Injury is a risk for all athletes and can seriously jeopardize the ability to continue play. Even for non-professional athletes whose careers are not necessarily jeopardized by injury, skeletal muscle injuries can diminish the quality of life. Those with skeletal muscle injuries may participate less in recreational sports and exercise less, hindering both psychological well-being and physical health. Finding ways for athletes to overcome these obstacles is critical.
Skeletal muscle injuries can occur in a variety of ways, including direct injury and over-exertion and may involve one or a combination of strain, laceration, or contusion. This type of injury is extremely common, and represents more than 35% of sports-related injuries. Athletes who endure these injuries can suffer from pain and muscle atrophy and are at increased risk for recurrent injuries. These athletes are also often subject to long recovery periods, which come with personal and professional costs.
Though there are medical interventions for skeletal muscle injury, each of these interventions suffers significant limitations. Surgery for instance, involves risks and long recovery periods, and pharmaceutical drugs are plagued by issues with effectiveness and side effects. While rest is often warranted following skeletal muscle injury, it is often not adequate for skeletal muscle recovery.
Stem cells represent an innovative way to help with skeletal muscle injury. By transplanting stem cells into the injured tissue, stem cells may be able to regenerate the tissue so that it functions normally without the need for other surgical or pharmacological interventions. The first promising results related to stem cell use in skeletal muscle injury have been seen with Duchenne muscular dystrophy (DMD). In DMD, a protein called dystrophin, which is critical for muscle integrity, is lacking. Stem cells have shown an ability to restore this vital protein.
One major strategy for stem cell treatment of skeletal muscle injury is to directly implant stem cells into the skeletal muscle to help regenerate tissue at the site of injury. This approach is consistent with the effective use of stem cells for the treatment of other types of diseases and disorders. Another strategy, though, is gaining traction for the use of stem cells in skeletal muscle injury. Rather than directly implanting stem cells into the muscle with the hopes of turning these cells into functioning muscle cells, this strategy emphasizes the production of relevant blood vessels – a process called angiogenesis.
By promoting angiogenesis, other cells, known as satellite cells, can be recruited to help with the healing of the skeletal muscle. Stem cells release chemicals that encourage angiogenesis and so can also be used to indirectly repair skeletal muscle.
The use of stem cells in regenerative medicine applies the same general principle to different areas of medicine to help patients. As our understanding of specific disease areas expands and our investigations into how stem cells can be used to address the unique challenges of each medical condition, the more effective our treatments will become. It is an exciting time for those who treat skeletal muscle injury because evidence is accumulating that stem cells may be able to help us address an unmet need and help our patients overcome these injuries, quickly and safely.