1
|
Lim JPL, Braza MKE, Nellas RB. The effect of ligand affinity to the contact dynamics of the ligand binding domain of thyroid hormone receptor - retinoid X receptor. J Mol Graph Model 2021; 104:107829. [PMID: 33450664 DOI: 10.1016/j.jmgm.2020.107829] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 12/19/2020] [Accepted: 12/21/2020] [Indexed: 11/19/2022]
Abstract
Ligand-based allostery has been gaining attention for its importance in protein regulation and implication in drug design. One of the interesting cases of protein allostery is the thyroid hormone receptor - retinoid x receptor (TR:RXR), which regulates the gene expression of important physiological processes, such as development and metabolism. It is regulated by the TR native ligand triiodothyronine (T3), which displays anticooperative behavior to the RXR ligand 9-cis retinoic acid (9C). In contrast to this anticooperative behavior, 9C has been shown to increase the activity of TR:RXR. Here we probed the influence of the affinity and the interactions of the TR ligand to the allostery of the TR:RXR through contact dynamics and residue networks. The TR ligand analogs were designed to have higher (G2) and lower (N1) binding energies than T3 when docked to the TR:RXR(9C) complex. The aqueous TR(N1/T3/G2):RXR(9C) complexes were subjected to 30 ns all-atom simulations using theNAMD. The program CAMERRA was used to capture the subtle perturbations of TR:RXR by mapping the residue contact dynamics. Various parts of the TR ligands; including the hydrophilic head, the iodine substituents, and the ligand tail; have been probed for their significance in ligand affinity. The results on the T3 and G2 complexes suggest that ligand affinity can be utilized as a predictor for anticooperative systems on which ligand is more likely to dissociate or remain bound. All 3 complexes also display distinct contact networks for cross-dimer signalling and ligand communication. Understanding ligand-based allostery could potentially unveil secrets of ligand-regulated protein dynamics, a foundation for the design of better and more efficient allosteric drugs.
Collapse
Affiliation(s)
- James Peter L Lim
- Institute of Chemistry, College of Science, University of the Philippines Diliman, Quezon City, Philippines
| | - Mac Kevin E Braza
- Institute of Chemistry, College of Science, University of the Philippines Diliman, Quezon City, Philippines
| | - Ricky B Nellas
- Institute of Chemistry, College of Science, University of the Philippines Diliman, Quezon City, Philippines.
| |
Collapse
|
2
|
Tang S, Sun L, Wang F. Identification of highly active natural thyroid hormone receptor agonists by pharmacophore-based virtual screening. J Biomol Struct Dyn 2020; 39:901-910. [PMID: 31997713 DOI: 10.1080/07391102.2020.1719890] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Thyroid hormone receptor (TR) is an important target for the treatment of metabolic diseases. The X-ray crystallographic data for the TR complexed with different ligands were employed to generate feature-based pharmacophore models of the active site of TR receptor. The derived hypothesis was then used to find novel hit compounds through an in silico virtual screening on the Universal Natural Products Database (UNPD). The binding mode and action mechanism of the hit compounds were further investigated by molecular docking and molecular dynamics studies, then compounds possessing similar binding site with the crystal ligand were subjected to binding activity assay. Finally, UNPD19665 and UNPD184785 were proved to be more active than crystal TR ligands, with a binding activity value of 9.82 nM and 12.62 nM, respectively. Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Shenjiao Tang
- School of Life Science, Linyi University, Linyi, China
| | - Lin Sun
- School of Life Science, Linyi University, Linyi, China
| | - Fangfang Wang
- School of Life Science, Linyi University, Linyi, China
| |
Collapse
|
3
|
Design, synthesis and biological evaluation of novel TRβ selective agonists sustained by ADME-toxicity analysis. Eur J Med Chem 2019; 188:112006. [PMID: 31931337 DOI: 10.1016/j.ejmech.2019.112006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 12/11/2019] [Accepted: 12/20/2019] [Indexed: 12/17/2022]
Abstract
Although triiodothyronine (T3) induces several beneficial effects on lipid metabolism, its use is hampered by toxic side-effects, such as tachycardia, arrhythmia, heart failure, bone and muscle catabolism and mood disturbances. Since the α isoform of thyroid hormone receptors (TRs) is the main cause of T3-related harmful effects, several efforts have been made to develop selective agonists of the β isoform that could induce some beneficial effects (i.e. lowering triglyceride and cholesterol levels reducing obesity and improving metabolic syndrome), while overcoming most of the adverse T3-dependent side effects. Herein, we describe the drug discovery process sustained by ADME-Toxicity analysis that led us to identify novel agonists with selectivity for the isoform TRβ and an acceptable off-target and absorption, distribution metabolism, excretion and toxicity (ADME-Tox) profile. Within the small series of compounds synthesized, derivatives 1 and 3, emerge from this analysis as "potentially safe" to be engaged in preclinical studies. In in vitro investigation proved that both compounds were able to reduce lipid accumulation in HepG2 and promote lipolysis with comparable effects to those elicited by T3, used as reference drug. Moreover, a preliminary in vivo study confirmed the apparent lack of toxicity, thus suggesting compounds 1 and 3 as new potential TRβ-selective thyromimetics.
