Group IIA secretory phospholipase A2 is a unique 12/15-lipoxygenase-regulated gene in cytokine-stimulated rat fibroblastic 3Y1 cells.
We have proposed previously that the expression of group IIA secretory phospholipase A(2) (sPLA(2)-IIA), an enzyme implicated in inflammation, is under the control of group IVA cytosolic phospholipase A(2) (cPLA(2)) and 12/15-lipoxygense (12/15-LOX) in cytokine-stimulated rat fibroblastic 3Y1 cells. Here, we show that the reduction of cytokine-stimulated sPLA(2)-IIA induction by the cPLA(2) inhibitor arachidonyl trifluoromethyl ketone (AACOCF(3)) is partially overcome by the addition of various lysophospholipids, such as lysophosphatidylcholine (LysoPC). Furthermore, this lysophospholipid effect was enhanced by further addition of 12/15-LOX products, such as 12(S)- or 15(S)-hydroxyeicosatetraenoic acid (HETE) and 13(S)-hydroxyoctadecadienoic acid (HODE), thus substantiating the hypothesis that the expression of sPLA(2)-IIA is selectively regulated by lipid products of the cPLA(2)-12/15-LOX pathway. In an attempt to identify a set of 12/15-LOX-regulated genes, the cDNA subtraction technique, followed by Northern blotting, was performed to screen particular clones, the expression of which was suppressed by the LOX inhibitor nordihydroguaiaretic acid (NDGA). NDGA-sensitive clones identified thus far included sPLA(2)-IIA, cytoplasmic signaling intermediates, several oxygenases, extracellular matrices, secretory proteins, and other cellular proteins. Of these genes, however, only the expression of sPLA(2)-IIA and 14-3-3eta was enhanced by 12/15-LOX expression. Taken together, our data suggest that sPLA(2)-IIA represents a particular group of genes, the transcription of which is up-regulated by 12/15-LOX metabolites.
Kuwata
Hiroshi
H
Department of Health Chemistry, School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan.
Yamamoto
Shinji
S
Takekura
Akiko
A
Murakami
Makoto
M
Kudo
Ichiro
I
D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology; D002460:Cell Line; D016207:Cytokines / Q000494:pharmacology*; D004790:Enzyme Induction; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects / Q000502:physiology; D054501:Group II Phospholipases A2; D006893:Hydroxyeicosatetraenoic Acids / Q000494:pharmacology; D007375:Interleukin-1 / Q000378:metabolism; D007527:Isoenzymes; D008041:Linoleic Acids / Q000737:chemistry / Q000494:pharmacology; D008084:Lipoxygenase / Q000187:drug effects / Q000502:physiology*; D016859:Lipoxygenase Inhibitors / Q000494:pharmacology; D008246:Lysophospholipids / Q000494:pharmacology; D009637:Masoprocol / Q000494:pharmacology; D047492:Peroxisome Proliferator-Activated Receptors / Q000819:agonists / Q000037:antagonists & inhibitors; D010741:Phospholipases A / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D054467:Phospholipases A2; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D014158:Transcription, Genetic / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D001095:Arachidonic Acids; D016207:Cytokines; D006893:Hydroxyeicosatetraenoic Acids; D007375:Interleukin-1; D007527:Isoenzymes; D008041:Linoleic Acids; D016859:Lipoxygenase Inhibitors; D008246:Lysophospholipids; D047492:Peroxisome Proliferator-Activated Receptors; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; C081565:arachidonyltrifluoromethane; D009637:Masoprocol; D008084:Lipoxygenase; D010741:Phospholipases A; D054501:Group II Phospholipases A2; D054467:Phospholipases A2