Current Insights into the Pathogenesis of Graves' Ophthalmopathy

Impact of ibrutinib on inflammation in a mouse model of Graves' orbitopathy

Introduction

Bruton's tyrosine kinase (BTK) and interleukin (IL)-2 Inducible T-cell Kinase (ITK) inhibitors have anti-inflammatory properties. We investigated the therapeutic effect of ibrutinib, an orally bioavailable BTK/ITK inhibitor, in a mouse model of Graves' orbitopathy (GO).

Methods

Genetic immunization was performed through intramuscular administration of the recombinant plasmid, pCMV6-hTSHR cDNA, to 8-week-old female BALB/c mice. Serum levels of T3, T4, and thyroid-stimulating hormone receptor (TSHR) antibodies (TRAbs) were quantified using enzyme-linked immunosorbent assay. Histopathological changes in orbital tissues were examined using immunohistochemistry (IHC) staining for TSHR and various inflammatory markers. Following successful genetic immunization, ibrutinib was orally administered daily for 2 weeks in the GO model mice. After treatment, the mRNA and protein expression levels of BTK, ITK, IL-1β, and IL-6 in orbital tissues were evaluated using real-time PCR and Western blotting.

Results

In total, 20 mice were sacrificed to confirm successful genetic immunization. The GO mouse group exhibited significantly increased serum T3, T4, and TRAb levels. IHC revealed increased expression of TSHR, IL-1β, IL-6, transforming growth factor-β1, interferon-γ, CD40, CD4, BTK, and ITK in the GO mouse model. The orbital inflammation was significantly attenuated in ibrutinib-treated mice. The mRNA and protein expression levels of BTK, ITK, IL-1β, and IL-6 in orbital tissue were lower in ibrutinib-treated GO mouse group compared to the phosphate-buffered saline-treated GO mouse group.

Conclusion

The GO mouse model demonstrated enhanced BTK and ITK expression. Ibrutinib, a BTK/ITK inhibitor, suppressed the inflammatory cytokine production. These findings highlight the potential involvement of BTK/ITK in the inflammatory pathogenesis of GO, suggesting its role as a novel therapeutic target.

Effect of traditional Chinese medicine on Graves' disease: a network meta-analysis

Introduction: Graves' disease (GD) is the most common cause of hyperthyroidism and can affect multiple systems of the body. Currently, commonly-used treatment methods for GD have a series of shortcomings. In contrast, traditional Chinese medicine has been proven to be effective in inhibiting the progression of GD and is expected to become a key direction for the development of new drugs in the future. Therefore, a network meta-analysis was performed to compare the impacts of different traditional Chinese medicines on the curative effect, thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), thyroglobulin antibody (TGAb), thyroid peroxidase antibody (TPOAb) and thyrotropin receptor antibody (TRAb) in patients with GD. Methods: PubMed, Embase, Cochrane Library, Web of Science, WanFang, Weipu, and CNKI were searched for the randomized controlled trials of traditional Chinese medicine on GD patients up to 19 December 2023. The quality of the included studies was evaluated regarding the risk of bias, and the data were analyzed by R software. Results: Thirty-five articles were included in the analysis, involving 2828 GD patients and traditional Chinese medicines including Bailing Capsule, Jinshuibao Capsule, Astragalus injection, Jiakangling Tablet, Jiakangling Capsule, Tripterygium Wilfordii, Sanjie Xiaoying Decoction, Prunella vulgaris (L.) Oral Liquid, P. vulgaris (L.) Granules, Xiehuo Xiaoying Recipe, Xiehuo Yangyin Powder, Yikang Pill and Yinjia Pellet. The results of network meta-analysis suggested that for GD patients, Bailing Capsule, Jiakangling Capsule, Tripterygium wilfordii, P. vulgaris (L.) Oral Liquid and Yinjia Pellet had better curative effect compared with Western medicine. Prunella vulgaris (L.) Granules and Yikang Pill could improve the TSH level. Prunella vulgaris (L.) Granules, P. vulgaris (L.) Oral Liquid and Yikang Pill could reduce FT3 level. Jiakangling Capsule, P. vulgaris (L.) Granules, P. vulgaris (L.) Oral Liquid and Yikang Pill could reduce the FT4 level. Prunella vulgaris (L.) Oral Liquid can reduce the level of TPOAb and TRAb. Besides, Yinjia Pellet was the most helpful in improving the curative effect. Yikang Pill could best improve TSH. Prunella vulgaris (L.) Granules had the best effect on reducing FT3. Prunella vulgaris (L.) Granules performed best in reducing FT4. Prunella vulgaris (L.) Oral Liquid had the most favorable effect on reducing TPOAb and TRAb. Conclusion: Based on the current research, it is safe to conclude that Chinese medicine can improve the curative effect and TSH level of patients with GD, and reduce the levels of FT3, FT4, TPOAb and TRAb. Besides, Yinjia Pellet is the most helpful in improving the curative effect. Yikang Pill can best improve TSH. Prunella vulgaris (L.) Granules have the best effect on reducing FT3. Prunella vulgaris (L.) Granules perform best in reducing FT4. Prunella vulgaris (L.) Oral Liquid has the most favorable effect on reducing TPOAb and TRAb. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/#recordDetails, identifier CRD42024521912.

Optical coherence tomography angiography in thyroid associated ophthalmopathy: a systematic review

PURPOSE

To evaluate the evidence for alterations of blood flow, vascular and perfusion densities in the choroid, macula, peripapillary region, and the area surrounding the optic nerve head (ONH) in patients with thyroid-associated ophthalmopathy (TAO) based on changes of OCTA parameters.

METHODS

A systematic review of Pubmed, Google Scholar, Scopus, WOS, Cochrane, and Embase databases, including quality assessment of published studies, investigating the alterations of OCTA parameters in TAO patients was conducted. The outcomes of interest comprised changes of perfusion and vascular densities in radial peripapillary capillary (RPC), ONH, superficial and deep retinal layers (SRL and DRL), choriocapillaris (CC) flow, and the extent of the foveal avascular zone (FAZ).

RESULTS

From the total of 1253 articles obtained from the databases, the pool of papers was narrowed down to studies published until March 20th, 2024. Lastly, 42 studies were taken into consideration which contained the data regarding the alterations of OCTA parameters including choriocapillary vascular flow, vascular and perfusion densities of retinal microvasculature, SRL, and DRL, changes in macular all grid sessions, changes of foveal, perifoveal and parafoveal densities, macular whole image vessel density (m-wiVD) and FAZ, in addition to alterations of ONH and RPC whole image vessel densities (onh-wiVD and rpc-wiVD) among TAO patients. The correlation of these parameters with visual field-associated parameters, such as Best-corrected visual acuity (BCVA), Visual field mean defect (VF-MD), axial length (AL), P100 amplitude, and latency, was also evaluated among TAO patients.

CONCLUSION

The application of OCTA has proven helpful in distinguishing active and inactive TAO patients, as well as differentiation of patients with or without DON, indicating the potential promising role of some OCTA measures for early detection of TAO with high sensitivity and specificity in addition to preventing the irreversible outcomes of TAO. OCTA assessments have also been applied to evaluate the effectiveness of TAO treatment approaches, including systemic corticosteroid therapy and surgical decompression.

Graves disease: latest understanding of pathogenesis and treatment options

Graves disease is the most common cause of hyperthyroidism in iodine-sufficient areas. The main responsible mechanism is related to autoantibodies that bind and activate the thyrotropin receptor (TSHR). Although Graves hyperthyroidism is relatively common, no causal treatment options are available. Established treatment modalities are antithyroid drugs, which reduce thyroid hormone synthesis, radioactive iodine and surgery. However, emerging drugs that target the main autoantigen (monoclonal antibodies, small molecules, peptides) or block the immune pathway have been recently tested in clinical trials. Graves disease can involve the thyroid exclusively or it can be associated with extrathyroidal manifestations, among which Graves orbitopathy is the most common. The presence of Graves orbitopathy can change the management of the disease. An established treatment for moderate-to-severe Graves orbitopathy is intravenous glucocorticoids. However, recent advances in understanding the pathogenesis of Graves orbitopathy have allowed the development of new target-based therapies by blocking pro-inflammatory cytokine receptors, lymphocytic infiltration or the insulin-like growth factor 1 receptor (IGF1R), with several clinical trials providing promising results. This article reviews the new discoveries in the pathogenesis of Graves hyperthyroidism and Graves orbitopathy that offer several important tools in disease management.

[Graves' orbitopathy as the cause of diplopia in old age-Differences between young and old]

BACKGROUND

Endocrine orbitopathy (EO) is an autoimmune disease mostly associated with a disease of the thyroid gland, which leads to inflammation, adipogenesis and fibrosis. The severity of EO can vary greatly between individuals, which makes it difficult to exactly predict the natural course of the disease; however, this is important to be able to individually adapt the treatment. The aim of this study was to compare the clinical features, course, treatment and prognosis for patients with EO under 50 years old with older patients. The results of the study with a focus on motility are presented in this special issue.

PATIENTS AND METHODS

The hospital records of a randomly selected sample of 1000 patients from the EO databank in Essen (GODE), which includes 4260 patients, were analyzed. The patients were divided into two groups: group 1 ≤50 years and group 2 >50 years. Only patients with complete data sets were included in the statistical analyses.

RESULTS

Younger patients (n = 484) presented significantly more frequently with milder EO (53% vs. 33%, p < 0.0001), whereas older patients (n = 448) more frequently suffered from moderate or severe forms (44% vs. 64%, p < 0.0001). Older patients showed more severe strabismus, motility and clinical activity scores (5.9 vs. 2.3 prism diopters, PD/310° vs. 330°, both p < 0.0001, CAS 2.1 vs. 1.7, p = 0.001). Proptosis and the occurrence of optic nerve compression showed no significant differences between the groups (3% each). Multiple logistic regression showed that the necessity for a second eye muscle surgery was most strongly associated with a previous decompression (OR = 0.12, 95 % CI 0.1-0.2, p < 0.0001), followed by orbital irradiation and age.

CONCLUSION

In summary, younger patients with EO presented with milder clinical features, such as a lower rate of restrictive motility disorders and weaker expression of signs of inflammation. Therefore, older patients needed steroids, irradiation, eyelid and eye muscle surgery more frequently; however, the risk of dysthyroid optic neuropathy and the necessity of a second eye surgery were not or only slightly associated with age.

