S resulting from synaptic dysfunction and HDAC1 Purity & Documentation protect against the spread of oligomer-induced pathology for the duration of illness progression. Our goal was to identify anti–synuclein oligomer drug candidates by screening compounds for the ability to rescue -synuclein oligomer-induced deficits in the target population: main neurons. We IKKε MedChemExpress identified recombinant full-length -synuclein protein oligomer preparations suitable for screening compound libraries that replicate the toxic effects of Parkinson’s patient brain-derived oligomers, applying assays that measure two key elements of cellular function identified to become disrupted by -synuclein oligomers: intracellular lipid vesicle trafficking (Izzo, Staniszewski, et al., 2014) and chaperone-mediated autophagy. Treatment of mature main hippocampal/cortical neuronal and glial cultures (21 days in vitro; DIV) with recombinant -synuclein oligomers also as -synuclein oligomer species isolated from brain samples from individuals with PD, but not non-PD agematched handle men and women, resulted in lipid vesicle trafficking deficits. Remedy of neuronal cultures with recombinant -synuclein oligomers also upregulated the expression of lysosomal-associated membrane protein-2A (LAMP-2A), a protein critically necessary for chaperone-mediated autophagy. This is the first report demonstrating that recombinant -synuclein oligomers possess a similar functional impact as PD patient brain-derived -synuclein oligomers. We then screened many libraries of smaller molecule compounds, including the NIH Clinical Collection to determine compounds capable of blocking recombinant -synuclein oligomer-induced lipid vesicle trafficking deficits. Unexpectedly, the most helpful compounds had been selective sigma-2 receptor allosteric antagonists, which blocked these deficits within a dose-dependent manner. These compounds also blocked recombinant -synuclein oligomer-induced LAMP-2A upregulation. Molecular interactions amongst sigma-2 receptor component proteins progesterone receptor membrane element 1(PGRMC1) and transmembrane protein 97 (TMEM97), -synuclein, and proteins that control vesicular tracking and autophagy (such as LC3B) may type the basis for these observations. Importantly, and for the first time, these data indicate that little molecule selective sigma-2 receptor complicated antagonists can influence a important modulator within the -synuclein signalingSignificanceOligomeric -synuclein proteins located in Parkinson’s illness patient brain tissue lead to neuron dysfunction, and therapeutic approaches correctly targeting them are urgently needed. For the very first time, this study demonstrates that recombinant and Parkinson’s patient-derived -synuclein bring about equivalent lipid vesicle trafficking deficits in neurons, when -synuclein species isolated from non-Parkinson’s human control brain samples do not. -Synuclein oligomers also upregulate lysosomal-associated membrane protein-2A (LAMP-2A), a protein essential to chaperonemediated autophagy. A broad search of current drug candidates revealed that antagonists in the sigma-2 receptor complicated have been the most helpful at blocking -synuclein oligomer-induced trafficking deficits and LAMP-2A upregulation. These drug candidates could represent a novel therapeutic method against Parkinson’s neuronal dysfunction and neurodegenerative problems brought on by -synuclein oligomer-mediated toxicity.LIMEGROVER Et aL.|cascade and cease oligomer-induced deficits. Inhibitors that modulate sigma-2 receptors may be therapeutic against ol.