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Nuclear Receptors as Regulators of Pituitary Corticotroph Pro-Opiomelanocortin Transcription. Cells 2020; 9:cells9040900. [PMID: 32272677 PMCID: PMC7226830 DOI: 10.3390/cells9040900] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 03/29/2020] [Accepted: 04/01/2020] [Indexed: 12/16/2022] Open
Abstract
The hypothalamic–pituitary–adrenal (HPA) axis plays a critical role in adaptive stress responses and maintaining organism homeostasis. The pituitary corticotroph is the central player in the HPA axis and is regulated by a plethora of hormonal and stress related factors that synergistically interact to activate and temper pro-opiomelanocortin (POMC) transcription, to either increase or decrease adrenocorticotropic hormone (ACTH) production and secretion as needed. Nuclear receptors are a family of highly conserved transcription factors that can also be induced by various physiologic signals, and they mediate their responses via multiple targets to regulate metabolism and homeostasis. In this review, we summarize the modulatory roles of nuclear receptors on pituitary corticotroph cell POMC transcription, describe the unique and complex role these factors play in hypothalamic–pituitary–adrenal axis (HPA) regulation and discuss potential therapeutic targets in disease states.
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Affiliation(s)
- Kimberly D Barnash
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Lindsey I James
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Stephen V Frye
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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3
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Mazaira GI, Zgajnar NR, Lotufo CM, Daneri-Becerra C, Sivils JC, Soto OB, Cox MB, Galigniana MD. The Nuclear Receptor Field: A Historical Overview and Future Challenges. NUCLEAR RECEPTOR RESEARCH 2018; 5:101320. [PMID: 30148160 PMCID: PMC6108593 DOI: 10.11131/2018/101320] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
In this article we summarize the birth of the field of nuclear receptors, the discovery of untransformed and transformed isoforms of ligand-binding macromolecules, the discovery of the three-domain structure of the receptors, and the properties of the Hsp90-based heterocomplex responsible for the overall structure of the oligomeric receptor and many aspects of the biological effects. The discovery and properties of the subfamily of receptors called orphan receptors is also outlined. Novel molecular aspects of the mechanism of action of nuclear receptors and challenges to resolve in the near future are discussed.
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Affiliation(s)
- Gisela I. Mazaira
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (1428), Argentina
| | - Nadia R. Zgajnar
- Instituto de Biología y Medicina Experimental- CONICET. Buenos Aires (1428), Argentina
| | - Cecilia M. Lotufo
- Instituto de Biología y Medicina Experimental- CONICET. Buenos Aires (1428), Argentina
| | | | - Jeffrey C. Sivils
- Department of Biological Sciences and Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX 79968, USA
| | - Olga B. Soto
- Department of Biological Sciences and Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX 79968, USA
| | - Marc B. Cox
- Department of Biological Sciences and Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX 79968, USA
| | - Mario D. Galigniana
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (1428), Argentina
- Instituto de Biología y Medicina Experimental- CONICET. Buenos Aires (1428), Argentina
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4
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Abstract
The nuclear receptor superfamily includes many receptors, identified based on their similarity to steroid hormone receptors but without a known ligand. The study of how these receptors are diversely regulated to interact with genomic regions to control a plethora of biological processes has provided critical insight into development, physiology, and the molecular pathology of disease. Here we provide a compendium of these so-called orphan receptors and focus on what has been learned about their modes of action, physiological functions, and therapeutic promise.
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Affiliation(s)
- Shannon E Mullican
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, and The Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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5
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Watson PJ, Fairall L, Schwabe JW. Nuclear hormone receptor co-repressors: structure and function. Mol Cell Endocrinol 2012; 348:440-9. [PMID: 21925568 PMCID: PMC3315023 DOI: 10.1016/j.mce.2011.08.033] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Revised: 08/17/2011] [Accepted: 08/25/2011] [Indexed: 01/22/2023]
Abstract
Co-repressor proteins, such as SMRT and NCoR, mediate the repressive activity of unliganded nuclear receptors and other transcription factors. They appear to act as intrinsically disordered "hub proteins" that integrate the activities of a range of transcription factors with a number of histone modifying enzymes. Although these co-repressor proteins are challenging targets for structural studies due to their largely unstructured character, a number of structures have recently been determined of co-repressor interaction regions in complex with their interacting partners. These have yielded considerable insight into the mechanism of assembly of these complexes, the structural basis for the specificity of the interactions and also open opportunities for targeting these interactions therapeutically.
