Vias WNT Canônica e NF-kB na articulação Temporomandibular de ratos artríticos

Abstract

OBJECTIVE: To investigate the participation of canonical Wnt and NF-κB pathway in an experimental model of rheumatoid arthritis (RA) induced by methylated bovine serum albumin (mBSA) in temporomandibular joint (TMJ). DESIGN: Wistar rats were sensitized by mBSA + Complete Freund Adjuvant (CFA)/Incomplete Freund Adjuvant (IFA) in the first 14 days (1x/week). Subsequently, they received 1, 2 or 3 mBSA or saline solution injections at TMJ (1x/week). Hypernociceptive threshold was performed throughout the experiment using an analgesymeter. After 24 hours of each mBSA injection, the TMJs were removed for histopathological and immunohistochemical analysis for TNF-α, IL-1β, Wnt-10b, β-catenin, DKK-1, NF-κB and Rank-L. RESULTS: The nociceptive threshold showed higher reduction after mBSA injections in the TMJ. However, only after 24 hours of 2 or 3 mBSA injections, significant morphological alterations in the joint were observed, as chronic inflammatory infiltrate in the synovial membrane and in the periarticular tissue. Immunolabeling of TNF-α, IL-1β and Wnt-10b were increased in the synovial membrane in groups that received mBSA booster injections. In contrast, immunoexpression of DKK-1, RANKL and NF-κB were statistically significant only in the group that received 3 injections of mBSA at TMJ. CONCLUSION: The immunoexpression of Wnt-10b and NF-κB suggests their participation in the morphological changes of TMJ during the process of development of RA.