1
|
Valcárcel-Hernández V, Vancamp P, Butruille L, Remaud S, Guadaño-Ferraz A. Combined deletion of Mct8 and Dio2 impairs SVZ neurogliogenesis and olfactory function in adult mice. Neurobiol Dis 2024; 199:106572. [PMID: 38901782 DOI: 10.1016/j.nbd.2024.106572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 05/30/2024] [Accepted: 06/16/2024] [Indexed: 06/22/2024] Open
Abstract
Within the adult mouse subventricular zone (SVZ), neural stem cells (NSCs) produce neuroblasts and oligodendrocyte precursor cells (OPCs). T3, the active thyroid hormone, influences renewal and commitment of SVZ progenitors. However, how regulators of T3 availability affect these processes is less understood. Using Mct8/Dio2 knockout mice, we investigated the role of MCT8, a TH transporter, and DIO2, the T3-generating enzyme, in regulating adult SVZ-neurogliogenesis. Single-cell RNA-Seq revealed Mct8 expression in various SVZ cell types in WT mice, while Dio2 was enriched in neurons, astrocytes, and quiescent NSCs. The absence of both regulators in the knockout model dysregulated gene expression, increased the neuroblast/OPC ratio and hindered OPC differentiation. Immunostainings demonstrated compromised neuroblast migration reducing their supply to the olfactory bulbs, impairing interneuron differentiation and odor discrimination. These findings underscore the pivotal roles of MCT8 and DIO2 in neuro- and oligodendrogenesis, offering targets for therapeutic avenues in neurodegenerative and demyelinating diseases.
Collapse
Affiliation(s)
- Víctor Valcárcel-Hernández
- Laboratory of Thyroid hormones and CNS, Department of Neurological Diseases and Aging, Instituto de Investigaciones Biomédicas Sols-Morreale, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Arturo Duperier 4, 28029 Madrid, Spain; Laboratory of Molecular Physiology and Adaptation, CNRS UMR 7221, Department Adaptations of Life, Muséum National d'Histoire Naturelle, F-75005 Paris, France
| | - Pieter Vancamp
- Laboratory of Molecular Physiology and Adaptation, CNRS UMR 7221, Department Adaptations of Life, Muséum National d'Histoire Naturelle, F-75005 Paris, France
| | - Lucile Butruille
- Laboratory of Molecular Physiology and Adaptation, CNRS UMR 7221, Department Adaptations of Life, Muséum National d'Histoire Naturelle, F-75005 Paris, France
| | - Sylvie Remaud
- Laboratory of Molecular Physiology and Adaptation, CNRS UMR 7221, Department Adaptations of Life, Muséum National d'Histoire Naturelle, F-75005 Paris, France.
| | - Ana Guadaño-Ferraz
- Laboratory of Thyroid hormones and CNS, Department of Neurological Diseases and Aging, Instituto de Investigaciones Biomédicas Sols-Morreale, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Arturo Duperier 4, 28029 Madrid, Spain.
| |
Collapse
|
2
|
Moran C, Schoenmakers N, Visser WE, Schoenmakers E, Agostini M, Chatterjee K. Genetic disorders of thyroid development, hormone biosynthesis and signalling. Clin Endocrinol (Oxf) 2022; 97:502-514. [PMID: 35999191 PMCID: PMC9544560 DOI: 10.1111/cen.14817] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 05/24/2022] [Accepted: 07/04/2022] [Indexed: 11/28/2022]
Abstract
Development and differentiation of the thyroid gland is directed by expression of specific transcription factors in the thyroid follicular cell which mediates hormone biosynthesis. Membrane transporters are rate-limiting for cellular entry of thyroid hormones (TH) (T4 and T3) into some tissues, with selenocysteine-containing, deiodinase enzymes (DIO1 and DIO2) converting T4 to the biologically active hormone T3. TH regulate expression of target genes via hormone-inducible nuclear receptors (TRα and TRβ) to exert their physiological effects. Primary congenital hypothyroidism (CH) due to thyroid dysgenesis may be mediated by defects in thyroid transcription factors or impaired thyroid stimulating hormone receptor function. Dyshormonogenic CH is usually due to mutations in genes mediating thyroidal iodide transport, organification or iodotyrosine synthesis and recycling. Disorders of TH signalling encompass conditions due to defects in membrane TH transporters, impaired hormone metabolism due to deficiency of deiodinases and syndromes of Resistance to thyroid hormone due to pathogenic variants in either TRα or TRβ. Here, we review the genetic basis, pathogenesis and clinical features of congenital, dysgenetic or dyshormonogenic hypothyroidism and disorders of TH transport, metabolism and action.
