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1.
Endocr Rev ; 41(6)2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-32845332

RESUMEN

Graves' hyperthyroidism is characterized by the presence of autoantibodies that stimulate the thyroid-stimulating hormone receptor (TSHR), resulting in uncontrolled secretion of excessive thyroid hormone. Conventional treatments, including antithyroid medication, radioiodine, or surgery have remained largely unchanged for the past 70 years and either lack efficacy for many patients, or result in lifelong thyroid hormone replacement therapy, in the case of the latter 2 options. The demand for new therapeutic options, combined with greater insight into basic immunobiology, has led to the emergence of novel approaches to treat Graves' hyperthyroidism. The current therapies under investigation include biologics, small molecules, and peptide immunomodulation. There is a growing focus on TSHR-specific treatment modalities, which carry the advantage of eliciting a specific, targeted approach, with the aim of avoiding disruption of the functioning immune system. These therapies present a new opportunity to supersede the inadequate treatments currently available for some Graves' patients, offering hope of successful restoration of euthyroidism without the need for ongoing therapy. Several of these therapeutic options have the potential to translate into clinical practice in the near future. This review provides a comprehensive summary of the recent advances and various stages of development of the novel therapeutic approaches to treat Graves' hyperthyroidism.


Asunto(s)
Terapia Biológica , Enfermedad de Graves/terapia , Receptores de Tirotropina , Terapia Biológica/métodos , Humanos , Receptores de Tirotropina/efectos de los fármacos
2.
Mol Biol Rep ; 47(4): 2801-2810, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32242301

RESUMEN

Untreated hyperthyroidism may develop serious complications. This attempt was made to investigate the potential of Aloe vera gel in regulating experimentally induced hyperthyroidism in rats. Female Wistar rats were made hyperthyroid with L-thyroxine (L-T4) at 0.5 mg/kg/day, i.p. for 14 days and the effects of Aloe vera methanolic fraction (AVMF) (50 or 500 mg/kg/day, p.o.,) and a conventional antithyroid drug propylthiouracil (PTU) (10 mg/kg, i.p.) for 30 days were studied in those hyperthyroid rats. At the end, alterations in serum thyroid hormones and thyroid stimulating hormone (TSH); hepatic 5'mono-deiodinase-1(5'D1) activity, oxidative stress markers and antioxidants; serum inflammatory cytokines and the expression of thyrotropin receptor in thyroid gland were evaluated in all experimental animals. Hyperthyroid condition was confirmed by an increase in thyroid hormone levels and hepatic 5'D-1 activity with a decrease in TSH. However, either AVMF or PTU treatment in hyperthyroid rats decreased the levels of thyroid hormones and 5'D1 activity. AVMF administration in T4-induced rats also decreased the oxidative stress markers such as thiobarbituric acid reactive substances and lipid hydroperoxides and increased the antioxidant levels in liver tissues. Levels of liver marker enzymes, cytokines and different lipids were decreased in T4-induced AVMF treated rats. Further, a down regulation in the TSHR expression in thyroid was observed in AVMF or PTU treated groups. All these thyroid inhibiting effects were supported by an improvement in thyroid histology in hyperthyroid rats. It appears, about 15 compounds, as evidenced by LC-MS/MS study, mostly phenolics are involved in this anti-thyroid effects of the test compound.


Asunto(s)
Aloe/metabolismo , Hipertiroidismo/tratamiento farmacológico , Receptores de Tirotropina/efectos de los fármacos , Animales , Cromatografía Liquida/métodos , Femenino , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Hígado/metabolismo , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Propiltiouracilo/farmacología , Ratas , Ratas Wistar , Receptores de Tirotropina/metabolismo , Espectrometría de Masas en Tándem/métodos , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/metabolismo , Hormonas Tiroideas/metabolismo , Tirotropina/sangre , Tirotropina/farmacología , Tiroxina/efectos adversos
3.
Endocrinol Metab (Seoul) ; 34(1): 29-38, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30912336

RESUMEN

Whether or not Graves' hyperthyroidism can be really cured, depends on the definition of "cure." If eradication of thyroid hormone excess suffices for the label "cure," then all patients can be cured because total thyroidectomy or high doses of ¹³¹I will abolish hyperthyroidism albeit at the expense of creating another disease (hypothyroidism) requiring lifelong medication with levothyroxine. I would not call this a "cure," which I would like to define as a state with stable thyroid stimulating hormone (TSH), free thyroxine, and triiodothyronine serum concentrations in the normal range in the absence of any thyroid medication. Surgery and radioiodine are unlikely to result in so-defined cures, as their preferable aim as stated in guidelines is to cause permanent hypothyroidism. Discontinuation of antithyroid drugs is followed by 50% recurrences within 4 years; before starting therapy the risk of recurrences can be estimated with the Graves' Recurrent Events After Therapy (GREAT) score. At 20-year follow-up about 62% had developed recurrent hyperthyroidism, 8% had subclinical hypothyroidism, and 3% overt hypothyroidism related to TSH receptor blocking antibodies and thyroid peroxidase antibodies. Only 27% was in remission, and might be considered cured. If the definition of "cure" would also include the disappearance of thyroid antibodies in serum, the proportion of cured patients would become even lower.


