Muscle fiber degeneration occurs through a series of stages:
1. Initial Damage: Muscle fibers can be damaged by mechanical stress, inflammation, or genetic defects. This initial injury triggers a cascade of cellular events. 2. Inflammatory Response: The damaged muscle fibers release cytokines and other signaling molecules, attracting immune cells such as macrophages and neutrophils. 3. Proteolytic Pathways: Activated proteolytic enzymes, including calpains and caspases, degrade the structural proteins of muscle fibers. 4. Necrosis and Apoptosis: Muscle fibers may undergo necrosis or apoptosis, leading to the removal of dead or dying cells by phagocytosis. 5. Fibrosis: In chronic conditions, fibrous connective tissue may replace degenerated muscle fibers, impairing muscle function.
