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Oglio R, Rodriguez C, Salvarredi L, Rossich L, Perona M, Dagrosa A, Juvenal G, Thomasz L. Selenium bioavailability modulates the sensitivity of thyroid cells to iodide excess. Chem Biol Interact 2024; 387:110810. [PMID: 38013145 DOI: 10.1016/j.cbi.2023.110810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 10/25/2023] [Accepted: 11/15/2023] [Indexed: 11/29/2023]
Abstract
INTRODUCTION Iodide is an essential micronutrient for the synthesis of thyroid hormones and its imbalance is involved in the origin of different thyroid pathological processes. Selenium (Se) is another essential trace element that contributes to thyroid preservation through the control of the redox homeostasis. Different studies have demonstrated that sodium-iodide-symporter (NIS) is downregulated in the presence of iodide excess and Se supplementation reverses this effect. We also demonstrated that NOX4-derived ROS are involved in NIS repression induced by iodide excess. The aim of this study was to investigate how Se bioavailability is decisive in the sensitivity to iodide excess on a differentiated rat thyroid cell line (FRTL-5). RESULTS We demonstrated that siRNA-mediated silencing of Nox4 suppressed AKT phosphorylation induced by iodide excess. Iodide increases TGF-β1 mRNA expression, AKT phosphorylation, ROS levels and decreases GPX1 and TXRND1 mRNAs expression while Se reversed these effects. Furthermore, iodide induced Nrf2 transcriptional activity only in Se-supplemented cultures, suggesting that Se positively influences Nrf2 activation and selenoenzyme response in FRTL-5. Se, also inhibited NF-κB phosphorylation induced by iodide excess. In addition, we found that iodide excess decreased total phosphatase activity and PTP1B and PTEN mRNA expression. Se supply restored only PTEN mRNA expression. Finally, we studied the 2-α-iodohexadecanal (2-IHD) effects since it has been proposed as intermediary of iodide action on thyroid autoregulation. 2-IHD stimulated PI3K/AKT activity and reduced NIS expression by a ROS-independent mechanism. Also, we found that 2-IHD increased TGF-β1 mRNA and TGF-β inhibitor (SB431542) reverses the 2-IHD inhibitory effect on NIS mRNA expression, suggesting that TGF-β1 signaling pathway could be involved. Although Se reduced 2-IHD-induced TGFB1 levels, it could not reverse its inhibitory effect on NIS expression. CONCLUSION Our study suggests that Se bioavailability may improve the expression of antioxidant genes through the activation of Nrf2, interfere in PI3K/AKT signaling and NIS expression by redox modulation.
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Affiliation(s)
- Romina Oglio
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires, Argentina
| | - Carla Rodriguez
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires, Argentina
| | - Leonardo Salvarredi
- FUESMEN, Mendoza, Argentina; Balseiro Institute, National University of Cuyo, Mendoza, Argentina
| | - Luciano Rossich
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires, Argentina
| | - Marina Perona
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires, Argentina; CONICET, Buenos Aires, Argentina
| | - Alejandra Dagrosa
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires, Argentina; CONICET, Buenos Aires, Argentina
| | - Guillermo Juvenal
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires, Argentina; CONICET, Buenos Aires, Argentina
| | - Lisa Thomasz
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires, Argentina; CONICET, Buenos Aires, Argentina.