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Vinayavekhin N, Saghatelian A. Discovery of a protein-metabolite interaction between unsaturated fatty acids and the nuclear receptor Nur77 using a metabolomics approach. J Am Chem Soc 2011; 133:17168-71. [PMID: 21973308 PMCID: PMC4569094 DOI: 10.1021/ja208199h] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Neuron-derived clone 77 (Nur77) is an orphan nuclear receptor with currently no known natural ligands. Here we applied a metabolomics platform for detecting protein-metabolite interactions (PMIs) to identify lipids that bind to Nur77. Using this approach, we discovered that the Nur77 ligand-binding domain (Nur77LBD) enriches unsaturated fatty acids (UFAs) in tissue lipid mixtures. The interaction of Nur77 with arachidonic acid and docosahexaenoic acid was subsequently characterized using a number of biophysical and biochemical assays. Together these data indicate that UFAs bind to Nur77LBD to cause changes in the conformation and oligomerization of the receptor. UFAs are the only endogenous lipids reported to bind to Nur77, which highlights the use of metabolomics in the discovery of novel PMIs.
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Affiliation(s)
- Nawaporn Vinayavekhin
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138
| | - Alan Saghatelian
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138
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7
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Edwards AM, Isserlin R, Bader GD, Frye SV, Willson TM, Yu FH. Too many roads not taken. Nature 2011; 470:163-5. [PMID: 21307913 DOI: 10.1038/470163a] [Citation(s) in RCA: 281] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Aled M Edwards
- University of Toronto, Toronto, Ontario M5G 1L7, Canada.
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8
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Jin L, Li Y. Structural and functional insights into nuclear receptor signaling. Adv Drug Deliv Rev 2010; 62:1218-26. [PMID: 20723571 DOI: 10.1016/j.addr.2010.08.007] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2010] [Revised: 08/08/2010] [Accepted: 08/10/2010] [Indexed: 01/14/2023]
Abstract
Nuclear receptors are important transcriptional factors that share high sequence identity and conserved domains, including a DNA-binding domain (DBD) and a ligand-binding domain (LBD). The LBD plays a crucial role in ligand-mediated nuclear receptor activity. Hundreds of different crystal structures of nuclear receptors have revealed a general mechanism for the molecular basis of ligand binding and ligand-mediated regulation of nuclear receptors. Despite the conserved fold of nuclear receptor LBDs, the ligand-binding pocket is the least conserved region among different nuclear receptor LBDs. Structural comparison and analysis show that several features of the pocket, like the size and also the shape, have contributed to the ligand binding affinity and specificity. In addition, the plastic nature of the ligand-binding pockets in many nuclear receptors provides greater flexibility to further accommodate specific ligands with a variety of conformations. Nuclear receptor coactivators usually contain multiple LXXLL motifs that are used to interact with nuclear receptors. The nuclear receptors respond differently to distinct ligands and readily exchange their ligands in different environments. The conformational flexibility of the AF-2 helix allows the nuclear receptor to sense the presence of the bound ligands, either an agonist or an antagonist, and to recruit the coactivators or corepressors that ultimately determine the transcriptional activation or repression of nuclear receptors.
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Edwards AM, Bountra C, Kerr DJ, Willson TM. Open access chemical and clinical probes to support drug discovery. Nat Chem Biol 2009; 5:436-40. [PMID: 19536100 DOI: 10.1038/nchembio0709-436] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Drug discovery resources in academia and industry are not used efficiently, to the detriment of industry and society. Duplication could be reduced, and productivity could be increased, by performing basic biology and clinical proofs of concept within open access industry-academia partnerships. Chemical biologists could play a central role in this effort.
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Affiliation(s)
- Aled M Edwards
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada.
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10
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Wu SC, Zhang Y. Minireview: role of protein methylation and demethylation in nuclear hormone signaling. Mol Endocrinol 2009; 23:1323-34. [PMID: 19407220 DOI: 10.1210/me.2009-0131] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Nuclear hormone receptors (NRs) are transcription factors responsible for mediating the biological effects of hormones during development, metabolism, and homeostasis. Induction of NR target genes is accomplished through the assembly of hormone-bound NR complexes at target promoters and coincides with changes in histone modifications that promote transcription. Some coactivators and corepressors of NR can enhance or inhibit NR function by covalently modifying histones. One such modification is methylation, which plays important roles in transcriptional regulation. Histone methylation is catalyzed by histone methyltransferases and reversed by histone demethylases. Recent studies have uncovered the importance of these enzymes in the regulation of NR target genes. In addition to histones, these enzymes have nonhistone substrates and can methylate and demethylate NRs and coregulatory proteins in order to modulate their function. This review discusses recent progress in our understanding of the role of methylation and demethylation of histones, NRs, and their coregulators in NR-mediated transcription.
