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Nakazawa D, Nishio S, Tomaru U, Atsumi T, Ishizu A. [NETs in pathogenesis of vasculitis]. NIHON JINZO GAKKAI SHI 2014; 56:117-123. [PMID: 24730349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
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Gorodetskaia IV, Gusakova EA. [Effect of thyroid status on the system proteolysis under stress]. ROSSIISKII FIZIOLOGICHESKII ZHURNAL IMENI I.M. SECHENOVA 2013; 99:1378-1388. [PMID: 25464768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Introduction of merkazolil to in rats (25 mg/kg 20 days), causing reduction of iodine containing thyroid hormones levels (ITH) in the blood, reduces the trypsin-like activity (TLA) and the activity of α1-antitrypsin (α1-AT) and α2-macroglobulin (α2-MG) in the liver and blood; in the alarm-stage of stress reaction (1 hour after swimming in a cage) it defines more pronounced than that in euthyroid animals stimulation of proteolysis due to the decline of α1-AT and α2-MG activity, in stage of resistance (48 hours) it prevents the normalization of TLA, α1-AT and α2-MG activity, which took place in the stress at the euthyrosis; in the stage of exhaustion (1 hour of the stress within 10 days) promotes to the most significant activation of the proteolysis owing to profound inhibition of the α1-AT and α2-MG. The introduction of L-thyroxine (1.5-3.0 μg/kg 28 days) does not change the concentration of ITH in the blood and it does not affect the proteolyis system; in the alarm- and exhaustion stages it limits the increase of the TLA, in the stage of re-istance prevents it, eliminating the depression of aα1AT and aα-MG activity. The results demon-trate a new aspect of the participation of ITH in the body anti-stress system --heir effect on pro-ease/inhibitor system.
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Gorodetskaia IV, Evdokimova OV. [The dependence of lipid peroxidation state and the antioxidant system of the myocardium from the thyroid status during short action of stressors]. ROSSIISKII FIZIOLOGICHESKII ZHURNAL IMENI I.M. SECHENOVA 2013; 99:1285-1293. [PMID: 25427382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In experiments at 78 adult white outbred male rats were demonstrated that experimental hypothyroidism (injection of 25 mg/kg merkazolil within 20 days) stimulates, while small doses of L-thyroxine (1.5-3.0 μg/kg within 28 days) limit the intensification of lipid peroxidation in the myocardium under short exposure to stressors of a different nature: physical (t 4-5 °C within 30 minutes), chemical (injection of 25% ethanol at a dose of 3.5 g/kg body weight), and emotional (free swimming of rats in the cage within 30 minutes) by influence on the activity of enzymatic (superoxide dismutase and catalase) and non-enzymatic (reduced glutathione) components of the antioxidant system.
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Gusakova EA, Gorodetskaia IV. [Iodine-containing thyroid hormones increases the motor activity of rats under stress]. ROSSIISKII FIZIOLOGICHESKII ZHURNAL IMENI I.M. SECHENOVA 2013; 99:1300-1312. [PMID: 25427384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
It is established that alarm-stage of stress reaction (1 hour after the swimming of rats in a cage within 1 hour) is characterized by a decrease of total vertical motor activity (MA) and by the chan- ge of behavior structure--disappearance of racks without support on the board of "open field" and a central horizontal part of MA as well as an increase in physical endurance of rats; stage of resistan- ce (48 hours after the stress)--the restoration of motor reactions of animals, and stage of exhaustion (1 hour within 10 days of stress)--its oppression. Introduction of merkazolil (25 mg/kg, 20 da- ys) causes a fall of level of iodine-containing thyroid hormones (ITH) in the blood and causes a significant reduction of all types of MA and change of the structure of behavior in the alarm-stage, practically eliminating its normalization in stage of resistance and provokes its greatest violation in a stage of exhaustion of stress reaction. Introduction of L-thyroxine (1.5-3.0 μg/kg 28 days) does not change the ITH concentration in the blood, increases MA of rats, and provides its higher level and maintaining of the structure of behavior in all stages of stress reaction.
