Neuropeptide Y (NPY) prevents depressive-like behavior, spatial memory deficits and oxidative stress following amyloid-β (Aβ1-40) administration in mice

Neuropeptide Y (NPY) is a 36-amino acid peptide widely distributed in the central nervous system (CNS) that has been associated with the modulation of several functions including food intake, learning and memory, mood and neuroprotection. There is great interest in understanding the role of NPY in the deleterious effects induced by the central accumulation of amyloid-beta (A beta) peptides, a pathological hallmark of Alzheimer's disease (AD). Herein, we evaluated the effects of a single intracerebroventricular (i.c.v.) administration of NPY (0.0234 mu mol/mu L) 15 min prior to the i.c.v. injection of aggregated A beta(1-40) peptide (400 pmol/mouse) in behavioral and neurochemical parameters related to oxidative stress in mice. Pretreatment with NPY prevented A beta(1-40)-induced depressive-like responses and spatial memory impairments evaluated in the tail suspension and object location tasks, respectively. The protective effects of NPY on spatial memory of A beta(1-40)-treated mice were abolished by the pretreatment with the selective Y2 receptor antagonist BIIE0246. On the other hand, the administration of NPY and A beta(1-40) did not alter the performance of the animals in the elevated plus-maze and open field arena, indicating lack of effects on anxiety state and locomotor function. Although A beta(1-40) infusion did not change hippocampal and cortical glutathione peroxidase (GPx) activity and glutathione (GSH) levels, A beta(1-40)-infused animals showed an increased lipid peroxidation in hippocampus and prefrontal cortex that were blunted by NPY administration. These findings indicate that central administration of NPY prevents A beta(1-40)-induced depressive-like behavior and spatial memory deficits in mice and that this response is mediated, at least in part, by the activation of Y2 receptors and prevention of oxidative stress. (C) 2013 Elsevier B.V. All rights reserved.