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Huff HC, Kim JS, Ojha A, Sinha S, Das A. Real time changes in the expression of eicosanoid synthesizing enzymes during inflammation. Prostaglandins Other Lipid Mediat 2024; 174:106839. [PMID: 38679226 DOI: 10.1016/j.prostaglandins.2024.106839] [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: 12/03/2023] [Revised: 04/22/2024] [Accepted: 04/25/2024] [Indexed: 05/01/2024]
Abstract
Immune responses during inflammation involve complex, well-coordinated lipid signaling pathways. Eicosanoids are a class of lipid signaling molecules derived from polyunsaturated fatty acids such as arachidonic acid and constitute a major network that controls inflammation and its subsequent resolution. Arachidonic acid is metabolized by enzymes in three different pathways to form a variety of lipid metabolites that can be either pro- or anti-inflammatory. Therefore, an understanding of the time-dependent gene expression, lipid metabolite profiles and cytokine profiles during the initial inflammatory response is necessary, as it will allow for the design of time-dependent therapeutics. Herein, we investigate the multi-level regulation of this process. After stimulating RAW 264.7 cells, a mouse-derived macrophage cell line commonly used to examine inflammatory responses, we examine the gene expression of 44 relevant lipid metabolizing enzymes from the different eicosanoid synthesizing classes. We also measure the formation of lipid metabolites and production of cytokines at selected time points. Results reveal a dynamic relationship between the time-course of inflammation dependent gene expression of the three eicosanoid synthesizing enzymes.
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Affiliation(s)
- Hannah C Huff
- School of Chemistry and Biochemistry, College of Sciences. Georgia Institute of Technology, IBB, Parker H. Petit Institute for Bioengineering and Biosciences, Atlanta, GA 30332, USA
| | - Justin S Kim
- School of Chemistry and Biochemistry, College of Sciences. Georgia Institute of Technology, IBB, Parker H. Petit Institute for Bioengineering and Biosciences, Atlanta, GA 30332, USA
| | - Abhishek Ojha
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Saurabh Sinha
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Aditi Das
- School of Chemistry and Biochemistry, College of Sciences. Georgia Institute of Technology, IBB, Parker H. Petit Institute for Bioengineering and Biosciences, Atlanta, GA 30332, USA.
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2
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Noguchi S, Tallman KA, Porter NA, Stec DF, Calcutt MW, Boeglin WE, Brash AR. Evaluation of ω-alkynyl-labeled linoleic and arachidonic acids as substrates for recombinant lipoxygenase pathway enzymes. Biochim Biophys Acta Mol Cell Biol Lipids 2023; 1868:159360. [PMID: 37336389 PMCID: PMC10528070 DOI: 10.1016/j.bbalip.2023.159360] [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: 03/24/2023] [Revised: 06/02/2023] [Accepted: 06/11/2023] [Indexed: 06/21/2023]
Abstract
ω-Alkynyl-fatty acids can be used as probes for covalent binding to intracellular macromolecules. To inform future in vivo studies, we determined the rates of reaction of ω-alkynyl-labeled linoleate with recombinant enzymes of the skin 12R-lipoxygenase (12R-LOX) pathway involved in epidermal barrier formation (12R-LOX, epidermal lipoxygenase-3 (eLOX3), and SDR9C7). We also examined the reactivity of ω-alkynyl-arachidonic acid with representative lipoxygenase enzymes employing either "carboxyl end-first" substrate binding (5S-LOX) or "tail-first" (platelet-type 12S-LOX). ω-Alkynyl-linoleic acid was oxygenated by 12R-LOX at 62 ± 9 % of the rate compared to linoleic acid, the alkynyl-9R-HPODE product was isomerized by eLOX3 at only 43 ± 1 % of the natural substrate, whereas its epoxy alcohol product was converted to epoxy ketone linoleic by an NADH-dependent dehydrogenase (SDR9C7) with 91 ± 1 % efficiency. The results suggest the optimal approach will be application of the 12R-LOX/eLOX3-derived epoxyalcohol, which should be most efficiently incorporated into the pathway and allow subsequent analysis of covalent binding to epidermal proteins. Regarding the orientation of substrate binding in LOX catalysis, our results and previous reports suggest the ω-alkynyl group has a stronger inhibitory effect on tail-first binding, as might be expected. Beyond slowing the reaction, however, we found that the tail-first binding and transformation of ω-alkynyl-arachidonic acid by platelet-type 12S-LOX results in almost complete enzyme inactivation, possibly due to reactive intermediates blocking the enzyme active site. Overall, the results reinforce the conclusion that ω-alkynyl-fatty acids are suitable for selected applications after appropriate reactivity is established.
