1
|
Roy J, Oger C, Thireau J, Roussel J, Mercier-Touzet O, Faure D, Pinot E, Farah C, Taber DF, Cristol JP, Lee JCY, Lacampagne A, Galano JM, Durand T, Le Guennec JY. Nonenzymatic lipid mediators, neuroprostanes, exert the antiarrhythmic properties of docosahexaenoic acid. Free Radic Biol Med 2015; 86:269-78. [PMID: 25911196 DOI: 10.1016/j.freeradbiomed.2015.04.014] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 03/18/2015] [Accepted: 04/11/2015] [Indexed: 12/21/2022]
Abstract
Neuroprostanes are lipid mediators produced by nonenzymatic free radical peroxidation of docosahexaenoic acid (DHA). DHA is associated with a lower atherosclerosis risk, suggesting a beneficial role in cardiovascular diseases. The aim of this study was to investigate the influence of DHA peroxidation on its potentially antiarrhythmic properties (AAP) in isolated ventricular cardiomyocytes and in vivo in post-myocardial infarcted mice. Calcium imaging and biochemical experiments indicate that cardiac arrhythmias induced by isoproterenol are associated with Ca(2+) leak from the sarcoplasmic reticulum after oxidation and phosphorylation of the type 2 ryanodine receptor (RyR2) leading to dissociation of the FKBP12.6/RyR2 complex. Both oxidized DHA and 4(RS)-4-F4t-NeuroP prevented cellular arrhythmias and posttranslational modifications of the RyR2 leading to a stabilized FKBP12.6/RyR2 complex. DHA per se did not have AAP. The AAP of 4(RS)-4-F4t-NeuroP was also observed in vivo. In this study, we challenged the paradigm that spontaneously formed oxygenated metabolites of lipids are undesirable as they are unconditionally toxic. This study reveals that the lipid mediator 4(RS)-4-F4t-neuroprostane derived from nonenzymatic peroxidation of docosahexaenoic acid can counteract such deleterious effects through cardiac antiarrhythmic properties. Our findings demonstrate 4(RS)-4-F4t-NeuroP as a mediator of the cardioprotective AAP of DHA. This discovery opens new perspectives for products of nonenzymatic oxidized ω3 polyunsaturated fatty acids as potent mediators in diseases that involve ryanodine complex destabilization such as ischemic events.
Collapse
Affiliation(s)
- Jérôme Roy
- INSERM U1046-UMR 9214, Centre National de la Recherche Scientifique, Physiologie et Médecine Expérimentale du Coeur et des Muscles, Université de Montpellier, 34295 Montpellier Cedex 5, France
| | - Camille Oger
- Institut des Biomolécules Max Mousseron, UMR 5247, Centre National de la Recherche Scientifique, Université de Montpellier, ENSCM, Montpellier, France
| | - Jérôme Thireau
- Institut des Biomolécules Max Mousseron, UMR 5247, Centre National de la Recherche Scientifique, Université de Montpellier, ENSCM, Montpellier, France
| | - Julien Roussel
- INSERM U1046-UMR 9214, Centre National de la Recherche Scientifique, Physiologie et Médecine Expérimentale du Coeur et des Muscles, Université de Montpellier, 34295 Montpellier Cedex 5, France
| | - Olivia Mercier-Touzet
- INSERM U1046-UMR 9214, Centre National de la Recherche Scientifique, Physiologie et Médecine Expérimentale du Coeur et des Muscles, Université de Montpellier, 34295 Montpellier Cedex 5, France
| | - Delinger Faure
- INSERM U1046-UMR 9214, Centre National de la Recherche Scientifique, Physiologie et Médecine Expérimentale du Coeur et des Muscles, Université de Montpellier, 34295 Montpellier Cedex 5, France; Institut des Biomolécules Max Mousseron, UMR 5247, Centre National de la Recherche Scientifique, Université de Montpellier, ENSCM, Montpellier, France
| | - Edith Pinot
- Institut des Biomolécules Max Mousseron, UMR 5247, Centre National de la Recherche Scientifique, Université de Montpellier, ENSCM, Montpellier, France
