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Background: Graves' orbitopathy (GO) is an autoimmune-driven manifestation of Graves' disease (GD) where pathogenic autoantibodies to the thyrotropin receptor (TSHR) activate orbital fibroblasts/preadipocytes in the orbital tissue to induce inflammation and extracellular matrix deposition. Since there are significant limitations to study immunological and proinflammatory mediator expression in early and during disease progression in GO patients, we used our experimental mouse model to elucidate early pathogenic processes. Methods: We have developed a robust mouse model of GD/GO induced by electroporation immunization of plasmid encoding human TSHR A-subunit, comprising multiple injections over a course of 15 weeks to fully recapitulate the orbital pathology. In this study, we investigated kinetics of GO development in the model by serial analyses of immunological and cellular parameters during course of orbital inflammation. Results: Pathogenic anti-TSHR antibodies with thyroid-stimulating properties developed early after the second immunization step with concomitant induction of hyperthyroidism. Examination of orbital tissue showed an early wave of macrophage infiltration followed subsequently by CD3 + T cells into the orbital tissue. Examination of antigen-specific T cell activity using recombinant human A-subunit protein showed high CD8 + T cell proliferation during this early phase of disease onset, whereas effector CD4 + T cells and CD25 + FOXP3 + regulatory T cells (Tregs) were downregulated. The early phase of disease was also characterized by abundant presence of proinflammatory cytokines interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α). Moreover, as the disease progressed, there was significant increase in browning of orbital fat tissue, which may be dependent on the proinflammatory milieu and/or the increased thyroid hormone levels during the established hyperthyroid status. Conclusions: This work revealed early infiltration of macrophages in the orbital region and induction of pathogenic anti-TSHR antibodies during disease onset in the model. This was followed subsequently by influx of CD8 + T cells specific for TSHR coupled with reduction in Tregs and substantial increase in brown adipose tissue. These new insights into the development of orbital inflammation in the model have implications for testing new therapeutic regimens by targeting macrophage function during early phases of orbital inflammation in the model.

Background: Adipogenesis, glycosaminoglycan hyaluronan (HA) production, inflammation, and fibrosis are the main pathogenic mechanisms responsible for Graves' orbitopathy (GO). We hypothesized that disulfiram (DSF), an aldehyde dehydrogenase (ALDH) inhibitor used to treat alcoholism, would have therapeutic effects on orbital fibroblasts (OFs) in GO. This study aimed at determining the therapeutic effects and underlying mechanisms of DSF on these parameters. Methods: Primary cultures of OFs from six GO patients and six control subjects were established. The OFs were allowed to differentiate into adipocytes and treated with various concentrations of DSF. Lipid accumulation within the cells was evaluated by Oil Red O staining. Real-time polymerase chain reaction (RT-PCR) and Western blotting were used to measure the expression of key adipogenic transcription factors, ALDH1A1, ALDH2, and mitogen-activated protein kinase (MAPK) signaling proteins. Apoptosis assays and reactive oxygen species levels were evaluated by flow cytometry. HA production was measured by using an enzyme-linked immunosorbent assay (ELISA) kit. The mRNA levels of proinflammatory molecules were measured by using RT-PCR after interleukin (IL)-1β stimulation with or without DSF. The mRNA expression of markers associated with fibrosis was examined by using RT-PCR after transforming growth factor (TGF)-β1 stimulation with or without DSF. The wound-healing assay was assessed by phase-contrast microscopy. Results: Under identical adipogenesis conditions, GO OFs effectively differentiated, while normal control (NC) OFs did not. DSF dose dependently suppressed lipid accumulation during adipogenesis in GO OFs. The expression of key adipogenic transcription factors, such as perilipin-1 (PLIN1), PPARγ (PPARG), FABP4, and c/EBPα (CEBPA), was downregulated. Further, DSF inhibited the phosphorylation of ERK by inhibiting ALDH1A1. In addition, DSF attenuated HA production and suppressed inflammatory molecule expression induced by IL-1β in GO OFs and NC OFs. The antifibrotic effects of DSF on TGF-β1 were also observed in GO OFs. Conclusions: In the current study, we provide evidence of the inhibitory effect of DSF on GO OFs adipogenesis, HA production, inflammation, and fibrosis in vitro . The results of this study are noteworthy and indicate the potential use of DSF as a therapeutic agent for the treatment of GO.

