1
|
Maddox SA, Ponomareva OY, Zaleski CE, Chen MX, Vella KR, Hollenberg AN, Klengel C, Ressler KJ. Evidence for thyroid hormone regulation of amygdala-dependent fear-relevant memory and plasticity. Mol Psychiatry 2024:10.1038/s41380-024-02679-2. [PMID: 39039155 DOI: 10.1038/s41380-024-02679-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 07/08/2024] [Accepted: 07/16/2024] [Indexed: 07/24/2024]
Abstract
The amygdala is an established site for fear memory formation, and clinical studies suggest involvement of hormone signaling cascades in development of trauma-related disorders. While an association of thyroid hormone (TH) status and mood disorders is established, the related brain-based mechanisms and the role of TH in anxiety disorders are unknown. Here we examine the role that TH receptor (TR, a nuclear transcriptional repressor when unbound and a transcriptional activator when bound to TH) may have in mediating the initial formation of fear memories in the amygdala. We identified mRNA levels of TR and other TH pathway regulatory genes, including thyrotropin-releasing hormone (Trh), transthyretin (Ttr), thyrotropin-releasing hormone receptor (Trhr), type 2 iodothyronine deiodinase (Dio2), mediator complex subunit 12 (Med12/Trap230) and retinoid X receptor gamma (Rxrg) to be altered in the amygdala following Pavlovian fear conditioning. Using TH agonist and antagonist infusion into the amygdala, we demonstrated that this pathway is both necessary and sufficient for fear memory consolidation. Inhibition of TH signaling with the TR antagonist 1-850 decreased fear memory consolidation; while activation of TR with T3 (triiodothyronine) resulted in increased memory formation. Using a systemic hypothyroid mouse model, we found that intra-amygdala infusions of T3 were sufficient to rescue deficits in fear memory. Finally, we demonstrated that T3 was sufficient to activate TR-specific gene pathways in the amygdala. These findings on the role of activity-dependent TR modulation support a model in which local TH is a critical regulator of fear memory-related plasticity in the amygdala.
Collapse
Affiliation(s)
- Stephanie A Maddox
- Neurobiology of Fear Laboratory, Basic Neuroscience Division, McLean Hospital, Belmont, MA, USA
- Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Olga Y Ponomareva
- Neurobiology of Fear Laboratory, Basic Neuroscience Division, McLean Hospital, Belmont, MA, USA
- Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Cole E Zaleski
- Neurobiology of Fear Laboratory, Basic Neuroscience Division, McLean Hospital, Belmont, MA, USA
- Northeastern University, Boston, MA, USA
| | - Michelle X Chen
- Neurobiology of Fear Laboratory, Basic Neuroscience Division, McLean Hospital, Belmont, MA, USA
- University of Iowa, Iowa City, IA, USA
| | - Kristen R Vella
- Joan and Sanford I. Weill Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Weill Cornell Medicine, New York, NY, USA
- Weill Center for Metabolic Health, Weill Cornell Medicine, New York, NY, USA
| | - Anthony N Hollenberg
- Joan and Sanford I. Weill Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Weill Cornell Medicine, New York, NY, USA
- Weill Center for Metabolic Health, Weill Cornell Medicine, New York, NY, USA
| | - Claudia Klengel
- Neurobiology of Fear Laboratory, Basic Neuroscience Division, McLean Hospital, Belmont, MA, USA
| | - Kerry J Ressler
- Neurobiology of Fear Laboratory, Basic Neuroscience Division, McLean Hospital, Belmont, MA, USA.
- Department of Psychiatry, Harvard Medical School, Boston, MA, USA.
| |
Collapse
|
2
|
Wagenaars F, Cenijn P, Chen Z, Meima M, Scholze M, Hamers T. Two novel in vitro assays to screen chemicals for their capacity to inhibit thyroid hormone transmembrane transporter proteins OATP1C1 and OAT4. Arch Toxicol 2024:10.1007/s00204-024-03787-2. [PMID: 38761188 DOI: 10.1007/s00204-024-03787-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Accepted: 05/08/2024] [Indexed: 05/20/2024]
Abstract
Early brain development depends on adequate transport of thyroid hormones (THs) from the maternal circulation to the fetus. To reach the fetal brain, THs have to cross several physiological barriers, including the placenta, blood-brain-barrier and blood-cerebrospinal fluid-barrier. Transport across these barriers is facilitated by thyroid hormone transmembrane transporters (THTMTs). Some endocrine disrupting chemicals (EDCs) can interfere with the transport of THs by THTMTs. To screen chemicals for their capacity to disrupt THTMT facilitated TH transport, in vitro screening assays are required. In this study, we developed assays for two THTMTs, organic anion transporter polypeptide 1C1 (OATP1C1) and organic anion transporter 4 (OAT4), both known to play a role in the transport of THs across barriers. We used overexpressing cell models for both OATP1C1 and OAT4, which showed an increased uptake of radiolabeled T4 compared to control cell lines. Using these models, we screened various reference and environmental chemicals for their ability to inhibit T4 uptake by OATP1C1 and OAT4. Tetrabromobisphenol A (TBBPA) was identified as an OATP1C1 inhibitor, more potent than any of the reference chemicals tested. Additionally perfluorooctanesulfonic acid (PFOS), perfluoroctanic acid (PFOA), pentachlorophenol and quercetin were identified as OATP1C1 inhibitors in a similar range of potency to the reference chemicals tested. Bromosulfophthalein, TBBPA, PFOA and PFOS were identified as potent OAT4 inhibitors. These results demonstrate that EDCs commonly found in our environment can disrupt TH transport by THTMTs, and contribute to the identification of molecular mechanisms underlying TH system disruption chemicals.
Collapse
Affiliation(s)
- Fabian Wagenaars
- Amsterdam Institute for Life and Environment (A-Life), Vrije Universiteit Amsterdam (VU), De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands.
| | - Peter Cenijn
- Amsterdam Institute for Life and Environment (A-Life), Vrije Universiteit Amsterdam (VU), De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands
| | - Zhongli Chen
- Academic Centre for Thyroid Diseases, Department of Internal Medicine, Erasmus University Medical Center Rotterdam, 3015 GD, Rotterdam, The Netherlands
| | - Marcel Meima
- Academic Centre for Thyroid Diseases, Department of Internal Medicine, Erasmus University Medical Center Rotterdam, 3015 GD, Rotterdam, The Netherlands
| | - Martin Scholze
- Centre for Pollution Research and Policy, College of Health, Medicine and Life Sciences, Brunel University London, Kingston Lane, Uxbridge, UB8 3PH, UK
| | - Timo Hamers
- Amsterdam Institute for Life and Environment (A-Life), Vrije Universiteit Amsterdam (VU), De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands
| |
Collapse
|
3
|
Sun A, Hagenbuch B, Kelly EJ, Wang J. Molecular Mechanisms of Organic Anion Transporting Polypeptide-Mediated Organic Anion Clearance at the Blood-Cerebrospinal Fluid Barrier. Mol Pharmacol 2023; 104:255-265. [PMID: 37652713 PMCID: PMC10658916 DOI: 10.1124/molpharm.123.000703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 08/07/2023] [Accepted: 08/14/2023] [Indexed: 09/02/2023] Open
Abstract
The blood-cerebrospinal fluid barrier (BCSFB), formed by the choroid plexus epithelial (CPE) cells, plays an active role in removing drugs and metabolic wastes from the brain. Recent functional studies in isolated mouse choroid plexus (CP) tissues suggested the presence of organic anion transporting polypeptides (OATPs, encoded by SLCOs) at the apical membrane of BCSFB, which may clear large organic anions from the cerebrospinal fluid (CSF). However, the specific OATP isoform involved is unclear. Using quantitative fluorescence imaging, we showed that the fluorescent anions sulforhodamine 101 (SR101), fluorescein methotrexate (FL-MTX), and 8-fluorescein-cAMP (fluo-cAMP) are actively transported from the CSF to the subepithelial space in CP tissues isolated from wild-type mice. In contrast, transepithelial transport of these compounds across the CPE cells was abolished in Oatp1a/1b-/- mice due to impaired apical uptake. Using transporter-expressing cell lines, SR101, FL-MTX, and fluo-cAMP were additionally shown to be transported by mouse OATP1A5 and its human counterpart OATP1A2. Kinetic analysis showed that estrone-3-sulfate and SR101 are transported by OATP1A2 and OATP1A5 with similar Michaelis-Menten constants (Km). Immunofluorescence staining further revealed the presence of OATP1A2 protein in human CP tissues. Together, our results suggest that large organic anions in the CSF are actively transported into CPE cells by apical OATP1A2 (OATP1A5 in mice), then subsequently effluxed into the blood by basolateral multidrug resistance-associated proteins (MRPs). As OATP1A2 transports a wide array of endogenous compounds and xenobiotics, the presence of this transporter at the BCSFB may imply a novel clearance route for drugs and neurohormones from the CSF. SIGNIFICANCE STATEMENT: Drug transporters at the blood-cerebrospinal fluid (CSF) barrier play an important but understudied role in brain drug disposition. This study revealed a functional contribution of rodent organic anion transporting polypeptide (OATP) 1A5 towards the CSF clearance of organic anions and suggested a similar role for OATP1A2 in humans. Delineating the molecular mechanisms governing CSF organic anion clearance may help to improve the prediction of central nervous system (CNS) pharmacokinetics and identify drug candidates with favorable CNS pharmacokinetic properties.
Collapse
Affiliation(s)
- Austin Sun
- Department of Pharmaceutics (A.S., E.J.K., J.W.) and Kidney Research Institute (E.J.K.), University of Washington, Seattle, Washington; and Department of Pharmacology, Toxicology, and Therapeutics, The University of Kansas Medical Center, Kansas City, Kansas (B.H.)
| | - Bruno Hagenbuch
- Department of Pharmaceutics (A.S., E.J.K., J.W.) and Kidney Research Institute (E.J.K.), University of Washington, Seattle, Washington; and Department of Pharmacology, Toxicology, and Therapeutics, The University of Kansas Medical Center, Kansas City, Kansas (B.H.)
| | - Edward J Kelly
- Department of Pharmaceutics (A.S., E.J.K., J.W.) and Kidney Research Institute (E.J.K.), University of Washington, Seattle, Washington; and Department of Pharmacology, Toxicology, and Therapeutics, The University of Kansas Medical Center, Kansas City, Kansas (B.H.)
| | - Joanne Wang
- Department of Pharmaceutics (A.S., E.J.K., J.W.) and Kidney Research Institute (E.J.K.), University of Washington, Seattle, Washington; and Department of Pharmacology, Toxicology, and Therapeutics, The University of Kansas Medical Center, Kansas City, Kansas (B.H.)
| |
Collapse
|
4
|
Li W, Iusuf D, Sparidans RW, Wagenaar E, Wang Y, de Waart DR, Martins MLF, van Hoppe S, Lebre MC, van Tellingen O, Beijnen JH, Schinkel AH. Organic anion-transporting polypeptide 2B1 knockout and humanized mice; insights into the handling of bilirubin and drugs. Pharmacol Res 2023; 190:106724. [PMID: 36907287 DOI: 10.1016/j.phrs.2023.106724] [Citation(s) in RCA: 3] [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: 01/17/2023] [Revised: 02/25/2023] [Accepted: 03/09/2023] [Indexed: 03/12/2023]
Abstract
Organic anion transporting polypeptide 2B1 (OATP2B1/SLCO2B1) facilitates uptake transport of structurally diverse endogenous and exogenous compounds. To investigate the roles of OATP2B1 in physiology and pharmacology, we established and characterized Oatp2b1 knockout (single Slco2b1-/- and combination Slco1a/1b/2b1-/-) and humanized hepatic and intestinal OATP2B1 transgenic mouse models. While viable and fertile, these strains exhibited a modestly increased body weight. In males, unconjugated bilirubin levels were markedly reduced in Slco2b1-/- compared to wild-type mice, whereas bilirubin monoglucuronide levels were modestly increased in Slco1a/1b/2b1-/- compared to Slco1a/1b-/- mice. Single Slco2b1-/- mice showed no significant changes in oral pharmacokinetics of several tested drugs. However, markedly higher or lower plasma exposure of pravastatin and the erlotinib metabolite OSI-420, respectively, were found in Slco1a/1b/2b1-/- compared to Slco1a/1b-/- mice, while oral rosuvastatin and fluvastatin behaved similarly between the strains. In males, humanized OATP2B1 strains showed lower conjugated and unconjugated bilirubin levels than control Slco1a/1b/2b1-deficient mice. Moreover, hepatic expression of human OATP2B1 partially or completely rescued the impaired hepatic uptake of OSI-420, rosuvastatin, pravastatin, and fluvastatin in Slco1a/1b/2b1-/- mice, establishing an important role in hepatic uptake. Expression of human OATP2B1 in the intestine was basolateral and markedly reduced the oral availability of rosuvastatin and pravastatin, but not of OSI-420 and fluvastatin. Neither lack of Oatp2b1, nor overexpression of human OATP2B1 had any effect on fexofenadine oral pharmacokinetics. While these mouse models still have limitations for human translation, with additional work we expect they will provide powerful tools to further understand the physiological and pharmacological roles of OATP2B1.
