Effects of IL-6 and soluble IL-6 receptor on the expression of cartilage matrix proteins in human chondrocytes.
Elevated concentrations of interleukin (IL)-6 and soluble IL-6 receptor (sIL-6Ralpha) in synovial fluid have been implicated in joint cartilage destruction. We examined the effect of IL-6 and sIL-6Ralpha on cell growth, alkaline phosphatase (ALPase) activity, and the expression of Sox-9, type II collagen, aggrecan core, link protein, BMP-7, and BMP receptors in human chondrocytes. Cell proliferation increased slightly in the presence of both IL-6 and sIL-6Ralpha, whereas ALPase activity decreased markedly. The expression of Sox-9 and aggrecan core did not change in the presence or absence of IL-6 and sIL-6Ralpha, whereas the expression of type II collagen, link protein, BMP-7, and BMP receptors increased in the presence of both IL-6 and sIL-6Ralpha. These results suggest that IL-6 and sIL-6Ralpha suppress the differentiation of chondrocytes and induce the repair of arthrodial cartilage through an increase in the expression of cartilage matrix proteins, BMP-7, and BMP receptors in the cells.
Namba
Aki
A
Department of Oral and Maxillofacial Surgery, Nihon University School of Dentistry, Tokyo, Japan.
Aida
Yukiko
Y
Suzuki
Naoto
N
Watanabe
Yusuke
Y
Kawato
Takayuki
T
Motohashi
Masafumi
M
Maeno
Masao
M
Matsumura
Hideo
H
Matsumoto
Mitsuhiko
M
D000469:Alkaline Phosphatase / Q000096:biosynthesis; D055419:Bone Morphogenetic Protein 7; D052004:Bone Morphogenetic Protein Receptors / Q000096:biosynthesis; D019485:Bone Morphogenetic Proteins / Q000096:biosynthesis; D002460:Cell Line; D049109:Cell Proliferation; D019902:Chondrocytes / Q000166:cytology / Q000378:metabolism*; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis*; D006609:High Mobility Group Proteins / Q000096:biosynthesis; D006801:Humans; D015850:Interleukin-6 / Q000494:pharmacology*; D019947:Receptors, Interleukin-6 / Q000378:metabolism*; D055758:SOX9 Transcription Factor; D014157:Transcription Factors / Q000096:biosynthesis
C525819:BMP7 protein, human; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D016326:Extracellular Matrix Proteins; D006609:High Mobility Group Proteins; D015850:Interleukin-6; D019947:Receptors, Interleukin-6; D055758:SOX9 Transcription Factor; C527932:SOX9 protein, human; D014157:Transcription Factors; C113250:interleukin-6 receptor alpha; D052004:Bone Morphogenetic Protein Receptors; D000469:Alkaline Phosphatase