| | - Charlotte Farah
- INSERM U1046-UMR 9214, Centre National de la Recherche Scientifique, Physiologie et Médecine Expérimentale du Coeur et des Muscles, Université de Montpellier, 34295 Montpellier Cedex 5, France
| | - Douglass F Taber
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
| | - Jean-Paul Cristol
- INSERM U1046-UMR 9214, Centre National de la Recherche Scientifique, Physiologie et Médecine Expérimentale du Coeur et des Muscles, Université de Montpellier, 34295 Montpellier Cedex 5, France
| | - Jetty C Y Lee
- School of Biological Sciences, The University of Hong Kong, Hong Kong, SAR
| | - Alain Lacampagne
- INSERM U1046-UMR 9214, Centre National de la Recherche Scientifique, Physiologie et Médecine Expérimentale du Coeur et des Muscles, Université de Montpellier, 34295 Montpellier Cedex 5, France
| | - Jean-Marie Galano
- Institut des Biomolécules Max Mousseron, UMR 5247, Centre National de la Recherche Scientifique, Université de Montpellier, ENSCM, Montpellier, France
| | - Thierry Durand
- Institut des Biomolécules Max Mousseron, UMR 5247, Centre National de la Recherche Scientifique, Université de Montpellier, ENSCM, Montpellier, France
| | - Jean-Yves Le Guennec
- INSERM U1046-UMR 9214, Centre National de la Recherche Scientifique, Physiologie et Médecine Expérimentale du Coeur et des Muscles, Université de Montpellier, 34295 Montpellier Cedex 5, France.
| |
Collapse
|
2
|
Irusta G, Murphy MJ, Perez WD, Hennebold JD. Dynamic expression of epoxyeicosatrienoic acid synthesizing and metabolizing enzymes in the primate corpus luteum. Mol Hum Reprod 2007; 13:541-8. [PMID: 17567599 DOI: 10.1093/molehr/gam044] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Epoxyeicosatrienoic acids (EpETrEs), produced from arachidonic acid via cytochrome P450 (CYP) epoxygenases, regulate inflammation, angiogenesis, cellular proliferation, ion transport and steroidogenesis. EpETrE actions are regulated through their metabolism to diols (dihydroxyeicosatrienoic acids; DiHETrE) via the enzyme soluble epoxide hydrolase (EPHX2). We set out to determine, therefore, whether EpETrE generating (epoxygenases CYP2C8, 2C9, 2C19, 2J2, 1A2 and 3A4) and metabolizing (EPHX2) enzymes are expressed in the primate corpus luteum (CL). CL were isolated from rhesus macaques during the early (day 3-5 post-LH surge), mid (day 6-8), mid-late (day 10-12), late (day 14-16) and very-late (day 17-19: menses) luteal phase of natural menstrual cycles. EPHX2 mRNA levels peaked in mid-late CL (5-fold when compared with early CL, P<0.05) and remained elevated in the late CL. Ablation of pituitary LH secretion and luteal steroid synthesis significantly reduced (P<0.05) EPHX2 mRNA levels in the mid-late CL, with progestin replacement being insufficient to restore its level of expression to control values. EPHX2 protein was localized to large and small luteal cells, as well as vascular endothelial cells. The EpETrE-generating CYP epoxygenase 2J2, 2C9 and 3A4 genes were also expressed in the macaque CL. While CYP2J2 mRNA levels did not significantly change through the luteal phase, CYP2C9 and CYP3A4 levels were significantly (P<0.05) higher in the mid-late phase when compared with the early phase. CYP2C9, 2J2 and 3A4 proteins were each localized to the large luteal cells, with 2C9 and 2J2 also being present in the small luteal, stromal and endothelial cells. These studies demonstrate for the first time that an EpETrE generating and metabolizing system exists in the primate CL, with the latter being regulated by LH and steroid hormone(s).