Asunto(s)
Enfermedad de Graves/radioterapia , Enfermedad de Graves/cirugía , Hipertiroidismo/radioterapia , Hipertiroidismo/cirugía , Adulto , Antitiroideos/efectos adversos , Antitiroideos/uso terapéutico , Femenino , Estudios de Seguimiento , Enfermedad de Graves/complicaciones , Enfermedad de Graves/tratamiento farmacológico , Humanos , Hipertiroidismo/tratamiento farmacológico , Hipertiroidismo/epidemiología , Hipotiroidismo/tratamiento farmacológico , Hipotiroidismo/etiología , Yoduro Peroxidasa/inmunología , Radioisótopos de Yodo/uso terapéutico , Masculino , Persona de Mediana Edad , Guías de Práctica Clínica como Asunto , Receptores de Tirotropina/efectos de los fármacos , Receptores de Tirotropina/inmunología , Recurrencia , Riesgo , Hormonas Tiroideas/sangre , Tiroidectomía/efectos adversos , Tirotropina/sangre , Tiroxina/uso terapéutico , Resultado del Tratamiento , Triyodotironina/sangre
4.
Drug Chem Toxicol ; 41(4): 501-508, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29143548

RESUMEN

Thyroid hormones are involved in many important physiological activities including regulation of energy metabolism, development of nervous system, maintenance of cerebral functions, and so on. Endocrine-disrupting chemicals (EDCs) that interfere with thyroid functions raise serious concerns due to their frequent misuse in areas where regulations are poorly implemented. In addition, chemicals that are originally regarded safe may now be considered as toxic with the development of life sciences. Malathion is an organophosphate insecticide that is widely applied and distributed in agricultural and residential settings. Due to the low acute toxicity and rapid degradation, malathion is not listed as a primary thyroid disrupting chemical. However, emerging evidences reported that malathion affected thyroperoxidase catalyzed iodide oxidation which in turn influenced thyroid hormone transportation, and enhanced parathyroid hyperplasia prevalence. Nevertheless, direct effect of malathion on thyroid hormone biosynthesis remains to be elucidated. This study investigated the effects of thyroid disruption of malathion in Fischer rat thyroid follicular cell line, FRTL-5. Transcriptional and translational analyses on thyroglobulin demonstrated that both mRNA and protein expression levels were significantly inhibited by malathion. Cellular cAMP level and TSH receptor expression were distinctly reduced by malathion (6.0 µg/ml). These results suggested that malathion directly disrupted the biosynthesis of thyroid hormone and the mechanism involved down-regulation of TSH receptor and cellular cAMP. This subsequently led to the suppression of TSH dependent signal transduction, TG transcription inhibition, and obstruction of thyroid hormone biosynthesis.


Asunto(s)
Disruptores Endocrinos/toxicidad , Malatión/toxicidad , Células Epiteliales Tiroideas/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , AMP Cíclico/análisis , Ratas , Ratas Endogámicas F344 , Receptores de Tirotropina/efectos de los fármacos , Tiroglobulina/genética
5.
Thyroid ; 27(2): 292-299, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27829313

