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Bilyalova A, Bilyalov A, Filatov N, Shagimardanova E, Kiyasov A, Vorontsova M, Gusev O. Non-classical animal models for studying adrenal diseases: advantages, limitations, and implications for research. Lab Anim Res 2024; 40:25. [PMID: 38898483 PMCID: PMC11186145 DOI: 10.1186/s42826-024-00212-8] [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: 03/08/2024] [Revised: 05/24/2024] [Accepted: 06/07/2024] [Indexed: 06/21/2024] Open
Abstract
The study of adrenal disorders is a key component of scientific research, driven by the complex innervation, unique structure, and essential functions of the adrenal glands. This review explores the use of non-traditional animal models for studying congenital adrenal hyperplasia. It highlights the advantages, limitations, and relevance of these models, including domestic ferrets, dogs, guinea pigs, golden hamsters, pigs, and spiny mice. We provide a detailed analysis of the histological structure, steroidogenesis pathways, and genetic characteristics of these animal models. The morphological and functional similarities between the adrenal glands of spiny mice and humans highlight their potential as an important avenue for future research.
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Affiliation(s)
- Alina Bilyalova
- Institute of fundamental medicine and biology, Kazan Federal University, Kazan, 420008, Russia
| | - Airat Bilyalov
- Institute of fundamental medicine and biology, Kazan Federal University, Kazan, 420008, Russia
- Loginov Moscow Clinical Scientific Center, Moscow, 111123, Russia
| | - Nikita Filatov
- Institute of fundamental medicine and biology, Kazan Federal University, Kazan, 420008, Russia
| | - Elena Shagimardanova
- Loginov Moscow Clinical Scientific Center, Moscow, 111123, Russia
- Life Improvement by Future Technologies (LIFT) Center, Moscow, 121205, Russia
| | - Andrey Kiyasov
- Institute of fundamental medicine and biology, Kazan Federal University, Kazan, 420008, Russia
| | | | - Oleg Gusev
- Life Improvement by Future Technologies (LIFT) Center, Moscow, 121205, Russia.
- Intractable Disease Research Center, Graduate School of Medicine, Juntendo University, Tokyo, 113-8421, Japan.
- Endocrinology Research Center, Moscow, 117292, Russia.
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2
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Wróbel TM, Jørgensen FS, Pandey AV, Grudzińska A, Sharma K, Yakubu J, Björkling F. Non-steroidal CYP17A1 Inhibitors: Discovery and Assessment. J Med Chem 2023; 66:6542-6566. [PMID: 37191389 DOI: 10.1021/acs.jmedchem.3c00442] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
CYP17A1 is an enzyme that plays a major role in steroidogenesis and is critically involved in the biosynthesis of steroid hormones. Therefore, it remains an attractive target in several serious hormone-dependent cancer diseases, such as prostate cancer and breast cancer. The medicinal chemistry community has been committed to the discovery and development of CYP17A1 inhibitors for many years, particularly for the treatment of castration-resistant prostate cancer. The current Perspective reflects upon the discovery and evaluation of non-steroidal CYP17A1 inhibitors from a medicinal chemistry angle. Emphasis is placed on the structural aspects of the target, key learnings from the presented chemotypes, and design guidelines for future inhibitors.
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Affiliation(s)
- Tomasz M Wróbel
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances, Faculty of Pharmacy, Medical University of Lublin, Chodźki 4a, 20093 Lublin, Poland
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Flemming Steen Jørgensen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Amit V Pandey
- Pediatric Endocrinology, Department of Pediatrics, University Children's Hospital, Inselspital, Bern and Translational Hormone Research Program, Department of Biomedical Research, University of Bern, Freiburgstrasse 15, 3010 Bern, Switzerland
| | - Angelika Grudzińska
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances, Faculty of Pharmacy, Medical University of Lublin, Chodźki 4a, 20093 Lublin, Poland
| | - Katyayani Sharma
- Pediatric Endocrinology, Department of Pediatrics, University Children's Hospital, Inselspital, Bern and Translational Hormone Research Program, Department of Biomedical Research, University of Bern, Freiburgstrasse 15, 3010 Bern, Switzerland
| | - Jibira Yakubu
- Pediatric Endocrinology, Department of Pediatrics, University Children's Hospital, Inselspital, Bern and Translational Hormone Research Program, Department of Biomedical Research, University of Bern, Freiburgstrasse 15, 3010 Bern, Switzerland
| | - Fredrik Björkling
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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3
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Gabai G, Mongillo P, Giaretta E, Marinelli L. Do Dehydroepiandrosterone (DHEA) and Its Sulfate (DHEAS) Play a Role in the Stress Response in Domestic Animals? Front Vet Sci 2020; 7:588835. [PMID: 33195624 PMCID: PMC7649144 DOI: 10.3389/fvets.2020.588835] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 09/25/2020] [Indexed: 12/16/2022] Open
Abstract
In animal husbandry, stress is often associated with poor health and welfare. Stress occurs when a physiological control system detects a state of real or presumptive threat to the animal's homeostasis or a failure to control a fitness-critical variable. The definition of stress has mostly relied on glucocorticoids measurement, even though glucocorticoids represent one stress-response system, the hypothalamus-pituitary-adrenocortical axis, which is not precise enough as it is also related to metabolic regulation and activated in non-stressful situations (pleasure, excitement, and arousal). The mammal adrenal can synthesize the androgenic steroid dehydroepiandrosterone (DHEA) and its sulfate metabolite (DHEAS), which have been associated to the stress response in several studies performed mostly in humans and laboratory animals. Although the functions of these steroids are not fully understood, available data suggest their antagonistic effects on glucocorticoids and, in humans, their secretion is affected by stress. This review explores the scientific literature on DHEA and DHEAS release in domestic animals in response to stressors of different nature (inflammatory, physical, or social) and duration, and the extra-adrenal contribution to circulating DHEA. Then, the potential use of DHEA in conjunction with cortisol to improve the definition of the stress phenotype in farmed animals is discussed. Although the focus of this review is on farmed animals, examples from other species are reported when available.