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Affiliation(s)
- Susan C Wu
- Howard Hughes Medical Institute, Department of Biochemistry, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7295, USA
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11
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Howarth DL, Law SHW, Barnes B, Hall JM, Hinton DE, Moore L, Maglich JM, Moore JT, Kullman SW. Paralogous vitamin D receptors in teleosts: transition of nuclear receptor function. Endocrinology 2008; 149:2411-22. [PMID: 18258682 PMCID: PMC2329287 DOI: 10.1210/en.2007-1256] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The availability of multiple teleost (bony fish) genomes is providing unprecedented opportunities to understand the diversity and function of gene duplication events using comparative genomics. Here we describe the cloning and functional characterization of two novel vitamin D receptor (VDR) paralogs from the freshwater teleost medaka (Oryzias latipes). VDR sequences were identified through mining of the medaka genome database in which gene organization and structure was determined. Two distinct VDR genes were identified in the medaka genome and mapped to defined loci. Each VDR sequence exhibits unique intronic organization and dissimilar 5' untranslated regions, suggesting they are not isoforms of the same gene locus. Phylogenetic comparison with additional teleosts and mammalian VDR sequences illustrate that two distinct clusters are formed separating aquatic and terrestrial species. Nested within the teleost cluster are two separate clades for VDRalpha and VDRbeta. The topology of teleost VDR sequences is consistent with the notion of paralogous genes arising from a whole genome duplication event prior to teleost radiation. Functional characterization was conducted through the development of VDR expression vectors including Gal4 chimeras containing the yeast Gal4 DNA binding domain fused to the medaka VDR ligand binding domain and full-length protein. The common VDR ligand 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)(2)D(3)] resulted in significant transactivation activity with both the Gal4 and full-length constructs of medaka (m) VDRbeta. Comparatively, transactivation of mVDRalpha with 1alpha,25(OH)(2)D(3) was highly attenuated, suggesting a functional divergence between these two nuclear receptor paralogs. We additionally demonstrate through coactivator studies that mVDRalpha is still functional; however, it exhibits a different sensitivity to 1alpha,25(OH)(2)D(3), compared with VDRbeta. These results suggest that in mVDRalpha and VDRbeta have undergone a functional divergence through a process of sub- and/or neofunctionalization of VDR nuclear receptor gene pairs.
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Affiliation(s)
- Deanna L Howarth
- Integrated Toxicology and Environmental Health Program, Nicholas School of the Environment and Earth Sciences, Duke University, Durham, North Carolina 27708, USA
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Abstract
Until recently, the study of nuclear receptor (NR) function in breast cancer biology has been largely limited to estrogen and progesterone receptors. The development of reliable gene expression arrays, real-time quantitative RT-PCR, and immunohistochemical techniques for studying NR superfamily members in primary human breast cancers has now revealed the presence and potential importance of several additional NRs in the biology of breast cancer. These include receptors for steroid hormones (including androgens and corticosteroids), fat-soluble vitamins A and D, fatty acids, and xenobiotic lipids derived from diet. It is now clear that after NR activation, both genomic and nongenomic NR pathways can coordinately activate growth factor signaling pathways. Advances in our understanding of both NR functional networks and epithelial cell growth factor signaling pathways have revealed a frequent interplay between NR and epithelial cell growth factor family signaling that is clinically relevant to breast cancer. Understanding how growth factor receptors and their downstream kinases are activated by NRs (and vice-versa) is a central goal for maximizing treatment opportunities in breast cancer. In addition to the estrogen receptor, it is predicted that modulating the activity of other NRs will soon provide novel prevention and treatment approaches for breast cancer patients.
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Affiliation(s)
- Suzanne D Conzen
- Department of Medicine, The University of Chicago, MC 2115, Chicago, Illinois 60637, USA.
