Lysosomal proteolysis in skeletal muscle

Area of Science:

• Muscle physiology and pathology
• Cellular biology
• Proteolytic systems

Background:

• Lysosomal proteases are abundant in fetal muscles but scarce in adult skeletal muscles.
• The lysosomal proteolytic system is activated in adult muscles during various pathological states.
• Recent studies highlight the presence of autophagosomes in muscle fibers and link excessive autophagy to myopathies.

Purpose of the Study:

• To review current knowledge of the lysosomal proteolytic system.
• To summarize evidence on the roles of lysosomes and autophagosomes in muscle physiology.
• To discuss the involvement of these systems in muscle pathology.

Main Methods:

• Literature review
• Synthesis of existing research
• Analysis of evidence on lysosomal and autophagic pathways in muscle.

Main Results:

• Lysosomal proteases show differential expression between fetal and adult skeletal muscle.
• Pathological conditions stimulate the lysosomal proteolytic system in adult muscles.
• Autophagosomes are present in muscle fibers, and excessive autophagy is associated with myopathies.

Conclusions:

• Lysosomes and autophagosomes play critical roles in both muscle physiology and pathology.
• Understanding these systems is crucial for investigating muscle diseases.
• Further research into the lysosomal proteolytic system and autophagy in muscle is warranted.