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Lu Y, Chen C, Zhuang D, Qian L. Molecular Dynamic Simulation To Reveal the Mechanism Underlying MGL-3196 Resistance to Thyroxine Receptor Beta. ACS OMEGA 2024; 9:20957-20965. [PMID: 38764645 PMCID: PMC11097192 DOI: 10.1021/acsomega.4c00089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 04/17/2024] [Accepted: 04/19/2024] [Indexed: 05/21/2024]
Abstract
Thyroxine receptor beta (TRβ) is a ligand-dependent nuclear receptor that participates in regulating multiple biological processes, particularly playing an important role in lipid metabolism regulation. TRβ is currently a popular therapeutic target for nonalcoholic steatohepatitis (NASH), while no drugs have been approved to treat this disease. MGL-3196 (Resmetirom) is the first TRβ agonist that has succeeded in phase III clinical trials for the treatment of NASH; therefore, studying its molecular mechanism of action is of great significance. In this study, we employed molecular dynamic simulation to investigate the interaction mode between MGL-3196 and TRβ at the all-atom level. More importantly, by comparing the binding patterns of MGL-3196 in several prevalent TRβ mutants, it was identified that the mutations R243Q and H435R located, respectively, around and within the ligand-binding pocket of TRβ cause TRβ to be insensitive to MGL-3196. This indicates that patients with NASH carrying these two mutations may exhibit resistance to the medication of MGL-3196, thereby highlighting the potential impact of TRβ mutations on TRβ-targeted treatment of NASH and beyond.
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Affiliation(s)
- Yi Lu
- Fujian
Key Laboratory of Neonatal Diseases, Xiamen Key Laboratory of Neonatal
Diseases, Xiamen Childreǹs Hospital
(Children’s Hospital of Fudan University at Xiamen), Xiamen 361006, China
- Department
of Pediatrics, Chidren’s Hospital
of Fudan University, Shanghai 201102, China
| | - Chun Chen
- Fujian
Key Laboratory of Neonatal Diseases, Xiamen Key Laboratory of Neonatal
Diseases, Xiamen Childreǹs Hospital
(Children’s Hospital of Fudan University at Xiamen), Xiamen 361006, China
| | - Deyi Zhuang
- Fujian
Key Laboratory of Neonatal Diseases, Xiamen Key Laboratory of Neonatal
Diseases, Xiamen Childreǹs Hospital
(Children’s Hospital of Fudan University at Xiamen), Xiamen 361006, China
| | - Liling Qian
- Fujian
Key Laboratory of Neonatal Diseases, Xiamen Key Laboratory of Neonatal
Diseases, Xiamen Childreǹs Hospital
(Children’s Hospital of Fudan University at Xiamen), Xiamen 361006, China
- Division
of Pulmonary Medicine, Shanghai Children’s Hospital, School
of Medicine, Shanghai Jiao Tong University, Shanghai 200062, China
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2
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Fischer A, Frehner G, Lill MA, Smieško M. Conformational Changes of Thyroid Receptors in Response to Antagonists. J Chem Inf Model 2021; 61:1010-1019. [PMID: 33449688 DOI: 10.1021/acs.jcim.0c01403] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Thyroid hormone receptors (TRs) play a critical role in human development, growth, and metabolism. Antagonists of TRs offer an attractive strategy to treat hyperthyroidism without the disadvantage of a delayed onset of drug action. While it is challenging to examine the atomistic behavior of TRs in a laboratory setting, computational methods such as molecular dynamics (MD) simulations have proven their value to elucidate ligand-induced conformational changes in nuclear receptors. Here, we performed MD simulations of TRα and TRβ complexed to their native ligand triiodothyronine (T3) as well as several antagonists. Based on the examination of 27 μs MD trajectories, we showed how binding of these compounds influences various structural features of the receptors including the helicity of helices 3 and 10 as well as the location of helix-12. Helices 3 and 12 are known to mediate coactivator association required for downstream signaling, suggesting these changes to be the molecular basis for TR antagonism. A mechanistic analysis of the trajectories revealed an allosteric pathway between H3 and H12 to be responsible for the conformational adaptations. Even though a mechanistic understanding of conformational adaptations triggered by TR antagonists is important for the development of novel therapeutics, they have not been previously examined in detail as it was done here.
