Fibroblast to myofibroblast transition in the heart in response to cardiomyocyte injury, proinflammatory cytokines, and systemic inflammation through reactive oxygen species (ROS). Created with BioRender.com. Ang II, angiotensin II; Gal-3, galectin-3; MMP, matrix metalloprotinase; TGF-β, transforming growth factor-β; TIMP, tissue inhibitor of metalloprotinase; TNF-α, tumor necrosis factor-α.