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Romina O, Federico B, Leonardo S, Jennifer M, Carla R, Marina P, Alejandra D, Guillermo J, Lisa T. 6 Iodo-delta lactone inhibits angiogenesis in human HT29 colon adenocarcinoma xenograft. Prostaglandins Leukot Essent Fatty Acids 2022; 186:102507. [PMID: 36244213 DOI: 10.1016/j.plefa.2022.102507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 08/24/2022] [Accepted: 10/06/2022] [Indexed: 12/29/2022]
Abstract
INTRODUCTION Several studies have shown the antiproliferative effect of iodine and 5‑hydroxy-6 iodo-eicosatrienoic delta lactone (IL-δ) on diverse tissues. It was demonstrated that molecular iodine (I2) and IL-δ, but not iodide (I-), exerts anti-neoplastic actions in different cancers. The underlying mechanism through which IL-δ inhibits tumor growth remains unclear. The aim of this study was to analyze the effect of IL-δ on tumor growth and angiogenesis in human HT29 colorectal cancer xenografts. METHODOLOGY AND RESULTS HT29 cells were injected subcutaneously into the flanks of nude mice and IL-δ was i.p. injected at a dose of 15 μg three days a week. IL-δ treatment in HT29 xenografts showed time-dependent inhibition of tumor growth, decrease of mitosis and PCNA expression (p < 0.05), increase of P27 expression and Caspase 3 activity after 18 days of treatment (p < 0.05). To assess tumor Microvessel Densities (MVD), CD31 staining by immunohistochemistry was analyzed. IL-δ treatment decreased MVD by 17% and 30% after 18 and 30 days respectively (p < 0.05), as well as it decreased VEGF and VEGF-R2 expression (p < 0.05). Additionally, our findings demonstrated that IL-δ increased VEGF-R1 and Ang-1 mRNA levels (p < 0.01). CONCLUSION The antitumor efficacy of IL-δ in vivo involves inhibition of cell proliferation as well as induction of apoptosis. IL-δ has also anti-angiogenic effect associated with VEGF and VEGF-R2 downregulation followed by Ang-1 and VEGF-R1 increased expression. High levels of Ang-1 would contribute to mature vessel stabilization and maintenance while VEGF-R1 increase would produce anti-proliferative effect on endothelial cells.
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Affiliation(s)
- Oglio Romina
- Department of Radiobiology (CAC), National Comission of Atomic Energy (CNEA), Argentine
| | - Buschittari Federico
- Department of Radiobiology (CAC), National Comission of Atomic Energy (CNEA), Argentine
| | - Salvarredi Leonardo
- Department of Radiobiology (CAC), National Comission of Atomic Energy (CNEA), Argentine
| | | | - Rodriguez Carla
- Department of Radiobiology (CAC), National Comission of Atomic Energy (CNEA), Argentine
| | - Perona Marina
- Department of Radiobiology (CAC), National Comission of Atomic Energy (CNEA), Argentine; National Council of Scientific and Technical Research (CONICET), Argentine
| | - Dagrosa Alejandra
- Department of Radiobiology (CAC), National Comission of Atomic Energy (CNEA), Argentine; National Council of Scientific and Technical Research (CONICET), Argentine
| | - Juvenal Guillermo
- Department of Radiobiology (CAC), National Comission of Atomic Energy (CNEA), Argentine; National Council of Scientific and Technical Research (CONICET), Argentine
| | - Thomasz Lisa
- Department of Radiobiology (CAC), National Comission of Atomic Energy (CNEA), Argentine; National Council of Scientific and Technical Research (CONICET), Argentine.
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Oglio R, Salvarredi L, Rossich L, Copelli S, Pisarev M, Juvenal G, Thomasz L. Participation of NADPH 4 oxidase in thyroid regulation. Mol Cell Endocrinol 2019; 480:65-73. [PMID: 30316800 DOI: 10.1016/j.mce.2018.10.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 10/10/2018] [Accepted: 10/10/2018] [Indexed: 12/14/2022]
Abstract
Different factors are involved in thyroid function and proliferation such as thyrotropin (TSH), insulin, growth factors, iodide, etc. TSH and IGF1/insulin increase proliferation rate and stimulate genes involved in thyroid differentiation. In the present study, we analyse the physiological regulation of NOX4 expression by TSH, insulin and iodine, and the role of NOX4 on thyroid genes expression. Differentiated rat thyroid cells (FRTL-5) were incubated in the presence or absence of TSH/insulin and TTF2, PAX8, TPO, NIS, NOX4, TGFβ1, FOXO1/3 mRNA levels were examined by Real Time PCR. We showed that TSH and insulin repress NOX4 expression and appears to be inversely correlated with some thyroid genes. SiRNA targeted knockdown of NOX4 increased mRNA levels of TGFβ1, TPO, PAX8, TTF2, FOXO1 and FOXO3. A PI3K inhibitor (LY294002), increases the expression of NIS, TTF2 and FOXO1/3, however PI3K/AKT pathway does not regulate NOX4 expression. We observed that iodine increased NOX4 expression and knockdown of NOX4 reduced ROS and reversed the inhibitory effect of iodine on NIS, TPO, PAX8 and TTF2 expression. Our findings provide strong evidence that NOX4 could be a novel signaling modulator of TSH/insulin pathway and would have a critical role in the autoregulatory mechanism induced by iodine.
