1
|
Lossow K, Renko K, Schwarz M, Schomburg L, Schwerdtle T, Kipp AP. The Nutritional Supply of Iodine and Selenium Affects Thyroid Hormone Axis Related Endpoints in Mice. Nutrients 2021; 13:nu13113773. [PMID: 34836027 PMCID: PMC8625755 DOI: 10.3390/nu13113773] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/21/2021] [Accepted: 10/22/2021] [Indexed: 01/06/2023] Open
Abstract
Selenium and iodine are the two central trace elements for the homeostasis of thyroid hormones but additional trace elements such as iron, zinc, and copper are also involved. To compare the primary effects of inadequate intake of selenium and iodine on the thyroid gland, as well as the target organs of thyroid hormones such as liver and kidney, mice were subjected to an eight-week dietary intervention with low versus adequate selenium and iodine supply. Analysis of trace element levels in serum, liver, and kidney demonstrated a successful intervention. Markers of the selenium status were unaffected by the iodine supply. The thyroid gland was able to maintain serum thyroxine levels even under selenium-deficient conditions, despite reduced selenoprotein expression in liver and kidney, including deiodinase type 1. Thyroid hormone target genes responded to the altered selenium and iodine supply, whereas the iron, zinc, and copper homeostasis remained unaffected. There was a notable interaction between thyroid hormones and copper, which requires further clarification. Overall, the effects of an altered selenium and iodine supply were pronounced in thyroid hormone target tissues, but not in the thyroid gland.
Collapse
Affiliation(s)
- Kristina Lossow
- Department of Nutritional Physiology, Institute of Nutritional Sciences, Friedrich Schiller University Jena, 07743 Jena, Germany; (K.L.); (M.S.)
- TraceAge-DFG Research Unit on Interactions of Essential Trace Elements in Healthy and Diseased Elderly, 07743 Jena, Germany; (L.S.); (T.S.)
- German Institute of Human Nutrition, 14558 Nuthetal, Germany
| | - Kostja Renko
- German Federal Institute for Risk Assessment (BfR), 12277 Berlin, Germany;
| | - Maria Schwarz
- Department of Nutritional Physiology, Institute of Nutritional Sciences, Friedrich Schiller University Jena, 07743 Jena, Germany; (K.L.); (M.S.)
- TraceAge-DFG Research Unit on Interactions of Essential Trace Elements in Healthy and Diseased Elderly, 07743 Jena, Germany; (L.S.); (T.S.)
| | - Lutz Schomburg
- TraceAge-DFG Research Unit on Interactions of Essential Trace Elements in Healthy and Diseased Elderly, 07743 Jena, Germany; (L.S.); (T.S.)
- Institute for Experimental Endocrinology, Charité-University Medical School Berlin, 13353 Berlin, Germany
| | - Tanja Schwerdtle
- TraceAge-DFG Research Unit on Interactions of Essential Trace Elements in Healthy and Diseased Elderly, 07743 Jena, Germany; (L.S.); (T.S.)
- German Federal Institute for Risk Assessment (BfR), 12277 Berlin, Germany;
- Department of Food Chemistry, Institute of Nutritional Science, University of Potsdam, 14558 Nuthetal, Germany
| | - Anna Patricia Kipp
- Department of Nutritional Physiology, Institute of Nutritional Sciences, Friedrich Schiller University Jena, 07743 Jena, Germany; (K.L.); (M.S.)
- TraceAge-DFG Research Unit on Interactions of Essential Trace Elements in Healthy and Diseased Elderly, 07743 Jena, Germany; (L.S.); (T.S.)