Collapse
Affiliation(s)
- Carla Moran
- Wellcome Trust‐MRC Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
- Present address:
Beacon Hospital and School of MedicineUniversity CollegeDublinIreland
| | - Nadia Schoenmakers
- Wellcome Trust‐MRC Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
| | - W. Edward Visser
- Department of Internal MedicineErasmus Medical Center, Academic Center for Thyroid DiseasesRotterdamThe Netherlands
| | - Erik Schoenmakers
- Wellcome Trust‐MRC Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
| | - Maura Agostini
- Wellcome Trust‐MRC Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
| | - Krishna Chatterjee
- Wellcome Trust‐MRC Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
| |
Collapse
|
3
|
Yao B, Yang C, Pan C, Li Y. Thyroid hormone resistance: Mechanisms and therapeutic development. Mol Cell Endocrinol 2022; 553:111679. [PMID: 35738449 DOI: 10.1016/j.mce.2022.111679] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 05/03/2021] [Accepted: 05/09/2022] [Indexed: 10/18/2022]
Abstract
As an essential primary hormone, thyroid hormone (TH) is indispensable for human growth, development and metabolism. Impairment of TH function in several aspects, including TH synthesis, activation, transportation and receptor-dependent transactivation, can eventually lead to thyroid hormone resistance syndrome (RTH). RTH is a rare syndrome that manifests as a reduced target cell response to TH signaling. The majority of RTH cases are related to thyroid hormone receptor β (TRβ) mutations, and only a few RTH cases are associated with thyroid hormone receptor α (TRα) mutations or other causes. Patients with RTH suffer from goiter, mental retardation, short stature and bradycardia or tachycardia. To date, approximately 170 mutated TRβ variants and more than 20 mutated TRα variants at the amino acid level have been reported in RTH patients. In addition to these mutated proteins, some TR isoforms can also reduce TH function by competing with primary TRs for TRE and RXR binding. Fortunately, different treatments for RTH have been explored with structure-activity relationship (SAR) studies and drug design, and among these treatments. With thyromimetic potency but biochemical properties that differ from those of primary TH (T3 and T4), these TH analogs can bypass specific defective transporters or reactive mutant TRs. However, these compounds must be carefully applied to avoid over activating TRα, which is associated with more severe heart impairment. The structural mechanisms of mutation-induced RTH in the TR ligand-binding domain are summarized in this review. Furthermore, strategies to overcome this resistance for therapeutic development are also discussed.
Collapse
Affiliation(s)
- Benqiang Yao
- The State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Signaling Network, School of Life Sciences, Xiamen University, Fujian, 361005, China
| | - Chunyan Yang
- The State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Signaling Network, School of Life Sciences, Xiamen University, Fujian, 361005, China.
| | - Chengxi Pan
- The State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Signaling Network, School of Life Sciences, Xiamen University, Fujian, 361005, China
| | - Yong Li
- The State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Signaling Network, School of Life Sciences, Xiamen University, Fujian, 361005, China.
| |
Collapse
|
4
|
Liao XH, Avalos P, Shelest O, Ofan R, Shilo M, Bresee C, Likhite S, Vit JP, Heuer H, Kaspar B, Meyer K, Dumitrescu AM, Refetoff S, Svendsen CN, Vatine GD. AAV9-MCT8 Delivery at Juvenile Stage Ameliorates Neurological and Behavioral Deficits in a Mouse Model of MCT8-Deficiency. Thyroid 2022; 32:849-859. [PMID: 35350867 PMCID: PMC9469747 DOI: 10.1089/thy.2022.0034] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Background: Allan-Herndon-Dudley syndrome (AHDS) is a severe psychomotor disability disorder that also manifests characteristic abnormal thyroid hormone (TH) levels. AHDS is caused by inactivating mutations in monocarboxylate transporter 8 (MCT8), a specific TH plasma membrane transporter widely expressed in the central nervous system (CNS). MCT8 mutations cause impaired transport of TH across brain barriers, leading to insufficient neural TH supply. There is currently no successful therapy for the neurological symptoms. Earlier work has shown that intravenous (IV), but not intracerebroventricular adeno-associated virus serotype 9 (AAV9) -based gene therapy given to newborn Mct8 knockout (Mct8-/y) male mice increased triiodothyronine (T3) brain content and partially rescued TH-dependent gene expression, suggesting a promising approach to treat this neurological disorder. Methods: The potential of IV delivery of AAV9 carrying human MCT8 was tested in the well-established Mct8-/y/Organic anion-transporting polypeptide 1c1 (Oatp1c1)-/ - double knockout (dKO) mouse model of AHDS, which, unlike Mct8-/y mice, displays both neurological and TH phenotype. Further, as the condition is usually diagnosed during childhood, treatment was given intravenously to P30 mice and psychomotor tests were carried out blindly at P120-P140 after which tissues were collected and analyzed. Results: Systemic IV delivery of AAV9-MCT8 at a juvenile stage led to improved locomotor and cognitive functions at P120-P140, which was accompanied by a near normalization of T3 content and an increased response of positively regulated TH-dependent gene expression in different brain regions examined (thalamus, hippocampus, and parietal cortex). The effects on serum TH concentrations and peripheral tissues were less pronounced, showing only improvement in the serum T3/reverse T3 (rT3) ratio and in liver deiodinase 1 expression. Conclusion: IV administration of AAV9, carrying the human MCT8, to juvenile dKO mice manifesting AHDS has long-term beneficial effects, predominantly on the CNS. This preclinical study indicates that this gene therapy has the potential to ameliorate the devastating neurological symptoms in patients with AHDS.