Background: Graves' disease accounts for ∼80% of all cases of hyperthyroidism and is associated with significant morbidity and decreased quality of life. Understanding the association of total thyroidectomy with patient-reported quality-of-life and thyroid-specific symptoms is critical to shared decision-making and high-quality care. We estimate the change in patient-reported outcomes (PROs) before and after surgery for patients with Graves' disease to inform the expectations of patients and their physicians. Methods: PROs using the MD Anderson Symptom Inventory (MDASI) validated questionnaire were collected prospectively from adult patients with Graves' disease from January 1, 2015, to November 20, 2020, on a longitudinal basis. Survey responses were categorized as before surgery (≤120 days), short term after surgery (<30 days; ST), and long term after surgery (≥30 days; LT). Negative binomial regression was used to estimate the association of select covariates with PROs. Results: Eighty-five patients with Graves' disease were included. The majority were female (83.5%); 47.1% were non-Hispanic white and 35.3% were non-Hispanic black. The median thyrotropin (TSH) value before surgery was 0.05, which increased to 0.82 in ST and 1.57 in LT. In bivariate analysis, the Total Symptom Burden Score, a composite of all patient-reported burden, significantly reduced shortly after surgery (before surgery mean of 56.88 vs. ST 39.60, p  < 0.001), demonstrating improvement in PROs. Furthermore, both the Thyroid Symptoms Score, including patient-reported thermoregulation, palpitations, and dysphagia, and the Quality-of-Life Symptom Score improved in ST and LT (thyroid symptoms, before surgery 13.88 vs. ST 8.62 and LT 7.29; quality of life, before surgery 16.16 vs. ST 9.14 and LT 10.04, all p  < 0.05). After multivariate adjustment, the patient-reported burden in the Thyroid Symptom Score and the Quality-of-Life Symptom Score exhibited reduction in ST (thyroid symptoms, rate ratio [RR] 0.55, confidence interval [CI]: 0.42-0.72; quality of life, RR 0.57, CI: 0.40-0.81) and LT (thyroid symptoms, RR 0.59, CI: 0.44-0.79; quality of Life, RR 0.43, CI: 0.28-0.65). Conclusions: Quality of life and thyroid-specific symptoms of Graves' patients improved significantly from their baseline before surgery to both shortly after and longer after surgery. This work can be used to guide clinicians and patients with Graves' disease on the expected outcomes following total thyroidectomy.

Background: Patients with Graves' disease are commonly treated with radioiodine. There remains controversy over whether the aim of treatment should be to achieve euthyroidism or hypothyroidism, and whether treatments should be administered with standard levels of radioactivity or personalized according to the radiation absorbed doses delivered to the thyroid. The aim of this review was to investigate whether a relationship exists between radiation absorbed dose and treatment outcome. Methods: A systematic review and meta-analysis of all reports published before February 13, 2020, were performed using PubMed, Web of Science, OVID MEDLINE, and Embase. Proportion of patients achieving nonhyperthyroid status was the primary outcome. Secondary outcomes were proportion of patients who were specifically euthyroid or hypothyroid. A random-effects meta-analysis of proportions was performed for primary and secondary outcomes, and the impact of the radiation absorbed dose on treatment outcome was assessed through meta-regression. The study is registered with PROSPERO (CRD42020175010). Results: A total of 1122 studies were identified of which 15, comprising 2303 Graves' disease patients, were eligible for the meta-analysis. A strong association was found between radiation absorbed dose and nonhyperthyroid and hypothyroid outcomes (odds ratio [OR] = 1.11 [95% confidence interval {CI} 1.08-1.14] and OR = 1.09 [CI 1.06-1.12] per 10 Gy increase). Higher rates of euthyroid outcome were found for radiation absorbed doses within the range 120-180 Gy when compared with outside this range ( n  = 1172, OR = 2.50 [CI 1.17-5.35], p  = 0.018). A maximum euthyroid response of 38% was identified at a radiation absorbed dose of 128 Gy. Conclusions: The presented radiation absorbed dose-response relationships can facilitate personalized treatment planning for radioiodine treatment of patients with Graves' disease. Further studies are required to determine how patient-specific covariates can inform personalized treatments.

