Amyotrophic lateral sclerosis and skeletal muscle: an update

Area of Science:

• Neuroscience
• Muscle Biology
• Genetics

Background:

• Amyotrophic lateral sclerosis (ALS) is a motor neuron disease causing weakness and atrophy.
• The traditional view focused on motor neuron degeneration, with muscle changes as secondary.
• Emerging evidence implicates non-neuronal cells, including skeletal muscle fibers, in ALS pathogenesis.

Purpose of the Study:

• To review recent findings on skeletal muscle fiber alterations in ALS.
• To explore the relationship between mutant SOD1 and skeletal muscle changes.
• To analyze functional, molecular, and cellular changes within ALS skeletal muscle.

Main Methods:

• Literature review of recent studies on ALS and skeletal muscle.
• Analysis of evidence linking mutant SOD1 to muscle pathology.
• Examination of data on muscle function, gene expression, mitochondrial health, protein aggregation, and proteasome activity.

Main Results:

• Skeletal muscle fibers are actively involved in ALS, not just passively affected by motor neuron loss.
• Mutant SOD1 has a significant impact on skeletal muscle, contributing to disease progression.
• ALS skeletal muscle exhibits altered function, myogenic regulatory factor expression, mitochondrial dysfunction, SOD1 aggregation, and proteasome impairment.

Conclusions:

• The neurocentric view of ALS is incomplete; skeletal muscle is a key player.
• Interactions between motor neurons and skeletal muscle contribute to ALS pathology.
• Targeting skeletal muscle alterations may offer new therapeutic strategies for ALS.