Retinoic acid treatment elevates matrix metalloproteinase-2 protein and mRNA levels in avian growth plate chondrocyte cultures.
Matrix metalloproteinases (MMPs) play a crucial role in tissue remodeling. In growth plate (GP) cartilage, extensive remodeling occurs at the calcification front. To study the potential involvement of MMPs in retinoic acid (RA) regulation of skeletal development, we studied the effect of all-trans-RA on MMPs levels in mineralizing chicken epiphyseal chondrocyte primary cultures. When treated for 4 day periods on days 10 and 17, RA increased levels of an approximately 70 kDa gelatinase activity. The N-terminal sequence of the first 20 amino acid residues of the purified enzyme was identical to that deduced from chicken MMP-2 cDNA. Time-course studies indicated that RA elevated MMP-2 activity levels in the cultures within 16 h. This increase was inhibited by cycloheximide and was enhanced by forskolin. The increase in MMP-2 activity induced by RA was accompanied by an increase in MMP-2 mRNA levels and was abolished by treatment with cycloheximide. This upregulation of MMP levels by RA in GP chondrocytes is consistent with its effects on osteoblasts and osteosarcoma cells and opposite its inhibitory effects on fibroblasts and endothelial cells. It may well be related to the breakdown of the extracellular matrix in the GP and would be governed by the availability of RA at the calcification front where extensive vascularization also occurs.
Nie
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Department of Chemistry and Biochemistry, University of South Carolina, Columbia 29208, USA.
Ishikawa
Y
Y
Yoshimori
T
T
Wuthier
R E
RE
Wu
L N
LN
D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D002645:Chickens; D019902:Chondrocytes / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology*; D017364:Collagenases / Q000032:analysis; D018093:Gelatinases / Q000032:analysis / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression / Q000187:drug effects; D006132:Growth Plate / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology*; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D008666:Metalloendopeptidases / Q000032:analysis / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000187:drug effects* / Q000378:metabolism*; D013997:Time Factors; D014212:Tretinoin / Q000494:pharmacology*; D015854:Up-Regulation / Q000502:physiology
D012333:RNA, Messenger; D014212:Tretinoin; D017364:Collagenases; D018093:Gelatinases; D008666:Metalloendopeptidases; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9