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Ståhlberg N, Merino R, Hernández LH, Fernández-Pérez L, Sandelin A, Engström P, Tollet-Egnell P, Lenhard B, Flores-Morales A. Exploring hepatic hormone actions using a compilation of gene expression profiles. BMC PHYSIOLOGY 2005; 5:8. [PMID: 15953391 PMCID: PMC1180834 DOI: 10.1186/1472-6793-5-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2004] [Accepted: 06/13/2005] [Indexed: 11/10/2022]
Abstract
Background Microarray analysis is attractive within the field of endocrine research because regulation of gene expression is a key mechanism whereby hormones exert their actions. Knowledge discovery and testing of hypothesis based on information-rich expression profiles promise to accelerate discovery of physiologically relevant hormonal mechanisms of action. However, most studies so-far concentrate on the analysis of actions of single hormones and few examples exist that attempt to use compilation of different hormone-regulated expression profiles to gain insight into how hormone act to regulate tissue physiology. This report illustrates how a meta-analysis of multiple transcript profiles obtained from a single tissue, the liver, can be used to evaluate relevant hypothesis and discover novel mechanisms of hormonal action. We have evaluated the differential effects of Growth Hormone (GH) and estrogen in the regulation of hepatic gender differentiated gene expression as well as the involvement of sterol regulatory element-binding proteins (SREBPs) in the hepatic actions of GH and thyroid hormone. Results Little similarity exists between liver transcript profiles regulated by 17-α-ethinylestradiol and those induced by the continuos infusion of bGH. On the other hand, strong correlations were found between both profiles and the female enriched transcript profile. Therefore, estrogens have feminizing effects in male rat liver which are different from those induced by GH. The similarity between bGH and T3 were limited to a small group of genes, most of which are involved in lipogenesis. An in silico promoter analysis of genes rapidly regulated by thyroid hormone predicted the activation of SREBPs by short-term treatment in vivo. It was further demonstrated that proteolytic processing of SREBP1 in the endoplasmic reticulum might contribute to the rapid actions of T3 on these genes. Conclusion This report illustrates how a meta-analysis of multiple transcript profiles can be used to link knowledge concerning endocrine physiology to hormonally induced changes in gene expression. We conclude that both GH and estrogen are important determinants of gender-related differences in hepatic gene expression. Rapid hepatic thyroid hormone effects affect genes involved in lipogenesis possibly through the induction of SREBP1 proteolytic processing.
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Affiliation(s)
- Nina Ståhlberg
- Department of Molecular Medicine, Karolinska Institute, 17176 Stockholm, Sweden
| | - Roxana Merino
- Department of Molecular Medicine, Karolinska Institute, 17176 Stockholm, Sweden
| | - Luis Henríquez Hernández
- Health Sciences Center, Pharmacology Section, Las Palmas de GC University – Instituto Canario de Investigación del Cancer – RTICCC, 35080 – Las Palmas de GC, Spain
| | - Leandro Fernández-Pérez
- Health Sciences Center, Pharmacology Section, Las Palmas de GC University – Instituto Canario de Investigación del Cancer – RTICCC, 35080 – Las Palmas de GC, Spain
| | - Albin Sandelin
- Center for Genomics and Bioinformatics, Karolinska Institute, 17176 Stockholm, Sweden
| | - Pär Engström
- Center for Genomics and Bioinformatics, Karolinska Institute, 17176 Stockholm, Sweden
| | - Petra Tollet-Egnell
- Department of Molecular Medicine, Karolinska Institute, 17176 Stockholm, Sweden
| | - Boris Lenhard
- Center for Genomics and Bioinformatics, Karolinska Institute, 17176 Stockholm, Sweden
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Toscano WA, Oehlke KP. Systems biology: new approaches to old environmental health problems. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2005; 2:4-9. [PMID: 16705795 PMCID: PMC3814690 DOI: 10.3390/ijerph2005010004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2004] [Accepted: 02/06/2005] [Indexed: 12/26/2022]
Abstract
The environment plays a pivotal role as a human health determinant and presence of hazardous pollutants in the environment is often implicated in human disease. That pollutants cause human diseases however is often controversial because data connecting exposure to environmental hazards and human diseases are not well defined, except for some cancers and syndromes such as asthma. Understanding the complex nature of human-environment interactions and the role they play in determining the state of human health is one of the more compelling problems in public health. We are becoming more aware that the reductionist approach promulgated by current methods has not, and will not yield answers to the broad questions of population health risk analysis. If substantive applications of environment-gene interactions are to be made, it is important to move to a systems level approach, to take advantage of epidemiology and molecular genomic advances. Systems biology is the integration of genomics, transcriptomics, proteomics, and metabolomics together with computer technology approaches to elucidate environmentally caused disease in humans. We discuss the applications of environmental systems biology as a route to solution of environmental health problems.
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Affiliation(s)
- William A Toscano
- Div. of Environmental Health Sciences, University of Minnesota School of Public Health, Minneapolis, MN 55455, USA.
