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Faraji P, Kühn H, Ahmadian S. Multiple Roles of Apolipoprotein E4 in Oxidative Lipid Metabolism and Ferroptosis During the Pathogenesis of Alzheimer's Disease. J Mol Neurosci 2024; 74:62. [PMID: 38958788 PMCID: PMC11222241 DOI: 10.1007/s12031-024-02224-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 04/14/2024] [Indexed: 07/04/2024]
Abstract
Alzheimer's disease (AD) is the most prevalent neurodegenerative disease worldwide and has a great socio-economic impact. Modified oxidative lipid metabolism and dysregulated iron homeostasis have been implicated in the pathogenesis of this disorder, but the detailed pathophysiological mechanisms still remain unclear. Apolipoprotein E (APOE) is a lipid-binding protein that occurs in large quantities in human blood plasma, and a polymorphism of the APOE gene locus has been identified as risk factors for AD. The human genome involves three major APOE alleles (APOE2, APOE3, APOE4), which encode for three subtly distinct apolipoprotein E isoforms (APOE2, APOE3, APOE4). The canonic function of these apolipoproteins is lipid transport in blood and brain, but APOE4 allele carriers have a much higher risk for AD. In fact, about 60% of clinically diagnosed AD patients carry at least one APOE4 allele in their genomes. Although the APOE4 protein has been implicated in pathophysiological key processes of AD, such as extracellular beta-amyloid (Aβ) aggregation, mitochondrial dysfunction, neuroinflammation, formation of neurofibrillary tangles, modified oxidative lipid metabolism, and ferroptotic cell death, the underlying molecular mechanisms are still not well understood. As for all mammalian cells, iron plays a crucial role in neuronal functions and dysregulation of iron homeostasis has also been implicated in the pathogenesis of AD. Imbalances in iron homeostasis and impairment of the hydroperoxy lipid-reducing capacity induce cellular dysfunction leading to neuronal ferroptosis. In this review, we summarize the current knowledge on APOE4-related oxidative lipid metabolism and the potential role of ferroptosis in the pathogenesis of AD. Pharmacological interference with these processes might offer innovative strategies for therapeutic interventions.
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Affiliation(s)
- Parisa Faraji
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
- Department of Biochemistry, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Hartmut Kühn
- Department of Biochemistry, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany.
| | - Shahin Ahmadian
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.
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Kakularam KR, Canyelles-Niño M, Chen X, Lluch JM, González-Lafont À, Kuhn H. Functional Characterization of Mouse and Human Arachidonic Acid Lipoxygenase 15B (ALOX15B) Orthologs and of Their Mutants Exhibiting Humanized and Murinized Reaction Specificities. Int J Mol Sci 2023; 24:10046. [PMID: 37373195 DOI: 10.3390/ijms241210046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 06/06/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023] Open
Abstract
The arachidonic acid lipoxygenase 15B (ALOX15B) orthologs of men and mice form different reaction products when arachidonic acid is used as the substrate. Tyr603Asp+His604Val double mutation in mouse arachidonic acid lipoxygenase 15b humanized the product pattern and an inverse mutagenesis strategy murinized the specificity of the human enzyme. As the mechanistic basis for these functional differences, an inverse substrate binding at the active site of the enzymes has been suggested, but experimental proof for this hypothesis is still pending. Here we expressed wildtype mouse and human arachidonic acid lipoxygenase 15B orthologs as well as their humanized and murinized double mutants as recombinant proteins and analyzed the product patterns of these enzymes with different polyenoic fatty acids. In addition, in silico substrate docking studies and molecular dynamics simulation were performed to explore the mechanistic basis for the distinct reaction specificities of the different enzyme variants. Wildtype human arachidonic acid lipoxygenase 15B converted arachidonic acid and eicosapentaenoic acid to their 15-hydroperoxy derivatives but the Asp602Tyr+Val603His exchange murinized the product pattern. The inverse mutagenesis strategy in mouse arachidonic acid lipoxygenase 15b (Tyr603Asp+His604Val exchange) humanized the product pattern with these substrates, but the situation was different with docosahexaenoic acid. Here, Tyr603Asp+His604Val substitution in mouse arachidonic acid lipoxygenase 15b also humanized the specificity but the inverse mutagenesis (Asp602Tyr+Val603His) did not murinize the human enzyme. With linoleic acid Tyr603Asp+His604Val substitution in mouse arachidonic acid lipoxygenase 15b humanized the product pattern but the inverse mutagenesis in human arachidonic acid lipoxygenase 15B induced racemic product formation. Amino acid exchanges at critical positions of human and mouse arachidonic acid lipoxygenase 15B orthologs humanized/murinized the product pattern with C20 fatty acids, but this was not the case with fatty acid substrates of different chain lengths. Asp602Tyr+Val603His exchange murinized the product pattern of human arachidonic acid lipoxygenase 15B with arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid. An inverse mutagenesis strategy on mouse arachidonic acid lipoxygenase 15b (Tyr603Asp+His604Val exchange) did humanize the reaction products with arachidonic acid and eicosapentaenoic acid, but not with docosahexaenoic acid.
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Affiliation(s)
- Kumar R Kakularam
- Department of Biochemistry, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität zu Berlin, D-10117 Berlin, Germany
| | - Miquel Canyelles-Niño
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
- Arquebio S.L., 08005 Barcelona, Spain
| | - Xin Chen
- Department of Biochemistry, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität zu Berlin, D-10117 Berlin, Germany
| | - José M Lluch
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
- Institut de Biotecnologia i de Biomedicina (IBB), Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Àngels González-Lafont
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
- Institut de Biotecnologia i de Biomedicina (IBB), Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Hartmut Kuhn
- Department of Biochemistry, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität zu Berlin, D-10117 Berlin, Germany
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Functional Characterization of Novel Bony Fish Lipoxygenase Isoforms and Their Possible Involvement in Inflammation. Int J Mol Sci 2022; 23:ijms232416026. [PMID: 36555666 PMCID: PMC9787790 DOI: 10.3390/ijms232416026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 12/10/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
Eicosanoids and related compounds are pleiotropic lipid mediators, which are biosynthesized in mammals via three distinct metabolic pathways (cyclooxygenase pathway, lipoxygenase pathway, epoxygenase pathway). These mediators have been implicated in the pathogenesis of inflammatory diseases and drugs interfering with eicosanoid signaling are currently available as antiphlogistics. Eicosanoid biosynthesis has well been explored in mammals including men, but much less detailed information is currently available on eicosanoid biosynthesis in other vertebrates including bony fish. There are a few reports in the literature describing the expression of arachidonic acid lipoxygenases (ALOX isoforms) in several bony fish species but except for two zebrafish ALOX-isoforms (zfALOX1 and zfALOX2) bony fish eicosanoid biosynthesizing enzymes have not been characterized. To fill this gap and to explore the possible roles of ALOX15 orthologs in bony fish inflammation we cloned and expressed putative ALOX15 orthologs from three different bony fish species (N. furzeri, P. nyererei, S. formosus) as recombinant N-terminal his-tag fusion proteins and characterized the corresponding enzymes with respect to their catalytic properties (temperature-dependence, activation energy, pH-dependence, substrate affinity and substrate specificity with different polyenoic fatty acids). Furthermore, we identified the chemical structure of the dominant oxygenation products formed by the recombinant enzymes from different free fatty acids and from more complex lipid substrates. Taken together, our data indicate that functional ALOX isoforms occur in bony fish but that their catalytic properties are different from those of mammalian enzymes. The possible roles of these ALOX-isoforms in bony fish inflammation are discussed.
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Blunder S, Pavel P, Minzaghi D, Dubrac S. PPARdelta in Affected Atopic Dermatitis and Psoriasis: A Possible Role in Metabolic Reprograming. Int J Mol Sci 2021; 22:7354. [PMID: 34298981 PMCID: PMC8303290 DOI: 10.3390/ijms22147354] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/06/2021] [Accepted: 07/07/2021] [Indexed: 12/16/2022] Open
Abstract
Peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors expressed in the skin. Three PPAR isotypes, α (NRC1C1), β or δ (NRC1C2) and γ (NRC1C3), have been identified. After activation through ligand binding, PPARs heterodimerize with the 9-cis-retinoic acid receptor (RXR), another nuclear hormone receptor, to bind to specific PPAR-responsive elements in regulatory regions of target genes mainly involved in organogenesis, cell proliferation, cell differentiation, inflammation and metabolism of lipids or carbohydrates. Endogenous PPAR ligands are fatty acids and fatty acid metabolites. In past years, much emphasis has been given to PPARα and γ in skin diseases. PPARβ/δ is the least studied PPAR family member in the skin despite its key role in several important pathways regulating inflammation, keratinocyte proliferation and differentiation, metabolism and the oxidative stress response. This review focuses on the role of PPARβ/δ in keratinocytes and its involvement in psoriasis and atopic dermatitis. Moreover, the relevance of targeting PPARβ/δ to alleviate skin inflammation is discussed.
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Affiliation(s)
| | | | | | - Sandrine Dubrac
- Epidermal Biology Laboratory, Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, Anichstraße 35, 6020 Innsbruck, Austria; (S.B.); (P.P.); (D.M.)
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Zhuravlev A, Golovanov A, Toporkov V, Kuhn H, Ivanov I. Functionalized Homologues and Positional Isomers of Rabbit 15-Lipoxygenase RS75091 Inhibitor. Med Chem 2021; 18:406-416. [PMID: 34097594 DOI: 10.2174/1573406417666210604112009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 03/12/2021] [Accepted: 04/05/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND RS75091 is a cinnamic acid derivative that has been used for the crystallization of the rabbit ALOX15-inhibitor complex. The atomic coordinates of the resolved ALOX15-inhibitor complex were later used to define the binding sites of other mammalian lipoxygenase orthologs, for which no direct structural data with ligand has been reported so far. INTRODUCTION The putative binding pocket of the human ALOX5 was reconstructed on the basis of its structural alignment with rabbit ALOX15-RS75091 inhibitor. However, considering the possible conformational changes the enzyme may undergo in solution, it remains unclear whether the existing models adequately mirror the architecture of the ALOX5 active site. METHODS In this study, we prepared a series of RS75091 derivatives using a Sonogashira coupling reaction of regioisomeric bromocinnamates with protected acetylenic alcohols and tested their inhibitory properties on rabbit ALOX15. RESULTS A bulky pentafluorophenyl moiety linked to either ortho- or metha-ethynylcinnamates via aliphatic spacer does not significantly impair the inhibitory properties of RS75091. CONCLUSION Hydroxylated 2- and 3-alkynylcinnamates may be suitable candidates for incorporation of an aromatic linker group like tetrafluorophenylazides for photoaffinity labeling assays.
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Affiliation(s)
- Alexander Zhuravlev
- Lomonosov Institute of Fine Chemical Technologies, MIREA - Russian Technological University, Vernadskogo pr. 86, 119571 Moscow. Russian Federation
| | - Alexey Golovanov
- Lomonosov Institute of Fine Chemical Technologies, MIREA - Russian Technological University, Vernadskogo pr. 86, 119571 Moscow. Russian Federation
| | - Valery Toporkov
- Lomonosov Institute of Fine Chemical Technologies, MIREA - Russian Technological University, Vernadskogo pr. 86, 119571 Moscow. Russian Federation
| | - Hartmut Kuhn
- Institute of Biochemistry, Charite - University Medicine Berlin, Corporate member of Free University Berlin, Humboldt University Berlin and Berlin Institute of Health, Charitéplatz 1, D-10117 Berlin. Germany
| | - Igor Ivanov
- Lomonosov Institute of Fine Chemical Technologies, MIREA - Russian Technological University, Vernadskogo pr. 86, 119571 Moscow. Russian Federation
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Mori Y, Kawakami Y, Kanzaki K, Otsuki A, Kimura Y, Kanji H, Tanaka R, Tsukayama I, Hojo N, Suzuki-Yamamoto T, Kawakami T, Takahashi Y. Arachidonate 12S-lipoxygenase of platelet-type in hepatic stellate cells of methionine and choline-deficient diet-fed mice. J Biochem 2021; 168:455-463. [PMID: 32492133 DOI: 10.1093/jb/mvaa062] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 05/22/2020] [Indexed: 02/06/2023] Open
Abstract
A role of 12-lipoxygenase in the progression of non-alcoholic steatohepatitis (NASH) is suggested, although the underlying mechanism is not entirely understood. The catalytic activity of 12S-lipoxygenase that was hardly observed in liver cytosol of normal chow-fed mice was clearly detectable in that of NASH model mice prepared by feeding a methionine and choline-deficient (MCD) diet. The product profile, substrate specificity and immunogenicity indicated that the enzyme was the platelet-type isoform. The expression levels of mRNA and protein of platelet-type 12S-lipoxygenase in the liver of MCD diet-fed mice were significantly increased compared with those of normal chow-fed mice. Immunohistochemical analysis showed that platelet-type 12S-lipoxygenase colocalized with α-smooth muscle actin as well as vitamin A in the cells distributing along liver sinusoids. These results indicate that the expression level of platelet-type 12S-lipoxygenase in hepatic stellate cells was increased during the cell activation in MCD diet-fed mice, suggesting a possible role of the enzyme in pathophysiology of liver fibrosis.
