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Karbownik-Lewińska M, Stępniak J, Iwan P, Lewiński A. Iodine as a potential endocrine disruptor-a role of oxidative stress. Endocrine 2022; 78:219-240. [PMID: 35726078 PMCID: PMC9584999 DOI: 10.1007/s12020-022-03107-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 06/02/2022] [Indexed: 12/19/2022]
Abstract
PURPOSE Iodine is an essential micronutrient required for thyroid hormone biosynthesis. However, overtreatment with iodine can unfavorably affect thyroid physiology. The aim of this review is to present the evidence that iodine-when in excess-can interfere with thyroid hormone synthesis and, therefore, can act as a potential endocrine-disrupting chemical (EDC), and that this action, as well as other abnormalities in the thyroid, occurs-at least partially-via oxidative stress. METHODS We reviewed published studies on iodine as a potential EDC, with particular emphasis on the phenomenon of oxidative stress. RESULTS This paper summarizes current knowledge on iodine excess in the context of its properties as an EDC and its effects on oxidative processes. CONCLUSION Iodine does fulfill the criteria of an EDC because it is an exogenous chemical that interferes-when in excess-with thyroid hormone synthesis. However, this statement cannot change general rules regarding iodine supply, which means that iodine deficiency should be still eliminated worldwide and, at the same time, iodine excess should be avoided. Universal awareness that iodine is a potential EDC would make consumers more careful regarding their diet and what they supplement in tablets, and-what is of great importance-it would make caregivers choose iodine-containing medications (or other chemicals) more prudently. It should be stressed that compared to iodine deficiency, iodine in excess (acting either as a potential EDC or via other mechanisms) is much less harmful in such a sense that it affects only a small percentage of sensitive individuals, whereas the former affects whole populations; therefore, it causes endemic consequences.
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Affiliation(s)
- Małgorzata Karbownik-Lewińska
- Department of Oncological Endocrinology, Medical University of Lodz, 90-752, Lodz, Poland.
- Polish Mother's Memorial Hospital-Research Institute, 93-338, Lodz, Poland.
| | - Jan Stępniak
- Department of Oncological Endocrinology, Medical University of Lodz, 90-752, Lodz, Poland
| | - Paulina Iwan
- Department of Oncological Endocrinology, Medical University of Lodz, 90-752, Lodz, Poland
| | - Andrzej Lewiński
- Polish Mother's Memorial Hospital-Research Institute, 93-338, Lodz, Poland
- Department of Endocrinology and Metabolic Diseases, Medical University of Lodz, 93-338, Lodz, Poland
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Serrano-Nascimento C, Nicola JP, Teixeira SDS, Poyares LL, Lellis-Santos C, Bordin S, Masini-Repiso AM, Nunes MT. Excess iodide downregulates Na(+)/I(-) symporter gene transcription through activation of PI3K/Akt pathway. Mol Cell Endocrinol 2016; 426:73-90. [PMID: 26872612 DOI: 10.1016/j.mce.2016.02.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 02/08/2016] [Accepted: 02/08/2016] [Indexed: 12/19/2022]
Abstract
Transcriptional mechanisms associated with iodide-induced downregulation of NIS expression remain uncertain. Here, we further analyzed the transcriptional regulation of NIS gene expression by excess iodide using PCCl3 cells. NIS promoter activity was reduced in cells treated for 12-24 h with 10(-5) to 10(-3) M NaI. Site-directed mutagenesis of Pax8 and NF-κB cis-acting elements abrogated the iodide-induced NIS transcription repression. Indeed, excess iodide (10(-3) M) excluded Pax8 from the nucleus, decreased p65 total expression and reduced their transcriptional activity. Importantly, p65-Pax8 physical interaction and binding to NIS upstream enhancer were reduced upon iodide treatment. PI3K/Akt pathway activation by iodide-induced ROS production is involved in the transcriptional repression of NIS expression. In conclusion, the results indicated that excess iodide transcriptionally represses NIS gene expression through the impairment of Pax8 and p65 transcriptional activity. Furthermore, the data presented herein described novel roles for PI3K/Akt signaling pathway and oxidative status in the thyroid autoregulatory phenomenon.
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Affiliation(s)
- Caroline Serrano-Nascimento
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
| | - Juan Pablo Nicola
- Centro de Investigaciones en Bioquímica Clínica e Inmunología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina.
| | - Silvania da Silva Teixeira
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
| | - Leonice Lourenço Poyares
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
| | - Camilo Lellis-Santos
- Department of Biological Sciences, Institute of Environmental, Chemical and Pharmaceutical Sciences, Federal University of São Paulo, Brazil.
| | - Silvana Bordin
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
| | - Ana Maria Masini-Repiso
- Centro de Investigaciones en Bioquímica Clínica e Inmunología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina.