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Affiliation(s)
- Gianfranco Gabai
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, Italy
| | - Paolo Mongillo
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, Italy
| | - Elisa Giaretta
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, Italy
| | - Lieta Marinelli
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, Italy
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Rege J, Garber S, Conley AJ, Elsey RM, Turcu AF, Auchus RJ, Rainey WE. Circulating 11-oxygenated androgens across species. J Steroid Biochem Mol Biol 2019; 190:242-249. [PMID: 30959151 PMCID: PMC6733521 DOI: 10.1016/j.jsbmb.2019.04.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 04/04/2019] [Accepted: 04/05/2019] [Indexed: 11/25/2022]
Abstract
The androgen precursors, dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS) are produced in high amounts by the adrenal cortex primarily in humans and a few other primates. The human adrenal also secretes 11-oxygenated androgens (11-oxyandrogens), including 11β-hydroxyandrostenedione (11OHA4), 11-ketoandrostenedione (11KA4), 11β-hydroxytestosterone (11OHT) and 11-ketotestosterone (11KT), of which 11OHT and 11KT are bioactive androgens. The 11-oxyandrogens, particularly 11KT, have been recognized as biologically important testicular androgens in teleost fishes for decades, but their physiological contribution in humans has only recently been established. Beyond fish and humans, however, the presence of 11-oxyandrogens in other species has not been investigated. This study provides a comprehensive analysis of a set of C19 steroids, including the traditional androgens and 11-oxyandrogens, across 18 animal species. As previously shown, serum DHEA and DHEAS were much higher in primates than all other species. Circulating 11-oxyandrogens, especially 11KT, were observed in notable amounts in male, but not in female trout, consistent with gonadal origin in fish. The circulating concentrations of 11-oxyandrogens ranged from 0.1 to 10 nM in pigs, guinea pigs and in all the primates studied (rhesus macaque, baboon, chimpanzee and human) but not in rats or mice, and 11OHA4 was consistently the most abundant. In contrast to fish, serum 11KT concentrations were similar in male and female primates for each species, despite significantly higher circulating testosterone in males, suggesting that 11KT production in these species is not testis-dependent and primarily originates from adrenal-derived 11-oxyandrogen precursors.
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Affiliation(s)
- Juilee Rege
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, United States
| | - Scott Garber
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, United States
| | - Alan J Conley
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California-Davis, Davis, CA, United States
| | - Ruth M Elsey
- Louisiana Department of Wildlife and Fisheries, Rockefeller Wildlife Refuge, Grand Chenier, LA, United States
| | - Adina F Turcu
- Division of Metabolism, Endocrinology, and Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States
| | - Richard J Auchus
- Division of Metabolism, Endocrinology, and Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States; Department of Pharmacology, University of Michigan, Ann Arbor, MI, United States
| | - William E Rainey
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, United States; Division of Metabolism, Endocrinology, and Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States.
