Role of cytokines in the pathogenesis and suppression of thyroid autoimmunity

Cytokine Storm-Induced Thyroid Dysfunction in COVID-19: Insights into Pathogenesis and Therapeutic Approaches

Angiotensin-converting enzyme 2 receptors (ACE2R) are requisite to enter the host cells for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). ACE2R is constitutive and functions as a type I transmembrane metallo-carboxypeptidase in the renin-angiotensin system (RAS). On thyroid follicular cells, ACE2R allows SARS-CoV-2 to invade the thyroid gland, impose cytopathic effects and produce endocrine abnormalities, including stiff back, neck pain, muscle ache, lethargy, and enlarged, inflamed thyroid gland in COVID-19 patients. Further damage is perpetuated by the sudden bursts of pro-inflammatory cytokines, which is suggestive of a life-threatening syndrome known as a "cytokine storm". IL-1β, IL-6, IFN-γ, and TNF-α are identified as the key orchestrators of the cytokine storm. These inflammatory mediators upregulate transcriptional turnover of nuclear factor-kappa B (NF-κB), Janus kinase/signal transducer and activator of transcription (JAK/STAT), and mitogen-activated protein kinase (MAPK), paving the pathway for cytokine storm-induced thyroid dysfunctions including euthyroid sick syndrome, autoimmune thyroid diseases, and thyrotoxicosis in COVID-19 patients. Targeted therapies with corticosteroids (dexamethasone), JAK inhibitor (baricitinib), nucleotide analogue (remdesivir) and N-acetyl-cysteine have demonstrated effectiveness in terms of attenuating the severity and frequency of cytokine storm-induced thyroid dysfunctions, morbidity and mortality in severe COVID-19 patients. Here, we review the pathogenesis of cytokine storms and the mechanisms and pathways that establish the connection between thyroid disorder and COVID-19. Moreover, cross-talk interactions of signalling pathways and therapeutic strategies to address COVID-19-associated thyroid diseases are also discussed herein.

A Review of Pathophysiology and Therapeutic Strategies Targeting TGF-β in Graves' Ophthalmopathy

TGF-β plays a pivotal role in the pathogenesis of GO by promoting orbital tissue remodeling and fibrosis. This process involves the stimulation of orbital fibroblasts, leading to myofibroblast differentiation, increased production of inflammatory mediators, and hyaluronan accumulation. Studies have elucidated TGF-β's role in driving fibrosis and scarring processes through both canonical and non-canonical pathways, particularly resulting in the activation of orbital myofibroblasts and the excessive accumulation of extracellular matrix. Additionally, recent in vitro and in vivo studies have been summarized, highlighting the therapeutic potential of targeting TGF-β signaling pathways, which may offer promising treatment interventions for GO. This review aims to consolidate the current understanding of the multifaceted role of TGF-β in the molecular and cellular pathophysiology in Graves' ophthalmopathy (GO) by exploring its contributions to fibrosis, inflammation, and immune dysregulation. Additionally, the review investigates the therapeutic potential of inhibiting TGF-β signaling pathways as a strategy for treating GO.

Multi-regulatory potency of USP1 on inflammasome components promotes pyroptosis in thyroid follicular cells and contributes to the progression of Hashimoto's thyroiditis

BACKGROUND

Inflammatory diseases are often initiated by the activation of inflammasomes triggered by pathogen-associated molecular patterns (PAMPs) and endogenous damage-associated molecular patterns (DAMPs), which mediate pyroptosis. Although pyroptosis resulting from aberrant inflammasome triggering in thyroid follicular cells (TFCs) has been observed in Hashimoto's thyroiditis (HT) patients, the underlying mechanisms remain largely unknown. Given the extensive involvement of protein ubiquitination and deubiquitination in inflammatory diseases, we aimed to investigate how deubiquitinating enzymes regulate thyroid follicular cell pyroptosis and HT pathogenesis.

METHODS

Our study specifically investigated the role of Ubiquitin-specific peptidase 1 (USP1), a deubiquitinase (DUB), in regulating the inflammasome components NLRP3 and AIM2, which are crucial in pyroptosis. We conducted a series of experiments to elucidate the function of USP1 in promoting pyroptosis associated with inflammasomes and the progression of HT. These experiments involved techniques such as USP1 knockdown or inhibition, measurement of key pyroptosis indicators including caspase-1, caspase-1 p20, and GSDMD-N, and examination of the effects of USP1 abrogation on HT using a mouse model. Furthermore, we explored the impact of USP1 on NLRP3 transcription and its potential interaction with p65 nuclear transportation.

RESULTS

Our findings provide compelling evidence indicating that USP1 plays a pivotal role in promoting inflammasome-mediated pyroptosis and HT progression by stabilizing NLRP3 and AIM2 through deubiquitination. Furthermore, we discovered that USP1 modulates the transcription of NLRP3 by facilitating p65 nuclear transportation. Knockdown or inhibition of USP1 resulted in weakened cell pyroptosis, as evidenced by reduced levels of caspase-1 p20 and GSDMD-N, which could be restored upon AIM2 overexpression. Remarkably, USP1 abrogation significantly ameliorated HT in the mice model, likely to that treating mice with pyroptosis inhibitors VX-765 and disulfiram.