| | - Maria Tereza Nunes
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
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Thomasz L, Coulonval K, Salvarredi L, Oglio R, Fusco A, Rossich L, Pisarev MA, Roger PP, Juvenal GJ. Inhibitory effects of 2-iodohexadecanal on FRTL-5 thyroid cells proliferation. Mol Cell Endocrinol 2015; 404:123-31. [PMID: 25657048 DOI: 10.1016/j.mce.2015.01.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 01/14/2015] [Accepted: 01/26/2015] [Indexed: 10/24/2022]
Abstract
UNLABELLED Although thyroid gland function is mainly under the control of pituitary TSH, other factors, such as iodine, play a role in this process. The thyroid is capable of producing different iodolipids such as 6-iodo-deltalactone and 2-iodohexadecanal (2-IHDA). It was shown that these iodolipids mimic some of the inhibitory effects of excess iodide on several thyroid parameters. OBJECTIVES To study the effect of 2-IHDA on cell proliferation and apoptosis in FRTL-5 cells. RESULTS FRTL-5 cells were grown in the presence of TSH and treated with increasing concentrations of KI and 2-IHDA (0.5, 5, 10 and 33 µM) for 24, 48 and 72 h. Whereas KI inhibited cell proliferation only at 33 µM after 72 h of treatment, 2-IHDA inhibited in a time and concentration dependent manner. Analysis of cell cycle by flow cytometric DNA analysis revealed an accumulation of cells in G1 phase induced by 2-IHDA. The expression of cyclin A, cyclin D1 and cyclin D3 were reduced after treatment with 2-IHDA whereas CDK4 and CDK6 proteins were not modified. 2-IHDA induced a dynamic change in cytoplasmic to nuclear accumulation of p21 and p27 causing these proteins to be accumulated mostly in the nucleus. We also observed evidence of a pro-apoptotic effect of 2-IHDA at highest concentrations. No significant effect of KI was observed. CONCLUSION These results suggest that the inhibitory effects of 2-IHDA on FRTL-5 thyroid cell proliferation are mediated by cell cycle arrest in G1/S phase and cell death by apoptosis.
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Affiliation(s)
- Lisa Thomasz
- Nuclear Biochemistry Division, National Atomic Energy Commission, Buenos Aires, Argentina
| | - Katia Coulonval
- I.R.I.B.H.M., Université Libre de Bruxelles, Bruxelles, Belgium
| | - Leonardo Salvarredi
- Nuclear Biochemistry Division, National Atomic Energy Commission, Buenos Aires, Argentina
| | - Romina Oglio
- Nuclear Biochemistry Division, National Atomic Energy Commission, Buenos Aires, Argentina
| | - Alfredo Fusco
- IEOS, Università degli Studi di Napoli "Federico II", Naples, Italy
| | - Luciano Rossich
- Nuclear Biochemistry Division, National Atomic Energy Commission, Buenos Aires, Argentina
| | - Mario A Pisarev
- Nuclear Biochemistry Division, National Atomic Energy Commission, Buenos Aires, Argentina; Human Biochemistry, School of Medicine, University of Buenos Aires, Buenos Aires, Argentina
| | - Pierre P Roger
- I.R.I.B.H.M., Université Libre de Bruxelles, Bruxelles, Belgium
| | - Guillermo J Juvenal
- Nuclear Biochemistry Division, National Atomic Energy Commission, Buenos Aires, Argentina.
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Nava-Villalba M, Aceves C. 6-iodolactone, key mediator of antitumoral properties of iodine. Prostaglandins Other Lipid Mediat 2014; 112:27-33. [PMID: 25018052 DOI: 10.1016/j.prostaglandins.2014.07.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 06/20/2014] [Accepted: 07/01/2014] [Indexed: 12/12/2022]
Abstract
An iodinated derivative of arachidonic acid, 5-hydroxy-6-iodo-8,11,14-eicosatrienoic acid, δ-lactone (6-IL) has been implicated as a possible intermediate in the autoregulation of the thyroid gland by iodine. In addition to antiproliferative and apoptotic effects observed in thyrocytes, this iodolipid could also exert similar actions in cells derived from extrathyroidal tissues like mammary gland, prostate, colon, or the nervous system. In mammary cancer (solid tumors or tumor cell lines), 6-IL has been detected after molecular iodine (I2) supplement, and is a potent activator of peroxisome proliferator-activated receptor type gamma (PPARγ). These observations led us to propose I2 supplement as a novel coadjutant therapy which, by inducing differentiation mechanisms, decreases tumor progression and prevents chemoresistance. Some kinds of tumoral cells, in contrast to normal cells, contain high concentrations of arachidonic acid, making the I2 supplement a potential "magic bullet" that enables local, specific production of 6-IL, which then exerts antineoplastic actions with minimal deleterious effects on normal tissues.
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Affiliation(s)
- Mario Nava-Villalba
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro, Mexico.
| | - Carmen Aceves
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro, Mexico.
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Portulano C, Paroder-Belenitsky M, Carrasco N. The Na+/I- symporter (NIS): mechanism and medical impact. Endocr Rev 2014; 35:106-49. [PMID: 24311738 PMCID: PMC3895864 DOI: 10.1210/er.2012-1036] [Citation(s) in RCA: 177] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Accepted: 10/11/2013] [Indexed: 12/26/2022]
Abstract
The Na(+)/I(-) symporter (NIS) is the plasma membrane glycoprotein that mediates active I(-) transport in the thyroid and other tissues, such as salivary glands, stomach, lactating breast, and small intestine. In the thyroid, NIS-mediated I(-) uptake plays a key role as the first step in the biosynthesis of the thyroid hormones, of which iodine is an essential constituent. These hormones are crucial for the development of the central nervous system and the lungs in the fetus and the newborn and for intermediary metabolism at all ages. Since the cloning of NIS in 1996, NIS research has become a major field of inquiry, with considerable impact on many basic and translational areas. In this article, we review the most recent findings on NIS, I(-) homeostasis, and related topics and place them in historical context. Among many other issues, we discuss the current outlook on iodide deficiency disorders, the present stage of understanding of the structure/function properties of NIS, information gleaned from the characterization of I(-) transport deficiency-causing NIS mutations, insights derived from the newly reported crystal structures of prokaryotic transporters and 3-dimensional homology modeling, and the novel discovery that NIS transports different substrates with different stoichiometries. A review of NIS regulatory mechanisms is provided, including a newly discovered one involving a K(+) channel that is required for NIS function in the thyroid. We also cover current and potential clinical applications of NIS, such as its central role in the treatment of thyroid cancer, its promising use as a reporter gene in imaging and diagnostic procedures, and the latest studies on NIS gene transfer aimed at extending radioiodide treatment to extrathyroidal cancers, including those involving specially engineered NIS molecules.
