Involvement of ADAMTS5 and hyaluronidase in aggrecan degradation and release from OSM-stimulated cartilage

Abstract

The relative contribution of a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)4 and ADAMTS5 to aggrecan degradation under oncostatin M (OSM) stimulation, the role of the ancillary domains of the aggrecanases on their ability to cleave within the chondroitin sulfate (CS)-2 region, the role of hyaluronidases (HYAL) in stimulating aggrecan release in the absence of proteolysis, and the identity of the hyaluronidase involved in OSM-mediated cartilage breakdown were investigated. Bovine articular cartilage explants were cultured in the presence of interleukin-1β (IL-1β), tumor necrosis factor α (TNFα) and/or OSM, or treated with trypsin and/or hyaluronidase. Aggrecan was digested with various domain-truncated isoforms of ADAMTS4 and ADAMTS5. Aggrecan and link protein degradation and release were analyzed by immunoblotting. Aggrecanase and HYAL gene expression were determined. ADAMTS4 was the most inducible aggrecanase upon cytokine stimulation, whereas ADAMTS5 was the most abundant aggrecanase. ADAMTS5 was the most active aggrecanase and was responsible for the generation of an OSM-specific degradation pattern in the CS-2 region. Its ability to cleave at the OSM-specific site adjacent to the aggrecan G3 region was enhanced by truncation of the Cterminal thrombospondin domain, but reduced by further truncation of both the spacer and cysteine-rich domains of the enzyme. OSM has the ability to mediate proteoglycan release through hyaluronan degradation, under conditions where HYAL-2 is the predominant hyaluronidase being expressed. Compared to other catabolic cytokines, OSM exhibits a unique potential at degrading the proteoglycan aggregate, by promoting early robust aggrecanolysis, primarily through the action of ADAMTS5, and hyaluronan degradation.

Protein kinase R plays a pivotal role in oncostatin M and interleukin-1 signalling in bovine articular cartilage chondrocytes

“…Our fi nding that OSM+IL-1 increased both ADAMTS4 and 5 mRNA expression is consistent with previous studies using bovine cartilage explants Blain et al, 2010;Durigova et al, 2011) and human primary chondrocytes . In addition, Koshy et al (Koshy et al, 2002) reported that OSM+IL-1 induced ADAMTS4 but not ADAMTS5 in T/C28a4 cells (Koshy et al, 2002).…”

“…Our data show that although ADAMTS5 was more highly expressed than ADAMTS4, the OSM+IL-1-induced increases were far greater for ADAMTS4 gene expression compared to ADAMTS5 (830-fold vs. 40-fold). These data, in conjunction with previous fi ndings ( Koshy et al, 2002;Durigova et al, 2011), suggest that ADAMTS4 is the primary aggrecanase responsible for the synergistic action of OSM+IL-1 on aggrecan degradation. We have shown for the fi rst time that OSM+IL-1 induced up-regulation of ADAMTS4 and ADAMTS5 is, in part, mediated through PKR.…”

“…The OSM and IL-1 induced increase in the expression of ADAMTS4 and ADAMTS5 mRNAs in primary articular chondrocytes is mediated, through activation of PKR Since OSM and IL-1 treatment of chondrocytes increases the expression of ADAMTS4 and 5 (Koshy et al, 2002;Milner et al, 2006;Durigova et al, 2008;Durigova et al, 2011), we determined whether this Fig. 2.…”

“…OSM is a member of the interleukin-6 superfamily of cytokines and has been implicated in infl ammatory joint disease (Cawston et al, 1998;Langdon et al, 2000). Several studies have shown that OSM signals synergistically with IL-1 in cartilage, inducing collagen (Cawston et al, 1995) and aggrecan (Cawston et al, 1998;Durigova et al, 2011) degradation via up-regulation of MMPs (Blain et al, 2010;Cawston et al, 1998;Hui et al, 2003;Milner et al, 2006) and ADAMTSs (Hui et al, 2005;El Mabrouk et al, 2007;Durigova et al, 2008;Durigova et al, 2011), respectively. In particular, OSM potently induces MMP13 in human and bovine articular cartilage (Fearon et al, 2006;El Mabrouk et al, 2007;Blain et al, 2010) upregulation of which plays a crucial role in the pathology of degenerative joint disease ( (Little et al, 2009) and reviewed in (Takaishi et al, 2008;van den Berg, 2011)).…”

Inhibition of oncostatin M in osteoarthritic synovial fluid enhances GAG production in osteoarthritic cartilage repair

“…haematopoiesis, neural and liver development and cell proliferation (Miyajima et al, 2000;Tanaka et al, 2003;Tanaka and Umesaki, 2003) and in rheumatoid arthritis (RA), OSM is associated with bone erosion, synovial inflammation and fibrosis, and cartilage degeneration (Sims and Walsh, 2010;Walker et al, 2010). The potential of OSM to degenerate cartilage and induce catabolic processes in chondrocytes was shown in different studies (Barksby et al, 2006;Durigova et al, 2011), although nothing is known about its effect on cartilage synthesis. In addition, OSM is known to synergise with catabolic cytokines such as IL-1 and TNFa in the induction of cartilage degeneration in vitro (Barksby et al, 2006;Catterall et al, 2001;Gilbert et al, 2012;Hui et al, 2001;Hui et al, 2003).…”