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Affiliation(s)
- Yoshiko Mori
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197, Japan
| | - Yuki Kawakami
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197, Japan
| | - Keita Kanzaki
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197, Japan.,Department of Clinical Nutrition, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, 288 Matsushima, Kurashiki, Okayama 701-0193, Japan
| | - Akemi Otsuki
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197, Japan
| | - Yuka Kimura
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197, Japan
| | - Hibiki Kanji
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197, Japan
| | - Ryoma Tanaka
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197, Japan
| | - Izumi Tsukayama
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197, Japan
| | - Nana Hojo
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197, Japan
| | - Toshiko Suzuki-Yamamoto
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197, Japan
| | - Takayo Kawakami
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197, Japan
| | - Yoshitaka Takahashi
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197, Japan
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Flitter BA, Fang X, Matthay MA, Gronert K. The potential of lipid mediator networks as ocular surface therapeutics and biomarkers. Ocul Surf 2021; 19:104-114. [PMID: 32360792 PMCID: PMC7606340 DOI: 10.1016/j.jtos.2020.04.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 04/10/2020] [Accepted: 04/12/2020] [Indexed: 01/03/2023]
Abstract
In the last twenty years an impressive body of evidence in diverse inflammatory animal disease models and human tissues, has established polyunsaturated fatty acids (PUFA) derived specialized-pro-resolving mediators (SPM), as essential mediators for controlling acute inflammation, immune responses, wound healing and for resolving acute inflammation in many non-ocular tissues. SPM pathways and receptors are highly expressed in the ocular surface where they regulate wound healing, nerve regeneration, innate immunity and sex-specific regulation of auto-immune responses. Recent evidence indicates that in the eye these resident SPM networks are important for maintaining ocular surface health and immune homeostasis. Here, we will review and discuss evidence for SPMs and other PUFA-derived mediators as important endogenous regulators, biomarkers for ocular surface health and disease and their therapeutic potential.
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Affiliation(s)
- Becca A Flitter
- School of Optometry, University of California Berkeley, Berkeley, CA, 94720, USA; Vision Science Program, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Xiaohui Fang
- Department of Medicine and Anesthesia, University of California, San Francisco, CA, USA; Cardiovascular Research Institute, University of California, San Francisco, CA, USA
| | - Michael A Matthay
- Department of Medicine and Anesthesia, University of California, San Francisco, CA, USA; Cardiovascular Research Institute, University of California, San Francisco, CA, USA
| | - Karsten Gronert
- School of Optometry, University of California Berkeley, Berkeley, CA, 94720, USA; Vision Science Program, University of California Berkeley, Berkeley, CA, 94720, USA; Infectious Diseases and Immunity Program, University of California Berkeley, Berkeley, CA, 94720, USA.
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Rademacher M, Kuhn H, Borchert A. Systemic deficiency of mouse arachidonate 15-lipoxygenase induces defective erythropoiesis and transgenic expression of the human enzyme rescues this phenotype. FASEB J 2020; 34:14318-14335. [PMID: 32918502 DOI: 10.1096/fj.202000408rr] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 07/29/2020] [Accepted: 08/07/2020] [Indexed: 02/06/2023]
Abstract
Arachidonic acid 15-lipoxygenases (ALOX15) are lipid peroxidizing enzymes, which has previously been implicated in the maturational breakdown of intracellular organelles and plasma membrane remodeling during reticulocyte-erythrocyte transition. Conventional Alox15-/- mice are viable, develop normally but do not exhibit a major defective erythropoietic phenotype. To characterize the putative in vivo relevance of Alox15 for red blood cell development, we explored the impact of systemic inactivation of the Alox15 gene on mouse erythropoiesis. We found that Alox15-/- mice exhibited reduced erythrocyte counts, elevated reticulocyte counts and red cell hyperchromia. The structure of the plasma membrane of Alox15-/- erythrocytes is altered and a significant share of the red cells was present as echinocytes and/or acanthocytes. An increased share of the Alox15-/- erythrocytes cells were annexin V positive, which indicates a loss of plasma membrane asymmetry. Erythrocytes of Alox15-/- mice were more susceptible to osmotic hemolysis and exhibited a reduced ex vivo life span. When we transgenically expressed human ALOX15 in Alox15-/- mice under the control of the aP2 promoter the defective erythropoietic system was rescued and the impaired osmotic resistance was normalized. Together these data suggest the involvement Alox15 in the maturational remodeling of the plasma membrane during red cell development.
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Affiliation(s)
- Marlena Rademacher
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Biochemistry, Berlin, Germany
| | - Hartmut Kuhn
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Biochemistry, Berlin, Germany
| | - Astrid Borchert
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Biochemistry, Berlin, Germany
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Biringer RG. The enzymology of human eicosanoid pathways: the lipoxygenase branches. Mol Biol Rep 2020; 47:7189-7207. [PMID: 32748021 DOI: 10.1007/s11033-020-05698-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 07/26/2020] [Indexed: 12/16/2022]
Abstract
Eicosanoids are short-lived derivatives of polyunsaturated fatty acids that serve as autocrine and paracrine signaling molecules. They are involved numerous biological processes of both the well state and disease states. A thorough understanding of the progression the disease state and homeostasis of the well state requires a complete evaluation of the systems involved. This review examines the enzymology for the enzymes involved in the production of eicosanoids along the lipoxygenase branches of the eicosanoid pathways with particular emphasis on those derived from arachidonic acid. The enzymatic parameters, protocols to measure them, and proposed catalytic mechanisms are presented in detail.
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Affiliation(s)
- Roger Gregory Biringer
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, Bradenton, FL, 34211, USA.
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10
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Reisch F, Kakularam KR, Stehling S, Heydeck D, Kuhn H. Eicosanoid biosynthesis in marine mammals. FEBS J 2020; 288:1387-1406. [PMID: 32627384 DOI: 10.1111/febs.15469] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 05/19/2020] [Accepted: 06/22/2020] [Indexed: 01/09/2023]
Abstract
After 300 million years of evolution, the first land-living mammals reentered the marine environment some 50 million years ago. The driving forces for this dramatic lifestyle change are still a matter of discussion but the struggle for food resources and the opportunity to escape predators probably contributed. Reentering the oceans requires metabolic adaption putting evolutionary pressure on a number of genes. To explore whether eicosanoid signaling has been part of this adaptive response, we first explored whether the genomes of marine mammals involve functional genes encoding for key enzymes of eicosanoid biosynthesis. Cyclooxygenase (COX) and lipoxygenase (ALOX) genes are present in the genome of all marine mammals tested. Interestingly, ALOX12B, which has been implicated in skin development of land-living mammals, is lacking in whales and dolphins and genes encoding for its sister enzyme (ALOXE3) involve premature stop codons and/or frameshifting point mutations, which interrupt the open reading frames. ALOX15 orthologs have been detected in all marine mammals, and the recombinant enzymes exhibit similar catalytic properties as those of land-living species. All marine mammals express arachidonic acid 12-lipoxygenating ALOX15 orthologs, and these data are consistent with the Evolutionary Hypothesis of ALOX15 specificity. These enzymes exhibit membrane oxygenase activity and introduction of big amino acids at the triad positions altered the reaction specificity in favor of arachidonic acid 15-lipoxygenation. Thus, the ALOX15 orthologs of marine mammals follow the Triad concept explaining their catalytic specificity.
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Affiliation(s)
- Florian Reisch
- Institute of Biochemistry, Charité - University Medicine Berlin, Corporate member of Free University Berlin, Humboldt University Berlin and Berlin Institute of Health, Berlin, Germany
| | - Kumar Reddy Kakularam
- Institute of Biochemistry, Charité - University Medicine Berlin, Corporate member of Free University Berlin, Humboldt University Berlin and Berlin Institute of Health, Berlin, Germany
| | - Sabine Stehling
- Institute of Biochemistry, Charité - University Medicine Berlin, Corporate member of Free University Berlin, Humboldt University Berlin and Berlin Institute of Health, Berlin, Germany
| | - Dagmar Heydeck
- Institute of Biochemistry, Charité - University Medicine Berlin, Corporate member of Free University Berlin, Humboldt University Berlin and Berlin Institute of Health, Berlin, Germany
| | - Hartmut Kuhn
- Institute of Biochemistry, Charité - University Medicine Berlin, Corporate member of Free University Berlin, Humboldt University Berlin and Berlin Institute of Health, Berlin, Germany
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11
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Kuhn H, Humeniuk L, Kozlov N, Roigas S, Adel S, Heydeck D. The evolutionary hypothesis of reaction specificity of mammalian ALOX15 orthologs. Prog Lipid Res 2018; 72:55-74. [PMID: 30237084 DOI: 10.1016/j.plipres.2018.09.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 09/04/2018] [Accepted: 09/13/2018] [Indexed: 02/07/2023]
Affiliation(s)
- Hartmut Kuhn
- Charité - Universitätsmedizin Berlin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Biochemistry, Charitéplatz 1, CCO- Building, Virchowweg 6, D-10117 Berlin, Germany.
| | - Lia Humeniuk
- Charité - Universitätsmedizin Berlin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Biochemistry, Charitéplatz 1, CCO- Building, Virchowweg 6, D-10117 Berlin, Germany
| | - Nikita Kozlov
- Charité - Universitätsmedizin Berlin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Biochemistry, Charitéplatz 1, CCO- Building, Virchowweg 6, D-10117 Berlin, Germany
| | - Sophie Roigas
- Charité - Universitätsmedizin Berlin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Biochemistry, Charitéplatz 1, CCO- Building, Virchowweg 6, D-10117 Berlin, Germany
| | - Susan Adel
- Charité - Universitätsmedizin Berlin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Internal Medicine, Division of Hepathology and Gastroenterology, Augustenburger Platz 1, D-13353 Berlin, Germany
| | - Dagmar Heydeck
- Charité - Universitätsmedizin Berlin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Biochemistry, Charitéplatz 1, CCO- Building, Virchowweg 6, D-10117 Berlin, Germany
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12
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Araújo AC, Wheelock CE, Haeggström JZ. The Eicosanoids, Redox-Regulated Lipid Mediators in Immunometabolic Disorders. Antioxid Redox Signal 2018; 29:275-296. [PMID: 28978222 DOI: 10.1089/ars.2017.7332] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
SIGNIFICANCE The oxidation of arachidonic acid via cyclooxygenase (COX) and lipoxygenase (LOX) activity to produce eicosanoids during inflammation is a well-known biosynthetic pathway. These lipid mediators are involved in fever, pain, and thrombosis and are produced from multiple cells as well as cell/cell interactions, for example, immune cells and epithelial/endothelial cells. Metabolic disorders, including hyperlipidemia, hypertension, and diabetes, are linked with chronic low-grade inflammation, impacting the immune system and promoting a variety of chronic diseases. Recent Advances: Multiple studies have corroborated the important function of eicosanoids and their receptors in (non)-inflammatory cells in immunometabolic disorders (e.g., insulin resistance, obesity, and cardiovascular and nonalcoholic fatty liver diseases). In this context, LOX and COX products are involved in both pro- and anti-inflammatory responses. In addition, recent work has elucidated the potent function of specialized proresolving mediators (i.e., lipoxins and resolvins) in resolving inflammation, protecting organs, and stimulating tissue repair and remodeling. CRITICAL ISSUES Inhibiting/stimulating selected eicosanoid pathways may result in anti-inflammatory and proresolution responses leading to multiple beneficial effects, including the abrogation of reactive oxygen species production, increased speed of resolution, and overall improvement of diseases related to immunometabolic perturbations. FUTURE DIRECTIONS Despite many achievements, it is crucial to understand the molecular and cellular mechanisms underlying immunological/metabolic cross talk to offer substantial therapeutic promise. Antioxid. Redox Signal. 29, 275-296.