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Affiliation(s)
- Carla Portulano
- Department of Molecular and Cellular Physiology (C.P., N.C.), Yale University School of Medicine, New Haven, Connecticut 06510; and Department of Molecular Pharmacology (M.P.-B.), Albert Einstein College of Medicine, Bronx, New York 10469
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6
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Abstract
This review, with 290 references, presents the fascinating area of iodinated natural products over the past hundred years for the first time.
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Affiliation(s)
- Lishu Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica/RNAM Center for Marine Microbiology
- South China Sea Institute of Oceanology
- Chinese Academy of Sciences
- Guangzhou 510301, China
- Jilin Provincial Academy of Chinese Medicine Sciences
| | - Xuefeng Zhou
- Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica/RNAM Center for Marine Microbiology
- South China Sea Institute of Oceanology
- Chinese Academy of Sciences
- Guangzhou 510301, China
| | - Mangaladoss Fredimoses
- Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica/RNAM Center for Marine Microbiology
- South China Sea Institute of Oceanology
- Chinese Academy of Sciences
- Guangzhou 510301, China
| | - Shengrong Liao
- Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica/RNAM Center for Marine Microbiology
- South China Sea Institute of Oceanology
- Chinese Academy of Sciences
- Guangzhou 510301, China
| | - Yonghong Liu
- Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica/RNAM Center for Marine Microbiology
- South China Sea Institute of Oceanology
- Chinese Academy of Sciences
- Guangzhou 510301, China
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Lima Gonçalves CF, de Souza dos Santos MC, Ginabreda MG, Soares Fortunato R, Pires de Carvalho D, Freitas Ferreira AC. Flavonoid rutin increases thyroid iodide uptake in rats. PLoS One 2013; 8:e73908. [PMID: 24023911 PMCID: PMC3762709 DOI: 10.1371/journal.pone.0073908] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 07/25/2013] [Indexed: 11/19/2022] Open
Abstract
Thyroid iodide uptake through the sodium-iodide symporter (NIS) is not only an essential step for thyroid hormones biosynthesis, but also fundamental for the diagnosis and treatment of different thyroid diseases. However, part of patients with thyroid cancer is refractory to radioiodine therapy, due to reduced ability to uptake iodide, which greatly reduces the chances of survival. Therefore, compounds able to increase thyroid iodide uptake are of great interest. It has been shown that some flavonoids are able to increase iodide uptake and NIS expression in vitro, however, data in vivo are lacking. Flavonoids are polyhydroxyphenolic compounds, found in vegetables present in human diet, and have been shown not only to modulate NIS, but also thyroperoxidase (TPO), the key enzyme in thyroid hormones biosynthesis, besides having antiproliferative effect in thyroid cancer cell lines. Therefore, we aimed to evaluate the effect of some flavonoids on thyroid iodide uptake in Wistar rats in vivo. Among the flavonoids tested, rutin was the only one able to increase thyroid iodide uptake, so we decided to evaluate the effect of this flavonoid on some aspects of thyroid hormones synthesis and metabolism. Rutin led to a slight reduction of serum T4 and T3 without changes in serum thyrotropin (TSH), and significantly increased hypothalamic, pituitary and brown adipose tissue type 2 deiodinase and decreased liver type 1 deiodinase activities. Moreover, rutin treatment increased thyroid iodide uptake probably due to the increment of NIS expression, which might be secondary to increased response to TSH, since TSH receptor expression was increased. Thus, rutin might be useful as an adjuvant in radioiodine therapy, since this flavonoid increased thyroid iodide uptake without greatly affecting thyroid function.
