High resolution three‐dimensional reconstruction of fibrotic skeletal muscle extracellular matrix

Abstract

Fibrosis occurs secondary to many skeletal muscle diseases and injuries, and can alter muscle function. It is unknown how collagen, the most abundant extracellular structural protein, alters its organization during fibrosis. Quantitative and qualitative high‐magnification electron microscopy shows that collagen is organized into perimysial cables which increase in number in a model of fibrosis, and cables have unique interactions with collagen‐producing cells. Fibrotic muscles are stiffer and have a higher concentration of collagen‐producing cells. These results improve our understanding of the organization of fibrotic skeletal muscle extracellular matrix and identify novel structures that might be targeted by antifibrotic therapy.