1
|
Palmer MA, Benatzy Y, Brüne B. Murine Alox8 versus the human ALOX15B ortholog: differences and similarities. Pflugers Arch 2024:10.1007/s00424-024-02961-w. [PMID: 38637408 DOI: 10.1007/s00424-024-02961-w] [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: 02/16/2024] [Revised: 03/30/2024] [Accepted: 04/03/2024] [Indexed: 04/20/2024]
Abstract
Human arachidonate 15-lipoxygenase type B is a lipoxygenase that catalyzes the peroxidation of arachidonic acid at carbon-15. The corresponding murine ortholog however has 8-lipoxygenase activity. Both enzymes oxygenate polyunsaturated fatty acids in S-chirality with singular reaction specificity, although they generate a different product pattern. Furthermore, while both enzymes utilize both esterified fatty acids and fatty acid hydro(pero)xides as substrates, they differ with respect to the orientation of the fatty acid in their substrate-binding pocket. While ALOX15B accepts the fatty acid "tail-first," Alox8 oxygenates the free fatty acid with its "head-first." These differences in substrate orientation and thus in regio- and stereospecificity are thought to be determined by distinct amino acid residues. Towards their biological function, both enzymes share a commonality in regulating cholesterol homeostasis in macrophages, and Alox8 knockdown is associated with reduced atherosclerosis in mice. Additional roles have been linked to lung inflammation along with tumor suppressor activity. This review focuses on the current knowledge of the enzymatic activity of human ALOX15B and murine Alox8, along with their association with diseases.
Collapse
Affiliation(s)
- Megan A Palmer
- Institute of Biochemistry I, Faculty of Medicine, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany.
| | - Yvonne Benatzy
- Institute of Biochemistry I, Faculty of Medicine, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany.
| | - Bernhard Brüne
- Institute of Biochemistry I, Faculty of Medicine, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
- Frankfurt Cancer Institute, Goethe University Frankfurt, Frankfurt, Germany
- Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Frankfurt, Germany
- German Cancer Consortium (DKTK), Partner Site Frankfurt, Frankfurt, Germany
| |
Collapse
|
2
|
Amoah AS, Pestov NB, Korneenko TV, Prokhorenko IA, Kurakin GF, Barlev NA. Lipoxygenases at the Intersection of Infection and Carcinogenesis. Int J Mol Sci 2024; 25:3961. [PMID: 38612771 PMCID: PMC11011848 DOI: 10.3390/ijms25073961] [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: 01/31/2024] [Revised: 03/08/2024] [Accepted: 03/28/2024] [Indexed: 04/14/2024] Open
Abstract
The persisting presence of opportunistic pathogens like Pseudomonas aeruginosa poses a significant threat to many immunocompromised cancer patients with pulmonary infections. This review highlights the complexity of interactions in the host's defensive eicosanoid signaling network and its hijacking by pathogenic bacteria to their own advantage. Human lipoxygenases (ALOXs) and their mouse counterparts are integral elements of the innate immune system, mostly operating in the pro-inflammatory mode. Taking into account the indispensable role of inflammation in carcinogenesis, lipoxygenases have counteracting roles in this process. In addition to describing the structure-function of lipoxygenases in this review, we discuss their roles in such critical processes as cancer cell signaling, metastases, death of cancer and immune cells through ferroptosis, as well as the roles of ALOXs in carcinogenesis promoted by pathogenic infections. Finally, we discuss perspectives of novel oncotherapeutic approaches to harness lipoxygenase signaling in tumors.
Collapse
Affiliation(s)
- Abdul-Saleem Amoah
- Institute of Biomedical Chemistry, Moscow 119121, Russia; (A.-S.A.); (N.A.B.)
- Laboratory of Molecular Oncology, Phystech School of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny 141701, Russia
| | - Nikolay B. Pestov
- Institute of Biomedical Chemistry, Moscow 119121, Russia; (A.-S.A.); (N.A.B.)
- Group of Cross-Linking Enzymes, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow 117997, Russia; (T.V.K.); (I.A.P.)
- Laboratory of Tick-Borne Encephalitis and Other Viral Encephalitides, Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products, Moscow 108819, Russia
- Vavilov Institute of General Genetics, Moscow 119991, Russia
| | - Tatyana V. Korneenko
- Group of Cross-Linking Enzymes, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow 117997, Russia; (T.V.K.); (I.A.P.)
| | - Igor A. Prokhorenko
- Group of Cross-Linking Enzymes, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow 117997, Russia; (T.V.K.); (I.A.P.)
| | - Georgy F. Kurakin
- Department of Biochemistry, Pirogov Russian National Research Medical University, Moscow 117513, Russia;
| | - Nickolai A. Barlev
- Institute of Biomedical Chemistry, Moscow 119121, Russia; (A.-S.A.); (N.A.B.)
