A NEW drug offers hope to osteoarthritis (OA) patients, as researchers have discovered, based on trials conducted with young mice, that senescent cells can be reduced in joints. Currently, there is no known cure for OA, yet this ground-breaking research provides hope for a new, single-injection fix with the ability to kill senescent cells residing in joints. These senescent cells are an important treatment target as residual senescent cells can cause the development of OA.
Researchers cut the anterior cruciate ligaments of young mice to simulate an injury. The drug used, UBX0101, was injected into the joints of mice 14 days after the initial injury. Gene expression was also monitored, and researchers reported that genes connected to cartilage growth were activated in the rodents’ joints. Senescent cells were reduced by 50% in the mice that received UBX0101.
Next, the team conducted similar experiments on older mice, as their cartilage was thinner in comparison to younger mice. The older mice displayed a higher level of pain at the beginning of the study; however, this was reduced after administration of UBX0101. Signs of cartilage regeneration were not displayed in older mice.
Cultures of cartilage cells were taken from patients with severe OA and grown into three-dimensional (3D) structures, imitating how tissue grows in vivo. These cells were exposed to UBX0101 to observe whether it would have similar effects on humans. Researchers reported that 4 days after the cells were exposed to UBX0101, new cartilage began to form and there was a significant reduction in senescent cells.
Researcher Prof Jennifer Elisseeff, Johns Hopkins Wilmer Eye Institute and Biomedical Engineering, Translational Tissue Engineering Center, Baltimore, Maryland, USA, commented: “What was most striking about the results in human tissue is the fact that removal of senescent cells had a profound effect on tissue from very advanced OA patients, suggesting that even patients with advanced disease could benefit.”
Prof Elisseeff explained why this research is such a great break-through for patients with OA: “Because the drug targets and kills the senescent cells directly, once they are eliminated, patients will not need to return for frequent treatments.” The limited duration that UBX0101 stays in joints posed one limitation of the drug, which highlights an area for further research.