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Affiliation(s)
- Ana Carolina Araújo
- Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institutet , Stockholm, Sweden
| | - Craig E Wheelock
- Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institutet , Stockholm, Sweden
| | - Jesper Z Haeggström
- Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institutet , Stockholm, Sweden
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Simard-Bisson C, Parent LA, Moulin VJ, Fruteau de Laclos B. Characterization of Epidermal Lipoxygenase Expression in Normal Human Skin and Tissue-Engineered Skin Substitutes. J Histochem Cytochem 2018; 66:813-824. [PMID: 29985723 DOI: 10.1369/0022155418788117] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Lipoxygenases (LOXs) are enzymes likely to be involved in corneocyte lipid envelope formation and skin barrier function. In humans, mutations in epidermis-type lipoxygenase 3 ( eLOX-3) and 12R-lipoxygenase ( 12R-LOX) genes are associated with autosomal recessive congenital ichthyosis (ARCI), whereas deletion of these genes in mice causes epidermal defects. LOXs also represent a matter of interest in psoriasis as well as in cancer research. However, their expression as well as the exact role of these enzymes in normal human skin have not been fully described. Our goal was to characterize the expression of epidermal LOXs in both normal human skin and Tissue-Engineered Skin Substitutes (TESS) and to consider TESS as a potential model for LOX functional studies. Staining for epidermal differentiation markers and LOXs was performed, in parallel, on normal human skin and TESS. Our results showed similar expression profiles in TESS when compared with native skin for e-LOX3, 12R-LOX, 12S-lipoxygenase (12S-LOX), and 15-lipoxygenase 2 (15-LOX-2) but not for 15-lipoxygenase 1 (15-LOX-1). Because of their appropriate epidermal differentiation and LOX expression, TESS represent an alternative model for future studies on LOX function.
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Affiliation(s)
- Carolyne Simard-Bisson
- Centre de recherche du CHU de Québec-Université Laval and Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Quebec City, Québec, Canada
| | - Lorraine Andrée Parent
- Centre de recherche du CHU de Québec-Université Laval and Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Quebec City, Québec, Canada
| | - Véronique J Moulin
- Centre de recherche du CHU de Québec-Université Laval and Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Quebec City, Québec, Canada.,Department of Surgery, Faculty of Medicine, Université Laval, Quebec City, Québec, Canada
| | - Bernard Fruteau de Laclos
- Centre de recherche du CHU de Québec-Université Laval and Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Quebec City, Québec, Canada.,Department of Molecular Biology, Medical Biochemistry and Pathology, Faculty of Medicine, Université Laval, Quebec City, Québec, Canada
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Chien Y, Chou SJ, Chang YL, Leu HB, Yang YP, Tsai PH, Lai YH, Chen KH, Chang WC, Sung SH, Yu WC. Inhibition of Arachidonate 12/15-Lipoxygenase Improves α-Galactosidase Efficacy in iPSC-Derived Cardiomyocytes from Fabry Patients. Int J Mol Sci 2018; 19:ijms19051480. [PMID: 29772700 PMCID: PMC5983630 DOI: 10.3390/ijms19051480] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 05/03/2018] [Accepted: 05/08/2018] [Indexed: 02/07/2023] Open
Abstract
(1) Background: A high incidence of intervening sequence (IVS)4+919 G>A mutation with later-onset cardiac phenotype have been reported in a majority of Taiwan Fabry cohorts. Some evidence indicated that conventional biomarkers failed to predict the long-term progression and therapeutic outcome; (2) Methods: In this study, we constructed an induced pluripotent stem cell (iPSC)-based platform from Fabry cardiomyopathy (FC) patients carrying IVS4+919 G>A mutation to screen for potential targets that may help the conventional treatment; (3) Results: The FC-patient-derived iPSC-differentiated cardiomyocytes (FC-iPSC-CMs) carried an expected IVS4+919 G>A genetic mutation and recapitulated several FC characteristics, including low α-galactosidase A enzyme activity and cellular hypertrophy. The proteomic analysis revealed that arachidonate 12/15-lipoxygenase (Alox12/15) was the most highly upregulated marker in FC-iPSC-CMs, and the metabolites of Alox12/15, 12(S)- and 15(S)-hydroxyeicosatetraenoic acid (HETE), were also elevated in the culture media. Late administration of Alox12/15 pharmacological inhibitor LOXBlock-1 combined with α-galactosidase, but not α-galactosidase alone, effectively reduced cardiomyocyte hypertrophy, the secretion of 12(S)- and 15(S)-HETE and the upregulation of fibrotic markers at the late phase of FC; (4) Conclusions: Our study demonstrates that cardiac Alox12/15 and circulating 12(S)-HETE/15(S)-HETE are involved in the pathogenesis of FC with IVS4+919 G>A mutation.
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Affiliation(s)
- Yueh Chien
- Institute of Pharmacology, School of Medicine, National Yang-Ming University, Taipei 11217, Taiwan.
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan.
| | - Shih-Jie Chou
- Institute of Pharmacology, School of Medicine, National Yang-Ming University, Taipei 11217, Taiwan.
| | - Yuh-Lih Chang
- Institute of Pharmacology, School of Medicine, National Yang-Ming University, Taipei 11217, Taiwan.
- Department of Pharmacology, Taipei Veterans General Hospital, Taipei 11217, Taiwan.
| | - Hsin-Bang Leu
- Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei 11217, Taiwan.
- Heath Care and Management Center, Taipei Veterans General Hospital, Taipei 11217, Taiwan.
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei 11217, Taiwan.
| | - Yi-Ping Yang
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan.
| | - Ping-Hsing Tsai
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan.
- Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei 11217, Taiwan.
| | - Ying-Hsiu Lai
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan.
| | - Kuan-Hsuan Chen
- Department of Pharmacology, Taipei Veterans General Hospital, Taipei 11217, Taiwan.
- Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei 11217, Taiwan.
| | - Wei-Chao Chang
- Center for Molecular Medicine, China Medical University Hospital, Taichung 40447, Taiwan.
| | - Shih-Hsien Sung
- Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei 11217, Taiwan.
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei 11217, Taiwan.
| | - Wen-Chung Yu
- Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei 11217, Taiwan.
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei 11217, Taiwan.
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15
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Rorke EA, Adhikary G, Young CA, Rice RH, Elias PM, Crumrine D, Meyer J, Blumenberg M, Eckert RL. Structural and biochemical changes underlying a keratoderma-like phenotype in mice lacking suprabasal AP1 transcription factor function. Cell Death Dis 2015; 6:e1647. [PMID: 25695600 PMCID: PMC4669787 DOI: 10.1038/cddis.2015.21] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 01/06/2015] [Indexed: 01/07/2023]
Abstract
Epidermal keratinocyte differentiation on the body surface is a carefully choreographed process that leads to assembly of a barrier that is essential for life. Perturbation of keratinocyte differentiation leads to disease. Activator protein 1 (AP1) transcription factors are key controllers of this process. We have shown that inhibiting AP1 transcription factor activity in the suprabasal murine epidermis, by expression of dominant-negative c-jun (TAM67), produces a phenotype type that resembles human keratoderma. However, little is understood regarding the structural and molecular changes that drive this phenotype. In the present study we show that TAM67-positive epidermis displays altered cornified envelope, filaggrin-type keratohyalin granule, keratin filament, desmosome formation and lamellar body secretion leading to reduced barrier integrity. To understand the molecular changes underlying this process, we performed proteomic and RNA array analysis. Proteomic study of the corneocyte cross-linked proteome reveals a reduction in incorporation of cutaneous keratins, filaggrin, filaggrin2, late cornified envelope precursor proteins, hair keratins and hair keratin-associated proteins. This is coupled with increased incorporation of desmosome linker, small proline-rich, S100, transglutaminase and inflammation-associated proteins. Incorporation of most cutaneous keratins (Krt1, Krt5 and Krt10) is reduced, but incorporation of hyperproliferation-associated epidermal keratins (Krt6a, Krt6b and Krt16) is increased. RNA array analysis reveals reduced expression of mRNA encoding differentiation-associated cutaneous keratins, hair keratins and associated proteins, late cornified envelope precursors and filaggrin-related proteins; and increased expression of mRNA encoding small proline-rich proteins, protease inhibitors (serpins), S100 proteins, defensins and hyperproliferation-associated keratins. These findings suggest that AP1 factor inactivation in the suprabasal epidermal layers reduces expression of AP1 factor-responsive genes expressed in late differentiation and is associated with a compensatory increase in expression of early differentiation genes.
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Affiliation(s)
- E A Rorke
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - G Adhikary
- Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - C A Young
- Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - R H Rice
- Department of Environmental Toxicology, University of California, Davis, CA, USA
| | - P M Elias
- Dermatology Service, Veterans Affairs Medical Center, San Francisco and Department of Dermatology, University of California, San Francisco, CA, USA
| | - D Crumrine
- Dermatology Service, Veterans Affairs Medical Center, San Francisco and Department of Dermatology, University of California, San Francisco, CA, USA
| | - J Meyer
- Dermatology Service, Veterans Affairs Medical Center, San Francisco and Department of Dermatology, University of California, San Francisco, CA, USA
| | - M Blumenberg
- The R.O. Perelman Department of Dermatology, Department of Biochemistry and Molecular Pharmacology, New York University Cancer Institute, New York City, NY, USA
| | - R L Eckert
- 1] Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, USA [2] Dermatology, University of Maryland School of Medicine, Baltimore, MD, USA [3] Obstetrics and Gynecology, University of Maryland School of Medicine, Baltimore, MD, USA [4] Greenebaum Cancer Center University of Maryland School of Medicine, Baltimore, MD, USA
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16
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Hong S, Alapure BV, Lu Y, Tian H, Wang Q. 12/15-Lipoxygenase deficiency reduces densities of mesenchymal stem cells in the dermis of wounded and unwounded skin. Br J Dermatol 2014; 171:30-38. [PMID: 24593251 DOI: 10.1111/bjd.12899] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/10/2014] [Indexed: 01/09/2023]
Abstract
BACKGROUND Mesenchymal stem cells (MSCs) promote skin healing. 12/15-Lipoxgenase (LOX) is crucial in producing specific lipid mediators in wounded skin. The consequences of 12/15-LOX deficiency in MSC densities in skin are unknown. OBJECTIVES To determine the effect of 12/15-LOX deficiency in MSC densities in wounded and unwounded dermis. METHODS Full-thickness skin incisional wounds were made to 12/15-LOX-deficient (12/15-LOX(-/-) ) and wild-type (WT) C57BL/6 mice. Wounded skin was collected at 3, 8, or 14 days postwounding (dpw). MSCs were analysed in skin sections using histology. 12S- or 15S-hydroxy-eicosatetraenoic acid (HETE) was analysed using a reversed-phase Chiral liquid chromatography-ultraviolet-tandem mass spectrometer. RESULTS There were more stem cell antigen (Sca)1(+) CD29(+) MSCs (cells/field) at 3, 8, and 14 dpw, more Sca1(+) CD106(+) MSCs at 3 and 14 dpw in the wounded dermis, more MSCs in unwounded dermis of WT mice compared with 12/15-LOX(-/-) mice, and more MSCs in the wounded dermis than in the unwounded dermis. For 12/15-LOX(-/-) dermis, Sca1(+) CD106(+) MSCs peaked and Sca1(+) CD29(+) MSCs reached a flat level at 8 dpw. However, for the WT dermis, MSCs increased from 8 to 14 dpw. There were more Sca1(+) CD106(+) MSCs than Sca1(+) CD29(+) MSCs in the 12/15-LOX(-/-) wounded dermis at 8 dpw. However, there were more Sca1(+) CD29(+) MSCs in the 12/15-LOX(-/-) than Sca1(+) CD106(+) MSCs in the WT wounded dermis at 3 dpw, and Sca1(+) CD106(+) MSCs and Sca1(+) CD29(+) MSCs were at comparable levels in other conditions. 12/15-LOX deficiency suppressed levels of 12/15-LOX protein and their products, 12S-HETE and 15S-HETE, in wounds. CONCLUSIONS 12/15-LOX deficiency reduces MSC densities in the dermis, which correlates with the suppressed 12/15-LOX pathways in wounded and unwounded skin.
