Expression of cyclooxygenase-1 and -2 in IL-1beta-induced synovitis of the temporomandibular joint

• Published in: Journal of oral pathology & medicine 2009-08, Vol.38 (7), p.584-590
• Main Authors: Satoh, K, Ogura, N, Akutsu, M, Kuboyama, N, Kuyama, K, Yamamoto, H, Kondoh, T
• Format: Article
• Language: English
• Subjects: Adult; Animals; Cells, Cultured; Cyclooxygenase 1 - genetics; Cyclooxygenase 1 - metabolism; Cyclooxygenase 2 - genetics; Cyclooxygenase 2 - metabolism; Dentistry; Disease Models, Animal; Female; Fibroblasts - cytology; Fibroblasts - immunology; Fibroblasts - metabolism; Gene Expression Profiling; Gene Expression Regulation - immunology; Humans; Immunohistochemistry; Interleukin-1beta - metabolism; Male; Oligonucleotide Array Sequence Analysis; Rats; RNA - analysis; Synovial Membrane - cytology; Synovial Membrane - immunology; Synovial Membrane - metabolism; Synovitis - immunology; Synovitis - metabolism; Synovitis - pathology; Temporomandibular Joint - cytology; Temporomandibular Joint - immunology; Temporomandibular Joint - metabolism; Temporomandibular Joint Disorders - immunology; Temporomandibular Joint Disorders - metabolism; Temporomandibular Joint Disorders - pathology; Young Adult
• ISSN: 1600-0714
• DOI: 10.1111/j.1600-0714.2008.00733.x

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)-1beta, 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-1beta. RNA was isolated from human FLS after IL-1beta 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-1beta-injected rats were examined for COX-1 and COX-2 expression by immunohistochemical staining. Following treatment of FLS with IL-1beta, 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-1beta 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-1beta-injected rats. In contrast, staining for COX-1 was the same in synovial tissues with and without IL-1beta injection. These data suggest that COX-2 expression stimulated by IL-1beta stimulates the production of PGE(2) in FLS and plays important roles in the progression of inflammation in TMJ.