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Sample records for thyroid hormone deficiency

  1. IODIDE DEFICIENCY, THYROID HORMONES, AND NEURODEVELOPMENT

    Science.gov (United States)

    ABSTRACT BODY: Iodide is an essential nutrient for thyroid hormone synthesis. Severe iodide insufficiency during early development is associated with cognitive deficits. Environmental contaminants can perturb the thyroid axis and this perturbation may be more acute under conditio...

  2. Maternal iron deficiency alters circulating thyroid hormone levels in developing neonatal rats

    Science.gov (United States)

    Thyroid hormone insufficiency and iron deficiency (FeD) during fetal and neonatal life are both similarly deleterious to mammalian development suggesting a possible linkage between iron and thyroid hormone insufficiencies. Recent published data from our laboratory demonstrate a r...

  3. Dose-Response Analysis of Developmental Iodide Deficiency: Reductions in Thyroid Hormones and Impaired Hippocampal Synaptic Transmission

    Science.gov (United States)

    Iodide is an essential nutrient for thyroid hormone synthesis and severe iodide deficiency (ID) during early development is associated with neurological impairments. Several environmental contaminants can perturb the thyroid axis and this perturbation may be more acute under cond...

  4. Tissue-specific alterations in thyroid hormone homeostasis in combined Mct10 and Mct8 deficiency

    NARCIS (Netherlands)

    J. Müller (Julia); S. Mayerl (Steffen); T.J. Visser (Theo); V.M. Darras (Veerle); A. Boelen (Anita); L. Frappart (Lucien); L. Mariotta (Luca); F. Verrey; H. Heuer (Heike)

    2014-01-01

    textabstractThe monocarboxylate transporter Mct10 (Slc16a10; T-type amino acid transporter) facilitates the cellular transport of thyroid hormone (TH) and shows an overlapping expression with the wellestablished TH transporter Mct8. Because Mct8 deficiency is associated with distinct tissue-specific

  5. Tissue-specific alterations in thyroid hormone homeostasis in combined Mct10 and Mct8 deficiency

    NARCIS (Netherlands)

    Müller, Julia; Mayerl, Steffen; Visser, Theo J.; Darras, Veerle M.; Boelen, Anita; Frappart, Lucien; Mariotta, Luca; Verrey, Francois; Heuer, Heike

    2014-01-01

    The monocarboxylate transporter Mct10 (Slc16a10; T-type amino acid transporter) facilitates the cellular transport of thyroid hormone (TH) and shows an overlapping expression with the well-established TH transporter Mct8. Because Mct8 deficiency is associated with distinct tissue-specific

  6. Thyroid hormone: a “prime suspect” in human immuno deficiency ...

    African Journals Online (AJOL)

    Acquired Immunodeficiency Syndrome (AIDS) is the final and most serious stage of the disease caused by human immunodeficiency virus. The Immune system is the target of AIDS. We investigate presently any possible involvement of thyroid hormone, the deficiency of which gives rise to oedema and susceptibility to ...

  7. Consequences of monocarboxylate transporter 8 deficiency for renal transport and metabolism of thyroid hormones in mice

    NARCIS (Netherlands)

    M. Trajkovic-Arsic (Marija); T.J. Visser (Theo); V.M. Darras (Veerle); E.C.H. Friesema (Edith); B. Schlott (Bernhard); J. Mittag (Jens); K. Bauer (Karl); H. Heuer (Heike)

    2010-01-01

    textabstractPatients carrying inactivating mutations in the gene encoding the thyroid hormone transporting monocarboxylate transporter (MCT)-8 suffer from a severe form of psychomotor retardation and exhibit abnormal serum thyroid hormone levels. The thyroidal phenotype characterized by highserum

  8. Tetrac can replace thyroid hormone during brain development in mouse mutants deficient in the thyroid hormone transporter Mct8

    NARCIS (Netherlands)

    S. Horn (Sigrun); S. Kersseboom (Simone); S. Mayerl (Steffen); J. Müller (Julia); C. Groba (Claudia); M. Trajkovic-Arsic (Marija); T. Ackermann (Tobias); T.J. Visser (Theo); H. Heuer (Heike)

    2013-01-01

    textabstractThe monocarboxylate transporter 8 (MCT8) plays a critical role in mediating the uptake of thyroid hormones (THs) into the brain. In patients, inactivating mutations in the MCT8 gene are associated with a severe form of psychomotor retardation and abnormal serum TH levels. Here, we

  9. Long-term effects of growth hormone replacement therapy on thyroid function in adults with growth hormone deficiency.

    Science.gov (United States)

    Losa, Marco; Scavini, Marina; Gatti, Elisa; Rossini, Alessandro; Madaschi, Sara; Formenti, Ilaria; Caumo, Andrea; Stidley, Christine A; Lanzi, Roberto

    2008-12-01

    Clinical studies on the effect of growth hormone (GH) on thyroid function in patients with GH deficiency are contradictory. Further, the majority of published observations are limited to the first 6-12 months of GH replacement therapy. The aim of our study was to estimate the incidence of clinically relevant hypothyroidism in a cohort of patients with adult GH deficiency (AGHD) during long-term therapy with recombinant human GH (rhGH). The study was designed as a retrospective collection of data on thyroid function in 49 AGHD patients of whom 44 (90%) had multiple hormone deficiency. Thirty-seven patients (76%) were on stable levothyroxine (LT4) replacement therapy (HYPO), and 12 (24%) were euthyroid (EUT). Therapy with rhGH was started at a dose of 3.5 microg/kg body weight and adjusted according to insulin-like growth factor-I (IGF-I) levels. At baseline, 6 months, 12 months, and yearly thereafter we measured free triiodothyronine (fT3), free thyroxine (fT4), thyroid-stimulating hormone, and IGF-I. Study outcome was fT4 level below the normal range (9 pmol/L), irrespectively of fT3 or thyroid-stimulating hormone levels. During a follow-up of 115 patient-years, mean fT4 level decreased significantly, although remaining within the normal range (p = 0.0242; month 48 vs. baseline). The largest decrease was between baseline and month 6, when fT4 decreased of 1.43 pmol/L (95% confidence interval, 0.33-2.53) per 1 unit (microg/kg body weight) increase in rhGH dose. The incidence of hypothyroidism was 1.2 (HYPO group) and 6.7 (EUT group) events per 100 patient-years. We confirm that in patients with AGHD, rhGH therapy is associated with a small, although significant, decrement of fT4 in the first 6 months of replacement therapy. However, the incidence of hypothyroidism is low. Monitoring of thyroid function during rhGH therapy is advisable, particularly in the first year of therapy when the largest decrease in fT4 occurs.

  10. Effects of 1-year growth hormone replacement therapy on thyroid volume and function of the children and adolescents with idiopathic growth hormone deficiency.

    Science.gov (United States)

    Keskin, Meliksah; Bayramoglu, Elvan; Aycan, Zehra

    2017-10-26

    There are different opinions about the effects of growth hormone replacement therapy (GHRT) on thyroid function and volume. This study aimed to assess the effects of GHRT on thyroid volume and function in the children and adolescents with growth hormone (GH) deficiency. A total of 29 patients diagnosed with GH deficiency were enrolled in the study. The control group consisted of 29 cases matched for age, gender and pubertal period with the patients. Thyroid function tests and insulin-like growth factor levels were measured, simultaneously thyroid volumes were assessed by ultrasonography at the initiation period and at the end of GHRT. Thyroid volumes of the patient group was -0.55±1.1 standard deviations (SDs) initially; whereas at the end of 1 year it was found to be -0.29±1.29 SDs and both SDs of thyroid volumes did not differ significantly. The SDs of thyroid volume of the control group was -0.85±1.03 SDs initially and -0.72±0.85 SDs at the end of 1 year; and they did not differ significantly. On the other hand, after GHRT of 1 year, thyroid stimulating hormone (TSH) and free thyroxine (T4) levels decreased. It was observed that SDs of thyroid gland volumes did not change in GH deficient children and adolescents after GHRT.

  11. Accuracy of episodic autobiographical memory in children with early thyroid hormone deficiency using a staged event

    Directory of Open Access Journals (Sweden)

    Karen A. Willoughby

    2014-07-01

    Full Text Available Autobiographical memory (AM is a highly constructive cognitive process that often contains memory errors. No study has specifically examined AM accuracy in children with abnormal development of the hippocampus, a crucial brain region for AM retrieval. Thus, the present study investigated AM accuracy in 68 typically and atypically developing children using a staged autobiographical event, the Children's Autobiographical Interview, and structural magnetic resonance imaging. The atypically developing group consisted of 17 children (HYPO exposed during gestation to insufficient maternal thyroid hormone (TH, a critical substrate for hippocampal development, and 25 children with congenital hypothyroidism (CH, who were compared to 26 controls. Groups differed significantly in the number of accurate episodic details recalled and proportion accuracy scores, with controls having more accurate recollections of the staged event than both TH-deficient groups. Total hippocampal volumes and anterior hippocampal volumes were positively correlated with proportion accuracy scores, but not total accurate episodic details, in HYPO and CH. In addition, greater severity of TH deficiency predicted lower proportion accuracy scores in both HYPO and CH. Overall, these results indicate that children with early TH deficiency have deficits in AM accuracy and that the anterior hippocampus may play a particularly important role in accurate AM retrieval.

  12. Neonatal thyroid-stimulating hormone concentrations in Belgium: a useful indicator for detecting mild iodine deficiency?

    Directory of Open Access Journals (Sweden)

    Stefanie Vandevijvere

    Full Text Available It has been proposed that neonatal thyroid-stimulating hormone (TSH concentrations are a good indicator of iodine deficiency in the population. A frequency of neonatal TSH concentrations above 5 mU/L below 3% has been proposed as the threshold indicating iodine sufficiency. The objective of the present study was to evaluate feasibility and usefulness of nation-wide neonatal TSH concentration screening results to assess iodine status in Belgium. All newborns born in Belgium during the period 2009-2011 (n = 377713 were included in the study, except those suffering from congenital hypothyroidism and premature neonates. The frequency of neonatal TSH concentrations above 5 mU/L from 2009 to 2011 in Belgium fluctuated between 2.6 and 3.3% in the centres using the same TSH assay. There was a significant inverse association between neonatal TSH level and birth weight. The longer the duration between birth and screening, the lower the TSH level. Neonatal TSH levels were significantly lower in winter than in spring or autumn and significantly lower in spring and summer than in autumn while significantly higher in spring compared to summer. In conclusion, despite that pregnant women in Belgium are mildly iodine deficient, the frequency of neonatal TSH concentrations above 5 mU/L was very low, suggesting that the neonatal TSH threshold proposed for detecting iodine deficiency needs to be re-evaluated. Although neonatal TSH is useful to detect severe iodine deficiency, it should not be recommended presently for the evaluation of iodine status in mildly iodine deficient regions.

  13. Thyroid Hormone Treatment

    Science.gov (United States)

    ... THYROID HORMONES? Desiccated ( dried and powdered ) animal thyroid ( Armour ®), now mainly obtained from pigs, was the most ... Information A LISTING OF THE FDA-APPROVED MEDICINES PRODUCT FDA RATING MANUFACTURER Unithroid® AB (Stevens)*+ L-Thyroxin ...

  14. Hypoplastic thyroid, growth hormone deficiency, corneal opacities, cataract and hyperkeratotic skin disease: a possible new ichthyosis syndrome associated with endocrinopathies.

    Science.gov (United States)

    Pichler, Robert; Stelzer, Christoph; Berg, Jörg; Holzinger, Carl; Eckl, Katja Martina; Hennies, Hans Christian; Auböck, Josef

    2005-06-01

    A 56 year old man presented with ichthyosis vulgaris since early childhood, clinically characterised by fine scaling of the trunk and hyperkeratotic scales on the exterior surfaces of the upper and lower extremities. The patient also showed hypothyroidism due to hypoplastic thyroid, cataract, hypercholesterinemia with concommitant arcus cornealis and biliary concrements. Renal lithiasis caused by calcio-oxalate was additionally present. Endocrinological screening revealed growth hormone deficiency in the 1.55 m tall man-(secondary) osteoporosis was observed. The clinical symptomatology indicates that this case cannot be considered as a subtype of the inherited ichthyosis group, but suggests a new syndrome as a separate nosologic entity.

  15. Thyroid stimulating hormone and subclinical thyroid dysfunction

    International Nuclear Information System (INIS)

    Guo Yongtie

    2008-01-01

    Subclinical thyroid dysfunction has mild clinical symptoms. It is nonspecific and not so noticeable. It performs only for thyroid stimulating hormone rise and decline. The value of early diagnosis and treatment of thyroid stimulating hormone in subclinical thyroid dysfunction were reviewed. (authors)

  16. Thyroid hormone replacement therapy

    NARCIS (Netherlands)

    Wiersinga, W. M.

    2001-01-01

    Thyroid hormone replacement has been used for more than 100 years in the treatment of hypothyroidism, and there is no doubt about its overall efficacy. Desiccated thyroid contains both thyroxine (T(4)) and triiodothyronine (T(3)); serum T(3) frequently rises to supranormal values in the absorption

  17. Dysfunction of thyroid hormone synthesis and thyroid hormone transport

    OpenAIRE

    Ambrugger, Petra

    2010-01-01

    Thyroid hormones are essential in processes of growth and development especially in the development of the central nervous system. Malfunction in thyroid hormone synthesis or decrease in the availability of thyroid hormones can lead to diseases as for example congenital hypothyroidism. In this thesis genetic variations (mutations in the thyroid peroxidase gene, mutations in the monocarboxylate transporter 8 gene) as well as exogenic factors (endocrine disrupters) were examined, leading to d...

  18. Kinetics of thyroid hormones

    International Nuclear Information System (INIS)

    Inada, Mitsuo; Nishikawa, Mitsushige; Naito, Kimikazu; Ishii, Hitoshi; Tanaka, Kiyoshi

    1980-01-01

    Kinetics of thyroid hormones were outlined, and recent progress in metabolism of these hormones was also described. Recently, not only T 4 and T 3 but also rT 3 , 3,3'-T 2 , 3',5'-T 2 , and 3,5-T 2 can be measured by RIA. To clarify metabolic pathways of these hormones, metabolic clearance rate and production rate of these hormones were calculated. As single-compartment analysis was insufficient to clarify disappearance curves of thyroid hormones in blood such as T 3 and T 2 of which metabolic speed was so fast, multi-compartment analysis or non-compartment analysis were also performed. Thyroid hormones seemed to be measured more precisely by constant infusion method. At the first step of T 4 metabolism, T 3 was formed by 5'-monodeiodination of T 4 , and rT 3 was formed by 5-monodeiodination of T 4 . As metabolic pathways of T 3 and rT 3 , conversion of them to 3,3'-T 2 or to 3',5'-T 2 and 3,5-T 2 was supposed. This subject will be an interesting research theme in future. (Tsunoda, M.)

  19. Neurodevelopmental Consequences of Low-Level Thyroid Hormone Disruption Induced by Environmental Contaminants

    Science.gov (United States)

    Inadequate levels of thyroid hormone during critical developmental periods lead to stunted growth, mental retardation, and neurological 'cretinism'. Animal models of developmental thyroid hormone deficiency mirror well the impact of severe insults to the thyroid system. However, ...

  20. Thyroid hormone receptors in health and disease

    NARCIS (Netherlands)

    Boelen, A.; Kwakkel, J.; Fliers, E.

    2012-01-01

    Thyroid hormones (TH) play a key role in energy homeostasis throughout life. Thyroid hormone production and secretion by the thyroid gland is regulated via the hypothalamus-pituitary-thyroid (HPT)-axis. Thyroid hormone has to be transported into the cell, where it can bind to the thyroid hormone

  1. Thyroid hormone radioimmunoassay

    International Nuclear Information System (INIS)

    Rodriguez, S.; Richmond, M.; Quesada, S.; Lahaman, S.; Ramirez, A.; Herrera, J.F.

    1988-01-01

    The International Atomic Energy Agency (AIEA) is carrying out the ARCAL VIII Program 'Thiroid Hormone Readioimmunoassay'. The Immunoassay Laboratory of INCIENSA is in charge of this program, with the participation of four National Hospital System laboratories, which carried out Thyroxine (T4). Triodothyroxine (T3) and Thyroid Stimulating Hormone (TSH) assays with NETRIA Reagents (North East Thames Region Immunoassay Unit). The variability was shown to be between 9-20 per cent for T4, 12-22 per cent for TSH and 22-36 per cent for T3. The study also evaluated the quality of a tracer (T3-l125 and T4 l125) produced at INCIENSA. In this case the intrassay variability was 8,4 per cent for T3 and 6,8 per cent for T4 in 32 determinations evaluated during 6 months. It was concluded that the T4 and TSH tests but not the T3 test are valid and reproducible when NETRIA Ragents are used. The tracer made at INCIENSA can be used up to 6 weeks after the radioiodination with l125. A successful thyroid-related hormones quality control was defined in Costa Rica by taking advantage of the support of a prestigious international agency, the IAEA. (author). 13 refs, 4 figs

  2. [Influence of replacement growth hormone therapy (hGH) on pituitary-thyroid and pituitary-adrenal systems in prepubertal children with GH deficiency].

    Science.gov (United States)

    Vyshnevs'ka, O A; Bol'shova, O V

    2013-06-01

    Today, the most pathogenic therapy of GH deficiency is hGH replacement therapy. Replacement hGH therapy a highly effective method of growth correction in children with GH deficiency, but further investigations are necessary for timely detection of disturbances of other organs and systems. The authors reported that hGH therapy supressed thyroid and adrenal functions. Besides, most patients with GH deficiency have multiple defficiency of pituitary hormones (both TSH and ACTH), so hGH therapy can enhances hypothyroidism and hypoadrenalism. In the Department of Pediatric Endocrinology of the Institute of Endocrinology and Metabolism a great experience was accumulated in the treatment of GH deficiency children and in the study of the efficacy and safety of this treatment.

  3. Effects of growth hormone therapy on thyroid function of growth hormone-deficient adults with and without concomitant thyroxine-substituted central hypothyroidism

    DEFF Research Database (Denmark)

    Jørgensen, J O; Pedersen, S A; Laurberg, P

    1989-01-01

    of varying purity, often contaminated with TSH. Therefore, we conducted a double blind, placebo-controlled cross-over study of the effect of 4 months of biosynthetic human GH therapy (Norditropin; 2 IU/m2.day) on thyroid function in GH-deficient adults (8 females and 14 males; mean +/- SE age, 23.8 +/- 1......Administration of human GH to GH-deficient patients has yielded conflicting results concerning its impact on thyroid function, ranging from increased resting metabolic rate to induction of hypothyroidism. However, most studies have been casuistic or uncontrolled and have used pituitary-derived GH...

  4. Effects of growth hormone therapy on thyroid function of growth hormone-deficient adults with and without concomitant thyroxine-substituted central hypothyroidism

    DEFF Research Database (Denmark)

    Jørgensen, J O; Pedersen, S A; Laurberg, P

    1989-01-01

    Administration of human GH to GH-deficient patients has yielded conflicting results concerning its impact on thyroid function, ranging from increased resting metabolic rate to induction of hypothyroidism. However, most studies have been casuistic or uncontrolled and have used pituitary-derived GH...... of varying purity, often contaminated with TSH. Therefore, we conducted a double blind, placebo-controlled cross-over study of the effect of 4 months of biosynthetic human GH therapy (Norditropin; 2 IU/m2.day) on thyroid function in GH-deficient adults (8 females and 14 males; mean +/- SE age, 23.8 +/- 1...

  5. Glutathione deficiency induced by cystine and/or methionine deprivation does not affect thyroid hormone deiodination in cultured rat hepatocytes and monkey hepatocarcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Sato, K.; Robbins, J.

    1981-09-01

    To elucidate the recently advanced hypothesis that glutathione (L-gamma-glutamyl-L-cysteinyl glycine (GSH)) regulates deiodinating enzyme activities, accounting for the decreased conversion of T4 to T3 in the liver of fetal and starved animals, we investigated thyroid hormone metabolism in GSH-depleted neoplastic and normal hepatocytes. In monkey hepatocarcinoma cells, intracellular total GSH decreased below 10% of the control value (approximately 25 micrograms/mg protein) when cells were grown for 44 h in medium deficient in cystine and methionine or in cystine alone. The latter finding indicated that transsulfuration from methionine to cysteine was defective in these neoplastic cells. In primary cultured adult rat hepatocytes, on the other hand, the transsulfuration pathway was intact, and total GSH decreased below 10% of control (approximately 20 micrograms/mg protein) only in cells grown in cystine- and methionine-deficient medium. In both cell types, the oxidized GSH fraction remained constant (2-5% of total). Incubation with 125I-labeled T4 and T3, followed by chromatography, was used to evaluate 5-deiodination in hepatocarcinoma cells and both 5- and 5'-deiodination in normal hepatocytes. Deiodination was not decreased by GSH deficiency in either case, but was actually increased in hepatocarcinoma cells. This resulted from an increase in the Vmax of 5-deiodinase related to growth arrest. Diamide at 2 mM reversibly inhibited both 5'- and 5'-deiodination in rat hepatocytes, accompanied by decreased total GSH as well as increased GSH disulfide (27% of total). The data suggest that GSH is so abundant in the liver that hepatocytes can tolerate a greater than 90% decrease in intracellular concentration without any change in thyroid hormone deiodination and indicate that altered thyroid hormone metabolism in the fetus and in starvation cannot be accounted for by a decreased hepatic GSH concentration.

  6. Thyroid Hormone Deiodinases and Cancer

    Directory of Open Access Journals (Sweden)

    Antonio eBianco

    2012-06-01

    Full Text Available Deiodinases constitute a group of thioredoxin-containing selenoenzymes that play an important function in thyroid hormone homeostasis and control of thyroid hormone action. There are three known deiodinases: D1 and D2 activate the pro-hormone thyroxine (T4 to T3, the most active form of thyroid hormone, while D3 inactivates thyroid hormone and terminates T3 action. A number of studies indicate that deiodinase expression is altered in several types of cancers, suggesting that (i they may represent a useful cancer marker and/or (ii could play a role in modulating cell proliferation - in different settings thyroid hormone modulates cell proliferation. For example, although D2 is minimally expressed in human and rodent skeletal muscle, its expression level in rhabdomyosarcoma (RMS-13 cells is 3-4 fold higher. In basal cell carcinoma (BCC cells, sonic hedgehog (Shh-induced cell proliferation is accompanied by induction of D3 and inactivation of D2. Interestingly a 5-fold reduction in the growth of BCC in nude mice was observed if D3 expression was knocked down. A decrease in D1 activity has been described in renal clear cell carcinoma, primary liver cancer, lung cancer, and some pituitary tumors, while in breast cancer cells and tissue there is an increase in D1 activity. Furthermore D1 mRNA and activity were found to be decreased in papillary thyroid cancer while D1 and D2 activities were significantly higher in follicular thyroid cancer tissue, in follicular adenoma and in anaplastic thyroid cancer. It is conceivable that understanding how deiodinase dysregulation in tumor cells affect thyroid hormone signaling and possibly interfere with tumor progression could lead to new antineoplastic approaches.

  7. Thyroid hormone signaling in the hypothalamus

    NARCIS (Netherlands)

    Alkemade, Anneke; Visser, Theo J.; Fliers, Eric

    2008-01-01

    PURPOSE OF REVIEW: Proper thyroid hormone signaling is essential for brain development and adult brain function. Signaling can be disrupted at many levels due to altered thyroid hormone secretion, conversion or thyroid hormone receptor binding. RECENT FINDINGS: Mutated genes involved in thyroid

  8. Visual abilities at 6 months in preterm infants: impact of thyroid hormone deficiency and neonatal medical morbidity.

    Science.gov (United States)

    Simic, Nevena; Westall, Carol; Astzalos, Elizabeth V; Rovet, Joanne

    2010-03-01

    Preterm infants are at risk for neonatal morbidity, transiently reduced thyroid hormone (TH) levels, and impaired visual abilities. To determine the interrelationship between these factors, we measured TH levels in the period ex utero and compared their visual abilities with those of term infants at 6 months (corrected) of age. The preterm group consisted of 62 infants stratified by gestational age: Group A (23-26 weeks, n = 10), Group B (27-29 weeks, n = 23), Group C (30-32 weeks, n = 19), and Group D (33-35 weeks, n = 10). Controls were 31 healthy full-term infants. In the preterm group, free thyroxine, triiodothyronine, and thyroid-stimulating hormone levels were measured at 2 and 4 weeks of life and 40 weeks postconceptional age. All infants were assessed for visual acuity, contrast sensitivity, and color vision using electrophysiological techniques. Compared with controls, the preterm infants demonstrated reduced contrast sensitivity at low temporal frequencies and slower blue-yellow color processing. Groups did not differ from controls in visual acuity. In the preterm group, reduced contrast sensitivity and slow blue-yellow and red-green color vision processing were associated with low TH levels, low gestational age, and several medical morbidities. Our findings signify that some of the weak visual abilities in preterm infants can be accounted for, in part, by their reduced TH levels in the early postnatal period.

  9. Thyroid hormone synthesis and anti-thyroid drugs

    Indian Academy of Sciences (India)

    The inhibition of thyroid hormone synthesis is required for the treatment of hyperthyroidism and this can be achieved by one or more anti-thyroid drugs. The most widely used anti-thyroid drug methimazole (MMI) inhibits the production of thyroid hormones by irreversibly inactivating the enzyme TPO. Our studies show that the ...

  10. Thyroid hormone synthesis and anti-thyroid drugs: A bioinorganic ...

    Indian Academy of Sciences (India)

    The inhibition of thyroid hormone synthesis is required for the treatment of hyperthyroidism and this can be achieved by one or more anti-thyroid drugs. The most widely used anti-thyroid drug methimazole (MMI) inhibits the production of thyroid hormones by irreversibly inactivating the enzyme TPO. Our studies show that the ...

  11. Quantitative Adverse Outcome Pathway for Neurodevelopmental Effects of Thyroid Peroxidase-Induced Thyroid Hormone Synthesis Inhibition

    Science.gov (United States)

    Adequate levels of thyroid hormones (TH) are needed for proper brain development and deficiencies lead to adverse neurological outcomes in humans and in animal models. Environmental chemicals have been shown to disrupt TH levels, yet the relationship between developmental exposur...

  12. Quantitative Adverse Outcome Pathway for Neurodevelopmental Effects of Thyroid Peroxidase-Induced Thyroid Hormone Synthesis Inhibition

    Data.gov (United States)

    U.S. Environmental Protection Agency — Adequate levels of thyroid hormones (TH) are needed for proper brain development, deficiencies may lead to adverse neurological outcomes in humans and animal models....

  13. Effects of thyroid hormones on the heart.

    Science.gov (United States)

    Vargas-Uricoechea, Hernando; Bonelo-Perdomo, Anilsa; Sierra-Torres, Carlos Hernán

    2014-01-01

    Thyroid hormones have a significant impact on heart function, mediated by genomic and non-genomic effects. Consequently, thyroid hormone deficiencies, as well as excesses, are expected to result in profound changes in cardiac function regulation and cardiovascular hemodynamics. Thyroid hormones upregulate the expression of the sarcoplasmic reticulum calcium-activated ATPase and downregulate the expression of phospholamban. Overall, hyperthyroidism is characterized by an increase in resting heart rate, blood volume, stroke volume, myocardial contractility, and ejection fraction. The development of "high-output heart failure" in hyperthyroidism may be due to "tachycardia-mediated cardiomyopathy". On the other hand, in a hypothyroid state, thyroid hormone deficiency results in lower heart rate and weakening of myocardial contraction and relaxation, with prolonged systolic and early diastolic times. Cardiac preload is decreased due to impaired diastolic function. Cardiac afterload is increased, and chronotropic and inotropic functions are reduced. Subclinical thyroid dysfunction is relatively common in patients over 65 years of age. In general, subclinical hypothyroidism increases the risk of coronary heart disease (CHD) mortality and CHD events, but not of total mortality. The risk of CHD mortality and atrial fibrillation (but not other outcomes) in subclinical hyperthyroidism is higher among patients with very low levels of thyrotropin. Finally, medications such as amiodarone may induce hypothyroidism (mediated by the Wolff-Chaikoff), as well as hyperthyroidism (mediated by the Jod-Basedow effect). In both instances, the underlying cause is the high concentration of iodine in this medication. Copyright © 2014 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

  14. Thyroid Hormones as Renal Cell Cancer Regulators

    OpenAIRE

    Szyma?ski, ?ukasz; Matak, Damian; Bartnik, Ewa; Szczylik, Cezary; Czarnecka, Anna M.

    2016-01-01

    It is known that thyroid hormone is an important regulator of cancer development and metastasis. What is more, changes across the genome, as well as alternative splicing, may affect the activity of the thyroid hormone receptors. Mechanism of action of the thyroid hormone is different in every cancer; therefore in this review thyroid hormone and its receptor are presented as a regulator of renal cell carcinoma.

  15. Nuclear receptors for thyroid hormones

    International Nuclear Information System (INIS)

    Ricketts, M.H.; Groenewald, J. de W.; Wilson, B.D.

    1980-01-01

    The thyroid hormones, T 3 and T 4 , modulate a vast number of metabolic processes in mammalian tissues. High affinity, low capacity binding sites for T 3 and T 4 have been demonstrated in cell nuclei of target organs using both in vivo and in vitro labelling techniques. The displacement of [ 125 I]T 3 from nuclear binding sites by thyroid hormone analogues correlates well with the thyromimetic activities of the analogues tested. Dose-response relationships between T 3 occupancy and growth hormone secretion as a function of free T 3 concentration have been established with the GH 1 cell line. The equilibrium dissociation constant of the equation which describes how T 3 binds to the nuclei of intact cells is essentially the same as the free T 3 concentration that elicits the half-maximal biological response of the hormone. It is becoming apparent that these nuclear binding sites represent specific thyroid hormone receptors, whose function may be to regulate gene activity in target tissues. This report concerns the binding of the rat liver nuclear receptor to duplex and random coil DNA as well as to non-mammalian and synthetic DNAs. We postulate that the receptor binds in vivo to native DNA in the minor groove of the DNA helix

  16. Maintaining euthyroidism: fundamentals of thyroid hormone ...

    African Journals Online (AJOL)

    Thyroid-related pathologies, especially subclinical and clinical hypothyroidism, are commonly described in clinical practice. While illnesses related to aberrant thyroid hormone homeostasis are the most prevalent endocrinological conditions diagnosed, important aspects related to thyroid hormone physiology are often ...

  17. [Thyroid hormones and cardiovascular system].

    Science.gov (United States)

    Límanová, Zdeňka; Jiskra, Jan

    Cardiovascular system is essentially affected by thyroid hormones by way of their genomic and non-genomic effects. Untreated overt thyroid dysfunction is associated with higher cardiovascular risk. Although it has been studied more than 3 decades, in subclinical thyroid dysfunction the negative effect on cardiovascular system is much more controversial. Large meta-analyses within last 10 years have shown that subclinical hyperthyroidism is associated with higher cardiovascular risk than subclinical hypothyroidism. Conversely, in patients of age > 85 years subclinical hypothyroidism was linked with lower mortality. Therefore, subclinical hyperthyroidism should be rather treated in the elderly while subclinical hypothyroidism in the younger patients and the older may be just followed. An important problem on the border of endocrinology and cardiology is amiodarone thyroid dysfunction. Effective and safe treatment is preconditioned by distinguishing of type 1 and type 2 amiodarone induced hyperthyroidism. The type 1 should be treated with methimazol, therapeutic response is prolonged, according to recent knowledge immediate discontinuation of amiodarone is not routinely recommended and patient should be usually prepared to total thyroidectomy, or rather rarely 131I radioiodine ablation may be used if there is appropriate accumulation. In the type 2 there is a promt therapeutic response on glucocorticoids (within 1-2 weeks) with permanent remission or development of hypothyroidism. If it is not used for life-threatening arrhytmias, amiodarone may be discontinuated earlier (after several weeks). Amiodarone induced hypothyroidism is treated with levothyroxine without amiodarone interruption.Key words: amiodarone induced thyroid dysfunction - atrial fibrillation - cardiovascular risk - heart failure - hyperthyroidism - hypothyroidism - thyroid stimulating hormone.

  18. Thyroid Hormone Regulation of Metabolism

    Science.gov (United States)

    Mullur, Rashmi; Liu, Yan-Yun

    2014-01-01

    Thyroid hormone (TH) is required for normal development as well as regulating metabolism in the adult. The thyroid hormone receptor (TR) isoforms, α and β, are differentially expressed in tissues and have distinct roles in TH signaling. Local activation of thyroxine (T4), to the active form, triiodothyronine (T3), by 5′-deiodinase type 2 (D2) is a key mechanism of TH regulation of metabolism. D2 is expressed in the hypothalamus, white fat, brown adipose tissue (BAT), and skeletal muscle and is required for adaptive thermogenesis. The thyroid gland is regulated by thyrotropin releasing hormone (TRH) and thyroid stimulating hormone (TSH). In addition to TRH/TSH regulation by TH feedback, there is central modulation by nutritional signals, such as leptin, as well as peptides regulating appetite. The nutrient status of the cell provides feedback on TH signaling pathways through epigentic modification of histones. Integration of TH signaling with the adrenergic nervous system occurs peripherally, in liver, white fat, and BAT, but also centrally, in the hypothalamus. TR regulates cholesterol and carbohydrate metabolism through direct actions on gene expression as well as cross-talk with other nuclear receptors, including peroxisome proliferator-activated receptor (PPAR), liver X receptor (LXR), and bile acid signaling pathways. TH modulates hepatic insulin sensitivity, especially important for the suppression of hepatic gluconeogenesis. The role of TH in regulating metabolic pathways has led to several new therapeutic targets for metabolic disorders. Understanding the mechanisms and interactions of the various TH signaling pathways in metabolism will improve our likelihood of identifying effective and selective targets. PMID:24692351

  19. Thyroid hormones and cardiac arrhythmias

    Czech Academy of Sciences Publication Activity Database

    Tribulová, N.; Knezl, V.; Shainberg, A.; Seki, S.; Soukup, Tomáš

    2010-01-01

    Roč. 52, 3-4 (2010), s. 102-112 ISSN 1537-1891 R&D Projects: GA ČR(CZ) GA304/08/0256 Grant - others:VEGA(SK) 2/0049/09; APVV(SK) 51-059505; APVV(SK) 51-017905 Institutional research plan: CEZ:AV0Z50110509 Keywords : thyroid hormone * arrhythmias * ion channels * connexin-43 Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 2.174, year: 2010

  20. Thyroid hormone and seasonal rhythmicity

    Directory of Open Access Journals (Sweden)

    Hugues eDardente

    2014-02-01

    Full Text Available Living organisms show seasonality in a wide array of functions such as reproduction, fattening, hibernation and migration. At temperate latitudes, changes in photoperiod maintain the alignment of annual rhythms with predictable changes in the environment. The appropriate physiological response to changing photoperiod in mammals requires retinal detection of light and pineal secretion of melatonin, but extraretinal detection of light occurs in birds. A common mechanism across all vertebrates is that these photoperiod-regulated systems alter hypothalamic thyroid hormone conversion. Here we review the evidence that a circadian clock within the pars tuberalis of the adenohypophysis links photoperiod decoding to local changes of thyroid hormone signalling within the medio-basal hypothalamus through a conserved thyrotropin/deiodinase axis. We also focus on recent findings which indicate that, beyond the photoperiodic control of its conversion, thyroid hormone might also be involved in longer term timing processes of seasonal programs. Finally, we examine the potential implication of kisspeptin and RFRP3, two RF-amide peptides expressed within the medio-basal hypothalamus, in seasonal rhythmicity.

  1. Thyroid Hormone Receptor beta Mediates Acute Illness-Induced Alterations in Central Thyroid Hormone Metabolism

    NARCIS (Netherlands)

    Boelen, Anita; Kwakkel, Joan; Chassande, Olivier; Fliers, Eric

    2009-01-01

    Acute illness in mice profoundly affects thyroid hormone metabolism in the hypothalamus and pituitary gland. It remains unknown whether the thyroid hormone receptor (TR)-beta is involved in these changes. In the present study, we investigated central thyroid hormone metabolism during

  2. Role of maternal thyroid hormones in the developing neocortex and during human evolution

    Science.gov (United States)

    Stenzel, Denise; Huttner, Wieland B.

    2013-01-01

    The importance of thyroid hormones during brain development has been appreciated for many decades. In humans, low levels of circulating maternal thyroid hormones, e.g., caused by maternal hypothyroidism or lack of iodine in diet, results in a wide spectrum of severe neurological defects, including neurological cretinism characterized by profound neurologic impairment and mental retardation, underlining the importance of the maternal thyroid hormone contribution. In fact, iodine intake, which is essential for thyroid hormone production in the thyroid gland, has been related to the expansion of the brain, associated with the increased cognitive capacities during human evolution. Because thyroid hormones regulate transcriptional activity of target genes via their nuclear thyroid hormone receptors (THRs), even mild and transient changes in maternal thyroid hormone levels can directly affect and alter the gene expression profile, and thus disturb fetal brain development. Here we summarize how thyroid hormones may have influenced human brain evolution through the adaptation to new habitats, concomitant with changes in diet and, therefore, iodine intake. Further, we review the current picture we gained from experimental studies in rodents on the function of maternal thyroid hormones during developmental neurogenesis. We aim to evaluate the effects of maternal thyroid hormone deficiency as well as lack of THRs and transporters on brain development and function, shedding light on the cellular behavior conducted by thyroid hormones. PMID:23882187

  3. Thyroid hormone therapy following the thyroidectomy for thyroid carcinoma

    International Nuclear Information System (INIS)

    Horster, F.A.

    1986-01-01

    Medication with thyroid hormones following total thyroidectomy for thyroid carcinoma is based on the following principles: 1. The patient is informed about the lifelong necessity of taking a thyroid hormones daily before breakfast. This hormone must be given orally and its bioligical effect is identical with that of the tyhroid hormone secreted by the healthy thyroid gland. 2. The daily dosage of thyroid hormones may be assessed on the basis of the following parameters: a) the patient's clinical euthyroidism, b) suppression of thyrotropic activity, c) unrestricted tolerance of the preparation. 3. The in vitro parameters associated with optimal medication should be within the following ranges: Thyroxine value (TT4 or FT4): above the normal range, triiodothyronine value (TT3 or FT3): within the upper normal range and thyrotropin value (TSH 'ultrasensitive' or TRH-test): suppressed. (orig.) [de

  4. Thyroid hormone metabolism in poultry

    Directory of Open Access Journals (Sweden)

    Darras V.M.

    2000-01-01

    Full Text Available Thyroid hormone (TH receptors preferentially bind 3.5,3'-triiodothyronine (T3. Therefore the metabolism of thyroxine (T4 secreted by the thyroid gland in peripheral tissues, resulting in the production and degradation of receptor-active T3, plays a major role in thyroid function. The most important metabolic pathway for THs is deiodination. Another important pathway is sulfation, which is a reversible pathway that has been shown to interact with TH deiodination efficiency. The enzymes catalysing TH deiodination consist of three types. Type 1 deiodinase (D1 catalyses both outer ring (ORD and inner ring deiodinalion (IRD. Type II deiodinase (D2 only catalyses ORD while type III (D3 only catalyses IRD. The three chicken deiodinase cDNAs have been cloned recently. These enzymes all belong to the family of selenoproteins. Ontogenetic studies show that the availability of deiodinases is regulated in a tissue specific and developmental stage dependent way. Characteristic for the chicken is the presence of very high levels off, inactivating D3 enzyme in the embryonic liver. Hepatic D3 is subject to acute regulation in a number of situations. Both growth hormone and glucocorticoid injection rapidly decrease hepatic D3 levels, hereby increasing plasma T3 without affecting hepatic D1 levels. The inhibition of D3 seems to be regulated mainly at the level of D3 gene transcription. The effect of growth hormone on D3 expression persists throughout life, while glucocorticoids start to inhibit hepatic D1 expression in posthatch chickens. Food restriction in growing chickens increases hepatic D3 levels. This contributes to the decrease in plasma T3 necessary to reduce energy loss. Refeeding restores hepatic D3 and plasma T3 to control levels within a few hours. It can be concluded that the tissue and time dependent regulation of the balance between TH activating and inactivating enzymes plays an essential role in the control of local T3 availability and hence in

  5. Maintaining Euthyroidism: Fundamentals of Thyroid Hormone ...

    African Journals Online (AJOL)

    In fact, while thyroid hormones, i.e. triiodothyronine. (T3) and thyroxine (T4), play a ... hormone regulation, iodine metabolism, and the clinical management of thyroid related pathology, the current paper provides a physiological and clinical overview of ...... Surks MI, Goswami G, Daniels GH. The thyrotropin reference range ...

  6. THYROID HORMONE: A “PRIME SUSPECT” IN HUMAN IMMUNO ...

    African Journals Online (AJOL)

    Daniel Owu

    .nips; www.cas.org. THYROID HORMONE: A “PRIME SUSPECT” IN HUMAN IMMUNO. DEFICIENCY VIRUS (HIV/AIDS) PATIENTS? K. AMADI, A. M. SABO, O. O. OGUNKEYE and F. S. OLUWOLE. 1. Department of Human Physiology, College ...

  7. Thyroid Hormone Receptor Mutations in Cancer and Resistance to Thyroid Hormone: Perspective and Prognosis

    Directory of Open Access Journals (Sweden)

    Meghan D. Rosen

    2011-01-01

    Full Text Available Thyroid hormone, operating through its receptors, plays crucial roles in the control of normal human physiology and development; deviations from the norm can give rise to disease. Clinical endocrinologists often must confront and correct the consequences of inappropriately high or low thyroid hormone synthesis. Although more rare, disruptions in thyroid hormone endocrinology due to aberrations in the receptor also have severe medical consequences. This review will focus on the afflictions that are caused by, or are closely associated with, mutated thyroid hormone receptors. These include Resistance to Thyroid Hormone Syndrome, erythroleukemia, hepatocellular carcinoma, renal clear cell carcinoma, and thyroid cancer. We will describe current views on the molecular bases of these diseases, and what distinguishes the neoplastic from the non-neoplastic. We will also touch on studies that implicate alterations in receptor expression, and thyroid hormone levels, in certain oncogenic processes.

  8. Thyroid hormone resistance syndrome due to mutations in the thyroid hormone receptor alpha gene (THRA)

    NARCIS (Netherlands)

    Tylki-Szymanska, A.; Acuna Hidalgo, R.; Krajewska-Walasek, M.; Lecka-Ambroziak, A.; Steehouwer, M.; Gilissen, C.F.; Brunner, H.G.; Jurecka, A.; Rozdzynska-Swiatkowska, A.; Hoischen, A.; Chrzanowska, K.H.

    2015-01-01

    BACKGROUND: Resistance to thyroid hormone is characterised by a lack of response of peripheral tissues to the active form of thyroid hormone (triiodothyronine, T3). In about 85% of cases, a mutation in THRB, the gene coding for thyroid receptor beta (TRbeta), is the cause of this disorder. Recently,

  9. Thyroid hormone synthesis and anti-thyroid drugs: A bioinorganic chemistry approach

    OpenAIRE

    Roy, Gouriprasanna; Mugesh, G

    2006-01-01

    Hydrogen peroxide, generated by thyroid oxidase enzymes, is a crucial substrate for the thyroid peroxidase (TPO)-catalysed biosynthesis of thyroid hormones, thyroxine (T4) and triiodothyronine (T3) in the thyroid gland. It is believed that the $H_2O_2$ generation is a limiting step in thyroid hormone synthesis. Therefore, the control of hydrogen peroxide concentration is one of the possible mechanisms for the inhibition of thyroid hormone biosynthesis. The inhibition of thyroid hormone synthe...

  10. 21 CFR 862.1690 - Thyroid stimulating hormone test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Thyroid stimulating hormone test system. 862.1690... Systems § 862.1690 Thyroid stimulating hormone test system. (a) Identification. A thyroid stimulating hormone test system is a device intended to measure thyroid stimulating hormone, also known as...

  11. Regulation of Thyroid Hormone Bioactivity in Health and Disease

    NARCIS (Netherlands)

    R.P. Peeters (Robin)

    2005-01-01

    textabstractTThyroid hormone plays an essential role in a variety of metabolic processes in the human body. Examples are the effects of thyroid hormone on metabolism and on the heart. The production of thyroid hormone by the thyroid is regulated by thyroid stimulating hormone (TSH) via the TSH

  12. Thyroid Hormones and Glycaemic Indices in Types 1 and 2 ...

    African Journals Online (AJOL)

    Studies comparing the relationship between thyroid hormones and the glycaemic indices in Types 1 and 2 diabetics are scanty. This study compared the relationship between thyroid hormones and glycaemic indices in Type 1 and Type 2 diabetics on various therapies. The thyroid hormones, thyroid stimulating hormone ...

  13. Unexpected Elevated Free Thyroid Hormones in Pregnancy.

    Science.gov (United States)

    Teti, Claudia; Nazzari, Elena; Galletti, Marina Raffaella; Mandolfino, Mattia Grazia; Pupo, Francesca; Pesce, Giampaola; Lillo, Flavia; Bagnasco, Marcello; Benvenga, Salvatore

    2016-11-01

    The use of thyrotropin and free thyroid hormone assays to evaluate thyroid function is widespread, but in some situations the results are inconsistent with the patient's thyroid status. A 35-year-old woman with a known diagnosis of chronic autoimmune thyroiditis was referred to the authors' clinic at week 26 of her second pregnancy. The patient was clinically euthyroid. Consistent with this, her serum thyrotropin (TSH) was normal (0.79 mIU/L), but she had elevated free thyroid hormones-free triiodothyronine (fT3) and free thyroxine (fT4)-as determined by a one-step chemiluminescent assay. The patient was taking levothyroxine replacement therapy (125 μg/day), and the dose was confirmed. Previous blood tests showed concordance between TSH and free thyroid hormone values. The patient was followed up throughout gestation and at 12 months postpartum. During gestation, her free thyroid hormones remained high using one-step methods, while the total thyroid hormone concentration values were within the reference range, in agreement with the TSH values. Postpartum fT4 and fT3 values returned progressively to normality, in agreement with the TSH values. The presence of circulating thyroid hormone autoantibodies (THAb) was hypothesized, which are known to interfere, although to a variable extent, with thyroid hormone one-step assays. Using stored frozen sera, this hypothesis was confirmed indirectly by measuring normal levels of fT3 and fT4 with a two-step method, and directly by demonstrating THAb against the two hormones. Despite their relative rarity, circulating THAb may be suspected when laboratory data are not consistent and contrast with the clinical picture. To the authors' knowledge, no previous case of transient appearance of THAb in pregnancy has been described.

  14. Thyroid Hormone Receptor Mutations in Cancer and Resistance to Thyroid Hormone: Perspective and Prognosis

    OpenAIRE

    Meghan D. Rosen; Martin L. Privalsky

    2011-01-01

    Thyroid hormone, operating through its receptors, plays crucial roles in the control of normal human physiology and development; deviations from the norm can give rise to disease. Clinical endocrinologists often must confront and correct the consequences of inappropriately high or low thyroid hormone synthesis. Although more rare, disruptions in thyroid hormone endocrinology due to aberrations in the receptor also have severe medical consequences. This review will focus on the afflictions tha...

  15. Thyroid hormone resistance misdiagnosed as Graves' disease

    Directory of Open Access Journals (Sweden)

    Manish Gutch

    2017-01-01

    Full Text Available Resistance to thyroid hormone (RTH syndrome is a very rare disorder characterized by mutations of the thyroid hormone receptor beta and is usually inherited as an autosomal dominant trait. Patients with RTH are usually euthyroid but rarely may present with signs and symptoms consistent with hyperthyroidism. Here, we describe the case of a young girl with goiter who was previously misdiagnosed to have hyperthyroidism and was subsequently diagnosed to be suffering from RTH.

  16. Impact of Low-Level Thyroid Hormone Disruption Induced by Propylthiouracil on Brain Development and Function.*

    Science.gov (United States)

    The critical role of thyroid hormone (TH) in brain development is well established, severe deficiencies leading to significant neurological dysfunction. Much less information is available on more modest perturbations of TH on brain function. The present study induced varying degr...

  17. Gene Expression as a Biomarker of Effect of Thyroid Hormone Action in Developing Brain: Relation to Serum Hormones.

    Science.gov (United States)

    Disruption of thyroid hormone (TH) homeostasis is a known effect of environmental contaminants. Although animal models of developmental TH deficiency can predict the impact of severe insults to the thyroid system, the effects of moderate TH insufficiencies have proved more diffic...

  18. Control of Pituitary Thyroid-stimulating Hormone Synthesis and Secretion by Thyroid Hormones during Xenopus Metamorphosis

    Science.gov (United States)

    Serum thyroid hormone (TH) concentrations in anuran larvae rise rapidly during metamorphosis. Such a rise in an adult anuran would inevitably trigger a negative feedback response resulting in decreased synthesis and secretion of thyroid-stimulating hormone (TSH) by the pituitary....

  19. The thyroid nodule. Thyrotropin and peripheral thyroid hormones; Der Schilddruesenknoten. TSH und periphere Hormone

    Energy Technology Data Exchange (ETDEWEB)

    Zimny, M. [Klinikum Hanau (Germany). Inst. fuer Nuklearmedizin

    2008-09-15

    Thyrotropin, free triodothyronine and thyroxine represent the standard serological parameters for the diagnostic work-up of the thyroid but only a minority of thyroid nodules present with subclinical or overt thyroid disorders. Besides a review of the regulation and principle of function of thyroid hormones as well as the effects of subclinical or overt hyperthyroidism, the significant role of these parameters beyond the assessment of hyperthyroidism in thyroid nodules is discussed. There is evidence that the level of thyrotropin within the normal range is predictive for the relevance of autonomous functioning nodules and the risk of malignancy of non-functioning thyroid nodules. Furthermore, the ratio of triodothyronine and thyroxine indicates the etiology of hyperthyroidism. Thyrotropin represents the main parameter to determine the adequate dose of thyroid hormone therapy of thyroid nodules. (orig.)

  20. Interdependence of thyroglobulin processing and thyroid hormone export in the mouse thyroid gland.

    Science.gov (United States)

    Weber, Jonas; McInnes, Joseph; Kizilirmak, Cise; Rehders, Maren; Qatato, Maria; Wirth, Eva K; Schweizer, Ulrich; Verrey, Francois; Heuer, Heike; Brix, Klaudia

    2017-08-01

    Thyroid hormone (TH) target cells need to adopt mechanisms to maintain sufficient levels of TH to ensure regular functions. This includes thyroid epithelial cells, which generate TH in addition to being TH-responsive. However, the cellular and molecular pathways underlying thyroid auto-regulation are insufficiently understood. In order to investigate whether thyroglobulin processing and TH export are sensed by thyrocytes, we inactivated thyroglobulin-processing cathepsins and TH-exporting monocarboxylate transporters (Mct) in the mouse. The states of thyroglobulin storage and its protease-mediated processing and degradation were related to the levels of TH transporter molecules by immunoblotting and immunofluorescence microscopy. Thyroid epithelial cells of cathepsin-deficient mice showed increased Mct8 protein levels at the basolateral plasma membrane domains when compared to wild type controls. While the protein amounts of the thyroglobulin-degrading cathepsin D remained largely unaffected by Mct8 or Mct10 single-deficiencies, a significant increase in the amounts of the thyroglobulin-processing cathepsins B and L was detectable in particular in Mct8/Mct10 double deficiency. In addition, it was observed that larger endo-lysosomes containing cathepsins B, D, and L were typical for Mct8- and/or Mct10-deficient mouse thyroid epithelial cells. These data support the notion of a crosstalk between TH transporters and thyroglobulin-processing proteases in thyroid epithelial cells. We conclude that a defect in exporting thyroxine from thyroid follicles feeds back positively on its cathepsin-mediated proteolytic liberation from the precursor thyroglobulin, thereby adding to the development of auto-thyrotoxic states in Mct8 and/or Mct10 deficiencies. The data suggest TH sensing molecules within thyrocytes that contribute to thyroid auto-regulation. Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.

  1. Thyroid Hormones, Oxidative Stress, and Inflammation

    OpenAIRE

    Mancini, Antonio; Di Segni, Chantal; Raimondo, Sebastiano; Olivieri, Giulio; Silvestrini, Andrea; Meucci, Elisabetta; Curr?, Diego

    2016-01-01

    Inflammation and oxidative stress (OS) are closely related processes, as well exemplified in obesity and cardiovascular diseases. OS is also related to hormonal derangement in a reciprocal way. Among the various hormonal influences that operate on the antioxidant balance, thyroid hormones play particularly important roles, since both hyperthyroidism and hypothyroidism have been shown to be associated with OS in animals and humans. In this context, the nonthyroidal illness syndrome (NTIS) that...

  2. Does normal thyroid gland by ultrasonography match with normal serum thyroid hormones and negative thyroid antibodies?

    Science.gov (United States)

    Trimboli, P; Rossi, F; Condorelli, E; Laurenti, O; Ventura, C; Nigri, G; Romanelli, F; Guarino, M; Valabrega, S

    2010-10-01

    Few papers have shown that a hypoechoic appearance of the thyroid gland at ultrasonography (US) is related to a hypofunction and serum positivity of thyroid antibodies (T-Ab). However, it is not ascertained if normal thyroid appearance at US correspond to normal thyroid laboratory tests. The aim of this study was to assess the value of normal thyroid at US in predicting normal thyroid hormones and negative T-Ab in a cohort of 48 adult patients. All patients (37 females and 11 males) were referred to our hospital to undergo their first thyroid US examination, followed by a thyroid function evaluation. All subjects had normal thyroid gland at US. As a control group 65 patients with hypoechoic and inhomogeneous thyroid gland were enrolled. All 48 patients had normal free-T (3) and free-T (4) levels. While 41 patients (85.4%) showed normal TSH, in 7 subjects (14.6%) TSH was elevated and a significant (p thyroid volume or BMI. The multivariate model showed that only BMI was significantly correlated to thyroid volume (p thyroid recorded by US matches with normal thyroid laboratory assessment to a large degree. These preliminary data need to be confirmed in a prospective study and in a larger series and should suggest the evaluation of thyrotropin and thyroid antibodies in subjects with normal thyroid gland as assessed by US. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York.

  3. The importance of thyroid hormone sulfation during fetal development

    NARCIS (Netherlands)

    M.H.A. Kester (Monique)

    2001-01-01

    textabstractNormal fetal development requires the presence of thyroid hormone. Disruption of any of the processes regulating the bioavailability of thyroid hormone may contribute to congenital anomalies. This thesis is focussed a) on the importance of thyroid hormone sulfation during

  4. H9c2 cardiomyoblasts produce thyroid hormone

    NARCIS (Netherlands)

    Meischl, Christof; Buermans, Henk P.; Hazes, Thierry; Zuidwijk, Marian J.; Musters, René J. P.; Boer, Christa; van Lingen, Arthur; Simonides, Warner S.; Blankenstein, Marinus A.; Dupuy, Corrine; Paulus, Walter J.; Hack, C. Erik; Ris-Stalpers, Carrie; Roos, Dirk; Niessen, Hans W. M.

    2008-01-01

    Thyroid hormone acts on a wide range of tissues. In the cardiovascular system, thyroid hormone is an important regulator of cardiac function and cardiovascular hemodynamics. Although some early reports in the literature suggested an unknown extrathyroidal source of thyroid hormone, it is currently

  5. Thyroid disorders in mild iodine deficiency

    DEFF Research Database (Denmark)

    Laurberg, P; Nøhr, S B; Pedersen, K M

    2000-01-01

    in elderly subjects, especially women, with risk of cardiac arrhythmias, osteoporosis, and muscle wasting. The hyperthyroidism is caused by autonomous nodular growth and function of the thyroid gland and it is accompanied by a high frequency of goiter. Pregnant women and small children are not immediately...... endangered but the consequences of severe iodine deficiency for brain development are grave and a considerable safety margin is advisable. Moreover, a shift toward less malignant types of thyroid cancer and a lower radiation dose to the thyroid in case of nuclear fallout support that mild-to-moderate iodine...

  6. Association of High Vitamin D Status with Low Circulating Thyroid-Stimulating Hormone Independent of Thyroid Hormone Levels in Middle-Aged and Elderly Males

    Directory of Open Access Journals (Sweden)

    Qingqing Zhang

    2014-01-01

    Full Text Available Background. A recent study has reported that high circulating 25-hydroxyvitamin D [25(OHD] is associated with low circulating thyroid-stimulating hormone (TSH levels, but only in younger individuals. The goal of the present study was to explore the relationship between vitamin D status and circulating TSH levels with thyroid autoimmunity and thyroid hormone levels taken into consideration in a population-based health survey of middle-aged and elderly individuals. Methods. A total of 1,424 Chinese adults, aged 41–78 years, were enrolled in this cross-sectional study. Serum levels of 25(OHD, TSH, thyroid hormones, and thyroid autoantibodies were measured. Results. The prevalence of vitamin D insufficiency was 94.29% in males and 97.22% in females, and the prevalence of vitamin D deficiency was 55.61% in males and 69.64% in females. Vitamin D status was not associated with positive thyroid autoantibodies after controlling for age, gender, body mass index, and smoking status. Higher 25(OHD levels were associated with lower TSH levels after controlling for age, FT4 and FT3 levels, thyroid volume, the presence of thyroid nodule(s, and smoking status in males. Conclusion. High vitamin D status in middle-aged and elderly males was associated with low circulating TSH levels independent of thyroid hormone levels.

  7. Visualisation of thyroid hormone synthesis by ion imaging

    Science.gov (United States)

    Audinot, J. N.; Senou, M.; Migeon, H.-N.; Many, M.-C.

    2008-12-01

    The main function of the thyroid gland is to make hormones, T4 and T3, which are essential for the regulation of metabolic processes throughout the body. Caveolae harbour is the key enzymes involved in this iodide organification. The analyses of thyroids from normal mice and caveolin-1 Knockout mice (mice deficient in caveolin) have been performed using the SIMS imaging. In the thyroid of control mice, the epithelium is homogeneous and iodine ( 127I) is observed in the follicle lumen. In Knockout mice, we observe an accumulation of intracellular vesicles and apoptotic nuclei resulting from oxidative stress due to H 2O 2 overproduction also inducing apical lesions of the thyrocytes, at the site of iodine organification and H 2O 2 generation. We also observe in the Knockout mice an accumulation of 127I in the cellular cytoplasm and an absence of the iodine in some follicular lumina, indicating a problem at the level of iodine organification.

  8. Relationship between Thyroid Hormone levels and Hyperthyroid ...

    African Journals Online (AJOL)

    Objective: Assessment of thyrotoxic patients often involves laboratory and clinical evaluation. We have therefore investigated the relationship between the magnitude of hyperthyroid symptoms and thyroid hormone levels in a set of newly diagnosed thyrotoxic patients. Methods: Fifteen subjects with untreated, newly ...

  9. Genetic features of thyroid hormone receptors

    Indian Academy of Sciences (India)

    Abstract. Thyroid hormone receptors (TR) are prototypes of nuclear transcription factors that regulate the expression of target genes. These receptors play an important role in many physiological processes. Moreover, a dysfunction of these proteins is often implicated in several human diseases and malignancies. Here we ...

  10. Tissue thyroid hormone levels in critical illness

    NARCIS (Netherlands)

    R.P. Peeters (Robin); S.D. van Geyten (Serge Der); P.J. Wouters (Pieter); V.M. Darras (Veerle); H. van Toor (Hans); E. Kaptein (Ellen); T.J. Visser (Theo); G. van den Berghe (Greet)

    2005-01-01

    textabstractContext: Pronounced alterations in serum thyroid hormone levels occur during critical illness. T3 decreases and rT3 increases, the magnitudes of which are related to the severity of disease. It is unclear whether these changes are associated with decreased tissue T3 concentrations and,

  11. Progressive pituitary hormone deficiency following radiation therapy in adults

    International Nuclear Information System (INIS)

    Loureiro, Rafaela A.; Vaisman, Mario

    2004-01-01

    Hypopituitarism can be caused by radiation therapy, even when it is not directly applied on the hypothalamic-pituitary axis, and can lead to anterior pituitary deficiency mainly due to hypothalamic damage. The progressive loss of the anterior pituitary hormones usually occurs in the following order: growth hormone, gonadotropin hormones, adrenocorticotropic hormone and thyroid-stimulating hormone. Although there are several different tests available to confirm anterior pituitary deficiency, this paper will focus on the gold standard tests for patients submitted to radiation therapy. We emphasize that the decline of anterior pituitary function is time- and dose-dependent with some variability among the different axes. Therefore, awareness of the need of a joint management by endocrinologists and oncologists is essential to improve treatment and quality of life of the patients. (author)

  12. The chicken c-erbA alpha-product induces expression of thyroid hormone-responsive genes in 3,5,3'-triiodothyronine receptor-deficient rat hepatoma cells

    DEFF Research Database (Denmark)

    Muñoz, A; Höppner, W; Sap, J

    1990-01-01

    To determine the capacity of the chicken c-erbA (cTR-alpha) gene product in regulating expression of known thyroid hormone-responsive genes, both the cTR-alpha and the viral v-erbA genes were expressed in FAO cells, a rat hepatoma cell line defective for functional thyroid hormone receptors. Upon...... nuclear expression of the cTR-alpha protein the cells become responsive to thyroid hormone, as detected by expression of a number of genes (malic enzyme, phosphoenolpyruvate carboxykinase, and Na+/K(+)-ATPase) reported to be indirectly induced by the hormone in vivo. In addition, our data show that the c......-erbA product directly activates the Moloney murine leukemia virus promoter in a ligand-dependent manner. The data show that the chicken c-erbA-alpha protein can modulate the expression of rat genes under either direct or indirect control by thyroid hormone....

  13. Growth and development in a child with resistance to thyroid hormone and ectopic thyroid gland.

    Science.gov (United States)

    Heather, Natasha; Hall, Kate; Neas, Katherine; Potter, Howard; Wiltshire, Esko

    2012-03-01

    Resistance to thyroid hormone is an uncommon problem, which has rarely been associated with thyroid dysgenesis. We report a case with both thyroid gland ectopy and resistance to thyroid hormone and, thus, a reduced capacity to produce and respond to thyroid hormone. The patient presented at 2 years of age with developmental delay, dysmorphic features, and elevation in both thyroxine and thyrotropin. We document her response to therapy with thyroxine, with particular regard to her growth and development. Persistent elevation of thyrotropin is commonly recognized during treatment of congenital hypothyroidism. Resistance to thyroid hormone may be an important additional diagnosis to consider in cases where thyrotropin remains persistently elevated.

  14. Thyroid Hormone Signaling in the Mouse Retina.

    Directory of Open Access Journals (Sweden)

    Patrick Arbogast

    Full Text Available Thyroid hormone is a crucial regulator of gene expression in the developing and adult retina. Here we sought to map sites of thyroid hormone signaling at the cellular level using the transgenic FINDT3 reporter mouse model in which neurons express β-galactosidase (β-gal under the control of a hybrid Gal4-TRα receptor when triiodothyronine (T3 and cofactors of thyroid receptor signaling are present. In the adult retina, nearly all neurons of the ganglion cell layer (GCL, ganglion cells and displaced amacrine cells showed strong β-gal labeling. In the inner nuclear layer (INL, a minority of glycineric and GABAergic amacrine cells showed β-gal labeling, whereas the majority of amacrine cells were unlabeled. At the level of amacrine types, β-gal labeling was found in a large proportion of the glycinergic AII amacrines, but only in a small proportion of the cholinergic/GABAergic 'starburst' amacrines. At postnatal day 10, there also was a high density of strongly β-gal-labeled neurons in the GCL, but only few amacrine cells were labeled in the INL. There was no labeling of bipolar cells, horizontal cells and Müller glia cells at both stages. Most surprisingly, the photoreceptor somata in the outer nuclear layer also showed no β-gal label, although thyroid hormone is known to control cone opsin expression. This is the first record of thyroid hormone signaling in the inner retina of an adult mammal. We hypothesize that T3 levels in photoreceptors are below the detection threshold of the reporter system. The topographical distribution of β-gal-positive cells in the GCL follows the overall neuron distribution in that layer, with more T3-signaling cells in the ventral than the dorsal half-retina.

  15. The thyroid hormone receptors modulate the skin response to retinoids.

    Directory of Open Access Journals (Sweden)

    Laura García-Serrano

    Full Text Available Retinoids play an important role in skin homeostasis and when administered topically cause skin hyperplasia, abnormal epidermal differentiation and inflammation. Thyroidal status in humans also influences skin morphology and function and we have recently shown that the thyroid hormone receptors (TRs are required for a normal proliferative response to 12-O-tetradecanolyphorbol-13-acetate (TPA in mice.We have compared the epidermal response of mice lacking the thyroid hormone receptor binding isoforms TRα1 and TRβ to retinoids and TPA. Reduced hyperplasia and a decreased number of proliferating cells in the basal layer in response to 9-cis-RA and TPA were found in the epidermis of TR-deficient mice. Nuclear levels of proteins important for cell proliferation were altered, and expression of keratins 5 and 6 was also reduced, concomitantly with the decreased number of epidermal cell layers. In control mice the retinoid (but not TPA induced parakeratosis and diminished expression of keratin 10 and loricrin, markers of early and terminal epidermal differentiation, respectively. This reduction was more accentuated in the TR deficient animals, whereas they did not present parakeratosis. Therefore, TRs modulate both the proliferative response to retinoids and their inhibitory effects on skin differentiation. Reduced proliferation, which was reversed upon thyroxine treatment, was also found in hypothyroid mice, demonstrating that thyroid hormone binding to TRs is required for the normal response to retinoids. In addition, the mRNA levels of the pro-inflammatory cytokines TNFα and IL-6 and the chemotactic proteins S1008A and S1008B were significantly elevated in the skin of TR knock-out mice after TPA or 9-cis-RA treatment and immune cell infiltration was also enhanced.Since retinoids are commonly used for the treatment of skin disorders, these results demonstrating that TRs regulate skin proliferation, differentiation and inflammation in response to

  16. The thyroid and the thyroid hormones (in Romanian

    Directory of Open Access Journals (Sweden)

    Andreea Pap,

    2014-12-01

    Full Text Available The thyroid gland is located in the cervical fascia were it is divided in two lateral lobes, right and left, disposed on both sides of the trachea, and unlike other vertebrates, the cat does not have an isthmus that connects the two lobes. The main products of secretion of the thyroid gland are represented by thyroxine [T4] and 3,5,3 'triiodothyronine [T3]. To these are added other hormones resulted from the deiodination of the principle hormones. This process is catalized by the D1, D2 and D3 deiodinase resulting 3,3,5' triiodothyronine [rT3], 3,5-T2, 3,3’-T2 or 3’,5’-T2 which by further deiodination will form 3-3'-T1 and T1. To reach this deiodination must be followed certain steps in the hormon synthesis transport path, and it is important the present of the carrier protein. Once inside the tissue, the concentration of each hormone will vary depending on the binding site and the metabolic processes that will be followed.

  17. Neurodevelopment and Thyroid Hormone Synthesis Inhibition in the Rat: Quantitative Understanding Within the Adverse Outcome Pathway Framework

    Science.gov (United States)

    Adequate levels of thyroid hormones (TH) are needed for proper brain development, deficiencies may lead to adverse neurological outcomes in humans and animal models. Environmental chemicals have been linked to TH disruption, yet the relationship between developmental exposures an...

  18. Mild Thyroid Hormone Insufficiency During Development Compromises Activity-Dependent Neuroplasticity in the Hippocampus of Adult Make Rats

    Science.gov (United States)

    Severe thyroid hormone (TH) deficiency during critical phases of brain development results in irreversible neurological and cognitive impairments. The mechanisms accounting for this are likely multifactorial, and are not fully understood. Here we pursue the possibility that one i...

  19. Genetics Home Reference: isolated growth hormone deficiency

    Science.gov (United States)

    ... cells that help protect the body against infection (agammaglobulinemia). Related Information What does it mean if a ... deficiency type 1B Genetic Testing Registry: X-linked agammaglobulinemia with growth hormone deficiency Other Diagnosis and Management ...