Collapse
Affiliation(s)
- Xiao-Hui Liao
- Department of Medicine, The University of Chicago, Chicago, Illinois, USA
| | - Pablo Avalos
- The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Oksana Shelest
- The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Raz Ofan
- Department of Biotechnology Engineering, Faculty of Engineering Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
- The Regenerative Medicine and Stem Cell (RMSC) Research Center, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Michael Shilo
- Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Catherine Bresee
- Biostatistics Core, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Shibi Likhite
- The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, USA
| | - Jean-Philippe Vit
- The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Heike Heuer
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, Essen, Germany
| | - Brian Kaspar
- The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, USA
| | - Kathrin Meyer
- The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, USA
| | | | - Samuel Refetoff
- Department of Medicine, The University of Chicago, Chicago, Illinois, USA
- Department of Pediatrics, The University of Chicago, Chicago, Illinois, USA
- Committee on Genetics, The University of Chicago, Chicago, Illinois, USA
- Address correspondence to: Samuel Refetoff, MD, Department of Medicine, The University of Chicago, MC3090, 5841 South Maryland Avenue, Chicago, IL 60637, USA
| | - Clive N. Svendsen
- The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
- Address correspondence to: Clive N. Svendsen, PhD, The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd, Los Angeles, CA 90048, USA
| | - Gad D. Vatine
- The Regenerative Medicine and Stem Cell (RMSC) Research Center, Ben-Gurion University of the Negev, Beer Sheva, Israel
- Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
- The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer Sheva, Israel
- Address correspondence to: Gad D. Vatine, PhD, Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel
| |
Collapse
|
5
|
Braun D, Bohleber S, Vatine GD, Svendsen CN, Schweizer U. Sodium Phenylbutyrate Rescues Thyroid Hormone Transport in Brain Endothelial-Like Cells. Thyroid 2022; 32:860-870. [PMID: 35357974 DOI: 10.1089/thy.2021.0643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Background: Monocarboxylate transporter 8 (MCT8) deficiency is a rare genetic disease leading to a severe developmental delay due to a lack of thyroid hormones (THs) during critical stages of human brain development. Some MCT8-deficient patients are not as severely affected as others. Previously, we hypothesized that these patients' mutations do not affect the functionality but destabilize the MCT8 protein, leading to a diminished number of functional MCT8 molecules at the cell surface. Methods: We have already demonstrated that the chemical chaperone sodium phenylbutyrate (NaPB) rescues the function of these mutants by stabilizing their protein expression in an overexpressing cell system. Here, we expanded our previous work and used iPSC (induced pluripotent stem cell)-derived brain microvascular endothelial-like cells (iBMECs) as a physiologically relevant cell model of human origin to test for NaPB responsiveness. The effects on mutant MCT8 expression and function were tested by Western blotting and radioactive uptake assays. Results: We found that NaPB rescues decreased mutant MCT8 expression and restores transport function in iBMECs carrying patient's mutation MCT8-P321L. Further, we identified MCT10 as an alternative TH transporter in iBMECs that contributes to triiodothyronine uptake, the biological active TH. Our results indicate an upregulation of MCT10 after NaPB treatment. In addition, we detected an increase in thyroxine (T4) uptake after NaPB treatment that was not mediated by rescued MCT8 but an unidentified T4 transporter. Conclusions: We demonstrate that NaPB is suitable to stabilize a pathogenic missense mutation in a human-derived cell model. Further, it activates TH transport independent of MCT8. Both options fuel future studies to investigate repurposing the Food and Drug Administration-approved drug NaPB in selected cases of MCT8 deficiency.
Collapse
Affiliation(s)
- Doreen Braun
- Institut für Biochemie und Molekularbiologie, Medizinische Fakultät, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Simon Bohleber
- Institut für Biochemie und Molekularbiologie, Medizinische Fakultät, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Gad D Vatine
- The Department of Physiology and Cell Biology, Faculty of Health Sciences, The Regenerative Medicine and Stem Cell (RMSC) Research Center and the Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer Sheva, Israel
- Department of Biomedical Sciences, The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Clive N Svendsen
- Department of Biomedical Sciences, The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Ulrich Schweizer
- Institut für Biochemie und Molekularbiologie, Medizinische Fakultät, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| |
Collapse
|
6
|
Chaudhary P, Marracci GH, Calkins E, Pocius E, Bensen AL, Scanlan TS, Emery B, Bourdette DN. Thyroid hormone and thyromimetics inhibit myelin and axonal degeneration and oligodendrocyte loss in EAE. J Neuroimmunol 2021; 352:577468. [PMID: 33422763 PMCID: PMC8748188 DOI: 10.1016/j.jneuroim.2020.577468] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 12/20/2020] [Accepted: 12/21/2020] [Indexed: 12/21/2022]
Abstract
We have previously demonstrated that thyromimetics stimulate oligodendrocyte precursor cell differentiation and promote remyelination in murine demyelination models. We investigated whether a thyroid receptor-beta selective thyromimetic, sobetirome (Sob), and its CNS-targeted prodrug, Sob-AM2, could prevent myelin and axonal degeneration in experimental autoimmune encephalomyelitis (EAE). Compared to controls, EAE mice receiving triiodothyronine (T3, 0.4 mg/kg), Sob (5 mg/kg) or Sob-AM2 (5 mg/kg) had reduced clinical disease and, within the spinal cord, less tissue damage, more normally myelinated axons, fewer degenerating axons and more oligodendrocytes. T3 and Sob also protected cultured oligodendrocytes against cell death. Thyromimetics thus might protect against oligodendrocyte death, demyelination and axonal degeneration as well as stimulate remyelination in multiple sclerosis.
Collapse
Affiliation(s)
- P Chaudhary
- Department of Neurology, 3181 SW Sam Jackson Park Road, Portland, OR 97239, United States of America; VA Portland Health Care System, 3710 SW US Veterans Hospital Rd, Portland, OR 97239, United States of America.