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Affiliation(s)
- Romina Oglio
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission Buenos Aires, 1429, Argentina.
| | - Leonardo Salvarredi
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission Buenos Aires, 1429, Argentina
| | - Luciano Rossich
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission Buenos Aires, 1429, Argentina
| | | | - Mario Pisarev
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission Buenos Aires, 1429, Argentina; CONICET, Argentina; Department of Human Biochemistry, University of Buenos Aires School of Medicine, Argentina
| | - Guillermo Juvenal
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission Buenos Aires, 1429, Argentina; CONICET, Argentina
| | - Lisa Thomasz
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission Buenos Aires, 1429, Argentina; CONICET, Argentina.
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Thomasz L, Oglio R, Salvarredi L, Perona M, Rossich L, Copelli S, Pisarev M, Juvenal G. Regulation of NADPH oxidase NOX4 by delta iodolactone (IL-δ) in thyroid cancer cells. Mol Cell Endocrinol 2018; 470:115-126. [PMID: 28993239 DOI: 10.1016/j.mce.2017.10.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 10/04/2017] [Accepted: 10/04/2017] [Indexed: 11/18/2022]
Abstract
INTRODUCTION Iodine is not used only by the thyroid to synthesize thyroid hormones but also directly influences a number of thyroid parameters such as thyroid proliferation and function. Several iodinated lipids, biosynthesized by the thyroid, were postulated as intermediaries in the action of iodide. Among these, iodolactone (IL-δ) and 2-iodohexadecanal (2-IHDA) have shown to inhibit several thyroid parameters. The antiproliferative effect of IL-δ is not restricted to the thyroid gland. IL-δ exhibits anti-tumor properties in breast cancer, neuroblastoma, glioblastoma, melanoma and lung carcinoma cells suggesting that IL-δ could be used as a chemotherapeutic agent. Moreover in a colon cancer cell line (HT-29), IL-δ induced cell death, and this effect was mediated by reactive oxygen species (ROS) generation. The aim of the present study was to analyze the sources of reactive oxygen species induced by IL-δ and to explore the contribution of ROS induced by IL-δ on cell proliferation and apoptosis. METHODOLOGY AND RESULTS Cancer thyroid follicular (WRO) and papilar (TPC-1) cells lines were treated with IL-δ. Proliferation and apoptosis was analyzed. IL-δ caused a significant loss of cell viability on WRO and TPC-1 cells in a concentration dependent manner and induced apoptosis after 3 h of treatment. Furthermore, IL-δ (10 μM) increased ROS production (39% WRO and 20% TPC-1). The concomitant treatment of WRO and TPC-1 cells with Trolox or NAC plus IL-δ abrogated the augment of ROS induced by IL-δ exposure. Additionally Trolox and NAC reversed the effect of IL-δ on cell proliferation and apoptosis. Only in WRO cells IL-δ upregulates NADPH oxidase NOX4 expression, and siRNA targeted knock-down of NOX4 attenuates ROS production, apoptosis (p < 0.05) and the inhibitory effect of IL-δ on cell proliferation and PCNA expression (p < 0.05). CONCLUSIONS The antiproliferative and pro-apoptotic effect of IL-δ is mediated by different mechanisms and pathway involving different sources of ROS generation depending on the cellular context.
