scholarly journals The Flavonoid Quercetin Induces AP-1 Activation in FRTL-5 Thyroid Cells

Antioxidants ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 112 ◽  
Author(s):  
Cesidio Giuliani
Keyword(s):  
Binding Site ◽  
Thyroid Function ◽  
Thyroid Cell ◽  
Consensus Binding Site ◽  
Thyroid Cells ◽  
Basal Activity ◽  
Reporter Vector ◽  
Rat Thyroid

Previous studies have shown that quercetin inhibits thyroid function both in vitro and in vivo. An attempt to evaluate the effect of quercetin at the promoter level of the thyroid-specific genes led to the observation that this compound induces the basal activity of the reporter vector. Therefore, the action of quercetin has been evaluated on the basal activity of several reporter vectors: The PGL3 basic, promoter and control vectors from Promega, and a pSV-based chloramphenicol acetyltransferase (CAT) reporter vector. In the Fisher Rat Thyroid cell Line FRTL-5 thyroid cells transiently transfected, quercetin 10 μM increased the basal activity of all the reporter vectors evaluated, although the degree of the effect was significantly different among them. The analysis of the difference among the regulatory regions of these vectors identified the activator protein 1 (AP-1) binding site as one of the potential sites involved in the quercetin effect. Electromobility shift assay experiments showed that the treatment with quercetin induced the binding of a protein complex to an oligonucleotide containing the AP-1 consensus binding site. This is the first study showing an effect of quercetin on AP-1 activity in thyroid cells. Further studies are in progress to understand the role of AP-1 activation in the effects of quercetin on thyroid function.

scholarly journals Acrylamide does not induce tumorigenesis or major defects in mice in vivo

2008 ◽  
Vol 198 (2) ◽  
pp. 301-307 ◽  
Author(s):  
Ling Jin ◽  
Vanessa Chico-Galdo ◽  
Claude Massart ◽  
Christine Gervy ◽  
Viviane De Maertelaere ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Chronic Administration ◽  
Serum Levels ◽  
Human Thyroid ◽  
Thyroid Cell ◽  
Thyroid Cells ◽  
Hormone Synthesis ◽  
Rat Thyroid

Chronic administration of acrylamide has been shown to induce thyroid tumors in rat. In vitro acrylamide also causes DNA damage, as demonstrated by the comet assay, in various types of cells including human thyroid cells and lymphocytes, as well as rat thyroid cell lines. In this work, mice were administered acrylamide in their drinking water in doses comparable with those used in rats, i.e., around 3–4 mg/kg per day for mice treated 2, 6, and 8 months. Some of the mice were also treated with thyroxine (T4) to depress the activity of the thyroid. Others were treated with methimazole that inhibits thyroid hormone synthesis and consequently secretion and thus induces TSH secretion and thyroid activation. These moderate treatments were shown to have their known effect on the thyroid (e.g. thyroid hormone and thyrotropin serum levels, thyroid gland morphology…). Besides, T4 induced an important polydipsia and degenerative hypertrophy of adrenal medulla. Acrylamide exerted various discrete effects and at high doses caused peripheral neuropathy, as demonstrated by hind-leg paralysis. However, it did not induce thyroid tumorigenesis. These results show that the thyroid tumorigenic effects of acrylamide are not observed in another rodent species, the mouse, and suggest the necessity of an epidemiological study in human to conclude on a public health policy.

Anoctamin-1/TMEM16A is the major apical iodide channel of the thyrocyte

2014 ◽  
Vol 307 (12) ◽  
pp. C1102-C1112 ◽  
Author(s):  
L. Twyffels ◽  
A. Strickaert ◽  
M. Virreira ◽  
C. Massart ◽  
J. Van Sande ◽  
...  
Keyword(s):  
Cell Lines ◽  
Apical Membrane ◽  
Specific Inhibitor ◽  
Anion Channel ◽  
Thyroid Cell ◽  
Anoctamin 1 ◽  
Thyroid Cells ◽  
Rat Thyroid

