PHYS30005 Lecture 27: Lecture 27 – Muscle regeneration

• School: University of Melbourne
• Department: Physiology
• Course: PHYS30005
• Professor: Charles Sevigny

Document Summary

Sequestial cycle of muscle healing phases after laceration. An inflammatory response commitment of phagocytic inflammatory cells, critical for initiating muscle fibre repair. Localised neutrophils release degradative enzymes, destroy debris, increase vascular permeability as well as stimulating monocyte accumulation and satellite cells. Accumulated macrophages phagocytise debris and neutrophils, release factors that activate and stimulate satellite cells. Inflammation: affected by viability of local vasculature, macrophage derived factors stimulate satellite cells. Inflammatory response is critical for muscle fibre regeneration (for activation of muscle stem cells) Inflammatory signature compromised in magnitude and/or duration: too little inflammation, too much inflammation, too brief or too long all interfere with optimal regeneration. Changes in macrophage phenotype and stages of myogenesis in regenerative muscle after injury. During initial stages of inflammation, pax7+ satellite cells are activated, proliferate and begin expression of myod, initiating transcription of muscle-specific genes necessary for early differentiation.