Collapse
Affiliation(s)
- G Irusta
- Division of Reproductive Sciences, Oregon National Primate Research Center, Oregon Health and Science University, West Campus, Beaverton, OR 97006, USA
| | | | | | | |
Collapse
|
3
|
Rifkind AB. CYP1A in TCDD toxicity and in physiology-with particular reference to CYP dependent arachidonic acid metabolism and other endogenous substrates. Drug Metab Rev 2006; 38:291-335. [PMID: 16684662 DOI: 10.1080/03602530600570107] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Toxicologic and physiologic roles of CYP1A enzyme induction, the major biochemical effect of aryl hydrocarbon receptor activation by TCDD and other receptor ligands, are unknown. Evidence is presented that CYP1A exerts biologic effects via metabolism of endogenous substrates (i.e., arachidonic acid, other eicosanoids, estrogens, bilirubin, and melatonin), production of reactive oxygen, and effects on K(+) and Ca(2+) channels. These interrelated pathways may connect CYP1A induction to TCDD toxicities, including cardiotoxicity, vascular dysfunction, and wasting. They may also underlie homeostatic roles for CYP1A, especially when transiently induced by common chemical exposures and environmental conditions (i.e., tryptophan photoproducts, dietary indoles, and changes in oxygen tension).
Collapse
Affiliation(s)
- Arleen B Rifkind
- Department of Pharmacology, Weill Medical College of Cornell University, New York, NY 10021, USA.
| |
Collapse
|
4
|
Hennebold JD, Mah K, Perez W, Vance JE, Stouffer RL, Morisseau C, Hammock BD, Adashi EY. Identification and Characterization of an Ovary-Selective Isoform of Epoxide Hydrolase1. Biol Reprod 2005; 72:968-75. [PMID: 15601917 DOI: 10.1095/biolreprod.104.035899] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
A novel ovary-selective gene was identified by suppression subtractive hybridization (SSH) that is expressed only during the mouse periovulatory phase of a stimulated estrous cycle. Analysis of the protein encoded by the full-length cDNA revealed that the majority of it, with the exception of the first 44 amino acids, matched soluble epoxide hydrolase (Ephx2, referred to as Ephx2A). By comparing the cDNA sequence of this newly identified variant of soluble epoxide hydrolase (referred to as Ephx2B) with the mouse genome database, an exon was identified that corresponds to its unique 5' cDNA sequence. Through the use of an Ephx2A-specific probe, Northern blot analysis revealed that this mRNA was also expressed in the ovary, with the highest level of expression occurring during the luteal phase of a stimulated estrous cycle. In situ hybridization revealed that Ephx2B mRNA expression was restricted to granulosa cells of preovulatory follicles. Ephx2A mRNA expression, however, was detectable in follicles at different stages of development, as well as in the corpus luteum. Total ovarian epoxide hydrolase activity increased following the induction of follicular development, and remained elevated through the periovulatory and postovulatory stages of a stimulated estrous cycle. The change in enzyme activity paralleled the combined mRNA expression profiles for both Ephx2A and Ephx2B, thus supporting a role for epoxide metabolism in ovarian function.
Collapse
Affiliation(s)
- Jon D Hennebold
- Division of Reproductive Sciences, Oregon National Primate Research Center, Beaverton, Oregon 97006, USA.
| | | | | | | | | | | | | | | |
Collapse
|
5
|
Fang X, Weintraub NL, McCaw RB, Hu S, Harmon SD, Rice JB, Hammock BD, Spector AA. Effect of soluble epoxide hydrolase inhibition on epoxyeicosatrienoic acid metabolism in human blood vessels. Am J Physiol Heart Circ Physiol 2004; 287:H2412-20. [PMID: 15284062 DOI: 10.1152/ajpheart.00527.2004] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We investigated the effects of soluble epoxide hydrolase (sEH) inhibition on epoxyeicosatrienoic acid (EET) metabolism in intact human blood vessels, including the human saphenous vein (HSV), coronary artery (HCA), and aorta (HA). When HSV segments were perfused with 2 micromol/l 14,15-[3H]EET for 4 h, >60% of radioactivity in the perfusion medium was converted to 14,15-dihydroxyeicosatrienoic acid (DHET). Similar results were obtained with endothelium-denuded vessels. 14,15-DHET was released from both the luminal and adventitial surfaces of the HSV. When HSVs were incubated with 14,15-[3H]EET under static (no flow) conditions, formation of 14,15-DHET was detected within 15 min and was inhibited by the selective sEH inhibitors N,N'-dicyclohexyl urea and N-cyclohexyl-N'-dodecanoic acid urea (CUDA). Similarly, CUDA inhibited the conversion of 11,12-[3H]EET to 11,12-DHET by the HSV. sEH inhibition enhanced the uptake of 14,15-[3H]EET and facilitated the formation of 10,11-epoxy-16:2, a beta-oxidation product. The HCA and HA converted 14,15-[3H]EET to DHET, and this also was inhibited by CUDA. These findings in intact human blood vessels indicate that conversion to DHET is the predominant pathway for 11,12- and 14,15-EET metabolism and that sEH inhibition can modulate EET metabolism in vascular tissue.