RESUMEN

OBJECTIVE: The differentiation program for human thyroid follicular cells (TFCs) relies on the interplay between sequence-specific transcription factors and transcriptional co-regulators. Transcriptional co-activator with PDZ-binding motif (TAZ) is a co-activator that regulates several transcription factors, including PAX8 and NKX2-1, which play a central role in thyroid-specific gene transcription. TAZ and PAX8/NKX2-1 are co-expressed in the nuclei of thyroid cells, and TAZ interacts directly with both PAX8 and NKX2-1, leading to their enhanced transcriptional activity on the thyroglobulin (TG) promoter and additional genes. METHODS: The use of a small molecule, ethacridine, recently identified as a TAZ activator, in the differentiation of thyroid cells from human embryonic stem (hES) cells was studied. First, endodermal cells were derived from hES cells using Activin A, followed by induction of differentiation into thyroid cells directed by ethacridine and thyrotropin (TSH). RESULTS: The expression of TAZ was increased in the Activin A-derived endodermal cells by ethacridine in a dose-dependent manner and followed by increases in PAX8 and NKX2-1 when assessed by both quantitative polymerase chain reaction and immunostaining. Following further differentiation with the combination of ethacridine and TSH, the thyroid-specific genes TG, TPO, TSHR, and NIS were all induced in the differentiated hES cells. When these cells were cultured with extracellular matrix-coated dishes, thyroid follicle formation and abundant TG protein expression were observed. Furthermore, such hES cell-derived thyroid follicles showed a marked TSH-induced and dose-dependent increase in radioiodine uptake and protein-bound iodine accumulation. CONCLUSION: These data show that fully functional human thyroid cells can be derived from hES cells using ethacridine, a TAZ activator, which induces thyroid-specific gene expression and promotes thyroid cell differentiation from the hES cells. These studies again demonstrate the importance of transcriptional regulation in thyroid cell development. This approach also yields functional human thyrocytes, without any gene transfection or complex culture conditions, by directly manipulating the transcriptional machinery without interfering with intermediate signaling events.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Etacridina/farmacología , Células Madre Embrionarias Humanas/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular/efectos de los fármacos , Células Epiteliales Tiroideas/efectos de los fármacos , Tirotropina/farmacología , Activinas/farmacología , Autoantígenos/efectos de los fármacos , Autoantígenos/genética , Diferenciación Celular/genética , Células Madre Embrionarias Humanas/citología , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Yoduro Peroxidasa/efectos de los fármacos , Yoduro Peroxidasa/genética , Proteínas de Unión a Hierro/efectos de los fármacos , Proteínas de Unión a Hierro/genética , Factor de Transcripción PAX8/efectos de los fármacos , Factor de Transcripción PAX8/genética , Receptores de Tirotropina/efectos de los fármacos , Receptores de Tirotropina/genética , Simportadores/efectos de los fármacos , Simportadores/genética , Tiroglobulina/efectos de los fármacos , Tiroglobulina/genética , Células Epiteliales Tiroideas/citología , Factor Nuclear Tiroideo 1/efectos de los fármacos , Factor Nuclear Tiroideo 1/genética , Transactivadores , Factores de Transcripción , Proteínas Coactivadoras Transcripcionales con Motivo de Unión a PDZ
6.
J Clin Endocrinol Metab ; 101(1): 114-22, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26502358

RESUMEN

CONTEXT: Graves' orbitopathy (GO) is a disfiguring/distressing, inflammatory autoimmune condition. This intractable problem is caused by expansion of the orbital contents around the eye by excessive fat generation (adipogenesis) and overproduction of extracellular matrix components, especially hyaluronan (HA) from preadipocytes/fibroblasts (PFs). Current immunosuppressive/antiinflammatory treatments are largely ineffective and have unpleasant side effects, and a better therapeutic strategy through understanding GO-associated pathological features is needed. OBJECTIVE: Previously we identified depot-specific HA synthase 2 regulation (HAS2; major source of HA), which facilitates orbit-specific HA accumulation during adipogenesis, and targeting phosphatidylinositol-3-kinase/mechanistic target of rapamycin-complex-1 pathways blocked both pathological features. The current study revealed low expression levels of Forkhead box O (FOXOs; critical downstream effectors of phosphatidylinositol-3-kinase) in orbital PFs through adipogenesis compared with sc levels. We aimed to dissect the role of FOXOs in GO pathogenesis to identify nonimmunosuppressive targets for GO treatment. DESIGN/SETTING/PARTICIPANTS: Human orbital and sc primary PFs were treated with small interfering RNA/chemical inhibitor (AS1842856) of FOXOs or FOXO enhancer trifluoperazine hydrochloride (TFP; Food and Drug Administration approved drug), in serum-free medium for 24 hours, or TFP treatment in adipogenic medium for 15 days. MAIN OUTCOME MEASURES: Quantitative PCR was used to measure HAS2 transcripts and the terminal adipogenesis differentiation marker lipoprotein lipase. HA accumulation in the medium was measured by an ELISA. RESULTS: Substantially increased or decreased HAS2/HA production was observed by inhibiting (small interfering RNA or chemical inhibitor) or enhancing (TFP) FOXO expression, respectively. TFP treatment is also sufficient to counteract thyrotropin receptor-activated HAS2/HA production and block adipogenesis in orbital PFs. CONCLUSIONS: FOXOs play a crucial repressor role in the regulation of HAS2/HA production and adipogenesis in orbital PFs. Our data reveal for the first time that resetting GO-associated pathological features through drug-targeted activation of FOXOs could provide a feasible nonimmunosuppressive therapeutic strategy for GO.


