SLC1A2 and Parkinson disease: Human RBCEVs carrying α-synuclein isolated from patients with Parkinson's disease can cross the blood–brain barrier and impair glutamate uptake via an interaction between excitatory amino acid transporter 2 and oligomeric α-synuclein at astrocytic endfeet, leading to reduced synaptophysin levels in the striatum in a mouse model (158).