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Affiliation(s)
- André Fischer
- Computational Pharmacy, Department of Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 61, Basel 4056, Switzerland
| | - Gabriela Frehner
- Computational Pharmacy, Department of Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 61, Basel 4056, Switzerland
| | - Markus A Lill
- Computational Pharmacy, Department of Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 61, Basel 4056, Switzerland
| | - Martin Smieško
- Computational Pharmacy, Department of Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 61, Basel 4056, Switzerland
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3
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Chen Q, Wang X, Shi W, Yu H, Zhang X, Giesy JP. Identification of Thyroid Hormone Disruptors among HO-PBDEs: In Vitro Investigations and Coregulator Involved Simulations. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:12429-12438. [PMID: 27737548 DOI: 10.1021/acs.est.6b02029] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Some hydroxylated polybrominated diphenyl ethers (HO-PBDEs), that have been widely detected in the environment and tissues of humans and wildlife, bind to thyroid hormone (TH) receptor (TR) and can disrupt functioning of systems modulated by the TR. However, mechanisms of TH disrupting effects are still equivocal. Here, disruption of functions of TH modulated pathways by HO-PBDEs was evaluated by assays of competitive binding, coactivator recruitment, and proliferation of GH3 cells. In silico simulations considering effects of coregulators were carried out to investigate molecular mechanisms and to predict potencies for disrupting functions of the TH. Some HO-PBDEs were able to bind to TR with moderate affinities but were not agonists. In GH3 proliferation assays, 13 out of 16 HO-PBDEs were antagonists for the TH. In silico simulations of molecular dynamics revealed that coregulators were essential for identification of TH disruptors. Among HO-PBDEs, binding of passive antagonists induced repositioning of H12, blocking AF-2 (transactivation function 2) and preventing recruitment of the coactivator. Binding of active antagonists exposed the coregulator binding site, which tended to bind to the corepressor rather than the coactivator. By considering both passive and active antagonisms, anti-TH potencies of HO-PBDEs could be predicted from free energy of binding.
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Affiliation(s)
- Qinchang Chen
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University , Nanjing 210023, PR China
| | - Xiaoxiang Wang
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University , Nanjing 210023, PR China
- Multiphase Chemistry Department, Max Planck Institute for Chemistry , 55128 Mainz, Germany
| | - Wei Shi
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University , Nanjing 210023, PR China
| | - Hongxia Yu
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University , Nanjing 210023, PR China
| | - Xiaowei Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University , Nanjing 210023, PR China
| | - John P Giesy
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University , Nanjing 210023, PR China
- Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5B4, Canada
- Department of Zoology and Center for Integrative Toxicology, Michigan State University , East Lansing, Michigan 48824, United States
- School of Biological Sciences, University of Hong Kong , Hong Kong, SAR, China
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4
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Ortiga-Carvalho TM, Chiamolera MI, Pazos-Moura CC, Wondisford FE. Hypothalamus-Pituitary-Thyroid Axis. Compr Physiol 2016; 6:1387-428. [PMID: 27347897 DOI: 10.1002/cphy.c150027] [Citation(s) in RCA: 200] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The hypothalamus-pituitary-thyroid (HPT) axis determines the set point of thyroid hormone (TH) production. Hypothalamic thyrotropin-releasing hormone (TRH) stimulates the synthesis and secretion of pituitary thyrotropin (thyroid-stimulating hormone, TSH), which acts at the thyroid to stimulate all steps of TH biosynthesis and secretion. The THs thyroxine (T4) and triiodothyronine (T3) control the secretion of TRH and TSH by negative feedback