Asunto(s)
Factores de Transcripción Forkhead/genética , Oftalmopatía de Graves/genética , Oftalmopatía de Graves/patología , Adipogénesis/efectos de los fármacos , Adipogénesis/genética , Adulto , Femenino , Glucuronosiltransferasa/genética , Humanos , Hialuronano Sintasas , Ácido Hialurónico/metabolismo , Técnicas In Vitro , Persona de Mediana Edad , Fosfatidilinositol 3-Quinasa/genética , Quinolonas/uso terapéutico , ARN Interferente Pequeño/antagonistas & inhibidores , Receptores de Tirotropina/efectos de los fármacos , Grasa Subcutánea/metabolismo , Activación Transcripcional , Trifluoperazina/farmacología
7.
PLoS One ; 10(12): e0144426, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26658480

RESUMEN

High-throughput screening (HTS) experiments provide a valuable resource that reports biological activity of numerous chemical compounds relative to their molecular targets. Building computational models that accurately predict such activity status (active vs. inactive) in specific assays is a challenging task given the large volume of data and frequently small proportion of active compounds relative to the inactive ones. We developed a method, DRAMOTE, to predict activity status of chemical compounds in HTP activity assays. For a class of HTP assays, our method achieves considerably better results than the current state-of-the-art-solutions. We achieved this by modification of a minority oversampling technique. To demonstrate that DRAMOTE is performing better than the other methods, we performed a comprehensive comparison analysis with several other methods and evaluated them on data from 11 PubChem assays through 1,350 experiments that involved approximately 500,000 interactions between chemicals and their target proteins. As an example of potential use, we applied DRAMOTE to develop robust models for predicting FDA approved drugs that have high probability to interact with the thyroid stimulating hormone receptor (TSHR) in humans. Our findings are further partially and indirectly supported by 3D docking results and literature information. The results based on approximately 500,000 interactions suggest that DRAMOTE has performed the best and that it can be used for developing robust virtual screening models. The datasets and implementation of all solutions are available as a MATLAB toolbox online at www.cbrc.kaust.edu.sa/dramote and can be found on Figshare.


Asunto(s)
Ensayos Analíticos de Alto Rendimiento/métodos , Bases de Datos de Compuestos Químicos , Humanos , Receptores de Tirotropina/efectos de los fármacos
8.
J UOEH ; 36(4): 277-83, 2014 Dec 01.
Artículo en Japonés | MEDLINE | ID: mdl-25501760

RESUMEN

We report a case of apathetic hyperthyroidism associated with unrecognized slowly growing functional thyroid adenoma (Plummer's disease), atrial fibrillation and heart failure. An 81-year-old woman with worsening thyroid dysfunction was admitted to our hospital for the treatment of heart failure. The patient had developed heart failure associated with chronic atrial fibrillation at 76 years of age, and one year later was found to have asymptomatic hyperthyroidism. Anti-thyroid autoantibodies were negative, but thyroid echography showed a 32-mm tumor devoid of internal blood flow in the left lower lobe. Free thyroxine 4 (FT4) decreased from 3.30 to 2.60 ng/dl without treatment. The patient was diagnosed with transient thyroiditis and was followed-up without treatment. However, a repeat thyroid echography showed growth of the tumor to 41 mm in 4 years. Thyroid scintigraphy showed uptake that matched the thyroid mass. Based on these findings, the established diagnosis was Plummer's disease complicated with heart failure. The patient was treated with anti-thyroid drugs, which resulted in improvement of FT4 and reduced the severity of heart failure. In this rare case of an elderly patient, Plummer's disease was associated with a slowly-growing functional thyroid adenoma, apathetic hyperthyroidism, repeated episodes of atrial fibrillation and heart failure. Since symptoms of thyrotoxicosis are likely to be missed in the elderly, it is necessary to include hyperthyroidism in the pathoetiology of heart failure and atrial fibrillation in this population.


Asunto(s)
Bocio Nodular/complicaciones , Insuficiencia Cardíaca/etiología , Hipertiroidismo/etiología , Receptores de Tirotropina/deficiencia , Tirotoxicosis/complicaciones , Anciano de 80 o más Años , Antitiroideos/administración & dosificación , Antitiroideos/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/etiología , Femenino , Bocio Nodular/diagnóstico , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Hipertiroidismo/diagnóstico , Hipertiroidismo/tratamiento farmacológico , Metimazol/administración & dosificación , Metimazol/uso terapéutico , Receptores de Tirotropina/efectos de los fármacos , Recurrencia , Tirotoxicosis/diagnóstico , Resultado del Tratamiento
9.
Curr Opin Endocrinol Diabetes Obes ; 21(5): 415-21, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25111942

RESUMEN

PURPOSE OF REVIEW: In most patients with hyperthyroidism caused by Graves' disease, antithyroid drug (ATD) therapy is followed by a gradual amelioration of the autoimmune abnormality, but about half of the patients will experience relapse of hyperthyroidism when the ATDs are withdrawn after a standard 1 to 2 years of therapy. This is a major drawback of ATD therapy, and a major concern to patients. We review current knowledge on how to predict and possibly reduce the risk of such relapse. RECENT FINDINGS: Several patient and disease characteristics, as well as environmental factors and duration of ATD therapy, may influence the risk of relapse after ATD withdrawal. Depending on the presence of such factors, the risk of relapse after ATD withdrawal may vary from around 10 to 90%. Risk factors for relapse should be taken into account when choosing between therapeutic modalities in a patient with newly diagnosed disease, and also when discussing duration of ATD therapy. SUMMARY: Prolonged low-dose ATD therapy may be feasible in patients with high risk of relapse, such as children and patients with active Graves' orbitopathy, and in patients with previous relapse who prefer such therapy rather than surgery or radioiodine.