  20. Thyroid hormone receptor β mediates acute illness-induced alterations in central thyroid hormone metabolism.

    Science.gov (United States)

    Boelen, A; Kwakkel, J; Chassande, O; Fliers, E

    2009-05-01

    Acute illness in mice profoundly affects thyroid hormone metabolism in the hypothalamus and pituitary gland. It remains unknown whether the thyroid hormone receptor (TR)-β is involved in these changes. In the present study, we investigated central thyroid hormone metabolism during lipopolysaccharide (LPS)-induced illness in TRβ(-/-) mice compared to wild-type (WT) mice. We administered a sublethal dose of LPS or saline to TRβ(-/-) and WT mice. TRβ(-/-) mice displayed higher basal levels of serum triiodothyronine (T(3)) and thyroxine (T(4)) compared to WT, reflecting thyroid hormone resistance. In the periventricular area of the hypothalamus, we observed a marked decrease in thyrotrophin-releasing hormone (TRH) mRNA expression in TRβ(-/-) and WT mice at t = 4 h, coinciding with the peak in plasma corticosterone. The decrease in TRH mRNA persisted in WT, but not in TRβ(-/-) mice at t = 24 h. By contrast, the increase of type 2 deiodinase (D2) mRNA already present at 4 h after LPS remained significant at 24 h in TRβ(-/-), but not in WT mice. LPS decreased pituitary thyroid-stimulating hormone β mRNA expression in WT at 24 h but not in TRβ(-/-) mice. The peak in pituitary D2 expression at t = 4 h in WT was absent in TRβ(-/-) mice. The relative decrease in plasma T(3) and T(4) upon LPS treatment was similar in both strains, although, at t = 24 h, plasma T(3) tended to be restored in TRβ(-/-) mice. Our results suggest that TRβ is involved in suppression of the central component of the hypothalamic-pituitary-thyroid axis in acute illness.

  1. New Approaches to Thyroid Hormones and Purinergic Signaling

    OpenAIRE

    Silveira, Gabriel Fernandes; Buffon, Andréia; Bruno, Alessandra Nejar

    2013-01-01

    It is known that thyroid hormones influence a wide variety of events at the molecular, cellular, and functional levels. Thyroid hormones (TH) play pivotal roles in growth, cell proliferation, differentiation, apoptosis, development, and metabolic homeostasis via thyroid hormone receptors (TRs) by controlling the expression of TR target genes. Most of these effects result in pathological and physiological events and are already well described in the literature. Even so, many recent studies hav...

  2. Paracrine Interactions of Thyroid Hormones and Thyroid Stimulation Hormone in the Female Reproductive Tract have an Impact on Female Fertility

    OpenAIRE

    Stavreus Evers, Anneli

    2012-01-01

    Thyroid disease often causes menstrual disturbances and infertility problems. Thyroid hormone (TH) acts through its receptors, transcription factors present in most cell types in the body. Thyroid stimulating hormone (TSH) stimulates TH synthesis in the thyroid gland, but seems to have other functions as well in the female reproductive tract. The receptors of both TH and TSH increase in the receptive endometrium, suggesting that they are important for implantation, possible by influencing inf...

  3. The chicken c-erbA alpha-product induces expression of thyroid hormone-responsive genes in 3,5,3'-triiodothyronine receptor-deficient rat hepatoma cells

    DEFF Research Database (Denmark)

    Muñoz, A; Höppner, W; Sap, J

    1990-01-01

    nuclear expression of the cTR-alpha protein the cells become responsive to thyroid hormone, as detected by expression of a number of genes (malic enzyme, phosphoenolpyruvate carboxykinase, and Na+/K(+)-ATPase) reported to be indirectly induced by the hormone in vivo. In addition, our data show that the c...

  4. Thyroid Hormones, Oxidative Stress, and Inflammation

    Directory of Open Access Journals (Sweden)

    Antonio Mancini

    2016-01-01

    Full Text Available Inflammation and oxidative stress (OS are closely related processes, as well exemplified in obesity and cardiovascular diseases. OS is also related to hormonal derangement in a reciprocal way. Among the various hormonal influences that operate on the antioxidant balance, thyroid hormones play particularly important roles, since both hyperthyroidism and hypothyroidism have been shown to be associated with OS in animals and humans. In this context, the nonthyroidal illness syndrome (NTIS that typically manifests as reduced conversion of thyroxine (T4 to triiodothyronine (T3 in different acute and chronic systemic conditions is still a debated topic. The pathophysiological mechanisms of this syndrome are reviewed, together with the roles of deiodinases, the enzymes responsible for the conversion of T4 to T3, in both physiological and pathological situations. The presence of OS indexes in NTIS supports the hypothesis that it represents a condition of hypothyroidism at the tissue level and not only an adaptive mechanism to diseases.

  5. Transport of thyroid hormones via the choroid plexus into the brain: the roles of transthyretin and thyroid hormone transmembrane transporters

    OpenAIRE

    Richardson, Samantha J.; Wijayagunaratne, Roshen C.; D'Souza, Damian G.; Darras, Veerle M.; Van Herck, Stijn L. J.

    2015-01-01

    Thyroid hormones are key players in regulating brain development. Thus, transfer of appropriate quantities of thyroid hormones from the blood into the brain at specific stages of development is critical. The choroid plexus forms the blood-cerebrospinal fluid barrier. In reptiles, birds and mammals, the main protein synthesized and secreted by the choroid plexus is a thyroid hormone distributor protein: transthyretin. This transthyretin is secreted into the cerebrospinal fluid and moves thyroi...

  6. Thyroid hormone action on rat calvarial sutures.

    Science.gov (United States)

    Akita, S; Nakamura, T; Hirano, A; Fujii, T; Yamashita, S

    1994-01-01

    To clarify the effect of thyroid hormone on the calvarial sutures, the morphology, histology, and bone mineral density were analyzed in thyroid hormone-injected rats. A total of 80 female Wistar rats at the age of 10 days were divided into 2 groups; the triiodothyronine (T3)-treated rats (n = 40, T3 100 micrograms/kg body weight/day) were maintained under the same conditions as controls (n = 40, saline-vehicle only), and both were sacrificed at 50, 80, and 200 experimental days, respectively. T3-treated animals showed smaller values of lambda-asterion and pterion-bregma distances at the various periods of examination, resulting in smaller sizes in right-left direction of the skull. The sagittal suture distance in the skull specimens observed by Goldner's staining (fibrous tissue content) appeared smaller and the osseous margin widths greatly increased in the T3-treated rats. Fluorescent microscopy revealed that the tetracycline-calcein double labelings were not interrupted from the periosteal to the endosteal areas in any specimens indicating the scantiness of osteoclastic activity in the suture areas. Mineral apposition rates at the osseous edges of the suture were significantly increased in the T3-treated rats (p < 0.01 at the age of 90 days). The distance between the second labels and the distance between the first labels were significantly larger in the T3-treated rats. Bone mineral density (BMD) measurement showed that the T3 administration decreased only the calvarial BMD at the age of 210 days (p < 0.01), but did not decrease lumbar or femur BMD. This experiment demonstrated clear evidence of excess thyroid hormone action on the early narrowing of the sagittal suture in infantile hyperthyroid rats, probably due to the enhanced osteogenic activity caused by the hormone.

  7. Illness-induced changes in thyroid hormone metabolism: focus on the tissue level

    NARCIS (Netherlands)

    Kwakkel, J.; Fliers, E.; Boelen, A.

    2011-01-01

    During illness changes in thyroid hormone metabolism occur, collectively known as the non-thyroidal illness syndrome (NTIS). NTIS is characterised by low serum thyroid hormone levels without the expected rise in serum thyroid-stimulating hormone, indicating a major change in thyroid hormone feedback

  8. Dopamine-Responsive Growth-Hormone Deficiency and Central Hypothyroidism in Sepiapterin Reductase Deficiency.

    Science.gov (United States)

    Zielonka, Matthias; Makhseed, Nawal; Blau, Nenad; Bettendorf, Markus; Hoffmann, Georg Friedrich; Opladen, Thomas

    2015-01-01

    Sepiapterin reductase (SR) deficiency is a rare autosomal recessively inherited error of tetrahydrobiopterin (BH4) biosynthesis, resulting in disturbed dopaminergic and serotonergic neurotransmission. The clinical phenotype is characterized by dopa-responsive movement disorders including muscular hypotonia, dystonia, and parkinsonism. Due to the rarity of the disease, the phenotype of SR deficiency is far from being completely understood. Here, we report a 7-year-old boy, who was referred for diagnostic evaluation of combined psychomotor retardation, spastic tetraplegia, extrapyramidal symptoms, and short stature. Due to discrepancy between motor status and mental condition, analyses of biogenic amines and pterins in CSF were performed, leading to the diagnosis of SR deficiency. The diagnosis was confirmed by a novel homozygous mutation c.530G>C; p.(Arg177Pro) in exon 2 of the SPR gene. Because of persistent short stature, systematic endocrinological investigations were initiated. Insufficient growth-hormone release in a severe hypoglycemic episode after overnight fasting confirmed growth-hormone deficiency as a cause of short stature. In addition, central hypothyroidism was present. A general hypothalamic affection could be excluded. Since dopamine is known to regulate growth-hormone excretion, IGF-1, IGF-BP3, and peripheral thyroid hormone levels were monitored under L-dopa/carbidopa supplementation. Both growth-hormone-dependent factors and thyroid function normalized under treatment. This is the first report describing growth-hormone deficiency and central hypothyroidism in SR deficiency. It extends the phenotypic spectrum of the disease and identifies dopamine depletion as cause for the endocrinological disturbances.

  9. Transport of thyroid hormone in brain

    Directory of Open Access Journals (Sweden)

    Eva K Wirth

    2014-06-01

    Full Text Available Thyroid hormone (TH transport into the brain is not only pivotal for development and differentiation, but also for maintenance and regulation of adult central nervous system (CNS function. In this review, we highlight some key factors and structures regulating thyroid hormone uptake and distribution. Serum TH binding proteins play a major role for the availability of TH since only free hormone concentrations may dictate cellular uptake. One of these proteins, transthyretin is also present in the cerebrospinal fluid (CSF after being secreted by the choroid plexus. Entry routes into the brain like the blood-brain-barrier (BBB and the blood-CSF-barrier will be explicated regarding fetal and adult status. Recently identified TH transmembrane transporters (THTT like monocarboxylate transporter 8 (Mct8 play a major role in uptake of TH across the BBB but as well in transport between cells like astrocytes and neurons within the brain. Species differences in transporter expression will be presented and interference of TH transport by endogenous and exogenous compounds including endocrine disruptors and drugs will be discussed.

  10. Influence of thyroid hormones on biochemical parameters of liver ...

    African Journals Online (AJOL)

    Normal level of thyroid hormones is important for normal hepatic function and thyroid dysfunction may modulate metabolic function of liver. The purpose of this study is to determine whether liver function is associated with subclinical and overt hypothyroidism. Thyroid and liver function tests were evaluated in 47 patients with ...

  11. Suppression of Thyroid Hormone Receptor-Mediated Transcription ...

    African Journals Online (AJOL)

    We therefore examined the effect of methamidophos on thyroid hormone receptor (TR)-mediated gene expression using transient transfection-based reporter gene assay. Our results shows that methamidophos (10-6 M) suppressed thyroid hormone (TH)-induced TR-mediated transcription. We further examined the effects ...

  12. Maternal thyroid hormone trajectories during pregnancy and child behavioral problems

    NARCIS (Netherlands)

    Endendijk, Joyce|info:eu-repo/dai/nl/330190865; Wijnen, Hennie A.a.; Pop, Victor J.m.; van Baar, Anneloes|info:eu-repo/dai/nl/08504749X

    2017-01-01

    There is ample evidence demonstrating the importance of maternal thyroid hormones, assessed at single trimesters in pregnancy, for child cognition. Less is known, however, about the course of maternal thyroid hormone concentrations during pregnancy in relation to child behavioral development. Child

  13. Thyroid hormone resistance may course hypotonia in infancy

    DEFF Research Database (Denmark)

    Pivkovska, Julijana; Born, Alfred Peter; Nielsen, Claus Thøger

    2014-01-01

    Allan Herndon Dudley's syndrome (AHDS) is X-linked mental retardation and hypotonia caused by mutations in a thyroid hormone transporter gene - MCT8. The typical thyreoidea AHDS profile is elevated T3, low-normal T4 and normal or elevated thyroid stimulating hormone (TSH). Neonatal screening...

  14. Interactions of polyhalogenated aromatic hydrocarbons with thyroid hormone metabolism

    NARCIS (Netherlands)

    Schuur, A.G.

    1998-01-01

    This thesis deals with the possible interactions of polyhalogenated aromatic hydrocarbons and/or their metabolites with thyroid hormone metabolism. This chapter summarizes firstly the effects of thyroid hormone on the induction of biotransformation enzymes by PHAHs. Secondly, the results on

  15. Changes in thyroid hormone concentrations during neonatal extracorporeal membrane oxygenation

    NARCIS (Netherlands)

    Leeuwen, L. (L.); A.F.J. van Heijst (Arno); J.M. van Rosmalen (Joost); Y.B. de Rijke (Yolanda); L.W.J.E. Beurkens (Leonardus); D. Tibboel (Dick); E.L.T. van den Akker (Erica); H. IJsselstijn (Hanneke)

    2017-01-01

    textabstractObjective: Thyroid hormone concentrations can be disturbed during critical illness. Our aim was to determine changes in thyroid hormone concentrations during neonatal extracorporeal membrane oxygenation (ECMO). Study Design: We included 21 ECMO-treated neonates. Age-specific s.d. scores

  16. Thyroid hormones and adult-type Leydig cell development

    NARCIS (Netherlands)

    Rijntjes, E.

    2008-01-01

    Alterations in thyroid hormone levels are well known to influence key functions in growth and development. Although in many countries the diet is fortified with iodide, essential for thyroid hormone synthesis, still not all humans have access to fortified diets, leaving a substantial part of the

  17. Thyroid hormones profile in students of Makerere College of Health ...

    African Journals Online (AJOL)

    Serum concentrations of thyroxine (T4), triiodothyronine (T3) and Thyroid Stimulating Hormone (TSH) are used to assess thyroid function. It is recommended that each laboratory or hospital should establish its own reference values of T4, T3 and TSH for their clients because these hormones vary with ethnicity, geographical ...

  18. American Thyroid Association Guide to investigating thyroid hormone economy and action in rodent and cell models.

    Science.gov (United States)

    Bianco, Antonio C; Anderson, Grant; Forrest, Douglas; Galton, Valerie Anne; Gereben, Balázs; Kim, Brian W; Kopp, Peter A; Liao, Xiao Hui; Obregon, Maria Jesus; Peeters, Robin P; Refetoff, Samuel; Sharlin, David S; Simonides, Warner S; Weiss, Roy E; Williams, Graham R

    2014-01-01

    An in-depth understanding of the fundamental principles that regulate thyroid hormone homeostasis is critical for the development of new diagnostic and treatment approaches for patients with thyroid disease. Important clinical practices in use today for the treatment of patients with hypothyroidism, hyperthyroidism, or thyroid cancer are the result of laboratory discoveries made by scientists investigating the most basic aspects of thyroid structure and molecular biology. In this document, a panel of experts commissioned by the American Thyroid Association makes a series of recommendations related to the study of thyroid hormone economy and action. These recommendations are intended to promote standardization of study design, which should in turn increase the comparability and reproducibility of experimental findings. It is expected that adherence to these recommendations by investigators in the field will facilitate progress towards a better understanding of the thyroid gland and thyroid hormone dependent processes.

  19. American Thyroid Association Guide to Investigating Thyroid Hormone Economy and Action in Rodent and Cell Models

    Science.gov (United States)

    Anderson, Grant; Forrest, Douglas; Galton, Valerie Anne; Gereben, Balázs; Kim, Brian W.; Kopp, Peter A.; Liao, Xiao Hui; Obregon, Maria Jesus; Peeters, Robin P.; Refetoff, Samuel; Sharlin, David S.; Simonides, Warner S.; Weiss, Roy E.; Williams, Graham R.

    2014-01-01

    Background: An in-depth understanding of the fundamental principles that regulate thyroid hormone homeostasis is critical for the development of new diagnostic and treatment approaches for patients with thyroid disease. Summary: Important clinical practices in use today for the treatment of patients with hypothyroidism, hyperthyroidism, or thyroid cancer are the result of laboratory discoveries made by scientists investigating the most basic aspects of thyroid structure and molecular biology. In this document, a panel of experts commissioned by the American Thyroid Association makes a series of recommendations related to the study of thyroid hormone economy and action. These recommendations are intended to promote standardization of study design, which should in turn increase the comparability and reproducibility of experimental findings. Conclusions: It is expected that adherence to these recommendations by investigators in the field will facilitate progress towards a better understanding of the thyroid gland and thyroid hormone dependent processes. PMID:24001133

  20. Does thyroid gland examination by palpation alter serum hormone levels?

    Science.gov (United States)

    Toros, Sema Zer; Ozel, Leyla; Yekrek, Mehmet Murat; Toros, Ahmet Burak; Naiboglu, Baris; Kara, Melih; Erdoğdu, Erdal; Egeli, Erol; Titiz, Izzet

    2010-07-01

    The goal of this study was to investigate the effects of routine thyroid gland palpation on serum thyroid hormone levels. Prospective study at Haydarpaşa Numune Research and Education Hospital, Istanbul, Turkey. This study was carried out in two groups with a total of 50 consecutive adults. Group I consisted of 20 patients (12 female and 8 male, aged 20-48 years) with a diagnosis of nodular thyroid disease confirmed by ultrasound imaging techniques. The second group consisted of 30 otherwise healthy subjects (17 female and 13 male, aged 18-50 years) referred for neck and thyroid ultrasound and with no thyroid pathology detected. Thyroid gland palpations were performed by the same physician. Blood samples were obtained before and 2 hours after thyroid gland palpation. Serum total T3 (TT3), total T4 (TT4), free T3 (FT3), free T4 (FT4), thyroid stimulating hormone (TSH), and thyroglobulin (TG) measurements were made. We found that routine palpation in the first group caused a significant increase in serum TT3 (P .05). Preliminary data proposing a possible effect of routine thyroid gland palpation on serum thyroid hormone levels suggest that serum thyroid hormone measurements should be performed before any manipulation of the gland, including palpation, to avoid misdiagnosis.

  1. Thyroid hormone action: Astrocyte-neuron communication.

    Directory of Open Access Journals (Sweden)

    Beatriz eMorte

    2014-05-01

    Full Text Available Thyroid hormone action is exerted mainly through regulation of gene expression by binding of T3 to the nuclear receptors. T4 plays an important role as a source of intracellular T3 in the central nervous system via the action of the type 2 deiodinase, expressed in the astrocytes. A model of T3 availability to neural cells has been proposed and validated. The model contemplates that brain T3 has a double origin: a fraction is available directly from the circulation, and another is produced locally from T4 in the astrocytes by type 2 deiodinase. The fetal brain depends almost entirely on the T3 generated locally. The contribution of systemic T3 increases subsequently during development to account for approximately 50% of total brain T3 in the late postnatal and adult stages. In this article we review the experimental data in support of this model, and how the factors affecting T3 availability in the brain, such as deiodinases and transporters, play a decisive role in modulating local thyroid hormone action during development.

  2. Desethylamiodarone is a competitive inhibitor of the binding of thyroid hormone to the thyroid hormone alpha 1-receptor protein

    NARCIS (Netherlands)

    van Beeren, H. C.; Bakker, O.; Wiersinga, W. M.

    1995-01-01

    Desethylamiodarone (DEA), the major metabolite of the potent antiarrythmic drug amiodarone, is a non-competitive inhibitor of the binding of thyroid hormone (T3) to the beta 1-thyroid hormone receptor (T3R). In the present study, we investigated whether DEA acts in a similar way with respect to the

  3. Impaired hair growth and wound healing in mice lacking thyroid hormone receptors.

    Science.gov (United States)

    Contreras-Jurado, Constanza; García-Serrano, Laura; Martínez-Fernández, Mónica; Ruiz-Llorente, Lidia; Paramio, Jesus M; Aranda, Ana

    2014-01-01

    Both clinical and experimental observations show that the skin is affected by the thyroidal status. In hypothyroid patients the epidermis is thin and alopecia is common, indicating that thyroidal status might influence not only skin proliferation but also hair growth. We demonstrate here that the thyroid hormone receptors (TRs) mediate these effects of the thyroid hormones on the skin. Mice lacking TRα1 and TRβ (the main thyroid hormone binding isoforms) display impaired hair cycling associated to a decrease in follicular hair cell proliferation. This was also observed in hypothyroid mice, indicating the important role of the hormone-bound receptors in hair growth. In contrast, the individual deletion of either TRα1 or TRβ did not impair hair cycling, revealing an overlapping or compensatory role of the receptors in follicular cell proliferation. In support of the role of the receptors in hair growth, TRα1/TRβ-deficient mice developed alopecia after serial depilation. These mice also presented a wound-healing defect, with retarded re-epithelialization and wound gaping, associated to impaired keratinocyte proliferation. These results reinforce the idea that the thyroid hormone nuclear receptors play an important role on skin homeostasis and suggest that they could be targets for the treatment of cutaneous pathologies.

  4. Visualisation of thyroid hormone synthesis by ion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Audinot, J.N. [Department Science and Analysis of Materials (SAM), Centre de Recherche Public - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux (Luxembourg)], E-mail: audinot@lippmann.lu; Senou, M. [Laboratoire de Morphologie experimentale, Universite catholique de Louvain, Bruxelles (Belgium); Migeon, H.-N. [Department Science and Analysis of Materials (SAM), Centre de Recherche Public - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux (Luxembourg); Many, M.-C. [Laboratoire de Morphologie experimentale, Universite catholique de Louvain, Bruxelles (Belgium)

    2008-12-15

    The main function of the thyroid gland is to make hormones, T4 and T3, which are essential for the regulation of metabolic processes throughout the body. Caveolae harbour is the key enzymes involved in this iodide organification. The analyses of thyroids from normal mice and caveolin-1 Knockout mice (mice deficient in caveolin) have been performed using the SIMS imaging. In the thyroid of control mice, the epithelium is homogeneous and iodine ({sup 127}I) is observed in the follicle lumen. In Knockout mice, we observe an accumulation of intracellular vesicles and apoptotic nuclei resulting from oxidative stress due to H{sub 2}O{sub 2} overproduction also inducing apical lesions of the thyrocytes, at the site of iodine organification and H{sub 2}O{sub 2} generation. We also observe in the Knockout mice an accumulation of {sup 127}I in the cellular cytoplasm and an absence of the iodine in some follicular lumina, indicating a problem at the level of iodine organification.

  5. Central and peripheral effects of thyroid hormone signalling in the control of energy metabolism

    NARCIS (Netherlands)

    Alkemade, A.

    2010-01-01

    Increasing evidence points towards a role for thyroid hormone signalling in the central nervous system with respect to the development of symptoms of thyroid disease, in addition to the well-known peripheral effects of thyroid hormone. Thyroid hormone affects target tissues directly via thyroid

  6. Thyroid profiles in a patient with resistance to thyroid hormone and episodes of thyrotoxicosis, including repeated painless thyroiditis.

    Science.gov (United States)

    Taniyama, Matsuo; Otsuka, Fumiko; Tozaki, Teruaki; Ban, Yoshiyuki

    2013-07-01

    Thyrotoxic disease can be difficult to recognize in patients with resistance to thyroid hormone (RTH) because the clinical symptoms of thyrotoxicosis cannot be observed, and thyrotropin (TSH) may not be suppressed because of hormone resistance. Painless thyroiditis is a relatively common cause of thyrotoxicosis, but its occurrence in RTH has not been reported. We assessed the thyroid profile in a patient with RTH and episodes of thyrotoxicosis who experienced repeated painless thyroiditis. A 44-year-old Japanese woman with RTH, which was confirmed by the presence of a P453A mutation in the thyroid hormone receptor β (TRβ) gene, showed a slight elevation of the basal levels of thyroid hormones, which indicated that her pituitary RTH was mild. She experienced a slight exacerbation of hyperthyroxinemia concomitant with TSH suppression. A diagnosis of painless thyroiditis was made because of the absence of TSH receptor antibodies, low Tc-99m pertechnetate uptake by the thyroid gland, and transient suppression followed by a slight elevation of TSH following the elevation of thyroid hormones. The patient's complaints of general malaise and occasional palpitations did not change throughout the course of painless thyroiditis. Three years later, painless thyroiditis occurred again without any deterioration of the clinical manifestations. Mild pituitary RTH can be overcome by slight exacerbation of hyperthyroxinemia during mild thyrotoxicosis. When pituitary resistance is severe and TSH is not suppressed, thyrotoxicosis may be overlooked.

  7. The effects of thyroid hormone abnormalities on periodontal disease status.

    Science.gov (United States)

    Zahid, Talal M; Wang, Bing-Yan; Cohen, Robert E

    2011-10-01

    Thyroid hormones play an important role in the regulation of physiologic processes. Thyroid disease can lead to imbalance in the homeostasis of the body and affect the healing capacity of tissues. However, limited data are available regarding the relationship between thyroid hormone imbalance (thyroid disease) and periodontal health. This review is carried out to summarize the relationship between thyroid disease and periodontal status. PUBMED and MEDLINE searches of both human and animal studies were performed to investigate the relationship between thyroid disease, periodontal status, and dental implants. Results suggest that thyroid diseases may affect the status of periodontal diseases, especially in hypothyroid conditions. The duration from disease onset to treatment of thyroid disorders may be critical, since uncontrolled thyroid disease may result in destruction of the periodontium. Further controlled studies are needed to explore the relationship between thyroid hormone imbalance and periodontal status. Periodontal therapies, including dental implant placement, appear to be safe with no increase in treatment failure, so long as the status of the thyroid gland is controlled.

  8. Thyroid hormone and leptin in the testis

    Directory of Open Access Journals (Sweden)

    Cristiane Fonte Ramos

    2014-11-01

    Full Text Available Leptin is primarily expressed in white adipose tissue; however, it is expressed in the hypothalamus and reproductive tissues as well. Leptin acts by activating the leptin receptors (Ob-Rs. Additionally, the regulation of several neuroendocrine and reproductive functions, including the inhibition of glucocorticoids and enhancement of thyroxine and sex hormone concentrations in humans and mice are leptin functions. It has been suggested that thyroid hormones (TH could directly regulate leptin expression. Additionally, hypothyroidism compromises the intracellular integration of leptin signaling specifically in the arcuate nucleus. Two TH receptor isoforms are expressed in the testis, TRa and TRb, with TRa being the predominant one that is present in all stages of development. The effects of TH involve the proliferation and differentiation of Sertoli and Leydig cells during development, spermatogenesis and steroidogenesis. In this context, TH disorders are associated with sexual dysfunction. An endocrine and/or direct paracrine effect of leptin on the gonads inhibits testosterone production in Leydig cells. Further studies are necessary to clarify the effects of both hormones in the testis during hypothyroidism. The goal of this review is to highlight the current knowledge regarding leptin and TH in the testis.

  9. Genetics Home Reference: combined pituitary hormone deficiency

    Science.gov (United States)

    ... be associated with a deficiency of the hormone cortisol . Cortisol deficiency can impair the body's immune system, causing ... proteins called transcription factors, which help control the activity of many ... play a role in sexual development and the ability to have children (fertility); ...

  10. New Approaches to Thyroid Hormones and Purinergic Signaling

    Directory of Open Access Journals (Sweden)

    Gabriel Fernandes Silveira

    2013-01-01

    Full Text Available It is known that thyroid hormones influence a wide variety of events at the molecular, cellular, and functional levels. Thyroid hormones (TH play pivotal roles in growth, cell proliferation, differentiation, apoptosis, development, and metabolic homeostasis via thyroid hormone receptors (TRs by controlling the expression of TR target genes. Most of these effects result in pathological and physiological events and are already well described in the literature. Even so, many recent studies have been devoted to bringing new information on problems in controlling the synthesis and release of these hormones and to elucidating mechanisms of the action of these hormones unconventionally. The purinergic system was recently linked to thyroid diseases, including enzymes, receptors, and enzyme products related to neurotransmitter release, nociception, behavior, and other vascular systems. Thus, throughout this text we intend to relate the relationship between the TH in physiological and pathological situations with the purinergic signaling.

  11. [Cornelia de Lange Syndrome and multiple hormonal deficiency, an unusual association. Clinical case].

    Science.gov (United States)

    Mora-Bautista, Víctor M; Mendoza-Rojas, Víctor; Contreras-García, Gustavo A

    2017-06-01

    Cornelia de Lange syndrome is a genetic disease characterized by distinctive facial features, failure to thrive, microcephaly and several malformations associated. Its main endocrinological features are anomalies of the genitalia. We present a 13-year-old boy, who suffered from complicated aspiration pneumonia and showed Cornelia de Lange syndrome phenotype, with global developmental delay, suction-swallowing abnormalities, short stature and abnormal genitalia associated. His bone age was delayed, so he underwent full endocrinological panel. Central hypothyroidism, growth hormone deficiency and low luteinizing hormone-follicle-stimulating hormone levels were observed and multiple pituitary hormone deficiencies diagnosis was made. Basal cortisol, adrenocorticotropic hormone and prolactin levels were normal. He received thyroid hormonal substitution. Multiple pituitary hormone deficiencies are an unusual feature of De Lange syndrome. We suggest evaluating all different endocrine axes in these patients. Sociedad Argentina de Pediatría.

  12. Generalized resistance to thyroid hormone associated with a mutation in the ligand-binding domain of the human thyroid hormone receptor β

    International Nuclear Information System (INIS)

    Sakurai, A.; Takeda, K.; Ain, K.; Ceccarelli, P.; Nakai, A.; Seino, S.; Bell, G.I.; Refetoff, S.; DeGroot, L.J.

    1989-01-01

    The syndrome of generalized resistance to thyroid hormone is characterized by elevated circulating levels of thyroid hormone in the presence of an overall eumetabolic state and failure to respond normally to triiodothyronine. The authors have evaluated a family with inherited generalized resistance to thyroid hormone for abnormalities in the thyroid hormone nuclear receptors. A single guanine → cytosine replacement in the codon for amino acid 340 resulted in a glycine → arginine substitution in the hormone-binding domain of one of two alleles of the patient's thyroid hormone nuclear receptor β gene. In vitro translation products of this mutant human thyroid hormone nuclear receptor β gene did not bind triiodothyronine. Thus, generalized resistance to thyroid hormone can result from expression of an abnormal thyroid hormone nuclear receptor molecule

  13. Synthesis of Analogues of Thyroid Hormones: Nuclear Receptor Modulators

    Directory of Open Access Journals (Sweden)

    Guilherme Vieira de Castro

    2015-09-01

    Full Text Available Thyroid hormones are essential for the development and differentiation of all cells of the human body. This work reports the synthesis of some synthetic structural analogues of thyroid hormones, which may be modulators of the thyroid hormone receptor. The known compounds GC-1 (Sobetirome and CG-24 were successfully prepared and two novel analogous molecules were also synthesized by a new and efficient synthetic methodology. DOI: http://dx.doi.org/10.17807/orbital.v7i3.739  

  14. Receptors for thyrotropin-releasing hormone, thyroid-stimulating hormone, and thyroid hormones in the macaque uterus: effects of long-term sex hormone treatment.

    Science.gov (United States)

    Hulchiy, Mariana; Zhang, Hua; Cline, J Mark; Hirschberg, Angelica Lindén; Sahlin, Lena

    2012-11-01

    Thyroid gland dysfunction is associated with menstrual cycle disturbances, infertility, and increased risk of miscarriage, but the mechanisms are poorly understood. However, little is known about the regulation of these receptors in the uterus. The aim of this study was to determine the effects of long-term treatment with steroid hormones on the expression, distribution, and regulation of the receptors for thyrotropin-releasing hormone (TRHR) and thyroid-stimulating hormone (TSHR), thyroid hormone receptor α1/α2 (THRα1/α2), and THRβ1 in the uterus of surgically menopausal monkeys. Eighty-eight cynomolgus macaques were ovariectomized and treated orally with conjugated equine estrogens (CEE; n = 20), a combination of CEE and medroxyprogesterone acetate (MPA; n = 20), or tibolone (n = 28) for 2 years. The control group (OvxC; n = 20) received no treatment. Immunohistochemistry was used to evaluate the protein expression and distribution of the receptors in luminal epithelium, glands, stroma, and myometrium of the uterus. Immunostaining of TRHR, TSHR, and THRs was detected in all uterine compartments. Epithelial immunostaining of TRHR was down-regulated in the CEE + MPA group, whereas in stroma, both TRHR and TSHR were increased by CEE + MPA treatment as compared with OvxC. TRHR immunoreactivity was up-regulated, but THRα and THRβ were down-regulated, in the myometrium of the CEE and CEE + MPA groups. The thyroid-stimulating hormone level was higher in the CEE and tibolone groups as compared with OvxC, but the level of free thyroxin did not differ between groups. All receptors involved in thyroid hormone function are expressed in monkey uterus, and they are all regulated by long-term steroid hormone treatment. These findings suggest that there is a possibility of direct actions of thyroid hormones, thyroid-stimulating hormone and thyrotropin-releasing hormone on uterine function.

  15. Growth Hormone Deficiency in Adults

    Science.gov (United States)

    ... in your body Increase exercise capacity Build stronger bones: Growth hormone spurs bone formation and bone resorption (the breakdown of old ... should have a DXA bone scan to measure bone density before treatment with growth hormone. If it is abnormal, a DXA should be ...

  16. Role and Mechanisms of Actions of Thyroid Hormone on the Skeletal Development

    OpenAIRE

    Kim, Ha-Young; Mohan, Subburaman

    2013-01-01

    The importance of the thyroid hormone axis in the regulation of skeletal growth and maintenance has been well established from clinical studies involving patients with mutations in proteins that regulate synthesis and/or actions of thyroid hormone. Data from genetic mouse models involving disruption and overexpression of components of the thyroid hormone axis also provide direct support for a key role for thyroid hormone in the regulation of bone metabolism. Thyroid hormone regulates prolifer...

  17. Hyponatremia after Thyroid Hormone Withdrawal in a Patient with Papillary Thyroid Carcinoma

    Directory of Open Access Journals (Sweden)

    Hyo Jin Jo

    2014-03-01

    Full Text Available Hyponatremia is an electrolyte abnormality commonly found in clinical practice. It is important to diagnose the underlying etiology of the hyponatremia and correct it appropriately because severe hyponatremia can cause serious complications and substantially increase the risk of mortality. Although hypothyroidism is known to be a cause of hyponatremia, it is rare that hyponatremia occurs in relation to hypothyroidism induced by thyroid hormone withdrawal in patients with differentiated thyroid cancer. We report a case of a 76-year-old woman with papillary thyroid carcinoma presenting with severe hyponatremia related to hypothyroidism induced by thyroid hormone withdrawal for radio-active iodine whole-body scanning, who was treated by thyroid hormone replacement and hydration. Considering that the incidence of differentiated thyroid cancer is rapidly increasing, physicians should be aware that, although uncommon, hyponatremia can occur in patients undergoing radioiodine therapy or diagnostic testing.

  18. Effects of long-term nadolol treatment on serum thyroidal hormones and thyroid stimulating hormone in patients with hypertensive disease

    International Nuclear Information System (INIS)

    Gumbatov, N.B.; Mustafaev, I.I.; Kasumova, F.Z.; Mamedova, R.N.; Akhmedova, Z.G.; Samojlenko, T.I.

    1990-01-01

    In 20 males with Stage 2 hypertensive disease, effects of 2-week-, 2-, and 6-month monotherapy with nadolol given in doses 40 to 160 mg daily were examined on the levels of thyroidal hormones (T 3 and T 4 ) and thyroid-stimulating hormone by means of radioimmunoassay. At the all stages of the therapy, the mean values of the examined parameters were significantly unchanged. Nadolol was found to cause a decrease in T 3 concentrations at its high baseline values (r=-0.57; p 3 levels in most cases. An inverse relationship was established between the altered serum T 3 levels and the thyroid-stimulating hormone concentration

  19. Novel neural pathways for metabolic effects of thyroid hormone

    NARCIS (Netherlands)

    Fliers, Eric; Klieverik, Lars P.; Kalsbeek, Andries

    2010-01-01

    The relation between thyrotoxicosis, the clinical syndrome resulting from exposure to excessive thyroid hormone concentrations, and the sympathetic nervous system remains enigmatic. Nevertheless, beta-adrenergic blockers are widely used to manage severe thyrotoxicosis. Recent experiments show that

  20. Thyroid hormone effect on human mitochondria measured by flow cytometry

    DEFF Research Database (Denmark)

    Kvetny, Jan; Bomholt, Tobias; Pedersen, Palle

    2009-01-01

    a method to measure mitochondrial function in human derived cells, which also would reflect regulation by thyroid hormones. METHODS: The MDA-MB-231 cell line (a human breast cancer cell line) was incubated with bioactive iodothyronines (T(4), 3'-3, 5-T(3), 3, 5-T(2)) 50 nmol/l for 3 h. Mitochondrial...... membrane potentials (MMP) were measured by a flow cytometer after staining with Tetramethylrhodamine methyl ester (TMRM). Also, the effect of TRIAC (a stimulator of thyroid hormone nuclear receptors) and L-Carnitine (an inhibitor of thyroid hormone passage into the nucleus) was examined. FINDINGS......: It was possible to measure mitochondrial membrane potential (MMP) in human derived cells and to examine thyroid hormone effects using flow cytometry. Bioactive iodothyronines increased mitochondrial membrane potential. TRIAC had no effect and L-Carnitine only inhibited T(4) stimulation of membrane potential...

  1. Methodologic and clinical aspects of free thyroid hormone assay

    International Nuclear Information System (INIS)

    Hermans, J.; Baldewyns, P.; Beauduin, M.

    1984-01-01

    The diagnostic value of free thyroid hormones measures depends on used technic. The results gived by two different kits are compared: - Kit Le Petit with chromatographic separation, - Kit Amersham which uses an analogue [fr

  2. Molecular Basis for Certain Neuroprotective Effects of Thyroid Hormone

    Directory of Open Access Journals (Sweden)

    Paul eDavis

    2011-10-01

    Full Text Available The pathophysiology of brain damage that is common to ischemia-reperfusion inury and brain trauma includes disordered neuronal and glial cell energetics, intracellular acidosis, calcium toxicity, extracellular excitotoxic glutamate accumulation and dysfunction of the cytoskeleton and endoplasmic reticulum. Thyroid hormone isoforms, 3, 5, 3'-triiodo-L-thyronine (T3 and L-thyroxine (T4, have nongenomic and genomic actions that are relevant to repair of certain features of the pathophysiology of brain damage. Thyroid hormone can nongenomically repair intracullar H+ accumulation by stimulation of the Na+/H+ exchanger and can support desirably low [Ca2+]i.c. by activation of plasma membrane Ca2+-ATPase. Thyroid hormone nongenomically stimulates astrocyte glutamate uptake, an action that protects both glial cells and neurons. The hormone supports the integrity of the cytoskeleton by its effect on actin. Several proteins linked to thyroid hormone action are also neuroprotective. For example, the hormone stimulates expression of the seladin-1 gene whose gene product is anti-apoptotic and is potentially protection in the setting of neurodegeneration. Transthyretin (TTR is a serum transport protein for T4 that is important to blood-brain barrier transfer of the hormone and TTR has also been found to be neuroprotective in the setting of ischemia. Finally, the interesting thyronamine derivatives of T4 have been shown to protect against ischemic brain damage through their ability to induce hypothermia in the intact organism. Thus, thyroid hromone or hormone derivatives have experimental promise as neuroprotective agents.

  3. Revisiting available knowledge on teleostean thyroid hormone receptors.

    Science.gov (United States)

    Lazcano, Iván; Orozco, Aurea

    2018-03-21

    Teleosts are the most numerous class of living vertebrates. They exhibit great diversity in terms of morphology, developmental strategies, ecology and adaptation. In spite of this diversity, teleosts conserve similarities at molecular, cellular and endocrine levels. In the context of thyroidal systems, and as in the rest of vertebrates, thyroid hormones in fish regulate development, growth and metabolism by actively entering the nucleus and interacting with thyroid hormone receptors, the final sensors of this endocrine signal, to regulate gene expression. In general terms, vertebrates express the functional thyroid hormone receptors alpha and beta, encoded by two distinct genes (thra and thrb, respectively). However, different species of teleosts express thyroid hormone receptor isoforms with particular structural characteristics that confer singular functional traits to these receptors. For example, teleosts contain two thra genes and in some species also two thrb; some of the expressed isoforms can bind alternative ligands. Also, some identified isoforms contain deletions or large insertions that have not been described in other vertebrates and that have not yet been functionally characterized. As in amphibians, the regulation of some of these teleost isoforms coincides with the climax of metamorphosis and/or life transitions during development and growth. In this review, we aimed to gain further insights into thyroid signaling from a comparative perspective by proposing a systematic nomenclature for teleost thyroid hormone receptor isoforms and summarize their particular functional features when the information was available. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Paracrine interactions of thyroid hormones and thyroid stimulation hormone in the female reproductive tract have an impact on female fertility

    Directory of Open Access Journals (Sweden)

    Anneli eStavreus-Evers

    2012-03-01

    Full Text Available Thyroid disease often causes menstrual disturbances and infertility problems. Thyroid hormone (TH acts through its receptors, transcription factors present in most cell types in the body. Thyroid stimulating hormone (TSH stimulates TH synthesis in the thyroid gland, but seems to have other functions as well in the female reproductive tract. The receptors of both TH and TSH increase in the receptive endometrium, suggesting that they are important for implantation, possible by influencing inflammatory mediators such as LIF. The roles of these receptors in the ovary need further studies. However, it is likely that the thyroid system is important for both follicular and embryo development. The association between thyroid disease and infertility indicate that TH and TSH affect the endometrium and ovary on the paracrine level.

  5. Thyroid Hormone-Dependent Formation of a Subcortical Band Heterotopia (SBH) in the Neonatal Brain is not Exacerbated Under Conditions of Low Dietary Iron (FeD)

    Science.gov (United States)

    Although the critical role of thyroid hormone (TH) in brain development is well established - severe deficiency producing significant neurological dysfunction - there is a paucity of data on neurological impairments that accompany modest degrees of TH disruption. Quantitative m...

  6. The interaction between growth hormone and the thyroid axis in hypopituitary patients.

    LENUS (Irish Health Repository)

    Behan, Lucy Ann

    2012-02-01

    Alterations in the hypothalamo-pituitary-thyroid axis have been reported following growth hormone (GH) administration in both adults and children with and without growth hormone deficiency. Reductions in serum free thyroxine (T4), increased tri-iodothyronine (T3) with or without a reduction in serum thyroid-stimulating hormone secretion have been reported following GH replacement, but there are wide inconsistencies in the literature about these perturbations. The clinical significance of these changes in thyroid function remains uncertain. Some authors report the changes are transient and revert to normal after a few months or longer. However, in adult hypopituitary patients, GH replacement has been reported to unmask central hypothyroidism biochemically in 36-47% of apparently euthyroid patients, necessitating thyroxine replacement and resulting in an attenuation of the benefit of GH replacement on quality of life in those who became biochemically hypothyroid after GH replacement. The group at highest risk are those with organic pituitary disease or multiple pituitary hormone deficiencies. It is therefore prudent to monitor thyroid function in hypopituitary patients starting GH therapy to identify those who will develop clinical and biochemical features of central hypothyroidism, thus facilitating optimal and timely replacement.

  7. The interaction between growth hormone and the thyroid axis in hypopituitary patients.

    LENUS (Irish Health Repository)

    Behan, Lucy Ann

    2011-03-01

    Alterations in the hypothalamo-pituitary-thyroid axis have been reported following growth hormone (GH) administration in both adults and children with and without growth hormone deficiency. Reductions in serum free thyroxine (T4), increased tri-iodothyronine (T3) with or without a reduction in serum thyroid-stimulating hormone secretion have been reported following GH replacement, but there are wide inconsistencies in the literature about these perturbations. The clinical significance of these changes in thyroid function remains uncertain. Some authors report the changes are transient and revert to normal after a few months or longer. However, in adult hypopituitary patients, GH replacement has been reported to unmask central hypothyroidism biochemically in 36-47% of apparently euthyroid patients, necessitating thyroxine replacement and resulting in an attenuation of the benefit of GH replacement on quality of life in those who became biochemically hypothyroid after GH replacement. The group at highest risk are those with organic pituitary disease or multiple pituitary hormone deficiencies. It is therefore prudent to monitor thyroid function in hypopituitary patients starting GH therapy to identify those who will develop clinical and biochemical features of central hypothyroidism, thus facilitating optimal and timely replacement.

  8. Deiodinases: the balance of thyroid hormone: type 1 iodothyronine deiodinase in human physiology and disease.

    Science.gov (United States)

    Maia, Ana Luiza; Goemann, Iuri Martin; Meyer, Erika L Souza; Wajner, Simone Magagnin

    2011-06-01

    Thyroid hormone is essential for the normal function of virtually all tissues. The iodothyronine deiodinases catalyze the removal of an iodine residue from the pro-hormone thyroxine (T(4)) molecule, thus producing either the active form triiodothyronine (T(3); activation) or inactive metabolites (reverse T(3); inactivation). Type I deiodinase (D1) catalyzes both reactions. Over the last years, several studies have attempted to understand the mechanisms of D1 function, underlying its effects on normal thyroid hormone metabolism and pathological processes. Although peripheral D1-generated T(3) production contributes to a portion of plasma T(3) in euthyroid state, pathologically increased thyroidal D1 activity seems to be the main cause of the elevated T(3) concentrations observed in hyperthyroid patients. On the other hand, D1-deficient mouse models show that, in the absence of D1, inactive and lesser iodothyronines are excreted in feces with the loss of associated iodine, demonstrating the scavenging function for D1 that might be particularly important in an iodine deficiency setting. Polymorphisms in the DIO1 gene have been associated with changes in serum thyroid hormone levels, whereas decreased D1 activity has been reported in the nonthyroid illness syndrome and in several human neoplasias. The current review aims at presenting an updated picture of the recent advances made in the biochemical and molecular properties of D1 as well as its role in human physiology.

  9. Thyroid hormones and iodide in the near-term pregnant rat

    NARCIS (Netherlands)

    Versloot, P.

    1998-01-01

    Thyroid hormones, thyroxine (T4) and 3,5,3'-triiodothyronine (T3), are produced by the thyroid gland. To synthesize thyroid hormones the thyroid needs iodide. The uptake of iodide as well as the production and secretion of T4 and T3 by the thyroid gland is regulated by thyrotropin (TSH),

  10. Comparison level of thyroid and thyroid related hormones between sudanese males and females

    International Nuclear Information System (INIS)

    Madani, H.; Hassan, AME.; Basama, N. K.; Mohamed, W.A.S.; Eltayeb, N. H.; Elsayed, B. B.

    2012-12-01

    The function of the thyroid gland is under the control of pituitary gland through the thyroid stimulating hormone (TSH). It secretes the thyroid hormones tetra-iodo-thyronine (T 4 ) and Tri-iodo-thyronine (T 3 ). More secretion of thyroid hormones (hyperthyroidism) and low secretion (hypothyroidism) sometimes happen. This study was carried out to determine thyroid disorders in patients referred to radioimmunoassay (RIA) laboratory of Sudan Atomic Energy Commission (SAEC) during 2006-2010 for the thyroid function test. Disorders were detected using radioimmunoassay and Immuno radiometric assay. The total number of patients referred during these years were found to be 4700 sudanese patients, among them 4165 were females representing 88.6% compared to 535 males representing 11.4%. The total concentration of thyroid hormones thyroxine (T 4 ), tri iodine thyronine (T 3 ) and thyroid simulating stimulating hormones (TSH) were d terminated the prevalence of euthyroid was (66.5%), hypothyroidism was (11.8%) and of hyperthyroidism was (21.7%). These percentages did not vary significantly with sex. (Author)

  11. The thyroid gland and thyroid hormones in sheepshead minnow (Cyprinodon variegatus) during early development and metamorphosis.

    Science.gov (United States)

    Schnitzler, Joseph G; Klaren, Peter H M; Mariavelle, Emeline; Das, Krishna

    2016-04-01

    The sheepshead minnow is widely used in ecotoxicological studies that only recently have begun to focus on disruption of the thyroid axis by xenobiotics and endocrine disrupting compounds. However, reference levels of the thyroid prohormone thyroxine (T4) and biologically active hormone 3,5,3'-triiodothyronine (T3) and their developmental patterns are unknown. This study set out to describe the ontogeny and morphology of the thyroid gland in sheepshead minnow, and to correlate these with whole-body concentrations of thyroid hormones during early development and metamorphosis. Eggs were collected by natural spawning in our laboratory. T4 and T3 were extracted from embryos, larvae and juveniles and an enzyme-linked immunoassay was used to measure whole-body hormone levels. Length and body mass, hatching success, gross morphology, thyroid hormone levels and histology were measured. The onset of metamorphosis at 12-day post-hatching coincided with surges in whole-body T4 and T3 concentrations. Thyroid follicles were first observed in pre-metamorphic larvae at hatching and were detected exclusively in the subpharyngeal region, surrounding the ventral aorta. Follicle size and thyrocyte epithelial cell heights varied during development, indicating fluctuations in thyroid hormone synthesis activity. The increase in the whole-body T3/T4 ratio was indicative of an increase in outer ring deiodination activity. This study establishes a baseline for thyroid hormones in sheepshead minnows, which will be useful for the understanding of thyroid hormone functions and in future studies of thyroid toxicants in this species.

  12. Pathophysiological aspects of thyroid hormone disorders/thyroid peroxidase autoantibodies and reproduction

    NARCIS (Netherlands)

    Vissenberg, R.; Manders, V. D.; Mastenbroek, S.; Fliers, E.; Afink, G. B.; Ris-Stalpers, C.; Goddijn, M.; Bisschop, P. H.

    2015-01-01

    Thyroid hormone disorders and thyroid peroxidase autoantibodies (TPO-Ab) in women are associated with subfertility and early pregnancy loss. Here, we aim to provide a comprehensive overview of the literature on the pathophysiology of these associations. A review of the literature in the English

  13. Endocrine determinants of haemostasis and thrombosis risk: Focus on thyroid hormone

    NARCIS (Netherlands)

    Elbers, L.P.B.

    2016-01-01

    This thesis explores endocrine determinants of the haemostatic system and thrombosis risk with main focus on thyroid hormone. It describes, in three parts, the effects of thyroid hormone on the haemostatic system, the effects of thyroid hormone (mimetics) on lipids and the effects of other hormones

  14. Thyroid Diseases

    Science.gov (United States)

    ... your thyroid gland does not make enough thyroid hormones Thyroid cancer Thyroid nodules - lumps in the thyroid gland Thyroiditis - swelling of the thyroid To diagnose thyroid diseases, doctors use a medical history, physical exam, and thyroid tests. They sometimes also ...

  15. Primary and secondary thyroid hormone transporters

    Directory of Open Access Journals (Sweden)

    Kinne Anita

    2011-08-01

    Full Text Available Abstract Thyroid hormones (TH are essential for the development of the human brain, growth and cellular metabolism. Investigation of TH transporters became one of the emerging fields in thyroid research after the discovery of inactivating mutations in the Monocarboxylate transporter 8 (MCT8, which was found to be highly specific for TH transport. However, additional transmembrane transporters are also very important for TH uptake and efflux in different cell types. They transport TH as secondary substrates and include the aromatic amino acid transporting MCT10, the organic anion transporting polypeptides (e.g. OATP1C1, OATP1A2, OPTP1A4 and the large neutral amino acid transporters (LAT1 and LAT2. These TH transporters characteristically possess 12 transmembrane spanners but due to the strong differing sequences between the three transporter families we assume an identical conformation is not very likely. In contrast to the others, the LAT family members form a heterodimer with the escort protein 4F2hc/CD98. A comparison of sequence proportions, locations and types of functional sensitive features for TH transport discovered by mutations, revealed that transport sensitive charged residues occur as conserved amino acids only within each family of the transporter types but not in all putative TH transporters. Based on the lack of highly conserved sensitive charged residues throughout the three transporter families as a common counterpart for the amino acid moiety of the substrates, we conclude that the molecular transport mechanism is likely organized either a by different molecular determinants in the divergent transporter types or b the counterparts for the substrates` amino acid moiety at the transporter are not any charged side chains but other proton acceptors or donators. However, positions of transport sensitive residues coincide at transmembrane helix 8 in the TH transporter MCT8, OATP1C1 and another amino acid transporter, the L

  16. Trends in thyroid hormone prescribing and consumption in the UK

    Directory of Open Access Journals (Sweden)

    Hickey Janis L

    2009-05-01

    Full Text Available Abstract Background Thyroid hormone replacement is one of the most commonly prescribed and cost effective treatments for a chronic disease. There have been recent changes in community prescribing policies in many areas of the UK that have changed patient access to necessary medications. This study aimed to provide a picture of thyroid hormone usage in the UK and to survey patient opinion about current community prescribing policies for levothyroxine. Methods Data on community prescriptions for thyroid hormones in England between 1998 and 2007, provided by the Department of Health, were collated and analysed. A survey of UK members of a patient support organisation (the British Thyroid Foundation who were taking levothyroxine was carried out. Results The amount of prescribed thyroid hormones used in England has more than doubled, from 7 to almost 19 million prescriptions, over the last 10 years. The duration of prescriptions has reduced from 60 to 45 days, on average over the same time. Two thousand five hundred and fifty one responses to the patient survey were received. Thirty eight percent of levothyroxine users reported receiving prescriptions of 28 days' duration. 59% of respondents reported being dissatisfied with 28-day prescribing. Conclusion Amongst users of levothyroxine, there is widespread patient dissatisfaction with 28-day prescription duration. Analysis of the full costs of 28-day dispensing balanced against the potential savings of reduced wastage of thyroid medications, suggests that this is unlikely to be an economically effective public health policy.

  17. Tissue specific regulation of lipogenesis by thyroid hormone

    Energy Technology Data Exchange (ETDEWEB)

    Blennemann, B.; Freake, H. (Univ. of Connecticut, Storrs (United States))

    1990-02-26

    Thyroid hormone stimulates long chain fatty acid synthesis in rat liver by increasing the amounts of key lipogenic enzymes. Sparse and conflicting data exist concerning its action on this pathway in other tissues. The authors recently showed that, in contrast to liver, hypothyroidism stimulates lipogenesis in brown adipose tissue and have now systematically examined the effects of thyroid state on fatty acid synthesis in other rat tissues. Lipogenesis was assessed by tritiated water incorporation. Euthyroid hepatic fatty acid synthesis (16.6um H/g/h) was reduced to 30% in hypothyroid rats and increased 3 fold in hyperthyroidism. Lipogenesis was detected in euthyroid kidney and heart and these levels were also stimulated by thyroid hormone treatment. Brown adipose tissue was unique in showing increased lipogenesis in the hypothyroid state. Hyperthyroid levels were not different from euthyroid. Effects in white adipose tissue were small and inconsistent. Brain, skin and lung were all lipogenically active, but did not respond to changes in thyroid state. Low but detectable levels of fatty acid synthesis were measured in muscle, which also were non-responsive. A wide spectrum of responses to thyroid hormone are seen in different rat tissues and thus the pathway of long chain fatty acid synthesis would appear to be an excellent model for examining the tissue specific regulation of gene expression by thyroid hormone.

  18. Doubling in the use of thyroid hormone replacement therapy in Denmark: association to iodization of salt?

    DEFF Research Database (Denmark)

    Cerqueira, Charlotte; Knudsen, Nils; Ovesen, Lars

    2011-01-01

    of salt was initiated in 1998 because of mild-to-moderate iodine deficiency. The aim of this study was to evaluate the effect of the raised iodine intake on the nationwide incident use of thyroid hormone replacement therapy (levothyroxine) to treat hypothyroidism. Data on all use of levothyroxine...... for caution when initiating iodine fortification programs to keep the intake within the optimal range, and the need for continuous monitoring....

  19. Amiodarone: Effects on thyroid function and the peripheral metabolism of the thyroid hormones

    Energy Technology Data Exchange (ETDEWEB)

    Braverman, L.E.; Safran, M.; Bambini, G.; Pinchera, A.; Martino, E.

    1985-11-01

    In addition to the effects of Amiodarone on the peripheral metabolism of the thyroid hormones and on pituitary TSH secretion, a major complication of therapy is the relatively high frequency of iodide-induced thyroid dysfunction. The mean T/sub 4/ and T/sub 3/ concentration following Amiodarone application was measured in euthyroid, hypothyroid and hyperthyroid patients and in control patients with and without cardiac disorders. Furthermore, the serum TSH was determined in euthyroid Amiodarone-treated euthyroid patients. /sup 131/I uptake was studied in patients with Amiodarone-associated thyrotoxicosis. The difficulties of the therapy of Amiodarone-induced hyperthyroidism are outlined. Preliminary studied of the effect of Amiodarone and its analogues on the metabolism of thyroid hormones in the rat indicate that Amiodarone may act as a thyroid hormone agonist in the pituitary. (MG).

  20. Hypophysectomy abolishes rhythms in rat thyroid hormones but not in the thyroid clock.

    Science.gov (United States)

    Fahrenkrug, J; Georg, B; Hannibal, J; Jørgensen, H L

    2017-06-01

    The endocrine body rhythms including the hypothalamic-pituitary-thyroid axis seem to be regulated by the circadian timing system, and daily rhythmicity of circulating thyroid-stimulating hormone (TSH) is well established. The circadian rhythms are generated by endogenous clocks in the central brain oscillator located in the hypothalamic suprachiasmatic nucleus (SCN) as well as multiple peripheral clocks, but information on the existence and function of a thyroid clock is limited. The molecular machinery in all clock cells is composed of a number of clock genes and their gene products are connected by autoregulatory feedback loops. Here, we provide evidence for a thyroid clock in the rat by demonstrating 24-h antiphase oscillations for the mRNA of the canonical clock genes Per1 and Bmal1 , which was unaffected by hypophysectomy. By immunostaining, we supported the existence of a core oscillator in the individual thyroid cells by demonstrating a daily cytoplasmatic-nuclear shuttling of PER1 protein. In normal rats, we found a significant daily rhythmicity in the circulating thyroid hormones preceded by a peak in TSH. In hypophysectomised rats, although the thyroid clock was not affected, the oscillations in circulating thyroid hormones were abolished and the levels were markedly lowered. No daily oscillations in the expression of TSH receptor mRNA were observed in neither control rats nor hypophysectomised rats. Our findings indicate that the daily rhythm of thyroid hormone secretion is governed by SCN signalling via the rhythmic TSH secretion rather than by the local thyroid clock, which was still ticking after hypophysectomy. © 2017 The authors.

  1. Aspects of peripheral thyroid hormone metabolism

    NARCIS (Netherlands)

    M.H. Otten (Marten Henk)

    1984-01-01

    textabstractThe research into thyroid function has a long history. The recognition of goiter as pathology of the thyroid gland dates back to the ancient world of Rome and Greece and possibly even to the early history of chinese medicine. In an excellent review of the historical aspects of the

  2. Thyroid hormone metabolism during inflammation and fasting

    NARCIS (Netherlands)

    de Vries, E.M.

    2015-01-01

    Pathophysiological circumstances such as illness and fasting affect the hypothalamus-pituitary-thyroid (HPT)-axis. The illness induced alterations, collectively known as the non-thyroidal illness syndrome (NTIS) are characterized by decreased serum T3 and T4 concentrations, increased serum rT3

  3. Thyroid Hormone and the Neuroglia: Both Source and Target

    Science.gov (United States)

    Mohácsik, Petra; Zeöld, Anikó; Bianco, Antonio C.; Gereben, Balázs

    2011-01-01

    Thyroid hormone plays a crucial role in the development and function of the nervous system. In order to bind to its nuclear receptor and regulate gene transcription thyroxine needs to be activated in the brain. This activation occurs via conversion of thyroxine to T3, which is catalyzed by the type 2 iodothyronine deiodinase (D2) in glial cells, in astrocytes, and tanycytes in the mediobasal hypothalamus. We discuss how thyroid hormone affects glial cell function followed by an overview on the fine-tuned regulation of T3 generation by D2 in different glial subtypes. Recent evidence on the direct paracrine impact of glial D2 on neuronal gene expression underlines the importance of glial-neuronal interaction in thyroid hormone regulation as a major regulatory pathway in the brain in health and disease. PMID:21876836

  4. Thyroid Hormone and the Neuroglia: Both Source and Target

    Directory of Open Access Journals (Sweden)

    Petra Mohácsik

    2011-01-01

    Full Text Available Thyroid hormone plays a crucial role in the development and function of the nervous system. In order to bind to its nuclear receptor and regulate gene transcription thyroxine needs to be activated in the brain. This activation occurs via conversion of thyroxine to T3, which is catalyzed by the type 2 iodothyronine deiodinase (D2 in glial cells, in astrocytes, and tanycytes in the mediobasal hypothalamus. We discuss how thyroid hormone affects glial cell function followed by an overview on the fine-tuned regulation of T3 generation by D2 in different glial subtypes. Recent evidence on the direct paracrine impact of glial D2 on neuronal gene expression underlines the importance of glial-neuronal interaction in thyroid hormone regulation as a major regulatory pathway in the brain in health and disease.

  5. Role of Thyroid Hormones in Skeletal Development and Bone Maintenance

    Science.gov (United States)

    Bassett, J. H. Duncan

    2016-01-01

    The skeleton is an exquisitely sensitive and archetypal T3-target tissue that demonstrates the critical role for thyroid hormones during development, linear growth, and adult bone turnover and maintenance. Thyrotoxicosis is an established cause of secondary osteoporosis, and abnormal thyroid hormone signaling has recently been identified as a novel risk factor for osteoarthritis. Skeletal phenotypes in genetically modified mice have faithfully reproduced genetic disorders in humans, revealing the complex physiological relationship between centrally regulated thyroid status and the peripheral actions of thyroid hormones. Studies in mutant mice also established the paradigm that T3 exerts anabolic actions during growth and catabolic effects on adult bone. Thus, the skeleton represents an ideal physiological system in which to characterize thyroid hormone transport, metabolism, and action during development and adulthood and in response to injury. Future analysis of T3 action in individual skeletal cell lineages will provide new insights into cell-specific molecular mechanisms and may ultimately identify novel therapeutic targets for chronic degenerative diseases such as osteoporosis and osteoarthritis. This review provides a comprehensive analysis of the current state of the art. PMID:26862888

  6. Role of Thyroid Hormones in Skeletal Development and Bone Maintenance.

    Science.gov (United States)

    Bassett, J H Duncan; Williams, Graham R

    2016-04-01

    The skeleton is an exquisitely sensitive and archetypal T3-target tissue that demonstrates the critical role for thyroid hormones during development, linear growth, and adult bone turnover and maintenance. Thyrotoxicosis is an established cause of secondary osteoporosis, and abnormal thyroid hormone signaling has recently been identified as a novel risk factor for osteoarthritis. Skeletal phenotypes in genetically modified mice have faithfully reproduced genetic disorders in humans, revealing the complex physiological relationship between centrally regulated thyroid status and the peripheral actions of thyroid hormones. Studies in mutant mice also established the paradigm that T3 exerts anabolic actions during growth and catabolic effects on adult bone. Thus, the skeleton represents an ideal physiological system in which to characterize thyroid hormone transport, metabolism, and action during development and adulthood and in response to injury. Future analysis of T3 action in individual skeletal cell lineages will provide new insights into cell-specific molecular mechanisms and may ultimately identify novel therapeutic targets for chronic degenerative diseases such as osteoporosis and osteoarthritis. This review provides a comprehensive analysis of the current state of the art.

  7. Comments to guidelines for the treatment of hypothyroidism prepared by the American thyroid association task force on thyroid hormone replacement

    Directory of Open Access Journals (Sweden)

    Valentin Viktorovich Fadeev

    2015-02-01

    Full Text Available The article is dedicated to the discussion about to guidelines for the treatment of hypothyroidism prepared by the American thyroid association task force on thyroid hormone replacement.

  8. Inter-individual differences in thyroid hormone bioactivity: the effect of genetic variation

    NARCIS (Netherlands)

    W.M. van der Deure (Wendy)

    2009-01-01

    textabstractAdequate levels of thyroid hormone are essential for normal development and growth, since thyroid hormone plays an important role in virtually all metabolic processes in the human body. This is clearly demonstrated in patients with thyroid hormone disorders. Hyperthyroidism leads to high

  9. Lipid Profile and Thyroid Hormones in Types 1 and 2 Diabetics ...

    African Journals Online (AJOL)

    Medications used in treating each of the two classes of diabetes differ and the effect of the various hypoglycemic agents on thyroid hormones varies, while thyroid hormone levels relate inversely with cholesterol levels. We measured thyroid hormones and lipids levels in 18 Type 1 and 143 Type 2 diabetics using Enzyme ...

  10. Modulation of chronic excessive interleukin-6 production in multiple myeloma does not affect thyroid hormone concentrations

    NARCIS (Netherlands)

    van Zaanen, H. C.; Romijn, J. A.; Sauerwein, H. P.; Lokhorst, H. M.; Warnaar, S. O.; Aarden, L. A.; Endert, E.; van Oers, M. H.

    1997-01-01

    Interleukin-6 (IL6) is believed to be involved in alterations of thyroid hormone metabolism in acute nonthyroidal illness. To evaluate the effects of IL6 on thyroid hormone metabolism in a chronic IL6-mediated disease, we measured thyroid hormone concentrations in multiple myeloma patients treated

  11. [Reference Intervals of Thyroid Hormones in Normal Pregnant Women and Effects of Thyroid Autoantibodies on Thyroid Hormone Levels in Pregnant Women in Chengdu Area].

    Science.gov (United States)

    Chen, Yu-Min; Zeng, Jing; Yan, Yue-Rong; Luo, Dan; Huang, Lu; Huang, Hui

    2017-05-01

    To establish the reference intervals of thyroid hormones in normal pregnant women in Chengdu area of China, and to investigate the effects of thyroid autoantibodies on thyroid function in pregnant women. We included 696 pregnant women who had gestation data from June 2013 to March 2014 in Chengdu Women & Children's Central Hospital. Every subject under went questionnaire survey, physical examination, thyroid ultrasound and measurement of thyroid hormone and thyroid autoantibodies. The normal reference intervals were established according to the percentiles (P 2.5 -P 97.5 ) of the healthy pregnant women in the same trimester. Another 50 non-pregnant women were selected as the control group. Of the 696 pregnant women, 579 subjects had negative thyroid autoantibodies and 117 subjects had positive thyroid autoantibodies. The positive rate of thyroid autoantibodies was 16.81%. Of the 579 subjects with negative thyroid autoantibodies, 257 were in the first trimester, 202 in the second trimester and 120 in the third trimester. In the first trimester of normal pregnancy, the reference intervals of serum thyrotropin (TSH) , free triiodothyronine (FT3) and free thyroxine (FT4) were 0.02-4.03 mIU/L, 3.85-6.27 pmol/L and 11.93-21.04 pmol/L respectively. In the second trimester, the reference intervals of serum TSH, FT3 and FT4 were 0.02-4.05 mIU/L, 3.51-5.82 pmol/L and 11.23-19.22 pmol/L respectively. In the thirdtrimester, the reference intervals for serum TSH, FT3 and FT4 were 0.24-5.41 mIU/L, 3.18-4.97 pmol/L and 11.10-17.00 pmol/L, respectively. When compared with non-pregnant women, the median TSH value was increasingly consisted with the progress of pregnancy period, while the median FT4 and FT3 values were decreasing accordingly. The similar tendencies of TSH, FT3, and FT4 were found in pregnant women with positive thyroid autoantibodies, but the trends were more remarkable when compared with those with negative thyroid autoantibodies. In pregnant women with positive

  12. Thyroid hormone receptor binds to a site in the rat growth hormone promoter required for induction by thyroid hormone

    International Nuclear Information System (INIS)

    Koenig, R.J.; Brent, G.A.; Warne, R.L.; Larsen, P.R.; Moore, D.D.

    1987-01-01

    Transcription of the rat growth hormone (rGH) gene in pituitary cells is increased by addition of thyroid hormone (T3). This induction is dependent on the presence of specific sequences just upstream of the rGH promoter. The authors have partially purified T3 receptor from rat liver and examined its interaction with these rGH sequences. They show here that T3 receptor binds specifically to a site just upstream of the basal rGH promoter. This binding site includes two copies of a 7-base-pair direct repeat, the centers of which are separated by 10 base pairs. Deletions that specifically remove the T3 receptor binding site drastically reduce response to T3 in transient transfection experiments. These results demonstrate that T3 receptor can recognize specific DNA sequences and suggest that it can act directly as a positive transcriptional regulatory factor

  13. Behavioral Inhibition and Impaired Spatial Learning and Memory in Hypothyroid Mice Lacking Thyroid Hormone Receptor α

    Science.gov (United States)

    Wilcoxon, Jennifer Slone; Nadolski, Gregory J.; Samarut, Jacques; Chassande, Olivier; Redei, Eva E.

