ABSTRACT
Autoimmune thyroid diseases (AITD) such as Graves' disease (GD) or Hashimoto's thyroiditis (HT) are organ-specific diseases that involve complex interactions between distinct components of thyroid tissue. Here, we use spatial transcriptomics to explore the molecular architecture, heterogeneity and location of different cells present in the thyroid tissue, including thyroid follicular cells (TFCs), stromal cells such as fibroblasts, endothelial cells, and thyroid infiltrating lymphocytes. We identify damaged antigen-presenting TFCs with upregulated CD74 and MIF expression in thyroid samples from AITD patients. Furthermore, we discern two main fibroblast subpopulations in the connective tissue including ADIRF+ myofibroblasts, mainly enriched in GD, and inflammatory fibroblasts, enriched in HT patients. We also demonstrate an increase of fenestrated PLVAP+ vessels in AITD, especially in GD. Our data unveil stromal and thyroid epithelial cell subpopulations that could play a role in the pathogenesis of AITD.
Subject(s)
Antigens, Differentiation, B-Lymphocyte , Graves Disease , Hashimoto Disease , Thyroid Gland , Humans , Graves Disease/pathology , Graves Disease/immunology , Graves Disease/genetics , Graves Disease/metabolism , Thyroid Gland/pathology , Thyroid Gland/metabolism , Hashimoto Disease/pathology , Hashimoto Disease/immunology , Hashimoto Disease/metabolism , Hashimoto Disease/genetics , Antigens, Differentiation, B-Lymphocyte/metabolism , Antigens, Differentiation, B-Lymphocyte/genetics , Fibroblasts/metabolism , Fibroblasts/pathology , Histocompatibility Antigens Class II/metabolism , Histocompatibility Antigens Class II/genetics , Thyroid Epithelial Cells/metabolism , Thyroid Epithelial Cells/pathology , Endothelial Cells/metabolism , Endothelial Cells/pathology , Transcriptome , Myofibroblasts/metabolism , Myofibroblasts/pathology , Stromal Cells/metabolism , Stromal Cells/pathology , Female , Macrophage Migration-Inhibitory Factors , Intramolecular OxidoreductasesABSTRACT
Interleukin-17A (IL-17A) plays a pivotal role in the pathogenesis of Graves' disease (GD), an autoimmune disorder affecting thyroid function, but the detailed regulatory mechanisms remain elusive. Circular RNAs (circRNAs) have emerged as key regulators of IL-17A expression and secretion in autoimmune diseases, yet their specific role in GD, especially within CD4 + T lymphocytes, are not well understood. In this study, a circRNA, circPHF16 (hsa_circ_0090364) was found to be highly expressed in the peripheral blood mononuclear cells and serum of GD patients. In vitro experiments in Jurkat T cells revealed that silencing of circPHF16 suppressed IL-17A expression and secretion, while overexpression of circPHF16 had the opposite effect. Furthermore, bioinformatics analysis demonstrated a circPHF16/miR-378a-3p/IL6ST pathway, in which circPHF16 regulates IL6ST expression, which, in turn, influences IL-17A expression and secretion by interacting with miR-378a-3p. In vivo studies in a mouse model of GD showed similar trends in molecular expression levels, consistent with competitive endogenous RNA interactions. Together the results of the study identify circPHF16 as a potential target in the development of new strategies for GD diagnosis and treatment, and thus, offer a theoretical foundation for clinical therapeutic approaches in GD.
Subject(s)
Graves Disease , Interleukin-17 , MicroRNAs , RNA, Circular , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Circular/genetics , RNA, Circular/metabolism , Humans , Interleukin-17/metabolism , Interleukin-17/genetics , Graves Disease/genetics , Graves Disease/metabolism , Animals , Mice , Jurkat Cells , Male , Female , Gene Expression Regulation , AdultABSTRACT
Purpose: To investigate the relationship between bone turnover markers (BTMs) and thyroid indicators in Graves' disease (GD) and to further assess predictive value of changes in early stage retrospectively. Methods: We studied 435 patients with GD and 113 healthy physical examiners retrospectively and followed up these two groups of patients after 6 months. We investigated the correlations between BTMs and other 15 observed factors, and analyzed the predictive value of FT3 and FT4 before and after treatment (FT3-P/FT3-A, FT4-P/FT4-A) on whether BTMs recovered. Results: The levels of thyroid hormones and BTMs in GD group were significantly higher than those in control group (P < 0.05) and decreased after 6 months of treatment. FT3, W, Ca and ALP were independent factors in predicting the elevation of OST. Duration of disease, FT3, TSH and ALP were independent factors in predicting the elevation of P1NP. Age, duration of disease, TRAb and ALP were independent factors in predicting the elevation of CTX-1. The AUC of FT3-P/FT3-A and FT4-P/FT4-A for predicting OST recovery were 0.748 and 0.705 (P < 0.05), respectively, and the cut-off values were 0.51 and 0.595. There was no predictive value for P1NP and CTX-1 recovery (P > 0.05). Conclusion: BTMs were abnormally elevated in GD and were significantly correlated with serum levels of FT3, FT4, TRAb, Ca, and ALP. FT3 decreased more than 51% and FT4 dropped more than 59.5% after 6 months of treatment were independent predictors for the recovery of BTMs in GD.
