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Alfandari A, Moskovich D, Weisz A, Katzav A, Kidron D, Beiner M, Josephy D, Asali A, Hants Y, Yagur Y, Weitzner O, Ellis M, Itchaki G, Ashur-Fabian O. The selenoenzyme type I iodothyronine deiodinase: a new tumor suppressor in ovarian cancer. Mol Oncol 2024. [PMID: 38429887 DOI: 10.1002/1878-0261.13612] [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: 08/27/2023] [Revised: 12/26/2023] [Accepted: 02/05/2024] [Indexed: 03/03/2024] Open
Abstract
The selenoenzyme type I iodothyronine deiodinase (DIO1) catalyzes removal of iodine atoms from thyroid hormones. Although DIO1 action is reported to be disturbed in several malignancies, no work has been conducted in high-grade serous ovarian carcinoma (HGSOC), the most lethal gynecologic cancer. We studied DIO1 expression in HGSOC patients [The Cancer Genome Atlas (TCGA) data and tumor tissues], human cell lines (ES-2 and Kuramochi), normal Chinese hamster ovarian cells (CHO-K1), and normal human fallopian tube cells (FT282 and FT109). To study its functional role, DIO1 was overexpressed, inhibited [by propylthiouracil (PTU)], or knocked down (KD), and cell count, proliferation, apoptosis, cell viability, and proteomics analysis were performed. Lower DIO1 levels were observed in HGSOC compared to normal cells and tissues. TCGA analyses confirmed that low DIO1 mRNA expression correlated with worse survival and therapy resistance in patients. Silencing or inhibiting the enzyme led to enhanced ovarian cancer proliferation, while an opposite effect was shown following DIO1 ectopic expression. Proteomics analysis in DIO1-KD cells revealed global changes in proteins that facilitate tumor metabolism and progression. In conclusion, DIO1 expression and ovarian cancer progression are inversely correlated, highlighting a tumor suppressive role for this enzyme and its potential use as a biomarker in this disease.
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Affiliation(s)
- Adi Alfandari
- Translational Oncology Laboratory, Hematology Institute, Meir Medical Center, Kfar Saba, Israel
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine, Tel Aviv University, Israel
- School of Medicine, Faculty of Medical and Health Sciences, Tel Aviv University, Israel
| | - Dotan Moskovich
- Translational Oncology Laboratory, Hematology Institute, Meir Medical Center, Kfar Saba, Israel
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine, Tel Aviv University, Israel
- School of Medicine, Faculty of Medical and Health Sciences, Tel Aviv University, Israel
| | - Avivit Weisz
- Department of Pathology, Meir Medical Center, Kfar Saba, Israel
| | - Aviva Katzav
- Department of Pathology, Meir Medical Center, Kfar Saba, Israel
| | - Debora Kidron
- School of Medicine, Faculty of Medical and Health Sciences, Tel Aviv University, Israel
- Department of Pathology, Meir Medical Center, Kfar Saba, Israel
| | - Mario Beiner
- School of Medicine, Faculty of Medical and Health Sciences, Tel Aviv University, Israel
- Division of Gynecologic Oncology, Meir Medical Center, Kfar Saba, Israel
| | - Dana Josephy
- Division of Gynecologic Oncology, Meir Medical Center, Kfar Saba, Israel
| | - Aula Asali
- Division of Gynecologic Oncology, Meir Medical Center, Kfar Saba, Israel
| | - Yael Hants
- Division of Gynecologic Oncology, Meir Medical Center, Kfar Saba, Israel
| | - Yael Yagur
- Department of Obstetrics and Gynecology, Meir Medical Center, Kfar Saba, Israel
| | - Omer Weitzner
- Department of Obstetrics and Gynecology, Meir Medical Center, Kfar Saba, Israel
| | - Martin Ellis
- Translational Oncology Laboratory, Hematology Institute, Meir Medical Center, Kfar Saba, Israel
- School of Medicine, Faculty of Medical and Health Sciences, Tel Aviv University, Israel
| | - Gilad Itchaki
- Translational Oncology Laboratory, Hematology Institute, Meir Medical Center, Kfar Saba, Israel
- School of Medicine, Faculty of Medical and Health Sciences, Tel Aviv University, Israel
| | - Osnat Ashur-Fabian
- Translational Oncology Laboratory, Hematology Institute, Meir Medical Center, Kfar Saba, Israel
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine, Tel Aviv University, Israel
- School of Medicine, Faculty of Medical and Health Sciences, Tel Aviv University, Israel