CONCLUSIONS

Our study highlights a regulatory mechanism of USP1 on inflammasome activation and pyroptosis in TFCs during HT pathogenesis. These findings expand our understanding of HT and suggest that inhibiting USP1 may be a potential treatment strategy for managing HT.

Reviving ancient therapeutics in modern medicine: an immunological and biological narrative review of wet cupping in the management of Hashimoto's thyroiditis

Background and Objective

The interwoven immunological, biological, and genetic complexity of thyroid diseases makes suitable targeted therapies particularly challenging to develop. Stemming from ancient practices, al-hijamah, or wet cupping, has achieved notable popularity in recent years, leading to unique applications in modern medicine. By grappling with the current literature that links the effects of wet cupping with the immune system in patients with Hashimoto's thyroiditis (HT), this narrative review aims to compose a comprehensive assessment of this adjunctive treatment based on evidence of its integration into practice.

Methods

Between upregulating critical players of the innate immune system, such as immunostimulatory cytokines, white blood cells (WBCs) and natural killer (NK) cells, and downregulating essential thyroid antibodies (anti-thyroid peroxidase and anti-thyroglobulin) and inflammatory markers (C-reactive protein and erythrocyte sedimentation rate), wet cupping practices provide promising complementary therapy for hypothyroidism.

Key Content and Findings

Wet cupping manipulates in vivo molecular mechanisms, as outlined in hemodynamic and microparticle clearance theories, to slow disease progression and even development in disease-free populations. Given the established utilization of wet cupping in the context of autoimmune diseases and inflammatory conditions, the emerging utility of wet cupping continues to gain credibility.

Conclusions

This literature review illuminates the documented improvements in immune and biological function due to cupping therapeutic practices and sheds light on its appropriate application in the clinical setting for patients with HT. Furthermore, this review proposes a clear need for implementing future clinical trials, which may effectively bridge pathophysiological causes of hypothyroidism with underrated techniques for enhanced thyroid health.

Diagnostic criteria and scoring systems for thyroid storm: An evaluation of their utility - comparative review

A thyroid storm is a life-threatening endocrine emergency characterized by severe hyperthyroidism and many systemic manifestations. Prompt recognition and treatment are essential for patient survival. This study evaluates the utility of existing diagnostic criteria and scoring systems for thyroid storm. A comprehensive literature review encompassed articles published up to December 2023. Various diagnostic criteria and scoring systems, such as the Burch-Wartofsky Point Scale and the Japanese Thyroid Association criteria, were critically assessed based on their sensitivity, specificity, and clinical applicability. Our findings reveal that existing diagnostic criteria and scoring systems, although valuable tools, exhibit limitations. They may lack sensitivity in identifying milder cases of thyroid storm or fail to differentiate it from other critical conditions. Furthermore, some criteria rely heavily on subjective clinical Judgment, which can vary among healthcare providers. Future research should focus on refining existing criteria and developing more objective and universally applicable diagnostic tools to address these limitations. Incorporating advanced laboratory markers and modern imaging techniques may enhance diagnostic accuracy. Additionally, a standardized scoring system approach could improve clinical practice consistency. In conclusion, while current diagnostic criteria and scoring systems provide a foundation for identifying thyroid storm, their utility has shortcomings. Advancements in diagnostic methods and a collaborative effort to establish standardized criteria are imperative to enhance the accuracy and reliability of thyroid storm diagnosis, ultimately improving patient outcomes.

Exploring the bidirectional relationship between metabolic syndrome and thyroid autoimmunity: a Mendelian randomization study

Background

Observational studies have reported a possible association between metabolic syndrome (MetS) and thyroid autoimmunity. Nevertheless, the relationship between thyroid autoimmunity and MetS remains unclear. The objective of this research was to assess the causal impact of MetS on thyroid autoimmunity through the utilization of Mendelian randomization (MR) methodology.

Methods

We performed bidirectional MR to elucidate the causal relationship between MetS and their components and thyroid autoimmunity (positivity of TPOAb). Single nucleotide polymorphisms (SNPs) of MetS and its components were obtained from the publicly available genetic variation summary database. The Thyroidomics Consortium conducted a genome-wide association analysis, which provided summary-level data pertaining to thyroid autoimmunity. The study included several statistical methods, including the inverse variance weighting method (IVW), weighted median, simple mode, weight mode, and MR-Egger methods, to assess the causal link. In addition, to ensure the stability of the results, a sensitivity analysis was conducted.

