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Title: Mechanical injuries of neurons induce tau mislocalization to dendritic spines and tau-dependent synaptic dysfunction
Chronic traumatic encephalopathy (CTE) is associated with repeated traumatic brain injuries (TBI) and is characterized by cognitive decline and the presence of neurofibrillary tangles (NFTs) of the protein tau in patients’ brains. Here we provide direct evidence that cell-scale mechanical deformation can elicit tau abnormalities and synaptic deficits in neurons. Using computational modeling, we find that the early pathological loci of NFTs in CTE brains are regions of high deformation during injury. The mechanical energy associated with high-strain rate deformation alone can induce tau mislocalization to dendritic spines and synaptic deficits in cultured rat hippocampal neurons. These cellular changes are mediated by tau hyperphosphorylation and can be reversed through inhibition of GSK3β and CDK5 or genetic deletion of tau. Together, these findings identify a mechanistic pathway that directly relates mechanical deformation of neurons to tau-mediated synaptic impairments and provide a possibly exploitable therapeutic pathway to combat CTE.  more » « less
Award ID(s):
1935834
PAR ID:
10200249
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Proceedings of the National Academy of Sciences
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
117
Issue:
46
ISSN:
0027-8424
Page Range / eLocation ID:
p. 29069-29079
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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