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5
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Schiffer L, Arlt W, Storbeck KH. Intracrine androgen biosynthesis, metabolism and action revisited. Mol Cell Endocrinol 2018; 465:4-26. [PMID: 28865807 PMCID: PMC6565845 DOI: 10.1016/j.mce.2017.08.016] [Citation(s) in RCA: 130] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 08/28/2017] [Accepted: 08/28/2017] [Indexed: 12/19/2022]
Abstract
Androgens play an important role in metabolic homeostasis and reproductive health in both men and women. Androgen signalling is dependent on androgen receptor activation, mostly by testosterone and 5α-dihydrotestosterone. However, the intracellular or intracrine activation of C19 androgen precursors to active androgens in peripheral target tissues of androgen action is of equal importance. Intracrine androgen synthesis is often not reflected by circulating androgens but rather by androgen metabolites and conjugates. In this review we provide an overview of human C19 steroid biosynthesis including the production of 11-oxygenated androgens, their transport in circulation and uptake into peripheral tissues. We conceptualise the mechanisms of intracrinology and review the intracrine pathways of activation and inactivation in selected human tissues. The contribution of liver and kidney as organs driving androgen inactivation and renal excretion are also highlighted. Finally, the importance of quantifying androgen metabolites and conjugates to assess intracrine androgen production is discussed.
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Affiliation(s)
- Lina Schiffer
- Institute of Metabolism and Systems Research, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Wiebke Arlt
- Institute of Metabolism and Systems Research, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
| | - Karl-Heinz Storbeck
- Institute of Metabolism and Systems Research, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
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6
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Sushko TA, Gilep AA, Yantsevich AV, Usanov SA. Role of microsomal steroid hydroxylases in Δ7-steroid biosynthesis. BIOCHEMISTRY (MOSCOW) 2013; 78:282-9. [PMID: 23586722 DOI: 10.1134/s0006297913030103] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
CYP17 (steroid 17α-hydroxylase/17,20-lyase) is a key enzyme in steroid hormone biosynthesis. It catalyzes two independent reactions at the same active center and has a unique ability to differentiate Δ(4)-steroids and Δ(5)-steroids in the 17,20-lyase reaction. The present work presents a complex experimental analysis of the role of CYP17 in the metabolism of 7-dehydrosteroids. The data indicate the existence of a possible alternative pathway of steroid hormone biosynthesis using 7-dehydrosteroids. The major reaction products of CYP17 catalyzed hydroxylation of 7-dehydropregnenolone have been identified. Catalytic activity of CYP17 from different species with 7-dehydropregnenolone has been estimated. It is shown that CYP21 cannot use Δ(5)-Δ(7) steroids as a substrate.
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Affiliation(s)
- T A Sushko
- Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus, Minsk, Belarus.
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7
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At the crossroads of steroid hormone biosynthesis: the role, substrate specificity and evolutionary development of CYP17. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2010; 1814:200-9. [PMID: 20619364 DOI: 10.1016/j.bbapap.2010.06.021] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 05/28/2010] [Accepted: 06/26/2010] [Indexed: 11/22/2022]
Abstract
Cytochrome P450s play critical roles in the metabolism of various bioactive compounds. One of the crucial functions of cytochrome P450s in Chordata is in the biosynthesis of steroid hormones. Steroid 17alpha-hydroxylase/17,20-lyase (CYP17) is localized in endoplasmic reticulum membranes of steroidogenic cells. CYP17 catalyzes the 17alpha-hydroxylation reaction of delta4-C₂₁ steroids (progesterone derivatives) and delta5-C₂₁ steroids (pregnenolone derivatives) as well as the 17,20-lyase reaction producing C₁₉-steroids, a key branch point in steroid hormone biosynthesis. Depending on CYP17 activity, the steroid hormone biosynthesis pathway is directed to either the formation of mineralocorticoids and glucocorticoids or sex hormones. In the present review, the current information on CYP17 is analyzed and discussed.
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8
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Wang YH, Tee MK, Miller WL. Human cytochrome p450c17: single step purification and phosphorylation of serine 258 by protein kinase a. Endocrinology 2010; 151:1677-84. [PMID: 20160131 PMCID: PMC2850244 DOI: 10.1210/en.2009-1247] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Cytochrome P450c17 (P450c17) is the single microsomal enzyme that catalyzes steroid 17alpha-hydroxylase and 17,20 lyase activities. The ratio of lyase to hydroxylase activity of human P450c17 determines whether steroidogenesis leads to the synthesis of cortisol or sex steroids. This ratio is regulated posttranslationally by factors that influence the efficiency of electron transfer from P450 oxidoreductase to P450c17. One factor favoring more efficient electron transfer and 17,20 lyase activity is cAMP-dependent serine/threonine phosphorylation of P450c17. Identifying the responsible kinase(s) and the P450c17 residues that undergo phosphorylation has been challenging, partly because of difficulties in preparing biochemically useful amounts of pure, catalytically active P450c17. We describe a modified strategy for preparing P450c17 in which the traditional carboxy-terminal 4xHis tag is replaced by 3xGly6xHis. This construct permits more rotational freedom of the protein when bound to the nickel affinity column, reducing steric associations between the protein and the column, and permitting a single-step chromatographic purification to apparent homogeneity. Using this vector, we explored P450c17 phosphorylation by mutagenesis of Ser and/or Thr residues to Asp or Glu to mimic the approximate size and charge of phospho-Ser or phospho-Thr. This strategy did not identify Ser and/or Thr site(s) that increase the ratio of lyase to hydroxylase activity, suggesting that the regulatory phosphorylation strategy of human P450c17 is very complicated. Although previous work has excluded protein kinase A (PKA) as the responsible kinase, the cAMP-inducible nature of the phosphorylation-associated increase in lyase activity suggests that PKA may play a role, possibly as a priming kinase. Using our novel vector and a series of mutations, we identified the P450c17 site phosphorylated by PKA as Ser258.
