UCSF

The Temporomandibular Joint (TMJ) is a robust complex in our body that contains networks of bone and cartilage working together to keep it in a healthy and functional state. The TMJ is subject to various pathological conditions, such as chronic inflammation seen in TMJ Osteoarthritis (TMJ OA), which negatively impacts the joint’s ability to diffuse loads and work properly. This study was created to elucidate the role of osteocytic MMP13 in the progression of TMJ OA, which has signs of both cartilage and subchondral bone deterioration. Given that this model showed that MMP13 OCY-/- mice with OA in the knee had a more severe phenotype than their wildtype counterparts, we predicted the same results in our model. TMJ OA was induced using Monosodium Iodoactetate (MIA) in MMP13 OCY-/- mice and compared the effects to non-injured and saline injected mice. The histological results were remarkable for severe OA in the wildtype MIA group compared to the MMP13 OCY-/- mice, the opposite of what was hypothesized. Furthermore, microCT data was insignificant among all the parameters measured. Our data suggest that the presence of MMP13 has a protective effect on the TMJ cartilage in an osteoarthrtitic state and should be considered for future therapeutic modalities.