Statins and thyroid eye disease (TED): a systematic review

PURPOSE

Thyroid eye disease (TED) is the foremost extrathyroidal manifestation of Graves' disease (GD). Currently, available treatments do not entirely prevent the long-term consequences of TED and have distinct disadvantages. Therefore, this systematic review explored available evidence regarding the efficacy of statins in preventing and treating TED.

METHODS

Relevant studies investigating statin usage in patients with GD or TED were identified by searching Medline (Pubmed and Ovid), Scopus, Web of Science, ProQuest, and Cochrane Library databases (from the database inception to September 2023). The review was done according to the PRISMA statement. Web searching was done independently by two investigators. Two researchers independently extracted the data, and any disagreement was adjudicated by consensus. Based on the study design, the studies' quality appraisal was done using the Newcastle-Ottawa Scale (NOS) and Version 2 of the Cochrane risk-of-bias tool (RoB2).

RESULTS

The literature search identified 145 publications, of which four met the inclusion criteria (Three retrospective cohort studies and one randomized clinical trial) and were reviewed in full text. The two retrospective cohort studies demonstrated the beneficial effects of statins on TED in newly diagnosed GD Stein et al. showed that statins, regardless of the type, prevent or delay TED (HR: 0.74 (0.65-0.84)), especially in men or treatment duration of more than one year. Nilsson et al. fascinatingly revealed that at least 60 days of statin usage in the preceding year could decrease the risk of TED development by around 40%. One RCT showed a higher treatment response for active moderate-to-severe TED in patients with hypercholesterolemia who took atorvastatin 20 mg in addition to ivGC for 24 weeks without any increase in serious side effects. The retrospective study revealed that the need for reconstructive surgery was reduced in patients with severe TED who received statin therapy.

CONCLUSION

Statin therapy could be a potential adjunctive modality for preventing and treating TED.

TRIAL REGISTRATION

PROSPERO registration number: CRD42022315522.

Graves' orbitopathy development in thyroid cancer patients: a 16-year nationwide cohort study in South Korea

BACKGROUND/OBJECTIVES

We aimed to investigate the prevalence, risk factors, and prognosis of Graves' orbitopathy (GO) in patients with thyroid cancer without a history of hyperthyroidism.

SUBJECTS/METHODS

This retrospective cohort study analysed a sample from the Korean National Health Insurance Service database, which included 1,137,861 subjects from 2002 through 2019. Patients diagnosed with thyroid cancer, without a history of hyperthyroidism, were identified according to the Korean Standard Classification of Disease codes. The study compared the type of surgery, dose of radioactive iodine (RAI), and daily average thyroid hormone dose between patients who developed GO after being diagnosed with thyroid cancer and those who did not develop GO. We analysed the course of GO and the type of treatment.

RESULTS

A total of 8499 cancer patients without a history of hyperthyroidism were identified, among whom 7836 underwent thyroidectomy. Of those who underwent thyroidectomy, 12 developed GO postoperatively. Among the 663 patients who did not undergo thyroidectomy, none developed GO. The prevalence of GO among thyroid cancer patients was 0.14%. The GO group received a significantly higher total RAI dose than the non-GO group (p = 0.036). There were no significant differences in sex, age, type of surgery, rate of RAI treatment, or average thyroid hormone dose between the two groups. One of the 12 patients who developed GO required intravenous steroids.

CONCLUSIONS

Although GO rarely develops in thyroid cancer patients without coexisting hyperthyroidism, the total RAI dose may increase its risk. Further research would help clarify GO's association with thyroid cancer.

Cyclosporin A inhibits PDGF-BB induced hyaluronan synthesis in orbital fibroblasts

Orbital connective tissue changes are contributors to the pathogenesis in thyroid eye disease (TED). Activated fibroblasts respond to immune stimuli with proliferation and increased hyaluronan (HA) production. Cyclosporin A (CsA) was reported to be beneficial in the treatment of TED. PDGF isoforms are increased in orbital tissue of TED patients and enhance HA production. We aimed to study the effect of CsA on HA production and hyaluronan synthase (HAS1, 2 and 3) and hyaluronidase (HYAL1 and 2) mRNA expressions in orbital fibroblasts (OFs). Measurements were performed in the presence or absence of CsA (10 μM) in unstimulated or PDGF-BB (10 ng/ml) stimulated OFs. The HA production of TED OFs (n = 7) and NON-TED OFs (n = 6) were measured by ELISA. The levels of mRNA expressions were examined using RT-PCR. The proliferation rate and metabolic activity were measured by BrdU incorporation and MTT assays, respectively. Treatment with CsA resulted in an average 42% decrease in HA production of OFs (p < 0.0001). CsA decreased the expression levels of HAS2, HAS3 and HYAL2 (p = 0.005, p = 0.005 and p = 0.002, respectively.) PDGF-BB increased HA production (p < 0.001) and HAS2 expression (p = 0.004). CsA could reduce the PDGF-BB-stimulated HA production (p < 0.001) and HAS2 expression (p = 0.005) below the untreated level. In addition, CsA treatment caused a decrease in proliferation potential (p = 0.002) and metabolic activity (p < 0.0001). These findings point to the fact that CsA affects HA metabolism via HAS2, HAS3 and HYAL2 inhibition in OFs. In addition to its well characterized immunosuppressant properties, CsA's beneficial effect in TED may be related to its direct inhibitory effect on basal and growth factor stimulated HA production.

An Appraisal of the Preventive Effect of Statins on the Development of Graves' Ophthalmopathy: A Hospital-Based Cohort Study

INTRODUCTION

Graves' ophthalmopathy (GO) is an autoimmune inflammatory disorder observed in a substantial proportion of patients with Graves' disease (GD), with debilitating symptoms of disfiguring, periorbital pain, dry eyes, diplopia, and even visual disturbances. Previous studies involving Western populations have noted discrepancies in risk factors for GO. Therefore, this study aimed to determine the risk factors for GO development and the protective effect of statins in newly diagnosed patients with GD in Taiwan.

METHODS

This retrospective case-control study was based on a tertiary center cohort involving patients with GD diagnosed between 2010 and 2019 at the National Taiwan University Hospital (n = 11,035). Patients who were diagnosed or treated elsewhere, had been followed up for less than 6 months or were with a diagnosis of orbital tumor were excluded. Overall, 3578 patients with GD met the inclusion criteria. Univariate and multivariate logistic regression analyses were used to ascertain the odds ratio (OR) of developing GO, with adjustment for sociodemographic factors, interventions for managing GD and thyroid hormone levels, to determine protective and risk factors for GO.

RESULTS

In our multivariate model, the use of statins reduced the risk of GO development (OR 0.2; 95% confidence interval [CI] 0.08-0.50; p < 0.001). Thyroid dysfunction including hyperthyroidism (OR 4.2; 95% CI 2.97-5.88; p < 0.001) and hypothyroidism (OR 4.7; 95% CI 3.02-7.19; p < 0.001) was associated with an increased risk of developing GO. Smoking status and lipid profile were not risk factors in our cohort.

CONCLUSION

In newly diagnosed patients with GD, the use of statins decreased the risk of developing GO by 80%, whereas serum lipid levels were not considered risk factors. Further nationwide population-based studies may help clarify the differences in risk factors between various ethnic groups.

TRAIL REGISTRATION

This trial was approved by the Research Ethics Committee of National Taiwan University Hospital (202202066RINC), retrospectively registered from January 1, 2010 to December 31, 2019.

Expression of Collagen XIII in Tissues of the Thyroid and Orbit With Relevance to Thyroid-Associated Ophthalmopathy

Purpose

Antibodies against collagen XIII have previously been identified in patients with active thyroid-associated ophthalmopathy (TAO). Although collagen XIII expression has been described in extraocular muscles and orbital fat, its detailed localization in extraocular and thyroid tissues and the connection to autoimmunity for collagen XIII remain unclear. Our objective was to map the potential targets for these antibodies in the tissues of the orbit and thyroid.

Methods

We evaluated the expression of collagen XIII in human patient and mouse orbital and thyroid tissues with immunostainings and RT-qPCR using Col13a1-/- mice as negative controls. COL13A1 expression in Graves' disease and goiter thyroid samples was compared with TGF-β1 and TNF, and these were also studied in human thyroid epithelial cells and fibroblasts.

Results

Collagen XIII expression was found in the neuromuscular and myotendinous junctions of extraocular muscles, blood vessels of orbital connective tissue and fat and the thyroid, and in the thyroid epithelium. Thyroid expression was also seen in germinal centers in Graves' disease and in neoplastic epithelium. The expression of COL13A1 in goiter samples correlated with levels of TGF-B1. Upregulation of COL13A1 was reproduced in thyroid epithelial cells treated with TGF-β1.

Conclusions

We mapped the expression of collagen XIII to various locations in the orbit, demonstrated its expression in the pathologies of the Graves' disease thyroid and confirmed the relationship between collagen XIII and TGF-β1. Altogether, these data add to our understanding of the targets of anti-collagen XIII autoantibodies in TAO.

Novel insights into the pathogenesis of thyroid eye disease through ferroptosis-related gene signature and immune infiltration analysis

Thyroid eye disease (TED) has brought great physical and mental trauma to patients worldwide. Although a few potential signaling pathways have been reported, knowledge of TED remains limited. Our objective is to explore the fundamental mechanism of TED and identify potential therapeutic targets using diverse approaches. To perform a range of bioinformatic analyses, such as identifying differentially expressed genes (DEGs), conducting enrichment analysis, establishing nomograms, analyzing weighted gene correlation network analysis (WGCNA), and studying immune infiltration, the datasets GSE58331, GSE105149, and GSE9340 were integrated. Further validation was conducted using qPCR, western blot, and immunohistochemistry techniques. Eleven ferroptosis-related DEGs derived from the lacrimal gland were originally screened. Their high diagnostic value was proven, and diagnostic prediction nomogram models with high accuracy and robustness were established by using machine learning. A total of 15 hub gene-related DEGs were identified by WGCNA. Through CIBERSORTx, we uncovered five immune cells highly correlated with TED and found several special associations between these immune cells and the above DEGs. Furthermore, EGR2 from the thyroid sample was revealed to be closely negatively correlated with most DEGs from the lacrimal gland. High expression of APOD, COPB2, MYH11, and MYCN, as well as CD4/CD8 T cells and B cells, was verified in the periorbital adipose tissues of TED patients. To summarize, we discovered a new gene signature associated with ferroptosis that has a critical impact on the development of TED and provides valuable insights into immune infiltration. These findings might highlight the new direction and therapeutic strategies of TED.