Iodide is captured by thyrocytes through the Na+/I− symporter (NIS) before being released into the follicular lumen, where it is oxidized and incorporated into thyroglobulin for the production of thyroid hormones. Several reports point to pendrin as a candidate protein for iodide export from thyroid cells into the follicular lumen. Here, we show that a recently discovered Ca2+-activated anion channel, TMEM16A or anoctamin-1 (ANO1), also exports iodide from rat thyroid cell lines and from HEK 293T cells expressing human NIS and ANO1. The Ano1 mRNA is expressed in PCCl3 and FRTL-5 rat thyroid cell lines, and this expression is stimulated by thyrotropin (TSH) in rat in vivo, leading to the accumulation of the ANO1 protein at the apical membrane of thyroid follicles. Moreover, ANO1 properties, i.e., activation by intracellular calcium (i.e., by ionomycin or by ATP), low but positive affinity for pertechnetate, and nonrequirement for chloride, better fit with the iodide release characteristics of PCCl3 and FRTL-5 rat thyroid cell lines than the dissimilar properties of pendrin. Most importantly, iodide release by PCCl3 and FRTL-5 cells is efficiently blocked by T16Ainh-A01, an ANO1-specific inhibitor, and upon ANO1 knockdown by RNA interference. Finally, we show that the T16Ainh-A01 inhibitor efficiently blocks ATP-induced iodide efflux from in vitro-cultured human thyrocytes. In conclusion, our data strongly suggest that ANO1 is responsible for most of the iodide efflux across the apical membrane of thyroid cells.

scholarly journals Regulation of thymosin beta10 expression by TSH and other mitogenic signals in the thyroid gland and in cultured thyrocytes

1999 ◽  
pp. 597-607 ◽  
Author(s):  
G Viglietto ◽  
D Califano ◽  
P Bruni ◽  
G Baldassarre ◽  
MT Vento ◽  
...  
Keyword(s):  
Thyroid Gland ◽  
Actin Polymerization ◽  
Mrna Level ◽  
Thyroid Cell ◽  
Dependent Manner ◽  
Follicular Cells ◽  
Thyroid Cells ◽  
Rat Thyroid

OBJECTIVE: To investigate the expression of thymosin beta10 - a small conserved acidic protein involved in the inhibition of actin polymerization - in human and experimental thyroid goiters as well as the regulation exerted by TSH on thymosin beta10 expression in thyroid follicular cells both in vivo and in vitro. DESIGN: To this aim, we have used 5 bioptic specimens from patients affected by thyroid goiter, a well known experimental model of thyroid goitrogenesis (rat fed with the drug propylthiouracil) and a cultured rat thyroid cell line (PC Cl 3 cells) as a model system. RESULTS: We report that the mRNA expression of thymosin beta10 is markedly enhanced in human goiters compared with normal thyroid. In vivo results showed that the steady-state level of thymosin beta10 mRNA is up-regulated in the thyroid gland of propylthiouracil-fed rats in parallel with follicular cell proliferation: iodide administration to goitrous rats, which induced a marked involution of thyroid hyperplasia, reduced the mRNA level of thymosin beta10. Finally, in vitro studies showed that in cultured rat thyrocytes, the expression of thymosin beta10 mRNA is induced in a time- and dose-dependent manner by the activation of pathways which are mitogenic for thyroid cells (i.e. the protein kinase (PK) A and PKC pathways). CONCLUSION: Taken together, the findings reported here demonstrate that thymosin beta10 expression is regulated by extracellular signals that stimulate growth of thyroid cells both in vitro and in vivo, and suggest a role for this protein in thyroid diseases characterized by proliferation of follicular cells.

scholarly journals Trace Amine-Associated Receptor 1 Trafficking to Cilia of Thyroid Epithelial Cells

Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1518
Author(s):  
Maria Qatato ◽  
Vaishnavi Venugopalan ◽  
Alaa Al-Hashimi ◽  
Maren Rehders ◽  
Aaron D. Valentine ◽  
...  
Keyword(s):  
Cell Surface ◽  
Cell Lines ◽  
Human Thyroid ◽  
Apical Plasma Membrane ◽  
Thyroid Cell ◽  
Thyroid Cells ◽  
Trace Amine ◽  
Rat Thyroid