Background: The autoimmune/inflammatory syndrome induced by adjuvants (ASIA) comprises four entities, including the postvaccination phenomenon, which appears after being exposed to adjuvants in vaccines that increase the immune response. There is limited information about autoimmune endocrine diseases and ASIA after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. Patient's Findings: Two female health care workers received a SARS-CoV-2 vaccine, and three days later developed clinical manifestations of thyroid hyperactivity, with increased thyroid hormone levels on thyroid function tests, suppressed thyroid-stimulating hormone, and elevated antithyroid antibodies. Summary: Vaccines have been shown to trigger an immune response that leads to a broad spectrum of autoimmune diseases, including autoimmune thyroid disease. Our patients met the diagnostic criteria for ASIA; they were exposed to an adjuvant (vaccine), and they developed clinical manifestations of thyroid hyperfunction within a few days, with the appearance of antithyroid antibodies, despite being healthy before vaccination. Conclusion: Graves' disease can occur after SARS-CoV-2 vaccination.

Background: The prognosis of Graves' disease (GD) is reportedly related to sex, age, and genetic factors, although there is no consensus. The objective of this study was to investigate the relationship between severity and prognosis of GD and sex or age. Methods: Subjects were patients newly diagnosed with GD between January 2005 and June 2019, and medical records were retrospectively reviewed. Patients diagnosed between January 2009 and December 2010 and followed up for at least 12 months were enrolled. Patients were divided into nine age-stratified groups. Remission was defined as maintenance of a euthyroid state for more than one year after withdrawal of antithyroid drugs (ATDs). Results: Participants comprised 21,633 patients (3954 males, 17,679 females). Initial free triiodothyronine (fT3) and free thyroxine (fT4) levels significantly decreased with increasing age, including after sex stratification. fT4 was significantly higher in males than females aged 20-39 years. In 2191 patients treated with ATDs alone, median durations until remission were 37.7 and 30.6 months in males and females, respectively. Remission and recurrence were observed in 1391 patients (204 males, 1187 females) and 262 patients (37 males, 225 females), respectively. By Kaplan-Meier analyses, males required a significantly longer time to achieve remission than females ( p  < 0.0001), although there were no significant age-related differences ( p  = 0.08). Cox proportional hazard modeling showed a 41% higher hazard ratio (HR) for remission in females than males (adjusted HRs [aHR] confidence interval [CI] = 1.41 [1.21-1.64]), and each additional 10 years of age had a 14% lower rate of recurrence (age [per 10-year increase], aHR [CI] = 0.86 [0.78-0.94]); no significant relationship between recurrence rate and sex was identified. Conclusions: Severity of hyperthyroidism in GD was significantly higher in males in their 20s and 30s, declining with advancing age in both sexes. Females were more likely to achieve remission than males, and younger patients had a higher risk of recurrence, although recurrence was unrelated to sex.