    2007-01-01

    Thyroid hormone insufficiency leads to impaired neurogenesis, behavioral alterations and cognitive deficits. Thyroid hormone receptors, expressed in brain regions involved in these behaviors, mediate the effects of thyroid hormone deficiency or excess. To determine the contribution of thyroid hormone receptor alpha (TRα) in these behaviors, we examined the behavior of euthyroid as well as hypo- and hyperthyroid mice lacking all isoforms of the TRα (TRαo/o). The hypothyroxinemic TRαo/o mice demonstrated behavioral inhibition, manifested in decreased activity and increased anxiety/fear in the open field test (OFT) and increased immobility in the forced swim test (FST) compared to C57BL/6J mice. TRαo/o mice also showed learning and recall impairments in the Morris water maze (MWM), which were exaggerated by hypothyroidism in TRαo/o mice. These impairments were concurrent with increased thigmotaxis, suggesting an increased anxiety-like state of the TRαo/o mice in the MWM. Expression of genes, known to be involved in processes modulating learning and memory, such as glucocorticoid receptor (GR), growth-associated protein 43 (GAP-43) and neurogranin (RC3), were significantly decreased in the hippocampus of TRαo/o mice. GR expression was also decreased in the frontal cortex and amygdala of TRαo/o mice, indicating that expression of GR is regulated, probably developmentally, by one or more isoforms of TRα in the mouse brain. Taken together these data demonstrate behavioral alterations in the TRαo/o mice, indicating the functional role of TRα, and a delicate interaction between TRα and TRβ-regulated genes in these behaviors. Thyroid hormone-regulated genes potentially responsible for the learning deficit found in TRαo/o mice include GR, RC3 and GAP-43. PMID:17129617

  14. 2,4,6-Tribromophenol Interferes with the Thyroid Hormone System by Regulating Thyroid Hormones and the Responsible Genes in Mice.

    Science.gov (United States)

    Lee, Dongoh; Ahn, Changhwan; Hong, Eui-Ju; An, Beum-Soo; Hyun, Sang-Hwan; Choi, Kyung-Chul; Jeung, Eui-Bae

    2016-07-12

    2,4,6-Tribromophenol (TBP) is a brominated flame retardant (BFR). Based on its affinity for transthyretin, TBP could compete with endogenous thyroid hormone. In this study, the effects of TBP on the thyroid hormone system were assessed in mice. Briefly, animals were exposed to 40 and 250 mg/kg TBP. Thyroid hormones were also administered with or without TBP. When mice were treated with TBP, deiodinase 1 (Dio1) and thyroid hormone receptor β isoform 2 (Thrβ2) decreased in the pituitary gland. The levels of deiodinase 2 (Dio2) and growth hormone (Gh) mRNA increased in response to 250 mg/kg of TBP, and the relative mRNA level of thyroid stimulating hormone β (Tshβ) increased in the pituitary gland. Dio1 and Thrβ1 expression in the liver were not altered, while Dio1 decreased in response to co-treatment with thyroid hormones. The thyroid gland activity decreased in response to TBP, as did the levels of free triiodothyronine and free thyroxine in serum. Taken together, these findings indicate that TBP can disrupt thyroid hormone homeostasis and the presence of TBP influenced thyroid actions as regulators of gene expression. These data suggest that TBP interferes with thyroid hormone systems.

  15. 2,4,6-Tribromophenol Interferes with the Thyroid Hormone System by Regulating Thyroid Hormones and the Responsible Genes in Mice

    Directory of Open Access Journals (Sweden)

    Dongoh Lee

    2016-07-01

    Full Text Available 2,4,6-Tribromophenol (TBP is a brominated flame retardant (BFR. Based on its affinity for transthyretin, TBP could compete with endogenous thyroid hormone. In this study, the effects of TBP on the thyroid hormone system were assessed in mice. Briefly, animals were exposed to 40 and 250 mg/kg TBP. Thyroid hormones were also administered with or without TBP. When mice were treated with TBP, deiodinase 1 (Dio1 and thyroid hormone receptor β isoform 2 (Thrβ2 decreased in the pituitary gland. The levels of deiodinase 2 (Dio2 and growth hormone (Gh mRNA increased in response to 250 mg/kg of TBP, and the relative mRNA level of thyroid stimulating hormone β (Tshβ increased in the pituitary gland. Dio1 and Thrβ1 expression in the liver were not altered, while Dio1 decreased in response to co-treatment with thyroid hormones. The thyroid gland activity decreased in response to TBP, as did the levels of free triiodothyronine and free thyroxine in serum. Taken together, these findings indicate that TBP can disrupt thyroid hormone homeostasis and the presence of TBP influenced thyroid actions as regulators of gene expression. These data suggest that TBP interferes with thyroid hormone systems

  16. 2,4,6-Tribromophenol Interferes with the Thyroid Hormone System by Regulating Thyroid Hormones and the Responsible Genes in Mice

    Science.gov (United States)

    Lee, Dongoh; Ahn, Changhwan; Hong, Eui-Ju; An, Beum-Soo; Hyun, Sang-Hwan; Choi, Kyung-Chul; Jeung, Eui-Bae

    2016-01-01

    2,4,6-Tribromophenol (TBP) is a brominated flame retardant (BFR). Based on its affinity for transthyretin, TBP could compete with endogenous thyroid hormone. In this study, the effects of TBP on the thyroid hormone system were assessed in mice. Briefly, animals were exposed to 40 and 250 mg/kg TBP. Thyroid hormones were also administered with or without TBP. When mice were treated with TBP, deiodinase 1 (Dio1) and thyroid hormone receptor β isoform 2 (Thrβ2) decreased in the pituitary gland. The levels of deiodinase 2 (Dio2) and growth hormone (Gh) mRNA increased in response to 250 mg/kg of TBP, and the relative mRNA level of thyroid stimulating hormone β (Tshβ) increased in the pituitary gland. Dio1 and Thrβ1 expression in the liver were not altered, while Dio1 decreased in response to co-treatment with thyroid hormones. The thyroid gland activity decreased in response to TBP, as did the levels of free triiodothyronine and free thyroxine in serum. Taken together, these findings indicate that TBP can disrupt thyroid hormone homeostasis and the presence of TBP influenced thyroid actions as regulators of gene expression. These data suggest that TBP interferes with thyroid hormone systems PMID:27420076

  17. DEHP reduces thyroid hormones via interacting with hormone synthesis-related proteins, deiodinases, transthyretin, receptors, and hepatic enzymes in rats.

    Science.gov (United States)

    Liu, Changjiang; Zhao, Letian; Wei, Li; Li, Lianbing

    2015-08-01

    Di-(2-ethylhexyl) phthalate (DEHP) is used extensively in many personal care and consumer products, resulting in widespread nonoccupational human exposure through multiple routes and media. Limited studies suggest that exposure to DEHP may be associated with altered thyroid function, but detailed mechanisms are unclear. In order to elucidate potential mechanisms by which DEHP disturbs thyroid hormone homeostasis, Sprague-Dawley (SD) rats were dosed with DEHP by gavage at 0, 250, 500, and 750 mg/kg/day for 30 days and sacrificed within 24 h after the last dose. Gene expressions of thyroid hormone receptors, deiodinases, transthyretin, and hepatic enzymes were measured by RT-PCR; protein levels of transthyretin were also analyzed by Western blot. Results showed that DEHP caused histological changes in the thyroid and follicular epithelial cell hypertrophy and hyperplasia were observed. DEHP significantly reduced thyroid hormones (T3, T4) and thyrotropin releasing hormone (TRH) levels, whereas thyroid stimulating hormone (TSH) was not affected. After exposure to DEHP, biosynthesis of thyroid hormones was suppressed, and sodium iodide symporter (NIS) and thyroid peroxidase (TPO) levels were significantly reduced. Additionally, levels of deiodinases and transthyretin were also affected. TSH receptor (TSHr) level was downregulated, while TRH receptor (TRHr) level was upregulated. Metabolism of thyroid hormones was accelerated due to elevated gene expression of hepatic enzymes (UDPGTs and CYP2B1) by DEHP. Taken together, observed findings indicate that DEHP could reduce thyroid hormones through influencing biosynthesis, biotransformation, biotransport, receptor levels, and metabolism of thyroid hormones.

  18. Iodine deficiency up-regulates monocarboxylate transporter 8 expression of mouse thyroid gland.

    Science.gov (United States)

    Hu, Zhimei; Zhuo, Xiaohua; Shi, Yanan; Liu, Xin; Yuan, Jihong; Li, Lanying; Sun, Yina

    2014-01-01

    Iodine deficiency is a major factor affecting thyroid auto-regulation, the quantity of iodine may greatly influence the synthesis of thyroid hormones (THs). It has long been believed that TH enters the cell through passive diffusion. Recent studies have suggested that several transporters could facilitate transportation of TH. The monocarboxylate transporter 8 (MCT8) was identified as a very active and specific TH transporter. The purpose of this study was to investigate whether iodine insufficient affected the expression of MCT8 in the thyroid gland. Sixty BALB/c mice were randomly divided into two groups: control group was fed with standard feed (iodine concentration of 300 µg/kg); while low-iodine (LI) group received iodine-insufficient feed (iodine concentration of 20-40 µg/kg). After 3 months, 10 mice of each group were sacrificed. The remaining 20 mice of each group were kept till 6 months. From the LI group, we randomly selected 15 mice and injected triiodothyronine (T3, 100 µg/kg body weight per day) intraperitoneally for 24, 48 or 72 hours (5 mice for each time-point). Then, all the mice were sacrificed. Mouse serum thyroxine (T4), T3, and thyroid-stimulating hormone (TSH) levels were determined by chemiluminescence immunoassay (CIA). The protein content or messenger RNA (mRNA) level of thyroid MCT8 was measured by Western blotting analysis or real time RT-PCR respectively. MCT8 subcellular location in thyroid tissues was probed with immunohistochemistry (IHC) assay. We found that mouse serum T3 and T4 levels decreased and TSH level increased by the end of the third month. Consistent with these findings, there was significant goiter and hypothyroidism in the LI group. Meanwhile, the MCT8 mRNA increased to 1.36-fold of the level in the control group at the 3(rd) month. At 6(th) month, the serum T4 level in LI mice remained at a lower level, and MCT8 mRNA expression continued rising to nearly 1.60-fold compared with the control group. The protein content

  19. Substances that disrupt thyroid hormone biosynthesis (in Romanian

    Directory of Open Access Journals (Sweden)

    Pap, Andreea

    2015-06-01

    Full Text Available Endocrine disrupters are natural or synthetic chemical substances that have the possibility to alter the endocrine functions leading to serious metabolic changes especially in newborns. The accumulation and persistence over long periods of time became a priority in terms of health and environment. The mechanism of action is represented by blocking, mimicking or modifying the effects of thyroid hormones. In this review, the main purpose was to determine what effects have the endocrine disruptors on the thyroid gland, especially on the thyroid hormone biosynthesis and setting the stage involved by it. We focused on the action of perchlorates, phthalates, BPC, PDPEs, soy, isoflavones, nitrates, thiocyanates, bisphenol A and triclorsan and came to the conclusion that their intervention can result in either hyperthyroidism or hypothyroidism.

  20. The Influence of Thyroid Hormones on Gamma Immunoglobulin ...

    African Journals Online (AJOL)

    Ex-vivo placenta, maternal and cord blood of twenty deliveries (10 primipara and ten multipara; five of which were by elective caesarean section) were assayed for thyroid hormone in maternal serum and IgGp in maternal and cord sera; while the APGAR scores of the neonates were as well, documented. Results showed ...

  1. Serum Levels of Thyroid Hormones and Thyrotropin in Some Sickle ...

    African Journals Online (AJOL)

    The serum levels of the thyroid hormones (T4 and T3) and thyrotropin (TSH) were measured by radio-immunoassay (RIA) in the steady state of 10 homozygous sickle cell anaemia patients and 10 normal subjects of the same age group in years (15-25) who were the control group. The results showed that sickle cell disease ...

  2. Thyroid hormone: the modulator of erectile function in the rabbit ...

    African Journals Online (AJOL)

    The possible role of thyroid hormones in the Nitric Oxide (NO)- mediated response to sexual stimulation, and on prostaglandin E1 (PGE1) and Sildenafil in the treatment of erectile dysfunction was investigated using the corpus cavernosum of the New Zealand rabbit animal model. The parameters studied were penile ...

  3. The deiodination of thyroid hormone in rat liver

    NARCIS (Netherlands)

    J.A. Mol

    1985-01-01

    textabstractAs mentioned in the preceding paragraphs, enzymatic deiodination of T4 is the most important route for the production of the biologically active thyroid hormone, T3• The liver is regarded as the principal site for the peripheral production of T3. Besides deiodination the liver is also

  4. DE71 suppresses thyroid hormone-mediated dendritogenesis and ...

    African Journals Online (AJOL)

    olayemitoyin

    DE71 suppresses thyroid hormone-mediated dendritogenesis and neuritogenesis in the developing cerebellum. *1,2. Ibhazehiebo Kingsley,. 1. Koibuchi Noriyuki. 1Department of Integrative Physiology, Gunma University Graduate School of Medicine, Maebashi, Japan. 2Department of Physiology, School of Basic Medical ...

  5. Thyroid Stimulating Hormone values from cord blood in neonates ...

    African Journals Online (AJOL)

    Objectives: To determine thyroid stimulating hormone (TSH) levels from cord blood in neonates and to establish the practice for possible application of congenital hypothyroidism screening in Ethiopia. Methods: TSH was measured from cord blood of 1207 consecutive new-borns in the maternal wards of St. Paul, Ghandi ...

  6. Histological structure and hormonal profile of pituitary and thyroid ...

    African Journals Online (AJOL)

    This study aims to evaluate the effects of castration and iodine supplementaion on the histological structure of pituitary and thyroid glands and their related hormones in NZW male rabbits. Animals were randomly divided into two groups. The first group was supplemented with iodine as potassium iodide at a level of 400 ppm ...

  7. Dependence of calcium on thyroid hormone for the regulation of ...

    African Journals Online (AJOL)

    concentration by mobilizing intracellular Ca2+. The mobilization of intracellular Ca2+in the absence of transmembrane Ca2+influx has been accepted as evidence for a cell-surface Ca2+ - receptor. The possible role of thyroid hormone in the ...

  8. [Relationship between maternal milk and serum thyroid hormones in patients with thyroid related diseases].

    Science.gov (United States)

    Zhang, Qian; Lian, Xiao-lan; Chai, Xiao-feng; Bai, Yao; Dai, Wei-xin

    2013-08-01

    To explore the relationship between maternal milk and serum thyroid hormones in patients with thyroid-related diseases. Serum and breast milk samples were collected from 56 breastfeeding mothers. Milk and serum free triiodothyronine (FT3), free thyroxine (FT4), triiodothyronine(T3), thyroxine (T4), and thyrotrophin (TSH) were determined, and T3/T4 was calculated. Using the serum thyroid hormones as the independent variables and milk thyroid hormones as the dependent variables, we performed linear regression analysis. The milk FT3, FT4, T3, T4, TSH, and T3/T4 were (2.30 ± 0.82) pg/ml ,(0.45 ± 0.26) ng/dl, (0.35 ± 0.20) ng/ml, (2.96 ± 1.55) Μg/dl, (0.12 ± 0.08) ΜU/ml, and 0.12 ± 0.04, respectively. Milk FT3 (r = 0.778, P = 0.000), T3 (r = 0.603, P = 0.000), T4 (r = 0.485, P = 0.004), and TSH (r = 0.605, P = 0.000) concentrations were positively correlated with those in serum. Thyroid hormones are present in human milk and are positively correlated with those in serum.

  9. Ocular Myasthenia Gravis, Hashimoto’s Thyroiditis, Iron Deficiency Anemia, and Reactive Hypoglycemia

    Directory of Open Access Journals (Sweden)

    Füsun Mayda Domaç

    2009-06-01

    Full Text Available Myasthenia gravis (MG may occur in association with other organ- specific or nonspecific autoimmune diseases. In our study, we present a patient with ocular myasthenia, Hashimoto’s thyroiditis, and iron deficiency anemia who later developed reactive hypoglycemia. A 25-year-old woman with complaints of fluctuating extraocular muscle weakness, ptosis, and diplopia was examined. MG, type I (ocular MG, was confirmed by an elevated titer of anti-acetylcholine receptor antibodies in serum (7 nmol/l, normal <0.6 and positive edrophonium test. Nerve conduction studies, needle electromyography, repetitive stimulation tests, and mediasten MRI were normal. The coexistence of Hashimoto's thyroiditis was diagnosed by the presence of a diffuse thyroid enlargement, elevated titers of anti-thyroglobulin antibodies (211.8 IU/ml, normal 0-115, thyroid peroxidase antibodies (356.4 IU/ml, normal 0-34, thyroid stimulating hormone (8.21 uIU/ml, normal 0.27-4.2, and a decreased titer of free-T4 (1.03ng/dl normal 1.8-4.6. Diplopia and ptosis have regressed with 180 mg/day pyridostigmine bromide. On her follow-up period, 8 months later, reactive hypoglycemia has been diagnosed. The coexistence of myastenia gravis, Hashimoto’s thyroiditis and reactive hypoglycemia was not found in the literature. We should take into consideration the association and the importance of recognizing and treating these pathologies in myastenia gravis. Turk Jem 2009; 13: 31-3

  10. Alternative complement pathway and factor B activities in rats with altered blood levels of thyroid hormone

    International Nuclear Information System (INIS)

    Bitencourt, C.S.; Duarte, C.G.; Azzolini, A.E.C.S.; Assis-Pandochi, A.I.

    2012-01-01

    Evaluating the activity of the complement system under conditions of altered thyroid hormone levels might help elucidate the role of complement in triggering autoimmune processes. Here, we investigated alternative pathway (AP) activity in male Wistar rats (180 ± 10 g) after altering their thyroid hormone levels by treatment with triiodothyronine (T3), propylthiouracil (PTU) or thyroidectomy. T3 and thyroxine (T4) levels were determined by chemiluminescence assays. Hemolytic assays were performed to evaluate the lytic activity of the AP. Factor B activity was evaluated using factor B-deficient serum. An anti-human factor B antibody was used to measure factor B levels in serum by radial immunodiffusion. T3 measurements in thyroidectomized animals or animals treated with PTU demonstrated a significant reduction in hormone levels compared to control. The results showed a reduction in AP lytic activity in rats treated with increasing amounts of T3 (1, 10, or 50 µg). Factor B activity was also decreased in the sera of hyperthyroid rats treated with 1 to 50 µg T3. Additionally, treating rats with 25 µg T3 significantly increased factor B levels in their sera (P < 0.01). In contrast, increased factor B concentration and activity (32%) were observed in hypothyroid rats. We conclude that alterations in thyroid hormone levels affect the activity of the AP and factor B, which may in turn affect the roles of AP and factor B in antibody production

  11. Thyroid hormone receptor isoform selectivity of thyroid hormone disrupting compounds quantified with an in vitro reporter gene assay

    NARCIS (Netherlands)

    Schriks, M.; Roessig, J.M.; Murk, A.J.; Furlow, J.D.

    2007-01-01

    Some compounds, including brominated diphenyl ethers (BDEs), can interfere with thyroid hormone (TH) receptor (TR)-mediated TH-signalling. In this study, the TR isoform selectivity of some TH disrupting compounds was investigated with TR alpha/beta specific reporter gene assays. For this purpose,

  12. Thyroid hormone concentrations in dialysate during hemodialysis in children

    International Nuclear Information System (INIS)

    Waters, W.; Bulla, M.; Buschsieweke, U.; Kutzim, H.; Koeln Univ.

    1981-01-01

    Thyroxine (T4) concentration in dialysate in the course of hemodialysis was determined in 15 children. Concentrations were measured by a modified radioimmunoassay. During hemodialysis there was a slight increase in T4 concentration. At the end of hemodialysis T4 concentration was about 50% higher than soon after the onset of hemodialysis. The loss of T4 into dialysate during hemodialysis was 19.2 μg; the loss of T3 was less than 75 ng. The amount of the daily loss of thyroid hormones into dialysate was found to be in the range of normal urinary excretion. The lowering of serum thyroid hormone concentrations in children on hemodialysis cannot be explained by the loss of these hormones into dialysate. (orig.) [de

  13. prevalence and severity of iodine deficiency

    African Journals Online (AJOL)

    GB

    2012-11-03

    Nov 3, 2012 ... Iodine deficiency causes reduced production of thyroid hormones (T3/T4). A decrease in the serum level of T3/T4 triggers the secretion of high amount of pituitary thyroid stimulating hormone, which stimulates thyroid glandular activities that results in enlargement of the gland (9). Thyroid hormones play an ...

  14. Gestational urinary bisphenol A and maternal and newborn thyroid hormone concentrations: The HOME Study

    Energy Technology Data Exchange (ETDEWEB)

    Romano, Megan E., E-mail: megan_romano@brown.edu [Department of Epidemiology, Brown University School of Public Health, Providence, RI (United States); Webster, Glenys M. [Child and Family Research Institute, BC Children' s and Women' s Hospital and Faculty of Health Sciences, Simon Fraser University, Vancouver, British Columbia (Canada); Vuong, Ann M. [Division of Epidemiology and Biostatistics, Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, OH (United States); Thomas Zoeller, R. [Department of Biology, University of Massachusetts, Amherst, MA (United States); Chen, Aimin [Division of Epidemiology and Biostatistics, Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, OH (United States); Hoofnagle, Andrew N. [Department of Laboratory Medicine, University of Washington, Seattle, WA (United States); Calafat, Antonia M. [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA (United States); Karagas, Margaret R. [Children' s Environmental Health and Disease Prevention Research Center and Department of Community and Family Medicine, Geisel School of Medicine at Dartmouth, Hanover, NH (United States); Yolton, Kimberly [Division of General and Community Pediatrics, Department of Pediatrics, Cincinnati Children' s Hospital Medical Center, Cincinnati, OH (United States); Lanphear, Bruce P. [Child and Family Research Institute, BC Children' s and Women' s Hospital and Faculty of Health Sciences, Simon Fraser University, Vancouver, British Columbia (Canada); Braun, Joseph M. [Department of Epidemiology, Brown University School of Public Health, Providence, RI (United States)

    2015-04-15

    Bisphenol A (BPA), an endocrine disruptor used in consumer products, may perturb thyroid function. Prenatal BPA exposure may have sex-specific effects on thyroid hormones (THs). Our objectives were to investigate whether maternal urinary BPA concentrations during pregnancy were associated with THs in maternal or cord serum, and whether these associations differed by newborn sex or maternal iodine status. We measured urinary BPA concentrations at 16 and 26 weeks gestation among pregnant women in the HOME Study (2003–2006, Cincinnati, Ohio). Thyroid stimulating hormone (TSH) and free and total thyroxine (T{sub 4}) and triiodothyronine (T{sub 3}) were measured in maternal serum at 16 weeks (n=181) and cord serum at delivery (n=249). Associations between BPA concentrations and maternal or cord serum TH levels were estimated by multivariable linear regression. Mean maternal urinary BPA was not associated with cord THs in all newborns, but a 10-fold increase in mean BPA was associated with lower cord TSH in girls (percent change=−36.0%; 95% confidence interval (CI): −58.4, −1.7%), but not boys (7.8%; 95% CI: −28.5, 62.7%; p-for-effect modification=0.09). We observed no significant associations between 16-week BPA and THs in maternal or cord serum, but 26-week maternal BPA was inversely associated with TSH in girls (−42.9%; 95% CI: −59.9, −18.5%), but not boys (7.6%; 95% CI: −17.3, 40.2%; p-for-effect modification=0.005) at birth. The inverse BPA–TSH relation among girls was stronger, but less precise, among iodine deficient versus sufficient mothers. Prenatal BPA exposure may reduce TSH among newborn girls, particularly when exposure occurs later in gestation. - Highlights: • Examined associations of BPA with thyroid hormones in pregnant women and newborns. • Assessed effect modification of BPA–thyroid hormone associations by newborn sex. • Greater BPA related to decreased thyroid stimulating hormone in girls' cord serum. • Results may

  15. Gestational urinary bisphenol A and maternal and newborn thyroid hormone concentrations: The HOME Study

    International Nuclear Information System (INIS)

    Romano, Megan E.; Webster, Glenys M.; Vuong, Ann M.; Thomas Zoeller, R.; Chen, Aimin; Hoofnagle, Andrew N.; Calafat, Antonia M.; Karagas, Margaret R.; Yolton, Kimberly; Lanphear, Bruce P.; Braun, Joseph M.

    2015-01-01

    Bisphenol A (BPA), an endocrine disruptor used in consumer products, may perturb thyroid function. Prenatal BPA exposure may have sex-specific effects on thyroid hormones (THs). Our objectives were to investigate whether maternal urinary BPA concentrations during pregnancy were associated with THs in maternal or cord serum, and whether these associations differed by newborn sex or maternal iodine status. We measured urinary BPA concentrations at 16 and 26 weeks gestation among pregnant women in the HOME Study (2003–2006, Cincinnati, Ohio). Thyroid stimulating hormone (TSH) and free and total thyroxine (T 4 ) and triiodothyronine (T 3 ) were measured in maternal serum at 16 weeks (n=181) and cord serum at delivery (n=249). Associations between BPA concentrations and maternal or cord serum TH levels were estimated by multivariable linear regression. Mean maternal urinary BPA was not associated with cord THs in all newborns, but a 10-fold increase in mean BPA was associated with lower cord TSH in girls (percent change=−36.0%; 95% confidence interval (CI): −58.4, −1.7%), but not boys (7.8%; 95% CI: −28.5, 62.7%; p-for-effect modification=0.09). We observed no significant associations between 16-week BPA and THs in maternal or cord serum, but 26-week maternal BPA was inversely associated with TSH in girls (−42.9%; 95% CI: −59.9, −18.5%), but not boys (7.6%; 95% CI: −17.3, 40.2%; p-for-effect modification=0.005) at birth. The inverse BPA–TSH relation among girls was stronger, but less precise, among iodine deficient versus sufficient mothers. Prenatal BPA exposure may reduce TSH among newborn girls, particularly when exposure occurs later in gestation. - Highlights: • Examined associations of BPA with thyroid hormones in pregnant women and newborns. • Assessed effect modification of BPA–thyroid hormone associations by newborn sex. • Greater BPA related to decreased thyroid stimulating hormone in girls' cord serum. • Results may suggest

  16. Influence of maternal thyroid hormones during gestation on fetal brain development

    Science.gov (United States)

    Moog, Nora K.; Entringer, Sonja; Heim, Christine; Wadhwa, Pathik D.; Kathmann, Norbert; Buss, Claudia

    2015-01-01

    Thyroid hormones (TH) play an obligatory role in many fundamental processes underlying brain development and maturation. The developing embryo/fetus is dependent on maternal supply of TH. The fetal thyroid gland does not commence THs synthesis until mid gestation, and the adverse consequences of severe maternal TH deficiency on offspring neurodevelopment are well established. Recent evidence suggests that even more moderate forms of maternal thyroid dysfunction, particularly during early gestation, may have a long-lasting influence on child cognitive development and risk of neurodevelopmental disorders. Moreover, these observed alterations appear to be largely irreversible after birth. It is, therefore, important to gain a better understanding of the role of maternal thyroid dysfunction on offspring neurodevelopment in terms of the nature, magnitude, time-specificity, and context-specificity of its effects. With respect to the issue of context specificity, it is possible that maternal stress and stress-related biological processes during pregnancy may modulate maternal thyroid function. The possibility of an interaction between the thyroid and stress systems in the context of fetal brain development has, however, not been addressed to date. We begin this review with a brief overview of TH biology during pregnancy and a summary of the literature on its effect on the developing brain. Next, we consider and discuss whether and how processes related to maternal stress and stress biology may interact with and modify the effects of maternal thyroid function on offspring brain development. We synthesize several research areas and identify important knowledge gaps that may warrant further study. The scientific and public health relevance of this review relates to achieving a better understanding of the timing, mechanisms and contexts of thyroid programming of brain development, with implications for early identification of risk, primary prevention and intervention. PMID

  17. Serum thyroid hormone concentrations in relation to some physiological parameters in goats

    International Nuclear Information System (INIS)

    Dutta, D.J.; Sarmah, B.K.; Bhattacharyya, B.N.; Baruah, K.K.; Sarmah, B.C.; Goswami, J.

    2002-01-01

    Thyroid hormones are thought to be necessary for the utilization of hypophyseal and gonadal hormones apart from their normal functions related to basal metabolism and growth. The environmental stress also exerts pronounced effect on the biochemical characteristics of blood and hormonal response particularly in thyroid gland which are necessary for physiological adjustment. The present experiment was undertaken to study the levels of serum thyroid hormones in relation to age, sex and diurnal variation indigenous goats to Assam

  18. Thyroid hormone level and weight reduction

    OpenAIRE

    Thätner, Cathleen

    2013-01-01

    Understanding of the development and therapy of obesity is of large interest. Many different causes for obesity are assumed including endocrine diseases like hypothyroidism. There are studies showing endocrine changes as a consequence of massive weight reduction after bariatric surgery or liquid formula diet. The aim of this study was to investigate the association between thyroid function and weight reduction by lifestyle intervention programme. This programme consisted of nutritional edu...

  19. Thyroid stimulating hormone levels in cord blood are not influenced by non-thyroidal mothers' diseases

    Directory of Open Access Journals (Sweden)

    Laura Sterian Ward

    2000-09-01

    Full Text Available CONTEXT: Screening programs not only offer the opportunity to trace and treat almost all cases of congenital hypothyroidism but also mean large savings to the health system. However, carefully planned strategies are necessary to extend their benefits and reduce costs. OBJECTIVE: To determine the possible influence of maternal diseases that affect maternal-fetal placenta dynamics on primary thyroid stimulating hormone (TSH screening for congenital hypothyroidism. DESIGN: Prospective non-randomized clinical trial with at least 3 months of follow-up. SETTING: A public university referral center [CAISM/Hospital das Clínicas, Faculty of Medicine, University of Campinas, Campinas, SP]. PARTICIPANTS: 415 neonates divided into 5 groups: eighty-three infants born from cardiac mothers; 98 from mothers that had toxemia; 54 of the mothers had diabetes mellitus; 40 were HIV positive and 140 had no diseases. INTERVENTION: All newborns had cord blood samples collected on filter paper at birth. MAIN MEASUREMENTS: TSH was measured from dried blood spots using a homemade immunofluorescence assay (sensitivity in dried blood spots = 0.1 mU/L. RESULTS: There was no significant difference in the mean TSH levels among the 5 groups. Moreover, TSH levels were around 5 mU/L in 48% of the newborns, indicating that our region is severely deficient in iodine. CONCLUSIONS: Our results indicate that primary TSH screening programs using cord blood are not affected by maternal diseases. We suggest that, besides its technical advantages over heel punctures with T4 primary approaches, neonatal screening using primary cord blood TSH may also be used as a monitoring tool for evaluation and control of iodine deficiency disorders (IDD.

  20. Determination of the concentration of thyroid hormone in dialysate and assessment of the loss of thyroid hormone during hemodialysis

    International Nuclear Information System (INIS)

    Beyer, H.K.; Schuster, P.; Pressler, H.; Bochum Univ.

    1980-01-01

    In order to determine the hormone concentration in a dialysate, the commercially available radioimmunossay test of Dow-Lepetit for determination of free thyroid hormones in serum had to be modified. The results raised the suspicion that additional protein-bound hormone had passed the membrane. This could be demonstrated by the addition of Thiomersal. In 64 patients examined 1 and 5 hrs after the beginning of hemodialysis the mean total hormone concentration in the dialysate was 12.05 pg/ml for thyroxine and 5.47 pg/ml for triiodothyronine. The resulting loss of total hormone in hemodialysis patients, calculated for 1 week, amounted to 2.25 μg triiodothyronine and 4.87 μg thyroxine. The comparison with the physiologic renal elimination of thyroid hormone shows that the hormone elimination in hemodialysis patients is negligibly small. The quantitative determination of the protein concentration in the dialysate however, that the loss of protein is without clinical relevance. (orig.) [de

  1. Hypophysectomy abolishes rhythms in rat thyroid hormones but not in the thyroid clock

    DEFF Research Database (Denmark)

    Fahrenkrug, J; Georg, B; Hannibal, J

    2017-01-01

    The endocrine body rhythms including the hypothalamic-pituitary-thyroid axis seem to be regulated by the circadian timing system, and daily rhythmicity of circulating thyroid-stimulating hormone (TSH) is well established. The circadian rhythms are generated by endogenous clocks in the central brain...... oscillator located in the hypothalamic suprachiasmatic nucleus (SCN) as well as multiple peripheral clocks, but information on the existence and function of a thyroid clock is limited. The molecular machinery in all clock cells is composed of a number of clock genes and their gene products are connected...... by autoregulatory feedback loops. Here, we provide evidence for a thyroid clock in the rat by demonstrating 24-h antiphase oscillations for the mRNA of the canonical clock genes Per1 and Bmal1, which was unaffected by hypophysectomy. By immunostaining, we supported the existence of a core oscillator...

  2. Effects of substitution and high-dose thyroid hormone therapy on deiodination, sulfoconjugation, and tissue thyroid hormone levels in prolonged critically ill rabbits

    NARCIS (Netherlands)

    Y. Debaveye (Yves); B. Ellger (Björn); L. Mebis (Liese); T.J. Visser (Theo); V.M. Darras (Veerle); G. van den Berghe (Greet)

    2008-01-01

    textabstractTo delineate the metabolic fate of thyroid hormone in prolonged critically ill rabbits, we investigated the impact of two dose regimes of thyroid hormone on plasma 3,3′-diiodothyronine (T2) and T4S, deiodinase type 1 (D1) and D3 activity, and tissue iodothyronine levels in liver and

  3. The road to nuclear receptors of thyroid hormone.

    Science.gov (United States)

    Tata, Jamshed R

    2013-07-01

    Early studies on the mechanism of action of thyroid hormone (TH) measured changes in enzyme activities following the addition of l-thyroxine (T4) and 3, 3', 5-triiodothyronine (T3) to tissue extracts and purified enzymes. As techniques for isolation of mitochondria, ribosomes, nuclei and chromatin, were increasingly refined, it became possible to study complex cellular processes, such as oxidative phosphorylation, protein synthesis, transcription and chromosomal structure. Uncoupling of oxidative phosphorylation and direct action on protein synthesis as mechanisms of action of TH, proposed in the 1950s and 1960s, were found to be untenable as mechanisms of physiological action because of inappropriate experimental conditions. Several findings in the 1960s and 1970s, mainly 1) that near-physiological doses of T3 stimulated transcription measured in vivo or in nuclei isolated from tissues of rats and frog tadpoles, 2) the inhibition of hormone action by inhibitors of transcription and 3) the rapid and almost identical kinetics of accumulation of labelled hormone and RNA synthesis in target cell nuclei, pointed to the cell nucleus as a major site of its action. The application of technologies of recombinant DNA, gene cloning and DNA sequencing in the mid-1980s allowed the identification and understanding of the structure and function of nuclear receptors of TH. This review traces the road leading to the nuclear receptors of thyroid hormone, thus explaining how the hormone influences gene expression. It also illustrates the importance of how new concepts originate from the progression of technological innovations. This article is part of a Special Issue entitled Thyroid hormone signalling. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Effect of Oil Paint Fumes Inhalation on the Level of Serum Thyroid Hormones and Thyroid Stimulating Hormone in Rats

    Directory of Open Access Journals (Sweden)

    M. Siavashi

    2016-09-01

    Full Text Available Aims: The exposure to chemical materials and colors affects thyroid gland functions. The aim of this study was to investigate the effects of fume inhalation of oil-based paints on the serum level of thyroid hormones in female and male rats. Materials & Methods: In the experimental study, 15 male and 15 female Wistar rats were studied. The rats were divided into six 5-rat groups including a control group and groups with either 1- or 8-hour a day exposure to the paint fumes by gender division. The serum levels of T3, T4, and TSH thyroid hormones were measured after 10 weeks. Data was analyzed by SPSS 20 software using two-way ANOVA and Tukey’s post-hoc. Findings: Mean values of T3 and T4 hormones were significantly reduced in both 1- and 8-hour male and female groups than control group (p<0.001. In addition, the more the inhalation time, the more the reduction was. Any reduction in T3 in females in 1-hour (p<0.001 and 8–hour (p<0.05 groups was significantly more than the males. Nevertheless, a significant reduction in T4 was only in 1-hour group (p<0.001. Mean TSH hormone was significantly increased due to the inhalation of paint fume than control group (p<0.001. In addition, such an increase was significant in the female rats in 8-hour group than the male group (p<0.01. Conclusion: The inhalation of oil-based paint fume leads to a reduction in the serum levels of T3 and T4 thyroid hormones, while increases TSH serum level. Such an effect is stronger in the females.

  5. Genetic features of thyroid hormone receptors

    Indian Academy of Sciences (India)

    1995) and coronary heart disease (Goumidi et al. 2011b), and with response to drugs (Duan et al. 2012). The ... TRα1 is primarily expressed in heart, bone and brain, while TRβ1 is more abundant in liver, kidney and thy- ... stimulating hormone (TSH) level in healthy subjects (Lopez et al. 2008) and with Alzheimer's disease ...

  6. The menace of endocrine disruptors on thyroid hormone physiology and their impact on intrauterine development.

    Science.gov (United States)

    Mastorakos, George; Karoutsou, Eftychia I; Mizamtsidi, Maria; Creatsas, George

    2007-06-01

    The delivery of the appropriate thyroid hormones quantity to target tissues in euthyroidism is the result of unopposed synthesis, transport, metabolism, and excretion of these hormones. Thyroid hormones homeostasis depends on the maintenance of the circulating 'free' thyroid hormone reserves and on the development of a dynamic balance between the 'free' hormones reserves and those of the 'bound' hormones with the transport proteins. Disturbance of this hormone system, which is in constant interaction with other hormone systems, leads to an adaptational counter-response targeting to re-establish a new homeostatic equilibrium. An excessive disturbance is likely to result, however, in hypo- or hyper- thyroid clinical states. Endocrine disruptors are chemical substances forming part of 'natural' contaminating agents found in most ecosystems. There is abundant evidence that several key components of the thyroid hormones homeostasis are susceptible to the action of endocrine disruptors. These chemicals include some chlorinated organic compounds, polycyclic aromatic hydrocarbons, herbicides, and pharmaceutical agents. Intrauterine exposure to endocrine disruptors that either mimic or antagonize thyroid hormones can produce permanent developmental disorders in the structure and functioning of the brain, leading to behavioral changes. Steroid receptors are important determinants of the consequences of endocrine disruptors. Their interaction with thyroid hormones complicates the effect of endocrine disruptors. The aim of this review is to present the effect of endocrine disruptors on thyroid hormones physiology and their potential impact on intrauterine development.

  7. Development and validation of in vitro bioassays for thyroid hormone receptor mediated endocrine disruption

    NARCIS (Netherlands)

    Freitas, de J.

    2012-01-01

    Thyroid hormones regulate crucial processes in vertebrates such as reproduction, development and energy metabolism. Endocrine disruption via the thyroid hormone system is gaining more attention both from scientists and regulators, because of the increasing incidence of hormone-related cancers and

  8. [Repigmentation of gray hair after thyroid hormone treatment].

    Science.gov (United States)

    Redondo, P; Guzmán, M; Marquina, M; Pretel, M; Aguado, L; Lloret, P; Gorrochategui, A

    2007-11-01

    Darkening of gray and white hairs occurred in 2 patients with increased exogenous triiodothyronine (T3) due to treatment of myxedema coma in one case and iatrogenic hyperthyroidism in the other. We hypothesized that thyroid hormone may affect the homeostasis of hair follicles. To test our hypothesis and investigate the influence of thyroid hormone on the hair cycle, we used an in vivo murine model and an in vitro model based on culture of follicular units. We used the standard C57BL/6 murine model of the hair cycle. T3 (0.5 microg) dissolved in ethanol was applied topically once daily for 10 days to a depilated area in the telogen phase on the backs of the mice. Follicular units, obtained from hair transplant interventions, were cultured in vitro with different concentrations of T3. On day 5, all T3-treated mice entered the anagen phase, whereas the anagen phase started spontaneously in control mice on day 9, and not until day 15 had all controls entered this phase. In the in vitro experiment, follicular units treated with 100 nmol/L T3 grew significantly larger compared to the control group. These data suggest that follicles in the telogen phase can be induced to enter the anagen phase by the topical application of T3. This thyroid hormone may reverse graying of the terminal hair. In the in vitro experiments, T3 stimulated hair shaft growth. Follicular melanocytes may be the target cell for these actions.

  9. Neither bST nor Growth Hormone Releasing Factor Alter Expression of Thyroid Hormone Receptors in Liver and Mammary Tissues

    Science.gov (United States)

    Physiological effects of thyroid hormones are mediated primarily by binding of triiodothyronine, to specific nuclear receptors. It has been hypothesized that organ-specific changes in production of triiodothyronine from its prohormone, thyroxine, target the action of thyroid hormones to the mammary...

  10. Characterization of the hormone-binding domain of the chicken c-erbA/thyroid hormone receptor protein

    DEFF Research Database (Denmark)

    Muñoz, A; Zenke, M; Gehring, U

    1988-01-01

    To identify and characterize the hormone-binding domain of the thyroid hormone receptor, we analyzed the ligand-binding capacities of proteins representing chimeras between the normal receptor and P75gag-v-erbA, the retrovirus-encoded form deficient in binding ligand. Our results show that several...... mutations present in the carboxy-terminal half of P75gag-v-erbA co-operate in abolishing hormone binding, and that the ligand-binding domain resides in a position analogous to that of steroid receptors. Furthermore, a point mutation that is located between the putative DNA and ligand-binding domains of P75......gag-v-erbA and that renders it biologically inactive fails to affect hormone binding by the c-erbA protein. These results suggest that the mutation changed the ability of P75gag-v-erbA to affect transcription since it also had no effect on DNA binding. Our data also suggest that hormone...

  11. Thyroid function and stress hormones in children with stress hyperglycemia.

    Science.gov (United States)

    Bordbar, Mohammad Reza; Taj-Aldini, Reza; Karamizadeh, Zohre; Haghpanah, Sezaneh; Karimi, Mehran; Omrani, Gholam Hossein

    2012-12-01

    The purpose of the study is to determine the prevalence of stress hyperglycemia and to investigate how thyroid and stress hormones alter during stress hyperglycemia in children admitted to pediatric emergency wards. A prospective cross-sectional study was conducted in children, less than 19 years old, who were admitted to pediatric emergency wards of Nemazee and Dastgheib Hospitals, Shiraz, Southern Iran. Those patients taking steroids, beta-agonists or intravenously administered glucose before venipuncture, and patients with diabetes mellitus (DM) or thyroid diseases were excluded. Children with blood glucose ≥ 150 mg/dL during admission were regarded as cases. The controls were age- and- sex- matched, euglycemic children. Stress hormones including cortisol, insulin, growth hormone, and prolactin were measured, and thyroid function was tested with a radioimmunoassay (RIA) method in all cases and controls. The results showed that among 1,054 screened children, 39 cases (3.7 %) had stress hyperglycemia and 89 controls were included in the study. The occurrence of hyperglycemia was independent of sex, but it occurred mostly in children under 6 years old. Hyperglycemia occurred more frequently in patients with a positive family history of DM (odds ratio = 3.2, 95 % CI = 1.3-7.9, and P = 0.009). There were no significant differences between cases and controls regarding any hormones except higher cortisol, and lower total T3 and T4 in cases compared with controls. Neither of cases developed diabetes in the 24-month follow-up period. These findings led us to the conclusion that stress hyperglycemia is occasionally seen in critically ill patients. Among the stress hormones measured, only cortisol increased during hyperglycemia. It seems that hyperglycemia is not an important risk factor for future diabetes.

  12. Features of changes in concentration of pituitary thyroid hormone and thyroid hormones in the blood of two-month rats with experimental hypothyroidism before and after operations with N-(2-methoxybenzoyl)-O-isopropyl-α, β-dehydrothyrozine choline ester

    International Nuclear Information System (INIS)

    Khachatryan, T.S.; Topuzyan, V.O.

    2013-01-01

    The features of pituitary thyroid hormone concentration and thyroid hormones in the blood of rats with experimental hypothyroidism before and after injections of N-(2-methoxybenzoyl)-O-isopropyl-α, β-dehydrothyrozine choline ester were investigated. A sharp increase of pituitary thyroid hormone level and a sharp decrease of the level of thyroid hormones in the blood of two-month rats with hypothyroidism have been established. Under the action of N-(2-methoxybenzoyl)-O-isopropyl--α, β-dehydrothyrozine choline ester the decrease of pituitary thyroid hormone concentration and the increase of thyroid hormones level in the rats' blood have been observed and reached their values in intact animals

  13. Thyroid hormones association with depression severity and clinical outcome in patients with major depressive disorder

    OpenAIRE

    Berent, Dominika; Zboralski, Krzysztof; Orzechowska, Agata; Gałecki, Piotr

    2014-01-01

    The clinical implications of thyroid hormones in depression have been studied extensively and still remains disputable. Supplementation of thyroid hormones is considered to augment and accelerate antidepressant treatment. Studies on the role of thyroid hormones in depression deliver contradictory results. Here we assess theirs impact on depression severity and final clinical outcome in patients with major depression. Thyrotropin, free thyroxine (FT4), and free triiodothyronine (FT3) concentra...

  14. Recent Advances in Thyroid Hormone Regulation: Toward a New Paradigm for Optimal Diagnosis and Treatment

    OpenAIRE

    Rudolf Hoermann; John E. M. Midgley; Rolf Larisch; Johannes W. Dietrich; Johannes W. Dietrich; Johannes W. Dietrich

    2017-01-01

    In thyroid health, the pituitary hormone thyroid-stimulating hormone (TSH) raises glandular thyroid hormone production to a physiological level and enhances formation and conversion of T4 to the biologically more active T3. Overstimulation is limited by negative feedback control. In equilibrium defining the euthyroid state, the relationship between TSH and FT4 expresses clusters of genetically determined, interlocked TSH–FT4 pairs, which invalidates their statistical correlation within the eu...

  15. A method for the analysis of six thyroid hormones in thyroid gland by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Kunisue, Tatsuya; Fisher, Jeffrey W; Fatuyi, Babatope; Kannan, Kurunthachalam

    2010-07-01

    Perchlorate can competitively inhibit iodide uptake by the thyroid gland (TG) via the sodium/iodide symporter, consequently reducing the production of thyroid hormones (THs). Until recently, the effects of perchlorate on TH homeostasis are being examined through measurement of serum levels of TH, by immunoassay (IA)-based methods. IA methods are fast, but for TH analysis, they are compromised by the lack of adequate specificity. Therefore, selective and sensitive methods for the analysis of THs in TG are needed, for assessment of the effects of perchlorate on TH homeostasis. In this study, we developed a method for the analysis of six THs: L-thyroxine (T(4)), 3,3',5-triiodo-L-thyronine (T(3)), 3,3',5'-triiodo-L-thyronine (rT(3)), 3,5-diiodo-L-thyronine (3,5-T(2)), 3,3'-diiodo-L-thyronine (3,3'-T(2)), and 3-iodo-L-thyronine (3-T(1)) in TG, using liquid chromatography (LC)-tandem mass spectrometry (MS/MS). TGs used in this study were from rats that had been placed on either iodide-deficient diet or iodide-sufficient diet, and that had either been provided with perchlorate in drinking water (10 mg/kg/day) or control water. TGs were extracted by pronase digestion and then analyzed by LC-MS/MS. The instrumental calibration range for each TH ranged from 1 to 200 ng/ml and showed a high linearity (r>0.99). The method quantification limits (LOQs) were determined to be 0.25 ng/mg TG for 3-T(1); 0.33 ng/mg TG for 3,3'- and 3,5-T(2); and 0.52 ng/mg TG for rT(3), T(3), and T(4). Rats were placed on an iodide-deficient or -sufficient diet for 2.5 months, and for the last 2 weeks of that period were provided either perchlorate (10 mg/kg/day) in drinking water or control water. Iodide deficiency and perchlorate administration both reduced TG stores of rT(3), T(3), and T(4). In iodide-deficient rats, perchlorate exacerbated the reduction in levels of THs in TG. With the advances in analytical methodology, the use of LC-MS/MS for measurement of hormone levels in TG will allow more

  16. Pituitary transcription factors in the aetiology of combined pituitary hormone deficiency.

    Science.gov (United States)

    Pfäffle, R; Klammt, J

    2011-02-01

    The somatotropic axis is the central postnatal regulator of longitudinal growth. One of its major components--growth hormone--is produced by the anterior lobe of the pituitary, which also expresses and secretes five additional hormones (prolactin, thyroid stimulating hormone, follicle stimulating hormone, luteinizing hormone, adrenocorticotropic hormone). Proper development of the pituitary assures the regulation of critical processes such as metabolic control, puberty and reproduction, stress response and lactation. Ontogeny of the adenohypophysis is orchestrated by inputs from neighbouring tissues, cellular signalling molecules and transcription factors. Perturbation of expression or function of these factors has been implicated in the aetiology of combined pituitary hormone deficiency (CPHD). Mutations within the genes encoding for the transcription factors LHX3, LHX4, PROP1, and POU1F1 (PIT1) that act at different stages of pituitary development result in unique patterns of hormonal deficiencies reflecting their differential expression during organogenesis. In the case of LHX3 and LHX4 the phenotype may include extra-pituitary manifestations due to the function of these genes/proteins outside the pituitary gland. The remarkable variability in the clinical presentation of affected patients indicates the influence of the genetic background, environmental factors and possibly stochastic events. However, in the majority of CPHD cases the aetiology of this heterogeneous disease remains unexplained, which further suggests the involvement of additional genes. Identification of these factors might also help to close the gaps in our understanding of pituitary development, maintenance and function. Copyright © 2010 Elsevier Ltd. All rights reserved.

  17. Thyroid-Stimulating Hormone Receptor Antibodies in Pregnancy: Clinical Relevance

    Science.gov (United States)

    Bucci, Ines; Giuliani, Cesidio; Napolitano, Giorgio

    2017-01-01

    Graves’ disease is the most common cause of thyrotoxicosis in women of childbearing age. Approximately 1% of pregnant women been treated before, or are being treated during pregnancy for Graves’ hyperthyroidism. In pregnancy, as in not pregnant state, thyroid-stimulating hormone (TSH) receptor (TSHR) antibodies (TRAbs) are the pathogenetic hallmark of Graves’ disease. TRAbs are heterogeneous for molecular and functional properties and are subdivided into activating (TSAbs), blocking (TBAbs), or neutral (N-TRAbs) depending on their effect on TSHR. The typical clinical features of Graves’ disease (goiter, hyperthyroidism, ophthalmopathy, dermopathy) occur when TSAbs predominate. Graves’ disease shows some peculiarities in pregnancy. The TRAbs disturb the maternal as well as the fetal thyroid function given their ability to cross the placental barrier. The pregnancy-related immunosuppression reduces the levels of TRAbs in most cases although they persist in women with active disease as well as in women who received definitive therapy (radioiodine or surgery) before pregnancy. Changes of functional properties from stimulating to blocking the TSHR could occur during gestation. Drug therapy is the treatment of choice for hyperthyroidism during gestation. Antithyroid drugs also cross the placenta and therefore decrease both the maternal and the fetal thyroid hormone production. The management of Graves’ disease in pregnancy should be aimed at maintaining euthyroidism in the mother as well as in the fetus. Maternal and fetal thyroid dysfunction (hyperthyroidism as well as hypothyroidism) are in fact associated with several morbidities. Monitoring of the maternal thyroid function, TRAbs measurement, and fetal surveillance are the mainstay for the management of Graves’ disease in pregnancy. This review summarizes the biochemical, immunological, and therapeutic aspects of Graves’ disease in pregnancy focusing on the role of the TRAbs in maternal and fetal

  18. Iodine and thyroid gland with or without nuclear catastrophe

    OpenAIRE

    Kovačev-Zavišić Branka; Novaković-Paro Jovanka; Ičin Tijana; Bajkin Ivana; Todorović-Đilas Ljiljana

    2012-01-01

    Introduction. Iodine, as a trace element, is a necessary and limiting substrate for thyroid gland hormone synthesis. It is an essential element that enables the thyroid gland to produce thyroid hormones thyroxine (T4) and triiodothyronine (T3). Synthesis of Thyroid Hormones and Iodine Metabolism. Three iodine molecules are added to make triiodothyronine, and four for thyroxine - the two key hormones produced by the thyroid gland. Iodine deficiency. The proper daily amount of iodine is r...

  19. Doc Title: Adult Hippocampal Neurogenesis is Impaired by Transient Developmental Thyroid Hormone Disruption

    Data.gov (United States)

    U.S. Environmental Protection Agency — Severe thyroid hormone (TH) deprivation during development impairs neurogenesis throughout the brain. The hippocampus also maintains a capacity for neurogenesis...

  20. Increased oxidative metabolism and neurotransmitter cycling in the brain of mice lacking the thyroid hormone transporter SLC16A2 (MCT8).

    Science.gov (United States)

    Rodrigues, Tiago B; Ceballos, Ainhoa; Grijota-Martínez, Carmen; Nuñez, Barbara; Refetoff, Samuel; Cerdán, Sebastian; Morte, Beatriz; Bernal, Juan

    2013-01-01

    Mutations of the monocarboxylate transporter 8 (MCT8) cause a severe X-linked intellectual deficit and neurological impairment. MCT8 is a specific thyroid hormone (T4 and T3) transporter and the patients also present unusual abnormalities in the serum profile of thyroid hormone concentrations due to altered secretion and metabolism of T4 and T3. Given the role of thyroid hormones in brain development, it is thought that the neurological impairment is due to restricted transport of thyroid hormones to the target neurons. In this work we have investigated cerebral metabolism in mice with Mct8 deficiency. Adult male mice were infused for 30 minutes with (1-(13)C) glucose and brain extracts prepared and analyzed by (13)C nuclear magnetic resonance spectroscopy. Genetic inactivation of Mct8 resulted in increased oxidative metabolism as reflected by increased glutamate C4 enrichment, and of glutamatergic and GABAergic neurotransmissions as observed by the increases in glutamine C4 and GABA C2 enrichments, respectively. These changes were distinct to those produced by hypothyroidism or hyperthyroidism. Similar increments in glutamate C4 enrichment and GABAergic neurotransmission were observed in the combined inactivation of Mct8 and D2, indicating that the increased neurotransmission and metabolic activity were not due to increased production of cerebral T3 by the D2-encoded type 2 deiodinase. In conclusion, Mct8 deficiency has important metabolic consequences in the brain that could not be correlated with deficiency or excess of thyroid hormone supply to the brain during adulthood.

  1. Thyroid storm due to inappropriate administration of a compounded thyroid hormone preparation successfully treated with plasmapheresis.

    Science.gov (United States)

    Jha, Sujeet; Waghdhare, Swati; Reddi, Rajashekar; Bhattacharya, Priyanka

    2012-12-01

    a life-saving treatment in patients who are exposed to amounts of thyroid hormone far in excess of that usually produced by the thyroid gland.

  2. The role of thyroid hormones in regulating of fatty acid spectrum of brain lipids: ontogenetic aspect

    Directory of Open Access Journals (Sweden)

    Rodynskiy A.G.

    2016-05-01

    Full Text Available In experiments on rats of three age groups the role of thyroid hormones in the regulation of fatty acid spectrum of cortical and hippocampus lipids was studied. It was found that on the background of decreased thyroid status content of polyunsaturated fractions of free fatty acids, significantly changed depending on the age of the animals. In particular, in juvenile rats hypothyroidism was accompanied by a decrease almost twice the number of pentacodan acid decreased lipids viscosity in neurocortex. In old rats reduce of pentacodan acid in the cortex (38% was supplemented by significant (77% decrease in linoleic and linolenic acids. Unlike the two age groups deficiency of thyroid hormones in young animals caused accumulation of free polyunsatarated fatty acids (C18: 2.3 in the cerebral cortex by 74%, which may be associated with a decrease of this fraction in fatty acid spectrum of lipids and increase of viscosity properties of the membranes. These restruc­turing may be associated with modulation of synaptic transmission of specific neurotransmitter systems in the brain.

  3. Thyroid-stimulating hormone, anti-thyroid antibodies, and pregnancy outcomes.

    Science.gov (United States)

    Plowden, Torie C; Schisterman, Enrique F; Sjaarda, Lindsey A; Perkins, Neil J; Silver, Robert; Radin, Rose; Kim, Keewan; Galai, Noya; DeCherney, Alan H; Mumford, Sunni L

    2017-12-01

    Overt thyroid dysfunction has been associated with adverse obstetric outcomes. However, less is known regarding subclinical hypothyroidism or thyroid autoimmunity and their relationship to pregnancy complications. The purpose of this study was to examine the association between prepregnancy anti-thyroid antibodies and subclinical hypothyroidism and preterm delivery, gestational diabetes mellitus, and preeclampsia. We conducted a secondary analysis of a prospective cohort of 18- to 40-year-old women with 1-2 previous pregnancy losses (n=1193) who participated in a multicenter randomized, placebo-controlled trial of low-dose aspirin. Prepregnancy levels of thyroid-stimulating hormone, free thyroxine, thyroglobulin antibody, and thyroid peroxidase antibody were measured. Relative risks and 95% confidence intervals were estimated with the use of generalized linear models with adjustment for age and body mass index. Among women with an ongoing pregnancy of >20 weeks estimated gestational age, there was no association between prepregnancy thyroid-stimulating hormone level (>2.5 vs ≤2.5 mIU/L) and preterm delivery (adjusted relative risk, 0.77; 95% confidence interval, 0.40-1.47), gestational diabetes mellitus (adjusted relative risk, 1.28; 95% confidence interval, 0.54-3.04), or preeclampsia (adjusted relative risk, 1.20; 95% confidence interval, 0.71-2.04). Similarly, among women with thyroid antibodies, there was no increase in the likelihood of preterm delivery (relative risk, 1.26; 95% confidence interval, 0.65-2.45), gestational diabetes mellitus (relative risk, 1.33; 95% confidence interval, 0.51-3.49), or preeclampsia (relative risk, 1.02; 95% confidence interval, 0.54-1.92), compared with women without these antibodies. Among women with 1-2 previous pregnancy losses, subclinical hypothyroidism and thyroid autoimmunity were not associated with an increased risk of preterm delivery, gestational diabetes mellitus, or preeclampsia. These data support current

  4. Melatonin in the thyroid gland: regulation by thyroid-stimulating hormone and role in thyroglobulin gene expression.

    Science.gov (United States)

    Garcia-Marin, R; Fernandez-Santos, J M; Morillo-Bernal, J; Gordillo-Martinez, F; Vazquez-Roman, V; Utrilla, J C; Carrillo-Vico, A; Guerrero, J M; Martin-Lacave, I

    2015-10-01

    Melatonin is an indoleamine with multiple functions in both plant and animal species. In addition to data in literature describing many other important roles for melatonin, such as antioxidant, circadian rhythm controlling, anti-aging, antiproliferative or immunomodulatory activities, our group recently reported that thyroid C-cells synthesize melatonin and suggested a paracrine role for this molecule in the regulation of thyroid activity. To discern the role played by melatonin at thyroid level and its involvement in the hypothalamic-pituitary-thyroid axis, in the present study we have analyzed the effect of thyrotropin in the regulation of the enzymatic machinery for melatonin biosynthesis in C cells as well as the effect of melatonin in the regulation of thyroid hormone biosynthesis in thyrocytes. Our results show that the key enzymes for melatonin biosynthesis (AANAT and ASMT) are regulated by thyroid-stimulating hormone. Furthermore, exogenous melatonin increases thyroglobulin expression at mRNA and protein levels on cultured thyrocytes and this effect is not strictly mediated by the upregulation of TTF1 or, noteworthy, PAX8 transcription factors. The present data show that thyroid C-cells synthesize melatonin under thyroid-stimulating hormone control and, consistently with previous data, support the hypothesis of a paracrine role for C-cell-synthesised melatonin within the thyroid gland. Additionally, in the present study we show evidence for the involvement of melatonin in thyroid function by directly-regulating thyroglobulin gene expression in follicular cells.

  5. An Evo-Devo Approach to Thyroid Hormones in Cerebral and Cerebellar Cortical Development: Etiological Implications for Autism

    Science.gov (United States)

    Berbel, Pere; Navarro, Daniela; Román, Gustavo C.

    2014-01-01

    The morphological alterations of cortical lamination observed in mouse models of developmental hypothyroidism prompted the recognition that these experimental changes resembled the brain lesions of children with autism; this led to recent studies showing that maternal thyroid hormone deficiency increases fourfold the risk of autism spectrum disorders (ASD), offering for the first time the possibility of prevention of some forms of ASD. For ethical reasons, the role of thyroid hormones on brain development is currently studied using animal models, usually mice and rats. Although mammals have in common many basic developmental principles regulating brain development, as well as fundamental basic mechanisms that are controlled by similar metabolic pathway activated genes, there are also important differences. For instance, the rodent cerebral cortex is basically a primary cortex, whereas the primary sensory areas in humans account for a very small surface in the cerebral cortex when compared to the associative and frontal areas that are more extensive. Associative and frontal areas in humans are involved in many neurological disorders, including ASD, attention deficit-hyperactive disorder, and dyslexia, among others. Therefore, an evo-devo approach to neocortical evolution among species is fundamental to understand not only the role of thyroid hormones and environmental thyroid disruptors on evolution, development, and organization of the cerebral cortex in mammals but also their role in neurological diseases associated to thyroid dysfunction. PMID:25250016

  6. Targeting the thyroid gland with thyroid-stimulating hormone (TSH)-nanoliposomes.

    Science.gov (United States)

    Paolino, Donatella; Cosco, Donato; Gaspari, Marco; Celano, Marilena; Wolfram, Joy; Voce, Pasquale; Puxeddu, Efisio; Filetti, Sebastiano; Celia, Christian; Ferrari, Mauro; Russo, Diego; Fresta, Massimo

    2014-08-01

    Various tissue-specific antibodies have been attached to nanoparticles to obtain targeted delivery. In particular, nanodelivery systems with selectivity for breast, prostate and cancer tissue have been developed. Here, we have developed a nanodelivery system that targets the thyroid gland. Nanoliposomes have been conjugated to the thyroid-stimulating hormone (TSH), which binds to the TSH receptor (TSHr) on the surface of thyrocytes. The results indicate that the intracellular uptake of TSH-nanoliposomes is increased in cells expressing the TSHr. The accumulation of targeted nanoliposomes in the thyroid gland following intravenous injection was 3.5-fold higher in comparison to untargeted nanoliposomes. Furthermore, TSH-nanoliposomes encapsulated with gemcitabine showed improved anticancer efficacy in vitro and in a tumor model of follicular thyroid carcinoma. This drug delivery system could be used for the treatment of a broad spectrum of thyroid diseases to reduce side effects and improve therapeutic efficacy. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Methylation of the thyroid stimulating hormone receptor: diagnostic marker of malignity in thyroid cancer

    International Nuclear Information System (INIS)

    Marrero Rodriguez, Maria Teresa

    2007-01-01

    The methylation state of the gene promoter for the receptor of the thyroid stimulating hormone (TSH) in the diagnosis of thyroid tumors of epithelial origin was analyzed. The study was conducted in thyroid tissue obtained from paraffin blocks of different thyroid pathologies (papillary, follicular and undifferentiated carcinoma and follicular adenomas). The work was done by using the DNA modification technique with sodium bisulfite, and polymerase chain reaction was applied to analyze the gene methylation state. Methylation of the promoter for the gene of the TSH receptor was found in the papillary carcinomas (33 of 40; 82.5 %), in 10 undifferentiated carcinomas (100 %), and in 10 of the 15 follicular carcinomas analyzed (66.6 %). No methylation was observed in the 8 follicular adenomas under study. The methylation of the gene for the TSH receptor was proposed as a new diagnostic marker of malignity and as a basis for using demethylating agents together with radioiodine therapy in patients with thyroid cancer of epithelial origin that do not respond to therapy. (Author)

  8. Levothyroxine dosage is associated with stability of thyroid-stimulating hormone values.

    Science.gov (United States)

    Pecina, Jennifer; Garrison, Gregory M; Bernard, Matthew E

    2014-03-01

    In patients treated for hypothyroidism, the usual practice is to monitor thyroid-stimulating hormone values yearly once a therapeutic dosage of levothyroxine is determined. This study investigates whether there are any clinical predictors that could identify a subset of patients who might be monitored safely on a less frequent basis. With the use of a retrospective study design, 715 patients treated for hypothyroidism who had a normal (ie, therapeutic) thyroid-stimulating hormone value in 2006 while taking levothyroxine were identified. All thyroid-stimulating hormone values were then obtained through December 31, 2012. By using a Cox proportional hazard model, gender, age, body mass index, history of chronic autoimmune thyroiditis, initial thyroid-stimulating hormone level, and levothyroxine dose were analyzed for time to first abnormal thyroid-stimulating hormone value. Age, gender, history of chronic autoimmune thyroiditis, and body mass index at the time of initial normal thyroid-stimulating hormone were not associated significantly with time to abnormal thyroid-stimulating hormone value. Levothyroxine dose >125 μg/day had an increased hazard ratio of 2.4 (95% confidence interval, 1.7-3.4; P 125 μg/day did. Transformed thyroid-stimulating hormone value (which represents a measure of how far the initial thyroid-stimulating hormone was from the midpoint of the normal range) also had an increased hazard ratio of 1.14 (95% confidence interval, 1.1-1.2; P levothyroxine, we propose that a testing interval up to 2 years may be acceptable if their thyroid-stimulating hormone is well within the normal range. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Assessment of thyroid hormones, insulin and magnesium in dairy cattle with subclinical ketosis

    Directory of Open Access Journals (Sweden)

    A Sadeghi-nasab

    2011-08-01

    Full Text Available Ketosis, with ethologically energy deficiency, is one of the commonest metabolic diseases of dairy cattle. Assessment of some serum hormonal and metabolic status can be beneficent in prediction and diagnosis of subclinical ketosis. This study is performed for evaluation and comparison of thyroid hormones, insulin and magnesium of subclinical ketosis and healthy cows. During 60 days in milk (DIM serum Beta hydroxy butyric acid (BHBA and glucose levels of 200 dairy cattle have been measured. Based on 1.4 mmol/l of BHBA as a cut of point experimented animals separated to subclinical and healthy groups. Mean values of serum T3 and T4 of affected cows were significantly higher than non-affected (p

  10. Thyroid Hormone Role and Economy in the Developing Testis.

    Science.gov (United States)

    Hernandez, Arturo

    2018-01-01

    Thyroid hormones (TH) exhibit pleiotropic regulatory effects on growth, development, and metabolism, and it is becoming increasingly apparent that the developing testis is an important target for them. Testicular development is highly dependent on TH status. Both hypo- and hyperthyroidism affect testis size and the proliferation and differentiation of Sertoli, Leydig, and germ cells, with consequences for steroidogenesis, spermatogenesis, and male fertility. These observations suggest that an appropriate content of TH and by implication TH action in the testis, whether the result of systemic hormonal levels or regulatory mechanisms at the local level, is critical for normal testicular and reproductive function. The available evidence indicates the presence in the developing testis of a number of transporters, deiodinases and receptors that could play a role in the timely delivery of TH action on testicular cells. These include the thyroid hormone receptor alpha (THRA), the MCT8 transporter, the TH-activating deiodinase DIO2, and the TH-inactivating deiodinase DIO3, all of which appear to modulate testicular TH economy and testis outcomes. © 2018 Elsevier Inc. All rights reserved.

  11. Thyroid hormone receptors control developmental maturation of the middle ear and the size of the ossicular bones.

    Science.gov (United States)

    Cordas, Emily A; Ng, Lily; Hernandez, Arturo; Kaneshige, Masahiro; Cheng, Sheue-Yann; Forrest, Douglas

    2012-03-01

    Thyroid hormone is critical for auditory development and has well-known actions in the inner ear. However, less is known of thyroid hormone functions in the middle ear, which contains the ossicles (malleus, incus, stapes) that relay mechanical sound vibrations from the outer ear to the inner ear. During the later stages of middle ear development, prior to the onset of hearing, middle ear cavitation occurs, involving clearance of mesenchyme from the middle ear cavity while the immature cartilaginous ossicles attain appropriate size and ossify. Using in situ hybridization, we detected expression of Thra and Thrb genes encoding thyroid hormone receptors α1 and β (TRα1 and TRβ, respectively) in the immature ossicles, surrounding mesenchyme and tympanic membrane in the mouse. Thra(+/PV) mice that express a dominant-negative TRα1 protein exhibited deafness with elevated auditory thresholds and a range of middle ear abnormalities including chronic persistence of mesenchyme in the middle ear into adulthood, markedly enlarged ossicles, and delayed ossification of the ossicles. Congenitally hypothyroid Tshr(-/-) mice and TR-deficient Thra1(-/-);Thrb(-/-) mice displayed similar abnormalities. These findings demonstrate that middle ear maturation is TR dependent and suggest that the middle ear is a sensitive target for thyroid hormone in development.

  12. Nitric oxide and thyroid hormone receptor alpha 1 contribute to ovarian follicular development in immature hyper- and hypo-thyroid rats.