Trace amine-associated receptor 1 (rodent Taar1/human TAAR1) is a G protein-coupled receptor that is mainly recognized for its functions in neuromodulation. Previous in vitro studies suggested that Taar1 may signal from intracellular compartments. However, we have shown Taar1 to localize apically and on ciliary extensions in rodent thyrocytes, suggesting that at least in the thyroid, Taar1 may signal from the cilia at the apical plasma membrane domain of thyrocytes in situ, where it is exposed to the content of the follicle lumen containing putative Taar1 ligands. This study was designed to explore mouse Taar1 (mTaar1) trafficking, heterologously expressed in human and rat thyroid cell lines in order to establish an in vitro system in which Taar1 signaling from the cell surface can be studied in future. The results showed that chimeric mTaar1-EGFP traffics to the apical cell surface and localizes particularly to spherical structures of polarized thyroid cells, procilia, and primary cilia upon serum-starvation. Moreover, mTaar1-EGFP appears to form high molecular mass forms, possibly homodimers and tetramers, in stably expressing human thyroid cell lines. However, only monomeric mTaar1-EGFP was cell surface biotinylated in polarized human thyrocytes. In polarized rat thyrocytes, mTaar1-EGFP is retained in the endoplasmic reticulum, while cilia were reached by mTaar1-EGFP transiently co-expressed in combination with an HA-tagged construct of the related mTaar5. We conclude that Taar1 trafficking to cilia depends on their integrity. The results further suggest that an in vitro cell model was established that recapitulates Taar1 trafficking in thyrocytes in situ, in principle, and will enable studying Taar1 signaling in future, thus extending our general understanding of its potential significance for thyroid autoregulation.

scholarly journals The Human Candidate Tumor Suppressor Gene HIC1 Recruits CtBP through a Degenerate GLDLSKK Motif

2002 ◽  
Vol 22 (13) ◽  
pp. 4890-4901 ◽  
Author(s):  
Sophie Deltour ◽  
Sébastien Pinte ◽  
Cateline Guerardel ◽  
Bohdan Wasylyk ◽  
Dominique Leprince
Keyword(s):  
Binding Site ◽  
Transcriptional Repression ◽  
Histone Deacetylases ◽  
Trichostatin A ◽  
Suppressor Gene ◽  
Close Relative ◽  
Consensus Binding Site ◽  
Candidate Tumor Suppressor Gene

ABSTRACT HIC1 (hypermethylated in cancer) and its close relative HRG22 (HIC1-related gene on chromosome 22) encode transcriptional repressors with five C2H2 zinc fingers and an N-terminal BTB/POZ autonomous transcriptional repression domain that is unable to recruit histone deacetylases (HDACs). Alignment of the HIC1 and HRG22 proteins from various species highlighted a perfectly conserved GLDLSKK/R motif highly related to the consensus CtBP interaction motif (PXDLSXK/R), except for the replacement of the virtually invariant proline by a glycine. HIC1 strongly interacts with mCtBP1 both in vivo and in vitro through this conserved GLDLSKK motif, thus extending the CtBP consensus binding site. The BTB/POZ domain does not interact with mCtBP1, but the dimerization of HIC1 through this domain is required for the interaction with mCtBP1. When tethered to DNA by fusion with the Gal4 DNA-binding domain, the HIC1 central region represses transcription through interactions with CtBP in a trichostatin A-sensitive manner. In conclusion, our results demonstrate that HIC1 mediates transcriptional repression by both HDAC-independent and HDAC-dependent mechanisms and show that CtBP is a HIC1 corepressor that is recruited via a variant binding site.

scholarly journals Differential Interactions between Th1/Th2, Th1/Th3, and Th2/Th3 Cytokines in the Regulation of Thyroperoxidase and Dual Oxidase Expression, and of Thyroglobulin Secretion in Thyrocytes in Vitro

Endocrinology ◽  
2008 ◽  
Vol 149 (4) ◽  
pp. 1534-1542 ◽  
Author(s):  
Sylvie Poncin ◽  
Benoit Lengelé ◽  
Ides M. Colin ◽  
Anne-Catherine Gérard
Keyword(s):  
Thyroid Function ◽  
Interferon Γ ◽  
Thyroid Cell ◽  
Dual Oxidase ◽  
Th1 Cytokine ◽  
Glandular Atrophy ◽  
Rat Thyroid ◽  
Th1 Cytokines ◽  
The Impact

