PT  - JOURNAL ARTICLE
AU  - Yutaka Nakoshi
AU  - Masahiro Hasegawa
AU  - Akihiro Sudo
AU  - Toshimichi Yoshida
AU  - Atsumasa Uchida
TI  - Regulation of tenascin-C expression by tumor necrosis factor-alpha in cultured human osteoarthritis chondrocytes.
DP  - 2008 Jan 01
TA  - The Journal of Rheumatology
PG  - 147--152
VI  - 35
IP  - 1
4099  - http://www.jrheum.org/content/35/1/147.short
4100  - http://www.jrheum.org/content/35/1/147.full
SO  - J Rheumatol2008 Jan 01; 35
AB  - Expression of tenascin-C reappears in articular cartilage of persons with osteoarthritis (OA), while it is almost abolished in normal mature cartilage. Tumor necrosis factor-alpha (TNF-alpha), a proinflammatory cytokine, is upregulated in OA cartilage and is involved in the progression of OA, and stimulates tenascin-C expression in other types of cells. We investigated regulation of tenascin-C expression by TNF-alpha through nuclear factor-alphaB (NF-kappaB) in OA cartilage in vivo and in vitro. METHODS: Human articular cartilages were obtained from patients with OA and immunofluorescence examination of tenascin-C and the activated RelA subunit was performed. Cultured chondrocytes isolated from human OA cartilage were treated with TNF-alpha and with SN50. Activation of RelA subunit of NF-kappaB was examined by immunolabeling. Changes in tenascin-C protein concentrations were determined by immunofluorescence of cells after monensin treatment and Western blot analysis of the cell lysates, and mRNA levels were analyzed by quantitative real-time polymerase chain reaction. RESULTS: Increased intensity of tenascin-C staining was observed in the damaged cartilage compared with normal cartilage. Activated RelA staining in chondrocyte nuclei was prominent in tenascin-C-positive areas of OA cartilage. Treatment of cultured chondrocytes by TNF-alpha induced translocation of activated RelA to the nuclei, followed by upregulation of tenascin-C expression in both mRNA and protein. Treatment with SN50 inhibited increases of RelA and tenascin-C expression in chondrocytes. CONCLUSION: TNF-alpha stimulated tenascin-C expression through NF-kappaB signaling with RelA activation in cultured OA chondrocytes, suggesting involvement of tenascin-C in OA cartilage remodeling.