Expression of Notch signaling pathway in temporomandibular osteoarthritis

To investigate the expression of Notch signaling molecules in temporomandibular joint arthritis (TMJOA), and to explore the role and mechanism of Notch signaling pathway in the development and progression of TMJOA.

72 Kunming mice were randomly divided into experimental group, sham-surgery group and normal group. In experimental group, discs on the right TMJ were subjected to total discectomy, sham-operation group underwent the same procedure without disc removal, while normal group serve as blank control. All the left temporomandibular joint discs were not treated. 8 mice in each group were sacrificed respectively at 1 week, 2 week, 4 week after surgery. Histological examinations were performed to assess success of TMJOA model, according to the pathological standard of osteoarthritis diagnosis. Immunochemistry techniques were performed in the successful TMJOA cartilages to evaluate the expression levels of Notch1 (NICD1), Jagged1, Hes1 and Hes5. The scores were evaluated by semi-quantitative method.

Notch1 (NICD1), Jagged1 and Hes5 were activated in the experimental group with the expression levels increased dramatically over time. While Hes1 expression was suppressed at the beginning of osteoarthritis but was up-regulated afterwards.

Notch pathway-related molecular expression changed greatly in TMJOA model, indicating that the pathway in the occurrence and development of TMJOA plays an important role.