Long-term outcomes of inferomedial orbital wall decompression in Graves' ophthalmopathy in an Asian population: A 30-year retrospective study

PURPOSE

This study aims to evaluate the long-term outcomes of inferomedial orbital wall decompression (IMOD) in Graves' ophthalmopathy (GO).

METHODS

A retrospective review of 422 eyes of 226 patients with GO-related cosmetically disfiguring proptosis (COS), dysthyroid optic neuropathy (DON), or exposure keratopathy (EXP) who received IMOD from 1989 to 2020 was conducted. Hertel value (HE) and corrected visual acuity (CVA) were evaluated at baseline and regularly thereafter. Proptosis recurrence, diplopia, and adjuvant surgeries were assessed. Complete success was defined as proptosis reduction over 2 mm without recurrence and improved diplopia. Partial success was defined as proptosis reduction without recurrence but with persistent or new-onset diplopia, and failure as proptosis recurrence.

RESULTS

After follow-up for 40.1 ± 39.6 months (range, 6-239 months), 236 eyes (55.9%) achieved complete success, 175 eyes (41.5%) achieved partial success, and 11 eyes (2.6%) had failure. Significant CVA improvement was observed in both DON and COS groups (P < 0.001 and P = 0.045, respectively). Average proptosis reduction was 5.2 ± 2.2 mm, with a significant increase of 0.5 mm after long-term follow-up (P < 0.001). Incidence of proptosis recurrence was 2.6%. Surgical success rate of COS group was positively correlated with preoperative HE.

CONCLUSION

IMOD demonstrated excellent success rate in all three subgroups with a low proptosis recurrence rate and improved visual outcome in both DON and COS groups. Delayed proptosis reduction effect of IMOD may result in delayed-onset asymmetry, especially in the unilateral group.

How Age Affects Graves' Orbitopathy-A Tertiary Center Study

PURPOSE

Graves' orbitopathy (GO) is an autoimmune disorder leading to inflammation, adipogenesis, and fibrosis. The severity of GO can vary widely among individuals, making it challenging to predict the natural course of the disease accurately, which is important for tailoring the treatment approach to the individual patient. The aim of this study was to compare the clinical characteristics, course, treatment, and prognosis of GO patients under 50 years with older patients.

METHODS

We reviewed the medical records of a random sample of 1000 patients in our GO database Essen (GODE) comprising 4260 patients at our tertiary referral center. Patients were divided into two groups: Group 1 (≤50 years) and Group 2 (>50 years). Only patients with a complete data set were included in the further statistical analysis.

RESULTS

The results showed that younger patients (n = 484) presented significantly more often with mild GO (53% vs. 33%, p < 0.0001), while older patients (n = 448) were more likely to experience moderate-to-severe disease (44% vs. 64%, p < 0.0001). Older patients showed more severe strabismus, motility, and clinical activity scores (5.9 vs. 2.3 PD/310° vs. 330° both p < 0.0001, CAS: 2.1 vs. 1.7, p = 0.001). Proptosis and occurrence of dysthyroid optic neuropathy (DON) showed no significant difference between groups (both 3%). Multiple logistic regression revealed that the need for a second step of eye muscle surgery was most strongly associated with prior decompression (OR = 0.12, 95% CI: 0.1-0.2, p < 0.0001) followed by orbital irradiation and age. The model showed good fitness regarding the area under the curve (AUC = 0.83).

DISCUSSION

In conclusion, younger GO patients present with milder clinical features such as a lower rate of restrictive motility disorders and less pronounced inflammatory signs. Therefore, older patients tend to need more steroids, irradiation, and lid and eye muscle surgery. Still, the risk of DON and the necessity of secondary eye muscle surgery are not or only slightly associated with age, respectively.

Application of artificial intelligence in the assessment of thyroid eye disease (TED) - a scoping review

Background

There is emerging evidence which suggests the utility of artificial intelligence (AI) in the diagnostic assessment and pre-treatment evaluation of thyroid eye disease (TED). This scoping review aims to (1) identify the extent of the available evidence (2) provide an in-depth analysis of AI research methodology of the studies included in the review (3) Identify knowledge gaps pertaining to research in this area.

Methods

This review was performed according to the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (PRISMA). We quantify the diagnostic accuracy of AI models in the field of TED assessment and appraise the quality of these studies using the modified QUADAS-2 tool.

Results

A total of 13 studies were included in this review. The most common AI models used in these studies are convolutional neural networks (CNN). The majority of the studies compared algorithm performance against healthcare professionals. The overall risk of bias and applicability using the modified Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool led to most of the studies being classified as low risk, although higher deficiency was noted in the risk of bias in flow and timing.

Conclusions

While the results of the review showed high diagnostic accuracy of the AI models in identifying features of TED relevant to disease assessment, deficiencies in study design causing study bias and compromising study applicability were noted. Moving forward, limitations and challenges inherent to machine learning should be addressed with improved standardized guidance around study design, reporting, and legislative framework.

Statins in Graves Orbitopathy: A New Therapeutic Tool

PURPOSE

Graves orbitopathy (GO) is the most common extrathyroidal manifestation of Graves disease. Although its pathogenesis is not fully elucidated, GO is commonly considered an autoimmune disease due to loss of self-tolerance against autoantigens shared by thyroid epithelial cells and orbital fibroblasts. High-dose intravenous glucocorticoids (ivGCs) are the most used treatment for moderate-to-severe, active GO, but the addition of other immunomodulating treatments can improve the efficacy of ivGCs. Among the various risk factors that can affect the occurrence of GO, cholesterol may be worthy of interest. Since 2015 the role of cholesterol and cholesterol-lowering medications has been investigated. The purpose of this review is to discuss this topic, thereby offering new therapeutic opportunities for patients with GO.

METHODS

We searched PubMed for studies published between January 1, 1980 and June 1, 2023, using the search terms "Graves orbitopathy," "thyroid eye disease," "Graves ophthalmopathy," "thyroid ophthalmopathy," "thyroid-associated ophthalmopathy," "endocrine ophthalmopathy," "cholesterol," "lipids," "statins," "low-density lipoprotein," "atorvastatin," and "cholesterol-lowering drugs." Only English-language articles were included.

RESULTS

A correlation between low-density lipoprotein cholesterol and the risk of GO development has been reported. Furthermore, low-density lipoprotein cholesterol has been proposed as a risk factor that can affect the course of GO and the response to ivGCs. The protective role of cholesterol-lowering medications in preventing GO has been also investigated. Statin treatment was found to have potential benefits in reducing the risk of GO in patients with Graves disease. Given these findings, measurement of low-density lipoprotein cholesterol and treatment of hypercholesterolemia in patients with moderate-to-severe, active GO may be considered before starting ivGCs administration. Recently, a randomized clinical trial aimed at investigating the effects of statins in GO suggested that the addition of oral atorvastatin to ivGCs improves the overall outcome of moderate-to-severe, active GO in hypercholesterolemic patients given ivGCs.

CONCLUSIONS

Overall, statins seem to have a preventive and therapeutic role in moderate-to-severe active GO. Their efficacy can be related to cholesterol-lowering activity, pleiotropic actions, and interaction with methylprednisolone.

Thyroid Eye Disease and Its Association With Diabetes Mellitus: A Major Review

PURPOSE

Thyroid eye disease (TED) associated with diabetes mellitus (DM) presents unique challenges. DM is a risk factor for TED. Standard management of TED with glucocorticoids (GC), orbital radiation, or teprotumumab can cause adverse events in poor glycemic control. The authors reviewed the literature on the relationship between TED and DM and the management of co-existing diseases.

METHODS

The authors searched PubMed with keywords "thyroid eye disease," "diabetes mellitus," and similar terms from 2013 to 2022. The authors included relevant studies after screening the abstracts. Additional references to the selected studies were included where applicable. Data were extracted from the final articles according to the preplanned outline of the review.

RESULTS

The initial search yielded 279 abstracts. The final review included 93 articles. TED and DM interact at multiple levels-genetic, immunologic, cellular, nutritional, and metabolic. Both DM and thyroid dysfunction exacerbate the morbidity caused by the other. Metabolic factors also affect the inflammatory pathway for TED. Patients with DM develop TED with greater frequency and severity, necessitating interventions for vision salvage. Agents (GC, teprotumumab, or radiation) used for TED are often unsuitable for treatment with DM, especially if there is poor glycemic control or diabetic retinopathy. There were no studies on using steroid-sparing agents in TED with DM.

CONCLUSION

TED and DM co-exist because of multiple intersections in the pathophysiology. Challenges in the treatment include increased TED severity and risk of hyperglycemia and retinopathy. Multidisciplinary teams best undertake treatment of TED with DM.

Current and promising therapies based on the pathogenesis of Graves' ophthalmopathy

Graves' ophthalmopathy (GO) is a hyperthyroidism-related and immune-mediated disease that poses a significant threat to human health. The pathogenesis of GO primarily involves T cells, B cells, and fibroblasts, suggesting a pivotal role for the thyrotropin-antibody-immunocyte-fibroblast axis. Traditional treatment approaches for Graves' disease (GD) or GO encompass antithyroid drugs (ATDs), radioactive iodine, and beta-blockers. However, despite decades of treatment, there has been limited improvement in the global incidence of GO. In recent years, promising therapies, including immunotherapy, have emerged as leading contenders, demonstrating substantial benefits in clinical trials by inhibiting the activation of immune cells like Th1 and B cells. Furthermore, the impact of diet, gut microbiota, and metabolites on GO regulation has been recognized, suggesting the potential of non-pharmaceutical interventions. Moreover, as traditional Chinese medicine (TCM) components have been extensively explored and have shown effective results in treating autoimmune diseases, remarkable progress has been achieved in managing GO with TCM. In this review, we elucidate the pathogenesis of GO, summarize current and prospective therapies for GO, and delve into the mechanisms and prospects of TCM in its treatment.

The phenotype of Graves' orbitopathy is associated with thyrotropin receptor antibody levels

PURPOSE

Graves' orbitopathy (GO) is a specific inflammatory disorder of the orbit characterized by a highly heterogeneous clinical phenotype. The role of thyrotropin receptor antibodies (TSH-R-Ab) has been widely researched, however there is still no evidence that these antibodies have a direct pathogenic role in this pathology. The aim of this study was to examine their relation to the individual clinical features of GO.