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Affiliation(s)
- Yue-Hao Wang
- Professor of Pediatrics and Chief of Endocrinology, HSE 1427, University of California, San Francisco, San Francisco, California 94143-0978, USA
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9
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Sex differences in the excretion of fecal glucocorticoid metabolites in the Syrian hamster. J Comp Physiol B 2010; 180:919-25. [DOI: 10.1007/s00360-010-0467-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2009] [Revised: 03/07/2010] [Accepted: 03/08/2010] [Indexed: 10/19/2022]
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10
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Soma KK, Scotti MAL, Newman AEM, Charlier TD, Demas GE. Novel mechanisms for neuroendocrine regulation of aggression. Front Neuroendocrinol 2008; 29:476-89. [PMID: 18280561 DOI: 10.1016/j.yfrne.2007.12.003] [Citation(s) in RCA: 159] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2007] [Revised: 10/02/2007] [Accepted: 12/25/2007] [Indexed: 11/19/2022]
Abstract
In 1849, Berthold demonstrated that testicular secretions are necessary for aggressive behavior in roosters. Since then, research on the neuroendocrinology of aggression has been dominated by the paradigm that the brain receives gonadal hormones, primarily testosterone, which modulate relevant neural circuits. While this paradigm has been extremely useful, recent studies reveal important alternatives. For example, most vertebrate species are seasonal breeders, and many species show aggression outside of the breeding season, when gonads are regressed and circulating testosterone levels are typically low. Studies in birds and mammals suggest that an adrenal androgen precursor-dehydroepiandrosterone (DHEA)-may be important for the expression of aggression when gonadal testosterone synthesis is low. Circulating DHEA can be metabolized into active sex steroids within the brain. Another possibility is that the brain can autonomously synthesize sex steroids de novo from cholesterol, thereby uncoupling brain steroid levels from circulating steroid levels. These alternative neuroendocrine mechanisms to provide sex steroids to specific neural circuits may have evolved to avoid the "costs" of high circulating testosterone during particular seasons. Physiological indicators of season (e.g., melatonin) may allow animals to switch from one neuroendocrine mechanism to another across the year. Such mechanisms may be important for the control of aggression in many vertebrate species, including humans.
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Affiliation(s)
- Kiran K Soma
- Department of Psychology, Graduate Program in Neuroscience, University of British Columbia, Vancouver, BC, Canada V6T 1Z4.
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11
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Yang WH, Hammes SR. Xenopus laevis CYP17 regulates androgen biosynthesis independent of the cofactor cytochrome b5. J Biol Chem 2005; 280:10196-201. [PMID: 15640159 PMCID: PMC1513634 DOI: 10.1074/jbc.m411886200] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The enzyme CYP17 primarily regulates androgen production by mediating four reactions: conversion of pregnenolone and progesterone to 17-hydroxypregnenolone and 17-hydroxyprogesterone, respectively (17alpha-hydroxylase activity), followed by conversion of the 17-hydroxylated steroids to dehydroepiandrosterone and androstenedione, respectively (17,20-lyase activity). Most mammalian CYP17 isoforms have high 17alpha-hydroxylase relative to 17,20-lyase activities and preferentially mediate one of the two 17,20-lyase reactions. In contrast, Xenopus laevis CYP17 potently regulates all four reactions in the frog ovary. CYP17 isoforms generally rely on the cofactor cytochrome b(5) for the 17,20-lyase reaction, suggesting that the high lyase activity of Xenopus CYP17 might be due to a lesser dependence on b(5). The kinetics of Xenopus CYP17 expressed in yeast microsomes were therefore examined in the absence and presence of Xenopus on human b(5). Xenopus CYP17 mediated both 17,20-lyase reactions in the absence of b(5), confirming that the activity did not require b(5). However, both Xenopus and human b(5) slightly enhanced Xenopus CYP17-mediated lyase activity, indicating that the enzyme was still at least partially responsive to b(5). Surprisingly, only the human b(5) cofactor enhanced human CYP17-mediated lyase activity, implying that the human enzyme had more specific cofactor requirements than Xenopus CYP17. Studies using human/Xenopus chimeric b(5) proteins revealed that human b(5) residues 16-41 were important for the specific regulation of the lyase activity of HuCYP17, possibly serving as an interacting domain with the enzyme. CYP17 may therefore have evolved from a general producer of sex steroids in lower vertebrates to a more tightly regulated producer of both sex steroids and glucocorticoids in mammals.