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Affiliation(s)
- Saori Noguchi
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, United States of America
| | - Keri A Tallman
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, United States of America
| | - Ned A Porter
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, United States of America
| | - Donald F Stec
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, United States of America
| | - M Wade Calcutt
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, United States of America
| | - William E Boeglin
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, United States of America
| | - Alan R Brash
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, United States of America.
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Shi C, Li Y, Wan E, Zhang E, Sun L. Construction of an lncRNA model for prognostic prediction of bladder cancer. BMC Med Genomics 2022; 15:257. [PMID: 36514150 DOI: 10.1186/s12920-022-01414-6] [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: 07/19/2022] [Accepted: 12/09/2022] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVE We aimed to investigate the role and potential mechanisms of long non-coding RNAs (lncRNAs) in bladder cancer (BC), as well as determine their prognostic value. METHODS LncRNA expression data and clinical data from BC patients were downloaded from The Cancer Genome Atlas (TCGA) database. R software was used to carry out principal component analysis (PCA), differential analysis, and prognostic analysis. Lasso regression and multivariate Cox regression analyses were performed to identify potential prognostic genes. The expression of five identified genes and their correlation with prognosis were verified using TCGA and GSE13507 datasets. In addition, quantitative real-time polymerase chain reaction (qRT-PCR) was used to confirm the expression of these five genes in cell lines (two human BC cell lines and one human bladder epithelial cell line) and tissues (84 pairs of BC tissues and the corresponding paracancerous tissues). Risk scores that had been generated from the five genes and their prognostic ability were assessed by receiver operating characteristic (ROC) and Kaplan-Meier (KM) curves. Co-expressed genes were screened by WGCNA and analyzed by GO and KEGG, while functional enrichment and immune infiltration analyses were performed using STRING ( https://cn.string-db.org/ ) and TIMER2.0 ( http://timer.cistrome.org/ ) online tools, respectively. RESULTS CYP4F8, FAR2P1, LINC01518, LINC01764, and DTNA were identified as potential prognostic genes. We found that these five genes were differentially expressed in BC tissue, as well as in BC cell lines, and were significantly correlated with the prognosis of BC patients. KM analysis considering risk scores as independent parameters revealed differences in overall survival (OS) by subgroups. The ROC curve revealed that a combined model consisting of all five genes had good predictive ability at 1, 3, and 5 years. GO and KEGG analyses of 567 co-expressed genes revealed that these genes were significantly associated with muscle function. CONCLUSION LncRNAs can be good predictors of BC development and prognosis, and may act as potential tumor markers and therapeutic targets that may be beneficial in helping clinicians decide the most effective treatment strategies.
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Affiliation(s)
- Changlong Shi
- Department of Urology, Huishan District People's Hospital, Wuxi City, Jiangsu, China
| | - Yifei Li
- Department of Urology, Huishan District People's Hospital, Wuxi City, Jiangsu, China
| | - Enming Wan
- Department of Urology, Huishan District People's Hospital, Wuxi City, Jiangsu, China
| | - Enchong Zhang
- Department of Second Urology, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China
| | - Li Sun
- Department of Breast Surgery, Huishan District People's Hospital, Wuxi City, Jiangsu, China.
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D MO, C TZ, R SP. Human orphan cytochromes P450: An update. Curr Drug Metab 2022; 23:CDM-EPUB-128186. [PMID: 36503398 DOI: 10.2174/1389200224666221209153032] [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: 08/05/2022] [Revised: 10/25/2022] [Accepted: 11/11/2022] [Indexed: 12/14/2022]
Abstract
Orphan cytochromes P450 (CYP) are enzymes whose biological functions and substrates are unknown. However, the use of new experimental strategies has allowed obtaining more information about their relevance in the metabolism of endogenous and exogenous compounds. Likewise, the modulation of their expression and activity has been associated with pathogenesis and prognosis in different diseases. In this work, we review the regulatory pathways and the possible role of orphan CYP to provide evidence that allow us to stop considering some of them as orphan enzymes and to propose them as possible therapeutic targets in the design of new strategies for the treatment of diseases associated with CYP-mediated metabolism.