- Laboratory of Tick-Borne Encephalitis and Other Viral Encephalitides, Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products, Moscow 108819, Russia
| |
Collapse
|
3
|
Reisch F, Heydeck D, Schäfer M, Rothe M, Yang J, Stehling S, Püschel GP, Kuhn H. Knock-in mice expressing a humanized arachidonic acid 15-lipoxygenase (Alox15) carry a partly dysfunctional erythropoietic system. Cell Mol Biol Lett 2023; 28:97. [PMID: 38030974 PMCID: PMC10685687 DOI: 10.1186/s11658-023-00511-3] [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: 05/17/2023] [Accepted: 11/07/2023] [Indexed: 12/01/2023] Open
Abstract
Arachidonic acid 15-lipoxygenases (ALOX15) play a role in mammalian erythropoiesis but they have also been implicated in inflammatory processes. Seven intact Alox genes have been detected in the mouse reference genome and the mouse Alox15 gene is structurally similar to the orthologous genes of other mammals. However, mouse and human ALOX15 orthologs have different functional characteristics. Human ALOX15 converts C20 polyenoic fatty acids like arachidonic acid mainly to the n-6 hydroperoxide. In contrast, the n-9 hydroperoxide is the major oxygenation product formed by mouse Alox15. Previous experiments indicated that Leu353Phe exchange in recombinant mouse Alox15 humanized the catalytic properties of the enzyme. To investigate whether this functional humanization might also work in vivo and to characterize the functional consequences of mouse Alox15 humanization we generated Alox15 knock-in mice (Alox15-KI), in which the Alox15 gene was modified in such a way that the animals express the arachidonic acid 15-lipoxygenating Leu353Phe mutant instead of the arachidonic acid 12-lipoxygenating wildtype enzyme. These mice develop normally, they are fully fertile but display modified plasma oxylipidomes. In young individuals, the basic hematological parameters were not different when Alox15-KI mice and outbred wildtype controls were compared. However, when growing older male Alox15-KI mice develop signs of dysfunctional erythropoiesis such as reduced hematocrit, lower erythrocyte counts and attenuated hemoglobin concentration. These differences were paralleled by an improved ex vivo osmotic resistance of the peripheral red blood cells. Interestingly, such differences were not observed in female individuals suggesting gender specific effects. In summary, these data indicated that functional humanization of mouse Alox15 induces defective erythropoiesis in aged male individuals.
Collapse
Affiliation(s)
- Florian Reisch
- Department of Biochemistry, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt Universität Zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
- Institute for Nutritional Sciences, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558, Nuthetal, Germany
- Lipidomix GmbH, Robert-Rössle-Straße 10, 13125, Berlin, Germany
| | - Dagmar Heydeck
- Department of Biochemistry, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt Universität Zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Marjann Schäfer
- Department of Biochemistry, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt Universität Zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
- Institute for Nutritional Sciences, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558, Nuthetal, Germany
| | - Michael Rothe
- Lipidomix GmbH, Robert-Rössle-Straße 10, 13125, Berlin, Germany
| | - Jiaxing Yang
- Department of Biochemistry, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt Universität Zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Sabine Stehling
- Department of Biochemistry, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt Universität Zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Gerhard P Püschel
- Institute for Nutritional Sciences, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558, Nuthetal, Germany
| | - Hartmut Kuhn
- Department of Biochemistry, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt Universität Zu Berlin, Charitéplatz 1, 10117, Berlin, Germany.
| |
Collapse
|
4
|
Brenna JT, Sergeeva MG, Pestov NB, Korneenko TV, Shchepinov MS. Arachidonic acid: reconciling the dichotomy of its oxidative cascade through specific deuteration. Free Radic Res 2023:1-11. [PMID: 37897398 DOI: 10.1080/10715762.2023.2277145] [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: 05/16/2023] [Accepted: 10/18/2023] [Indexed: 10/30/2023]
Abstract
A new approach to attenuating pathological inflammatory reactions by buffering the eicosanoid pathways with oxidation-resistant hexadeuterated arachidonic acid (D-ARA) is discussed. Enzymatic processing of ARA, released by phospholipase A2, by lipoxygenases, cyclooxygenases, and cytochromes yields a wide range of bioactive eicosanoids, including pro-inflammation, pro-angiogenesis and pro-thrombosis species that, when produced in excess, are an underlying cause of pathology. Conversely, some products of ARA oxidation possess pro-resolving properties. Non-enzymatic free radical oxidation of ARA generates another large group of products such as isoprostanes and their metabolites, associated with inflammation, ischemia-reperfusion stress, and atherosclerosis. A separate group comprises reactive carbonyl derivatives that irreversibly damage diverse biomolecules. Being resistant to both enzymatic and non-enzymatic oxidation pathways due to large kinetic isotope effects, D-ARA may play a role in mitigating inflammation-related disorders and conditions, including inflammaging.
