Premium
Expression of cyclooxygenase‐1 and ‐2 in IL‐1β‐induced synovitis of the temporomandibular joint
Author(s) -
Satoh K.,
Ogura N.,
Akutsu M.,
Kuboyama N.,
Kuyama K.,
Yamamoto H.,
Kondoh T.
Publication year - 2009
Publication title -
journal of oral pathology and medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.887
H-Index - 83
eISSN - 1600-0714
pISSN - 0904-2512
DOI - 10.1111/j.1600-0714.2008.00733.x
Subject(s) - synovitis , cyclooxygenase , immunohistochemistry , prostaglandin e2 , temporomandibular joint , medicine , prostaglandin e , stimulation , synovial membrane , gene expression , pathology , interleukin , inflammation , cytokine , arthritis , biology , gene , enzyme , biochemistry
Background: In this study, we analyzed the gene expression profile of fibroblast‐like synoviocyte (FLS) cultures from the temporomandibular joint (TMJ) to identify candidate genes associated with intracapsular pathologic conditions of TMJ. Cyclooxygenase (COX)‐2 was one of the genes in FLS upregulated following stimulation by interleukin (IL)‐1β, a cytokine thought to play a key role in several pathological conditions. This study investigated the expression of COX‐1 and COX‐2 in cultured human FLS and rat TMJ synovium following stimulation with IL‐1β. Methods: RNA was isolated from human FLS after IL‐1β treatment. COX‐1 and ‐2 expression was examined using a GeneChip and real‐time polymerase chain reaction. Prostaglandin E 2 (PGE 2 ) levels in conditioned media from FLS were measured using enzyme‐linked immunosorbent assay. Synovial tissues from TMJs of IL‐1β‐injected rats were examined for COX‐1 and COX‐2 expression by immunohistochemical staining. Results: Following treatment of FLS with IL‐1β, expression of the COX‐2 gene increased up to 8 h and peaked at 4 h, whereas COX‐1 expression did not change. Stimulation with IL‐1β increased the level of PGE 2 in conditioned media of cultured FLS in a time‐dependent manner up to 48 h. Immunohistochemistry showed a strong positive staining for COX‐2 in the lining and sub‐lining synovial tissues of the TMJ of IL‐1β‐injected rats. In contrast, staining for COX‐1 was the same in synovial tissues with and without IL‐1β injection. Conclusion: These data suggest that COX‐2 expression stimulated by IL‐1β stimulates the production of PGE 2 in FLS and plays important roles in the progression of inflammation in TMJ.