Collapse
|
4
|
Devereaux J, Ferrara SJ, Scanlan TS. Quantification of Thyromimetic Sobetirome Concentration in Biological Tissue Samples. Methods Mol Biol 2018; 1801:193-206. [PMID: 29892826 DOI: 10.1007/978-1-4939-7902-8_16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Thyroid hormone is a principal regulator of essential processes in vertebrate physiology and homeostasis. Synthetic derivatives of thyroid hormone, known as thyromimetics, display desirable therapeutic properties. Thoroughly understanding how thyromimetics distribute throughout the body is crucial for their development and this requires appropriate bioanalytical techniques to quantify drug levels in different tissues. Here, we describe a detailed protocol for the quantification of the thyromimetic sobetirome using liquid chromatography tandem-mass spectrometry (LC-MS/MS).
Collapse
Affiliation(s)
- Jordan Devereaux
- Program in Chemical Biology, Department of Physiology & Pharmacology, Oregon Health & Science University, Portland, OR, USA
| | - Skylar J Ferrara
- Program in Chemical Biology, Department of Physiology & Pharmacology, Oregon Health & Science University, Portland, OR, USA
| | - Thomas S Scanlan
- Program in Chemical Biology, Department of Physiology & Pharmacology, Oregon Health & Science University, Portland, OR, USA.
| |
Collapse
|
5
|
Devereaux J, Ferrara SJ, Banerji T, Placzek AT, Scanlan TS. Increasing Thyromimetic Potency through Halogen Substitution. ChemMedChem 2016; 11:2459-2465. [PMID: 27731931 PMCID: PMC5389920 DOI: 10.1002/cmdc.201600408] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Indexed: 12/17/2022]
Abstract
Sobetirome is one of the most studied thyroid hormone receptor β (TRβ)-selective thyromimetics in the field due to its excellent selectivity and potency. A small structural change-replacing the 3,5-dimethyl groups of sobetirome with either chlorine or bromine-produces significantly more potent compounds, both in vitro and in vivo. These halogenated compounds induce transactivation of a TRβ-mediated cell-based reporter with an EC50 value comparable to that of T3, access the central nervous system (CNS) at levels similar to their parent, and activate an endogenous TR-regulated gene in the brain with an EC50 value roughly five-fold lower than that of sobetirome. Previous studies suggest that this apparent increase in affinity can be explained by halogen bonding between the ligand and a backbone carbonyl group in the receptor. This makes the new analogues potential candidates for treating CNS disorders that may respond favorably to thyroid-hormone-stimulated pathways.
Collapse
Affiliation(s)
- Jordan Devereaux
- Department of Physiology & Pharmacology, Program in Chemical Biology, Oregon Health & Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| | - Skylar J Ferrara
- Department of Physiology & Pharmacology, Program in Chemical Biology, Oregon Health & Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| | - Tania Banerji
- Department of Physiology & Pharmacology, Program in Chemical Biology, Oregon Health & Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| | - Andrew T Placzek
- Department of Physiology & Pharmacology, Program in Chemical Biology, Oregon Health & Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| | - Thomas S Scanlan
- Department of Physiology & Pharmacology, Program in Chemical Biology, Oregon Health & Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| |
Collapse
|
6
|
Milanesi A, Lee JW, Kim NH, Liu YY, Yang A, Sedrakyan S, Kahng A, Cervantes V, Tripuraneni N, Cheng SY, Perin L, Brent GA. Thyroid Hormone Receptor α Plays an Essential Role in Male Skeletal Muscle Myoblast Proliferation, Differentiation, and Response to Injury. Endocrinology 2016; 157:4-15. [PMID: 26451739 PMCID: PMC4701883 DOI: 10.1210/en.2015-1443] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Thyroid hormone plays an essential role in myogenesis, the process required for skeletal muscle development and repair, although the mechanisms have not been established. Skeletal muscle develops from the fusion of precursor myoblasts into myofibers. We have used the C2C12 skeletal muscle myoblast cell line, primary myoblasts, and mouse models of resistance to thyroid hormone (RTH) α and β, to determine the role of thyroid hormone in the regulation of myoblast differentiation. T3, which activates thyroid hormone receptor (TR) α and β, increased myoblast differentiation whereas GC1, a selective TRβ agonist, was minimally effective. Genetic approaches confirmed that TRα plays an important role in normal myoblast proliferation and differentiation and acts through the Wnt/β-catenin signaling pathway. Myoblasts with TRα knockdown, or derived from RTH-TRα PV (a frame-shift mutation) mice, displayed reduced proliferation and myogenic differentiation. Moreover, skeletal muscle from the TRα1PV mutant mouse had impaired in vivo regeneration after injury. RTH-TRβ PV mutant mouse model skeletal muscle and derived primary myoblasts did not have altered proliferation, myogenic differentiation, or response to injury when compared with control. In conclusion, TRα plays an essential role in myoblast homeostasis and provides a potential therapeutic target to enhance skeletal muscle regeneration.
