title: Extracellular matrix loss in chondrocytes after exposure to interleukin-1β in NADPH oxidase-dependent manner.
abstract: Osteoarthritis is a degenerative joint disease caused by excessive death of chondrocytes and loss of the extracellular matrix (ECM) in articular cartilage. We previously reported that reactive oxygen species (ROS) generated by the NADPH oxidase (NOX) isoform NOX-2 are involved in chondrocyte death induced by interleukin-1β (IL-1β). In this study, we investigate the role of NOX-2 in the production and degradation of ECM by chondrocytes. Although IL-1β lowered the mRNA expression of type II collagen (Col2a1) and aggrecan (Acan) in mouse chondrocyte-like ATDC5 cells, RNA silencing of Nox2 did not change the mRNA expression of these major components of the ECM of cartilage. Hence, NOX-2 is not involved in the IL-1β-induced suppression of ECM production. On the other hand, the NOX inhibitor 4-(2-aminoethyl)benzenesulfonyl fluoride (AEBSF), the ROS scavenger N-acetylcysteine and an antisense oligodeoxynucleotide for Nox2 prevented the loss of proteoglycan induced by IL-1β in highly differentiated ATDC5 cells. Furthermore, AEBSF did not affect the expression of hyaluronidase-1 and -2, whereas it suppressed hyaluronidase activity in culture medium. IL-1β-induced intra- and extracellular acidification was also suppressed by AEBSF, as was the antisense oligodeoxynucleotide for Nox2. Since hyaluronidase activity is known to be higher under acidic conditions, NOX-2 probably contributes to ECM loss by the activation of hyaluronidase through acidification.
authors.affiliation: Department of Biochemistry, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa, Tokyo, 142-8555, Japan.|Department of Prosthodontics, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa, Tokyo, 142-8555, Japan.
authors.forename: Sakie
authors.initials: S
authors.lastname: Funato
authors.affiliation: Division of Pathology, Department of Oral Diagnostic Sciences, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa, Tokyo, 142-8555, Japan.
authors.forename: Rika
authors.initials: R
authors.lastname: Yasuhara
authors.affiliation: Department of Biochemistry, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa, Tokyo, 142-8555, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Yoshimura
authors.affiliation: Department of Biochemistry, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa, Tokyo, 142-8555, Japan. yoichim@dent.showa-u.ac.jp.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Miyamoto
authors.affiliation: Department of Biochemistry, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa, Tokyo, 142-8555, Japan.|Department of Oral and Maxillofacial Surgery, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku, Tokyo, 160-0023, Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Kaneko
authors.affiliation: Department of Biochemistry, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa, Tokyo, 142-8555, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Suzawa
authors.affiliation: Department of Oral and Maxillofacial Surgery, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku, Tokyo, 160-0023, Japan.
authors.forename: Daichi
authors.initials: D
authors.lastname: Chikazu
authors.affiliation: Division of Pathology, Department of Oral Diagnostic Sciences, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa, Tokyo, 142-8555, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Mishima
authors.affiliation: Department of Prosthodontics, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa, Tokyo, 142-8555, Japan.
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Baba
authors.affiliation: Department of Biochemistry, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa, Tokyo, 142-8555, Japan.
authors.forename: Ryutaro
authors.initials: R
authors.lastname: Kamijo
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology; D000143:Acids / Q000378:metabolism; D053674:Aggrecans / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D019902:Chondrocytes / Q000187:drug effects / Q000378:metabolism*; D024043:Collagen Type II / Q000235:genetics / Q000378:metabolism; D003470:Culture Media / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005109:Extracellular Matrix / Q000187:drug effects / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D006820:Hyaluronic Acid / Q000378:metabolism; D006821:Hyaluronoglucosaminidase / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D053583:Interleukin-1beta / Q000494:pharmacology*; D019255:NADPH Oxidases / Q000378:metabolism*; D011509:Proteoglycans / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013450:Sulfones / Q000494:pharmacology
chemical_list: D000143:Acids; D053674:Aggrecans; D024043:Collagen Type II; D003470:Culture Media; D004791:Enzyme Inhibitors; D053583:Interleukin-1beta; D011509:Proteoglycans; D012333:RNA, Messenger; D013450:Sulfones; C002010:4-(2-aminoethyl)benzenesulfonylfluoride; D006820:Hyaluronic Acid; D019255:NADPH Oxidases; D006821:Hyaluronoglucosaminidase; D000111:Acetylcysteine
keywords: Chondrocyte; Extracellular matrix; Hyaluronidase; Interleukin-1β; NADPH oxidase