METHODS

Ninety-one consecutive patients with GO were recruited. Total antibody concentration (TSH-R binding inhibitory immunoglobulins, TBII) and their functional activity (stimulating TSH-R-Ab, TSAb) were measured using binding immunoassay and cell-based bioassay, respectively.

RESULTS

Both TSAb and TBII levels were significantly associated to the clinical parameters of GO activity. TSAb was a more sensitive serological marker compared to TBII pertaining to eyelid retraction and edema, proptosis, extra-orbital muscle disorders, diplopia, irritable eye symptoms, and photophobia. TSAb, but not TBII, was a significant predictive marker of conjunctival redness, chemosis, caruncle/plica inflammation, eye irritation, and orbital pain, (odds ratio: 3.096, p = 0.016; 5.833, p = 0.009; 6.443, p = 0.020; 3.167, p = 0.045; 2.893, p = 0.032; versus 2.187, p = 0.093; 2.775, p = 0.081; 3.824, p = 0.055; 0.952, p = 0.930; 2.226, p = 0.099, respectively). Neither TSAb nor TBII correlated with the level of proptosis (ρ = 0.259, p = 0.090, and ρ = 0.254, p = 0.104, respectively), however rising TSAb levels were strongly associated to the level of proptosis.

CONCLUSIONS

TSH-R-Ab were significantly associated with GO's phenotype. Especially TSAb, as a sensitive and predictive serological biomarker, can improve diagnosis and management of GO.

TSH receptor autoantibody levels post-total thyroidectomy in Graves' ophthalmopathy: a meta-analysis

BACKGROUND

TSH receptor autoantibodies (TRAbs) are pathognomonic for Graves' disease and are thought to also underly the pathogenesis of Graves' ophthalmopathy (GO). A decline in TRAb levels has been documented post-total thyroidectomy (TTx) in GO, however with conflicting correlations with disease outcomes. The aim of the study was to compare the effectiveness of TTx to other treatment modalities of Graves' disease and examine whether the lowering of TRAbs is associated with GO improvements.

METHOD

We searched electronic databases including Medline, Embase, Scopus, and Web of Science until 31 September 2022 using a broad range of keywords. Patients with GO undergoing TTx with measurements of both TRAbs and progression of the disease using a validated GO scoring system were included. Fourteen studies encompassing data from 1047 patients with GO met our eligibility criteria. The PRISMA guidelines were followed, and five studies had comparable data that were suitable for a meta-analysis.

RESULTS

The Cochrane Risk of Bias tool for RCTs showed low risk of bias across most domains. The pooled odds ratio showed that more patients significantly had normalized TRAb levels post-TTx as compared to other interventions (OR: 1.36, 95% CI: 1.02-1.81, p = 0.035). But, there was no significant difference in GO improvement post-TTx as compared with other intervention groups.

CONCLUSIONS

This meta-analysis shows that TRAb levels may decline largely post-TTx, but may not predict added improvements to the progression of GO. Thus, future studies with uniform designs are required to assess the minimal significant GO improvements.

Potential involvement of the bone marrow in experimental Graves' disease and thyroid eye disease

Introduction

Graves' disease is an autoimmune disorder caused by auto-antibodies against the thyroid stimulating hormone receptor (TSHR). Overstimulation of the TSHR induces hyperthyroidism and thyroid eye disease (TED) as the most common extra thyroidal manifestation of Graves' disease. In TED, the TSHR cross talks with the insulin-like growth factor 1 receptor (IGF-1R) in orbital fibroblasts leading to inflammation, deposition of hyaluronan and adipogenesis. The bone marrow may play an important role in autoimmune diseases, but its role in Graves' disease and TED is unknown. Here, we investigated whether induction of experimental Graves' disease and accompanying TED involves bone marrow activation and whether interference with IGF-1R signaling prevents this activation.

Results

Immunization of mice with TSHR resulted in an increase the numbers of CD4-positive T-lymphocytes (p ≤0.0001), which was normalized by linsitinib (p = 0.0029), an increase of CD19-positive B-lymphocytes (p= 0.0018), which was unaffected by linsitinib and a decrease of GR1-positive cells (p= 0.0038), which was prevented by linsitinib (p= 0.0027). In addition, we observed an increase of Sca-1 positive hematopietic stem cells (p= 0.0007) and of stromal cell-derived factor 1 (SDF-1) (p ≤0.0001) after immunization with TSHR which was prevented by linsitinib (Sca-1: p= 0.0008, SDF-1: p ≤0.0001). TSHR-immunization also resulted in upregulation of CCL-5, IL-6 and osteopontin (all p ≤0.0001) and a concomitant decrease of the immune-inhibitory cytokines IL-10 (p= 0.0064) and PGE2 (p ≤0.0001) in the bone marrow (all p≤ 0.0001). Treatment with the IGF-1R antagonist linsitinib blocked these events (all p ≤0.0001). We further demonstrate a down-regulation of arginase-1 expression (p= 0.0005) in the bone marrow in TSHR immunized mice, with a concomitant increase of local arginine (p ≤0.0001). Linsitinib induces an upregulation of arginase-1 resulting in low arginase levels in the bone marrow. Reconstitution of arginine in bone marrow cells in vitro prevented immune-inhibition by linsitinib.

Conclusion

Collectively, these data indicate that the bone marrow is activated in experimental Graves' disease and TED, which is prevented by linsitinib. Linsitinib-mediated immune-inhibition is mediated, at least in part, by arginase-1 up-regulation, consumption of arginine and thereby immune inhibition.

Non-coding RNA-mediated epigenetic alterations in Grave's ophthalmopathy: A scoping systematic review

Background

It is becoming more and more apparent that Grave's Ophthalmopathy (GO) pathogenesis may be aided by epigenetic processes such as DNA methylation modifications, histone tail covalent modifications, and non-coding RNA (ncRNA)-based epigenetic processes. In the present study, we aimed to focus more on the miRNAs rather than lncRNAs due to lack of investigations on these non-coding RNAs and their role in GO's pathogenesis.

Methods

A six-stage methodology framework and the PRISMA recommendation were used to conduct this scoping review. A comprehensive search was conducted across seven databases to discover relevant papers published until February 2022. The data extraction separately, and quantitative and qualitative analyses were conducted.

Results

A total of 20 articles were found to meet inclusion criteria. According to the results, ncRNA were involved in the regulation of inflammation (miR-146a, LPAL2/miR-1287-5p axis, LINC01820:13/hsa miR-27b-3p axis, and ENST00000499452/hsa-miR-27a-3p axis), regulation of T cell functions (miR-146a/miR-183/miR-96), regulation of glycosaminoglycan aggregation and fibrosis (miR-146a/miR-21), glucocorticoid sensitivity (miR-224-5p), lipid accumulation and adipogenesis (miR-27a/miR-27b/miR-130a), oxidative stress and angiogenesis (miR-199a), and orbital fibroblast proliferation (miR-21/miR-146a/miR-155). Eleven miRNAs (miR-146a/miR-224-5p/miR-Let7d-5p/miR-96-5p/miR-301a-3p/miR-21-5p) were also indicated to have the capacity to be used as biomarkers.

Conclusions

Regardless of the fact that there is significant documentation of ncRNA-mediated epigenetic dysfunction in GO, additional study is needed to thoroughly comprehend the epigenetic connections concerned in disease pathogenesis, paving the way for novel diagnostic and prognostic tools for epigenetic therapies among the patients.

Linsitinib, an IGF-1R inhibitor, attenuates disease development and progression in a model of thyroid eye disease

Introduction

Graves' disease (GD) is an autoimmune disorder caused by autoantibodies against the thyroid stimulating hormone receptor (TSHR) leading to overstimulation of the thyroid gland. Thyroid eye disease (TED) is the most common extra thyroidal manifestation of GD. Therapeutic options to treat TED are very limited and novel treatments need to be developed. In the present study we investigated the effect of linsitinib, a dual small-molecule kinase inhibitor of the insulin-like growth factor 1 receptor (IGF-1R) and the Insulin receptor (IR) on the disease outcome of GD and TED.

Methods

Linsitinib was administered orally for four weeks with therapy initiating in either the early ("active") or the late ("chronic") phases of the disease. In the thyroid and the orbit, autoimmune hyperthyroidism and orbitopathy were analyzed serologically (total anti-TSHR binding antibodies, stimulating anti TSHR antibodies, total T4 levels), immunohistochemically (H&E-, CD3-, TNFa- and Sirius red staining) and with immunofluorescence (F4/80 staining). An MRI was performed to quantify in vivo tissue remodeling inside the orbit.

Results

Linsitinib prevented autoimmune hyperthyroidism in the early state of the disease, by reducing morphological changes indicative for hyperthyroidism and blocking T-cell infiltration, visualized by CD3 staining. In the late state of the disease linsitinib had its main effect in the orbit. Linsitinib reduced immune infiltration of T-cells (CD3 staining) and macrophages (F4/80 and TNFa staining) in the orbita in experimental GD suggesting an additional, direct effect of linsitinib on the autoimmune response. In addition, treatment with linsitinib normalized the amount of brown adipose tissue in both the early and late group. An in vivo MRI of the late group was performed and revealed a marked decrease of inflammation, visualized by ¹⁹F MR imaging, significant reduction of existing muscle edema and formation of brown adipose tissue.

Conclusion

Here, we demonstrate that linsitinib effectively prevents development and progression of thyroid eye disease in an experimental murine model for Graves' disease. Linsitinib improved the total disease outcome, indicating the clinical significance of the findings and providing a path to therapeutic intervention of Graves' Disease. Our data support the use of linsitinib as a novel treatment for thyroid eye disease.

Prognostic significance of thyroid-stimulating hormone receptor antibodies in moderate-to-severe graves' orbitopathy

Design

Retrospective study.

Purpose

The purpose of this retrospective study was to assess the changes in thyroid-stimulating hormone receptor (TSH-R) antibody levels following treatment in patients with moderate-to-severe and active Graves' orbitopathy (GO) and to investigate the correlation between these antibodies and treatment response.

Methods

The subjects of this study comprised of patients newly diagnosed with moderate-to-severe and active GO within the age range of 19 to 79 years. All participants underwent intravenous methylprednisolone (IVMP) therapy for a duration of 12 weeks. Patients with a clinical activity score (CAS) decrease to or less than 3 and no symptom recurrence for at least 3months after the last dose of IVMP were classified as "Group 1". Those with a CAS equal to or greater than 4 were classified as "Group 2". TSH-R antibody levels were measured prior to and following IVMP treatment and treatment response was evaluated after the completion of IVMP therapy. All patients were monitored for a minimum of 6 months post-treatment, with ocular examinations and laboratory tests at the initial visit being included in the analysis.

