Description:Neurotransmitter release occurs through exocytosis of synaptic vesicles. α-Synuclein’s function and dysfunction in Parkinson’s disease and other synucleinopathies is tightly linked to synaptic vesicle binding. Age is the biggest risk factor for synucleinopathy, yet, age- and disease-induced changes in synaptic vesicles remain unexplored. Systematic analysis of the synaptic vesicle lipidome revealed specific changes in two mouse models of synucleinopathy over age. Strikingly, changes in mice lacking α-synuclein were more pronounced than changes in a humanized α-synucleinopathy mouse model, suggesting that loss of α-synuclein function is a major contributor to synaptic dysfunction. These findings not only provide new insights into synaptic vesicle biology and mechanisms of synucleinopathy, but also offer a baseline for further mechanistic exploration of age- and disease-related alterations in synaptic vesicles.