to maintain physiological levels of the main hormones of the HPT axis. Reduction of circulating TH levels due to primary thyroid failure results in increased TRH and TSH production, whereas the opposite occurs when circulating THs are in excess. Other neural, humoral, and local factors modulate the HPT axis and, in specific situations, determine alterations in the physiological function of the axis. The roles of THs are vital to nervous system development, linear growth, energetic metabolism, and thermogenesis. THs also regulate the hepatic metabolism of nutrients, fluid balance and the cardiovascular system. In cells, TH actions are mediated mainly by nuclear TH receptors (210), which modify gene expression. T3 is the preferred ligand of THR, whereas T4, the serum concentration of which is 100-fold higher than that of T3, undergoes extra-thyroidal conversion to T3. This conversion is catalyzed by 5'-deiodinases (D1 and D2), which are TH-activating enzymes. T4 can also be inactivated by conversion to reverse T3, which has very low affinity for THR, by 5-deiodinase (D3). The regulation of deiodinases, particularly D2, and TH transporters at the cell membrane control T3 availability, which is fundamental for TH action. © 2016 American Physiological Society. Compr Physiol 6:1387-1428, 2016.
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Affiliation(s)
- Tania M Ortiga-Carvalho
- Institute of Biophysics Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, UFRJ, Rio de Janeiro, Brazil
| | - Maria I Chiamolera
- Department of Medicine, Escola Paulista de Medicina, Universidade Federal de Sao Paulo, Sao Paulo, Brazil
| | - Carmen C Pazos-Moura
- Institute of Biophysics Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, UFRJ, Rio de Janeiro, Brazil
| | - Fredic E Wondisford
- Department of Medicine, Rutgers-Robert Wood Johnson Medical School, New Brunswick, New Jersey, USA
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5
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Batista MRB, Martínez L. Conformational Diversity of the Helix 12 of the Ligand Binding Domain of PPARγ and Functional Implications. J Phys Chem B 2015; 119:15418-29. [DOI: 10.1021/acs.jpcb.5b09824] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Mariana R. B. Batista
- Department of Physical Chemistry,
Institute of Chemistry, University of Campinas, CP 6154-13083-970, Campinas, SP Brazil
| | - Leandro Martínez
- Department of Physical Chemistry,
Institute of Chemistry, University of Campinas, CP 6154-13083-970, Campinas, SP Brazil
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6
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Ortiga-Carvalho TM, Sidhaye AR, Wondisford FE. Thyroid hormone receptors and resistance to thyroid hormone disorders. Nat Rev Endocrinol 2014; 10:582-91. [PMID: 25135573 PMCID: PMC4578869 DOI: 10.1038/nrendo.2014.143] [Citation(s) in RCA: 191] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Thyroid hormone action is predominantly mediated by thyroid hormone receptors (THRs), which are encoded by the thyroid hormone receptor α (THRA) and thyroid hormone receptor β (THRB) genes. Patients with mutations in THRB present with resistance to thyroid hormone β (RTHβ), which is a disorder characterized by elevated levels of thyroid hormone, normal or elevated levels of TSH and goitre. Mechanistic insights about the contributions of THRβ to various processes, including colour vision, development of the cochlea and the cerebellum, and normal functioning of the adult liver and heart, have been obtained by either introducing human THRB mutations into mice or by deletion of the mouse Thrb gene. The introduction of the same mutations that mimic human THRβ alterations into the mouse Thra and Thrb genes resulted in distinct phenotypes, which suggests that THRA and THRB might have non-overlapping functions in human physiology. These studies also suggested that THRA mutations might not be lethal. Seven patients with mutations in THRα have since been described. These patients have RTHα and presented with major abnormalities in growth and gastrointestinal function. The hypothalamic-pituitary-thyroid axis in these individuals is minimally affected, which suggests that the central T3 feedback loop is not impaired in patients with RTHα, in stark contrast to patients with RTHβ.
