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Huang X, Li T, Yang SH, Zhu KD, Wang LS, Dong YL, Huang JQ. Hepatocyte-specific Selenoi deficiency predisposes mice to hepatic steatosis and obesity. FASEB J 2024; 38:e23717. [PMID: 38837270 DOI: 10.1096/fj.202400575rr] [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: 03/13/2024] [Revised: 05/10/2024] [Accepted: 05/21/2024] [Indexed: 06/07/2024]
Abstract
Selenoprotein I (Selenoi) is highly expressed in liver and plays a key role in lipid metabolism as a phosphatidylethanolamine (PE) synthase. However, the precise function of Selenoi in the liver remains elusive. In the study, we generated hepatocyte-specific Selenoi conditional knockout (cKO) mice on a high-fat diet to identify the physiological function of Selenoi. The cKO group exhibited a significant increase in body weight, with a 15.6% and 13.7% increase in fat accumulation in white adipose tissue (WAT) and the liver, respectively. Downregulation of the lipolysis-related protein (p-Hsl) and upregulation of the adipogenesis-related protein (Fasn) were observed in the liver of cKO mice. The cKO group also showed decreased oxygen consumption (VO2), carbon dioxide production (VCO2), and energy expenditure (p < .05). Moreover, various metabolites of the steroid hormone synthesis pathway were affected in the liver of cKO mice. A potential cascade of Selenoi-phosphatidylethanolamine-steroid hormone synthesis might serve as a core mechanism that links hepatocyte-specific Selenoi cKO to biochemical and molecular reactions. In conclusion, we revealed that Selenoi inhibits body fat accumulation and hepatic steatosis and elevates energy consumption; this protein could also be considered a therapeutic target for such related diseases.
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Affiliation(s)
- Xin Huang
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, China
| | - Tong Li
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, China
| | - Shi-Hui Yang
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, China
| | - Kong-di Zhu
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, China
| | - Lian-Shun Wang
- College of Fisheries and Life Science, Dalian Ocean University, Dalian, Liaoning, China
| | - Yu-Lan Dong
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, China
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Jia-Qiang Huang
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, China
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2
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Valentín-Goyco J, Im SC, Auchus RJ. Kinetics of Intermediate Release Enhances P450 11B2-Catalyzed Aldosterone Synthesis. Biochemistry 2024; 63:1026-1037. [PMID: 38564530 DOI: 10.1021/acs.biochem.3c00725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The mitochondrial enzyme cytochrome P450 11B2 (aldosterone synthase) catalyzes the 3 terminal transformations in the biosynthesis of aldosterone from 11-deoxycorticosterone (DOC): 11β-hydroxylation to corticosterone, 18-hydroxylation, and 18-oxidation. Prior studies have shown that P450 11B2 produces more aldosterone from DOC than from the intermediate corticosterone and that the reaction sequence is processive, with intermediates remaining bound to the active site between oxygenation reactions. In contrast, P450 11B1 (11β-hydroxylase), which catalyzes the terminal step in cortisol biosynthesis, shares a 93% amino acid sequence identity with P450 11B2, converts DOC to corticosterone, but cannot synthesize aldosterone from DOC. The biochemical and biophysical properties of P450 11B2, which enable its unique 18-oxygenation activity and processivity, yet are not also represented in P450 11B1, remain unknown. To understand the mechanism of aldosterone biosynthesis, we introduced point mutations at residue 320, which partially exchange the activities of P450 11B1 and P450 11B2 (V320A and A320V, respectively). We then investigated NADPH coupling efficiencies, binding kinetics and affinities, and product formation of purified P450 11B1 and P450 11B2, wild-type, and residue 320 mutations in phospholipid vesicles and nanodiscs. Coupling efficiencies for the 18-hydroxylase reaction with corticosterone as the substrate failed to correlate with aldosterone synthesis, ruling out uncoupling as a relevant mechanism. Conversely, corticosterone dissociation rates correlated inversely with aldosterone production. We conclude that intermediate dissociation kinetics, not coupling efficiency, enable P450 11B2 to synthesize aldosterone via a processive mechanism. Our kinetic data also suggest that the binding of DOC to P450 11B enzymes occurs in at least two distinct steps, favoring an induced-fit mechanism.