Background: Several studies have investigated the factors affecting the effects of radioactive iodine ( 131 I) treatment (RAIT) in patients with Graves' disease. However, the influence of dietary or therapeutic iodine on the effect of RAIT has not been fully elucidated yet. The aim of this study was to investigate whether dietary or therapeutic iodine before RAIT influences the therapeutic effects of RAIT with a fixed-dose regimen and a short-term restriction of iodine intake in an iodine-sufficient area. Materials and Methods: We retrospectively analyzed 81 Japanese patients with Graves' disease treated with the following RAIT regimen: dietary iodine restriction for 7 days as well as discontinuation of antithyroid drugs (ATDs), potassium iodine (KI), or both for 5 days before RAIT. On the day of RAIT, we measured urinary iodine content to estimate daily iodine intake. After RAIT, we adjusted the dose of ATDs, KI, or both according to serum thyroid hormone levels every 1-2 months. Using the data from these patients, we investigated the effect of dietary and therapeutic iodine on the therapeutic effects of RAIT. The therapeutic effects at 1 year after RAIT were evaluated based on the necessity of ATDs, KI, or both. Results: Dietary iodine intake was weakly correlated with 131 I uptake (RAIU), but the dose of therapeutic iodine was not correlated with RAIU. The therapeutic effects of RAIT were strongly negatively associated with estimated thyroid volume before RAIT. Neither dietary iodine intake nor therapeutic iodine before RAIT affected this association. Conclusion: This study did not find an association between short-term dietary or therapeutic iodine restriction before RAIT and the therapeutic effects of RAIT in an iodine-sufficient area.

Background: The overall changes of ocular motility in Graves' orbitopathy (GO) are not easily quantifiable with the methods currently available, especially in clinical studies. The aim of the present study was to calculate parameters that quantify the changes of ocular motility in GO in relation to the Gorman score for diplopia. Methods: We studied 100 GO patients (Group 1) and 100 controls (Group 2). We also included 30 patients treated with intravenous methylprednisolone (iv-MP), assessed at baseline and after 12 and 24 weeks (Group 3), and 66 patients submitted to squint surgery, assessed at baseline and after 12 weeks (Group 4). Ocular ductions were measured in four gaze directions by a perimeter arc and were used to calculate a total motility score (TMS) as the sum of ductions in each direction; a biocular TMS (b-TMS) as the sum of the TMS of two eyes; and an asymmetry ratio (AR) as the sum of the differences of the corresponding ductions between the two fellow eyes divided by the mean difference found in controls. Quality of life was accessed by a specific questionnaire (Graves' orbitopathy quality of life [GO-QoL] questionnaire). Results: TMS and b-TMS were lower, while AR was higher, in Group 1 compared with controls ( p  < 0.001). In Group 1, TMS and b-TMS were inversely correlated with the Gorman score ( p  < 0.001) and AR was higher in patients with constant diplopia compared with the others ( p  < 0.001). In Group 3, TMS and b-TMS increased after treatment in responders to iv-MP ( p  < 0.001). In Group 4, TMS and b-TMS improved in all patients after surgery ( p  < 0.01), while AR and GO-QoL score improved only in those without residual constant diplopia ( p  < 0.001). Conclusion: We describe a quantitative method to assess eye motility dysfunction in any stage of GO to be used as an outcome measure in clinical studies.

Background: Radioiodine (RAI) is a known risk factor for activation or de novo occurrence of Graves' orbitopathy (GO). Several studies demonstrated that GO can be prevented by glucocorticoids (GCs) in patients with pre-existing GO. We have previously shown that Graves' disease duration (GDd) <5 years is a risk factor for RAI-induced GO. We studied the effect of prophylaxis with either oral GCs (OGCs) or intravenous GCs (IVGCs) on GO activation in patients with GDd. Methods: In total, 99 hyperthyroid patients without GO or with pre-existing inactive GO with GDd <5 years were randomized to receive IVGCs ( N  = 49) or OGCs ( N  = 50) before RAI; 22 patients with GDd >5 did not receive steroids and were studied as controls. All patients underwent ophthalmological assessment before and 45, 90, 180 days and for a 5-year follow-up after RAI. Serum thyrotropin (TSH) receptor antibodies (TRAbs), thyroid hormones, and thyroid volume (TV) were also measured in response to RAI therapy and steroid prophylaxis. Results: No patient on prophylaxis developed GO after RAI. One woman of the control group, without steroid prophylaxis, and who had a marked elevation of her TSH, showed transient reactivation of GO, which spontaneously improved after restoring euthyroidism. On follow-up at 12 and 20 months after RAI, two patients developed overt optic neuropathy. A smaller TV was associated with a higher prevalence of RAI-induced hypothyroidism. Serum TRAbs increased significantly after RAI ( p  < 0.0001) but less in patients receiving steroids than in those without prophylaxis at 45 days ( p  < 0.01). Conclusions: The risk of RAI-induced GO can be prevented in all patients with GDd <5 years by steroids. Such treatment may not be necessary in patients with GDd >5 years. The blunting of TRAb elevation after RAI may be related to the prophylactic effect of steroids.