Results

The medical records of the 96 patients with GO were retrospectively reviewed. Seventy-five patients (78.1%) were response and 21 (21.9%) were non-responsive to IVMP treatment. A higher TSH-R antibody (TRAb) and thyroid-stimulating antibody (TSAb) following treatment were associated with a high risk of no treatment response (P = 0.017; P = 0.047, respectively). TRAb and TSAb levels before treatment were significantly related to TRAb and TSAb levels after treatment (P < 0.001, respectively). The cut-off values for the prediction of poor treatment response of the TRAb and TSAb before and after treatment were 8.305 IU/L, 5.035 IU/L and 449.5%, 361%, respectively (P = 0.027, P =0.001 and P = 0.136, P = 0.004, respectively).

Conclusion

It was observed that elevated levels of TRAb and TSAb prior to IVMP treatment were positively correlated with post-treatment levels of these antibodies. Furthermore, in cases of non-response to IVMP therapy, a diminished decline in both antibodies was observed, and elevated levels of TRAb and TSAb post-treatment were found to be a significant predictor of poor treatment outcome. Measurement of TRAb and TSAb throughout the course of treatment in moderate-to-severe and active cases of GO may offer valuable insights into treatment prognosis and aid in the decision-making process regarding the potential need for increased IVMP dosage or alternative therapeutic strategies.

Influence of biological sex, age and smoking on Graves’ orbitopathy – a ten-year tertiary referral center analysis

Purpose

Severity of Graves’ orbitopathy (GO) shows wide individual differences. For optimal treatment, it is important to be able to predict the natural course of the disease as accurate as possible to counteract with anti-inflammatory and surgical treatment. Therefore, we aimed to further elucidate the impact of sex, age and smoking on GO.

Methods

We collected the clinical and demographic data of all patients of our tertiary referral center from January 2008 till December 2018 and analyzed it with descriptive statistics. Only patients with a complete data set were included in the further analysis. Odds ratio’s for moderate-to-severe and sight-threatening GO in relation to age, sex and smoking were calculated by means of multivariate logistic regression models.

Results

We evaluated the data of 4260 patient with GO and complete data sets. Most of these were women (83%). There were no significant differences between male and female patients regarding smoking habits and thyroid treatment. Men were significantly older at initial manifestation of TED (51.8 vs. 49.9y, p&lt;0.01) and showed significant more often severe stages (61% vs. 53%, p&lt;0.0001). Therefore, they needed significantly more intense treatment with steroids, irradiation, orbital decompression and muscle surgery. In multivariate logistic regression analyses age (OR 0.97, 95% CI:0.97-0.98, p&lt;0.0001), male sex (OR 1.64, 95% CI:1.38-1.9, p&lt;0.0001), smoking (OR 1.19, 95% CI:1.04-1.36, p=0.01), Grave’s disease (OR 1.55, 95% CI:1.26-1.90, p&lt;0.0001) and history of radioiodine treatment (RAI) (OR 2.44, 95% CI:2.10-2.86, p&lt;0.0001) showed an significant association with severe stages of GO.

Discussion

Our retrospective analysis showed once more that women are more often afflicted by GO. In contrast, men seem to be more severely afflicted and in need of anti-inflammatory and surgical treatments. This might be due to a different approach to the health system and resilience to GO specific symptoms, as well as previously described worse thyroid control. Estrogen mediated effects might also play a role as in other autoimmune diseases and should be subject of further trials. Besides the biological sex, smoking could again be confirmed as serious risk factor for severe GO. Of note, RAI was associated with more severe stages of GO, which should be subject to further investigation.

Application of an Interpretable Machine Learning for Estimating Severity of Graves’ Orbitopathy Based on Initial Finding

(1) Background: We constructed scores for moderate-to-severe and muscle-predominant types of Graves’ orbitopathy (GO) risk prediction based on initial ophthalmic findings. (2) Methods: 400 patients diagnosed with GO and followed up at both endocrinology and ophthalmology clinics with at least 6 months of follow-up. The Score for Moderate-to-Severe type of GO risk Prediction (SMSGOP) and the Score for Muscle-predominant type of GO risk Prediction (SMGOP) were constructed using the machine learning-based automatic clinical score generation algorithm. (3) Results: 55.3% were classified as mild type and 44.8% were classified as moderate-to-severe type. In the moderate-to-severe type group, 32.3% and 12.5% were classified as fat-predominant and muscle-predominant type, respectively. SMSGOP included age, central diplopia, thyroid stimulating immunoglobulin, modified NOSPECS classification, clinical activity score and ratio of the inferior rectus muscle cross-sectional area to total orbit in initial examination. SMGOP included age, central diplopia, amount of eye deviation, serum FT4 level and the interval between diagnosis of GD and GO in initial examination. Scores ≥46 and ≥49 had predictive value, respectively. (4) Conclusions: This is the first study to analyze factors in initial findings that can predict the severity of GO and to construct scores for risk prediction for Korean. We set the predictive scores using initial findings.

[Graves' orbitopathy: Current concepts for medical treatment]

BACKGROUND

The therapy of severe manifestations of Graves' orbitopathy (GO) is still a challenge and requires good interdisciplinary cooperation. It is especially important to use stage-adapted anti-inflammatory therapy to avoid irreversible damage.

MATERIAL AND METHODS

Discussion of the latest results of multicentre randomised therapy studies on anti-inflammatory treatments for Graves' orbitopathy, as well as new therapeutic concepts.

RESULTS

Mild cases of GO can be treated with only selenium supplementation and a watchful waiting strategy. In the moderate-to-severe active form of GO, primary therapy consists of i. v. steroids (cumulative 4-5 g) in combination with orbital irradiation in patients with impaired motility. In patients with insufficient therapeutic response after 6 weeks, treatment should be switched to other immunosuppressive agents. In severe sight-threatening disease, bony orbital decompression is usually necessary. As basic research has improved our understanding of the underlying pathophysiology of GO, it has been possible to develop targeted therapies for GO. Teprotumumab, an IGF-1 receptor antibody, was effective in treating GO patients in a phase III trial and should soon be awarded approval for Europe.

CONCLUSION

The current therapy concept for Graves' orbitopathy is as follows: first anti-inflammatory therapy then surgical correction of the permanent defects. This may soon be modified, due to the use of targeted therapies.

The essential role of N6-methyladenosine RNA methylation in complex eye diseases

There are many complex eye diseases which are the leading causes of blindness, however, the pathogenesis of the complex eye diseases is not fully understood, especially the underlying molecular mechanisms of N6-methyladenosine (m6A) RNA methylation in the eye diseases have not been extensive clarified. Our review summarizes the latest advances in the studies of m6A modification in the pathogenesis of the complex eye diseases, including cornea disease, cataract, diabetic retinopathy, age-related macular degeneration, proliferative vitreoretinopathy, Graves' disease, uveal melanoma, retinoblastoma, and traumatic optic neuropathy. We further discuss the possibility of developing m6A modification signatures as biomarkers for the diagnosis of the eye diseases, as well as potential therapeutic approaches.

Discoveries in Thyroid Autoimmunity in the Past Century

This review on the 100th anniversary of the American Thyroid Association summarizes the remarkable progress attained during the past century regarding the pathogenesis and treatment of thyroid autoimmune diseases. Indeed, the general concept of autoimmune diseases in humans was established 70 years ago by thyroid investigators. Graves' disease is a paradigm for the rare occurrence of how autoimmunity can cause disease by stimulating rather than destroying an organ system. Therapeutic advances in the mid 20th century involving administration of thyroid hormones, thionamide drugs, and radioiodine have been hugely beneficial for human health. However, these approaches can only treat, but not cure, thyroid autoimmunity. Investigation of these diseases is facilitated by the identification of a limited number of specific autoantigens, whose molecular cloning has provided much information on their structure. This knowledge has led to highly sensitive and specific diagnostic tests, provided insight into novel aspects regarding the pathogenesis of thyroid autoimmunity, and has opened avenues for the development of new therapeutic agents. Immunotherapy for a cure as opposed to therapy of Graves' disease and Hashimoto's thyroiditis remains the holy grail for the 21st century.

The role and molecular mechanism of gut microbiota in Graves' orbitopathy

PURPOSE

Graves' orbitopathy (GO) is an autoimmune orbital disorder. Gut microbiota dysfunction plays a vital role in autoimmune diseases, including Graves' disease (GD) and GO. In the present study, we aimed to investigate the change of gut microbiota in GD/GO using mouse model.

METHODS

The murine model of GD/GO was established by the challenge of adenovirus expressing thyroid-stimulating hormone (TSH) receptor (TSHR) (Ad-TSHR). The histological changes of orbital and thyroid tissues were analyzed by hematoxylin and eosin (H&E), Masson staining, and immunohistochemistry (IHC) staining. The fecal samples were collected for 16S rRNA gene sequencing and bioinformatics analysis.

RESULTS

The GD/GO model was established successfully, as manifested as the broadened eyelid, exophthalmia and conjunctive redness, severe inflammatory infiltration among thyroid glands and between extraocular muscle space, hypertrophic extraocular muscles, elevated thyroxine (T4) and decreased TSH, and positive CD34, CD40, collagen I, and α-SMA staining. A total of 222 operational taxonomic units (OUTs) were overlapped between mice in the Ad-NC and Ad-TSHR groups. The microbial composition of the samples in the two groups was mainly Bacteroidia and Clostridia, and the Ad-NC group had a significantly lower content of Bacteroidia and higher content of Clostridia. KEGG orthology analysis results revealed differences in dehydrogenase, aspartic acid, bile acid, chalcone synthase, acetyltransferase, glutamylcyclotransferase, glycogenin, and 1-phosphatidylinositol-4-phosphate 5-kinase between two groups; enzyme commission (EC) analysis results revealed differences in several dehydrogenase, oxidase, thioxy/reductase between two groups; MetaCyc pathways analysis results revealed differences in isoleucine degradation, oxidation of C1 compounds, tricarboxylic acid (TCA) cycle IV, taurine degradation, and biosynthesis of paromamine, heme, colonic acid building blocks, butanediol, lysine/threonine/methionine, and histidine/purine/pyrimidine between two groups.