Collapse
Affiliation(s)
- Anna Milanesi
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Jang-Won Lee
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Nam-Ho Kim
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Yan-Yun Liu
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - An Yang
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Sargis Sedrakyan
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Andrew Kahng
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Vanessa Cervantes
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Nikita Tripuraneni
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Sheue-yann Cheng
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Laura Perin
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Gregory A Brent
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| |
Collapse
|
7
|
Devillers J, Bro E, Millot F. Prediction of the endocrine disruption profile of pesticides. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2015; 26:831-852. [PMID: 26548639 DOI: 10.1080/1062936x.2015.1104809] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Numerous manmade chemicals released into the environment can interfere with normal, hormonally regulated biological processes to adversely affect the development and reproductive functions of living species. Various in vivo and in vitro tests have been designed for detecting endocrine disruptors, but the number of chemicals to test is so high that to save time and money, (quantitative) structure-activity relationship ((Q)SAR) models are increasingly used as a surrogate for these laboratory assays. However, most of them focus only on a specific target (e.g. estrogenic or androgenic receptor) while, to be more efficient, endocrine disruption modelling should preferentially consider profiles of activities to better gauge this complex phenomenon. In this context, an attempt was made to evaluate the endocrine disruption profile of 220 structurally diverse pesticides using the Endocrine Disruptome simulation (EDS) tool, which simultaneously predicts the probability of binding of chemicals on 12 nuclear receptors. In a first step, the EDS web-based system was successfully applied to 16 pharmaceutical compounds known to target at least one of the studied receptors. About 13% of the studied pesticides were estimated to be potential disruptors of the endocrine system due to their high predicted affinity for at least one receptor. In contrast, about 55% of them were unlikely to be endocrine disruptors. The simulation results are discussed and some comments on the use of the EDS tool are made.
Collapse
Affiliation(s)
| | - E Bro
- b Research Department , National Game and Wildlife Institute (ONCFS) , Le Perray en Yvelines , France
| | - F Millot
- b Research Department , National Game and Wildlife Institute (ONCFS) , Le Perray en Yvelines , France
| |
Collapse
|
8
|
Kelly MJ, Pietranico-Cole S, Larigan JD, Haynes NE, Reynolds CH, Scott N, Vermeulen J, Dvorozniak M, Conde-Knape K, Huang KS, So SS, Thakkar K, Qian Y, Banner B, Mennona F, Danzi S, Klein I, Taub R, Tilley J. Discovery of 2-[3,5-dichloro-4-(5-isopropyl-6-oxo-1,6-dihydropyridazin-3-yloxy)phenyl]-3,5-dioxo-2,3,4,5-tetrahydro[1,2,4]triazine-6-carbonitrile (MGL-3196), a Highly Selective Thyroid Hormone Receptor β agonist in clinical trials for the treatment of dyslipidemia. J Med Chem 2014; 57:3912-23. [PMID: 24712661 DOI: 10.1021/jm4019299] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The beneficial effects of thyroid hormone (TH) on lipid levels are primarily due to its action at the thyroid hormone receptor β (THR-β) in the liver, while adverse effects, including cardiac effects, are mediated by thyroid hormone receptor α (THR-α). A pyridazinone series has been identified that is significantly more THR-β selective than earlier analogues. Optimization of this series by the addition of a cyanoazauracil substituent improved both the potency and selectivity and led to MGL-3196 (53), which is 28-fold selective for THR-β over THR-α in a functional assay. Compound 53 showed outstanding safety in a rat heart model and was efficacious in a preclinical model at doses that showed no impact on the central thyroid axis. In reported studies in healthy volunteers, 53 exhibited an excellent safety profile and decreased LDL cholesterol (LDL-C) and triglycerides (TG) at once daily oral doses of 50 mg or higher given for 2 weeks.