Asunto(s)
Antitiroideos/administración & dosificación , Enfermedad de Graves/tratamiento farmacológico , Metimazol/administración & dosificación , Receptores de Tirotropina/efectos de los fármacos , Esquema de Medicación , Enfermedad de Graves/inmunología , Enfermedad de Graves/patología , Humanos , Receptores de Tirotropina/inmunología , Recurrencia , Factores de Riesgo , Fumar/efectos adversos , Fumar/inmunología , Factores de Tiempo , Resultado del Tratamiento
10.
Ginekol Pol ; 85(6): 472-5, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25029815

RESUMEN

Thyroid disorders, both in women who wish to conceive and in gravidas, has become a topic of much interest to numerous researchers. Ovarian hyperstimulation syndrome (OHSS) is a potentially life-threatening condition among women undergoing controlled ovarian hyperstimulation (COH). We present a case of thyroid dysfunction in severe OHSS in a patient diagnosed with subclinical hypothyroidism before COH. The dose of L-thyroxine (L-T4) was increased before the procedure in order to reach TSH levels below 2.5 mU/L, and from day 1 of the stimulation the dose of L-T4 was increased by 33%. The patient remained clinically and biochemically euthyroid until day 8 after the embriotransfer (ET). Then, the woman developed severe OHSS, with fluid in the pleural and peritoneal cavity and laboratory evidence of severe OHSS. Laboratory thyroid function tests revealed overt hypothyroidism. L-T4 dose was not increased due to serious clinical condition of the patient. Iodine supplementation was initiated instead. After the symptoms subsided, a period of clinical and laboratory euthyroid state was observed, followed by gestational hyperthyroidism. The L-T4 dose was reduced and iodine supplementation was temporarily ceased. The thyroid function stabilized, while maintaining the L-T4 and iodine supplementation, at 20 weeks of gestation. The patient gave birth by a caesarean section at 37 weeks of gestation and returned to the pre-pregnancy dose of L-T4. To the best of our knowledge, this has been the first report about a patient with thyroid dysfunction in severe OHSS in the Polish literature. On the basis of the presented case and a review of the literature on thyroid dysfunction in women undergoing COH and OHSS, we conclude that clinical signs and biochemical parameters need to be taken into consideration while making therapeutic decision in women with thyroid dysfunction in the course of OHSS. Also, further studies are necessary to elucidate the matter.


Asunto(s)
Hipertiroidismo/etiología , Síndrome de Hiperestimulación Ovárica/etiología , Inducción de la Ovulación/efectos adversos , Complicaciones del Embarazo/etiología , Receptores de Tirotropina/deficiencia , Adulto , Femenino , Humanos , Hipotiroidismo/complicaciones , Hipotiroidismo/tratamiento farmacológico , Yodo/uso terapéutico , Polonia , Embarazo , Receptores de Tirotropina/efectos de los fármacos , Glándula Tiroides/metabolismo , Tiroxina/uso terapéutico
11.
Menopause ; 19(11): 1253-9, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22713859

RESUMEN

OBJECTIVE: 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 THRß1 in the uterus of surgically menopausal monkeys. METHODS: 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. RESULTS: 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 THRß 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. CONCLUSIONS: 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.


Asunto(s)
Hormonas Esteroides Gonadales/farmacología , Macaca fascicularis , Receptores de Hormona Tiroidea/efectos de los fármacos , Receptores de Hormona Liberadora de Tirotropina/efectos de los fármacos , Receptores de Tirotropina/efectos de los fármacos , Útero/química , Animales , Estrógenos Conjugados (USP)/administración & dosificación , Femenino , Inmunohistoquímica/veterinaria , Acetato de Medroxiprogesterona/administración & dosificación , Norpregnenos/administración & dosificación , Receptores de Hormona Tiroidea/análisis , Receptores de Tirotropina/análisis , Receptores de Hormona Liberadora de Tirotropina/análisis , Receptores alfa de Hormona Tiroidea/análisis , Receptores alfa de Hormona Tiroidea/efectos de los fármacos , Receptores beta de Hormona Tiroidea/análisis , Receptores beta de Hormona Tiroidea/efectos de los fármacos , Útero/fisiología
12.
Thyroid ; 21(7): 783-92, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21568725