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Affiliation(s)
- Lisa Thomasz
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires 1429, Argentina; CONICET, Argentina.
| | - Romina Oglio
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires 1429, Argentina
| | - Leonardo Salvarredi
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires 1429, Argentina
| | - Marina Perona
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires 1429, Argentina; CONICET, Argentina
| | - Luciano Rossich
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires 1429, Argentina
| | | | - Mario Pisarev
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires 1429, Argentina; CONICET, Argentina
| | - Guillermo Juvenal
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, Buenos Aires 1429, Argentina; CONICET, Argentina.
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Liang X, Feng Y, Lin L, Abeysekera IR, Iqbal U, Wang T, Wang Y, Yao X. Thyroid function alterations attributed to high iodide supplementation in maternal rats and their offspring. J Trace Elem Med Biol 2018; 47:89-97. [PMID: 29544812 DOI: 10.1016/j.jtemb.2018.01.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Revised: 01/21/2018] [Accepted: 01/31/2018] [Indexed: 02/01/2023]
Abstract
OBJECTIVE Our aim was to investigate thyroid function alterations attributed to high iodide supplementation in maternal rats and their offspring. METHODS Depending on their iodide intake, the pregnant rats were randomly divided into three groups: normal iodide intake (NI), 10 times high iodide intake (10 HI) and 100 times high iodide intake (100 HI) groups. Iodine concentration in the urine and maternal milk; iodine content and mitochondrial superoxide production; expression of TRα1, TRβ1, NIS and Dio1 in both the thyroid and mammary glands were all measured. The offspring were exposed to different iodide-containing water (NI, 10 HI and 100 HI) from weaning to postnatal day 180 (PN180). Serum thyroid hormone levels were measured in both maternal rats and their offspring. RESULTS Iodine concentration in the urine and maternal milk, as well as iodine content in the thyroid and mammary glands was significantly increased in both the 10 HI and 100 HI groups (p < .05). In the 100 HI group of maternal rats, low FT3 levels, high FT4, TPOAb and TgAb levels were detected. In addition, an increased mitochondrial superoxide production and decreased expression of TRα1, TRβ1, NIS and Dio1 in the thyroid and mammary glands was found (p < .05). A positive staining of CD4+ that co-localized with TRβ1 in the infiltrated cells within the thyroid follicles was observed. At PN180 in the offspring, the FT3 and FT4 levels showed a significant decrease, while the levels of serum TSH, TPOAb and TgAb were significantly increased in both 10 HI and 100 HI groups (p < .05). CONCLUSION In maternal rats, although normal thyroid function can be maintained following 10 HI, thyroiditis can be induced following 100 HI on lactation days 7, 14, and 21. In the offspring at PN180, hypothyroidism complicated with thyroiditis can occur in both the 10 HI and 100 HI groups.
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Affiliation(s)
- Xue Liang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China.
| | - Yanni Feng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China.
| | - Laixiang Lin
- Key Laboratory of Hormones and Development (Ministry of Health), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin 300070, China.
| | - Iruni Roshanie Abeysekera
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China.
| | - Umar Iqbal
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China.
| | - Tingting Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China.
| | - Ying Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China.
| | - Xiaomei Yao
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China.
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Rossich LE, Thomasz L, Nicola JP, Nazar M, Salvarredi LA, Pisarev M, Masini-Repiso AM, Christophe-Hobertus C, Christophe D, Juvenal GJ. Effects of 2-iodohexadecanal in the physiology of thyroid cells. Mol Cell Endocrinol 2016; 437:292-301. [PMID: 27568464 DOI: 10.1016/j.mce.2016.08.036] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 08/22/2016] [Accepted: 08/22/2016] [Indexed: 10/21/2022]
Abstract
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, 2-iodohexadecanal (2-IHDA) 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 2-IHDA on thyroid cell physiology. For this purpose, FRTL-5 thyroid cells were incubated with the two compounds during 24 or 48 h and several thyroid parameters were evaluated such as: iodide uptake, intracellular calcium and H2O2 levels. To further explore the molecular mechanism involved in 2-IHDA action, transcript and protein levels of genes involved in thyroid hormone biosynthesis, as well as the transcriptional expression of these genes were evaluated in the presence of iodide and 2-IHDA. The results obtained indicate that 2-IHDA reproduces the action of excess iodide on the "Wolff-Chaikoff" effect as well as on thyroid specific genes transcription supporting its role in thyroid autoregulation.
