Anti-ageing injection regrows knee cartilage, may stop arthritis early

A new Science study shows that blocking an ageing-linked protein can regenerate knee cartilage and prevent arthritis in mice, raising hopes of injections or pills that could delay joint replacement su

Knee cartilage damage caused by ageing or injury has long been considered irreversible. But a new study published in Science challenges that belief.

 

Titled Inhibition of 15-hydroxy prostaglandin dehydrogenase promotes cartilage regeneration, the research shows that blocking an ageing-related protein can restore knee cartilage in older mice and prevent arthritis after injury. Importantly, human cartilage samples also showed signs of regeneration, suggesting a potential path towards treatments that could delay or even avoid joint replacement surgery.

 

Scientists at Stanford Medicine found that inhibiting a protein called 15-hydroxy prostaglandin dehydrogenase (15-PGDH) triggered robust cartilage regeneration in ageing and injured knees. In older mice, cartilage that had thinned with age thickened again and functioned more like youthful tissue. In mice with knee injuries similar to ACL tears, the treatment stopped osteoarthritis from developing altogether.

 

Why researchers are calling this an anti-ageing cartilage breakthrough

15-PGDH is classified as a “gerozyme”, a protein that becomes more abundant with age and contributes to tissue decline. Earlier work showed that rising levels of this enzyme weaken muscles over time. By blocking it, researchers were able to reverse age-related muscle loss. This new study extends that concept to cartilage, a tissue long believed to have almost no capacity for repair in adults.

How the treatment regenerates cartilage inside the knee

Rather than relying on stem cells, which play a role in regenerating many other tissues, cartilage appears to heal itself by reprogramming existing cells called chondrocytes. When 15-PGDH was inhibited, these cells shifted their gene activity away from inflammation and tissue breakdown and towards forming healthy, smooth articular cartilage, the type that cushions joints and allows pain-free movement.

Why this discovery matters for osteoarthritis treatment

Osteoarthritis affects roughly one in five adults and currently has no disease-modifying treatment. Available therapies focus on managing pain and inflammation, while severe cases often end in knee or hip replacement surgery. By targeting a root cause of cartilage degeneration rather than symptoms, the new approach could potentially slow, stop or even reverse the disease.

Can this approach prevent arthritis after sports injuries?

Yes, at least in animal models. Mice given the 15-PGDH inhibitor after knee injuries were far less likely to develop osteoarthritis than untreated animals. They also moved more normally and put more weight on the injured limb, suggesting real functional improvement, a finding that could be particularly relevant for athletes and physically active adults.

 

The study also shows that cartilage tissue taken from patients undergoing knee replacement surgery showed signs of regeneration after just one week of treatment in the lab. The samples displayed reduced markers of cartilage breakdown and began forming healthier articular cartilage, suggesting the mechanism may translate to humans.

Is the cartilage-regenerating treatment available for patients yet?

Not yet for arthritis. However, a pill-based version of the same 15-PGDH inhibitor is already in early-stage clinical trials for age-related muscle weakness, where it has been shown to be safe and biologically active. Researchers hope similar trials focused on cartilage regeneration will begin soon.

 

If future human trials confirm these results, local injections or oral medications might be able to restore cartilage lost to ageing or injury. While joint replacement will still be necessary for many patients in the near term, this research opens the door to a future where damaged joints can heal themselves rather than be replaced.