Subject(s)
Biomarkers , Bone Remodeling , Graves Disease , Predictive Value of Tests , Humans , Male , Female , Graves Disease/blood , Graves Disease/drug therapy , Graves Disease/metabolism , Adult , Biomarkers/blood , Retrospective Studies , Middle Aged , Thyroid Gland/metabolism , Bone and Bones/metabolism , Thyroid Hormones/blood , Case-Control Studies , Prognosis , Antithyroid Agents/therapeutic use , Thyroxine/blood , Triiodothyronine/blood , Follow-Up StudiesABSTRACT
Adrenocortical carcinoma (ACC) is a rare malignancy originating in the adrenal glands, aldosterone-producing ACC, even rarer. Papillary thyroid carcinoma (PTC), by contrast, accounts for the majority of thyroid carcinomas. We herein describe the first reported case of a female with comorbidities of aldosterone-producing ACC, PTC, and Graves' Disease(GD). The patient achieved transient clinical remission following adrenalectomy. However, three months later, aldosterone-producing ACC lung metastases emerged. Subsequently, within another three-month interval, she developed thyroid eye disease(TED). The patient died roughly one year after the adrenal operation. Exome sequencing did not reveal associations between aldosterone-producing ACC, PTC, and GD, and the underlying concurrence mechanism has yet to be elucidated. Further research of similar cases are needed to confirm potential links between the three pathologies.
Subject(s)
Adrenal Cortex Neoplasms , Adrenocortical Carcinoma , Aldosterone , Graves Disease , Thyroid Cancer, Papillary , Thyroid Neoplasms , Humans , Female , Thyroid Cancer, Papillary/metabolism , Thyroid Cancer, Papillary/pathology , Thyroid Cancer, Papillary/genetics , Adrenocortical Carcinoma/metabolism , Adrenocortical Carcinoma/pathology , Graves Disease/metabolism , Graves Disease/complications , Graves Disease/pathology , Thyroid Neoplasms/metabolism , Thyroid Neoplasms/pathology , Adrenal Cortex Neoplasms/metabolism , Adrenal Cortex Neoplasms/pathology , Adrenal Cortex Neoplasms/complications , Aldosterone/metabolism , Middle Aged , Adrenalectomy , Fatal OutcomeABSTRACT
Graves' ophthalmopathy (GO), or thyroid eye disease (TED), is the most frequent extrathyroidal manifestation of Graves' disease (GD). Inflammation and subsequent aberrant tissue remodeling with fibrosis are important pathogenesis. There are many proposed mechanisms and molecular pathways contributing to tissue remodeling and fibrosis in GO, including adipogenesis, fibroblast proliferation and myofibroblasts differentiation, oxidative stress, endoplasmic reticulum (ER) stress, hyaluronan (HA) and glycosaminoglycans (GAGs) accumulation in the extracellular matrix (ECM) and new concepts of epigenetics modification, such as histone modification, DNA methylation, non-coding RNAs, and gut microbiome. This review summarizes the current understanding of ECM proteins and associated tissue remodeling in the pathogenesis and potential mediators for the treatment of GO.
Subject(s)
Graves Disease , Graves Ophthalmopathy , Humans , Graves Ophthalmopathy/genetics , Graves Ophthalmopathy/metabolism , Orbit/metabolism , Extracellular Matrix Proteins/genetics , Extracellular Matrix Proteins/metabolism , Fibroblasts/metabolism , Graves Disease/metabolism , FibrosisABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: For numerous years, the Xiehuo Xiaoying decoction (XHXY), a traditional Chinese medicine formula, has demonstrated substantial promise in treating Graves' disease (GD) in clinical settings, showcasing significant potential. However, the therapeutic mechanism and efficacy material basis of XHXY remains obscure. AIM OF THE STUDY: This work aims to investigate the underlying mechanisms and to study the efficacy material basis of XHXY in anti-GD effect using a combination of TMT quantitative proteomics and molecular docking method. MATERIALS AND METHODS: GD model was initiated by administering Ad-TSH289. Subsequently, the mice underwent a four-week regimen that included oral gavage of XHXY at doses of 17 g/kg·d and 34 g/kg·d, along with intraperitoneal injections of Gentiopicroside (GPS). Utilizing the principles of pharmacological chemistry in traditional Chinese medicine, we employed high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (HPLC-QTOF/MS) to discern prescribed prototype composition of XHXY in serum samples from mouse. TMT proteomics research provided evidence of XHXY's putative targets and important pathways in vivo. The binding activity of probable action targets and prototype composition was detected by molecular docking. Finally, Immunohistochemistry (IHC) and TUNEL staining were used to verify the mechanism of XHXY and GPS in anti-GD. RESULTS: XHXY and GPS alleviated GD by ameliorating the pathological changes and reducing thyroxine and TRAb levels. In mouse serum, a total of 31 prototypical XHXY ingredients were detected, and the majority of these components were from monarch and minister medicine. Proteomics study results indicated that the XHXY may mainly regulate targets including FAS-associated death domain protein (FADD), Apolipoprotein C-III, etc. and main pathways are Apoptosis, Cholesterol metabolism, TNF signalling pathway, etc. Strong binding activity of the prototypical active ingredient and GPS towards FADD, Caspase 8, and Caspase 3 was demonstrated by molecular docking. XHXY and its primary component, GPS, elevated the expression of FADD, Caspase 8, and Caspase 3, and enhance apoptosis in thyroid cells, as lastly validated by TUNEL and IHC staining. CONCLUSIONS: XHXY exhibits a favorable therapeutic effect in treating GD by promoting apoptosis in thyroid cells through the upregulation of FADD, Caspase 8, and Caspase 3 expression. And GPS is the main efficacy material basis for its therapeutic effect in anti-GD.