Results

IVW showed that MetS reduced the risk of developing thyroid autoimmunity (OR = 0.717, 95% CI = 0.584 - 0.88, P = 1.48E-03). The investigation into the causative association between components of MetS and thyroid autoimmune revealed a statistically significant link between triglycerides levels and the presence of thyroid autoimmunity (IVW analysis, OR = 0.603, 95%CI = 0.45 -0.807, P = 6.82E-04). The reverse analysis did not reveal any causal relationship between thyroid autoimmunity and MetS, including its five components.

Conclusions

We have presented new genetic evidence demonstrating that MetS and its triglyceride components may serve as potential protective factors against thyroid autoimmunity.

The association of lymphocyte with hypothyroidism in obstructive sleep apnea

PURPOSE

Obstructive sleep apnea (OSA) is a common sleep-breathing disorder. Numerous investigations have found a strong inherent relationship between OSA and hypothyroidism. Studies suggest that lymphocytes may be involved in the development of hypothyroidism in patients with OSA. This study aimed to assess the association between lymphocytes and hypothyroidism in OSA patients.

PATIENTS AND METHODS

This study involved 920 patients with OSA who underwent nocturnal sleep monitoring, thyroid function testing, and routine blood tests. In patients with OSA, logistic regression analysis indicated independent predictors of hypothyroidism. The cutoff level of lymphocyte count was determined using a receiver operating characteristic (ROC) analysis to predict the occurrence of hypothyroidism in individuals with OSA.

RESULTS

This study comprised 920 OSA patients (617 males and 303 women), 879 with normal thyroid function, and 41 with hypothyroidism, with a hypothyroidism incidence of 4.46%. In the entire OSA population and male OSA patients, the number of lymphocytes was significantly higher in the hypothyroid group than in the control group (p = 0.002 and 0.020, respectively). In addition, among the OSA population younger than 60 years old and patients with mild to moderate OSA, lymphocytes were found to be considerably more in the hypothyroid group than in the euthyroid group. Lymphocyte count, ESS, and sex were all independent predictors of hypothyroidism development in OSA patients. According to ROC curve analysis, the risk of hypothyroidism increases with increasing lymphocyte count in the total patient population, with an optimal diagnostic cutoff point of 2.5 (× 10*9/L).

CONCLUSIONS

The prevalence of hypothyroidism in patients with OSA increases as the number of lymphocytes increases. Lymphocyte count can be used as an independent predictor of the occurrence of hypothyroidism, and it has a diagnostic value for OSA combined with hypothyroidism.

Efficacy and safety of Ophiocordyceps sinensis in the treatment of Hashimoto's thyroiditis: a systematic review and meta-analysis

Objective: To evaluate the efficacy and safety of Ophiocordyceps sinensis (OS) preparations for the treatment of Hashimoto's thyroiditis (HT). Methods: We searched eight databases to collect randomized controlled trials (RCTs) of OS combined with a low-iodine diet or levothyroxine for HT. The search period was from inception to June 2023. Meta-analysis was performed using Revman 5.3 software after two evaluators independently screened the literature, extracted data, and evaluated the risk of bias of the included studies. The GRADE system was used to assess the certainty of evidence. Results: A total of 14 RCTs involving 1,014 patients with HT were included. Meta-analysis showed that OS preparations combined with a low-iodine diet were more effective in reducing thyroid peroxidase antibody (TPOAb) [SMD = -3.81, 95% CI (-5.07, -2.54), p < 0.00001] and thyroglobulin antibody (TgAb) [SMD = -4.73, 95% CI (-6.86, -2.61), p < 0.00001] compared to a low-iodine diet. Compared with levothyroxine treatment alone, OS preparations combined with levothyroxine further reduced TPOAb [SMD = -2.04, 95% CI (-2.82, -1.26), p < 0.00001], TgAb [SMD = -2.01, 95% CI (-2.68, -1.33), p < 0.00001], tumor necrosis factor alpha (TNF-α) [SMD = -3.40, 95% CI (-5.66, -1.14), p = 0.003], interleukin-2 (IL-2) [SMD = -2.31, 95% CI (-3.98, -0.65), p = 0.006], and interleukin-6 (IL-6) [MD = -4.16, 95% CI (-6.17, -2.15), p < 0.0001], and elevated free thyroxine (FT4) [SMD = 1.34, 95% CI (0.59, 2.08), p = 0.0004], but no significant effect on free triiodothyronine (FT3) [SMD = 0.83, 95% CI (-0.12, 1.78), p = 0.09] and thyroid stimulating hormone (TSH) [SMD = -0.80, 95% CI (-1.71, 0.11), p = 0.08]. In terms of safety, three studies reported adverse reactions in 10 patients in each of the experimental and control groups. Conclusion: OS preparations in combination with other treatments (low-iodine diet or levothyroxine) may decrease thyroid autoantibodies and inflammatory responses in patients with HT. In HT patients with hypothyroidism, the combination of the OS preparations with levothyroxine also improved FT4. However, the quality of the included studies was generally low. Moreover, the safety of OS preparations remains unclear. Therefore, more high-quality, multicenter, large-sample RCTs are needed in the future to validate the efficacy and safety of OS preparations. Systematic Review Registration: https://www.crd.york.ac.uk/prospero, identifier CRD42023432663.

