Specific Role of Extracellular Vesicles in Controlling Neuroinflammation in Alzheimer’s and Parkinson’s Disease: Is an EV-Based Therapy Possible?

Neurodegenerative diseases are associated with acute or chronic inflammation and death of neurons initiated by inflammatory cytokines and chemokines produced by brain resident glial or infiltrated immune cells in the affected brain parts. The cross-communications between neurons and glial cells are not static or mediated only by cell–cell interaction, neurotransmitters, or small peptides but are also controlled by small vesicles collectively known as extracellular vesicles or EVs secreted by neuronal and non-neuronal cells. While diverse types of cargo in EVs contribute to the well-being and survival of the neurons, a subset of EVs and their cargo were found to have detrimental effects on neuron–glia communication. EVs from virus-infected cells also determine the complexity of HIV1 infection-associated neurodegeneration by communicating viral proteins and RNAs, as part of EVs secreted by infected cells, to neighboring neurons and glial cells to affect the pathogenesis of HIV-associated neurocognitive dysfunction. We have explored the recent and relevant findings that have suggested significant and specific regulatory contributions of EVs and their cargo in neurodegenerative processes in the mammalian brain. Briefly, we have also pointed out how the future therapeutic applications of EVs may be able to reverse neurodegeneration after the successful resolution of specific challenges related to EV-based therapy.