Subject(s)
Drugs, Chinese Herbal , Graves Disease , Animals , Mice , Caspase 3/metabolism , Caspase 8/metabolism , Molecular Docking Simulation , Proteomics , Graves Disease/drug therapy , Graves Disease/metabolism , Apoptosis , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic useABSTRACT
Background: Graves' disease (GD) and Graves' orbitopathy (GO) result from ongoing stimulation of the TSH receptor due to autoantibodies acting as persistent agonists. Orbital pre-adipocytes and fibroblasts also express the TSH receptor, resulting in expanded retro-orbital tissue and causing exophthalmos and limited eye movement. Recent studies have shown that GD/GO patients have a disturbed gut microbiome composition, which has been associated with increased intestinal permeability. This study hypothesizes that enhanced intestinal permeability may aggravate orbital inflammation and, thus, increase myofibroblast differentiation and the degree of fibrosis. Methods: Two distinct cohorts of GO patients were studied, one of which was a unique cohort consisting of blood, fecal, and retro-orbital tissue samples. Intestinal permeability was assessed by measuring serum lipopolysaccharide-binding protein (LBP), zonulin, TLR5, and TLR9 ligands. The influx of macrophages and accumulation of T-cells and myofibroblast were quantified in orbital connective tissue. The NanoString immune-oncology RNA targets panel was used to determine the transcriptional profile of active fibrotic areas within orbital sections. Results: GO patients displayed significantly higher LBP serum concentrations than healthy controls. Within the MicroGO cohort, patients with high serum LBP levels also showed higher levels of zonulin and TLR5 and TLR9 ligands in their circulation. The increased intestinal permeability was accompanied by augmented expression of genes marking immune cell infiltration and encoding key proteins for immune cell adhesion, antigen presentation, and cytokine signaling in the orbital tissue. Macrophage influx was positively linked to the extent of T cell influx and fibroblast activation within GO-affected orbital tissues. Moreover, serum LBP levels significantly correlated with the abundance of specific Gram-negative gut bacteria, linking the gut to local orbital inflammation. Conclusion: These results indicate that GO patients have enhanced intestinal permeability. The subsequent translocation of bacterial compounds to the systemic circulation may aggravate inflammatory processes within the orbital tissue and, as a consequence, augment the proportion of activated myofibroblasts, which actively secrete extracellular matrix leading to retro-orbital tissue expansion. These findings warrant further exploration to assess the correlation between specific inflammatory pathways in the orbital tissue and the gut microbiota composition and may pave the way for new microbiota-targeting therapies.
Subject(s)
Graves Disease , Graves Ophthalmopathy , Humans , Graves Ophthalmopathy/metabolism , Myofibroblasts , Receptors, Thyrotropin , Intestinal Barrier Function , Toll-Like Receptor 5/metabolism , Toll-Like Receptor 9/metabolism , Graves Disease/metabolism , InflammationABSTRACT
Breakdown of tolerance and abnormal activation in B cells is an important mechanism in the pathogenesis of Graves' disease (GD) and high levels of thyroid hormones (THs) can drive the progression of GD. However, the interactions between THs and abnormal activation of B cells in the context of GD are not well understood. The aim of this study was to investigate B cell-activating factor (BAFF) mediating the cross talk between THs and B cells and the possible underlying mechanisms. A high-level triiodothyronine (T3) mouse model was used to verify T3-mediated induction of overexpression of BAFF and B cell abnormal differentiation. The possible promotion of BAFF overexpression in the mice spleen macrophages during polarization to M1 by T3 was also studied. We showed that high levels of T3 can induce BAFF overexpression and lead to abnormal differentiation of B cells in the mice. While the overexpression of BAFF was observed across many tissue types in the mice, high levels of T3 could induce M1 macrophages polarization by IFN (interferon-gamma)-γ in the spleen of the mice, which in turn generated BAFF overexpression. Our findings provide a novel insight into the interactions between the endocrine and immune systems, as well as provide insight into the role of TH in the pathogenesis of GD.