CONCLUSION

This study induced a mouse model of GD/GO by Ad-TSHR challenge, and gut microbiota characteristics were identified in the GD/GO mice. The Bacteroidia and Clostridia abundance was changed in the GD/GO mice. These findings may lay a solid experimental foundation for developing personalized treatment regimens for GD patients according to the individual gut microbiota. Given the potential impact of regional differences on intestinal microbiota, this study in China may provide a reference for the global overview of the gut-thyroid axis hypothesis.

Autophagy in graves' ophthalmopathy

Graves' ophthalmopathy (GO) is an inflammatory autoimmune disease that affects the eyes. It can significantly alter the quality of life in patients because of its distinctive pathological appearance and the effect on vision. To date, the exact pathological mechanism of GO has not been explicitly discovered. However, several studies have associated autophagy with this disease. Autophagy is a catabolic process that helps maintain homeostasis in all organisms by protecting the cells and tissues from various endogenous and exogenous stress factors. Based on our results, patients affected with GO have comparatively elevated levels of autophagy, which critically affects the pathological mechanism of the GO. In this review, we have summarized the autophagy mechanism in the pathogenesis of GO.

Analysis of macular blood flow changes in thyroid associated ophthalmopathy

BACKGROUND

To evaluate the changes in macular superficial retinal vessel density and their relation with visual acuity in thyroid-associated ophthalmopathy (TAO) patients with different severity.

METHODS

This cross-sectional observational study included 70 TAO patients and 70 healthy controls. Only data from the right eyes were analyzed. TAO patients were divided into 7 subgroups according to the NOSPECS score. Foveal avascular zone (FAZ), vascular density (VD), and perfusion density (PD) of macular 1 mm diameter and 6 mm diameter areas were measured by optical coherence tomography angiography (OCTA).

RESULTS

In TAO patients, significant increases were found in macular and foveal vascular densities (FVD) and perfusion densities (FPD) while a significant decrease was found in the FAZ area when compared with the control group (p < 0.05). Spearman correlation analysis and multiple linear regression analysis showed that TAO severity grade was negatively correlated with FVD (β = -1.150, p = 0.032), FPD (β = -0.024, p = 0.042), MVD (β = -0.583, p = 0.020) and MPD (β = -0.011, p = 0.010). Clinical activity score (CAS) score showed positive correlation with FVD (β = 0.794, p = 0.035) and FPD(β = 0.017, p = 0.041). FVD (β = -0.009, p = 0.033), MVD(β = -0.034, p < 0.001), FPD(β = -0.416, p = 0.039) and MPD(β = -2.428, p < 0.001) all showed negative correlation with best corrected visual acuity (BCVA).

CONCLUSIONS

There was an overall increase in superficial macular blood flow in TAO patients compared with healthy controls and the blood flow decreased as TAO got worse. Superficial macular flow density was negatively correlated with BCVA.

The Relationship between Obesity-Related Factors and Graves' Orbitopathy: A Pilot Study

Background and Objectives: The aim of this study was to investigate the relationships between obesity-related factors including body mass index (BMI), diabetes or prediabetes, hyperlipidemia, fasting plasma glucose, fasting plasma insulin, homeostasis model assessment-estimated insulin resistance (HOMA-IR), highly sensitive C-reactive protein (hs-CRP) and Graves' orbitopathy (GO). Materials and Methods: Eighty-four patients with Graves' disease (GD) (42 without GO and 42 with GO) were enrolled in this cross-sectional cohort study. Gender, age, GD treatment history, height, body weight, waist circumference, smoking status, co-morbidities, levels of free thyroxin, thyroid-stimulating hormone, thyroid-stimulating hormone receptor (TSHR) antibodies, fasting plasma glucose and insulin, and hs-CRP were recorded. The eye condition was evaluated using the consensus statement of the European Group of Graves' Orbitopathy (EUGOGO) and the NOSPECS classification. Results: In this study, multivariate regression analysis showed that BMI, fasting plasma insulin, and HOMA-IR were associated with the presence of GO after adjusting the age, gender, smoking, TSHR antibodies, and steroid usage (adjusted odd's ratio (aOR) 1.182, 95% confidence interval (95% CI), 1.003-1.393, p = 0.046; aOR 1.165, 95% CI, 1.001-1.355, p = 0.048; and aOR 1.985, 95% CI, 1.046-3.764, p = 0.036, respectively). In addition, BMI, fasting plasma glucose, fasting plasma insulin, HOMA-IR, and hs-CRP levels were positively correlated with the severity of GO. Conclusions: The findings of this study suggest that obesity-related factors, especially fasting plasma insulin and HOMA-IR, are related to GO. Our study highlighted the importance of obesity-related factors in GO. Obesity-related factors may cause the development of GO or occur simultaneously with GO.

Approach to the Patient: Management and the Long-term Consequences of Graves' Disease in Children

In children, Graves' disease (GD) is the most common cause of hyperthyroidism. Most pediatric patients with GD will not go into lasting remission, even following many years of antidrug therapy. Thus, most pediatric patients will require radioactive iodine (RAI) or surgery. When antithyroid drugs are used, methimazole is the drug of choice. When methimazole is used in children, up to 20% will have minor adverse reactions and serious adverse events occur in up to 1%. RAI is an effective form of therapy when the thyroid size is less than 80 g. Because of concerns of whole-body radiation exposure, it is recommended that RAI be avoided in children under 5 years of age, and dosages less than 10 mCi be used between 5 and 10 years of age. Surgery is an effective treatment in children if performed by a high-volume thyroid surgeon. Because of the scarcity of high-volume pediatric thyroid surgeons, a multidisciplinary approach using pediatric surgeons and endocrine surgeons can be considered. Whereas there is a trend toward long-term antithyroid drug therapy in adults, for several reasons, this approach may not be practical for children. Determining the optimal treatment for the pediatric patient with GD, requires consideration of the risks and benefits relating to age and likelihood of remission.

Integrative metabolic analysis of orbital adipose/connective tissue in patients with thyroid-associated ophthalmopathy

Objective

Thyroid-associated ophthalmopathy (TAO) is a disfiguring autoimmune disease, which destroys the structure of orbital tissues and even threatens vision. Metabolic reprograming is critical in autoimmune diseases; however, the metabolic basis of TAO remains to be clarified. Our study aimed to reveal the metabolic profile of TAO.

Methods

Orbital adipose/connective tissues from eleven TAO patients and twelve control subjects were collected during surgeries and analyzed with liquid chromatograph-mass spectrometer. Orthogonal partial least-squares discrimination analysis (OPLS-DA), variable importance in projection (VIP), heat map, and volcano plot were used to reveal metabolic profile in TAO. Pathway analysis and metabolites-gene analysis were utilized to explore potential metabolic metabolism in TAO.

Results

3038 metabolites were detected in samples from the TAO patients and the controls. OPLS-DA analysis of the metabolomics results showed two distinguished groups, demonstrating that TAO has a unique metabolome. Univariate tests identified 593 dysregulated metabolites (P < 0.05), including 367 increased metabolites and 226 decreased metabolites. Pathway analysis showed that changed metabolites were enriched in cholesterol metabolism, choline metabolism in cancer, fat digestion and absorption, regulation of lipolysis in adipocytes, and insulin resistance. In addition, metabolites-gene analysis illustrated that cholesterol metabolism was involved in the pathogenesis of TAO. Endoplasmic reticulum stress-related genes (ATF6, PERK, and IRE1α) expressions were higher in TAO orbital tissues than in control orbital tissues verified by western blot. Additionally, the expression level of diacylglycerol acyltransferase 1 (DGAT1), a key metabolic protein for triacylglycerol synthesis, was increased in orbital tissues of TAO detected by qRT-PCR, indicating disrupted cholesterol metabolism in TAO.

Conclusion

The present study demonstrated different metabolite profiles and potential metabolic mechanisms in TAO.

Insights into the role of DNA methylation and gene expression in Graves' orbitopathy

CONTEXT

A role of DNA methylation in Graves' orbitopathy (GO) has been proposed. Design. To investigate DNA methylation and gene expression in orbital fibroblasts from control and GO patients, under basal conditions or following challenge with an anti-TSH receptor antibody (M22) or cytokines involved in GO; to investigate the relationship between DNA methylation and cell function (proliferation); to perform a methylome analysis. Setting. Referral Center. Materials. Orbital fibroblasts from six GO and six control patients. Intervention. None. Main Outcome Measure. Methylome analysis of the whole genome. Results. Global DNA methylation increased significantly both in control and GO fibroblasts upon incubation with M22. Expression of two selected genes (CYP19A1 and AIFM2) was variably affected by M22 and interleukin-6. M22 increased cell proliferation in control and GO fibroblasts, which correlated with global DNA methylation. Methylome analysis revealed 19,869 DNA regions differently methylated in GO fibroblasts, encompassing 3,957 genes and involving CpG islands, shores and shelves. One-hundred and nineteen gene families and subfamilies, 89 protein groups, 402 biological processes and seven pathways were involved. Three genes found to be differentially expressed were concordantly hyper- or hypomethylated. Among the differently methylated genes, insulin-like growth factor-1 receptor and several fibroblast growth factors and receptors were included.

CONCLUSIONS

We propose that, when exposed to an autoimmune environment, orbital fibroblasts undergo hyper- or hypomethylation of certain genes, involving CpG promoters, which results in differential gene expression, which may be responsible for functional alterations, in particular higher proliferation, and ultimately for the GO phenotype in vivo.

Mechanisms of immune-related differentially expressed genes in thyroid-associated ophthalmopathy based on the GEO database

Background

We performed a differential analysis, enrichment analysis, and immune-infiltration analysis of the thyroid-associated ophthalmopathy (TAO) gene using data from the Gene Expression Omnibus (GEO) database to provide a theoretical basis for understanding the immune-related mechanisms of TAO.

Methods

We searched the GEO database for “Graves disease” and selected the genes expressed in the lacrimal gland of thyroid-related eye disease patients as the test group and the genes expressed in the lacrimal gland of normal subjects as the control group. Immune-related differentially expressed genes (irDEGs), gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, protein-protein interaction, gene-gene interaction (GGI) network, pivotal gene identification, and immune-infiltration analyses were carried out, and finally, risk-prediction models were constructed.