Collapse
Affiliation(s)
- J Thomas Brenna
- University of TX at Austin, Departments of Pediatrics, of Chemistry, and of Nutrition, Dell Pediatric Research Institute, Austin, TX, USA
| | - Marina G Sergeeva
- Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Nikolay B Pestov
- Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products, Laboratory of Tick-Borne Encephalitis and other Encephalitides, Moscow, Russia
- Institute of Biomedical Chemistry, Moscow, Russia
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Group of Cross-Linking Enzymes, Moscow, Russia
| | - Tatyana V Korneenko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Group of Cross-Linking Enzymes, Moscow, Russia
| | | |
Collapse
|
5
|
Schäfer M, Reisch F, Labuz D, Machelska H, Stehling S, Püschel GP, Rothe M, Heydeck D, Kuhn H. Humanization of the Reaction Specificity of Mouse Alox15b Inversely Modified the Susceptibility of Corresponding Knock-In Mice in Two Different Animal Inflammation Models. Int J Mol Sci 2023; 24:11034. [PMID: 37446212 PMCID: PMC10341735 DOI: 10.3390/ijms241311034] [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: 05/05/2023] [Revised: 06/28/2023] [Accepted: 06/29/2023] [Indexed: 07/15/2023] Open
Abstract
Mammalian arachidonic acid lipoxygenases (ALOXs) have been implicated in the pathogenesis of inflammatory diseases, and its pro- and anti-inflammatory effects have been reported for different ALOX-isoforms. Human ALOX15B oxygenates arachidonic acid to its 15-hydroperoxy derivative, whereas the corresponding 8-hydroperoxide is formed by mouse Alox15b (Alox8). This functional difference impacts the biosynthetic capacity of the two enzymes for creating pro- and anti-inflammatory eicosanoids. To explore the functional consequences of the humanization of the reaction specificity of mouse Alox15b in vivo, we tested Alox15b knock-in mice that express the arachidonic acid 15-lipoxygenating Tyr603Asp and His604Val double mutant of Alox15b, instead of the arachidonic acid 8-lipoxygenating wildtype enzyme, in two different animal inflammation models. In the dextran sodium sulfate-induced colitis model, female Alox15b-KI mice lost significantly more bodyweight during the acute phase of inflammation and recovered less rapidly during the resolution phase. Although we observed significant differences in the colonic levels of selected pro- and anti-inflammatory eicosanoids during the time-course of inflammation, there were no differences between the two genotypes at any time-point of the disease. In Freund's complete adjuvant-induced paw edema model, Alox15b-KI mice were less susceptible than outbred wildtype controls, though we did not observe significant differences in pain perception (Hargreaves-test, von Frey-test) when the two genotypes were compared. our data indicate that humanization of the reaction specificity of mouse Alox15b (Alox8) sensitizes mice for dextran sodium sulfate-induced experimental colitis, but partly protects the animals in the complete Freund's adjuvant-induced paw edema model.
Collapse
Affiliation(s)
- Marjann Schäfer
- Department of Biochemistry, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, D-10117 Berlin, Germany; (M.S.); (F.R.); (S.S.); (D.H.)
- Institute for Nutritional Sciences, University Potsdam, Arthur-Scheunert-Allee 114–116, D-14558 Nuthetal, Germany;
| | - Florian Reisch
- Department of Biochemistry, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, D-10117 Berlin, Germany; (M.S.); (F.R.); (S.S.); (D.H.)
- Institute for Nutritional Sciences, University Potsdam, Arthur-Scheunert-Allee 114–116, D-14558 Nuthetal, Germany;
| | - Dominika Labuz
- Department of Experimental Anesthesiology, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Hindenburgdamm 30, D-12203 Berlin, Germany; (D.L.); (H.M.)
| | - Halina Machelska
- Department of Experimental Anesthesiology, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Hindenburgdamm 30, D-12203 Berlin, Germany; (D.L.); (H.M.)
| | - Sabine Stehling
- Department of Biochemistry, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, D-10117 Berlin, Germany; (M.S.); (F.R.); (S.S.); (D.H.)
| | - Gerhard P. Püschel
- Institute for Nutritional Sciences, University Potsdam, Arthur-Scheunert-Allee 114–116, D-14558 Nuthetal, Germany;
| | - Michael Rothe
- Lipidomix GmbH, Robert-Roessle-Straße 10, D-13125 Berlin, Germany;
| | - Dagmar Heydeck
- Department of Biochemistry, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, D-10117 Berlin, Germany; (M.S.); (F.R.); (S.S.); (D.H.)
| | - Hartmut Kuhn
- Department of Biochemistry, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, D-10117 Berlin, Germany; (M.S.); (F.R.); (S.S.); (D.H.)
| |
Collapse
|
6
|
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.
