Aggrecanases are key matrix-degrading enzymes that act by cleaving aggrecan at the Glu(373)-Ala(374) site. While these fragments have been detected in osteoarthritis (OA) and rheumatoid arthritis (RA) cartilage and synovial fluid, no information is available on the regulation or expression of the two key aggrecanases (aggrecanase-1 and aggrecanase-2) in synovial tissue (ST) or fibroblast-like synoviocytes (FLS). The aggrecanase-1 gene was constitutively expressed by both RA and OA FLS. Real-time PCR demonstrated that TGF-beta significantly increased aggrecanase-1 gene expression in FLS. Aggrecanase-1 induction peaked after 24 h of TGF-beta stimulation. The expression of aggrecanase-1 mRNA was significantly greater in RA ST than in OA or nonarthritis ST. Aggrecanase-2 mRNA and protein were constitutively produced by nonarthritis, OA, and RA FLS but were not increased by IL-1, TNF-alpha, or TGF-beta. Furthermore, OA, RA, and nonarthritis ST contained similar amounts of immunoreactive aggrecanase-2. The major form of the aggrecanase-2 enzyme was 70 kDa in nonarthritis ST, whereas a processed 53-kDa form was abundant in RA ST. Therefore, aggrecanase-1 and -2 are differentially regulated in FLS. Both are constitutively expressed, but aggrecanase-1 is induced by cytokines, especially TGF-beta. In contrast, aggrecanase-2 protein may be regulated by a post-translational mechanism in OA and RA ST. Synovial and FLS production of aggrecanase can contribute to cartilage degradation in RA and OA.
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http://dx.doi.org/10.4049/jimmunol.168.3.1405 | DOI Listing |
Am J Sports Med
February 2018
Division for Biochemistry of Joint and Connective Tissue Diseases, Department of Orthopedics, University of Ulm, Ulm, Germany.
Background: Cryotherapy is routinely administered after sports injuries of synovial joints. Although positive clinical effects on periarticular swelling and pain have been described, the effects on the cell biological activities of cartilage and synovial cells remain largely unknown so far.
Hypothesis: Local hypothermia alleviates synovial reactions and prevents chondrocyte death as well as cartilage destructive processes after blunt cartilage trauma.
J Ethnopharmacol
October 2012
Oriental Medicine Research Center for Bone and Joint Disease, East-West Bone and Joint Research Institute, Kyung Hee University, 149 Sangil-dong, Gangdong-gu, Seoul 134-727, Republic of Korea.
Ethnopharmacological Relevance: The dried flowers of Lonicera japonica Thunb and dried roots of Anemarrhena asphodeloides BUNGE have been used for the treatment of a variety of inflammatory diseases in traditional Korean medicine.
Objective: The aim of the study is to evaluate the anti-inflammatory effects of WIN-34B, a new herbal medicine, in fibroblast-like synoviocytes (FLS) obtained from patients with osteoarthritis (OA).
Materials And Methods: WIN-34B is isolated from the n-butanol fraction of dried flowers of L.
Int J Rheum Dis
February 2012
Department of Pathology, Iwate Medical University, Morioka, Shiwa-gun, Japan.
Aim: A disintegrin-like and metalloproteinase with thrombospondin type 1 motif (ADAMTS)-4 and ADAMTS-5 play crucial roles in the cleavage of aggrecan. Several recent studies have demonstrated the effect of cytokines such as interleukin (IL)-1β, tumor necrosis factor-α and transforming growth factor-β on the expression of ADAMTS-4 and ADAMTS-5 in fibroblast-like synoviocytes (FLS). However, the effect of IL-6 remains unclear.
View Article and Find Full Text PDFOsteoarthritis Cartilage
December 2006
Department of Orthopedics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
Objective: Activated synoviocytes play important roles in the progression of human osteoarthritis (OA). Intra-articular injection of high molecular weight hyaluronic acid (HMW-HA) has been used as viscosupplementation for knee OA but its effect on synoviocytes remains undisclosed. This study aims to investigate the effects of HMW-HA on the gene expression of 16 OA-associated cytokines and enzymes, including interleukin (IL)-1beta, IL-6, IL-8, leukemia inhibitory factor (LIF), tumor necrosis factor (TNF)-alpha, TNF-alpha converting enzyme (TACE), matrix metalloproteinase (MMP)-1, MMP-2, MMP-3, MMP-9, MMP-13, tissue inhibitor of metalloproteinase (TIMP)-1, TIMP-2, aggrecanase-1, aggrecanase-2, and inducible nitric oxide synthase (iNOS), in fibroblast-like synoviocytes (FLS) from patients with early stage OA.
View Article and Find Full Text PDFJ Immunol
February 2002
Division of Rheumatology, Allergy, and Immunology, University of California at San Diego School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093, USA.
Aggrecanases are key matrix-degrading enzymes that act by cleaving aggrecan at the Glu(373)-Ala(374) site. While these fragments have been detected in osteoarthritis (OA) and rheumatoid arthritis (RA) cartilage and synovial fluid, no information is available on the regulation or expression of the two key aggrecanases (aggrecanase-1 and aggrecanase-2) in synovial tissue (ST) or fibroblast-like synoviocytes (FLS). The aggrecanase-1 gene was constitutively expressed by both RA and OA FLS.
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