Hypothyroidism, together with glandular atrophy, is the usual outcome of destructive autoimmune thyroiditis. The impairment in the thyroid function results either from cell destruction or from Th1 cytokine-induced alteration in hormonogenesis. Here, we investigated the impact of the local immune context on the thyroid function. We used two rat thyroid cell lines (PCCL3 and FRTL-5) and human thyrocytes incubated with IL-1α/interferon (IFN) γ together with IL-4, a Th2 cytokine, or with TGF-β, or IL-10, two Th3 cytokines. We first observed that IL-4 totally blocked IL-1α/interferon γ-induced alteration in dual oxidase and thyroperoxidase expression, and in thyroglobulin secretion. By contrast, TGF-β and IL-10 had no such effect. They rather repressed thyrocyte function as do Th1 cytokines. In addition, IL-4 blocked IL-10-induced repression of thyrocyte function, but not that induced by TGF-β. In conclusion, Th1 cytokine- and IL-10-induced local inhibitory actions on thyroid function can be totally overturned by Th2 cytokines. These data provide new clues about the influence of the immune context on thyrocyte function.

2,3′,4,4′,5-Pentachlorobiphenyl Induced Thyrocyte Autophagy by Promoting Calcium Influx via Store-Operated Ca2+ Entry

2020 ◽  
Vol 177 (2) ◽  
pp. 483-493
Author(s):  
Li Wang ◽  
Wenli Xu ◽  
Qi Zhou ◽  
Bojin Xu ◽  
Yunlu Sheng ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Calcium Influx ◽  
Underlying Mechanism ◽  
Laser Scanning Confocal Microscopy ◽  
Thyroid Cell ◽  
Dependent Manner ◽  
Class Iii ◽  
Rat Thyroid

Abstract PCB118, a 2,3′,4,4′,5-pentachlorobiphenyl, has been shown to destroy thyroidal ultrastructure and induce thyrocyte autophagy. Previously, we reported that PCB118 promoted autophagosome formation in vivo and in vitro, but more details remain to be revealed. To explore the underlying mechanism by which PCB118 regulates thyrocyte autophagy, Fischer rat thyroid cell line-5 (FRTL-5) cells were exposed to different doses of PCB118 at 0, 0.25, 2.5, and 25 nM for 0–48 h. Western blot analysis of autophagy-related proteins P62, BECLIN1, and LC3 demonstrated that PCB118 induced autophagy formation in dose- and time-dependent manner. Moreover, laser scanning confocal microscopy and flow cytometry showed PCB118 treatment led to time- and dose-dependent increase in intracellular calcium concentration ([Ca2+]i). Additionally, PCB118 promoted store-operated Ca2+ entry (SOCE) channel followed by significant increase of ORAI1 and STIM1 protein levels. On the other hand, PCB118 induced thyroidal autophagy via class III β-tubulin (TUBB3)/death-associated protein kinase 2 (DAPK2)/myosin regulatory light chain (MRLC)/autophagy-related 9A (ATG9A) pathway in FRTL-5 cells. Pretreatment with SOCE inhibitor SKF96365 reduced cytosolic Ca2+, ORAI1, STIM1, and BECLIN1 levels as well as LC3 II/LC3 I ratio, while increased P62 expression. SKF96365 also inhibited TUBB3/DAPK2/MRLC/ATG9A pathway in FRTL-5 cells treated by PCB118. Our results provide evidence that PCB118 may induce thyroidal autophagy through TUBB3-related signaling pathway, and these effects are likely to be regulated by calcium influx via SOCE channel.

Effects of protein kinase C activators on the in-vitro action of thyrotrophin in pigs

1988 ◽  
Vol 118 (2) ◽  
pp. 199-203 ◽  
Author(s):  
J. Ginsberg ◽  
P. G. Murray
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Thyroid Function ◽  
Receptor Site ◽  
Thyroid Cell ◽  
Thyroid Cells ◽  
Cell Extracts ◽  
Kinase C

ABSTRACT The ability of the non-phorbol protein kinase C (PKC) activator 12-hydroxy-daphnetoxin (mezerein) to modulate differentiated thyroid function was examined in vitro. A dose-dependent inhibition of TSH-stimulated iodide organification was observed in porcine thyroid cells exposed to mezerein. Under identical conditions mezerein caused the translocation of PKC from its inactive cytosolic form to an active membrane-bound form in thyroid cell extracts. The relative biological potencies of mezerein and the phorbol ester, 12-0-tetradecanoylphorbol-13-acetate (TPA), to inhibit thyroid function in vitro corresponded to their abilities to activate PKC. This effect was also observed when dibutyryl cyclic AMP was used, implying a post-receptor site of action. To provide further evidence for this concept, the effects of mezerein and TPA on receptor-related events were studied. Neither mezerein nor TPA had any effect on the binding of radiolabelled TSH to solubilized porcine thyroid membranes. However, both mezerein and TPA were capable of stimulating cyclic AMP (cAMP) production in porcine thyroid cells in the basal state but could not augment TSH or forskolin-activated cAMP release. These data provide evidence that activation of PKC plays a role in the regulation of differentiated thyroid function in vitro and suggest that the effects of PKC are complex, with independent actions on cAMP accumulation and post-receptor events. J. Endocr. (1988) 118, 199–203

scholarly journals The new generation PFAS C6O4 does not produce adverse effects on thyroid cells in vitro