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Affiliation(s)
- Juan Valentín-Goyco
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan 48109, United States
- LTC Charles S. Kettles Veterans Affairs Medical Center, 2215 Fuller Road, Ann Arbor, Michigan 48105, United States
| | - Sang-Choul Im
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan 48109, United States
- LTC Charles S. Kettles Veterans Affairs Medical Center, 2215 Fuller Road, Ann Arbor, Michigan 48105, United States
| | - Richard J Auchus
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan 48109, United States
- LTC Charles S. Kettles Veterans Affairs Medical Center, 2215 Fuller Road, Ann Arbor, Michigan 48105, United States
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Kaluzhskiy L, Yablokov E, Gnedenko O, Burkatovskii D, Maslov I, Bogorodskiy A, Ershov P, Tsybruk T, Zelepuga E, Rutckova T, Kozlovskaya E, Dmitrenok P, Gilep A, Borshchevskiy V, Strushkevich N, Ivanov A. The effect of membrane composition on the interaction between human CYP51 and its flavonoid inhibitor - luteolin 7,3'-disulfate. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2024; 1866:184286. [PMID: 38272204 DOI: 10.1016/j.bbamem.2024.184286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/22/2023] [Accepted: 01/16/2024] [Indexed: 01/27/2024]
Abstract
Cytochromes P450 (CYP) are a family of membrane proteins involved in the production of endogenous molecules and the metabolism of xenobiotics. It is well-known that the composition of the membrane can influence the activity and orientation of CYP proteins. However, little is known about how membrane composition affects the ligand binding properties of CYP. In this study, we utilized surface plasmon resonance and fluorescence lifetime analysis to examine the impact of membrane micro-environment composition on the interaction between human microsomal CYP51 (CYP51A1) and its inhibitor, luteolin 7,3'-disulphate (LDS). We observed that membranes containing cholesterol or sphingomyelin exhibited the lowest apparent equilibrium dissociation constant for the CYP51A1-LDS complex. Additionally, the tendency for relation between kinetic parameters of the CYP51A1-LDS complex and membrane viscosity and overall charge was observed. These findings suggest that the specific composition of the membrane, particularly the presence of cholesterol and sphingomyelin, plays a vital role in regulating the interaction between CYP enzymes and their ligands.
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Affiliation(s)
- Leonid Kaluzhskiy
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia.
| | - Evgeniy Yablokov
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia.
| | - Oksana Gnedenko
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia.
| | - Dmitrii Burkatovskii
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia.
| | - Ivan Maslov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia.
| | - Andrey Bogorodskiy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia
| | - Pavel Ershov
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia
| | - Tatsiana Tsybruk
- Institute of Bioorganic Chemistry NASB, 5 Building 2, V.F. Kuprevich Street, 220141 Minsk, Belarus
| | - Elena Zelepuga
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 159 Prospect 100-letiya Vladivostoka, 690022 Vladivostok, Russia.
| | - Tatyana Rutckova
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 159 Prospect 100-letiya Vladivostoka, 690022 Vladivostok, Russia
| | - Emma Kozlovskaya
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 159 Prospect 100-letiya Vladivostoka, 690022 Vladivostok, Russia
| | - Pavel Dmitrenok
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 159 Prospect 100-letiya Vladivostoka, 690022 Vladivostok, Russia.
| | - Andrei Gilep
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia; Institute of Bioorganic Chemistry NASB, 5 Building 2, V.F. Kuprevich Street, 220141 Minsk, Belarus.
| | - Valentin Borshchevskiy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; Joint Institute for Nuclear Research, Dubna 141980, Russia
| | - Natallia Strushkevich
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, 121205 Moscow, Russia.
| | - Alexis Ivanov
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia.