Background: Previous in vitro experiments have demonstrated that prostaglandin F2-alpha (PF 2α ) reduced proliferation and adipogenesis in a murine cell line and human orbital fibroblasts derived from subjects with inactive Graves' orbitopathy (GO). The objective of this study was to determine if the PGF 2α analogue bimatoprost is effective at reducing proptosis in this population., Methods: A randomized controlled double-masked crossover trial was conducted in a single tertiary care academic medical center. Patients with long-standing, inactive GO but persistent proptosis (>20 mm in at least one eye) were recruited. Allowing for a 15% dropout rate, 31 patients (26 females) were randomized in order to identify a treatment effect of 2.0 mm (p = 0.05; power 0.88). Following informed consent, participants were randomized to receive bimatoprost or placebo for three months, after which they underwent a two-month washout before switching to the opposite treatment. The primary outcome was the change in exophthalmometry readings over the two three-month treatment periods., Results: The mean exophthalmometer at baseline was 23.6 mm (range 20.0-30.5 mm), and the mean age of the patients was 55 years (range 28-74 years). The median duration of GO was 7.6 years (interquartile range 3.6-12.3 years). The majority were still suffering from diplopia (61.3%) with bilateral involvement (61.3%). Using multi-level modeling adjusted for baseline, period, and carry-over, bimatoprost resulted in a -0.17 mm (reduction) exophthalmometry change ([confidence interval -0.67 to +0.32]; p = 0.490). There was a mean change in intraocular pressure of -2.7 mmHg ([confidence interval -4.0 to -1.4]; p = 0.0070). One patient showed periorbital fat atrophy on treatment, which resolved on stopping treatment. Independent analysis of proptosis by photographic images (all subjects) and subgroup analysis on monocular disease (n = 12) did not show any apparent benefit., Conclusions: In inactive GO, bimatoprost treatment over a three-month period does not result in an improvement in proptosis.

Background: The thyrotropin receptor (TSHR) is the target for autoimmune thyroid stimulating antibodies (TSAb) triggering hyperthyroidism. Whereas elevated thyroid hormone synthesis by the thyroid in Graves' disease can be treated by antithyroid agents, for the pathogenic activation of TSHR in retro-orbital fibroblasts of the eye, leading to Graves' orbitopathy (GO), no causal TSHR directed therapy is available., Methods: Due to the therapeutic gap for severe GO, TSHR inhibitors were identified by high-throughput screening in Chinese hamster ovary cells expressing the TSHR. Stereo-selective synthesis of the screening hits led to the molecule S37, which contains seven chiral centers. Enantiomeric separation of the molecule S37 resulted in the enantiopure molecule S37a-a micro-molar antagonist of thyrotropin-induced cyclic adenosine monophosphate accumulation in HEK 293 cells expressing the TSHR., Results: The unique rigid bent shape of molecule S37a may mediate the observed high TSHR selectivity. Most importantly, the closely related follitropin and lutropin receptors were not affected by this compound. S37a not only inhibits the TSHR activation by thyrotropin itself but also activation by monoclonal TSAb M22 (human), KSAb1 (murine), and the allosteric small-molecule agonist C2. Disease-related ex vivo studies in HEK 293 cells expressing the TSHR showed that S37a also inhibits cyclic adenosine monophosphate formation by oligoclonal TSAb, which are highly enriched in GO patients' sera. Initial in vivo pharmacokinetic studies revealed no toxicity of S37a and a remarkable 53% oral bioavailability in mice., Conclusion: In summary, a novel highly selective inhibitor for the TSHR is presented, which has promising potential for further development for the treatment of GO.

