Actions of lipoxins A4 and B4 on signal transduction events in Friend erythroleukemia cells.
Earlier studies in our laboratory suggested a role for 15-lipoxygenase products of arachidonic acid, such as 15-hydroperoxyeicosatetraenoic acid and 15-hydroxyeicosatetraenoic acid, in supporting proliferative events in Friend erythroleukemia cells. Because lipoxins are also products of the same lipoxygenase enzyme, we tested their actions on signal transduction events related to DNA synthesis. Lipoxins A4 and B4 (10 nM) significantly enhanced [3H]thymidine incorporation into Friend cells in the absence of fetal bovine serum without affecting cell differentiation or cell number. Lipoxin B4 increased the duration of time that cells spent in the S phase of the cell cycle, and also significantly enhanced protein kinase C activity in nuclei, whereas c-fos expression was unaffected by either of the lipoxins tested. The novel, intracellular actions of lipoxins A and B on Friend erythroleukemia cells documented in this study represent a unique spectrum of effects of lipoxins on signal transduction events as compared with other eicosanoids.
Beckman
B S
BS
Department of Pharmacology, Tulane University, School of Medicine, New Orleans, Louisiana 70112.
Despinasse
B P
BP
Spriggs
L
L
D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D004789:Enzyme Activation / Q000187:drug effects; D005622:Friend murine leukemia virus; D015870:Gene Expression / Q000187:drug effects; D016762:Genes, fos / Q000235:genetics; D006893:Hydroxyeicosatetraenoic Acids / Q000494:pharmacology*; D004915:Leukemia, Erythroblastic, Acute; D044045:Lipoxins; D011493:Protein Kinase C / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*; D014407:Tumor Cells, Cultured
D006893:Hydroxyeicosatetraenoic Acids; D044045:Lipoxins; C040527:lipoxin A4; C042651:lipoxin B4; D011493:Protein Kinase C