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Affiliation(s)
| | - Stephen R Hammes
- ‡ A W. W. Caruth, Jr. Scholar in Biomedical Research. To whom correspondence should be addressed. University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-8857. Tel.: 214-648-3749; Fax: 214-648-7934; E-mail:
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12
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Yang WH, Lutz LB, Hammes SR. Xenopus laevis ovarian CYP17 is a highly potent enzyme expressed exclusively in oocytes. Evidence that oocytes play a critical role in Xenopus ovarian androgen production. J Biol Chem 2003; 278:9552-9. [PMID: 12522215 DOI: 10.1074/jbc.m212027200] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Progesterone has long been considered the primary mediator of Xenopus oocyte maturation. We have recently shown, however, that androgens, which are equal or more potent promoters of maturation and are present at higher levels in ovulating frogs, may also be playing an important physiologic role in mediating maturation. Here, we examined the role of CYP17, a key enzyme mediating sex steroid synthesis, in Xenopus ovarian androgen production. We found that the 17,20-lyase activities of Xenopus CYP17 exceeded the 17alpha-hydroxylase activities in both the Delta4 and Delta5 pathways; thus, Xenopus CYP17 rapidly converted pregnenolone and progesterone to dehydroepiandrosterone (DHEA) and androstenedione, respectively. This remarkably robust activity exceeds that of CYP17 from most higher vertebrates, and likely explains why virtually no progesterone is detected in ovulating frogs. Additionally, ovarian CYP17 activity was present exclusively in oocytes, although all other enzymes involved in sex steroid production were expressed almost entirely in surrounding follicular cells. This compartmentalization suggests a "two-cell" model whereby Xenopus ovarian androgen production requires both follicular cells and oocytes themselves. The requirement of oocytes for ovarian androgen production further introduces the unusual paradigm whereby germ cells may be responsible for producing important steroids used to mediate their own maturation.
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Affiliation(s)
- Wei-Hsiung Yang
- Department of Internal Medicine, Division of Endocrinology and Metabolism, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8857, USA
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13
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Mathieu AP, LeHoux JG, Auchus RJ. Molecular dynamics of substrate complexes with hamster cytochrome P450c17 (CYP17): mechanistic approach to understanding substrate binding and activities. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1619:291-300. [PMID: 12573489 DOI: 10.1016/s0304-4165(02)00488-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The cytochrome P450c17 isoforms from various animal species have different substrate selectivity, especially for 17,20-lyase activity. In particular, the human P450c17 selectively produces dehydroepiandrosterone with little androstenedione (AD). Hamster P450c17, on the other hand, produces both of these steroids at comparable rates. We thus investigated if computational analysis could explain the difference in activity profiles. Therefore, we inserted the four P450c17 substrates-pregnenolone, progesterone, and their 17alpha-hydroxylated forms-inside our hamster P450c17 model, which we derived from our human P450c17 model based on the crystal structure of P450BMP. We performed molecular dynamics (MD) simulations on the complexes and analyzed the resultant trajectories to identify amino acids that interact with substrates. Starting with substrates in two different orientations, we obtained two sets of binding trajectories in each case. The first set of trajectories reveal structural rearrangements that occur during binding, whereas the second set of trajectories reflects substrate orientations during catalysis. Our modeling suggests that three distinct steps are required for substrate selectivity and binding to the hamster P450c17: (1) recognition of the substrate at the putative substrate entrance, characterized by a pocket at the surface of the hamster P450c17 containing charged residues R96 and D116; (2) entry of the substrate into the active site, in an intermediate position directed by possible hydrogen bonding of the substrates with the heme D-ring propionate group, R96, R440, and T306; followed by (3) 90 degrees counterclockwise rotation of the substrates, positioning them in optimal position for reactivity, a process that may be directed by hydrogen bonding to the 110-112 region of the hamster P450c17. With some substrates, we obtained trajectories which suggest that major distortions in the I-helix and opening of the H-I loop occur during substrate binding. In conclusion, these modeling exercises provide insight to possible structural reorganizations that occur during substrate binding and suggest that amino acids that participate in three distinct steps of this process may all contribute to substrate binding and activity.