| | - G H Marracci
- Department of Neurology, 3181 SW Sam Jackson Park Road, Portland, OR 97239, United States of America; VA Portland Health Care System, 3710 SW US Veterans Hospital Rd, Portland, OR 97239, United States of America
| | - E Calkins
- Department of Neurology, 3181 SW Sam Jackson Park Road, Portland, OR 97239, United States of America; VA Portland Health Care System, 3710 SW US Veterans Hospital Rd, Portland, OR 97239, United States of America
| | - E Pocius
- Department of Neurology, 3181 SW Sam Jackson Park Road, Portland, OR 97239, United States of America; VA Portland Health Care System, 3710 SW US Veterans Hospital Rd, Portland, OR 97239, United States of America
| | - A L Bensen
- Department of Neurology, 3181 SW Sam Jackson Park Road, Portland, OR 97239, United States of America; Jungers Center for Neurosciences Research, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, United States of America
| | - T S Scanlan
- Department of Chemical Physiology & Biochemistry and Program in Chemical Biology, 3181 SW Sam Jackson Park Road, Portland, OR 97239, United States of America
| | - B Emery
- Department of Neurology, 3181 SW Sam Jackson Park Road, Portland, OR 97239, United States of America; Jungers Center for Neurosciences Research, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, United States of America
| | - D N Bourdette
- Department of Neurology, 3181 SW Sam Jackson Park Road, Portland, OR 97239, United States of America; VA Portland Health Care System, 3710 SW US Veterans Hospital Rd, Portland, OR 97239, United States of America
| |
Collapse
|
7
|
van Geest FS, Groeneweg S, Visser WE. Monocarboxylate transporter 8 deficiency: update on clinical characteristics and treatment. Endocrine 2021; 71:689-695. [PMID: 33650046 PMCID: PMC8016746 DOI: 10.1007/s12020-020-02603-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 12/28/2020] [Indexed: 11/24/2022]
Abstract
Defective thyroid hormone transport due to deficiency in thyroid hormone transporter monocarboxylate transporter 8 (MCT8) results in severe neurodevelopmental delay due to cerebral hypothyroidism and in clinical negative sequelae following a chronic thyrotoxic state in peripheral tissues. The life expectancy of patients with MCT8 deficiency is severely impaired. Increased mortality is associated with lack of head control and being underweight at young age. Treatment options are available to alleviate the thyrotoxic state; particularly, treatment with the thyroid hormone analogue triiodothyroacetic acid seems a promising therapy. This review provides an overview of key clinical features and treatment options available and under development for this rare disorder.
Collapse
Affiliation(s)
- Ferdy S van Geest
- Academic Center For Thyroid Disease, Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Stefan Groeneweg
- Academic Center For Thyroid Disease, Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - W Edward Visser
- Academic Center For Thyroid Disease, Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands.
| |
Collapse
|
8
|
van Geest FS, Gunhanlar N, Groeneweg S, Visser WE. Monocarboxylate Transporter 8 Deficiency: From Pathophysiological Understanding to Therapy Development. Front Endocrinol (Lausanne) 2021; 12:723750. [PMID: 34539576 PMCID: PMC8440930 DOI: 10.3389/fendo.2021.723750] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 08/13/2021] [Indexed: 01/18/2023] Open
Abstract
Genetic defects in the thyroid hormone transporter monocarboxylate transporter 8 (MCT8) result in MCT8 deficiency. This disorder is characterized by a combination of severe intellectual and motor disability, caused by decreased cerebral thyroid hormone signalling, and a chronic thyrotoxic state in peripheral tissues, caused by exposure to elevated serum T3 concentrations. In particular, MCT8 plays a crucial role in the transport of thyroid hormone across the blood-brain-barrier. The life expectancy of patients with MCT8 deficiency is strongly impaired. Absence of head control and being underweight at a young age, which are considered proxies of the severity of the neurocognitive and peripheral phenotype, respectively, are associated with higher mortality rate. The thyroid hormone analogue triiodothyroacetic acid is able to effectively and safely ameliorate the peripheral thyrotoxicosis; its effect on the neurocognitive phenotype is currently under investigation. Other possible therapies are at a pre-clinical stage. This review provides an overview of the current understanding of the physiological role of MCT8 and the pathophysiology, key clinical characteristics and developing treatment options for MCT8 deficiency.
Collapse
|
9
|
Braun D, Schweizer U. The Protein Translocation Defect of MCT8 L291R Is Rescued by Sodium Phenylbutyrate. Eur Thyroid J 2020; 9:269-280. [PMID: 33088796 PMCID: PMC7548921 DOI: 10.1159/000507439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 03/24/2020] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION The monocarboxylate transporter 8 (MCT8; SLC16A2) is a specific transporter for thyroid hormones. MCT8 deficiency, formerly known as the Allan-Herndon-Dudley syndrome, is a rare genetic disease that leads to neurological impairments and muscle weakness. Current experimental treatment options rely on thyromimetic agonists that do not depend on MCT8 for cellular uptake. Another approach comes from studies with the chemical chaperone sodium phenylbutyrate (NaPB), which was able to stabilize MCT8 mutants having protein folding defects in vitro. In addition, NaPB is known as a compound that assists with plasma membrane translocation. OBJECTIVE The pathogenic MCT8L291R leads to the same severe neurological impairments found for other MCT8-deficient patients but, unexpectedly, lacks alterations in plasma 3,3',5-triiodothyronine (T3) levels. Here we tried to unravel the underlying mechanism of MCT8 deficiency and tested whether the pathogenic MCT8L291R mutant responds to NaPB treatment. Therefore, we overexpressed the mutant in Madin-Darby canine kidney cells in the human choriocarcinoma cell line JEG1 and in COS7 cells of African green monkey origin. RESULTS In our recent study we describe that the MCT8L291R mutation most likely leads to a translocation defect. The pathogenic mutant is not located at the plasma membrane, but shows overlapping expression with a marker protein of the lysosome. Mutation of the corresponding amino acid in murine Mct8 (Mct8L223R) displays a similar effect on cell surface expression and transport function as seen before for MCT8L291R. NaPB was able to correct the translocation defect of MCT8L291R/Mct8L223R and restored protein function by increasing T3 transport activity. Furthermore, we detected enhanced mRNA levels of wild-type and mutant MCT8/Mct8 after NaPB treatment. The increase in mRNA levels could be an explanation for the positive effect on protein expression and function detected for wild-type MCT8. CONCLUSION NaPB is not only suitable for the treatment of mutations leading to misfolding and protein degradation, but also for a mutant wrongly sorted inside a cell which is otherwise functional.