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Affiliation(s)
- Tânia M Ortiga-Carvalho
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, S/N, Cidade Universitária, 21941-902, Rio de Janeiro, Brazil
| | - Aniket R Sidhaye
- Departments of Paediatrics and Medicine, Johns Hopkins University School of Medicine, 600 N. Wolfe Street, CMSC 10-113, Baltimore, MD 21287, USA
| | - Fredric E Wondisford
- Departments of Paediatrics and Medicine, Johns Hopkins University School of Medicine, 600 N. Wolfe Street, CMSC 10-113, Baltimore, MD 21287, USA
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7
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Mackinnon JAG, Gallastegui N, Osguthorpe DJ, Hagler AT, Estébanez-Perpiñá E. Allosteric mechanisms of nuclear receptors: insights from computational simulations. Mol Cell Endocrinol 2014; 393:75-82. [PMID: 24911885 DOI: 10.1016/j.mce.2014.05.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 05/15/2014] [Accepted: 05/19/2014] [Indexed: 01/07/2023]
Abstract
The traditional structural view of allostery defines this key regulatory mechanism as the ability of one conformational event (allosteric site) to initiate another in a separate location (active site). In recent years computational simulations conducted to understand how this phenomenon occurs in nuclear receptors (NRs) has gained significant traction. These results have yield insights into allosteric changes and communication mechanisms that underpin ligand binding, coactivator binding site formation, post-translational modifications, and oncogenic mutations. Moreover, substantial efforts have been made in understanding the dynamic processes involved in ligand binding and coregulator recruitment to different NR conformations in order to predict cell/tissue-selective pharmacological outcomes of drugs. They also have improved the accuracy of in silico screening protocols so that nowadays they are becoming part of optimisation protocols for novel therapeutics. Here we summarise the important contributions that computational simulations have made towards understanding the structure/function relationships of NRs and how these can be exploited for rational drug design.
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Affiliation(s)
- Jonathan A G Mackinnon
- Institute of Biomedicine of the University of Barcelona (IBUB), Department of Biochemistry and Molecular Biology, University of Barcelona (UB), Baldiri-Reixac 15-21, 08028 Barcelona, Spain
| | - Nerea Gallastegui
- Institute of Biomedicine of the University of Barcelona (IBUB), Department of Biochemistry and Molecular Biology, University of Barcelona (UB), Baldiri-Reixac 15-21, 08028 Barcelona, Spain
| | - David J Osguthorpe
- Shifa Biomedical, 1 Great Valley Parkway, Suite 8, Malvern, PA 19355, USA
| | - Arnold T Hagler
- Department of Chemistry, University of Massachusetts, 701 Lederle, Graduate Research Tower, 710 North Pleasant Street, Amherst, MA 01003-9336, USA.
| | - Eva Estébanez-Perpiñá
- Institute of Biomedicine of the University of Barcelona (IBUB), Department of Biochemistry and Molecular Biology, University of Barcelona (UB), Baldiri-Reixac 15-21, 08028 Barcelona, Spain.