Collapse
MESH Headings
- 8,11,14-Eicosatrienoic Acid/analogs & derivatives
- 8,11,14-Eicosatrienoic Acid/pharmacology
- Cells, Cultured
- Cyclohexanes/pharmacology
- Endothelium, Vascular/cytology
- Endothelium, Vascular/metabolism
- Epoxide Hydrolases/antagonists & inhibitors
- Epoxide Hydrolases/metabolism
- Epoxy Compounds/metabolism
- Humans
- Hydroxyeicosatetraenoic Acids/pharmacokinetics
- Lauric Acids/pharmacology
- Lipid Metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/metabolism
- Oxidation-Reduction
- Saphenous Vein/drug effects
- Saphenous Vein/enzymology
- Solubility
- Tritium
- Vasodilator Agents/pharmacology
Collapse
Affiliation(s)
- Xiang Fang
- Dept. of Biochemistry, 4-403 BSB, Univ. of Iowa College of Medicine, Iowa City, IA 52242, USA.
| | | | | | | | | | | | | | | |
Collapse
|
6
|
Wang H, Zhao Y, Bradbury JA, Graves JP, Foley J, Blaisdell JA, Goldstein JA, Zeldin DC. Cloning, Expression, and Characterization of Three New Mouse Cytochrome P450 Enzymes and Partial Characterization of Their Fatty Acid Oxidation Activities. Mol Pharmacol 2004; 65:1148-58. [PMID: 15102943 DOI: 10.1124/mol.65.5.1148] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The mammalian CYP2C subfamily is one of the largest and most complicated in the cytochrome P450 superfamily. In this report, we describe the organization of the mouse Cyp2c locus, which contains 15 genes and four pseudogenes, all of which are located in a 5.5-megabase region on chromosome 19. We cloned three novel mouse CYP2C cDNAs (designated CYP2C50, CYP2C54, and CYP2C55) from mouse heart, liver, and colon, respectively. All three cDNAs contain open reading frames that encode 490 amino acid polypeptides that are 57 to 95% identical to other CYP2Cs. The recombinant CYP2C proteins were expressed in Escherichia coli after N-terminal modification, partially purified, and shown to be active in the metabolism of both arachidonic acid (AA) and linoleic acid, albeit with different catalytic efficiencies and profiles. CYP2C50 and CYP2C54 metabolize AA to epoxyeicosatrienoic acids (EETs) primarily, and linoleic acid to epoxyoctadecenoic acids (EOAs) primarily, whereas CYP2C55 metabolizes AA to EETs and hydroxyeicosatetraenoic acids and linoleic acid to EOAs and hydroxyoctadecadienoic acids. Northern blotting and reverse transcription-polymerase chain reaction analysis reveal that CYP2C50 transcripts are abundant in liver and heart; CYP2C54 transcripts are present in liver, kidney, and stomach; and CYP2C55 transcripts are abundant in liver, colon, and kidney. Immunoblotting studies demonstrate that CYP2C50 protein is expressed in liver and heart, CYP2C54 protein is detected primarily in liver, and CYP2C55 protein is present primarily in colon. Immunohistochemistry reveals that CYP2C55 is most abundant in surface columnar epithelium in the cecum. We conclude that these new CYP2C enzymes are probably involved in AA and linoleic acid metabolism in mouse hepatic and extrahepatic tissues.