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4
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Sumangala N, Im SC, Valentín-Goyco J, Auchus RJ. Influence of cholesterol on kinetic parameters for human aromatase (P450 19A1) in phospholipid nanodiscs. J Inorg Biochem 2023; 247:112340. [PMID: 37544101 DOI: 10.1016/j.jinorgbio.2023.112340] [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: 03/29/2023] [Revised: 07/20/2023] [Accepted: 07/22/2023] [Indexed: 08/08/2023]
Abstract
Cholesterol, a significant constituent of the endoplasmic reticulum membrane, exerts a substantial effect on the membrane's biophysical and mechanical properties. Cholesterol, however, is often neglected in model systems used to study membrane-bound proteins. For example, the influence of cholesterol on the enzymatic functions of type 2 cytochromes P450, which require a phospholipid bilayer and the redox partner P450-oxidoreductase (POR) for activity, are rarely investigated. Human aromatase (P450 19A1) catalyzes three sequential oxygenations of 19‑carbon steroids to estrogens and is widely expressed across various tissues, which are characterized by varying cholesterol compositions. Our study examined the impact of cholesterol on the functionality of the P450 19A1 complex with POR. Nanodiscs containing P450 19A1 with 20% cholesterol/80% phospholipid had similar rates and affinity of androstenedione binding as phospholipid-only P450 19A1 nanodiscs, and rates of product formation were indistinguishable among these conditions. In contrast, the rate of the first electron transfer from POR to P450 19A1 was 3-fold faster in cholesterol-containing nanodiscs than in phospholipid-only nanodiscs. These results suggest that cholesterol influences some aspects of POR interaction with P450 19A1 and might serve as an additional regulatory mechanism in this catalytic system.
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Affiliation(s)
- Nirupama Sumangala
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, Ann Arbor, MI 48109, USA; Program in Biophysics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Sang-Choul Im
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, Ann Arbor, MI 48109, USA; Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA; Veterans Affairs Medical Center, Ann Arbor, MI 48105, United States
| | - Juan Valentín-Goyco
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, Ann Arbor, MI 48109, USA; Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Richard J Auchus
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, Ann Arbor, MI 48109, USA; Program in Biophysics, University of Michigan, Ann Arbor, MI 48109, USA; Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA; Veterans Affairs Medical Center, Ann Arbor, MI 48105, United States.
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5
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Valentín-Goyco J, Liu J, Peng HM, Oommen J, Auchus RJ. Selectivity of osilodrostat as an inhibitor of human steroidogenic cytochromes P450. J Steroid Biochem Mol Biol 2023; 231:106316. [PMID: 37098354 PMCID: PMC10757358 DOI: 10.1016/j.jsbmb.2023.106316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/20/2023] [Accepted: 04/22/2023] [Indexed: 04/27/2023]
Abstract
Osilodrostat (LCI699) is a potent inhibitor of the human steroidogenic cytochromes P450 11β-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2). LCI699 is FDA-approved for the treatment of Cushing disease, which is characterized by chronic overproduction of cortisol. While phase II and III clinical studies have proven the clinical efficacy and tolerability of LCI699 for treating Cushing disease, few studies have attempted to fully assess the effects of LCI699 on adrenal steroidogenesis. To this end, we first comprehensively analyzed LCI699-mediated inhibition of steroid synthesis in the NCI-H295R human adrenocortical cancer cell line. We then studied LCI699 inhibition using HEK-293 or V79 cells stably expressing individual human steroidogenic P450 enzymes. Our studies using intact cells confirm the potent inhibition of CYP11B1 and CYP11B2 with negligible inhibition of 17-hydroxylase/17,20-lyase (CYP17A1) and 21-hydroxylase (CYP21A2). Furthermore, partial inhibition of the cholesterol side-chain cleavage enzyme (CYP11A1) was observed. To calculate the dissociation constant (Kd) of LCI699 with the adrenal mitochondrial P450 enzymes, we successfully incorporated P450s into lipid nanodiscs and carried out spectrophotometric equilibrium and competition binding assays. Our binding experiments confirm the high affinity of LCI699 to CYP11B1 and CYP11B2 (Kd ≈ 1 nM or less) and much weaker binding for CYP11A1 (Kd = 18.8 μM). Our results confirm the selectivity of LCI699 for CYP11B1 and CYP11B2 and demonstrate partial inhibition of CYP11A1 but not CYP17A1 and CYP21A2.
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Affiliation(s)
- Juan Valentín-Goyco
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, United States; Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, United States; Veterans Affairs Medical Center, 2215 Fuller Road, Building 31, Room 225, Ann Arbor, MI 48105, United States
| | - Jiayan Liu
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, United States
| | - Hwei-Ming Peng
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, United States
| | - Jerry Oommen
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, United States
| | - Richard J Auchus
- Division of Metabolism, Endocrinology, & Diabetes, Department of Internal Medicine, United States; Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, United States; Veterans Affairs Medical Center, 2215 Fuller Road, Building 31, Room 225, Ann Arbor, MI 48105, United States.