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Affiliation(s)
- S Hong
- Center of Neuroscience Excellence, Louisiana State University Health Science Center, New Orleans, LA 70112
| | - B V Alapure
- Center of Neuroscience Excellence, Louisiana State University Health Science Center, New Orleans, LA 70112
| | - Y Lu
- Center of Neuroscience Excellence, Louisiana State University Health Science Center, New Orleans, LA 70112
| | - H Tian
- Center of Neuroscience Excellence, Louisiana State University Health Science Center, New Orleans, LA 70112
| | - Q Wang
- Center of Neuroscience Excellence, Louisiana State University Health Science Center, New Orleans, LA 70112
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17
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Krieg P, Fürstenberger G. The role of lipoxygenases in epidermis. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1841:390-400. [PMID: 23954555 DOI: 10.1016/j.bbalip.2013.08.005] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 07/31/2013] [Accepted: 08/05/2013] [Indexed: 12/11/2022]
Abstract
Lipoxygenases (LOX) are key enzymes in the biosynthesis of a variety of highly active oxylipins which act as signaling molecules involved in the regulation of many biological processes. LOX are also able to oxidize complex lipids and modify membrane structures leading to structural changes that play a role in the maturation and terminal differentiation of various cell types. The mammalian skin represents a tissue with highly abundant and diverse LOX metabolism. Individual LOX isozymes are thought to play a role in the modulation of epithelial proliferation and/or differentiation as well as in inflammation, wound healing, inflammatory skin diseases and cancer. Emerging evidence indicates a structural function of a particular LOX pathway in the maintenance of skin permeability barrier. Loss-of-function mutations in the LOX genes ALOX12B and ALOXE3 have been found to represent the second most common cause of autosomal recessive congenital ichthyosis and targeted disruption of the corresponding LOX genes in mice resulted in neonatal death due to a severely impaired permeability barrier function. Recent data indicate that LOX action in barrier function can be traced back to the oxygenation of linoleate-containing ceramides which constitutes an important step in the formation of the corneocyte lipid envelope. This article is part of a Special Issue entitled The Important Role of Lipids in the Epidermis and their Role in the Formation and Maintenance of the Cutaneous Barrier. Guest Editors: Kenneth R. Feingold and Peter Elias.
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Affiliation(s)
- Peter Krieg
- Genome Modifications and Carcinogenesis, Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, D69120 Heidelberg, Germany.
| | - Gerhard Fürstenberger
- Genome Modifications and Carcinogenesis, Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, D69120 Heidelberg, Germany
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18
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Othman A, Ahmad S, Megyerdi S, Mussell R, Choksi K, Maddipati KR, Elmarakby A, Rizk N, Al-Shabrawey M. 12/15-Lipoxygenase-derived lipid metabolites induce retinal endothelial cell barrier dysfunction: contribution of NADPH oxidase. PLoS One 2013; 8:e57254. [PMID: 23437353 PMCID: PMC3577708 DOI: 10.1371/journal.pone.0057254] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 01/18/2013] [Indexed: 01/08/2023] Open
Abstract
The purpose of the current study was to evaluate the effect of 12/15- lipoxygenase (12/15-LOX) metabolites on retinal endothelial cell (REC) barrier function. FITC-dextran flux across the REC monolayers and electrical cell-substrate impedance sensing (ECIS) were used to evaluate the effect of 12- and 15-hydroxyeicosatetreanoic acids (HETE) on REC permeability and transcellular electrical resistance (TER). Effect of 12- or 15-HETE on the levels of zonula occludens protein 1 (ZO-1), reactive oxygen species (ROS), NOX2, pVEGF-R2 and pSHP1 was examined in the presence or absence of inhibitors of NADPH oxidase. In vivo studies were performed using Ins2Akita mice treated with or without the 12/15-LOX inhibitor baicalein. Levels of HETE and inflammatory mediators were examined by LC/MS and Multiplex Immunoassay respectively. ROS generation and NOX2 expression were also measured in mice retinas. 12- and 15- HETE significantly increased permeability and reduced TER and ZO-1expression in REC. VEGF-R2 inhibitor reduced the permeability effect of 12-HETE. Treatment of REC with HETE also increased ROS generation and expression of NOX2 and pVEGF-R2 and decreased pSHP1 expression. Treatment of diabetic mice with baicalein significantly decreased retinal HETE, ICAM-1, VCAM-1, IL-6, ROS generation, and NOX2 expression. Baicalein also reduced pVEGF-R2 while restored pSHP1 levels in diabetic retina. Our findings suggest that 12/15-LOX contributes to vascular hyperpermeability during DR via NADPH oxidase dependent mechanism which involves suppression of protein tyrosine phosphatase and activation of VEGF-R2 signal pathway.
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Affiliation(s)
- Amira Othman
- Department of Oral Biology/Anatomy, College of Dental Medicine, Georgia Regents University (GRU), Augusta, Georgia, United States of America
- Department of Anatomy, Mansoura University, Mansoura, Egypt
| | - Saif Ahmad
- Department of Ophthalmology and Vision Discovery Institute, Medical College of Georgia, Georgia Regents University (GRU), Augusta, Georgia, United States of America
| | - Sylvia Megyerdi
- Department of Oral Biology/Anatomy, College of Dental Medicine, Georgia Regents University (GRU), Augusta, Georgia, United States of America
| | - Rene Mussell
- Department of Oral Biology/Anatomy, College of Dental Medicine, Georgia Regents University (GRU), Augusta, Georgia, United States of America
| | - Karishma Choksi
- Department of Oral Biology/Anatomy, College of Dental Medicine, Georgia Regents University (GRU), Augusta, Georgia, United States of America
| | - Krishna Rao Maddipati
- Department of Pathology, Wayne States University, Detroit, Michigan, United States of America
| | - Ahmed Elmarakby
- Department of Oral Biology/Anatomy, College of Dental Medicine, Georgia Regents University (GRU), Augusta, Georgia, United States of America
- Vascular Biology Center, Medical College of Georgia, Georgia Regents University (GRU), Augusta, Georgia, United States of America
| | - Nasser Rizk
- Department of Health Sciences, College of Science, Qatar University, Doha, Qatar
| | - Mohamed Al-Shabrawey
- Department of Oral Biology/Anatomy, College of Dental Medicine, Georgia Regents University (GRU), Augusta, Georgia, United States of America
- Department of Anatomy, Mansoura University, Mansoura, Egypt
- Department of Ophthalmology and Vision Discovery Institute, Medical College of Georgia, Georgia Regents University (GRU), Augusta, Georgia, United States of America
- Vascular Biology Center, Medical College of Georgia, Georgia Regents University (GRU), Augusta, Georgia, United States of America
- * E-mail:
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Gregus AM, Dumlao DS, Wei SC, Norris PC, Catella LC, Meyerstein FG, Buczynski MW, Steinauer JJ, Fitzsimmons BL, Yaksh TL, Dennis EA. Systematic analysis of rat 12/15-lipoxygenase enzymes reveals critical role for spinal eLOX3 hepoxilin synthase activity in inflammatory hyperalgesia. FASEB J 2013; 27:1939-49. [PMID: 23382512 DOI: 10.1096/fj.12-217414] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Previously, we observed significant increases in spinal 12-lipoxygenase (LOX) metabolites, in particular, hepoxilins, which contribute to peripheral inflammation-induced tactile allodynia. However, the enzymatic sources of hepoxilin synthase (HXS) activity in rats remain elusive. Therefore, we overexpressed each of the 6 rat 12/15-LOX enzymes in HEK-293T cells and measured by LC-MS/MS the formation of HXB3, 12-HETE, 8-HETE, and 15-HETE from arachidonic acid (AA) at baseline and in the presence of LOX inhibitors (NDGA, AA-861, CDC, baicalein, and PD146176) vs. vehicle-treated and mock-transfected controls. We detected the following primary intrinsic activities: 12-LOX (Alox12, Alox15), 15-LOX (Alox15b), and HXS (Alox12, Alox15). Similar to human and mouse orthologs, proteins encoded by rat Alox12b and Alox12e possessed minimal 12-LOX activity with AA as substrate, while eLOX3 (encoded by Aloxe3) exhibited HXS without 12-LOX activity when coexpressed with Alox12b or supplemented with 12-HpETE. CDC potently inhibited HXS and 12-LOX activity in vitro (relative IC50s: CDC, ~0.5 and 0.8 μM, respectively) and carrageenan-evoked tactile allodynia in vivo. Notably, peripheral inflammation significantly increased spinal eLOX3; intrathecal pretreatment with either siRNA targeting Aloxe3 or an eLOX3-selective antibody attenuated the associated allodynia. These findings implicate spinal eLOX3-mediated hepoxilin synthesis in inflammatory hyperesthesia and underscore the importance of developing more selective 12-LOX/HXS inhibitors.
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Affiliation(s)
- Ann M Gregus
- Department of Anesthesiology, University of California-San Diego, La Jolla, CA 92093, USA
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Haeggström JZ, Funk CD. Lipoxygenase and leukotriene pathways: biochemistry, biology, and roles in disease. Chem Rev 2011; 111:5866-98. [PMID: 21936577 DOI: 10.1021/cr200246d] [Citation(s) in RCA: 591] [Impact Index Per Article: 45.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Jesper Z Haeggström
- Department of Medical Biochemistry and Biophysics, Division of Chemistry 2, Karolinska Institutet, S-171 77 Stockholm, Sweden.
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Cho KJ, Seo JM, Kim JH. Bioactive lipoxygenase metabolites stimulation of NADPH oxidases and reactive oxygen species. Mol Cells 2011; 32:1-5. [PMID: 21424583 PMCID: PMC3887656 DOI: 10.1007/s10059-011-1021-7] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Accepted: 02/22/2011] [Indexed: 12/16/2022] Open
Abstract
In mammalian cells, reactive oxygen species (ROS) are produced via a variety of cellular oxidative processes, including the activity of NADPH oxidases (NOX), the activity of xanthine oxidases, the metabolism of arachidonic acid (AA) by lipoxygenases (LOX) and cyclooxygenases (COX), and the mitochondrial respiratory chain. Although NOX-generated ROS are the best characterized examples of ROS in mammalian cells, ROS are also generated by the oxidative metabolism (e.g., via LOX and COX) of AA that is released from the membrane phospholipids via the activity of cytosolic phospholipase A(2) (cPLA(2)). Recently, growing evidence suggests that LOX- and COX-generated AA metabolites can induce ROS generation by stimulating NOX and that a potential signaling connection exits between the LOX/COX metabolites and NOX. In this review, we discuss the results of recent studies that report the generation of ROS by LOX metabolites, especially 5-LOX metabolites, via NOX stimulation. In particular, we have focused on the contribution of leukotriene B(4) (LTB(4)), a potent bioactive eicosanoid that is derived from 5-LOX, and its receptors, BLT1 and BLT2, to NOX stimulation through a signaling mechanism that leads to ROS generation.
