title: Micro-MRI study of cerebral aging: ex vivo detection of hippocampal subfield reorganization, microhemorrhages and amyloid plaques in mouse lemur primates.
abstract: Mouse lemurs are non-human primate models of cerebral aging and neurodegeneration. Much smaller than other primates, they recapitulate numerous features of human brain aging, including progressive cerebral atrophy and correlation between regional atrophy and cognitive impairments. Characterization of brain atrophy in mouse lemurs has been done by MRI measures of regional CSF volume and by MRI measures of regional atrophy. Here, we further characterize mouse lemur brain aging using ex vivo MR microscopy (31 µm in-plane resolution). First, we performed a non-biased, direct volumetric quantification of dentate gyrus and extended Ammon's horn. We show that both dentate gyrus and Ammon's horn undergo an age-related reorganization leading to a growth of the dentate gyrus and an atrophy of the Ammon's horn, even in the absence of global hippocampal atrophy. Second, on these first MR microscopic images of the mouse lemur brain, we depicted cortical and hippocampal hypointense spots. We demonstrated that their incidence increases with aging and that they correspond either to amyloid deposits or to cerebral microhemorrhages.
authors: CNRS (Centre National de la Recherche Scientifique), URA2210 (Unité de Recherche Autonome 2210), Fontenay-aux-Roses, France.
authors: Anne
authors: A
authors: Bertrand
authors: Adrien
authors: A
authors: Pasquier
authors: Alexandra
authors: A
authors: Petiet
authors: Christopher
authors: C
authors: Wiggins
authors: Audrey
authors: A
authors: Kraska
authors: Nelly
authors: N
authors: Joseph-Mathurin
authors: Fabienne
authors: F
authors: Aujard
authors: Nadine
authors: N
authors: Mestre-Francés
authors: Marc
authors: M
authors: Dhenain
mesh_terms: D000375:Aging / Q000473:pathology*; D000818:Animals; D002540:Cerebral Cortex / Q000473:pathology / Q000503:physiopathology; D016565:Cheirogaleidae / Q000502:physiology*; D006624:Hippocampus / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D020300:Intracranial Hemorrhages / Q000150:complications / Q000473:pathology / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D058225:Plaque, Amyloid / Q000150:complications / Q000473:pathology / Q000503:physiopathology*