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Affiliation(s)
- Luciano E Rossich
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, CONICET, Buenos Aires, Argentina
| | - Lisa Thomasz
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, CONICET, Buenos Aires, Argentina
| | - Juan P Nicola
- Department of Clinical Biochemistry, School of Chemical Sciences, National University of Cordoba, CONICET, Buenos Aires, Argentina
| | - Magali Nazar
- Department of Clinical Biochemistry, School of Chemical Sciences, National University of Cordoba, CONICET, Buenos Aires, Argentina
| | - Leonardo A Salvarredi
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, CONICET, Buenos Aires, Argentina
| | - Mario Pisarev
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, CONICET, Buenos Aires, Argentina; Department of Human Biochemistry, University of Buenos Aires School of Medicine, CONICET, Buenos Aires, Argentina
| | - Ana M Masini-Repiso
- Department of Clinical Biochemistry, School of Chemical Sciences, National University of Cordoba, CONICET, Buenos Aires, Argentina
| | | | | | - Guillermo J Juvenal
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission, CONICET, Buenos Aires, Argentina.
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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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Arriagada AA, Albornoz E, Opazo MC, Becerra A, Vidal G, Fardella C, Michea L, Carrasco N, Simon F, Elorza AA, Bueno SM, Kalergis AM, Riedel CA. Excess iodide induces an acute inhibition of the sodium/iodide symporter in thyroid male rat cells by increasing reactive oxygen species. Endocrinology 2015; 156:1540-51. [PMID: 25594695 PMCID: PMC5393323 DOI: 10.1210/en.2014-1371] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Na+/I- symporter (NIS) mediates iodide (I-) uptake in the thyroid gland, the first and rate-limiting step in the biosynthesis of the thyroid hormones. The expression and function of NIS in thyroid cells is mainly regulated by TSH and by the intracellular concentration of I-. High doses of I- for 1 or 2 days inhibit the synthesis of thyroid hormones, a process known as the Wolff-Chaikoff effect. The cellular mechanisms responsible for this physiological response are mediated in part by the inhibition of I- uptake through a reduction of NIS expression. Here we show that inhibition of I- uptake occurs as early as 2 hours or 5 hours after exposure to excess I- in FRTL-5 cells and the rat thyroid gland, respectively. Inhibition of I- uptake was not due to reduced NIS expression or altered localization in thyroid cells. We observed that incubation of FRTL-5 cells with excess I- for 2 hours increased H2O2 generation. Furthermore, the inhibitory effect of excess I- on NIS-mediated I- transport could be recapitulated by H2O2 and reverted by reactive derived oxygen species scavengers. The data shown here support the notion that excess I- inhibits NIS at the cell surface at early times by means of a posttranslational mechanism that involves reactive derived oxygen species.