Subject(s)
Graves Disease , Triiodothyronine , Animals , Mice , Triiodothyronine/metabolism , Graves Disease/metabolism , B-Cell Activating Factor/metabolism , Interleukin-4/metabolism , B-Lymphocytes/metabolism , Cell DifferentiationABSTRACT
Background: The main molecular mechanism underlying acute suppression of iodine organification in normal thyroids after an excessive iodine load, that is, the Wolff-Chaikoff effect, is assumed to be suppression of iodine oxidation and iodothyronine synthesis. However, the mechanism underlying chronic antithyroid action of inorganic iodine in Graves' disease is not fully understood. Using a mouse model of Graves' hyperthyroidism, we examined changes in iodothyronine content and gene expression profiles in the thyroid glands after inorganic iodine loading. Materials and Methods: Graves' hyperthyroidism was induced and maintained in BALB/c mice by repeated immunizations of recombinant adenovirus expressing the human thyrotropin (TSH) receptor A-subunit. Hyperthyroid mice were left untreated (GD-C; n = 8) or treated with inorganic iodine for 12 weeks (GD-NaI; n = 8). We used unimmunized BALB/c mice as a control group (n = 10). In each mouse, serum thyroxine (T4) levels were measured with enzyme-linked immunosorbent assay (ELISA) at 4-week intervals. The intrathyroidal iodothyronine content and gene expression levels were, respectively, evaluated by mass spectrometry and RNA sequencing (RNA-seq) at the end of the experimental period. Results: Serum T4 levels in the GD-C group remained higher than in the control group, whereas those in the GD-NaI group declined to normal levels during the experimental period. Intrathyroidal triiodothyronine (T3), reverse T3 (rT3), and T4 contents in the GD-C group were higher than the control group, and rT3 and T4 were further increased in the GD-NaI group. The observed alterations in iodothyronine levels in the thyroid and sera may be explained by altered expression levels of genes for iodothyronine biosynthetic molecules, their transporter, and deiodinases. Conclusion: In this mouse model of hyperthyroidism, higher intrathyroidal accumulation of T4 and reduced gene expression data of iodothyronine transporters in the GD-NaI group suggest that chronic antithyroid action of iodine in Graves' disease involves suppression of hormone secretion.
Subject(s)
Graves Disease , Hyperthyroidism , Iodine , Humans , Thyroxine , Hyperthyroidism/genetics , Triiodothyronine , Graves Disease/genetics , Graves Disease/metabolism , Iodine/metabolism , Receptors, Thyrotropin , Triiodothyronine, Reverse , Gene ExpressionABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Xiehuo Xiaoying decoction (XHXY) has shown great potential in the treatment of GD, but its mechanism remains obscure. Increase of follicular helper T (Tfh) cells and reduction of follicular regulatory T (Tfr) cells contribute to a high thyrotropin receptor antibodies (TRAb) level and possible Graves' disease (GD). Oxidative stress (OS) disrupts T helper cell differentiation and aggravates autoimmunity. AIM OF THE STUDY: This study aimed to investigate whether XHXY decoction can ameliorate autoimmunity in GD via inhibiting OS and regulating Tfh and Tfr cells. MATERIALS AND METHODS: The main XHXY bioactive compounds were identified using high-performance liquid chromatography quadrupole time-of-flight mass spectrometry. GD was induced in the mice through three intramuscular injections of adenovirus expressing the TSH receptor. Then, the mice received oral gavage of XHXY (17 g/kg·d) and 34 g/kg·d) for 4 weeks. OS indicators were assessed. Flow cytometry was used to confirm the proportion of Tfh and Tfr cells in the lymph nodes and spleens of the mice. Cytokine expression levels were determined using enzyme-linked immunosorbent assay. Factors including interleukin-21, B-cell lymphoma-6, and forkhead box P3 (Foxp3) were detected using quantitative polymerase chain reaction. The mRNA and protein expression levels of Kelch-like ECH-associated protein 1 (Keap1), nuclear factor erythroid-2-related factor 2 (Nrf2), and haem oxygenase 1 (HO-1) were detected using quantitative polymerase chain reaction and Western blotting, respectively. RESULTS: Twelve main ingredients of XHXY were identified. XHXY relieved GD by lowering thyroxine (p < 0.01) and TRAb levels (p < 0.01). XHXY ameliorated OS by decreasing the levels of NADPH oxidase 2 (p < 0.05), 4-hydroxynonenal (p < 0.01), and 8-oxo-2'-deoxyguanosine (p < 0.001). It inhibited Tfh cell expansion (p < 0.05), as well as the production of cytokine interleukin -21 (p < 0.01), interleukin -4 (p < 0.01) and transcription factor B-cell lymphoma 6 (p < 0.05). XHXY also induced Tfr cell amplification (p < 0.05), increased the production of interleukin -10 (p < 0.05) and transforming growth factor ß (p < 0.05) and the mRNA levels of Foxp3 (p < 0.05). Finally, the Tfh/Tfr ratio returned to normal. In addition, XHXY activated Nrf2 and HO-1 expression, but inhibited Keap1 activation. CONCLUSIONS: XHXY relieves autoimmunity in GD via inhibiting Tfh cell amplification and Tfr cell reduction, a mechanism which probably involves the Keap1/Nrf2 signaling pathway.