    Science.gov (United States)

    Zheng, Kaizhi; Sulieman, Fedail Jaafar; Li, Junrong; Wei, Quanwei; Xu, Mulin; Shi, Fangxiong

    2015-03-01

    Thyroid dysfunction can cause ovarian cycle and ovulatory disturbances, however, the molecular link(s) between these two disorders remains largely unknown. In the current study, we examined the roles of nitric oxide synthase (NOS) and thyroid hormone receptor alpha 1 (TRα1) in these disorders using immature hyper-thyroid (hyper-T) and hypo-thyroid (hypo-T) rats. In comparison to controls, hyper-T rats had higher serum concentrations of triiodothyronine (T3) and thyroxine (T4), whereas hypo-T rats had lower serum T3 and T4. Serum estradiol (E2) level was decreased in both hyper-T and hypo-T animals and serum E2 in hyper-T rats were lower than in hypo-T rats. We found that neuronal NOS (nNOS) and TRα1 were present in oocytes, granulosa cells and theca cells of all examined rat groups. Ovarian nitric oxide (NO) content and the constitutive NOS (cNOS) activity in hyper-T rats were significantly decreased compared with control or hypo-T rats. Moreover, the number of large antral follicles was reduced in hyper-T rats, and number of primordial follicles was decreased in hypo-T rats compared with control rats. In conclusion, we observed an association between thyroid hormone and NO signaling pathways during the process of ovarian follicular development in immature rats. In hyperthyroidism, thyroid hormones induced an estrogen deficiency that inhibited the function of nNOS, resulting in the inhibition of NO synthesis and suppressed development of large antral follicles, while in hypothyroidism only development of primordial follicles was inhibited. Copyright © 2014 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  13. Psychomotor retardation in a girl with complete growth hormone deficiency.

    Science.gov (United States)

    Dayal, Devi; Malhi, Prabhjot; Kumar Bhalla, Anil; Sachdeva, Naresh; Kumar, Rakesh

    2013-01-01

    Infants with complete growth hormone deficiency may suffer from psychomotor retardation in addition to severe growth failure. Without replacement therapy, they may have a compromised intellectual potential manifesting as learning disabilities and attention-deficit disorders in later life. In this communication, we discuss an infant who showed improvement in physical growth after growth hormone therapy but her psychomotor skills did not improve probably due to late start of treatment. There is a need to start growth hormone therapy as early as possible in infants with complete growth hormone deficiency to avoid adverse effects on psychomotor and brain development.

  14. Thyroid organotypic rat and human cultures used to investigate drug effects on thyroid function, hormone synthesis and release pathways

    Energy Technology Data Exchange (ETDEWEB)

    Vickers, Alison E.M., E-mail: vickers_alison@allergan.com [Drug Safety Evaluation, Allergan Inc., 2525 Dupont Dr, Irvine CA 92612 (United States); Heale, Jason; Sinclair, John R.; Morris, Stephen; Rowe, Josh M. [Drug Safety Evaluation, Allergan Inc., 2525 Dupont Dr, Irvine CA 92612 (United States); Fisher, Robyn L. [Vitron Inc., Tucson, AZ (United States)

    2012-04-01

    Drug induced thyroid effects were evaluated in organotypic models utilizing either a rat thyroid lobe or human thyroid slices to compare rodent and human response. An inhibition of thyroid peroxidase (TPO) function led to a perturbation in the expression of key genes in thyroid hormone synthesis and release pathways. The clinically used thiourea drugs, methimazole (MMI) and 6-n-propyl-2-thioruacil (PTU), were used to evaluate thyroid drug response in these models. Inhibition of TPO occurred early as shown in rat thyroid lobes (2 h) and was sustained in both rat (24–48 h) and human (24 h) with ≥ 10 μM MMI. Thyroid from rats treated with single doses of MMI (30–1000 mg/kg) exhibited sustained TPO inhibition at 48 h. The MMI in vivo thyroid concentrations were comparable to the culture concentrations (∼ 15–84 μM), thus demonstrating a close correlation between in vivo and ex vivo thyroid effects. A compensatory response to TPO inhibition was demonstrated in the rat thyroid lobe with significant up-regulation of genes involved in the pathway of thyroid hormone synthesis (Tpo, Dio1, Slc5a5, Tg, Tshr) and the megalin release pathway (Lrp2) by 24 h with MMI (≥ 10 μM) and PTU (100 μM). Similarly, thyroid from the rat in vivo study exhibited an up-regulation of Dio1, Slc5a5, Lrp2, and Tshr. In human thyroid slices, there were few gene expression changes (Slc5a5, ∼ 2-fold) and only at higher MMI concentrations (≥ 1500 μM, 24 h). Extended exposure (48 h) resulted in up-regulation of Tpo, Dio1 and Lrp2, along with Slc5a5 and Tshr. In summary, TPO was inhibited by similar MMI concentrations in rat and human tissue, however an increased sensitivity to drug treatment in rat is indicated by the up-regulation of thyroid hormone synthesis and release gene pathways at concentrations found not to affect human tissue. -- Highlights: ► Novel model of rat thyroid or human thyroid slices to evaluate pathways of injury. ► TPO inhibition by MMI or PTU altered

  15. Thyroid organotypic rat and human cultures used to investigate drug effects on thyroid function, hormone synthesis and release pathways

    International Nuclear Information System (INIS)

    Vickers, Alison E.M.; Heale, Jason; Sinclair, John R.; Morris, Stephen; Rowe, Josh M.; Fisher, Robyn L.

    2012-01-01

    Drug induced thyroid effects were evaluated in organotypic models utilizing either a rat thyroid lobe or human thyroid slices to compare rodent and human response. An inhibition of thyroid peroxidase (TPO) function led to a perturbation in the expression of key genes in thyroid hormone synthesis and release pathways. The clinically used thiourea drugs, methimazole (MMI) and 6-n-propyl-2-thioruacil (PTU), were used to evaluate thyroid drug response in these models. Inhibition of TPO occurred early as shown in rat thyroid lobes (2 h) and was sustained in both rat (24–48 h) and human (24 h) with ≥ 10 μM MMI. Thyroid from rats treated with single doses of MMI (30–1000 mg/kg) exhibited sustained TPO inhibition at 48 h. The MMI in vivo thyroid concentrations were comparable to the culture concentrations (∼ 15–84 μM), thus demonstrating a close correlation between in vivo and ex vivo thyroid effects. A compensatory response to TPO inhibition was demonstrated in the rat thyroid lobe with significant up-regulation of genes involved in the pathway of thyroid hormone synthesis (Tpo, Dio1, Slc5a5, Tg, Tshr) and the megalin release pathway (Lrp2) by 24 h with MMI (≥ 10 μM) and PTU (100 μM). Similarly, thyroid from the rat in vivo study exhibited an up-regulation of Dio1, Slc5a5, Lrp2, and Tshr. In human thyroid slices, there were few gene expression changes (Slc5a5, ∼ 2-fold) and only at higher MMI concentrations (≥ 1500 μM, 24 h). Extended exposure (48 h) resulted in up-regulation of Tpo, Dio1 and Lrp2, along with Slc5a5 and Tshr. In summary, TPO was inhibited by similar MMI concentrations in rat and human tissue, however an increased sensitivity to drug treatment in rat is indicated by the up-regulation of thyroid hormone synthesis and release gene pathways at concentrations found not to affect human tissue. -- Highlights: ► Novel model of rat thyroid or human thyroid slices to evaluate pathways of injury. ► TPO inhibition by MMI or PTU altered

  16. Nuclear Import and Export of the Thyroid Hormone Receptor.

    Science.gov (United States)

    Zhang, Jibo; Roggero, Vincent R; Allison, Lizabeth A

    2018-01-01

    The thyroid hormone receptors, TRα1 and TRβ1, are members of the nuclear receptor superfamily that forms one of the most abundant classes of transcription factors in multicellular organisms. Although primarily localized to the nucleus, TRα1 and TRβ1 shuttle rapidly between the nucleus and cytoplasm. The fine balance between nuclear import and export of TRs has emerged as a critical control point for modulating thyroid hormone-responsive gene expression. Mutagenesis studies have defined two nuclear localization signal (NLS) motifs that direct nuclear import of TRα1: NLS-1 in the hinge domain and NLS-2 in the N-terminal A/B domain. Three nuclear export signal (NES) motifs reside in the ligand-binding domain. A combined approach of shRNA-mediated knockdown and coimmunoprecipitation assays revealed that nuclear entry of TRα1 is facilitated by importin 7, likely through interactions with NLS-2, and importin β1 and the adapter importin α1 interacting with both NLS-1 and NLS-2. Interestingly, TRβ1 lacks NLS-2 and nuclear import depends solely on the importin α1/β1 heterodimer. Heterokaryon and fluorescence recovery after photobleaching shuttling assays identified multiple exportins that play a role in nuclear export of TRα1, including CRM1 (exportin 1), and exportins 4, 5, and 7. Even single amino acid changes in TRs dramatically alter their intracellular distribution patterns. We conclude that mutations within NLS and NES motifs affect nuclear shuttling activity, and propose that TR mislocalization contributes to the development of some types of cancer and Resistance to Thyroid Hormone syndrome. © 2018 Elsevier Inc. All rights reserved.

  17. Establishment of a serum thyroid stimulating hormone (TSH) reference interval in healthy adults

    DEFF Research Database (Denmark)

    Jensen, Esther; Hyltoft Petersen, Per; Blaabjerg, Ole

    2004-01-01

    It has previously been shown that thyroid antibodies affect thyroid stimulating hormone (TSH) concentrations in men and women and that TSH levels are predictive of future thyroid disease. We investigated the validity of the National Academy of Clinical Biochemistry (NACB) guidelines regarding...

  18. A Case of Resistance to Thyroid Hormone with Chronic Thyroiditis: Discovery of a Novel Mutation (I54V

    Directory of Open Access Journals (Sweden)

    I. Kammoun

    2011-01-01

    Full Text Available Resistance to thyroid hormone (RTH is a rare disorder characterized by variable tissue hyporesponsiveness to thyroid hormone, usually caused by mutations in the thyroid hormone receptor beta (TRβ. It has been reported that the serum of patients with RTH is free of auto-antibodies against thyroglobulin (Tg and thyroid peroxidase (TPO, except in rare cases where coincidental autoimmune thyroiditis is also present. We describe a 13-year-old girl with chronic thyroiditis and RTH. This patient had increased plasma free T3, free T4 at the upper limits with unsuppressed TSH. She had peripheral manifestations of thyroid hormone excess, hypertension and growth acceleration. Anti-TPO antibodies were positive. Sequence analysis of the TRβ gene was performed and revealed a novel mutation I54V in exon 4. The same mutation was also found in the mother and two asymptomatic sisters. The clinical presentation of our patient is not habitual in RTH because growth retardation is frequently reported in this syndrome. The association between RTH and thyroiditis complicate the management of the hypothyroidism.

  19. Analysis of thyroid hormones in biological samples using stable isotope dilution liquid chromatography-tandem mass spectrometry

    Science.gov (United States)

    This poster presentation will describe analytical chemistry methods for measuring thyroid hormones and related precursors and metabolites in very small tissue or plasma samples. These methods are amenable to measure thyroid hormones in amphibian tadpoles or small mammals used as ...

  20. Gender-specific regulation of response to thyroid hormone in aging

    Directory of Open Access Journals (Sweden)

    Suzuki Satoru

    2012-01-01

    Full Text Available Abstract Background Similar to other systems, the endocrine system is affected by aging. Thyroid hormone, the action of which is affected by many factors, has been shown to be associated with longevity. The most useful marker for the assessment of thyroid hormone action is TSH level. Although age and gender are believed to modify the pituitary set point or response to free thyroid hormone concentration, the precise age- and gender-dependent responses to thyroid hormone have yet to be reported. Methods We analyzed the results of 3564 thyroid function tests obtained from patients who received medication at both out- and inpatient clinics of Shinshu University Hospital. Subjects were from among those with thyroid function test results in the normal or mildly abnormal range. Based on a log-linear relationship between the concentrations of FHs and TSH, we established the putative resistance index to assess the relation between serum FH and TSH levels. Results Free thyroid hormone and TSH concentration showed an inverse log-linear relation. In males, there was a negative relationship between the free T3 resistance index and age. In females, although there were no relationships between age and FHs, the indices were positively related to age. Conclusions These findings indicated that there is a gender-specific response to thyroid hormone with aging. Although the TSH level is a useful marker for the assessment of peripheral thyroid hormone action, the values should be interpreted carefully, especially with regard to age- and gender-related differences.

  1. Human amniotic fluid contaminants alter thyroid hormone signalling and early brain development in Xenopus embryos

    Science.gov (United States)

    Fini, Jean-Baptiste; Mughal, Bilal B.; Le Mével, Sébastien; Leemans, Michelle; Lettmann, Mélodie; Spirhanzlova, Petra; Affaticati, Pierre; Jenett, Arnim; Demeneix, Barbara A.

    2017-03-01

    Thyroid hormones are essential for normal brain development in vertebrates. In humans, abnormal maternal thyroid hormone levels during early pregnancy are associated with decreased offspring IQ and modified brain structure. As numerous environmental chemicals disrupt thyroid hormone signalling, we questioned whether exposure to ubiquitous chemicals affects thyroid hormone responses during early neurogenesis. We established a mixture of 15 common chemicals at concentrations reported in human amniotic fluid. An in vivo larval reporter (GFP) assay served to determine integrated thyroid hormone transcriptional responses. Dose-dependent effects of short-term (72 h) exposure to single chemicals and the mixture were found. qPCR on dissected brains showed significant changes in thyroid hormone-related genes including receptors, deiodinases and neural differentiation markers. Further, exposure to mixture also modified neural proliferation as well as neuron and oligodendrocyte size. Finally, exposed tadpoles showed behavioural responses with dose-dependent reductions in mobility. In conclusion, exposure to a mixture of ubiquitous chemicals at concentrations found in human amniotic fluid affect thyroid hormone-dependent transcription, gene expression, brain development and behaviour in early embryogenesis. As thyroid hormone signalling is strongly conserved across vertebrates the results suggest that ubiquitous chemical mixtures could be exerting adverse effects on foetal human brain development.

  2. Prenatal and Neonatal Thyroid Stimulating Hormone Levels and Autism Spectrum Disorders

    Science.gov (United States)

    Yau, Vincent M.; Lutsky, Marta; Yoshida, Cathleen K.; Lasley, Bill; Kharrazi, Martin; Windham, Gayle; Gee, Nancy; Croen, Lisa A.

    2015-01-01

    Thyroid hormones are critical for normal brain development. This study examined autism spectrum disorders (ASD) and thyroid stimulating hormone (TSH) levels measured in mid-pregnancy maternal serum and infant blood after birth. Three groups of children born in Orange County, CA in 2000-2001 were identified: ASD (n = 78), developmental delay…

  3. Iodothyronine Deiodinases: structure-function analysis and their role in the regulation of thyroid hormone levels

    NARCIS (Netherlands)

    F.W.J.S. Wassen (Frank)

    2005-01-01

    textabstractThyroid hormone is important for energy metabolism, the metabolism of nutrients, inorganic ion fluxes and thermogenesis. Thyroid hormone is also essential for stimulation of growth and development of various tissues at critical periods including the central nervous system. Whereas in

  4. Detection of thyroid hormone receptor disruptors by a novel stable in vitro reporter gene assay

    NARCIS (Netherlands)

    Freitas, de J.; Cano, P.; Craig-Veit, C.; Goodson, M.L.; Furlow, J.D.; Murk, A.J.

    2011-01-01

    A stable luciferase reporter gene assay was developed based on the thyroid hormone responsive rat pituitary tumor GH3 cell line that constitutively expresses both thyroid hormone receptor isoforms. Stable transfection of the pGL4CP-SV40-2xtaDR4 construct into the GH3 cells resulted in a highly

  5. Effects of acute and chronic interleukin-6 administration on thyroid hormone metabolism in humans

    NARCIS (Netherlands)

    Stouthard, J. M.; van der Poll, T.; Endert, E.; Bakker, P. J.; Veenhof, C. H.; Sauerwein, H. P.; Romijn, J. A.

    1994-01-01

    Cytokines, such as tumor necrosis factor-alpha and interleukin-1 beta (IL-1 beta), alter thyroid hormone metabolism, and may be involved in the pathogenesis of the euthyroid sick syndrome. Both cytokines also induce the production of IL-6. To assess whether IL-6 itself modulates thyroid hormone

  6. Thyroid hormone transport into liver cells: its (patho)physiological significance

    NARCIS (Netherlands)

    M. de Jong (Marion)

    1993-01-01

    textabstractIn the experiments described in this thesis transmembrane transport of thyroid hormones into liver cells is investigated, in particular the regulatory role of this transport process in the bioavailability of thyroid hormones in (patho )fysiological conditions. This first chapter is an

  7. A multi-tiered, in vivo, quantitative assay suite for environmental disruptors of thyroid hormone signaling

    NARCIS (Netherlands)

    Mengeling, Brenda J.; Wei, Yuzhu; Dobrawa, Lucia N.; Streekstra, Mischa; Louisse, Jochem; Singh, Vikrant; Singh, Latika; Lein, Pamela J.; Wulff, Heike; Murk, Tinka; Furlow, J.D.

    2017-01-01

    The essential role of thyroid hormone (TH) signaling in mammalian development warrants the examination of man-made chemicals for its disruption. Among vertebrate species, the molecular components of TH signaling are highly conserved, including the thyroid hormone receptors (TRs), their heterodimer

  8. Reduced activation and increased inactivation of thyroid hormone in tissues of critically ill patients

    NARCIS (Netherlands)

    R.P. Peeters (Robin); P.J. Wouters (Pieter); E. Kaptein (Ellen); H. van Toor (Hans); T.J. Visser (Theo); G. van den Berghe (Greet)

    2003-01-01

    textabstractCritical illness is often associated with reduced TSH and thyroid hormone secretion as well as marked changes in peripheral thyroid hormone metabolism, resulting in low serum T(3) and high rT(3) levels. To study the mechanism(s) of the latter changes, we determined

  9. The involvement of thyroid hormones and cortisol in the osmotic acclimation of Solea senegalensis

    NARCIS (Netherlands)

    Arjona, F.J.; Vargas-Chacoff, L.; Rio, M.P. Martin Del; Flik, G.; Mancera, J.M.; Klaren, P.H.M.

    2007-01-01

    The peripheral conversion of the prohormone 3,5,3',5'-tetraiodothyronine (T4) to the biologically active 3,5,3'-triiodothyronine (T3), via enzymatic deiodination by deiodinases, is an important pathway in thyroid hormone metabolism. The aim of this study was to test if thyroid hormones and cortisol,

  10. Cell cycle control by the thyroid hormone in neuroblastoma cells

    International Nuclear Information System (INIS)

    Garcia-Silva, Susana; Perez-Juste, German; Aranda, Ana

    2002-01-01

    The thyroid hormone (T3) blocks proliferation and induces differentiation of neuroblastoma N2a-β cells that overexpress the β1 isoform of the T3 receptor. An element in the region responsible for premature termination of transcription mediates a rapid repression of c-myc gene expression by T3. The hormone also causes a decrease of cyclin D1 gene transcription, and is able to antagonize the activation of the cyclin D1 promoter by Ras. In addition, a strong and sustained increase of the levels of the cyclin kinase inhibitor (CKI) p27 Kip1 are found in T3-treated cells. The increased levels of p27 Kip1 lead to a marked inhibition of the kinase activity of the cyclin-CDK2 complexes. As a consequence of these changes, retinoblastoma proteins are hypophosphorylated in T3-treated N2a-β cells, and progression through the restriction point in the cell cycle is blocked

  11. Impact of monocarboxylate transporter-8 deficiency on the hypothalamus-pituitary-thyroid axis in mice

    NARCIS (Netherlands)

    M. Trajkovic-Arsic (Marija); J. Müller (Julia); V.M. Darras (Veerle); C. Groba (Claudia); S. Lee (Sooyeon); D. Weih (Debra); K. Bauer (Karl); T.J. Visser (Theo); H. Heuer (Heike)

    2010-01-01

    textabstractIn patients, inactivating mutations in the gene encoding the thyroid hormone-transporting monocarboxylate transporter 8 (Mct8) are associated with severe mental and neurological deficits and disturbed thyroid hormone levels. The latter phenotype characterized by high T3and low T4serum

  12. Skin morphological changes in growth hormone deficiency and acromegaly

    DEFF Research Database (Denmark)

    Lange, Merete Wolder; Thulesen, J; Feldt-Rasmussen, U

    2001-01-01

    To evaluate the histomorphology of skin and its appendages, especially eccrine sweat glands, in patients with GH disorders, because reduced sweating ability in patients with growth hormone deficiency (GHD) is associated with increased risk of hyperthermia under stressed conditions....

  13. Anxiety, memory impairment, and locomotor dysfunction caused by a mutant thyroid hormone receptor α1 can be ameliorated by T3 treatment

    Science.gov (United States)

    Venero, César; Guadaño-Ferraz, Ana; Herrero, Ana Isabel; Nordström, Kristina; Manzano, Jimena; de Escobar, Gabriella Moreale; Bernal, Juan; Vennström, Björn

    2005-01-01

    The transcriptional properties of unliganded thyroid hormone receptors are thought to cause the misdevelopment during hypothyroidism of several functions essential for adult life. To specifically determine the role of unliganded thyroid hormone receptor α1 (TRα1) in neuronal tissues, we introduced a mutation into the mouse TRα1 gene that lowers affinity to thyroid hormone (TH) 10-fold. The resulting heterozygous mice exhibit several distinct neurological abnormalities: extreme anxiety, reduced recognition memory, and locomotor dysfunction. The anxiety and memory deficiencies were relieved by treatment with high levels of TH in adulthood, an effect that correlated with a normalization of GABAergic inhibitory interneurons in the hippocampal CA1 region. In contrast, a post-natal TH treatment was necessary and sufficient for ameliorating the adult locomotor dysfunction. Here, the hormone treatment normalized the otherwise delayed cerebellar development. The data thus identify two novel and distinct functions of an unliganded TRα1 during development and adulthood, respectively. PMID:16131613

  14. Diagnostic significance of the serum thyroid hormone indicies in various thyroid diseases

    International Nuclear Information System (INIS)

    Han, B.H.; Ko, S.M.; Yoon, S.R.; Ro, H.K.

    1980-01-01

    In an attempt to evaluate the diagnostic significance of the serum thyroid hormones in various thyroid function states, the author measured serum T 3 uptake, serum T 3 , serum T 4 , serum free T 4 and free T 4 index in 27 cases of normal subjects, 11 cases of hypothyroidism, 152 cases of euthyroidism and 81 cases of hyperthyroidism by the radioimmunoassay method. The results were as follows: 1) The ranges of serum thyroid hormones in normal subjects were, serum T 3 uptake; 27.4-42.1%, serum T 3 ; 93-245 ng/dl, serum T 4 ; 4.08-12.9 ng/dl and serum free T 4 ; 0.57-1.53 ng/dl (M+-2 S.D.). 2) Free T 4 index and serum T 4 show relatively high diagnostic value in euthyroidism group, and serum T 3 and T 4 in hypothyroidism group, while serum T 3 , free T 4 and T 4 show relatively high diagnostic value in hyperthyroidism group. 3) There were significant correlation between free T 4 index and serum T 4 (r=0.68) and between free T 4 index and serum free T 4 (r=0.67) in hyperthyroidism group. (author)

  15. Skin morphological changes in growth hormone deficiency and acromegaly

    DEFF Research Database (Denmark)

    Lange, Merete Wolder; Thulesen, J; Feldt-Rasmussen, U

    2001-01-01

    To evaluate the histomorphology of skin and its appendages, especially eccrine sweat glands, in patients with GH disorders, because reduced sweating ability in patients with growth hormone deficiency (GHD) is associated with increased risk of hyperthermia under stressed conditions.......To evaluate the histomorphology of skin and its appendages, especially eccrine sweat glands, in patients with GH disorders, because reduced sweating ability in patients with growth hormone deficiency (GHD) is associated with increased risk of hyperthermia under stressed conditions....

  16. Thyroid hormones upregulate apolipoprotein E gene expression in astrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Roman, Corina; Fuior, Elena V.; Trusca, Violeta G. [Institute of Cellular Biology and Pathology “Nicolae Simionescu”, Bucharest (Romania); Kardassis, Dimitris [University of Crete Medical School and Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology of Hellas, Heraklion, Crete (Greece); Simionescu, Maya [Institute of Cellular Biology and Pathology “Nicolae Simionescu”, Bucharest (Romania); Gafencu, Anca V., E-mail: anca.gafencu@icbp.ro [Institute of Cellular Biology and Pathology “Nicolae Simionescu”, Bucharest (Romania)

    2015-12-04

    Apolipoprotein E (apoE), a protein mainly involved in lipid metabolism, is associated with several neurodegenerative disorders including Alzheimer's disease. Despite numerous attempts to elucidate apoE gene regulation in the brain, the exact mechanism is still uncovered. The mechanism of apoE gene regulation in the brain involves the proximal promoter and multienhancers ME.1 and ME.2, which evolved by gene duplication. Herein we questioned whether thyroid hormones and their nuclear receptors have a role in apoE gene regulation in astrocytes. Our data showed that thyroid hormones increase apoE gene expression in HTB14 astrocytes in a dose-dependent manner. This effect can be intermediated by the thyroid receptor β (TRβ) which is expressed in these cells. In the presence of triiodothyronine (T3) and 9-cis retinoic acid, in astrocytes transfected to overexpress TRβ and retinoid X receptor α (RXRα), apoE promoter was indirectly activated through the interaction with ME.2. To determine the location of TRβ/RXRα binding site on ME.2, we performed DNA pull down assays and found that TRβ/RXRα complex bound to the region 341–488 of ME.2. This result was confirmed by transient transfection experiments in which a series of 5′- and 3′-deletion mutants of ME.2 were used. These data support the existence of a biologically active TRβ binding site starting at 409 in ME.2. In conclusion, our data revealed that ligand-activated TRβ/RXRα heterodimers bind with high efficiency on tissue-specific distal regulatory element ME.2 and thus modulate apoE gene expression in the brain. - Highlights: • T3 induce a dose-dependent increase of apoE expression in astrocytes. • Thyroid hormones activate apoE promoter in a cell specific manner. • Ligand activated TRβ/RXRα bind on the distal regulatory element ME.2 to modulate apoE. • The binding site of TRβ/RXRα heterodimer is located at 409 bp on ME.2.

  17. Thyroid hormones upregulate apolipoprotein E gene expression in astrocytes

    International Nuclear Information System (INIS)

    Roman, Corina; Fuior, Elena V.; Trusca, Violeta G.; Kardassis, Dimitris; Simionescu, Maya; Gafencu, Anca V.

    2015-01-01

    Apolipoprotein E (apoE), a protein mainly involved in lipid metabolism, is associated with several neurodegenerative disorders including Alzheimer's disease. Despite numerous attempts to elucidate apoE gene regulation in the brain, the exact mechanism is still uncovered. The mechanism of apoE gene regulation in the brain involves the proximal promoter and multienhancers ME.1 and ME.2, which evolved by gene duplication. Herein we questioned whether thyroid hormones and their nuclear receptors have a role in apoE gene regulation in astrocytes. Our data showed that thyroid hormones increase apoE gene expression in HTB14 astrocytes in a dose-dependent manner. This effect can be intermediated by the thyroid receptor β (TRβ) which is expressed in these cells. In the presence of triiodothyronine (T3) and 9-cis retinoic acid, in astrocytes transfected to overexpress TRβ and retinoid X receptor α (RXRα), apoE promoter was indirectly activated through the interaction with ME.2. To determine the location of TRβ/RXRα binding site on ME.2, we performed DNA pull down assays and found that TRβ/RXRα complex bound to the region 341–488 of ME.2. This result was confirmed by transient transfection experiments in which a series of 5′- and 3′-deletion mutants of ME.2 were used. These data support the existence of a biologically active TRβ binding site starting at 409 in ME.2. In conclusion, our data revealed that ligand-activated TRβ/RXRα heterodimers bind with high efficiency on tissue-specific distal regulatory element ME.2 and thus modulate apoE gene expression in the brain. - Highlights: • T3 induce a dose-dependent increase of apoE expression in astrocytes. • Thyroid hormones activate apoE promoter in a cell specific manner. • Ligand activated TRβ/RXRα bind on the distal regulatory element ME.2 to modulate apoE. • The binding site of TRβ/RXRα heterodimer is located at 409 bp on ME.2.

  18. Pleiotropic Effects of Thyroid Hormones: Learning from Hypothyroidism

    Directory of Open Access Journals (Sweden)

    Martha Franco

    2011-01-01

    Full Text Available Hypothyroidism induces several metabolic changes that allow understanding some physiopathological mechanisms. Under experimental hypothyroid conditions in rats, heart and kidney are protected against oxidative damage induced by ischemia reperfusion. An increased resistance to opening of the permeability transition pore seems to be at the basis of such protection. Moreover, glomerular filtration rate of hypothyroid kidney is low as a result of adenosine receptors-induced renal vasoconstriction. The vascular tone of aorta is also regulated by adenosine in hypothyroid conditions. In other context, thyroid hormones regulate lipoprotein metabolism. High plasma level of LDL cholesterol is a common feature in hypothyroidism, due to a low expression of the hepatic LDL receptor. In contrast, HDL-cholesterol plasma levels are variable in hypothyroidism; several proteins involved in HDL metabolism and structure are expressed at lower levels in experimental hypothyroidism. Based on the positive influence of thyroid hormones on lipoprotein metabolism, thyromimetic drugs are promising for the treatment of dyslipidemias. In summary, hypothyroid status has been useful to understand molecular mechanisms involved in ischemia reperfusion, regulation of vascular function and intravascular metabolism of lipoproteins.

  19. Transcriptional regulation by nonclassical action of thyroid hormone

    Directory of Open Access Journals (Sweden)

    Moeller Lars C

    2011-08-01

    Full Text Available Abstract Thyroid hormone (TH is essential for normal development, growth and metabolism. Its effects were thought to be principally mediated through triiodothyronine (T3, acting as a ligand for the nuclear TH receptors (TRs α and β residing on thyroid hormone response elements (TREs in the promoter of TH target genes. In this classical model of TH action, T3 binding to TRs leads to recruitment of basal transcription factors and increased transcription of TH responsive genes. Recently, the concept of TH action on gene expression has become more diverse and now includes nonclassical actions of T3 and T4: T3 has been shown to activate PI3K via the TRs, which ultimately increases transcription of certain genes, e.g. HIF-1α. Additionally, both T3 and thyroxine (T4 can bind to a membrane integrin, αvβ3, which leads to activation of the PI3K and MAPK signal transduction pathways and finally also increases gene transcription, e.g. of the FGF2 gene. Therefore, these initially nongenomic, nonclassical actions seem to serve as additional interfaces for transcriptional regulation by TH. Aim of this perspective is to summarize the genes that are currently known to be induced by nonclassical TH action and the mechanisms involved.

  20. Metastatic Follicular Thyroid Carcinoma Secreting Thyroid Hormone and Radioiodine Avid without Stimulation: A Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Syed A. Abid

    2014-01-01

    Full Text Available Introduction. This is an extremely rare case of a patient with metastatic follicular thyroid cancer who continued to produce thyroid hormone and was iodine scan positive without stimulation after thyroidectomy and radioiodine (I-131 therapy. Patient Findings. A 76-year-old Caucasian male was diagnosed with metastatic follicular thyroid carcinoma on lung nodule biopsy. Total thyroidectomy was performed and he was ablated with 160 mCi of I-131 after recombinant human thyrotropin (rhTSH stimulation. Whole body scan (WBS after treatment showed uptake in bilateral lungs, right sacrum, and pelvis. The thyroglobulin decreased from 2,063 to 965 four months after treatment but rapidly increased to 2,506 eleven months after I-131. Thyroid stimulating hormone (TSH remained suppressed and free T4 remained elevated after I-131 therapy without thyroid hormone supplementation. He was treated with an additional 209 mCi with WBS findings positive in lung and pelvis. Despite I-131, new metastatic lesions were noted in the left thyroid bed and large destructive lesion to the first cervical vertebrae four months after the second I-131 dose. Conclusions. This case is exceptional because of its rarity and also due to the dissociation between tumor differentiation and aggressiveness. The metastatic lesions continued to secrete thyroid hormone and remained radioiodine avid with rapid progression after I-131 therapy.

  1. Growth hormone deficiency in a Nigerian child with Turner's syndrome

    African Journals Online (AJOL)

    IRORO YARHERE

    Growth hormone deficiency in a Nigerian child with Turner's syndrome: a case report and review of growth assessment in .... when the sex hormonal influence is absent. The good thing about our ... was due to lack of oestradiol influence in amplifying the neuroendocrine regulation of pulsatile GH release, but our patient's ...

  2. Histological and ultrastructural alterations of rat thyroid gland after short-term treatment with high doses of thyroid hormones.

    Science.gov (United States)

    Ali Rajab, Njia M; Ukropina, Mirela; Cakic-Milosevic, Maja

    2017-09-01

    The aim of the present study was to investigate histological alterations of rat thyroid gland after short-term treatment with supraphysiological doses of thyroid hormones. Rats from experimental groups were treated with triiodothyronine (T3) or thyroxine (T4) during five days. In both treated groups, thyrocyte height was reduced and follicular lumens were distended. Progressive involutive changes of the thyroid parenchyma were apparent, including follicular remodeling (fusion) and death of thyrocytes. Morphological changes confirmed by quantitative analysis were more pronounced in the T4-treated group. Our results demonstrate that thyrotoxicosis, whether induced by T3 or T4, leads to different grades of thyroid tissue injury, including some irreversible damages. These changes might be explained at least in part by lack of trophic and cytoprotective effects of the thyroid stimulating hormone. Since the period required for morphophysiological recovery may be unpredictable, findings presented here should be taken into consideration in cases where the thyroid hormones are used as a treatment for thyroid and non-thyroid related conditions.

  3. Effects of thyroid hormone withdrawal on natriuretic peptides during radioactive iodine therapy in female patients with differentiated thyroid cancer.

    Science.gov (United States)

    Stanciu, Adina Elena; Hurduc, Anca Elena; Stanciu, Marcel Marian

    2016-12-01

    We aimed to investigate the effects of thyroid hormone withdrawal on N-terminal prohormone forms of atrial natriuretic peptide (NT-proANP) and brain natriuretic peptide (NT-proBNP) during radioiodine therapy in female patients with differentiated thyroid cancer (DTC). Serum concentrations of thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), NT-proANP and NT-proBNP were measured in 51 female patients with DTC (48.7 ± 4.2 years) at three time-points: day of radioiodine therapy (t1 - under acute hypothyroidism), 5 days after radioiodine (t2 - under acute hypothyroidism) and 3 months after radioiodine (t3 - under TSH suppression). Thirty healthy euthyroid women served as controls (42.8 ± 5.6 years). At t1/t2/t3, median NT-proANP was 5.2/1.7/487 pmol/L vs. 297.7 pmol/L in control group (p thyroid hormone effects than NT-proBNP. Thyroid hormone-dependent hemodynamic effects seem to be overlapped on the direct stimulatory effect of thyroid hormones on NT-proANP secretion by cardiac myocytes.

  4. Association of vitamin D insufficiency/deficiency with thyroid artery Doppler ultrasonography in patients with Hashimoto thyroiditis.

    Science.gov (United States)

    Nalbant, Ahmet; Aydin, Ayhan; Karacan, Alper; Onmez, Attila; Tamer, Ali; Cinemre, Hakan

    2017-01-01

    During the course of the autoimmune thyroid diseases, ultrasonography change parallel to histopathology. Vitamin D is associated with autoimmune diseases and thus can affect thyroid blood flow. Our aim was to investigate the relationship between vitamin D insufficiency/deficiency and thyroid hemodynamic indices in patients with Hashimoto thyroiditis. A total of 93 patients who presented to Sakarya University Endocrinology outpatient clinic from April to September 2016 and diagnosed with Hashimoto thyroiditis were included in this study. Clinical and serologic data, thyroid antibodies and 25(OH)D3 were evaluated. Mean peak systolic velocity(mPSV), mean end-diastolic velocity (EDV), mean resistive index (RI) flows of superior and inferior thyroid arteries were measured with B-mode Doppler ultrasonography. Vitamin D insufficiency/deficiency was detected in 59 (63.4%). TPO Ab and TgAb levels were found higher in patients with vitamin D insufficiency/deficiency. In the normal vitamin D group, superior thyroid artery mPSV (32.21±6.73cm/s) and EDV(13.27±2.80 cm/s) were higher than in the low vitamin D group [mPSV (28.32±8.99cm/s) and EDV(10.67±3.68 cm/s)] (P=0.034, P=0.001, respectively). Inferior thyroid artery EDV value was higher in the normal compared to the low vitamin D group (0.032). RI measured in all arteries were higher in the vitamin D insufficient/deficient group compared to the Vitamin D normal group (p=0.001). Vitamin-D insufficiency/deficiency has led to reduced parenchymal blood supply and increased micro-vascular resistance in Hashimoto thyroiditis patients.

  5. Molecules important for thyroid hormone synthesis and action - known facts and future perspectives

    Directory of Open Access Journals (Sweden)

    Brix Klaudia

    2011-08-01

    Full Text Available Abstract Thyroid hormones are of crucial importance for the functioning of nearly every organ. Remarkably, disturbances of thyroid hormone synthesis and function are among the most common endocrine disorders affecting approximately one third of the working German population. Over the last ten years our understanding of biosynthesis and functioning of these hormones has increased tremendously. This includes the identification of proteins involved in thyroid hormone biosynthesis like Thox2 and Dehal where mutations in these genes are responsible for certain degrees of hypothyroidism. One of the most important findings was the identification of a specific transporter for triiodothyronine (T3, the monocarboxylate transporter 8 (MCT8 responsible for directed transport of T3 into target cells and for export of thyroid hormones out of thyroid epithelial cells. Genetic disturbances of MCT8 in patients result in a biochemical constellation of high T3 levels in combination with low or normal TSH and thyroxine levels leading to a new syndrome of severe X-linked mental retardation. Importantly mice lacking MCT8 presented only with a mild phenotype, indicating that compensatory mechanisms exist in mice. Moreover, it has become clear that not only genomic actions of T3 exist. T3 is also capable to activate adhesion receptors and it signals via activation of PI3K and MAPK pathways. Most recently, thyroid hormone derivatives were identified, the thyronamines which are decarboxylated thyroid hormones initiating physiological actions like lowering body temperature and heart rate, thereby acting in opposite direction to the classical thyroid hormones. So far it is believed that thyronamines function via the activation of a G-protein coupled receptor, TAAR1. The objective of this review is to summarise the recent findings in thyroid hormone synthesis and action and to discuss their implications for diagnosis of thyroid disease and for treatment of patients.

  6. Thyroid Hormone and P-Glycoprotein in Tumor Cells

    Directory of Open Access Journals (Sweden)

    Paul J. Davis

    2015-01-01

    Full Text Available P-glycoprotein (P-gp; multidrug resistance pump 1, MDR1; ABCB1 is a plasma membrane efflux pump that when activated in cancer cells exports chemotherapeutic agents. Transcription of the P-gp gene (MDR1 and activity of the P-gp protein are known to be affected by thyroid hormone. A cell surface receptor for thyroid hormone on integrin αvβ3 also binds tetraiodothyroacetic acid (tetrac, a derivative of L-thyroxine (T4 that blocks nongenomic actions of T4 and of 3,5,3′-triiodo-L-thyronine (T3 at αvβ3. Covalently bound to a nanoparticle, tetrac as nanotetrac acts at the integrin to increase intracellular residence time of chemotherapeutic agents such as doxorubicin and etoposide that are substrates of P-gp. This action chemosensitizes cancer cells. In this review, we examine possible molecular mechanisms for the inhibitory effect of nanotetrac on P-gp activity. Mechanisms for consideration include cancer cell acidification via action of tetrac/nanotetrac on the Na+/H+ exchanger (NHE1 and hormone analogue effects on calmodulin-dependent processes and on interactions of P-gp with epidermal growth factor (EGF and osteopontin (OPN, apparently via αvβ3. Intracellular acidification and decreased H+ efflux induced by tetrac/nanotetrac via NHE1 is the most attractive explanation for the actions on P-gp and consequent increase in cancer cell retention of chemotherapeutic agent-ligands of MDR1 protein.

  7. Identification and consequences of polymorphisms in the thyroid hormone receptor alpha and beta genes

    DEFF Research Database (Denmark)

    Sørensen, Helena Gásdal; van der Deure, Wendy M; Hansen, Pia Skov

    2008-01-01

    OBJECTIVE: Genetic factors exert considerable influence on thyroid function variables. Single nucleotide polymorphisms (SNPs) in thyroid hormone pathway genes have been associated with serum thyroid parameters implying small alterations in the hypothalamus-pituitary-thyroid axis. However, little...... SNPs in the 3' untranslated region of THRA were genotyped: a novel SNP (2390A/G) and 1895C/A (rs12939700). In THRB, a synonymous (735C/T; rs3752874) and an intronic SNP (in9-G/A; rs13063628) were genotyped. No associations between SNPs and thyroid hormone levels (total and free 3,3',5-triiodo......-L-thyronine [T3] and thyroxine, reverse T3) were found. THRB-in9-G/A was significantly associated with higher serum thyroid stimulating hormone (TSH) (p(lnTSH) = 0.01) in the Danish twins, but not in subjects of the Rotterdam Scan Study, although it showed a similar trend. CONCLUSIONS: Analysis of the T3...

  8. Implications of the thyroid hormone on neuronal development with special emphasis on the calmodulin-kinase IV pathway.

    Science.gov (United States)

    Krebs, Joachim

    2017-06-01

    Thyroid hormones influence brain development through regulation of gene expression. This is especially true for Ca 2+ -dependent regulation since a major pathway is controlled by the Ca 2+ /calmodulin-dependent protein kinase IV (CaMKIV) which in turn is induced by the thyroid hormone T 3 . In addition, CaMKIV is involved in regulation of alternative splicing of a number of protein isoforms, among them PMCA1a, the neuronal specific isoform of the plasma membrane calcium pump. On the other hand, hypothyroidism or CaMKIV deficiency can have a severe influence on brain development. This article is part of a Special Issue entitled: ECS Meeting edited by Claus Heizmann, Joachim Krebs and Jacques Haiech. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Identification of Thyroid Hormones and Functional Characterization of Thyroid Hormone Receptor in the Pacific Oyster Crassostrea gigas Provide Insight into Evolution of the Thyroid Hormone System.

    Science.gov (United States)

    Huang, Wen; Xu, Fei; Qu, Tao; Zhang, Rui; Li, Li; Que, Huayong; Zhang, Guofan

    2015-01-01

    Thyroid hormones (THs) play important roles in development, metamorphosis, and metabolism in vertebrates. During the past century, TH functions were regarded as a synapomorphy of vertebrates. More recently, accumulating evidence has gradually convinced us that TH functions also occur in invertebrate chordates. To date, however, TH-related studies in non-chordate invertebrates have been limited. In this study, THs were qualitatively detected by two reliable methods (HPLC and LC/MS) in a well-studied molluscan species, the Pacific oyster Crassostrea gigas. Quantitative measurement of THs during the development of C. gigas showed high TH contents during embryogenesis and that oyster embryos may synthesize THs endogenously. As a first step in elucidating the TH signaling cascade, an ortholog of vertebrate TH receptor (TR), the most critical gene mediating TH effects, was cloned in C. gigas. The sequence of CgTR has conserved DNA-binding and ligand-binding domains that normally characterize these receptors. Experimental results demonstrated that CgTR can repress gene expression through binding to promoters of target genes and can interact with oyster retinoid X receptor. Moreover, CgTR mRNA expression was activated by T4 and the transcriptional activity of CgTR promoter was repressed by unliganded CgTR protein. An atypical thyroid hormone response element (CgDR5) was found in the promoter of CgTR, which was verified by electrophoretic mobility shift assay (EMSA). These results indicated that some of the CgTR function is conserved. However, the EMSA assay showed that DNA binding specificity of CgTR was different from that of the vertebrate TR and experiments with two dual-luciferase reporter systems indicated that l-thyroxine, 3,3',5-triiodothyronine, and triiodothyroacetic acid failed to activate the transcriptional activity of CgTR. This is the first study to functionally characterize TR in mollusks. The presence of THs and the functions of CgTR in mollusks contribute

  10. Epidermal growth factor (EGF) inhibits stimulated thyroid hormone secretion in the mouse

    International Nuclear Information System (INIS)

    Ahren, B.

    1987-01-01

    It is known that epidermal growth factor (EGF) inhibits iodide uptake in the thyroid follicular cells and lowers plasma levels of thyroid hormones upon infusion into sheep and ewes. In this study, the effects of EGF on basal and stimulated thyroid hormone secretion were investigated in the mouse. Mice were pretreated with 125 I and thyroxine; the subsequent release of 125 I is an estimation of thyroid hormone secretion. It was found that basal radioiodine secretion was not altered by intravenous injection of EGF (5 micrograms/animal). However, the radioiodine secretion stimulated by both TSH (120 microU/animal) and vasoactive intestinal peptide (VIP; 5 micrograms/animal) were inhibited by EGF (5 micrograms/animal). At a lower dose level (0.5 microgram/animal), EGF had no influence on stimulated radioiodine secretion. In conclusion, EGF inhibits stimulated thyroid hormone secretion in the mouse

  11. Inhibition of the thyroid hormone pathway in Xenopus laevis by 2-mercaptobenzothiazole

    Energy Technology Data Exchange (ETDEWEB)

    Tietge, Joseph E., E-mail: tietge.joe@epa.gov [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd, Duluth, MN 55804 (United States); Degitz, Sigmund J., E-mail: degitz.sigmund@epa.gov [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd, Duluth, MN 55804 (United States); Haselman, Jonathan T., E-mail: haselman.jon@epa.gov [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd, Duluth, MN 55804 (United States); Butterworth, Brian C., E-mail: butterworth.brian@epa.gov [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd, Duluth, MN 55804 (United States); Korte, Joseph J., E-mail: korte.joe@epa.gov [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd, Duluth, MN 55804 (United States); Kosian, Patricia A., E-mail: kosian.pat@epa.gov [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd, Duluth, MN 55804 (United States); Lindberg-Livingston, Annelie J., E-mail: lind1020@d.umn.edu [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd, Duluth, MN 55804 (United States); and others

    2013-01-15

    Determining the effects of chemicals on the thyroid system is an important aspect of evaluating chemical safety from an endocrine disrupter perspective. Since there are numerous chemicals to test and limited resources, prioritizing chemicals for subsequent in vivo testing is critical. 2-Mercaptobenzothiazole (MBT), a high production volume chemical, was tested and shown to inhibit thyroid peroxidase (TPO) enzyme activity in vitro, a key enzyme necessary for the synthesis of thyroid hormone. To determine the thyroid disrupting activity of MBT in vivo, Xenopus laevis larvae were exposed using 7- and 21-day protocols. The 7-day protocol used 18-357 {mu}g/L MBT concentrations and evaluated: metamorphic development, thyroid histology, circulating T4, circulating thyroid stimulating hormone, thyroidal sodium-iodide symporter gene expression, and thyroidal T4, T3, and related iodo-amino acids. The 21-day protocol used 23-435 {mu}g/L MBT concentrations and evaluated metamorphic development and thyroid histology. Both protocols demonstrated that MBT is a thyroid disrupting chemical at the lowest concentrations tested. These studies complement the in vitro study used to identify MBT as a high priority for in vivo testing, supporting the utility/predictive potential of a tiered approach to testing chemicals for TPO activity inhibition. The 7-day study, with more comprehensive, sensitive, and diagnostic endpoints, provides information at intermediate biological levels that enables linking various endpoints in a robust and integrated pathway for thyroid hormone disruption associated with TPO inhibition.

  12. Etiology of growth hormone deficiency in children and adolescents

    Directory of Open Access Journals (Sweden)

    Mitrović Katarina

    2013-01-01

    Full Text Available Introduction. Growth hormone deficiency (GHD can be isolated or associated with deficiency of other pituitary gland hormones. According to age at diagnosis, causes of GHD are divided into congenital or acquired, and according to etiology into recognized and unknown. Objective. We analyzed etiology and prevalence of GHD, demographic data at birth, age, body height (BH and bone age at diagnosis as well as the frequency of other pituitary hormone deficiencies. Methods. The study involved 164 patients (109 male. The main criterion for the diagnosis of GHD was inadequate response of GH after two stimulation tests. The patients were classified into three groups: idiopathic, congenital and acquired GHD. Results. Idiopathic GHD was confirmed in 57.9% of patients, congenital in 11.6% and acquired in 30.5%. The mean age at diagnosis of GHD was 10.1±4.5 years. The patients with congenital GHD had most severe growth retardation (-3.4±1.4 SDS, while the patients with idiopathic GHD showed most prominent bone delay (-3.6±2.3 SDS. The prevalence of multiple pituitary hormone deficiency was 56.1%, in the group with congenital GHD 73.7%, acquired GHD 54.0% and idiopathic GHD 53.7%. The frequency of thyrotropin deficiency ranged from 88.2-100%, of adrenocorticotrophin 57.1-68.8% and of gonadotrophins deficiency 57.1- 63.0%, while deficiency of antidiuretic hormone was 2.0-25.0%. Conclusion. Although regular BH measurements enable early recognition of growth retardation, patients’ mean age and degree of growth retardation indicate that GHD is still diagnosed relatively late. A high incidence of other pituitary hormone deficiencies requires a detailed investigation of the etiology of disorders and evaluation of all pituitary functions in each child with confirmed GHD.

  13. Growth hormone deficiency and hyperthermia during exercise

    DEFF Research Database (Denmark)

    Juul, A; Hjortskov, N; Jepsen, Leif

    1995-01-01

    levels [11 with multiple pituitary deficiency (MPD) and 5 with isolated GH deficiency] and in 10 healthy subjects as controls (CTs). Each subject exercised on a bicycle ergometer for 60 min at a workload corresponding to 45% of their individual maximal oxygen consumption (VO2max), in a room maintained...

  14. Differentiated thyroid cancer in patients with resistance to thyroid hormone syndrome. A novel case and a review of the literature.

    Science.gov (United States)

    Vinagre, João; Borges, Fátima; Costa, António; Alvelos, Maria Inês; Mazeto, Glaúcia; Sobrinho-Simões, Manuel; Soares, Paula

    2014-01-01

    Resistance to thyroid hormone (RTH) represents a syndrome in which patients present elevated circulating thyroid hormones in the presence of non-suppressed TSH. We report a novel case where a patient with RTH presented a differentiated thyroid cancer. A19 year-old female had been referred due to thyroid disease that disclosed features characteristic of a RTH. During the follow up it was detected a follicular tumor that led to the recommendation for thyroid surgical ablation, where an incidental papillary thyroid microcarcinoma (mPTC) was found. The increase of thyroglobulin (TG) levels following thyroid removal referred the patient for radioiodine treatment. Post-treatment, it was detected jugular adenopathies and the patient was subjected to cervical lymph node drainage where metastases of the mPTC were found. RTH syndrome was confirmed by the detection of a THRB germline mutation. A BRAF mutation was also found in the mPTC but not detected in the follicular adenoma or normal adjacent tissue. The young age of the patient, the rarity of BRAF mutations in childhood and the high dissemination of the malignancy, lead us to the speculation that increased TSH stimulation in a RTH background and oncogenic activation of BRAF could have served as (co) drivers and might have triggered an advanced stage of the neoplastic disease. These findings together with a review of published cases add novel information to the management of RTH patients with differentiated thyroid cancer.

  15. Effects of Growth Hormone Replacement Therapy on Bone Mineral Density in Growth Hormone Deficient Adults: A Meta-Analysis

    OpenAIRE

    Xue, Peng; Wang, Yan; Yang, Jie; Li, Yukun

    2013-01-01

    Objectives. Growth hormone deficiency patients exhibited reduced bone mineral density compared with healthy controls, but previous researches demonstrated uncertainty about the effect of growth hormone replacement therapy on bone in growth hormone deficient adults. The aim of this study was to determine whether the growth hormone replacement therapy could elevate bone mineral density in growth hormone deficient adults. Methods. In this meta-analysis, searches of Medline, Embase, and The Cochr...

  16. The Influence of Antiepileptic Drugs on Thyroid Hormon Levels

    Directory of Open Access Journals (Sweden)

    İsmail Apak

    2006-01-01

    Full Text Available Fourty epileptic patients who were followed at Neurology Department of Diyarbakır Dicle University Medical School and taking antiepileptic drugs for at least a year, were included in the study. Twenty of patients (50% were male and 20 (50% were female. Patients were divided into 3 groups according to drugs they were treated with. The age range of 14 patients using valproate were between 15 and 44 years (mean 27.7 and they were taking the medication for 1 to 4 years (mean 2.67 years. Ages of 11 patients taking phenytoin were between 18 and 41 years (mean 28.7. Fifteen patients taking carbamazepine were between 16 and 43 years of age (mean 28.5 and duration of their therapy were 1 to 3 years (mean 2.6. The aim of this study was to search the effects of antiepileptic drugs on thyroid hormone levels in epileptic patients. Levels of T4, FT4, T3, FT3 and TSH were analyzed and following results were obtained. In group of patients receiving valproate, T4 levels decreased significantly. No change has been detected at FT4, T3.FT3 and TSH levels. T4 and FT4 levels decreased significantly at the patients using phenytoin. No change has been observed at T3, FT3 and TSH levels. There were no significant changes at T3, FT3 and TSH levels in the group of patients taking carbamazepine, however T4 and FT4 levels decreased significantly. The decrease at T4 levels were greater at carbamazepine, valproat and phenytoin, respectively. The most prominent decrease of FT4 levels were at the group taking phenytoin while the group treated with valproate were effected the least. The results of this study has shown that antiepileptic drugs affect thyroid functions, and patients using these drugs should be regularly followed up for any possible thyroid dysfunction.

  17. Growth hormone deficiency in cleft lip and palate patients

    Directory of Open Access Journals (Sweden)

    Shahin AbdollahiFakhim

    2015-11-01

    Full Text Available Introduction: Failure to thrive (FTT is relatively common among cleft patients, most commonly attributed to feeding problems during the first months of life. Close association between midline clefts and pituitary gland abnormalities prompted us to determine the frequency of growth hormone deficiency in cleft patients, which is easily treated. Methods: Any cleft patient with FTT was studied and when the patient’s height was under the 3rd percentile of normal, growth hormone was checked after clonidine administration. Growth hormone was checked before and 30, 60 and 90 minutes after clonidine use. Results: Of 670 patients with cleft lip or palate, 31 patients (4% had some kind of growth retardation according to weight, height or head circumstance. Eighteen patients were under the 3rd percentile of normal height. Growth hormone deficiency was detected in 8 patients out of 18 patients and overall frequency of growth hormone deficiency among cleft patients with growth retardation was 25.8% (8 out of 31. Seven patients of 8 were male whereas one was female and half of the patients were syndromic. Conclusion: Cleft patients have many problems with normal feeding and all kind of support should be provided to achieve near-normal feeding and they should be monitored for normal growth. Any patient with growth retardation, especially height decrease, should be assessed for growth hormone deficiency.

  18. The c-erb-A protein is a high-affinity receptor for thyroid hormone

    DEFF Research Database (Denmark)

    Sap, J; Muñoz, A; Damm, K

    1987-01-01

    Hormone binding and localization of the c-erb-A protein suggest that it is a receptor for thyroid hormone, a nuclear protein that binds to DNA and activates transcription. In contrast, the product of the viral oncogene v-erb-A is defective in binding the hormone but is still located in the nucleus....

  19. Vulnerability of the developing brain to thyroid abnormalities: environmental insults to the thyroid system.

    OpenAIRE

    Porterfield, S P

    1994-01-01

    Neurologic development follows orderly patterns that can be severely disturbed when thyroid hormones are deficient or excessive. Should this occur at appropriate development periods, irreversible neurologic damage can result. The nature of the deficits depends upon the specific development period and the severity of the thyroid disturbance. PCBs and dioxins are structurally similar to the thyroid hormones. Their binding characteristics are similar to those of thyroid hormones and all three gr...

  20. Thyroid Hormone Availability and Action during Brain Development in Rodents

    Directory of Open Access Journals (Sweden)

    Soledad Bárez-López

    2017-08-01

    Full Text Available Thyroid hormones (THs play an essential role in the development of all vertebrates; in particular adequate TH content is crucial for proper neurodevelopment. TH availability and action in the brain are precisely regulated by several mechanisms, including the secretion of THs by the thyroid gland, the transport of THs to the brain and neural cells, THs activation and inactivation by the metabolic enzymes deiodinases and, in the fetus, transplacental passage of maternal THs. Although these mechanisms have been extensively studied in rats, in the last decade, models of genetically modified mice have been more frequently used to understand the role of the main proteins involved in TH signaling in health and disease. Despite this, there is little knowledge about the mechanisms underlying THs availability in the mouse brain. This mini-review article gathers information from findings in rats, and the latest findings in mice regarding the ontogeny of TH action and the sources of THs to the brain, with special focus on neurodevelopmental stages. Unraveling TH economy and action in the mouse brain may help to better understand the physiology and pathophysiology of TH signaling in brain and may contribute to addressing the neurological alterations due to hypo and hyperthyroidism and TH resistance syndromes.

  1. Impact of Endocrine Disruptors on the Thyroid Hormone System.

    Science.gov (United States)

    Gutleb, Arno C; Cambier, Sébastien; Serchi, Tommaso

    2016-01-01

    The thyroid hormone (TH) system plays a central role in central physiological processes of many species, including mammals and humans, ranging from growth and cell differentiation, energy metabolism, thermoregulation and phasing of hibernation or annual movements of migratory species, metamorphosis from larvae to adult forms, brain development, reproduction, or the cardiovascular system. Several chemicals are known to be TH-disrupting compounds (THDCs) and have been shown to interact with virtually all elements of TH homeostasis such as feedback mechanisms with the hypothalamus-pituitary axis, TH synthesis, TH storage and release from the thyroid gland, transport protein binding and TH distribution in tissues and organs, cellular TH uptake, intracellular TH metabolism, and TH receptor binding. Therefore, chemicals interfering with the TH homeostasis have the potential to interact with many of these important processes, and especially early-life stage exposure results in permanent alterations of tissue organization and homeostatic regulation of adaptive processes. This is not only of theoretical importance as the reported plasma concentrations of THDCs in human plasma fall well within the range of reported in vitro effect concentrations, and this is of even higher importance as the developing fetus and young children are in a sensitive developmental stage. © 2016 S. Karger AG, Basel.

  2. Thyroid hormones regulate selenoprotein expression and selenium status in mice.

    Directory of Open Access Journals (Sweden)

    Jens Mittag

    Full Text Available Impaired expression of selenium-containing proteins leads to perturbed thyroid hormone (TH levels, indicating the central importance of selenium for TH homeostasis. Moreover, critically ill patients with declining serum selenium develop a syndrome of low circulating TH and a central downregulation of the hypothalamus-pituitary-thyroid axis. This prompted us to test the reciprocal effect, i.e., if TH status would also regulate selenoprotein expression and selenium levels. To investigate the TH dependency of selenium metabolism, we analyzed mice expressing a mutant TH receptor α1 (TRα1+m that confers a receptor-mediated hypothyroidism. Serum selenium was reduced in these animals, which was a direct consequence of the mutant TRα1 and not related to their metabolic alterations. Accordingly, hyperthyroidism, genetically caused by the inactivation of TRβ or by oral TH treatment of adult mice, increased serum selenium levels in TRα1+m and controls, thus demonstrating a novel and specific role for TRα1 in selenium metabolism. Furthermore, TH affected the mRNA levels for several enzymes involved in selenoprotein biosynthesis as well as serum selenoprotein P concentrations and the expression of other antioxidative selenoproteins. Taken together, our results show that TH positively affects the serum selenium status and regulates the expression of several selenoproteins. This demonstrates that selenium and TH metabolism are interconnected through a feed-forward regulation, which can in part explain the rapid parallel downregulation of both systems in critical illness.

  3. Reference intervals of thyroid hormones during pregnancy in Korea, an iodine-replete area.

    Science.gov (United States)

    Kim, Hye Jeong; Cho, Yoon Young; Kim, Sun Wook; Kim, Tae Hyuk; Jang, Hye Won; Lee, Soo-Youn; Choi, Suk-Joo; Roh, Cheong-Rae; Kim, Jong-Hwa; Chung, Jae Hoon; Oh, Soo-Young

    2017-02-08

    Maternal thyroid dysfunction has been associated with adverse pregnancy outcomes. The purpose of our study was to establish trimester-specific reference intervals for thyroid hormones in pregnant women in Korea, where iodine intake is more than adequate and to examine pregnancy and perinatal outcomes in their offspring. Among 459 healthy pregnant women who were screened, we enrolled 417 subjects who had negative results for thyroid autoantibodies. Serum thyroid stimulating hormone (TSH) and free thyroxine were measured using an immunoradiometric assay. Urine iodine concentration was measured using inductively coupled plasma-mass spectrometry in 275 women. Reference ranges of thyroid hormones were determined according to the guidelines of the National Academy of Clinical Biochemistry. Pregnancy and perinatal outcomes were compared according to maternal thyroid function. The reference ranges of serum TSH were 0.03 to 4.24 mIU/L in the first trimester, 0.13 to 4.84 mIU/L in the second trimester, and 0.30 to 5.57 mIU/L in the third trimester. Pregnancy and perinatal outcomes did not vary in mothers with subtle changes in thyroid function. Trimester-specific thyroid hormone reference intervals in Korean pregnant women differ from those of other countries with different iodine nutrition status and ethnicity. The establishment of population-based, reliable trimester-specific reference intervals is critical for the interpretation of thyroid function in pregnant women to avoid unnecessary tests and treatments.

  4. Growth hormone deficiency and hyperthermia during exercise

    DEFF Research Database (Denmark)

    Juul, A; Hjortskov, N; Jepsen, Leif

    1995-01-01

    Sweat secretion is often disturbed in patients with GH secretory disorders. Hyperhidrosis is a classic feature of acromegaly, and it has recently been shown that GH-deficient patients exhibit decreased sweating capacity after pilocarpine stimulation of the skin. Thus, patients with GH-deficiency ......Sweat secretion is often disturbed in patients with GH secretory disorders. Hyperhidrosis is a classic feature of acromegaly, and it has recently been shown that GH-deficient patients exhibit decreased sweating capacity after pilocarpine stimulation of the skin. Thus, patients with GH...

  5. Growth hormone deficiency and hyperthermia during exercise

    DEFF Research Database (Denmark)

    Juul, A; Hjortskov, N; Jepsen, Leif

    1995-01-01

    levels [11 with multiple pituitary deficiency (MPD) and 5 with isolated GH deficiency] and in 10 healthy subjects as controls (CTs). Each subject exercised on a bicycle ergometer for 60 min at a workload corresponding to 45% of their individual maximal oxygen consumption (VO2max), in a room maintained......-deficiency may be at risk for developing hyperthermia. To pursue this, we performed a controlled study on sweating and body temperature regulation during exercise in the heat in 16 GH-treated GH-deficient patients with normalized insulin-like growth factor-I and insulin-like growth factor/binding protein-3 serum...... at 35 C. GH serum concentrations increased significantly after approximately 10 min of exercise in the CTs (P

  6. Screening the Tox21 10K library for thyroid stimulating hormone receptor agonist and antagonist activity (SOT annual meeting)

    Science.gov (United States)

    Thyroid-stimulating hormone (TSH) regulates thyroid hormone (TH) production via binding to its receptor (TSHR). The roles of TSHR in human pathologies including hyper/hypothyroidism, Grave’s disease, and thyroid cancer are known, but it is currently unknown whether TSHR is an imp...

  7. Optimization of growth hormone therapy in growth hormone deficient children

    NARCIS (Netherlands)

    S.M.P.F. de Muinck Keizer-Schrama (Sabine)

    1991-01-01

    textabstractIt is obvious that the results published so far as well as the present preliminary data do not answer many questions regarding the optimal therapeutic regimen in GH deficiency. In particular, long-term follow-up must be organized to evaluate efficacy and safety of GH therapy not only in

  8. Comparison of the in vitro effects of TCDD, PCB 126 and PCB 153 on thyroid-restricted gene expression and thyroid hormone secretion by the chicken thyroid gland.

    Science.gov (United States)

    Katarzyńska, Dorota; Hrabia, Anna; Kowalik, Kinga; Sechman, Andrzej

    2015-03-01

    The aim of this study was to compare the in vitro effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3,3',4,4',5-pentachlorobiphenyl (PCB 126; a coplanar PCB congener) and 2,2'4,4',5,5'-hexachlorobiphenyl (PCB153; non-coplanar PCB) on mRNA expression of thyroid-restricted genes, i.e. sodium iodide symporter (NIS), thyroid peroxidase (TPO) and thyroglobulin (TG), and thyroid hormone secretion from the thyroid gland of the laying chicken. Relative expression levels of NIS, TG and TPO genes and thyroxine (T4) and triiodothyronine (T3) secretion from the thyroidal explants were quantified by the real-time qPCR and RIA methods, respectively. In comparison with the control group, TCDD and PCB 126 significantly increased mRNA expression of TPO and TG genes. TCDD did not affect NIS mRNA levels, but PCB 126 decreased its expression. No effect of PCB 153 on the expression of these genes was observed. TCDD and PCB 126 significantly decreased T4 and T3 secretion. There was no significant effect of PCB 153 on these hormone secretions. In conclusion, the results obtained show that in comparison with non-coplanar PCB 153, TCDD and coplanar PCB 126 can directly affect thyroid hormone synthesis and secretion, and in consequence, they may disrupt the endocrine function of the thyroid gland of the laying chicken. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Growth hormone deficiency and hyperthermia during exercise

    DEFF Research Database (Denmark)

    Juul, A; Hjortskov, N; Jepsen, Leif

    1995-01-01

    -deficiency may be at risk for developing hyperthermia. To pursue this, we performed a controlled study on sweating and body temperature regulation during exercise in the heat in 16 GH-treated GH-deficient patients with normalized insulin-like growth factor-I and insulin-like growth factor/binding protein-3 serum.......001]. Consequently, the core temperatures of the patients increased significantly after exercise compared with those of the CTs [38.3 C (0.10 C) (MPD) and 38.1 C (0.06 C) (isolated GH deficiency) vs. 37.5 C (0.2 C) (CTs) (P temperature increased significantly during exercise in the patients...... but remained unaltered in the CTs. Sweat secretion rates, as determined by the pilocarpine method, were significantly lower in the MPD patients [77 (SE +/- 10) mg/30 min] than in the CTs [115 (SE +/- 7) mg/30 min] (P

  10. Adult Hippocampal Neurogenesis is Impaired by Transient and Moderate Developmental Thyroid Hormone Disruption

    Science.gov (United States)

    Severe thyroid hormone (TH) deprivation during development impairs neurogenesis throughout the brain. The hippocampus also maintains a capacity for neurogenesis throughout life which is reduced in adult-onset hypothyroidism. This study examined hippocampal volume in the neonate a...

  11. Computational Modeling of Thyroid Hormone Regulated Neurodevelopment for Chemical Prioritization (SOT)

    Science.gov (United States)

    Thyroid hormones (TH) are critical for normal brain development. Environmental chemicals may disrupt TH homeostasis through a variety of physiological systems including membrane transporters, serum transporters, synthesis and catabolic enzymes, and nuclear receptors. Current comp...

  12. Essential role of UCP1 modulating the central effects of thyroid hormones on energy balance

    Directory of Open Access Journals (Sweden)

    Mayte Alvarez-Crespo

    2016-04-01

    Conclusions: We conclude that UCP1 is essential for mediation of the central effects of thyroid hormones on energy balance, and we suggest that similar UCP1-dependent effects may underlie central energy balance effects of other agents.

  13. Mechanism-based testing strategy using in vitro approaches for identification of thyroid hormone disrupting chemicals

    Science.gov (United States)

    The thyroid hormone (TH) system is involved in several important physiological processes, including regulation of energy metabolism, growth and differentiation, development and maintenance of brain function, thermo-regulation, osmo-regulation, and axis of regulation of other endo...

  14. Effect of thyroid hormone replacement therapy on ovarian volume and androgen hormones in patients with untreated primary hypothyroidism.