2020 ◽  
Author(s):  
F. Coperchini ◽  
L. Croce ◽  
P. Pignatti ◽  
G. Ricci ◽  
D. Gangemi ◽  
...  
Keyword(s):  
Adverse Effects ◽  
Cell Viability ◽  
Human Thyroid ◽  
Thyroid Cell ◽  
Ros Production ◽  
Thyroid Cells ◽  
Time Points ◽  
Rat Thyroid ◽  
Long Chain

Abstract Purpose Per- and poly-fluoroalkyl-substances (PFASs) are synthetic compounds that raised concern due to their potential adverse effects on human health. Long-chain PFAS were banned by government rules in many states, and thus, new emerging PFAS were recently introduced as substitutes. Among these, Perfluoro{acetic acid, 2-[(5-methoxy-1,3-dioxolan-4-yl)oxy]}, ammonium salt (C6O4) was recently introduced to produce a range of food contact articles and literature data about this compound are scanty. The aim of this study was to evaluate the in vitro effects of exposure to C6O4, compared with PFOA and PFOS on thyroid cells. Methods FRTL5 rat-thyroid cell lines and normal human thyroid cells (NHT) were incubated with increasing concentrations of C6O4 for 24, 48, 72, and 144 h to assess cell viability by WST-1. Cell viability was confirmed by AnnexinV/PI staining. Long-chain PFAS (PFOA and PFOS) were used at same concentrations as positive controls. The proliferation of cells exposed to C6O4, PFOA, and PFOS was measured by staining with crystal violet and evaluation of optical density after incubation with SDS. Changes in ROS production by FRTL5 and NHT after exposure to C6O4 at short (10, 20, and 30 min) and long-time points (24 h) were evaluated by cytofluorimetry. Results C6O4 exposure did not modify FRTL5 and NHT cell viability at any concentration and/or time points with no induction of necrosis/apoptosis. At difference, PFOS exposure reduced cell viability of FRTL5 while and NHT, while PFOA only in FRTL5. FRTL5 and NHT cell proliferation was reduced by incubation with by PFOA and PFOS, but not with C6O4. ROS production by NHT and FRTL5 cells was not modified after C6O4 exposure, at any time/concentration tested. Conclusions The present in vitro study constitutes the first evaluation of the potential adverse effects of the new emerging PFAS C6O4 in cultured rat and human thyroid cells, suggesting its safety for thyroid cells in vitro.

Control of thyroglobulin secretion from the rat thyroid gland

1984 ◽  
Vol 101 (1) ◽  
pp. 107-111 ◽  
Author(s):  
E. G. Black ◽  
M. C. Sheppard ◽  
R. Hoffenberg
Keyword(s):  
Thyroid Stimulating Hormone ◽  
Dependent Manner ◽  
Serum Thyroglobulin ◽  
Thyroid Cells ◽  
Normal Rat ◽  
Rat Thyroid ◽  
Dose Dependent ◽  
Rat Thyroid Gland

ABSTRACT Serum thyroglobulin (Tg), measured by radioimmunoassay, was high in 6-propylthiouracil (PTU)-treated rats but low in thyroxine (T4)-treated animals compared with euthyroid controls. Thyroid-stimulating hormone (TSH) stimulated Tg release in vitro from enzymatically dispersed normal rat thyroid cells in a dose-dependent manner. Thyroid cells prepared from T4-treated animals behaved similarly to cells from control rats, whereas in vitro basal release of Tg from thyroid cells prepared from PTU-treated animals was high and the response to TSH was lost. Our data confirm the TSH dependency of Tg release in vivo and in vitro and our system provides a means of studying the control of Tg secretion in vitro. J. Endocr. (1984) 101, 107–111

Sign in / Sign up

Export Citation Format

Share Document