Collapse
Affiliation(s)
- Martha J Kelly
- Madrigal Pharmaceuticals, Inc. , Fort Washington, Pennsylvania 19034, United States
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Takahashi N, Maeda K, Asano Y, Watanabe N. Synthesis and pharmacological characterization of 1-benzyl-4-aminoindole-based thyroid hormone receptor β agonists. Bioorg Med Chem 2014; 22:488-98. [DOI: 10.1016/j.bmc.2013.11.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 10/31/2013] [Accepted: 11/01/2013] [Indexed: 12/18/2022]
|
10
|
Fujihara T, Nishida T, Terao J, Tsuji Y. Synthesis and characterization of ruthenium(II) complexes with dendritic N-heterocyclic carbene ligands. Inorganica Chim Acta 2014. [DOI: 10.1016/j.ica.2013.05.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
11
|
Abstract
Thyroid hormones (THs) are important in the development and maintenance of lipid and energy homeostasis. THs act through two closely related TH receptors (TRs α and β), which are conditional transcription factors. Recently, TH analogues or thyromimetics with varying degrees of TR subtype and liver uptake selectivity have been developed. These compounds exert beneficial effects of TH excess states without many undesirable TR-dependent side effects. Several selective TR modulators (STRMs) showed exceptionally promising results in lowering serum cholesterol in preclinical animal models and human clinical studies. Moreover, some first generation STRMs elicit other potentially beneficial effects on obesity, glucose metabolism, and nonalcoholic fatty liver disease (NAFLD). While it was initially thought that STRMs would be an effective long-term therapy to combat elevated cholesterol, possibly in conjunction with another cholesterol-lowering therapy, the statins, three major first generation STRMs failed to progress beyond early phase III human trials. The aim of this review is to discuss how STRMs work, their actions in preclinical animal models and human clinical trials, why they did not progress beyond clinical trials as cholesterol-lowering therapeutics, whether selective TR modulation continues to hold promise for dyslipidemias, and whether members of this drug class could be applied to the treatment of other aspects of metabolic syndrome and human genetic disease.
Collapse
Affiliation(s)
- Sunitha Meruvu
- Center for Genomic Medicine, Houston Methodist Research Institute , Houston, Texas
| | | | | | | |
Collapse
|
12
|
Burris TP, Solt LA, Wang Y, Crumbley C, Banerjee S, Griffett K, Lundasen T, Hughes T, Kojetin DJ. Nuclear receptors and their selective pharmacologic modulators. Pharmacol Rev 2013; 65:710-78. [PMID: 23457206 PMCID: PMC11060414 DOI: 10.1124/pr.112.006833] [Citation(s) in RCA: 185] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Nuclear receptors are ligand-activated transcription factors and include the receptors for steroid hormones, lipophilic vitamins, sterols, and bile acids. These receptors serve as targets for development of myriad drugs that target a range of disorders. Classically defined ligands that bind to the ligand-binding domain of nuclear receptors, whether they are endogenous or synthetic, either activate receptor activity (agonists) or block activation (antagonists) and due to the ability to alter activity of the receptors are often termed receptor "modulators." The complex pharmacology of nuclear receptors has provided a class of ligands distinct from these simple modulators where ligands display agonist/partial agonist/antagonist function in a tissue or gene selective manner. This class of ligands is defined as selective modulators. Here, we review the development and pharmacology of a range of selective nuclear receptor modulators.
Collapse
Affiliation(s)
- Thomas P Burris
- The Scripps Research Institute, 130 Scripps Way 2A1, Jupiter, FL 33458, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Miller DK. Facile conversion of chromane-6-triflate to chromane-6-alanines under palladium conditions. Tetrahedron Lett 2013; 54:811-813. [DOI: 10.1016/j.tetlet.2012.11.115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
14
|
Abstract
Selective thyromimetics are synthetic analogs of thyroid hormones with tissue-specific thyroid hormone actions. Tissue selectivity is partly mediated by selectivity for the thyroid hormone receptor-β isoform, but is also enhanced by tissue-selective uptake. Several preclinical animal models and recent human clinical trials have provided sound evidence that thyromimetics can serve as pharmacological tools to improve serum lipids without affecting heart rate. Thyromimetics consistently and efficiently lowered low-density lipoprotein cholesterol and lipoprotein (a) plasma levels without positive chronotropic effects. Most importantly, thyromimetics had a synergistic action when used in addition to 3-hydroxy-3-methylglutaryl CoA reductase inhibitors. Animal data have further suggested that thyromimetics might be useful in the treatment of obesity, hepatic steatosis and atherosclerosis. However, only long-term phase III clinical trials will tell if the observed lipid lowering effects of thyromimetics will improve cardiovascular outcome in humans, too. At the moment, the treatment of dyslipidemia seems to be the major indication for the therapeutic use of thyromimetics, which are now rapidly moving from bench to bed-side.
Collapse
Affiliation(s)
- Ivan Tancevski
- Department of Internal Medicine I, Innsbruck Medical University, Innsbruck, Austria.
| | | | | |
Collapse
|
15
|
de Araujo AS, Martínez L, de Paula Nicoluci R, Skaf MS, Polikarpov I. Structural modeling of high-affinity thyroid receptor-ligand complexes. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2010; 39:1523-36. [PMID: 20512645 DOI: 10.1007/s00249-010-0610-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Revised: 04/27/2010] [Accepted: 05/04/2010] [Indexed: 11/24/2022]
Abstract
Understanding the molecular basis of the binding modes of natural and synthetic ligands to nuclear receptors is fundamental to our comprehension of the activation mechanism of this important class of hormone regulated transcription factors and to the development of new ligands. Thyroid hormone receptors (TR) are particularly important targets for pharmaceuticals development because TRs are associated with the regulation of metabolic rates, body weight, and circulating levels of cholesterol and triglycerides in humans. While several high-affinity ligands are known, structural information is only partially available. In this work we obtain structural models of several TR-ligand complexes with unknown structure by docking high affinity ligands to the receptors' ligand binding domain with subsequent relaxation by molecular dynamics simulations. The binding modes of these ligands are discussed providing novel insights into the development of TR ligands. The experimental binding free energies are reasonably well-reproduced from the proposed models using a simple linear interaction energy free-energy calculation scheme.
