Spatial transcriptomics reveal markers of histopathological changes in Duchenne muscular dystrophy mouse models

Abstract

Duchenne muscular dystrophy (DMD) is caused by mutations in the DMD gene, leading to lack of dystrophin. Chronic muscle damage eventually leads to histological alterations in skeletal muscles. The identification of genes and cell types driving tissue remodeling is a key step to develop effective therapies. Here we use spatial transcriptomics in two DMD mouse models differing in disease severity to identify gene expression signatures underlying skeletal muscle pathologies and directly link this to the muscle histology. Deconvolution analysis allowed the identification of cell types contributing to histological alterations. We show how the expression of specific genes is enriched in areas of muscle regeneration (Myl4, Sparc, Hspg2), fibrosis (Vim, Fn1, Thbs4) and calcification (Bgn, Ctsk, Spp1). Finally, our analysis of differentiation dynamics in the severely affected D2-mdx muscle shows a subset of the muscle fibers are predicted to become affected in its future state. Genes associated with tissue remodeling could enable to design new diagnostic and therapeutic strategies for DMD.