EVIDENCE has been found that cellular senescence, whereby cells stop dividing, causes osteoarthritis (OA), and that targeting these cells may treat or even prevent the disease. This is according to the findings of a research team from the Robert and Arlene Kogod Center on Aging, Mayo Clinc, Rochester, Minnesota, USA.
OA is a condition that causes pain, swelling, and restricted joint movement due to worn away cartilage; this then causes bones to rub together. It affects approximately 27 million adults in the USA and is consequently the most common form of arthritis. It is most common in people aged ≥65 years, although the condition can affect people of any age. Individuals can also suffer from painful inflammation and cartilage damage. Bone damage may occur as the bones can lose their shape and parts break off and float in the space between the joint.
There is no cure for OA at present, only various therapies that work towards reducing the symptoms. OA patients can be given pain and anti-inflammatory medication, including non-steroidal anti-inflammatory drugs and corticosteroids, and in serious cases joint surgery may be necessary.
The team say the findings from their study are a significant step towards discovering new prevention and treatment methods for OA patients. The study aimed to discover whether there is a causal link between senescence and OA. Senescent cells accumulate with age and lead to a host of age-related diseases.
The researchers injected both senescent and non-senescent cells from the ear cartilage of mice into their knee joints. The injected cells were tracked over 10 days using bioluminescence and fluorodeoxyglucose positron emission tomography imaging. It was found that the mice showed several symptoms of OA, including leg pain, cartilage damage, and restricted mobility, due to a build-up of senescent cells in the rodents’ knee joints. However, these outcomes did not occur as a result of injection with non-senescent cells.
This provides evidence that there is in fact a causal link between senescence and OA, a result not before reached in previous studies. The authors of the study reported: “We believe that targeting senescent cells could be a promising way to prevent or alleviate age-related osteoarthritis. While there is more work to be done, these findings are a critical step toward that goal.”