Collapse
Affiliation(s)
- Alexandre Suman de Araujo
- Instituto de Física de São Carlos, Universidade de São Paulo, Av Trabalhador SaoCarlense 400, IFSC, Grupo de Cristalografia, PO Box 369, Sao Carlos, SP 13560-970, Brazil
| | | | | | | | | |
Collapse
|
16
|
Boyer SH, Jiang H, Jacintho JD, Reddy MV, Li H, Li W, Godwin JL, Schulz WG, Cable EE, Hou J, Wu R, Fujitaki JM, Hecker SJ, Erion MD. Synthesis and biological evaluation of a series of liver-selective phosphonic acid thyroid hormone receptor agonists and their prodrugs. J Med Chem 2009; 51:7075-93. [PMID: 18975928 DOI: 10.1021/jm800824d] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Phosphonic acid (PA) thyroid hormone receptor (TR) agonists were synthesized to exploit the poor distribution of PA-based drugs to extrahepatic tissues and thereby to improve the therapeutic index. Nine PAs showed excellent TR binding affinities (TRbeta(1), K(i) < 10 nM), and most of them demonstrated significant cholesterol lowering effects in a cholesterol-fed rat (CFR) model. Unlike the corresponding carboxylic acid analogue and T(3), PA 22c demonstrated liver-selective effects by inducing maximal mitochondrial glycerol-3-phosphate dehydrogenase activity in rat liver while having no effect in the heart. Because of the low oral bioavailability of PA 22c, a series of prodrugs was synthesized and screened for oral efficacy in the CFR assay. The liver-activated cyclic 1-(3-chlorophenyl)-1,3-propanyl prodrug (MB07811) showed potent lipid lowering activity in the CFR (ED(50) 0.4 mg/kg, po) and good oral bioavailability (40%, rat) and was selected for development for the treatment of hypercholesterolemia.
Collapse
Affiliation(s)
- Serge H Boyer
- Departments of Medicinal Chemistry and Biosciences, Metabasis Therapeutics, Inc., 11119 North Torrey Pines Road, La Jolla, California 92037, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Kolkhof P, Bärfacker L, Hillisch A, Haning H, Schäfer S. Nuclear Receptors as Targets in Cardiovascular Diseases. ACTA ACUST UNITED AC 2008. [DOI: 10.1002/9783527623297.ch13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
18
|
Scanlan TS. Sobetirome: a case history of bench-to-clinic drug discovery and development. Heart Fail Rev 2008; 15:177-82. [DOI: 10.1007/s10741-008-9122-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2008] [Accepted: 10/21/2008] [Indexed: 10/21/2022]
|
19
|
Bleicher L, Aparicio R, Nunes FM, Martinez L, Gomes Dias SM, Figueira ACM, Santos MAM, Venturelli WH, da Silva R, Donate PM, Neves FA, Simeoni LA, Baxter JD, Webb P, Skaf MS, Polikarpov I. Structural basis of GC-1 selectivity for thyroid hormone receptor isoforms. BMC STRUCTURAL BIOLOGY 2008; 8:8. [PMID: 18237438 PMCID: PMC2275733 DOI: 10.1186/1472-6807-8-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2007] [Accepted: 01/31/2008] [Indexed: 12/14/2022]
Abstract
Background Thyroid receptors, TRα and TRβ, are involved in important physiological functions such as metabolism, cholesterol level and heart activities. Whereas metabolism increase and cholesterol level lowering could be achieved by TRβ isoform activation, TRα activation affects heart rates. Therefore, β-selective thyromimetics have been developed as promising drug-candidates for treatment of obesity and elevated cholesterol level. GC-1 [3,5-dimethyl-4-(4'-hydroxy-3'-isopropylbenzyl)-phenoxy acetic acid] has ability to lower LDL cholesterol with 600- to 1400-fold more potency and approximately two- to threefold more efficacy than atorvastatin (Lipitor©) in studies in rats, mice and monkeys. Results To investigate GC-1 specificity, we solved crystal structures and performed molecular dynamics simulations of both isoforms complexed with GC-1. Crystal structures reveal that, in TRα Arg228 is observed in multiple conformations, an effect triggered by the differences in the interactions between GC-1 and Ser277 or the corresponding asparagine (Asn331) of TRβ. The corresponding Arg282 of TRβ is observed in only one single stable conformation, interacting effectively with the ligand. Molecular dynamics support this model: our simulations show that the multiple conformations can be observed for the Arg228 in TRα, in which the ligand interacts either strongly with the ligand or with the Ser277 residue. In contrast, a single stable Arg282 conformation is observed for TRβ, in which it strongly interacts with both GC-1 and the Asn331. Conclusion Our analysis suggests that the key factors for GC-1 selectivity are the presence of an oxyacetic acid ester oxygen and the absence of the amino group relative to T3. These results shed light into the β-selectivity of GC-1 and may assist the development of new compounds with potential as drug candidates to the treatment of hypercholesterolemia and obesity.
