McGowan Institute researchers have successfully used gene therapy to accelerate muscle regeneration in experimental animals with muscle damage, suggesting this technique may be a novel and effective approach for improving skeletal muscle healing, particularly for serious sports-related injuries.
Skeletal muscle injuries are the most common injuries encountered in sports medicine. Although such injuries can heal on their own, the formation of scar tissue may prevent a complete recovery of function. Of particular concern are top athletes who, when injured, need to recover fully as quickly as possible.
In this study, the researchers injected mice with a gene therapy vector containing myostatin propeptide – a protein that blocks the activity of the muscle-growth inhibitor myostatin – three weeks prior to experimentally damaging the mice's skeletal muscles. Four weeks after skeletal muscle injury, the investigators observed better muscle regeneration in the gene-therapy treated mice compared to untreated control mice. There also was significantly less fibrous scar tissue in the skeletal muscle of the gene-therapy treated mice compared to the control mice.
Corresponding author Johnny Huard, the Henry J. Mankin Endowed Chair and Professor in Orthopaedic Surgery, School of Medicine, and director of the Stem Cell Research Center of Children's Hospital, said this approach offers a significant, long-lasting method for treating serious, sports-related muscle injuries.
"Based on our previous studies, we expect that gene-therapy treated cells will continue to overproduce myostatin propeptide for at least two years. Since the remodeling phase of skeletal muscle healing is a long-term process, we believe that prolonged expression of myostatin propeptide will continue to contribute to recovery of injured skeletal muscle by inducing an increase in muscle mass and minimizing fibrosis. This could significantly reduce the amount of time an athlete needs to recover and result in a more complete recovery," he explained.
Others involved in the study included Jinhong Zhu and Yong Li of the Growth and Development Laboratory, Children's Hospital; and Chunping Qiao and Xiao Xiao of the Molecular Therapies Laboratory, Department of Orthopaedic Surgery, School of Medicine.