doi:10.1021/jacs.5b13577engPedersen, J.T.Chen, S.W.Borg, C.B.Ness, S.Bahl, J.M.Heegaard, N.H.H.Dobson, C.M.Hemmingsen, L.Cremades, N.Teilum, K.Amyloid-ß and a-Synuclein Decrease the Level of Metal-Catalyzed Reactive Oxygen Species by Radical Scavenging and Redox SilencingART-2016-95015The formation of reactive oxygen species (ROS) is linked to the pathogenesis of neurodegenerative diseases. Here we have investigated the effect of soluble and aggregated amyloid-ß (Aß) and a-synuclein (aS), associated with Alzheimer''s and Parkinson''s diseases, respectively, on the Cu2+-catalyzed formation of ROS in vitro in the presence of a biological reductant. We find that the levels of ROS, and the rate by which ROS is generated, are significantly reduced when Cu2+ is bound to Aß or aS, particularly when they are in their oligomeric or fibrillar forms. This effect is attributed to a combination of radical scavenging and redox silencing mechanisms. Our findings suggest that the increase in ROS associated with the accumulation of aggregated Aß or aS does not result from a particularly ROS-active form of these peptides, but rather from either a local increase of Cu2+ and other ROS-active metal ions in the aggregates or as a downstream consequence of the formation of the pathological amyloid structures.2016http://zaguan.unizar.es/record/5606710.1021/jacs.5b13577http://zaguan.unizar.es/record/56067oai:zaguan.unizar.es:56067JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 138, 12 (2016), 3966-3969byhttp://creativecommons.org/licenses/by/3.0/es/info:eu-repo/semantics/openAccess