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Affiliation(s)
- Alejandro A Arriagada
- Facultad de Ciencias Biológicas y Medicina (A.A.A., E.A., M.C.O., A.B., G.V., F.S., A.A.E., C.A.R.), Universidad Andrés Bello, República 217, Piso 4, Santiago, Chile; Millennium Institute on Immunology and Immunotherapy (A.A.A., E.A., M.C.O., A.B., G.V., C.F., L.M., F.S., A.A.E., S.M.B., A.M.K., C.A.R.), Departamento de Endocrinología (C.F.) and Departamento de Reumatología (A.M.K.), Facultad de Medicina, and Departamento de Genética Molecular y Microbiología (S.M.B., A.M.K.), Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, 8331010 Santiago, Chile; Center for Molecular Studies of the Cell (L.M.), ICBM, Facultad de Medicina, Universidad De Chile, 6640750 Santiago, Chile; Department of Cellular and Molecular Physiology (N.C.), Yale School of Medicine, New Haven, Connecticut 06520; and INSERM Unité Mixte de Recherche 1064 (S.M.B., A.M.K., C.A.R.), 44000 Nantes, France
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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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11
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Olvera-Caltzontzin P, Delgado G, Aceves C, Anguiano B. Iodine uptake and prostate cancer in the TRAMP mouse model. Mol Med 2013; 19:409-16. [PMID: 24306422 DOI: 10.2119/molmed.2013.00093] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 11/07/2013] [Indexed: 01/06/2023] Open
Abstract
Iodine supplementation exerts antitumor effects in several types of cancer. Iodide (I⁻) and iodine (I₂) reduce cell proliferation and induce apoptosis in human prostate cancer cells (LNCaP and DU-145). Both chemical species decrease tumor growth in athymic mice xenografted with DU-145 cells. The aim of this study was to analyze the uptake and effects of iodine in a preclinical model of prostate cancer (transgenic adenocarcinoma of the mouse prostate [TRAMP] mice/SV40-TAG antigens), which develops cancer by 12 wks of age. ¹²⁵I⁻ and ¹²⁵I₂ uptake was analyzed in prostates from wild-type and TRAMP mice of 12 and 24 wks in the presence of perchlorate (inhibitor of the Na⁺/I⁻ symporter [NIS]). NIS expression was quantified by quantitative polymerase chain reaction (qPCR). Mice (6 wks old) were supplemented with 0.125 mg I⁻ plus 0.062 mg I₂/mouse/day for 12 or 24 wks. The weight of the genitourinary tract (GUT), the number of acini with lesions, cell proliferation (levels of proliferating cell nuclear antigen [PCNA] by immunohistochemistry), p53 and p21 expression (by qPCR) and apoptosis (relative amount of nucleosomes by enzyme-linked immunosorbent assay) were evaluated. In both age-groups, normal and tumoral prostates take up both forms of iodine, but only I⁻ uptake was blocked by perchlorate. Iodine supplementation prevented the overexpression of NIS in the TRAMP mice, but had no effect on the GUT weight, cell phenotype, proliferation or apoptosis. In TRAMP mice, iodine increased p53 expression but had no effect on p21 (a p53-dependent gene). Our data corroborate NIS involvement in I⁻ uptake and support the notion that another transporter mediates I₂ uptake. Iodine did not prevent cancer progression. This result could be explained by a strong inactivation of the p53 pathway by TAG antigens.
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Affiliation(s)
- Paloma Olvera-Caltzontzin
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro, México
| | - Guadalupe Delgado
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro, México
| | - Carmen Aceves
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro, México
| | - Brenda Anguiano
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro, México
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12
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Thomasz L, Oglio R, Rossich L, Villamar S, Perona M, Salvarredi L, Dagrosa A, Pisarev MA, Juvenal GJ. 6 Iodo-δ-lactone: a derivative of arachidonic acid with antitumor effects in HT-29 colon cancer cells. Prostaglandins Leukot Essent Fatty Acids 2013; 88:273-80. [PMID: 23375358 DOI: 10.1016/j.plefa.2013.01.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 12/26/2012] [Accepted: 01/04/2013] [Indexed: 01/21/2023]
Abstract
BACKGROUND IL-δ (5-hydroxy-6 iodo-8,11,14-eicosatrienoic delta lactone) an iodinated arachidonic acid (AA) derivative, is one of the iodolipids biosynthesized by the thyroid. Although IL-δ regulates several thyroid parameters such as cell proliferation and goiter growth it was found that this iodolipid inhibits the growth of other non thyroid cell lines. OBJECTIVES To study the effect of IL-δ on cell proliferation and apoptosis in the colon cancer cell line HT-29. RESULTS Treatment with IL-δ reduced cell viability in a concentration-dependent manner: 1μM 20%, 5μM 25%, 10μM 31%, 50μM 47% and caused a significant decrease of PCNA expression (25%). IL-δ had pro-apoptotic effects, evidenced by morphological features of programmed cell death such as pyknosis, karyorrhexis, cell shrinkage and cell blebbing observed by fluorescence microscopy, and an increase in caspase-3 activity and in Bax/Bcl-2 ratio (2.5 after 3h of treatment). Furthermore, IL-δ increased ROS production (30%) and lipid peroxidation levels (19%), suggesting that apoptosis could be a result of increased oxidative stress. A maximum increase in c-fos and c-jun protein expression in response to IL-δ was observed 1h after initiation of the treatment. IL-δ also induced a tumour growth delay of 70% compared to the control group in NIH nude mice implanted with HT-29 cells. CONCLUSION Our study shows that IL-δ inhibits cell growth and induces apoptosis in the colon cancer cell line, HT-29 and opens the possibility that IL-δ could be a potential useful chemotherapy agent.