RESUMEN

BACKGROUND: Superagonist analogs of human thyroid-stimulating hormone (hTSH) may stimulate the uptake of (131)I-iodide and (18)F-fluorodeoxyglucose ((18)F-FDG) in thyroid carcinomas to a greater degree than hTSH. We herein report the potency and efficacy of two hTSH analogs, TR1401 and TR1402, to stimulate radioiodide and (18)F-FDG uptake in FRTL-5 cells and compared the effects of hTSH and TR1401 on radioiodide uptake in the thyroid in vivo in mice. METHODS: The effects of hTSH analogs on intracellular levels of cAMP, uptake of (131)I-iodide, and (18)F-FDG were studied in FRTL-5 cells to determine the stimulatory potency and efficacy of the compounds by calculating half-maximum effective concentration (EC(50)) values and maximal stimulatory effects (E(max)). Biodistribution studies (n = 96) and positron emission tomography/computed tomography imaging studies (single animals) on thyroid (125)I/(124)I-iodide uptake were performed with T3-suppressed CD-1 mice in a dose-dependent manner (3, 10, and 30 µg/animal). RESULTS: The EC(50) values of TR1401 and TR1402 demonstrated a 90-fold or 800-fold higher potency for their capacity to increase intracellular cAMP levels in comparison with hTSH (p < 0.05). Similar results were demonstrated for the stimulation of (18)F-FDG uptake. Bovine TSH, TR1401, and TR1402 were 85%-490% more potent to increase iodide uptake than hTSH (p < 0.05). TR1402 was 30% more efficacious to stimulate iodide uptake than hTSH. The agonist-induced increase in radiotracer uptake was paralleled by increases in NIS and GLUT-1 expression. Ex vivo biodistribution studies showed an increased iodide uptake in the thyroid of TR1401-treated mice at the low dose of 3 µg/animal in comparison with hTSH-treated mice (n = 16, p < 0.05). Positron emission tomography/computed tomography imaging studies confirmed the increased thyroidal iodide uptake in TR1401-treated mice in vivo. CONCLUSIONS: TR1401 and TR1402 have considerably higher potency than hTSH to stimulate thyroidal iodide and (18)F-FDG uptake in vitro. Moreover, in vivo studies indicated that at low but not higher doses, TR1401 induced an enhanced ability for the thyroid to concentrate iodide compared with hTSH. These properties makes TR1401 and TR1402 interesting candidates for use in humans to enhance uptake of radioiodine and (18)F-FDG by metastases and recurrences of thyroid carcinoma.


Asunto(s)
Radioisótopos de Yodo , Glándula Tiroides/metabolismo , Tirotropina/análogos & derivados , Tirotropina/agonistas , Animales , Línea Celular , AMP Cíclico/metabolismo , Femenino , Fluorodesoxiglucosa F18 , Humanos , Ratones , Ratas , Receptores de Tirotropina/efectos de los fármacos , Receptores de Tirotropina/metabolismo , Yoduro de Sodio/metabolismo , Tirotropina/farmacología , Distribución Tisular
13.
Toxicol Appl Pharmacol ; 253(2): 121-9, 2011 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-21466821

RESUMEN

DDT is a highly lipophilic molecule known to deplete membrane rafts of their phosphoglycolipid and cholesterol contents. However, we have recently shown that DDT can also alter the thyroid homeostasis by inhibiting TSH receptor (TSHr) internalization. The present study was undertaken to verify whether DDT goitrogenic effects are due to the insecticide acting directly on TSHr or via alteration of the membrane rafts hosting the receptor itself. Our results demonstrate that, in CHO-TSHr transfected cells, TSHr is activated in the presence of TSH, while it is inhibited following DDT exposure. DDT can also reduce the endocytic vesicular traffic, alter the extension of multi-branched microvilli along their plasma membranes and induce TSHr shedding in vesicular forms. To verify whether TSHr displacement might depend on DDT altering the raft constitution of CHO-TSHr cell membranes the extent of TSHr and lipid raft co-localization was examined by confocal microscopy. Evidence shows that receptor/raft co-localization increased significantly upon exposure to TSH, while receptors and lipid rafts become dislodged on opposite cell poles in DDT-exposed CHO-TSHr cells. As a control, under similar culturing conditions, diphenylethylene, which is known to be a lipophilic substance that is structurally related to DDT, did not affect the extent of TSHr and lipid raft co-localization in CHO-TSHr cells treated with TSH. These findings corroborate and extend our view that, in CHO cells, the DDT disrupting action on TSHr is primarily due to the insecticide acting on membranes to deplete their raft cholesterol content, and that the resulting inhibition on TSHr internalization is due to receptor dislodgement from altered raft microdomains of the plasma membrane.


