Mitochondria Isolated From Bone Mesenchymal Stem Cells Restrain Muscle Disuse Atrophy and Fatty Infiltration After Rotator Cuff Tears.

This article investigates the therapeutic potential of mitochondria isolated from bone mesenchymal stem cells (BMSC-Mito) in mitigating muscle degeneration following rotator cuff tears (RCTs) in a rat model. The study demonstrates that intramuscular injection of BMSC-Mito into the supraspinatus muscle after RCT significantly reduces muscle atrophy, fibrosis, and fatty infiltration, while preserving muscle mass, fiber type composition, and biomechanical properties. BMSC-Mito treatment also enhances mitochondrial function, reduces oxidative stress, and promotes angiogenesis by increasing vascular markers (CD31 and α-SMA). In vitro experiments further show that BMSC-Mito improve skeletal muscle cell viability and mitochondrial integrity under induced mitochondrial dysfunction. These findings suggest that BMSC-Mito may offer a promising approach to prevent rotator cuff muscle degeneration by protecting mitochondrial health and supporting muscle regeneration.