title: 12S-Lipoxygenase is necessary for human vascular smooth muscle cell survival.
abstract: Considerable evidence has been published demonstrating the importance of lipoxygenase enzymes for vascular smooth muscle cell (VSMC) growth. The current study sets out to determine whether or not 12-lipoxygenase (12LO) is also important for human placental VSMC survival. Both a pharmacological and two 12LO antisense knockdown approaches were applied. The 12LO inhibitor baicalien induced a 2-2.5-fold increase in cell death, which appeared to result from apoptosis, as indicated by DNA fragmentation, activation of procaspase 3 to caspase 3 and cytochrome C release from the mitochondria to the cytosol. This apoptosis could be prevented by treatment with the 12LO product, 12 hydroxyeicosatetraenoic acid (12HETE). Human platelet-type 12LO-antisense knockdown, by either plasmid transfection or adeno-associated virus (AAV) infection also induced substantial VSMC death over controls, which could also be prevented by treatment with 12HETE, but not 5HETE. Hence, biochemical 12LO inhibition or 12LO-antisense knockdown in VSMC can induce programmed cell death. These observations suggest a previously unrecognized association between human VSMC survivability and 12LO.
authors.affiliation: Institute of Endocrinology, Metabolism and Hypertension, Tel Aviv Sourasky Medical Center, 6 Weizman Street, Tel Aviv 64239, Israel. gary_w@tasmc.health.gov.il
authors.forename: G
authors.initials: G
authors.lastname: Weisinger
authors.forename: M
authors.initials: M
authors.lastname: Grafi-Cohen
authors.forename: M
authors.initials: M
authors.lastname: Hirsh
authors.forename: E
authors.initials: E
authors.lastname: Knoll
authors.forename: O
authors.initials: O
authors.lastname: Sharon
authors.forename: A
authors.initials: A
authors.lastname: Many
authors.forename: R
authors.initials: R
authors.lastname: Limor
authors.forename: N
authors.initials: N
authors.lastname: Stern
mesh_terms: D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid / Q000494:pharmacology; D017209:Apoptosis; D001092:Arachidonate 12-Lipoxygenase / Q000235:genetics / Q000378:metabolism*; D001692:Biological Transport; D053148:Caspase 3 / Q000378:metabolism; D002470:Cell Survival; D002478:Cells, Cultured; D045304:Cytochromes c / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D000229:Dependovirus / Q000235:genetics / Q000378:metabolism; D044950:Flavanones / Q000494:pharmacology; D055785:Gene Knockdown Techniques; D006801:Humans; D016859:Lipoxygenase Inhibitors / Q000494:pharmacology; D008928:Mitochondria / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology* / Q000201:enzymology; D032389:Myocytes, Smooth Muscle / Q000201:enzymology*; D010957:Plasmids / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014162:Transfection
chemical_list: D018076:DNA, Complementary; D044950:Flavanones; D016859:Lipoxygenase Inhibitors; D024101:Mitochondrial Proteins; D012333:RNA, Messenger; C006680:baicalein; D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; D045304:Cytochromes c; D001092:Arachidonate 12-Lipoxygenase; C476558:ALOX12 protein, human; C505407:CASP3 protein, human; D053148:Caspase 3