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6
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Claahsen - van der Grinten HL, Speiser PW, Ahmed SF, Arlt W, Auchus RJ, Falhammar H, Flück CE, Guasti L, Huebner A, Kortmann BBM, Krone N, Merke DP, Miller WL, Nordenström A, Reisch N, Sandberg DE, Stikkelbroeck NMML, Touraine P, Utari A, Wudy SA, White PC. Congenital Adrenal Hyperplasia-Current Insights in Pathophysiology, Diagnostics, and Management. Endocr Rev 2022; 43:91-159. [PMID: 33961029 PMCID: PMC8755999 DOI: 10.1210/endrev/bnab016] [Citation(s) in RCA: 157] [Impact Index Per Article: 78.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Indexed: 11/19/2022]
Abstract
Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders affecting cortisol biosynthesis. Reduced activity of an enzyme required for cortisol production leads to chronic overstimulation of the adrenal cortex and accumulation of precursors proximal to the blocked enzymatic step. The most common form of CAH is caused by steroid 21-hydroxylase deficiency due to mutations in CYP21A2. Since the last publication summarizing CAH in Endocrine Reviews in 2000, there have been numerous new developments. These include more detailed understanding of steroidogenic pathways, refinements in neonatal screening, improved diagnostic measurements utilizing chromatography and mass spectrometry coupled with steroid profiling, and improved genotyping methods. Clinical trials of alternative medications and modes of delivery have been recently completed or are under way. Genetic and cell-based treatments are being explored. A large body of data concerning long-term outcomes in patients affected by CAH, including psychosexual well-being, has been enhanced by the establishment of disease registries. This review provides the reader with current insights in CAH with special attention to these new developments.
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Affiliation(s)
| | - Phyllis W Speiser
- Cohen Children’s Medical Center of NY, Feinstein Institute, Northwell Health, Zucker School of Medicine, New Hyde Park, NY 11040, USA
| | - S Faisal Ahmed
- Developmental Endocrinology Research Group, School of Medicine Dentistry & Nursing, University of Glasgow, Glasgow, UK
| | - Wiebke Arlt
- Institute of Metabolism and Systems Research (IMSR), College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
- Department of Endocrinology, Queen Elizabeth Hospital, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Richard J Auchus
- Division of Metabolism, Endocrinology, and Diabetes, Departments of Internal Medicine and Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Henrik Falhammar
- Department of Molecular Medicine and Surgery, Karolinska Intitutet, Stockholm, Sweden
- Department of Endocrinology, Karolinska University Hospital, Stockholm, Sweden
| | - Christa E Flück
- Pediatric Endocrinology, Diabetology and Metabolism, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland
| | - Leonardo Guasti
- Centre for Endocrinology, William Harvey Research Institute, Bart’s and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Angela Huebner
- Division of Paediatric Endocrinology and Diabetology, Department of Paediatrics, Universitätsklinikum Dresden, Technische Universität Dresden, Dresden, Germany
| | - Barbara B M Kortmann
- Radboud University Medical Centre, Amalia Childrens Hospital, Department of Pediatric Urology, Nijmegen, The Netherlands
| | - Nils Krone
- Department of Oncology and Metabolism, University of Sheffield, Sheffield, UK
- Department of Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Deborah P Merke
- National Institutes of Health Clinical Center and the Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD 20892, USA
| | - Walter L Miller
- Department of Pediatrics, Center for Reproductive Sciences, and Institute for Human Genetics, University of California, San Francisco, CA 94143, USA
| | - Anna Nordenström
- Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden
- Pediatric Endocrinology, Karolinska University Hospital, Stockholm, Sweden
| | - Nicole Reisch
- Medizinische Klinik IV, Klinikum der Universität München, Munich, Germany
| | - David E Sandberg
- Department of Pediatrics, Susan B. Meister Child Health Evaluation and Research Center, University of Michigan, Ann Arbor, MI 48109, USA
| | | | - Philippe Touraine
- Department of Endocrinology and Reproductive Medicine, Center for Rare Endocrine Diseases of Growth and Development, Center for Rare Gynecological Diseases, Hôpital Pitié Salpêtrière, Sorbonne University Medicine, Paris, France
| | - Agustini Utari
- Division of Pediatric Endocrinology, Department of Pediatrics, Faculty of Medicine, Diponegoro University, Semarang, Indonesia
| | - Stefan A Wudy
