Specialized proteins that help gene expression, aka transcription factors, MyoD and Myf5 activate to prepare for cell fusion.
MyoDMyf5
Undoing the Damage: Anti-inflammatory responseNegative feedback systemStimulus : Cytokines released by M1 MacrophagesSensor: Nerve cells in the skin & brainControl : White blood cells (Monocytes)Organ systems involved : lymphatic, musculoskeletal, nervous systemEffector: M2 Macrophages
M2 macrophages activate and counter inflammation created by M1 macrophages. The M1 macrophage population declines.
M2
Undoing the Damage: Repairing Muscle FibreNegative feedback systemStimulus : M2 MacrophageSensor: Nerve cells in the skin & brainOrgan systems involved : lymphatic, musculoskeletal, nervous systemControl: Satellite CellsEffector: Satellite Cells
M2 macrophages trigger differentiation of Satellite cells into specialized daughter cells called myoblasts.
M2
Myoblasts fuse with other myoblasts and/or damaged muscle fibre to reconstruct damaged muscle tissue.