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Goto K, Kimura R, Masuda R, Karasaki T, Sase S. Demonstration of the Formation of a Selenocysteine Selenenic Acid through Hydrolysis of a Selenocysteine Selenenyl Iodide Utilizing a Protective Molecular Cradle. Molecules 2023; 28:7972. [PMID: 38138461 PMCID: PMC10746021 DOI: 10.3390/molecules28247972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 12/01/2023] [Accepted: 12/04/2023] [Indexed: 12/24/2023] Open
Abstract
Selenocysteine selenenic acids (Sec-SeOHs) and selenocysteine selenenyl iodides (Sec-SeIs) have long been recognized as crucial intermediates in the catalytic cycle of glutathione peroxidase (GPx) and iodothyronine deiodinase (Dio), respectively. However, the observation of these reactive species remained elusive until our recent study, where we successfully stabilized Sec-SeOHs and Sec-SeIs using a protective molecular cradle. Here, we report the first demonstration of the chemical transformation from a Sec-SeI to a Sec-SeOH through alkaline hydrolysis. A stable Sec-SeI derived from a selenocysteine methyl ester was synthesized using the protective cradle, and its structure was determined by crystallographic analysis. The alkaline hydrolysis of the Sec-SeI at -50 °C yielded the corresponding Sec-SeOH in an 89% NMR yield, the formation of which was further confirmed by its reaction with dimedone. The facile and nearly quantitative conversion of the Sec-SeI to the Sec-SeOH not only validates the potential involvement of this process in the catalytic mechanism of Dio, but also highlights its utility as a method for producing a Sec-SeOH.
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Affiliation(s)
- Kei Goto
- Department of Chemistry, School of Science, Tokyo Institute of Technology, Tokyo 152-8551, Japan
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Iodine Status in Pregnant Women Having Urinary Fluoride in Contaminated Areas: A Case Study of Phayao Province. JOURNAL OF ENVIRONMENTAL AND PUBLIC HEALTH 2023; 2023:3677359. [PMID: 36755777 PMCID: PMC9902143 DOI: 10.1155/2023/3677359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 07/22/2022] [Accepted: 01/02/2023] [Indexed: 01/31/2023]
Abstract
Fluoride naturally occurs in the Earth's crust and is widely dispersed in groundwater. The high consumption of fluoride can inhibit iodine metabolism in the human body, especially in the thyroid gland. This study assessed iodine knowledge, iodine consumption behavior, urinary iodine (UI), thyroid stimulating hormone (serum TSH), and free triiodothyronine3 (serum FT3) and examined the connection between fluoride exposure and UI and thyroid function as serum concentrations of TSH and FT3 in pregnant women dwelling in an area of endemic fluorosis. This was a cross-sectional study. The population included 152 pregnant women within the 1st trimester of pregnancy, during which they were provided antenatal care (ANC) in seven public community hospitals in Phayao province, Thailand. The study consisted of two components. First, the study consisted of a questionnaire in which we evaluated the iodine knowledge and iodine consumptive behaviors in subjects. Second, biochemical data were investigated to evaluate thyroid function in the subjects. The gestational age of most subjects was 8-12 weeks. The study population has lived in fluoride-contaminated areas since birth (76.97%). The iodine and iodine consumption levels were moderate (50.00%). Their food iodine consumption was 3-4 days/week, and the top five consumption ranks were iodized salt, cooked pork, eggs, sticky rice, and iodine fish sauce. In terms of biochemical parameters, 63.16% of respondents had UI levels below 150.00 g/L, which is below the normal reference range of 150.00-249.00 g/L. 89.47% of the risk of hypothyroidism was associated with serum TSH levels below 2.50 g/L. In 38.16% of the samples, normal levels of serum FT3 (2.00-4.40 pg/L) were identified in the subjects. In addition, 61.84% of the samples had FT3 concentrations greater than 4.40 pg/L (high intake of iodine). The approved association between positive serum FT3 data and serum TSH was positive (r = 260 and p < 0.05). These studies imply that these elevated levels of TSH and FT3 place pregnant women in their first trimester at risk for hypothyroidism.