- Steroid Research & Mass Spectrometry Unit, Laboratory of Translational Hormone Analytics, Division of Paediatric Endocrinology & Diabetology, Justus Liebig University, Giessen, Germany
| | - Perrin C White
- Division of Pediatric Endocrinology, UT Southwestern Medical Center, Dallas TX 75390, USA
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7
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Brixius-Anderko S, Scott EE. Structural and functional insights into aldosterone synthase interaction with its redox partner protein adrenodoxin. J Biol Chem 2021; 296:100794. [PMID: 34015331 PMCID: PMC8215293 DOI: 10.1016/j.jbc.2021.100794] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/12/2021] [Accepted: 05/14/2021] [Indexed: 01/27/2023] Open
Abstract
Aldosterone is the major mineralocorticoid in the human body controlling blood pressure and salt homeostasis. Overproduction of aldosterone leads to primary aldosteronism, which is the most common form of secondary hypertension with limited treatment options. Production of aldosterone by cytochrome P450 11B2 (CYP11B2, aldosterone synthase) requires two reduction events with the electrons delivered by the iron/sulfur protein adrenodoxin. Very limited information is available about the structural and functional basis of adrenodoxin/CYP11B2 interaction, which impedes the development of new treatment options for primary aldosteronism. A systematic study was carried out to determine if adrenodoxin interaction with CYP11B2 might also have an allosteric component in addition to electron transfer. Indeed, local increases in adrenodoxin concentration promote binding of the substrate 11-deoxycorticosterone and the inhibitor osilodrostat (LCI699) in the active site-over 17 Å away-as well as enhance the inhibitory effect of this latter drug. The CYP11B2 structure in complex with adrenodoxin identified specific residues at the protein-protein interface interacting via five salt bridges and four hydrogen bonds. Comparisons with cholesterol-metabolizing CYP11A1 and cortisol-producing CYP11B1, which also bind adrenodoxin, revealed substantial structural differences in these regions. The structural and functional differences between different P450 interactions with adrenodoxin may provide valuable clues for an orthogonal treatment approach for primary aldosteronism by specifically targeting the interaction between CYP11B2 and adrenodoxin.
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Affiliation(s)
| | - Emily E Scott
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan, USA; Department of Pharmacology, University of Michigan, Ann Arbor, Michigan, USA.
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8
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Child SA, Reddish MJ, Glass SM, Goldfarb MH, Barckhausen IR, Guengerich FP. Functional interactions of adrenodoxin with several human mitochondrial cytochrome P450 enzymes. Arch Biochem Biophys 2020; 694:108596. [PMID: 32980349 DOI: 10.1016/j.abb.2020.108596] [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: 07/06/2020] [Revised: 09/11/2020] [Accepted: 09/12/2020] [Indexed: 12/11/2022]
Abstract
Seven of the 57 human cytochrome P450 (P450) enzymes are mitochondrial and carry out important reactions with steroids and vitamins A and D. These seven P450s utilize an electron transport chain that includes NADPH, NADPH-adrenodoxin reductase (AdR), and adrenodoxin (Adx) instead of the diflavin NADPH-P450 reductase (POR) used by the other P450s in the endoplasmic reticulum. Although numerous studies have been published involving mitochondrial P450 systems, the experimental conditions vary considerably. We compared human Adx and bovine Adx, a commonly used component, and found very similar catalytic activities in reactions catalyzed by human P450s 11B2, 27A1, and 27C1. Binding constants of 6-200 nM were estimated for Adx binding to these P450s using microscale thermophoresis. All P450 catalytic reactions were saturated at 10 μM Adx, and higher concentrations were not inhibitory up to at least 50 μM. Collectively these studies demonstrate the tight binding of Adx (both human and bovine) to AdR and to several mitochondrial P450s and provide guidance for optimization of Adx-dependent P450 reactions.
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Affiliation(s)
- Stella A Child
- The Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, United States
| | - Michael J Reddish
- The Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, United States
| | - Sarah M Glass
- The Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, United States
| | - Margo H Goldfarb
- The Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, United States
| | - Ian R Barckhausen
- The Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, United States
| | - F Peter Guengerich
- The Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, United States.