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Affiliation(s)
- Carlos Frederico Lima Gonçalves
- Laboratório de Fisiologia Endócrina Doris Rosenthal, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil
| | - Maria Carolina de Souza dos Santos
- Laboratório de Fisiologia Endócrina Doris Rosenthal, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil
| | - Maria Gloria Ginabreda
- Laboratório de Fisiologia Endócrina Doris Rosenthal, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil
| | - Rodrigo Soares Fortunato
- Laboratório de Fisiologia Endócrina Doris Rosenthal, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil
| | - Denise Pires de Carvalho
- Laboratório de Fisiologia Endócrina Doris Rosenthal, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil
| | - Andrea Claudia Freitas Ferreira
- Laboratório de Fisiologia Endócrina Doris Rosenthal, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil
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Colin IM, Denef JF, Lengelé B, Many MC, Gérard AC. Recent insights into the cell biology of thyroid angiofollicular units. Endocr Rev 2013; 34:209-38. [PMID: 23349248 PMCID: PMC3610675 DOI: 10.1210/er.2012-1015] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 11/07/2012] [Indexed: 01/06/2023]
Abstract
In thyrocytes, cell polarity is of crucial importance for proper thyroid function. Many intrinsic mechanisms of self-regulation control how the key players involved in thyroid hormone (TH) biosynthesis interact in apical microvilli, so that hazardous biochemical processes may occur without detriment to the cell. In some pathological conditions, this enzymatic complex is disrupted, with some components abnormally activated into the cytoplasm, which can lead to further morphological and functional breakdown. When iodine intake is altered, autoregulatory mechanisms outside the thyrocytes are activated. They involve adjacent capillaries that, together with thyrocytes, form the angiofollicular units (AFUs) that can be considered as the functional and morphological units of the thyroid. In response to iodine shortage, a rapid expansion of the microvasculature occurs, which, in addition to nutrients and oxygen, optimizes iodide supply. These changes are triggered by angiogenic signals released from thyrocytes via a reactive oxygen species/hypoxia-inducible factor/vascular endothelial growth factor pathway. When intra- and extrathyrocyte autoregulation fails, other forms of adaptation arise, such as euthyroid goiters. From onset, goiters are morphologically and functionally heterogeneous due to the polyclonal nature of the cells, with nodules distributed around areas of quiescent AFUs containing globules of compact thyroglobulin (Tg) and surrounded by a hypotrophic microvasculature. Upon TSH stimulation, quiescent AFUs are activated with Tg globules undergoing fragmentation into soluble Tg, proteins involved in TH biosynthesis being expressed and the local microvascular network extending. Over time and depending on physiological needs, AFUs may undergo repetitive phases of high, moderate, or low cell and tissue activity, which may ultimately culminate in multinodular goiters.
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Affiliation(s)
- Ides M Colin
- Pôle de Morphologie, Institut de Recherche Expérimentale et Clinique, Secteur des Sciences de la Santé, Université Catholique de Louvain (UCL), UCL-5251, 52 Avenue E. Mounier, B-1200, Bruxelles, Belgium.
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Degrelle S, Guibourdenche J, Galland F, Bidart J, Fournier T, Evain-Brion D. Iodide transporters expression in early human invasive trophoblast. Placenta 2013; 34:29-34. [DOI: 10.1016/j.placenta.2012.11.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Revised: 10/09/2012] [Accepted: 11/01/2012] [Indexed: 11/17/2022]
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Massart C, Hoste C, Virion A, Ruf J, Dumont JE, Van Sande J. Cell biology of H2O2 generation in the thyroid: investigation of the control of dual oxidases (DUOX) activity in intact ex vivo thyroid tissue and cell lines. Mol Cell Endocrinol 2011; 343:32-44. [PMID: 21683758 DOI: 10.1016/j.mce.2011.05.047] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2011] [Revised: 05/06/2011] [Accepted: 05/31/2011] [Indexed: 10/18/2022]
Abstract
H2O2 generation by dual oxidase (DUOX) at the apex of thyroid cells is the limiting factor in the oxidation of iodide and the synthesis of thyroid hormones. Its characteristics have been investigated using different in vitro models, from the most physiological thyroid slices to the particulate fraction isolated from transfected DUOX expressing CHO cells. Comparison of the models shows that some positive controls are thyroid specific (TSH) or require the substructure of the in vivo cells (MβCD). Other controls apply to all intact cell models such as the stimulation of the PIP(2) phospholipase C pathway by ATP acting on purinergic receptors, the activation of the Gq protein downstream (NaF), or surrogates of the intracellular signals generated by this cascade (phorbol esters for protein kinase C, Ca(++) ionophore for Ca(++)). Still, other controls, exerted by intracellular Ca(++) or its substitute Mn(++), the intracellular pH, or arachidonate bear directly on the enzyme. Iodide acts at the apical membrane of the cell through an oxidized form, presumably iodohexadecanal. Cooling of the cells to 22°C blocks the activation of the PIP(2) phospholipase C cascade. All these effects are reversible. Their kinetics and concentration-effect characteristics have been defined in the four models. A general scheme of the thyroid signaling pathways regulating this metabolism is proposed. The probes characterized could be applied to other H2O2 producing cells and to pathological material.
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Affiliation(s)
- C Massart
- Institute of Interdisciplinary Research (IRIBHM), University of Brussels, Campus Erasme, Route de Lennik 808, B 1070 Brussels, Belgium
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Thomasz L, Oglio R, Dagrosa MA, Krawiec L, Pisarev MA, Juvenal GJ. 6 Iodo-delta-lactone reproduces many but not all the effects of iodide. Mol Cell Endocrinol 2010; 323:161-6. [PMID: 20302908 DOI: 10.1016/j.mce.2010.03.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Revised: 03/09/2010] [Accepted: 03/10/2010] [Indexed: 11/30/2022]
Abstract
BACKGROUND Iodide has direct effects on thyroid function. Several iodinated lipids are biosynthesized by the thyroid and they were postulated as intermediaries in the action of iodide. Among them 6 iodo-delta-lactone (IL-delta) has been identified and proposed to play a role in thyroid autoregulation. The aim of this study was to compare the effect of iodide and IL-delta on several thyroid parameters. METHODS Thyroid bovine follicles were incubated with the different compounds during three days. RESULTS KI and IL-delta inhibited iodide uptake, total protein and Tg synthesis but only KI had an effect on NIS and Tg mRNAs levels. Both compounds inhibited Na+/K+ ATPase and deoxy-glucose uptake. As PAX 8, FOXE 1 and TITF1 are involved in the regulation of thyroid specific genes their mRNA levels were measured. While iodide inhibited the expression of the first two, the expression of TITF1 was stimulated by iodide and IL-delta had no effect on these parameters. CONCLUSION These findings indicate that IL-delta reproduces some but not all the effects of excess iodide. These observations apply for higher micromolar concentrations of iodide while no such effects could be demonstrated at nanomolar iodide concentrations.