Subject(s)
Graves Disease , Lymphoma, B-Cell , Animals , Mice , Cytokines/metabolism , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/metabolism , Graves Disease/drug therapy , Graves Disease/metabolism , Interleukins/metabolism , Kelch-Like ECH-Associated Protein 1/metabolism , Lymphoma, B-Cell/metabolism , NF-E2-Related Factor 2/metabolism , RNA, Messenger/metabolism , T Follicular Helper Cells , T-Lymphocytes, Helper-Inducer , T-Lymphocytes, Regulatory , Medicine, Chinese TraditionalABSTRACT
Background: The gut is a target organ of thyroid hormone (TH) that exerts its action via the nuclear thyroid hormone receptor α1 (TRα1) expressed in intestinal epithelial cells. THs are partially metabolized via hepatic sulfation and glucuronidation, resulting in the production of conjugated iodothyronines. Gut microbiota play an important role in peripheral TH metabolism as they produce and secrete enzymes with deconjugation activity (ß-glucuronidase and sulfatase), via which TH can re-enter the enterohepatic circulation. Summary: Intestinal epithelium homeostasis (the finely tuned balance between cell proliferation and differentiation) is controlled by the crosstalk between triiodothyronine and TRα1 and the presence of specific TH transporters and TH-activating and -inactivating enzymes. Patients and experimental murine models with a dominant-negative mutation in the TRα exhibit gross abnormalities in the morphology of the intestinal epithelium and suffer from severe symptoms of a dysfunctional gastrointestinal tract. Over the past decade, gut microbiota has been identified as an essential factor in health and disease, depending on its compositional and functional profile. This has led to a renewed interest in the so-called gut-thyroid axis. Disruption of gut microbial homeostasis (dysbiosis) is associated with autoimmune thyroid disease (AITD), including Hashimoto's thyroiditis, Graves' disease, and Graves' orbitopathy. These studies reviewed here provide new insights into the gut microbiota roles in thyroid disease pathogenesis and may be an initial step toward microbiota-based therapies in AITD. However, it should be noted that cause-effect mechanisms remain to be proven, for which prospective cohort studies, randomized clinical trials, and experimental studies are needed. Conclusion: This review aims at providing a comprehensive insight into the interplay between TH metabolism and gut homeostasis.
Subject(s)
Intestinal Mucosa , Thyroid Hormones , Animals , Humans , Mice , Graves Disease/metabolism , Graves Ophthalmopathy/metabolism , Hashimoto Disease/metabolism , Thyroid Hormones/metabolism , Intestinal Mucosa/metabolism , Gastrointestinal MicrobiomeABSTRACT
PURPOSE: Vitamin D and osteoporosis in Graves' disease (GD) have been examined in cross-sectional studies with divergent results. Here, we prospectively studied vitamin D metabolism and bone health in patients with newly diagnosed GD. METHODS: Thirty consecutive patients with de novo overt thyrotoxicosis diagnosed with GD were included. At diagnosis, none of the patients were treated with vitamin D or anti-osteoporotic drugs. All patients were initially treated with antithyroid drugs. Blood samplings were taken at baseline and at 6 weeks, 3, 6, 12 and 24 months after treatment start. Serum levels of 25OHD3, 1,25OH2D3, calcium, parathyroid hormone (PTH), and C-terminal telopeptides of Type I collagen (CTX-I) were analysed. Bone mineral density (BMD) was measured at baseline, and 1 and 2 years after treatment initiation. RESULTS: At diagnosis, patients with GD did not have vitamin D deficiency. There were no significant correlations between levels of 25OHD3 and thyrotoxicosis. Upon treatment of the thyrotoxicosis, serum calcium fell transiently, and PTH and 1,25OH2D3 increased. 25OHD3 fell within the normal range and stabilised at 6 months. CTX-I fell over 12 months, BMD increased significantly up to 2 years, p = 0.002, < 0.001 and 0.005 in the spine, left total hip and left femoral neck, respectively. CONCLUSIONS: The present data underline that thyrotoxicosis has a negative impact on bone health and demonstrate fine-tuned dynamics in bone and vitamin D metabolism. Upon treatment, bone health improved over a follow-up period of 24 months despite rising PTH. Increased conversion of 25OHD3 to 1,25OH2D3 occurs during treatment of GD.