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Abstract
Changes in thyroid hormone concentrations that are characteristic of hyperthyroidism must be distinguished from physiological changes in thyroid hormone economy that occur in pregnancy, especially in the first trimester. Approximately one to two cases of gestational hyperthyroidism occur per 1000 pregnancies. Identification of hyperthyroidism in a pregnant woman is important because adverse outcomes can occur in both the mother and the offspring. Graves' disease, which is autoimmune in nature, is the usual cause; but hyperthyroidism in pregnancy can be caused by any type of hyperthyroidism--eg, toxic multinodular goitre or solitary autonomously functioning nodule. Gestational transient thyrotoxicosis is typically reported in women with hyperemesis gravidarum, and is mediated by high circulating concentrations of human chorionic gonadotropin. Post-partum thyroiditis occurs in 5-10% of women, and many of those affected ultimately develop permanent hypothyroidism. Antithyroid drug treatment of hyperthyroidism in pregnant women is controversial because the usual drugs--methimazole or carbimazole--are occasionally teratogenic; and the alternative--propylthiouracil--can be hepatotoxic. Fetal hyperthyroidism can be life-threatening, and needs to be recognised as soon as possible so that treatment of the fetus with antithyroid drugs via the mother can be initiated. In this Review, we discuss physiological and pathophysiological changes in thyroid hormone economy in pregnancy, the diagnosis and management of hyperthyroidism during pregnancy, severe life-threatening thyrotoxicosis in pregnancy, neonatal thyrotoxicosis, and post-partum hyperthyroidism.
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Pathak S, Kundu R. Effects of low concentrations of a polychlorinated biphenyl, Aroclor 1254 on membrane bound ion dependent ATPases in mice liver. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 2013; 51:477-480. [PMID: 23926697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Aroclor 1254, a polychlorinated biphenyl, is present in the environment in low concentration but references on its toxic effects on liver cell membrane proteins and the mechanism of actions are not abundantly available. Therefore, the present study was undertaken to investigate the low level, sub-acute dose and exposure duration dependent effects of Aroclor 1254 on total, Na+, K+, Ca2+ and Mg(2+)-ATPases of the mouse liver. The hypotheses tested in the present study were, (a) whether the low, environmentally available dose and the exposure durations of Aroclor 1254 affects the membrane-bound ion dependent ATPases, and (b) if a response was observed, whether it is a direct or indirect effects of the toxicant. Groups of mice were exposed to different doses (0.1 and 1 mg kg(-1) body weight d(-1)) and exposure durations (4 d, 8 d and 12 d) of Aroclor 1254. The results indicated significant exposure duration dependent changes in the specific activity of the selected membrane bound ATPases. As the observed changes were mostly enzyme stimulation after toxication through oral administration, the effects of the Aroclor were possibly indirect, through complex chain of reactions.
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Sharma P, Patiño R. Regulation of gonadal sex ratios and pubertal development by the thyroid endocrine system in zebrafish (Danio rerio). Gen Comp Endocrinol 2013; 184:111-9. [PMID: 23337033 DOI: 10.1016/j.ygcen.2012.12.018] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2012] [Revised: 11/12/2012] [Accepted: 12/25/2012] [Indexed: 11/27/2022]
Abstract
We examined associations between thyroid condition, gonadal sex and pubertal development in zebrafish. Seventy-two-hour postfertilization larvae were reared in untreated medium or in the presence of goitrogens (sodium perchlorate, 0.82 mM; methimazole, 0.15 and 0.3 mM) or thyroxine (1 and 10 nM) for 30 days. Thyrocyte height, gonadal sex and gonadal development were histologically determined at 45 and 60 days postfertilization (dpf). Thyrocyte hypertrophy, an index of hypothyroidism, was observed at 45 and 60 dpf in perchlorate-treated but only at 45 dpf in methimazole-treated fish. Similarly, gonadal sex ratios were biased toward ovaries relative to control animals at 45 and 60 dpf in perchlorate-treated fish but only at 45 dpf in methimazole-treated fish. Gonadal sex ratios were biased toward testes at 45 and 60 dpf in thyroxine-treated fish. Spermatogenesis was delayed in testes from goitrogen-treated fish at 60 dpf relative to control values, but was unaffected in testes from thyroxine-treated individuals. Oogenesis seemed to be nonspecifically delayed in all treatments relative to control at 60 dpf. This study confirmed the previously reported association between hypothyroid condition and ovarian-skewed ratios, and hyperthyroid condition and testicular-skewed ratios, and also showed that male pubertal development is specifically delayed by experimental hypothyroidism. The simultaneous recovery from the hypothyroid and ovary-inducing effects of methimazole by 60 dpf (27 days post-treatment) suggests that the ovary-skewing effect of goitrogens is reversible when thyroid conditions return to basal levels before developmental commitment of gonadal sex. Conversely, the masculinizing effect of hyperthyroidism seems to be stable and perhaps permanent.