    Science.gov (United States)

    Muderris, Iptisam Ipek; Boztosun, Abdullah; Oner, Gokalp; Bayram, Fahri

    2011-01-01

    Primary hypothyroidism may be associated with ovarian enlargement and/ or cyst formation. We evaluated the effect of thyroid hormone replacement therapy on hormonal changes, ovarian volume and sonographic appearance. Open, prospective study of women admitted to university gynecology clinic. The study included 26 patients with untreated hypothyroidism who had polycystic (n=10) or normal-appearing (n=16) ovaries and 20 euthyroidic controls. Basal serum total testosterone, free testosterone, androstenedione, dehydroepiandosterone-sulfate, prolactin, estradiol, luteinizing hormone, follicle-stimulating hormone, free T3, free T4 and thyroid-stimulating horone, together with ovarian volumes, were determined and repeated after euthyroidism was achieved. Ovarian volumes of patients with hypothyroidism were significantly greater compared with controls, and their magnitudes diminished significantly during thyroid hormone replacement therapy. Hypothyroidic patients with polycystic ovaries had significantly higher serum free testosterone and dehydroepiandosterone-sulfate, but lower androstenodione levels compared with those who had normal-appearing ovaries. Serum total testosterone concentrations were significantly higher in hypothyroidic patients without polycystic ovaries, and thyroid hormone replacement therapy achieved a significant reduction in total as well as free testosterone. Severe longstanding hypothyroidism leads to increased ovarian volume and/or cyst formation. A decrease in ovarian volume, resolution of ovarian cysts and reversal of the polycystic ovary syndrome-like appearance, together with improvement in serum hormone levels, occurred after euthyroidism was achieved.

  15. Duchenne muscular dystrophy with associated growth hormone deficiency

    International Nuclear Information System (INIS)

    Ghafoor, T.; Mahmood, A.; Shams, S.

    2003-01-01

    A patient with duchenne muscular dystrophy (DMD) and growth hormone (GH) deficiency is described who had no clinical evidence of muscular weakness before initiation of GH replacement therapy. Treatment with human GH resulted in appearance of symptoms of easy fatigability and muscle weakness. Thorough investigations including serum creating phosphokinase (CK) levels in recommended in every patient with GH deficiency before starting GH replacement therapy. (author)

  16. Effect of Growth Hormone Deficiency on Brain Structure, Motor Function and Cognition

    Science.gov (United States)

    Webb, Emma A.; O'Reilly, Michelle A.; Clayden, Jonathan D.; Seunarine, Kiran K.; Chong, Wui K.; Dale, Naomi; Salt, Alison; Clark, Chris A.; Dattani, Mehul T.

    2012-01-01

    The growth hormone-insulin-like growth factor-1 axis plays a role in normal brain growth but little is known of the effect of growth hormone deficiency on brain structure. Children with isolated growth hormone deficiency (peak growth hormone less than 6.7 [micro]g/l) and idiopathic short stature (peak growth hormone greater than 10 [micro]g/l)…

  17. Relationship between maternal thyroid hormones and the biochemical markers of the first trimester aneuploidy screening.

    Science.gov (United States)

    Aytan, Hakan; Caliskan, Ahmet C; Demirturk, Fazlı; Sahin, Semsettin; Erdogan, Filiz; Kuzu, Zehra

    2013-06-01

    The role of thyroid function in biochemical markers of first trimester screening has not been assessed. The aim of the present study was to investigate if there were any relation between maternal thyroid hormones and free-beta subunit of human chorionic gonadotropin (fβ-hCG) and pregnancy-associated plasma protein A (PAPP-A) levels as the biochemical markers of the combined first trimester aneuploidy screening. 375 pregnant women between 11 and 14 weeks of gestation who were offered routine first trimester prenatal aneuploidy screening and whose thyroid hormone levels (Thyroid stimulating hormone (TSH), free and total thyroxine, free and total triiodothyronine, anti thyroid peroxidase antibody) were measured were assessed. Correlation of free-β-hCG and PAPP-A with maternal thyroid hormones was analyzed. There was no statistically significant correlation between maternal TSH, free and total thyroxine, free and total triiodothyronine, anti-thyroid peroxidase antibodies and free-β-hCG and PAPP-A as biochemical markers of first trimester aneuploidy screening. Maternal thyroid function does not seem to affect secretion of fβ-hCG and PAPP-A.

  18. Functional neuroanatomy of thyroid hormone feedback in the human hypothalamus and pituitary gland

    NARCIS (Netherlands)

    Fliers, Eric; Unmehopa, Unga A.; Alkemade, Anneke

    2006-01-01

    A major change in thyroid setpoint regulation occurs in various clinical conditions such as critical illness and psychiatric disorders. As a first step towards identifying determinants of these setpoint changes, we have studied the distribution and expression of thyroid hormone receptor (TR)

  19. Association of the thyroid stimulating hormone receptor gene (TSHR) with Graves' disease

    DEFF Research Database (Denmark)

    Brand, Oliver J; Barrett, Jeffrey C; Simmonds, Matthew J

    2009-01-01

    Graves' disease (GD) is a common autoimmune disease (AID) that shares many of its susceptibility loci with other AIDs. The thyroid stimulating hormone receptor (TSHR) represents the primary autoantigen in GD, in which autoantibodies bind to the receptor and mimic its ligand, thyroid stimulating h...

  20. Analysis of thyroid hormones in gland and serum using liquid chromatography-tandem mass spectrometry

    Science.gov (United States)

    Thyroid hormones (THs), which are critical for growth and development in all vertebrates, can be impacted through chemical perturbation of the hypothalamic-pituitary-thyroid (HPT)-axis. Amphibian and mammalian models are being used to address this research priority within US EPA...

  1. Comparative study between the effects of replacement therapy with liquid and tablet formulations of levothyroxine on mood states, self-perceived psychological well-being and thyroid hormone profile in recently thyroidectomized patients.

    Science.gov (United States)

    Lombardi, Celestino Pio; Bocale, Raffaella; Barini, Angelina; Barini, Antonella; D'Amore, Annamaria; Boscherini, Mauro; Bellantone, Rocco

    2017-01-01

    Following thyroid surgery, levothyroxine therapy is used to replace deficient thyroid hormones and prevent postoperative thyroid hypofunction. We compared the effects of replacement therapy with either liquid or tablet formulation of levothyroxine on mood states, self-perceived mental well-being and thyroid hormone profile in recently thyroidectomized patients. Profile of mood states, General Heath Questionnaire 12-items and thyroid hormone profile were assessed in recently (5-7 days) thyroidectomized patients at baseline and 2 months after randomization to replacement therapy with either liquid (n = 77) or tablet (n = 78) formulation of levothyroxine. After 2 months under levothyroxine replacement treatment, significant improvements of Positive Affect Scale (p Profile of mood states, as well as of General Heath Questionnaire 12-items (p Profile of mood states, p = 0.030; Negative Affect Scale of Profile of mood states, p profile after 2 months of replacement therapy in recently thyroidectomized patients.

  2. The relationship between perchlorate in drinking water and cord blood thyroid hormones: First experience from Iran

    Directory of Open Access Journals (Sweden)

    Ashraf Javidi

    2015-01-01

    Full Text Available Background: Considering the controversial information regarding the effects of perchlorate on thyroid function of high risk population as neonates, and given the high prevalence rate of thyroid disorders specially congenital hypothyroidism in our region, this study aims to investigate for the first time in Iran, the relationship between drinking groundwater perchlorate and cord blood thyroid hormones level in an industrial region. Methods: In this cross-sectional study, drinking groundwater perchlorate level of rural areas of Zarinshahr, Isfahan was measured. Simultaneously, cord blood level of thyroid hormones of neonates born in the studied region was measured. Thyroid function test of neonates in regions with low and high perchlorate level were compared. Results: In this study, 25 tap water samples were obtained for perchlorate measurement. Level of cord blood thyroid stimulating hormone (TSH, T4 and T3 of 25 neonates were measured. Mean (standard deviation of perchlorate, TSH, T4 and T3 was 3.59 (5.10 μg/l, 7.81 (4.14 mIU/m, 6.06 (0.85 mg/dl, and 63.46 (17.53 mg/dl, respectively. Mean levels of thyroid function tests were not different in low ( 0.05. Conclusions: Perchlorate did not appear to be related to thyroid function of neonates in the studied industrial region. It seems that iodine status of the regions, as well as other environmental contaminants and genetic background, could impact on its relation with thyroid function of neonates.

  3. Placental Transfer of Perfluoroalkyl Substances and Associations with Thyroid Hormones: Beijing Prenatal Exposure Study

    Science.gov (United States)

    Yang, Lin; Li, Jingguang; Lai, Jianqiang; Luan, Hemi; Cai, Zongwei; Wang, Yibaina; Zhao, Yunfeng; Wu, Yongning

    2016-02-01

    Perfluoroalkyl substances (PFASs) have been detected in wildlife and human samples worldwide. Toxicology research showed that PFASs could interfere with thyroid hormone homeostasis. In this study, eight PFASs, fifteen PFAS precursors and five thyroid hormones were analyzed in 157 paired maternal and cord serum samples collected in Beijing around delivery. Seven PFASs and two precursors were detected in both maternal and cord sera with significant maternal-fetal correlations (r = 0.336 to 0.806, all P hormone (TSH) was negatively correlated with most maternal PFASs (r = -0.261 to -0.170, all P hormone homeostasis in humans.

  4. Perfluoroalkyl substances exposure and thyroid hormones in humans: epidemiological observations and implications

    Directory of Open Access Journals (Sweden)

    Jung Eun Lee

    2017-03-01

    Full Text Available Thyroid hormones play crucial roles in normal neurodevelopment of fetus and child. Many chemicals can affect control and homeostasis of thyroid hormones, and eventually lead to various adverse health effects including neurodevelopmental disorders. Perfluoroalkyl substances (PFASs are among the thyroid disrupting chemicals that can be encountered among general human population. Due to their unique physicochemical characteristics, PFASs have been used as surfactants and surface coating materials in many applications. Therefore, PFASs have been frequently detected in humans and environment worldwide. In cross-sectional studies using nationally representative general human populations of United States, several PFASs have shown significant associations with thyroid hormones. Moreover, among pregnant women and their infants, not only major PFASs such as perfluorooctane sulfonic acid and perfluorooctanoic acid, but also those with shorter or longer carbon chains showed significant associations with thyroid hormones. Often demographic characteristics such as sex, age, and disease status appear to influence the associations between PFASs exposure and thyroid hormones. In general, major PFASs showed hypothyroidism effects among pregnant women and infants. As 8 carbon based PFASs have been phased out, those with shorter or longer carbon chains have been used in growing amount as replacement. However, only limited information is available for their occurrences and toxicity among humans. Further investigations on these substituting PFASs are required. In addition, efforts are warranted to identify sources of and mitigate exposure to these thyroid disrupting chemicals especially during pregnancy and early stages of life.

  5. Thyroid hormone regulates reelin and dab1 expression during brain development

    OpenAIRE

    Alvarez-Dolado, Manuel; Ruiz, Mónica; Río Fernández, José Antonio del; Alcántara Horrillo, Soledad; Burgaya i Márquez, Ferran; Sheldon, Michael; Nakajima, Kazunori; Bernal, Juan; Howell, Brian W.; Curran, Tom

    1999-01-01

    The reelin and dab1 genes are necessary for appropriate neuronal migration and lamination during brain development. Since these processes are controlled by thyroid hormone, we studied the effect of thyroid hormone deprivation and administration on the expression of reelin anddab1. As shown by Northern analysis, in situ hybridization, and immunohistochemistry studies, hypothyroid rats expressed decreased levels of reelinRNA and protein during the perinatal period [embryonic day 18 (E18) and po...

  6. Regulation of fatty acid composition and lipid storage by thyroid hormone in mouse liver

    OpenAIRE

    Yao, Xuan; Hou, Sarina; Zhang, Duo; Xia, Hongfeng; Wang, Yu-Cheng; Jiang, Jingjing; Yin, Huiyong; Ying, Hao

    2014-01-01

    Background Thyroid hormones (THs) are potent hormones modulating liver lipid homeostasis. The perturbation of lipid homeostasis is a hallmark of non-alcoholic fatty liver disease (NAFLD), a very common liver disorder. It was reported that NAFLD patients were associated with higher incidence of hypothyroidism. However, whether abnormal thyroid function contributes to the pathogenesis of NAFLD remains unclear. Results We used in vivo models to investigate the influence of hypothyroidism and TH ...

  7. Paradigm Shift in Thyroid Hormone Mechanism of Action | Center for Cancer Research

    Science.gov (United States)

    Thyroid hormone (TH) is one of the primary endocrine regulators of human metabolism and homeostasis. Acting through three forms of the thyroid hormone receptor (THR; alpha-1, beta-1, and beta-2), TH regulates target gene expression in nearly every cell in the body, modulating fundamental processes, such as basal metabolic rate, long bone growth, and neural maturation. TH is also essential for proper development and differentiation of all cells of the human body.

  8. The involvement of thyroid hormones and cortisol in the osmotic acclimation of Solea senegalensis

    OpenAIRE

    Arjona, F.J.; Vargas-Chacoff, L.; Rio, M.P. Martin Del; Flik, G.; Mancera, J.M.; Klaren, P.H.M.

    2007-01-01

    The peripheral conversion of the prohormone 3,5,3',5'-tetraiodothyronine (T4) to the biologically active 3,5,3'-triiodothyronine (T3), via enzymatic deiodination by deiodinases, is an important pathway in thyroid hormone metabolism. The aim of this study was to test if thyroid hormones and cortisol, as well as the outer ring deiodination (ORD) metabolic pathway, are involved in the osmoregulatory response of Senegalese sole (Solea senegalensis, Kaup 1858). We measured osmoregulatory and endoc...

  9. An animal model of marginal iodine deficiency during development: The thyroid axis and neurodevelopmental outcome. ##

    Science.gov (United States)

    Thyroid hormones (TH) are essential for brain development and iodine is required for TH synthesis. Environmental chemicals that perturb the thyroid axis result in modest reductions in TH, yet there is a paucity of data on the extent of neurological impairments associated with low...

  10. An animal model of marginal iodine deficiency during development: The thyroid axis and neurodevelopmental outcome

    Science.gov (United States)

    Thyroid hormones (TH) are essential for brain development and iodine is required for TH synthesis. Environmental chemicals that perturb the thyroid axis result in modest reductions in TH, yet there is a paucity of data on the neurological impairments associated with low level TH ...

  11. Thyroid hormone resistance syndrome caused by heterozygous A317T mutation in thyroid hormone receptor β gene: Report of one Chinese pedigree and review of the literature.

    Science.gov (United States)

    Guo, Qing-Hua; Wang, Bao-An; Wang, Chen-Zhi; Wang, Min; Lu, Ju-Ming; Lv, Zhao-Hui; Mu, Yi-Ming

    2016-08-01

    Thyroid hormone resistance syndrome (THRS) is a rare disorder with increased concentrations of free thyroxine (FT4) and triiodothyronine (FT3), but normal or slightly increased thyroid-stimulating hormone (TSH). The mutations in the thyroid hormone receptor β (THRβ) gene are thought to be the main pathogenesis. The aims of this study were to present 1 pedigree of Chinese THRS, summarize their clinical characteristics, and analyze the gene mutation. The clinical characteristics and thyroid function of the proband and his family members were collected. Gene mutations were analyzed by DNA sequencing. The proband and his mother exhibited symptoms of hyperthyroidism, such as palpitations, heat intolerance, and perspiration. The mother also had atrial fibrillation. The rest of the kindred did not display clinical manifestations of hyper- or hypothyroidism. DNA sequencing revealed a heterozygous G>A missense mutation at position 949 in Exon 9 of THRβ both in the patient and his mother, which led to the transition from alanine to threonine at position 317 of THRβ protein (A317T), whereas the rest of the kindred did not share this mutation. The proband and his mother were diagnosed with pituitary resistance to thyroid hormone. Oral administration of methimazole was stopped and β-receptor blockers were administrated. We present 1 pedigree of THRS with heterozygous A317T mutation in THRβ gene in the proband and his mother, which is the first reported mutation in Chinese and provides a comprehensive review of available literature.

  12. Thyroid hormones and carcinoembryonic antigen in persons with a high risk of lung cancer

    International Nuclear Information System (INIS)

    Svetukhina, E.S.; Bukhteeva, N.F.; Sapozhkova, L.P.; Maripova, Eh.M.

    1984-01-01

    An attempt was made to study CEA and thyroid hormones in high risk groups as there is evidence of their change in lung cancer patients. A questionnaire to distinguish between 4 types of the probability of lung cancer development and a method of radioimmunoassay to study the concentration of CEA and thyroid hormones in the blood serum were used. A high risk group included 320 practically healthy persons, a control group 108 patients with verified lung cancer. The results of the study have shown that the concentration of CEA and thyroid hormones increases more often in persons of the high risk group with noncancerous diseases than in persons without pathological pulmonary changes. With an increase in the degree of probability the frequency of a high concentration of CEA and thyroid hormones grows. The older the persons with a high risk of lung cancer, the higher the frequency of concentration of the thyroid hormones. Studies of CEA and thyroid hormones can be used for dynamic observation of persons with a high risk of lung cancer

  13. Increased oxidative metabolism and neurotransmitter cycling in the brain of mice lacking the thyroid hormone transporter SLC16A2 (MCT8.

    Directory of Open Access Journals (Sweden)

    Tiago B Rodrigues

    Full Text Available Mutations of the monocarboxylate transporter 8 (MCT8 cause a severe X-linked intellectual deficit and neurological impairment. MCT8 is a specific thyroid hormone (T4 and T3 transporter and the patients also present unusual abnormalities in the serum profile of thyroid hormone concentrations due to altered secretion and metabolism of T4 and T3. Given the role of thyroid hormones in brain development, it is thought that the neurological impairment is due to restricted transport of thyroid hormones to the target neurons. In this work we have investigated cerebral metabolism in mice with Mct8 deficiency. Adult male mice were infused for 30 minutes with (1-(13C glucose and brain extracts prepared and analyzed by (13C nuclear magnetic resonance spectroscopy. Genetic inactivation of Mct8 resulted in increased oxidative metabolism as reflected by increased glutamate C4 enrichment, and of glutamatergic and GABAergic neurotransmissions as observed by the increases in glutamine C4 and GABA C2 enrichments, respectively. These changes were distinct to those produced by hypothyroidism or hyperthyroidism. Similar increments in glutamate C4 enrichment and GABAergic neurotransmission were observed in the combined inactivation of Mct8 and D2, indicating that the increased neurotransmission and metabolic activity were not due to increased production of cerebral T3 by the D2-encoded type 2 deiodinase. In conclusion, Mct8 deficiency has important metabolic consequences in the brain that could not be correlated with deficiency or excess of thyroid hormone supply to the brain during adulthood.

  14. Regulation of glucose transport by thyroid hormone in rat ovary.

    Science.gov (United States)

    Ding, Yu; Tian, Ye; Guo, Meng; Liu, Juan; Heng, Dai; Zhu, Baochang; Yang, Yanzhou; Zhang, Cheng

    2016-11-01

    Thyroid hormone (TH) plays an important role in regulating ovarian development. However, the mechanism involved remains unclear. Evidence suggests that glucose is essential for ovarian development, and its uptake is mediated by several glucose transporter proteins (Glut). We have investigated the effects of TH on Glut in rat ovary. Immature rats were treated with 6-propyl-2-thiouracil or L-thyroxine to induce hypothyroidism (hypo) or hyperthyroidism (hyper), respectively. Ovarian weights significantly decreased in both treated groups compared with the control group, although the body weights were not markedly altered. Glut1 expression significantly decreased without further changes being detected in the other Glut isforms in the hypo group and was accompanied by minimal change in mRNA content. The expression of Glut1 decreased in the hyper group. In contrast, L-thyroxine significantly increased Glut4 mRNA level and protein content but had little effect on Glut2 and Glut3 expression. Serum glucose concentrations in the hyper group were dramatically reduced compared with those in the control group. However, the serum glucose levels in the hypo group were not significantly changed. In addition, equine chorionic gonadotropin (eCG) increased ovarian weights in both the hypo and hyper groups compared with those in the rats without eCG injection. Glut2-4 protein content was significantly increased by eCG in hyper rats. Only the Glut4 mRNA content was significantly increased by eCG in the hyper group. Although the mRNA levels were not significantly changed by eCG in the hypo group, the protein level of Glut4 was markedly up-regulated. Serum glucose levels were not significantly altered by eCG in the two groups. Thus, dysfunction of the thyroid gland changes Glut expression in rat ovary and ovarian growth, both of which are also regulated by gonadotropin.

  15. Recalculation of thyroid doses after the Chernobyl accident in a iodine deficient area

    International Nuclear Information System (INIS)

    Olko, P.; Niewiadomski, T.; Budzanowski, M.; Szybinski, Z.

    1996-01-01

    The thyroid doses were estimated in Poland shortly after the Chernobyl accident with assumption of stable iodine consumption for the reference man and areas with ''standard'' stable iodine consumption. These estimates are not representative for southern part of Poland which is known as the iodine deficient area. Therefore the thyroid doses were recalculated based on the real and differentiated stable iodine intakes for people groups of different age without and with thyroid blockade after the accident. (author). 11 refs, 10 figs, 3 tabs

  16. Effects of sub-lethal heroin administration on thyroid stimulating hormone (TSH), thyroid hormones (T3, T4) and thyroid gland of Mus norvegicus.

    Science.gov (United States)

    Bhoir, Kaminidevi K; Suryawanshi, S A; Pandey, A K

    2009-11-01

    Serum TSH level of control Mus norvegicus fluctuated between 498.20 +/- 21.92 and 506.80 +/- 22.35 ng ml(-1), thyroxine (T4) between 68.17 +/- 3.46 and 69.03 +/- 4.12 microg dl(-1) and triiodothyronine (T3) between 4.76 +/- 0.52 and 5.00 +/- 0.66 microg dl(-1). Sub-lethal heroin administration induced a significant decline in the levels of all the three hormones at 24 hr and 15 days post-administration. Decline in the levels of these hormones registered the lowest values (pThyroid gland of control rat consisted of spherical, round follicles lined with low cuboidal and columnar epithelial cells and lumina filled with eosinophilic colloid. Ultrastructurally, the thyroid follicular cells showed the presence of round nuclei, polymorphic mitochondria, Golgi complex as well as lysosomes located on the apical side of the nucleus and cytoplasm with different sizes of lipid droplets and smooth along with rough endoplasmic reticulum. Basal lamina of the follicular cells was often in association with the endothelium of the capillaries. Sub-lethal heroin administration for 30 days elicited degenerative changes in the follicular epithelial cells as evident by the vacuolization of cytoplasm, pycnotic nuclei and reduced colloidal content. Ultrastructurally, the thyroid follicular cells showed indented nuclei with heavy deposition of chromatin material on the inner membrane of nucleus and dilated rough endoplasmic reticulum. Along with RBC infiltration, vesiculated mitochondria owing to the loss of cristae were also seen. Diffused electron-dense material was seen at the periphery of the cell body. Heroin treatment caused cellular necrosis as revealed by the fragmentation of cytoplasmic materials in follicular epithelial cells of the gland.

  17. Hypertrophic response of the Association of Thyroid Hormone and Exercise in the Heart of Rats

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Fernanda Rodrigues de, E-mail: nandaeduca@yahoo.com.br; Resende, Elmiro Santos; Lopes, Leandro; Gonçalves, Alexandre; Chagas, Rafaella; Fidale, Thiago; Rodrigues, Poliana [UFU - Universidade Federal de Uberlândia, Uberlândia, MG (Brazil)

    2014-02-15

    Cardiac hypertrophy is a component of cardiac remodeling occurring in response to an increase of the activity or functional overload of the heart. Assess hypertrophic response of the association of thyroid hormone and exercise in the rat heart. We used 37 Wistar rats, male, adults were randomly divided into four groups: control, hormone (TH), exercise (E), thyroid hormone and exercise (H + E); the group received daily hormone levothyroxine sodium by gavage at a dose of 20 μg thyroid hormone/100g body weight, the exercise group took swimming five times a week, with additional weight corresponding to 20% of body weight for six weeks; in group H + E were applied simultaneously TH treatment groups and E. The statistics used was analysis of variance, where appropriate, by Tukey test and Pearson correlation test. The T4 was greater in groups TH and H + E. The total weight of the heart was greater in patients who received thyroid hormone and left ventricular weight was greater in the TH group. The transverse diameter of cardiomyocytes increased in groups TH, E and H + E. The percentage of collagen was greater in groups E and H + E Correlation analysis between variables showed distinct responses. The association of thyroid hormone with high-intensity exercise produced cardiac hypertrophy, and generated a standard hypertrophy not directly correlated to the degree of fibrosis.

  18. Clinical study on the changes of perioperative serum thyroid hormone during heart surgery

    International Nuclear Information System (INIS)

    Xu Zhonghua; Qian Yongyue; Liu Zengli; Wu Jinchang; Yang Chen

    2002-01-01

    To observe the changes of perioperative serum thyroid hormone and their clinical significance, blood samples were obtained from 20 patients before, during and after heart operations. Thyroid hormones were measured by radioimmunoassay. The results showed that serum T 3 , T 4 and FT 3 levels significantly declined during cardiopulmonary bypass (CPB) and thereafter. Serum T 3 and T 4 concentrations reached their nadir at the lowest hypothermia of CPB. TSH and FT 4 levels remained normal ranges at postoperative sampling times. Conclusions: CPB would severely affect patients' thyroid function, thus simulated a 'low T 3 syndrome', and low T 3 syndrome would produce side effects on postoperative heart function

  19. Guidelines for the treatment of hypothyroidism: prepared by the american thyroid association task force on thyroid hormone replacement.

    Science.gov (United States)

    Jonklaas, Jacqueline; Bianco, Antonio C; Bauer, Andrew J; Burman, Kenneth D; Cappola, Anne R; Celi, Francesco S; Cooper, David S; Kim, Brian W; Peeters, Robin P; Rosenthal, M Sara; Sawka, Anna M

    2014-12-01

    A number of recent advances in our understanding of thyroid physiology may shed light on why some patients feel unwell while taking levothyroxine monotherapy. The purpose of this task force was to review the goals of levothyroxine therapy, the optimal prescription of conventional levothyroxine therapy, the sources of dissatisfaction with levothyroxine therapy, the evidence on treatment alternatives, and the relevant knowledge gaps. We wished to determine whether there are sufficient new data generated by well-designed studies to provide reason to pursue such therapies and change the current standard of care. This document is intended to inform clinical decision-making on thyroid hormone replacement therapy; it is not a replacement for individualized clinical judgment. Task force members identified 24 questions relevant to the treatment of hypothyroidism. The clinical literature relating to each question was then reviewed. Clinical reviews were supplemented, when relevant, with related mechanistic and bench research literature reviews, performed by our team of translational scientists. Ethics reviews were provided, when relevant, by a bioethicist. The responses to questions were formatted, when possible, in the form of a formal clinical recommendation statement. When responses were not suitable for a formal clinical recommendation, a summary response statement without a formal clinical recommendation was developed. For clinical recommendations, the supporting evidence was appraised, and the strength of each clinical recommendation was assessed, using the American College of Physicians system. The final document was organized so that each topic is introduced with a question, followed by a formal clinical recommendation. Stakeholder input was received at a national meeting, with some subsequent refinement of the clinical questions addressed in the document. Consensus was achieved for all recommendations by the task force. We reviewed the following therapeutic

  20. Guidelines for the Treatment of Hypothyroidism: Prepared by the American Thyroid Association Task Force on Thyroid Hormone Replacement

    Science.gov (United States)

    Bianco, Antonio C.; Bauer, Andrew J.; Burman, Kenneth D.; Cappola, Anne R.; Celi, Francesco S.; Cooper, David S.; Kim, Brian W.; Peeters, Robin P.; Rosenthal, M. Sara; Sawka, Anna M.

    2014-01-01

    Background: A number of recent advances in our understanding of thyroid physiology may shed light on why some patients feel unwell while taking levothyroxine monotherapy. The purpose of this task force was to review the goals of levothyroxine therapy, the optimal prescription of conventional levothyroxine therapy, the sources of dissatisfaction with levothyroxine therapy, the evidence on treatment alternatives, and the relevant knowledge gaps. We wished to determine whether there are sufficient new data generated by well-designed studies to provide reason to pursue such therapies and change the current standard of care. This document is intended to inform clinical decision-making on thyroid hormone replacement therapy; it is not a replacement for individualized clinical judgment. Methods: Task force members identified 24 questions relevant to the treatment of hypothyroidism. The clinical literature relating to each question was then reviewed. Clinical reviews were supplemented, when relevant, with related mechanistic and bench research literature reviews, performed by our team of translational scientists. Ethics reviews were provided, when relevant, by a bioethicist. The responses to questions were formatted, when possible, in the form of a formal clinical recommendation statement. When responses were not suitable for a formal clinical recommendation, a summary response statement without a formal clinical recommendation was developed. For clinical recommendations, the supporting evidence was appraised, and the strength of each clinical recommendation was assessed, using the American College of Physicians system. The final document was organized so that each topic is introduced with a question, followed by a formal clinical recommendation. Stakeholder input was received at a national meeting, with some subsequent refinement of the clinical questions addressed in the document. Consensus was achieved for all recommendations by the task force. Results: We reviewed the

  1. Effects of thyroid hormone on the GH signal transduction pathway.

    Science.gov (United States)

    Ocaranza, Paula; Lammoglia, Juan Javier; Iñiguez, Germán; Román, Rossana; Cassorla, Fernando

    2014-02-01

    The importance of thyroid hormone on growth and development in children is well recognized. In addition, linear growth is highly dependent on the response of peripheral tissues to growth hormone, a process known as GH sensitivity, but little is known about the possible effects of T4 on this process. We determined the effect of stimulation with recombinant human GH (rhGH; 200 ng/mL) alone or in combination with two different concentrations of T4 (250 nM and 500 nM for 24 h) on JAK2 and STAT5 activation in skin fibroblast cultures obtained from prepubertal boys with normal height. JAK2 and STAT5 were activated under co-incubation with T4 (at both concentrations) and rhGH in the non-nuclear fraction of the fibroblasts. In addition, after 24h of co-incubation with rhGH and T4 (500 nM), we observed an increase in phospho-STAT5 in the nuclear fraction, when compared to GH and T4 stimulation alone. This effect was not observed when the fibroblasts were co-incubated with GH and the lower concentration of T4 (250 nM). Combined stimulation with GH and T4 at a concentration of 500 nM increases synergistically nuclear phospho-STAT5 in skin fibroblasts, which may amplify tissue sensitivity to GH. These findings may help to explain the effect of T4 administration on growth velocity in some children with idiopathic short stature. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Gene specific actions of thyroid hormone receptor subtypes.

    Directory of Open Access Journals (Sweden)

    Jean Z Lin

    Full Text Available There are two homologous thyroid hormone (TH receptors (TRs α and β, which are members of the nuclear hormone receptor (NR family. While TRs regulate different processes in vivo and other highly related NRs regulate distinct gene sets, initial studies of TR action revealed near complete overlaps in their actions at the level of individual genes. Here, we assessed the extent that TRα and TRβ differ in target gene regulation by comparing effects of equal levels of stably expressed exogenous TRs +/- T(3 in two cell backgrounds (HepG2 and HeLa. We find that hundreds of genes respond to T(3 or to unliganded TRs in both cell types, but were not able to detect verifiable examples of completely TR subtype-specific gene regulation. TR actions are, however, far from identical and we detect TR subtype-specific effects on global T(3 response kinetics in HepG2 cells and many examples of TR subtype specificity at the level of individual genes, including effects on magnitude of response to TR +/- T(3, TR regulation patterns and T(3 dose response. Cycloheximide (CHX treatment confirms that at least some differential effects involve verifiable direct TR target genes. TR subtype/gene-specific effects emerge in the context of widespread variation in target gene response and we suggest that gene-selective effects on mechanism of TR action highlight differences in TR subtype function that emerge in the environment of specific genes. We propose that differential TR actions could influence physiologic and pharmacologic responses to THs and selective TR modulators (STRMs.

  3. Deafness and loss of cochlear hair cells in the absence of thyroid hormone transporters Slc16a2 (Mct8) and Slc16a10 (Mct10).

    Science.gov (United States)

    Sharlin, David S; Ng, Lily; Verrey, François; Visser, Theo J; Liu, Ye; Olszewski, Rafal T; Hoa, Michael; Heuer, Heike; Forrest, Douglas

    2018-03-13

    Transmembrane proteins that mediate the cellular uptake or efflux of thyroid hormone potentially provide a key level of control over neurodevelopment. In humans, defects in one such protein, solute carrier SLC16A2 (MCT8) are associated with psychomotor retardation. Other proteins that transport the active form of thyroid hormone triiodothyronine (T3) or its precursor thyroxine (T4) have been identified in vitro but the wider significance of such transporters in vivo is unclear. The development of the auditory system requires thyroid hormone and the cochlea is a primary target tissue. We have proposed that the compartmental anatomy of the cochlea would necessitate transport mechanisms to convey blood-borne hormone to target tissues. We report hearing loss in mice with mutations in Slc16a2 and a related gene Slc16a10 (Mct10, Tat1). Deficiency of both transporters results in retarded development of the sensory epithelium similar to impairment caused by hypothyroidism, compounded with a progressive degeneration of cochlear hair cells and loss of endocochlear potential. Administration of T3 largely restores the development of the sensory epithelium and limited auditory function, indicating the T3-sensitivity of defects in the sensory epithelium. The results indicate a necessity for thyroid hormone transporters in cochlear development and function.

  4. Comparison of therapeutic efficacy and clinical parameters between recombinant human thyroid stimulating hormone and thyroid hormone withdrawal in high-dose radioiodine treatment with differentiated thyroid cancer

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Se Hun; Na, Chang Ju; Kim, Jeong Hun; Han, Yeon Hee; KIm, Hee Kwon; Jeong, Hwan Jeong; Sohn, Myung Hee; Lim, Seok Tae [Dept. of Nuclear Medicine, Chonbuk National University Medical School and Hospital, Jeonju (Korea, Republic of)

    2015-06-15

    High-dose radioiodine treatment (HD-RIT) after injection of recombinant human thyroid stimulating hormone (rh-TSH) has become widely used. This study compared the therapeutic efficacy of HD-RIT and clinical parameters between rh-TSH supplement and thyroid hormone withdrawal (THW) after total thyroidectomy in patients with differentiated thyroid cancer. We retrospectively reviewed 266 patients (47 male and 219 female; age, 49.0 ± 10.9 years) with differentiated thyroid cancer detected from September 2011 to September 2012. Patients comprised THW (217, 81.6 %) and rh-TSH (49, 18.4 %). Inclusion criteria were: first HD-RIT; any TN stage; absence of distant metastasis. To evaluate the complete ablation of the remnant thyroid tissue or metastasis, we reviewed stimulated serum thyroglobulin (sTg), I-123 whole-body scan (RxWBS) on T4 off-state, and thyroid ultrasonography (US) or [F-18]-fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) 6–8 months after HD-RIT. We defined a complete ablation state when all three of the follow-up conditions were satisfied; <2.0 ng/ml of the sTg, I-123 RxWBS (−), and thyroid US or F-18 FDG PET/CT (−). If one of the three was positive, ablation was considered incomplete. We also compared various clinical biomarkers (body weight, body mass index, liver and kidney function) between THW and rh-TSH groups. The rates of complete ablation were 73.7 % (160/217) for the THW group and 73.5 % (36/49) for the rh-TSH group. There was no significant difference between the two groups (p = 0.970). The follow-up aspartate transaminase (p = 0.001) and alanine transaminase (p = 0.001) were significantly higher in the THW group. The renal function parameters of blood urea nitrogen (p = 0.001) and creatinine (p = 0.005) tended to increase in the THW group. The change of body weight was + Δ0.96 (±1.9) kg for the THW group and was decreased by -Δ1.39 (±1.5) kg for the rh-TSH group. The change

  5. Differential regulation of thyrotropin subunit apoprotein and carbohydrate biosynthesis by thyroid hormone

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, T.; Weintraub, B.D.

    1985-04-01

    The regulation of TSH apoprotein and carbohydrate biosynthesis by thyroid hormone was studied by incubating pituitaries from normal and hypothyroid (3 weeks post-thyroidectomy) rats in medium containing (/sup 14/C)alanine and (/sup 3/H) glucosamine. After 6 h, samples were sequentially treated with anti-TSH beta to precipitate TSH and free TSH beta, anti-LH beta to clear the sample of LH and free LH beta, then anti-LH alpha to precipitate free alpha-subunit. Total proteins were acid precipitated. All precipitates were subjected to electrophoresis on sodium dodecyl sulfate-polyacrylamide gels, which were then sliced and assayed by scintillation spectrometry. In hypothyroid pituitaries plus medium, (/sup 14/C)alanine incorporation in combined and free beta-subunits was 26 times normal and considerably greater than the 3.4-fold increase seen in total protein; combined and free alpha-subunits showed no specific increase in apoprotein synthesis. (/sup 3/H)Glucosamine incorporation in combined alpha- and beta-subunits in hypothyroid samples was 13 and 21 times normal, respectively, and was greater than the 1.9-fold increase in total protein; free alpha-subunit showed no specific increase in carbohydrate synthesis. The glucosamine to alanine ratio, reflecting relative glycosylation of newly synthesized molecules, was increased in hypothyroidism for combined alpha-subunits, but not for combined beta-subunits, free alpha-subunits, or total proteins. In summary, short term hypothyroidism selectively stimulated TSH beta apoprotein synthesis and carbohydrate synthesis of combined alpha- and beta-subunits. Hypothyroidism also increased the relative glycosylation of combined alpha-subunit. Thus, thyroid hormone deficiency appears to alter the rate-limiting step in TSH assembly (i.e. beta-subunit synthesis) as well as the carbohydrate structure of TSH, which may play important roles in its biological function.

  6. Thyroid hormone responsive QTL and the evolution of paedomorphic salamanders.

    Science.gov (United States)

    Voss, S R; Kump, D K; Walker, J A; Shaffer, H B; Voss, G J

    2012-11-01

    The transformation of ancestral phenotypes into novel traits is poorly understood for many examples of evolutionary novelty. Ancestrally, salamanders have a biphasic life cycle with an aquatic larval stage, a brief and pronounced metamorphosis, followed by a terrestrial adult stage. Repeatedly during evolution, metamorphic timing has been delayed to exploit growth-permissive environments, resulting in paedomorphic salamanders that retain larval traits as adults. We used thyroid hormone (TH) to rescue metamorphic phenotypes in paedomorphic salamanders and then identified quantitative trait loci (QTL) for life history traits that are associated with amphibian life cycle evolution: metamorphic timing and adult body size. We demonstrate that paedomorphic tiger salamanders (Ambystoma tigrinum complex) carry alleles at three moderate effect QTL (met1-3) that vary in responsiveness to TH and additively affect metamorphic timing. Salamanders that delay metamorphosis attain significantly larger body sizes as adults and met2 explains a significant portion of this variation. Thus, substitution of alleles at TH-responsive loci suggests an adaptive pleiotropic basis for two key life-history traits in amphibians: body size and metamorphic timing. Our study demonstrates a likely pathway for the evolution of novel paedomorphic species from metamorphic ancestors via selection of TH-response alleles that delay metamorphic timing and increase adult body size.

  7. Thyroid hormone promotes remodeling of coronary resistance vessels.

    Directory of Open Access Journals (Sweden)

    Olga V Savinova

    Full Text Available Low thyroid hormone (TH function has been linked to impaired coronary blood flow, reduced density of small arterioles, and heart failure. Nonetheless, little is known about the mechanisms by which THs regulate coronary microvascular remodeling. The current study examined the initial cellular events associated with coronary remodeling induced by triiodothyronine (T3 in hypothyroid rats. Rats with established hypothyroidism, eight weeks after surgical thyroidectomy (TX, were treated with T3 for 36 or 72 hours. The early effects of T3 treatment on coronary microvasculature were examined morphometrically. Gene expression changes in the heart were assessed by quantitative PCR Array. Hypothyroidism resulted in arteriolar atrophy in the left ventricle. T3 treatment rapidly induced small arteriolar muscularization and, within 72 hours, restored arteriolar density to control levels. Total length of the capillary network was not affected by TX or T3 treatment. T3 treatment resulted in the coordinate regulation of Angiopoietin 1 and 2 expression. The response of Angiopoietins was consistent with vessel enlargement. In addition to the well known effects of THs on vasoreactivity, these results suggest that THs may affect function of small resistance arteries by phenotypic remodeling of vascular smooth muscle cells (VSMC.

  8. Effect of thimerosal on thyroid hormones metabolism in rats

    Directory of Open Access Journals (Sweden)

    Thiago U Pantaleão

    2017-11-01

    Full Text Available Mercury seems to exert an inhibitory effect on deiodinases, but there are few studies using Thimerosal (TM as the mercury source. We aimed to elucidate the effect of TM on thyroid hormones peripheral metabolism. Adult Wistar female rats received 0.25 μg or 250 μg TM/100 g BW, IM, twice a week, for a month. We evaluated serum total T3 and T4, D1 activity using 125I-rT3 as tracer, and D2 activity using 125I-T4. NADPH oxidase activity was measured by Amplex-red/HRP method and mRNA levels by real time PCR. Serum T4 was increased and T3 decreased by the greatest dose of TM. Even though D1 activity in pituitary and kidney was reduced by the highest dose of TM, hepatic D1 activity and D1 mRNA levels remained unchanged. D2 activity was also significantly decreased by the highest dose of TM in all CNS samples tested, except cerebellum, but D2 mRNA was unaltered. mRNA levels of the tested NADPH oxidases were not affected by TM and NADPH oxidase activity was either unaltered or decreased. Our results indicate that TM might directly interact with deiodinases, inhibiting their activity probably by binding to their selenium catalytic site, without changes in enzyme expression.

  9. Thyroid stimulating hormone increases hepatic gluconeogenesis via CRTC2.

    Science.gov (United States)

    Li, Yujie; Wang, Laicheng; Zhou, Lingyan; Song, Yongfeng; Ma, Shizhan; Yu, Chunxiao; Zhao, Jiajun; Xu, Chao; Gao, Ling

    2017-05-05

    Epidemiological evidence indicates that thyroid stimulating hormone (TSH) is positively correlated with abnormal glucose levels. We previously reported that TSH has direct effects on gluconeogenesis. However, the underlying molecular mechanism remains unclear. In this study, we observed increased fasting blood glucose and glucose production in a mouse model of subclinical hypothyroidism (only elevated TSH levels). TSH acts via the classical cAMP/PKA pathway and CRTC2 regulates glucose homeostasis. Thus, we explore whether CRTC2 is involved in the process of TSH-induced gluconeogenesis. We show that TSH increases CRTC2 expression via the TSHR/cAMP/PKA pathway, which in turn upregulates hepatic gluconeogenic genes. Furthermore, TSH stimulates CRTC2 dephosphorylation and upregulates p-CREB (Ser133) in HepG2 cells. Silencing CRTC2 and CREB decreases the effect of TSH on PEPCK-luciferase, the rate-limiting enzyme of gluconeogenesis. Finally, the deletion of TSHR reduces the levels of the CRTC2:CREB complex in mouse livers. This study demonstrates that TSH activates CRTC2 via the TSHR/cAMP/PKA pathway, leading to the formation of a CRTC2:CREB complex and increases hepatic gluconeogenesis. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Thyroiditis

    Science.gov (United States)

    ... Anaplastic Thyroid Cancer Complementary and Alternative Medicine in Thyroid Disease FNA Biopsy of Thyroid Nodules Goiter Graves’ Disease ... Cancer Nuclear Radiation & the Thyroid Older Patients and Thyroid Disease Papillary & Follicular Thyroid Cancer Postpartum Thyroiditis Pregnancy and ...

  11. Chemical Hybridization of Glucagon and Thyroid Hormone Optimizes Therapeutic Impact for Metabolic Disease

    DEFF Research Database (Denmark)

    Finan, Brian; Clemmensen, Christoffer; Zhu, Zhimeng

    2016-01-01

    Glucagon and thyroid hormone (T3) exhibit therapeutic potential for metabolic disease but also exhibit undesired effects. We achieved synergistic effects of these two hormones and mitigation of their adverse effects by engineering chemical conjugates enabling delivery of both activities within on...

  12. Functional analysis of novel genetic variation in the thyroid hormone activating type 2 deiodinase

    NARCIS (Netherlands)

    C. Zevenbergen (Chantal); W. Klootwijk (Willem); R.P. Peeters (Robin); M. Medici (Marco); Y.B. de Rijke (Yolanda); S.A. Huisman (Sylvia); Goeman, H. (Henk); Boot, E. (Erik); G. Kuijper (Gerda); K.H. de Waal; M.E. Meima (Marcel); P.R. Larsen (Reed); T.J. Visser (Theo); W.E. Visser (Wil Edward)

    2014-01-01

    markdownabstractContext: Thyroid hormones (TH) are important for normal brain development and abnormal TH regulation in the brain results in neurocognitive impairments. The type 2 deiodinase (D2) is important for local TH control in the brain by generating the active hormone T3 from its precursor

  13. Effect of 4 weeks of octreotide treatment on prolactin, thyroid stimulating hormone and thyroid hormones in acromegalic patients. A double blind placebo-controlled cross-over study

    DEFF Research Database (Denmark)

    Andersen, M; Hansen, T B; Bollerslev, J

    1995-01-01

    We aimed to test the hypothesis, that octreotide has a suppressive effect on unstimulated and TRH-stimulated PRL levels in both normo- and hyperprolactinaemic acromegalic patients, and besides to evaluate the effect of octreotide on unstimulated TSH and thyroid hormones. The present study is a do...

  14. Action of Specific Thyroid Hormone Receptor alpha(1) and beta(1) Antagonists in the Central and Peripheral Regulation of Thyroid Hormone Metabolism in the Rat

    NARCIS (Netherlands)

    van Beeren, Hermina C.; Kwakkel, Joan; Ackermans, Mariëtte T.; Wiersinga, Wilmar M.; Fliers, Eric; Boelen, Anita

    2012-01-01

    Background: The iodine-containing drug amiodarone (Amio) and its noniodine containing analogue dronedarone (Dron) are potent antiarrhythmic drugs. Previous in vivo and in vitro studies have shown that the major metabolite of Amio, desethylamiodarone, acts as a thyroid hormone receptor (TR) alpha(1)

  15. Mild Thyroid Hormone Insufficiency During Development Compromises Activity-Dependent Neuroplasticity in the Hippocampus of Adult Male Rats

    Data.gov (United States)

    U.S. Environmental Protection Agency — behavioral measures of learning and memory in adult offspring of rats treated with thyroid hormone synthesis inhibitor, propylthiouracil. Electrophysiological...

  16. Impaired thermoregulation in adults with growth hormone deficiency during heat exposure and exercise

    DEFF Research Database (Denmark)

    Juul, A; Behrenscheer, A; Tims, T

    1993-01-01

    It has recently been shown that patients with growth hormone deficiency have a reduced sweating capacity. We hypothesize that reduced sweating might affect thermoregulation in growth hormone deficiency patients. In the present study we have examined thermoregulation in growth hormone deficiency...

  17. Iodine Deficiency

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2009-01-01

    Iodine deficiency has multiple adverse effects in humans, termed iodine deficiency disorders, due to inadequate thyroid hormone production. Globally, it is estimated that 2 billion individuals have an insufficient iodine intake, and South Asia and sub-Saharan Africa are particularly affected.

  18. Internal and external quality control in the determinations of the thyroid hormones

    International Nuclear Information System (INIS)

    Rodriguez, S.; Richmond, M.; Gonzalez, L.; Saenz, E.

    1990-01-01

    An evaluation of the thyroid hormone level in young adults and the results of an External Quality Control (EQC) for the thyroid related hormones: Thyroxine (T4), Triidothyronine (T3) and Thyroid Stinulating Hormone (TSH) are presented for Costa Rica. Hormone level in the 1053 sera evaluated range 0,2 to 3,52 nmol/1, from 43 to 207 nmol/1, and from 0 to 6,2 uUl/ml, for the nine radioimmunoassay laboratories that participated in the EQC. The mean variability among laboratories was 19.3%, 18% and 20.5% for T3, T4 and TSH, respectively. The Internal Quality Control (IQC) in the reference laboratory (immunoassay, INCIENSA) showed a mean variability of 5.6%, 6.22% and 6.93% for T3, T4 and TSH, respectively. (author). 19 refs, 4 figs

  19. Thyroid hormone and retinoic acid nuclear receptors: specific ligand-activated transcription factors

    International Nuclear Information System (INIS)

    Brtko, J.

    1998-01-01

    Transcriptional regulation by both the thyroid hormone and the vitamin A-derived 'retinoid hormones' is a critical component in controlling many aspects of higher vertebrate development and metabolism. Their functions are mediated by nuclear receptors, which comprise a large super-family of ligand-inducible transcription factors. Both the thyroid hormone and the retinoids are involved in a complex arrangement of physiological and development responses in many tissues of higher vertebrates. The functions of 3,5,3'-triiodothyronine (T 3 ), the thyromimetically active metabolite of thyroxine as well as all-trans retinoic acid, the biologically active vitamin A metabolite are mediated by nuclear receptor proteins that are members of the steroid/thyroid/retinoid hormone receptor family. The functions of all members of the receptor super family are discussed. (authors)

  20. Anthropometric measurements in patients with growth hormone deficiency before treatment with human growth hormone.

    Science.gov (United States)

    Zachmann, M; Fernandez, F; Tassinari, D; Thakker, R; Prader, A

    1980-05-01

    In 74 children (52 males, 22 females) with growth hormone (GH) deficiency (30 cases with isolated GH-deficiency, two of them familial; 4 familial and one isolated case with tendency for formation of antibodies against hGH; 29 with other pituitary hormone defects; 10 craniopharyngiomas), various anthropometric measurements were analyzed before treatment with hGH. In all groups, standing height, sitting height, and subischial leg height were equally retarded, and bihumeral width was more retarded than biiliac width; the head was relatively large; fat tissue was increased with subscapular skinfolds being greater than triceps skinfolds, indicating relative obestiy of the trunk; muscle and/or bone mass was reduced. In isolated GH-deficiency, head shape was slightly scaphoid; in combined defects, it was round, and in craniopharyngioma cases, it was brachycephalic. It is concluded that antrhopometric measurements may help in differentiating the type of GH-deficiency.

  1. Action of specific thyroid hormone receptor α(1) and β(1) antagonists in the central and peripheral regulation of thyroid hormone metabolism in the rat.

    Science.gov (United States)

    van Beeren, Hermina C; Kwakkel, Joan; Ackermans, Mariëtte T; Wiersinga, Wilmar M; Fliers, Eric; Boelen, Anita

    2012-12-01

    The iodine-containing drug amiodarone (Amio) and its noniodine containing analogue dronedarone (Dron) are potent antiarrhythmic drugs. Previous in vivo and in vitro studies have shown that the major metabolite of Amio, desethylamiodarone, acts as a thyroid hormone receptor (TR) α(1) and β(1) antagonist, whereas the major metabolite of Dron debutyldronedarone acts as a selective TRα(1) antagonist. In the present study, Amio and Dron were used as tools to discriminate between TRα(1) or TRβ(1) regulated genes in central and peripheral thyroid hormone metabolism. Three groups of male rats received either Amio, Dron, or vehicle by daily intragastric administration for 2 weeks. We assessed the effects of treatment on triiodothyronine (T(3)) and thyroxine (T(4)) plasma and tissue concentrations, deiodinase type 1, 2, and 3 mRNA expressions and activities, and thyroid hormone transporters monocarboxylate transporter 8 (MCT8), monocarboxylate transporter 10 (MCT10), and organic anion transporter 1C1 (OATP1C1). Amio treatment decreased serum T(3), while serum T(4) and thyrotropin (TSH) increased compared to Dron-treated and control rats. At the central level of the hypothalamus-pituitary-thyroid axis, Amio treatment decreased hypothalamic thyrotropin releasing hormone (TRH) expression, while increasing pituitary TSHβ and MCT10 mRNA expression. Amio decreased the pituitary D2 activity. By contrast, Dron treatment resulted in decreased hypothalamic TRH mRNA expression only. Upon Amio treatment, liver T(3) concentration decreased substantially compared to Dron and control rats (50%, p<0.01), but liver T(4) concentration was unaffected. In addition, liver D1, mRNA, and activity decreased, while the D3 activity and mRNA increased. Liver MCT8, MCT10, and OATP1C1 mRNA expression were similar between groups. Our results suggest an important role for TRα1 in the regulation of hypothalamic TRH mRNA expression, whereas TRβ plays a dominant role in pituitary and liver thyroid

  2. Growth hormone deficiency in children with brain tumors

    International Nuclear Information System (INIS)

    Shalet, S.M.; Beardwell, C.G.; Morris-Jones, P.; Bamford, F.N.; Ribeiro, G.G.; Pearson, D.

    1976-01-01

    Nine children with brain tumors are described who have received various combinations of treatment, including surgery, radiotherapy, and chemotherapy. Many of the children were noted to be of short stature. Endocrine assessment was carried out from 2 to 10 years after treatment. The combined results of insulin tolerance and Bovril stimulation tests show an impaired growth hormone response in six of the nine children. Bone age is retarded in all cases, and the present height is below the 10th percentile in five of the six. The cause of this growth hormone deficiency is obscure, but further studies are in progress

  3. [Nanism caused by water deprivation, with transitory growth hormone deficiency].

    Science.gov (United States)

    Beauvais, P; Debard, A; Brissaud, H E

    1975-10-01

    Report of a case of a girl admitted for alcoholic poisoning then for a toxic syndrome with considerable hypernatremia. Clinical examination showed a dwarfism (-4 S.D.) with break of the growth curve and bone-age retardation. History revealed cruelty and thirsting since the age of 2 years. Isolated somatotropin insufficiency was found. Separation from the family and free drinking induced a spectacular recovery of growth and normalization of growth hormone level. The relative role and relationships between growth hormone deficiency and chronic dehydration due to water deprivation in the physiopathology of dwarfism due to frustration are discussed.

  4. Subacute microcystin-LR exposure alters the metabolism of thyroid hormones in juvenile zebrafish (Danio Rerio).

    Science.gov (United States)

    Liu, Zidong; Tang, Rong; Li, Dapeng; Hu, Qing; Wang, Ying

    2015-01-30

    Microcystin-LR (MC-LR) has been detected extensively in the aquatic environment and has the potential to disturb the thyroid endocrine system. However, limited information is available on the effects of subacute MC-LR exposure on fish thyroid hormone (TH) metabolism. In the present study, juvenile zebrafish (Danio rerio) were exposed to MC-LR at environmentally relevant concentrations (0, 1, 5, and 25 μg/L) for 28 days. Whole-body TH content and thyroid follicle histology were used as direct endpoints to assess thyroid disruption. The activities of iodothyronine deiodinases (IDs) and the transcription of selected genes associated with TH synthesis were also investigated to study the underlying mechanisms of endocrine disruption. Exposure of zebrafish to MC-LR significantly increased whole-body thyroxine (T4) content but decreased whole-body triiodothyronine (T3) content. We also observed hypertrophy and hyperplasia of the thyroid follicle epithelial cells, as well as up-regulation of corticotropin-releasing hormone (CRH), thyroid-stimulating hormone (TSH), thyroid peroxidase (TPO), and transthyretin (TTR) genes. The decreases in ID1 and ID2 activities coupled with an increase in ID3 activity were observed in MC-LR treatment groups. These results demonstrate that exposure to MC-LR at environmental concentrations results in the disturbance of TH homeostasis by disrupting the synthesis and conversion of THs.

  5. Subacute Microcystin-LR Exposure Alters the Metabolism of Thyroid Hormones in Juvenile Zebrafish (Danio Rerio

    Directory of Open Access Journals (Sweden)

    Zidong Liu

    2015-01-01

    Full Text Available Microcystin-LR (MC-LR has been detected extensively in the aquatic environment and has the potential to disturb the thyroid endocrine system. However, limited information is available on the effects of subacute MC-LR exposure on fish thyroid hormone (TH metabolism. In the present study, juvenile zebrafish (Danio rerio were exposed to MC-LR at environmentally relevant concentrations (0, 1, 5, and 25 μg/L for 28 days. Whole-body TH content and thyroid follicle histology were used as direct endpoints to assess thyroid disruption. The activities of iodothyronine deiodinases (IDs and the transcription of selected genes associated with TH synthesis were also investigated to study the underlying mechanisms of endocrine disruption. Exposure of zebrafish to MC-LR significantly increased whole-body thyroxine (T4 content but decreased whole-body triiodothyronine (T3 content. We also observed hypertrophy and hyperplasia of the thyroid follicle epithelial cells, as well as up-regulation of corticotropin-releasing hormone (CRH, thyroid-stimulating hormone (TSH, thyroid peroxidase (TPO, and transthyretin (TTR genes. The decreases in ID1 and ID2 activities coupled with an increase in ID3 activity were observed in MC-LR treatment groups. These results demonstrate that exposure to MC-LR at environmental concentrations results in the disturbance of TH homeostasis by disrupting the synthesis and conversion of THs.

  6. BRAFV600Emutation contributes papillary thyroid carcinoma and Hashimoto thyroiditis with resistance to thyroid hormone: A case report and literature review.

    Science.gov (United States)

    Xing, Wanjia; Liu, Xiaohong; He, Qingqing; Zhang, Zongjing; Jiang, Zhaoshun

    2017-09-01

    Resistance to thyroid hormone (RTH) is a rare autosomal hereditary disorder characterized by increased serum thyroid hormone (TH) levels with unsuppressed or increased thyrotropin concentration. It remains unknown whether the coexistence of RTH with papillary thyroid carcinoma (PTC) and Hashimoto thyroiditis (HT) is incidental or whether it possesses a genetic or pathophysiological association. In the present study, a case of RTH with PTC and HT in an 11-year-old Chinese patient was examined and the clinical presentation of RTH with PTC was discussed. In addition, the possible associations between RTH, PTC and HT were determined. HT was confirmed in the patient using an autoimmune assay and thyroid ultrasound. RTH was diagnosed on the basis of clinical manifestations, laboratory information and gene analysis, and PTC was diagnosed according to histological results. Results of BRAF V600E mutation analysis were positive. A literature review of 14 cases of RTH with PTC was included for comparison. The present case report indicates an association of RTH with PTC and HT coexistence in the patient. Close follow-up, histological evaluation and BRAF V600E mutation detection should be performed in each RTH case with HT, since a persistent increase in TSH may be a risk factor for the development of thyroid neoplasm.

  7. In Vitro, Ex Vivo, and In Vivo Determination of Thyroid Hormone Modulating Activity of Benzothiazoles.

    Science.gov (United States)

    Hornung, Michael W; Kosian, Patricia A; Haselman, Jonathan T; Korte, Joseph J; Challis, Katie; Macherla, Chitralekha; Nevalainen, Erica; Degitz, Sigmund J

    2015-08-01

    As in vitro assays are increasingly used to screen chemicals for their potential to produce endocrine disrupting adverse effects, it is important to understand their predictive capacity. The potential for a set of 6 benzothiazoles to affect endpoints related to thyroid hormone synthesis inhibition were assessed using in vitro, ex vivo, and in vivo assays. Inhibition of thyroid peroxidase (TPO) derived from pig thyroid glands was determined for benzothiazole (BTZ), 2-mercaptobenzothiazole (MBT), 5-chloro-2-mercaptobenzothiazole (CMBT), 2-aminobenzothiazole (ABT), 2-hydroxybenzothiazole (HBT), and 2-methylthiobenzothiazole (MTBT). Their rank order potency for TPO inhibition was MBT=CMBT>ABT>BTZ, whereas HBT and MTBT exhibited no inhibitory activity. The benzothiazoles were tested further in a Xenopus laevis thyroid gland explant culture assay in which inhibition of thyroxine (T4) release was the measured endpoint. In this assay all 6 benzothiazoles inhibited T4 release. The activity of the benzothiazoles for disrupting thyroid hormone activity was verified in vivo using X. laevis tadpoles in a 7-day assay. The 2 most potent chemicals for TPO inhibition, MBT and CMBT, produced responses in vivo indicative of T4 synthesis inhibition including induction of sodium iodide symporter mRNA and decreases in glandular and circulating thyroid hormones. The capability to measure thyroid hormone levels in the glands and blood by ultrahigh performance LC-MS/MS methods optimized for small tissue samples was critical for effects interpretation. These results indicate that inhibition of TPO activity in vitro was a good indicator of a chemical's potential for thyroid hormone disruption in vivo and may be useful for prioritizing chemicals for further investigation. Published by Oxford University Press on behalf of the Society of Toxicology 2015. This work is written by US Government employees and is in the public domain in the US.

  8. [Thyroid gland pathology in children population exposed to the combination of iodine deficiency and fluoride pollution of environment].

    Science.gov (United States)

    Savchenkov, M F; Efimova, N V; Manueva, R S; Nikolaeva, L A; Shin, N S

    The article presents results of study of the impact of iodine deficiency and technogenic fluoride on the state of the thyroid gland in children. On the example of two districts of the city of Bratsk there were executed dynamic investigations (2002 and 2012), including the estimation of the pollution of ambient air and soil by fluorine compounds, levels of iodine intake by the body, the clinical examination of children aged from 5 to 7 years d and interviewing of their parents. In the course of the medical examination there were executed: physical examination by the pediatrician, endocrinologist, ultrasound examination of the thyroid gland, the determination both of serum hormone content by radioimmunoassay and urinary excretion offluorine and iodine. Concentrations of hydrogen fluoride and a solidfluorides in ambient air led to the accumulation offluoride ion in the soil. The iodine entering with drinking water and food, was established to provide only 37.5-50% of the daily requirement of iodine. Increased fluoride ion content in urine and milk teeth in children is associated with the concentrations of the fluorine-containing pollutants in the ambient air and soil. The fluoride pollution against the background of the natural iodine deficiency was established to increase the frequency of functional and morphological disorders of the thyroid gland in children.

  9. Thyroid hormones association with depression severity and clinical outcome in patients with major depressive disorder.

    Science.gov (United States)

    Berent, Dominika; Zboralski, Krzysztof; Orzechowska, Agata; Gałecki, Piotr

    2014-01-01

    The clinical implications of thyroid hormones in depression have been studied extensively and still remains disputable. Supplementation of thyroid hormones is considered to augment and accelerate antidepressant treatment. Studies on the role of thyroid hormones in depression deliver contradictory results. Here we assess theirs impact on depression severity and final clinical outcome in patients with major depression. Thyrotropin, free thyroxine (FT4), and free triiodothyronine (FT3) concentrations were measured with automated quantitative enzyme immunoassay. Depression severity and final clinical outcome were rated with 17-itemic Hamilton Rating Scale for Depression [HDRS(17)] and Clinical Global Impression Scales for severity and for improvement (CGIs, CGIi). FT3 and FT4 concentrations were significantly positively correlated with clinical improvement evaluated with CGIi (R = 0.38, P = 0.012; R = 0.33, P = 0.034, respectively). There was a significant correlation between FT4 concentrations and depression severity assessed in HDRS(17) (R = 0.31, P = 0.047). Male patients presented significantly higher FT3 serum levels (Z = 2.34, P = 0.018) and significantly greater clinical improvement (Z = 2.36, P = 0.018) when compared to female patients. We conclude that free thyroid hormones concentrations are associated with depression severity and have an impact on final clinical outcome. It can be more efficient to augment and accelerate the treatment of major depressive disorder with triiodothyronine instead of levothyroxine because of individual differences in thyroid hormones metabolism.

  10. Growth hormone receptor deficiency (Laron syndrome) in black ...

    African Journals Online (AJOL)

    Non-Caucasians with growth honnone receptor (GHR) deficiency/Lamn syndrome among the .... 4,3 cm (-2,4 SOS for bone age 8,5 years at age 12); the girl's height at age 7 years was 77,5 cm (-8,0 SOS, height ... of serum incubated with '25I-labelled human growth hormone and expressed as relative specific binding ...

  11. Low intelligence but not attention deficit hyperactivity disorder is associated with resistance to thyroid hormone caused by mutation R316H in the thyroid hormone receptor {beta} gene

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, R.E.; Stein, M.A.; Chyna, B.; Phillips, W.; O`Brien, T.; Gutermuth, L.; Refetoff, S. [Univ. of Chicago, IL (United States); Duck, S.C. [Northwestern Univ. Medical School/Evanston Hospital, Evanston, IL (United States)

    1994-06-01

    Resistance to thyroid hormone (RTH) is a syndrome of reduced responsiveness of tissues to thyroid hormone. The clinical manifestations are variable and 46-50% of children with RTH have attention deficit hyperactivity disorder (ADD). The authors present a new family with RTH (F120) found to have a mutation R316H in the thyroid hormone receptor {beta} (TR{beta}) gene identical for that reported in an unrelated family. Assignment of the mutant allele and haplotyping based on CA repeat polymorphism were done on 16 family members. Semistructured diagnostic interviews and psychometric testing were used to determine the psychiatric diagnosis of 12 family members by examiners blinded to the genotype. Three subjects were identified to have the R316H allele as well as mildly elevated free T{sub 4} index (168 {+-} 12; normal range 77-135) and nonsuppressed TSH (4.1 {+-} 1.7 mU/L). Only 2 of the subjects with RTH were found to have ADD, while one family member homozygous for the wild type TR{beta} and normal thyroid function tests also had ADD. Unaffected family members had higher full scale intelligence quotients ({vert_bar}Q) (93 {+-} 7) than any of the 3 family members with RTH (77 {+-} 5, p = 0.006). These data do not support the genetic linkage of ADD and RTH, but do suggest that RTH is associated with lower IQ scores that may confer a high likelihood of exhibiting ADD symptoms. 20 refs., 2 figs., 2 tabs.

  12. Moderate weight loss is sufficient to affect thyroid hormone homeostasis and inhibit its peripheral conversion.

    Science.gov (United States)

    Agnihothri, Ritesh V; Courville, Amber B; Linderman, Joyce D; Smith, Sheila; Brychta, Robert; Remaley, Alan; Chen, Kong Y; Simchowitz, Louis; Celi, Francesco S

    2014-01-01

    Thyroid hormones are important determinants of energy expenditure, and in rodents, adipose tissue affects thyroid hormone homeostasis via leptin signaling. The relationship between thyroid hormones and nutritional status in humans has been assessed primarily in drastic dietary or bariatric surgery interventions, while limited information is available on serial assessment of this axis during moderate, prolonged dietary restriction. To evaluate the effects of moderate dietary restriction on thyroid hormone homeostasis, 47 subjects with a body mass index (BMI) of 25-45 kg/m(2) were enrolled in a longitudinal intervention study; 30 nonoverweight volunteers were also enrolled as controls. Overweight and obese subjects underwent a 12-month individualized dietary intervention aimed at achieving a 5-10% weight loss. The intervention resulted in a 6.3±0.9 kg (6.5±1.0%) weight loss. At baseline, thyrotropin (TSH) and T3 concentrations correlated significantly with fat mass (R=0.257, p=0.024 and R=0.318, p=0.005, respectively). After weight loss, T3 decreased significantly (from 112.7±3.1 to 101.8±2.6 ng/dL, p5% body weight. T3 concentration closely correlates with individual nutritional status, and moderate weight loss results in a decrease in T3 with minimal changes in other thyroid hormone homeostasis parameters. The data suggest that a decrease in peripheral conversion of the prohormone T4 into its hormonally active metabolite T3 is at least in part responsible for the observed changes in thyroid hormone homeostasis.

  13. Impact of Ecologically Unfriendly Environment on the Formation of Thyroid Pathology in Children Against Iodine Deficiency

    Directory of Open Access Journals (Sweden)

    N.S. Kosmynina

    2014-02-01

    Full Text Available By prevalence among thyroid pathological conditions in Ukraine, the diffuse nontoxic goiter is dominated, the frequency of which, in addition to iodine deficiency, is influenced by anthropogenic pollution of environment. The article evaluated the role of the negative impact of polluted environment on the formation of thyroid disease in children from ecologically unfriendly region on the background of endemic iodine deficiency compared with children from ecologically friendly area of iodine deficiency. It has been determined the frequency of diffuse endemic goiter in children from studied groups according to palpation and ultrasonography. The functional state of the pituitary-thyroid system in children living in iodine deficiency environmentally unfriendly and ecologically friendly areas has been researched.

  14. Diagnosis of growth hormone deficiency after pituitary surgery : the combined acipimox/GH-releasing hormone test

    NARCIS (Netherlands)

    Dieguez, C; Cordido, F; de Vries, WR; Veldhuyzen, BFE; van Thiel, E; Casanueva, FF; Koppeschaar, HPF

    OBJECTIVE Reduction of plasma free fatty acids leads to enhanced GH response after stimulation by GH-releasing hormone (GHRH). We studied the clinical usefulness of combined administration of acipimox and GHRH for the diagnosis of GH deficiency. DESIGN We evaluated 35 patients [mean age 53.0 years;

  15. Growth hormone treatment during pregnancy in a growth hormone-deficient woman

    DEFF Research Database (Denmark)

    Müller, J; Starup, J; Christiansen, J S

    1995-01-01

    protein 3 (IGFBP-3) during pregnancy, as well as birth weight and hormone levels after delivery in a 25-year-old woman with idiopathic, isolated GH deficiency diagnosed at the age of 7 years. As part of a clinical trial, the patient was treated with 2 IU/M2 GH for a period of 5 years. At this time she...

