Parathyroid hormone inhibits fatty infiltration and muscle atrophy after rotator cuff tear by fibro-adipogenic progenitors browning in a rodent model

Progressive fatty infiltration and muscle atrophy after rotator cuff tears increase the re-tear rate after rotator cuff repair. Fibro-adipogenic progenitors (FAP) are involved in fatty infiltration and skeletal muscle homeostasis. Inducing FAP to differentiate into brown adipocyte-like "beige adipocytes" inhibits fatty infiltration and muscle atrophy. In this study, we focused on the parathyroid hormone (PTH) as a potential drug. This study aimed to clarify whether PTH suppresses the progression of fatty infiltration and muscle atrophy after rotator cuff tears by browning FAP in a rat model.