Subject(s)
Graves Disease , Thyrotoxicosis , Vitamin D Deficiency , Humans , Vitamin D , Prospective Studies , Calcium , Cross-Sectional Studies , Parathyroid Hormone , Bone Density , Calcifediol , Vitamins/therapeutic use , Graves Disease/complications , Graves Disease/drug therapy , Graves Disease/metabolism , Vitamin D Deficiency/complicationsABSTRACT
GPR15 plays an important role in lymphocyte homing and is a key immune molecule to maintain organ immune homeostasis. Yet, no study on the association between GPR15 and Graves' disease (GD) is available. In this study, we systematically investigated the expression of GPR15 in different types of immune cells and different tissues of GD patients. We found that the expressions of GPR15 and GPR15L in peripheral blood of GD patients were increased compared with those in healthy controls. A flow cytometry analysis showed that GPR15 positive cells were mainly CD14+ monocytes and CD56+ natural killer cells (NK cells) of innate immunity, T helper cells and cytotoxic T cells of adaptive immunity. We also found that the expressions of GPR15 and GPR15L in the PBMC of GD patients were positively correlated with the Tfh-specific cytokines IL21 and IL4. In addition, immunohistochemistry showed that the level of GPR15 in thyroid tissue of GD patients was higher than that of the control group. Our results demonstrate for the first time that GPR15 is highly expressed in various immune cells in GD patients, suggesting that GPR15-GPR15L is associated with the activation and infiltration of proinflammatory immune cells in the thyroid tissue of GD patients.
Subject(s)
Graves Disease , Leukocytes, Mononuclear , Humans , Leukocytes, Mononuclear/metabolism , Graves Disease/metabolism , T-Lymphocytes, Helper-Inducer , Killer Cells, Natural , Receptors, Peptide , Receptors, G-Protein-Coupled/genetics , Receptors, G-Protein-Coupled/metabolismABSTRACT
BACKGROUND: Graves' disease (GD) is an autoimmune thyroid disorder and recent studies have proposed a role for interleukin (IL)-37, IL-38, and vitamin D (VitD) in the pathophysiology of disease. Therefore, this study investigated the expression of IL-37, IL-38, and VitD in the serum of GD patients and correlations of their levels with some demographic and clinical characteristics. METHODS: Serum IL-37, IL-38, and VitD levels were evaluated in 90 women with GD and 93 control women using enzyme-linked immunosorbent assay kits. Depending on therapy, six patients were newly diagnosed (ND; untreated), and 50 patients were receiving only carbimazole (CMZ), while 34 patients were also on CMZ but also received one (31 patients), two (one patient), or three (two patients) doses of radioactive iodine (RAI). RESULTS: IL-37 levels were significantly higher in GD patients than in controls, while IL-38 and VitD levels were significantly decreased. As indicated by the area under the curve (AUC), receiver operating characteristic curve analysis demonstrated the potential of IL-37, IL-38, and VitD as biomarkers to distinguish GD patients from controls (AUC = 0.953, 0.959, and 0.793, respectively). Multinomial logistic regression analysis showed that altered levels of IL-37, IL-38, and VitD were most likely associated with the pathogenesis of GD. IL-37 was negatively correlated with IL-38 and VitD, while IL-38 and VitD were positively correlated. CONCLUSION: Serum Il-37 levels were upregulated in women with GD, while IL-38 and VitD levels showed downregulated levels. The latter two were positively correlated while they showed a negative correlation with IL-37.
Subject(s)
Graves Disease , Interleukins , Thyroid Neoplasms , Vitamin D , Female , Humans , Graves Disease/diagnosis , Graves Disease/metabolism , Interleukins/blood , Interleukins/chemistry , Iodine Radioisotopes , Vitamin D/blood , Vitamin D/chemistry , VitaminsABSTRACT
Thyroid eye disease (TED) is a poorly understood autoimmune manifestation of thyroid diseases most commonly associated with Graves' disease. Due to a lack of specific biomarkers and uncertain signs and symptoms, Graves' orbitopathy (GO) is challenging to diagnose early and treat effectively. Nowadays, there is great interest in searching for precise molecular biomarkers for early detection, disease monitoring, and clinical management. Researchers are keen to identify novel methods to predict and diagnose diseases and to monitor patient therapeutic response. Tears, due to their direct contact with the eye and the fact that lacrimal glands can also be affected by the disease, could give new insights into the mechanisms taking place in thyroid-associated orbitopathy (TAO) and reveal potential promising biomarkers. Tear fluid offers the possibility of the non-invasive acquisition of a sample with a high protein content, thereby attracting continuously growing interest in the discovery of novel biomarkers. This article provides an up-to-date overview of the various putative tear-fluid biomarkers that have been identified. In this review, we present the potential use of tears as a diagnostic fluid and tool to investigate the mechanism of ocular diseases and discuss the future research directions in this area.