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Affiliation(s)
- Lisa Thomasz
- Nuclear Biochemistry Division, CNEA, Av. Del Libertador 8250, Argentine National Atomic Energy Commission, Buenos Aires 1429, Argentina
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13
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Dayem M, Navarro V, Marsault R, Darcourt J, Lindenthal S, Pourcher T. From the molecular characterization of iodide transporters to the prevention of radioactive iodide exposure. Biochimie 2006; 88:1793-806. [PMID: 16905238 DOI: 10.1016/j.biochi.2006.07.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2006] [Accepted: 07/19/2006] [Indexed: 12/23/2022]
Abstract
In the event of a nuclear reactor accident, the major public health risk will likely result from the release and dispersion of volatile radio-iodines. Upon body exposure and food ingestion, these radio-iodines are concentrated in the thyroid, resulting in substantial thyroidal irradiation and accordingly causing thyroid cancers. Stable potassium iodide (KI) effectively blocks thyroid iodine uptake and is thus used in iodide prophylaxis for reactor accidents. The efficiency of KI is directly related to the physiological inhibition of the thyroid function in the presence of high plasma iodide concentrations. This regulation is called the Wolff-Chaikoff effect. However, to be fully effective, KI should be administered shortly before or immediately after radioiodine exposure. If KI is provided only several hours after exposure, it will elicit the opposite effect e.g. lead to an increase in the thyroid irradiation dose. To date, clear evaluation of the benefit and the potential toxicity of KI administration remain difficult, and additional data are needed. We outline in this review the molecular characterization of KI-induced regulation of the thyroid function. Significant advances in the knowledge of the iodide transport mechanisms and thyroid physiology have been made. Recently developed molecular tools should help clarify iodide metabolism and the Wolff-Chaikoff effect. The major goals are clarifying the factors which increase thyroid cancer risk after a reactor accident and improving the KI administration protocol. These will ultimately lead to the development of novel strategies to decrease thyroid irradiation after radio-iodine exposure.
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Affiliation(s)
- M Dayem
- Unité TIRO (Transporter in Imaging and Radiotherapy in Oncology), Commissariat à l'énergie atomique DSV-DIEP-SBTN, School of Medicine, University of Nice Sophia Antipolis, 28, avenue de Valombrose, 06107 Nice cedex, France
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Le symporteur sodium/iodure : données récentes et perspectives thérapeutiques. ACTA ACUST UNITED AC 2005; 53:174-82. [DOI: 10.1016/j.patbio.2004.06.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2003] [Indexed: 11/20/2022]
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Abstract
A randomized, double-blind, placebo-controlled, multicenter clinical trial was conducted with 111 otherwise healthy euthyroid women with a history of breast pain. Patients had to document moderate or severe breast pain by recording a score > or =5 on a visual analog scale (VAS) of pain for > or =6 days per cycle and had to present with fibrosis involving at least 25% of both breast surfaces. Subjects could not be effectively treated with more conservative measures such as local heat or nonprescription analgesics. There was not a statistically significant difference in the dropout rate for patients on placebo (11.8%), 1.5 mg/day (31.3%), 3.0 mg/day (18.4%), or 6.0 mg/day (25%) of molecular iodine for 6 months. Physicians assessed breast pain, tenderness, and nodularity each cycle; patients assessed breast pain and tenderness with the Lewin breast pain scale at 3-month intervals and with a VAS at each cycle. A statistically significant improvement (p < 0.01) associated with dose was observed in the Lewin overall pain scale for all treated groups compared to placebo. Reductions in all three physician assessments were observed in patients after 5 months of therapy in the 3.0 mg/day (7/28; 25%) and 6.0 mg/day (15/27; 18.5%) treatment groups, but not the 1.5 mg/day or placebo group. Patients recorded statistically significant decreases in pain by month 3 in the 3.0 and 6.0 mg/day treatment groups, but not the 1.5 mg/day or placebo group; more than 50% of the 6.0 mg/day treatment group recorded a clinically significant reduction in overall pain. All doses were associated with an acceptable safety profile. No dose-related increase in any adverse event was observed.