Collapse
Affiliation(s)
- Doreen Braun
- *Doreen Braun, Institut für Biochemie und Molekularbiologie, Medizinische Fakultät, Rheinische Friedrich-Wilhelms-Universität Bonn, Nussallee 11, DE–53115 Bonn (Germany),
| | | |
Collapse
|
10
|
Saponaro F, Sestito S, Runfola M, Rapposelli S, Chiellini G. Selective Thyroid Hormone Receptor-Beta (TRβ) Agonists: New Perspectives for the Treatment of Metabolic and Neurodegenerative Disorders. Front Med (Lausanne) 2020; 7:331. [PMID: 32733906 PMCID: PMC7363807 DOI: 10.3389/fmed.2020.00331] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 06/04/2020] [Indexed: 12/12/2022] Open
Abstract
Thyroid hormones (THs) elicit significant effects on numerous physiological processes, such as growth, development, and metabolism. A lack of thyroid hormones is not compatible with normal health. Most THs effects are mediated by two different thyroid hormone receptor (TR) isoforms, namely TRα and TRβ, with the TRβ isoform known to be responsible for the main beneficial effects of TH on liver. In brain, despite the crucial role of TRα isoform in neuronal development, TRβ has been proposed to play a role in the remyelination processes. Consequently, over the past two decades, much effort has been applied in developing thyroid hormone analogs capable of uncoupling beneficial actions on liver (triglyceride and cholesterol lowering) and central nervous system (CNS) (oligodendrocyte proliferation) from deleterious effects on the heart, muscle and bone. Sobetirome (GC-1) and subsequently Eprotirome (KB2115) were the first examples of TRβ selective thyromimetics, with Sobetirome differing from the structure of thyronines because of the absence of halogens, biaryl ether oxygen, and amino-acidic side chain. Even though both thyromimetics showed encouraging actions against hypercholesterolemia, non-alcoholic steatohepatitis (NASH) and in the stimulation of hepatocytes proliferation, they were stopped after Phase 1 and Phase 2–3 clinical trials, respectively. In recent years, advances in molecular and structural biology have facilitated the design of new selective thyroid hormone mimetics that exhibit TR isoform-selective binding, and/or liver- and tissue-selective uptake, with Resmetirom (MGL-3196) and Hep-Direct prodrug VK2809 (MB07811) probably representing two of the most promising lipid lowering agents, currently under phase 2–3 clinical trials. More recently the application of a comprehensive panel of ADME-Toxicity assays enabled the selection of novel thyromimetic IS25 and its prodrug TG68, as very powerful lipid lowering agents both in vitro and in vivo. In addition to dyslipidemia and other liver pathologies, THs analogs could also be of value for the treatment of neurodegenerative diseases, such as multiple sclerosis (MS). Sob-AM2, a CNS- selective prodrug of Sobetirome has been shown to promote significant myelin repair in the brain and spinal cord of mouse demyelinating models and it is rapidly moving into clinical trials in humans. Taken together all these findings support the great potential of selective thyromimetics in targeting a large variety of human pathologies characterized by altered metabolism and/or cellular differentiation.
Collapse
Affiliation(s)
| | - Simona Sestito
- Department of Pathology, University of Pisa, Pisa, Italy
| | | | - Simona Rapposelli
- Department of Pharmacy, University of Pisa, Pisa, Italy.,Interdepartmental Research Centre for Biology and Pathology of Aging, University of Pisa, Pisa, Italy
| | | |
Collapse
|
11
|
Grijota-Martínez C, Bárez-López S, Gómez-Andrés D, Guadaño-Ferraz A. MCT8 Deficiency: The Road to Therapies for a Rare Disease. Front Neurosci 2020; 14:380. [PMID: 32410949 PMCID: PMC7198743 DOI: 10.3389/fnins.2020.00380] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 03/27/2020] [Indexed: 12/17/2022] Open
Abstract
Allan-Herndon-Dudley syndrome is a rare disease caused by inactivating mutations in the SLC16A2 gene, which encodes the monocarboxylate transporter 8 (MCT8), a transmembrane transporter specific for thyroid hormones (T3 and T4). Lack of MCT8 function produces serious neurological disturbances, most likely due to impaired transport of thyroid hormones across brain barriers during development resulting in severe brain hypothyroidism. Patients also suffer from thyrotoxicity in other organs due to the presence of a high concentration of T3 in the serum. An effective therapeutic strategy should restore thyroid hormone serum levels (both T3 and T4) and should address MCT8 transporter deficiency in brain barriers and neural cells, to enable the access of thyroid hormones to target neural cells. Unfortunately, targeted therapeutic options are currently scarce and their effect is limited to an improvement in the thyrotoxic state, with no sign of any neurological improvement. The use of thyroid hormone analogs such as TRIAC, DITPA, or sobetirome, that do not require MCT8 to cross cell membranes and whose controlled thyromimetic activity could potentially restore the normal function of the affected organs, are being explored to improve the cerebral availability of these analogs. Other strategies aiming to restore the transport of THs through MCT8 at the brain barriers and the cellular membranes include gene replacement therapy and the use of pharmacological chaperones. The design of an appropriate therapeutic strategy in combination with an early diagnosis (at prenatal stages), will be key aspects to improve the devastating alterations present in these patients.