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Affiliation(s)
| | - Ji-Min Seo
- These authors contributed equally to this work
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Al-Shabrawey M, Mussell R, Kahook K, Tawfik A, Eladl M, Sarthy V, Nussbaum J, El-Marakby A, Park SY, Gurel Z, Sheibani N, Maddipati KR. Increased expression and activity of 12-lipoxygenase in oxygen-induced ischemic retinopathy and proliferative diabetic retinopathy: implications in retinal neovascularization. Diabetes 2011; 60:614-24. [PMID: 21228311 PMCID: PMC3028363 DOI: 10.2337/db10-0008] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE Arachidonic acid is metabolized by 12-lipoxygenase (12-LOX) to 12-hydroxyeicosatetraenoic acid (12-HETE) and has an important role in the regulation of angiogenesis and endothelial cell proliferation and migration. The goal of this study was to investigate whether 12-LOX plays a role in retinal neovascularization (NV). RESEARCH DESIGN AND METHODS Experiments were performed using retinas from a murine model of oxygen-induced ischemic retinopathy (OIR) that was treated with and without the LOX pathway inhibitor, baicalein, or lacking 12-LOX. We also analyzed vitreous samples from patients with and without proliferative diabetic retinopathy (PDR). Western blotting and RT-PCR were used to assess the expression of 12-LOX, vascular endothelial growth factor (VEGF), and pigment epithelium-derived factor (PEDF). Liquid chromatography-mass spectrometry was used to assess the amounts of HETEs in the murine retina and human vitreous samples. The effects of 12-HETE on VEGF and PEDF expression were evaluated in Müller cells (rMCs), primary mouse retinal pigment epithelial cells, and astrocytes. RESULTS Retinal NV during OIR was associated with increased 12-LOX expression and 12-, 15-, and 5-HETE production. The amounts of HETEs also were significantly higher in the vitreous of diabetic patients with PDR. Retinal NV was markedly abrogated in mice treated with baicalein or mice lacking 12-LOX. This was associated with decreased VEGF expression and restoration of PEDF levels. PEDF expression was reduced in 12-HETE-treated rMCs, astrocytes, and the retinal pigment epithelium. Only rMCs and astrocytes showed increased VEGF expression by 12-HETE. CONCLUSIONS 12-LOX and its product HETE are important regulators of retinal NV through modulation of VEGF and PEDF expression and could provide a new therapeutic target to prevent and treat ischemic retinopathy.
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Affiliation(s)
- Mohamed Al-Shabrawey
- Department of Oral Biology and Anatomy, Medical College of Georgia, Augusta, Georgia, USA.
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23
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Buczynski MW, Dumlao DS, Dennis EA. Thematic Review Series: Proteomics. An integrated omics analysis of eicosanoid biology. J Lipid Res 2009; 50:1015-38. [PMID: 19244215 PMCID: PMC2681385 DOI: 10.1194/jlr.r900004-jlr200] [Citation(s) in RCA: 397] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Revised: 02/23/2009] [Indexed: 11/20/2022] Open
Abstract
Eicosanoids have been implicated in a vast number of devastating inflammatory conditions, including arthritis, atherosclerosis, pain, and cancer. Currently, over a hundred different eicosanoids have been identified, with many having potent bioactive signaling capacity. These lipid metabolites are synthesized de novo by at least 50 unique enzymes, many of which have been cloned and characterized. Due to the extensive characterization of eicosanoid biosynthetic pathways, this field provides a unique framework for integrating genomics, proteomics, and metabolomics toward the investigation of disease pathology. To facilitate a concerted systems biology approach, this review outlines the proteins implicated in eicosanoid biosynthesis and signaling in human, mouse, and rat. Applications of the extensive genomic and lipidomic research to date illustrate the questions in eicosanoid signaling that could be uniquely addressed by a thorough analysis of the entire eicosanoid proteome.
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Affiliation(s)
| | | | - Edward A. Dennis
- Department of Chemistry and Biochemistry, Department of Pharmacology, and School of Medicine, University of California, San Diego, La Jolla, CA 92093
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24
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Navar LG, Arendshorst WJ, Pallone TL, Inscho EW, Imig JD, Bell PD. The Renal Microcirculation. Compr Physiol 2008. [DOI: 10.1002/cphy.cp020413] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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25
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Prasad VVTS, Nithipatikom K, Harder DR. Ceramide elevates 12-hydroxyeicosatetraenoic acid levels and upregulates 12-lipoxygenase in rat primary hippocampal cell cultures containing predominantly astrocytes. Neurochem Int 2008; 53:220-9. [PMID: 18680775 DOI: 10.1016/j.neuint.2008.07.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2008] [Revised: 06/01/2008] [Accepted: 07/01/2008] [Indexed: 10/21/2022]
Abstract
We report, exogenous addition of ceramide significantly increases 12-hydroxyeicosatetraenoic acid [12-(S)-HETE] levels, in a dose-dependent manner. 12-(S)-HETE levels, in 20, 30 and 40microM ceramide exposed rat primary hippocampal cell cultures containing predominantly astrocytes and few neurons and other glial cells (the cultured hippocampal cells were predominantly astrocytes amounting to over 99% of total cells with few neurons and other glial cells) amounted to 207, 260 and 408% of the controls, respectively. However, dihydroceramide, an inactive analog of ceramide did not alter the levels of 12-(S)-HETE. Ceramide also increased the mRNA and protein expression, and activity of 12-lipoxygease (12-LOX) needed for the synthesis of 12(S)-HETE. These results indicate a possible link between ceramide and 12-LOX pathway. However, ceramide did not alter expression of 5-lipoxygenase (5-LOX), another member of the lipoxygenase family. However, ceramide upregulated expression of cytosolic phospholipase-A(2) (cPLA(2)) and cyclooxygenase-2 (COX-2). Further, ceramide caused a significant increase in the levels of reactive oxygen species (ROS). Ceramide-mediated generation of ROS was inhibited by baicalien but not by indomethacin. In addition, ceramide treated cells exhibited increased mRNA expression of DNA damage induced transcript3 (Ddit3). This report which demonstrate induction of pro-carcinogenic 12-LOX pathway by an anticancer ceramide, may be relevant to cancer biologists studying drug resistant tumors and devising potent anticancer therapeutic strategies to treat drug resistant tumors. These results indicate possibility of 12-LOX involvement in ceramide-mediated generation of ROS and cellular oxidative stress. Induction of 12-LOX pathway by ceramide may have implications in understanding pathophysiology of neurodegenerative diseases involving ROS generation and inflammation.
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26
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Navar LG, Arendshorst WJ, Pallone TL, Inscho EW, Imig JD, Bell PD. The Renal Microcirculation. Microcirculation 2008. [DOI: 10.1016/b978-0-12-374530-9.00015-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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27
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Deschamps JD, Gautschi JT, Whitman S, Johnson TA, Gassner NC, Crews P, Holman TR. Discovery of platelet-type 12-human lipoxygenase selective inhibitors by high-throughput screening of structurally diverse libraries. Bioorg Med Chem 2007; 15:6900-8. [PMID: 17826100 PMCID: PMC2203963 DOI: 10.1016/j.bmc.2007.08.015] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2007] [Revised: 08/08/2007] [Accepted: 08/09/2007] [Indexed: 11/30/2022]
Abstract
Human lipoxygenases (hLO) have been implicated in a variety of diseases and cancers and each hLO isozyme appears to have distinct roles in cellular biology. This fact emphasizes the need for discovering selective hLO inhibitors for both understanding the role of specific lipoxygenases in the cell and developing pharmaceutical therapeutics. To this end, we have modified a known lipoxygenase assay for high-throughput (HTP) screening of both the National Cancer Institute (NCI) and the UC Santa Cruz marine extract library (UCSC-MEL) in search of platelet-type 12-hLO (12-hLO) selective inhibitors. The HTP screen led to the characterization of five novel 12-hLO inhibitors from the NCI repository. One is the potent but non-selective michellamine B, a natural product, anti-viral agent. The other four compounds were selective inhibitors against 12-hLO, with three being synthetic compounds and one being alpha-mangostin, a natural product, caspase-3 pathway inhibitor. In addition, a selective inhibitor was isolated from the UCSC-MEL (neodysidenin), which has a unique chemical scaffold for a hLO inhibitor. Due to the unique structure of neodysidenin, steady-state inhibition kinetics were performed and its mode of inhibition against 12-hLO was determined to be competitive (K(i)=17microM) and selective over reticulocyte 15-hLO-1 (K(i) 15-hLO-1/12-hLO>30).
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Affiliation(s)
| | | | | | | | | | | | - Theodore R. Holman
- To whom correspondence should be addressed. TRH, Tel: 831-459-5884, Fax: 831-459-2935,
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28
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Abstract
Arachidonic acid metabolites are vital for the proper control of renal haemodynamics and, when not properly controlled, can contribute to renal vascular injury and end-stage renal disease. Three major enzymatic pathways, COX (cyclo-oxygenase), CYP450 (cytochrome P450) and LOX (lipoxygenase), are responsible for the metabolism of arachidonic acid metabolites to bioactive eicosanoids. These eicosanoids can dilate or constrict the renal vasculature and maintain vascular resistance in the face of changing vasoactive hormones. Renal vascular generation of eicosanoids is altered in pathophysiological conditions such as hypertension, diabetes, metabolic syndrome and acute renal failure. Experimental evidence supports the concept that altered eicosanoid metabolism contributes to renal haemodynamic alterations and the development and progression of nephropathy. The possible beneficial renal vascular actions of enzymatic inhibitors, eicosanoid analogues and receptor antagonists have been examined in hypertension, diabetes and metabolic syndrome. This review highlights the roles of renal vascular eicosanoids in the pathogenesis of nephropathy and therapeutic targets for renal disease related to hypertension, diabetes, metabolic syndrome and acute renal failure.
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Affiliation(s)
- John D Imig
- Vascular Biology Center, Department of Physiology, Medical College of Georgia, Augusta, GA 30912, USA.
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29
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Ivakine EA, Gulban OM, Mortin-Toth SM, Wankiewicz E, Scott C, Spurrell D, Canty A, Danska JS. Molecular Genetic Analysis of the Idd4 Locus Implicates the IFN Response in Type 1 Diabetes Susceptibility in Nonobese Diabetic Mice. THE JOURNAL OF IMMUNOLOGY 2006; 176:2976-90. [PMID: 16493056 DOI: 10.4049/jimmunol.176.5.2976] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
High-resolution mapping and identification of the genes responsible for type 1 diabetes (T1D) has proved difficult because of the multigenic etiology and low penetrance of the disease phenotype in linkage studies. Mouse congenic strains have been useful in refining Idd susceptibility loci in the NOD mouse model and providing a framework for identification of genes underlying complex autoimmune syndromes. Previously, we used NOD and a nonobese diabetes-resistant strain to map the susceptibility to T1D to the Idd4 locus on chromosome 11. Here, we report high-resolution mapping of this locus to 1.4 megabases. The NOD Idd4 locus was fully sequenced, permitting a detailed comparison with C57BL/6 and DBA/2J strains, the progenitors of T1D resistance alleles found in the nonobese diabetes-resistant strain. Gene expression arrays and quantitative real-time PCR were used to prioritize Idd4 candidate genes by comparing macrophages/dendritic cells from congenic strains where allelic variation was confined to the Idd4 interval. The differentially expressed genes either were mapped to Idd4 or were components of the IFN response pathway regulated in trans by Idd4. Reflecting central roles of Idd4 genes in Ag presentation, arachidonic acid metabolism and inflammation, phagocytosis, and lymphocyte trafficking, our combined analyses identified Alox15, Alox12e, Psmb6, Pld2, and Cxcl16 as excellent candidate genes for the effects of the Idd4 locus.
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Affiliation(s)
- Evgueni A Ivakine
- Program in Developmental Biology, Hospital for Sick Children, Toronto, Ontario, Canada
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30
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Abstract
The eye must contain highly evolved programs to limit inflammation and promote wound healing as an errant response can lead to blindness. However, pathways that protect the delicate visual axis and account for its atypical inflammatory responses remain to be clearly defined. Hence, research efforts have been initiated to elucidate the role of the anti-inflammatory LXA4 circuits in the eye. LXA4 is formed in healthy and injured corneas and both its receptor and 12/15-lipoxygenase are predominantly expressed in epithelial cells. An essential role for LXA4 in preserving ocular function is supported by 12/15-LOX deficient mice that exhibit a phenotype of impaired wound healing and LXA4 formation. A novel epithelial bioaction role for LXA4 has been uncovered in the cornea as topical LXA4 promotes wound healing and limits the sequelae of injury. These emerging studies indicate that the LXA4 circuit may hold a fundamental role in maintaining an ocular environment that actively restricts inflammation while promoting wound healing.
