The Effects of An Extracellular Matrix Hydrogel on Muscle Pathology and Regeneration in Dystrophic Skeletal Muscle
In Duchenne muscular dystrophy (DMD), the lack of dystrophin leads to sarcolemma instability, which causes muscle to become fragile and waste over time. Biological scaffolds made of extracellular matrix (ECM) have been used in other disease models to promote tissue repair. This study investigates the effect of injecting porcine-derived ECM hydrogel on muscle pathology and regeneration in mdx mice, the murine model of DMD. We analyze common features of dystrophy including central nucleation, variable fiber cross-sectional area, and fibrosis. Previous work in our lab suggests that the failed regeneration observed in DMD is a result of inefficient cell adhesion and stem cell function caused by fibrotic ECM. Therefore, we examined cell adhesion by quantifying adhesion proteins laminin, utrophin, and dystroglycan. Because inflammation is also a barrier to stem cell function and biological scaffolds are known to polarize macrophage phenotypes, we also quantified macrophage markers to determine macrophage phenotype.