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Affiliation(s)
- Molina-Ortiz D
- Laboratorio de Toxicología Genética, Instituto Nacional de Pediatría, Coyoacán, Mexico City, México, 04530
| | - Torres-Zárate C
- Laboratorio de Toxicología Genética, Instituto Nacional de Pediatría, Coyoacán, Mexico City, México, 04530
| | - Santes-Palacios R
- Laboratorio de Toxicología Genética, Instituto Nacional de Pediatría, Coyoacán, Mexico City, México, 04530
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Simultaneous determination of selected eicosanoids by reversed-phase HPLC method using fluorescence detection and application to rat and human plasma, and rat heart and kidney samples. J Pharm Biomed Anal 2015; 110:12-9. [DOI: 10.1016/j.jpba.2015.02.041] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 02/19/2015] [Accepted: 02/20/2015] [Indexed: 11/22/2022]
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Hannam S, Murray M, Romani L, Tuicakau M, J Whitfeld M. Kava dermopathy in Fiji: an acquired ichthyosis? Int J Dermatol 2014; 53:1490-4. [DOI: 10.1111/ijd.12546] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Sarah Hannam
- Skin and Cancer Foundation Victoria Melbourne Victoria Australia
| | - Michael Murray
- Discipline of Pharmacology School of Medical Sciences, Sydney Medical School, University of Sydney Sydney New South Wales Australia
| | - Lucia Romani
- Kirby Institute University of New South Wales Sydney New South Wales Australia
| | | | - Margot J Whitfeld
- Faculty of Medicine University of NSW Sydney New South Wales Australia
- St. Vincent's Hospital Sydney New South Wales Australia
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Kao D, Chaintreau A, Lepoittevin JP, Giménez-Arnau E. Mechanistic studies on the reactivity of sensitizing allylic hydroperoxides: investigation of the covalent modification of amino acids by carbon-radical intermediates. Toxicol Res (Camb) 2014. [DOI: 10.1039/c3tx50109d] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Alexander SPH, Benson HE, Faccenda E, Pawson AJ, Sharman JL, Spedding M, Peters JA, Harmar AJ. The Concise Guide to PHARMACOLOGY 2013/14: enzymes. Br J Pharmacol 2013; 170:1797-867. [PMID: 24528243 PMCID: PMC3892293 DOI: 10.1111/bph.12451] [Citation(s) in RCA: 415] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The Concise Guide to PHARMACOLOGY 2013/14 provides concise overviews of the key properties of over 2000 human drug targets with their pharmacology, plus links to an open access knowledgebase of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. The full contents can be found at http://onlinelibrary.wiley.com/doi/10.1111/bph.12444/full. Enzymes are one of the seven major pharmacological targets into which the Guide is divided, with the others being G protein-coupled receptors, ligand-gated ion channels, ion channels, nuclear hormone receptors, catalytic receptors and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. A new landscape format has easy to use tables comparing related targets. It is a condensed version of material contemporary to late 2013, which is presented in greater detail and constantly updated on the website www.guidetopharmacology.org, superseding data presented in previous Guides to Receptors and Channels. It is produced in conjunction with NC-IUPHAR and provides the official IUPHAR classification and nomenclature for human drug targets, where appropriate. It consolidates information previously curated and displayed separately in IUPHAR-DB and the Guide to Receptors and Channels, providing a permanent, citable, point-in-time record that will survive database updates.