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Brink CB, Harvey BH, Bodenstein J, Venter DP, Oliver DW. Recent advances in drug action and therapeutics: relevance of novel concepts in G-protein-coupled receptor and signal transduction pharmacology. Br J Clin Pharmacol 2004; 57:373-87. [PMID: 15025734 PMCID: PMC1884481 DOI: 10.1111/j.1365-2125.2003.02046.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2003] [Accepted: 11/03/2003] [Indexed: 12/23/2022] Open
Abstract
PROBLEM STATEMENT During especially the past two decades many discoveries in biological sciences, and in particular at the molecular and genetic level, have greatly impacted on our knowledge and understanding of drug action and have helped to develop new drugs and therapeutic strategies. Furthermore, many exciting new drugs acting via novel pharmacological mechanisms are expected to be in clinical use in the not too distant future. SCOPE AND CONTENTS OF REVIEW In this educational review, these concepts are explained and their relevance illustrated by examples of drugs used commonly in the clinical setting, with special reference to the pharmacology of G-protein-coupled receptors. The review also addresses the basic theoretical concepts of full and partial agonism, neutral antagonism, inverse agonism and protean and ligand-selective agonism, and the relevance of these concepts in current rational drug therapy. Moreover, the mechanisms whereby receptor signalling (and eventually response to drugs) is fine-tuned, such as receptor promiscuity, agonist-directed trafficking of receptor signalling, receptor trafficking, receptor 'cross-talk' and regulators of G-protein signalling (RGSs) are discussed, from theory to proposed therapeutic implications. CONCLUSIONS It is concluded that the understanding of molecular receptor and signal transduction pharmacology enables clinicians to improve their effective implementation of current and future pharmacotherapy, ultimately enhancing the quality of life of their patients.
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Affiliation(s)
- C B Brink
- Division of Pharmacology, School of Pharmacy, Potchefstroom University for CHE, Potchefstroom, South Africa.
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Abstract
Jaundice, which is caused by accumulation of bilirubin, is extremely common in newborn infants. Phototherapy is an effective treatment, but a drug therapy would also be desirable. A Chinese herbal remedy for jaundice called Yin Zhi Huang is now shown to activate a liver receptor that enhances the clearance of bilirubin (see the related article beginning on page 137). This discovery could lead to improved pharmaceutical treatments for neonatal jaundice.
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Affiliation(s)
- Mitchell A Lazar
- Departments of Medicine and Genetics, and the Penn Diabetes Center, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6149, USA.
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17
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Abstract
Jaundice, which is caused by accumulation of bilirubin, is extremely common in newborn infants. Phototherapy is an effective treatment, but a drug therapy would also be desirable. A Chinese herbal remedy for jaundice called Yin Zhi Huang is now shown to activate a liver receptor that enhances the clearance of bilirubin (see the related article beginning on page 137). This discovery could lead to improved pharmaceutical treatments for neonatal jaundice.
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Affiliation(s)
- Mitchell A Lazar
- Departments of Medicine and Genetics, and the Penn Diabetes Center, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6149, USA.
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Maglich JM, Caravella JA, Lambert MH, Willson TM, Moore JT, Ramamurthy L. The first completed genome sequence from a teleost fish (Fugu rubripes) adds significant diversity to the nuclear receptor superfamily. Nucleic Acids Res 2003; 31:4051-8. [PMID: 12853622 PMCID: PMC165959 DOI: 10.1093/nar/gkg444] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Defining complete sets of gene family members from diverse species provides the foundation for comparative studies. Using a bioinformatic approach, we have defined the entire nuclear receptor complement within the first available complete sequence of a non-human vertebrate (the teleost fish Fugu rubripes). In contrast to the human set (48 total nuclear receptors), we found 68 nuclear receptors in the Fugu genome. All 68 Fugu receptors had a clear human homolog, thus defining no new nuclear receptor subgroups. A reciprocal analysis showed that each human receptor had one or more Fugu orthologs, excepting CAR (NR1I3) and LXRbeta (NR1H2). These 68 receptors add striking diversity to the known nuclear receptor superfamily and provide important comparators to human nuclear receptors. We have compared several pharmacologically relevant human nuclear receptors (FXR, LXRalpha/beta, CAR, PXR, VDR and PPARalpha/gamma/delta) to their Fugu orthologs. This comparison included expression analysis across five Fugu tissue types. All of the Fugu receptors that were analyzed by PCR in this study were expressed, indicating that the majority of the additional Fugu receptors are likely to be functional.
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Affiliation(s)
- Jodi M Maglich
- Nuclear Receptor Discovery Research, Research Triangle Park, NC 27709, USA
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