Role of Extracellular Vesicles in Glia-Neuron Intercellular Communication

Abstract

Cross talk between glia and neurons is crucial for a variety of biological functions, ranging from nervous system development, axonal conduction, synaptic transmission, neural circuit maturation, to homeostasis maintenance. Extracellular vesicles (EVs), which were initially described as cellular debris and were devoid of biological function, are now recognized as key components in cell-cell communication and play a critical role in glia-neuron communication. EVs transport the proteins, lipids, and nucleic acid cargo in intercellular communication, which alters target cells structurally and functionally. A better understanding of the roles of EVs in glia-neuron communication, both in physiological and pathological conditions, can aid in the discovery of novel therapeutic targets and the development of new biomarkers. This review aims to demonstrate that different types of glia and neuronal cells secrete various types of EVs, resulting in specific functions in intercellular communications.

Keywords: cellular cargo; extracellular vesicles; glia; intercellular communication; neuron.

FIGURE 1

Different types of extracellular vesicles (EVs). EVs can be categorized into three main classes based on their mode of origin: (i) exosomes, (ii) microvesicles, and (iii) apoptotic bodies. An EV cargo consists of a specific set of proteins, lipids, and nucleic acids, and neighboring cells use EVs as a method of paracrine transfer of molecular signals between cells. Figure reproduced from Koniusz et al. (2016).

FIGURE 2

Extracellular Vesicle-mediated glia-neuron intercellular communication in the central nervous system (CNS). In the CNS, cross talk between glia and neurons is crucial for a variety of biological functions, ranging from neuroprotection, neural circuit maturation, homeostasis maintenance, and synaptic function modulation. Solid arrows indicate the exchange of EVs between different glial cells and neurons.