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Affiliation(s)
- Jack H Kessler
- Symbollon Pharmaceuticals, Inc., Framingham, Massachusetts 01702, USA. Jack_
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16
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Affiliation(s)
- Orsolya Dohán
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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Dohán O, De la Vieja A, Paroder V, Riedel C, Artani M, Reed M, Ginter CS, Carrasco N. The sodium/iodide Symporter (NIS): characterization, regulation, and medical significance. Endocr Rev 2003; 24:48-77. [PMID: 12588808 DOI: 10.1210/er.2001-0029] [Citation(s) in RCA: 534] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The Na(+)/I(-) symporter (NIS) is an integral plasma membrane glycoprotein that mediates active I(-) transport into the thyroid follicular cells, the first step in thyroid hormone biosynthesis. NIS-mediated thyroidal I(-) transport from the bloodstream to the colloid is a vectorial process made possible by the selective targeting of NIS to the basolateral membrane. NIS also mediates active I(-) transport in other tissues, including salivary glands, gastric mucosa, and lactating mammary gland, in which it translocates I(-) into the milk for thyroid hormone biosynthesis by the nursing newborn. NIS provides the basis for the effective diagnostic and therapeutic management of thyroid cancer and its metastases with radioiodide. NIS research has proceeded at an astounding pace after the 1996 isolation of the rat NIS cDNA, comprising the elucidation of NIS secondary structure and topology, biogenesis and posttranslational modifications, transcriptional and posttranscriptional regulation, electrophysiological analysis, isolation of the human NIS cDNA, and determination of the human NIS genomic organization. Clinically related topics include the analysis of congenital I(-) transport defect-causing NIS mutations and the role of NIS in thyroid cancer. NIS has been transduced into various kinds of cancer cells to render them susceptible to destruction with radioiodide. Most dramatically, the discovery of endogenous NIS expression in more than 80% of human breast cancer samples has raised the possibility that radioiodide may be a valuable novel tool in breast cancer diagnosis and treatment.
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Affiliation(s)
- Orsolya Dohán
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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Cauvi D, Nlend MC, Venot N, Chabaud O. Sulfate transport in porcine thyroid cells. Effects of thyrotropin and iodide. Am J Physiol Endocrinol Metab 2001; 281:E440-8. [PMID: 11500298 DOI: 10.1152/ajpendo.2001.281.3.e440] [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] [Indexed: 11/22/2022]
Abstract
In porcine thyroid cells, thyroglobulin sulfation is controlled by thyrotropin (TSH) and iodide, which contribute to regulating the intracellular sulfate concentration, as we previously established. Here, we studied the transport of sulfate and its regulation by these two effectors. Kinetic studies were performed after [(35)S]sulfate was added to either the basal or apical medium of cell monolayers cultured without any effectors, or with TSH with or without iodide. The basolateral uptake rates were about tenfold higher than the apical uptake rates. TSH increased the basolateral and apical uptake values (by 24 and 9%, respectively, compared with unstimulated cells), and iodide inhibited these effects of TSH. On the basis of results of the pulse-chase experiments, the basolateral and apical effluxes appeared to be well balanced in unstimulated cells and in cells stimulated by both TSH and iodide: approximately 40-50% of the intracellular radioactivity was released into each medium, whereas in the absence of iodide, 70% of the intracellular radioactivity was released on the basolateral side. The rates of transepithelial sulfate transport were increased by TSH compared with unstimulated cells, and these effects decreased in response to iodide. These results suggest that TSH and iodide may each control the sulfate transport process on two sides of the polarized cells, and that the absence of iodide in the TSH-stimulated cells probably results in an unbalanced state of sulfate transport.
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Affiliation(s)
- D Cauvi
- Institut National de la Santé et de la Recherche Médicale U555, Faculté de Médecine, Université de la Méditerranée, 27 Bd Jean Moulin, 13385 Marseille cedex 05, France
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19
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Spitzweg C, Dutton CM, Castro MR, Bergert ER, Goellner JR, Heufelder AE, Morris JC. Expression of the sodium iodide symporter in human kidney. Kidney Int 2001; 59:1013-23. [PMID: 11231356 DOI: 10.1046/j.1523-1755.2001.0590031013.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND The human sodium iodide symporter (hNIS) is a transmembrane protein that mediates the active transport of iodide in the thyroid gland. Following cloning of NIS, NIS expression has been detected in a broad range of nonthyroidal tissues, suggesting that iodide transport in these tissues is conferred by the expression of functional NIS protein. METHODS The aim of this study was to examine functional hNIS expression in kidney by reverse transcription-polymerase chain reaction (RT-PCR), ribonuclease protection assay (RPA), immunohistochemistry, and Western blot analysis accompanied by iodide accumulation studies in kidney cells. RESULTS Using a pair of full-length hNIS-specific oligonucleotide primers, RT-PCR followed by Southern hybridization revealed hNIS mRNA expression in normal human kidney tissue. The PCR products were subjected to automated sequencing and revealed full identity with the published human thyroid-derived NIS cDNA sequence. Furthermore, positive protected bands indicating the presence of hNIS mRNA were apparent in RPA gel lanes corresponding to human kidney cells as well as Chinese hamster ovary (CHO) cells stably transfected with hNIS cDNA and Graves' thyroid tissue. Immunohistochemical analysis of normal human kidney tissue using a mouse monoclonal hNIS-specific antibody showed marked hNIS-specific immunoreactivity confined to tubular cells, while no hNIS-specific immunoreactivity was detected in the glomeruli. NIS protein expression in human kidney cells was further confirmed by Western blot analysis. In addition, accumulation of (125)I was detected in human kidney cells in vitro and was shown to be sodium dependent and sensitive to perchlorate. CONCLUSIONS Functional hNIS expression was demonstrated in the renal tubular system, suggesting that renal iodide transport may be, at least in part, an active process driven by NIS.
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Affiliation(s)
- C Spitzweg
- Department of Endocrinology, Mayo Clinic, Rochester, Minnesota 55905, USA.
