SLC1A2 and Parkinson disease: In support of these previous studies, oligomeric a-syn from erythrocyte-derived extracellular vesicles of PD patients has been shown to co-localize with GLT-1 in astrocytes and is associated with a reduction in glutamate clearance, possibly due to the inhibition of GLT1 function [170].These findings together suggest that a-syn accumulation in astrocytes can significantly alter glutamate neurotransmission in the brain, which has important implications for neurodegeneration.