Collapse
Affiliation(s)
- Carmen Grijota-Martínez
- Department of Endocrine and Nervous System Pathophysiology, Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas (CSIC), Universidad Autónoma de Madrid (UAM), Madrid, Spain.,Center for Biomedical Research on Rare Diseases (Ciberer), Instituto de Salud Carlos III, Madrid, Spain.,Department of Cell Biology, Faculty of Biology, Universidad Complutense de Madrid, Madrid, Spain
| | - Soledad Bárez-López
- Center for Biomedical Research on Rare Diseases (Ciberer), Instituto de Salud Carlos III, Madrid, Spain.,Translational Health Sciences, Dorothy Hodgkin Building, University of Bristol, Bristol, United Kingdom
| | - David Gómez-Andrés
- Pediatric Neurology, Vall d'Hebron University Hospital and VHIR (Euro-NMD, ERN-RND), Barcelona, Spain
| | - Ana Guadaño-Ferraz
- Department of Endocrine and Nervous System Pathophysiology, Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas (CSIC), Universidad Autónoma de Madrid (UAM), Madrid, Spain.,Center for Biomedical Research on Rare Diseases (Ciberer), Instituto de Salud Carlos III, Madrid, Spain
| |
Collapse
|
12
|
Groeneweg S, van Geest FS, Peeters RP, Heuer H, Visser WE. Thyroid Hormone Transporters. Endocr Rev 2020; 41:5637505. [PMID: 31754699 DOI: 10.1210/endrev/bnz008] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 11/07/2019] [Indexed: 02/08/2023]
Abstract
Thyroid hormone transporters at the plasma membrane govern intracellular bioavailability of thyroid hormone. Monocarboxylate transporter (MCT) 8 and MCT10, organic anion transporting polypeptide (OATP) 1C1, and SLC17A4 are currently known as transporters displaying the highest specificity toward thyroid hormones. Structure-function studies using homology modeling and mutational screens have led to better understanding of the molecular basis of thyroid hormone transport. Mutations in MCT8 and in OATP1C1 have been associated with clinical disorders. Different animal models have provided insight into the functional role of thyroid hormone transporters, in particular MCT8. Different treatment strategies for MCT8 deficiency have been explored, of which thyroid hormone analogue therapy is currently applied in patients. Future studies may reveal the identity of as-yet-undiscovered thyroid hormone transporters. Complementary studies employing animal and human models will provide further insight into the role of transporters in health and disease. (Endocrine Reviews 41: 1 - 55, 2020).
Collapse
Affiliation(s)
- Stefan Groeneweg
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands Academic Center for Thyroid Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Ferdy S van Geest
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands Academic Center for Thyroid Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Robin P Peeters
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands Academic Center for Thyroid Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Heike Heuer
- Department of Endocrinology, Diabetes and Metabolism, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - W Edward Visser
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands Academic Center for Thyroid Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
| |
Collapse
|
13
|
Vancamp P, Demeneix BA, Remaud S. Monocarboxylate Transporter 8 Deficiency: Delayed or Permanent Hypomyelination? Front Endocrinol (Lausanne) 2020; 11:283. [PMID: 32477268 PMCID: PMC7237703 DOI: 10.3389/fendo.2020.00283] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 04/15/2020] [Indexed: 12/11/2022] Open
Abstract
Monocarboxylate transporter 8 (MCT8) deficiency or the Allan-Herndon-Dudley Syndrome (AHDS) is an X-linked psychomotor disability syndrome with around 320 clinical cases described worldwide. SLC16A2 gene mutations, encoding the thyroid hormone (TH) transporter MCT8, result in intellectual disability due to impaired TH uptake in the developing brain. MCT8 deficiency is a multi-organ affecting disease with a predominant neuronal cell-based pathology, with the glial component inadequately investigated. However, deficiency in myelin, a key component of white matter (WM) enabling fast nerve conduction, is a TH-dependent hallmark of the disease. Nevertheless, analysis of the myelin status in AHDS patients has led to conflicting interpretations. The majority of individual case studies reported delayed myelination, that was restored later in life. In contrast, post-mortem studies and high-resolution MRIs detected WM (micro-) abnormalities throughout adolescence, suggesting permanent hypomyelination. Thus, interpretations vary depending on methodology to investigate WM microstructure. Further, it is unknown whether the mutation within the MCT8 is linked to the severity of the myelin deficiency. Consequently, terminology is inconsistent among reports, and AHDS is occasionally misdiagnosed as another WM disorder. The evolutionary conserved TH signaling pathway that promotes the generation of myelinating oligodendrocytes enabled deciphering how the lack of MCT8 might affect myelinogenesis. Linking patient findings on myelination to those obtained from models of MCT8 deficiency revealed underlying pathophysiological mechanisms, but knowledge gaps remain, notably how myelination progresses both spatially and temporally in MCT8 deficiency. This limits predicting how myelin integrity might benefit therapeutically, and when to initiate. A recurrent observation in clinical trials is the absence of neurological improvement. Testing MCT8-independent thyromimetics in models, and evaluating treatments used in other demyelinating diseases, despite different etiologies, is crucial to propose new therapeutic strategies combatting this devastating disease.
