Genetic ablation of Sarm1 attenuates expression and mislocalization of phosphorylated TDP-43 after mouse repetitive traumatic brain injury

© 2023. The Author(s)..

Traumatic brain injury (TBI), particularly when moderate-to-severe and repetitive, is a strong environmental risk factor for several progressive neurodegenerative disorders. Mislocalization and deposition of transactive response DNA binding protein 43 (TDP-43) has been reported in both TBI and TBI-associated neurodegenerative diseases. It has been hypothesized that axonal pathology, an early event after TBI, may promote TDP-43 dysregulation and serve as a trigger for neurodegenerative processes. We sought to determine whether blocking the prodegenerative Sarm1 (sterile alpha and TIR motif containing 1) axon death pathway attenuates TDP-43 pathology after TBI. We subjected 111 male Sarm1 wild type, hemizygous, and knockout mice to moderate-to-severe repetitive TBI (rTBI) using a previously established injury paradigm. We conducted serial neurological assessments followed by histological analyses (NeuN, MBP, Iba-1, GFAP, pTDP-43, and AT8) at 1 month after rTBI. Genetic ablation of the Sarm1 gene attenuated the expression and mislocalization of phosphorylated TDP-43 (pTDP-43) and accumulation of pTau. In addition, Sarm1 knockout mice had significantly improved cortical neuronal and axonal integrity, functional deficits, and improved overall survival after rTBI. In contrast, removal of one Sarm1 allele delayed, but did not prevent, neurological deficits and neuroaxonal loss. Nevertheless, Sarm1 haploinsufficient mice showed significantly less microgliosis, pTDP-43 pathology, and pTau accumulation when compared to wild type mice. These data indicate that the Sarm1-mediated prodegenerative pathway contributes to pathogenesis in rTBI including the pathological accumulation of pTDP-43. This suggests that anti-Sarm1 therapeutics are a viable approach for preserving neurological function after moderate-to-severe rTBI.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:11

Enthalten in:

Acta neuropathologica communications - 11(2023), 1 vom: 20. Dez., Seite 206

Sprache:

Englisch

Beteiligte Personen:

Dogan, Elif O [VerfasserIn]
Bouley, James [VerfasserIn]
Zhong, Jianjun [VerfasserIn]
Harkins, Ashley L [VerfasserIn]
Keeler, Allison M [VerfasserIn]
Bosco, Daryl A [VerfasserIn]
Brown, Robert H [VerfasserIn]
Henninger, Nils [VerfasserIn]

Links:

Volltext

Themen:

Axon
Behavior
Brain injury
DNA-Binding Proteins
Glial scar
Haploinsufficiency
Interleukin
Journal Article
Neurodegeneration
SARM1
SARM1 protein, mouse
TDP-43
Tardbp protein, mouse
Tau

Anmerkungen:

Date Completed 02.01.2024

Date Revised 10.02.2024

published: Electronic

Citation Status MEDLINE

doi:

10.1186/s40478-023-01709-4

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM366148044