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21
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Siegel RD, Lee SL. Toxic nodular goiter. Toxic adenoma and toxic multinodular goiter. Endocrinol Metab Clin North Am 1998; 27:151-68. [PMID: 9534034 DOI: 10.1016/s0889-8529(05)70304-2] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Solitary toxic adenoma and toxic multinodular goiter are very common forms of thyrotoxicosis around the world. Advances in molecular biology and genetics have led to new insights into the pathogenesis of these disorders. Current theories on autonomy in the thyroid are discussed in this article. The therapeutic roles of surgery, radioiodine ablation, and percutaneous ethanol administration also are reviewed.
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Affiliation(s)
- R D Siegel
- Division of Endocrinology, Diabetes, Metabolism and Molecular Medicine, New England Medical Center, Boston, Massachusetts, USA
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22
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Penel C, Gruffat D, Alquier C, Benoliel AM, Chabaud O. Thyrotropin chronically regulates the pool of thyroperoxidase and its intracellular distribution: a quantitative confocal microscopic study. J Cell Physiol 1998; 174:160-9. [PMID: 9428802 DOI: 10.1002/(sici)1097-4652(199802)174:2<160::aid-jcp3>3.0.co;2-m] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The regulation of thyroperoxidase (TPO) expression and of its intracellular distribution was studied in porcine thyroid cells cultured on porous bottom filters. Cells were cultured for 18 days in the absence or in the presence of thyrotropin (TSH) and with or without iodide. Microsomes were purified and analyzed by electrophoresis. TPO was detected by immunoblotting with polyclonal anti-porcine TPO antibodies and quantified by scanning the bands. The amount of TPO was increased 2-fold by TSH. High concentrations of iodide (1-50 microM, added daily) decreased the level of TPO. Confocal microscopy served to determine the intracellular localization of TPO and its quantitative distribution. Intracellular and surface-located TPO was detected by fluorescein-labeled antibodies on saponin-treated cells. Quantitative confocal microscopy showed that TSH increased the total amount of TPO 2-fold as for immunoblotting. The highest amount of TPO was found in the perinuclear area and between the nucleus and the Golgi apparatus. Only 4% of TPO was present on the apical surface and about 1% on the basolateral membrane; the remainder (about 95%) was inside the cells. TSH did not change these relative contents. TSH modified the intracellular distribution of the enzyme, increasing the TPO pool from the perinuclear area to apical membrane. This domain could be a site of storage of TPO. Adding a physiological concentration of iodide (0.5 microM, daily) did not influence the intracellular distribution of TPO. We concluded that chronic TSH stimulation 1) increased 2-fold the pool of TPO but did not change the relative proportion of TPO inside the cells and on the apical surface, and 2) modified the intracellular distribution of vesicular TPO, the major part of which was accumulated in the perinuclear and cytoplasmic area under the subapical domain of the polarized cells.
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Affiliation(s)
- C Penel
- INSERM CJF 93-11-IFR. J. Roche, Faculté de Médecine Nord, Université de la Méditerranée, Marseille, France
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Uyttersprot N, Pelgrims N, Carrasco N, Gervy C, Maenhaut C, Dumont JE, Miot F. Moderate doses of iodide in vivo inhibit cell proliferation and the expression of thyroperoxidase and Na+/I- symporter mRNAs in dog thyroid. Mol Cell Endocrinol 1997; 131:195-203. [PMID: 9296378 DOI: 10.1016/s0303-7207(97)00108-1] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The function and the growth of adult thyroid gland is controlled by the opposite actions of thyrotropin (TSH) and iodide, the main substrate of the gland. Iodide deprivation leads to stimulation of the thyroid, improving the efficiency of iodide transport for hormone biosynthesis. We have investigated cell proliferation and thyroid specific gene expression 24 and 48 h after administering KI to dogs previously treated with goitrogens and perchlorate. In the hypothyroid dogs T3 and T4 serum levels decreased from 53 +/- 4 to < 30 ng/dl and from 1.6 +/- 0.6 to < 1 microg/dl respectively; TSH concentration increased from 0.16 +/- 0.02 to 2.7 +/- 0.4 ng/ml. After a 24 h moderate KI treatment (300 microg KI/dog of +/- 10 kg) serum T3 concentrations rose higher than the initial normal values, while T4 concentrations increased to reach values equivalent to the normal level. The high TSH concentration did not change significantly. The hyperplasia of the chronically stimulated thyroid resulting from goitrogens/NaClO4 treatment was not modified by this short term treatment with KI. In contrast, KI decreased the weight of the total gland and the level of cell proliferation, as determined by the fraction of cells incorporating BrdU. The effect of acute administration of KI on the expression of four major thyroid genes, the TSH receptor (TSHr), thyroglobulin (Tg), thyroperoxidase (TPO), and Na+/I- symporter (NIS) was analyzed by Northern blot. Tg, TPO and NIS mRNA expressions were up-regulated by chronic stimulation. The expression of the mRNAs of TSHr and Tg did not significantly differ between hyperstimulated and KI-treated dogs while TPO and NIS mRNA expression decreased after a 48 h KI treatment. TPO and NIS are therefore the only of these four genes whose expression is acutely modulated by iodide in vivo. Under TSH stimulation low doses of iodide resulted in: (1) decreased cell proliferation, (2) reestablished synthesis and secretion of thyroid hormones, (3) diminished TPO and NIS mRNA expression. Notably low doses of iodide under the same conditions had no effect on Tg and TSHr mRNA expression.