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9
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Zhang C, Shao H, Li D, Xiao N, Tan Z. Role of tryptophan-metabolizing microbiota in mice diarrhea caused by Folium sennae extracts. BMC Microbiol 2020; 20:185. [PMID: 32600333 PMCID: PMC7325056 DOI: 10.1186/s12866-020-01864-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 06/18/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Although reports have provided evidence that diarrhea caused by Folium sennae can result in intestinal microbiota diversity disorder, the intestinal bacterial characteristic and specific mechanism are still unknown. The objective of our study was to investigate the mechanism of diarrhea caused by Folium sennae, which was associated with intestinal bacterial characteristic reshaping and metabolic abnormality. RESULTS For the intervention of Folium sennae extracts, Chao1 index and Shannon index were statistical decreased. The Beta diversity clusters of mice interfered by Folium sennae extracts were distinctly separated from control group. Combining PPI network analysis, cytochrome P450 enzymes metabolism was the main signaling pathway of diarrhea caused by Folium sennae. Moreover, 10 bacterial flora communities had statistical significant difference with Folium sennae intervention: the abundance of Paraprevotella, Streptococcus, Epulopiscium, Sutterella and Mycoplasma increased significantly; and the abundance of Adlercreutzia, Lactobacillus, Dehalobacterium, Dorea and Oscillospira reduced significantly. Seven of the 10 intestinal microbiota communities were related to the synthesis of tryptophan derivatives, which affected the transformation of aminotryptophan into L-tryptophan, leading to abnormal tryptophan metabolism in the host. CONCLUSIONS Folium sennae targeted cytochrome P450 3A4 to alter intestinal bacterial characteristic and intervene the tryptophan metabolism of intestinal microbiota, such as Streptococcus, Sutterella and Dorea, which could be the intestinal microecological mechanism of diarrhea caused by Folium sennae extracts.
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Affiliation(s)
- Chenyang Zhang
- School of Traditional Chinese Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, China.,Hunan Key Laboratory of TCM Prescription and Syndromes Translational Medicine, Changsha, Hunan, China
| | - Haoqing Shao
- School of Traditional Chinese Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, China.,Hunan Key Laboratory of TCM Prescription and Syndromes Translational Medicine, Changsha, Hunan, China
| | - Dandan Li
- Hunan University of Chinese Medicine, Changsha, Hunan, China
| | - Nenqun Xiao
- Hunan University of Chinese Medicine, Changsha, Hunan, China.
| | - Zhoujin Tan
- Hunan Key Laboratory of TCM Prescription and Syndromes Translational Medicine, Changsha, Hunan, China. .,Hunan University of Chinese Medicine, Changsha, Hunan, China.
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Reddish MJ, Guengerich FP. Human cytochrome P450 11B2 produces aldosterone by a processive mechanism due to the lactol form of the intermediate 18-hydroxycorticosterone. J Biol Chem 2019; 294:12975-12991. [PMID: 31296661 DOI: 10.1074/jbc.ra119.009830] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 07/10/2019] [Indexed: 12/17/2022] Open
Abstract
Human cytochrome P450 (P450) 11B2 catalyzes the formation of aldosterone, the major endogenous human mineralocorticoid. Aldosterone is important for the regulation of electrolyte homeostasis. Mutations and overexpression of P450 11B2 (also known as aldosterone synthase) can lead to hypertension, congestive heart failure, and diabetic nephropathy. The enzyme is therefore a target for drug development to manage these various disorders. P450 11B2 catalyzes aldosterone formation from 11-deoxycorticosterone through three distinct oxidation steps. It is currently unknown to which degree these reactions happen in sequence without the intermediate products dissociating from the enzyme (i.e. processively) or whether these reactions happen solely distributively, in which the intermediate products must first dissociate and then rebind to the enzyme before subsequent oxidation. We present here a comprehensive investigation of processivity in P450 11B2-catalyzed reactions using steady-state, pre-steady-state, pulse-chase, equilibrium-binding titrations, and stopped-flow binding studies. We utilized the data obtained to develop a kinetic model for P450 11B2 and tested this model by enzyme kinetics simulations. We found that although aldosterone is produced processively, the enzyme preferentially utilizes a distributive mechanism that ends with the production of 18-OH corticosterone. This seemingly contradictory observation could be resolved by considering the ability of the intermediate product 18-OH corticosterone to exist as a lactol form, with the equilibrium favoring the ring-closed lactol configuration. In summary, our refined model for P450 11B2 catalysis indicates isomerization of the intermediate to a lactol can explain why P450 11B2 must produce aldosterone through a processive mechanism despite favoring a distributive mechanism.
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Affiliation(s)
- Michael J Reddish
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - F Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146.
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