Prevalence of autoimmune and inflammatory diseases and mental health conditions among an alopecia areata cohort from a US administrative claims database

Alopecia areata (AA) is associated with an increased burden of autoimmune and inflammatory disease and mental health conditions that may have a negative impact on quality of life. However, the exact burden of comorbidities on US patients with AA and the clinical subtypes alopecia totalis (AT) and alopecia universalis (AU) compared with those without AA is not well understood. This retrospective cohort study aimed to assess the incidence rates and prevalence of AA and its clinical subtypes and examine the autoimmune and inflammatory disease and mental health condition diagnosis burden in US patients with AA and a matched cohort without AA. The Optum Clinformatics Data Mart database was used to select patients aged ≥12 years enrolled between October 1, 2016, and September 30, 2020, who had two or more AA diagnosis codes for the AA cohort. Three patients without AA were age-, sex-, and race-matched to each patient with AA. Autoimmune and inflammatory diseases and mental health conditions were evaluated at baseline and up to 2 years after the index date. In total, 8784 patients with AA (599 with AT/AU) and 26 352 matched patients without AA were included. The incidence rate of AA was 17.5 per 100 000 person-years (PY; AT/AU: 1.1 per 100 000 PY; non-AT/AU: 16.3 per 100 000 PY), and the prevalence was 54.9 per 100 000 persons (AT/AU: 3.8; non-AT/AU: 51.2). Patients with AA had a higher prevalence of autoimmune and inflammatory diseases than the matched non-AA cohort, including allergic rhinitis (24.0% vs 14.5%), asthma (12.8% vs 8.8%), atopic dermatitis (8.3% vs 1.8%), and psoriasis (5.0% vs. 1.6%). The proportions of anxiety (30.7% vs 21.6%) and major depressive disorder (17.5% vs 14.0%) were higher in patients with AA than those without AA. Patients with AT/AU generally had a greater prevalence of autoimmune and inflammatory disease and mental health conditions than patients with non-AT/AU AA.

How does Hashimoto's thyroiditis affect bone metabolism?

Bone marrow contains resident cellular components that are not only involved in bone maintenance but also regulate hematopoiesis and immune responses. The immune system and bone interact with each other, coined osteoimmunology. Hashimoto's thyroiditis (HT) is one of the most common chronic autoimmune diseases which is accompanied by lymphocytic infiltration. It shows elevating thyroid autoantibody levels at an early stage and progresses to thyroid dysfunction ultimately. Different effects exert on bone metabolism during different phases of HT. In this review, we summarized the mechanisms of the long-term effects of HT on bone and the relationship between thyroid autoimmunity and osteoimmunology. For patients with HT, the bone is affected not only by thyroid function and the value of TSH, but also by the setting of the autoimmune background. The autoimmune background implies a breakdown of the mechanisms that control self-reactive system, featuring abnormal immune activation and presence of autoantibodies. The etiology of thyroid autoimmunity and osteoimmunology is complex and involves a number of immune cells, cytokines and chemokines, which regulate the pathogenesis of HT and osteoporosis at the same time, and have potential to affect each other. In addition, vitamin D works as a potent immunomodulator to influence both thyroid immunity and osteoimmunology. We conclude that HT affects bone metabolism at least through endocrine and immune pathways.

The Role of Toll-like Receptor 2 (TLR2) in the Development and Progression of Hashimoto’s Disease (HD): A Case Study on Female Patients in Poland

Chronic lymphocytic thyroiditis, commonly known as HD, is one of the most common thyroid disorders. Due to the diverse factors affecting the etiopathogenesis of this disease (hormonal disorders and genetic and environmental factors), as well as the direct involvement of the immune system, scientists are increasingly willing to undertake research aimed at explaining the impact of the loss of immune tolerance and reactivity of autoantigens on the development of the disease. One of the directions of research in recent years is the role of the innate immune response, particularly Toll-like receptors (TLRs), in the pathogenesis of HD. The purpose of this study was to determine the importance of Toll-like receptor 2 (TLR2) expression on selected populations of immune cells, namely, monocytes (MONs) and dendritic cells (DCs), in the course of HD. Particular attention was paid to the analysis of TLR2’s correlation with clinical parameters and the possibility its use as a potential biomarker molecule in the diagnostic process. Based on the obtained results, we found a statistically significant increase in the percentage of all analyzed populations of immune cells, i.e., mDC BDCA-1+CD19−, pDC BDCA-1+CD123, classical MONs CD14+CD16−, and non-classical MONs CD14+CD16+ showing on their surface TLR2 expression in patients diagnosed with HD compared to the healthy volunteers. Moreover, in the study group, we noted a more than 6-fold increase in the concentration of the soluble form of TLR2 in plasma compared to healthy patients. In addition, the correlation analysis showed significant positive correlations between the level of TLR2 expression on selected subpopulations of immune cells and biochemical indicators of thyroid function. Based on the obtained results, we can assume that TLR2 may be involved in the immunopathogenesis of HD.