Collapse
Affiliation(s)
- Hong Wang
- Laboratories of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA
| | | | | | | | | | | | | | | |
Collapse
|
7
|
Granville DJ, Tashakkor B, Takeuchi C, Gustafsson AB, Huang C, Sayen MR, Wentworth P, Yeager M, Gottlieb RA. Reduction of ischemia and reperfusion-induced myocardial damage by cytochrome P450 inhibitors. Proc Natl Acad Sci U S A 2004; 101:1321-6. [PMID: 14734800 PMCID: PMC337051 DOI: 10.1073/pnas.0308185100] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Ischemia and reperfusion both contribute to tissue damage after myocardial infarction. Although many drugs have been shown to reduce infarct size when administered before ischemia, few have been shown to be effective when administered at reperfusion. Moreover, although it is generally accepted that a burst of reactive oxygen species (ROS) occurs at the onset of reperfusion and contributes to tissue damage, the source of ROS and the mechanism of injury is unclear. We now report the finding that chloramphenicol administered at reperfusion reduced infarct size by 60% in a Langendorff isolated perfused rat heart model, and that ROS production was also substantially reduced. Chloramphenicol is an inhibitor of mitochondrial protein synthesis and is also an inhibitor of a subset of cytochrome P450 monooxygenases (CYPs). We could not detect any effect on mitochondrial encoded proteins or mitochondrial respiration in chloramphenicol-perfused hearts, and hypothesized that the effect was caused by inhibition of CYPs. We tested additional CYP inhibitors and found that cimetidine and sulfaphenazole, two CYP inhibitors that have no effect on mitochondrial protein synthesis, were also able to reduce creatine kinase release and infarct size in the Langendorff model. We also showed that chloramphenicol reduced infarct size in an open chest rabbit model of regional ischemia. Taken together, these findings implicate CYPs in myocardial ischemia/reperfusion injury.
Collapse
Affiliation(s)
- David J Granville
- Departments of Molecular and Experimental Medicine, Cell Biology, Chemistry, and Immunology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Abstract
While attention has historically focused on mitochondria as the primary source of ROS in myocardial ischemia/reperfusion injury, recent evidence has implicated cytochrome P450 monooxygenases (CYPs) as a significant factor. CYPs represent a large family of enzymes that catalyze the oxidation of endogenous and exogenous compounds. They catalyze arachidonic acid oxidation to a variety of biologically active eicosanoids that regulate ion channels and protein kinases, with effects on vasomotor tone and cardiac inotropy. They also represent a significant source of reactive oxygen species that may target cellular homeostatic mechanisms and mitochondria. In this review, we will consider the contribution of cytochrome P450 enzymes to reperfusion injury and will speculate on whether the mechanism of injury is due to CYP-mediated ROS production or arachidonic acid metabolites.
Collapse
Affiliation(s)
- Roberta A Gottlieb
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, 10550 N. Torrey Pines Road MEM220, La Jolla, CA 92037, USA.
| |
Collapse
|
9
|
Fang X, Weintraub NL, Oltman CL, Stoll LL, Kaduce TL, Harmon S, Dellsperger KC, Morisseau C, Hammock BD, Spector AA. Human coronary endothelial cells convert 14,15-EET to a biologically active chain-shortened epoxide. Am J Physiol Heart Circ Physiol 2002; 283:H2306-14. [PMID: 12388281 DOI: 10.1152/ajpheart.00448.2002] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cytochrome P-450 epoxygenase-derived epoxyeicosatrienoic acids (EETs) play an important role in the regulation of vascular reactivity and function. Conversion to the corresponding dihydroxyeicosatrienoic acids (DHETs) by soluble epoxide hydrolases is thought to be the major pathway of EET metabolism in mammalian vascular cells. However, when human coronary artery endothelial cells (HCEC) were incubated with (3)H-labeled 14,15-EET, chain-shortened epoxy fatty acids, rather than DHET, were the most abundant metabolites. After 4 h of incubation, 23% of the total radioactivity remaining in the medium was converted to 10,11-epoxy-hexadecadienoic acid (16:2), a product formed from 14,15-EET by two cycles of beta-oxidation, whereas only 15% was present as 14,15-DHET. Although abundantly present in the medium, 10,11-epoxy-16:2 was not detected in the cell lipids. Exogenously applied (3)H-labeled 10,11-epoxy-16:2 was neither metabolized nor retained in the cells, suggesting that 10,11-epoxy-16:2 is a major product of 14,15-EET metabolism in HCEC. 10,11-Epoxy-16:2 produced potent dilation in coronary microvessels. 10,11-Epoxy-16:2 also potently inhibited tumor necrosis factor-alpha-induced production of IL-8, a proinflammatory cytokine, by HCEC. These findings implicate beta-oxidation as a major pathway of 14,15-EET metabolism in HCEC and provide the first evidence that EET-derived chain-shortened epoxy fatty acids are biologically active.