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Dracheva E, Norinder U, Rydén P, Engelhardt J, Weiss JM, Andersson PL. In Silico Identification of Potential Thyroid Hormone System Disruptors among Chemicals in Human Serum and Chemicals with a High Exposure Index. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:8363-8372. [PMID: 35561338 PMCID: PMC9228062 DOI: 10.1021/acs.est.1c07762] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 04/27/2022] [Accepted: 04/29/2022] [Indexed: 05/30/2023]
Abstract
Data on toxic effects are at large missing the prevailing understanding of the risks of industrial chemicals. Thyroid hormone (TH) system disruption includes interferences of the life cycle of the thyroid hormones and may occur in various organs. In the current study, high-throughput screening data available for 14 putative molecular initiating events of adverse outcome pathways, related to disruption of the TH system, were used to develop 19 in silico models for identification of potential thyroid hormone system-disrupting chemicals. The conformal prediction framework with the underlying Random Forest was used as a wrapper for the models allowing for setting the desired confidence level and controlling the error rate of predictions. The trained models were then applied to two different databases: (i) an in-house database comprising xenobiotics identified in human blood and ii) currently used chemicals registered in the Swedish Product Register, which have been predicted to have a high exposure index to consumers. The application of these models showed that among currently used chemicals, fewer were overall predicted as active compared to chemicals identified in human blood. Chemicals of specific concern for TH disruption were identified from both databases based on their predicted activity.
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Affiliation(s)
- Elena Dracheva
- Department
of Chemistry, Umeå University, KB.E6, Linnaeus väg 6, SE-901 87 Umeå, Sweden
| | - Ulf Norinder
- Department
of Computer and Systems Sciences, Stockholm
University, Box 7003, SE-164 07 Kista, Sweden
| | - Patrik Rydén
- Department
of Mathematics and Mathematical Statistics, Umeå University, MIT.E.351, SE-901 87 Umeå, Sweden
| | - Josefin Engelhardt
- Department
of Environmental Science, Stockholm University, SE-11418 Stockholm, Sweden
| | - Jana M. Weiss
- Department
of Environmental Science, Stockholm University, SE-11418 Stockholm, Sweden
| | - Patrik L. Andersson
- Department
of Chemistry, Umeå University, KB.E6, Linnaeus väg 6, SE-901 87 Umeå, Sweden
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Rodriguez-Ruiz A, Braun D, Pflug S, Brol A, Sylvester M, Steegborn C, Schweizer U. Insights into the Mechanism of Human Deiodinase 1. Int J Mol Sci 2022; 23:5361. [PMID: 35628173 PMCID: PMC9141512 DOI: 10.3390/ijms23105361] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 05/03/2022] [Accepted: 05/09/2022] [Indexed: 02/07/2023] Open
Abstract
The three isoenzymes of iodothyronine deiodinases (DIO1-3) are membrane-anchored homo-dimeric selenoproteins which share the thioredoxin-fold structure. Several questions regarding their catalytic mechanisms still remain open. Here, we addressed the roles of several cysteines which are conserved among deiodinase isoenzymes and asked whether they may contribute to dimerization and reduction of the oxidized enzyme with physiological reductants. We also asked whether amino acids previously identified in DIO3 play the same role in DIO1. Human DIO1 and 2 were recombinantly expressed in insect cells with selenocysteine replaced with cysteine (DIO1U126C) or in COS7 cells as selenoprotein. Enzyme activities were studied by radioactive deiodination assays with physiological reducing agents and recombinant proteins were characterized by mass spectrometry. Mutation of Cys124 in DIO1 prevented reduction by glutathione, while 20 mM dithiothreitol still regenerated the enzyme. Protein thiol reductants, thioredoxin and glutaredoxin, did not reduce DIO1U126C. Mass spectrometry demonstrated the formation of an intracellular disulfide between the side-chains of Cys124 and Cys(Sec)126. We conclude that the proximal Cys124 forms a selenenyl-sulfide with the catalytic Sec126 during catalysis, which is the substrate of the physiological reductant glutathione. Mutagenesis studies support the idea of a proton-relay pathway from solvent to substrate that is shared between DIO1 and DIO3.