Dynamic changes in the histomorphological structure of the thyroid gland of rats against the background of experimental autoimmune thyroiditis

In preclinical studies, which are conducted to study the therapeutic effectiveness and pharmacological safety of biologically active compounds for the correction of autoimmune thyroiditis, various experimental models of this pathology are used in the experiment. In this work, we analyzed various models of thyroiditis that have been used for the past fifty years. Such an analysis made it possible to choose the most optimal model for the study of autoimmune pathology of the thyroid gland as well as for the correction of this condition. The analysis of known and the search for new pathogenetically justified models of autoimmune diseases of endocrine organs is a very urgent task. The aim of the work was to study the dynamics of changes in the histomorphological structure of the thyroid gland when modeling autoimmune thyroiditis in rats using an allogeneic antigen isolated from the human thyroid gland. The postoperative thyroid gland of a person was used as an antigen. Morphological changes in the thyroid gland were studied one, three and six months after the end of the simulation. It was found that the use of this type of immunization led to changes in the parenchyma of the gland, characteristic of autoimmune thyroiditis. Already one month after modeling, Gürtle cells, fibrosis, areas of lymphoid infiltration of the parenchyma were registered. These pathological changes persisted and worsened three and six months after the end of the simulation. The investigated type of model of experimental autoimmune thyroiditis is easily reproduced. Pathological changes in the gland deepen over time and are comparable to those that occur in people with Hashimoto's thyroiditis

Evaluation of Epithelial-Mesenchymal Transition Markers in Autoimmune Thyroid Diseases

A state of chronic inflammation is common in organs affected by autoimmune disorders, such as autoimmune thyroid diseases (AITD). Epithelial cells, such as thyroid follicular cells (TFCs), can experience a total or partial transition to a mesenchymal phenotype under these conditions. One of the major cytokines involved in this phenomenon is transforming growth factor beta (TGF-β), which, at the initial stages of autoimmune disorders, plays an immunosuppressive role. However, at chronic stages, TGF- β contributes to fibrosis and/or transition to mesenchymal phenotypes. The importance of primary cilia (PC) has grown in recent decades as they have been shown to play a key role in cell signaling and maintaining cell structure and function as mechanoreceptors. Deficiencies of PC can trigger epithelial-mesenchymal transition (EMT) and exacerbate autoimmune diseases. A set of EMT markers (E-cadherin, vimentin, α-SMA, and fibronectin) were evaluated in thyroid tissues from AITD patients and controls through RT-qPCR, immunohistochemistry (IHC), and western blot (WB). We established an in vitro TGF-β-stimulation assay in a human thyroid cell line to assess EMT and PC disruption. EMT markers were evaluated in this model using RT-qPCR and WB, and PC was evaluated with a time-course immunofluorescence assay. We found an increased expression of the mesenchymal markers α-SMA and fibronectin in TFCs in the thyroid glands of AITD patients. Furthermore, E-cadherin expression was maintained in these patients compared to the controls. The TGF-β-stimulation assay showed an increase in EMT markers, including vimentin, α-SMA, and fibronectin in thyroid cells, as well as a disruption of PC. The TFCs from the AITD patients experienced a partial transition to a mesenchymal phenotype, preserving epithelial characteristics associated with a disruption in PC, which might contribute to AITD pathogenesis.

A Novel Inflammatory Marker for the Diagnosis of Hashimoto's Thyroiditis: Platelet-Count-to-Lymphocyte-Count Ratio

BACKGROUND

Hashimoto's thyroiditis (HT) is a chronic autoimmune thyroiditis that causes systemic inflammation in the body, leading to hypothyroidism and an enlargement of the thyroid gland.

OBJECTIVES

This study aims to reveal whether there is a relationship between Hashimoto's thyroiditis and the platelet-count-to-lymphocyte-count ratio (PLR), which is used as a new inflammatory marker.

METHODS

In this retrospective study, we compared the PLR of the euthyroid HT group and the hypothyroid-thyrotoxic HT group to the controls. We also evaluated the values of thyroid-stimulating hormone (TSH), free T4 (fT4), C-reactive protein (CRP), aspartate transaminase (AST), alanine transaminase (ALT), white blood cell count, lymphocyte count, hemoglobin, hematocrit, and platelet count in each group.

RESULTS

The PLR of the subjects with Hashimoto's thyroiditis was found to be significantly different from the control group (p < 0.001), with the rankings as follows: hypothyroid-thyrotoxic HT 177% (72-417) > euthyroid HT 137% (69-272) > control group 103% (44-243). In addition to the increased PLR values, an increase in CRP values was also observed, revealing a strong positive correlation between the PLR and CRP in the HT patients.

CONCLUSION

In this study, we found out that the PLR was higher in the hypothyroid-thyrotoxic HT and euthyroid HT patients than in a healthy control group.