Subject(s)
Graves Disease , Graves Ophthalmopathy , Humans , Graves Ophthalmopathy/diagnosis , Graves Ophthalmopathy/metabolism , Graves Ophthalmopathy/therapy , Tears/metabolism , Graves Disease/complications , Graves Disease/diagnosis , Graves Disease/metabolism , Biomarkers/metabolism , Eye/metabolismABSTRACT
Thyroid-stimulating hormone (TSH), through activation of its G-protein-coupled thyrotropin receptor (TSHR), controls the synthesis of thyroid hormone-an essential metabolic hormone1-3. Aberrant signalling of TSHR by autoantibodies causes Graves' disease (hyperthyroidism) and hypothyroidism, both of which affect millions of patients worldwide4. Here we report the active structures of TSHR with TSH and the activating autoantibody M225, both bound to the allosteric agonist ML-1096, as well as an inactivated TSHR structure with the inhibitory antibody K1-707. Both TSH and M22 push the extracellular domain (ECD) of TSHR into an upright active conformation. By contrast, K1-70 blocks TSH binding and cannot push the ECD into the upright conformation. Comparisons of the active and inactivated structures of TSHR with those of the luteinizing hormone/choriogonadotropin receptor (LHCGR) reveal a universal activation mechanism of glycoprotein hormone receptors, in which a conserved ten-residue fragment (P10) from the hinge C-terminal loop mediates ECD interactions with the TSHR transmembrane domain8. One notable feature is that there are more than 15 cholesterols surrounding TSHR, supporting its preferential location in lipid rafts9. These structures also highlight a similar ECD-push mechanism for TSH and autoantibody M22 to activate TSHR, therefore providing the molecular basis for Graves' disease.
Subject(s)
Immunoglobulins, Thyroid-Stimulating , Receptors, Thyrotropin , Thyrotropin , Graves Disease/immunology , Graves Disease/metabolism , Humans , Immunoglobulins, Thyroid-Stimulating/immunology , Membrane Microdomains , Receptors, LH , Receptors, Thyrotropin/agonists , Receptors, Thyrotropin/chemistry , Receptors, Thyrotropin/immunology , Receptors, Thyrotropin/metabolism , Thyrotropin/metabolismABSTRACT
Thyroid hormones are vital in metabolism, growth and development1. Thyroid hormone synthesis is controlled by thyrotropin (TSH), which acts at the thyrotropin receptor (TSHR)2. In patients with Graves' disease, autoantibodies that activate the TSHR pathologically increase thyroid hormone activity3. How autoantibodies mimic thyrotropin function remains unclear. Here we determined cryo-electron microscopy structures of active and inactive TSHR. In inactive TSHR, the extracellular domain lies close to the membrane bilayer. Thyrotropin selects an upright orientation of the extracellular domain owing to steric clashes between a conserved hormone glycan and the membrane bilayer. An activating autoantibody from a patient with Graves' disease selects a similar upright orientation of the extracellular domain. Reorientation of the extracellular domain transduces a conformational change in the seven-transmembrane-segment domain via a conserved hinge domain, a tethered peptide agonist and a phospholipid that binds within the seven-transmembrane-segment domain. Rotation of the TSHR extracellular domain relative to the membrane bilayer is sufficient for receptor activation, revealing a shared mechanism for other glycoprotein hormone receptors that may also extend to other G-protein-coupled receptors with large extracellular domains.
Subject(s)
Cryoelectron Microscopy , Immunoglobulins, Thyroid-Stimulating , Receptors, Thyrotropin , Thyrotropin , Cell Membrane/metabolism , Graves Disease/immunology , Graves Disease/metabolism , Humans , Immunoglobulins, Thyroid-Stimulating/chemistry , Immunoglobulins, Thyroid-Stimulating/immunology , Immunoglobulins, Thyroid-Stimulating/pharmacology , Immunoglobulins, Thyroid-Stimulating/ultrastructure , Phospholipids/metabolism , Protein Domains , Receptors, G-Protein-Coupled/agonists , Receptors, G-Protein-Coupled/chemistry , Receptors, G-Protein-Coupled/ultrastructure , Receptors, Thyrotropin/agonists , Receptors, Thyrotropin/chemistry , Receptors, Thyrotropin/immunology , Receptors, Thyrotropin/ultrastructure , Rotation , Thyrotropin/chemistry , Thyrotropin/metabolism , Thyrotropin/pharmacologyABSTRACT
Thyroid hormones (TH), adiponectin and brown adipose tissue (BAT) are regulators of energy homoeostasis. Influence of BAT activity on the relationship between TH and adiponectin remains unexplored. The aim of the study was to identify the relationship between TH and adiponectin and to clarify the impact of active BAT on the metabolic effects of adiponectin before and after the correction of thyrotoxicosis. Twenty-one patients with newly diagnosed hyperthyroidism from Graves' disease were recruited. A titration dosing regimen of thionamide anti-thyroid drug (ATD) was used to establish euthyroidism over 12-24 weeks. Anthropometric, biochemical and adipocytokine parameters were measured before and after control of hyperthyroidism. BAT activity was quantified by fusion 18 F-fluorodeoxyglucose (18 F-FDG) PET/MR imaging, and patients were grouped based on BAT status. Plasma adiponectin level was significantly increased following correction of hyperthyroidism in the overall sample. Free thyroxine (FT4) was also identified as a predictor of adiponectin level in thyroid dysfunction. However, significant changes in adiponectin level and correlations involving adiponectin were absent in BAT-positive patients but maintained in BAT-negative patients. BAT activity diminishes the correlative relationship with body composition and abolishes TH and adiponectin relationships when transitioning from a hyperthyroid to euthyroid state.