Background: It was hypothesized that the biguanides metformin and phenformin, which are anti-hyperglycemic drugs used for diabetes mellitus, would have therapeutic effects in an in vitro model of Graves' orbitopathy (GO). Because adipogenesis, hyaluronan production, and inflammation are considered important in the pathogenesis of GO, this study aimed to determine the therapeutic effects and underlying mechanisms of biguanides on these parameters., Methods: In vitro experiments were performed using primary cultured orbital fibroblasts from patients with GO. Orbital preadipocyte fibroblasts were allowed to differentiate into adipocytes and were treated with various concentrations of metformin or phenformin. Oil Red O staining was performed to evaluate lipid accumulation within the cells. Western blot analysis was used to measure the expression of adipogenic transcription factors and the phosphorylation of AMP-activated protein kinase and mitogen-activated protein kinase signaling proteins. Hyaluronan production was measured using enzyme-linked immunosorbent assay, and mRNA levels of proinflammatory molecules were determined using real-time polymerase chain reaction after interleukin (IL)-1β stimulation with or without biguanide treatment., Results: Lipid accumulation during adipogenesis in GO orbital fibroblasts was dose-dependently suppressed by both metformin and phenformin. Adipocyte differentiation was attenuated, and the adipogenic transcription factors peroxisome proliferator-activated receptor γ and CCAAT-enhancer-binding proteins-α/β were downregulated. Furthermore, metformin and phenformin increased the phosphorylation of AMP-activated protein kinase and suppressed extracellular-regulated kinase activation. The IL-1β-induced hyaluronan production and mRNA expression of IL-6, cyclooxygenase-2, and intercellular adhesion molecule-1 were also significantly suppressed after metformin or phenformin co-treatment., Conclusions: The present study indicates that the biguanides metformin and phenformin exert an anti-adipogenic and inhibitory effect on hyaluronan production and expression of pro-inflammatory molecules in GO orbital fibroblasts, suggesting that they could potentially be used for the treatment of GO.

Background: Limited data suggest that treatment with statins is associated with a reduced risk of Graves' orbitopathy (GO) in patients with Graves' disease (GD), attributed to the anti-inflammatory rather than to the hypolipemic effects of these medications. The aim of the present study was to investigate whether there is an association between high cholesterol and GO. The primary outcome was the relation between GO and low-density lipoprotein (LDL)-cholesterol. The secondary outcomes were the relation between severity or activity (the clinical activity score [CAS]) of GO and LDL-cholesterol., Methods: A cross-sectional investigation was conducted in consecutive patients with GD who came under the authors' observation to undergo radioiodine treatment, a stratification aimed at forming two distinct groups of patients under the same conditions. A total of 250 patients were enrolled, 133 with and 117 without GO. Ophthalmological assessments and serum lipids measurements were performed., Results: In multivariate analyses with correction for the duration of hyperthyroidism, a variable that differed between patients with respect to the presence or absence of GO, a correlation between the presence of GO and both total (p = 0.01) and LDL-cholesterol (p = 0.02) was observed. In patients with hyperthyroidism lasting <44 months, total and LDL-cholesterol were higher (p = 0.01 and p = 0.008, respectively) among GO patients. In this subgroup, based on the presence/absence of GO, cutoff values were established for total (191 mg/dL) and LDL-cholesterol (118.4 mg/dL), above which an increased risk of GO was observed (total cholesterol relative risk: 1.47; p = 0.03; LDL-cholesterol relative risk: 1.28; p = 0.03). GO severity and CAS did not correlate with serum lipids. However, CAS was found to be higher (p = 0.02) in patients with high total cholesterol. When the analysis was restricted to untreated GO patients, a correlation was found between CAS and both total (p = 0.04) and LDL-cholesterol (p = 0.03), after adjustment for GO duration., Conclusions: In patients with a short duration of hyperthyroidism, total and LDL-cholesterol correlate with the presence of GO, suggesting a role of cholesterol in the development of GO. Depending on GO duration, total and LDL-cholesterol correlate with GO activity, suggesting a role of cholesterol in the clinical expression of GO.