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Affiliation(s)
- Alfonso Rodriguez-Ruiz
- Institut für Biochemie und Molekularbiologie, Universitätsklinikum Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany; (A.R.-R.); (D.B.); (S.P.); (A.B.)
| | - Doreen Braun
- Institut für Biochemie und Molekularbiologie, Universitätsklinikum Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany; (A.R.-R.); (D.B.); (S.P.); (A.B.)
| | - Simon Pflug
- Institut für Biochemie und Molekularbiologie, Universitätsklinikum Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany; (A.R.-R.); (D.B.); (S.P.); (A.B.)
| | - Alexander Brol
- Institut für Biochemie und Molekularbiologie, Universitätsklinikum Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany; (A.R.-R.); (D.B.); (S.P.); (A.B.)
| | - Marc Sylvester
- Core Facility Mass Spectrometry, Universitätsklinikum Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany;
| | | | - Ulrich Schweizer
- Institut für Biochemie und Molekularbiologie, Universitätsklinikum Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany; (A.R.-R.); (D.B.); (S.P.); (A.B.)
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Kahaly GJ, Gottwald-Hostalek U. Use of levothyroxine in the management of hypothyroidism: A historical perspective. Front Endocrinol (Lausanne) 2022; 13:1054983. [PMID: 36407302 PMCID: PMC9666762 DOI: 10.3389/fendo.2022.1054983] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 10/10/2022] [Indexed: 11/07/2022] Open
Abstract
The thyroid operates within a complex system of homeostatic regulation, where the level of thyrotropin (TSH) influences the rate of secretion of the principal thyroid hormones, thyroxine (T4) and triiodothyronine (T3). The devastating consequences of untreated thyroid dysfunction have been evident for centuries. Indeed, sources from antiquity described goitre and cretinism, two of the clinical sequelae of untreated overt thyroid disease. It was not until the first part of the 19th century that goitre and cretinism were first associated with iodine status; however, the endocrine function of the thyroid was not clearly identified until the early part of the 20th century. Three principal innovations in the 20th century supported the use of levothyroxine (LT4) replacement therapy for the management of hypothyroidism: a practical technique for the synthesis of LT4 suitable to support pharmaceutical use (late 1940s), the discovery that LT4 is converted to the active thyroid hormone, T3, in the peripheral tissues (1970), and the development of robust and sensitive assay methodology for measuring thyroid hormones in the blood (1960 onwards). Synthetic LT4, titrated to bring the level of TSH within a predefined "normal" reference range, is now established as the mainstay of treatment for hypothyroidism, and provides adequate restoration of thyroid hormone function for most people with this condition. Future research will explore further the nuances of the hypothalamic-pituitary-thyroid axis, and the place, if any, for T3 within the management of thyroid dysfunction.
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Affiliation(s)
- George J. Kahaly
- Department of Medicine I, Johannes Gutenberg University (JGU) Medical Center, Mainz, Germany
- *Correspondence: George J. Kahaly,
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Targeting the DIO3 enzyme using first-in-class inhibitors effectively suppresses tumor growth: a new paradigm in ovarian cancer treatment. Oncogene 2021; 40:6248-6257. [PMID: 34556811 DOI: 10.1038/s41388-021-02020-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 08/26/2021] [Accepted: 09/10/2021] [Indexed: 02/08/2023]
Abstract
The enzyme iodothyronine deiodinase type 3 (DIO3) contributes to cancer proliferation by inactivating the tumor-suppressive actions of thyroid hormone (T3). We recently established DIO3 involvement in the progression of high-grade serous ovarian cancer (HGSOC). Here we provide a link between high DIO3 expression and lower survival in patients, similar to common disease markers such as Ki67, PAX8, CA-125, and CCNE1. These observations suggest that DIO3 is a logical target for inhibition. Using a DIO3 mimic, we developed original DIO3 inhibitors that contain a core of dibromomaleic anhydride (DBRMD) as scaffold. Two compounds, PBENZ-DBRMD and ITYR-DBRMD, demonstrated attenuated cell counts, induction in apoptosis, and a reduction in cell proliferation in DIO3-positive HGSOC cells (OVCAR3 and KURAMOCHI), but not in DIO3-negative normal ovary cells (CHOK1) and OVCAR3 depleted for DIO3 or its substrate, T3. Potent tumor inhibition with a high safety profile was further established in HGSOC xenograft model, with no effect in DIO3-depleted tumors. The antitumor effects are mediated by downregulation in an array of pro-cancerous proteins, the majority of which known to be repressed by T3. To conclude, using small molecules that specifically target the DIO3 enzyme we present a new treatment paradigm for ovarian cancer and potentially other DIO3-dependent malignancies.