Role of Jumonji domain-containing protein D3 and its inhibitor GSK-J4 in Hashimoto's thyroiditis

Hashimoto's thyroiditis (HT) is an autoimmune illness caused by a combination of genetic, epigenetic, and environmental factors. The pathogenesis of HT is not fully elucidated, especially in epigenetics. The epigenetic regulator Jumonji domain-containing protein D3 (JMJD3) has been extensively investigated in immunological disorders. This study has been performed to explore the roles and potential mechanisms of JMJD3 in HT. Thyroid samples from patients and healthy subjects were collected. We first analyzed the expression of JMJD3 and chemokines in the thyroid gland using real-time PCR and immunohistochemistry. In vitro, the apoptosis effect of the JMJD3-specific inhibitor GSK-J4 on the thyroid epithelial cell line Nthy-ori 3-1 was evaluated using FITC Annexin V Detection kit. Reverse transcription-polymerase chain reaction and Western blotting were applied to examine the inhibitory effect of GSK-J4 on the inflammation of thyrocytes. In the thyroid tissue of HT patients, JMJD3 messenger RNA and protein levels were substantially greater than in controls (P < 0.05). Chemokines C-X-C motif chemokine ligand 10 (CXCL10) and C-C motif chemokine ligand 2 (CCL2) were elevated in HT patients, and thyroid cells with stimulation of tumor necrosis factor α (TNF-α). GSK-J4 could suppress TNF-α-induced synthesis of chemokines CXCL10 and CCL2 and prohibit thyrocyte apoptosis. Our results shed light on the potential role of JMJD3 in HT and indicate that JMJD3 may become a novel therapeutic target in HT treatment and prevention.

The Anti-Inflammatory and Immunomodulatory Activities of Natural Products to Control Autoimmune Inflammation

Inflammation is an integral part of autoimmune diseases, which are caused by dysregulation of the immune system. This dysregulation involves an imbalance between pro-inflammatory versus anti-inflammatory mediators. These mediators include various cytokines and chemokines; defined subsets of T helper/T regulatory cells, M1/M2 macrophages, activating/tolerogenic dendritic cells, and antibody-producing/regulatory B cells. Despite the availability of many anti-inflammatory/immunomodulatory drugs, the severe adverse reactions associated with their long-term use and often their high costs are impediments in effectively controlling the disease process. Accordingly, suitable alternatives are being sought for these conventional drugs. Natural products offer promising adjuncts/alternatives in this regard. The availability of specific compounds isolated from dietary/medicinal plant extracts have permitted rigorous studies on their disease-modulating activities and the mechanisms involved therein. Here, we describe the basic characteristics, mechanisms of action, and preventive/therapeutic applications of 5 well-characterized natural product compounds (Resveratrol, Curcumin, Boswellic acids, Epigallocatechin-3-gallate, and Triptolide). These compounds have been tested extensively in animal models of autoimmunity as well as in limited clinical trials in patients having the corresponding diseases. We have focused our description on predominantly T cell-mediated diseases, such as rheumatoid arthritis, multiple sclerosis, Type 1 diabetes, ulcerative colitis, and psoriasis.

Thyroid Dysfunction and COVID-19: The Emerging Role of Selenium in This Intermingled Relationship

COVID-19 represents a worldwide public health emergency, and, beyond the respiratory symptoms characterizing the classic viral disease, growing evidence has highlighted a possible reciprocal relationship between SARS-CoV-2 infection and thyroid dysfunction. The updated data discussed in this review suggests a role of SARS-CoV-2 infection on the thyroid gland, with multiple thyroid pictures described. Conversely, no conclusion can be drawn on the association between pre-existing thyroid disease and increased risk of SARS-CoV-2 infection. In this scenario, selenium (Se), an essential trace element critical for thyroid function and known as an effective agent against viral infections, is emerging as a potential novel therapeutic option for the treatment of COVID-19. Large multicentre cohort studies are required to elucidate the mechanisms underlying thyroid dysfunction during or following recovery from COVID-19, including Se status. Meanwhile, clinical trials should be performed to evaluate whether adequate intake of Se can help address COVID-19 in Se-deficient patients, also avoiding thyroid complications that can contribute to worsening outcomes during infection.

A randomized clinical trial demonstrating cell type specific effects of hyperlipidemia and hyperinsulinemia on pituitary function

Introduction

Obesity is characterized by elevated lipids, insulin resistance and relative hypogonadotropic hypogonadism, reducing fertility and increasing risk of pregnancy complications and birth defects. We termed this phenotype ‘Reprometabolic Syndrome’ and showed that it can be recapitulated by acute infusions of lipid/insulin into healthy, normal weight, eumenorrheic women. Herein, we examined the broader impact of hyperlipidemia and euglycemic hyperinsulinemia on anterior pituitary trophic hormones and their targets.