Asunto(s)
DDT/toxicidad , Insecticidas/toxicidad , Microdominios de Membrana/efectos de los fármacos , Receptores de Tirotropina/efectos de los fármacos , Animales , Células CHO , Cricetinae , Cricetulus , Receptores de Tirotropina/genética , Receptores de Tirotropina/metabolismo
14.
FASEB J ; 24(2): 393-403, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19825978

RESUMEN

Thyrotropin-releasing hormone (TRH) is the most proximal component of the hypothalamic-pituitary-thyroid axis that regulates thyroid hormone synthesis. Since transcripts for members of this axis were detected in cultured normal human skin cells and since human hair follicles (HFs) respond to stimulation with thyrotropin, we now have studied whether human HF functions are also modulated by TRH. Here we report that the epithelium of normal human scalp HFs expresses not only TRH receptors (TRH-R) but also TRH itself at the gene and protein level. Stimulation of microdissected, organ-cultured HFs with TRH promotes hair-shaft elongation, prolongs the hair cycle growth phase (anagen), and antagonizes its termination by TGF-beta2. It also increases proliferation and inhibits apoptosis of hair matrix keratinocytes. These TRH effects may be mediated in part by reducing the ATM/Atr-dependent phosphorylation of p53. By microarray analysis, several differentially up- or down-regulated TRH-target genes were detected (e.g., selected keratins). Thus, human scalp HFs are both a source and a target of TRH, which operates as a potent hair-growth stimulator. Human HFs provide an excellent discovery tool for identifying and dissecting nonclassical functions of TRH and TRH-mediated signaling in situ, which emerge as novel players in human epithelial biology.


Asunto(s)
Cabello/crecimiento & desarrollo , Hormona Liberadora de Tirotropina/fisiología , Apoptosis , Femenino , Regulación de la Expresión Génica , Folículo Piloso/efectos de los fármacos , Folículo Piloso/crecimiento & desarrollo , Humanos , Queratinocitos/citología , Persona de Mediana Edad , Técnicas de Cultivo de Órganos , Receptores de Tirotropina/efectos de los fármacos , Receptores de Tirotropina/metabolismo
17.
Thyroid ; 18(6): 631-5, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18578612

RESUMEN

BACKGROUND: Sunitinib, a multitargeted vascular endothelial growth factor and receptor tyrosine kinase inhibitor, causes hypothyroidism in patients who take it for treatment of cancer. Although the pathophysiologic mechanism of the hypothyroidism is unclear, it has been claimed that it is due to inhibition of iodide uptake. METHODS: To evaluate the pathologic mechanism of induction of the hypothyroidism, we studied the effect of sunitinib on FRTL-5 rat thyroid cells. We measured the effect of sunitinib on cell growth, (125)I-iodide uptake and efflux, TSH receptor (TSH-R), and sodium-iodide symporter (NIS) message. RESULTS: At 48 hours, sunitinib caused a dose-related inhibition of growth with LC(50) of 14.6 muM, but there was no apparent inhibition of growth at 24 hours at concentrations of 0.1-25 microM. Preincubation with sunitinib did not impair the response to TSH, indicating that it did not affect the TSH-R. Incubation with sunitinib for 24 hours caused a dose-related increase of (125)I-iodide uptake and did not reduce iodide efflux or NIS mRNA expression. CONCLUSION: The data indicate that sunitinib is unlikely to cause hypothyroidism by inhibition of iodide uptake.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Indoles/farmacología , Pirroles/farmacología , Glándula Tiroides/crecimiento & desarrollo , Animales , Transporte Biológico/efectos de los fármacos , Línea Celular , Relación Dosis-Respuesta a Droga , Radioisótopos de Yodo/farmacocinética , ARN Mensajero/metabolismo , Ratas , Receptores de Tirotropina/efectos de los fármacos , Receptores de Tirotropina/metabolismo , Sunitinib , Simportadores/metabolismo , Glándula Tiroides/citología , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/metabolismo , Factores de Tiempo
18.
Mini Rev Med Chem ; 8(1): 91-6, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18220988

RESUMEN

Thyroid stimulating hormone (TSH; also known as thyrotropin), binds cognate receptors on the surface of thyrocytes to regulate proliferation and thyroid hormone synthesis. This unidimensional view of TSH is being transformed as new evidence indicates that TSH acts on adipose tissue. Adipocyte inflammatory responses that predispose to cardiovascular disease may occur in thyroid disorders associated with elevated TSH levels.


Asunto(s)
Adipocitos/metabolismo , Receptores de Tirotropina/metabolismo , Tirotropina/fisiología , Adipocitos/efectos de los fármacos , Animales , Enfermedades Cardiovasculares/etiología , Humanos , Hipotiroidismo/complicaciones , Hipotiroidismo/metabolismo , Inflamación/metabolismo , Interleucina-6/metabolismo , Receptores de Tirotropina/efectos de los fármacos , Factores de Riesgo , Tirotropina/farmacología
19.
J Pak Med Assoc ; 55(8): 321-4, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16164157

