Insights into the Versatile Role of Extracellular Vesicles in the Treatment of CNS Disorders

E xtracellular vesicles (EVs) are lipid bilayer-enclosed nanocarriers composed primarily of phospholipids and membrane proteins. They are released by cells into the surrounding extracellular environment and vary in size, composition, and biogenesis pathways. Beyond their natural role in intercellular communication, mediating the transfer of proteins, lipids, and nucleic acids (like mRNA and miRNA) between cells, EVs have emerged as a highly versatile and promising therapeutic platform for a range of challenging disorders, particularly those affecting the central nervous system (CNS) and various cancers. The CNS presents unique therapeutic challenges, notably the formidable blood-brain barrier (BBB), which restricts the entry of most conventional drugs. EVs, however, possess an inherent capacity to traverse this barrier, either naturally or through engineered modifications. This characteristic positions them as ideal nanocarriers for delivering therapeutic payloads such as neurotrophic factors, gene therapy constructs, or anti-inflammatory agents directly to target neural cells for conditions like Alzheimer's disease, Parkinson's disease, stroke recovery, multiple sclerosis, and even glioblastoma. Their biocompatibility and low immunogenicity further reduce systemic side effects, making them a safer alternative to synthetic delivery systems. This review outlines recent progress in extraction techniques using EVs for treating neurological disorders. It covers clinical applications in neurodegenerative, infectious diseases, inflammatory, genetic, and oncological diseases and highlights current limitations and considerations for advancing future research in this evolving field.