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Escudero GE, Ferraresi Curotto V, Laino CH, Pis Diez R, Williams PAM, Ferrer EG. Sertraline and its iodine product: experimental and theoretical vibrational studies: potential in vitro anti-thyroid activity of sertraline and iodine product toxicity with respect to male Wistar rats. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 104:271-279. [PMID: 23270885 DOI: 10.1016/j.saa.2012.11.076] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Revised: 11/15/2012] [Accepted: 11/23/2012] [Indexed: 06/01/2023]
Abstract
Mayor depression, obsessive-compulsive panic, social anxiety disorders are common diseases that are usually treated with sertraline hydrochloride which is the active ingredient of the well known drugs as Zoloft and Lustral. In this work, we presented a more complete vibrational characterization of the solid phase FT-IR spectra of Sertraline hydrochloride and its sertraline-iodine product in which the conformational space of the molecules was investigated performing molecular dynamic simulations within an NVT ensemble. Geometrical, electronic and vibrational properties were calculated with the density functional theory. Comparison of the simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes of both molecules. In addition, for the first time we present the evaluation of anti-thyroid activity of sertraline hydrochloride by using the Lang's method. Also, with the aim to evaluate the antidepressant effect of its iodine product we demonstrated for this compound the toxic effect towards the male Wistar rats.
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Bohnsack BL, Kahana A. Thyroid hormone and retinoic acid interact to regulate zebrafish craniofacial neural crest development. Dev Biol 2013; 373:300-9. [PMID: 23165295 PMCID: PMC3534885 DOI: 10.1016/j.ydbio.2012.11.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 11/07/2012] [Accepted: 11/08/2012] [Indexed: 01/17/2023]
Abstract
Craniofacial and ocular morphogenesis require proper regulation of cranial neural crest migration, proliferation, survival and differentiation. Although alterations in maternal thyroid hormone (TH) are associated with congenital craniofacial anomalies, the role of TH on the neural crest has not been previously described. Using zebrafish, we demonstrate that pharmacologic and genetic alterations in TH signaling disrupt cranial neural crest migration, proliferation, and survival, leading to craniofacial, extraocular muscle, and ocular developmental abnormalities. In the rostral cranial neural crest that gives rise to the periocular mesenchyme and the frontonasal process, retinoic acid (RA) rescued migratory defects induced by decreased TH signaling. In the caudal cranial neural crest, TH and RA had reciprocal effects on anterior and posterior pharyngeal arch development. The interactions between TH and RA signaling were partially mediated by the retinoid X receptor. We conclude that TH regulates both rostral and caudal cranial neural crest. Further, coordinated interactions of TH and RA are required for proper craniofacial and ocular development.
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Fukuiri T, Takumida M, Nakashimo Y, Hirakawa K. Expression of prostanoid receptors (EP1, 2, 3, and 4) in normal and methimazole-treated mouse olfactory epithelium. Acta Otolaryngol 2013; 133:70-6. [PMID: 22991925 DOI: 10.3109/00016489.2012.712214] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CONCLUSION Prostanoid receptors (EP1, EP2, EP3, and EP4) are expressed in the olfactory epithelium (OE), and the EP4 prostanoid receptor may play an important role in the OE. OBJECTIVE The purpose of the present study was to investigate the expression and localization of the four types of prostanoid receptors (EP1, EP2, EP3, and EP4) in the OE of normal and methimazole-treated mice to gain more complete knowledge about the functional significance of the prostanoid receptors in OE. METHODS CBA/J mice were used in this study. The localization of the prostanoid receptors (EP1, EP2, EP3, and EP4) in the OE was investigated by immunohistochemistry. The changes in expression of prostanoid receptors were studied in methimazole-treated mice. Furthermore, the effect of EP agonists on the methimazole-induced degeneration of OE was assessed by morphological analysis and by assessment of apoptosis. RESULTS All four types of EP receptors were recognized in mouse OE. Expression of EP4 in the OE was significantly reduced after methimazole treatment. In the methimazole-treated mice, an EP4 agonist reduced OE damage and apoptosis.
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Abstract
The physiological role of the TSH receptor (TSHR) as a major regulator of thyroid function is well understood, but TSHRs are also expressed in multiple normal extrathyroidal tissues, and the physiological roles of TSHRs in these tissues are unclear. Moreover, TSHRs play a major role in several pathological conditions including hyperthyroidism, hypothyroidism, and thyroid tumors. Small molecule, "drug-like" TSHR agonists, neutral antagonists, and inverse agonists may be useful as probes of TSHR function in extrathyroidal tissues and as leads to develop drugs for several diseases of the thyroid. In this Update, we review the most recent findings regarding the development and use of these small molecule TSHR ligands.