Collapse
Affiliation(s)
- Wenlong Li
- The Netherlands Cancer Institute, Division of Pharmacology, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands
| | - Dilek Iusuf
- The Netherlands Cancer Institute, Division of Pharmacology, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands
| | - Rolf W Sparidans
- Utrecht University, Faculty of Science, Department of Pharmaceutical Sciences, Division of Pharmacology, Universiteitsweg 99, 3584 CG, Utrecht, the Netherlands
| | - Els Wagenaar
- The Netherlands Cancer Institute, Division of Pharmacology, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands
| | - Yaogeng Wang
- The Netherlands Cancer Institute, Division of Pharmacology, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands
| | - Dirk R de Waart
- Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Meibergdreef 71, 1105 BK, Amsterdam, the Netherlands
| | - Margarida L F Martins
- The Netherlands Cancer Institute, Division of Pharmacology, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands
| | - Stéphanie van Hoppe
- The Netherlands Cancer Institute, Division of Pharmacology, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands
| | - Maria C Lebre
- The Netherlands Cancer Institute, Division of Pharmacology, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands
| | - Olaf van Tellingen
- The Netherlands Cancer Institute, Division of Pharmacology, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands
| | - Jos H Beijnen
- The Netherlands Cancer Institute, Division of Pharmacology, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands; Utrecht University, Faculty of Science, Department of Pharmaceutical Sciences, Division of Pharmacoepidemiology & Clinical Pharmacology, Universiteitsweg 99, 3584 CG Utrecht, the Netherlands; The Netherlands Cancer Institute, Department of Pharmacy & Pharmacology, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands
| | - Alfred H Schinkel
- The Netherlands Cancer Institute, Division of Pharmacology, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands.
| |
Collapse
|
5
|
Drake SS, Zaman A, Simas T, Fournier AE. Comparing RNA-sequencing datasets from astrocytes, oligodendrocytes, and microglia in multiple sclerosis identifies novel dysregulated genes relevant to inflammation and myelination. WIREs Mech Dis 2023; 15:e1594. [PMID: 36600404 DOI: 10.1002/wsbm.1594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 09/25/2022] [Accepted: 12/14/2022] [Indexed: 01/06/2023]
Abstract
Central nervous system (CNS) inflammation is a key factor in multiple sclerosis (MS). Invasion of peripheral immune cells into the CNS resulting from an unknown signal or combination of signals results in activation of resident immune cells and the hallmark feature of the disease: demyelinating lesions. These lesion sites are an amalgam of reactive peripheral and central immune cells, astrocytes, damaged and dying oligodendrocytes, and injured neurons and axons. Sustained inflammation affects cells directly located within the lesion site and further abnormalities are apparent diffusely throughout normal-appearing white matter and grey matter. It is only relatively recently, using animal models, new tissue sampling techniques, and next-generation sequencing, that molecular changes occurring in CNS resident cells have been broadly captured. Advances in cell isolation through Fluorescence Activated Cell Sorting (FACS) and laser-capture microdissection together with the emergence of single-cell sequencing have enabled researchers to investigate changes in gene expression in astrocytes, microglia, and oligodendrocytes derived from animal models of MS as well as from primary patient tissue. The contribution of some dysregulated pathways has been followed up in individual studies; however, corroborating results often go unreported between sequencing studies. To this end, we have consolidated results from numerous RNA-sequencing studies to identify and review novel patterns of differentially regulated genes and pathways occurring within CNS glial cells in MS. This article is categorized under: Neurological Diseases > Molecular and Cellular Physiology.
Collapse
Affiliation(s)
- Sienna S Drake
- McGill University, Montreal Neurological Institute, Montreal, Quebec, Canada
| | - Aliyah Zaman
- McGill University, Montreal Neurological Institute, Montreal, Quebec, Canada
| | - Tristan Simas
- McGill University, Montreal Neurological Institute, Montreal, Quebec, Canada
| | - Alyson E Fournier
- McGill University, Montreal Neurological Institute, Montreal, Quebec, Canada
| |
Collapse
|
6
|
Thyroid Hormone Transporters MCT8 and OATP1C1 Are Expressed in Pyramidal Neurons and Interneurons in the Adult Motor Cortex of Human and Macaque Brain. Int J Mol Sci 2023; 24:ijms24043207. [PMID: 36834621 PMCID: PMC9965431 DOI: 10.3390/ijms24043207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/26/2023] [Accepted: 02/01/2023] [Indexed: 02/09/2023] Open
Abstract
Monocarboxylate transporter 8 (MCT8) and organic anion transporter polypeptide 1C1 (OATP1C1) are thyroid hormone (TH) transmembrane transporters that play an important role in the availability of TH for neural cells, allowing their proper development and function. It is important to define which cortical cellular subpopulations express those transporters to explain why MCT8 and OATP1C1 deficiency in humans leads to dramatic alterations in the motor system. By means of immunohistochemistry and double/multiple labeling immunofluorescence in adult human and monkey motor cortices, we demonstrate the presence of both transporters in long-projection pyramidal neurons and in several types of short-projection GABAergic interneurons in both species, suggesting a critical position of these transporters for modulating the efferent motor system. MCT8 is present at the neurovascular unit, but OATP1C1 is only present in some of the large vessels. Both transporters are expressed in astrocytes. OATP1C1 was unexpectedly found, only in the human motor cortex, inside the Corpora amylacea complexes, aggregates linked to substance evacuation towards the subpial system. On the basis of our findings, we propose an etiopathogenic model that emphasizes these transporters' role in controlling excitatory/inhibitory motor cortex circuits in order to understand some of the severe motor disturbances observed in TH transporter deficiency syndromes.
Collapse
|
7
|
Thyroid Hormone Transporters in Pregnancy and Fetal Development. Int J Mol Sci 2022; 23:ijms232315113. [PMID: 36499435 PMCID: PMC9737226 DOI: 10.3390/ijms232315113] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 11/25/2022] [Accepted: 11/26/2022] [Indexed: 12/05/2022] Open
Abstract
Thyroid hormone is essential for fetal (brain) development. Plasma membrane transporters control the intracellular bioavailability of thyroid hormone. In the past few decades, 15 human thyroid hormone transporters have been identified, and among them, mutations in monocarboxylate transporter (MCT)8 and organic anion transporting peptide (OATP)1C1 are associated with clinical phenotypes. Different animal and human models have been employed to unravel the (patho)-physiological role of thyroid hormone transporters. However, most studies on thyroid hormone transporters focus on postnatal development. This review summarizes the research on the thyroid hormone transporters in pregnancy and fetal development, including their substrate preference, expression and tissue distribution, and physiological and pathophysiological role in thyroid homeostasis and clinical disorders. As the fetus depends on the maternal thyroid hormone supply, especially during the first half of pregnancy, the review also elaborates on thyroid hormone transport across the human placental barrier. Future studies may reveal how the different transporters contribute to thyroid hormone homeostasis in fetal tissues to properly facilitate development. Employing state-of-the-art human models will enable a better understanding of their roles in thyroid hormone homeostasis.
Collapse
|
8
|
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
|
9
|
Taggi V, Riera Romo M, Piquette-Miller M, Meyer zu Schwabedissen HE, Neuhoff S. Transporter Regulation in Critical Protective Barriers: Focus on Brain and Placenta. Pharmaceutics 2022; 14:pharmaceutics14071376. [PMID: 35890272 PMCID: PMC9319476 DOI: 10.3390/pharmaceutics14071376] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/14/2022] [Accepted: 06/24/2022] [Indexed: 01/06/2023] Open
Abstract
Drug transporters play an important role in the maintenance of chemical balance and homeostasis in different tissues. In addition to their physiological functions, they are crucial for the absorption, distribution, and elimination of many clinically important drugs, thereby impacting therapeutic efficacy and toxicity. Increasing evidence has demonstrated that infectious, metabolic, inflammatory, and neurodegenerative diseases alter the expression and function of drug transporters. However, the current knowledge on transporter regulation in critical protective barriers, such as the brain and placenta, is still limited and requires more research. For instance, while many studies have examined P-glycoprotein, it is evident that research on the regulation of highly expressed transporters in the blood–brain barrier and blood–placental barrier are lacking. The aim of this review is to summarize the currently available literature in order to better understand transporter regulation in these critical barriers.
Collapse
Affiliation(s)
- Valerio Taggi
- Biopharmacy, Department of Pharmaceutical Sciences, University of Basel, 4056 Basel, Switzerland; (V.T.); (H.E.M.z.S.)
| | - Mario Riera Romo
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON M5S 3M2, Canada; (M.R.R.); (M.P.-M.)
| | - Micheline Piquette-Miller
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON M5S 3M2, Canada; (M.R.R.); (M.P.-M.)
| | | | - Sibylle Neuhoff
- Certara UK Ltd., Simcyp Division, Sheffield S1 2BJ, UK
- Correspondence:
| |
Collapse
|
10
|
Mayerl S, Alcaide Martin A, Bauer R, Schwaninger M, Heuer H, ffrench-Constant C. Distinct Actions of the Thyroid Hormone Transporters Mct8 and Oatp1c1 in Murine Adult Hippocampal Neurogenesis. Cells 2022; 11:524. [PMID: 35159334 PMCID: PMC8834272 DOI: 10.3390/cells11030524] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 01/25/2022] [Accepted: 01/26/2022] [Indexed: 11/17/2022] Open
Abstract
Inactivating mutations in the thyroid hormone (TH) transporter monocarboxylate transporter 8 (MCT8) result in Allan-Herndon-Dudley Syndrome, a severe form of psychomotor retardation, while inactivating mutations in another TH transporter, organic anion transporting polypeptide 1c1 (OATP1C1), are linked to juvenile neurodegeneration. These diseases point to essential roles for TH transporters in CNS function. We recently defined the presence of Mct8 in adult hippocampal progenitors and mature granule cell neurons and unraveled cell-autonomous and indirect requirements for Mct8 in adult hippocampal neurogenesis. Here, we investigated whether Oatp1c1 is involved in the hippocampal neurogenic process in concert with Mct8. We detected Oatp1c1 gene expression activity and transcripts in subsets of progenitors, neurons and niche cells in the dentate gyrus. Absence of Oatp1c1 resulted in increased neuroblast and reduced immature neuron numbers in 6-month-old Oatp1c1ko and Mct8/Oatp1c1 double knockout (M/Odko) mice. Reduced EdU-label retention in Mct8ko and M/Odko mice confirmed the impact of Mct8 on neuron formation. In contrast, no significant effect of Oatp1c1 loss on granule cell neuron production and anxiety-like behavior in the open field arena were seen. Together, our results reinforce that distinct actions of each TH transporter are required at multiple stages to ensure proper adult hippocampal neurogenesis.
Collapse
Affiliation(s)
- Steffen Mayerl
- Department of Endocrinology, Diabetes & Metabolism, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (A.A.M.); (H.H.)
- MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH16 4UU, UK;
| | - Andrea Alcaide Martin
- Department of Endocrinology, Diabetes & Metabolism, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (A.A.M.); (H.H.)
| | - Reinhard Bauer
- Institute of Molecular Cell Biology, Jena University Hospital, 07745 Jena, Germany;
| | - Markus Schwaninger
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, 23562 Lübeck, Germany;
| | - Heike Heuer
- Department of Endocrinology, Diabetes & Metabolism, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (A.A.M.); (H.H.)
| | - Charles ffrench-Constant
- MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH16 4UU, UK;
- Faculty of Medicine and Health Sciences, University of East Anglia, Norwich NR4 7TJ, UK
| |
Collapse
|
11
|
Brain Perivascular Macrophages Do Not Mediate Interleukin-1-Induced Sickness Behavior in Rats. Pharmaceuticals (Basel) 2021; 14:ph14101030. [PMID: 34681254 PMCID: PMC8541198 DOI: 10.3390/ph14101030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 10/01/2021] [Accepted: 10/07/2021] [Indexed: 01/08/2023] Open
Abstract
Sickness behavior, characterized by on overall reduction in behavioral activity, is commonly observed after bacterial infection. Sickness behavior can also be induced by the peripheral administration of Gram-negative bacterial lipopolysaccharide (LPS) or interleukin-1beta (IL-1β), a pro-inflammatory cytokine released by LPS-activated macrophages. In addition to the microglia, the brain contains perivascular macrophages, which express the IL-1 type 1 receptor (IL-1R1). In the present study, we assessed the role of brain perivascular macrophages in mediating IL-1β-induced sickness behavior in rats. To do so, we used intracerebroventricular (icv) administration of an IL-1β-saporin conjugate, known to eliminate IL-R1-expressing brain cells, prior to systemic or central IL-1β injection. Icv IL-1β-saporin administration resulted in a reduction in brain perivascular macrophages, without altering subsequent icv or ip IL-1β-induced reductions in food intake, locomotor activity, and social interactions. In conclusion, the present work shows that icv IL-1β-saporin administration is an efficient way to target brain perivascular macrophages, and to determine whether these cells are involved in IL-1β-induced sickness behavior.
Collapse
|
12
|
Strawn M, Moraes JGN, Safranski TJ, Behura SK. Sexually Dimorphic Transcriptomic Changes of Developing Fetal Brain Reveal Signaling Pathways and Marker Genes of Brain Cells in Domestic Pigs. Cells 2021; 10:2439. [PMID: 34572090 PMCID: PMC8466205 DOI: 10.3390/cells10092439] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 09/09/2021] [Accepted: 09/11/2021] [Indexed: 12/13/2022] Open
Abstract
In this study, transcriptomic changes of the developing brain of pig fetuses of both sexes were investigated on gestation days (GD) 45, 60 and 90. Pig fetal brain grows rapidly around GD60. Consequently, gene expression of the fetal brain was distinctly different on GD90 compared to that of GD45 and GD60. In addition, varying numbers of differentially expressed genes (DEGs) were identified in the male brain compared to the female brain during development. The sex of adjacent fetuses also influenced gene expression of the fetal brain. Extensive changes in gene expression at the exon-level were observed during brain development. Pathway enrichment analysis showed that the ionotropic glutamate receptor pathway and p53 pathway were enriched in the female brain, whereas specific receptor-mediated signaling pathways were enriched in the male brain. Marker genes of neurons and astrocytes were significantly differentially expressed between male and female brains during development. Furthermore, comparative analysis of gene expression patterns between fetal brain and placenta suggested that genes related to ion transportation may play a key role in the regulation of the brain-placental axis in pig. Collectively, the study suggests potential application of pig models to better understand influence of fetal sex on brain development.
Collapse
Affiliation(s)
- Monica Strawn
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA; (M.S.); (T.J.S.); (J.G.N.M.)
| | - Joao G. N. Moraes
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA; (M.S.); (T.J.S.); (J.G.N.M.)
- Department of Animal and Food Sciences, Oklahoma State University, Stillwater, OK 74075, USA
| | - Timothy J. Safranski
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA; (M.S.); (T.J.S.); (J.G.N.M.)
| | - Susanta K. Behura
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA; (M.S.); (T.J.S.); (J.G.N.M.)
- MU Institute for Data Science and Informatics, University of Missouri, Columbia, MO 65211, USA
| |
Collapse
|
13
|
Schäfer AM, Meyer zu Schwabedissen HE, Grube M. Expression and Function of Organic Anion Transporting Polypeptides in the Human Brain: Physiological and Pharmacological Implications. Pharmaceutics 2021; 13:pharmaceutics13060834. [PMID: 34199715 PMCID: PMC8226904 DOI: 10.3390/pharmaceutics13060834] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 05/30/2021] [Accepted: 05/31/2021] [Indexed: 12/17/2022] Open
Abstract
The central nervous system (CNS) is an important pharmacological target, but it is very effectively protected by the blood–brain barrier (BBB), thereby impairing the efficacy of many potential active compounds as they are unable to cross this barrier. Among others, membranous efflux transporters like P-Glycoprotein are involved in the integrity of this barrier. In addition to these, however, uptake transporters have also been found to selectively uptake certain compounds into the CNS. These transporters are localized in the BBB as well as in neurons or in the choroid plexus. Among them, from a pharmacological point of view, representatives of the organic anion transporting polypeptides (OATPs) are of particular interest, as they mediate the cellular entry of a variety of different pharmaceutical compounds. Thus, OATPs in the BBB potentially offer the possibility of CNS targeting approaches. For these purposes, a profound understanding of the expression and localization of these transporters is crucial. This review therefore summarizes the current state of knowledge of the expression and localization of OATPs in the CNS, gives an overview of their possible physiological role, and outlines their possible pharmacological relevance using selected examples.
Collapse
Affiliation(s)
- Anima M. Schäfer
- Biopharmacy, Department Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 50, 4056 Basel, Switzerland; (A.M.S.); (H.E.M.z.S.)
| | - Henriette E. Meyer zu Schwabedissen
- Biopharmacy, Department Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 50, 4056 Basel, Switzerland; (A.M.S.); (H.E.M.z.S.)
| | - Markus Grube
- Center of Drug Absorption and Transport (C_DAT), Department of Pharmacology, University Medicine of Greifswald, 17489 Greifswald, Germany
- Correspondence: ; Tel./Fax: +49-3834-865636
| |
Collapse
|
14
|
Abstract
Thyroid hormone is essential for brain development and brain function in the adult. During development, thyroid hormone acts in a spatial and temporal-specific manner to regulate the expression of genes essential for normal neural cell differentiation, migration, and myelination. In the adult brain, thyroid hormone is important for maintaining normal brain function. Thyroid hormone excess, hyperthyroidism, and thyroid hormone deficiency, hypothyroidism, are associated with disordered brain function, including depression, memory loss, impaired cognitive function, irritability, and anxiety. Adequate thyroid hormone levels are required for normal brain function. Thyroid hormone acts through a cascade of signaling components: activation and inactivation by deiodinase enzymes, thyroid hormone membrane transporters, and nuclear thyroid hormone receptors. Additionally, the hypothalamic-pituitary-thyroid axis, with negative feedback of thyroid hormone on thyrotropin-releasing hormone (TRH) and thyroid-stimulating hormone (TSH) secretion, regulates serum thyroid hormone levels in a narrow range. Animal and human studies have shown both systemic and local reduction in thyroid hormone availability in neurologic disease and after brain trauma. Treatment with thyroid hormone and selective thyroid hormone analogs has resulted in a reduction in injury and improved recovery. This article will describe the thyroid hormone signal transduction pathway in the brain and the role of thyroid hormone in the aging brain, neurologic diseases, and the protective role when administered after traumatic brain injury. © 2021 American Physiological Society. Compr Physiol 11:1-21, 2021.
Collapse
Affiliation(s)
- Yan-Yun Liu
- Department of Medicine, VA Greater Los Angeles Healthcare System, Los Angeles, California, USA.,Departments of Medicine and Physiology, Endocrinology, Diabetes and Metabolism Division, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Gregory A Brent
- Department of Medicine, VA Greater Los Angeles Healthcare System, Los Angeles, California, USA.,Departments of Medicine and Physiology, Endocrinology, Diabetes and Metabolism Division, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| |
Collapse
|
15
|
Ogata S, Ito S, Masuda T, Ohtsuki S. Efficient isolation of brain capillary from a single frozen mouse brain for protein expression analysis. J Cereb Blood Flow Metab 2021; 41:1026-1038. [PMID: 32703112 PMCID: PMC8054721 DOI: 10.1177/0271678x20941449] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Isolated brain capillaries are essential for analyzing the changes of protein expressions at the blood-brain barrier (BBB) under pathological conditions. The standard brain capillary isolation methods require the use of at least five mouse brains in order to obtain a sufficient amount and purity of brain capillaries. The purpose of this study was to establish a brain capillary isolation method from a single mouse brain for protein expression analysis. We successfully isolated brain capillaries from a single frozen mouse brain by using a bead homogenizer in the brain homogenization step and combination of cell strainers and glass beads in the purification step. Western blot and proteomic analysis showed that proteins expressed at the BBB in mouse brain capillaries isolated by the developed method were more enriched than those isolated from a pool of five mouse brains by the standard method. By using the developed method, we further verified the changes in expression of BBB proteins in Glut1-deficient mouse. The developed method is useful for the analysis of various mice models with low numbers and enables us to understand, in more detail, the physiology and pathology of BBB.
Collapse
Affiliation(s)
- Seiryo Ogata
- Department of Pharmaceutical Microbiology, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan
| | - Shingo Ito
- Department of Pharmaceutical Microbiology, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan.,Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Takeshi Masuda
- Department of Pharmaceutical Microbiology, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan.,Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Sumio Ohtsuki
- Department of Pharmaceutical Microbiology, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan.,Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| |
Collapse
|
16
|
Butruille L, Vancamp P, Demeneix BA, Remaud S. Thyroid hormone regulation of adult neural stem cell fate: A comparative analysis between rodents and primates. VITAMINS AND HORMONES 2021; 116:133-192. [PMID: 33752817 DOI: 10.1016/bs.vh.2021.02.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Thyroid hormone (TH) signaling, a highly conserved pathway across vertebrates, is crucial for brain development and function throughout life. In the adult mammalian brain, including that of humans, multipotent neural stem cells (NSCs) proliferate and generate neuronal and glial progenitors. The role of TH has been intensively investigated in the two main neurogenic niches of the adult mouse brain, the subventricular and the subgranular zone. A key finding is that T3, the biologically active form of THs, promotes NSC commitment toward a neuronal fate. In this review, we first discuss the roles of THs in the regulation of adult rodent neurogenesis, as well as how it relates to functional behavior, notably olfaction and cognition. Most research uncovering these roles of TH in adult neurogenesis was conducted in rodents, whose genetic background, brain structure and rate of neurogenesis are considerably different from that of humans. To bridge the phylogenetic gap, we also explore the similarities and divergences of TH-dependent adult neurogenesis in non-human primate models. Lastly, we examine how photoperiodic length changes TH homeostasis, and how that might affect adult neurogenesis in seasonal species to increase fitness. Several aspects by which TH acts on adult NSCs seem to be conserved among mammals, while we only start to uncover the molecular pathways, as well as how other in- and extrinsic factors are intertwined. A multispecies approach delivering more insights in the matter will pave the way for novel NSC-based therapies to combat neurological disorders.
Collapse
Affiliation(s)
- Lucile Butruille
- UMR 7221 Phyma, CNRS/Muséum National d'Histoire Naturelle, Paris, France
| | - Pieter Vancamp
- UMR 7221 Phyma, CNRS/Muséum National d'Histoire Naturelle, Paris, France
| | - Barbara A Demeneix
- UMR 7221 Phyma, CNRS/Muséum National d'Histoire Naturelle, Paris, France
| | - Sylvie Remaud
- UMR 7221 Phyma, CNRS/Muséum National d'Histoire Naturelle, Paris, France.
| |
Collapse
|
17
|
Chen J, Dalirsefat SB, Han D, Dong X, Hua G, Zheng X, Xia T, Shao T, Deng X, Wu C. An EAV-HP insertion in the 5' flanking region of SLCO1B3 is associated with its tissue-expression profile in blue-eggshell Yimeng chickens (Gallus gallus). Poult Sci 2020; 99:6371-6377. [PMID: 33248552 PMCID: PMC7704947 DOI: 10.1016/j.psj.2020.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 08/29/2020] [Accepted: 09/03/2020] [Indexed: 12/15/2022] Open
Abstract
We previously reported that blue eggshell color in chickens is associated with a partial endogenous retroviral (EAV-HP) insertion in the promoter region of the solute carrier organic anion transporter family member 1B3 (SLCO1B3) gene. The EAV-HP sequence includes numerous regulatory elements, which may modulate the expression of adjacent genes. To determine whether this insertion influences the expression of neighboring genes, we screened the expression of solute carrier organic anion transporter family members 1C1, 1B1 (SLCO1C1, SLCO1B1), and SLCO1B3 in 13 and 10 tissues from female and male Yimeng chickens, respectively. We observed that the insertion only significantly modulated the expression of SLCO1B3 and did not majorly affect that of SLCO1C1 and SLCO1B1. High expression of SLCO1B3 was detected in the shell gland, magnum, isthmus, and vagina of the oviduct in female blue-eggshell chickens. We also observed ectopic expression of SLCO1B3 in the testes of male chickens. SLCO1B3 is typically highly expressed in the liver; however, the EAV-HP insertion significantly reduces SLCO1B3 expression. As a liver-specific transporter, a reduction in the expression of SLCO1B3 may affect liver metabolism, particularly that of bile acids. We also detected higher ectopic expression of SLCO1B3 in the lungs of birds heterozygous for the EAV-HP insertion than in homozygous genotypes. In conclusion, we confirmed that the EAV-HP insertion modifies SLCO1B3 expression, and showed, for the first time, similar expression profile of this gene in all parts of the oviduct in females and testis in males. We also observed different levels of SLCO1B3 expression in the liver, which were associated with the EAV-HP insertion, and significantly higher expression in the lungs of birds with heterozygous genotype. The effects of these changes in the SLCO1B3 expression pattern on the function of the tissues warrant further investigation.