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8
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Determinants of protein–ligand complex formation in the thyroid hormone receptor α: A molecular dynamics simulation study. COMPUT THEOR CHEM 2014. [DOI: 10.1016/j.comptc.2014.03.034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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9
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Souza PCT, Puhl AC, Martínez L, Aparício R, Nascimento AS, Figueira ACM, Nguyen P, Webb P, Skaf MS, Polikarpov I. Identification of a new hormone-binding site on the surface of thyroid hormone receptor. Mol Endocrinol 2014; 28:534-45. [PMID: 24552590 DOI: 10.1210/me.2013-1359] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Thyroid hormone receptors (TRs) are members of the nuclear receptor superfamily of ligand-activated transcription factors involved in cell differentiation, growth, and homeostasis. Although X-ray structures of many nuclear receptor ligand-binding domains (LBDs) reveal that the ligand binds within the hydrophobic core of the ligand-binding pocket, a few studies suggest the possibility of ligands binding to other sites. Here, we report a new x-ray crystallographic structure of TR-LBD that shows a second binding site for T3 and T4 located between H9, H10, and H11 of the TRα LBD surface. Statistical multiple sequence analysis, site-directed mutagenesis, and cell transactivation assays indicate that residues of the second binding site could be important for the TR function. We also conducted molecular dynamics simulations to investigate ligand mobility and ligand-protein interaction for T3 and T4 bound to this new TR surface-binding site. Extensive molecular dynamics simulations designed to compute ligand-protein dissociation constant indicate that the binding affinities to this surface site are of the order of the plasma and intracellular concentrations of the thyroid hormones, suggesting that ligands may bind to this new binding site under physiological conditions. Therefore, the second binding site could be useful as a new target site for drug design and could modulate selectively TR functions.
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Affiliation(s)
- P C T Souza
- Institute of Chemistry (P.C.T.S., L.M., R.A., M.S.S.), State University of Campinas-UNICAMP, Campinas, Sao Paulo, Brazil; Institute of Physics of São Carlos (A.C.P., A.S.N., P.W., I.P.), University of São Paulo-USP, São Carlos, Sao Paulo, Brazil; National Laboratory of Biosciences (A.C.M.F.), CNPEM, Campinas, Sao Paulo, Brazil; University of California Medical Center (P.N.), Diabetes Center, San Francisco, California; and Genomic Medicine (P.W.), Houston Methodist Research Institute, Houston, Texas
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10
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Shi C, Meng Q, Wood DW. Analysis of the roles of mutations in thyroid hormone receptor-β by a bacterial biosensor system. J Mol Endocrinol 2014; 52:55-66. [PMID: 24174637 DOI: 10.1530/jme-13-0108] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Mutations in thyroid hormone receptors (TRs) often lead to metabolic and developmental disorders, but patients with these mutations are difficult to treat with existing thyromimetic drugs. In this study, we analyzed six clinically observed mutations in the ligand-binding domain of the human TRβ using an engineered bacterial hormone biosensor. Six agonist compounds, including triiodothyronine (T3), thyroxine (T4), 3,5,3'-triiodothyroacetic acid (Triac), GC-1, KB-141, and CO-23, and the antagonist NH-3 were examined for their ability to bind to each of the TRβ mutants. The results indicate that some mutations lead to the loss of ability to bind to native ligands, ranging from several fold to several hundred fold, while other mutations completely abolish the ability to bind to any ligand. Notably, the effect of each ligand on each TRβ mutant in this bacterial system is highly dependent on both the mutation and the ligand; some ligands were bound well by a wide variety of mutants, while other ligands lost their affinity for all but the WT receptor. This study demonstrates the ability of our bacterial system to differentiate agonist compounds from antagonist compounds and shows that one of the TRβ mutations leads to an unexpected increase in antagonist ability relative to other mutations. These results indicate that this bacterial sensor can be used to rapidly determine ligand-binding ability and character for clinically relevant TRβ mutants.
