title: Evidence for early cognitive impairment related to frontal cortex in the 5XFAD mouse model of Alzheimer's disease.
abstract: The frontal cortex is a brain structure that plays an important role in cognition and is known to be affected in Alzheimer's disease (AD) in humans. Over the past years, transgenic mouse models have been generated to recapitulate the main features of this disease, including cognitive impairments. This study investigates frontal cortex dependent learning abilities in one of the most early-onset transgenic murine model of AD, the 5XFAD mice. We compared frontal performance of 2-, 4-, and 6-month-old 5XFAD mice with their wild-type littermates using a newly developed automated device, the olfactory H-maze, in which mice have to discover three different rules consecutively according to the delayed reaction paradigm. We report early cognitive deficits related to frontal cortex appearing in 4-month-old 5XFAD mice before hippocampal-dependent learning and memory impairment, in relation with neuropathologic processes such as strong gliosis and emerging amyloid plaques. The present results demonstrate that the olfactory H-maze is a very sensitive and simple experimental paradigm that allows assessment of frontal functions in transgenic mice and should be useful to test pre-clinical therapeutic approaches to alter the course of AD.
authors.affiliation: Aix-Marseille University, CNRS, NICN, UMR7259, Marseille, France.
authors.forename: Stéphane D
authors.initials: SD
authors.lastname: Girard
authors.forename: Kévin
authors.initials: K
authors.lastname: Baranger
authors.forename: Cyrielle
authors.initials: C
authors.lastname: Gauthier
authors.forename: Marlyse
authors.initials: M
authors.lastname: Jacquet
authors.forename: Anne
authors.initials: A
authors.lastname: Bernard
authors.forename: Guy
authors.initials: G
authors.lastname: Escoffier
authors.forename: Evelyne
authors.initials: E
authors.lastname: Marchetti
authors.forename: Michel
authors.initials: M
authors.lastname: Khrestchatisky
authors.forename: Santiago
authors.initials: S
authors.lastname: Rivera
authors.forename: François S
authors.initials: FS
authors.lastname: Roman
mesh_terms: D000367:Age Factors; D000544:Alzheimer Disease / Q000150:complications / Q000235:genetics / Q000473:pathology; D016564:Amyloid beta-Protein Precursor / Q000235:genetics; D000704:Analysis of Variance; D000818:Animals; D060825:Cognitive Dysfunction / Q000175:diagnosis* / Q000209:etiology* / Q000235:genetics; D005625:Frontal Lobe / Q000378:metabolism / Q000473:pathology*; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006801:Humans; D008279:Magnetic Resonance Imaging; D018782:Maze Learning / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009154:Mutation / Q000235:genetics; D000857:Olfaction Disorders / Q000209:etiology* / Q000235:genetics; D053764:Presenilin-1 / Q000235:genetics; D011930:Reaction Time / Q000235:genetics
chemical_list: D016564:Amyloid beta-Protein Precursor; D005904:Glial Fibrillary Acidic Protein; C508853:PSEN1 protein, human; D053764:Presenilin-1