Methods

Serum FSH, LH, TSH, growth hormone (GH), prolactin (PRL), thyroid hormones (free T4, total T3), cortisol, IGF-1, adiponectin, leptin and creatinine were measured in a secondary analysis of an interventional crossover study of 12 normal weight cycling women who underwent saline and heparin (control) infusion, or a euglycemic insulin infusion with heparin and Intralipid^® (lipid/insulin), between days 2–5 in sequential menstrual cycles.

Results

In contrast to the decrease in gonadotropins, FSH and LH, infusion of lipid/insulin had no significant effects on other trophic hormones; TSH, PRL or GH. Thyroid hormones (fT4 and total T3), cortisol, IGF-1, adiponectin and creatinine also did not differ between saline or lipid/insulin infusion conditions. Leptin increased in response to lipid/insulin (p<0.02).

Conclusion

Acute hyperlipidemia and hyperinsulinemia exerted differential, cell type specific effects on the hypothalamic-pituitary-gonadal, adrenal and thyroid axes. Elucidation of mechanisms underlying the selective modulation of pituitary trophic hormones, in response to changes in diet and metabolism, may facilitate therapeutic intervention in obesity-related neuroendocrine and reproductive dysfunction.

Cytokines in the Immune Microenvironment Change the Glycosylation of IgG by Regulating Intracellular Glycosyltransferases

Background

Changes in IgG glycosylation, as a novel pathological feature, are observed in various autoimmune diseases (AIDs). The glycosylation patterns of IgG play a critical role in regulating the biological function and stability of IgG involved in the pathophysiology of many AIDs. However, the intracellular regulatory mechanisms underlying the effects of disturbances in various cytokines on IgG glycosylation are poorly understood. Thus, we investigated the regulatory effects of elevated cytokines in AIDs on intracellular IgG glycosylation within B cells.

Methods

First, we established a controlled primary culture system in vitro to differentiate human CD19+ B cells into antibody-secreting cells (ASCs). Then, the IgG concentrations in the supernatants were measured by enzyme-linked immunoassay (ELISA) under IFN-γ, TNF-α, IL-21, IL-17A, BAFF, or APRIL stimulation. Next, the glycosylation levels of IgG under different stimuli were compared via a lectin microarray. The fine carbohydrate structures of IgG were confirmed by matrix-assisted laser desorption/ionization-quadrupole ion trap-time of flight-mass spectrometry (MALDI-TOF-MS). Finally, the expression of glycosyltransferases and glycosidases in B cells under stimulation with several cytokines was detected by real-time PCR and western blotting.

Results

We found that cytokines significantly promoted IgG production in vitro and led to considerably different IgG glycan patterns. Specifically, the results of lectin microarray showed the galactose level of IgG was increased by IFN-γ stimulation (p&lt;0.05), and the sialylation of IgG was increased by IL-21 and IL-17A (p&lt;0.05). The MALDI-TOF-MS data showed that the frequency of agalactosylation was decreased by IFN-γ with the increased frequency of mono-galactosylation and decreased frequency of digalactosylation, accompanied by upregulation of β-1,4-galactosyltransferase 1. Both frequencies of mono-sialylated and disialylated N-glycans were increased by IL-21 and IL-17A with decreased frequency of asialylation, and the expression of β-galactoside α-2,6-sialyltransferase 1 was upregulated by IL-21 and IL-17A.

Conclusion

Abnormally elevated cytokines in the microenvironment regulates IgG glycan patterns by regulating intracellular glycosyltransferases in human B cells.

Patients with Autoimmune Thyroid Diseases Have Higher Prevalence of Positive Antiphospholipid Antibodies: A Systematic Review and Meta-Analysis

INTRODUCTION

Autoimmune thyroid diseases (AITDs) and antiphospholipid syndrome (APS) are commonly seen in childbearing-age women and can lead to recurrent miscarriages. Studies with a relatively small sample size were conducted and concluded inconsistent results on the relationship between AITDs and APS or the presence of antiphospholipid (aPL) antibodies. This meta-analysis aimed to provide evidence on the possible association between AITDs and APL using primary data from all relevant studies.

METHODS

Literature databases including PubMed, Embase, and Cochrane were searched from the time when the databases were established to March 2022. A total of 7 studies that met all inclusion criteria were selected in this meta-analysis, with 475 AITD patients and 764 healthy controls. After data extraction, the pooled odds ratio (OR) and the 95% confidence interval (95% CI) were calculated.

RESULTS

The risk of positive APL in AITD patients was approximately 3 folds higher in AITD patients compared with those in healthy controls (OR 3.41, 95% CI 2.29-5.08, p < 0.001). There was no significant association between the risk of Graves' disease (GD) and positive APL (OR 9.3, 95% CI 0.10-824.73, p=0.33). The risk of positive APL in patients with Hashimoto's thyroiditis (HT) increased over 2 folds compared with healthy controls (OR 3.35, 95% CI 1.55-7.23, p=0.002).

