In a groundbreaking multidisciplinary study, researchers at the Wyss Institute for Biologically Inspired Engineering and the Harvard John A. Paulson School of Engineering and Applied Sciences have uncovered a key to healing muscle injuries in senior people. While mechanical therapy, including advanced massage techniques, has long been used in physical therapy, its effectiveness on elderly patients has been unclear.
Led by Wyss core faculty member David Mooney and associate faculty member Conor Walsh, the team developed a robotic mechanotherapy device that could precisely deliver mechanotherapy to injured muscles in mice, similar to an advanced massage gun. Surprisingly, the study found that mechanotherapy accelerated muscle healing in young animals by reducing inflammation, but had the opposite effect on aged muscle, exacerbating injuries.
Further investigation revealed that mechanotherapy amplified inflammation in aged muscle, disrupting the behavior of muscle stem cells responsible for tissue repair. To address this, the researchers combined mechanotherapy with anti-inflammatory treatment, significantly improving healing in aged muscles. These findings, published in Science Robotics, open up noninvasive therapeutic possibilities for elderly patients.
Mooney, also the Robert P. Pinkas Family Professor of Bioengineering at SEAS, emphasised the need for tailored approaches: "Muscle mechanotherapies likely won't be a 'one-size-fits-all.' To realise their benefits, they will have to be tailored to patient populations, and specifically for aged individuals, it will be key to modulate inflammation."
The study also shed light on how mechanical load influences muscle cell behavior and stem cells, prompting the team to explore personalised mechanotherapeutic approaches for injury healing across all ages. The research was funded by various institutions, including the National Institute of Dental and Craniofacial Research and the National Institutes of Health.
This discovery holds the promise of enhancing the recovery of elderly suffering from muscle injuries and reshaping the future of mechanotherapies.
Other authors on the study are additional members of Mooney and Walsh’s groups, including Bo Ri Seo, Benjamin Freedman, Emily Roloson, Jonathan Alvarez, C.T. O’Neill, and Herman Vandenburgh, professor emeritus at Brown University, Providence, Rhode Island.
The study was funded by the National Institute of Dental and Craniofacial Research (under grant #R01DE013349), National Science Foundation (under grant #DMR-1420570), National Institute of Arthritis and Musculoskeletal and Skin Disease (under grant #F31AR075367), National Institutes of Health (under grant #K99AG065495), National Institute of General Medical Sciences (under award #T32GM007753 and T32GM144273), as well as an AR3T Regenerative Rehabilitation pilot grant.