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Affiliation(s)
- Karsten Gronert
- Department of Pharmacology, New York Medical College, Basic Science Building, Valhalla, NY 10595, USA.
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31
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González-Núñez D, Solé M, Natarajan R, Poch E. 12-Lipoxygenase metabolism in mouse distal convoluted tubule cells. Kidney Int 2005; 67:178-86. [PMID: 15610241 DOI: 10.1111/j.1523-1755.2005.00068.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Several lines of evidence point to the 12-lipoxygenase (12-LOX) family as important mediators in hypertension, diabetes, and other cardiovascular diseases. The kidney has been a main focus for research of the role of this pathway in several disease models. While most of the studies have focused on mesangial or vascular cells, less is known about 12-LOX regulation at the renal tubular level. The aim of the study was to characterize the expression and regulation by hormones of the family of 12-LOX in mouse distal convoluted tubule at the molecular level. METHODS An immortalized mouse distal convoluted tubule (mDCT) cell line was used. mRNA and protein levels were assessed by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot, respectively, while 12(S)-HETE production was evaluated by enzyme-linked immunosorbent assay (ELISA). Cells were challenged with aldosterone, angiotensin II, 8Br-cAMP, and vasopressin. RESULTS We showed that both platelet (P) and leukocyte (L)-type 12-LOX are expressed in the mDCT cell line, as well as in distal tubules of human kidneys. The production of 12(S)-HETE by mDCT cells was increased in response to cAMP (by two-fold) and by vasopressin (by 1.5-fold). In contrast, neither aldosterone nor angiotensin II exerted appreciable effects on 12(S)-HETE production. The mRNA and protein levels of P-12LOX and L-12LOX were not changed by the different hormones, suggesting that they may act by modulating enzyme activity. We further have demonstrated that this mDCT cell line also expressed the recently cloned 12(R)-LOX. CONCLUSION mDCT cells show an active 12-LOX metabolism that appears to be modulated by cAMP and vasopressin.
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Affiliation(s)
- Daniel González-Núñez
- Servicio de Nefrologia, Laboratorio de Hormonal, Departamento de Anatomia Patologica, Hospital Clinic, Barcelona, Spain
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32
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Di-Poï N, Ng CY, Tan NS, Yang Z, Hemmings BA, Desvergne B, Michalik L, Wahli W. Epithelium-mesenchyme interactions control the activity of peroxisome proliferator-activated receptor beta/delta during hair follicle development. Mol Cell Biol 2005; 25:1696-712. [PMID: 15713628 PMCID: PMC549363 DOI: 10.1128/mcb.25.5.1696-1712.2005] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Hair follicle morphogenesis depends on a delicate balance between cell proliferation and apoptosis, which involves epithelium-mesenchyme interactions. We show that peroxisome proliferator-activated receptor beta/delta (PPARbeta/delta) and Akt1 are highly expressed in follicular keratinocytes throughout hair follicle development. Interestingly, PPARbeta/delta- and Akt1-deficient mice exhibit similar retardation of postnatal hair follicle morphogenesis, particularly at the hair peg stage, revealing a new important function for both factors in the growth of early hair follicles. We demonstrate that a time-regulated activation of the PPARbeta/delta protein in follicular keratinocytes involves the up-regulation of the cyclooxygenase 2 enzyme by a mesenchymal paracrine factor, the hepatocyte growth factor. Subsequent PPARbeta/delta-mediated temporal activation of the antiapoptotic Akt1 pathway in vivo protects keratinocytes from hair pegs against apoptosis, which is required for normal hair follicle development. Together, these results demonstrate that epithelium-mesenchyme interactions in the skin regulate the activity of PPARbeta/delta during hair follicle development via the control of ligand production and provide important new insights into the molecular biology of hair growth.
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Affiliation(s)
- Nicolas Di-Poï
- Center for Integrative Genomics, Biology Building, University of Lausanne, CH-1015 Lausanne, Switzerland
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A role for the mouse 12/15-lipoxygenase pathway in promoting epithelial wound healing and host defense. J Biol Chem 2005; 280:15267-78. [PMID: 15708862 DOI: 10.1074/jbc.m410638200] [Citation(s) in RCA: 233] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The surface of the eye actively suppresses inflammation while maintaining a remarkable capacity for epithelial wound repair. Our understanding of mechanisms that balance inflammatory/reparative responses to provide effective host defense while preserving tissue function is limited, in particular, in the cornea. Lipoxin A(4) (LXA(4)) and docosahexaenoic acid-derived neuroprotectin D1 (NPD1) are lipid autacoids formed by 12/15-lipoxygenase (LOX) pathways that exhibit anti-inflammatory and neuroprotective properties. Here, we demonstrate that mouse corneas generate endogenous LXA(4) and NPD1. 12/15-LOX (Alox15) and LXA(4) receptor mRNA expression as well as LXA(4) formation were abrogated by epithelial removal and restored during wound healing. Amplification of these pathways by topical treatment with LXA(4) or NPD1 (1 microg) increased the rate of re-epithelialization (65-90%, n = 6-10, p < 0.03) and attenuated the sequelae of thermal injury. In contrast, the proinflammatory eicosanoids, LTB(4) and 12R-hydroxyeicosatrienoic acid, had no impact on corneal re-epithelialization. Epithelial removal induced a temporally defined influx of neutrophils into the stroma as well as formation of the proinflammatory chemokine KC. Topical treatment with LXA(4) and NPD1 significantly increased PMNs in the cornea while abrogating KC formation by 60%. More importantly, Alox15-deficient mice exhibited a defect in both corneal re-epithelialization and neutrophil recruitment that correlated with a 43% reduction in endogenous LXA(4) formation. Collectively, these results identify a novel action for the mouse 12/15-LOX (Alox15) and its products, LXA(4) and NPD1, in wound healing that is distinct from their well established anti-inflammatory properties.
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Wang H, Li J, Follett PL, Zhang Y, Cotanche DA, Jensen FE, Volpe JJ, Rosenberg PA. 12-Lipoxygenase plays a key role in cell death caused by glutathione depletion and arachidonic acid in rat oligodendrocytes. Eur J Neurosci 2004; 20:2049-58. [PMID: 15450084 DOI: 10.1111/j.1460-9568.2004.03650.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Oxidative injury to premyelinating oligodendrocytes (preOLs) in developing white matter has been implicated in the pathogenesis of periventricular leukomalacia, the lesion underlying most cases of cerebral palsy in premature infants. In this study, we investigated the pathways of OL death induced by intracellular glutathione (GSH) depletion. We found that the lipoxygenase (LOX) inhibitors AA-861 and BMD-122 (N-benzyl-N-hydroxy-5-phenylpentamide; BHPP), but not the cyclooxygenase (COX) inhibitor indomethacin, fully protected the cells from GSH depletion caused by cystine deprivation. Arachidonic acid (AA), the substrate for 12-LOX, potentiated the toxicity of mild cystine deprivation and at higher concentration was itself toxic. This toxicity was also blocked by 12-LOX inhibitors. Consistent with a role for 12-LOX in the cell death pathway, 12-LOX activity increased following cystine deprivation in OLs. Blocking 12-LOX with AA-861 effectively inhibited the accumulation of reactive oxygen species (ROS) induced by cystine deprivation. These data suggest that, in OLs, intracellular GSH depletion leads to activation of 12-LOX, ROS accumulation and cell death. Mature OLs were more resistant than preOLs to cystine deprivation. The difference in sensitivity was not due to a difference in 12-LOX activity but rather appeared to be related to the presence of stronger antioxidant defense mechanisms in mature OLs. These results suggest that 12-LOX activation plays a key role in oxidative stress-induced OL death.
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Affiliation(s)
- Hong Wang
- Department of Neurology, Children's Hospital and Harvard Medical School, Boston, MA 02115, USA
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Schneider C, Strayhorn WD, Brantley DM, Nanney LB, Yull FE, Brash AR. Upregulation of 8-lipoxygenase in the dermatitis of IkappaB-alpha-deficient mice. J Invest Dermatol 2004; 122:691-8. [PMID: 15086555 DOI: 10.1111/j.0022-202x.2004.22329.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Neonatal mice deficient in IkappaB-alpha, an inhibitor of the ubiquitous transcription factor NF-kappaB, develop severe and widespread dermatitis shortly after birth. In humans, inflammatory skin disorders such as psoriasis are associated with accumulation in the skin of the unusual arachidonic acid metabolite 12R-hydroxyeicosatetraenoic acid (12R-HETE), a product of the enzyme 12R-lipoxygenase. To examine the etiology of the murine IkappaB-alpha-deficient skin phenotype, we investigated the expression of lipoxygenases and the metabolism of exogenous arachidonic acid in the skin. In the IkappaB-alpha-deficient animals, the major lipoxygenase metabolite was 8S-HETE, formed together with a minor amount of 12S-HETE; 12R-HETE synthesis was undetectable. Skin from the wild-type littermates formed 12S-HETE as the almost exclusive lipoxygenase metabolite. Upregulation of 8S-lipoxygenase (8-LOX) in IkappaB-alpha-deficient mice was confirmed at the transcriptional and translational level using ribonuclease protection assay and western analysis. In immunohistochemical studies, increased expression of 8-LOX was detected in the stratum granulosum of the epidermis. In the stratum granulosum, 8-LOX may be involved in the terminal differentiation of keratinocytes. Although mouse 8S-lipoxygenase and human 12R-lipoxygenase are not ortholog genes, we speculate that in mouse and humans the two different enzymes may fulfill equivalent functions in the progression of inflammatory dermatoses.
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Affiliation(s)
- Claus Schneider
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-6602, USA.
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McDonnell M, Li H, Funk CD. Characterization of epidermal 12(S) and 12(R) lipoxygenases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003; 507:147-53. [PMID: 12664578 DOI: 10.1007/978-1-4615-0193-0_23] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Maeve McDonnell
- Center for Experimental Therapeutics, Rm 820 BRB II/III, University of Pennsylvania, Philadelphia, PA 19104, USA
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Abstract
Arachidonate 12-lipoxygenase introduces a molecular oxygen at carbon 12 of arachidonic acid to generate a 12-hydroperoxy derivative. The enzymes generate 12-hydroperoxy derivatives with either S- or R-configurations. There are three isoforms of 12S-lipoxygenases named after the cells where they were first identified; platelet, leukocyte and epidermis. The leukocyte-type enzyme is widely distributed among cells, but the tissue distribution varies substantially from species to species. The platelet and epidermal enzymes are present in only a relatively limited number of cell types. Although the structures and enzymatic properties of the three isoforms of 12S-lipoxygenases have been elucidated, the physiological roles of the 12S-lipoxygenases are not yet fully understood. There are important roles for the enzymes and their products in several biological systems including those involved in atherosclerosis and neurotransmission.
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Affiliation(s)
- Tanihiro Yoshimoto
- Department of Molecular Pharmacology, Kanazawa University Graduate School of Medicine, Japan.
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Shimada H, Ichikawa H, Ohki M. Potential involvement of the AML1-MTG8 fusion protein in the granulocytic maturation characteristic of the t(8;21) acute myelogenous leukemia revealed by microarray analysis. Leukemia 2002; 16:874-85. [PMID: 11986950 DOI: 10.1038/sj.leu.2402465] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2001] [Accepted: 01/15/2002] [Indexed: 11/08/2022]
Abstract
The AML1 (RUNX1)-MTG8 (ETO) fusion transcription factor generated by the t(8;21) translocation is believed to deregulate the expression of genes that are crucial for normal differentiation and proliferation of hematopoietic progenitors, resulting in acute myelogenous leukemia. To elucidate the role of AML1-MTG8 in leukemogenesis, we used oligonucleotide microarrays to detect alterations in gene expression caused by ectopic expression of AML1-MTG8 in a murine myeloid progenitor cell line, L-G. Microarray analysis of approximately 6500 genes identified 32 candidate genes under the downstream control of AML1-MTG8. Among the 32 genes, 23 were not known to be regulated by AML1-MTG8. These included many granule protein genes and several cell surface antigen genes. Interestingly, AML1-MTG8 enhanced the expression of several genes that are usually induced during granulocytic differentiation, particularly those encoding azurophil granule proteins, including cathepsin G, myeloperoxidase and lysozyme. This indicates that AML1-MTG8 induces partial differentiation of myeloid progenitor cells into promyelocytes in the absence of the usual differentiation signals, while it inhibits terminal differentiation into mature granulocytes. Thus, AML1-MTG8 itself may play a crucial role in defining a unique cytologic type with abnormal maturation, characteristic of t(8;21) acute myelogenous leukemia.