Collapse
Affiliation(s)
- Pieter Vancamp
- UMR 7221 Molecular Physiology and Adaptation, Centre National de le Recherche Scientifique-Muséum National d'Histoire Naturelle, Paris, France
| | - Barbara A Demeneix
- UMR 7221 Molecular Physiology and Adaptation, Centre National de le Recherche Scientifique-Muséum National d'Histoire Naturelle, Paris, France
| | - Sylvie Remaud
- UMR 7221 Molecular Physiology and Adaptation, Centre National de le Recherche Scientifique-Muséum National d'Histoire Naturelle, Paris, France
| |
Collapse
|
14
|
Bárez-López S, Grijota-Martínez C, Ausó E, Fernández-de Frutos M, Montero-Pedrazuela A, Guadaño-Ferraz A. Adult Mice Lacking Mct8 and Dio2 Proteins Present Alterations in Peripheral Thyroid Hormone Levels and Severe Brain and Motor Skill Impairments. Thyroid 2019; 29:1669-1682. [PMID: 31359845 DOI: 10.1089/thy.2019.0068] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Background: Mutations in the thyroid hormone (TH) transporter monocarboxylate transporter 8 (MCT8) lead to peripheral hyperthyroidism and profound psychomotor alterations in humans. Mice lacking Mct8 present peripheral hyperthyroidism but no gross neurological abnormalities due to brain compensatory mechanisms involving the enzyme deiodinase type 2 (Dio2). Methods: Here we have analyzed the endocrine and neurologic phenotype of mice lacking both Mct8 and Dio2 at three and six months of age. Thyroxine (T4) and 3,5,3' triiodothyronine (T3) levels/content were measured by specific radioimmunoassays; motor skill performance was evaluated by the footprint, rotarod, four limb hanging wire, and balance beam tests; and brain histological analysis was performed by immunostaining for neurofilament and parvalbumin. Results: We have found that this mouse model presents peripheral hyperthyroidism and brain hypothyroidism. Interestingly, the severity of the brain hypothyroidism seems permanent and varies across regions, with the striatum being a particularly affected area. We have also found brain alterations at the histological level compatible with TH deficiency and impaired motor skills. Conclusions: These findings indicate the potential of Mct8/Dio2-deficient mice to represent a model for human MCT8 deficiency, to understand the mechanisms underlying its pathophysiology, and ultimately design therapeutic interventions for human patients.
Collapse
Affiliation(s)
- Soledad Bárez-López
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Unit 708, Center for Biomedical Research On Rare Diseases (Ciberer), Instituto de Salud Carlos III, Madrid, Spain
| | - Carmen Grijota-Martínez
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Unit 708, Center for Biomedical Research On Rare Diseases (Ciberer), Instituto de Salud Carlos III, Madrid, Spain
| | - Eva Ausó
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante, Alicante, Spain
| | - Mario Fernández-de Frutos
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - Ana Montero-Pedrazuela
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - Ana Guadaño-Ferraz
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Unit 708, Center for Biomedical Research On Rare Diseases (Ciberer), Instituto de Salud Carlos III, Madrid, Spain
| |
Collapse
|
15
|
Hartley MD, Banerji T, Tagge IJ, Kirkemo LL, Chaudhary P, Calkins E, Galipeau D, Shokat MD, DeBell MJ, Van Leuven S, Miller H, Marracci G, Pocius E, Banerji T, Ferrara SJ, Meinig JM, Emery B, Bourdette D, Scanlan TS. Myelin repair stimulated by CNS-selective thyroid hormone action. JCI Insight 2019; 4:126329. [PMID: 30996143 PMCID: PMC6538346 DOI: 10.1172/jci.insight.126329] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 03/12/2019] [Indexed: 12/21/2022] Open
Abstract
Oligodendrocyte processes wrap axons to form neuroprotective myelin sheaths, and damage to myelin in disorders, such as multiple sclerosis (MS), leads to neurodegeneration and disability. There are currently no approved treatments for MS that stimulate myelin repair. During development, thyroid hormone (TH) promotes myelination through enhancing oligodendrocyte differentiation; however, TH itself is unsuitable as a remyelination therapy due to adverse systemic effects. This problem is overcome with selective TH agonists, sobetirome and a CNS-selective prodrug of sobetirome called Sob-AM2. We show here that TH and sobetirome stimulated remyelination in standard gliotoxin models of demyelination. We then utilized a genetic mouse model of demyelination and remyelination, in which we employed motor function tests, histology, and MRI to demonstrate that chronic treatment with sobetirome or Sob-AM2 leads to significant improvement in both clinical signs and remyelination. In contrast, chronic treatment with TH in this model inhibited the endogenous myelin repair and exacerbated disease. These results support the clinical investigation of selective CNS-penetrating TH agonists, but not TH, for myelin repair.
