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TNF-? induces matrix metalloproteinase-9-dependent soluble intercellular adhesion molecule-1 release via TRAF2-mediated MAPKs and NF-?B activation in osteoblast-like MC3T3-E1 cells.

ABSTRACT: BACKGROUND: Matrix metalloproteinase-9 (MMP-9) has been shown to be induced by cytokines including TNF-? and may contribute to bone inflammatory diseases. However, the mechanisms underlying MMP-9 expression induced by TNF-? in MC3T3-E1 cells remain unclear. RESULTS: We applied gelatin zymography, Western blot, RT-PCR, real-time PCR, selective pharmacological inhibitors of transcription (actinomycin D, Act.D), translation (cycloheximide, CHI), c-Src (PP1), MEK1/2 (U0126), p38 MAPK (SB202190), JNK1/2 (SP600125), and NF-?B (Bay11-7082), respective siRNAs transfection, promoter assay, immunofluorescence staining, and ELISA to investigate the MMP-9 expression and soluble ICAM-1 (sICAM-1) release induced by TNF-? in MC3T3-E1 cells. Here we demonstrated that TNF-?-induced MMP-9 expression was attenuated by Act.D, CHI, PP1, U0126, SB202190, SP600125, and Bay11-7082, and by the transfection with siRNAs for ERK2, p38 MAPK, and JNK2. TNF-?-stimulated TNFR1, TRAF2, and c-Src complex formation was revealed by immunoprecipitation and Western blot. Furthermore, TNF-?-stimulated NF-?B phosphorylation and translocation were blocked by Bay11-7082, but not by PP1, U0126, SB202190, or SP600125. TNF-? time-dependently induced MMP-9 promoter activity which was also inhibited by PP1, U0126, SB202190, SP600125, or Bay11-7082. Up-regulation of MMP-9 was associated with the release of sICAM-1 into the cultured medium, which was attenuated by the pretreatment with MMP-2/9i, an MMP-9 inhibitor. CONCLUSIONS: In this study, we demonstrated that TNF-? up-regulates MMP-9 expression via c-Src, MAPKs, and NF-?B pathways. In addition, TNF-?-induced MMP-9 expression may contribute to the production of sICAM-1 by MC3T3-E1 cells. The interplay between MMP-9 expression and sICAM-1 release may exert an important role in the regulation of bone inflammatory diseases.

SUBMITTER: Tsai CL

PROVIDER: S-EPMC3926355 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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TNF-α induces matrix metalloproteinase-9-dependent soluble intercellular adhesion molecule-1 release via TRAF2-mediated MAPKs and NF-κB activation in osteoblast-like MC3T3-E1 cells.

Tsai Chia-Lan CL Chen Wei-Chung WC Hsieh Hsi-Lung HL Chi Pei-Ling PL Hsiao Li-Der LD Yang Chuen-Mao CM

Journal of biomedical science 20140205

<h4>Background</h4>Matrix metalloproteinase-9 (MMP-9) has been shown to be induced by cytokines including TNF-α and may contribute to bone inflammatory diseases. However, the mechanisms underlying MMP-9 expression induced by TNF-α in MC3T3-E1 cells remain unclear.<h4>Results</h4>We applied gelatin zymography, Western blot, RT-PCR, real-time PCR, selective pharmacological inhibitors of transcription (actinomycin D, Act.D), translation (cycloheximide, CHI), c-Src (PP1), MEK1/2 (U0126), p38 MAPK (S ...[more]

PMID: 24502696

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Dataset Information

TNF-? induces matrix metalloproteinase-9-dependent soluble intercellular adhesion molecule-1 release via TRAF2-mediated MAPKs and NF-?B activation in osteoblast-like MC3T3-E1 cells.

Publications

TNF-α induces matrix metalloproteinase-9-dependent soluble intercellular adhesion molecule-1 release via TRAF2-mediated MAPKs and NF-κB activation in osteoblast-like MC3T3-E1 cells.

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