial progress has been made in understanding the biogenesis, biophysical properties, and involvement of EMVs in diseases, relatively less information is known about their biological function in the normal nervous system. In addition, since EMVs are endogenous vehicles with low immunogenicity, they have also been actively investigated for the delivery of therapeutic genes/molecules in treatment of cancer and neurological diseases. The present review summarizes current knowledge about EMV functions in the nervous system under both physiological and pathological conditions, as well as emerging EMV-based therapies that could be applied to the nervous system in the foreseeable future.

Exosomes in stroke pathogenesis and therapy

“…Exosomes are endosome-derived small membrane vesicles, approximately 30 to 100 nm in diameter, and are released into extracellular fluids by cells in all living systems (12,13). They are present in biofluids such as blood and the cerebrospinal fluid (CSF) (13).…”

Diagnostic Potential of Neural Exosome Cargo as Biomarkers for Acute Brain Injury

“…Originally thought to be a cellular mechanism for disposal, exosomes are now known to have important functions including immune regulation, modulation of inflammation, cell‐to‐cell signaling, and angiogenesis. Exosomes are known to be released from living neurons as part of normal neuronal development as important drivers of synaptic plasticity 21, 22, 23. Increased levels of exosomes and microparticles have been reported to be released from cells after traumatic brain injury24 and stroke,25 which may increase peripheral exosome yields.…”

Exosomes in developmental signalling

“…Because presynaptic RAB11 knockdown prevents the transfer of Wingless across the NMJ, it was suggested that WLS and Wingless could be loaded together on exosomes that would then traverse the NMJ (Koles et al, 2012). Other studies have also suggested a role for exosomes in neuronal development and function (Lai and Breakefield, 2012), including axon pathfinding (Campbell and Peterson, 1993) and the regulation of myelination (Bakhti et al, 2011).…”