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Jahan S, Ahmed S, Emanuel E, Fatima I, Ahmed H. Effect of an anti-thyroid drug, 2,8-Dimercapto-6-hydroxy purine on reproduction in male rats. PAKISTAN JOURNAL OF PHARMACEUTICAL SCIENCES 2012; 25:401-406. [PMID: 22459469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
This histomorphological study is designed to evaluate the peripheral action of 2,8-Dimercapto-6-hydroxypurine (an antithyroid drug) on male reproductive system. The drug was administered as i.p. injection for 21 days to investigate its role on morphology of intratesticular cells and plasma testosterone level. Adult male rats (n=12), divided into three groups i.e. control, dimethylsulphoxide (DMSO) and 2,8-Dimercapto-6-hydroxypurine treated groups and treated with saline, DMSO and 2,8-Dimercapto-6-hydroxypurine for 21 consecutive days respectively. Blood samples were collected at day 1, 7, 14 and 21 and analyzed by using EIA systems. All the animals were scarified on 22nd day and testicular tissues were studied by histomorphpological assesment. 2,8-Dimercapto-6-hydroxypurine caused a significant decrease (P<0.0001) in mean testicular cell population, testicular cell diameter and resulted in arrested spermatogenesis. A significant decrease (P<0.0001) was observed in mean Sertoli and Leydig cell population and diameter in treated group. Similarly a significant decrease was observed in plasma testosterone levels at days 1, 7 and 14 (P<0.05) and further decrease by day 21 (P<0.01) of drug treatment. The present study suggests that 2,8-Dimercapto-6-hydroxypurine is a negative modulator of reproductive system as it suppressed the plasma testosterone level and proliferation of different testicular cell types in adult male rats.
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Abstract
Thyrotoxicosis is a common disorder, especially in women. The most frequent cause is Graves' disease (autoimmune hyperthyroidism). Other important causes include toxic nodular hyperthyroidism, due to the presence of one or more autonomously functioning thyroid nodules, and thyroiditis caused by inflammation, which results in release of stored hormones. Antithyroid drugs are the usual initial treatment (thionamides such as carbimazole or its active metabolite methimazole are the drugs of choice). A prolonged course leads to remission of Graves' hyperthyroidism in about a third of cases. Because of the low remission rate in Graves' disease and the inability to cure toxic nodular hyperthyroidism with antithyroid drugs alone, radioiodine is increasingly used as first line therapy, and is the preferred choice for relapsed Graves' hyperthyroidism. Total thyroidectomy is an option in selected cases. Future efforts are likely to concentrate on novel and safe ways to modulate the underlying disease process rather than stopping excess thyroid hormone production.
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Calil-Silveira J, Serrano-Nascimento C, Nunes MT. Iodide treatment acutely increases pendrin (SLC26A4) mRNA expression in the rat thyroid and the PCCl3 thyroid cell line by transcriptional mechanisms. Mol Cell Endocrinol 2012; 350:118-24. [PMID: 22178794 DOI: 10.1016/j.mce.2011.12.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Revised: 12/01/2011] [Accepted: 12/01/2011] [Indexed: 10/14/2022]
Abstract
Iodine is a critical element involved in thyroid hormone synthesis. Its efflux into the follicular lumen is thought to occur, in part, through pendrin at the apical membrane of thyrocytes. This study attempted to investigate whether iodide administration affects SLC26A4 mRNA expression in rat thyroid and in PCCl3 cells. Rats and cells were treated or not with NaI from 30 min up to 48 h. One group was concomitantly treated with sodium perchlorate. SLC26A4 mRNA expression was also investigated in PCCl3 cells treated with actinomycin D prior to NaI treatment. Iodide administration significantly increased SLC26A4 mRNA content in both models. The simultaneous administration of NaI and perchlorate, as well as the treatment of PCCl3 cells with actinomycin D prevented this effect, indicating that intracellular iodide is essential for this event, which appears to be triggered by transcriptional mechanisms. These data show that intracellular iodide rapidly upregulates SLC26A4 mRNA expression.
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Serrano-Nascimento C, Calil-Silveira J, Goulart-Silva F, Nunes MT. New insights about the posttranscriptional mechanisms triggered by iodide excess on sodium/iodide symporter (NIS) expression in PCCl3 cells. Mol Cell Endocrinol 2012; 349:154-61. [PMID: 22001309 DOI: 10.1016/j.mce.2011.09.036] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 09/06/2011] [Accepted: 09/24/2011] [Indexed: 10/17/2022]
Abstract
Iodide excess acutely downregulates NIS mRNA expression, as already demonstrated. PCCl3 cells treated or not with NaI, NaI+NaClO(4) or NaI+Methimazole, for 30 min to 24 h, were used to further explore how iodide reduces NIS gene expression. NIS mRNA expression was evaluated by Real-Time PCR; its poly(A) tail length, by RACE-PAT; its translation rate, by polysome profile; total NIS content, by Western blotting. NIS mRNA decay rate was evaluated in actinomycin-D-treated cells, incubated with or without NaI for 0-6 h. Iodide treatment caused a reduction in NIS mRNA expression, half-life, poly(A) tail length, recruitment to ribosomes, as well as NIS protein expression. Perchlorate, but not methimazole, prevented these effects. Therefore, reduced poly(A) tail length of NIS mRNA seems to be related to its decreased half-life, in addition to its translation impairment. These data provide new insights about the molecular mechanisms involved in the rapid and posttranscriptional inhibitory effect of iodide on NIS expression.