Collapse
Affiliation(s)
- Jianfei Chen
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture & Beijing Key Laboratory of Animal Genetic Improvement, China Agricultural University, Beijing 100193, China
| | - Seyed Benyamin Dalirsefat
- Department of Animal Science, Faculty of Agricultural Sciences, University of Guilan, Rasht, Guilan, Iran
| | - Deping Han
- College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Xianggui Dong
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture & Beijing Key Laboratory of Animal Genetic Improvement, China Agricultural University, Beijing 100193, China
| | - Guoying Hua
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture & Beijing Key Laboratory of Animal Genetic Improvement, China Agricultural University, Beijing 100193, China
| | - Xiaotong Zheng
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture & Beijing Key Laboratory of Animal Genetic Improvement, China Agricultural University, Beijing 100193, China
| | - Tianlan Xia
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture & Beijing Key Laboratory of Animal Genetic Improvement, China Agricultural University, Beijing 100193, China
| | - Tianqi Shao
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture & Beijing Key Laboratory of Animal Genetic Improvement, China Agricultural University, Beijing 100193, China
| | - Xuemei Deng
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture & Beijing Key Laboratory of Animal Genetic Improvement, China Agricultural University, Beijing 100193, China.
| | - Changxin Wu
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture & Beijing Key Laboratory of Animal Genetic Improvement, China Agricultural University, Beijing 100193, China
| |
Collapse
|
18
|
Herrmann B, Harder L, Oelkrug R, Chen J, Gachkar S, Nock S, Resch J, Korkowski M, Heuer H, Mittag J. Central Hypothyroidism Impairs Heart Rate Stability and Prevents Thyroid Hormone-Induced Cardiac Hypertrophy and Pyrexia. Thyroid 2020; 30:1205-1216. [PMID: 32188347 DOI: 10.1089/thy.2019.0705] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Background: Tachycardia, cardiac hypertrophy, and elevated body temperature are major signs of systemic hyperthyroidism, which are considered to reflect the excessive thyroid hormone (TH) action in the respective peripheral tissues. However, recent observations indicate that the central actions of TH also contribute substantially to cardiovascular regulation and thermogenesis. Methods: In this study, we dissect the individual contributions of peripheral TH action versus the central effects in body temperature regulation and cardiovascular functions by taking advantage of mice lacking the TH transporters monocarboxylate transporter 8 (MCT8) and organic anion transporting polypeptide 1C1 (OATP1C1) (M/O double knock-out [dko]), which exhibit elevated serum triiodothyronine (T3) levels while their brain is in a profoundly hypothyroid state. We compared these animals with wild-type (WT) mice that were treated orally with T3 to achieve similarly elevated serum T3 levels, but are centrally hyperthyroid. For the studies, we used radiotelemetry, infrared thermography, gene expression profiling, Western blot analyses, and enzyme linked immunosorbent assays (ELISA) assays. Results: Our analyses revealed mild hyperthermia and cardiac hypertrophy in T3-treated WT mice but not in M/O dko animals, suggesting that central actions of TH are required for these hyperthyroid phenotypes. Although the average heart rate was unaffected in either model, the M/O dko exhibited an altered heart rate frequency distribution with tachycardic bursts in active periods and bradycardic episodes during resting time, demonstrating that the stabilization of heart rate by the autonomic nervous system can be impaired in centrally hypothyroid animals. Conclusions: Our studies unravel distinct phenotypical traits of hyperthyroidism that depend on an intact central nervous system, and provide valuable insight into the cardiovascular pathology of the Allan-Herndon-Dudley syndrome, a condition caused by the lack of MCT8 in humans.
Collapse
Affiliation(s)
- Beate Herrmann
- Department of Molecular Endocrinology, Institute for Endocrinology and Diabetes, Center of Brain Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Germany
| | - Lisbeth Harder
- Department of Molecular Endocrinology, Institute for Endocrinology and Diabetes, Center of Brain Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Germany
| | - Rebecca Oelkrug
- Department of Molecular Endocrinology, Institute for Endocrinology and Diabetes, Center of Brain Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Germany
| | - Jiesi Chen
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Sogol Gachkar
- Department of Molecular Endocrinology, Institute for Endocrinology and Diabetes, Center of Brain Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Germany
| | - Sebastian Nock
- Department of Molecular Endocrinology, Institute for Endocrinology and Diabetes, Center of Brain Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Germany
| | - Julia Resch
- Department of Molecular Endocrinology, Institute for Endocrinology and Diabetes, Center of Brain Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Germany
| | - Markus Korkowski
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
- Department of Endocrinology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Heike Heuer
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
- Department of Endocrinology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Jens Mittag
- Department of Molecular Endocrinology, Institute for Endocrinology and Diabetes, Center of Brain Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Germany
| |
Collapse
|
19
|
Pardridge WM. The Isolated Brain Microvessel: A Versatile Experimental Model of the Blood-Brain Barrier. Front Physiol 2020; 11:398. [PMID: 32457645 PMCID: PMC7221163 DOI: 10.3389/fphys.2020.00398] [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: 02/15/2020] [Accepted: 04/02/2020] [Indexed: 12/12/2022] Open
Abstract
A versatile experimental model for the investigation of the blood-brain barrier (BBB), including the neuro-vascular unit, is the isolated brain microvessel preparation. Brain microvessels are primarily comprised of endothelial cells, but also include pericytes, pre-capillary arteriolar smooth muscle cells, astrocyte foot processes, and occasional nerve endings. These microvessels can be isolated from brain with a 3 h procedure, and the microvessels are free of brain parenchyma. Brain microvessels have been isolated from fresh animal brain, fresh human brain obtained at neurosurgery, as well as fresh or frozen autopsy human brain. Brain microvessels are the starting point for isolation of brain microvessel RNA, which then enables the production of BBB cDNA libraries and a genomics analysis of the brain microvasculature. Brain microvessels, combined with quantitative targeted absolute proteomics, allow for the quantitation of specific transporters or receptors expressed at the brain microvasculature. Brain microvessels, combined with specific antibodies and immune labeling of isolated capillaries, allow for the cellular location of proteins expressed within the neuro-vascular unit. Isolated brain microvessels can be used as an “in vitro” preparation of the BBB for the study of the kinetic parameters of BBB carrier-mediated transport (CMT) systems, or for the determination of dissociation constants of peptide binding to BBB receptor-mediated transport (RMT) systems expressed at either the animal or the human BBB. This review will discuss how the isolated brain microvessel model system has advanced our understanding of the organization and functional properties of the BBB, and highlight recent renewed interest in this 50 year old model of the BBB.
Collapse
Affiliation(s)
- William M Pardridge
- Department of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| |
Collapse
|
20
|
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: 98] [Impact Index Per Article: 24.5] [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
|
21
|
Bakos É, Német O, Patik I, Kucsma N, Várady G, Szakács G, Özvegy‐Laczka C. A novel fluorescence‐based functional assay for human OATP1A2 and OATP1C1 identifies interaction between third‐generation P‐gp inhibitors and OATP1A2. FEBS J 2019; 287:2468-2485. [DOI: 10.1111/febs.15156] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 10/16/2019] [Accepted: 11/22/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Éva Bakos
- Membrane Protein Research Group Institute of Enzymology Research Centre for Natural Sciences Hungarian Academy of Sciences Budapest Hungary
| | - Orsolya Német
- Membrane Protein Research Group Institute of Enzymology Research Centre for Natural Sciences Hungarian Academy of Sciences Budapest Hungary
| | - Izabel Patik
- Membrane Protein Research Group Institute of Enzymology Research Centre for Natural Sciences Hungarian Academy of Sciences Budapest Hungary
| | - Nóra Kucsma
- Membrane Protein Research Group Institute of Enzymology Research Centre for Natural Sciences Hungarian Academy of Sciences Budapest Hungary
| | - György Várady
- Laboratory of Molecular Cell Biology Institute of Enzymology Research Centre for Natural Sciences Hungarian Academy of Sciences Budapest Hungary
| | - Gergely Szakács
- Membrane Protein Research Group Institute of Enzymology Research Centre for Natural Sciences Hungarian Academy of Sciences Budapest Hungary
- Institute of Cancer Research Medical University Vienna Wien Austria
| | - Csilla Özvegy‐Laczka
- Membrane Protein Research Group Institute of Enzymology Research Centre for Natural Sciences Hungarian Academy of Sciences Budapest Hungary
| |
Collapse
|
22
|
Taroza S, Rastenytė D, Podlipskytė A, Patamsytė V, Mickuvienė N. Deiodinases, organic anion transporter polypeptide polymorphisms and ischemic stroke outcomes. J Neurol Sci 2019; 407:116457. [PMID: 31677555 DOI: 10.1016/j.jns.2019.116457] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 09/09/2019] [Accepted: 09/10/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Ischemic stroke is a major cause of premature death and chronic disability worldwide, and individual variation in functional outcome is strongly influenced by genetic factors. Neuroendocrine signaling by the hypothalamic-hypophyseal-thyroid axis is a critical regulator of post-stroke pathogenesis, suggesting that allelic variants in thyroid hormone (TH) signaling can influence stroke outcome. AIM To examine associations between acute ischemic stroke (AIS) outcome and allelic variants of the TH metabolizing enzymes deiodinase type 1-3 (DIO1-3) and membrane transporting organic anion polypeptide C1 (OATP1C1). METHODS Eligible AIS patients from Lithuania (n = 248) were genotyped for ten DIO1-3 and OATP1C1 single nucleotide polymorphisms (SNPs): DIO1 rs12095080-A/G, rs11206244-C/T, and rs2235544-A/C; DIO2 rs225014-T/C and rs225015-G/A; DIO3 rs945006-T/G; OATP1C1 rs974453-G/A, rs10444412-T/C, rs10770704-C/T, and rs1515777-A/G. Functional outcome was evaluated one year after index AIS using the modified Rankin Scale. Analyses were adjusted for important confounders, including serum free triiodothyronine. RESULTS After adjustment for potential confounders, the major allelic (wild-type) DIO3 genotype rs945006-TT was associated with better 1-year AIS functional outcome (odds ratio [OR] = 0.25; 95% confidence interval [CI]: 0.08-0.74; p = .013), while the wild-type OATP1C1 genotype rs10770704-CC was associated with poorer outcome (OR = 2.00, 95%CI: 1.04-3.86; p = .038). CONCLUSION Allelic variants in thyroid axis genes may prove useful for prognosis and treatment guidance.