Collapse
Affiliation(s)
- Lucas Bleicher
- Instituto de Física de São Carlos, Universidade de São Paulo, Avenida Trabalhador São Carlense, 400 CEP 13560-970 São Carlos, SP, Brazil.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Valadares NF, Castilho MS, Polikarpov I, Garratt RC. 2D QSAR studies on thyroid hormone receptor ligands. Bioorg Med Chem 2007; 15:4609-17. [PMID: 17467994 DOI: 10.1016/j.bmc.2007.04.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2007] [Revised: 03/27/2007] [Accepted: 04/04/2007] [Indexed: 12/25/2022]
Abstract
2D QSAR studies were carried out for a series of 55 ligands for the Thyroid receptors, TRalpha and TRbeta. Significant cross-validated correlation coefficients (q(2)=0.781 (TRalpha) and 0.693 (TRbeta)) were obtained. The models' predictive abilities were proved more valuable than the classical 2D-QSAR, and were further investigated by means of an external test set of 13 compounds. The predicted values are in good agreement with experimental values, suggesting that the models could be useful in the design of novel, more potent TR ligands. Contribution map analysis identified a number of positions that are promising for the development of receptor isoform specific ligands.
Collapse
Affiliation(s)
- Napoleão F Valadares
- Departamento de Física e Informática, Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador São-carlense 400, 13560-970 São Carlos-SP, Brazil.
| | | | | | | |
Collapse
|
21
|
Haning H, Mueller U, Schmidt G, Schmeck C, Voehringer V, Kretschmer A, Bischoff H. Novel heterocyclic thyromimetics. Part 2. Bioorg Med Chem Lett 2007; 17:3992-6. [PMID: 17499989 DOI: 10.1016/j.bmcl.2007.04.085] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2007] [Revised: 04/25/2007] [Accepted: 04/25/2007] [Indexed: 11/16/2022]
Abstract
Novel heterocyclic thyromimetics are presented carrying carboxy-substituted benzofurans or sulfur containing heterocycles, as replacements for the amino acid side chain of T3. Potent agonists were identified in both series. SAR trends are examined and found to be mostly consistent with previously published thyromimetics. The lack of isoform selectivity demonstrated with isoform-selective transient THR transfection assays has been confirmed by corresponding in vivo studies.
Collapse
Affiliation(s)
- Helmut Haning
- Bayer HealthCare AG, Bayer Schering Pharma Global Drug Discovery, D-42096 Wuppertal, Germany.
| | | | | | | | | | | | | |
Collapse
|
22
|
Komatsu T, Hirano T, Songkram C, Kawachi E, Kagechika H. Novel thyroid hormone receptor antagonists with an N-alkylated diphenylamine skeleton. Bioorg Med Chem 2007; 15:3115-26. [PMID: 17363258 DOI: 10.1016/j.bmc.2007.02.053] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2007] [Revised: 02/24/2007] [Accepted: 02/27/2007] [Indexed: 11/24/2022]
Abstract
Thyroid hormones play important roles in growth, development and homeostasis, and disruption of their functions induces serious disease, so novel synthetic thyroid hormone analogues are candidates for clinical application. We designed and synthesized novel diphenylamine derivatives with a thiazolidinedione moiety as the terminal polar group as thyroid hormone receptor (TR) antagonists. Compounds bearing an appropriately sized N-alkyl group showed antagonistic activities towards both the hTRalpha1 and hTRbeta1 subtypes.