Collapse
MESH Headings
- 8,11,14-Eicosatrienoic Acid/analogs & derivatives
- 8,11,14-Eicosatrienoic Acid/chemistry
- 8,11,14-Eicosatrienoic Acid/metabolism
- Cell Line
- Chromatography, Liquid
- Coronary Vessels/cytology
- Coronary Vessels/drug effects
- Coronary Vessels/physiology
- Culture Media, Conditioned/chemistry
- Endothelium, Vascular/chemistry
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Epoxy Compounds/chemistry
- Epoxy Compounds/metabolism
- Epoxy Compounds/pharmacology
- Fatty Acids, Unsaturated/biosynthesis
- Fatty Acids, Unsaturated/chemistry
- Fatty Acids, Unsaturated/pharmacology
- Humans
- Interleukin-8/biosynthesis
- Mass Spectrometry
- Oxidation-Reduction
- Tumor Necrosis Factor-alpha/pharmacology
- Vasodilator Agents/metabolism
- Vasodilator Agents/pharmacology
Collapse
Affiliation(s)
- Xiang Fang
- Department of Biochemistry, University of Iowa, Iowa City 52242, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Abstract
Epidemiology has implicated dietary fat in mortality associated with some of the most common forms of cancer, including those affecting the intestinal tract, breast and prostate. Polyunsaturated fatty acids, and arachidonate in particular, have been unequivocally linked to experimental colorectal carcinogenesis. Dietary, pharmacologic and genetic manipulation of tissue arachidonic acid and its conversion to bioactive lipids has provided insights into pathogenic mechanisms as well as compelling evidence to support rational preventative and therapeutic methods of disease intervention. While it is clear that conversion of arachidonate to prostaglandins and other bioactive lipids contributes significantly to tumorigenesis in the intestinal tract and other organs, it is also clear that no single metabolic pathway or lipid in this complex biochemical network is solely responsible for dietary or pharmacologic benefits evident in epidemiologic studies. We will review some of these data and provide a summary of our own work showing that conversion of arachidonate to prostaglandin E2 contributes significantly to tumor growth through the modulation of apoptosis and cellular proliferation.
Collapse
Affiliation(s)
- M F McEntee
- Department of Pathology, College of Veterinary Medicine, Institute of Agriculture, University of Tennessee, Knoxville 37996-4542, USA.