Collapse
Affiliation(s)
- Saulius Taroza
- Laboratory of Behavioral Medicine (Palanga), Neuroscience Institute, Lithuanian University of Health Sciences, Lithuania.
| | - Daiva Rastenytė
- Department of Neurology, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Aurelija Podlipskytė
- Laboratory of Behavioral Medicine (Palanga), Neuroscience Institute, Lithuanian University of Health Sciences, Lithuania
| | - Vaiva Patamsytė
- Institute of Cardiology, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Narseta Mickuvienė
- Laboratory of Behavioral Medicine (Palanga), Neuroscience Institute, Lithuanian University of Health Sciences, Lithuania
| |
Collapse
|
23
|
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
|
24
|
Differential expression and immunoreactivity of thyroid hormone transporters MCT8 and OATP1C1 in rat ovary. Acta Histochem 2019; 121:151440. [PMID: 31561916 DOI: 10.1016/j.acthis.2019.151440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 08/02/2019] [Accepted: 09/03/2019] [Indexed: 11/20/2022]
Abstract
Thyroid hormones (THs) regulate several physiological processes in female mammals, many of which are related to reproduction such as steroidogenesis in the ovary, oocyte and granulosa cells maturation, follicular development and differentiation, and ovulation. THs actions require the presence of THs transporters to facilitate their cellular uptake and efflux. MCT8 and OATP1C1 are the principal THs transporters. The aim of the present study was to determine the gene expression and cellular localization of MCT8 and OATP1C1 in the rat ovary during the diestrus-II cycle phase. Ovaries of virgin adult rats were histologically processed. Reverse Transcription-PCR and immunohistochemistry analyses for MCT8 and OATP1C1 were done. MCT8 gene expression level was significantly higher (P ≤ 0.01) than that of OATP1C1 in the rat ovary. MCT8 and OATP1C1 were found in all types of ovarian cells but with different immunoreactivity. MCT8 showed stronger immunoreactivity in tertiary and Graafian follicles, corpus luteum and blood vessels, whereas OATP1C1's immunoreactivity was stronger in stroma cells, tunica albuginea, and blood vessels. Our results provide evidence that THs and their transporters are both necessary for ovarian function and that any alteration in these transporters could interfere with reproductive processes such as ovulation and steroidogenesis, compromising fertility.
Collapse
|
25
|
Akanuma SI, Kida R, Tsuchiyama A, Tachikawa M, Kubo Y, Hosoya KI. Organic anion-transporting polypeptide 1a4–mediated heterogeneous distribution of sulforhodamine-101 in rat hepatic lobules. Drug Metab Pharmacokinet 2019; 34:239-246. [DOI: 10.1016/j.dmpk.2019.04.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 03/11/2019] [Accepted: 04/05/2019] [Indexed: 01/01/2023]
|
26
|
Helfer G, Barrett P, Morgan PJ. A unifying hypothesis for control of body weight and reproduction in seasonally breeding mammals. J Neuroendocrinol 2019; 31:e12680. [PMID: 30585661 DOI: 10.1111/jne.12680] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 12/18/2018] [Accepted: 12/21/2018] [Indexed: 02/06/2023]
Abstract
Animals have evolved diverse seasonal variations in physiology and reproduction to accommodate yearly changes in environmental and climatic conditions. These changes in physiology are initiated by changes in photoperiod (daylength) and are mediated through melatonin, which relays photoperiodic information to the pars tuberalis of the pituitary gland. Melatonin drives thyroid-stimulating hormone transcription and synthesis in the pars tuberalis, which, in turn, regulates thyroid hormone and retinoic acid synthesis in the tanycytes lining the third ventricle of the hypothalamus. Seasonal variation in central thyroid hormone signalling is conserved among photoperiodic animals. Despite this, different species adopt divergent phenotypes to cope with the same seasonal changes. A common response amongst different species is increased hypothalamic cell proliferation/neurogenesis in short photoperiod. That cell proliferation/neurogenesis may be important for seasonal timing is based on (i) the neurogenic potential of tanycytes; (ii) the fact that they are the locus of striking seasonal morphological changes; and (iii) the similarities to mechanisms involved in de novo neurogenesis of energy balance neurones. We propose that a decrease in hypothalamic thyroid hormone and retinoic acid signalling initiates localised neurodegeneration and apoptosis, which leads to a reduction in appetite and body weight. Neurodegeneration induces compensatory cell proliferation from the neurogenic niche in tanycytes and new cells are born under short photoperiod. Because these cells have the potential to differentiate into a number of different neuronal phenotypes, this could provide a mechanistic basis to explain the seasonal regulation of energy balance, as well as reproduction. This cycle can be achieved without changes in thyroid hormone/retinoic acid and explains recent data obtained from seasonal animals held in natural conditions. However, thyroid/retinoic acid signalling is required to synchronise the cycles of apoptosis, proliferation and differentiation. Thus, hypothalamic neurogenesis provides a framework to explain diverse photoperiodic responses.
Collapse
Affiliation(s)
- Gisela Helfer
- School of Chemistry and Biosciences, University of Bradford, Bradford, UK
| | - Perry Barrett
- Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, UK
| | - Peter J Morgan
- Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, UK
| |
Collapse
|
27
|
Hartz AMS, Schulz JA, Sokola BS, Edelmann SE, Shen AN, Rempe RG, Zhong Y, Seblani NE, Bauer B. Isolation of Cerebral Capillaries from Fresh Human Brain Tissue. J Vis Exp 2018. [PMID: 30272660 DOI: 10.3791/57346] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Understanding blood-brain barrier function under physiological and pathophysiological conditions is critical for the development of new therapeutic strategies that hold the promise to enhance brain drug delivery, improve brain protection, and treat brain disorders. However, studying the human blood-brain barrier function is challenging. Thus, there is a critical need for appropriate models. In this regard, brain capillaries isolated from human brain tissue represent a unique tool to study barrier function as close to the human in vivo situation as possible. Here, we describe an optimized protocol to isolate capillaries from human brain tissue at a high yield and with consistent quality and purity. Capillaries are isolated from fresh human brain tissue using mechanical homogenization, density-gradient centrifugation, and filtration. After the isolation, the human brain capillaries can be used for various applications including leakage assays, live cell imaging, and immune-based assays to study protein expression and function, enzyme activity, or intracellular signaling. Isolated human brain capillaries are a unique model to elucidate the regulation of the human blood-brain barrier function. This model can provide insights into central nervous system (CNS) pathogenesis, which will help the development of therapeutic strategies for treating CNS disorders.
Collapse
Affiliation(s)
- Anika M S Hartz
- Sanders-Brown Center on Aging, Department of Pharmacology and Nutritional Sciences, University of Kentucky
| | - Julia A Schulz
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky
| | - Brent S Sokola
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky
| | - Stephanie E Edelmann
- Sanders-Brown Center on Aging, Department of Pharmacology and Nutritional Sciences, University of Kentucky
| | - Andrew N Shen
- Sanders-Brown Center on Aging, Department of Pharmacology and Nutritional Sciences, University of Kentucky
| | - Ralf G Rempe
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky
| | - Yu Zhong
- Sanders-Brown Center on Aging, Department of Pharmacology and Nutritional Sciences, University of Kentucky
| | | | - Bjoern Bauer
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky;
| |
Collapse
|
28
|
Vancamp P, Darras VM. From zebrafish to human: A comparative approach to elucidate the role of the thyroid hormone transporter MCT8 during brain development. Gen Comp Endocrinol 2018; 265:219-229. [PMID: 29183795 DOI: 10.1016/j.ygcen.2017.11.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 11/24/2017] [Accepted: 11/24/2017] [Indexed: 02/07/2023]
Abstract
Monocarboxylate transporter 8 (MCT8) facilitates transmembrane transport of thyroid hormones (THs) ensuring their action on gene expression during vertebrate neurodevelopment. A loss of MCT8 in humans results in severe psychomotor deficits associated with the Allan-Herndon-Dudley Syndrome (AHDS). However, where and when exactly a lack of MCT8 causes the neurological manifestations remains unclear because of the varying expression pattern of MCT8 between specific brain regions and cells. Here, we elaborate on the animal models that have been generated to elucidate the mechanisms underlying MCT8-deficient brain development. The absence of a clear neurological phenotype in Mct8 knockout mice made it clear that a single species would not suffice. The evolutionary conservation of TH action on neurodevelopment as well as the components regulating TH signalling however offers the opportunity to answer different aspects of MCT8 function in brain development using different vertebrate species. Moreover, the plethora of tools for genome editing available today facilitates gene silencing in these animals as well. Studies in the recently generated mct8-deficient zebrafish and Mct8/Oatp1c1 double knockout mice have put forward the current paradigm of impaired TH uptake at the level of the blood-brain barrier during peri- and postnatal development as being the main pathophysiological mechanism of AHDS. RNAi vector-based, cell-specific induction of MCT8 knockdown in the chicken embryo points to an additional function of MCT8 at the level of the neural progenitors during early brain development. Future studies including also additional in vivo models like Xenopus or in vitro approaches such as induced pluripotent stem cells will continue to help unravelling the exact role of MCT8 in developmental events. In the end, this multispecies approach will lead to a unifying thesis regarding the cellular and molecular mechanisms responsible for the neurological phenotype in AHDS patients.
Collapse
Affiliation(s)
- Pieter Vancamp
- KU Leuven, Laboratory of Comparative Endocrinology, Department of Biology, B-3000 Leuven, Belgium
| | - Veerle M Darras
- KU Leuven, Laboratory of Comparative Endocrinology, Department of Biology, B-3000 Leuven, Belgium.
| |
Collapse
|
29
|
Comparative Analysis of Zearalenone Effects on Thyroid Receptor Alpha (TRα) and Beta (TRβ) Expression in Rat Primary Cerebellar Cell Cultures. Int J Mol Sci 2018; 19:ijms19051440. [PMID: 29751674 PMCID: PMC5983839 DOI: 10.3390/ijms19051440] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 04/20/2018] [Accepted: 05/09/2018] [Indexed: 12/22/2022] Open
Abstract
Thyroid receptors play an important role in postnatal brain development. Zearalenone (ZEN), a major mycotoxin of Fusarium fungi, is well known to cause serious health problems in animals and humans through various mechanisms, including the physiological pathways of thyroid hormone (TH). In the present study, we aimed to investigate the expression of thyroid receptors α (TRα) and β (TRβ) in primary cerebellar neurons in the presence or absence of glia and following ZEN treatment, using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot. Primary cerebellar granule cells were treated with low doses of ZEN (0.1 nM) in combination with physiologically relevant concentrations of l-thyroxine (T4), 3,3′,5-triiodo-l-thyronine (T3) and 17β-estradiol (E2). Expression levels of TRα and TRβ at mRNA and protein levels were slightly modified by ZEN administered alone; however, along with thyroid and steroid hormones, modelling the physiological conditions, expression levels of TRs varied highly depending on the given treatment. Gene expression levels were also highly modulated by the presence or absence of glial cells, with mostly contrasting effects. Our results demonstrate divergent transcriptional and translational mechanisms involved in the expression of TRs implied by ZEN and hormonal milieu, as well as culturing conditions.
Collapse
|
30
|
Kubo Y, Akanuma SI, Hosoya KI. Recent advances in drug and nutrient transport across the blood-retinal barrier. Expert Opin Drug Metab Toxicol 2018; 14:513-531. [PMID: 29719158 DOI: 10.1080/17425255.2018.1472764] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
INTRODUCTION The blood-retinal barrier (BRB) is the barrier separating the blood and neural retina, and transport systems for low-weight molecules at the BRB are expected to be useful for developing drugs for the treatment of ocular neural disorders and maintaining a healthy retina. Areas covered: This review discusses blood-to-retina and retina-to-blood transport of drugs and nutrients at the BRB. In particular, P-gp (ABCB1/MDR1) has low impact on the transport of cationic drugs at the BRB, suggesting a significant role of novel organic cation transporters in influx and efflux transport of lipophilic cationic drugs between blood and the retina. The transport of pravastatin at the BRB involves transporters including organic anion transporting polypeptide 1a4 (Oatp1a4). Recent studies have shown the involvement of solute carrier transporters in the blood-to-retina transport of nutrients including riboflavin, L-ornithine, β-alanine, and L-histidine, implying that dipeptide transport at the BRB is minimal. Expert opinion: Novel organic cation transport systems and the elimination-dominant transport of pravastatin at the BRB are expected to be useful in systemic drug delivery to the neural retina without CNS side effects. The mechanism of nutrient transport at the BRB is expected to provide a new strategy for delivery of nutrient-mimetic drugs.