Results

The GSE105149 and GSE58331 data sets contained 200 DEGs, of which 15 were immune-related. In relation to the GO biological processes (BPs), the main pathways included the interleukin (IL)-27-mediated signaling pathway, the IL-35-mediated signaling pathway, cytokine activity, T helper 17 cell differentiation, the phosphatidylinositol-3-kinase and protein kinase B signaling pathway, cytokine-cytokine receptor interaction, the Janus kinase and signal transducer and activator of transcription signaling pathway, and other KEGG pathways. Cluster of differentiation (CD)4⁺ T cells, monocytes, M0 macrophages, and Mast cells were significantly elevated in TAO, while M2 macrophages were significantly reduced. In the immune cell correlation analysis, CD4⁺ T cells and naïve B cells were significantly positively correlated with activated natural killer (NK) cells, and Mast cells were positively correlated with plasma cells and negatively correlated with M2 macrophages. Risk models for a total of 6 genes (i.e., Janus kinase 1, heat shock protein 90-α, phospholipase A 2 group IIA, fibroblast growth factor 3, glucose-6-phosphate isomerase, and protein disulfide isomerase family A, member 2), were constructed, and over 100 potential targeted therapeutic agents were obtained.

Conclusions

In TAO, various types of immune cells infiltrate to different degrees, and the immune response and inflammatory response are throughout the disease. Our constructed risk-prediction models provide a reference for predicting TAO.

Future Projections in Thyroid Eye Disease

BACKGROUND AND AIMS

This review aims to summarize current and emerging therapies for treatment of thyroid eye disease (TED), in the light of novel understanding of pathogenetic mechanisms, leading to new treatment options and clinical trials.

METHODS

We reviewed and analyzed peer-reviewed literature reporting recent translational studies and clinical trials in the treatment of TED. Searches were made at www.pubmed.gov with keywords "thyroid eye disease," "Graves' ophthalmopathy," "thyroid orbitopathy," and "Graves' orbitopathy."

RESULTS

Surgery is reserved for rehabilitation in chronic TED or for emergent compressive optic neuropathy. Oral and intravenous glucocorticoid therapy has been used for decades with variable efficacy in acute TED, but results may be temporary and side effects significant. Nonsteroidal oral immunosuppressive agents offer modest benefit in TED. Several immunomodulatory monoclonal antibodies, including rituximab and tocilizumab, have shown efficacy for inactivating TED. Recently, teprotumumab, an insulin-like growth factor 1 receptor (IGF-1R) inhibitor, has demonstrated significant improvement in proptosis, clinical activity score, diplopia, and quality of life in patients with active TED, with good tolerability. Newly proposed TED therapies, currently in preclinical and clinical trial phases, include thyroid-stimulating hormone (TSH) receptor inhibitory drugs, RVT-1401, local anti-vascular endothelial growth factor therapy, IGF-1R drugs delivered subcutaneously and orally, and desensitization to the TSH receptor with modified TSH receptor peptides.

CONCLUSION

New, albeit incomplete, understanding of the molecular mechanisms of TED has led to new promising therapies and offered improved outcomes in TED patients. Their full role and their relationship to classical immune suppression should be clarified over the next few years.

Intraocular pressure improvement in patients receiving teprotumumab for the treatment of thyroid eye disease: a case series

BACKGROUND

Teprotumumab is a novel treatment that reduces inflammation and symptoms caused by thyroid eye disease. There are limited data on teprotumumab's effect on intraocular pressure.

CASE PRESENTATION

We report nine patients diagnosed with thyroid eye disease whose intraocular pressure decreased during teprotumumab treatment for 8 weeks: patient 1, a 67-year-old Hispanic woman; patient 2, an 86-year-old African-American man; patient 3, a 71-year-old Caucasian woman; patient 4, a 72-year-old Hispanic woman; patient 5, a 65-year-old Caucasian woman; patient 6, a 54-year-old Caucasian man; patient 7, a 54-year-old Asian man; patient 8, a 31-year-old Asian woman; patient 9, a 60-year-old Caucasian woman. The diagnosis of thyroid eye disease was based on increased redness, swelling, and excessive tearing; abnormal proptosis, lid retraction, and diplopia measurements were also taken during physical examination. Intraocular pressure in primary, lateral gaze, and upgaze was documented. There was significant (p = 0.0397) improvement of primary gaze eye pressure from pre-teprotumumab infusions (baseline) to completion of the treatment course.

CONCLUSIONS

Teprotumumab significantly decreased the intraocular pressure for patients during the duration of the study. Teprotumumab is a novel medication that is approved for the primary treatment of thyroid eye disease in both acute and chronic thyroid eye disease. Previous treatments used to treat thyroid eye disease include glucocorticoids, radiotherapy, or orbital decompression surgery; however, these treatments all have significant limitations. Teprotumumab is an effective noninvasive alternative for decreasing symptoms of thyroid eye disease and, as shown, also lowers intraocular pressure. However, teprotumumab should not be used as a substitute for glaucoma medications; its ability to lower intraocular pressure may be in addition to lowering periorbital pressure and retro-orbital pressure.

Proptosis is associated with thiol-disulfide in patients with Graves' ophthalmopathy

Objective

Graves' ophthalmopathy (GO) is a vision-threatening finding observed in approximately half of Graves' disease patients. The pathophysiology of GO is unclear, and one of the suspected factors is oxidative stress. In our study, we compared the relationship between proptosis and SH-SS in patients diagnosed with GO.

Methods

In this prospective study, 40 recently diagnosed Graves' disease patients with proptosis, 40 recently diagnosed Graves' disease patients without GO and 30 healthy individuals with similar demographic characteristics were included. Serum thiol-disulfide (SH-SS) measurements were performed. Eye examinations were performed by a single ophthalmologist to check for the presence of GO, and proptosis values were recorded with a Hertel exophthalmometer.

Results

Total SH values were lower in the group with proptosis than in the other groups (p < 0.05). Total and native SH values were lower in patients without proptosis than in the control group (p < 0.05). Total SH, native SH and SS levels were independently associated with proptosis (p < 0.05). According to this analysis, it was found that increasing SS and decreasing total and native SH levels increased the probability of proptosis by 24.4%, 32.7% and 32.4%, respectively.

Conclusion

A decrease in SH, which is a natural antioxidant that protects the body against oxidative stress, and an increase in SS are important signs of oxidative damage. Proptosis and SH-SS are closely related in GO. This may help us detect GO and proptosis in Graves' patients. It can also assist in developing new options for preventing and treating GO.

Imaging of the medial rectus muscle predicts the development of optic neuropathy in thyroid eye disease

Goal of the study was to evaluate bony orbit remodeling and extraocular muscle (EOM) volume in thyroid eye disease (TED) and their role as predicting factors for development of dysthyroid optic neuropathy (DON). Orbital computed tomography of 92 patients with TED with (76 orbits) or without DON (98 orbits) were retrospectively evaluated. Orbits (n = 40) of subjects without TED served as controls. Measurements of the bony orbit as well as EOM volume were incorporated into a generalized linear mixed model to predict DON. The angle of the medial orbital wall was significantly smaller (p < 0.001) in patients with TED (− 2.3 ± 3.6°) compared to patients with TED + DON (1.0 ± 4.1°). Both groups differed significantly from controls (− 4.2 ± 2.7°). Bowing of the medial orbital wall correlated positively with muscle volume (r = 0.564; p < 0.001). Total EOM volume was significantly larger in TED + DON (7.6 ± 2.5cm³) compared to TED only (5.6 ± 3.0cm³; p < 0.001) or controls (2.6 ± 0.5cm³). Multivariate analysis revealed the medial rectus muscle volume (TED: 1.06 ± 0.48cm³ vs. TED + DON: 2.16 ± 0.84cm³) as the strongest predictor, achieving a specifity of 86.7% and a sensitivity of 73.7% in diagnosing DON in univariate analysis. Though characterized by a wide range of variability, increased medial rectus muscle volume is the strongest predictor for DON in our patient cohort with TED when analyzing a single muscle.

Identification of tRNA-Related Fragments and Their Potential Regulatory Effects in Thyroid-Associated Ophthalmopathy

Recently, the potential role of tRNA-related fragments (tRFs) in ophthalmic diseases has been extensively researched. However, systematic studies on the potential regulatory effects of tRFs in thyroid-associated ophthalmopathy (TAO) are lacking. We used high-throughput sequencing techniques to measure expression levels of mRNAs and tRFs in patients with TAO, and the results were verified by real-time quantitative reverse transcription polymerase chain reaction (q-PCR). Next, the potential biological regulatory effect of differentially expressed tRFs was analyzed, and potential downstream target RNAs of differentially expressed tRFs were predicted to explore the potential role of tRFs as therapeutic targets and biomarkers of TAO. A total of 50 tRFs and 361 mRNAs were dysregulated in the TAO group, and tRF5-GluCTC, PMAIP1, HSD17B2 and ATF3 were verified to be significantly differentially expressed in TAO. Our research reveals that several associated pathways likely play a role in the pathogenesis of TAO. By targeting ATF3, HSD17B2 and PMAIP1, tRF5-GluCTC may play a potential role in regulating the orbital fibroblast adipogenic response and fibrotic hyperplasia in patients with TAO.

Serum CYR61 Levels are Associated with Graves' Ophthalmopathy and Smoking in Patients with Graves' Disease

Smoking is a well-known risk factor for Graves' ophthalmopathy (GO) in patients suffering from Graves' disease (GD). Cysteine-rich angiogenic inducer 61 (CYR61), which has multiple physiological functions, has been shown to be associated with GD and GO. In this study, we aimed to investigate the association between smoking and CYR61 concentrations in GD patients with and without GO. Serum CYR61 was measured by ELISA. The association between CYR61 concentration and GO was assessed with binary logistic regression in all patients and in subgroups of smokers and nonsmokers. The Spearman correlation coefficient was used to determine the correlations between CYR61 concentration and clinical parameters. CYR61 levels were significantly higher in GD patients with GO than in patients without GO, in smokers than in nonsmokers and in individuals older than 50 years than in those younger than 50 years. The subgroup of "GO smokers" had the highest CYR61 levels [median (IQR), 119 pg/ml (129.8)], compared with "GO nonsmokers" [84.2 pg/ml (90.8), p=0.04], "no GO smokers" [88.9 pg/ml (109.8), p=0.01] and "no GO nonsmokers" [79.4 pg/ml (129.89), p=0.003]. For each unit increase in CYR61 concentration, the odds of having GO in smokers significantly and independently increased by 1% (OR=1.010; 95% CI: 1.002-1.018, p=0.012). In conclusion, our results indicate that smoking and age increase serum CYR61 levels in patients with GD and GO. The role of CYR61 as a predictor of GO in patients with GD should be evaluated in prospective studies.