Background: There are currently no reliable biomarkers to predict relapse in Graves' disease (GD). In the present study, we investigated novel diagnostic biomarkers to predict the long-term remission of or relapse in GD., Methods: A DNA microarray analysis was performed to examine gene expression in the peripheral leukocytes of a frequently relapsing patient with GD and a patient in long-term remission after the discontinuation of antithyroid drugs (ATDs). Based on the DNA microarray analysis, we focused on Sialic acid-binding immunoglobulin-like lectin1 (SIGLEC1) as a candidate novel biomarker to predict GD relapse. Three hundred and fifty-eight patients with GD in the thyroid clinics of four different hospitals in Japan were included in a cross-sectional study to establish whether SIGLEC1 mRNA levels distinguish GD relapse experience from long-term remission. An additional 55 patients with GD were enrolled in a prospective study to clarify whether SIGLEC1 mRNA levels at ATD discontinuation predict GD relapse., Results: SIGLEC1 mRNA levels were significantly higher in patients with GD relapse experience than in those in long-term remission. Based on the receiver operating characteristic analysis, we found that high SIGLEC1 mRNA levels (≥258.9 copies) significantly distinguished GD relapse experience from long-term remission (p < 0.0001; sensitivity 66.7%, specificity 70.1%). In the prospective study, when the optimal cutoff value from the receiver operating characteristic curve analysis was applied to SIGLEC1 mRNA positivity at ATD discontinuation, SIGLEC1-positive patients (≥258.9 copies) showed a significantly higher cumulative risk of relapse than SIGLEC1-negative patients (<258.9 copies) (p = 0.022, the log-rank test)., Conclusions: SIGLEC1 mRNA levels have potential as a novel predictive biomarker for GD relapse.

Background: A recent clinical trial has shown a beneficial effect of the antioxidant agent selenium in Graves' orbitopathy (GO). In order to shed light on the cellular mechanisms on which selenium may act, this study investigated its effects in cultured orbital fibroblasts., Methods: Primary cultures of orbital fibroblasts from six GO patients and six control subjects were established. Cells were treated with H 2 O 2 to induce oxidative stress, after pre-incubation with selenium-(methyl)selenocysteine (SeMCys). The following assays were performed: glutathione disulfide (GSSG), as a measure of oxidative stress, glutathione peroxidase (GPX) activity, cell proliferation, hyaluronic acid (HA), and pro-inflammatory cytokines., Results: H 2 O 2 induced an increase in cell GSSG and fibroblast proliferation, which were reduced by SeMCys. Incubation of H 2 O 2 -treated cells with SeMCys was followed by an increase in glutathione peroxidase activity, one of the antioxidant enzymes into which selenium is incorporated. At the concentrations used (5 μM), H 2 O 2 did not significantly affect HA release, but it was reduced by SeMCys. H 2 O 2 determined an increase in endogenous cytokines involved in the response to oxidative stress and GO pathogenesis, namely tumor necrosis factor alpha, interleukin 1 beta, and interferon gamma. The increases in tumor necrosis factor alpha and interferon gamma were blocked by SeMCys. While the effects of SeMCys on oxidative stress and cytokines were similar in GO and control fibroblasts, they were exclusive to GO fibroblasts in terms of inhibiting proliferation and HA secretion., Conclusions: Selenium, in the form of SeMCys, abolishes some of the effects of oxidative stress in orbital fibroblasts, namely increased proliferation and secretion of pro-inflammatory cytokines. SeMCys reduces HA release in GO fibroblasts in a manner that seems at least in part independent from H 2 O 2 -induced oxidative stress. Some effects of SeMCys are specific for GO fibroblasts. These findings reveal some cellular mechanisms by which selenium may act in patients with GO.