Collapse
Affiliation(s)
- Yoshiyuki Kubo
- a Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences , University of Toyama , Toyama , Japan
| | - Shin-Ichi Akanuma
- a Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences , University of Toyama , Toyama , Japan
| | - Ken-Ichi Hosoya
- a Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences , University of Toyama , Toyama , Japan
| |
Collapse
|
31
|
Meyer zu Schwabedissen HE, Ferreira C, Schaefer AM, Oufir M, Seibert I, Hamburger M, Tirona RG. Thyroid Hormones Are Transport Substrates and Transcriptional Regulators of Organic Anion Transporting Polypeptide 2B1. Mol Pharmacol 2018; 94:700-712. [DOI: 10.1124/mol.117.111161] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 05/02/2018] [Indexed: 01/05/2023] Open
|
32
|
Tatke A, Janga KY, Avula B, Wang X, Jablonski MM, Khan IA, Majumdar S. P-glycoprotein Restricts Ocular Penetration of Loperamide across the Blood-Ocular Barriers: a Comparative Study in Mdr1a Knock-out and Wild Type Sprague Dawley Rats. AAPS PharmSciTech 2018. [PMID: 29520587 DOI: 10.1208/s12249-018-0979-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The current research was undertaken to determine the existence and magnitude of P-glycoprotein (P-gp) expression on the blood-ocular barriers by studying the ocular penetration of loperamide, a specific P-gp substrate, in P-gp (Mdr1a) knock-out (KO) and wild type (WT) Sprague Dawley rats. A clear, stable, sterile solution of loperamide (1 mg/mL), for intravenous administration, was formulated and evaluated. Ocular distribution was studied in P-gp KO and WT rats following intravenous administration of loperamide (at two doses). The drug levels in plasma, aqueous humor (AH), and vitreous humor (VH) samples were determined with the aid of UHPLC-Q-TOF-MS/MS, and the AH/plasma (D AH ) and VH/plasma (D VH ) distribution ratios were estimated. Electroretinography (ERG), ultrastructural analyses, and histology studies were carried out, in both KO and WT rats, to detect any drug-induced functional and/or structural alterations in the retina. Dose-related loperamide levels were observed in the plasma of both WT and KO rats. The loperamide concentrations in the AH and VH of KO rats were significantly higher compared to that observed in the WT rats, at the lower dose. However, a marked increase in the D AH and D VH was noted in the KO rats. ERG, ultrastructure, and histology studies did not indicate any drug-induced toxic effects in the retina under the test conditions. The results from these studies demonstrate that P-gp blocks the penetration of loperamide into the ocular tissues from the systemic circulation and that the effect is more pronounced at lower plasma loperamide concentrations.
Collapse
|
33
|
Brozaitiene J, Skiriute D, Burkauskas J, Podlipskyte A, Jankauskiene E, Serretti A, Mickuviene N. Deiodinases, Organic Anion Transporter Polypeptide Polymorphisms, and Thyroid Hormones in Patients with Myocardial Infarction. Genet Test Mol Biomarkers 2018; 22:270-278. [DOI: 10.1089/gtmb.2017.0283] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Affiliation(s)
- Julija Brozaitiene
- Laboratory of Behavioral Medicine, Neuroscience Institute, Lithuanian University of Health Sciences, Palanga, Lithuania
| | - Daina Skiriute
- Laboratory of Molecular Neurooncology, Neuroscience Institute, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Julius Burkauskas
- Laboratory of Behavioral Medicine, Neuroscience Institute, Lithuanian University of Health Sciences, Palanga, Lithuania
| | - Aurelija Podlipskyte
- Laboratory of Behavioral Medicine, Neuroscience Institute, Lithuanian University of Health Sciences, Palanga, Lithuania
| | - Edita Jankauskiene
- Department of Cardiology, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Alessandro Serretti
- Department of Biomedical and NeuroMotor Sciences, University of Bologna, Bologna, Italy
| | - Narseta Mickuviene
- Laboratory of Behavioral Medicine, Neuroscience Institute, Lithuanian University of Health Sciences, Palanga, Lithuania
| |
Collapse
|
34
|
Clasadonte J, Prevot V. The special relationship: glia-neuron interactions in the neuroendocrine hypothalamus. Nat Rev Endocrinol 2018; 14:25-44. [PMID: 29076504 DOI: 10.1038/nrendo.2017.124] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Natural fluctuations in physiological conditions require adaptive responses involving rapid and reversible structural and functional changes in the hypothalamic neuroendocrine circuits that control homeostasis. Here, we discuss the data that implicate hypothalamic glia in the control of hypothalamic neuroendocrine circuits, specifically neuron-glia interactions in the regulation of neurosecretion as well as neuronal excitability. Mechanistically, the morphological plasticity displayed by distal processes of astrocytes, pituicytes and tanycytes modifies the geometry and diffusion properties of the extracellular space. These changes alter the relationship between glial cells of the hypothalamus and adjacent neuronal elements, especially at specialized intersections such as synapses and neurohaemal junctions. The structural alterations in turn lead to functional plasticity that alters the release and spread of neurotransmitters, neuromodulators and gliotransmitters, as well as the activity of discrete glial signalling pathways that mediate feedback by peripheral signals to the hypothalamus. An understanding of the contributions of these and other non-neuronal cell types to hypothalamic neuroendocrine function is thus critical both to understand physiological processes such as puberty, the maintenance of bodily homeostasis and ageing and to develop novel therapeutic strategies for dysfunctions of these processes, such as infertility and metabolic disorders.
Collapse
Affiliation(s)
- Jerome Clasadonte
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Centre, U1172, Bâtiment Biserte, 1 Place de Verdun, 59045, Lille, Cedex, France
- University of Lille, FHU 1000 days for Health, School of Medicine, Lille 59000, France
| | - Vincent Prevot
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Centre, U1172, Bâtiment Biserte, 1 Place de Verdun, 59045, Lille, Cedex, France
- University of Lille, FHU 1000 days for Health, School of Medicine, Lille 59000, France
| |
Collapse
|
35
|
|
36
|
Vancamp P, Darras VM. Dissecting the role of regulators of thyroid hormone availability in early brain development: Merits and potential of the chicken embryo model. Mol Cell Endocrinol 2017; 459:71-78. [PMID: 28153797 DOI: 10.1016/j.mce.2017.01.045] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 01/24/2017] [Accepted: 01/26/2017] [Indexed: 10/20/2022]
Abstract
Thyroid hormones (THs) are important mediators of vertebrate central nervous system (CNS) development, thereby regulating the expression of a wide variety of genes by binding to nuclear TH receptors. TH transporters and deiodinases are both needed to ensure appropriate intracellular TH availability, but the precise function of each of these regulators and their coaction during brain development is only partially understood. Rodent knockout models already provided some crucial insights, but their in utero development severely hampers research regarding the role of TH regulators during early embryonic stages. The establishment of novel gain- and loss-of-function techniques has boosted the position of externally developing non-mammalian vertebrates as research models in developmental endocrinology. Here, we elaborate on the chicken as a model organism to elucidate the function of TH regulators during embryonic CNS development. The fast-developing, relatively big and accessible embryo allows easy experimental manipulation, especially at early stages of brain development. Recent data on the characterisation and spatiotemporal expression pattern of different TH regulators in embryonic chicken CNS have provided the necessary background to dissect the function of each of them in more detail. We highlight some recent advances and important strategies to investigate the role of TH transporters and deiodinases in various CNS structures like the brain barriers, the cerebellum, the retina and the hypothalamus. Exploiting the advantages of this non-classical model can greatly contribute to complete our understanding of the regulation of TH bioavailability throughout embryonic CNS development.
Collapse
Affiliation(s)
- Pieter Vancamp
- KU Leuven, Laboratory of Comparative Endocrinology, Department of Biology, B-3000, Leuven, Belgium
| | - Veerle M Darras
- KU Leuven, Laboratory of Comparative Endocrinology, Department of Biology, B-3000, Leuven, Belgium.
| |
Collapse
|
37
|
Wirth EK, Meyer F. Neuronal effects of thyroid hormone metabolites. Mol Cell Endocrinol 2017; 458:136-142. [PMID: 28088465 DOI: 10.1016/j.mce.2017.01.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 01/06/2017] [Accepted: 01/07/2017] [Indexed: 12/19/2022]
Abstract
Thyroid hormones and their metabolites are active regulators of gene expression, mitochondrial function and various other physiological actions in different organs and tissues. These actions are mediated by a spatio-temporal regulation of thyroid hormones and metabolites within a target cell. This spatio-temporal resolution as well as classical and non-classical actions of thyroid hormones and metabolites is accomplished and regulated on multiple levels as uptake, local activation and signaling of thyroid hormones. In this review, we will give an overview of the systems involved in regulating the presence and activity of thyroid hormones and their metabolites within the brain, specifically in neurons. While a wealth of data on thyroxin (T4) and 3,5,3'-triiodothyronine (T3) in the brain has been generated, research into the presence of action of other thyroid hormone metabolites is still sparse and requires further investigations.
Collapse
Affiliation(s)
- Eva K Wirth
- Institut für Experimentelle Endokrinologie, Charité-Universitätsmedizin Berlin, Berlin, Germany.
| | - Franziska Meyer
- Institut für Experimentelle Endokrinologie, Charité-Universitätsmedizin Berlin, Berlin, Germany
| |
Collapse
|
38
|
Zubkov EA, Zorkina YA, Gurina OI, Melnikov PA, Morozova AY, Chekhonin VP. Prenatal exposure to brain-specific anion transporter-1-specific monoclonal antibodies impairs cognitive function in post-natal life. Neuropeptides 2017; 65:100-105. [PMID: 28688524 DOI: 10.1016/j.npep.2017.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 04/21/2017] [Accepted: 07/02/2017] [Indexed: 11/22/2022]
Abstract
Subclinical hypothyroidism is caused by thyroid hormone deficit and can lead to impairments in mood and cognition. In brain, supply with thyroxine (T4) is mediated by thyroid hormone transporters including the brain-specific anion transporter-1 (BSAT-1). In humans and rodents, BSAT-1 is expressed in brain microvessels and astrocytes. In this study, we tested whether exposure in utero with BSAT-1-specific monoclonal antibodies (MabBSAT) will affect the cognitive function of the progeny. On gestation day 16th, females were intravenously treated with MabBSAT, non-specific antibodies (control 1), and saline (control 2). 72h after injection, MabBSAT were still detectable in the rat brain while non-specific antibodies were found. Immunocytochemistry showed that MabBSAT can bind to cultured primary cerebrovascular rat cells. At the age of 1month, the progeny was subjected to the Y-maze test, novel object recognition test, passive avoidance test, and Morris water maze, which revealed significant impairments in the cognitive function in the MabBSAT-exposed progeny compared to both control progeny groups. Therefore, prenatal exposure to MabBSAT blocks brain BSAT-1 and limits T4 influx to the brain. This impairs the cognitive function in exposed progeny in the post-natal life.
Collapse
Affiliation(s)
- Eugene A Zubkov
- Department of Fundamental and Applied Neurobiology, Serbsky Federal Research Center of Psychiatry and Narcology, Kropotkinsky lane 23, 119991 Moscow, Russia.
| | - Yana A Zorkina
- Department of Fundamental and Applied Neurobiology, Serbsky Federal Research Center of Psychiatry and Narcology, Kropotkinsky lane 23, 119991 Moscow, Russia
| | - Olga I Gurina
- Department of Fundamental and Applied Neurobiology, Serbsky Federal Research Center of Psychiatry and Narcology, Kropotkinsky lane 23, 119991 Moscow, Russia
| | - Pavel A Melnikov
- Department of Fundamental and Applied Neurobiology, Serbsky Federal Research Center of Psychiatry and Narcology, Kropotkinsky lane 23, 119991 Moscow, Russia
| | - Anna Y Morozova
- Department of Fundamental and Applied Neurobiology, Serbsky Federal Research Center of Psychiatry and Narcology, Kropotkinsky lane 23, 119991 Moscow, Russia
| | - Vladimir P Chekhonin
- Department of Fundamental and Applied Neurobiology, Serbsky Federal Research Center of Psychiatry and Narcology, Kropotkinsky lane 23, 119991 Moscow, Russia; Department of Medical Nanobiotechnology, Pirogov Russian National Research Medical University, Ostrovitianov str. 1, 117997 Moscow, Russia.
| |
Collapse
|
39
|
Noda M. Thyroid Hormone in the CNS: Contribution of Neuron-Glia Interaction. VITAMINS AND HORMONES 2017; 106:313-331. [PMID: 29407440 DOI: 10.1016/bs.vh.2017.05.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The endocrine system and the central nervous system (CNS) are intimately linked. Among hormones closely related to the nervous system, thyroid hormones (THs) are critical for the regulation of development and differentiation of neurons and neuroglia and hence for development and function of the CNS. T3 (3,3',5-triiodothyronine), an active form of TH, is important not only for neuronal development but also for differentiation of astrocytes and oligodendrocytes, and for microglial development. In adult brain, T3 affects glial morphology with sex- and age-dependent manner and therefore may affect their function, leading to influence on neuron-glia interaction. T3 is an important signaling factor that affects microglial functions such as migration and phagocytosis via complex mechanisms. Therefore, dysfunction of THs may impair glial function as well as neuronal function and thus disturb the brain, which may cause mental disorders. Investigations on molecular and cellular basis of hyperthyroidism and hypothyroidism will help us to understand changes in neuron-glia interaction and therefore consequent psychiatric symptoms.