RESUMEN

OBJECTIVE: To determine the progesterone receptor status in thyroid gland. METHODS: This study was based on immunohistochemical staining of formalin fixed paraffin embedded tissues, for progesterone receptors, in 50 previously diagnosed cases of various thyroid lesions and surrounding normal thyroid tissue. RESULTS: Out of 50 cases, 8 were nodular goiter, 9 cases of adenoma, 19 papillary carcinoma, 10 follicular carcinoma and four cases were of medullary carcinoma. Surrounding normal tissue was available in 4 non-neoplastic and 21 neoplastic lesions. Overall male patients comprised 20% (10 cases) and females 80% (40 cases). Although a wide range of lesions in both the sexes including wide age range were available, none of our cases were positively stained for progesterone receptors. CONCLUSION: In contrary to earlier reports by immunohistochemical method using monoclonal mouse anti-PR antibody clone PgR 636, on formalin-fixed paraffin embedded thyroid tissues, the progesterone receptors were not detectable in our human samples. The effect of progesterone on thyroid gland may be an indirect one.


Asunto(s)
Receptores de Progesterona/inmunología , Glándula Tiroides/inmunología , Neoplasias de la Tiroides/inmunología , Adolescente , Adulto , Factores de Edad , Anticuerpos Monoclonales , Colorantes , Femenino , Bocio Nodular/inmunología , Bocio Nodular/patología , Humanos , Inmunohistoquímica , Indicadores y Reactivos , Masculino , Persona de Mediana Edad , Receptores de Progesterona/efectos de los fármacos , Receptores de Tirotropina/efectos de los fármacos , Receptores de Tirotropina/inmunología , Factores Sexuales , Glándula Tiroides/patología , Neoplasias de la Tiroides/patología
20.
Presse Med ; 34(2 Pt 1): 94-100, 2005 Jan 29.
Artículo en Francés | MEDLINE | ID: mdl-15687976

RESUMEN

INTRODUCTION: In order to evaluate the efficacy of 131 Iodine on goitre volume and on thyroid function, we studied a cohort of patients exhibiting a multinodular and toxic or non toxic goitre. METHODS: This retrospective study was conducted at the Marc Linquette clinic in Lille, in collaboration with the department of nuclear medicine. Thirty-eight patients treated with 131 Iodine were included from 1995 to 2001. Clinical examination and serum analyses including TSH, free T4 and T3, anti-thyroid peroxidase and anti-thyroglobulin antibodies and TSH-receptor antibodies measurements were conducted on inclusion and then at 3, 6, 12 and 72 months. The activity of 131 Iodine corresponded to a standard dose or was calculated according to Marinelli's method. We excluded patients who had not undergone assessment at the above-mentioned time schedules. RESULTS: The treatment was indicated in 30 patients presenting with a non compressive but toxic goitre, in 5 patients with a toxic compressive goitre and in 3 patients with a compressive but non-toxic goitre. Surgery had been excluded for all these patients because of their age, their cardiac status or because they had refused surgery after failure with prior partial thyroidectomy or medical treatment. Among the toxic goitres, TSH levels were low and T3 and T4 increased in 17 patients. In the 18 others, hyperthyroidism was manifested by an isolated decrease of TSH. The thyroid volume before treatment, assessed in 20 patients, was of 18 to 135 cm3 (mean: 53 cm3). Treatment consisted in administration of radioactivity of 3 to 30 mCi in 30 patients and standard activity of 20 to 25 mCi in 8. Functional efficacy with reduction in hyperthyroidism was noted after 3 months, and corrected in nearly all patients after 1 year, and morphological efficacy, with a mean decrease of 33.5% in the size of the goitres. No supplementary surgery was required, notably for the initially compressed goitres. Immediate and long term tolerance was satisfactory. CONCLUSION: Metabolic 131Iodine radiotherapy is effective for the functional and morphological treatment of goitres with good tolerance and few side effects. 131 Iodine is a reasonable alternative in cases with absolute or relative contraindication for surgery.


Asunto(s)
Bocio/tratamiento farmacológico , Radioisótopos de Yodo/uso terapéutico , Anciano , Anciano de 80 o más Años , Autoanticuerpos/sangre , Autoanticuerpos/efectos de los fármacos , Monitoreo de Drogas , Utilización de Medicamentos , Femenino , Bocio/sangre , Bocio/diagnóstico , Humanos , Inmunoglobulinas Estimulantes de la Tiroides , Inflamación , Yoduro Peroxidasa/antagonistas & inhibidores , Radioisótopos de Yodo/farmacología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tamaño de los Órganos/efectos de los fármacos , Selección de Paciente , Guías de Práctica Clínica como Asunto , Receptores de Tirotropina/sangre , Receptores de Tirotropina/efectos de los fármacos , Estudios Retrospectivos , Pruebas de Función de la Tiroides , Tirotropina/sangre , Tirotropina/efectos de los fármacos , Tiroxina/sangre , Tiroxina/efectos de los fármacos , Resultado del Tratamiento , Triyodotironina/sangre , Triyodotironina/efectos de los fármacos
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