Posttranscriptional regulation of collagenase-1 gene expression in synoviocytes by adenosine receptor stimulation.
OBJECTIVE
To characterize the transcriptional and posttranscriptional regulation of collagenase-1 by adenosine receptor stimulation in interleukin-1 (IL-1)-stimulated fibroblast-like synoviocytes (FLS).


METHODS
FLS were stimulated with IL-1 and either the nonselective adenosine agonist 5'-N-ethylcarboxamidoadenosine (NECA) or the adenylate cyclase activator forskolin. Electrophoretic mobility shift assays were performed to determine AP-1 and cAMP-responsive element binding protein (CREB) activation. Transcriptional activation was determined by transfecting HS68 dermal fibroblasts with a collagenase-chloramphenicol acetyltransferase construct. Finally, collagenase messenger RNA (mRNA) half-life was determined by activating cells in the presence of IL-1, IL-1 + NECA, or IL-1 + forskolin and culturing cells in the presence of actinomycin D.


RESULTS
NECA and forskolin had no effect on AP-1 activation, c-jun or c-fos gene expression, or CREB phosphorylation. IL-1 markedly increased collagenase promoter activity, and neither NECA nor forskolin blocked this action. Studies of mRNA half-life showed that both NECA and forskolin decreased the half-life of collagenase mRNA in IL-1-stimulated FLS and HS68 cells.


CONCLUSIONS
The findings of this study demonstrate that NECA and forskolin decrease collagenase gene expression in FLS and dermal fibroblasts due to enhanced mRNA degradation.
Boyle
D L
DL
University of California-San Diego School of Medicine, La Jolla 92093, USA.
Han
Z
Z
Rutter
J L
JL
Brinckerhoff
C E
CE
Firestein
G S
GS
D000241:Adenosine / Q000819:agonists; D019830:Adenosine-5'-(N-ethylcarboxamide) / Q000494:pharmacology; D000262:Adenylyl Cyclases / Q000378:metabolism; D005576:Colforsin / Q000494:pharmacology; D017364:Collagenases / Q000235:genetics*; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D004789:Enzyme Activation; D005786:Gene Expression Regulation; D006207:Half-Life; D006801:Humans; D020781:Matrix Metalloproteinase 1; D011401:Promoter Regions, Genetic / Q000187:drug effects; D011499:Protein Processing, Post-Translational; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D018047:Receptors, Purinergic P1 / Q000502:physiology*; D013583:Synovial Membrane / Q000166:cytology / Q000201:enzymology*; D018808:Transcription Factor AP-1 / Q000378:metabolism
D017362:Cyclic AMP Response Element-Binding Protein; D012333:RNA, Messenger; D018047:Receptors, Purinergic P1; D018808:Transcription Factor AP-1; D005576:Colforsin; D019830:Adenosine-5'-(N-ethylcarboxamide); D017364:Collagenases; D020781:Matrix Metalloproteinase 1; D000262:Adenylyl Cyclases; D000241:Adenosine