SARM1 Inhibition in Three Mouse Models of Charcot-Marie-Tooth Disease.
Document Type
Article
Publication Date
9-1-2025
Original Citation
Rice A,
Tadenev A,
Hines T,
Funke J,
Burgess RW.
SARM1 Inhibition in Three Mouse Models of Charcot-Marie-Tooth Disease. J Peripher Nerv Syst. 2025;30(3):e70053.
Keywords
JMG, Animals, Charcot-Marie-Tooth Disease, Armadillo Domain Proteins, Cytoskeletal Proteins, Mice, Disease Models, Animal, Mice, Transgenic, Mice, Inbred C57BL, Axons
JAX Source
J Peripher Nerv Syst. 2025;30(3):e70053.
ISSN
1529-8027
PMID
40833344
DOI
https://doi.org/10.1111/jns.70053
Grant
The Scientific Services are supported by NIH grant CA34196. This work was funded by NIH grants R37NS054154 and R03NS123787 to R.W.B. and K99NS130151 to T.J.H.
Abstract
BACKGROUND: Charcot-Marie-Tooth (CMT) disease can be caused by mutations in over 100 different genes, most of which lead to demyelination (type 1) or degeneration (type 2) of peripheral motor and sensory axons. SARM1 is a protein involved in the active process of Wallerian degeneration after axonal injury. Inhibition of SARM1 protects against axon degeneration following injury or in cases such as chemotherapy-induced peripheral neuropathy. However, the effects of SARM1 inhibition on axon degeneration in genetic diseases such as CMT are less clear.
AIMS: Here we tested whether SARM1 inhibition may be of benefit in three different mouse models of axonal CMT: Gars
METHODS: For these proof-of-concept studies, mice were treated as neonates with an AAV9 to deliver a dominant negative SARM1 construct (dnSARM1) to the nervous system by intracerebroventricular injection. At ages appropriate for each mouse model, animals were then evaluated with a combination of behavioral, neurophysiological, and histological outcomes.
RESULTS: We reproduced the protective effects of the dnSARM1 construct in positive control experiments following sciatic nerve crush. However, we did not see a change in the phenotypes of any of the CMT mouse models examined. The neuropathy-related phenotypes neither worsened nor improved. Wild-type littermate controls treated with the AAV9 dnSARM1 had minor reductions in body weight and variable changes in motor performance compared to untreated controls, but no deficits by neurophysiology or histology.
INTERPRETATION: Inhibiting SARM1 using a virally delivered dominant negative construct was not efficacious in any of the three mouse models of CMT we tested. These mouse models were chosen for their relevance to the human disease and their prominent axon degeneration, and not for metabolic changes that would suggest SARM1 as a therapeutic target. SARM1 inhibition may remain an option for some forms of CMT, but a method for prescreening CMT subtypes to predict efficacy is needed.