Loss of Sarm1 does not suppress motor neuron degeneration in the SOD1G93A mouse model of amyotrophic lateral sclerosis

Hum Mol Genet. 2018 Nov 1;27(21):3761-3771. doi: 10.1093/hmg/ddy260.

Abstract

Axon degeneration occurs in all neurodegenerative diseases, but the molecular pathways regulating axon destruction during neurodegeneration are poorly understood. Sterile Alpha and TIR Motif Containing 1 (Sarm1) is an essential component of the prodegenerative pathway driving axon degeneration after axotomy and represents an appealing target for therapeutic intervention in neurological conditions involving axon loss. Amyotrophic lateral sclerosis (ALS) is characterized by rapid, progressive motor neuron degeneration and muscle atrophy, causing paralysis and death. Patient tissue and animal models of ALS show destruction of upper and lower motor neuron cell bodies and loss of their associated axons. Here, we investigate whether loss of Sarm1 can mitigate motor neuron degeneration in the SOD1G93A mouse model of ALS. We found no change in survival, behavioral, electrophysiogical or histopathological outcomes in SOD1G93A mice null for Sarm1. Blocking Sarm1-mediated axon destruction alone is therefore not sufficient to suppress SOD1G93A-induced neurodegeneration. Our data suggest the molecular pathways driving axon loss in ALS may be Sarm1-independent or involve genetic pathways that act in a redundant fashion with Sarm1.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amyotrophic Lateral Sclerosis / metabolism*
  • Amyotrophic Lateral Sclerosis / pathology
  • Animals
  • Armadillo Domain Proteins / metabolism*
  • Armadillo Domain Proteins / physiology
  • Axotomy
  • Cytoskeletal Proteins / metabolism*
  • Cytoskeletal Proteins / physiology
  • Disease Models, Animal
  • Male
  • Mice
  • Mice, Transgenic
  • Motor Neurons / metabolism*
  • Nerve Degeneration*
  • Superoxide Dismutase / genetics

Substances

  • Armadillo Domain Proteins
  • Cytoskeletal Proteins
  • SARM1 protein, mouse
  • Superoxide Dismutase