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Affiliation(s)
- Axel P Mathieu
- Department of Biochemistry, Faculty of Medicine, University of Sherbrooke, QC, J1H 5N4, Sherbrooke, Canada
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14
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Mathieu AP, Auchus RJ, LeHoux JG. Comparison of the hamster and human adrenal P450c17 (17 alpha-hydroxylase/17,20-lyase) using site-directed mutagenesis and molecular modeling. J Steroid Biochem Mol Biol 2002; 80:99-107. [PMID: 11867269 DOI: 10.1016/s0960-0760(01)00172-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
In order to understand the activity specificity of the hamster cytochrome P450 17 alpha-hydroxylase/17,20-lyase (P450c17), we have studied its structure/activity using three hamster P450c17 recombinant mutants (T202N/D240N/D407H). In transiently transfected COS-1 cells, the mutation T202N reduced 17 alpha-hydroxylation of pregnenolone and progesterone to 24 and 44% of wild type (WT), respectively, followed by reduced 17,20-cleavage to 71 and 67%, respectively. On the other hand, the mutation D240N decreased specifically 17,20-lyase activity to 61% of WT when incubated with pregnenolone while the mutation D407H only decreased 17 alpha-hydroxylation to 46% when incubated with progesterone.To comprehend the altered activity profiles of these hamster P450c17 mutants, we have elaborated a 3D model of the hamster P450c17 and compared it to our preceding model of the human P450c17. Analysis of the mutants with this model showed that, without direct contact to the substrates, these mutations transmit structural changes to the active site. By analogy, these results support the concept that any cellular changes modifying the external structure of P450c17, such as phosphorylation, could have influence on its active site and enzymatic activities.
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Affiliation(s)
- Axel P Mathieu
- Department of Biochemistry, Faculty of Medicine, University of, Sherbrooke, Que., Canada J1H 5N4
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15
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Mathieu AP, Auchus RJ, LeHoux JG. Molecular modeling of the hamster adrenal P450C17. Endocr Res 2000; 26:723-8. [PMID: 11196448 DOI: 10.3109/07435800009048592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The cytochrome P450C17 (C17) is the steroidogenic enzyme responsible for the conversion of pregnenolone and progesterone to dehydroepiandrosterone (DHEA) and delta4-androstenedione (AD) respectively. This conversion is achieved by two enzymatic activities, 17alpha-hydroxylase and 17,20-lyase, located at the same active site. In man, the adrenal C17 basically only produces DHEA. We have shown that the hamster adrenal C17 produces DHEA as well as AD. Moreover, the hamster like man produces cortisol as its major glucocorticoid. We can thus compare the hamster and human adrenal C17, and use their differences in order to elaborate a strategy for structure-function studies. We have thus engineered hamster adrenal C17 mutants which possess modified enzymatic activities. We also proceeded to elaborate a three-dimensional model of the hamster C17 to visualise the structural impact of these mutations. This model demonstrates that the mutations created are not localised at the active site, but rather in surrounding regions. These could affect the conformation of the active site, in turn, modulating the 17alpha-hydroxylase and 17,20-lyase activities. For example, the mutation T202N is located next to Val 482 and Val 483 which compose the roof of the active site. This mutation decreased both 17alpha-hydroxylase and 17,20-lyase activities, indicating the importance of the roof of the active site for general functionality of the C17.
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Affiliation(s)
- A P Mathieu
- Department of Biochemistry, Faculty of Medicine, University of Sherbrooke, Quebec, Canada
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Pieper DR, Lobocki CA. Characterization of serum dehydroepiandrosterone secretion in golden hamsters. PROCEEDINGS OF THE SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE. SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE (NEW YORK, N.Y.) 2000; 224:278-84. [PMID: 10964263 DOI: 10.1046/j.1525-1373.2000.22432.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Dehydroepiandrosterone (DHEA) is an adrenal androgen whose function is poorly understood. Although DHEA and DHEA sulfate (DHEAS) are secreted in relatively high quantities by the human adrenal, the laboratory rat secretes very little, thus hindering experimental studies of the hormone. In this paper, we measured the changes in serum DHEA and DHEAS under various physiological conditions in golden hamsters. Evening serum DHEAS fell from 6.30 +/- 0.78 microg/dl (mean +/- SE) before surgery to 3.03 +/- 0.23 microg/dl 12 days after bilateral adrenalectomy. Hamsters had higher levels of DHEA and DHEAS in the evening than in the morning, but removal of the gonads did not consistently decrease serum DHEA or DHEAS in males or females. Evening levels of DHEA and DHEAS reached a peak around 7 weeks of age and then gradually decreased to about one-third of these levels by one year of age. These results suggest that DHEA and DHEAS are secreted at least in part from the hamster adrenal, that they do not originate from the gonads, and that there is a daily rhythm with peak levels at a time of day just preceding the active phase. In addition, the levels of these hormones decrease with aging.