- Correspondence:
| |
Collapse
|
2
|
Damiano F, Rochira A, Gnoni A, Siculella L. Action of Thyroid Hormones, T3 and T2, on Hepatic Fatty Acids: Differences in Metabolic Effects and Molecular Mechanisms. Int J Mol Sci 2017; 18:ijms18040744. [PMID: 28362337 PMCID: PMC5412329 DOI: 10.3390/ijms18040744] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Revised: 03/22/2017] [Accepted: 03/27/2017] [Indexed: 12/28/2022] Open
Abstract
The thyroid hormones (THs) 3,3′,5,5′-tetraiodo-l-thyronine (T4) and 3,5,3′-triiodo-l-thyronine (T3) influence many metabolic pathways. The major physiological function of THs is to sustain basal energy expenditure, by acting primarily on carbohydrate and lipid catabolism. Beyond the mobilization and degradation of lipids, at the hepatic level THs stimulate the de novo fatty acid synthesis (de novo lipogenesis, DNL), through both the modulation of gene expression and the rapid activation of cell signalling pathways. 3,5-Diiodo-l-thyronine (T2), previously considered only a T3 catabolite, has been shown to mimic some of T3 effects on lipid catabolism. However, T2 action is more rapid than that of T3, and seems to be independent of protein synthesis. An inhibitory effect on DNL has been documented for T2. Here, we give an overview of the mechanisms of THs action on liver fatty acid metabolism, focusing on the different effects exerted by T2 and T3 on the regulation of the DNL. The inhibitory action on DNL exerted by T2 makes this compound a potential and attractive drug for the treatment of some metabolic diseases and cancer.
Collapse
Affiliation(s)
- Fabrizio Damiano
- Laboratory of Biochemistry and Molecular Biology, Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy.
| | - Alessio Rochira
- Laboratory of Biochemistry and Molecular Biology, Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy.
| | - Antonio Gnoni
- Department of Basic Medical Sciences, Section of Medical Biochemistry, University of Bari Aldo Moro, 70125 Bari, Italy.
| | - Luisa Siculella
- Laboratory of Biochemistry and Molecular Biology, Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy.
| |
Collapse
|
3
|
Stefos GC, Becker W, Lampidonis AD, Rogdakis E. Cloning and functional characterization of the ovine malic enzyme promoter. Gene 2008; 428:36-40. [PMID: 18952156 DOI: 10.1016/j.gene.2008.09.027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Revised: 09/25/2008] [Accepted: 09/30/2008] [Indexed: 10/21/2022]
Abstract
While in human and rodents lipogenesis occurs predominantly in the liver, adipose tissue is the major site in ruminants. Here we report the nucleotide sequence of the 5'-flanking region of the ovine malic enzyme gene (ME1). The ME1 promoter is located within a GC-rich region fulfilling the criteria of CpG islands and lacks a TATA-box. Deletion analysis identified a region (-231/-170) that suppressed promoter activity in luciferase assays in HepG2 hepatoma cells but not in 3T3-L1 adipocytes. This region contains a putative triiodothyronine response element (T3RE) that differs from the human ME1 T3RE by two nucleotides. When the human ME1 T3RE was introduced into the ovine ME1 promoter context, transcriptional activity was increased in the hepatic cell lines HepG2 and H4IIE but not in differentiated 3T3-L1 cells. Our results suggest that the sequence of the T3RE in the ME1 promoter determines differences in the tissue/species activity of malic enzyme in ruminants and human.
Collapse
Affiliation(s)
- Georgios C Stefos
- Department of Animal Science, Laboratory of Animal Breeding and Husbandry, Agricultural University of Athens, Iera Odos 75, Athens, Greece.
| | | | | | | |
Collapse
|
4
|
O'Shea PJ, Guigon CJ, Williams GR, Cheng SY. Regulation of fibroblast growth factor receptor-1 (FGFR1) by thyroid hormone: identification of a thyroid hormone response element in the murine Fgfr1 promoter. Endocrinology 2007; 148:5966-76. [PMID: 17761769 DOI: 10.1210/en.2007-0114] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
T(3) is essential for normal skeletal development, acting mainly via the TRalpha1 nuclear receptor. Nevertheless, the mechanisms of T(3) action in bone are poorly defined. Fibroblast growth factor receptor-1 (FGFR1) is also essential for bone formation. Fgfr1 expression and activity are positively regulated by T(3) in osteoblasts, and in mice that harbor a dominant negative PV mutation targeted to TRalpha1 or TRbeta, Fgfr1 expression is sensitive to skeletal thyroid status. To investigate mechanisms underlying T(3) regulation of FGFR1, we obtained primary calvarial osteoblasts from wild-type and TRbeta(PV/PV) littermate mice. T(3) treatment increased Fgfr1 expression 2-fold in wild-type cells, but 8-fold in TRbeta(PV/PV) osteoblasts. The 4-fold increased T(3) sensitivity of TRbeta(PV/PV) osteoblasts was associated with a markedly increased ratio of TRalpha1:TRbeta1 expression that resulted from reduced TRbeta1 expression in TRbeta(PV/PV) osteoblasts compared with wild-type. Bioinformatics and gel shift studies, and mutational analysis, identified a specific TR binding site 279-264 nucleotides upstream of the murine Fgfr1 promoter transcription start site. Transient transfection analysis of a series of Fgfr1 promoter 5'-deletion constructs, of a mutant reporter construct, and a series of heterologous promoter constructs, confirmed that this region of the promoter mediates a TR-dependent transcriptional response to T(3). Thus, in addition to indirect regulation of FGFR1 expression by T(3) reported previously, T(3) also activates the Fgfr1 promoter directly via a thyroid hormone response element located at positions -279/-264.
