Exosome therapy for facilitating stroke recovery

Abstract

Axonal regeneration plays a pivotal role in tissue repair and is compelling for functional recovery after stroke. On the other hand, several inhibitory molecules for axonal outgrowth exist in the central nervous system (CNS). In the peri–infarct area of the middle cerebral artery occlusion (MCAO) rat model, we identified that the axons and dendrites were regenerated in the chronic phase of stroke (2 months). In vitro, we showed that PTEN/Akt/GSK–3β signaling is involved in axonal outgrowth after stroke. Several studies documented that exosomes, intrinsic cell–derived membrane vesicles in the size range of 40–100 nm, enhanced tissue repair and functional recovery after stroke. Exosome treatment tends to have less tumorigenicity, does not occlude the microvascular system in CNS, and has low immunogenicity, as compared to conventional cell therapy. Recently, we found that anti–inflammatory regulation of post–stroke glial scars via MAPK/NF–κB/ TNF–α/Il–1β signaling, and treatment with miR–146a–5p facilitated stroke recovery in rat MCAO model. Thus, exosomes can be a therapeutic candidate of treatment for stroke recovery.