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Affiliation(s)
- D R Pieper
- St. John Hospital, Detroit, Michigan 48236; and Providence Hospital, Southfield, Michigan 48037, USA.
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Brock BJ, Waterman MR. The use of random chimeragenesis to study structure/function properties of rat and human P450c17. Arch Biochem Biophys 2000; 373:401-8. [PMID: 10620365 DOI: 10.1006/abbi.1999.1557] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The microsomal 17alpha-hydroxylase/17,20-lyase cytochrome P450 (P450c17) catalyzes the 17alpha-hydroxylase reaction required to produce cortisol, the major glucocorticoid in many species and the 17,20-lyase activity required for the production of androgens in all species. Utilizing the technique of random chimeragenesis we have attempted to map regions of primary sequence that contribute to the species-specific biochemical differences between rat and human P450c17. We have previously reported significant differences between rat and human P450c17 in their activities, stability and substrate-dependent coupling efficiencies even though they share 68% amino acid identity. Identification of the regions of primary sequence that contribute to each of these properties would be helpful in understanding the structure/function relationships in this enzyme. A single plasmid containing the cDNAs encoding both enzymes in a tandem orientation was constructed. This plasmid was linearized at unique restriction sites and used to transform Escherichia coli. A three-step screening protocol identified five chimeras with a uniform distribution of 5' rat and 3' human sequence. All chimeric proteins yield the characteristic reduced-CO difference spectra, indicating proper folding. The chimeras exhibit a range of stability and activities that are not consistent with the degree of parental primary sequence. A chimera containing 301 N-terminal rat P450c17 amino acids and lacking the rat P450c17 phenylalanine 343, had the highest lyase activity. Generation of these functional rat/human chimeras suggests that the tertiary structures of rat and human P450c17 are sufficiently conserved to allow proper folding of chimeric enzymes. However, the properties of these chimeras did not permit identification of a region of primary sequence that contributes to a species-specific property of rat and human P450c17. Stability of these chimeras and insight into the presence of secondary structural elements is discussed.
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Affiliation(s)
- B J Brock
- Department of Biochemistry, Vanderbilt University School of Medicine, 607 Light Hall, 23rd and Pierce Avenue, Nashville, Tennessee 37232-0146, USA
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Pieper DR, Lobocki CA, Lichten EM, Malaczynski J. Dehydroepiandrosterone and exercise in golden hamsters. Physiol Behav 1999; 67:607-10. [PMID: 10549900 DOI: 10.1016/s0031-9384(99)00108-0] [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: 10/17/2022]
Abstract
Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) are adrenal androgens that have been associated with a sense of well-being in humans. We describe two experiments done to test the hypothesis that an increase in DHEA or DHEAS secretion is associated with the inclination to exercise using a hamster model. In the first experiment, morning blood samples were obtained from adult male golden hamsters at various intervals after being placed in cages with (EX group) or without (SED group) access to running wheels. The EX group had lower DHEA (6, 12, and 14 weeks; p < 0.05) and DHEAS (13 and 16 weeks; p < 0.01) levels than the SED hamsters. In the second experiment, the number of wheel revolutions was monitored in castrated adult male hamsters implanted with Silastic capsules containing no hormone (blank control group), testosterone, or DHEA. The number of wheel revolutions in the group receiving DHEA was not significantly different than the blank control group, whereas testosterone increased wheel running at 4, 5, and 7 weeks (p < 0.05). These results indicate that DHEA and DHEAS levels decrease with exercise in male golden hamsters and that exogenous DHEA does not enhance the tendency to run on wheels.
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Affiliation(s)
- D R Pieper
- Providence Hospital, Southfield, MI 48037, USA.