  16. Continuation of growth hormone therapy versus placebo in transition-phase patients with growth hormone deficiency

    DEFF Research Database (Denmark)

    Jørgensen, Jens; Nørrelund, Helene; Vahl, Nina

    2002-01-01

    In a placebo-controlled, parallel study of 18 patients with a mean age of 20 years who had confirmed growth hormone (GH) deficiency, we evaluated body composition, insulin sensitivity, and glucose turnover at baseline (when all were receiving GH replacement); after 12 months of continued GH therapy...

  17. Transcriptomic and phenotypic profiling in developing zebrafish exposed to thyroid hormone receptor agonists

    Energy Technology Data Exchange (ETDEWEB)

    Haggard, Derik E.; Noyes, Pamela D.; Waters, Katrina M.; Tanguay, Robert L.

    2018-04-01

    There is a need to develop novel, high-throughput screening and prioritization methods to identify chemicals with adverse estrogen, androgen, and thyroid activity to protect human health and the environment and is of interest to the Endocrine Disruptor Screening Program. The current aim is to explore the utility of zebrafish as a testing paradigm to classify endocrine activity using phenotypically anchored transcriptome profiling. Transcriptome analysis was conducted on embryos exposed to 25 estrogen-, androgen-, or thyroid-active chemicals at a concentration that elicited adverse malformations or mortality at 120 hours post-fertilization in 80% of the animals exposed. Analysis of the top 1000 significant differentially expressed transcripts across all treatments identified a unique transcriptional and phenotypic profile for thyroid hormone receptor agonists, which can be used as a biomarker screen for potential thyroid hormone agonists.

  18. Changes in rodent thyroid hormones and cyclic-AMP following treatment with pineal indolic compounds.

    Science.gov (United States)

    Nir, I; Hirschmann, N; Puder, M; Petrank, J

    1978-05-01

    Treatment of rats with pineal indolic compounds 5-methoxytryptophol, 5-hydroxytryptophol and serotonin brought about a significant increase in serum thyroxine levels, while serotonin and melatonin caused an increase in thyroid cAMP content with corresponding decrease in the gland's hormones. The total quantity of cAMP in the thyroid was also increased by melatonin in the organ culture system. All these findings would indicate that some of the pineal indoleamines elicit a direct action on the thyroid by stimulating the adenyl cyclase activity and intrathyroidal cAMP, bringing about increased release of thyroxine into the blood stream, and that this is usually not accompanied by adequate synthesis in the gland. Our observation that continuous darkness, which stimulates pineal activity, also brought about an increase in cAMP, concours with our finding of a stimulatory effect of the indolic compounds on thyroid hormone release.

  19. Temperature induced variation in gene expression of thyroid hormone receptors and deiodinases of European eel (Anguilla anguilla) larvae

    DEFF Research Database (Denmark)

    Politis, Sebastian Nikitas; Servili, A.; Mazurais, D.

    2018-01-01

    Thyroid hormones (THs) are key regulators of growth, development, and metabolism in vertebrates and influence early life development of fish. TH is produced in the thyroid gland (or thyroid follicles) mainly as T4 (thyroxine), which is metabolized to T3 (3,5,3'-triiodothyronine) and T2 (3,5-diiod...

  20. Disorders of the equine thyroid gland.

    Science.gov (United States)

    Breuhaus, Babetta A

    2011-04-01

    Regulatory control of the thyroid gland in horses is similar to other species. Clinical signs of hypothyroidism in adult horses are minimal. Several drugs and physiologic and pathophysiological states can cause circulating thyroid hormone concentrations to be low without actual pathology of the thyroid gland. Thus, nonthyroidal factors must be ruled out before a diagnosis of hypothyroidism can be made. Thyroid hormone supplementation seems to be well tolerated, even in euthyroid horses. Neonatal foals have very high circulating thyroid hormone concentrations, and deficiencies result in significant clinical signs. Unlike in adults, two syndromes of hypothyroidism are well described in foals. Copyright © 2011. Published by Elsevier Inc.

  1. Growth hormone treatment during pregnancy in a growth hormone-deficient woman

    DEFF Research Database (Denmark)

    Müller, J; Starup, J; Christiansen, J S

    1995-01-01

    Information on the course and outcome of pregnancies in growth hormone (GH)-deficient patients is sparse, and GH treatment during pregnancy in such women has not been described previously. We have studied fetal growth and serum levels of GH, insulin-like growth factor I (IGF-I) and IGF binding...... protein 3 (IGFBP-3) during pregnancy, as well as birth weight and hormone levels after delivery in a 25-year-old woman with idiopathic, isolated GH deficiency diagnosed at the age of 7 years. As part of a clinical trial, the patient was treated with 2 IU/M2 GH for a period of 5 years. At this time she...... became pregnant after donor insemination. The GH treatment was continued until variant GH production from the placenta was evident. Serum levels of GH, IGF-I and IGFBP-3 were measured monthly during pregnancy after 3 days off GH therapy. Abdominal ultrasound was performed five times. Hormonal levels were...

  2. 'Apathetic' thyrotoxicosis presenting with hypercalcaemia and spurious normalization of serum thyroid hormone levels.

    OpenAIRE

    Ralston, S. H.; Fraser, W. D.; Soukop, M.; McKillop, J. H.

    1987-01-01

    A patient with thyrotoxicosis presented with weight loss and hypercalcaemia, leading to an erroneous diagnosis of occult malignant disease. Intercurrent illness and drug treatment of hypercalcaemia in this patient caused a depression of circulating thyroid hormone levels, leading to a delay in diagnosis. Radionuclide studies of thyroid function, in contrast, consistently suggested a thyrotoxic state. It is suggested that in this situation, radionuclide studies may give a more accurate assessm...

  3. Characterization of tissue metabolism of thyroid hormones in very premature infants

    International Nuclear Information System (INIS)

    Pavelka, S.; Kopecky, J.; Brauner, P.

    1998-01-01

    Thyroid status was characterized in very preterm infants (gestational age 23-32 wk; n = 61) from birth through day 14; in those infants who died within 16 days of delivery (n = 10) it was also correlated with the metabolism of thyroid hormones in peripheral tissues (brain, liver, kidney, skeletal muscle, and different localities of adipose tissue). The results obtained support the view that peripheral tissues of very premature infants are involved in local generation of triiodothyronine (T 3 ) and inactivation of thyroid hormones, but do not represent a major source of circulating T 3 . In this study observations on postnatal development of plasma thyroid hormone levels in normal and critically ill premature neonates are presented. Enzyme activities of all three types of iodothyronine deiodinases were followed in autopsy samples from brain, liver, kidney, muscle, and adipose tissue depots, to better characterize the relationships between peripheral metabolism of thyroid hormones and thyroid status in critically ill very preterm newborns. Plasma concentrations of total T 3 , total T 4 , and total rT 3 were estimated by competitive radioimmunoassay. Plasma TSH concentrations were measured by microparticle enzyme immunoassay. Measurable activities of deiodinases of type I, II and II were detected post mortem in all tissue samples, except for type II activity in kidney. No correlation between postnatal age and the enzyme activities was found in in different tissues in the group of infants who died by 16 days of age. All activities were the highest in liver and differed significantly in particular tissues. Obtained results suggest tat, in contrast to adults, iodothyronine metabolism in peripheral tissues of premature newborns seems to be dominated by thyroid hormones inactivation, and T 3 production mainly for local use inside tissues. (authors)

  4. Syndrome of Reduced Sensitivity to Thyroid Hormones: Two Case Reports and a Literature Review

    Directory of Open Access Journals (Sweden)

    Anastasios Anyfantakis

    2016-01-01

    Full Text Available Resistance to thyroid hormone (RTH is an extremely rare dominantly inherited condition of impaired tissue responsiveness to thyroid hormone (TH. Most patients with RTH have mutations in the gene that encodes the β isoform of the receptor of thyroid hormone (THR-β gene. Mutant receptors are unable to activate or repress target genes. The majority of them are asymptomatic or rarely have hypo- or hyperthyroidism. RTH is suspected by the finding of persistent elevation of serum levels of free T3 (FT3 and free T4 (FT4 and nonsuppressed TSH. We present two cases of RTH diagnosed after total thyroidectomy. The first patient was initially diagnosed with primary hyperthyroidism due to toxic multinodular goiter. The second patient had undergone thyroidectomy for multinodular goiter 16 years before diagnosis of RTH. After thyroidectomy, although on relatively high doses of levothyroxine, both of them presented with the laboratory findings of RTH. Genetic analysis revealed RTH.

  5. Establishment of reference range for thyroid hormones in normal pregnant women in China's coastal area.

    Science.gov (United States)

    Zha, J; Ming, D; Jiang, Y; Huang, C; Jiang, T; Chen, C; Lin, R; Su, W; Gu, S

    2014-01-01

    The current study aims to establish reference ranges for thyroid hormones in normal pregnant women during their pregnancy period. A one-time cross-sectional survey was conducted on 490 normal pregnant women and 51 nonpregnant women (control). The serum thyroid stimulating hormone (TSH), free triiodothyronine (FT3), and free tetraiodothyronine (FT4) levels were measured. The serum FT3 and FT4 levels in pregnant women decreased gradually from the first to the last three months of pregnancy (p serum TSH level increased gradually during the whole pregnancy (p < 0.01), and was significantly lower than the control (p < 0.01) in the first three months. However, in the middle and last three months of pregnancy, TSH was higher than the control (p < 0.01). The thyroid hormone levels in normal pregnant women are different from those in non-pregnant women; significant differences exist among the three stages of pregnancy.

  6. Intrauterine Zn Deficiency Favors Thyrotropin-Releasing Hormone-Increasing Effects on Thyrotropin Serum Levels and Induces Subclinical Hypothyroidism in Weaned Rats

    Directory of Open Access Journals (Sweden)

    Viridiana Alcántara-Alonso

    2017-10-01

    Full Text Available Individuals who consume a diet deficient in zinc (Zn-deficient develop alterations in hypothalamic-pituitary-thyroid axis function, i.e., a low metabolic rate and cold insensitivity. Although those disturbances are related to primary hypothyroidism, intrauterine or postnatal Zn-deficient adults have an increased thyrotropin (TSH concentration, but unchanged thyroid hormone (TH levels and decreased body weight. This does not support the view that the hypothyroidism develops due to a low Zn intake. In addition, intrauterine or postnatal Zn-deficiency in weaned and adult rats reduces the activity of pyroglutamyl aminopeptidase II (PPII in the medial-basal hypothalamus (MBH. PPII is an enzyme that degrades thyrotropin-releasing hormone (TRH. This hypothalamic peptide stimulates its receptor in adenohypophysis, thereby increasing TSH release. We analyzed whether earlier low TH is responsible for the high TSH levels reported in adults, or if TRH release is enhanced by Zn deficiency at weaning. Dams were fed a 2 ppm Zn-deficient diet in the period from one week prior to gestation and up to three weeks after delivery. We found a high release of hypothalamic TRH, which along with reduced MBH PPII activity, increased TSH levels in Zn-deficient pups independently of changes in TH concentration. We found that primary hypothyroidism did not develop in intrauterine Zn-deficient weaned rats and we confirmed that metal deficiency enhances TSH levels since early-life, favoring subclinical hypothyroidism development which remains into adulthood.

  7. Thyroid hormone and adrenergic signaling interact to control pineal expression of the dopamine receptor D4 gene (Drd4)

    DEFF Research Database (Denmark)

    Kim, Jong-So; Bailey, Michael J; Weller, Joan L

    2009-01-01

    is circadian in nature and under photoneural control. Whereas most rhythmically expressed genes in the pineal are controlled by adrenergic/cAMP signaling, Drd4 expression also requires thyroid hormone. This advance raises the questions of whether Drd4 expression is regulated by this mechanism in other systems...... and whether thyroid hormone controls expression of other genes in the pineal gland....

  8. T-screen to quantify functional potentiating, antagonistic and thyroid hormone-like activities of poly halogenated aromatic hydrocarbons (PHAHs)

    NARCIS (Netherlands)

    Schriks, M.; Vrabie, C.M.; Gutleb, A.C.; Faassen, E.J.; Rietjens, I.M.C.M.; Murk, A.J.

    2006-01-01

    The present study investigates chemical thyroid hormone disruption at the level of thyroid hormone receptor (TR) functioning. To this end the (ant)agonistic action of a series of xenobiotics was tested in the newly developed T-screen. This assay makes use of a GH3 rat pituitary cell line, that

  9. Thyroid hormone signalling genes are regulated by photoperiod in the hypothalamus of F344 rats.

    Directory of Open Access Journals (Sweden)

    Alexander W Ross

    Full Text Available Seasonal animals adapt their physiology and behaviour in anticipation of climate change to optimise survival of their offspring. Intra-hypothalamic thyroid hormone signalling plays an important role in seasonal responses in mammals and birds. In the F344 rat, photoperiod stimulates profound changes in food intake, body weight and reproductive status. Previous investigations of the F344 rat have suggested a role for thyroid hormone metabolism, but have only considered Dio2 expression, which was elevated in long day photoperiods. Microarray analysis was used to identify time-dependent changes in photoperiod responsive genes, which may underlie the photoperiod-dependent phenotypes of the juvenile F344 rat. The most significant changes are those related to thyroid hormone metabolism and transport. Using photoperiod manipulations and melatonin injections into long day photoperiod (LD rats to mimic short day (SD, we show photoinduction and photosuppression gene expression profiles and melatonin responsiveness of genes by in situ hybridization; TSHβ, CGA, Dio2 and Oatp1c1 genes were all elevated in LD whilst in SD, Dio3 and MCT-8 mRNA were increased. NPY was elevated in SD whilst GALP increased in LD. The photoinduction and photosuppression profiles for GALP were compared to that of GHRH with GALP expression following GHRH temporally. We also reveal gene sets involved in photoperiodic responses, including retinoic acid and Wnt/ß-catenin signalling. This study extends our knowledge of hypothalamic regulation by photoperiod, by revealing large temporal changes in expression of thyroid hormone signalling genes following photoperiod switch. Surprisingly, large changes in hypothalamic thyroid hormone levels or TRH expression were not detected. Expression of NPY and GALP, two genes known to regulate GHRH, were also changed by photoperiod. Whether these genes could provide links between thyroid hormone signalling and the regulation of the growth axis

  10. The bactericidal agent triclosan modulates thyroid hormone-associated gene expression and disrupts postembryonic anuran development

    Energy Technology Data Exchange (ETDEWEB)

    Veldhoen, Nik [Department of Biochemistry and Microbiology, P.O. Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia V8W 3P6 (Canada); Skirrow, Rachel C. [Pacific Environmental Science Centre, 2645 Dollarton Highway, North Vancouver, British Columbia V7H 1V2 (Canada); Osachoff, Heather [Pacific Environmental Science Centre, 2645 Dollarton Highway, North Vancouver, British Columbia V7H 1V2 (Canada); Wigmore, Heidi [Pacific Environmental Science Centre, 2645 Dollarton Highway, North Vancouver, British Columbia V7H 1V2 (Canada); Clapson, David J. [Department of Biochemistry and Microbiology, P.O. Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia V8W 3P6 (Canada); Gunderson, Mark P. [Department of Biochemistry and Microbiology, P.O. Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia V8W 3P6 (Canada); Van Aggelen, Graham [Pacific Environmental Science Centre, 2645 Dollarton Highway, North Vancouver, British Columbia V7H 1V2 (Canada); Helbing, Caren C. [Department of Biochemistry and Microbiology, P.O. Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia V8W 3P6 (Canada)]. E-mail: chelbing@uvic.ca

    2006-12-01

    We investigated whether exposure to environmentally relevant concentrations of the bactericidal agent, triclosan, induces changes in the thyroid hormone-mediated process of metamorphosis of the North American bullfrog, Rana catesbeiana and alters the expression profile of thyroid hormone receptor (TR) {alpha} and {beta}, basic transcription element binding protein (BTEB) and proliferating nuclear cell antigen (PCNA) gene transcripts. Premetamorphic tadpoles were immersed in environmentally relevant concentrations of triclosan and injected with 1 x 10{sup -11} mol/g body weight 3,5,3'-triiodothyronine (T{sub 3}) or vehicle control. Morphometric measurements and steady-state mRNA levels obtained by quantitative polymerase chain reaction were determined. mRNA abundance was also examined in Xenopus laevis XTC-2 cells treated with triclosan and/or 10 nM T{sub 3}. Tadpoles pretreated with triclosan concentrations as low as 0.15 {+-} 0.03 {mu}g/L for 4 days showed increased hindlimb development and a decrease in total body weight following T{sub 3} administration. Triclosan exposure also resulted in decreased T{sub 3}-mediated TR{beta} mRNA expression in the tadpole tail fin and increased levels of PCNA transcript in the brain within 48 h of T{sub 3} treatment whereas TR{alpha} and BTEB were unaffected. Triclosan alone altered thyroid hormone receptor {alpha} transcript levels in the brain of premetamorphic tadpoles and induced a transient weight loss. In XTC-2 cells, exposure to T{sub 3} plus nominal concentrations of triclosan as low as 0.03 {mu}g/L for 24 h resulted in altered thyroid hormone receptor mRNA expression. Exposure to low levels of triclosan disrupts thyroid hormone-associated gene expression and can alter the rate of thyroid hormone-mediated postembryonic anuran development.

  11. The bactericidal agent triclosan modulates thyroid hormone-associated gene expression and disrupts postembryonic anuran development

    International Nuclear Information System (INIS)

    Veldhoen, Nik; Skirrow, Rachel C.; Osachoff, Heather; Wigmore, Heidi; Clapson, David J.; Gunderson, Mark P.; Van Aggelen, Graham; Helbing, Caren C.

    2006-01-01

    We investigated whether exposure to environmentally relevant concentrations of the bactericidal agent, triclosan, induces changes in the thyroid hormone-mediated process of metamorphosis of the North American bullfrog, Rana catesbeiana and alters the expression profile of thyroid hormone receptor (TR) α and β, basic transcription element binding protein (BTEB) and proliferating nuclear cell antigen (PCNA) gene transcripts. Premetamorphic tadpoles were immersed in environmentally relevant concentrations of triclosan and injected with 1 x 10 -11 mol/g body weight 3,5,3'-triiodothyronine (T 3 ) or vehicle control. Morphometric measurements and steady-state mRNA levels obtained by quantitative polymerase chain reaction were determined. mRNA abundance was also examined in Xenopus laevis XTC-2 cells treated with triclosan and/or 10 nM T 3 . Tadpoles pretreated with triclosan concentrations as low as 0.15 ± 0.03 μg/L for 4 days showed increased hindlimb development and a decrease in total body weight following T 3 administration. Triclosan exposure also resulted in decreased T 3 -mediated TRβ mRNA expression in the tadpole tail fin and increased levels of PCNA transcript in the brain within 48 h of T 3 treatment whereas TRα and BTEB were unaffected. Triclosan alone altered thyroid hormone receptor α transcript levels in the brain of premetamorphic tadpoles and induced a transient weight loss. In XTC-2 cells, exposure to T 3 plus nominal concentrations of triclosan as low as 0.03 μg/L for 24 h resulted in altered thyroid hormone receptor mRNA expression. Exposure to low levels of triclosan disrupts thyroid hormone-associated gene expression and can alter the rate of thyroid hormone-mediated postembryonic anuran development

  12. Identification of a novel modulator of thyroid hormone receptor-mediated action.

    Directory of Open Access Journals (Sweden)

    Bernhard G Baumgartner

    Full Text Available BACKGROUND: Diabetes is characterized by reduced thyroid function and altered myogenesis after muscle injury. Here we identify a novel component of thyroid hormone action that is repressed in diabetic rat muscle. METHODOLOGY/PRINCIPAL FINDINGS: We have identified a gene, named DOR, abundantly expressed in insulin-sensitive tissues such as skeletal muscle and heart, whose expression is highly repressed in muscle from obese diabetic rats. DOR expression is up-regulated during muscle differentiation and its loss-of-function has a negative impact on gene expression programmes linked to myogenesis or driven by thyroid hormones. In agreement with this, DOR enhances the transcriptional activity of the thyroid hormone receptor TR(alpha1. This function is driven by the N-terminal part of the protein. Moreover, DOR physically interacts with TR( alpha1 and to T(3-responsive promoters, as shown by ChIP assays. T(3 stimulation also promotes the mobilization of DOR from its localization in nuclear PML bodies, thereby indicating that its nuclear localization and cellular function may be related. CONCLUSIONS/SIGNIFICANCE: Our data indicate that DOR modulates thyroid hormone function and controls myogenesis. DOR expression is down-regulated in skeletal muscle in diabetes. This finding may be of relevance for the alterations in muscle function associated with this disease.

  13. Identification of a Novel Modulator of Thyroid Hormone Receptor-Mediated Action

    Science.gov (United States)

    Ribas, Vicent; Burghardt, Hans E.; Bach, Daniel; Villar, Ana Victoria; Paz, José C.; González, Meritxell; Camps, Marta; Oriola, Josep; Rivera, Francisca; Palacín, Manuel; Zorzano, Antonio

    2007-01-01

    Background Diabetes is characterized by reduced thyroid function and altered myogenesis after muscle injury. Here we identify a novel component of thyroid hormone action that is repressed in diabetic rat muscle. Methodology/Principal Findings We have identified a gene, named DOR, abundantly expressed in insulin-sensitive tissues such as skeletal muscle and heart, whose expression is highly repressed in muscle from obese diabetic rats. DOR expression is up-regulated during muscle differentiation and its loss-of-function has a negative impact on gene expression programmes linked to myogenesis or driven by thyroid hormones. In agreement with this, DOR enhances the transcriptional activity of the thyroid hormone receptor TRα1. This function is driven by the N-terminal part of the protein. Moreover, DOR physically interacts with TR α1 and to T3-responsive promoters, as shown by ChIP assays. T3 stimulation also promotes the mobilization of DOR from its localization in nuclear PML bodies, thereby indicating that its nuclear localization and cellular function may be related. Conclusions/Significance Our data indicate that DOR modulates thyroid hormone function and controls myogenesis. DOR expression is down-regulated in skeletal muscle in diabetes. This finding may be of relevance for the alterations in muscle function associated with this disease. PMID:18030323

  14. Hypothyroxinemia Induced by Mild Iodine Deficiency Deregulats Thyroid Proteins during Gestation and Lactation in Dams

    Directory of Open Access Journals (Sweden)

    Jie Chen

    2013-08-01

    Full Text Available The main object of the present study was to explore the effect on thyroidal proteins following mild iodine deficiency (ID-induced maternal hypothyroxinemia during pregnancy and lactation. In the present study, we established a maternal hypothyroxinemia model in female Wistar rats by using a mild ID diet. Maternal thyroid iodine content and thyroid weight were measured. Expressions of thyroid-associated proteins were analyzed. The results showed that the mild ID diet increased thyroid weight, decreased thyroid iodine content and increased expressions of thyroid transcription factor 1, paired box gene 8 and Na+/I− symporter on gestational day (GD 19 and postpartum days (PN 21 in the maternal thyroid. Moreover, the up-regulated expressions of type 1 iodothyronine deiodinase (DIO1 and type 2 iodothyronine deiodinase (DIO2 were detected in the mild ID group on GD19 and PN21. Taken together, our data indicates that during pregnancy and lactation, a maternal mild ID could induce hypothyroxinemia and increase the thyroidal DIO1 and DIO2 levels.

  15. Thyroid hormone induced oxygen consumption and glucose-uptake in human mononuclear cells

    DEFF Research Database (Denmark)

    Kvetny, J; Matzen, L E

    1989-01-01

    Cellular oxygen consumption and glucose metabolism were examined in human mononuclear blood cells. The cellular oxygen consumption and glucose uptake were dependent on the number of cells, the temperature and the duration of incubation. Stimulation of the cells by T4 and T3 led to a dose dependen...... thyroid hormones and insulin exerted an additive effect on glucose uptake. Our study indicates a direct intracellular effect of T4 independent of its conversion to T3 and a different mechanism for insulin dependent and thyroid hormone glucose uptake....

  16. (−) Arctigenin and (+) Pinoresinol Are Antagonists of the Human Thyroid Hormone Receptor β

    Science.gov (United States)

    2015-01-01

    Lignans are important biologically active dietary polyphenolic compounds. Consumption of foods that are rich in lignans is associated with positive health effects. Using modeling tools to probe the ligand-binding pockets of molecular receptors, we found that lignans have high docking affinity for the human thyroid hormone receptor β. Follow-up experimental results show that lignans (−) arctigenin and (+) pinoresinol are antagonists of the human thyroid hormone receptor β. The modeled complexes show key plausible interactions between the two ligands and important amino acid residues of the receptor. PMID:25383984

  17. Negative Feedback Control of Pituitary Thyroid-stimulating Hormone Synthesis and Secretion by Thyroid Hormones during Metamorphosis in Xenopus laevis

    Science.gov (United States)

    A basic understanding of the endocrinology of the hypothalamic-pituitary-thyroid (HPT) axis of anuran larvae is necessary for predicting the consequences of HPT perturbation by thyroid-disrupting chemicals (TDCs) on the whole organism. This project examined negative feedback con...

  18. Effect of race, gender and age on thyroid and thyroid stimulating hormone levels in north west frontier province, Pakistan

    International Nuclear Information System (INIS)

    Ahmed, Z.; Khan, M.A.; Haq, A.U.

    2009-01-01

    Thyroid is one of the ductless endocrine gland, which is located immediately below the larynx on either side of and anterior to the trachea. The principal hormones of thyroid gland are thyroxine (T4) and triiodothyronine (T3). The current study was carried out to investigate the impact of race, gender and area on the levels of Thyroxine (T4), Triiodothyronine (T3) and Thyroid Stimulating Hormone (TSH) in normal healthy individuals. Methods: Serum levels of T4, T3 and TSH in 498 normal healthy individuals belonging to different districts of North West Frontier Province, Pakistan, were examined. Serum T4 and T3 were analysed by Radio Immuno Assay (RIA) method whereas TSH was estimated by Immunoradiometric assay (IRMA) method. Results: Levels of T4, T3 and TSH ranged from 53 to 167 m mu mol/L and 0.3-4.8 mu mol/L respectively. The levels of these hormones show significant change from the reference values that are used in clinical laboratories as well as in Institute of Rauclear Medicine (IRNUM), Peshawar, Pakistan. Conclusion: It is concluded that the age, gender, race and area, all have an appreciable effect on the levels T4, T3 and TSH. (author)

  19. Thyroid hormones and menstrual cycle function in a longitudinal cohort of premenopausal women.

    Science.gov (United States)

    Jacobson, Melanie H; Howards, Penelope P; Darrow, Lyndsey A; Meadows, Juliana W; Kesner, James S; Spencer, Jessica B; Terrell, Metrecia L; Marcus, Michele

    2018-03-08

    Previous studies have reported that hyperthyroid and hypothyroid women experience menstrual irregularities more often compared with euthyroid women, but reasons for this are not well-understood and studies on thyroid hormones among euthyroid women are lacking. In a prospective cohort study of euthyroid women, this study characterised the relationship between thyroid hormone concentrations and prospectively collected menstrual function outcomes. Between 2004-2014, 86 euthyroid premenopausal women not lactating or taking hormonal medications participated in a study measuring menstrual function. Serum thyroid hormones were measured before the menstrual function study began. Women then collected first morning urine voids and completed daily bleeding diaries every day for three cycles. Urinary oestrogen and progesterone metabolites (estrone 3-glucuronide (E 1 3G) and pregnanediol 3-glucuronide (Pd3G)) and follicle-stimulating hormone were measured and adjusted for creatinine (Cr). Total thyroxine (T 4 ) concentrations were positively associated with Pd3G and E 1 3G. Women with higher (vs lower) T 4 had greater luteal phase maximum Pd3G (Pd3G = 11.7 μg/mg Cr for women with high T 4 vs Pd3G = 9.5 and 8.1 μg/mg Cr for women with medium and low T 4 , respectively) and greater follicular phase maximum E 1 3G (E 1 3G = 41.7 ng/mg Cr for women with high T 4 vs E 1 3G = 34.3 and 33.7 ng/mg Cr for women with medium and low T 4 , respectively). Circulating thyroid hormone concentrations were associated with subtle differences in menstrual cycle function outcomes, particularly sex steroid hormone levels in healthy women. Results contribute to the understanding of the relationship between thyroid function and the menstrual cycle, and may have implications for fertility and chronic disease. © 2018 John Wiley & Sons Ltd.

  20. The Influence of Thyroid Hormones on Leptin and Resistin Levels in Hyperthyroid Female Patients

    Directory of Open Access Journals (Sweden)

    Al-Hindawi Sahar H

    2018-01-01

    Full Text Available Background: Hyperthyroidism or thyrotoxicosis occurs due to excess release of thyroid hormone. These hormones regulate the body’s energy balance and have effects on adipokine level. There are several reports suggesting interrelation between adipokines (resistin and leptin with thyroid dysfunction. Objectives: This study was established to investigate the effect of thyroid hormones in hyperthyroidism state on the level of some adipokines, leptin and resistin; in comparison with control. Patients and Methods: The present study included 50 Iraqi female patients with hyperthyroidism with age ranged between 30-58 years and 30 healthy controls with age ranged between 30-53 years. Serum samples were collected from study groups. The levels of thyroid hormones (TSH, T4 and T3 were determined by using automated Chemiluminescence Immunoassay (CLIA analysis system. Detection of leptin hormone and resistin hormone levels in the serum were determined by an enzyme linked immunosorbent assay (ELISA kits. Results: The results revealed that serum leptin levels were significantly low (P<0.004 in hyperthyroid patient groups as compared to control, and there were significant negative correlations between T4 and leptin (P<0.0001; also, T3 and leptin (P<0.05. Resistin hormone level increased non-significantly (P˃0.05 than control level; and there was significant negative correlation between TSH and resistin (P<0.035. Conclusion: The study shows that there is complex interrelation between adipocytokines (leptin and resistin with thyroid gland and pituitary gland. Leptin levels were decreased in hyperthyroid patients than control and associated negatively with T4 and T3 levels, while resistin levels were increased non-significantly than control and associated negatively with TSH level. They affect each other in their physiological function in the human body.

  1. Epigenetic regulation of thyroid hormone receptor beta in renal cancer.

    Directory of Open Access Journals (Sweden)

    Anna Wojcicka

    Full Text Available Thyroid hormone receptor beta (THRB gene is commonly deregulated in cancers and, as strengthened by animal models, postulated to play a tumor-suppressive role. Our previous studies revealed downregulation of THRB in clear cell renal cell carcinoma (ccRCC, but the culpable mechanisms have not been fully elucidated. Since epigenetic regulation is a common mechanism influencing the expression of tumor suppressors, we hypothesized that downregulation of THRB in renal cancer results from epigenetic aberrances, including CpG methylation and microRNA-dependent silencing. Our study revealed that ccRCC tumors exhibited a 56% decrease in THRB and a 37% increase in DNA methyltransferase 1 (DNMT1 expression when compared with paired non-neoplastic control samples. However, THRB CpG methylation analysis performed using BSP, SNaPshot and MSP-PCR consistently revealed no changes in methylation patterns between matched tumor and control samples. In silico analysis resulted in identification of four microRNAs (miR-155, miR-425, miR-592, and miR-599 as potentially targeting THRB transcript. Luciferase assay showed direct binding of miR-155 and miR-425 to 3'UTR of THRB, and subsequent in vivo analyses revealed that transfection of UOK171 cell line with synthetic miR-155 or miR-425 resulted in decreased expression of endogenous TRHB by 22% and 64%, respectively. Finally, real-time PCR analysis showed significant upregulation of miR-155 (354% and miR-425 (162% in ccRCC when compared with matched controls. Moreover, microRNA levels were negatively correlated with the amount of THRB transcript in tissue samples. We conclude that CpG methylation is not the major mechanism contributing to decreased THRB expression in ccRCC. In contrast, THRB is targeted by microRNAs miR-155 and miR-425, whose increased expression may be responsible for downregulation of THRB in ccRCC tumors.

  2. Dietary Iodine Affected the GSH-Px to Regulate the Thyroid Hormones in Thyroid Gland of Rex Rabbits.

    Science.gov (United States)

    Qin, Feng; Pan, Xiaoqing; Yang, Jie; Li, Sheng; Shao, Le; Zhang, Xia; Liu, Beiyi; Li, Jian

    2018-02-01

    Iodine (I) is an essential trace element that can influence animal health and productivity. In this study, we investigated the effects of dietary iodine on the antioxidant indices of organ (liver and thyroid gland) and messenger RNA (mRNA) expression of glutathione peroxidase (GSH-Px) in Rex rabbits. A total of 120 4-month-old Rex rabbits (2235.4 ± 13.04 g BW) were divided into four equal groups, and their diets were supplemented with iodine (0, 0.2, 2, or 4 mg/kg dry matter (DM)). The iodine concentration in basal diet (control group) was 0.36 mg/kg DM. In most of measured parameters, supplemental iodine exerted no significant effect. Growth and slaughter performance and organ weight were not influenced significantly by iodine supplementation. Serum T 3 was significantly lower in 2-mg I group than in 0.2 and 4-mg I groups (P  0.05). Conversely, serum catalase (CAT) was significantly reduced (P thyroid, GSH-Px was higher in the 2-mg I group than in the 0.2- and 4-mg I groups (P  0.05). In the thyroid gland, the mRNA expression level of GSH-Px was higher in the 2-mg I group than in the 4-mg I group (P thyroid gland. Thus, on the basis of serum T 3 and GSH-Px levels in the thyroid gland, we hypothesized that GSH-Px secretion was increased by adding dietary iodine in the thyroid, which may inhibit the H 2 O 2 generation and further influence the thyroid hormone synthesis.

  3. Using Hashimoto thyroiditis as gold standard to determine the upper limit value of thyroid stimulating hormone in a Chinese cohort.

    Science.gov (United States)

    Li, Yu; Chen, Dong-Ning; Cui, Jing; Xin, Zhong; Yang, Guang-Ran; Niu, Ming-Jia; Yang, Jin-Kui

    2016-11-06

    Subclinical hypothyroidism, commonly caused by Hashimoto thyroiditis (HT), is a risk factor for cardiovascular diseases. This disorder is defined as merely having elevated serum thyroid stimulating hormone (TSH) levels. However, the upper limit of reference range for TSH is debated recently. This study was to determine the cutoff value for the upper normal limit of TSH in a cohort using the prevalence of Hashimoto thyroiditis as "gold" calibration standard. The research population was medical staff of 2856 individuals who took part in health examination annually. Serum free triiodothyronine (FT3), free thyroxine (FT4), TSH, thyroid peroxidase antibody (TPAb), thyroglobulin antibody (TGAb) and other biochemistry parameters were tested. Meanwhile, thyroid ultrasound examination was performed. The diagnosis of HT was based on presence of thyroid antibodies (TPAb and TGAb) and abnormalities of thyroid ultrasound examination. We used two different methods to estimate the cutoff point of TSH based on the prevalence of HT. Joinpoint regression showed the prevalence of HT increased significantly at the ninth decile of TSH value corresponding to 2.9 mU/L. ROC curve showed a TSH cutoff value of 2.6 mU/L with the maximized sensitivity and specificity in identifying HT. Using the newly defined cutoff value of TSH can detect patients with hyperlipidemia more efficiently, which may indicate our approach to define the upper limit of TSH can make more sense from the clinical point of view. A significant increase in the prevalence of HT occurred among individuals with a TSH of 2.6-2.9 mU/L made it possible to determine the cutoff value of normal upper limit of TSH.

  4. Clinical significance of endogenously labelled thyroid hormones in the diagnosis of thyroidal autonomy

    International Nuclear Information System (INIS)

    Waters, W.; Kutzim, H.

    1983-01-01

    The clinical value of the determination of 123 I concentration in serum 48 hrs after tracer administration ( 123 I) 48 is investigated with special regard to thyroidal autonomy. Serum radioiodine concentration, thyroid radioiodide uptake at 4 and at 48 hrs were measured in 74 healthy subjects and patients with simple goiter, in 36 patients with thyroidal autonomy (diagnosis by thyroid suppression test), and in 20 hyperthyroid patients. 83% of the patients with elevated radioiodine concentration belonged to the group of thyroidal autonomy. The product of radioiodine concentration and thyroid radioiodide uptake is a much better parameter. 95% of the patients in which this product was elevated, belonged to the autonomy group (5% diagnostic error). Also in the control group the diagnostic error was 5%. The combination of ( 123 I) 48 with the result of the TRH-test is very useful in excluding thyroidal autonomy, if ( 123 I) 48 is normal and the TRH-test is positive (100% of the patients have regulated thyroid glands.) 94% of the patients having elevated ( 123 I) 48 and a negative TRH-test belonged to the group of thyroidal autonomy. A very useful combination for the diagnosis of borderline hyperthyroidism is the determination of the product of ( 123 I) 48 and the uptake together with the pulse rate or fine tremor of the fingers (or TRH-test). The results suggest that the determination of ( 123 I) 48 is a very good parameter of thyroidal autonomy beside the thyroid suppression test. It may be used alone for the diagnosis of thyroidal autonomy if the suppression test is contraindicated. In the diagnosis of borderline hyperthyroidism its determination makes the suppression test unnecessary in many instances. (orig.) [de

  5. Thyroid hormone-like and estrogenic activity of hydroxylated PCBs in cell culture

    International Nuclear Information System (INIS)

    Kitamura, Shigeyuki; Jinno, Norimasa; Suzuki, Tomoharu; Sugihara, Kazumi; Ohta, Shigeru; Kuroki, Hiroaki; Fujimoto, Nariaki

    2005-01-01

    The thyroid hormone-disrupting activity of hydroxylated PCBs was examined. 4-Hydroxy-2,2',3,4',5,5'-hexachlorobiphenyl (4-OH-2,2',3,4',5,5'-HxCB), 4-hydroxy-3,3',4',5-tetrachlorobiphenyl (4-OH-3,3',4',5-TCB) and 4,4'-dihydroxy-3,3',5,5'-tetrachlorobiphenyl (4,4'-diOH-3,3',5,5'-TCB), which have been detected as metabolites of PCBs in animals and humans, and six other 4-hydroxylated PCBs markedly inhibited the binding of triiodothyronine (1 x 10 -10 M) to thyroid hormone receptor (TR) in the concentration range of 1 x 10 -6 to 1 x 10 -4 M. However, 4-hydroxy-2',4',6'-trichlorobiphenyl (4-OH-2',4',6'-TCB), 3-hydroxy-2,2',5,5'-tetrachlorobiphenyl, 4-hydroxy-2,2',5,5'-tetrachlorobiphenyl, 4-hydroxy-2,3,3',4'-tetrachlorobiphenyl, 2,3',5,5'-tetrachlorobiphenyl and 2,3',4',5,5'-pentachlorodiphenyl did not show affinity for TR. The thyroid hormonal activity of PCBs was also examined using rat pituitary cell line GH3 cells, which grow and release growth hormone in a thyroid hormone-dependent manner. 4-OH-2,2',3,4',5,5'-HxCB, 4,4'-diOH-3,3',5,5'-TCB and 4-OH-3,3',4',5-TCB enhanced the proliferation of GH3 cells and stimulated their production of growth hormone in the concentration range of 1 x 10 -7 to 1 x 10 -4 M, while PCBs which had no affinity for thyroid hormone receptor were inactive. In contrast, only 4-OH-2',4',6'-TCB exhibited a significant estrogenic activity using estrogen-responsive reporter assay in MCF-7 cells. However, the 3,5-dichloro substitution of 4-hydroxylated PCBs markedly decreased the estrogenic activity. These results suggest that, at least for the 17 PCB congeners and hydroxylated metabolites tested, a 4-hydroxyl group in PCBs is essential for thyroid hormonal and estrogenic activities, and that 3,5-dichloro substitution favors thyroid hormonal activity, but not estrogenic activity

  6. Expansion of microsatellite in the thyroid hormone receptor-alpha1 gene linked to increased receptor expression and less aggressive thyroid cancer

    DEFF Research Database (Denmark)

    Onda, Masamitsu; Li, Daisy; Suzuki, Shinichi

    2002-01-01

    PURPOSE: The purpose of this study was to determine whether the length of the THRA1 microsatellite, which resides in a noncoding portion of the thyroid hormone receptor-alpha1 gene, affects receptor expression and is linked to clinicopathological parameters in thyroid cancer. EXPERIMENTAL DESIGN......: In 30 cases of surgically resected sporadic thyroid cancer, the length of the THRA1 microsatellite was determined by DNA sequence analysis, and expression of thyroid hormone receptor-alpha1 was assessed immunohistochemically in thin sections cut from tumor blocks. The length of THRA1 and expression...... of thyroid hormone receptor-alpha1 were also assessed in seven cancer cell lines. Regression analysis was used to gauge the correlation between the size of THRA1 and receptor expression. Multivariate analysis was used to test for links to the clinical parameters of gender, age, histology, stage, nodal...

  7. Recent Advances in Thyroid Hormone Regulation: Toward a New Paradigm for Optimal Diagnosis and Treatment

    Directory of Open Access Journals (Sweden)

    Rudolf Hoermann

    2017-12-01

    Full Text Available In thyroid health, the pituitary hormone thyroid-stimulating hormone (TSH raises glandular thyroid hormone production to a physiological level and enhances formation and conversion of T4 to the biologically more active T3. Overstimulation is limited by negative feedback control. In equilibrium defining the euthyroid state, the relationship between TSH and FT4 expresses clusters of genetically determined, interlocked TSH–FT4 pairs, which invalidates their statistical correlation within the euthyroid range. Appropriate reactions to internal or external challenges are defined by unique solutions and homeostatic equilibria. Permissible variations in an individual are much more closely constrained than over a population. Current diagnostic definitions of subclinical thyroid dysfunction are laboratory based, and do not concur with treatment recommendations. An appropriate TSH level is a homeostatic concept that cannot be reduced to a fixed range consideration. The control mode may shift from feedback to tracking where TSH becomes positively, rather than inversely related with FT4. This is obvious in pituitary disease and severe non-thyroid illness, but extends to other prevalent conditions including aging, obesity, and levothyroxine (LT4 treatment. Treatment targets must both be individualized and respect altered equilibria on LT4. To avoid amalgamation bias, clinically meaningful stratification is required in epidemiological studies. In conclusion, pituitary TSH cannot be readily interpreted as a sensitive mirror image of thyroid function because the negative TSH–FT4 correlation is frequently broken, even inverted, by common conditions. The interrelationships between TSH and thyroid hormones and the interlocking elements of the control system are individual, dynamic, and adaptive. This demands a paradigm shift of its diagnostic use.

  8. Recent Advances in Thyroid Hormone Regulation: Toward a New Paradigm for Optimal Diagnosis and Treatment

    Science.gov (United States)

    Hoermann, Rudolf; Midgley, John E. M.; Larisch, Rolf; Dietrich, Johannes W.

    2017-01-01

    In thyroid health, the pituitary hormone thyroid-stimulating hormone (TSH) raises glandular thyroid hormone production to a physiological level and enhances formation and conversion of T4 to the biologically more active T3. Overstimulation is limited by negative feedback control. In equilibrium defining the euthyroid state, the relationship between TSH and FT4 expresses clusters of genetically determined, interlocked TSH–FT4 pairs, which invalidates their statistical correlation within the euthyroid range. Appropriate reactions to internal or external challenges are defined by unique solutions and homeostatic equilibria. Permissible variations in an individual are much more closely constrained than over a population. Current diagnostic definitions of subclinical thyroid dysfunction are laboratory based, and do not concur with treatment recommendations. An appropriate TSH level is a homeostatic concept that cannot be reduced to a fixed range consideration. The control mode may shift from feedback to tracking where TSH becomes positively, rather than inversely related with FT4. This is obvious in pituitary disease and severe non-thyroid illness, but extends to other prevalent conditions including aging, obesity, and levothyroxine (LT4) treatment. Treatment targets must both be individualized and respect altered equilibria on LT4. To avoid amalgamation bias, clinically meaningful stratification is required in epidemiological studies. In conclusion, pituitary TSH cannot be readily interpreted as a sensitive mirror image of thyroid function because the negative TSH–FT4 correlation is frequently broken, even inverted, by common conditions. The interrelationships between TSH and thyroid hormones and the interlocking elements of the control system are individual, dynamic, and adaptive. This demands a paradigm shift of its diagnostic use. PMID:29375474

  9. Increased sensitivity of thyroid hormone-mediated signaling despite prolonged fasting.

    Science.gov (United States)

    Martinez, Bridget; Scheibner, Michael; Soñanez-Organis, José G; Jaques, John T; Crocker, Daniel E; Ortiz, Rudy M

    2017-10-01

    Thyroid hormones (TH) can increase cellular metabolism. Food deprivation in mammals is typically associated with reduced thyroid gland responsiveness, in an effort to suppress cellular metabolism and abate starvation. However, in prolonged-fasted, elephant seal pups, cellular TH-mediated proteins are up-regulated and TH levels are maintained with fasting duration. The function and contribution of the thyroid gland to this apparent paradox is unknown and physiologically perplexing. Here we show that the thyroid gland remains responsive during prolonged food deprivation, and that its function and production of TH increase with fasting duration in elephant seals. We discovered that our modeled plasma TH data in response to exogenous thyroid stimulating hormone predicted cellular signaling, which was corroborated independently by the enzyme expression data. The data suggest that the regulation and function of the thyroid gland in the northern elephant seal is atypical for a fasted animal, and can be better described as, "adaptive fasting". Furthermore, the modeling data help substantiate the in vivo responses measured, providing unique insight on hormone clearance, production rates, and thyroid gland responsiveness. Because these unique endocrine responses occur simultaneously with a nearly strict reliance on the oxidation of lipid, these findings provide an intriguing model to better understand the TH-mediated reliance on lipid metabolism that is not otherwise present in morbidly obese humans. When coupled with cellular, tissue-specific responses, these data provide a more integrated assessment of thyroidal status that can be extrapolated for many fasting/food deprived mammals. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. From isolated GH deficiency to multiple pituitary hormone deficiency: an evolving continuum - a KIMS analysis

    DEFF Research Database (Denmark)

    Klose, M.; Jonsson, B.; Abs, R.

    2009-01-01

    OBJECTIVE: To describe baseline clinical presentation, treatment effects and evolution of isolated GH deficiency (IGHD) to multiple pituitary hormone deficiency (MPHD) in adult-onset (AO) GHD. DESIGN: Observational prospective study. METHODS: Baseline characteristics were recorded in 4110 patients...... with organic AO-GHD, who were GH naive prior to entry into the Pfizer International Metabolic Database (KIMS; 283 (7%) IGHD, 3827 MPHD). The effect of GH replacement after 2 years was assessed in those with available follow-up data (133 IGHD, 2207 MPHD), and development of new deficiencies in those...... with available data on concomitant medication (165 IGHD, 3006 MPHD). RESULTS: IGHD and MPHD patients had similar baseline clinical presentation, and both groups responded similarly to 2 years of GH therapy, with favourable changes in lipid profile and improved quality of life. New deficiencies were observed...

  11. Early Phthalates Exposure in Pregnant Women Is Associated with Alteration of Thyroid Hormones.

    Directory of Open Access Journals (Sweden)

    Po-Chin Huang

    Full Text Available Previous studies revealed that phthalate exposure could alter thyroid hormones during the last trimester of pregnancy. However, thyroid hormones are crucial for fetal development during the first trimester. We aimed to clarify the effect of phthalate exposure on thyroid hormones during early pregnancy.We recruited 97 pregnant women who were offered an amniocentesis during the early trimester from an obstetrics clinic in southern Taiwan from 2013 to 2014. After signing an informed consent form, we collected amniotic fluid and urine samples from pregnant women to analyze 11 metabolites, including mono-ethyl phthalate (MEP, mono-(2-ethyl-5-carboxypentyl phthalate (MECPP, mono-(2-ethylhexyl phthalate (MEHP, mono-butyl phthalate (MnBP, of 9 phthalates using liquid chromatography/ tandem mass spectrometry. We collected blood samples from each subject to analyze serum thyroid hormones including thyroxine (T4, free T4, and thyroid-binding globulin (TBG.Three phthalate metabolites were discovered to be >80% in the urine samples of the pregnant women: MEP (88%, MnBP (81% and MECPP (86%. Median MnBP and MECPP levels in pregnant Taiwanese women were 21.5 and 17.6 μg/g-creatinine, respectively, that decreased after the 2011 Taiwan DEHP scandal. Results of principal component analysis suggested two major sources (DEHP and other phthalates of phthalates exposure in pregnant women. After adjusting for age, gestational age, TBG, urinary creatinine, and other phthalate metabolites, we found a significantly negative association between urinary MnBP levels and serum T4 (β = -5.41; p-value = 0.012; n = 97 in pregnant women using Bonferroni correction.We observed a potential change in the thyroid hormones of pregnant women during early pregnancy after DnBP exposure. Additional study is necessitated to clarify these associations.

  12. Sex Differences in Brain Thyroid Hormone Levels during Early Post-Hatching Development in Zebra Finch (Taeniopygia guttata.

    Directory of Open Access Journals (Sweden)

    Shinji Yamaguchi

    Full Text Available Thyroid hormones are closely linked to the hatching process in precocial birds. Previously, we showed that thyroid hormones in brain had a strong impact on filial imprinting, an early learning behavior in newly hatched chicks; brain 3,5,3'-triiodothyronine (T3 peaks around hatching and imprinting training induces additional T3 release, thus, extending the sensitive period for imprinting and enabling subsequent other learning. On the other hand, blood thyroid hormone levels have been reported to increase gradually after hatching in altricial species, but it remains unknown how the brain thyroid hormone levels change during post-hatching development of altricial birds. Here, we determined the changes in serum and brain thyroid hormone levels of a passerine songbird species, the zebra finch using radioimmunoassay. In the serum, we found a gradual increase in thyroid hormone levels during post-hatching development, as well as differences between male and female finches. In the brain, there was clear surge in the hormone levels during development in males and females coinciding with the time of fledging, but the onset of the surge of thyroxine (T4 in males preceded that of females, whereas the onset of the surge of T3 in males succeeded that of females. These findings provide a basis for understanding the functions of thyroid hormones during early development and learning in altricial birds.

  13. Focus on growth hormone deficiency and bone in adults.

    Science.gov (United States)

    Tritos, Nicholas A

    2017-02-01

    Growth hormone (GH) exerts several effects on the skeleton, mediated either directly or indirectly, leading to increased bone formation and resorption rates. Patients with growth hormone deficiency (GHD) of adult onset have decreased bone mineral density (BMD) and increased fracture risk. Some, but not all, studies have found that adults with childhood onset GHD also have lower BMD than healthy controls. Adults with GHD of childhood onset have smaller bone dimensions, leading to possible underestimation of areal BMD (measured by dual energy X-ray absorptiometry), thus potentially confounding the interpretation of densitometric data. Available data suggest that patients with childhood onset GHD are at increased fracture risk. Prospective studies and some clinical trials found that GH replacement for at least 18-24 months leads to increased BMD. Retrospective and prospective data suggest that GH replacement is associated with decreased fracture risk in adults. However, data from randomized clinical trials are lacking. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Growth hormone deficiency in children and young adults

    Directory of Open Access Journals (Sweden)

    Joanna Oświęcimska

    2016-09-01

    Full Text Available Growth hormone (GH is a naturally occurring polypeptide hormone produced by somatotropic cells in the anterior pituitary. The main function of somatotropin is stimulation of linear growth, but it also affects carbohydrate metabolism, increases bone mass and has potent lipolytic, antinatriuretic and antidiuretic effects. Growth hormone deficiency (GHD may occur both in children and in adults. At the moment there is no gold standard for the diagnosis of GHD, and the diagnosis should take into account clinical, auxological, biochemical and radiological changes and, if necessary, genetic testing. Recent studies have highlighted that the biochemical diagnosis of GH deficiency is still imperfect. Stimuli used in the tests are non-physiological, and various substances are characterized by a different mechanism of action and potency. A few years ago it was thought that GHD treatment in children must be completed at the end of linear growth. Studies performed in the last two decades have shown that GHD deficiency in adults may result in complex clinical problems, and if untreated shortens the life expectancy and worsens its comfort. Discontinuation of GH therapy after the final height has been reached in fact negatively impacts the physiological processes associated with the transition phase, which is the period of human life between achieving the final height and 25-30 years of age. Given the adverse metabolic effects of GH treatment interruption after linear growth has been completed, the latest recommendations propose reassessment of GH secretion in the period at least one month after cessation of treatment and continuation of the therapy in case of persistent deficit.

  15. Molecular cloning, characterization and expression of thyroid-stimulating hormone receptor in channel catfish.

    Science.gov (United States)

    Goto-Kazeto, Rie; Kazeto, Yukinori; Trant, John M

    2009-05-01

    Thyroid-stimulating hormone receptors (TSHRs) are primarily expressed in the thyroid of vertebrates, however recently, transcripts encoding TSHR have been found abundantly in the gonads in a variety of fish species. The purpose of this study is to characterize the channel catfish TSHR and to examine whether the transcript are translated into protein in the gonad or store the transcript as maternal RNA for later use. The cDNA encoding the TSHR was isolated from the channel catfish thyroid but the transcript was determined to be expressed in a number of tissues, including the gonads. In fact, the ovarian expression of TSHR changed significantly during the reproductive season and peaked after the vitellogenic growth phase. Furthermore, the TSHR transcript was also detected in unfertilized eggs but not in fertilized egg of catfish. LM-PAT analysis demonstrated that catfish TSHR transcripts were fully polyadenylated in thyroidal follicles, gonads and unfertilized eggs suggesting that they were translated into protein opposed to being "stored mRNA". Western blot analysis using polyclonal antibodies against the catfish TSHR verified this assumption by visualizing immunoreactive protein in the thyroid, testis, and the post-vitellogenic ovary in abundance. A functional assay clearly showed that the recombinant catfish TSHR was specifically activated by bovine TSH but not by recombinant catfish follicle-stimulating hormone (FSH) and luteinizing hormone (LH). As in other species, the heterologous gonadotropin, hCG, partially activated the receptor. These results suggested that TSHR plays important roles for gametogenesis rather than embryogenesis.

  16. Effects of Growth Hormone Replacement Therapy on Bone Mineral Density in Growth Hormone Deficient Adults: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Peng Xue

    2013-01-01

    Full Text Available Objectives. Growth hormone deficiency patients exhibited reduced bone mineral density compared with healthy controls, but previous researches demonstrated uncertainty about the effect of growth hormone replacement therapy on bone in growth hormone deficient adults. The aim of this study was to determine whether the growth hormone replacement therapy could elevate bone mineral density in growth hormone deficient adults. Methods. In this meta-analysis, searches of Medline, Embase, and The Cochrane Library were undertaken to identify studies in humans of the association between growth hormone treatment and bone mineral density in growth hormone deficient adults. Random effects model was used for this meta-analysis. Results. A total of 20 studies (including one outlier study with 936 subjects were included in our research. We detected significant overall association of growth hormone treatment with increased bone mineral density of spine, femoral neck, and total body, but some results of subgroup analyses were not consistent with the overall analyses. Conclusions. Our meta-analysis suggested that growth hormone replacement therapy could have beneficial influence on bone mineral density in growth hormone deficient adults, but, in some subject populations, the influence was not evident.

  17. Continuation of growth hormone therapy versus placebo in transition-phase patients with growth hormone deficiency

    DEFF Research Database (Denmark)

    Jørgensen, Jens; Nørrelund, Helene; Vahl, Nina

    2002-01-01

    In a placebo-controlled, parallel study of 18 patients with a mean age of 20 years who had confirmed growth hormone (GH) deficiency, we evaluated body composition, insulin sensitivity, and glucose turnover at baseline (when all were receiving GH replacement); after 12 months of continued GH therapy...... or placebo; and after a 12-month open phase of GH therapy. In the placebo group, insulin sensitivity and fat mass increased and lipid oxidation decreased, whereas glucose oxidation increased (p...

  18. Modulating the function of the immune system by thyroid hormones and thyrotropin.

    Science.gov (United States)

    Jara, Evelyn L; Muñoz-Durango, Natalia; Llanos, Carolina; Fardella, Carlos; González, Pablo A; Bueno, Susan M; Kalergis, Alexis M; Riedel, Claudia A

    2017-04-01

    Accumulating evidence suggests a close bidirectional communication and regulation between the neuroendocrine and immune systems. Thyroid hormones (THs) can exert responses in various immune cells, e.g., monocytes, macrophages, natural killer cells, and lymphocytes, affecting several inflammation-related processes (such as, chemotaxis, phagocytosis, reactive oxygen species generation, and cytokines production). The interactions between the endocrine and immune systems have been shown to contribute to pathophysiological conditions, including sepsis, inflammation, autoimmune diseases and viral infections. Under these conditions, TH therapy could contribute to restoring normal physiological functions. Here we discuss the effects of THs and thyroid stimulating hormone (TSH) on the immune system and the contribution to inflammation and pathogen clearance, as well as the consequences of thyroid pathologies over the function of the immune system. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  19. Study protocol; Thyroid hormone Replacement for Untreated older adults with Subclinical hypothyroidism

    DEFF Research Database (Denmark)

    Stott, David J.; Gussekloo, Jacobijn; Kearney, Patricia M.

    2017-01-01

    BACKGROUND: Subclinical hypothyroidism (SCH) is a common condition in elderly people, defined as elevated serum thyroid-stimulating hormone (TSH) with normal circulating free thyroxine (fT4). Evidence is lacking about the effect of thyroid hormone treatment. We describe the protocol of a large...... in the placebo group. The primary outcomes are changes in two domains (hypothyroid symptoms and fatigue / vitality) on the thyroid-related quality of life questionnaire (ThyPRO) at one year. The study has 80% power (at p = 0.025, 2-tailed) to detect a change with levothyroxine treatment of 3.......0% on the hypothyroid scale and 4.1% on the fatigue / vitality scale with a total target sample size of 750 patients. Secondary outcomes include general health-related quality of life (EuroQol), fatal and non-fatal cardiovascular events, handgrip strength, executive cognitive function (Letter Digit Coding Test), basic...

  20. New Approaches to Assess the Transthyretin Binding Capacity of Bioactivated Thyroid Hormone Disruptors

    NARCIS (Netherlands)

    Montano, M.; Cocco, E.; Guignard, C.; Marsh, G.; Hoffmann, L.; Bergman, A.; Gutleb, A.C.; Murk, A.J.

    2012-01-01

    Polychlorinated biphenyls (PCBs) and polybrominated diphenyl-ethers (PBDEs) are metabolized into hydroxylated metabolites (OH-PCBs/PBDEs), which can disrupt the thyroid hormone homeostasis. Binding of these metabolites to transport proteins such as transthyretin (TTR) is an important mechanism of

  1. Thyroid Hormone Levels and Psychological Symptoms in Sexually Abused Adolescent Girls

    Science.gov (United States)

    Haviland, Mark G.; Sonne, Janet L.; Anderson, Donald L.; Nelson, Jerald C.; Sheridan-Matney, Clare; Nichols, Joy G.; Carlton, Esther I.; Murdoch, William G. C.

    2006-01-01

    Objective: To explore the relationships between psychological symptoms and thyroid hormone levels in adolescent girls who had experienced the traumatic stress of sexual abuse. Method: The study design was cross-sectional/correlational. Subjects ("N"=22; age range=12-18 years) had their blood drawn, and they completed 2 psychological tests…

  2. The role of Arg445 and Asp498 in the human thyroid hormone transporter MCT8

    NARCIS (Netherlands)

    S. Groeneweg (Stefan); E.C.H. Friesema (Edith); S. Kersseboom (Simone); W. Klootwijk (Willem); W.E. Visser (Wil Edward); R.P. Peeters (Robin); T.J. Visser (Theo)

    2014-01-01

    textabstractMonocarboxylate transporter 8 (MCT8) facilitates cellular influx and efflux of the thyroid hormones (THs) T4 and T3. Mutations in MCT8 lead to severe psychomotor retardation. Here, we studied the importance of 2 highly conserved residues (Arg445 in transmembrane domain 8 and Asp498 in

  3. Mutations in Thyroid Hormone Transporter MCT8: genotype, function and phenotype

    NARCIS (Netherlands)

    J. Jansen (Jurgen)

    2008-01-01

    textabstractThe studies presented in this thesis demonstrate that MCT8 is a transmembrane protein that facilitates both in- and efflux of thyroid hormone. MCT8 function is crucial for normal neurological development, as loss-of-function mutations are associated with severe psychomotor retardation.

  4. Genotype-phenotype relationship in patients with mutations in thyroid hormone transporter MCT8

    NARCIS (Netherlands)

    J.A. Jansen (John); E.C.H. Friesema (Edith); M.H.A. Kester (Monique); C.E. Schwartz; T.J. Visser (Theo)

    2008-01-01

    textabstractLoss-of-function mutations in thyroid hormone transporter monocarboxylate transporter 8 (MCT8) lead to severe X-linked psychomotor retardation and elevated serum T3levels. Most patients, for example those with mutations V235M, S448X, insI189, or delF230, cannot stand, walk, or speak.

  5. Impairment of iodine and thyroid hormone metabolism in very premature infants

    Czech Academy of Sciences Publication Activity Database

    Pavelka, Stanislav

    2008-01-01

    Roč. 24, Suppl.1 (2008), S46-S47 ISSN 0742-2091. [Trace Elements in Diet, Nutrition and Health. 21.10.2008-26.10.2008, Hersonissos] Institutional research plan: CEZ:AV0Z50110509 Keywords : cpo1 * newborn * iodine * thyroid hormone Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition

  6. Trialkyltin rexinoid-X receptor agonists selectively potentiate thyroid hormone induced programs of xenopus laevis metamorphosis

    NARCIS (Netherlands)

    Mengeling, Brenda J.; Murk, Albertinka J.; Furlow, J.D.

    2016-01-01

    The trialkyltins tributyltin (TBT) and triphenyltin (TPT) can function as rexinoid-X receptor (RXR) agonists. We recently showed that RXR agonists can alter thyroid hormone (TH) signaling in a mammalian pituitary TH-responsive reporter cell line, GH3.TRE-Luc. The prevalence of TBT and TPT in the

  7. Functional and metabolic adaptation of the heart to prolonged thyroid hormone treatment.

    NARCIS (Netherlands)

    Degens, H.; Gilde, A.J.; Lindhout, M.; Willemsen, P.H.; Vusse, G.J. van der; Bilsen, M. van

    2003-01-01

    In heart failure, thyroid hormone (TH) treatment improves cardiac performance. The long-term effects of TH on cardiac function and metabolism, however, are incompletely known. To investigate the effects of up to 28 days of TH treatment, male Wistar rats received 3,3',5-triiodo-l-thyronine (200

  8. Transporters MCT8 and OATP1C1 maintain murine brain thyroid hormone homeostasis

    NARCIS (Netherlands)

    Mayerl, Steffen; Müller, Julia; Bauer, Reinhard; Richert, Sarah; Kassmann, Celia M.; Darras, Veerle M.; Buder, Katrin; Boelen, Anita; Visser, Theo J.; Heuer, Heike

    2014-01-01

    Allan-Herndon-Dudley syndrome (AHDS), a severe form of psychomotor retardation with abnormal thyroid hormone (TH) parameters, is linked to mutations in the TH-specific monocarboxylate transporter MCT8. In mice, deletion of Mct8 (Mct8 KO) faithfully replicates AHDS-associated endocrine abnormalities;

  9. Analysis of Agonist and Antagonist Effects on Thyroid Hormone Receptor Conformation by Hydrogen/Deuterium Exchange

    NARCIS (Netherlands)

    Figueira, A C M; Saidemberg, D M; Telles de Souza, Paulo; Martínez, L; Scanlan, T S; Baxter, J D; Skaf, M S; Palma, M S; Webb, P M; Polikarpov, I

    Thyroid hormone receptors (TRs) are ligand-gated transcription factors with critical roles in development and metabolism. Although x-ray structures of TR ligand-binding domains (LBDs) with agonists are available, comparable structures without ligand (apo-TR) or with antagonists are not. It remains

  10. Polychlorinated biphenyl-induced alterations of thyroid hormone homeostasis and brain development in the rat

    NARCIS (Netherlands)

    Morse, D.C.

    1995-01-01

    Introduction

    The work described in this thesis was undertaken to gain insight in the processes involved in the developmental neurotoxicity of polychlorinated biphenyls. It has been previously hypothesized that the alteration of thyroid hormone status by PCBs may

  11. Thyroid hormone receptor isoform expression in livers of critically ill patients

    NARCIS (Netherlands)

    Thijssen-Timmer, Daphne C.; Peeters, Robin P.; Wouters, Pieter; Weekers, Frank; Visser, Theo J.; Fliers, Eric; Wiersinga, Wilmar M.; Bakker, Onno; Berghe, Greet Van Den

    2007-01-01

    OBJECTIVE: The THRA gene encodes two isoforms of the thyroid hormone receptor (TR), TRalpha1 and TRalpha2. The ratio of these splice variants could have a marked influence on T3-regulated gene expression, especially during illness. DESIGN: We studied the expression of the isoforms TRbeta1, TRalpha1,

  12. PCB153 disrupts thyroid hormone homeostasis by affecting its biosynthesis, biotransformation, feedback regulation, and metabolism.

    Science.gov (United States)

    Liu, C; Wang, C; Yan, M; Quan, C; Zhou, J; Yang, K

    2012-09-01

    PCB153, one of the 3 dominant congeners in the food chain, causes the disruption of the endocrine system in humans and animals. In order to elucidate the effects of PCB153 on the biosynthesis, biotransformation, regulation, metabolism, and transport of thyroid hormones (THs), Sprague-Dawley (SD) rats were dosed with PCB153 intraperitoneally (i.p.) at 0, 4, 16 and 32 mg/kg/day for 5 consecutive days and sacrificed 24 h after the last dose. Results showed that after treatment with PCB153, serum total thyroxine (TT4), total triiodothyronine (TT3), and thyrotropin releasing hormone (TRH) decreased, whereas serum thyroid stimulating hormone (TSH) concentration did not alter. The serum sodium iodide symporter (NIS), thyroid peroxidase (TPO), and thyroglobulin (Tg) levels decreased. The mRNA expressions of type 2 and 3 deiodinases (D2 and D3) reduced, but the type 1 deiodinase (D1) showed no significant change. The TSH receptor (TSHr) and TRH receptor (TRHr) levels declined. PCB153 induced hepatic enzymes, and the UDPGTs, CYP2B1, and CYP3A1 mRNA levels were significantly elevated. Taken together, the observed results from the present study indicated that PCB153 disrupted thyroid hormone homeostasis through influencing synthesis-associated proteins (NIS, TPO and Tg), deiodinases, receptors (TSHr and TRHr), and hepatic enzymes, and the decrease of D3 expression might be the compensatory response of body. © Georg Thieme Verlag KG Stuttgart · New York.

  13. Thyroid hormones correlate with resting metabolic rate, not daily energy expenditure, in two charadriiform seabirds

    Directory of Open Access Journals (Sweden)

    Kyle H. Elliott

    2013-04-01

    Thyroid hormones affect in vitro metabolic intensity, increase basal metabolic rate (BMR in the lab, and are sometimes correlated with basal and/or resting metabolic rate (RMR in a field environment. Given the difficulty of measuring metabolic rate in the field—and the likelihood that capture and long-term restraint necessary to measure metabolic rate in the field jeopardizes other measurements—we examined the possibility that circulating thyroid hormone levels were correlated with RMR in two free-ranging bird species with high levels of energy expenditure (the black-legged kittiwake, Rissa tridactyla, and thick-billed murre, Uria lomvia. Because BMR and daily energy expenditure (DEE are purported to be linked, we also tested for a correlation between thyroid hormones and DEE. We examined the relationships between free and bound levels of the thyroid hormones thyroxine (T4 and triiodothyronine (T3 with DEE and with 4-hour long measurements of post-absorptive and thermoneutral resting metabolism (resting metabolic rate; RMR. RMR but not DEE increased with T3 in both species; both metabolic rates were independent of T4. T3 and T4 were not correlated with one another. DEE correlated with body mass in kittiwakes but not in murres, presumably owing to the larger coefficient of variation in body mass during chick rearing for the more sexually dimorphic kittiwakes. We suggest T3 provides a good proxy for resting metabolism but not DEE in these seabird species.