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Affiliation(s)
- N Uyttersprot
- Institut de Recherche Interdisciplinaire, IRIBHN, Université Libre de Bruxelles, Campus Erasme, Belgium
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Gărtner R, Schopohl D, Schaefer S, Dugrillon A, Erdmann A, Toda S, Bechtner G. Regulation of transforming growth factor beta 1 messenger ribonucleic acid expression in porcine thyroid follicles in vitro by growth factors, iodine, or delta-iodolactone. Thyroid 1997; 7:633-40. [PMID: 9292955 DOI: 10.1089/thy.1997.7.633] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Transforming growth factor beta 1 (TGF beta 1) is an autocrine growth factor for thyrocytes and is supposed to be the mediator of iodine-induced growth inhibition of thyroid epithelial cells, but this is still controversial. We further investigated this hypothesis using intact porcine thyroid follicles ex vivo in a three-dimensional culture system. In this culture system it has been shown previously that both iodide as well as delta-iodolactone, the putative iodocompound mediating thyroid cell proliferation, inhibit growth of these follicles. We measured the amount of TGF beta 1 mRNA expression in these follicles after treatment either with thyrotropin (TSH), epidermal growth factor (EGF), or transforming growth factor alpha (TGF alpha) for growth stimulation or with inorganic iodine or delta-iodolactone in concentrations known to inhibit growth. TGF beta 1-mRNA was detected by Northern blot analysis. The known major transcript of 2.5 kb was detected in a steady state level up to 48 hours in untreated thyroid follicles. EGF and TGF alpha (5 ng/mL each) enhanced TGF beta 1 mRNA about threefold within 4 and 8 hours. This increase of TGF beta 1 mRNA was slightly decreased by simultaneous incubation with delta-iodolactone (1 microM) or iodide (40 microM KI). In contrast, both TSH (1 mU/mL) and forskolin (16 microM) decreased TGF beta 1 mRNA expression to about 70%, and this effect was abolished when follicles were pretreated with iodide (40 microM KI) in a concentration known to inhibit TSH action on cyclic adenosine monophosphate (cAMP) formation and proliferation. Iodide or delta-iodolactone alone had no significant effect on basal TGF beta 1 mRNA expression. We conclude that the growth inhibitory effect of iodide as well as of delta-iodolactone is not mediated through TGF beta 1 in intact porcine thyroid follicles ex vivo. The stimulatory effect of EGF and TGF alpha on TGF beta 1 expression might be related to extracellular matrix modulation during proliferation.
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Affiliation(s)
- R Gărtner
- Medizinische Klinik, Klinikum Innenstadt, Ludwig-Maximilians-Universitt München, Germany
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11 The cAMP in thyroid. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s1040-7952(97)80014-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Panneels V, Macours P, Van den Bergen H, Braekman JC, Van Sande J, Boeynaems JM. Biosynthesis and metabolism of 2-iodohexadecanal in cultured dog thyroid cells. J Biol Chem 1996; 271:23006-14. [PMID: 8798488 DOI: 10.1074/jbc.271.38.23006] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
2-Iodohexadecanal (2-IHDA) is a major thyroid iodolipid. It mimics the main regulatory effects of iodide on thyroid metabolism: inhibition of H2O2 production and of adenylyl cyclase. The biosynthesis of 2-IHDA and its metabolism have been investigated in cultured dog thyroid cells maintained in a differentiated state by forskolin. Incubation of these cells with [9,10-3H]hexadecan-1-ol or [9,10-3H]palmitic acid labeled several phospholipids, but [9, 10-3H]hexadecan-1-ol was selectively incorporated into plasmenylethanolamine. In the presence of an exogenous H2O2 generating system (glucose oxidase), iodide induced the production of [9,10-3H]2-IHDA from [9,10-3H]hexadecan-1-ol-labeled cells but not from [9,10-3H]palmitic acid-labeled cells. 2-IHDA was also generated during the lactoperoxidase-catalyzed iodination of brain and heart plasmalogens, and of ethyl hexadec-1-enyl ether, a synthetic vinyl ether-containing compound. Taken together, these results show that thyroid 2-IHDA is derived from plasmenylethanolamine via an attack of reactive iodine on the vinyl ether group. 2-Iodohexadecan-1-ol (2-IHDO) was also detected in these studies; it was formed later than 2-IHDA, and thyroid cells converted exogenous 2-IHDA into 2-IHDO in a time-dependent way. The ratio of 2-IHDO/2-IHDA increased with H2O2 production and decreased as a function of iodide concentration. An aldehyde-reducing activity was detected in subcellular fractions of the horse thyroid. No formation of 2-iodohexadecanoic acid could be detected. Reduction into the biologically inactive 2-IHDO is thus a major metabolic pathway of 2-IHDA in dog thyrocytes.
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Affiliation(s)
- V Panneels
- Institute of Interdisciplinary Research, School of Medicine, Free University of Brussels, Belgium
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Denef JF, Many MC, van den Hove MF. Iodine-induced thyroid inhibition and cell necrosis: two consequences of the same free-radical mediated mechanism? Mol Cell Endocrinol 1996; 121:101-3. [PMID: 8865171 DOI: 10.1016/0303-7207(96)03848-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- J F Denef
- Laboratory of Histology, University of Louvain, Medical School, Brussels, Belgium
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Jacoby C, Braekman JC, Daloze D. Asymmetric synthesis of (2R)- and (2S)-2-iodohexadecanal, natural inhibitors of the thyroid gland metabolism. Tetrahedron 1996. [DOI: 10.1016/0040-4020(96)00582-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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