✍️ Author: Dr Eleni Christoforidou
🕒 Approximate reading time: 4 minutes
Extracellular vesicles (EVs), minute membrane-bound particles secreted by cells, have recently stepped into the limelight in the realm of neuroscience. These nanoscopic entities are now understood to be pivotal in neuronal communication and may also be implicated in certain pathological conditions. Here's a look into their intriguing roles.
Extracellular vesicles include exosomes, microvesicles, and apoptotic bodies. These vesicles encapsulate a snapshot of their cell of origin, carrying proteins, lipids, and various nucleic acids. Their ability to transfer these molecules to recipient cells underlies their role in cell-to-cell communication.
In the central nervous system, neurons and glial cells use EVs as a means to communicate. For instance:
Synaptic Plasticity: EVs can transfer receptors and other proteins between neurons, influencing synaptic strength and plasticity.
Glial Communication: Astrocytes and microglia utilise EVs to relay signals to neurons and other glial cells, modulating inflammation and synaptic activity.
Certain EVs have been found to have neuroprotective properties. For example, they can transfer molecules that promote neuronal survival, aid in repairing damaged neural circuits, or provide nutrients to stressed cells.
Unfortunately, the story of EVs isn't solely a tale of beneficial interactions:
Spreading Pathology: It’s believed that pathogenic proteins, like those involved in Alzheimer's or Parkinson’s disease, can hitch a ride on EVs, potentially contributing to disease propagation.
Chronic Inflammation: In some neurodegenerative conditions, glial-derived EVs may exacerbate inflammation, accelerating neuronal damage.
Given their ability to cross the blood-brain barrier, EVs are being explored as potential delivery systems for therapeutic agents. Moreover, their potential role in pathology suggests that modulating EV content or release could be a novel therapeutic avenue for neurodegenerative diseases.
Extracellular vesicles serve as dynamic messengers in the nervous system, both maintaining its delicate balance and, at times, contributing to its dysfunction. As we continue to unravel their intricacies, the importance of these tiny vesicles in the grand narrative of neuroscience becomes undeniably apparent.