  14. Thyroid hormone transport and metabolism by OATP1C1 and consequences of genetic variation

    DEFF Research Database (Denmark)

    van der Deure, Wendy M; Hansen, Pia Skov; Peeters, Robin P

    2008-01-01

    OATP1C1 has been characterized as a specific thyroid hormone transporter. Based on its expression in capillaries in different brain regions, OATP1C1 is thought to play a key-role in transporting thyroid hormone across the blood-brain barrier. For this reason, we studied the specificity of iodothy......OATP1C1 has been characterized as a specific thyroid hormone transporter. Based on its expression in capillaries in different brain regions, OATP1C1 is thought to play a key-role in transporting thyroid hormone across the blood-brain barrier. For this reason, we studied the specificity...... with TH levels, nor did they affect transport function in vitro. In conclusion, OATP1C1 mediates transport of T4, T4S and rT3 and increases the access of these substrates to the intracellular active sites of the deiodinases. No effect of genetic variation on the function of OATP1C1 was observed....

  15. Effects of experimentally manipulated yolk thyroid hormone levels on offspring development in a wild bird species

    NARCIS (Netherlands)

    Ruuskanen, Suvi; Darras, Veerle M; Visser, Marcel E; Groothuis, Antonius

    2016-01-01

    Maternal effects are a crucial mechanism in a wide array of taxa to generate phenotypic variation, thereby affecting offspring development and fitness. Maternally derived thyroid hormones (THs) are known to be essential for offspring development in mammalian and fish models, but have been largely

  16. Effects of experimentally manipulated yolk thyroid hormone levels on offspring development in a wild bird species

    NARCIS (Netherlands)

    Ruuskanen, Suvi; Darras, Veerle M.; Visser, Marcel E.; Groothuis, Ton G.G.

    Abstract Maternal effects are a crucial mechanism in a wide array of taxa to generate phenotypic variation, thereby affecting offspring development and fitness. Maternally derived thyroid hormones (THs) are known to be essential for offspring development in mammalian and fish models, but have been

  17. Thyroid hormone signaling: Contribution to neural function, cognition, and relationship to nicotine.

    Science.gov (United States)

    Leach, Prescott T; Gould, Thomas J

    2015-10-01

    Cigarette smoking is common despite its adverse effects on health, such as cardiovascular disease and stroke. Understanding the mechanisms that contribute to the addictive properties of nicotine makes it possible to target them to prevent the initiation of smoking behavior and/or increase the chance of successful quit attempts. While highly addictive, nicotine is not generally considered to be as reinforcing as other drugs of abuse. There are likely other mechanisms at work that contribute to the addictive liability of nicotine. Nicotine modulates aspects of the endocrine system, including the thyroid, which is critical for normal cognitive functioning. It is possible that nicotine's effects on thyroid function may alter learning and memory, and this may underlie some of its addictive potential. Here, we review the literature on thyroid function and cognition, with a focus on how nicotine alters thyroid hormone signaling and the potential impact on cognition. Changes in cognition are a major symptom of nicotine addiction. Current anti-smoking therapies have modest success at best. If some of the cognitive effects of nicotine are mediated through the thyroid hormone system, then thyroid hormone agonists may be novel treatments for smoking cessation therapies. The content of this review is important because it clarifies the relationship between smoking and thyroid function, which has been ill-defined in the past. This review is timely because the reduction in smoking rates we have seen in recent decades, due to public awareness campaigns and public smoking bans, has leveled off in recent years. Therefore, novel treatment approaches are needed to help reduce smoking rates further. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Treatment with Growth Hormone for Adults with Growth Hormone Deficiency Syndrome: Benefits and Risks

    Science.gov (United States)

    Díez, Juan J.; Sangiao-Alvarellos, Susana; Cordido, Fernando

    2018-01-01

    Pharmacological treatment of growth hormone deficiency (GHD) in adults began in clinical practice more than 20 years ago. Since then, a great volume of experience has been accumulated on its effects on the symptoms and biochemical alterations that characterize this hormonal deficiency. The effects on body composition, muscle mass and strength, exercise capacity, glucose and lipid profile, bone metabolism, and quality of life have been fully demonstrated. The advance of knowledge has also taken place in the biological and molecular aspects of the action of this hormone in patients who have completed longitudinal growth. In recent years, several epidemiological studies have reported interesting information about the long-term effects of GH replacement therapy in regard to the possible induction of neoplasms and the potential development of diabetes. In addition, GH hormone receptor polymorphism could potentially influence GH therapy. Long-acting GH are under development to create a more convenient GH dosing profile, while retaining the excellent safety, efficacy, and tolerability of daily GH. In this article we compile the most recent data of GH replacement therapy in adults, as well as the molecular aspects that may condition a different sensitivity to this treatment. PMID:29562611

  19. Mechanisms of crosstalk between endocrine systems: regulation of sex steroid hormone synthesis and action by thyroid hormones.

    Science.gov (United States)

    Duarte-Guterman, Paula; Navarro-Martín, Laia; Trudeau, Vance L

    2014-07-01

    Thyroid hormones (THs) are well-known regulators of development and metabolism in vertebrates. There is increasing evidence that THs are also involved in gonadal differentiation and reproductive function. Changes in TH status affect sex ratios in developing fish and frogs and reproduction (e.g., fertility), hormone levels, and gonad morphology in adults of species of different vertebrates. In this review, we have summarized and compared the evidence for cross-talk between the steroid hormone and thyroid axes and present a comparative model. We gave special attention to TH regulation of sex steroid synthesis and action in both the brain and gonad, since these are important for gonad development and brain sexual differentiation and have been studied in many species. We also reviewed research showing that there is a TH system, including receptors and enzymes, in the brains and gonads in developing and adult vertebrates. Our analysis shows that THs influences sex steroid hormone synthesis in vertebrates, ranging from fish to pigs. This concept of crosstalk and conserved hormone interaction has implications for our understanding of the role of THs in reproduction, and how these processes may be dysregulated by environmental endocrine disruptors. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Molecular mechanisms of regulation of growth hormone gene expression in cultured rat pituitary cells by thyroid and glucocorticoid hormones

    International Nuclear Information System (INIS)

    Yaffe, B.M.

    1989-01-01

    In cultured GC cells, a rat pituitary tumor cell line, growth hormone [GH] is induced in a synergistic fashion by physiologic concentrations of thyroid and glucocorticoid hormones. Abundant evidence indicates that these hormones mediate this response via their specific receptors. The purpose of this thesis is to explore the mechanisms by which these hormones affect GH production. When poly (A) + RNA was isolated from cells grown both with and without hormones and translated in a cell-free wheat germ system, the preGH translation products were shown to be proportional to immunoassayable GH production under all combinations of hormonal milieux, indicating that changes in GH production is modulated at a pretranslational level. A cDNA library was constructed from poly (A) + RNA and one clone containing GH cDNA sequences was isolated. This was used to confirm the above results by Northern dot blot analysis. This probe was also used to assess hormonal effects on GH mRNA half-life and synthetic rates as well as GH gene transcription rates in isolated nuclei. Using a pulse-chase protocol in which cellular RNA was labeled in vivo with [ 3 H]uridine, and quantitating [ 3 H]GHmRNA directly by hybridization to GH cDNA bound to nitrocellulose filters, GHmRNA was found to have a half-life of approximately 50 hours, and was not significantly altered by the presence of inducing hormones

  1. Ovine thyroid stimulating hormone (TSH) heterologously stimulates production of thyroid hormones from Chinese soft-shell turtle (Pelodiscus sinensis) and bullfrog (Rana catesbeiana and Rana rugulosa) thyroids in vitro.

    Science.gov (United States)

    Huang, Wei-Tung; Chien, Jung-Tsun; Weng, Ching-Feng; Jeng, Yung-Yue; Lu, Li-Chia; Yu, John Yuh-Lin

    2009-06-01

    Thyroid hormones are important for regulating a variety of developmental processes in vertebrates, including growth, differentiation, metamorphosis, and oxidative metabolism. In particular, this study focused on the in vitro production of thyroxine (T(4)) and triiodothyronine (T(3)) from thyroids in American bullfrogs (Rana catesbeiana), Chinese bullfrogs (Rana rugulosa Wiegmann), and Chinese soft-shell turtles (Pelodiscus sinensis) treated with ovine thyroid stimulating hormone (TSH) at different culture intervals (2, 4, 8, and 12 h) and dosages (1, 10, 50 or 100 ng). The levels of T(4) and T(3) in the tested animals were elevated upon stimulation in a time- and dose-dependent manner, indicating de novo synthesis of T(4) and T(3). Significantly higher hormone levels were observed in the Chinese bullfrog compared to the other two species, for both the time-course and dose-response experiments. Although the bullfrog secreted significantly higher levels of T(4) and T(3), a higher T(4)-conversion capacity was found in the Chinese soft-shell turtle. The highest ratios of T(3) to T(4) were observed in the American bullfrog and Chinese soft-shell turtle for the time-course and dose-response experiments, respectively. These findings suggest that the Chinese soft-shell turtle and bullfrog thyroids can accept ovine TSH for T(4)- and T(3)-formation in a time- and dose-dependent manner, supporting the hypothesis that the binding interactions between TSHs and thyroidal receptors are conserved in vertebrates.

  2. Imbalance between thyroid hormones and the dopaminergic system might be central to the pathophysiology of restless legs syndrome: a hypothesis

    Directory of Open Access Journals (Sweden)

    Jose Carlos Pereira Jr.

    2010-01-01

    Full Text Available Data collected from medical literature indicate that dopaminergic agonists alleviate Restless Legs Syndrome symptoms while dopaminergic agonists antagonists aggravate them. Dopaminergic agonists is a physiological regulator of thyroid-stimulating hormone. Dopaminergic agonists infusion diminishes the levels of thyroid hormones, which have the ability to provoke restlessness, hyperkinetic states, tremors, and insomnia. Conditions associated with higher levels of thyroid hormones, such as pregnancy or hyperthyroidism, have a higher prevalence of Restless Legs Syndrome symptoms. Low iron levels can cause secondary Restless Legs Syndrome or aggravate symptoms of primary disease as well as diminish enzymatic activities that are involved in dopaminergic agonists production and the degradation of thyroid hormones. Moreover, as a result of low iron levels, dopaminergic agonists diminishes and thyroid hormones increase. Iron therapy improves Restless Legs Syndrome symptoms in iron deprived patients. Medical hypothesis. To discuss the theory that thyroid hormones, when not counterbalanced by dopaminergic agonists, may precipitate the signs and symptoms underpinning Restless Legs Syndrome. The main cause of Restless Legs Syndrome might be an imbalance between the dopaminergic agonists system and thyroid hormones.

  3. THE INFLUENCE OF END-STAGE LIVER DISEASE AND LIVER TRANSPLANTATION ON THYROID HORMONES

    Directory of Open Access Journals (Sweden)

    Karla Rocha PENTEADO

    Full Text Available Background Thyroid dysfunction has been reported in most chronic illnesses including severe liver disease. These defects in thyroid hormone metabolism result in the sick euthyroid syndrome, also known as low T3 syndrome. Objectives Our objective was to evaluate the thyroid function in patients with end stage liver disease prior and after deceased donor liver transplantation and to correlate thyroid hormonal changes with the MELD score (Model for End stage Liver Disease. Methods In a prospective study, serum levels of thyrotropin (thyroid stimulating hormone TSH, total thyroxine (tT4, free thyroxine (fT4 and triiodothyronine (T3 from 30 male adult patients with end stage liver disease were measured two to four hours before and 6 months after liver transplantation (LT. MELD was determined on the day of transplant. For this analysis, extra points were not added for patients with hepatocellular carcinoma. Results The patients had normal TSH and fT4 levels before LT and there was no change after the procedure. Total thyroxine and triiodothyronine were within the normal range before LT, except for four patients (13.3% whose values were lower. Both hormones increased to normal values in all four patients after LT (P=0.02 and P18, it was observed that there was no change in the TSH, freeT4, and total T4 levels in both groups after LT. Although there was no significant variation in the level of T3 in MELD 18 group after LT (P=0.003. Conclusion Patients with end stage liver disease subjected to liver transplantation had normal TSH and fT4 levels before and after LT. In a few patients with lower tT4 and T3 levels before LT, the level of these hormones increased to normal after LT.

  4. The influence of end-stage liver disease and liver transplantation on thyroid hormones.

    Science.gov (United States)

    Penteado, Karla Rocha; Coelho, Júlio Cezar Uili; Parolin, Mônica Beatriz; Matias, Jorge Eduardo Fouto; Freitas, Alexandre Coutinho Teixeira de

    2015-01-01

    Thyroid dysfunction has been reported in most chronic illnesses including severe liver disease. These defects in thyroid hormone metabolism result in the sick euthyroid syndrome, also known as low T3 syndrome. Our objective was to evaluate the thyroid function in patients with end stage liver disease prior and after deceased donor liver transplantation and to correlate thyroid hormonal changes with the MELD score (Model for End stage Liver Disease). In a prospective study, serum levels of thyrotropin (thyroid stimulating hormone TSH), total thyroxine (tT4), free thyroxine (fT4) and triiodothyronine (T3) from 30 male adult patients with end stage liver disease were measured two to four hours before and 6 months after liver transplantation (LT). MELD was determined on the day of transplant. For this analysis, extra points were not added for patients with hepatocellular carcinoma. The patients had normal TSH and fT4 levels before LT and there was no change after the procedure. Total thyroxine and triiodothyronine were within the normal range before LT, except for four patients (13.3%) whose values were lower. Both hormones increased to normal values in all four patients after LT (P=0.02 and P18), it was observed that there was no change in the TSH, freeT4, and total T4 levels in both groups after LT. Although there was no significant variation in the level of T3 in MELD 18 group after LT (P=0.003). Patients with end stage liver disease subjected to liver transplantation had normal TSH and fT4 levels before and after LT. In a few patients with lower tT4 and T3 levels before LT, the level of these hormones increased to normal after LT.

  5. A survey on relationships between thyroid hormone levels and clinical findings in dairy calf diarrhea

    Directory of Open Access Journals (Sweden)

    Ali Hajimohammadi

    2015-03-01

    Full Text Available Calf diarrhea is an important disease that occurs in association with the interaction of various infectious agents and calf susceptibility. The economic losses is associated with death loss and treatment costs, reduction of live weight gain, and reduction of productive life span, which may be considerable. Thyroid hormones previously thought mainly in thermoregulation and energy metabolism. Recently, several studies have challenged on their roles in the metabolic response of animals to certain conditions such as nutritional, environmental, or disease state. The aim of the present study was to survey relationships between thyroid hormones in calves with diarrhea in the different clinical features. Holstein calves (50 within 1 day to 2 months old with signs of diarrhea and healthy calves (40 with similar age and sex were selected. Standard clinical examinations and also dehydration degree assessment were carried out on each calf and recorded accordingly. Calves with clinical signs of diarrhea were divided in different groups based on the severity of the clinical findings, fever and degree of dehydration. Blood samples were taken from the jugular vein from all calves into vacutainer tubes for serum collection.T4, fT4, T3 and fT3 concentrations were measured by validated methods. A significant increase in T4, T3 and fT3 in diarrheic calves was observed (P<0.05. Thyroid hormones in calves with severe clinical signs decreased significantly (P<0.001 compared to calves with moderate or mild systemic clinical signs. Thyroid hormones between febrile diarrheic calves compared to afebrile diarrheic calves had no significant changes. Diarrheic calves with severe dehydration compared to diarrheic calves with mild and moderate dehydration had significant decreases in their thyroid hormones (P<0.001.

  6. Smith-Magenis syndrome and growth hormone deficiency.

    Science.gov (United States)

    Spadoni, Emanuela; Colapietro, Patrizia; Bozzola, Mauro; Marseglia, Gian L; Repossi, Luciana; Danesino, Cesare; Larizza, Lidia; Maraschio, Paola

    2004-07-01

    Smith-Magenis syndrome (SMS) is a multiple congenital anomaly/mental retardation syndrome including physical and neurobehavioural features. The disease is commonly associated with a ca. 3.7 Mb interstitial deletion of chromosome 17p11.2, while a 1.1 Mb critical region has been identified, containing about 20 genes expressed in multiple tissues. Haploinsufficiency of one of them, RAI1, seems to be responsible for the neurobehavioural, craniofacial and otolaryngological features of the syndrome, but not for short stature, commonly seen in SMS patients with chromosome deletion, implying the role of other genes in the 17p11.2 region. Growth failure is a final result of several different mechanisms involving decreased growth hormone (GH) production, reduced tissue response to GH, or impaired activity of epistatic factors. To our knowledge, the association of GH deficiency with SMS has never been reported and rarely investigated, despite the very short stature of SMS patients. We describe a girl with a full SMS phenotype and a typical 3.7 Mb deletion of 17p11.2 who also has GH deficiency. After starting replacement therapy, growth has significantly improved, her stature being now above both the 10th percentile and her genetic target. we suggest that an investigation of both growth hormone secretion and function is carried out in patients with Smith-Magenis syndrome and 17p11.2 deletion. Copyright 2004 Springer-Verlag

  7. Thyroid Hormone Therapy for Older Adults with Subclinical Hypothyroidism

    DEFF Research Database (Denmark)

    Stott, David J.; Rodondi, Nicolas; Kearney, Patricia M.

    2017-01-01

    if the body weight was disease), with dose adjustment according to thethyrotropin level; 369 patients were assigned to receive placebo with mock dose adjustment. The two primary outcomes were the change in the Hypothyroid Symptomsscore and Tiredness score on a thyroid...

  8. Thyroid hormone uptake by rat hepatocytes in primary culture

    NARCIS (Netherlands)

    E.P. Krenning (Eric)

    1983-01-01

    textabstractIodide is taken up by the thyroid follicular cell, oxydized and bound to thyroglobulin at the apical membrane facing the colloid in the follicular lumen. Iodinated colloid is subsequently engulfed by the follicular cell and hydrolysed, liberating thyroxine and triiodothyronine from their

  9. Assessing Waste Water Treatment Plant Effluent for Thyroid Hormone Disruption

    Science.gov (United States)

    Much information has been coming to light on the estrogenic and androgenic activity of chemicals present in the waste water stream and in surface waters, but much less is known about the presence of chemicals with thyroid activity. To address this issue, we have utilized two assa...

  10. Impaired transport of thyroid hormones into livers of obese (ob/ob) mice

    International Nuclear Information System (INIS)

    Hillgartner, F.B.; Romsos, D.R.

    1988-01-01

    Obese (ob/ob) mice exhibit impaired hepatic thyroid hormone action that is mediated, at least in part, by a reduced nuclear 3,5,3'-triiodothyronine (T 3 ) receptor occupancy. The possibility that lowered occupancy in obese mice may be caused by decreased transport of T 3 across the hepatic plasma membrane was examined by measuring the unidirectional influx of [ 125 I]T 3 into livers of 8- to 10-wk-old obese and lean mice using a tissue-sampling portal vein-injection technique. Influx of [ 125 I]thyroxine (T 4 ), a substrate for T 4 5'-deiodinase, was also measured. Unidirectional clearance of T 3 and T 4 was 64 and 80% lower, respectively, in obese mice than in lean mice. Hepatic T 3 and T 4 uptake was nonsaturable in both lean and obese mice, suggesting that transport occurs by lipid-mediated free diffusion. Clearance of another lipid-soluble hormone, hydrocortisone, was also lower in obese mice than in lean mice. Decreased membrane permeability to the above hormones in obese mice may result from reported changes in membrane lipid composition. In conclusion, decreased hepatic thyroid hormone uptake may contribute to impaired thyroid hormone action and T 3 production in livers of obese mice

  11. Association between organophosphate pesticides exposure and thyroid hormones in floriculture workers.

    Science.gov (United States)

    Lacasaña, Marina; López-Flores, Inmaculada; Rodríguez-Barranco, Miguel; Aguilar-Garduño, Clemente; Blanco-Muñoz, Julia; Pérez-Méndez, Oscar; Gamboa, Ricardo; Bassol, Susana; Cebrian, Mariano E

    2010-02-15

    The ability of organophosphate pesticides to disturb thyroid gland function has been demonstrated by experimental studies on animal, but evidence of such effects on human remains scarce. The aim of this study was to assess the association between exposure to organophosphate compounds and serum levels of thyroid hormones in floriculture workers. A longitudinal study was conducted on 136 male subjects from the State of Mexico and Morelos, Mexico, occupationally exposed to organophosphate pesticides, during agricultural periods of high (rainy season) and low (dry season) levels of pesticide application. Using a structured questionnaire, a survey was carried out on sociodemographic characteristics, anthropometry, clinical history, alcohol and tobacco consumption, residential chemical exposure, and occupational history. Urine and blood samples were taken the day after pesticide application to determine urine dialkylphosphate (DAP) levels, serum levels of TSH, total T(3), total T(4), serum PON1 activity, and serum p,p'-DEE levels. The analysis of the association between DAP levels and thyroid hormonal profile was carried out using multivariate generalized estimating equation (GEE) models. Our results showed an increase in both TSH and T(4) hormones in serum associated with a increase in total dimethylphosphate levels (SigmaDMP) in urine (p-trendorganophosphate pesticides may be responsible of increasing TSH and T(4) serum hormone levels and decreasing T(3) serum hormone levels, therefore supporting the hypothesis that organophosphate pesticides act as endocrine disruptors in humans. Copyright 2009 Elsevier Inc. All rights reserved.

  12. EVALUATION OF THYROID HORMONES AND AS INFLUENCED BY TREATMENT WITH DESLORELIN IN PALLAS' CATS (OTOCOLOBUS (FELIS) MANUL).

    Science.gov (United States)

    Delaski, Kristina M; Gamble, Kathryn C

    2015-12-01

    Thyroid hormones regulate a variety of physiologic functions including metabolism, growth, and reproductive cycling, and these other hormones can impact the thyroid function via the hypothalamic-pituitary axis. For instance, the gonadotropin-releasing hormone agonist, deslorelin, used in nondomestic carnivores for contraception and behavioral control, down-regulates reproductive hormones through this mechanism and so may impact thyroid function. Due to clinical concerns of hypothyroidism in a bachelor group of adult male Pallas' cats (Otocolobus (Felis) manul) which also had deslorelin implants, serum samples from treated captive (n = 8) individuals, untreated captive (n = 25), and free-ranging (n = 9) individuals were analyzed for thyroid hormone concentrations. Total and free thyroxine (TT4 and FT4), total and free tri-iodothyronine (TT3 and FT3), and thyroid stimulating hormone (TSH) were measured although, due to sample volume limitations, not every hormone could be analyzed for every sample. Of these hormones, only FT4 was found statistically different between the deslorelin-treated and untreated groups. As samples were unevenly distributed across season, true comparison between seasons could not be made. The values reported for the untreated captive and free-ranging group, while representing a small sample size, can serve as a baseline assessment when evaluating the thyroid status of captive Pallas' cats.

  13. Thyroid volume and urinary iodine in European schoolchildren: standardization of values for assessment of iodine deficiency

    NARCIS (Netherlands)

    Delange, F.; Benker, G.; Caron, P.; Eber, O.; Ott, W.; Peter, F.; Podoba, J.; Simescu, M.; Szybinsky, Z.; Vertongen, F.; Vitti, P.; Wiersinga, W.; Zamrazil, V.

    1997-01-01

    Up to 1992, most European countries used to be moderately to severely iodine deficient. The present study aimed at evaluating possible changes in the status of iodine nutrition in 12 European countries during the past few years. Thyroid volume was measured by ultrasonography in 7599 schoolchildren

  14. Multiple steroid and thyroid hormones detected in baleen from eight whale species.

    Science.gov (United States)

    Hunt, Kathleen E; Lysiak, Nadine S; Robbins, Jooke; Moore, Michael J; Seton, Rosemary E; Torres, Leigh; Buck, C Loren

    2017-01-01

    Recent studies have demonstrated that some hormones are present in baleen powder from bowhead ( Balaena mysticetus) and North Atlantic right ( Eubalaena glacialis ) whales. To test the potential generalizability of this technique for studies of stress and reproduction in large whales, we sought to determine whether all major classes of steroid and thyroid hormones are detectable in baleen, and whether these hormones are detectable in other mysticetes. Powdered baleen samples were recovered from single specimens of North Atlantic right, bowhead, blue ( Balaenoptera [ B .] musculus ), sei ( B. borealis ), minke ( B. acutorostrata ), fin ( B. physalu s), humpback ( Megaptera novaeangliae ) and gray ( Eschrichtius robustus ) whales. Hormones were extracted with a methanol vortex method, after which we tested all species with commercial enzyme immunoassays (EIAs, Arbor Assays) for progesterone, testosterone, 17β-estradiol, cortisol, corticosterone, aldosterone, thyroxine and tri-iodothyronine, representing a wide array of steroid and thyroid hormones of interest for whale physiology research. In total, 64 parallelism tests (8 species × 8 hormones) were evaluated to verify good binding affinity of the assay antibodies to hormones in baleen. We also tested assay accuracy, although available sample volume limited this test to progesterone, testosterone and cortisol. All tested hormones were detectable in baleen powder of all species, and all assays passed parallelism and accuracy tests. Although only single individuals were tested, the consistent detectability of all hormones in all species indicates that baleen hormone analysis is likely applicable to a broad range of mysticetes, and that the EIA kits tested here perform well with baleen extract. Quantification of hormones in baleen may be a suitable technique with which to explore questions that have historically been difficult to address in large whales, including pregnancy and inter-calving interval, age of sexual

  15. Transcriptional activation by the thyroid hormone receptor through ligand-dependent receptor recruitment and chromatin remodelling

    DEFF Research Database (Denmark)

    Grøntved, Lars; Waterfall, Joshua J; Kim, Dong Wook

    2015-01-01

    A bimodal switch model is widely used to describe transcriptional regulation by the thyroid hormone receptor (TR). In this model, the unliganded TR forms stable, chromatin-bound complexes with transcriptional co-repressors to repress transcription. Binding of hormone dissociates co-repressors and......A bimodal switch model is widely used to describe transcriptional regulation by the thyroid hormone receptor (TR). In this model, the unliganded TR forms stable, chromatin-bound complexes with transcriptional co-repressors to repress transcription. Binding of hormone dissociates co......-repressors and facilitates recruitment of co-activators to activate transcription. Here we show that in addition to hormone-independent TR occupancy, ChIP-seq against endogenous TR in mouse liver tissue demonstrates considerable hormone-induced TR recruitment to chromatin associated with chromatin remodelling and activated...... gene transcription. Genome-wide footprinting analysis using DNase-seq provides little evidence for TR footprints both in the absence and presence of hormone, suggesting that unliganded TR engagement with repressive complexes on chromatin is, similar to activating receptor complexes, a highly dynamic...

  16. Sick leave for follow-up control in thyroid cancer patients: comparison between stimulation with Thyrogen and thyroid hormone withdrawal.

    Science.gov (United States)

    Borget, I; Corone, C; Nocaudie, M; Allyn, M; Iacobelli, S; Schlumberger, M; De Pouvourville, G

    2007-05-01

    The clinical benefits of recombinant human thyroid-stimulating hormone (rhTSH; Thyrogen) are well established as an alternative stimulation procedure to thyroid hormone withdrawal in the diagnostic follow-up of thyroid cancer patients. By avoiding periods of hypothyroidism, patients do not suffer from a decreased quality of life and keep their ability to work. This study compared the frequency, the duration and the cost of sick leave for follow-up control between rhTSH and withdrawal. The study population consisted of patients with thyroid carcinoma first treated by thyroidectomy and radioiodine ablation. Patients were recruited at their control visit between October 2004 and May 2006 in three hospitals, both prospectively and retrospectively. Collection data consisted of patient information, job characteristics and duration of sick leave during the month before and the month after control. The valuation of sick leave used the friction cost method. Among the 306 patients included, 292 (95%) completed the entire questionnaire. The mean age was 46.7 years. Among the 194 active patients, patients treated with rhTSH, when compared with patients treated by withdrawal, were less likely to require sick leave (11 vs 33%; P=0.001). The mean duration of sick leave was shorter (3.1 vs 11.2 days; P=0.002) and indirect costs due to absenteeism accounted for 454 Euro +/- 1673 vs 1537 Euro +/- 2899 for withdrawal stimulation. For active patients, rhTSH treatment reduced the length and the cost of sick leave by 8.1 days and 1083 Euro per control respectively, when compared with withdrawal treatment.

  17. Effects of graded doses of goitrin, a goitrogen in rapeseed, on synthesis and release of thyroid hormone in chicks

    International Nuclear Information System (INIS)

    Akiba, Yukio; Matsumoto, Tatsuro

    1977-01-01

    Intrathyroidal metabolism in synthesis and release of thyroid hormone was investigated in chicks administered three different levels of goitrin (0.0125, 0.025 and 0.05% in the diet) for 14 days. Thyroid glands were enlarged to 2-5 times as large as that of the control in proportion to the goitrin content of the diet. Typical high radioiodine uptake goiter was demonstrated in the goitrin-administered chicks. Total thyroid 125 I content increased about twice as much as that of the control in the goitrin-administered chicks though it was depressed in 0.0065% PUT-administered chicks. Decrease of plasma PB 125 I (approximately a half of the control) was ascertained by the estimation of plasma thyroxine by radiostereoassay. In the intrathyroidal metabolism of iodine, synthesis of iodothyronines and iodination of MIT were suppressed by goitrin, but monoiodination of tyrosine was rather accelerated. The elevated ratio of thyroid iodothyronines/plasma PBI (1.5-1.7 times as much as that of the control) reveals that the depression of plasma level of thyroid hormone is more striking than the decrease in thyroid hormone in the gland in the goitrin-administered chicks. It is, therefore, suggested that goitrin has inhibitory effects not only on the biosynthesis of thyroid hormone in the gland but also on the release of thyroid hormone from the gland. (auth.)

  18. Do thyroid hormones mediate the effects of starvation on mood in adolescent girls with eating disorders?

    Science.gov (United States)

    Swenne, Ingemar; Rosling, Agneta

    2010-11-01

    In the eating disorders (ED) comorbid depression is common and clinical experience suggests that it is partly related to starvation. Starvation affects thyroid hormone status and thyroid hypofunction is in turn associated with depressed mood. We have therefore investigated the possibility that thyroid hormones and starvation are associated with mood in ED. Two-hundred and thirty-nine adolescent girls were examined at presentation of an ED. Analyses of thyroid hormones, documentation of weight and weight changes, self-reports of depressive symptomatology and clinical diagnoses of ED and depression were used in the analyses. Of the 239 girls 100 were diagnosed with depression. The girls with and without depression did not differ in age, weight, height, body mass index (BMI), weight loss or duration of disease. Plasma free thyroxine concentrations were lower in depressed girls (11.9±1.7 versus 12.8±1.9 pmol/L; pdepression. Low circulating thyroxine concentrations may provide a link between starvation and depression in adolescent girls with ED. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Thyroid hormones and mortality risk in euthyroid individuals: the Kangbuk Samsung health study.

    Science.gov (United States)

    Zhang, Yiyi; Chang, Yoosoo; Ryu, Seungho; Cho, Juhee; Lee, Won-Young; Rhee, Eun-Jung; Kwon, Min-Jung; Pastor-Barriuso, Roberto; Rampal, Sanjay; Han, Won Kon; Shin, Hocheol; Guallar, Eliseo

    2014-07-01

    Hyperthyroidism and hypothyroidism, both overt and subclinical, are associated with all-cause and cardiovascular mortality. The association between thyroid hormones and mortality in euthyroid individuals, however, is unclear. To examine the prospective association between thyroid hormones levels within normal ranges and mortality endpoints. A prospective cohort study of 212 456 middle-aged South Korean men and women who had normal thyroid hormone levels and no history of thyroid disease at baseline from January 1, 2002 to December 31, 2009. Free T4 (FT4), free T3 (FT3), and TSH levels were measured by RIA. Vital status and cause of death ascertainment were based on linkage to the National Death Index death certificate records. After a median follow-up of 4.3 years, 730 participants died (335 deaths from cancer and 112 cardiovascular-related deaths). FT4 was inversely associated with all-cause mortality (HR = 0.77, 95% confidence interval 0.63-0.95, comparing the highest vs lowest quartile of FT4; P for linear trend = .01), and FT3 was inversely associated cancer mortality (HR = 0.62, 95% confidence interval 0.45-0.85; P for linear trend = .001). TSH was not associated with mortality endpoints. In a large cohort of euthyroid men and women, FT4 and FT3 levels within the normal range were inversely associated with the risk of all-cause mortality and cancer mortality, particularly liver cancer mortality.

  20. Effect of laser treatment on thyroid gland hormones in female rabbits

    Directory of Open Access Journals (Sweden)

    N. S. AL-Mustawfi

    2011-01-01

    Full Text Available This study was designed to investigate the effect of laser treatment on thyroid functions and hormones in female rabbits. A total of 18 female rabbits were used in this investigation. Six rabbits were used for examining the thyroid gland location and dissected to be sure that laser therapy will be directed to this gland. Twelve female rabbits were used in this experiment to study the physiological effect of laser therapy (4J/cm2 on normal thyroid function they were divided into two equal groups, six used as control and the others were exposed to laser therapy at the thyroid gland region for three successive days for 5 minutes on each side. Then blood was collected for hormonal assay from ear vein at 1, 6, 12, 18, 24 and 30 days after the last dose of laser treatment. The results revealed a gradual decrease in serum T3 and T4 levels with a concomitant increase in TSH level at the first eighteen days of laser treatment, then normalization of hormones level were take place to be normal after thirty days. More work is needed on this subject to examine the specific role of laser on glands.

  1. D2-Thr92Ala, thyroid hormone levels and biochemical hypothyroidism in preeclampsia.

    Science.gov (United States)

    Procopciuc, Lucia Maria; Caracostea, Gabriela; Hazi, Georgeta; Nemeti, Georgiana; Stamatian, Florin

    2017-02-01

    To identify if there is a relationship between the deiodinase D2-Thr92Ala genetic variant, thyroid hormone levels and biochemical hypothyroidism in preeclampsia. We genotyped 125 women with preeclampsia and 131 normal pregnant women using PCR-RFLP. Serum thyroid hormone levels were determined using ELISA. Our study showed higher TSH and FT4 levels and lower FT3 levels in women with preeclampsia compared to normal pregnant women, with statistical significance for women with mild and severe preeclampsia. The risk to develop pregnancy-induced hypertension (PIH), mild or severe preeclampsia was increased in carriers of at least one D2-Ala92 allele. TSH and FT4 levels were significantly higher and FT3 levels were significantly lower in preeclamptic women with severe preeclampsia if they carried the D2-Ala92 allele compared to non-carriers. Pregnant women with PIH and mild preeclampsia, carriers of at least one D2-Ala92 allele, delivered at lower gestational age neonates with a lower birth weight compared to non-carriers, but the results were statistically significant only in severe preeclampsia. The D2-Thr92Ala genetic variant is associated with the severity and the obstetric outcome of preeclampsia, and it also influences thyroid hormone levels. The study demonstrates non-thyroidal biochemical hypothyroidism - as a result of deiodination effects due to D2 genotypes.

  2. Inappropriate heat dissipation ignites brown fat thermogenesis in mice with a mutant thyroid hormone receptor α1.

    Science.gov (United States)

    Warner, Amy; Rahman, Awahan; Solsjö, Peter; Gottschling, Kristina; Davis, Benjamin; Vennström, Björn; Arner, Anders; Mittag, Jens

    2013-10-01

    Thyroid hormone is a major regulator of thermogenesis, acting both in peripheral organs and on central autonomic pathways. Mice heterozygous for a point mutation in thyroid hormone receptor α1 display increased thermogenesis as a consequence of high sympathetic brown fat stimulation. Surprisingly, despite the hypermetabolism, their body temperature is not elevated. Here we show, using isolated tail arteries, that defective thyroid hormone receptor α1 signaling impairs acetylcholine-mediated vascular relaxation as well as phenylephrine-induced vasoconstriction. Using infrared thermography on conscious animals, we demonstrate that these defects severely interfere with appropriate peripheral heat conservation and dissipation, which in turn leads to compensatory alterations in brown fat activity. Consequently, when the vasoconstrictive defect in mice heterozygous for a point mutation in thyroid hormone receptor α1 was reversed with the selective α1-adrenergic agonist midodrine, the inappropriate heat loss over their tail surface was reduced, normalizing brown fat activity and energy expenditure. Our analyses demonstrate that thyroid hormone plays a key role in vascular heat conservation and dissipation processes, adding a unique aspect to its well-documented functions in thermoregulation. The data thus facilitate understanding of temperature hypersensitivity in patients with thyroid disorders. Moreover, the previously unrecognized connection between cardiovascular regulation and metabolic activity revealed in this study challenges the interpretation of several experimental paradigms and questions some of the currently derived hypotheses on the role of thyroid hormone in thermogenesis.

  3. Inappropriate heat dissipation ignites brown fat thermogenesis in mice with a mutant thyroid hormone receptor α1

    Science.gov (United States)

    Warner, Amy; Rahman, Awahan; Solsjö, Peter; Gottschling, Kristina; Davis, Benjamin; Vennström, Björn; Arner, Anders; Mittag, Jens

    2013-01-01

    Thyroid hormone is a major regulator of thermogenesis, acting both in peripheral organs and on central autonomic pathways. Mice heterozygous for a point mutation in thyroid hormone receptor α1 display increased thermogenesis as a consequence of high sympathetic brown fat stimulation. Surprisingly, despite the hypermetabolism, their body temperature is not elevated. Here we show, using isolated tail arteries, that defective thyroid hormone receptor α1 signaling impairs acetylcholine-mediated vascular relaxation as well as phenylephrine-induced vasoconstriction. Using infrared thermography on conscious animals, we demonstrate that these defects severely interfere with appropriate peripheral heat conservation and dissipation, which in turn leads to compensatory alterations in brown fat activity. Consequently, when the vasoconstrictive defect in mice heterozygous for a point mutation in thyroid hormone receptor α1 was reversed with the selective α1-adrenergic agonist midodrine, the inappropriate heat loss over their tail surface was reduced, normalizing brown fat activity and energy expenditure. Our analyses demonstrate that thyroid hormone plays a key role in vascular heat conservation and dissipation processes, adding a unique aspect to its well-documented functions in thermoregulation. The data thus facilitate understanding of temperature hypersensitivity in patients with thyroid disorders. Moreover, the previously unrecognized connection between cardiovascular regulation and metabolic activity revealed in this study challenges the interpretation of several experimental paradigms and questions some of the currently derived hypotheses on the role of thyroid hormone in thermogenesis. PMID:24046370

  4. The Relationship between Aggression and Serum Thyroid Hormone Level in Individuals Diagnosed with Antisocial Personality Disorder.

    Science.gov (United States)

    Evrensel, Alper; Ünsalver, Barış Önen; Özşahin, Aytekin

    2016-06-01

    Aggression is one of the leading clinical characteristics of antisocial personality disorder (APD). Studies aiming to clarify and control the biological basis of aggression are ongoing. Thyroid hormones have been indicated to play a role in the development of aggression. The aim of this study was to examine the level of aggression and serum thyroid hormone in a sample of APD and to make contributions to this field with the current findings. The sample consisted of 96 subjects with a diagnosis of APD and 97 subjects as a control group. Structured Clinical Interview for DSM-IV Axis (SCID) 1 and 2 were used for the diagnosis, and the Buss-Perry Aggression Questionnaire was administered. Based on criminal patterns, the APD group was then divided into two subgroups: "criminal" and "noncriminal" APD groups. The day after the interview, after one night of fasting, blood was collected from the subjects between 7:00 a.m. and 9:00 a.m.. Thyroid function tests and other biochemical analyses related to the confounding variables were also administered. The study group and the control group were compared in terms of their aggression scores and thyroid hormone levels. The mean score of free T3 level in the criminal APD group was found to be significantly higher than that in the noncriminal APD group. APD subjects with higher free T3 levels also had higher aggression scores. In the noncriminal APD group, as serum free T3 and T4 levels increased, there was also an increment in the aggression scores. However, in the criminal APD group, there was no significant correlation between thyroid hormone levels and aggression. The findings of this study indicated that criminal and noncriminal APD groups actually show different properties.

  5. Associations between brominated flame retardants in human milk and thyroid-stimulating hormone (TSH) in neonates.

    Science.gov (United States)

    Eggesbø, Merete; Thomsen, Cathrine; Jørgensen, Jens V; Becher, Georg; Odland, Jon Øyvind; Longnecker, Matthew P

    2011-08-01

    Brominated flame retardants (BFRs) have been in widespread use in a vast array of consumer products since the 1970s. The metabolites of some BFRs show a structural similarity to thyroid hormones and experimental animal studies have confirmed that they may interfere with thyroid hormone homeostasis. A major concern has been whether intrauterine exposure to BFRs may disturb thyroid homeostasis since the fetal brain is particularly susceptible to alterations in thyroid hormones. However, few reports on newborns have been published to date. To evaluate the association between BFRs and neonatal thyroid-stimulating hormone (TSH). We studied six polybrominated diphenyl ethers (PBDEs) measured in milk samples from 239 women who were part of the "Norwegian Human Milk Study" (HUMIS), 2003-2006. Hexabromocyclododecane (HBCD) and BDE-209 were measured in a subset of the women (193 and 46 milk samples, respectively). The milk was sampled at a median of 33 days after delivery. TSH was measured in babies three days after delivery as part of the routine national screening program for early detection of congenital hypothyroidism. Additional information was obtained through the Medical Birth Registry and questionnaires to the mothers. The PBDE concentrations in human milk in Norway were comparable to concentrations reported from other European countries and Asia, but not the US and Canada where levels are approximately one order of higher magnitude. We observed no statistically significant associations between BDE-47, 99, 153, 154, 209 and HBCD in human milk and TSH in models adjusted for possible confounders and other environmental toxicants including polychlorinated biphenyls (PCBs). We did not observe an association between TSH and exposure to HBCD and PBDEs within the exposure levels observed. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. New avenues for regulation of lipid metabolism by thyroid hormones and analogs

    OpenAIRE

    Senese, Rosalba; Lasala, Pasquale; Leanza, Cristina; de Lange, Pieter

    2014-01-01

    Weight loss due to negative energy balance is a goal in counteracting obesity and type 2 diabetes mellitus. The thyroid is known to be an important regulator of energy metabolism through the action of thyroid hormones (THs). The classic, active TH, 3,5,3’-triiodo-L-thyronine (T3) acts predominantly by binding to nuclear receptors termed TH receptors (TRs), that recognize TH response elements (TREs) on the DNA, and so regulate transcription. T3 also acts through non-genomic pathways that do no...

  7. Thyroid Hormones and Antioxidant Systems: Focus on Oxidative Stress in Cardiovascular and Pulmonary Diseases

    OpenAIRE

    Mancini, Antonio; Raimondo, Sebastiano; Di Segni, Chantal; Persano, Mariasara; Gadotti, Giovanni; Silvestrini, Andrea; Festa, Roberto; Tiano, Luca; Pontecorvi, Alfredo; Meucci, Elisabetta

    2013-01-01

    In previous works we demonstrated an inverse correlation between plasma Coenzyme Q10 (CoQ10) and thyroid hormones; in fact, CoQ10 levels in hyperthyroid patients were found among the lowest detected in human diseases. On the contrary, CoQ10 is elevated in hypothyroid subjects, also in subclinical conditions, suggesting the usefulness of this index in assessing metabolic status in thyroid disorders. A Low-T3 syndrome is a condition observed in several chronic diseases: it is considered an adap...

  8. Growth hormone deficiency in 18q deletion syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Ghidoni, P.D.; Cody, J.; Danney, J. [Univ. of Texas Health Science Center, San Antonio, TX (United States)] [and others

    1994-09-01

    The 18q- syndrome is one of the most common chromosomal deletion syndromes. Clinical characteristics are variable but may include: hypotonia, cleft palate, mental retardation and hearing impairment. Growth failure (GF) (<3% weight/height) is present in 80% of affected individuals. We evaluated growth hormone (GH) sufficiency in 15 patients with 18q- syndrome. Of these 15 patients, 10 have growth failure (<3% weight/height); of the remaining 5, 3 had normal growth parameters and 2 had growth along the 5%. Twelve patients failed to produce adequate GH following standard stimulation testing. Of these 12 patients with inadequate GH production, 2 had normal growth (above 3%). Of the 15, only 1 has normal GH production and normal growth parameters. Bone age was obtained on 1 patient with both GH deficiency and GF, and revealed significant delays. GH levels in response to GH releasing factor were normal in 3 out of 4 patients. MRI studies of GH-deficient patients indicated normal midline structures. Myelination in the few studied GH-deficient patients appeared delayed. The gene for myelin basic protein (MBP) is known to be located on the terminal portion of the long arm of chromosome 18. Neither the gene for GH, GH releasing factor nor GH releasing factor receptor is on chromosome 18. These genes are located on chromosomes 17, chromosome 20 and chromosome 7, respectively. Findings to date suggest that GH deficiency is common in individuals with 18q- syndrome. The etiology of this finding is unknown. We postulate that a gene(s) on chromosome 18q is involved in GH expression.

  9. Studies on the relationship between thyroid hormones, ovarian hormones, GnRH and reproductive performance of egyptian buffaloes

    International Nuclear Information System (INIS)

    Farghaly, H.A.M.

    1992-01-01

    this study was carried out in the experimental farm of animal production department, faculty of agriculture, cairo university. hormonal analysis were performed in the laboratories of animal physiology unit, radiobiology department, nuclear research center, atomic energy authority (radiobiol. Dept., NRC, AEA). The aim of the study was to investigate the following : 1- post-partum reproductive activity of egyptian buffaloes and the factors affecting the resumption of ovarian activity after calving , with particular reference to the patterns of thyroid hormones (T 4 and T 3 ) and progesterone hormone.2- the effectiveness of using GnRH treatment on inducing ovarian activity after calving. 3- the effect of goitrogen administration (thiouracil) on ovarian activity during post-partum and on the response of buffaloes to GnRH treatment and their reproductive patterns

  10. Bone Marrow-Derived Stem Cell Populations Are Differentially Regulated by Thyroid or/and Ovarian Hormone Loss

    Directory of Open Access Journals (Sweden)

    Bassam F. Mogharbel

    2017-10-01

    Full Text Available Bone marrow-derived stem cells (BMDSCs play an essential role in organ repair and regeneration. The molecular mechanisms by which hormones control BMDSCs proliferation and differentiation are unclear. Our aim in this study was to investigate how a lack of ovarian or/and thyroid hormones affects stem cell number in bone marrow lineage. To examine the effect of thyroid or/and ovarian hormones on the proliferative activity of BMDSCs, we removed the thyroid or/and the ovaries of adult female rats. An absence of ovarian and thyroid hormones was confirmed by Pap staining and Thyroid Stimulating Hormone (TSH measurement, respectively. To obtain the stem cells from the bone marrow, we punctured the iliac crest, and aspirated and isolated cells by using a density gradient. Specific markers were used by cytometry to identify the different BMDSCs types: endothelial progenitor cells (EPCs, precursor B cells/pro-B cells, and mesenchymal stem cells (MSCs. Interestingly, our results showed that hypothyroidism caused a significant increase in the percentage of EPCs, whereas a lack of ovarian hormones significantly increased the precursor B cells/pro-B cells. Moreover, the removal of both glands led to increased MSCs. In conclusion, both ovarian and thyroid hormones appear to have key and diverse roles in regulating the proliferation of cells populations of the bone marrow.

  11. The effect of long-term thyroid-stimulating hormone suppressive therapy on the gonadal steroid hormones of patients with thyroid carcinoma after surgery.

    Science.gov (United States)

    Liu, Xiaoli; Zhou, Ying; Liang, Nan; Hong, Yang; Dionigi, Gianlorenzo; Sun, Hui

    2017-10-01

    To analyze the effect of long-term thyroid-stimulating hormone (TSH) suppressive therapy on the gonadal hormones and related symptoms in patients after surgery. From 2008 to 2011, totally 238 patients were recruited, who underwent thyroid surgery and subsequent TSH suppression treatment in Department of thyroid Surgery, China-Japan Union hospital, Jilin University. Then their postoperative follow-up data (3-8 years) were collected, including operational method, pathological diagnosis, whether processed radioiodine therapy and the period/dose of TSH suppression treatment. In addition, the menstrual cycle, menstruation quantity, whether accompanied with dysmenorrheal and menstrual disorder or not, date of last menstrual period, ages of menopause and so on were also collected. (I) Neither the level nor the duration of TSH treatment had any function on estradiol (E2) and testosterone (T) in male patients; (II) in the subgroup of patients with TSH treatment for 3-5 years, patients who took high dose of TSH (TSH ≥0.5 U/L) obtained the lower T level compared with the group of medium dose (1.08±0.34 vs. 1.36±0.46 nmol/L, P=0.001); (III) in the medium dose (0.1 IU/L ≤ TSH hormone (FSH) did not show any change in terms of the dose and the duration of TSH treatment; (V) the menstrual volume, dysmenorrhea condition, menstrual cycle and menopause related indicators did not show any difference in terms of doses and duration of TSH treatment (P=0.701, 0.412 and 0.507 respectively). The long term of TSH repressive therapy after surgery did not affect T and E2 level in male patients. As for female patients, the impact was mainly reflected in the T and E2 levels especially in female sexual maturity but not FSH level. In addition, TSH treatment did not play any role on menstruation or menopause.

  12. The heterochronic gene Lin28 regulates amphibian metamorphosis through disturbance of thyroid hormone function.

    Science.gov (United States)

    Faunes, Fernando; Gundermann, Daniel G; Muñoz, Rosana; Bruno, Renzo; Larraín, Juan

    2017-05-15

    Metamorphosis is a classic example of developmental transition, which involves important morphological and physiological changes that prepare the organism for the adult life. It has been very well established that amphibian metamorphosis is mainly controlled by Thyroid Hormone (TH). Here, we show that the heterochronic gene Lin28 is downregulated during Xenopus laevis metamorphosis. Lin28 overexpression before activation of TH signaling delays metamorphosis and inhibits the expression of TH target genes. The delay in metamorphosis is rescued by incubation with exogenous TH, indicating that Lin28 works upstream or parallel to TH. High-throughput analyses performed before any delay on metamorphosis or change in TH signaling showed that overexpression of Lin28 reduces transcript levels of several hormones secreted by the pituitary, including the Thyroid-Stimulating Hormone (TSH), and regulates the expression of proteins involved in TH transport, metabolism and signaling, showing that Lin28 disrupts TH function at different levels. Our data demonstrates that the role of Lin28 in controlling developmental transitions is evolutionary conserved and establishes a functional interaction between Lin28 and thyroid hormone function introducing a new regulatory step in perinatal development with implications for our understanding of endocrine disorders. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  13. Studies on the regulation of anuran metamorphosis by thyroid hormones and prolactin

    International Nuclear Information System (INIS)

    Ray, L.B.

    1985-01-01

    Resorption of the tail of the anuran larva during metamorphosis is induced by the thyroid hormones. In contrast, the pituitary hormone prolactin favors growth of the tail fin and inhibits resorption. The present investigations were designed to explore the mechanisms by which the thyroid hormones and prolactin bring about their cellular effects. Incubation of explants of tail fin with derivatives of cAMP was shown to inhibit T 4 -induced resorption of explants in a manner similar to that of prolactin. Likewise, inhibition of phosphodiesterases also inhibited resorption. Prolactin, however, failed to alter the levels of cAMP in cultured explants of tail fin. Although cAMP antagonizes the resorptive effects of T 4 , prolactin apparently does not act by elevating cellular levels of that cyclic nucleotide. Newly synthesized proteins from explants of tail fin were examined by isotopical labeling followed by two-dimensional gel electrophoresis and fluorography. Incorporation of 35 S-methionine into four proteins was increased within 8 to 48 hours after exposure of explants to T 4 . Three of the same proteins appeared to be synthesized more rapidly in explants of fin from tadpoles at metamorphic climax than in fin from tadpoles of premetamorphic stages. These results indicate that treatment of explants with T 4 or elevation of endogenous levels of thyroid hormones during spontaneous metamorphosis increased the relative rates of synthesis of several proteins. Those proteins are potentially involved in initiating the effects of T 4 which lead to cell death and resorption of the tail

  14. Thyroid hormone levels in patients with chronic renal failure under haemodialysis

    International Nuclear Information System (INIS)

    Khalid, Ahmed Shukralla M.

    1998-06-01

    This study was conducted with three main objectives, to study thyroid hormones (T 4 , T 3 ) and TSH levels in patients with CRF under haemodialysis and to compare them with normal subjects, to study best means of treatment and to compare these findings with results from other parts of the world. This study was done on 61 patients with renal failure in Khartoum dialysis and kidney transplant centre U of K, 45 males and 16 females with ages ranging from 17-75 years and 42 symptoms-free subjects 14 males and 23 females with age ranging from 16-60 years. The radioimmunoassay (RIA) technique was used for the determination of serum T 4 , T 3 and TSH. By using t-test found that the mean concentrations of T 4 , T 3 of normal subjects were much higher than those of the patients (p 0.05). These results also illustrated that 45.9% of patients with renal failure of low T 4 , and 91.8%, 90.26 of patients had T 3 and TSH hormone levels in the normal range, respectively. No significant difference was observed in the mean of thyroid hormones (T 4 , T 3 ) and thyroid-stimulating hormones between males and females (p>0.05). The T 3 and T '4 concentrations in patients at all age groups (year) was less than the age groups of the control group, and this decrease was statistically significant (p 0.05).(Author)

  15. Postnatal thyroid hormone supplementation rescues developmental abnormalities induced by congenital-neonatal hypothyroidism in the rat retina.

    Science.gov (United States)

    Pinazo-Durán, Maria Dolores; Iborra, Francisco J; Pons, Sheila; Sevilla-Romero, Enrique; Gallego-Pinazo, Roberto; Muñoz, Alberto

    2005-01-01

    Thyroid hormones (TH) play a key role in central nervous system development. We have studied the influence of congenital and neonatal hypothyroidism on retinal development and the effects of postnatal TH supplementation. An experimental model was set up using Wistar rats by inducing chemical thyroidectomy during gestation and suckling. Eyes from control (CG) and TH-depleted (THDG) groups of animals were obtained at postnatal days 10 and 25. In the THDG, there was a significant reduction in the retinal thickness and layering, retinal volume, cell number and nuclear volumes in all layers. A third group of rats, made hypothyroid during the gestational and neonatal period and then supplemented with TH (THSG), showed a recovery of both the retinal thickness [at P25: 188.5 +/- 9.2 microm (THSG) vs. 175.8 +/- 16.1 microm (THDG), p < 0.001, and 210.8 +/- 8.9 (CG)] and total retinal cell number [at P25: 6.9 x 10(6) (THSG) vs. 3.7 x 10(6) (THDG) cells, p < 0.001, and 5.3 x 10(6) cells (CG)]. Light and electron microscopy studies confirmed that TH deprivation altered the organization of the retina, which was mostly normalized by hormone administration. Our data show that TH regulates intrinsic mechanisms for controlling retinal cytoarchitecture and layering, and that alterations in retinal maturation induced by congenital-neonatal TH deficiency can be at least partially rescued by early hormonal treatment in vivo.

  16. Amiodarone-induced thyroid dysfunction.

    Science.gov (United States)

    Danzi, Sara; Klein, Irwin

    2015-05-01

    Amiodarone is an effective medication for the treatment of cardiac arrhythmias. Originally developed for the treatment of angina, it is now the most frequently prescribed antiarrhythmia drug despite the fact that its use is limited because of potential serious side effects including adverse effects on the thyroid gland and thyroid hormones. Although the mechanisms of action of amiodarone on the thyroid gland and thyroid hormone metabolism are poorly understood, the structural similarity of amiodarone to thyroid hormones, including the presence of iodine moieties on the inner benzene ring, may play a role in causing thyroid dysfunction. Amiodarone-induced thyroid dysfunction includes amiodarone-induced thyrotoxicosis (AIT) and amiodarone-induced hypothyroidism (AIH). The AIT develops more commonly in iodine-deficient areas and AIH in iodine-sufficient areas. The AIT type 1 usually occurs in patients with known or previously undiagnosed thyroid dysfunction or goiter. The AIT type 2 usually occurs in normal thyroid glands and results in destruction of thyroid tissue caused by thyroiditis. This is the result of an intrinsic drug effect from the amiodarone itself. Mixed types are not uncommon. Patients with cardiac disease receiving amiodarone treatment should be monitored for signs of thyroid dysfunction, which often manifest as a reappearance of the underlying cardiac disease state. When monitoring patients, initial tests should include the full battery of thyroid function tests, thyroid-stimulating hormone, thyroxine, triiodothyronine, and antithyroid antibodies. Mixed types of AIT can be challenging both to diagnose and treat and therapy differs depending on the type of AIT. Treatment can include thionamides and/or glucocorticoids. The AIH responds favorably to thyroid hormone replacement therapy. Amiodarone is lipophilic and has a long half-life in the body. Therefore, stopping the amiodarone therapy usually has little short-term benefit. © The Author(s) 2013.

  17. Growth hormone (GH-1) gene deletions in children with isolated growth hormone deficiency (IGHD).

    Science.gov (United States)

    Desai, Meena P; Mithbawkar, Shilpa M; Upadhye, Pradnya S; Shalia, Kavita K

    2012-07-01

    To detect growth hormone GH-1 gene deletions (6.7 kb, 7.6 kb, 7 kb) in familial/nonfamilial isolated growth hormone deficiency (IGHD) and note their clinical and investigative profile. Thirty (M16,F14) prepubertal IGHD patients aged 0.25 to 14 y, from 25 families were screened. Duration of growth failure, relevant history, clinical phenotype, and height SDS were recorded. Peak GH response to Clonidine (0.15 mg/m(2)), IGF-1, IGFBP-3 and pituitary/target gland hormones were studied. Genomic DNA of patients and family was analysed by PCR and DNA fragments were visualized on agarose gel electrophoresis. This series was divided into deletion +ve, Group I (n=12,40%) inclusive of six familial/six nonfamilial patients, and deletion -ve Group II (n=18,60%), 5 familial/13 nonfamilial cases; in total 11/30 were familial. Onset of growth failure was earlier in Group I (pGH hormones were normal and MRI showed hypoplastic adenohypophysis. 40% had GH-1 gene deletion (6.7 kb deletion in 83%, 7.6 kb and a compound heterozygote in 8% each). In this series of 30 IGHD patients, frequency of GH-1 gene deletions (12/30) was 40%, and 54% among familial patients, and 31% with height SDS>-4. 83% had 6.7 kb deletion. Height SDS>-4, clinical phenotype, peak GH<1 ng/ml and hypoglycemia characterised IGHD Type IA.

  18. Structural Abnormalities and Learning Impairments Induced by Low Level Thyroid Hormone Insufficiency: A Cross-Fostering Study

    Science.gov (United States)

    Severe reductions in thyroid hormones (TH) during development alter brain structure and impair learning. Uncertainty surrounds both the impact oflower levels of TH disruption and the sensitivity of available metrics to detect neurodevelopmental deficits of this disruption. We ha...

  19. A structural abnormality associated with graded levels of thyroid hormone insufficiency: Dose dependent increases in heterotopia volume

    Science.gov (United States)

    A large number of environmental contaminants reduce circulating levels of thyroid hormone (TH), but clear markers of neurological insult associated with modest TH insufficiency are lacking. We have previously identified the presence of an abnormal cluster of misplaced neurons in ...

  20. Thyroid Hormone Disruption Effects Lamination of the Neocortex but not the Cerebellum in a Model of Developmental Hypothyroidism and Hypothyroxinemia

    Science.gov (United States)

    Introduction: Research on neurodevelopmental changes resulting from thyroid hormone (TH) disruption has important basic and clinical implications. We previously demonstrated, in a rodent model, that developmental hypothyroidism or hypothyroxinemia can cause ...

  1. Spatial and temporal expression of glucocorticoid, retinoid, and thyroid hormone receptors is not altered in lungs of congenital diaphragmatic hernia

    NARCIS (Netherlands)

    Rajatapiti, Prapapan; Keijzer, Richard; Blommaart, Pietjan E.; Lamers, Wouter H.; de Krijger, Ronald R.; Visser, Theo J.; Tibboel, Dick; Rottier, Robbert

    2006-01-01

    The degree of associated pulmonary hypoplasia and persistent pulmonary hypertension are major determination factors for survival in congenital diaphragmatic hernia (CDH) patients. Glucocorticoids, thyroid hormone, and vitamin A have been shown to be involved in human lung development. To determine

  2. Thyroid hormone binding proteins as novel targets for hydroxylated polyhalogenated aromatic hydrocarbons (PHAHs) : possible implications for toxicity

    NARCIS (Netherlands)

    Lans, M.C.

    1995-01-01

    Some toxic effects caused by polyhalogenated aromatic hydrocarbons (PHAHs) develop through alterations in the reproductive and thyroid hormone regulatory systems, thereby affecting (brain) development, reproduction and behaviour of several species (Stone, 1995, Birnbaum, 1994, for review:

  3. Effect of growth hormone-releasing factor on growth hormone release in children with radiation-induced growth hormone deficiency

    International Nuclear Information System (INIS)

    Lustig, R.H.; Schriock, E.A.; Kaplan, S.L.; Grumbach, M.M.

    1985-01-01

    Five male children who received cranial irradiation for extrahypothalamic intracranial neoplasms or leukemia and subsequently developed severe growth hormone (GH) deficiency were challenged with synthetic growth hormone-releasing factor (GRF-44), in an attempt to distinguish hypothalamic from pituitary dysfunction as a cause of their GH deficiency, and to assess the readily releasable GH reserve in the pituitary. In response to a pulse of GRF-44 (5 micrograms/kg intravenously), mean peak GH levels rose to values higher than those evoked by the pharmacologic agents L-dopa or arginine (6.4 +/- 1.3 ng/mL v 1.5 +/- 0.4 ng/mL, P less than .05). The peak GH value occurred at a mean of 26.0 minutes after administration of GRF-44. These responses were similar to those obtained in children with severe GH deficiency due to other etiologies (peak GH 6.3 +/- 1.7 ng/mL, mean 28.0 minutes). In addition, there was a trend toward an inverse relationship between peak GH response to GRF-44 and the postirradiation interval. Prolactin and somatomedin-C levels did not change significantly after the administration of a single dose of GRF-44. The results of this study support the hypothesis that cranial irradiation in children can lead to hypothalamic GRF deficiency secondary to radiation injury of hypothalamic GRF-secreting neurons. This study also lends support to the potential therapeutic usefulness of GRF-44 or an analog for GH deficiency secondary to cranial irradiation

  4. Two missense mutations in KCNQ1 cause pituitary hormone deficiency and maternally inherited gingival fibromatosis

    DEFF Research Database (Denmark)

    Tommiska, Johanna; Känsäkoski, Johanna; Skibsbye, Lasse

    2017-01-01

    Familial growth hormone deficiency provides an opportunity to identify new genetic causes of short stature. Here we combine linkage analysis with whole-genome resequencing in patients with growth hormone deficiency and maternally inherited gingival fibromatosis. We report that patients from three...... associated with maternally inherited gingival fibromatosis is an allelic disorder with cardiac arrhythmia syndromes caused by KCNQ1 mutations....

  5. Timing of growth hormone treatment affects trabecular bone microarchitecture and mineralization in growth hormone deficient mice.

    Science.gov (United States)

    Kristensen, Erika; Hallgrímsson, Benedikt; Morck, Douglas W; Boyd, Steven K

    2010-08-01

    Growth hormone (GH) is essential in the development of bone mass, and a growth hormone deficiency (GHD) in childhood is frequently treated with daily injections of GH. It is not clear what effect GHD and its treatment has on bone. It was hypothesized that GHD would result in impaired microarchitecture, and an early onset of treatment would result in a better recovery than late onset. Growth hormone deficient homozygous (lit/lit) mice of both sexes were divided into two treatment groups receiving daily injections of GH, starting at an early (21 days of age) or a late time point (35 days of age, corresponding to the end of puberty). A group of heterozygous mice with normal levels of growth hormone served as controls. In vivo micro-computed tomography scans of the fourth lumbar vertebra were obtained at five time points between 21 and 60 days of age, and trabecular morphology and volumetric BMD were analyzed to determine the effects of GH on bone microarchitecture. Early GH treatment led to significant improvements in bone volume ratio (p=0.006), tissue mineral density (p=0.005), and structure model index (p=0.004) by the study endpoint (day 60), with no detected change in trabecular thickness. Trabecular number increased and trabecular separation decreased in GHD mice regardless of treatment compared to heterozygous mice. This suggests fundamental differences in the structure of trabecular bone in GHD and GH treated mice, reflected by an increased number of thinner trabeculae in these mice compared to heterozygous controls. There were no significant differences between the late treatment group and GHD mice except for connectivity density. Taken together, these results indicate that bone responds to GH treatment initiated before puberty but not to treatment commencing post-puberty, and that GH treatment does not rescue the structure of trabecular bone to that of heterozygous controls. Copyright 2010 Elsevier Inc. All rights reserved.

  6. Association of Vitamin D Deficiency and Thyroid Function in Postmenopausal Women

    Directory of Open Access Journals (Sweden)

    Mitra Niafar

    2016-12-01

    Full Text Available Pupose: Although there are reports of vitamin D (VitD insufficiency in immune-mediated hypothyroidism, an association between VitD and thyroid-stimulating hormone (TSH levels has yet to be shown. We aim to examine VitD and TSH levels among postmenopausal women, as both conditions are more prevalent in elderly women. Methods: The clinic records of postmenopausal women during their routine maintenance visits were reviewed. All patients were examined for the symptoms related to thyroid function and osteoporosis. Participants were divided into three subgroups according to their TSH levels (below 4.0 mIU/L. Patient characteristics and VitD levels were compared between these subgroups. Multivariate linear regression model was constructed using serum VitD and serum TSH as the dependent variables to identify factors independently associated with these laboratory values. Results: Two-hundred and nighty nine postmenopausal women were included. Average age was 62.2±7.5 years old. VitD was insufficient (10-30 ng/mL in 12.0% and deficient (<10 ng/mL in 60.9% of the participants. In 11.3%, TSH was low and in 7.6% of women, TSH was high, while the remaining 80.1%, had normal TSH levels. Subjects with low TSH had significantly higher VitD concentrations (34.2±29.1 ng/mL compared to the other two groups (P-value: 0.039. In multivariate regression analysis, TSH was not a contributing factor, as age was the only significant predictor of VitD levels. Meanwhile, no predictor (including age and VitD was identified for TSH levels in linear regression analysis. Conclusion: Age was the only independent predictor of serum VitD in this study population. Though suppressed TSH was associated with higher VitD levels, the association was not linear between TSH and VitD in postmenopausal women.

  7. Thyroid Hormone Receptors Control Developmental Maturation of the Middle Ear and the Size of the Ossicular Bones

    OpenAIRE

    Cordas, Emily A.; Ng, Lily; Hernandez, Arturo; Kaneshige, Masahiro; Cheng, Sheue-Yann; Forrest, Douglas

    2012-01-01

    Thyroid hormone is critical for auditory development and has well-known actions in the inner ear. However, less is known of thyroid hormone functions in the middle ear, which contains the ossicles (malleus, incus, stapes) that relay mechanical sound vibrations from the outer ear to the inner ear. During the later stages of middle ear development, prior to the onset of hearing, middle ear cavitation occurs, involving clearance of mesenchyme from the middle ear cavity while the immature cartila...

  8. Abnormalities of Thyroid Hormone Metabolism during Systemic Illness: The Low T3 Syndrome in Different Clinical Settings

    OpenAIRE

    Arnaldo Moura Neto; Denise Engelbrecht Zantut-Wittmann

    2016-01-01

    Thyroid hormone abnormalities are common in critically ill patients. For over three decades, a mild form of these abnormalities has been described in patients with several diseases under outpatient care. These alterations in thyroid hormone economy are a part of the nonthyroidal illness and keep an important relationship with prognosis in most cases. The main feature of this syndrome is a fall in free triiodothyronine (T3) levels with normal thyrotropin (TSH). Free thyroxin (T4) and reverse T...

  9. Thyroid Hormone Activates Brown Adipose Tissue and Increases Non-Shivering Thermogenesis--A Cohort Study in a Group of Thyroid Carcinoma Patients.

    Directory of Open Access Journals (Sweden)

    Evie P M Broeders

    Full Text Available Thyroid hormone receptors are present on brown adipose tissue (BAT, indicating a role for thyroid hormone in the regulation of BAT activation. The objective of this study was to examine the effect of thyroid hormone withdrawal followed by thyroid hormone in TSH-suppressive dosages, on energy expenditure and brown adipose tissue activity.This study was a longitudinal study in an academic center, with a follow-up period of 6 months. Ten patients with well-differentiated thyroid carcinoma eligible for surgical treatment and subsequent radioactive iodine ablation therapy were studied in a hypothyroid state after thyroidectomy and in a subclinical hyperthyroid state (TSH-suppression according to treatment protocol. Paired two-tailed t-tests and linear regression analyses were used.Basal metabolic rate (BMR was significantly higher after treatment with synthetic thyroid hormone (levothyroxine than in the hypothyroid state (BMR 3.8 ± 0.5 kJ/min versus 4.4 ± 0.6 kJ/min, P = 0.012, and non-shivering thermogenesis (NST significantly increased from 15 ± 10% to 25 ± 6% (P = 0.009. Mean BAT activity was significantly higher in the subclinical hyperthyroid state than in the hypothyroid state (BAT standard uptake value (SUVMean 4.0 ± 2.9 versus 2.4 ± 1.8, P = 0.039.Our study shows that higher levels of thyroid hormone are associated with a higher level of cold-activated BAT.ClinicalTrials.gov NCT02499471.

