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PURPOSE: The use of thyroid hormones (TH) to treat obesity is unsupported by evidence as reflected in international guidelines. We explored views about this practice, and associations with respondent characteristics among European thyroid specialists. METHODS: Specialists from 28 countries were invited to a survey via professional organisations. The relevant question was whether "Thyroid hormones may be indicated in biochemically euthyroid patients with obesity resistant to lifestyle interventions". RESULTS: Of 17,232 invitations 5695 responses were received (33% valid response rate; 65% women; 90% endocrinologists). Of these, 290 (5.1%) stated that TH may be indicated as treatment for obesity in euthyroid patients. This view was commoner among non-endocrinologists (8.7% vs. 4.7%, p < 0.01), private practice (6.5% vs. 4.5%, p < 0.01), and varied geographically (Eastern Europe, 7.3%; Southern Europe, 4.8%; Western Europe, 2.7%; and Northern Europe, 2.5%). Respondents from Northern and Western Europe were less likely to use TH than those from Eastern Europe (p < 0.01). Gross national income (GNI) correlated inversely with this view (OR 0.97, CI: 0.96-0.97; p < 0.001). Having national guidelines on hypothyroidism correlated negatively with treating obesity with TH (OR 0.71, CI: 0.55-0.91). CONCLUSIONS: Despite the lack of evidence, and contrary to guidelines' recommendations, about 5% of respondents stated that TH may be indicated as a treatment for obesity in euthyroid patients resistant to life-style interventions. This opinion was associated with (i) respondent characteristics: being non-endocrinologist, working in private practice, treating a small number of hypothyroid patients annually and (ii) national characteristics: prevalence of obesity, Eastern Europe, low GNI and lack of national hypothyroidism guidelines.
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BACKGROUND: Smoking is a strong risk factor for the development of Graves' ophthalmopathy (GO). Immediate early genes (IEGs) are overexpressed in patients with active GO compared to healthy controls. The aim of this study was to study the effects of tobacco smoking and simvastatin on preadipocytes and orbital fibroblasts (OFs) in the adipogenic process. METHODS: Cigarette smoke extract (CSE) was generated by a validated pump system. Mouse 3T3-L1 preadipocytes or OFs were exposed to 10% CSE with or without simvastatin. Gene expression was studied in preadipocytes and OFs exposed to CSE with or without simvastatin and compared to unexposed cells or cells treated with a differentiation cocktail. RESULTS: In 3T3-L1 preadipocytes, Cyr61, Ptgs2, Egr1 and Zfp36 expression levels were two-fold higher in cells exposed to CSE than in unexposed cells. Simvastatin downregulated the expression of these genes (1.6-fold, 5.5-fold, 3.3-fold, 1.4-fold, respectively). CSE alone could not stimulate preadipocytes to differentiate. Scd1, Ppar-γ and adipogenesis were downregulated in simvastatin-treated preadipocytes compared to nontreated preadipocytes 18-, 35- and 1.7-fold, respectively. In OFs, similar effects of CSE were seen on the expression of CYR61 (1.4-fold) and PTGS2 (3-fold). Simvastatin downregulated adipogenesis, PPAR-γ (2-fold) and SCD (27-fold) expression in OFs. CONCLUSION: CSE upregulated early adipogenic genes in both mouse 3T3-L1 preadipocytes and human OFs but did not by itself induce adipogenesis. Simvastatin inhibited the expression of both early and late adipogenic genes and adipogenesis in preadipocytes and human OFs. The effect of simvastatin should be investigated in a clinical trial of patients with GO.
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CONTEXT: A potentially altered protein expression profile in orbital tissue from patients with thyroid-associated orbitopathy (TAO) is suspected. OBJECTIVE: To detect for the first time changes in proteomic patterns of orbital connective tissue in TAO and compare these with control tissue using mass spectrometry. DESIGN: Proteomics cross-sectional, comparative study. SETTING: Two academic endocrine institutions. SAMPLES: A total of 64 orbital and peripheral adipose tissue samples were collected from 39 patients with TAO and 25 control subjects. METHODS: Samples were analyzed and identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry technology. MAIN OUTCOME MEASURES: Mean intensity values of all identified peptides per protein. RESULTS: Thirty-one proteins were identified, of which 16 differentiated between controls and patients with TAO. Different protein patterns between orbital and peripheral adipose tissue were observed. Compared to controls, 10 proteins were markedly up-regulated (≥ 2-fold) in the orbital tissue of untreated patients: beta IV spectrin (6.2-fold), GTP binding G protein 2 (5.6-fold), POTE ankyrin domain family member F (5.4-fold), xylulokinase (4.1-fold), kinesin family member 1A and lipocalin 1 (both 3.6-fold), semicarbazide-sensitive metalloproteinase amine oxidase 3 and polymerase I transcript release factor (both 3.4-fold), cell-cycle protein elongin A binding protein 1 (3.3-fold), annexin A2 and cavin (both 3-fold), protein pointing to cell proliferation histone H4 (2.8-fold), and ADAM metallopeptidase with thrombospondin type 1 motif 14 (2.7-fold). The highest protein up-regulations were noted in the orbital tissue of medically untreated patients. Steroid therapy markedly reduced up-regulation of these proteins, foremost in nonsmokers. CONCLUSIONS: Proteins involved in tissue inflammation, adipose tissue differentiation, lipid metabolism, and tissue remodeling were up-regulated in orbital tissue of untreated patients with TAO. Steroids decreased the expression of these proteins, whereas smoking attenuated such effect.
Asunto(s)
Oftalmopatía de Graves/genética , Oftalmopatía de Graves/metabolismo , Órbita/metabolismo , Proteómica , Enfermedades de la Tiroides/complicaciones , Tejido Adiposo/química , Tejido Adiposo/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Tejido Conectivo/metabolismo , Estudios Transversales , Femenino , Oftalmopatía de Graves/tratamiento farmacológico , Humanos , Metabolismo de los Lípidos/genética , Masculino , Persona de Mediana Edad , Órbita/química , Órbita/cirugía , Fumar/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Esteroides/uso terapéutico , Regulación hacia Arriba/efectos de los fármacos , Adulto JovenRESUMEN
Patients with low thyroid peroxidase antibodies (anti-TPO) and increased TSH-receptor antibodies (TRAb) at diagnosis of Graves' disease (GD) have been suggested to have an increased risk to develop Graves' ophthalmopathy (GO). The aim was to evaluate if GO development can be predicted.This is an observational study with registration of possible GD and GO risk factors.399 patients with GD were registered 2003-2008 in Malmö, Sweden and out of these 310 were retrospectively followed up to 6 years. The main outcome measures were anti-TPO titer, TRAb titer, smoking habits, radioiodine treatment and GO development.TRAb was assessed with a third generation assay at GD diagnosis in 231 patients. The proportion of patients with GO increased above the median 6.3 IU/L both at diagnosis of GD (p=0.001) and at follow-up (p=0.0001).The distribution of GO patients anti-TPO above or below 20 kIU/L at diagnosis of GD was similar between groups (p=0.239). However at follow-up anti-TPO<20 kIU/L was associated with an increased proportion of newly developed GO as compared to the cohort with anti-TPO>20 kIU/L (p=0.018).87% of patients who developed GO after GD diagnosis had TRAb above 6.3 IU/L and/or anti-TPO below 20 kIU/L. The proportion of GO was doubled in GD patients treated with radioiodine but could not explain the described findingsAnti-TPO<20 kIU/L and/or TRAb>6.3 IE/L at the time of GD diagnosis were associated with an increased risk to develop GO after diagnosis of GD.