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MESH Headings
- Acute-Phase Proteins/drug effects
- Acute-Phase Proteins/genetics
- Animals
- Case-Control Studies
- Cathepsin G
- Cathepsins/drug effects
- Cathepsins/genetics
- Cell Differentiation/drug effects
- Cell Differentiation/genetics
- Cell Line
- Chromosomes, Human, Pair 21
- Chromosomes, Human, Pair 8
- Core Binding Factor Alpha 2 Subunit
- Gene Expression Profiling
- Gene Expression Regulation/drug effects
- Gene Expression Regulation/genetics
- Granulocytes/drug effects
- Granulocytes/pathology
- Humans
- Leukemia, Myeloid, Acute/etiology
- Leukemia, Myeloid, Acute/pathology
- Lipocalin-2
- Lipocalins
- Mice
- Muramidase/drug effects
- Muramidase/genetics
- Myeloid Progenitor Cells/cytology
- Myeloid Progenitor Cells/drug effects
- Oligonucleotide Array Sequence Analysis
- Oncogene Proteins/drug effects
- Oncogene Proteins/genetics
- Oncogene Proteins, Fusion/genetics
- Oncogene Proteins, Fusion/pharmacology
- Oncogene Proteins, Fusion/physiology
- Peroxidase/drug effects
- Peroxidase/genetics
- Proto-Oncogene Proteins
- RUNX1 Translocation Partner 1 Protein
- Serine Endopeptidases
- Transcription Factors/genetics
- Transcription Factors/pharmacology
- Transcription Factors/physiology
- Transduction, Genetic
- Translocation, Genetic
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Affiliation(s)
- H Shimada
- Cancer Genomics Division, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
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Kawajiri H, Hsi LC, Kamitani H, Ikawa H, Geller M, Ward T, Eling TE, Glasgow WC. Arachidonic and linoleic acid metabolism in mouse intestinal tissue: evidence for novel lipoxygenase activity. Arch Biochem Biophys 2002; 398:51-60. [PMID: 11811948 DOI: 10.1006/abbi.2001.2685] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous studies in our laboratory revealed a high expression of 15-lipoxygenase-1 in human colorectal carcinomas, suggesting the importance of lipoxygenase in colorectal tumor development. In this report, we have investigated the metabolism of arachidonic and linoleic acid by intestinal tissues of Min mice, an animal model for intestinal neoplasia. The polyp and normal tissues from Min mice intestine were homogenized, incubated with arachidonic or linoleic acid, and analyzed by reverse-, straight-, and chiral-phase HPLC. Arachidonic acid was converted to prostaglandins E2 and F2alpha. Little 12- or 15-hydroxyeicosatetraenoic acid was detected. Cyclooxygenase (COX)-2 was detected in polyps and the adjacent normal tissues by Western immunoblotting, but neither COX-1 nor leukocyte-type 12-lipoxygenase, the murine ortholog to human 15-lipoxygenase-1, was detected. These tissue homogenates converted linoleic acid to an equal mixture of 9(S)- and 13(S)-hydroxyoctadecadienoic acid (HODE). Inhibition of lipoxygenase activity with nordihydroguaiaretic acid blocked HODEs formation, but the COX inhibitor indomethacin did not. Degenerative-nested PCR analyses using primers encoded by highly conserved sequences in lipoxygenases detected 5-lipoxygenase, leukocyte-type 12-lipoxygenase, platelet-type 12-lipoxygenase, 8-lipoxygenase, and epidermis-type lipoxygenase-3 in mouse intestinal tissue. All of these PCR products represent known lipoxygenase that are not reported to utilize linoleic acid preferentially as substrate and do not metabolize linoleic acid to an equal mixture of 9(S)- and 13(S)-HODE. This somewhat unique profile of linoleate product formation in Min mice intestinal tissue suggests the presence of an uncharacterized and potentially novel lipoxygenase(s) that may play a role in intestinal epithelial cell differentiation and tumor development.
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Affiliation(s)
- Hiroo Kawajiri
- Eicosanoid Biochemistry Section, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA
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40
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Muller K, Altmann R, Prinz H. 2-Arylalkyl-substituted anthracenones as inhibitors of 12-lipoxygenase enzymes. 2. Structure-activity relationships of the linker chain. Eur J Med Chem 2002; 37:83-9. [PMID: 11841878 DOI: 10.1016/s0223-5234(01)01291-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A series of 2-arylalkyl-substituted anthracenones were tested as inhibitors of three types of 12-lipoxygenase isoforms in epidermal homogenate of mice, bovine platelets and porcine leukocytes. Their inhibitory activities were compared with those to inhibit the 5-lipoxygenase enzyme in bovine leukocytes. The compounds were synthesised by Marschalk, Wittig or Horner-Emmons reaction at the anthracenedione stage and then reduced to the anthracenones. Structure-activity relationship for the chain linking the anthracenone nucleus and the phenyl ring terminus was investigated. The 2-phenylethyl analogues were among the most potent inhibitors, and 3,4-dimethoxy-substituted 10f was identified as a selective inhibitor of the 12-LO enzymes over 5-LO. Selectivity for 12-LO isoforms was observed with an increase in the overall lipophilicity of the inhibitors. However, none of the linker chains of the 2-substituted anthracenones provided inhibitors that were able to discriminate between the 12-LO isoforms.
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Affiliation(s)
- Klaus Muller
- Westfalische Wilhelms-Universitat Munster, Institut fur Pharmazeutische und Medizinische Chemie, Hittorfstrasse 58-62, D-48149 Munster, Germany.
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Antón R, Camacho M, Puig L, Vila L. Hepoxilin B3 and its enzymatically formed derivative trioxilin B3 are incorporated into phospholipids in psoriatic lesions. J Invest Dermatol 2002; 118:139-46. [PMID: 11851887 DOI: 10.1046/j.0022-202x.2001.01593.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In previous studies we observed that normal human epidermis forms 12-oxo-eicosatetraenoic acid (12-oxo-ETE) and hepoxilin B3 (HxB3) as major eicosanoids, both being elevated in psoriasis. We also observed that normal epidermis, in a reaction probably catalyzed by 12-lipoxygenase, only synthesize one of the two possible 10-hydroxy epimers of HxB3. We have now extended these previous studies investigating further transformation of HxB3 into trioxilin B3 (TrXB3) and esterification of both into phospholipids. Phospholipids were extracted from normal epidermis and from psoriatic scales. A combination of high performance liquid chromatography and gas chromatography-mass spectrometry analysis demonstrated the occurrence of HxB3 and TrXB3 in the phospholipids of psoriatic lesions. Alkaline- and phospholipase-A2-mediated hydrolysis of the phospholipids yielded similar quantities of both HxB3 and TrXB3 indicating their preference for the sn-2 position of glycerophospholipids. The thin layer chromatography analysis of the phospholipid classes after incubation of epidermal cells with [14C]-labeled HxB3, TrXB3, 12-hydroxy-eicosatetraenoic acid (12-HETE), 12-oxo-ETE, or 15-HETE showed that 12-HETE was the most esterified (12-HETE >15-HETE > TrXB3 > 12-oxo-ETE > HxB3). HxB3 and TrXB3 were mainly esterified in phosphatidyl-choline and phosphatidyl-ethanolamine. HxB3 was also enzymatically converted into TrXB3 in vitro. HxB3 epoxide hydrolase-like activity was not observed when boiled tissue was incubated with [14C]-HxB3, this activity being located in the cytosol fraction (100,000 x g supernatant) of fresh tissue. These findings suggest that in vivo some part of HxB3 is transformed into TrXB3 and both compounds are partially incorporated into the phospholipids.
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Affiliation(s)
- Rosa Antón
- Laboratory of Inflammation Mediators, Institute of Research of the Santa Creu i Sant Pau Hospital, Barcelona, Spain
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Schneider C, Keeney DS, Boeglin WE, Brash AR. Detection and cellular localization of 12R-lipoxygenase in human tonsils. Arch Biochem Biophys 2001; 386:268-74. [PMID: 11368351 DOI: 10.1006/abbi.2000.2217] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Formation of the 12R-lipoxygenase product, 12R-hydroperoxyeicosatetraenoic acid (12R-HPETE), has been detected previously only in human skin (Boeglin et al. (1998) Proc. Natl. Acad. Sci. USA 95, 6744). The unexpected appearance of an EST sequence (AA649213) for human 12R-lipoxygenase from germinal center B lymphocytes purified from human tonsils prompted our search for the existence of the enzyme in this novel source. Incubation of [1-14C]arachidonic acid with homogenates of human tonsillar tissue yielded mixtures of radiolabeled 12-HETE and 15-HETE. Stereochemical analysis showed varying ratios of 12S- and 12R-HETE, while 15-HETE was exclusively of the S-configuration. Using stereospecifically labeled [10S-3H]- and [10R-3H]arachidonic acid substrates we detected pro-R hydrogen abstraction at carbon 10 associated with formation of 12R-HETE. This mechanistic evidence implicates a 12R-lipoxygenase in the biosynthesis of 12R-HETE. The mRNA for the enzyme was identified in tonsils by RT-PCR and Northern analysis. The cellular distribution was established by in situ hybridization. Unexpectedly, hybridization was not observed in the lymphocytes of the germinal centers. Specific reaction was restricted to squamous epithelial cells, including the epithelium lining the tonsillar crypts. In this location the 12R-lipoxygenase might help regulate differentiation of the epithelium or participate in lymphocyte- epithelial cell interactions.
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Affiliation(s)
- C Schneider
- Department of Pharmacology, Vanderbilt University Medical School, Nashville, Tennessee 37232, USA
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Gabel SA, London RE, Funk CD, Steenbergen C, Murphy E. Leukocyte-type 12-lipoxygenase-deficient mice show impaired ischemic preconditioning-induced cardioprotection. Am J Physiol Heart Circ Physiol 2001; 280:H1963-9. [PMID: 11299195 DOI: 10.1152/ajpheart.2001.280.5.h1963] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To investigate the role of 12-lipoxygenase in preconditioning, we examined whether hearts lacking the "leukocyte-type" 12-lipoxygenase (12-LOKO) would be protected by preconditioning. In hearts from wild-type (WT) and 12-LOKO mice, left ventricular developed pressure (LVDP) and (31)P NMR were monitored during treatment (+/-preconditioning) and during global ischemia and reperfusion. Postischemic function (rate-pressure product, percentage of initial value) measured after 20 min of ischemia and 40 min of reperfusion was significantly improved by preconditioning in WT hearts (78 +/- 12% in preconditioned vs. 44 +/- 7% in nonpreconditioned hearts) but not in 12-LOKO hearts (47 +/- 7% in preconditioned vs. 33 +/- 10% in nonpreconditioned hearts). Postischemic recovery of phosphocreatine was significantly better in WT preconditioned hearts than in 12-LOKO preconditioned hearts. Preconditioning significantly reduced the fall in intracellular pH during sustained ischemia in both WT and 12-LOKO hearts, suggesting that attenuation of the fall in pH during ischemia can be dissociated from preconditioning-induced protection. Necrosis was assessed after 25 min of ischemia and 2 h of reperfusion using 2,3,5-triphenyltetrazolium chloride. In WT hearts, preconditioning significantly reduced the area of necrosis (26 +/- 4%) compared with nonpreconditioned hearts (62 +/- 10%) but not in 12-LOKO hearts (85 +/- 3% in preconditioned vs. 63 +/- 11% in nonpreconditioned hearts). Preconditioning resulted in a significant increase in 12(S)-hydroxyeicosatetraenoic acid in WT but not in 12-LOKO hearts. These data demonstrate that 12-lipoxygenase is important in preconditioning.