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Affiliation(s)
- Lisa Thomasz
- Nuclear Biochemistry Division, Argentine National Atomic Energy Commission Buenos Aires 1429, Argentina
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13
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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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14
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Aranda N, Sosa S, Delgado G, Aceves C, Anguiano B. Uptake and antitumoral effects of iodine and 6-iodolactone in differentiated and undifferentiated human prostate cancer cell lines. Prostate 2013; 73:31-41. [PMID: 22576883 DOI: 10.1002/pros.22536] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 04/18/2012] [Indexed: 11/08/2022]
Abstract
BACKGROUND Evidence indicates that iodine per se could be implicated in the physiology of several organs that can internalize it. In thyroid and breast cancer, iodine treatments inhibit cell proliferation and induce apoptosis through a direct (mitochondria) and/or indirect effect (iodolipid generation). Here, we determined the uptake of iodide (I(-) ) and iodine (I(2) ), as well as the antiproliferative and apoptotic effects of 6-iodolactone (6-IL) and both forms of iodine in human prostate cells lines. METHODS Non-cancerous (RWPE-1) and cancerous (LNCaP, DU-145) cells, as well as nude mice xenotransplanted with DU-145 cells were used as cancer models. Iodine uptake was analyzed with radioactive tracers, transporter expression by qRT-PCR, cell proliferation by blue trypan, apoptosis by enzyme immunoassay or fluorescence, BAX and BCL-2 by western-blot, and caspsase 3 by enzymatic assay. RESULTS All three cell lines take up both forms of iodine. In RWPE-1 cells, I(-) uptake depends on the Na(+) /I(-) symporter (NIS), whereas it was independent of NIS in LNCaP and DU-145 cells. Antiproliferative effects of iodine and 6-IL were dose and time dependent; RWPE-1 was most sensitive to I(-) and 6-IL, whereas LNCaP was more sensitive to I(2) . In the three cell lines both forms of iodine activated the intrinsic apoptotic pathway (increasing the BAX/BCL-2 index and caspases). Iodine supplementation impaired growth of the DU-145 tumor in nude mice. CONCLUSION Normal and cancerous prostate cells can take up iodine, and depending on the chemical form, it exerts antiproliferative and apoptotic effects both in vitro and in vivo.
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Affiliation(s)
- Nuri Aranda
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, Qro., Mexico
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15
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Leoni SG, Kimura ET, Santisteban P, De la Vieja A. Regulation of thyroid oxidative state by thioredoxin reductase has a crucial role in thyroid responses to iodide excess. Mol Endocrinol 2011; 25:1924-35. [PMID: 21903721 DOI: 10.1210/me.2011-0038] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The phenomenon that supraphysiological doses of iodide (I(-)) temporarily inhibit thyroid hormone synthesis is known as thyroid iodide autoregulation. Recovery of thyroid function has been attributed to sodium-iodide symporter (NIS) inhibition, but the diversity of available data makes it difficult to reach definitive conclusions. Iodide excess induces reactive oxygen species production and cell toxicity. However, the roles of the oxidative state of the cell and antioxidant selenoproteins in I(-) autoregulation have never been explored. Here we analyze the effects of high I(-) doses in rat thyroids and in PCCl3 cells in the period comprising I(-) autoregulation (i.e. 0-72 h after I(-) administration), focusing on NIS expression, redox state, and the expression and activity of selenoproteins. Our results show that NIS mRNA inhibition by I(-) does not occur at the transcriptional level, because neither NIS promoter activity nor Pax8 expression or its binding to DNA was modulated. Because I(-) uptake was inhibited much earlier than NIS protein, and no effect was observed on its subcellular localization, we suggest that I(-) is inhibiting NIS in the plasma membrane. The increased reactive oxygen species production leads to an increase in thioredoxin reductase mRNA levels and enzyme activity, which reduces the oxidative stress. Inhibition of thioredoxin reductase at either gene expression or activity levels prevented NIS recovery, thus illustrating a new role played by this selenoprotein in the regulation of cell homeostasis and consequently in I(-) autoregulation.