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Affiliation(s)
- Stephen PH Alexander
- School of Life Sciences, University of Nottingham Medical SchoolNottingham, NG7 2UH, UK
| | - Helen E Benson
- The University/BHF Centre for Cardiovascular Science, University of EdinburghEdinburgh, EH16 4TJ, UK
| | - Elena Faccenda
- The University/BHF Centre for Cardiovascular Science, University of EdinburghEdinburgh, EH16 4TJ, UK
| | - Adam J Pawson
- The University/BHF Centre for Cardiovascular Science, University of EdinburghEdinburgh, EH16 4TJ, UK
| | - Joanna L Sharman
- The University/BHF Centre for Cardiovascular Science, University of EdinburghEdinburgh, EH16 4TJ, UK
| | | | - John A Peters
- Neuroscience Division, Medical Education Institute, Ninewells Hospital and Medical School, University of DundeeDundee, DD1 9SY, UK
| | - Anthony J Harmar
- The University/BHF Centre for Cardiovascular Science, University of EdinburghEdinburgh, EH16 4TJ, UK
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Hardwick JP, Eckman K, Lee YK, Abdelmegeed MA, Esterle A, Chilian WM, Chiang JY, Song BJ. Eicosanoids in metabolic syndrome. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2013; 66:157-266. [PMID: 23433458 DOI: 10.1016/b978-0-12-404717-4.00005-6] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Chronic persistent inflammation plays a significant role in disease pathology of cancer, cardiovascular disease, and metabolic syndrome (MetS). MetS is a constellation of diseases that include obesity, diabetes, hypertension, dyslipidemia, hypertriglyceridemia, and hypercholesterolemia. Nonalcoholic fatty liver disease (NAFLD) is associated with many of the MetS diseases. These metabolic derangements trigger a persistent inflammatory cascade, which includes production of lipid autacoids (eicosanoids) that recruit immune cells to the site of injury and subsequent expression of cytokines and chemokines that amplify the inflammatory response. In acute inflammation, the transcellular synthesis of antiinflammatory eicosanoids resolve inflammation, while persistent activation of the autacoid-cytokine-chemokine cascade in metabolic disease leads to chronic inflammation and accompanying tissue pathology. Many drugs targeting the eicosanoid pathways have been shown to be effective in the treatment of MetS, suggesting a common linkage between inflammation, MetS and drug metabolism. The cross-talk between inflammation and MetS seems apparent because of the growing evidence linking immune cell activation and metabolic disorders such as insulin resistance, dyslipidemia, and hypertriglyceridemia. Thus modulation of lipid metabolism through either dietary adjustment or selective drugs may become a new paradigm in the treatment of metabolic disorders. This review focuses on the mechanisms linking eicosanoid metabolism to persistent inflammation and altered lipid and carbohydrate metabolism in MetS.
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Affiliation(s)
- James P Hardwick
- Biochemistry and Molecular Pathology, Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, Ohio, USA.
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Edson KZ, Rettie AE. CYP4 enzymes as potential drug targets: focus on enzyme multiplicity, inducers and inhibitors, and therapeutic modulation of 20-hydroxyeicosatetraenoic acid (20-HETE) synthase and fatty acid ω-hydroxylase activities. Curr Top Med Chem 2013; 13:1429-40. [PMID: 23688133 PMCID: PMC4245146 DOI: 10.2174/15680266113139990110] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 02/05/2013] [Indexed: 01/06/2023]
Abstract
The Cytochrome P450 4 (CYP4) family of enzymes in humans is comprised of thirteen isozymes that typically catalyze the ω-oxidation of endogenous fatty acids and eicosanoids. Several CYP4 enzymes can biosynthesize 20- hydroxyeicosatetraenoic acid, or 20-HETE, an important signaling eicosanoid involved in regulation of vascular tone and kidney reabsorption. Additionally, accumulation of certain fatty acids is a hallmark of the rare genetic disorders, Refsum disease and X-ALD. Therefore, modulation of CYP4 enzyme activity, either by inhibition or induction, is a potential strategy for drug discovery. Here we review the substrate specificities, sites of expression, genetic regulation, and inhibition by exogenous chemicals of the human CYP4 enzymes, and discuss the targeting of CYP4 enzymes in the development of new treatments for hypertension, stroke, certain cancers and the fatty acid-linked orphan diseases.