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Affiliation(s)
- Changhua Shi
- Institute of Biological Sciences and Biotechnology, Donghua University, Shanghai 201620, People's Republic of China Department of Chemical and Biomolecular Engineering, Ohio State University, Columbus, Ohio 43210, USA
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Dong J, Qiu J, Zhang Y, Lu C, Dai X, Wang J, Li H, Wang X, Tan W, Luo M, Niu X, Deng X. Oroxylin A inhibits hemolysis via hindering the self-assembly of α-hemolysin heptameric transmembrane pore. PLoS Comput Biol 2013; 9:e1002869. [PMID: 23349625 PMCID: PMC3547825 DOI: 10.1371/journal.pcbi.1002869] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 11/16/2012] [Indexed: 02/06/2023] Open
Abstract
Alpha-hemolysin (α-HL) is a self-assembling, channel-forming toxin produced by most Staphylococcus aureus strains as a 33.2-kDa soluble monomer. Upon binding to a susceptible cell membrane, the monomer self-assembles to form a 232.4-kDa heptamer that ultimately causes host cell lysis and death. Consequently, α-HL plays a significant role in the pathogenesis of S. aureus infections, such as pneumonia, mastitis, keratitis and arthritis. In this paper, experimental studies show that oroxylin A (ORO), a natural compound without anti-S. aureus activity, can inhibit the hemolytic activity of α-HL. Molecular dynamics simulations, free energy calculations, and mutagenesis assays were performed to understand the formation of the α-HL-ORO complex. This combined approach revealed that the catalytic mechanism of inhibition involves the direct binding of ORO to α-HL, which blocks the conformational transition of the critical “Loop” region of the α-HL protein thereby inhibiting its hemolytic activity. This mechanism was confirmed by experimental data obtained from a deoxycholate-induced oligomerization assay. It was also found that, in a co-culture system with S. aureus and human alveolar epithelial (A549) cells, ORO could protect against α-HL-mediated injury. These findings indicate that ORO hinders the lytic activity of α-HL through a novel mechanism, which should facilitate the design of new and more effective antibacterial agents against S. aureus. The mechanism controlling protein-ligand interactions is one of the most important processes in rational drug design. X-ray crystallography is a traditional tool used to investigate the interaction of ligands and proteins in a complex. However, protein crystallography is inefficient, and the development of crystal technology and research remains unequally distributed. Thus, it seems impractical to explore the structure of the α-hemolysin-ORO monomer complex by crystallography. Therefore, we used molecular dynamics simulations to investigate the receptor-ligand interaction in the α-HL-ORO monomer complex. In this study, we found that oroxylin A (ORO), a natural compound with little anti-S. aureus activity, can inhibit the hemolytic activity of α-HL at low concentrations. Through molecular docking and molecular dynamics simulations, we determined the potential binding mode of the protein-ligand interaction. The data revealed that ORO directly binds to α-HL, an interaction that blacks the conformational transition of the critical “Loop” region in α-HL and thus prevents the formation of the α-HL heptameric transmembrane pore, which ultimately inhibits the hemolytic activity of α-HL. This mechanism was confirmed by experimental data. Furthermore, we demonstrated that ORO could protect against α-HL-mediated injury in human alveolar epithelial (A549) cells.
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Affiliation(s)
- Jing Dong
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
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12
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Abstract
Our understanding of thyroid hormone action has been substantially altered by recent clinical observations of thyroid signaling defects in syndromes of hormone resistance and in a broad range of conditions, including profound mental retardation, obesity, metabolic disorders, and a number of cancers. The mechanism of thyroid hormone action has been informed by these clinical observations as well as by animal models and has influenced the way we view the role of local ligand availability; tissue and cell-specific thyroid hormone transporters, corepressors, and coactivators; thyroid hormone receptor (TR) isoform-specific action; and cross-talk in metabolic regulation and neural development. In some cases, our new understanding has already been translated into therapeutic strategies, especially for treating hyperlipidemia and obesity, and other drugs are in development to treat cardiac disease and cancer and to improve cognitive function.
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Affiliation(s)
- Gregory A Brent
- Department of Medicine, VA Greater Los Angeles Healthcare System, David Geffen School of Medicine at UCLA, Los Angeles, CA 90073, USA.
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13
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Lukman S, Robinson RC, Wales D, Verma CS. Conformational dynamics of capping protein and interaction partners: Simulation studies. Proteins 2012; 80:1066-77. [DOI: 10.1002/prot.24008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 11/11/2011] [Accepted: 11/18/2011] [Indexed: 11/09/2022]
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