Methods: Fifty-six rats were randomly divided into seven groups of eight: no treatment (NT), then CFA-only treatment (CFA), IL-17 antibody-only treatment (IL), or CFA+IL-17 antibody (CFA+IL) for two time periods each, either two or seven days. For antibody neutralization experiments, anti-IL-17 antibody was injected into rats on days 1 and 6 following the CFA injection. The rats were sacrificed and TMJ tissues were extirpated bilaterally, homogenized, and then analyzed. Quantitative measurement of IL-17 and IL-23 was performed in duplicate using ELISA.
Results: Histological analysis revealed a high inflammatory response in the CFA-only-treated groups and a significantly decreased response in the CFA+IL-17 antibody-treated groups. ELISA revealed increased levels of IL-17 and IL-23 in the inflamed TMJ (p≤0.05). Neutralizing antibody treatment produced a significant reduction in both IL-17 and IL-23 levels (p≤0.05).
This study demonstrated that IL-17 plays a vital role in the cascade of TMJ inflammation, potentially through the activation of IL-23, and that anti-IL-17 treatment may be a potential therapeutic treatment for those with TMJ disorders. Supported by the Baylor Oral Health Foundation.
Keywords: Cytokine, Inflammation, Inflammatory mediators and TMJ and masticatory muscles