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Rousseau K, Dufour S, Sachs LM. Interdependence of Thyroid and Corticosteroid Signaling in Vertebrate Developmental Transitions. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.735487] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Post-embryonic acute developmental processes mainly allow the transition from one life stage in a specific ecological niche to the next life stage in a different ecological niche. Metamorphosis, an emblematic type of these post-embryonic developmental processes, has occurred repeatedly and independently in various phylogenetic groups throughout metazoan evolution, such as in cnidarian, insects, molluscs, tunicates, or vertebrates. This review will focus on metamorphoses and developmental transitions in vertebrates, including typical larval metamorphosis in anuran amphibians, larval and secondary metamorphoses in teleost fishes, egg hatching in sauropsids and birth in mammals. Two neuroendocrine axes, the hypothalamic-pituitary-thyroid and the hypothalamic-pituitary-adrenal/interrenal axes, are central players in the regulation of these life transitions. The review will address the molecular and functional evolution of these axes and their interactions. Mechanisms of integration of internal and environmental cues, and activation of these neuroendocrine axes represent key questions in an “eco-evo-devo” perspective of metamorphosis. The roles played by developmental transitions in the innovation, adaptation, and plasticity of life cycles throughout vertebrates will be discussed. In the current context of global climate change and habitat destruction, the review will also address the impact of environmental factors, such as global warming and endocrine disruptors on hypothalamic-pituitary-thyroid and hypothalamic-pituitary-adrenal/interrenal axes, and regulation of developmental transitions.
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Schiera G, Di Liegro CM, Di Liegro I. Involvement of Thyroid Hormones in Brain Development and Cancer. Cancers (Basel) 2021; 13:2693. [PMID: 34070729 PMCID: PMC8197921 DOI: 10.3390/cancers13112693] [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: 05/12/2021] [Revised: 05/26/2021] [Accepted: 05/27/2021] [Indexed: 12/21/2022] Open
Abstract
The development and maturation of the mammalian brain are regulated by thyroid hormones (THs). Both hypothyroidism and hyperthyroidism cause serious anomalies in the organization and function of the nervous system. Most importantly, brain development is sensitive to TH supply well before the onset of the fetal thyroid function, and thus depends on the trans-placental transfer of maternal THs during pregnancy. Although the mechanism of action of THs mainly involves direct regulation of gene expression (genomic effects), mediated by nuclear receptors (THRs), it is now clear that THs can elicit cell responses also by binding to plasma membrane sites (non-genomic effects). Genomic and non-genomic effects of THs cooperate in modeling chromatin organization and function, thus controlling proliferation, maturation, and metabolism of the nervous system. However, the complex interplay of THs with their targets has also been suggested to impact cancer proliferation as well as metastatic processes. Herein, after discussing the general mechanisms of action of THs and their physiological effects on the nervous system, we will summarize a collection of data showing that thyroid hormone levels might influence cancer proliferation and invasion.
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Affiliation(s)
- Gabriella Schiera
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche) (STEBICEF), University of Palermo, 90128 Palermo, Italy; (G.S.); (C.M.D.L.)
| | - Carlo Maria Di Liegro
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche) (STEBICEF), University of Palermo, 90128 Palermo, Italy; (G.S.); (C.M.D.L.)