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Affiliation(s)
- Suzana G Leoni
- Instituto de Investigaciones Biome´ dicas “Alberto Sols” Consejo Superior de Investigaciones Científicas y Universidad Auto´ noma de Madrid, Spain
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16
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Thomasz L, Oglio R, Randi AS, Fernandez M, Dagrosa MA, Cabrini RL, Juvenal GJ, Pisarev MA. Biochemical changes during goiter induction by methylmercaptoimidazol and inhibition by delta-iodolactone in rat. Thyroid 2010; 20:1003-13. [PMID: 20825298 DOI: 10.1089/thy.2009.0257] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND We have demonstrated that the administration of delta-iodolactone (i.e., 5-iodo-delta lactone) of arachidonic acid (IL-delta), a mediator in thyroid autoregulation, prevents goiter induction by methylmercaptoimidazol (MMI) in rats. Other studies have shown that transforming growth factor beta-1 (TGF-beta1) mimics some of the actions of excess iodide, but its participation in autoregulation is disputed. The present studies were performed to test the hypotheses that IL-delta decreases thyroid growth by inhibition of cell proliferation and/or by stimulation of apoptosis due to oxidative stress, that TGF-beta is stimulated by an excess of iodide and by IL-delta, and that c-Myc and c-Fos expression are upregulated during goiter induction and downregulated during goiter inhibition. METHODS Rats were treated with MMI alone or together with iodide or IL-delta. Thyroid weight, cell number, cell proliferation, apoptosis, and oxidative stress were determined. Proliferating cell nuclear antigen (PCNA), TGF-beta1, TGF-beta3, c-Myc, and c-Fos were measured by Western blot. RESULTS MMI caused a progressive increase in thyroid weight accompanied by an increase in cell number, asymmetry of the ploidy histograms, and PCNA, c-Fos, and c-Myc expression. In addition, an early increase of apoptosis was observed. Peroxides as well as glutathione peroxidase and catalase activities were also increased in goitrous animals. The inhibitory action of IL-delta on goiter formation was accompanied by the inhibition of cell proliferation evidenced by a significant decrease in cell number, PCNA expression, and asymmetry of the ploidy histograms. A transient stimulation of apoptosis after 7 days of treatment was also observed. MMI administration stimulated TGF-beta1 but not TGF-beta3 synthesis. IL-delta alone caused a slight increase of TGF-beta3 but not TGF-beta1, whereas potassium iodide (KI) stimulated both isoforms and MMI reversed KI effect on TGF-beta1 expression but not on TGF-beta3. CONCLUSIONS The goiter inhibitory action of IL-delta is due to the inhibition of cell proliferation and the transient stimulation of apoptosis. This latter action does not involve oxidative stress. TGF-beta1 does not play a role in the autoregulatory pathway mediated by IL-delta. Iodide stimulates TGF-beta3 without the need of being organified. These results suggest that there may be more than one pathway involved in the autoregulatory mechanism.
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Affiliation(s)
- Lisa Thomasz
- Nuclear Biochemistry Division, Department of Radiobiology, National Atomic Energy Commission, Buenos Aires, Argentina
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