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Tagami T, Yambe Y, Tanaka T, Tanaka T, Ogo A, Yoshizumi H, Kaise K, Higashi K, Tanabe M, Shimazu S, Usui T, Shimatsu A, Naruse M. Short-term effects of β-adrenergic antagonists and methimazole in new-onset thyrotoxicosis caused by Graves' disease. Intern Med 2012; 51:2285-90. [PMID: 22975536 DOI: 10.2169/internalmedicine.51.7302] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
OBJECTIVE β-adrenergic antagonists (β-blockers) are often used to attenuate the hyperadrenergic symptoms of Graves' disease (GD), including palpitation. Although β-blockers reduce the heart rate, cardiac output and oxygen consumption, no firm evidence exists regarding the effects of combined therapy with β-blockers and anti-thyroid drugs. The objective is to elucidate the effects of β-blockers on anti-thyroid drug therapy in GD. METHODS Patients newly diagnosed with mild GD were randomly assigned to receive methimazole with or without β-blockers in a prospective multi-center survey. The heart rate and thyroid function were measured and the quality of life was assessed using original and SF-36 questionnaires at 0 and 4 weeks. RESULTS A total of 28 patients were enrolled in the study. Fourteen patients (one man, 13 women) were randomly assigned to the group treated with β-blockers and 14 patients (one man, 13 women) were randomly assigned to the group not treated with β-blockers. Although no significant differences in the improvement of thyroid function were observed between the two groups, the heart rates improved more significantly in the group treated with β-blockers. Specific symptoms, such as easy fatigability and shortness of breath, also improved more significantly with the β-blocker treatment. In addition, 'physical functioning' assessed with the SF-36 questionnaires significantly improved only in the group treated with β-blockers. CONCLUSION Although β-blockers may not reinforce the effects of anti-thyroid drugs on thyroid function, at least during the course of one month, they are effective in reducing heart rates and ameliorating specific symptoms in patients with mild GD.
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Alva-Sánchez C, Pacheco-Rosado J, Fregoso-Aguilar T, Villanueva I. The long-term regulation of food intake and body weight depends on the availability of thyroid hormones in the brain. NEURO ENDOCRINOLOGY LETTERS 2012; 33:703-708. [PMID: 23391881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 11/04/2012] [Indexed: 06/01/2023]
Abstract
OBJECTIVES We evaluated the contribution of the thyroid hormones to the long-term maintenance of feeding behavior and body weight, while distinguishing their direct central effects from those resulting from the metabolic rate in the peripheral tissues. METHODS We assessed the effect of hypothyroidism on the long-term (6 months) regulation of food intake, body weight, and energy expenditure in rats. We then generated the recovery of a euthyroid condition in the brain while maintaining a low T3 availability for the peripheral organs, i.e. a combined condition of central euthyroidism with peripheral hypothyroidism, with the aid of a pharmacological combination. RESULTS Hypothyroidism caused a decrease in the daily food intake, body weight, and body temperature. The food intake and body temperature stabilized at a lower value, whereas body weight kept decreasing at a constant rate. The administration of exogenous T4 increased food intake and body-weight gain, but had no effect on body temperature. CONCLUSIONS The thyroid hormones are necessary for the long-term regulation of energy intake, storage, and expenditure by different mechanisms. The feeding behavior seems to be partially dependent on a direct action of the thyroid hormones on the brain and this effect is independent of the energy expenditure in the peripheral organs. The body weight is closely dependent on the thyroid status and its maintenance seems to involve thyroid action on mechanisms other than feeding and metabolic rate.
