title: Hyaluronan inhibits matrix metalloproteinase-13 in human arthritic chondrocytes via CD44 and P38.
abstract: We investigated the effects of hyaluronan (HA) on interleukin-1β (IL-1β)-stimulated matrix metalloproteinase (MMP)-13 production in human chondrocytes from patients with osteoarthritis (OA) or rheumatoid arthritis (RA). Secreted levels of MMP-13 in conditioned media were detected by immunoblotting, while intracellular MMP-13 synthesis in articular cartilage was evaluated by immunofluorescence microscopic analysis. Mitogen-activated protein kinases (MAPKs), p38, extracellular signal-regulated kinases (ERK), and c-jun NH2-terminal kinase (JNK) were assessed by Western blotting. IL-1β (2 ng/ml) stimulates the secretion of MMP-13 in both OA and RA chondrocytes. Inhibition studies using specific MAPK inhibitors revealed that IL-1β induced MMP-13 via p38 in both OA and RA chondrocytes. HA down-regulates IL-1β-stimulated MMP-13 and phosphorylated p38 (p-p38) in a dose-dependent manner (0.1, 1, 2, and 4 mg/ml). When used at 4 mg/ml, HA inhibits p-p38 phosphorylation by more than 60%. In response to IL-1β, RA chondrocytes express a higher level of p-p38 than that of OA chondrocytes. Inhibition of CD44, using a blocking antibody, significantly reversed the inhibitory effect of HA on both MMP-13 and p-p38. Our study clearly shows that HA inhibits IL-1β-induced MMP-13 via its principal receptor, CD44, and subsequent intracellular p38 MAPK signaling in OA and RA chondrocytes.
authors: Department of Orthopaedic Surgery, Kyoto University Graduate School of Medicine, Kyoto, Japan. sjulovi@med.usyd.edu.au
authors: Sohel M
authors: SM
authors: Julovi
authors: Hiromu
authors: H
authors: Ito
authors: Kohei
authors: K
authors: Nishitani
authors: Christopher J
authors: CJ
authors: Jackson
authors: Takashi
authors: T
authors: Nakamura
mesh_terms: D001168:Arthritis / Q000188:drug therapy / Q000201:enzymology*; D002478:Cells, Cultured; D019902:Chondrocytes / Q000187:drug effects / Q000201:enzymology; D006801:Humans; D018960:Hyaluronan Receptors / Q000378:metabolism*; D006820:Hyaluronic Acid / Q000494:pharmacology* / Q000627:therapeutic use; D053583:Interleukin-1beta; D053509:Matrix Metalloproteinase 13 / Q000378:metabolism; D061965:Matrix Metalloproteinase Inhibitors; D055675:Viscosupplements / Q000494:pharmacology / Q000627:therapeutic use; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*
chemical_list: C497483:CD44 protein, human; D018960:Hyaluronan Receptors; C508585:IL1B protein, human; D053583:Interleukin-1beta; D061965:Matrix Metalloproteinase Inhibitors; D055675:Viscosupplements; D006820:Hyaluronic Acid; D048051:p38 Mitogen-Activated Protein Kinases; C507079:MMP13 protein, human; D053509:Matrix Metalloproteinase 13