Collapse
Affiliation(s)
- Takuma Komatsu
- School of Biomedical Science, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan
| | | | | | | | | |
Collapse
|
23
|
|
24
|
Hashimoto A, Shi Y, Drake K, Koh JT. Design and synthesis of complementing ligands for mutant thyroid hormone receptor TRβ(R320H): a tailor-made approach toward the treatment of resistance to thyroid hormone. Bioorg Med Chem 2005; 13:3627-39. [PMID: 15862991 DOI: 10.1016/j.bmc.2005.03.040] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2005] [Revised: 03/17/2005] [Accepted: 03/21/2005] [Indexed: 11/18/2022]
Abstract
The thyroid hormone receptors (TR) are ligand-dependant transcription factors that regulate key genes involved in metabolic regulation, thermogenesis and development. Resistance to thyroid hormone (RTH) is a genetic disease associated with mutations to TRbeta that lack or show reduced responsiveness to thyroid hormone (triiodothyronine). Previously we reported that the neutral alcohol-based thyromimetic HY-1 can selectively restore activity to a functionally impaired form of TR associated with RTH without over-stimulating TRalpha, which has been associated with undesirable side effects. Two new series of tetrazole and thiazolidinedione based ligands were evaluated for their ability to recover potency and efficacy to three of the most common RTH-associated mutants, TRbeta(R320C), TRbeta(R320H), and TRbeta(R316H), in cell based assays. A new thiazolidinedione based ligand AH-9 was identified, which has near wild-type potency (EC(50)=0.54 nM) to TRbeta(R320C) and TRbeta(R320H). Significantly, AH-9 is equipotent toward TRalpha(wt), TRbeta(wt), TRbeta(R320C), and TRbeta(R320H), suggesting that AH-9 may have the potential to restore the normal homeostatic balance of thyroid hormone actions in patients or models harboring these mutations.
Collapse
Affiliation(s)
- Atsushi Hashimoto
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
| | | | | | | |
Collapse
|
25
|
Haning H, Woltering M, Mueller U, Schmidt G, Schmeck C, Voehringer V, Kretschmer A, Pernerstorfer J. Novel heterocyclic thyromimetics. Bioorg Med Chem Lett 2005; 15:1835-40. [PMID: 15780617 DOI: 10.1016/j.bmcl.2005.02.028] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2004] [Revised: 02/07/2005] [Accepted: 02/08/2005] [Indexed: 11/29/2022]
Abstract
Novel heterocycle-fused thyromimetics are presented carrying indoles or indazoles instead of the phenolic group in T3. Potent agonists were identified in both series. SAR trends are examined and found to be mostly consistent with previously published thyromimetics. Moderate THRbeta selectivity (approx. 10-fold) was observed in the indole series using isoform-selective transient THR transfection assays.
Collapse
Affiliation(s)
- Helmut Haning
- BAYER HealthCare AG, Business Group Pharma, D-42096 Wuppertal, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Nguyen NH, Apriletti JW, Baxter JD, Scanlan TS. Hammett Analysis of Selective Thyroid Hormone Receptor Modulators Reveals Structural and Electronic Requirements for Hormone Antagonists. J Am Chem Soc 2005; 127:4599-608. [PMID: 15796525 DOI: 10.1021/ja0440093] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Selective thyroid hormone modulators that function as isoform-selective agonists or antagonists of the thyroid hormone receptors (TRs) might be therapeutically useful in diseases associated with aberrant hormone signaling. The most potent thyroid hormone antagonist reported to date is NH-3. To explore the significance of the 5'-p-nitroaryl moiety of NH-3 and understand what chemical features are important to confer antagonism, we sought to expand the structure-activity relationship data for the class of 5'-phenylethynyl GC-1 derivatives. Herein, we describe an improved synthetic route utilizing palladium-catalyzed chemistry for efficient access to a series of 5'-phenylethynyl compounds with varying size and electronic properties. We prepared and tested sixteen analogues for TR binding and transactivation activity. Substitution at the 5'-position decreased binding affinity, but retained TRbeta-selectivity. In transactivation assays, the analogues displayed a spectrum of agonist, antagonist, and mixed agonist/antagonist activity that correlated with electronic character in a Hammett analysis between sigma substituent value and TR modulation. Analogues NH-5, NH-7, NH-9, NH-11, and NH-23 displayed full antagonist activity with reduced potency compared to NH-3, indicating the nitro group is not required for antagonism. However, para-substitution with strong electron withdrawing properties on the 5'-aryl extension is important for antagonist activity, and antagonist potency-but not ligand receptor binding-was found to correlate linearly with the sigma values for the electron withdrawing substituents.
Collapse
Affiliation(s)
- Ngoc-Ha Nguyen
- Program in Chemistry and Chemical Biology, Department of Pharmaceutical Chemistry, University of California-San Francisco, San Francisco, CA 94143-0446, USA
| | | | | | | |
Collapse
|
27
|
Abstract
An excess of thyroid hormone (TH) leads to a mix of deleterious (increased heart rate, muscle wasting and osteoporosis) and beneficial effects (reduced serum cholesterol and lipoprotein A and weight loss). All of these actions are mediated by nuclear thyroid hormone receptors (TRs), however, genetic evidence suggests that different TR isoforms do not contribute equally to individual TH effects. Thus, TR isoform selective activators could mimic the beneficial aspects of TH excess while avoiding the harmful effects. This article reviews new selective TR activators, their mechanism of action (they work by targeting the TR-beta isoform) and their actions in animal models. It is clear that these compounds represent a promising new avenue for the treatment of lipid disorders and obesity.