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Léger J, Gelwane G, Kaguelidou F, Benmerad M, Alberti C. Positive impact of long-term antithyroid drug treatment on the outcome of children with Graves' disease: national long-term cohort study. J Clin Endocrinol Metab 2012; 97:110-9. [PMID: 22031519 DOI: 10.1210/jc.2011-1944] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Drug-based therapy is usually the initial treatment for Graves' disease (GD) hyperthyroidism in children, but there is some debate about treatment duration. OBJECTIVE Our objective was to assess the effect of long-term carbimazole therapy on GD remission in children and its determinants. DESIGN AND SETTING This was an observational prospective multicenter follow-up cohort study. PARTICIPANTS Participants included 154 children newly diagnosed with GD between 1997 and 2002. The intention was to treat patients with three consecutive courses of carbimazole, each lasting 2 yr. Definitive treatment was performed in cases of poor compliance with antithyroid drug (ATD) treatment, thyrotoxicosis relapse, or major adverse effects of ATD treatment. MAIN OUTCOME MEASURE The main outcome measure was remission for at least 18 months after the completion of each course of ATD treatment. RESULTS The median duration of follow-up was 10.4 (9.0-12.1) yr. Overall estimated remission rates (95% confidence interval) 18 months after the withdrawal of ATD treatment increased with time and were 20 (13-26), 37 (29-45), 45 (35-54), and 49 (40-57)% after 4, 6, 8, and 10 yr follow-up, respectively. A multivariate competing risk model revealed an independent positive effect of less severe forms of hyperthyroidism at diagnosis [subhazard ratio of 1 for patients with free T(4) <35 pmol/liter vs. 0.4 (0.20-0.80) for free T(4) ≥ 35 pmol/liter; P = 0.01] and of the presence of other autoimmune conditions [subhazard ratio of 2.23 (1.19-4.18); P = 0.01] on remission rate after medical treatment. CONCLUSION About half the patients achieved remission after carbimazole discontinuation, and there seems to be a plateau in the incidence of remission achieved after 8-10 yr ATD therapy.
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Gorodetskaia IV, Korenevskaia NA. [Dependence of organism stability on chronic stress from thyroid status]. ROSSIISKII FIZIOLOGICHESKII ZHURNAL IMENI I.M. SECHENOVA 2011; 97:1346-1354. [PMID: 22384675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In experiences on 108 male rats, the effect of acute (immobilization during 3 hrs) and chronic (immobilization for 3 hrs during 5 days) stresses on the organism general stability was studied as evaluated with changes of body weight, adrenal glands, spleen, thymus relative mass, gastric mucosa state, animals physical endurance. Chronic stress evoked more obvious decreasing of spleen and thymus relative mass than the acute one, as well as lesion of gastric mucosa accompanied with decrease of the rat resistance to physical loading. Thyroid function suppression by merkazolil (1.2 mg/100 g body weight during 14 days) promotes further the reduction of the organism stability in acute and, especially, in chronic stress, while physiological doses of thyroid hormones (5.0-8.0 mcg of thyroxin on kg of body weight during 28 days), on the contrary, increased it in both stress conditions. Existence of the organism stability dependence on thyroid status both in acute and chronic stress proves iodothyronine's important role in the organism antistress-system.
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Carvalho ESM, Fuentes J, Power DM. Integument structure and function in juvenile Xenopus laevis with disrupted thyroid balance. Gen Comp Endocrinol 2011; 174:301-8. [PMID: 21963960 DOI: 10.1016/j.ygcen.2011.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2011] [Revised: 08/31/2011] [Accepted: 09/09/2011] [Indexed: 10/17/2022]
Abstract
The skin is the largest organ in the body and is a barrier between the internal and external environment. The present study evaluates how PTU, a goitrogen, that is used to treat hyperthyroidism affects the structure and electrical properties of the frog (Xenopus laevis) skin. The results are considered in the context of the two-membrane model established in the seminal work of Ussing and collegues in the 1940s and 1950s. In vitro experiments with skin from Xenopus adults revealed that PTU can act directly on skin and causes a significant increase (p<0.05, One-way ANOVA) in short circuit current (Isc) via an amiloride-insensitive mechanism. Juvenile Xenopus exposed to waterborne PTU (5 mg/L) had a significantly bigger and more active thyroid gland (p<0.01, Student's t-test) than control Xenopus. The bioelectric properties of skin taken from Xenopus juveniles treated with PTU in vivo had a lower Isc, (3.05±0.4, n=13) and Rt (288.2±39.5) than skin from control Xenopus (Isc, 4.19±1.14, n=14; Rt, 343.3±43.3). A histological assessment of skin from PTU treated Xenopus juveniles revealed the epidermis was significantly thicker (p<0.01, Student's t-test) and had a greater number of modified exocrine glands (p<0.01, Student's t-test) in the dermis compared to control skin. Modifications in skin structure are presumably the basis for its changed bioelectric properties and the study highlights a site of action for environmental chemicals which has been largely neglected.