  10. Study on the relationship between serum levels of leptin thyroid hormones

    International Nuclear Information System (INIS)

    Lin Pingan; Zhai Chuntao; Yuan Sufen

    2005-01-01

    Objective: To evaluate the relationship between serum levels of leptin and thyroid functional status. Methods: Serum leptin (with RIA) and pituitary-thyroid axis hormones (with CLIA) were measured in 75 euthyroid controls, 44 hyperthyroid subjects and 27 hypothyroid subjects. Results: The levels of leptin in euthyroid controls, hyperthyroid subjects and hypothyroid subjects were (5.40 ± 3.78) ng/ml, (5.99 ± 5.24) ng/ml and (5.59 ± 4.23) ng/ml respectively with no significant differences among them. The serum leptin levels were positively correlated with serum TSH levels (r=0.27, P<0.01). Conclusion: Thyroid function has no effect on serum leptin levels and TSH levels correlates closely with those of serum leptin. (authors)

  11. Photoperiod-dependent negative feedback effects of thyroid hormones in Fundulus heteroclitus

    International Nuclear Information System (INIS)

    Brown, C.L.; Stetson, M.H.

    1985-01-01

    In Fundulus heteroclitus, an annual cycle in the response of the thyroid to ovine thyroid-stimulating hormone (oTSH) is characterized by maximal thyroxin (T4) secretion in mid-winter and minimal T4 secretion in summer. Four daily injections of oTSH, given in winter caused serum T4 to plateau at elevated levels for several days, while in summer fish similar treatment resulted in far more fluctuating titers of serum T4; maximum levels were similar in both groups. The difference in sustenance rather than magnitude of Peak T4 led to an examination of the negative feedback effects of thyroid hormones as they might relate to these seasonal changes. Radioiodine uptake by thyroid follicles served as a simple, but effective bioassay for endogenous TSH. Fish collected in summer were more sensitive to negative feedback of T3 than those collected in winter; feedback effects of T4 in the two groups were not significantly different. The effects of specific photoperiods on negative feedback sensitivity to T3 and T4 were also tested. Exposure of winter fish for one month to long days (LD 14:10) enhanced the degree of reduction of iodine uptake caused by T4 in the aquarium water (10 micrograms/100 ml). Negative feedback in short-day (LD 8:16) winter fish was not demonstrated. It is concluded that long days increase and short days diminish the negative feedback sensitivity of the hypothalamus-pituitary axis to thyroid hormones in F. heteroclitus. Such photoperiodically induced changes may act to aid in the year-round maintenance of T4 levels necessary for seasonal adaptation and survival

  12. Magnetic resonance imaging of cerebral anomalies in subjects with resistance to thyroid hormone

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, C.M. [Univ. of Florida Health Science Center, Gainesville, FL (United States); Hauser, P.; Weintraub, B.D. [National Institute of Mental Health, Bethesda, MD (United States)]|[Baltimore VA Medical Center, MD (United States)] [and others

    1995-06-19

    Resistance to thyroid hormone (RTH) is an autosomal dominant disease caused by mutations in the human thyroid receptor beta gene on chromosome 3. Individuals with RTH have an increased incidence of attention deficit hyperactivity disorder (ADHD). The purpose of this study was to search for developmental brain malformations associated with RTH. Forty-three subjects (20 affected males [AM], 23 affected females [AF]) with resistance to thyroid hormone and 32 unaffected first degree relatives (18 unaffected males [UM], 14 unaffected females [UF]) underwent MRI brain scans with a volumetric acquisition that provided 90 contiguous 2 mm thick sagittal images. Films of six contiguous images beginning at a standard sagittal position lateral to the insula were analyzed by an investigator who was blind with respect to subject characteristics. The presence of extra or missing gyri in the parietal bank of the Sylvian fissure (multimodal association cortex) and multiple Heschl`s transverse gyri (primary auditory cortex) were noted. There was a significantly increased frequency of anomalous Sylvian fissures in the left hemisphere in males with RTH (AM: 70%; AF: 30%; UM: 28% UF: 28%). Also, there was an increased frequency of anomalous Sylvian fissures on the left combined with multiple Heschl`s gyri in either hemisphere in males with RTH (AM: 50%; AF: 9%; UM: 6%; UF: 0%). However, RTH subjects with anomalies did not have an increased frequency of ADHD as compared with RTH subjects with no anomalies. Abnormal thyroid hormone action in the male fetus early during brain development may be associated with grossly observable cerebral anomalies of the left hemisphere. The effects of mutations in the thyroid receptor beta gene provide a model system for studying the complex interaction of genetic and non-genetic factors on brain and behavioral development. 19 refs., 2 figs., 2 tabs.

  13. Effects of PBDE-47 on thyroid and steroid hormone status in juvenile turbot (Schophtalamus maximus)

    Energy Technology Data Exchange (ETDEWEB)

    Jenssen, G.; Tyrhaug, I.B.; Sormo, E.G. [Dept. of Biology, Norwegian Univ. of Science and Technology, Trondheim (Norway); Andersen, O.K. [Rogaland Research Akvamiljo, Mekjarvik (Norway)

    2004-09-15

    Many of the brominated flame retardant (BFR) chemicals, and particularly polybrominated diphenyl ethers (PBDEs), has become of increasing concern to scientists over the past decade. Many of the PBDEs are persistent and lipophilic and have been shown to bioaccumulate. The levels of PBDEs in biota seem to be increasing, and several trends, including in humans, indicate that this increase may be rapid1. In general, BFRs have a low acute toxicity, but there is concern about their long-term toxic effects. Exposure studies have revealed a range of subtle biochemical, cellular and physiological effects following low-dose exposure, and many BFRs have been reported to have endocrine disruptive properties. Thus, there is concern about their potential to affect organisms and populations. Thyroid hormones (THs) play an important role in organism's development, metabolism, growth and behavior. Polyhalogenated aromatic hydrocarbons (PHAHs) including BFRs may affect the thyroid system through several mechanisms. They may directly affect the thyroid gland function, the peripheral metabolism of THs and/or the binding of THs to plasma transport proteins. Effects of PHAHs on TH homeostasis have been documented in a number of species, including fish. Du to its persistence against degradation PBDE-47 is among the most abundant PBDE congener in biota, and there is a great concern about its ecotoxicological effects on organisms and populations. The aim of the present study was to examine if PBDE-47 may affect levels of circulating steroid and thyroid hormones in juvenile turbot (Scophtalamus maximus). The turbot is a benthic living flatfish that can be exposed to PHAHs via the sediment living organisms. Thus, plasma levels of T, E, and the thyroid hormones thyroxine (T4) and triiodothyronine (T3) were determined in juvenile turbot that had been continuously exposed to PBDE-47 via water for 3 weeks.

  14. Bioanalytical and instrumental analysis of thyroid hormone disrupting compounds in water sources along the Yangtze River

    Energy Technology Data Exchange (ETDEWEB)

    Shi Wei [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Wang Xiaoyi [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Jiangsu Academy of Environmental Science, Nanjing 210036 (China); Hu Guanjiu; Hao Yingqun [State Environmental Protection Key Laboratory of Monitoring and Analysis for Organic Pollutants in Surface Water, Jiangsu Provincial Environmental Monitoring Center, Nanjing 210036 (China); Zhang Xiaowei [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Liu Hongling, E-mail: hlliu@nju.edu.c [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Wei Si [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Wang Xinru [Key Laboratory of Reproductive Medicine and Institute of Toxicology, Nanjing Medical University, Nanjing 210029 (China); Yu Hongxia, E-mail: hongxiayu@nju.edu.c [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China)

    2011-02-15

    Thyroid hormone (TH) agonist and antagonist activities of water sources along the Yangtze River in China were surveyed by a green monkey kidney fibroblast (CV-1) cell-based TH reporter gene assay. Instrumental analysis was conducted to identify the responsible thyroid-active compounds. Instrumentally derived L-3,5,3'-triiodothyronine (T{sub 3}) equivalents (T{sub 3}-EQs) and thyroid receptor (TR) antagonist activity equivalents referring to dibutyl phthalate (DBP-EQs) were calculated from the concentrations of individual congeners. The reporter gene assay demonstrated that three out of eleven water sources contained TR agonist activity equivalents (TR-EQs), ranging from 286 to 293 ng T{sub 3}/L. Anti-thyroid hormone activities were found in all water sources with the TR antagonist activity equivalents referring to DBP (Ant-TR-EQs), ranging from 51.5 to 555.3 {mu}g/L. Comparisons of the equivalents from instrumental and biological assays suggested that high concentrations of DBP and di-2-ethylhexyl phthalate (DEHP) were responsible for the observed TR antagonist activities at some locations along the Yangtze River. - Research highlights: First of all, we indicated the instrumentally derived L-3,5,3'-triiodothyronine (T{sub 3}) equivalents (T{sub 3}-EQs) and thyroid receptor (TR) antagonist activity equivalents referring to DBP (DBP-EQs) for the very first time. Secondly, high concentrations of DBP and DEHP might be responsible for the observed TR antagonist activities at some locations. Finally, we found that thyroid receptor (TR) antagonist activities were very common in Yangtze River. More attentions should be paid to the TR antagonist activities and the responsible compounds. - In vitro bioassay responses observed in Yangtze River source water extracts showed great TR antagonist activities, and DBP and DEHP were responsible.

  15. Comparison of cortisol and thyroid hormones between tuberculosis-suspect and healthy elephants of Nepal.

    Science.gov (United States)

    Paudel, Sarad; Brown, Janine L; Thapaliya, Sharada; Dhakal, Ishwari P; Mikota, Susan K; Gairhe, Kamal P; Shimozuru, Michito; Tsubota, Toshio

    2016-12-01

    We compared cortisol and thyroid hormone (T3 and T4) concentrations between tuberculosis (TB)-suspected (n=10) and healthy (n=10) elephants of Nepal. Whole blood was collected from captive elephants throughout Nepal, and TB testing was performed using the ElephantTB STAT-PAK ® and DPP VetTB ® serological assays that detect antibodies against Mycobacterium tuberculosis and M. bovis in elephant serum. Cortisol, T3 and T4 were quantified by competitive enzyme immunoassays, and the results showed no significant differences in hormone concentrations between TB-suspect and healthy elephants. These preliminary data suggest neither adrenal nor thyroid function is altered by TB disease status. However, more elephants, including those positively diagnosed for TB by trunk wash cultures, need to be evaluated over time to confirm results.

  16. Clinical significance of determination of serum thyroid hormones levels in patients with diabetic-2 nephrosis

    International Nuclear Information System (INIS)

    Zhou Feihua; Xu Haifeng; Zhou Runsuo; Sun Tao

    2008-01-01

    Objective: To explore the value of determination of serum thyroid hormones levels in patients with diabetic-2 nephrosis. Methods: Serum thyroid hormones (T 3 , T 4 , rT 3 , sTSH) levels in 98 patients with diabetic-2 nephrosis and 53 controls were measured with RIA. Results: Serum levels of T 3 was significantly higher in patients with diabetic-2 nephrosis than those in controls (P 4 , rT 3 , sTSH levels were not much different (P>0.05). Conclusion: Changes of serum T 3 levels in patients with critical illness were closely related to the severity of the disease process and were useful for outcome prediction. (authors)

  17. Evidence of a bigenomic regulation of mitochondrial gene expression by thyroid hormone during rat brain development

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, Rohit Anthony; Pathak, Amrita; Mohan, Vishwa; Babu, Satish; Pal, Amit; Khare, Drirh [Department of Endocrinology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow 226014 (India); Godbole, Madan M., E-mail: madangodbole@yahoo.co.in [Department of Endocrinology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow 226014 (India)

    2010-07-02

    Hypothyroidism during early mammalian brain development is associated with decreased expression of various mitochondrial encoded genes along with evidence for mitochondrial dysfunction. However, in-spite of the similarities between neurological disorders caused by perinatal hypothyroidism and those caused by various genetic mitochondrial defects we still do not know as to how thyroid hormone (TH) regulates mitochondrial transcription during development and whether this regulation by TH is nuclear mediated or through mitochondrial TH receptors? We here in rat cerebellum show that hypothyroidism causes reduction in expression of nuclear encoded genes controlling mitochondrial biogenesis like PGC-1{alpha}, NRF-1{alpha} and Tfam. Also, we for the first time demonstrate a mitochondrial localization of thyroid hormone receptor (mTR) isoform in developing brain capable of binding a TH response element (DR2) present in D-loop region of mitochondrial DNA. These results thus indicate an integrated nuclear-mitochondrial cross talk in regulation of mitochondrial transcription by TH during brain development.

  18. The Role of the Multiple Hormonal Dysregulation in the Onset of “Anemia of Aging”: Focus on Testosterone, IGF-1, and Thyroid Hormones

    Directory of Open Access Journals (Sweden)

    Marcello Maggio

    2015-01-01

    Full Text Available Anemia is a multifactorial condition whose prevalence increases in both sexes after the fifth decade of life. It is a highly represented phenomenon in older adults and in one-third of cases is “unexplained.” Ageing process is also characterized by a “multiple hormonal dysregulation” with disruption in gonadal, adrenal, and somatotropic axes. Experimental studies suggest that anabolic hormones such as testosterone, IGF-1, and thyroid hormones are able to increase erythroid mass, erythropoietin synthesis, and iron bioavailability, underlining a potential role of multiple hormonal changes in the anemia of aging. Epidemiological data more consistently support an association between lower testosterone and anemia in adult-older individuals. Low IGF-1 has been especially associated with anemia in the pediatric population and in a wide range of disorders. There is also evidence of an association between thyroid hormones and abnormalities in hematological parameters under overt thyroid and euthyroid conditions, with limited data on subclinical statuses. Although RCTs have shown beneficial effects, stronger for testosterone and the GH-IGF-1 axis and less evident for thyroid hormones, in improving different hematological parameters, there is no clear evidence for the usefulness of hormonal treatment in improving anemia in older subjects. Thus, more clinical and research efforts are needed to investigate the hormonal contribution to anemia in the older individuals.

  19. Alterations of serum concentrations of thyroid hormones and sex hormone-binding globulin, nuclear binding of tri-iodothyronine and thyroid hormone-stimulated cellular uptake of oxygen and glucose in mononuclear blood cells from patients with non-thyroidal illness

    DEFF Research Database (Denmark)

    Kvetny, J; Matzen, L

    1990-01-01

    Nuclear tri-iodothyronine (T3) binding and thyroid hormone-stimulated oxygen consumption and glucose uptake were examined in mononuclear blood cells from patients with non-thyroidal illness (NTI) in which serum T3 was significantly (P less than 0.05) depressed (0.62 +/- 0.12 (S.D.) nmol/l) compared...

  20. Effect of long-term growth hormone treatment on bone mass and bone metabolism in growth hormone-deficient men

    NARCIS (Netherlands)

    Bravenboer, N; Holzmann, PJ; ter Maaten, JC; Stuurman, LM; Roos, JC; Lips, P

    2005-01-01

    Long-term GH treatment in GH-deficient men resulted in a continuous increase in bone turnover as shown by histomorphometry. BMD continuously increased in all regions of interest, but more in the regions with predominantly cortical bone. Introduction: Adults with growth hormone (GH) deficiency have

  1. Physiological Study on the Relation of Heart Rate Variability in Ageing and Thyroid Hormone Disorder

    Directory of Open Access Journals (Sweden)

    Elsayed A. M. Shokr

    2016-04-01

    Full Text Available The present study aimed to investigate whether cardiac autonomic dysfunction in aging human might be related to an underlying thyroid disturbance. ageing has been associated with hypothyroidism and cardiac autonomic dysfunction. On the basis of body mass index (BMI, 150 patients were grouped into three groups (n = 50 48 years ± 2, 55 years ± 2 and 63 years ± 2. Electrocardiogram was recorded using PowerLab system and the time and frequency domain measures of heart rate variability (HRV were calculated. Fasting blood samples were drawn for measurement of serum thyroid stimulating hormone (TSH, total thyroxin (T4 and total triiodothyronine (T3 concentrations. The levels of TSH, T4 and T3 were not significantly different between the groups. The frequency domain HRV parameter reflecting parasympathetic tone (high-frequency normalized units, HFnu was significantly reduced in aging third groups group. The parameters which reflect sympathetic activation (Heart rate, low-frequency normalized units; LFnu and the LF/HF ratio were significantly increased in the aging group. HFnu was significantly and negatively correlated with age, whereas LFnu and LF/HF ratio were significantly and positively correlated with the above mentioned parameters. No significant relationships were noted between the HRV parameters and the levels of TSH or thyroid hormones. Cardiac autonomic dysfunction in aging human is not linked with underlying thyroid disturbance.

  2. Do Thyroxine and Thyroid-Stimulating Hormone Levels Reflect Urinary Iodine Concentrations?

    Science.gov (United States)

    Soldin, Offie P.; Tractenberg, Rochelle E.; Pezzullo, John C.

    2013-01-01

    The toxicity of environmental chemicals such as nitrates, thiocynates, and perchlorates, some therapeutics, and dietary goitrogens can lower thyroidal iodine uptake and result in hypothyroidism and goiter. Iodine sufficiency, essential for normal thyroid hormone synthesis, is critical during gestation to assure that sufficient thyroxine (T4) and iodine reach the developing fetus. Spot urinary iodide (UI) measurements are used globally to indicate and monitor iodine sufficiency of populations. In individuals, however, UI are not routinely measured; instead, normal serum thyroid-stimulating hormone (TSH) and T4 concentrations serve as surrogate indicators of iodine sufficiency as well as thyroidal health. Our objective was to examine the relationship between UI concentrations and serum T4 and TSH concentrations in individuals in an ‘‘iodine-sufficient population.’’ Using a cross-sectional sample of the US population (n = 7628) from the National Health and Nutrition Examination Survey (NHANES III; 1988–1994) database, we examined the relationship among UI, T4, and TSH in pregnant and nonpregnant women and in men (15–44 years). There was a lack of relationship between UI (or UI/Cr) concentrations and serum T4 or TSH concentrations. Therefore, TSH and T4 are not appropriate markers of UI concentrations in this population. Monitoring the status of iodine nutrition of individuals in the United States may be important because serum TSH and T4 concentrations do not indicate low iodine status. PMID:15795649

  3. APPLICATION OF ORGANIC IODINE SPECIES ANALYTICS: DETERMINING THYROID HORMONE STATUS IN ADULT DANIO RERIO AND DEVELOPING XENOPUS LAEVIS USING LC/ICP-MS

    Science.gov (United States)

    Disruption of normal thyroid function by xenobiotic chemicals is an important ecological issue. Theoretically, normal thyroid hormone (TH) homeostasis and action can be disrupted at several sites in the synthetic and elimination pathways. Indeed, xenobiotic chemicals, which are k...

  4. Preparation of quality control samples in radioimmunoassay for thyroid stimulating hormone (TSH)

    International Nuclear Information System (INIS)

    Ali, O.M.

    2006-03-01

    To days, the radioimmunoassay is becomes the best technique to analysis different concentrations of substance, especially in medical and research laboratories. Although the specificity of RIA techniques, the quality controls must takes place to give good results as possible. In this dissertation i prepared quality control samples of thyroid stimulating hormone (TSH), to use it in RIA techniques and to control the reliability results of those laboratories which used these methods. We used China production kits of RIA method to determine the level of hormone (low-normal-high) concentration. Statistical parameters were used to drown the control chart of the mean to these data.(Author)

  5. [Parathyroid hormone values in thyroid gland surgeries by harmonic scalpel and by conventional methods].

    Science.gov (United States)

    Grabovac, Stjepan; Prgomet, Drago; Janjanin, Sasa; Hadzibegović, Ana Danić

    2013-01-01

    We have examined if there are any differences in intraoperative and early postoperative concentrations of parathyroid hormone between the first group of patients, who had thyroidectomy surgery performed by harmonic scalpel, and the second group of patients operated on by standard techniqes with the use of electrocoagulation and ligature as primary hemostatic procedures. All the patients having total thyroidectomy had their blood taken in four measurement points; immediately after the induction anesthesia, 10 minutes after the first thyroid gland lobe removal, 10 minutes after total thyroid gland removal and 24 hours after the surgery. The blood samples were used to determine concentrations of the parathyroid hormone by an immunoradiometric test. The concentration comparison of parathyroid hormone between the first and the second group has not shown statistically significant difference for any of the four measurement points. The concentration comparison of parathyroid hormone within the same groups in relation to preoperational values (the first measurement point) has shown that in both groups the parathyroid hormone concentration, in all three post-incision measurement points, has been significantly lower in relation to the concentration measured before the surgery (p < 0.0005).

  6. Valor predicts the thyroid hormones in the evolution the transplant bony marrow

    International Nuclear Information System (INIS)

    Alonso, C.A.; Carnot, J.; De Castro, R.; Morera, M.L.; Garcia, I.

    1998-01-01

    In this work you values the valor I predict the thyroid hormones in the bony marrow transplant evolution as factors the metabolisms oxidative and the synthesis albumins. The patients received conditioning treatments to the transplant and in the postoperational. The received radiations were 1000 cGy lateral cube, with blocking lung, to those that were subjected 3 sessions irradiation, they are practiced a transplant marrow allogeneic

  7. Suppressing thyroid hormone signaling preserves cone photoreceptors in mouse models of retinal degeneration

    OpenAIRE

    Ma, Hongwei; Thapa, Arjun; Morris, Lynsie; Redmond, T. Michael; Baehr, Wolfgang; Ding, Xi-Qin

    2014-01-01

    Photoreceptors degenerate in a wide array of hereditary retinal diseases and age-related macular degeneration. There is currently no treatment available for retinal degenerations. While outnumbered roughly 20:1 by rods in the human retina, it is the cones that mediate color vision and visual acuity, and their survival is critical for vision. In this communication, we investigate whether thyroid hormone (TH) signaling affects cone viability in retinal degeneration mouse models. TH signaling is...

  8. Effect of thyroid hormones on the gene expression of calcium transport systems in rat muscles

    Czech Academy of Sciences Publication Activity Database

    Hudecová, S.; Vadászová, Adriana; Soukup, Tomáš; Križanová, O.

    2004-01-01

    Roč. 75, č. 8 (2004), s. 923-931 ISSN 0024-3205 R&D Projects: GA ČR GA309/03/0752 Grant - others:VEGA(SK) 2/3008; NATO(XX) 979876; SAV(SK) APVT-51-013802 Institutional research plan: CEZ:AV0Z5011922 Keywords : thyroid hormones * calcium transport systems Subject RIV: ED - Physiology Impact factor: 2.158, year: 2004

  9. Thyroid hormone actions are temperature-specific and regulate thermal acclimation in zebrafish (Danio rerio)

    OpenAIRE

    Little, Alexander G; Kunisue, Tatsuya; Kannan, Kurunthachalam; Seebacher, Frank

    2013-01-01

    Background Thyroid hormone (TH) is best known for its role in development in animals, and for its control of metabolic heat production (thermogenesis) during cold acclimation in mammals. It is unknown whether the regulatory role of TH in thermogenesis is derived in mammals, or whether TH also mediates thermal responses in earlier vertebrates. Ectothermic vertebrates show complex responses to temperature variation, but the mechanisms mediating these are poorly understood. The molecular mechani...

  10. Therapeutic potential for thyroid hormone receptor-beta selective agonists for treating obesity, hyperlipidemia and diabetes.

    Science.gov (United States)

    Grover, Gary J; Mellström, Karin; Malm, Johan

    2007-04-01

    Obesity and metabolic syndrome are increasing dramatically worldwide, contributing to cardiovascular morbidity and mortality. There are currently few safe and efficacious therapeutics for obesity and most strategies are focused on appetite suppression. Thyroid hormones reduce adiposity via increased metabolic rate, but unfortunately they cause large changes in metabolic rate and direct cardiac acceleration, making them useless for treating obesity. Thyroid hormone receptors (TRs) work as transcription factors and two subtypes exist: TRalpha and TRbeta. TRalpha mediates tachycardia and much of the metabolic rate effect, while TRbeta mediates cholesterol and TSH lowering effects of thyroid hormones. TRbeta activation modestly increases metabolic rate such that a therapeutic window of 5-10 fold increases in metabolic rate can be seen without tachycardia. This was initially studied in TRalpha(1)(-/-) mice. Recent structure activity work has resulted in the discovery of several TRbeta selective thyromimetics such as KB-141. Studies with KB-141 show that it has a 10-fold window in which therapeutic increases in metabolic rate are seen without tachycardia or cardiac hypertrophy. This agent lowers cholesterol in rats and primates. In primates, KB-141 causes significant weight and cholesterol reduction in addition to the independent risk factor Lp(a). These effects were seen without any effect on heart rate, unlike thyroid hormone (T(3)). Further work with TRbeta selective agents is warranted and recent work suggests the possibility of developing compounds that selectively penetrate different tissues which may have an even more desirable therapeutic window. Selective thyromimetics, therefore, may be useful as adjunctive therapy to appetite suppressants along with exercise and diet restriction.

  11. Growth without growth hormone in combined pituitary hormone deficiency caused by pituitary stalk interruption syndrome

    Directory of Open Access Journals (Sweden)

    Sang Soo Lee

    2017-03-01

    Full Text Available Growth hormone (GH is an essential element for normal growth. However, reports of normal growth without GH have been made in patients who have undergone brain surgery for craniopharyngioma. Normal growth without GH can be explained by hyperinsulinemia, hyperprolactinemia, elevated leptin levels, and GH variants; however, its exact mechanism has not been elucidated yet. We diagnosed a female patient aged 13 with combined pituitary hormone deficiency (CPHD caused by pituitary stalk interruption syndrome (PSIS. The patient has experienced recurrent hypoglycemic seizures since birth, but reached the height of 160 cm at the age of 13, showing normal growth. She grew another 8 cm for 3 years after the diagnosis, and she reached her final adult height of 168 cm which was greater than the midparental height, at the age of 16. The patient's blood GH and insulin-like growth factor-I levels were consistently subnormal, although her insulin levels were normal. Her physical examination conducted at the age of 15 showed truncal obesity, dyslipidemia, and osteoporosis, which are metabolic features of GH deficiency (GHD. Herein, we report a case in which a PSIS-induced CPHD patient attained her final height above mid parental height despite a severe GHD.

  12. Growth hormone treatment in non-growth hormone-deficient children

    Directory of Open Access Journals (Sweden)

    Sandro Loche

    2014-03-01

    Full Text Available Until 1985 growth hormone (GH was obtained from pituitary extracts, and was available in limited amounts only to treat severe growth hormone deficiency (GHD. With the availability of unlimited quantities of GH obtained from recombinant DNA technology, researchers started to explore new modalities to treat GHD children, as well as to treat a number of other non-GHD conditions. Although with some differences between different countries, GH treatment is indicated in children with Turner syndrome, chronic renal insufficiency, Prader-Willi syndrome, deletions/mutations of the SHOX gene, as well as in short children born small for gestational age and with idiopathic short stature. Available data from controlled trials indicate that GH treatment increases adult height in patients with Turner syndrome, in patients with chronic renal insufficiency, and in short children born small for gestational age. Patients with SHOX deficiency seem to respond to treatment similarly to Turner syndrome. GH treatment in children with idiopathic short stature produces a modest mean increase in adult height but the response in the individual patient is unpredictable. Uncontrolled studies indicate that GH treatment may be beneficial also in children with Noonan syndrome. In patients with Prader-Willi syndrome GH treatment normalizes growth and improves body composition and cognitive function. In any indication the response to GH seems correlated to the dose and the duration of treatment. GH treatment is generally safe with no major adverse effects being recorded in any condition.

  13. Genistein prevents thyroid hormone-dependent tail regression of Rana catesbeiana tadpoles by targetting protein kinase C and thyroid hormone receptor alpha.

    Science.gov (United States)

    Ji, L; Domanski, D; Skirrow, R C; Helbing, C C

    2007-03-01

    Thyroid hormone (TH)-regulated gene expression is mainly mediated by TH binding to nuclear thyroid hormone receptors (TRs). Despite extensive studies in mammalian cell lines that show that phosphorylation signaling pathways are important in TH action, little is known about their roles on TH signaling in vivo during development. Anuran metamorphosis is a postembryonic process that is absolutely dependent upon TH and tadpole tail resorption can be precociously induced by exogenous administration of 3,5,3'-triiodothyronine (T(3)). We demonstrate that genistein (a major isoflavone in soy products and tyrosine kinase inhibitor) and the PKC inhibitor (H7) prevent T(3)-induced regression of the Rana catesbeiana tadpole tail. T(3)-induced protein kinase C tyrosine phosphorylation and kinase activity are inhibited by genistein while T(3)-induced up-regulation of TRbeta mRNA, but not TRalpha mRNA, is significantly attenuated, most likely through inhibition of T(3)-dependent phosphorylation of the TRalpha protein. This phosphorylation may be modulated through PKC. These data demonstrate that T(3) signaling in the context of normal cells in vivo includes phosphorylation as an important factor in establishing T(3)-dependent tail regression during development.

  14. Serum levels of thyroid hormones and thyroid stimulating hormone in patients with biliogenic and hyperlipidaemic acute pancreatitis: Difference and value in predicting disease severity.

    Science.gov (United States)

    Yang, Ning; Zhang, Dong-Lei; Hao, Jian-Yu; Wang, Guang

    2016-04-01

    To compare retrospectively serum levels of thyroid hormones (THs) and thyroid stimulating hormone (TSH) between patients with biliogenic acute pancreatitis (BAP) and those with hyperlipidaemic acute pancreatitis (HLAP), in order to assess their value for predicting the severity of acute pancreatitis (AP). Patients with AP were divided into BAP and HLAP groups, then further divided into either a mild AP (MAP) group or a moderately severe AP (MSAP) group. Routine blood parameters were measured. Free tri-iodothyronine (FT3), free thyroxine (FT4) and TSH levels were measured. Seventy-six patients with AP were enrolled in the study. FT3 and TSH levels were significantly higher in patients with MAP than in patients with MSAP. FT4 and TSH levels were significantly lower in the HLAP group than in the BAP group. TSH levels in both MAP and MSAP patients were significantly lower in the HLAP group than in the BAP group. TSH was inversely correlated with triglyceride levels in patients with HLAP. FT3 was a risk factor for MSAP in patients with AP and also demonstrated moderate accuracy in predicting AP severity. THs and TSH decrease with the severity of AP, especially in patients with HLAP. FT3 may be a useful biomarker for the early assessment of the severity of AP. © The Author(s) 2016.

  15. Thyroid function in girls with menstrual disturbances in iodine-deficiency region

    Directory of Open Access Journals (Sweden)

    O Konstantinova

    2010-06-01

    Full Text Available The estimate the functional state of the female adolescent thyroid with menstrual cycle disorder, living in the iodine deficiency regions, 130 female adolescents with irregular menstrual cycle were examined. Hypothyroidism incidence (in them was 16.9%. In addition we considered TSH range 2.5–4.0 mU/l (highly normal TSH level the extent of which was 12.3%. High extent of antibody carriage to the thyroid (31.3% in girls with irregular menses, having high blood TSH level. There were no statistical differences between the structure of menstrual dysfunction and menstrual duration depending on thyroid function (p = 0.2383, respectively, as well as the average values of estradiol levels depending on TSH level (p = 0.3213. Thus, the influence of highly normal TSH on menstrual function development in female adolescents.

  16. Molecular aspects of thyroid hormone transporters, including MCT8, MCT10, and OATPs, and the effects of genetic variation in these transporters

    NARCIS (Netherlands)

    W.M. van der Deure (Wendy); R.P. Peeters (Robin); T.J. Visser (Theo)

    2010-01-01

    textabstractThyroid hormone is a pleiotropic hormone with widespread biological actions. For instance, adequate levels of thyroid hormone are critical for the development of different tissues such as the central nervous system, but are also essential for the regulation of metabolic processes

  17. Thyroid Hormones and Antioxidant Systems: Focus on Oxidative Stress in Cardiovascular and Pulmonary Diseases

    Directory of Open Access Journals (Sweden)

    Antonio Mancini

    2013-12-01

    Full Text Available In previous works we demonstrated an inverse correlation between plasma Coenzyme Q10 (CoQ10 and thyroid hormones; in fact, CoQ10 levels in hyperthyroid patients were found among the lowest detected in human diseases. On the contrary, CoQ10 is elevated in hypothyroid subjects, also in subclinical conditions, suggesting the usefulness of this index in assessing metabolic status in thyroid disorders. A Low-T3 syndrome is a condition observed in several chronic diseases: it is considered an adaptation mechanism, where there is a reduction in pro-hormone T4 conversion. Low T3-Syndrome is not usually considered to be corrected with replacement therapy. We review the role of thyroid hormones in regulation of antioxidant systems, also presenting data on total antioxidant capacity and Coenzyme Q10. Published studies suggest that oxidative stress could be involved in the clinical course of different heart diseases; our data could support the rationale of replacement therapy in low-T3 conditions.

  18. [Laryngeal effect of experimental postnatal hypothyroidism: do thyroid hormone receptors change?].

    Science.gov (United States)

    Eryılmaz, Aylin; Günel, Ceren; Eliyatkın, Nuket; Cesur, Gökhan; Türe, Mevlüt; Başal, Yeşim

    2016-01-01

    In this study, we aimed to investigate the laryngeal histopathological alterations and thyroid hormone receptors in rats with experimentally-induced postnatal hypothyroidism. In this prospective, randomized study, pregnant Wistar albino rats were followed and newborn 20 Wistar albino rat pups were included in the study. The pups were randomly divided into two groups: In group 1 (methimazole (MMI)-induced hypothyroidism group), the mothers and pups were given MMI added water up to 90th day, as the pups were fed with breast milk for 19 to 22 days. In group 2 (control group), the mothers and pups were fed with MMI-free water up to 90th days. When the pups were 90 days of age, they were decapitated and their larynx was removed. Their larynx was evaluated for edema, inflammation, goblet cells, and thyroid hormone receptors (TR-α, TR-β). Nine larynx samples for group 1 and eight for group 2 were studied. There was a significant difference in inflammation between the groups with slightly lower in the hypothyroidism group (p=0.009). The TR-α, TR-β, and edema were significantly higher in the hypothyroidism group (p=0.002, p=0.029, p=0.029). There was no significant difference in the Goblet cells between the groups (p=0.637). Histopathologically increased laryngeal edema and increased thyroid hormone receptors were found, shedding light on the mechanism of voice changes in hypothyroidism.

  19. Thyroid Hormones and Antioxidant Systems: Focus on Oxidative Stress in Cardiovascular and Pulmonary Diseases

    Science.gov (United States)

    Mancini, Antonio; Raimondo, Sebastiano; Di Segni, Chantal; Persano, Mariasara; Gadotti, Giovanni; Silvestrini, Andrea; Festa, Roberto; Tiano, Luca; Pontecorvi, Alfredo; Meucci, Elisabetta

    2013-01-01

    In previous works we demonstrated an inverse correlation between plasma Coenzyme Q10 (CoQ10) and thyroid hormones; in fact, CoQ10 levels in hyperthyroid patients were found among the lowest detected in human diseases. On the contrary, CoQ10 is elevated in hypothyroid subjects, also in subclinical conditions, suggesting the usefulness of this index in assessing metabolic status in thyroid disorders. A Low-T3 syndrome is a condition observed in several chronic diseases: it is considered an adaptation mechanism, where there is a reduction in pro-hormone T4 conversion. Low T3-Syndrome is not usually considered to be corrected with replacement therapy. We review the role of thyroid hormones in regulation of antioxidant systems, also presenting data on total antioxidant capacity and Coenzyme Q10. Published studies suggest that oxidative stress could be involved in the clinical course of different heart diseases; our data could support the rationale of replacement therapy in low-T3 conditions. PMID:24351864

  20. Hyperemesis gravidarum affects maternal sanity, thyroid hormones and fetal health: a prospective case control study.

    Science.gov (United States)

    Buyukkayaci Duman, Nuriye; Ozcan, Oguzhan; Bostanci, M Ömer

    2015-08-01

    Hyperemesis gravidarum (HG) is a condition of severe nausea or vomiting accompanied by various complications during pregnancy. In the present study, we aimed to demonstrate the effects of HG on mother and fetus health. Control and case group were arranged from 50 healthy pregnant women and 50 pregnant women with HG. Information about the participant women was gathered with data collection form and Beck's Depression Inventory (BDI) and State Anxiety Inventory (SAI) were administered to the women. Following an abortion or delivery, the data about birth complications and neonatal health were collected. All laboratory results (blood count, thyroid hormones, electrolyte values and biochemical parameters) were gathered from the laboratory information system used in the hospital. It was found that in the case group, mean postpartum weight, serum hemoglobin, hematocrit and thyroid stimulant hormone levels were lower than control group (p < 0.01). Conversely, case group women have higher T3 and T4 levels than control group (p < 0.01). There was no significant difference between the two groups in terms of intrauterine growth retardation, low birth weight and abortion but it was observed that women with HG had often delivered prematurely. The mean scores of BDI and SAI in the case group were higher than those of control group. These results suggested that HG may have adverse effects on both mother and baby's health. Pregnant women with HG should be provided with training and consultancy services and be closely monitored in terms of anemia and thyroid hormones.

  1. Three-compartmental analysis of effects of D-propranolol on thyroid hormone kinetics

    International Nuclear Information System (INIS)

    Van Der Heijden, J.T.M.; Krenning, E.P.; Van Toor, H.; Hennemann, G.; Docter, R.

    1988-01-01

    Tracer thyroxine (T 4 ), 3,3',5-triiodothyronine (T 3 ), and 3,3',5'-triiodothyronine (rT 3 ) kinetic studies were performed in normal T 4 substituted subjects before and during oral D-propranolol treatment to determine whether changes in thyroid hormone metabolism in a propranolol-induced low-T 3 syndrome result from inhibition of 5'-deiodination or inhibition of transport of iodothyronines into tissues. Data were analyzed according to a three-compartmental model of distribution and metabolism. No changes were observed in size of the three T 4 compartments or in fractional and mass transfer rates of T 4 from plasma to the rapidly (REP) and slowly (SEP) equilibrating pools. Serum T 3 , free T 3 , T 3 plasma pool, T 3 mass transfer rate to REP and SEP, and the T 3 pool masses were all significantly decreased during propranolol to a similar extent as the T 3 plasma production rate (PR). It is concluded that the D-propranolol-induced changes in thyroid hormone metabolism, resulting in a low-T 3 syndrome, are due to inhibition of thyroid hormone deiodination. This is in contrast to the low-T 3 syndrome during caloric deprivation, which results from inhibition of transport of iodothyronines into the liver

  2. Modifications of thyroid hormones secretion and production in newborn rats from hyperthyroic dams

    International Nuclear Information System (INIS)

    Silveira, M.F.G.; Neves, E.S.S.; Neves, S.R.S.; Catanho, M.T.J.A.

    1997-01-01

    The onset of fetal thyroid function occurs about 17-18 days after conception in the rat. The maternal hyperthyroidism which occurs during gestation provokes alterations in the rat after its birth; due to this alterations, we decided to analyze the metabolic and hormonal modification in the newborn rats. The hyperthyroidism was induced in normal dams, which were being trated for 2 days with T4 2mg (thyroxine per 100g body wt/day) before mating. Another dam group which was submitted to an inducement of hyperthyroidism maintained the treatment with T4 and six day after gestation were being treated for 9 days. It was seen that the rat which was born from hyperthyroic dams suffered alterations on its T4 and T3 hormone levels concerning the days 10, 20 and 30 after birth. T4 e T3 were performed with Immu chem cooted tube - I 125 RIA KIT .The administration of T4 affected the fetal thyroid function gland to, causing a decrease of both T4 and T3 levels, as was also modifications on their weight and size, even after the birth, indicating that the maternal hyperthyroidism influences on the post-natal life of the rat. The growth is affected throught post-natal life by thyroid hormones, which have a facilitatory influence on GH economy, as opposed to the inhibitory effects on TSH economy. (author). 12 refs., 4 figs

  3. Aluminium effects on thyroid gland function: iodide uptake, hormone biosynthesis and secretion.

    Science.gov (United States)

    Orihuela, Daniel

    2011-11-01

    The effects of aluminium (Al) on thyroid function were evaluated in adult Wistar rats intraperitoneally (i.p) injected with 7 mg Al (as lactate)/kg body weight (b.w) per day during a six week period. The time-course kinetics of Na(125)I (3 μCi per 100 g b.w, i.p) was analysed by measuring gamma-radioactivity of thyroid, serum, serum protein precipitate and bile, at times ranging from 2 to 96 h post-dosing. In Al-treated group the (125)I(-) thyroid uptake at 24 h (15,840 ± 570 vs. 18,030 ± 630 dpm/mg, Pthyroid tissue were increased in Al-treated rats. The serum concentrations of total thyroxine (T4, 3.78 ± 0.14 vs. 4.68 ± 0.12 μg/dL, Pthyroid iodide uptake and hormones secretion by a mechanism involving the induction of an oxidative stress state, however, these changes could be managed by the hypothalamus-pituitary-thyroid endocrine axis. We can conclude that in adult rats the Al would not act as a thyroid disruptor. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Expression of urocortin and corticotropin-releasing hormone receptors in the horse thyroid gland.

    Science.gov (United States)

    Squillacioti, Caterina; De Luca, Adriana; Alì, Sabrina; Paino, Salvatore; Liguori, Giovanna; Mirabella, Nicola

    2012-10-01

    Urocortin (UCN) is a 40-amino-acid peptide and a member of the corticotropin-releasing hormone (CRH) family, which includes CRH, urotensin I, sauvagine, UCN2 and UCN3. The biological actions of CRH family peptides are mediated via two types of G-protein-coupled receptors, namely CRH type 1 receptor (CRHR1) and CRH type 2 receptor (CRHR2). The biological effects of these peptides are mediated and modulated not only by CRH receptors but also via a highly conserved CRH-binding protein (CRHBP). Our aim was to investigate the expression of UCN, CRHR1, CRHR2 and CRHBP by immunohistochemistry, Western blot and reverse transcription with the polymerase chain reaction (RT-PCR) in the horse thyroid gland. The results showed that UCN, CRHR1 and CRHR2 were expressed in the thyroid gland, whereas CRHBP was not expressed. Specifically, UCN immunoreactivity (-IR) was found in the thyroid follicular cells, CRHR2-IR in the C-cells and CRHR1-IR in blood vessels. Western blot analysis and RT-PCR experiments confirmed the immunohistochemical data. These results suggest that a regulatory system exists in the mammalian thyroid gland based on UCN, CRHR1 and CRHR2 and that UCN plays a role in the regulation of thyroid physiological functions through a paracrine mechanism.

  5. Establishment of Trimester-Specific Reference Intervals for Thyroid Hormones in Korean Pregnant Women

    Science.gov (United States)

    Moon, Hee-Won; Chung, Hee-Jung; Park, Chul-Min; Hur, Mina

    2015-01-01

    Background Establishment of trimester- and assay-specific reference intervals for every population is recommended. The aim of this study was to establish a trimester- and assay-specific reference interval for thyroid-stimulating hormone (TSH) and free thyroxine (FT4) in Korean pregnant women. Methods From April 2012 to December 2012, 531 pregnant women receiving prenatal care and 238 age-matched, non-pregnant women were enrolled in this study. After excluding patients with pregnancy-associated complications or thyroid-specific autoantibody, 465 pregnant and 206 non-pregnant women were included. Non-parametric analysis (2.5-97.5th percentile) was performed to determine the reference interval. Levels of TSH and FT4 were determined by electrochemiluminescence immunoassay (Elecsys thyroid tests, Roche Diagnostics, Germany). Results The TSH reference intervals were 0.01-4.10, 0.01-4.26, and 0.15-4.57 mIU/L for the first, second, and third trimester, respectively. From the first trimester to the third trimester, the median TSH levels showed a significantly increasing trend (Preference intervals were 0.83-1.65, 0.71-1.22, and 0.65-1.13 ng/dL for the first, second, and third trimester, respectively, showing a significantly decreasing trend (Preference intervals in pregnant women is essential for accurate assessment of thyroid function. Our population-specific and method-specific reference intervals will be useful for screening Korean pregnant women for thyroid disease. PMID:25729721

  6. Thyroid Hormone Therapy for Older Adults with Subclinical Hypothyroidism

    DEFF Research Database (Denmark)

    Stott, David J.; Rodondi, Nicolas; Kearney, Patricia M.

    2017-01-01

    BACKGROUND: The use of levothyroxine to treat subclinical hypothyroidism is controversial. We aimed to determine whether levothyroxine provided clinical benefits in older personswith this condition. METHODS: We conducted a double-blind, randomized, placebo-controlled, parallel-group trial involving...... 737 adults who were at least 65 years of age and who had persisting subclinical hypothyroidism (thyrotropin level, 4.60 to 19.99 mIU per liter; free thyroxine level within the reference range). A total of 368 patients were assigned to receive levothyroxine (at a starting dose of 50 μg daily, or 25 μg...... if the body weight was Hypothyroid Symptomsscore and Tiredness score on a thyroid...

  7. Follicular Thyroid Carcinoma in a Country of Endemic Iodine Deficiency (1994–2013

    Directory of Open Access Journals (Sweden)

    Edmund Muonir Der

    2018-01-01

    Full Text Available Background. Follicular thyroid cancer (FTC has historically been linked to iodine deficiency. Although Ghana is among the iodine deficient regions of the world, the proportions, trends, and the clinical features of FTCs have not been studied as a single disease entity. The aim of this study was to determine the relative frequencies, trends, and the clinicopathological characteristics of FTCs among all thyroid malignancies in our institution. Materials and Methods. This was a retrospective study from January 1994 to December 2013. Data were analysed using SPSS software version 23 (Chicago and Graph pad prism version 5.00. Results. Follicular thyroid cancer was the second thyroid malignancy (35.0% and showed a gradual rise in relative proportions over the period. The male-female ratio was 1 : 1.5. The mean ages were 46.9 (SD ±17.3 for males and 46.4 (SD ±13.3 years for females. Enlarged palpable anterior neck swelling was the commonest symptom in males (86.7% and females (91.3% (P=0.730. Hurthle cell carcinoma was the commonest variant of FTC, with 26.7% males and 10.6% females (P=0.116. Distant spread was found in 23.3% of males compared to 19.1% of females (P=0.633. The common sites of distant spread were bones (57.2% in males and cervical lymph nodes (44.4% in females (P=0.106. Conclusion. Follicular thyroid cancer was the second common thyroid malignancy (35.0% with a gradual rise in trend over the study period and male-female ratio of 1.5 : 1. Large anterior neck swelling was the commonest clinical presentation of FTC.

  8. The spectrum of thyroid disorders in an iodine-deficient community: the Pescopagano survey.

    Science.gov (United States)

    Aghini-Lombardi, F; Antonangeli, L; Martino, E; Vitti, P; Maccherini, D; Leoli, F; Rago, T; Grasso, L; Valeriano, R; Balestrieri, A; Pinchera, A

    1999-02-01

    We carefully assessed thyroid status and goiter by ultrasound in 1411 subjects virtually representing the entire resident population of Pescopagano, an iodine-deficient village of Southern Italy. Median urinary iodine excretion was 55 microg/L. The prevalence of goiter was 16.0% in children and 59.8% in adults. Thyroid nodularity was 0.5% in children and progressively increased with age to 28.5% in the 56- to 65-yr-old group. The prevalence of present or past hyperthyroidism was 2.9%, including 9 cases with toxic diffuse goiter and 20 with toxic nodular goiter. Functional autonomy was rare in children, progressively increased with age up to 15.4% in the elderly, and was related to nodular goiter. The prevalences of overt and subclinical hypothyroidism in the adults were 0.2% and 3.8%, respectively. Serum autoantibodies to thyroglobulin and thyroperoxidase were detected in 12.6% of the entire population. The prevalence of diffuse autoimmune thyroiditis was 3.5%, being very low in children. Thyroid cancer was found in only 1 case. In conclusion, in the present survey of an iodine-deficient community, a progressive increase with age of goiter prevalence, thyroid nodularity, and functional autonomy was observed. Hyperthyroidism was twice as high as that reported in iodine-sufficient areas, mainly due to an increased frequency of toxic nodular goiter. Although low titer serum thyroid antibodies were relatively frequent, the prevalences of both overt and subclinical autoimmune hypothyroidism were not different from those observed in iodine-sufficient areas.

  9. Responses of chickens subjected to thyroid hormone depletion-repletion.

    Science.gov (United States)

    Rosebrough, R W; Russell, B A; Richards, M P

    2007-06-01

    The purpose of this experiment was to determine the relationship between lipid metabolism and the expression of specific genes in chickens fed methimazole to produce hypothyroidism. Male, broiler chickens growing from 14 to 28 days of age were fed diets containing 18% crude protein and either 0 or 1 g methimazole per kg of diet. At 28 days, these two groups were further subdivided into groups receiving 18% crude protein diets containing either 0 or 1 mg triiodothyronine (T(3)) per kg. Birds were sampled at intervals from 0 to 120 h. Measurements taken included in vitro lipogenesis (IVL), malic enzyme (ME), isocitrate dehydrogenase (ICD-NADP), aspartate aminotransferase (AAT) activities and the expression of the genes for ME, fatty acid synthase (FAS), NADP-ICD, AAT and acetyl coenzyme carboxylase (ACC). Gene expression was estimated with real time RT-PCR assays. Expression rates were noted as C(t)'s. Dietary methimazole decreased IVL and ME at 28 days of age. T(3) and supplementation for 1 day restored both IVL and ME. Paradoxically, continuing T(3) replenishment for a longer period decreased IVL without affecting ME activity. Although methimazole decreased ME gene expression, there was only a transitory relationship between enzyme activity and gene expression when plasma T(3) was replenished with exogenous T(3). These data explain the apparent dichotomies in lipid metabolism elicited by changes in the thyroid state of animals. Most metabolic changes in response to feeding T(3) occurred within a short period of time, suggesting that changes in intermediary metabolism preceded morphological changes. Furthermore, the thyroid state of the animal will determine responses to exogenous T(3).

  10. Reproductive Factors but Not Hormonal Factors Associated with Thyroid Cancer Risk: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Yijuan Cao

    2015-01-01

    Full Text Available Many studies have investigated the association between hormonal and reproductive factors and thyroid cancer risk but provided contradictory and inconclusive findings. This review was aimed at precisely estimating this association by pooling all available epidemiological studies. 25 independent studies were retrieved after a comprehensive literature search in databases of PubMed and Embase. Overall, common hormonal factors including oral contraceptive and hormone replacement therapy did not alter the risk of thyroid cancer. Older age at menopause was associated with weakly increased risk of thyroid cancer in overall analysis (RR = 1.24, 95% CI 1.00–1.53, P=0.049; however, longer duration of breast feeding was related to moderately reduced risk of thyroid cancer, suggested by pooled analysis in all cohort studies (RR = 0.7, 95% CI 0.51–0.95, P=0.021. The pooled RR in hospital-based case-control studies implicated that parous women were more susceptible to thyroid cancer than nulliparous women (RR = 2.30, 95% CI 1.31–4.04, P=0.004. The present meta-analysis suggests that older age at menopause and parity are risk factors for thyroid cancer, while longer duration of breast feeding plays a protective role against this cancer. Nevertheless, more relevant epidemiological studies are warranted to investigate roles of hormonal and reproductive factors in thyroid carcinogenesis.

  11. Association between organophosphate pesticides exposure and thyroid hormones in floriculture workers

    International Nuclear Information System (INIS)

    Lacasana, Marina; Lopez-Flores, Inmaculada; Rodriguez-Barranco, Miguel; Aguilar-Garduno, Clemente; Blanco-Munoz, Julia; Perez-Mendez, Oscar; Gamboa, Ricardo; Bassol, Susana; Cebrian, Mariano E.

    2010-01-01

    The ability of organophosphate pesticides to disturb thyroid gland function has been demonstrated by experimental studies on animal, but evidence of such effects on human remains scarce. The aim of this study was to assess the association between exposure to organophosphate compounds and serum levels of thyroid hormones in floriculture workers. A longitudinal study was conducted on 136 male subjects from the State of Mexico and Morelos, Mexico, occupationally exposed to organophosphate pesticides, during agricultural periods of high (rainy season) and low (dry season) levels of pesticide application. Using a structured questionnaire, a survey was carried out on sociodemographic characteristics, anthropometry, clinical history, alcohol and tobacco consumption, residential chemical exposure, and occupational history. Urine and blood samples were taken the day after pesticide application to determine urine dialkylphosphate (DAP) levels, serum levels of TSH, total T 3 , total T 4 , serum PON1 activity, and serum p,p'-DEE levels. The analysis of the association between DAP levels and thyroid hormonal profile was carried out using multivariate generalized estimating equation (GEE) models. Our results showed an increase in both TSH and T 4 hormones in serum associated with a increase in total dimethylphosphate levels (ΣDMP) in urine (p-trend 3 serum levels with an increase of ΣDMP levels in the urine (p-trend = 0.053). These results suggest that exposure to organophosphate pesticides may be responsible of increasing TSH and T 4 serum hormone levels and decreasing T 3 serum hormone levels, therefore supporting the hypothesis that organophosphate pesticides act as endocrine disruptors in humans.

  12. Barhl1 is directly regulated by thyroid hormone in the developing cerebellum of mice

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Hongyan, E-mail: hongyan_dong@hc-sc.gc.ca [Hazard Identification Division, Environmental Health Science and Research Bureau, Health Canada, 50 Columbine Driveway, Ottawa, Ontario, Canada K1A 0K9 (Canada); Yauk, Carole L. [Mechanistic Studies Division, Environmental Health Science and Research Bureau, Health Canada, 50 Columbine Driveway, Ottawa, Ontario, Canada K1A 0K9 (Canada); Wade, Michael G. [Hazard Identification Division, Environmental Health Science and Research Bureau, Health Canada, 50 Columbine Driveway, Ottawa, Ontario, Canada K1A 0K9 (Canada)

    2011-11-11

    Highlights: Black-Right-Pointing-Pointer Thyroid hormone receptor binds to the promoter region of Barhl1. Black-Right-Pointing-Pointer Barhl1 expression in cerebellum is negatively regulated by thyroid hormone. Black-Right-Pointing-Pointer Negative regulation of Barhl1 by thyroid hormone was confirmed in vitro. Black-Right-Pointing-Pointer Thyroid hormone may play a role in normal brain development through transcriptional control of Barhl1. -- Abstract: Thyroid hormones (THs) are essential for the brain development. Despite considerable effort, few genes directly regulated by THs have been identified. In this study, we investigate the effects of THs on the regulation of Barhl1, a transcription factor that regulates sensorineural development. Using DNA microarray combined with chromatin immunoprecipitation (ChIP-chip), we identified a TR{beta} binding site in the promoter of Barhl1. The binding was further confirmed by ChIP-PCR. The site is located approximately 755 bp upstream of the transcription start site. Reporter vectors containing the binding site or mutated fragments were transfected into GH3 cells. T3 treatment decreased the transcriptional activity of the wild fragment but not the mutant. Two 28 bp oligonucleotides containing sequences that resemble known TH response elements (TREs) were derived from this binding site and DNA-protein interaction was performed using electrophoretic mobility shift assays (EMSA). Binding analysis in a nuclear extract containing TR{beta} revealed that one of these fragments bound TR{beta}. This complex was shifted with the addition of anti-TR{beta} antibody. We investigated Barhl1 expression in animal models and TH-treated cultured cells. Both long term treatment with 6-propyl-2-thiouracil and short-term treatment with 0.05% methimazole/1% sodium perchlorate (both treatments render mice hypothyroid) resulted in up-regulation of Barhl1. TH supplementation of hypothyroid mice caused a decrease in the expression of Barhl1

  13. Diagnosis and treatment of hypothyroidism in TSH deficiency compared to primary thyroid disease: pituitary patients are at risk of under-replacement with levothyroxine.

    Science.gov (United States)

    Koulouri, Olympia; Auldin, Mohammed A; Agarwal, Ravi; Kieffer, Veronica; Robertson, Carole; Falconer Smith, James; Levy, Miles J; Howlett, Trevor A

    2011-06-01

    Achieving optimal thyroid hormone replacement is more difficult in TSH deficiency compared to primary hypothyroidism because of the inability to be guided by serum TSH levels. A combination of clinical symptoms and free thyroxine levels (fT4) are typically used to make a diagnosis and monitor replacement. We investigated the diagnosis of TSH deficiency in patients with pituitary disease and the adequacy of levothyroxine replacement compared with primary thyroid disease. Using our department's clinical information system, we identified all patients with a diagnosis of any type of pituitary tumour who had been seen in clinic over a 2-year period. We divided the patients into those at high risk and low risk of TSH deficiency based on the presence of macroadenoma and/or intervention by surgery or radiotherapy. We compared fT4 values in these patients with values in patients with primary thyroid disease in our thyrotoxicosis shared-care scheme (TSC) and hypothyroid register within the same timescale, assessing only those samples considered euthyroid in which TSH was in the normal range. A database query identified 525 patients with a pituitary tumour of whom 344 were considered at high risk of TSH deficiency. A free T4 (fT4) value was found for 514 patients (97·9%). TSC and thyroid register databases revealed fT4 values for comparison with simultaneous normal TSH in patients on no treatment (n = 3777 samples) or on levothyroxine alone (n = 11,805). fT4 levels overall were lower in pituitary patients than in equivalent controls. Of the high risk group not taking levothyroxine 17% had a free T4 ≤ 11 pmol/l compared to only 8·4% of untreated controls. Furthermore, 38·9% of patients on levothyroxine had a free T4 ≤ 13 pmol/l compared to 9·5% of controls on levothyroxine with previous thyrotoxicosis and 13·4% of controls with primary hypothyroidism. Median fT4 in controls on levothyroxine was 16 pmol/l and 20-80th centile range was 14-19 pmol/l. Levothyroxine doses

  14. The evolution of endothermy is explained by thyroid hormone-mediated responses to cold in early vertebrates.

    Science.gov (United States)

    Little, Alexander G; Seebacher, Frank

    2014-05-15

    The evolution of endothermy is one of the most intriguing and consistently debated topics in vertebrate biology, but the proximate mechanisms that mediated its evolution are unknown. Here, we suggest that the function of thyroid hormone in regulating physiological processes in response to cold is key to understanding the evolution of endothermy. We argue that the capacity of early chordates to produce thyroid hormone internally was the first step in this evolutionary process. Selection could then act on the capacity of thyroid hormone to regulate metabolism, muscle force production and cardiac performance to maintain their function against the negative thermodynamic effects of decreasing temperature. Thyroid-mediated cold acclimation would have been the principal selective advantage. The actions of thyroid hormone during cold acclimation in zebrafish are very similar to its role during endothermic thermogenesis. The thyroid-mediated increases in metabolism and locomotor performance in ectotherms eventually resulted in sufficient heat production to affect body temperature. From this point onwards, increased body temperature per se could be of selective advantage and reinforce thyroid-induced increases in physiological rates. Selection for increased body temperature would promote those mechanisms that maximise heat production, such as increased Na(+)/K(+)-ATPase activity, futile cycling by SERCA, and mitochondrial uncoupling, all of which are regulated by thyroid hormone. The specific end point of this broader evolutionary process would be endothermic thermoregulation. However, considering the evolution of endothermy in isolation is misleading because the selective advantages that drove the evolutionary process were independent from endothermy. In other words, without the selective advantages of thyroid-mediated cold acclimation in fish, there would be no endotherms. © 2014. Published by The Company of Biologists Ltd.

  15. Multiple endocrinopathies (growth hormone deficiency, autoimmune hypothyroidism and diabetes mellitus in Kearns-Sayre syndrome

    Directory of Open Access Journals (Sweden)

    A. Berio

    2013-06-01

    Full Text Available Kearns-Sayre syndrome is characterized by onset before 20 years, chronic progressive external opthalmoplegia, pigmentary retinal degeneration, and ataxia (and/or hearth block, and/or high protein content in the cerebrospinal fluid in the presence of mtDNA rearrangements. Multiple endocrine dysfunction associated with this syndrome was rarely reported. In this paper, the Authors report on a female patient with Kearns-Sayre syndrome with large heteroplasmic mtDNA deletion, absence of cytochrome c oxidase in many muscle fibers, partial GH deficiency, hypothyroidism and subsequently insulin dependent diabetes mellitus (IDDM. Anti-thyroid peroxidase and antithyreoglobulin antibodies were present in high titer in serum while anti-islet cell antibodies were absent. The patient developed thyroiditis with Hashimoto encephalopathy. The presence of GH deficiency, autoimmune thyroiditis with hypothyroidism and IDDM distinguishes this case from others and confirms the association of Kearns-Sayre syndrome with multiple endocrine dysfunction. Hashimoto encephalopathy and anti-thyroideal antibodies suggest that in this patient, predisposed by a genetic factor (a mitochondrial deletion anti-thyroideal antibodies may have contributed to the hypothyroidism and, by interfering with cerebral mitochondrial function, may have caused the encephalopathy. GH deficiency and IDDM can be attributed to oxidative phosphorylation deficiency but the autoimmunity may also have played a role in the production of glandular insufficiencies. It seems important to search for endocrine autoimmunity in every case of KSS.

  16. Comparison of method-related reference intervals for thyroid hormones: studies from a prospective reference population and a literature review.

    Science.gov (United States)

    Barth, Julian H; Luvai, Ahai; Jassam, Nuthar; Mbagaya, Wycliffe; Kilpatrick, Eric S; Narayanan, Deepa; Spoors, Shirley

    2018-01-01

    Introduction Reference intervals are dependent on the reference population, the analytical methods and the way the data are handled statistically. Individual method-related differences have been studied but the comparative differences in reference intervals have not. Methods We studied a reference population of healthy adult subjects and measured free thyroxine and thyroid-stimulating hormone by the four most commonly used analytical platforms used in the UK. Subjects were excluded if they were > 65 years or had positive thyroid peroxidase antibodies. We also performed a systematic literature review of thyroid hormone reference interval studies in non-pregnant adults. Results In total, 303 subjects were recruited and 42 excluded. The central 95th centile values for thyroid-stimulating hormone (mIU/L) were Abbott Architect (0.51-3.67); Beckman Unicel DxI (0.57-3.60); Roche Cobas (0.60-4.31) and Siemens Advia Centaur XP (0.63-4.29). The 95th centile values for thyroxine (pmol/L) were Abbott Architect (10.6-15.5); Beckman Unicel DxI (7.9-13.0); Roche Cobas (12.5-19.6) and Siemens Advia Centaur XP (11.8-19.0). We identified 55 papers describing thyroid reference intervals in male and non-pregnant female adults. The values for upper and lower reference intervals by manufacturer varied but were not significantly different for thyroid-stimulating hormone but were for thyroxine. Discussion Our study demonstrates clearly that there are marked variations in the reference intervals for thyroid hormones between analytical platforms. There is an urgent need for standardization of thyroid hormone assays to permit transferability of results. Until then, guidelines will need to reflect this method-related difference.

  17. Thyroid cancer incidence in iodine deficient areas exposed to radiation after Chernobyl accident

    International Nuclear Information System (INIS)

    Szybinski, Z.; Mazurek-Przybylik, E.

    1996-01-01

    In two districts of Southern Poland; Krakow and Nowy Sacz (2 million people), standardized thyroid cancer incidence rate IR was evaluated from 1976 to 1992. This area was classified as a moderate iodine deficiency endemic goiter region and belonged to the most contaminated areas in Poland after Chernobyl accident. Recalculated - in terms of real iodine intake-thyroid commitment equivalent dose in the youngest age groups reached 100 mSv. The aim of the study was to evaluate, 6 years after Chernobyl accident, thyroid cancer incidence rate and histotype. Age and sex specific incidence rate in Krakow for male was 0.827 and for female 3.093 and 0.93 and 2.164 for Nowy Sacz respectively. There was no increase of IR in the group of age 0-19 yrs, however in the group over 44 yrs in females in the period of time 1989-1992 significant increase of follicular cancer was observed. In the histotype, the follicular cancerpredominated over the papillary one: 42,9% against 33,6%. Predominance of the follicular cancer is typical for iodine deficient area. Significant increase of the follicular cancer may be due to the increase of iodine deficiency. (author). 14 refs, 1 fig., 5 tabs

  18. The Type 3 Deiodinase is a Critical Determinant of Appropriate Thyroid Hormone Action in the Developing Testis

    NARCIS (Netherlands)

    M. Martinez, M. (Elena); A. Karaczyn, A. (Aldona); J. Stohn, J. (Patrizia); W. Donnelly, W. (William); W. Croteau, W. (Walburga); P. Peeters, P. (Robin); V.A. Galton (Valerie Anne); D. Forrest (Douglas); D.L. St Germain (Donald); A. Hernandez (Arturo)

    2016-01-01

    textabstractTimely and appropriate levels of thyroid hormone (TH) signaling are necessary to ensure normal developmental outcomes in many tissues. Studies using pharmacological models of altered TH status have revealed an influence of these hormones on testis development and size, but little

  19. Effects of hypergravity exposure on the developing central nervous system: possible involvement of thyroid hormone

    Science.gov (United States)

    Sajdel-Sulkowska, E. M.; Li, G. H.; Ronca, A. E.; Baer, L. A.; Sulkowski, G. M.; Koibuchi, N.; Wade, C. E.

    2001-01-01

    The present study examined the effects of hypergravity exposure on the developing brain and specifically explored the possibility that these effects are mediated by altered thyroid status. Thirty-four timed-pregnant Sprague-Dawley rats were exposed to continuous centrifugation at 1.5 G (HG) from gestational Day 11 until one of three key developmental points: postnatal Day (P) 6, P15, or P21 (10 pups/dam: 5 males/5 females). During the 32-day centrifugation, stationary controls (SC, n = 25 dams) were housed in the same room as HG animals. Neonatal body, forebrain, and cerebellum mass and neonatal and maternal thyroid status were assessed at each time point. The body mass of centrifuged neonates was comparatively lower at each time point. The mass of the forebrain and the mass of the cerebellum were maximally reduced in hypergravity-exposed neonates at P6 by 15.9% and 25.6%, respectively. Analysis of neonatal plasma suggested a transient hypothyroid status, as indicated by increased thyroid stimulating hormone (TSH) level (38.6%) at P6, while maternal plasma TSH levels were maximally elevated at P15 (38.9%). Neither neonatal nor maternal plasma TH levels were altered, suggesting a moderate hypothyroid condition. Thus, continuous exposure of the developing rats to hypergravity during the embryonic and neonatal periods has a highly significant effect on the developing forebrain and cerebellum and neonatal thyroid status (P thyroid hormone in mediating the effect of hypergravity in the developing central nervous system and begin to define the role of TH in the overall response of the developing organism to altered gravity.

  20. Relationship between thyroid stimulating hormone and various components of metabolic syndrome

    International Nuclear Information System (INIS)

    Majeed, S.; Hashim, R.

    2015-01-01

    To determine the relation between thyroid stimulating hormone and various components of metabolic syndrome. Study Design: Descriptive cross-sectional study. Place and Duration of Study: Pathology department, Army Medical College of National University of Sciences and Technology (NUST) Islamabad and Military Hospital (MH), Rawalpindi, Pakistan; from January to March 2013. Material and Methods: Hundred adult inhabitants (30-60 years) of Rawalpindi participated in this study. Subjects who fulfilled the WHO criteria for metabolic syndrome (MetS) were included and those who had any thyroid illness, or were using any thyroid medications were excluded from this study. For thyroid function tests (TFT's), serum thyroid stimulating hormone (TSH), total tri-iodothyronine (TT3), free throxine (FT4) were estimated. Insulin resistance (IR) was measured by Homeostasis Model Assessment for IR (HOMA-IR). Data was analyzed by SPSS-18. Results: Out of 50 subjects of control group, 26 (52%) were male and 24 (48%) were female. Basal metabolic rate (BMI), serum triglyceride (TG), HOMA-IR were higher and serum high density lipoprotein cholesterol (HDL-c) was lower in MetS patients. There was no significant difference in serum TT3 and FT4 between MetS patients and control group, however, mean serum TSH levels were higher in MetS (2.622 + 0.924 vs 5.002 + 1.074 mIU/l, p<0.001). In correlation analysis, serum TSH was positively and significantly correlated with BMI (r=0.344, p=0.014) and HOMA-IR (r=0.419, p<0.002). Conclusion: These results suggest that serum TSH correlates with various components of metabolic syndrome patients. Analysis of serum TSH levels in metabolic syndrome patients may prove beneficial in preventing the various cardiometabolic complications in such patients. (author)