Collapse
Affiliation(s)
- Meredith D. Hartley
- Department of Physiology & Pharmacology and Program in Chemical Biology, Oregon Health & Science University, Portland, Oregon, USA
- VA Portland Health Care System, Portland, Oregon, USA
| | - Tania Banerji
- Department of Physiology & Pharmacology and Program in Chemical Biology, Oregon Health & Science University, Portland, Oregon, USA
| | | | - Lisa L. Kirkemo
- Department of Physiology & Pharmacology and Program in Chemical Biology, Oregon Health & Science University, Portland, Oregon, USA
- VA Portland Health Care System, Portland, Oregon, USA
| | - Priya Chaudhary
- VA Portland Health Care System, Portland, Oregon, USA
- Department of Neurology, and
| | - Evan Calkins
- VA Portland Health Care System, Portland, Oregon, USA
- Department of Neurology, and
| | - Danielle Galipeau
- VA Portland Health Care System, Portland, Oregon, USA
- Department of Neurology, and
| | - Mitra D. Shokat
- Department of Physiology & Pharmacology and Program in Chemical Biology, Oregon Health & Science University, Portland, Oregon, USA
| | - Margaret J. DeBell
- Department of Physiology & Pharmacology and Program in Chemical Biology, Oregon Health & Science University, Portland, Oregon, USA
| | - Shelby Van Leuven
- Department of Physiology & Pharmacology and Program in Chemical Biology, Oregon Health & Science University, Portland, Oregon, USA
| | - Hannah Miller
- Department of Physiology & Pharmacology and Program in Chemical Biology, Oregon Health & Science University, Portland, Oregon, USA
| | - Gail Marracci
- VA Portland Health Care System, Portland, Oregon, USA
- Department of Neurology, and
| | - Edvinas Pocius
- VA Portland Health Care System, Portland, Oregon, USA
- Department of Neurology, and
| | - Tapasree Banerji
- Department of Physiology & Pharmacology and Program in Chemical Biology, Oregon Health & Science University, Portland, Oregon, USA
| | - Skylar J. Ferrara
- Department of Physiology & Pharmacology and Program in Chemical Biology, Oregon Health & Science University, Portland, Oregon, USA
| | - J. Matthew Meinig
- Department of Physiology & Pharmacology and Program in Chemical Biology, Oregon Health & Science University, Portland, Oregon, USA
| | - Ben Emery
- Department of Neurology, and
- Jungers Center for Neurosciences Research, Oregon Health & Science University, Portland, Oregon, USA
| | - Dennis Bourdette
- VA Portland Health Care System, Portland, Oregon, USA
- Department of Neurology, and
| | - Thomas S. Scanlan
- Department of Physiology & Pharmacology and Program in Chemical Biology, Oregon Health & Science University, Portland, Oregon, USA
| |
Collapse
|
16
|
Meinig JM, Ferrara SJ, Banerji T, Banerji T, Sanford-Crane HS, Bourdette D, Scanlan TS. Structure-Activity Relationships of Central Nervous System Penetration by Fatty Acid Amide Hydrolase (FAAH)-Targeted Thyromimetic Prodrugs. ACS Med Chem Lett 2019; 10:111-116. [PMID: 30655956 DOI: 10.1021/acsmedchemlett.8b00501] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 12/04/2018] [Indexed: 02/06/2023] Open
Abstract
Thyroid hormone (TH) action is of clinical interest in treating demyelinating diseases of the central nervous system (CNS). Two amide prodrugs of sobetirome, a potent thyroid hormone agonist, were previously shown to significantly improve CNS selective distribution of the parent drug through hydrolysis in the CNS by fatty acid amide hydrolase (FAAH). This concept is elaborated upon here with a series of 29 amide prodrugs targeting FAAH. We identify that conservative aliphatic modifications such as the N-methyl (4), N-ethyl (5), N-fluoroethyl (15), and N-cyclopropyl (18) substantially favor selective CNS distribution of the parent drug in mice. Additionally, lead compounds exhibit moderate to good rates of hydrolysis at FAAH in vitro suggesting both enzymatic and physicochemical properties are important parameters for optimization. Both 4 and 15 were orally bioavailable while retaining appreciable CNS parent drug delivery following an oral dose. The pharmacokinetic parameters of 4 over 24 h postdose (i.v. and p.o.) were determined.
Collapse
|
17
|
Ferrara SJ, Bourdette D, Scanlan TS. Hypothalamic-Pituitary-Thyroid Axis Perturbations in Male Mice by CNS-Penetrating Thyromimetics. Endocrinology 2018; 159:2733-2740. [PMID: 29846550 PMCID: PMC6457038 DOI: 10.1210/en.2018-00065] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 05/22/2018] [Indexed: 02/08/2023]
Abstract
Thyromimetics represent a class of experimental drugs that can stimulate tissue-selective thyroid hormone action. As such, thyromimetics should have effects on the hypothalamic-pituitary-thyroid (HPT) axis, but details of this action and the subsequent effects on systemic thyroid hormone levels have not been reported to date. Here, we compare the HPT-axis effects of sobetirome, a well-studied thyromimetic, with Sob-AM2, a newly developed prodrug of sobetirome that targets sobetirome distribution to the central nervous system (CNS). Similar to endogenous thyroid hormone, administration of sobetirome and Sob-AM2 suppress HPT-axis gene transcript levels in a manner that correlates to their specific tissue distribution properties (periphery vs CNS, respectively). Dosing male C57BL/6 mice with sobetirome and Sob-AM2 at concentrations ≥10 μg/kg/d for 29 days induces a state similar to central hypothyroidism characterized by depleted circulating T4 and T3 and normal TSH levels. However, despite the systemic T4 and T3 depletion, the sobetirome- and Sob-AM2-treated mice do not show signs of hypothyroidism, which may result from the presence of the thyromimetic in the thyroid hormone-depleted background.
Collapse
Affiliation(s)
- Skylar J Ferrara
- Program in Chemical Biology, Department of Physiology & Pharmacology, Oregon Health and Science University, Portland, Oregon
| | - Dennis Bourdette
- Department of Neurology, Oregon Health and Science University, Portland, Oregon
| | - Thomas S Scanlan
- Program in Chemical Biology, Department of Physiology & Pharmacology, Oregon Health and Science University, Portland, Oregon
- Correspondence: Thomas S. Scanlan, PhD, Department of Physiology and Pharmacology, Program in Chemical Biology, Oregon Health and Science University, 3181 Southwest Sam Jackson Road, L334, Portland, Oregon 97206. E-mail:
| |
Collapse
|