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Amyloid-β Oligomers Induce Only Mild Changes to Inhibitory Bouton Dynamics.

ABSTRACT: The amyloid-β protein precursor is highly expressed in a subset of inhibitory neuron in the hippocampus, and inhibitory neurons have been suggested to play an important role in early Alzheimer's disease plaque load. Here we investigated bouton dynamics in axons of hippocampal interneurons in two independent amyloidosis models. Short-term (24 h) amyloid-β (Aβ)-oligomer application to organotypic hippocampal slices slightly increased inhibitory bouton dynamics, but bouton density and dynamics were unchanged in hippocampus slices of young-adult App ^{NL - F - G} -mice, in which Aβ levels are chronically elevated. These results indicate that loss or defective adaptation of inhibitory synapses are not a major contribution to Aβ-induced hyperexcitability.

SUBMITTER: Ruiter M

PROVIDER: S-EPMC8075564 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Amyloid-β Oligomers Induce Only Mild Changes to Inhibitory Bouton Dynamics.

Ruiter Marvin M Lützkendorf Christine C Liang Jian J Wierenga Corette J CJ

Journal of Alzheimer's disease reports 20210227 1

The amyloid-β protein precursor is highly expressed in a subset of inhibitory neuron in the hippocampus, and inhibitory neurons have been suggested to play an important role in early Alzheimer's disease plaque load. Here we investigated bouton dynamics in axons of hippocampal interneurons in two independent amyloidosis models. Short-term (24 h) amyloid-β (Aβ)-oligomer application to organotypic hippocampal slices slightly increased inhibitory bouton dynamics, but bouton density and dynamics were ...[more]

PMID: 33981952

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