Author:

Keywords:

Science & Technology, Life Sciences & Biomedicine, Neurosciences, Neurosciences & Neurology, Extracellular vesicles, Alzheimer's disease, Blood-cerebrospinal fluid barrier, Choroid plexus, Complement, TO-CELL TRANSMISSION, HUMAN CHOROID-PLEXUS, TRANSPORTER EXPRESSION, IMMUNE-COMPLEXES, INNATE IMMUNITY, COMPLEMENT C3, IN-VIVO, BRAIN, OLIGOMERS, EXOSOMES, Alzheimer’s disease, Blood–cerebrospinal fluid barrier, Alzheimer Disease, Amyloid beta-Peptides, Animals, Blood-Brain Barrier, Cells, Cultured, Choroid Plexus, Extracellular Vesicles, Female, Injections, Intraventricular, Mice, Mice, Inbred C57BL, Mice, Transgenic, 0601 Biochemistry and Cell Biology, 1103 Clinical Sciences, 1109 Neurosciences, 3101 Biochemistry and cell biology, 3209 Neurosciences

Abstract:

Increasing evidence indicates that extracellular vesicles (EVs) play an important role in the pathogenesis of Alzheimer's disease (AD). We previously reported that the blood-cerebrospinal fluid (CSF) interface, formed by the choroid plexus epithelial (CPE) cells, releases an increased amount of EVs into the CSF in response to peripheral inflammation. Here, we studied the importance of CP-mediated EV release in AD pathogenesis. We observed increased EV levels in the CSF of young transgenic APP/PS1 mice which correlated with high amyloid beta (Aβ) CSF levels at this age. The intracerebroventricular (icv) injection of Aβ oligomers (AβO) in wild-type mice revealed a significant increase of EVs in the CSF, signifying that the presence of CSF-AβO is sufficient to induce increased EV secretion. Using in vivo, in vitro and ex vivo approaches, we identified the CP as a major source of the CSF-EVs. Interestingly, AβO-induced, CP-derived EVs induced pro-inflammatory effects in mixed cortical cultures. Proteome analysis of these EVs revealed the presence of several pro-inflammatory proteins, including the complement protein C3. Strikingly, inhibition of EV production using GW4869 resulted in protection against acute AβO-induced cognitive decline. Further research into the underlying mechanisms of this EV secretion might open up novel therapeutic strategies to impact the pathogenesis and progression of AD.