Collapse
Affiliation(s)
- Mami Noda
- Laboratory of Pathophysiology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.
| |
Collapse
|
40
|
Yang Z, Kuboyama T, Tohda C. A Systematic Strategy for Discovering a Therapeutic Drug for Alzheimer's Disease and Its Target Molecule. Front Pharmacol 2017; 8:340. [PMID: 28674493 PMCID: PMC5474478 DOI: 10.3389/fphar.2017.00340] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 05/19/2017] [Indexed: 11/13/2022] Open
Abstract
Natural medicines are attractive sources of leading compounds that can be used as interventions for neurodegenerative disorders. The complexity of their chemical components and undetermined bio-metabolism have greatly hindered both the use of natural medicines and the identification of their active constituents. Here, we report a systematic strategy for evaluating the bioactive candidates in natural medicines used for Alzheimer's disease (AD). We found that Drynaria Rhizome could enhance memory function and ameliorate AD pathologies in 5XFAD mice. Biochemical analysis led to the identification of the bio-effective metabolites that are transferred to the brain, namely, naringenin and its glucuronides. To explore the mechanism of action, we combined the drug affinity responsive target stability with immunoprecipitation-liquid chromatography/mass spectrometry analysis, identifying the collapsin response mediator protein 2 protein as a target of naringenin. Our study indicates that biochemical analysis coupled with pharmacological methods can be used in the search for new targets for AD intervention.
Collapse
Affiliation(s)
- Zhiyou Yang
- Division of Neuromedical Science, Department of Bioscience, Institute of Natural Medicine, University of ToyamaToyama, Japan
| | - Tomoharu Kuboyama
- Division of Neuromedical Science, Department of Bioscience, Institute of Natural Medicine, University of ToyamaToyama, Japan
| | - Chihiro Tohda
- Division of Neuromedical Science, Department of Bioscience, Institute of Natural Medicine, University of ToyamaToyama, Japan
| |
Collapse
|
41
|
Protze J, Braun D, Hinz KM, Bayer-Kusch D, Schweizer U, Krause G. Membrane-traversing mechanism of thyroid hormone transport by monocarboxylate transporter 8. Cell Mol Life Sci 2017; 74:2299-2318. [PMID: 28132097 PMCID: PMC11107705 DOI: 10.1007/s00018-017-2461-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 12/14/2016] [Accepted: 01/09/2017] [Indexed: 12/22/2022]
Abstract
Monocarboxylate transporter 8 (MCT8) mediates thyroid hormone (TH) transport across the plasma membrane in many cell types. In order to better understand its mechanism, we have generated three new MCT8 homology models based on sugar transporters XylE in the intracellular opened (PDB ID: 4aj4) and the extracellular partly occluded (PDB ID: 4gby) conformations as well as FucP (PDB ID: 3o7q) and GLUT3 (PDB ID: 4zwc) in the fully extracellular opened conformation. T3-docking studies from both sides revealed interactions with His192, His415, Arg445 and Asp498 as previously identified. Selected mutations revealed further transport-sensitive positions mainly at the discontinuous transmembrane helices TMH7 and 10. Lys418 is potentially involved in neutralising the charge of the TH substrate because it can be replaced by charged, but not by uncharged, amino acids. The side chain of Thr503 was hypothesised to stabilise a helix break at TMH10 that undergoes a prominent local shift during the transport cycle. A T503V mutation accordingly affected transport. The aromatic Tyr419, the polar Ser313 and Ser314 as well as the charged Glu422 and Glu423 lining the transport channel have been studied. Based on related sugar transporters, we suggest an alternating access mechanism for MCT8 involving a series of amino acid positions previously and newly identified as critical for transport.
Collapse
Affiliation(s)
- Jonas Protze
- Leibniz-Institut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125, Berlin, Germany
| | - Doreen Braun
- Institut für Biochemie und Molekularbiologie, Rheinische Friedrich-Wilhelms-Universität, 53115, Bonn, Germany
| | - Katrin Manuela Hinz
- Leibniz-Institut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125, Berlin, Germany
| | - Dorothea Bayer-Kusch
- Institut für Biochemie und Molekularbiologie, Rheinische Friedrich-Wilhelms-Universität, 53115, Bonn, Germany
| | - Ulrich Schweizer
- Institut für Biochemie und Molekularbiologie, Rheinische Friedrich-Wilhelms-Universität, 53115, Bonn, Germany.
| | - Gerd Krause
- Leibniz-Institut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125, Berlin, Germany.
| |
Collapse
|
42
|
Saidijam M, Karimi Dermani F, Sohrabi S, Patching SG. Efflux proteins at the blood-brain barrier: review and bioinformatics analysis. Xenobiotica 2017; 48:506-532. [PMID: 28481715 DOI: 10.1080/00498254.2017.1328148] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
1. Efflux proteins at the blood-brain barrier provide a mechanism for export of waste products of normal metabolism from the brain and help to maintain brain homeostasis. They also prevent entry into the brain of a wide range of potentially harmful compounds such as drugs and xenobiotics. 2. Conversely, efflux proteins also hinder delivery of therapeutic drugs to the brain and central nervous system used to treat brain tumours and neurological disorders. For bypassing efflux proteins, a comprehensive understanding of their structures, functions and molecular mechanisms is necessary, along with new strategies and technologies for delivery of drugs across the blood-brain barrier. 3. We review efflux proteins at the blood-brain barrier, classified as either ATP-binding cassette (ABC) transporters (P-gp, BCRP, MRPs) or solute carrier (SLC) transporters (OATP1A2, OATP1A4, OATP1C1, OATP2B1, OAT3, EAATs, PMAT/hENT4 and MATE1). 4. This includes information about substrate and inhibitor specificity, structural organisation and mechanism, membrane localisation, regulation of expression and activity, effects of diseases and conditions and the principal technique used for in vivo analysis of efflux protein activity: positron emission tomography (PET). 5. We also performed analyses of evolutionary relationships, membrane topologies and amino acid compositions of the proteins, and linked these to structure and function.
Collapse
Affiliation(s)
- Massoud Saidijam
- a Department of Molecular Medicine and Genetics , Research Centre for Molecular Medicine, School of Medicine, Hamadan University of Medical Sciences , Hamadan , Iran and
| | - Fatemeh Karimi Dermani
- a Department of Molecular Medicine and Genetics , Research Centre for Molecular Medicine, School of Medicine, Hamadan University of Medical Sciences , Hamadan , Iran and
| | - Sareh Sohrabi
- a Department of Molecular Medicine and Genetics , Research Centre for Molecular Medicine, School of Medicine, Hamadan University of Medical Sciences , Hamadan , Iran and
| | - Simon G Patching
- b School of BioMedical Sciences and the Astbury Centre for Structural Molecular Biology, University of Leeds , Leeds , UK
| |
Collapse
|
43
|
Zibara K, Zein NE, Sabra M, Hneino M, Harati H, Mohamed W, Kobeissy FH, Kassem N. Thyroxine (T 4) Transfer from Blood to Cerebrospinal Fluid in Sheep Isolated Perfused Choroid Plexus: Role of Multidrug Resistance-Associated Proteins and Organic Anion Transporting Polypeptides. Front Neurol 2017; 8:214. [PMID: 28588548 PMCID: PMC5440555 DOI: 10.3389/fneur.2017.00214] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 05/02/2017] [Indexed: 11/21/2022] Open
Abstract
Thyroxine (T4) enters the brain either directly across the blood–brain barrier (BBB) or indirectly via the choroid plexus (CP), which forms the blood–cerebrospinal fluid barrier (B-CSF-B). In this study, using isolated perfused CP of the sheep by single-circulation paired tracer and steady-state techniques, T4 transport mechanisms from blood into lateral ventricle CP has been characterized as the first step in the transfer across the B-CSF-B. After removal of sheep brain, the CPs were perfused with 125I-T4 and 14C-mannitol. Unlabeled T4 was applied during single tracer technique to assess the mode of maximum uptake (Umax) and the net uptake (Unet) on the blood side of the CP. On the other hand, in order to characterize T4 protein transporters, steady-state extraction of 125I-T4 was measured in presence of different inhibitors such as probenecid, verapamil, BCH, or indomethacin. Increasing the concentration of unlabeled-T4 resulted in a significant reduction in Umax%, which was reflected by a complete inhibition of T4 uptake into CP. In fact, the obtained Unet% decreased as the concentration of unlabeled-T4 increased. The addition of probenecid caused a significant inhibition of T4 transport, in comparison to control, reflecting the presence of a carrier mediated process at the basolateral side of the CP and the involvement of multidrug resistance-associated proteins (MRPs: MRP1 and MRP4) and organic anion transporting polypeptides (Oatp1, Oatp2, and Oatp14). Moreover, verapamil, the P-glycoprotein (P-gp) substrate, resulted in ~34% decrease in the net extraction of T4, indicating that MDR1 contributes to T4 entry into CSF. Finally, inhibition in the net extraction of T4 caused by BCH or indomethacin suggests, respectively, a role for amino acid “L” system and MRP1/Oatp1 in mediating T4 transfer. The presence of a carrier-mediated transport mechanism for cellular uptake on the basolateral membrane of the CP, mainly P-gp and Oatp2, would account for the efficient T4 transport from blood to CSF. The current study highlights a carrier-mediated transport mechanism for T4 movement from blood to brain at the basolateral side of B-CSF-B/CP, as an alternative route to BBB.
Collapse
Affiliation(s)
- Kazem Zibara
- ER045, PRASE, Lebanese University, Beirut, Lebanon.,Faculty of Sciences, Biology Department, Lebanese University, Beirut, Lebanon
| | - Nabil El Zein
- ER045, PRASE, Lebanese University, Beirut, Lebanon.,Faculty of Sciences, Biology Department, Lebanese University, Beirut, Lebanon
| | - Mirna Sabra
- ER045, PRASE, Lebanese University, Beirut, Lebanon.,Neuroscience Research Centre, Faculty of Medical Sciences, Lebanese University, Beirut, Lebanon
| | - Mohammad Hneino
- ER045, PRASE, Lebanese University, Beirut, Lebanon.,Faculty of Public Health, Medical Laboratory Department, Lebanese University, Beirut, Lebanon
| | - Hayat Harati
- Neuroscience Research Centre, Faculty of Medical Sciences, Lebanese University, Beirut, Lebanon
| | - Wael Mohamed
- Basic Medical Science Department, Kulliyyah of Medicine, International Islamic University Malaysia, Kuantan, Pahang, Malaysia.,Neuroscience Unit, Menoufia Medical School, Cairo, Egypt
| | - Firas H Kobeissy
- Department of Biochemistry and Molecular Genetics, American University of Beirut, Beirut, Lebanon
| | - Nouhad Kassem
- ER045, PRASE, Lebanese University, Beirut, Lebanon.,Neuroscience Research Centre, Faculty of Medical Sciences, Lebanese University, Beirut, Lebanon
| |
Collapse
|
44
|
Taskar KS, Mariappan TT, Kurawattimath V, Singh Gautam S, Radhakrishna Mullapudi TV, Sridhar SK, Kallem RR, Marathe P, Mandlekar S. Unmasking the Role of Uptake Transporters for Digoxin Uptake Across the Barriers of the Central Nervous System in Rat. J Cent Nerv Syst Dis 2017; 9:1179573517693596. [PMID: 28469522 PMCID: PMC5392048 DOI: 10.1177/1179573517693596] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 01/22/2017] [Indexed: 12/23/2022] Open
Abstract
The role of uptake transporter (organic anion–transporting polypeptide [Oatp]) in the disposition of a P-glycoprotein (P-gp) substrate (digoxin) at the barriers of central nervous system, namely, the blood-brain barrier (BBB), blood-spinal cord barrier (BSCB), and brain-cerebrospinal fluid barrier (BCSFB), was studied using rat as a preclinical species. In vivo chemical inhibition of P-gp and Oatp was achieved using elacridar and rifampicin, respectively. Our findings show that (1) digoxin had a low brain-to-plasma concentration ratio (B/P) (0.07) in rat; (2) in the presence of elacridar, the B/P of digoxin increased by about 12-fold; (3) rifampicin administration alone did not change the digoxin B/P significantly when compared with digoxin B/P alone; (4) rifampicin administration along with elacridar resulted only in 6-fold increase in the B/P of digoxin; (5) similar fold changes and trends were seen with the spinal cord-to-plasma concentration ratio of digoxin, indicating the similarity between BBB and the BSCB; and (6) unlike BBB and BSCB, the presence of rifampicin further increased the cerebrospinal fluid-to-plasma concentration ratio (CSF/P) for digoxin, suggesting a differential orientation of the uptake transporters at the BCSFB (CSF to blood) compared with the BBB (blood to brain). The observations for digoxin uptake, at least at the BBB and the BSCB, advocate the importance of uptake transporters (Oatps). However, the activity of such uptake transporters became evident only after inhibition of the efflux transporter (P-gp).