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Affiliation(s)
- Katheryne Z. Edson
- Department of Medicinal Chemistry, University of Washington, Box 357610, Seattle, WA 98195
| | - Allan E. Rettie
- Department of Medicinal Chemistry, University of Washington, Box 357610, Seattle, WA 98195, Phone: 206-685-0615, Fax: 206-685-3252
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The expression of epidermal lipoxygenases and transglutaminase-1 is perturbed by NIPAL4 mutations: indications of a common metabolic pathway essential for skin barrier homeostasis. J Invest Dermatol 2012; 132:2368-2375. [PMID: 22622417 DOI: 10.1038/jid.2012.160] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Autosomal recessive congenital ichthyosis (ARCI) is a heterogeneous group of skin barrier diseases due inter alia to mutations in transglutaminase-1 (TGM1), in lipoxygenases (LOXs) of the hepoxilin pathway, and in ichthyin, a putative Mg(2+) transporter encoded by the NIPAL4 gene. In search of a common pathogenic pathway for ARCI, we investigated the epidermal expression of TGM1, 12R-LOX, eLOX-3, and ichthyin in skin biopsies from four healthy controls and nine patients with ARCI. In healthy skin, TGM1, ichthyin, and the LOX enzymes were predominantly expressed in the upper epidermis where colocalization signals could also be demonstrated by in situ proximity ligation assay. In patients with ALOX12B mutations and abnormal 12R-LOX expression, the colocalization signal for eLOX-3 and TGM1 was increased 4-fold. In contrast, patients with NIPAL4 mutations and abnormal ichthyin expression showed increased 12R-LOX and eLOX-3 staining and a colocalization signal of these LOXs that was three times the normal intensity. Treatment of these patients with a retinoid-mimetic drug, liarozole, normalized the expression of 12R-LOX and attenuated the colocalization signal. Altogether, our data indicate that ichthyin and TGM1 are functionally closely related in the lipid processing and that this metabolic pathway can be modified by retinoids.
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CYP4F22 is highly expressed at the site and timing of onset of keratinization during skin development. J Dermatol Sci 2012; 65:156-8. [DOI: 10.1016/j.jdermsci.2011.12.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 12/01/2011] [Accepted: 12/06/2011] [Indexed: 11/27/2022]
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Kelly EJ, Nakano M, Rohatgi P, Yarov-Yarovoy V, Rettie AE. Finding homes for orphan cytochrome P450s: CYP4V2 and CYP4F22 in disease states. Mol Interv 2011; 11:124-32. [PMID: 21540472 DOI: 10.1124/mi.11.2.10] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The cytochrome P450 (CYP) 4 family of enzymes contains several recently identified membersthat are referred to as “orphan P450s” because their endogenous substrates are unknown.Human CYP4V2 and CYP4F22 are two such orphan P450s that are strongly linked to ocular andskin disease, respectively. Genetic analyses have identified a wide spectrum of mutations in the CYP4V2gene from patients suffering from Bietti’s crystalline corneoretinal dystrophy, and mutations in theCYP4F22 gene have been linked to lamellar ichthyosis. The strong gene–disease associations provideunique opportunities for elucidating the substrate specificity of these orphan P450s and unraveling thebiochemical pathways that may be impacted in patients with CYP4V2 and CYP4F22 functional deficits.
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Affiliation(s)
- Edward J Kelly
- Department of Pharmaceutics, University of Washington, Seattle, WA 98195, USA.
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Guengerich FP, Cheng Q. Orphans in the human cytochrome P450 superfamily: approaches to discovering functions and relevance in pharmacology. Pharmacol Rev 2011; 63:684-99. [PMID: 21737533 DOI: 10.1124/pr.110.003525] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
As a result of technical advances in recombinant DNA technology and nucleotide sequencing, entire genome sequences have become available in the past decade and offer potential in understanding diseases. However, a central problem in the biochemical sciences is that the functions of only a fraction of the genes/proteins are known, and this is also an issue in pharmacology. This review is focused on issues related to the functions of cytochrome P450 (P450) enzymes. P450 functions can be categorized in several groups: 1) Some P450s have critical roles in the metabolism of endogenous substrates (e.g., sterols and fat-soluble vitamins). 2) Some P450s are not generally critical to normal physiology but function in relatively nonselective protection from the many xenobiotic chemicals to which mammals (including humans) are exposed in their diets [as well as more anthropomorphic chemicals (e.g., drugs, pesticides)]. 3) Some P450s have not been extensively studied and are termed "orphans" here. With regard to elucidation of any physiological functions of the orphan P450s, the major subject of this review, it is clear that simple trial-and-error approaches with individual substrate candidates will not be very productive in addressing questions about function. A series of liquid chromatography/mass spectrometry/informatics approaches are discussed, along with some successes with both human and bacterial P450s. Current information on what are still considered "orphan" P450s is presented. The potential for application of some of these approaches to other enzyme systems is also discussed.
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Affiliation(s)
- F Peter Guengerich
- Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, 638 Robinson Research Building, 2200 Pierce Avenue, Nashville, Tennessee 37232-0146, USA.
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