Effect of hypoxia and interleukin-1beta on expression of tenascin-C in temporomandibular joint.
OBJECTIVE
The expression of tenascin-C in the synovial membrane of the internal derangement (ID) of the temporomandibular joint (TMJ) has been reported. Hypoxia of the synovial membrane in TMJ is considered to be a cause for the pathophysiology of ID. In this study, we clarify the contribution of hypoxia and interleukin-1beta in the expression of tenascin-C in ID of TMJ.


METHODS
Synovial fibroblasts and disk cells obtained from ID of TMJs were cultured and treated with interleukin-1beta under normoxia and hypoxia. A Western blot analysis and reverse transcription-polymerase chain reaction analysis were used to identify tenascin-C in cultured synovial fibroblasts and disk cells. In addition, the immunohistochemical staining of tenascin-C was carried out for the specimens of ID of TMJs and normal.


RESULTS
The combination of hypoxia and interleukin-1beta caused a significant increase in tenascin-C protein and mRNA of synovial fibroblasts. In contrast, the combination caused no increase in tenascin-C in disk cells. However, the immunohistochemical staining demonstrated tenascin-C to be significantly detected in both the synovial tissue and disks in ID of TMJ.


CONCLUSIONS
These results indicate that hypoxic conditions with inflammation modulate the tenascin-C expression in synovial fibroblasts, but not in disk cells.
Tojyo
I
I
Department of Oral and Maxillofacial Surgery, Wakayama Medical University, Wakayama, Japan. kagoky@wakayama-med.ac.jp
Yamaguchi
A
A
Nitta
T
T
Yoshida
H
H
Fujita
S
S
Yoshida
T
T
D000328:Adult; D000368:Aged; D015153:Blotting, Western; D002478:Cells, Cultured; D016895:Culture Media, Serum-Free; D005347:Fibroblasts / Q000473:pathology; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology*; D007150:Immunohistochemistry; D053583:Interleukin-1beta / Q000494:pharmacology*; D004204:Joint Dislocations / Q000473:pathology*; D008875:Middle Aged; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013583:Synovial Membrane / Q000473:pathology; D013585:Synovitis / Q000473:pathology; D019224:Temporomandibular Joint Disc / Q000473:pathology; D013705:Temporomandibular Joint Disorders / Q000473:pathology*; D019063:Tenascin / Q000032:analysis*; D015854:Up-Regulation
D016895:Culture Media, Serum-Free; D053583:Interleukin-1beta; D019063:Tenascin