One of the most significant challenges of aging is the deterioration of joints, leading to pain and inflammation. For decades, it was believed that once cartilage in a joint had broken down, it could not be regrown. However, scientists at Stanford University have made a groundbreaking discovery that could change this understanding.
Researchers have identified a protein called 15-PGDH, which is linked to aging and interferes with tissue repair and inflammation reduction. When this protein was blocked in mice, old and worn-down cartilage began to thicken again. This breakthrough could have significant implications for the treatment of osteoarthritis, a condition caused by cartilage breakdown.
Understanding the Role of 15-PGDH
The Stanford team found that 15-PGDH becomes more abundant with age and hinders the molecules responsible for tissue repair and inflammation reduction. By blocking this protein, the researchers were able to regenerate cartilage in old mice and prevent arthritis in young mice with fresh injuries. This was achieved without the involvement of stem cells, as the adult cells responsible for building and maintaining cartilage, called chondrocytes, were able to become healthier once 15-PGDH was reduced.
According to Stanford University stem cell biologist Helen Blau, this discovery represents a new way of regenerating adult tissue and has significant clinical promise for treating arthritis caused by aging or injury. The team also tested the approach on human cartilage taken from people undergoing knee replacement surgery and observed the same pattern, with tissue becoming stiffer and less inflamed after treatment.
Broader Implications and Ongoing Research
This breakthrough is part of a larger effort to combat osteoarthritis, with the US government’s Advanced Research Projects Agency for Health (ARPA-H) investing over $100 million in several teams working towards the same goal. One of the recipients of the grants, the University of Colorado Boulder, has developed a slow-release drug-delivery system that can repair cartilage and bone in animals. Another team at Columbia University is using 3D-printing to create a living human knee scaffold seeded with stem cells that dissolves as the body regrows its own cartilage and bone.
In addition to these developments, a 2026 study found that the drug semaglutide may protect joints by reprogramming the metabolism of cells that maintain healthy cartilage. This could provide a potential treatment that is already widely in use. While more research is needed, the fact that many people already take semaglutide makes it an attractive candidate for further study.
Next Steps and Future Prospects
The Stanford team plans to proceed with a clinical trial, which could be expedited by the fact that a 15-PGDH blocker has already been tested in a previous human trial without raising any health and safety concerns. The potential breakthrough has significant implications for the treatment of osteoarthritis, and the researchers are excited about the possibility of regrowing existing cartilage and avoiding joint replacement. As the study was published in the journal Science, the scientific community will be eagerly awaiting the results of the clinical trial and the potential impact on the lives of people suffering from osteoarthritis.
Helene Elliott is the senior reporter for News Raise. She covers Science news. She also has a keen interest in photojournalism. Helene holds a nomination for the prestigious Red Smith Award. She is married to author Dennis D’Agostino, a former publicist with the New York Mets.