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Brock BJ, Waterman MR. Biochemical differences between rat and human cytochrome P450c17 support the different steroidogenic needs of these two species. Biochemistry 1999; 38:1598-606. [PMID: 9931027 DOI: 10.1021/bi9821059] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Microsomal 17alpha-hydroxylase/17,20-lyase cytochrome P450 (P450c17) catalyzes both the 17alpha-hydroxylase reaction required to produce cortisol, the major glucocorticoid in many animals, and the 17, 20-lyase activity required for the production of androgens in all animals. In rodents such as rat, which utilize corticosterone as the major glucocorticoid, P450c17 is expressed predominantly in the gonads, and is absent in the adrenal. In other species including humans, P450c17 is expressed in both adrenal and gonads and participates in both glucocorticoid and androgen production. Rat and human forms of P450c17 are 69% identical at the amino acid level. Based on the differences in physiological roles between P450c17 in these two species, it could be predicted that major differences would be observed in their hydroxylase activities. Contrary to this hypothesis, using partially purified, recombinant human and rat P450c17, we found that the most significant differences lie in their lyase activities. Lyase activities demonstrate that the rat enzyme favors Delta4 (progesterone) substrates while the human enzyme favors Delta5 (pregnenolone) substrates. This substrate preference is also observed in the ability of steroids to decrease uncoupled H2O2 production and to increase stability during turnover. Cytochrome b5, a microsomal electron-transfer protein, enhances lyase activities of rat and human P450c17. However, the most dramatic stimulatory effect is on the human HO-PROG lyase activity. This enhancement of activities is not associated with electron transfer. These differences in biochemical properties between the two forms of P450c17 indicate that human P450c17 has evolved as an enzyme system that limits androgen production to the gonads where a favorable b5:P450c17 ratio exists. Even though orthologous forms of P450c17 are capable of catalyzing the same enzymatic activities, specific physiological requirements of each species ensure biochemical differences between these enzymes.
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Affiliation(s)
- B J Brock
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, USA
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Abstract
The hyperandrogenism of polycystic ovary syndrome (PCOS) appears to be due to dysregulation of steroidogenesis within the ovaries and adrenal glands. P450c17 is the key enzyme that regulates androgen synthesis. It is the only enzyme known to have the capacity to convert C21-precursors to the androgen pre-hormones, the 17-ketosteroids. It is a single enzyme with two activities, 17-hydroxylase and 17,20-lyase. Thus, its regulation is a significant factor in the expression of hyperandrogenism. Androgen secretion is LH-dependent in the ovary and ACTH-dependent in the adrenal glands. The androgenic response to each of these tropic hormones seems to be modulated by intra-ovarian or intra-adrenal autocrine and paracrine mechanisms. This modulation serves to regulate steroid hormone secretion in tissue-specific ways. Insulin, IGFs and inhibin are among the many growth factors capable of augmenting the response to LH and ACTH. The insulin/IGF system stimulates P450c17 mRNA expression and activities in the ovaries and adrenal glands. An integrating link between insulin resistance and hyperandrogenemia may be serine phosphorylation, which inhibits activity of the insulin receptor and promotes the 17,20-lyase activity of P450c17. However, it must be kept in mind that there is some evidence for the existence of P450c17-independent pathways of androgen biosynthesis.
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Affiliation(s)
- K N Qin
- The University of Chicago, Pritzker School of Medicine, The University of Chicago Children's Hospital, IL 60637-1470, USA
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Brière N, Martel D, Cloutier M, LeHoux JG. Immunolocalization and biochemical determination of cytochrome P450C17 in adrenals of hamsters treated with ACTH. J Histochem Cytochem 1997; 45:1409-16. [PMID: 9313802 DOI: 10.1177/002215549704501009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
We used an anti-rat adrenal cytochrome P450C17 (P450C17) antibody to perform immunofluorescence and also immunogold electron microscopic studies to determine the zonal and intracellular distribution of P450C17 in hamster adrenals. Because P450C17 activity is regulated mainly by adrenocorticotropin (ACTH), its zonal and intracellular localization was also analyzed after ACTH treatment. The effect of ACTH treatment on protein concentration was also investigated by Western blotting analysis. By immunofluorescence, we found P450C17 to be confined to the zona fasciculata (ZF) in the hamster, in contrast to other small rodents, which do not express P450C17 in their adrenals. After treatment with ACTH, the thickness of the ZF remained unchanged compared to that of control animals, whereas a marked increase in fluorescence intensity was observed. In addition, dispersed cells in the zona reticularis (ZR) showed positive staining after ACTH treatment. Immunocytochemistry with colloidal gold showed P450C17 to be localized and importantly increased only in the cytoplasmic areas between the mitochondria of ZF cells of ACTH-treated animals. These areas are predominantly occupied by elements of the endoplasmic reticulum and other unidentified organelles. Immunoblotting analysis of whole glands revealed a single protein band at approximately 55 kD, which reacted with the 450C17 antibody. After stimulation with ACTH injected at 5-hr intervals over a period of 20 hr, P450C17 protein concentrations were considerably greater than in control animals. In conclusion, P450C17 is located not over mitochondria but probably in the endoplasmic reticulum of the ZF cells in hamster adrenals. Treatment with ACTH induced expression of cytochrome P450C17 in ZF cells, increasing its production in these cells without stimulating cell proliferation.
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Affiliation(s)
- N Brière
- Department of Biochemistry, Faculty of Medicine, University of Sherbrooke, Quebec, Canada
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