Muscle satellite cells and fibro-adipogenic progenitors from muscle contractures of children with cerebral palsy have impaired regenerative capacity

In cerebral palsy (CP), muscles often develop contractures, where the muscle is shorter and stiffer than healthy muscle. This impairs muscle function, limiting the ability of children with CP to have full range of motion and function of their muscles.

Muscles are made up of millions of cells and several different cell types. One of these key cell types form new muscle when the muscle is injured or growing. Another cell type produces a network of proteins that provide support and structure to the muscle. The goal of this study was to understand how these two cell types change with contracture. This will allow us to identify changes in cell behavior in CP and therefore identify targets to improve muscle function.

To do so, we compared cells taken from muscle biopsies of six children with CP and six typically developing (TD) children. We found that cells from children with CP did not form muscle as much as TD cells. These cells also had worse muscle formation on stiffnesses that represent contractures compared to healthy-like stiffnesses. This indicates that when the muscle is injured in CP, it cannot recover as easily. We found that treatment with a drug called verteporfin slightly improved muscle formation. We also found that the cells that produce the proteins and structure in muscle change into a more diseased state in CP compared to TD.