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Affiliation(s)
- S A Gabel
- National Institute of Environmental Health Sciences, Research Triangle Park 27709, Durham, North Carolina 27710, USA
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De Petrocellis L, Bisogno T, Maccarrone M, Davis JB, Finazzi-Agro A, Di Marzo V. The activity of anandamide at vanilloid VR1 receptors requires facilitated transport across the cell membrane and is limited by intracellular metabolism. J Biol Chem 2001; 276:12856-63. [PMID: 11278420 DOI: 10.1074/jbc.m008555200] [Citation(s) in RCA: 267] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The endogenous ligand of CB(1) cannabinoid receptors, anandamide, is also a full agonist at vanilloid VR1 receptors for capsaicin and resiniferatoxin, thereby causing an increase in cytosolic Ca(2+) concentration in human VR1-overexpressing (hVR1-HEK) cells. Two selective inhibitors of anandamide facilitated transport into cells, VDM11 and VDM13, and two inhibitors of anandamide enzymatic hydrolysis, phenylmethylsulfonyl fluoride and methylarachidonoyl fluorophosphonate, inhibited and enhanced, respectively, the VR1-mediated effect of anandamide, but not of resiniferatoxin or capsaicin. The nitric oxide donor, sodium nitroprusside, known to stimulate anandamide transport, enhanced anandamide effect on the cytosolic Ca(2+) concentration. Accordingly, hVR1-HEK cells contain an anandamide membrane transporter inhibited by VDM11 and VDM13 and activated by sodium nitroprusside, and an anandamide hydrolase activity sensitive to phenylmethylsulfonyl fluoride and methylarachidonoyl fluorophosphonate, and a fatty acid amide hydrolase transcript. These findings suggest the following. (i) Anandamide activates VR1 receptors by acting at an intracellular site. (ii) Degradation by fatty acid amide hydrolase limits anandamide activity on VR1; and (iii) the anandamide membrane transporter inhibitors can be used to distinguish between CB(1) or VR1 receptor-mediated actions of anandamide. By contrast, the CB(1) receptor antagonist SR141716A inhibited also the VR1-mediated effect of anandamide and capsaicin on cytosolic Ca(2+) concentration, although at concentrations higher than those required for CB(1) antagonism.
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Affiliation(s)
- L De Petrocellis
- Endocannabinoid Research Group, Istituto per la Chimica di Molecole di Interesse Biologico and the Istituto di Cibernetica, C. N. R., Via Toiano 6, 80072, Arco Felice, Napoli, Italy
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Siebert M, Krieg P, Lehmann WD, Marks F, Fürstenberger G. Enzymic characterization of epidermis-derived 12-lipoxygenase isoenzymes. Biochem J 2001; 355:97-104. [PMID: 11256953 PMCID: PMC1221716 DOI: 10.1042/0264-6021:3550097] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Substrate selectivity and other enzymic characteristics of two epidermis-derived lipoxygenases (LOXs), the epidermis-type (e) (12S)-LOX and (12R)-LOX, were compared with those of the platelet-type (p) (12S)-LOX. In contrast with p(12S)-LOX, e(12S)-LOX and (12R)-LOX exhibited no or very low reactivity towards the customary substrates linoleic acid and arachidonic acid but metabolized the corresponding fatty acid methyl esters, which, in contrast, were not accepted as substrates by p(12S)-LOX. Other esters of arachidonic acid and linoleic acid, including propan-2-yl and cholesterol esters, 1-palmitoyl-2-arachidonyl-sn-glycero-3-phosphocholine, 1-palmitoyl-2-linoleyl-sn-glycero-3-phosphoethanolamine, and ceramide 1 carrying an omega-linoleic acid ester, were not metabolized by these three LOX isoenzymes. Among various polyunsaturated fatty acids the isomeric eicosatrienoic acids were found to be oxygenated by e(12S)-LOX but not by (12R)-LOX. 4,7,10,13,16,19-Docosahexaenoic acid as a substrate was restricted to p(12S)-LOX. Variations in the pH and the Ca(2+) content of the incubation medium affected the catalytic potential only slightly. Whereas (12R)-LOX activity increased in the presence of Ca(2+) and with an acidic pH, Ca(2+) had no effect on p(12S)-LOX and e(12S)-LOX; an acidic pH decreased the catalytic activity of the latter two. However, the catalytic activity of the epidermis-type isoenzymes, but not of p(12S)-LOX, was found to be markedly increased in the presence of DMSO. Under these conditions, e(12S)-LOX and (12R)-LOX oxygenated 4,7,10,13,16,19-docosahexaenoic acid to 14-hydroxy-4,7,10,12,16,19-docosahexaenoic acid and 13-hydroxy-4,7,10,14,16,19-docosahexaenoic acid respectively. In addition, (9R)-hydroxyoctadeca-10,12-dienoic acid methyl ester was generated from linoleic acid methyl ester by (12R)-LOX. Independently of the substrate, the catalytic activity of e(12S)-LOX and (12R)-LOX was always at most 2% of that of p(12S)-LOX with arachidonic acid as substrate.
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Affiliation(s)
- M Siebert
- Research Program on Tumor Cell Regulation (B0500), Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
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Abstract
Tumor cell proliferation and metastasis proceed via a network of interdependent molecular events with a vast array of molecular players and signal transduction mechanisms differing in various types of human tumors. In the sequence of events necessary for carcinogenesis, arachidonate metabolites have been documented to play a significant role at several steps. Arachidonate metabolism in human cells occurs via several enzymatic pathways, including enzymes such as cyclo-oxygenases and lipoxygenases. This review pays particular attention to one member of the lipoxygenase family of enzymes, namely 12-lipoxygenase, since an arachidonate metabolite generated via 12-lipoxygenase action, 12(S)-HETE, has been shown to elicit various prometastatic effects of tumor cells in vivo and in vitro. We focus especially on mechanisms of activation and modulation of 12-lipoxygenase expression in human tumor cells, since various tumor cells express 12-lipoxygenase or are responsive to metabolites derived from 12-lipoxygenase action, thus offering a potential for successful therapeutic intervention against such tumors.
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Affiliation(s)
- Wolfgang Hagmann
- Deutsches Krebsforschungszentrum, Division of Tumor Biochemistry, Heidelberg, Germany
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Jisaka M, Boeglin WE, Kim RB, Brash AR. Site-Directed Mutagenesis Studies on a Putative Fifth Iron Ligand of Mouse 8S-Lipoxygenase: Retention of Catalytic Activity on Mutation of Serine-558 to Asparagine, Histidine, or Alanine. Arch Biochem Biophys 2001; 386:136-42. [PMID: 11368335 DOI: 10.1006/abbi.2000.2175] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The reported crystal structures of plant and animal lipoxygenases (LOX) show that the nonheme iron in the catalytic domain is ligated by three histidines, the C-terminal isoleucine, and in certain structures also by a fifth iron ligand, an asparagine or histidine residue. Mouse 8-LOX and its homologues (e.g., human 15-LOX-2) are unique in having a serine in place of the usual Asn or His in this fifth position. To investigate the importance of the residue in mouse 8-LOX structure-function, the serine-558 was replaced by asparagine, histidine, or alanine using oligonucleotide-directed mutagenesis. Wild-type mouse 8-LOX and the mutant cDNAs were expressed in HeLa cells infected with vaccinia virus encoding T7 RNA polymerase and their relative lipoxygenase activities assessed by incubation with [14C]arachidonic acid or [14C]linoleic acid followed by HPLC analysis of the products. The Ser558Asn and Ser558His mutants had equivalent or greater activity than wild-type 8-LOX. They also exhibited some 15-LOX activity, indicating that small structural perturbations (in this case to a residue identical in mouse 8-LOX and its 15-LOX-2 homologues) can interchange the positional specificity of these closely related enzymes. Remarkably, the Ser558Ala mutant exhibited significant 8-LOX activity, indicating that this position is not an essential iron ligand in the enzyme. We conclude that mouse 8-LOX is catalytically competent with only four amino acid iron ligands, and that Ser-558 of the wild-type enzyme does not play an essential role in catalysis.
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Affiliation(s)
- M Jisaka
- Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-6602, USA.
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Chen XS, Funk CD. The N-terminal "beta-barrel" domain of 5-lipoxygenase is essential for nuclear membrane translocation. J Biol Chem 2001; 276:811-8. [PMID: 11042185 DOI: 10.1074/jbc.m008203200] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
5-Lipoxygenase is the key enzyme in the formation of leukotrienes, which are potent lipid mediators of asthma pathophysiology. This enzyme translocates to the nuclear envelope in a calcium-dependent manner for leukotriene biosynthesis. Eight green fluorescent protein (GFP)-lipoxygenase constructs, representing the major human and mouse enzymes within this family, were constructed and their cDNAs transfected into human embryonic kidney 293 cells. Of these eight lipoxygenases, only the 5-lipoxygenase was clearly nuclear localized and translocated to the nuclear envelope upon stimulation with the calcium ionophore. The N-terminal "beta -barrel" domain of 5-lipoxygenase, but not the catalytic domain, was necessary and sufficient for nuclear envelope translocation. The GFP-N-terminal 5-lipoxygenase domain translocated faster than GFP-5-lipoxygenase. beta-Barrel/catalytic domain chimeras with 12- and 15-lipoxygenase indicated that only the N-terminal domain of 5-lipoxygenase could carry out this translocation function. Mutations of iron atom binding ligands (His550 or deletion of C-terminal isoleucine) that disrupt nuclear localization do not alter translocation capacity indicating distinct determinants of nuclear localization and translocation. Moreover, data show that GFP-5-lipoxygenase beta-barrel containing constructs can translocate to the nuclear membrane whether cytoplasmic or nuclear localized. Thus, the predicted beta-barrel domain of 5-lipoxygenase may function like the C2 domain within protein kinase C and cytosolic phospholipase A(2) with unique determinants that direct its localization to the nuclear envelope.
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Affiliation(s)
- X S Chen
- Department of Pharmacology, Center for Experimental Therapeutics University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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Metzler DE, Metzler CM, Sauke DJ. Specific Aspects of Lipid Metabolism. Biochemistry 2001. [DOI: 10.1016/b978-012492543-4/50024-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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50
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McDonnell M, Davis W, Li H, Funk CD. Characterization of the murine epidermal 12/15-lipoxygenase. Prostaglandins Other Lipid Mediat 2001; 63:93-107. [PMID: 11204741 DOI: 10.1016/s0090-6980(00)00100-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The murine lipoxygenase (LO) family consists of at least seven members classified according to the HETE (hydroxyeicosatetraenoic acid) metabolite generated during arachidonic acid metabolism and the site of tissue expression. At present there are four 12-lipoxygenases that are functionally distinct, vary in cell and tissue distribution, catalytic activity and each are products of separate, linked genes. They are "platelet-type" 12-LO (P-12LO), "leukocyte-type" 12-LO (L-12LO), "epidermal-type" 12-LO (e-12LO) and the most recently discovered 12(R)-LO. In this report we characterize e-12LO, which was overexpressed in the baculovirus/insect cell expression system. The enzyme functions as a dual specificity 12/15-lipoxygenase with a 12-HETE/15-HETE product ratio of approximately 6:1 with arachidonic acid as substrate. Several other polyunsaturated fatty acids served as substrates for e-12LO such as gamma-linolenic, dihomo-gamma-linolenic and eicosapentaenoic acids. A green fluorescent protein/e-12LO fusion protein was localized to the cytosol of transfected HEK 293 cells. The e-12LO gene was expressed in mouse oocytes and early embryos. Western blot analysis revealed high level expression in postnatal day 3 mouse epidermal lysates. Together these data suggest that e-12LO plays a role in normal epidermal function and as yet an undiscovered role in early development.
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Affiliation(s)
- M McDonnell
- Department of Pharmacology and Center for Experimental Therapeutics, University of Pennsylvania, Philadelphia 19104 USA
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