title: Role of protein kinase A in collagenase-1 gene regulation by prostaglandin E1: studies in a rabbit synoviocyte cell line, HIG-82.
abstract: Gene expression of the matrix-degrading enzyme collagenase-1 in rabbit synoviocytes and human fibroblasts is down-regulated by prostaglandin E1 (PGE1) through a cyclic adenosine monophosphate (cAMP)-dependent pathway. In the current study, we examined the role of protein kinase A (PKA) in the PGE1-mediated effect on collagenase-1 gene expression. Collagenase-1 gene expression was rapidly induced several-fold above control both by a phorbol ester, 12-o-tetradecanoyl phorbol 13 acetate, and interleukin-1 beta (IL-1 beta) in HIG-82 synoviocytes. Treatment with PGE1 and forskolin increased PKA activity in the HIG-82 cells within 15 minutes of adding the stimulating agents. Two inhibitors of PKA, the isoquinoline-sulfonamide derivative, H-89 and a cAMP analog, RpcAMP, blocked the ability of PGE1 to down-regulate collagenase-1 gene expression. However, if PGE1 was added from 6 h to 30 minutes before the PKA inhibitor H-89, collagenase-1 gene expression was inhibited. Constitutive PKA activity was increased in HIG-82 synoviocytes stably transfected with an expression vector pCMV.C alpha that caused the HIG-82 cells to overexpress an active catalytic subunit of PKA. Cells stably transfected with an inactive, mutated C-alpha-variant showed no change in PKA activity. Collagenase-1 mRNA levels in TPA-stimulated cells were reduced to baseline levels in the pCMV.C alpha but not in the mutated C-alpha-transfected cells. These data show the importance of PKA in regulating collagenase-1 gene expression in a synoviocyte cell line.
authors.affiliation: Hospital for Special Surgery, New York, New York, USA.
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
authors.forename: B E
authors.initials: BE
authors.lastname: Rapuano
authors.forename: R S
authors.initials: RS
authors.lastname: Bockman
mesh_terms: D000527:Alprostadil / Q000494:pharmacology*; D000818:Animals; D002460:Cell Line; D005576:Colforsin / Q000494:pharmacology; D017364:Collagenases / Q000235:genetics*; D000242:Cyclic AMP / Q000031:analogs & derivatives / Q000494:pharmacology; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D004790:Enzyme Induction; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D007527:Isoenzymes / Q000235:genetics; D007546:Isoquinolines / Q000494:pharmacology; D020781:Matrix Metalloproteinase 1; D011493:Protein Kinase C / Q000235:genetics; D051571:Protein Kinase C-alpha; D012333:RNA, Messenger / Q000378:metabolism; D011817:Rabbits; D013449:Sulfonamides; D013583:Synovial Membrane / Q000166:cytology / Q000201:enzymology*; D013873:Thionucleotides / Q000494:pharmacology; D014162:Transfection
chemical_list: D004791:Enzyme Inhibitors; D007375:Interleukin-1; D007527:Isoenzymes; D007546:Isoquinolines; D012333:RNA, Messenger; D013449:Sulfonamides; D013873:Thionucleotides; D005576:Colforsin; C016957:adenosine-3',5'-cyclic phosphorothioate; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; C496628:PRKCA protein, human; D011493:Protein Kinase C; D051571:Protein Kinase C-alpha; D017364:Collagenases; D020781:Matrix Metalloproteinase 1; D000527:Alprostadil; C063509:N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide