Myotonic dystrophy type 1 (DM1) is the most common myopathy in adults. Symptoms of the patients are mainly characterized by muscle weakness, atrophy, and myotonia. These features can be partially explained by an altered function of muscle stem cells (MuSCs) responsible for muscle development (myogenesis process) and the presence of defective MuSCs with an abnormal inflammatory profile. Small molecules derived from omega-3 fatty acids play an active role in the resolution of inflammation. These bioactive lipids significantly decrease in vitro the inflammation genes expression in MuSCs of DM1 patients and partially restore MuSC function. Thus, aim of our study is to validate in vivo their impact on inflammation, myogenesis and muscle regeneration. We will use the DMSXL transgenic mice as a model of DM1. These mice will be treated with different bioactive lipids or placebo. Their muscle strength will be assessed and muscles sections will be used to perform immunostaining to evaluate senescence and myogenesis. The treatment effect on inflammation will be measured by Multiplex in muscle and serum. This project is an essential pre-clinical step leading to the validation of drugs in order to improve patient care and their quality of life.