Collapse
Affiliation(s)
- Patrick J O'Shea
- Gene Regulation Section, Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-4264, USA
| | | | | | | |
Collapse
|
5
|
Chou WY, Cheng YS, Ho CL, Liu ST, Liu PY, Kuo CC, Chang HP, Chen YH, Chang GG, Huang SM. Human spot 14 protein interacts physically and functionally with the thyroid receptor. Biochem Biophys Res Commun 2007; 357:133-8. [PMID: 17418816 DOI: 10.1016/j.bbrc.2007.03.103] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2007] [Accepted: 03/19/2007] [Indexed: 12/31/2022]
Abstract
Spot 14 (S14) is a small acidic protein with no sequence similarity to other mammalian gene products. Its biochemical function is elusive. Recent studies have shown that, in some cancers, human S14 (hS14) localizes to the nucleus and is amplified, suggesting that it plays a role in the regulation of lipogenic enzymes during tumorigenesis. In this study, we purified untagged hS14 protein and then demonstrated, using various biochemical methods, including analytic ultracentrifugation, that hS14 might form a homodimer. We also found several lines of evidence to suggest physical and functional interactions between hS14 and the thyroid hormone receptor (TR). The ubiquitous expression of hS14 in various cell lines and its cell-type-dependent functions demonstrated in this study suggest that it acts as a positive or negative cofactor of the TR to regulate malic enzyme gene expression. These findings provide a molecular rationale for the role of hS14 in TR-dependent transcriptional activation of the expression of specific genes.
Collapse
Affiliation(s)
- Wei-Yuan Chou
- Department of Biochemistry, National Defense Medical Center, Taipei 114, Taiwan, ROC
| | | | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Yang ML, Huang TS, Lee Y, Chen TH, Chen SY, Lu FJ. Inhibition of endogenous thyroid hormone receptor-beta and peroxisome proliferator-activated receptor-alpha activities by humic acid in a human-derived liver cell line. Thyroid 2002; 12:361-71. [PMID: 12097195 DOI: 10.1089/105072502760043422] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Humic acid (HA), know to be ubiquitous in the natural environment, is present in almost all soil, surface water, and plants. Earlier studies indicate that HA can affect thyroid economy via binding with iodide, inhibiting both thyroid peroxidase and hepatic 5'-deiodinase in rodents. However, the effect of HA, a peroxisome proliferator in rodents, on thyroid hormone receptor (TR) and peroxisome proliferator-activated receptor (PPAR) in human cells has not yet been examined. In this study, we demonstrate that the malic enzyme activity and the transcriptional activities of endogenous TR and PPAR were inhibited after treatment with HA in human hepatocyte Chang liver cell line. Although the protein expression levels of TR-beta, PPAR-alpha and retinoid X receptor-alpha (RXRalpha) were not changed significantly by HA treatment, both the binding abilities of endogenous TR-beta on thyroid hormone response element (TRE) and PPAR-alpha on the PPAR response element (PPRE) were inhibited by HA treatment. The study of the subcellular distribution of HA, relying on the inherent HA fluorescence, showed that HA distributed in the intracellular compartments including cytoplasm and nucleus. The 50% binding inhibition values (CI(50)) of HA on ME-TRE (malic enzyme gene-TRE) and ACOX-PPRE (acylCoA oxidase gene-PPRE) were 19.31 and 19.94 microg/mL, respectively. These results suggest that HA-induced endemic goiter may link in part to the disruption of TRbeta and PPARalpha function in human Chang liver cells. This model may be useful in the investigation of environmental goitrogens.