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71
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Thienpont B, Tingaud-Sequeira A, Prats E, Barata C, Babin PJ, Raldúa D. Zebrafish eleutheroembryos provide a suitable vertebrate model for screening chemicals that impair thyroid hormone synthesis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:7525-7532. [PMID: 21800831 DOI: 10.1021/es202248h] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Thyroxine-immunofluorescence quantitative disruption test (TIQDT) was designed to provide a simple, rapid, alternative bioassay for assessing the potential of chemical pollutants and drugs to disrupt thyroid gland function. This study demonstrated that zebrafish eleutheroembryos provided a suitable vertebrate model, not only for screening the potential thyroid disrupting effect of molecules, but also for estimating the potential hazards associated with exposure to chemicals directly impairing thyroxine (T4) synthesis. Amitrole, potassium perchlorate, potassium thiocyanate, methimazole (MMI), phloroglucinol, 6-propyl-2-thiouracil, ethylenethiourea, benzophenone-2, resorcinol, pyrazole, sulfamethoxazole, sodium bromide, mancozeb, and genistein were classified as thyroid gland function disruptors. Concordance between TIQDT on zebrafish and mammalian published data was very high and the physiological relevance of T4-intrafollicular content was clearly higher than regulation at the transcriptional level of tg or slc5a5. Moreover, concentration-response analysis provided information about the thyroid disrupting potency and hazard of selected positive compounds. Finally, the effect of perchlorate, but not MMI, was completely rescued by low-micromolar amounts of iodide. TIQDT performed on zebrafish eleutheroembryos is an alternative whole-organism screening assay that provides relevant information for environmental and human risk assessments.
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72
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Bolotovskii AA, Levin BA. [Influence of development pace on pharyngeal teeth formula in Abramis brama (L.) bream: experimental data]. ONTOGENEZ 2011; 42:172-177. [PMID: 21786649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
An experiment on acceleration and retardation of ontogenesis with thyroid manipulation has revealed direct changes in definitive dentition of pharyngeal bones in Abramis brama bream. As development pace accelerates, the number of teeth reduces to the formula 5-4. When development pace slows down, this number increases to the formula 6-5. Moreover, an additional minor row of teeth (1.6-5.1, 2.6-5.2) is formed. The observed changes transcend typical changes happening in nature. It is assumed that heterochronies provoke changes in the number of teeth.
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73
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Marsili A, Ramadan W, Harney JW, Mulcahey M, Castroneves LA, Goemann IM, Wajner SM, Huang SA, Zavacki AM, Maia AL, Dentice M, Salvatore D, Silva JE, Larsen PR. Type 2 iodothyronine deiodinase levels are higher in slow-twitch than fast-twitch mouse skeletal muscle and are increased in hypothyroidism. Endocrinology 2010; 151:5952-60. [PMID: 20881246 PMCID: PMC2999482 DOI: 10.1210/en.2010-0631] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Accepted: 08/30/2010] [Indexed: 12/28/2022]
Abstract
Because of its large mass, relatively high metabolic activity and responsiveness to thyroid hormone, skeletal muscle contributes significantly to energy expenditure. Despite the presence of mRNA encoding the type 2 iodothyronine-deiodinase (D2), an enzyme that activates T(4) to T3, very low or undetectable activity has been reported in muscle homogenates of adult humans and mice. With a modified D2 assay, using microsomal protein, overnight incubation and protein from D2 knockout mouse muscle as a tissue-specific blank, we examined slow- and fast-twitch mouse skeletal muscles for D2 activity and its response to physiological stimuli. D2 activity was detectable in all hind limb muscles of 8- to 12-wk old C57/BL6 mice. Interestingly, it was higher in the slow-twitch soleus than in fast-twitch muscles (0.40 ± 0.06 vs. 0.076 ± 0.01 fmol/min · mg microsomal protein, respectively, P < 0.001). These levels are greater than those previously reported. Hypothyroidism caused a 40% (P < 0.01) and 300% (P < 0.001) increase in D2 activity after 4 and 8 wk treatment with antithyroid drugs, respectively, with no changes in D2 mRNA. Neither D2 mRNA nor activity increased after an overnight 4 C exposure despite a 10-fold increase in D2 activity in brown adipose tissue in the same mice. The magnitude of the activity, the fiber specificity, and the robust posttranslational response to hypothyroidism argue for a more important role for D2-generated T(3) in skeletal muscle physiology than previously assumed.
