Inducible nitric oxide synthase and apoptosis-related factors in the synovial tissues of temporomandibular joints with internal derangement and osteoarthritis.
OBJECTIVE
In this study, we investigated the relationship between oxidative stress and apoptosis in synovial tissues in temporomandibular joint diseases (TMDs), including internal derangement (ID) and osteoarthritis (OA), comparing immunohistochemical, arthroscopic, and histologic findings.


METHODS
Synovial specimens obtained from patients with ID (31 patients), osteoarthritis (11 patients), and condylar fractures of the mandible (5 patients) during arthroscopy were examined immunohistochemically using antibodies against CD68, inducible nitric oxide synthase (iNOS), Fas, and single-stranded DNA (ssDNA).


RESULTS
CD68 and iNOS immunoreactivity were detected mainly in synovial lining cells and subintimal macrophages, and tended to increase with synovial hyperplasia. Fas and ssDNA immunoreactivity was detected mainly in synovial lining cells, and Fas-positive regions exhibited a number of ssDNA-positive cells. Fas expression was significantly greater in fractures than in OA, and ssDNA expression was significantly greater in OA than in ID. Fas expression was significantly greater in iNOS-positive versus iNOS-negative TMJs, and ssDNA expression tended to increase with iNOS expression.


CONCLUSIONS
These immunohistochemical findings suggest that oxidative stress and apoptosis in synovial tissues are involved in the onset and progression of TMDs.
Nagai
Hiromi
H
Division of Oral Pathology, Department of Oral Medicine and Bioregulation, Tohoku University Graduate School of Dentistry, Sendai, Japan. hiromi-n@cna.ne.jp
Kumamoto
Hiroyuki
H
Fukuda
Masayuki
M
Takahashi
Tetsu
T
D000293:Adolescent; D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000032:analysis; D015214:Antigens, Differentiation, Myelomonocytic / Q000032:analysis; D017209:Apoptosis; D002358:Cartilage, Articular / Q000378:metabolism / Q000473:pathology; D016009:Chi-Square Distribution; D004277:DNA, Single-Stranded / Q000032:analysis; D005260:Female; D006801:Humans; D006965:Hyperplasia; D004204:Joint Dislocations / Q000378:metabolism* / Q000473:pathology; D008264:Macrophages / Q000378:metabolism; D008297:Male; D008335:Mandibular Condyle / Q000293:injuries; D008337:Mandibular Fractures / Q000378:metabolism / Q000473:pathology; D008875:Middle Aged; D019001:Nitric Oxide Synthase / Q000032:analysis*; D052247:Nitric Oxide Synthase Type II; D010003:Osteoarthritis / Q000378:metabolism* / Q000473:pathology; D018384:Oxidative Stress; D013583:Synovial Membrane / Q000378:metabolism*; D013585:Synovitis / Q000378:metabolism; D013704:Temporomandibular Joint / Q000378:metabolism*; D013705:Temporomandibular Joint Disorders / Q000378:metabolism* / Q000473:pathology; D019014:fas Receptor / Q000032:analysis; D000097382:CD68 Molecule
D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D004277:DNA, Single-Stranded; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D019014:fas Receptor; C067980:CD68 antigen, human; D000097382:CD68 Molecule; C496319:NOS2 protein, human