Insights into Current Management Strategies for Dysthyroid Optic Neuropathy: A Review

Dysthyroid optic neuropathy (DON) is a potentially sight-threatening eye disease associated with Graves’ orbitopathy (GO). DON is not common in GO patients, reportedly occurring in only about 5% of patients. The pathogenesis of severe DON is considered to involve both muscular nerve strangulation and impaired blood flow. There is some objective grading of physical examination findings and the severity of GO, including a clinical activity score (CAS) and EUropean Group On Graves’ Orbitopathy (EUGOGO), but no specialized protocol completely characterizes DON. Most clinicians have decided that the combination of clinical activity findings, including visual acuity, color vision, and central critical fusion frequency, and radiological findings, including magnetic resonance imaging (MRI), can be used to diagnose DON. MRI has the most useful findings, with T2-weighted and fat-suppressed images using short-tau inversion recovery (STIR) sequences enabling detection of extraocular changes including muscle and/orbital fat tissue swelling and inflammation and, therefore, disease activity. The first-choice treatment for DON is intravenous administration of steroids, with or without radiotherapy. Unfortunately, refractoriness to this medical treatment may indicate the need for immediate orbital decompression within 2 weeks. Especially in the acute phase of DON, thyroid function is often unstable, and the surgeon must always assume the risk of general anesthesia and intra- and post-operative management. In addition, there are currently many possible therapeutic options, including molecular-targeted drugs. The early introduction and combination of these immunomodulators, including Janus kinase inhibitors and insulin-like growth factor-1 receptor antibody (teprotumumab), may be effective for GO with DON. However, this is still under investigation, and the number of case reports is small. It is possible that these options could reduce systemic adverse events due to unfocused glucocorticoid administration. The pathophysiology of DON is not yet fully understood, and further studies of its treatment and long-term visual function prognosis are needed.

Evaluation of peripapillary vascular flow in patients with Thyroid-Associated Ophthalmopathy (TAO) by OCT Angiography

PURPOSE

To evaluate changes in peripapillary vascular blood flow indices (PVBFI) in patients with thyroid-associated ophthalmopathy (TAO) using OCT angiography (OCTA) technology.

METHODS

Patients with TAO and control subjects matched for age and sex were included in the study. Eye examination, Clinical Activity Score (CAS) evaluation and OCTA scan analysis (Topcon ImageNet 6; DRI OCT Triton, Topcon Corporation) were performed. In particular, PVBFI of the superficial capillary plexus (SCP), deep capillary plexus (DCP), outer retina (OR) and choriocapillaris (CC) layers were obtained by OCTA and extracted from 8-bit greyscale OCT images using the ImageJ software package.

RESULTS

Twenty-six patients with TAO (19 females, mean age 54.7 ± 5.2 and 7 males, mean age 51.4 ± 16.3) were compared with 26 healthy subjects (15 females, mean age 48.2 ± 14.1 and 11 males, mean age 53.1 ± 15.2). Both DCP-PVBF and CC-PVBFI were significantly reduced in TAO patients compared to control eyes (28.6 ± 2.1 vs. 29.7 ± 0.93, p = 0.002; 46.5 ± 1.72 vs. 47.2 ± 1.2, p = 0.019 respectively); on the other hand, no statistically significant differences were found in SCP-PVBFI and OR-PVBFI in TAO patients compared to healthy subjects (p > 0.05). Also, CC-PVBFI was associated with elevated values of CAS (p = 0.018) and ROC curve showed that patients with elevated CC-PVBFI were correlated with active TAO (CAS > 3) (p = 0.012).

CONCLUSIONS

TAO disease may be associated with changes in DCP-PVBFI and CC-PVBFI; also, CC-PVBFI seems to correlate with disease activity.

Dihydroartemisinin Exerts Antifibrotic and Anti-Inflammatory Effects in Graves' Ophthalmopathy by Targeting Orbital Fibroblasts

Graves' ophthalmopathy (GO) is a common orbital disease that threatens visual function and appearance. Orbital fibroblasts (OFs) are considered key target and effector cells in GO. In addition, hyaluronan (HA) production, inflammation, and orbital fibrosis are intimately linked to the pathogenesis of GO. In this study, we explored the therapeutic effects of dihydroartemisinin (DHA), an antimalarial drug, on GO-derived, primary OFs. CCK8 and EdU assays were applied to evaluate the antiproliferative effect of DHA on OFs. Wound healing assays were conducted to assess OF migration capacity, while qRT-PCR, western blotting, ELISA, and immunofluorescence were used to determine the expression of fibrosis-related and pro-inflammatory markers in these cells. Moreover, RNA sequencing was conducted to identify differentially expressed genes (DEGs) in DHA-treated OFs, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of DEGs was performed to explore potential mechanisms mediating the antifibrotic effect of DHA on GO-derived OFs. Results showed that DHA dose-dependently inhibited OF proliferation and downregulated, at the mRNA and protein levels, TGF-β1-induced expression of fibrosis markers, including alpha smooth muscle actin (α-SMA) and connective tissue growth factor (CTGF). Furthermore, DHA inhibited TGF-β1 induced phosphorylation of extracellular signal-regulated protein kinase 1/2 (ERK1/2) and signal transducer and activator of transcription 3 (STAT3), which suggested that DHA exerted antifibrotic effects via suppression of the ERK and STAT3 signaling pathways. In addition, DHA suppressed the expression of pro-inflammatory cytokines and chemokines, including IL-6, IL-8, CXCL-1, MCP-1, and ICAM-1, and attenuated HA production induced by IL-1β in GO-derived OFs. In conclusion, our study provides first-time evidence that DHA may significantly alleviate pathogenic manifestations of GO by inhibiting proliferation, fibrosis- and inflammation-related gene expression, and HA production in OFs. These data suggest that DHA may be a promising candidate drug for treatment of GO.

Inflammasome activation as a link between obesity and thyroid disorders: Implications for an integrated clinical management

Obesity is strongly associated with chronic low-grade inflammation. Obese patients have an increased risk to develop thyroid autoimmunity and to became hypothyroid, suggesting a pathogenetic link between obesity, inflammation and autoimmunity. Moreover, type 2 diabetes and dyslipidemia, also characterized by low-grade inflammation, were recently associated with more aggressive forms of Graves' ophthalmopathy. The association between obesity and autoimmune thyroid disorders may also go in the opposite direction, as treating autoimmune hyper and hypothyroidism can lead to weight gain. In addition, restoration of euthyroidism by L-T4 replacement therapy is more challenging in obese athyreotic patients, as it is difficult to maintain thyrotropin stimulation hormone (TSH) values within the normal range. Intriguingly, pro-inflammatory cytokines decrease in obese patients after bariatric surgery along with TSH levels. Moreover, the risk of thyroid cancer is increased in patients with thyroid autoimmune disorders, and is also related to the degree of obesity and inflammation. Molecular studies have shown a relationship between the low-grade inflammation of obesity and the activity of intracellular multiprotein complexes typical of immune cells (inflammasomes). We will now highlight some clinical implications of inflammasome activation in the relationship between obesity and thyroid disease.

Long-term follow-up of surgical treatment of thyroid-associated orbitopathy restrictive strabismus

OBJECTIVE

Thyroid-associated orbitopathy (TAO) is the most frequent cause of extraocular muscle enlargement, with consecutive restrictive strabismus. The main muscles involved are inferior and medial rectus, resulting in horizontal esotropia and/or vertical strabismus. Surgery may either establish or improve binocular single vision. The aim of the present study is to describe long-term follow-up of patients who underwent horizontal or vertical TAO strabismus surgery.

METHODS

This observational retrospective study included 29 patients suffering from either vertical or horizontal TAO strabismus and diplopia, of whom 11 underwent bilateral medial recti muscle recession (Group A) and 18 underwent unilateral inferior rectus muscle recession (Group B). The endpoint of the study was the assessment of changes in deviation angle and diplopia across four time points (baseline, 7 days, 6 months, and 24 months) in each group.

RESULTS

In Group A, the horizontal deviation angle significantly decreased 7 days after intervention (p < 0.001), without modifications overtime. In Group B, both deviation angles in primary and down-gaze position significantly decreased from baseline, both 7 days after surgery (p < 0.001) and at 6 months (p = 0.040). An overcorrection, with an inversion of vertical deviation angle, was observed across the different time points.

CONCLUSIONS

Horizontal TAO strabismus correction leads to significant improvements of deviation angle and diplopia, with a stable undercorrection overtime. Inferior rectus recession leads to more unstable results, with a trend towards overcorrection limited to the first 6 months after surgery.

Primary and secondary superior rectus recessions to correct vertical deviations in Graves' orbitopathy patients

PURPOSE

Patients with vertical strabismus and consecutive diplopia due to Graves' orbitopathy (GO) might need recession of the rectus superior muscle. The aim of this retrospective analysis is to provide dose-effect values and motility analysis for these patients.

METHODS

Dose-effect relations (deviation reduction in primary position per amount of recession in mm), monocular excursions and size of the field of binocular single vision (BSV) were evaluated in three different groups of patients. Group 1 (n = 33) patients with primary fibrosis of superior rectus muscle undergoing recession of the ipsilateral rectus superior, Group 2 (n = 14) superior rectus muscle recession after recession of inferior rectus on the contralateral eye and Group 3 (n = 15) simultaneous ipsilateral superior rectus recession and contralateral inferior rectus muscle recession. Surgery was performed using the dose-effect for inferior rectus recession of 4 prism dioptre (PD,Δ ) reduction/per mm recession and the intraoperative traction test.

RESULTS

Restoration of BSV in the central 20° of gaze could be reached in 88%, 79% and 67% of patients in the three groups, respectively. Restoration of BSV in downgaze (up to 30°) was a little less successful, 79%, 57% and 53%, respectively. The median dose-effect was 3.2Δ reduction/mm recession in Group 1 (Spearman correlation r = 0.75, p < 0.0001) and 3.3Δ /mm in Group 2 (n.s.) and 4Δ /mm in Group 3 (r = 0.67, p = 0.016). The basis for the improvement was the symmetrization of ductions.

CONCLUSION

If superior rectus recession is necessary in GO, higher dosing around 3Δ reduction/per mm recession should be applied. In case of large deviations, combined vertical surgery (inferior rectus and superior rectus contralateral) is required and reasonable (low cyclotorsion). Single-step or two-step procedures lead to similar results.