Collapse
Affiliation(s)
- Kunal S Taskar
- Pharmaceutical Candidate Optimization, Biocon Bristol-Myers Squibb Research & Development Center (BBRC), Syngene International Limited, Bangalore, India.,Mechanistic Safety and Disposition, IVIVT, GlaxoSmithKline, Ware, UK
| | - T Thanga Mariappan
- Pharmaceutical Candidate Optimization, Biocon Bristol-Myers Squibb Research & Development Center (BBRC), Syngene International Limited, Bangalore, India
| | - Vishwanath Kurawattimath
- Pharmaceutical Candidate Optimization, Biocon Bristol-Myers Squibb Research & Development Center (BBRC), Syngene International Limited, Bangalore, India
| | - Shashyendra Singh Gautam
- Pharmaceutical Candidate Optimization, Biocon Bristol-Myers Squibb Research & Development Center (BBRC), Syngene International Limited, Bangalore, India
| | - T V Radhakrishna Mullapudi
- Pharmaceutical Candidate Optimization, Biocon Bristol-Myers Squibb Research & Development Center (BBRC), Syngene International Limited, Bangalore, India
| | - Srikanth K Sridhar
- Pharmaceutical Candidate Optimization, Biocon Bristol-Myers Squibb Research & Development Center (BBRC), Syngene International Limited, Bangalore, India
| | - Raja Reddy Kallem
- School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, Texas, USA
| | - Punit Marathe
- Pharmaceutical Candidate Optimization, Metabolism and Pharmacokinetics, Bristol-Myers Squibb, Princeton, NJ, USA
| | - Sandhya Mandlekar
- Pharmaceutical Candidate Optimization, Biocon Bristol-Myers Squibb Research & Development Center (BBRC), Bristol-Myers Squibb India Ltd, Bangalore, India
| |
Collapse
|
45
|
Abstract
Transport of thyroid hormone (TH) across the plasma membrane is essential for intracellular TH metabolism and action, and this is mediated by specific transporter proteins. During the last two decades several transporters capable of transporting TH have been identified, including monocarboxylate transporter 8 (MCT8), MCT10 and organic anion transporting polypeptide 1C1 (OATP1C1). In particular MCT8 and OATP1C1 are important for the regulation of local TH activity in the brain and thus for brain development. MCT8 is a protein containing 12 transmembrane domains, and is encoded by the SLC16A2 gene located on the X chromosome. It facilitates both TH uptake and efflux across the cell membrane. Male subjects with hemizygous mutations in MCT8 are afflicted with severe intellectual and motor disability, also known as the Allan-Herndon-Dudley syndrome (AHDS), which goes together with low serum T4 and high T3 levels. This review concerns molecular and clinical aspects of MCT8 function.
Collapse
Affiliation(s)
- Stefan Groeneweg
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands.
| | - W Edward Visser
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands.
| | - Theo J Visser
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands.
| |
Collapse
|
46
|
Hülsmann S, Hagos L, Heuer H, Schnell C. Limitations of Sulforhodamine 101 for Brain Imaging. Front Cell Neurosci 2017; 11:44. [PMID: 28293173 PMCID: PMC5328990 DOI: 10.3389/fncel.2017.00044] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 02/09/2017] [Indexed: 11/19/2022] Open
Abstract
Since 2004, the red fluorescent dye Sulforhodamine 101 (SR101) has been boosting the functional analysis of astrocytes in a functional environment in an unprecedented way. However, two major limitations have been challenging the usefulness of this tool for cellular imaging: (i) SR101 is not as specific for astrocytes as previously reported; and (ii) discoveries of severe excitatory side effects of SR101 are bearing the risk of unwanted alteration of the system of interest. In this article, we summarize the current knowledge about SR101-labeling protocols and discuss the problems that arise from varying of the staining protocols. Furthermore, we provide a testable hypothesis for the observed hyper-excitability that can be observed when using SR101.
Collapse
Affiliation(s)
- Swen Hülsmann
- Clinic for Anesthesiology, University Hospital GöttingenGöttingen, Germany; DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB)Göttingen, Germany
| | - Liya Hagos
- Clinic for Anesthesiology, University Hospital GöttingenGöttingen, Germany; DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB)Göttingen, Germany
| | - Heike Heuer
- Leibniz-Institut für Umweltmedizinische Forschung GmbH Düsseldorf, Germany
| | - Christian Schnell
- DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB) Göttingen, Germany
| |
Collapse
|
47
|
Visser TJ. Thyroid hormone transport across the placenta. ANNALES D'ENDOCRINOLOGIE 2016; 77:680-683. [PMID: 27659266 DOI: 10.1016/j.ando.2016.07.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Accepted: 07/17/2016] [Indexed: 11/24/2022]
Affiliation(s)
- Theo J Visser
- Department of Internal Medicine, Erasmus University Medical Center, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands.
| |
Collapse
|
48
|
Henning Y, Szafranski K. Age-Dependent Changes of Monocarboxylate Transporter 8 Availability in the Postnatal Murine Retina. Front Cell Neurosci 2016; 10:205. [PMID: 27616981 PMCID: PMC4999454 DOI: 10.3389/fncel.2016.00205] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 08/15/2016] [Indexed: 12/12/2022] Open
Abstract
The thyroid hormones (TH) triiodothyronine (T3) and its prohormone thyroxine (T4) are crucial for retinal development and function, and increasing evidence points at TH dysregulation as a cause for retinal degenerative diseases. Thus, precise regulation of retinal TH supply is required for proper retinal function, but knowledge on these mechanisms is still fragmentary. Several transmembrane transporters have been described as key regulators of TH availability in target tissues of which the monocarboxylate transporter 8 (MCT8), a high affinity transporter for T4 and T3, plays an essential role in the central nervous system. Moreover, in the embryonic chicken retina, MCT8 is highly expressed, but the postnatal availability of MCT8 in the mammalian retina was not reported to date. In the present study, spatiotemporal retinal MCT8 availability was examined in mice of different age. For this purpose, we quantified expression levels of Mct8 via Real-Time Reverse-Transcriptase PCR in mouse eyecups (C57BL/6) of juvenile and adult age groups. Additionally, age-dependent MCT8 protein levels were quantified via Western blotting and localized via immunofluorescence confocal microscopy. While no difference in Mct8 expression levels could be detected between age groups, MCT8 protein levels in juvenile animals were about two times higher than in adult animals based on Western blot analyses. Immunohistochemical analyses showed that MCT8 immunoreactivity in the eyecup was restricted to the retina and the retinal pigment epithelium. In juvenile mice, MCT8 was broadly observed along the apical membrane of the retinal pigment epithelium, tightly surrounding photoreceptor outer segments. Distinct immunopositive staining was also detected in the inner nuclear layer and the ganglion cell layer. However, in adult specimens, immunoreactivity visibly declined in all layers, which was in line with Western blot analyses. Since MCT8 was abundantly present in juvenile and about twofold lower in adult retinae, our findings suggest a pivotal role of MCT8 especially during postnatal maturation. The present study provides novel insights into age-dependent retinal TH supply, which might help to understand different aspects regarding retinal development, function, and disorders.
Collapse
Affiliation(s)
- Yoshiyuki Henning
- Department of General Zoology, Faculty of Biology, University of Duisburg-Essen Essen, Germany
| | - Karol Szafranski
- Genome Analysis, Leibniz Institute on Aging - Fritz Lipmann Institute Jena, Germany
| |
Collapse
|
49
|
Nałęcz KA. Solute Carriers in the Blood–Brain Barier: Safety in Abundance. Neurochem Res 2016; 42:795-809. [DOI: 10.1007/s11064-016-2030-x] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 07/29/2016] [Accepted: 08/02/2016] [Indexed: 12/22/2022]
|
50
|
Johannes J, Braun D, Kinne A, Rathmann D, Köhrle J, Schweizer U. Few Amino Acid Exchanges Expand the Substrate Spectrum of Monocarboxylate Transporter 10. Mol Endocrinol 2016; 30:796-808. [PMID: 27244477 PMCID: PMC5426580 DOI: 10.1210/me.2016-1037] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 05/24/2016] [Indexed: 02/07/2023] Open
Abstract
Monocarboxylate transporters (MCTs) belong to the SLC16 family within the major facilitator superfamily of transmembrane transporters. MCT8 is a thyroid hormone transporter mutated in the Allan-Herndon-Dudley syndrome, a severe psychomotor retardation syndrome. MCT10 is closely related to MCT8 and is known as T-type amino acid transporter. Both transporters mediate T3 transport, but although MCT8 also transports rT3 and T4, these compounds are not efficiently transported by MCT10, which, in contrast, transports aromatic amino acids. Based on the 58% amino acid identity within the transmembrane regions among MCT8 and MCT10, we reasoned that substrate specificity may be primarily determined by a small number of amino acid differences between MCT8 and MCT10 along the substrate translocation channel. Inspecting the homology model of MCT8 and a structure-guided alignment between both proteins, we selected 8 amino acid positions and prepared chimeric MCT10 proteins with selected amino acids changed to the corresponding amino acids in MCT8. The MCT10 mutant harboring 8 amino acid substitutions was stably expressed in Madin-Darby canine kidney 1 cells and found to exhibit T4 transport activity. We then successively reduced the number of amino acid substitutions and eventually identified a minimal set of 2-3 amino acid exchanges which were sufficient to allow T4 transport. The resulting MCT10 chimeras exhibited KM values for T4 similar to MCT8 but transported T4 at a slower rate. The acquisition of T4 transport by MCT10 was associated with complete loss of the capacity to transport Phe, when Tyr184 was mutated to Phe.
Collapse
Affiliation(s)
- Jörg Johannes
- Institut für Biochemie und Molekularbiologie (J.J., D.B., U.S.), Rheinische Friedrich-Wilhelms-Universität, 53115 Bonn, Germany; and Institut für Experimentelle Endokrinologie (J.J., A.K., D.R., J.K.), Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
| | - Doreen Braun
- Institut für Biochemie und Molekularbiologie (J.J., D.B., U.S.), Rheinische Friedrich-Wilhelms-Universität, 53115 Bonn, Germany; and Institut für Experimentelle Endokrinologie (J.J., A.K., D.R., J.K.), Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
| | - Anita Kinne
- Institut für Biochemie und Molekularbiologie (J.J., D.B., U.S.), Rheinische Friedrich-Wilhelms-Universität, 53115 Bonn, Germany; and Institut für Experimentelle Endokrinologie (J.J., A.K., D.R., J.K.), Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
| | - Daniel Rathmann
- Institut für Biochemie und Molekularbiologie (J.J., D.B., U.S.), Rheinische Friedrich-Wilhelms-Universität, 53115 Bonn, Germany; and Institut für Experimentelle Endokrinologie (J.J., A.K., D.R., J.K.), Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
| | - Josef Köhrle
- Institut für Biochemie und Molekularbiologie (J.J., D.B., U.S.), Rheinische Friedrich-Wilhelms-Universität, 53115 Bonn, Germany; and Institut für Experimentelle Endokrinologie (J.J., A.K., D.R., J.K.), Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
| | - Ulrich Schweizer
- Institut für Biochemie und Molekularbiologie (J.J., D.B., U.S.), Rheinische Friedrich-Wilhelms-Universität, 53115 Bonn, Germany; and Institut für Experimentelle Endokrinologie (J.J., A.K., D.R., J.K.), Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
| |
Collapse
|