| | | |
Collapse
|
11
|
Kanda N, Watanabe S. Ketoconazole suppresses prostaglandin E(2)-induced cyclooxygenase-2 expression in human epidermoid carcinoma A-431 cells. J Invest Dermatol 2002; 119:174-81. [PMID: 12164941 DOI: 10.1046/j.1523-1747.2002.01804.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Cyclooxygenase-2 is a key enzyme in the conversion of arachidonic acid to prostaglandins. The overexpression of cyclooxygenase-2 has been reported in skin cancer cells, and may be involved in carcinogenesis. Prostaglandin E2, the end product of cyclooxygenase-2-induced catalysis, autoamplifies the cyclooxygenase-2 expression. It is suggested that an anti-mycotic drug, ketoconazole may inhibit carcinogenesis. We herein investigated if ketoconazole may inhibit prostaglandin E2-induced cyclooxygenase-2 expression in human epidermoid carcinoma A-431 cells. Ketoconazole suppressed prostaglandin E2-induced cyclooxygenase-2 protein and mRNA expression and promoter activation in A-431; the suppressive effects of ketoconazole were counteracted by cyclic adenosine monophosphate analog. Analyses using deleted or mutated cyclooxygenase-2 promoters revealed that cyclic adenosine monophosphate response element (- 59 to - 53 bp) on the promoter was involved in prostaglandin E2-induced stimulation and ketoconazole-induced inhibition of the promoter activity. Electrophoretic mobility shift assays indicated that cyclic adenosine monophosphate response element binding protein and activating transcription factor-1 may constitutively bind to cyclic adenosine monophosphate response element on cyclooxygenase-2 promoter. Prostaglandin E2 increased the proportion of phosphorylated forms among total bound cyclic adenosine monophosphate response element binding protein/activating transcription factor-1, and the effect was suppressed by ketoconazole. Prostaglandin E2 induced the phosphorylation of cyclic adenosine monophosphate response element binding protein and activating transcription factor-1, and the phosphorylation was suppressed by cyclic adenosine monophosphate-dependent protein kinase (protein kinase A) inhibitor, indicating protein kinase A-mediated phosphorylation. Ketoconazole suppressed the prostaglandin E2-induced phosphorylation of cyclic adenosine monophosphate response element binding protein/activating transcription factor-1. Prostaglandin E2 increased intracellular cyclic adenosine monophosphate level by activating adenylate cyclase in A-431, and the increase was suppressed by ketoconazole. These results suggest that ketoconazole may suppress prostaglandin E2-induced cyclooxygenase-2 expression by inhibiting the cyclic adenosine monophosphate signal in A-431, and stress its anti-cancer effect.
Collapse
Affiliation(s)
- Naoko Kanda
- Department of Dermatology, Teikyo University, School of Medicine, 11-1 Kaga-2, Itabashi-Ku, Tokyo 173-8605, Japan.
| | | |
Collapse
|
12
|
Falck J, Reddy Y, Haines DC, Reddy KM, Krishna U, Graham S, Murry B, Peterson JA. Practical, enantiospecific syntheses of 14,15-EET and leukotoxin B (vernolic acid). Tetrahedron Lett 2001. [DOI: 10.1016/s0040-4039(01)00694-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
13
|
Affiliation(s)
- J R Lupton
- Faculty of Nutrition, Texas A&M University, College Station, Texas 77843-2471, USA.
| |
Collapse
|
14
|
Cytochrome P450 and arachidonic acid bioactivation: molecular and functional properties of the arachidonate monooxygenase. J Lipid Res 2000. [DOI: 10.1016/s0022-2275(20)32049-6] [Citation(s) in RCA: 415] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|
15
|
Boldyrev AA, Carpenter DO, Huentelman MJ, Peters CM, Johnson P. Sources of reactive oxygen species production in excitotoxin- stimulated cerebellar granule cells. Biochem Biophys Res Commun 1999; 256:320-4. [PMID: 10079182 DOI: 10.1006/bbrc.1999.0325] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Reactive oxygen species (ROS) production in rat cerebellar granule cells in the presence of the excitotoxins N-methyl-d-aspartate (NMDA) and kainic acid (KA) and by the protein kinase C activator phorbol myristate acetate (PMA) was Ca2+-dependent and resulted in decreased cell viability. Exposure of stimulated cells to rotenone (a respiratory chain inhibitor) did not decrease ROS levels and did not affect short-term cell viability. In cells stimulated by NMDA and KA, exposure to indomethacin (a cyclooxygenase inhibitor) and nialamide (a monoamine oxidase inhibitor) caused a decrease in ROS levels and increased cell viability occurred in NMDA-treated cells. In contrast, PMA-stimulated neurons did not show decreased ROS levels when exposed to indomethacin and nialamide. These studies suggest that there is a multiplicity of routes for Ca2+-dependent ROS production in neurons but that ROS generation by cyclooxygenase and monoamine oxidase is not controlled by protein kinase C.
Collapse
Affiliation(s)
- A A Boldyrev
- Department of Biochemistry, International Biotechnological Center of M. V. Lomonosov Moscow State University, Moscow, 119899, Russia
| | | | | | | | | |
Collapse
|