Subject(s)
Graves Disease , Hyperthyroidism , Adiponectin/metabolism , Adipose Tissue/metabolism , Adipose Tissue, Brown/metabolism , Fluorodeoxyglucose F18/metabolism , Fluorodeoxyglucose F18/therapeutic use , Graves Disease/drug therapy , Graves Disease/metabolism , Humans , Hyperthyroidism/drug therapy , Hyperthyroidism/metabolism , Thyroid Hormones/metabolismABSTRACT
Cytokines are known to perturb thyroid function and the role of interleukin-4 (IL-4) in the pathogenesis of Graves disease (GD) remains controversial. In our mouse model overexpressing IL-4 in thyrocytes (Thyr-IL4), we have reported that adult mice preserved normal serum thyroxine despite an iodide uptake defect. In the present work, we evaluated if iodine restriction could uncover the thyroid deficiency in Thyr-IL4 animals as well as the role of pendrin overexpression as a compensatory mechanism. Moreover, using an experimental model of GD we investigated the effect of a local expression of IL-4 on the incidence of hyperthyroidism. Thyr-IL4 mice developed more rapidly elevated serum thyrotropin under low-iodine supply with thyroid enlargement and classical histological modifications. These hallmarks of hypothyroidism were all enhanced in Thyr-IL4 mice with complete pendrin invalidation. Following immunization, a lower proportion of Thyr-IL4 animals developed hyperthyroidism. Surprisingly, immunized Thyr-IL4 animals presented numerous leukocyte infiltrates, associated with increased intrathyroidal expression of IFN-γ. We have demonstrated that thyroid deficiency in Thyr-IL4 mice is partially compensated for by the excessive iodide content of the standard chow and the overexpression of pendrin in these animals. Furthermore, we have shown that the local expression of IL-4 in the thyroid attenuates GD progression, which was associated with enhanced thyroid infiltration by immune cells that could negatively affect thyroid function.
Subject(s)
Graves Disease , Hypothyroidism , Interleukin-4 , Iodine , Animals , Graves Disease/genetics , Graves Disease/metabolism , Hyperthyroidism , Interleukin-4/metabolism , Iodides/metabolism , Mice , Sulfate Transporters , Thyroxine/metabolismABSTRACT
BACKGROUND: Several autoimmune and inflammatory disorders, including autoimmune thyroid diseases (AITD), have been linked to Th17 cells and the IL-23/IL-17 axis. Current data suggest that genetic variation contributes greatly to disease susceptibility to AITD. OBJECTIVES: To study the role of single nucleotide polymorphisms (SNPs) of IL-23/IL-17 pathway in AITD predisposition and test the gene-gene/gene-sex interactions in these loci. METHODS: A total of 1051 patients with AITD, including 657 patients with Graves' disease (GD) and 394 patients with Hashimoto's thyroiditis (HT), and 874 healthy controls were enrolled in this case-control association study. Six SNPs were selected and genotyped by multiplex PCR combined with high-throughput sequencing. Interactions were tested by the general multifactor dimensionality reduction (GMDR) method. RESULTS: Allele C and combinational genotype AC+CC of rs3212227 within IL-23 were significantly associated with GD with goiter (p=0.003 and 0.014, respectively). Allele G and combinational genotype AG+GG of rs4819554 within IL-17RA were significantly related to HT with family history and the severity of HT (p=0.011 and 0.027; p=0.041 and 0.035). Also, allele T and genotype CT+TT of rs9463772 within IL-17F were significantly correlated with the severity of HT (p=0.001 and 0.027, respectively). Moreover, high dimensional gene-sex interaction (IL-23R-IL-23-IL-17RA-IL-17F-sex) was identified in AITD, GD, and HT patients with GMDR analysis. CONCLUSIONS: Our study identified the novel loci and gene-sex interaction in AITD. This evidence, from another perspective, suggests that sex, IL-23/IL-17 pathway, and Th17 cells play an important role in the pathogenesis of AITD.