EXPRESSION AND ACTIVITY OF ARTICULAR-CARTILAGE HYALURONIDASES

Citation
Cr. Flannery et al., EXPRESSION AND ACTIVITY OF ARTICULAR-CARTILAGE HYALURONIDASES, Biochemical and biophysical research communications (Print), 251(3), 1998, pp. 824-829
Citations number
26
Categorie Soggetti
Biology,Biophysics
ISSN journal
0006291X
Volume
251
Issue
3
Year of publication
1998
Pages
824 - 829
Database
ISI
SICI code
0006-291X(1998)251:3<824:EAAOAH>2.0.ZU;2-T
Abstract
The glycosaminoglycan hyaluronan is an important component of the extr acellular matrix of articular cartilage, contributing to both the stru ctural and functional integrity of this highly specialized tissue. Hya luronan is known to be synthesized and turned over by the resident cho ndrocytes, although the mechanisms involved in hyaluronan degradation are not precisely defined. Recently, the cDNA sequences of extracellul ar hyaluronidases present on spermatazoa and in human serum have been reported, and we have utilized these data to investigate the expressio n and activity of these and/or related enzymes by articular cartilage chondrocytes. By using ''gene-homology'' RT-PCR techniques, three hyal uronidase isozymes were found to be expressed by chondrocytes, and hya luronidase activity was detected in cell membrane extracts and conditi oned media from chondrocyte monolayer cultures following acidification to pH 4.5 or pH 3.7. In addition, the levels of mRNA for two of the c hondrocyte hyaluronidases were upregulated by IL-1 and TNF stimulation , thereby implicating cartilage-derived hyaluronidase activity as a fa ctor contributing to cytokine-induced extracellular matrix degradation during synovial joint disease. (C) 1998 Academic Press.