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Spatial learning and memory impairments are associated with increased neuronal activity in 5XFAD mouse as measured by manganese-enhanced magnetic resonance imaging.

ABSTRACT: Dysfunction of neuronal activity is a major and early contributor to cognitive impairment in Alzheimer's disease (AD). To investigate neuronal activity alterations at early stage of AD, we encompassed behavioral testing and in vivo manganese-enhanced magnetic resonance imaging (MEMRI) in 5XFAD mice at early ages (1-, 2-, 3- and 5-month). The 5XFAD model over-express human amyloid precursor protein (APP) and presenilin 1 (PS1) harboring five familial AD mutations, which have a high APP expression correlating with a high burden and an accelerated accumulation of the 42 amino acid species of amyloid-?. In the Morris water maze, 5XFAD mice showed longer escape latency and poorer memory retention. In the MEMRI, 5XFAD mice showed increased signal intensity in the brain regions involved in spatial cognition, including the entorhinal cortex, the hippocampus, the retrosplenial cortex and the caudate putamen. Of note, the observed alterations in spatial cognition were associated with increased MEMRI signal intensity. These findings indicate that aberrant increased basal neuronal activity may contribute to the spatial cognitive function impairment at early stage of AD, and may further suggest the potential use of MEMRI to predict cognitive impairments. Early intervention that targets aberrant neuronal activity may be crucial to prevent cognitive impairment.

SUBMITTER: Tang X

PROVIDER: S-EPMC5295372 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Spatial learning and memory impairments are associated with increased neuronal activity in 5XFAD mouse as measured by manganese-enhanced magnetic resonance imaging.

Tang Xiang X Wu Di D Gu Li-Hua LH Nie Bin-Bin BB Qi Xin-Yang XY Wang Yan-Juan YJ Wu Fang-Fang FF Li Xiao-Li XL Bai Feng F Chen Xiao-Chun XC Xu Lin L Ren Qing-Guo QG Zhang Zhi-Jun ZJ

Oncotarget 20160901 36

Dysfunction of neuronal activity is a major and early contributor to cognitive impairment in Alzheimer's disease (AD). To investigate neuronal activity alterations at early stage of AD, we encompassed behavioral testing and in vivo manganese-enhanced magnetic resonance imaging (MEMRI) in 5XFAD mice at early ages (1-, 2-, 3- and 5-month). The 5XFAD model over-express human amyloid precursor protein (APP) and presenilin 1 (PS1) harboring five familial AD mutations, which have a high APP expression ...[more]

PMID: 27542275

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Spatial learning and memory impairments are associated with increased neuronal activity in 5XFAD mouse as measured by manganese-enhanced magnetic resonance imaging.

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Spatial learning and memory impairments are associated with increased neuronal activity in 5XFAD mouse as measured by manganese-enhanced magnetic resonance imaging.

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