Collapse
Affiliation(s)
- Mei-Ling Yang
- Graduate Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei, Taiwan, Republic of China
| | | | | | | | | | | |
Collapse
|
7
|
Butta N, González-Manchón C, Arias-Salgado EG, Ayuso MS, Parrilla R. Cloning and functional characterization of the 5′ flanking region of the human mitochondrial malic enzyme gene. ACTA ACUST UNITED AC 2001; 268:3017-27. [PMID: 11358520 DOI: 10.1046/j.1432-1327.2001.02194.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This work reports the molecular cloning and functional characterization of the 5' flanking region of the human mitochondrial malic enzyme (mME) gene. The proximal promoter region has features of housekeeping genes like high G + C-content and absence of TATA or CCAAT boxes. Deletion analysis of the 5' region of the mME showed that maximal transcriptional activity is located within the -205/+86 region. Footprinting analysis showed two protected regions, one comprising potential overlapped AP-1, CREB, and AP-4 sites and a second one encompassing AP-2 and several Sp1 ci-acting elements. Mutation of putative AP-1/AP-4/CREB sites reduced basal promoter activity to less than 50%. Supershift assays demonstrated the specific binding of Sp1 and AP-2 proteins. Moreover, experiments in Drosophila SL2 cells lacking endogenous Sp1 demonstrated that the Sp1 site(s) is essential to maintain a normal basal rate of transcription of this gene. A low-level expression of AP-2 enhanced the activity of a mME promoter construct in HepG2 cells and this effect was prevented by disruption of the putative AP-2 element. In contrast, higher levels of expression of AP-2 induced a DNA-independent inhibitory response. A biphasic regulation of endogenous mME gene is also shown in HepG2 cells transfected with an AP-2 expression plasmid, suggesting that availability of AP-2 protein may control this gene under physiological conditions. A recombinant lambda genomic clone containing a mME pseudogene was also isolated. The high degree of sequence conservation seems to indicate a recent emergency of this human pseudogene.
Collapse
Affiliation(s)
- N Butta
- Department of Pathophysiology and Human Molecular Genetics, Centro de Investigaciones Biológicas (CSIC), Madrid, Spain
| | | | | | | | | |
Collapse
|
8
|
Wang Y, Yin L, Hillgartner FB. The homeodomain proteins PBX and MEIS1 are accessory factors that enhance thyroid hormone regulation of the malic enzyme gene in hepatocytes. J Biol Chem 2001; 276:23838-48. [PMID: 11331288 DOI: 10.1074/jbc.m102166200] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Triiodothyronine (T3) stimulates a robust increase (>40-fold) in transcription of the malic enzyme gene in chick embryo hepatocytes. Previous work has shown that optimal T3 regulation of malic enzyme transcription is dependent on the presence of an accessory element (designated as region E) that immediately flanks a cluster of five T3 response elements in the malic enzyme gene. Here, we have analyzed the binding of nuclear proteins to region E and investigated the mechanism by which region E enhances T3 responsiveness. In nuclear extracts from hepatocytes, region E binds heterodimeric complexes consisting of the homeodomain proteins PBX and MEIS1. Region E contains four consecutive PBX/MEIS1 half-sites. PBX-MEIS1 heterodimers bind the first and second half-sites, the third and fourth half-sites, and the first and fourth half-sites. The configuration conferring the greatest increase in T3 responsiveness consists of the first and fourth half-sites that are separated by 7 nucleotides. Stimulation of T3 response element functions by region E does not require the presence of additional malic enzyme sequences. In pull-down experiments, PBX1a and PBX1b specifically bind the nuclear T3 receptor-alpha, and this interaction is enhanced by the presence of T3. A T3 receptor-alpha region containing the DNA binding domain plus flanking sequences (amino acids 21-157) is necessary and sufficient for binding to PBX1a and PBX1b. These results indicate that PBX-MEIS1 complexes interact with nuclear T3 receptors to enhance T3 regulation of malic enzyme transcription in hepatocytes.
Collapse
Affiliation(s)
- Y Wang
- Department of Biochemistry, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
| | | | | |
Collapse
|