Collapse
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
| |
Collapse
|
7
|
Functional Characterization of Transgenic Mice Overexpressing Human 15-Lipoxygenase-1 (ALOX15) under the Control of the aP2 Promoter. Int J Mol Sci 2023; 24:ijms24054815. [PMID: 36902243 PMCID: PMC10003068 DOI: 10.3390/ijms24054815] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/24/2023] [Accepted: 02/27/2023] [Indexed: 03/06/2023] Open
Abstract
Arachidonic acid lipoxygenases (ALOX) have been implicated in the pathogenesis of inflammatory, hyperproliferative, neurodegenerative, and metabolic diseases, but the physiological function of ALOX15 still remains a matter of discussion. To contribute to this discussion, we created transgenic mice (aP2-ALOX15 mice) expressing human ALOX15 under the control of the aP2 (adipocyte fatty acid binding protein 2) promoter, which directs expression of the transgene to mesenchymal cells. Fluorescence in situ hybridization and whole-genome sequencing indicated transgene insertion into the E1-2 region of chromosome 2. The transgene was highly expressed in adipocytes, bone marrow cells, and peritoneal macrophages, and ex vivo activity assays proved the catalytic activity of the transgenic enzyme. LC-MS/MS-based plasma oxylipidome analyses of the aP2-ALOX15 mice suggested in vivo activity of the transgenic enzyme. The aP2-ALOX15 mice were viable, could reproduce normally, and did not show major phenotypic alterations when compared with wildtype control animals. However, they exhibited gender-specific differences with wildtype controls when their body-weight kinetics were evaluated during adolescence and early adulthood. The aP2-ALOX15 mice characterized here can now be used for gain-of-function studies evaluating the biological role of ALOX15 in adipose tissue and hematopoietic cells.
Collapse
|
8
|
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.
Collapse
|
9
|
Benatzy Y, Palmer MA, Brüne B. Arachidonate 15-lipoxygenase type B: Regulation, function, and its role in pathophysiology. Front Pharmacol 2022; 13:1042420. [PMID: 36438817 PMCID: PMC9682198 DOI: 10.3389/fphar.2022.1042420] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 10/26/2022] [Indexed: 10/30/2023] Open
Abstract
As a lipoxygenase (LOX), arachidonate 15-lipoxygenase type B (ALOX15B) peroxidizes polyenoic fatty acids (PUFAs) including arachidonic acid (AA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and linoleic acid (LA) to their corresponding fatty acid hydroperoxides. Distinctive to ALOX15B, fatty acid oxygenation occurs with positional specificity, catalyzed by the non-heme iron containing active site, and in addition to free PUFAs, membrane-esterified fatty acids serve as substrates for ALOX15B. Like other LOX enzymes, ALOX15B is linked to the formation of specialized pro-resolving lipid mediators (SPMs), and altered expression is apparent in various inflammatory diseases such as asthma, psoriasis, and atherosclerosis. In primary human macrophages, ALOX15B expression is associated with cellular cholesterol homeostasis and is induced by hypoxia. Like in inflammation, the role of ALOX15B in cancer is inconclusive. In prostate and breast carcinomas, ALOX15B is attributed a tumor-suppressive role, whereas in colorectal cancer, ALOX15B expression is associated with a poorer prognosis. As the biological function of ALOX15B remains an open question, this review aims to provide a comprehensive overview of the current state of research related to ALOX15B.
Collapse
Affiliation(s)
- Yvonne Benatzy
- Faculty of Medicine, Institute of Biochemistry I, Goethe University Frankfurt, Frankfurt, Germany
| | - Megan A. Palmer
- Faculty of Medicine, Institute of Biochemistry I, Goethe University Frankfurt, Frankfurt, Germany
| | - Bernhard Brüne
- Faculty of Medicine, Institute of Biochemistry I, Goethe University Frankfurt, Frankfurt, Germany
- Frankfurt Cancer Institute, Goethe University Frankfurt, Frankfurt, Germany
- German Cancer Consortium (DKTK), Partner Site Frankfurt, Frankfurt, Germany
- Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Frankfurt, Germany
| |
Collapse
|