Collapse
Affiliation(s)
- Paul Webb
- Diabetes Center and School of Medicine, University of California-San Francisco, San Francisco, CA 94143-0540, USA.
| |
Collapse
|
28
|
Moore JMR, Galicia SJ, McReynolds AC, Nguyen NH, Scanlan TS, Guy RK. Quantitative Proteomics of the Thyroid Hormone Receptor-Coregulator Interactions. J Biol Chem 2004; 279:27584-90. [PMID: 15100213 DOI: 10.1074/jbc.m403453200] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The thyroid hormone receptor regulates a diverse set of genes that control processes from embryonic development to adult homeostasis. Upon binding of thyroid hormone, the thyroid receptor releases corepressor proteins and undergoes a conformational change that allows for the interaction of coactivating proteins necessary for gene transcription. This interaction is mediated by a conserved motif, termed the NR box, found in many coregulators. Recent work has demonstrated that differentially assembled coregulator complexes can elicit specific biological responses. However, the mechanism for the selective assembly of these coregulator complexes has yet to be elucidated. To further understand the principles underlying thyroid receptor-coregulator selectivity, we designed a high-throughput in vitro binding assay to measure the equilibrium affinity of thyroid receptor to a library of potential coregulators in the presence of different ligands including the endogenous thyroid hormone T3, synthetic thyroid receptor beta-selective agonist GC-1, and antagonist NH-3. Using this homogenous method several coregulator NR boxes capable of associating with thyroid receptor at physiologically relevant concentrations were identified including ones found in traditional coactivating proteins such as SRC1, SRC2, TRAP220, TRBP, p300, and ARA70; and those in coregulators known to repress gene activation including RIP140 and DAX-1. In addition, it was discovered that the thyroid receptor-coregulator binding patterns vary with ligand and that this differential binding can be used to predict biological responses. Finally, it is demonstrated that this is a general method that can be applied to other nuclear receptors and can be used to establish rules for nuclear receptor-coregulator selectivity.
Collapse
Affiliation(s)
- Jamie M R Moore
- Department of Pharmaceutical Chemistry, University of California at San Francisco, San Francisco, California 94143-2280, USA
| | | | | | | | | | | |
Collapse
|
29
|
Baxter JD, Webb P, Grover G, Scanlan TS. Selective activation of thyroid hormone signaling pathways by GC-1: a new approach to controlling cholesterol and body weight. Trends Endocrinol Metab 2004; 15:154-7. [PMID: 15109613 DOI: 10.1016/j.tem.2004.03.008] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The current report describes progress in development of a selective thyroid hormone receptor modulator, GC-1. This compound binds selectively to the beta-isoform of the thyroid hormone receptor, and its uptake into the heart is relatively low. Studies in rats, mice and monkeys show that GC-1 lowers cholesterol with 600- to 1400-fold more potency and approximately two- to threefold more efficacy than atorvastatin, a compound that blocks HMG-CoA reductase. GC-1 also decreases plasma levels of triglyceride and lipoprotein (a), and induces loss of fat. These effects can be observed under conditions where there is either no or minimal effect on heart rate, and no detectable loss of muscle. Although more study is required, compounds of this class deserve further investigation for treating lipid disorders and obesity.
Collapse
Affiliation(s)
- John D Baxter
- Diabetes Center and Department of Medicine, University of California-San Francisco, San Francisco, CA 94143-0540, USA.
| | | | | | | |
Collapse
|
30
|
Smith CL, O'Malley BW. Coregulator function: a key to understanding tissue specificity of selective receptor modulators. Endocr Rev 2004; 25:45-71. [PMID: 14769827 DOI: 10.1210/er.2003-0023] [Citation(s) in RCA: 640] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Ligands for the nuclear receptor superfamily control many aspects of biology, including development, reproduction, and homeostasis, through regulation of the transcriptional activity of their cognate receptors. Selective receptor modulators (SRMs) are receptor ligands that exhibit agonistic or antagonistic biocharacter in a cell- and tissue context-dependent manner. The prototypical SRM is tamoxifen, which as a selective estrogen receptor modulator, can activate or inhibit estrogen receptor action. SRM-induced alterations in the conformation of the ligand-binding domains of nuclear receptors influence their abilities to interact with other proteins, such as coactivators and corepressors. It has been postulated, therefore, that the relative balance of coactivator and corepressor expression within a given target cell determines the relative agonist vs. antagonist activity of SRMs. However, recent evidence reveals that the cellular environment also plays a critical role in determining SRM biocharacter. Cellular signaling influences the activity and subcellular localization of coactivators and corepressors as well as nuclear receptors, and this contributes to gene-, cell-, and tissue-specific responses to SRM ligands. Increased understanding of the effect of cellular environment on nuclear receptors and their coregulators has the potential to open the field of SRM discovery and research to many members of the nuclear receptor superfamily.
Collapse
Affiliation(s)
- Carolyn L Smith
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030, USA.
| | | |
Collapse
|