Neurofilament accumulations in amyotrophic lateral sclerosis patients' motor neurons impair axonal initial segment integrity

© 2023. The Author(s)..

Amyotrophic lateral sclerosis (ALS) is the most common motor neuron (MN) disease in adults with no curative treatment. Neurofilament (NF) level in patient' fluids have recently emerged as the prime biomarker of ALS disease progression, while NF accumulation in MNs of patients is the oldest and one of the best pathological hallmarks. However, the way NF accumulations could lead to MN degeneration remains unknown. To assess NF accumulations and study the impact on MNs, we compared MNs derived from induced pluripotent stem cells (iPSC) of patients carrying mutations in C9orf72, SOD1 and TARDBP genes, the three main ALS genetic causes. We show that in all mutant MNs, light NF (NF-L) chains rapidly accumulate in MN soma, while the phosphorylated heavy/medium NF (pNF-M/H) chains pile up in axonal proximal regions of only C9orf72 and SOD1 MNs. Excitability abnormalities were also only observed in these latter MNs. We demonstrate that the integrity of the MN axonal initial segment (AIS), the region of action potential initiation and responsible for maintaining axonal integrity, is impaired in the presence of pNF-M/H accumulations in C9orf72 and SOD1 MNs. We establish a strong correlation between these pNF-M/H accumulations, an AIS distal shift, increased axonal calibers and modified repartition of sodium channels. The results expand our understanding of how NF accumulation could dysregulate components of the axonal cytoskeleton and disrupt MN homeostasis. With recent cumulative evidence that AIS alterations are implicated in different brain diseases, preserving AIS integrity could have important therapeutic implications for ALS.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:80

Enthalten in:

Cellular and molecular life sciences : CMLS - 80(2023), 6 vom: 15. Mai, Seite 150

Sprache:

Englisch

Beteiligte Personen:

Lefebvre-Omar, Cynthia [VerfasserIn]
Liu, Elise [VerfasserIn]
Dalle, Carine [VerfasserIn]
d'Incamps, Boris Lamotte [VerfasserIn]
Bigou, Stéphanie [VerfasserIn]
Daube, Clément [VerfasserIn]
Karpf, Léa [VerfasserIn]
Davenne, Marc [VerfasserIn]
Robil, Noémie [VerfasserIn]
Jost Mousseau, Coline [VerfasserIn]
Blanchard, Stéphane [VerfasserIn]
Tournaire, Guillaume [VerfasserIn]
Nicaise, Charles [VerfasserIn]
Salachas, François [VerfasserIn]
Lacomblez, Lucette [VerfasserIn]
Seilhean, Danielle [VerfasserIn]
Lobsiger, Christian S [VerfasserIn]
Millecamps, Stéphanie [VerfasserIn]
Boillée, Séverine [VerfasserIn]
Bohl, Delphine [VerfasserIn]

Links:

Volltext

Themen:

Amyotrophic lateral sclerosis
Axonal initial segment
C9orf72 Protein
Degeneration
EC 1.15.1.1
Human induced pluripotent stem cells
Journal Article
Motoneurons
Neurofilaments
Superoxide Dismutase-1

Anmerkungen:

Date Completed 17.05.2023

Date Revised 19.06.2023

published: Electronic

Citation Status MEDLINE

doi:

10.1007/s00018-023-04797-6

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM356873064