| | - Italia Di Liegro
- Department of Biomedicine, Neurosciences and Advanced Diagnostics (Dipartimento di Biomedicina, Neuroscienze e Diagnostica avanzata) (Bi.N.D.), University of Palermo, 90127 Palermo, Italy
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10
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Abstract
Iodothyronine deiodinases (Dios) are important selenoproteins that control the concentration of the active thyroid hormone (TH) triiodothyronine through regioselective deiodination. The X-ray structure of a truncated monomer of Type III Dio (Dio3), which deiodinates TH inner rings through a selenocysteine (Sec) residue, revealed a thioredoxin-fold catalytic domain supplemented with an unstructured Ω-loop. Loop dynamics are driven by interactions of the conserved Trp207 with solvent in multi-microsecond molecular dynamics simulations of the Dio3 thioredoxin(Trx)-fold domain. Hydrogen bonding interactions of Glu200 with residues conserved across the Dio family anchor the loop’s N-terminus to the active site Ser-Cys-Thr-Sec sequence. A key long-lived loop conformation coincides with the opening of a cryptic pocket that accommodates thyroxine (T4) through an I⋯Se halogen bond to Sec170 and the amino acid group with a polar cleft. The Dio3-T4 complex is stabilized by an I⋯O halogen bond between an outer ring iodine and Asp211, consistent with Dio3 selectivity for inner ring deiodination. Non-conservation of residues, such as Asp211, in other Dio types in the flexible portion of the loop sequence suggests a mechanism for regioselectivity through Dio type-specific loop conformations. Cys168 is proposed to attack the selenenyl iodide intermediate to regenerate Dio3 based upon structural comparison with related Trx-fold proteins.
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Giammanco M, Di Liegro CM, Schiera G, Di Liegro I. Genomic and Non-Genomic Mechanisms of Action of Thyroid Hormones and Their Catabolite 3,5-Diiodo-L-Thyronine in Mammals. Int J Mol Sci 2020; 21:ijms21114140. [PMID: 32532017 PMCID: PMC7312989 DOI: 10.3390/ijms21114140] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 06/05/2020] [Accepted: 06/08/2020] [Indexed: 02/06/2023] Open
Abstract
Since the realization that the cellular homologs of a gene found in the retrovirus that contributes to erythroblastosis in birds (v-erbA), i.e. the proto-oncogene c-erbA encodes the nuclear receptors for thyroid hormones (THs), most of the interest for THs focalized on their ability to control gene transcription. It was found, indeed, that, by regulating gene expression in many tissues, these hormones could mediate critical events both in development and in adult organisms. Among their effects, much attention was given to their ability to increase energy expenditure, and they were early proposed as anti-obesity drugs. However, their clinical use has been strongly challenged by the concomitant onset of toxic effects, especially on the heart. Notably, it has been clearly demonstrated that, besides their direct action on transcription (genomic effects), THs also have non-genomic effects, mediated by cell membrane and/or mitochondrial binding sites, and sometimes triggered by their endogenous catabolites. Among these latter molecules, 3,5-diiodo-L-thyronine (3,5-T2) has been attracting increasing interest because some of its metabolic effects are similar to those induced by T3, but it seems to be safer. The main target of 3,5-T2 appears to be the mitochondria, and it has been hypothesized that, by acting mainly on mitochondrial function and oxidative stress, 3,5-T2 might prevent and revert tissue damages and hepatic steatosis induced by a hyper-lipid diet, while concomitantly reducing the circulating levels of low density lipoproteins (LDL) and triglycerides. Besides a summary concerning general metabolism of THs, as well as their genomic and non-genomic effects, herein we will discuss resistance to THs and the possible mechanisms of action of 3,5-T2, also in relation to its possible clinical use as a drug.
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Affiliation(s)
- Marco Giammanco
- Department of Surgical, Oncological and Oral Sciences (Discipline Chirurgiche, Oncologiche e Stomatologiche), University of Palermo, 90127 Palermo, Italy;
| | - Carlo Maria Di Liegro
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF)), University of Palermo, 90128 Palermo, Italy; (C.M.D.L.); (G.S.)
| | - Gabriella Schiera
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF)), University of Palermo, 90128 Palermo, Italy; (C.M.D.L.); (G.S.)
| | - Italia Di Liegro
- Department of Biomedicine, Neurosciences and Advanced Diagnostics (Dipartimento di Biomedicina, Neuroscienze e Diagnostica avanzata (Bi.N.D.)), University of Palermo, 90127 Palermo, Italy
- Correspondence: ; Tel.: +39-091-2389-7415 or +39-091-2389-7446
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