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74
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Schreiber AM, Wang X, Tan Y, Sievers Q, Sievers B, Lee M, Burrall K. Thyroid hormone mediates otolith growth and development during flatfish metamorphosis. Gen Comp Endocrinol 2010; 169:130-7. [PMID: 20736011 DOI: 10.1016/j.ygcen.2010.08.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2010] [Revised: 08/03/2010] [Accepted: 08/16/2010] [Indexed: 11/15/2022]
Abstract
Flatfish begin life as bilaterally symmetrical larvae that swim up-right, then abruptly metamorphose into asymmetrically shaped juveniles with lateralized swimming postures. Flatfish metamorphosis is mediated entirely by thyroid hormone (TH). Changes in flatfish swim posture are thought to be regulated via vestibular remodeling, although the influence of TH on teleost inner ear development remains unclear. This study addresses the role of TH on the development of the three otolith end-organs (sacculus, utricle, and lagena) during southern flounder (Paralichthys lethostigma) metamorphosis. Compared with pre-metamorphosis, growth rates of the sacculus and utricle otoliths increase dramatically during metamorphosis in a manner that is uncoupled from general somatic growth. Treatment of P. lethostigma larvae with methimazol (a pharmacological inhibitor of endogenous TH production) inhibits growth of the sacculus and utricle, whereas treatment with TH dramatically accelerates their growth. In contrast with the sacculus and utricle otoliths that begin to form and mineralize during embryogenesis, a non-mineralized lagena otolith is first visible 10-12 days after hatching. The lagena grows during pre- and pro-metamorphosis, then abruptly mineralizes during metamorphic climax. Mineralization of the lagena, but not growth, can be induced with TH treatment, whereas treatment with methimazol completely inhibits lagena mineralization without inhibiting its growth. These findings suggest that during southern flounder metamorphosis TH exerts differential effects on growth and development among the three types of otolith.
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75
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Wang YY, Morimoto S, Du CK, Lu QW, Zhan DY, Tsutsumi T, Ide T, Miwa Y, Takahashi-Yanaga F, Sasaguri T. Up-regulation of type 2 iodothyronine deiodinase in dilated cardiomyopathy. Cardiovasc Res 2010; 87:636-46. [PMID: 20453157 DOI: 10.1093/cvr/cvq133] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
AIMS Thyroid hormone (TH) has prominent effects on the heart, and hyperthyroidism is occasionally found to be a cause of dilated cardiomyopathy (DCM). We aim to explore the potential role of TH in the pathogenesis of DCM. METHODS AND RESULTS The pathophysiological role of TH in the heart was investigated using a knock-in mouse model of inherited DCM with a deletion mutation DeltaK210 in the cardiac troponin T gene. Serum tri-iodothyronine (T(3)) levels showed no significant difference between wild-type (WT) and DCM mice, whereas cardiac T(3) levels in DCM mice were significantly higher than those in WT mice. Type 2 iodothyronine deiodinase (Dio2), which produces T(3) from thyroxin, was up-regulated in the DCM mice hearts. The cAMP levels were increased in DCM mice hearts, suggesting that transcriptional up-regulation of Dio2 gene is mediated through the evolutionarily conserved cAMP-response element site in its promoter. Propylthiouracil (PTU), an anti-thyroid drug, prevented the hypertrophic remodelling of the heart in DCM mice and improved their cardiac function and life expectancy. Akt and p38 mitogen-activated protein kinase (p38 MAPK) phosphorylation increased in the DCM mice hearts and PTU treatment significantly reduced the phosphorylation levels, strongly suggesting that Dio2 up-regulation is involved in cardiac remodelling in DCM through activating the TH-signalling pathways involving Akt and p38 MAPK. Dio2 gene expression was also markedly up-regulated in the mice hearts developing similar eccentric hypertrophy after myocardial infarction. CONCLUSION Local hyperthyroidism via transcriptional up-regulation of the Dio2 gene may be an important underlying mechanism for the hypertrophic cardiac remodelling in DCM.
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MESH Headings
- Animals
- Antithyroid Agents/pharmacology
- Cardiomyopathy, Dilated/drug therapy
- Cardiomyopathy, Dilated/enzymology
- Cardiomyopathy, Dilated/genetics
- Cardiomyopathy, Dilated/physiopathology
- Cells, Cultured
- Cyclic AMP/metabolism
- Disease Models, Animal
- Female
- Gene Expression Profiling
- Gene Expression Regulation, Enzymologic
- Iodide Peroxidase/genetics
- Iodide Peroxidase/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Mutation
- Myocardium/enzymology
- Oligonucleotide Array Sequence Analysis
- Phosphorylation
- Propylthiouracil/pharmacology
- Proto-Oncogene Proteins c-akt/metabolism
- Transcription, Genetic
- Triiodothyronine/metabolism
- Troponin T/genetics
- Troponin T/metabolism
- Up-Regulation
- Ventricular Remodeling/drug effects
- p38 Mitogen-Activated Protein Kinases/metabolism
- Iodothyronine Deiodinase Type II
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