CONCLUSIONS

The result of this meta-analysis proved that the presence of APL was significantly increased in patients with AITD compared with healthy individuals, especially in patients with Hashimoto's thyroiditis.

Thyroid function in COVID-19 and the association with cytokine levels and mortality

The hypothalamic-pituitary-thyroid hormone axis might be affected in COVID-19, but existing studies have shown varying results. It has been hypothesized that hyperinflammation, as reflected by the secretion of cytokines, might induce thyroid dysfunction among patients with COVID-19. We explored thyroid hormone involvement in the acute phase of symptomatic COVID-19 and its possible associations with cytokine levels and mortality risk. This was a single-center study of 116 consecutive patients hospitalized for moderate-to-severe COVID-19 disease. Serum concentrations of thyroid-stimulating hormone (TSH), free thyroxine (T4), and 45 cytokines/chemokines were measured in all patients within 3 days of admission. Data were extracted retrospectively through a manual review of health records. At admission, 95 (81.9%) were euthyroid; while 21 (18.1%) had biochemically thyroid dysfunction including subclinical thyrotoxicosis (n = 11), overt thyrotoxicosis (n = 2), hypothyroidism (n = 1), non-thyroidal illness (n = 2), and normal TSH but high free T4 (n = 5). TSH levels were inversely correlated with IL-8 (rs = -0.248), IL-10 (rs = -0.253), IL-15 (rs = -0.213), IP-10 (rs = -0.334), and GM-CSF (rs = -0.254). Moreover, IL-8 levels, IP-10, and GM-CSF were significantly higher in patients with serum TSH < 0.4 mIU/L. Lastly, a two-fold increment of IL-8 and IL-10 was associated with significantly higher odds of having TSH < 0.4 mIU/L (odds ratio 1.86 (1.11-3.10) and 1.78 (1.03-3.06)). Serum TSH was not associated with 30- or 90-day mortality. In conclusion, this study suggests that fluctuations of TSH levels in patients with COVID-19 may be influenced by circulating IL-8, IL-10, IL-15, IP-10, and GM-CSF as previously described in autoimmune thyroid diseases.

Does thyroid dysfunction influence inflammatory mediators in experimental periodontitis?

Objective. The aim of the present study was to investigate the presence of inflammatory mediators in rats with only periodontitis and periodontitis in a setting of hyper- and hypo-thyroidism and to analyze the correlative linkages between inflammatory mediators and thyroid hormones. Methods. White male 12-14 weeks old inbred rats (n=48) weighing 180-200 g were employed in the experiment. They were randomly divided into the following groups: Group I - control group, Group II - group with a model of periodontitis, Group III - group with a periodontitis in a setting of hyperthyroidism, and Group IV - group with periodontitis in a setting of hypothyroidism. The presence of tumor-necrosis factor-α (TNF-α) and interleukins IL-1β and IL-10 in the periodontal homogenate supernatant was studied by a solid-phase enzyme-linked immunosorbent assay. Results. It was shown that experimental lipopolysaccharide (LPS)-induced periodontitis is accompanied by hyperproduction of pro-inflammatory cytokines (TNF-α, IL-1β) and reduction of anti-inflammatory cytokines (IL-10), whereas TNF-α underwent to maximum changes. Thyroid dysfunction exacerbates cytokine imbalance and severity of inflammation in experimental LPS-induced periodontitis, especially pronounced at hyperthyroidism, as evidenced by the predominance of TNF-α and IL-1β levels in the periodontal homogenate supernatant by 38.5% (р<0.01) and 75.6% (p<0.001), respectively, hyperthyroid over the euthyroid, and by 20.1% (p<0.05) and 24.1% (p<0.05), respectively, over the hypothyroid rats. Conclusions. Thyroid dysfunction, especially hyperthyroidism, may play an important role in the pro-inflammatory response in periodontitis. Hyperproduction of inflammatory mediators in thyroid dysfunction can induce a noticeable damage in the whole apparatus of the periodontium, thereby causing progression of periodontitis.

Associations between gut microbiota and thyroidal function status in Chinese patients with Graves' disease

OBJECTIVE

The imbalance of gut microbiota has been linked to manifold endocrine diseases, but the association with Graves' disease (GD) is still unclear. The purpose of this study was to investigate the correlation between human gut microbiota and clinical characteristics and thyroidal functional status of GD.

METHODS

14 healthy volunteers (CG) and 15 patients with primary GD (HG) were recruited as subjects. 16SrDNA high-throughput sequencing was performed on IlluminaMiSeq platform to analyze the characteristics of gut microbiota in patients with GD. Among them, the thyroid function of 13 patients basically recovered after treatment with anti-thyroid drugs (oral administration of Methimazole for 3-5 months). The fecal samples of patients after treatment (TG) were sequenced again, to further explore and investigate the potential relationship between dysbacteriosis and GD.

RESULTS

In terms of alpha diversity index, the observed OTUs, Simpson and Shannon indices of gut microbiota in patients with GD were significantly lower than those in healthy volunteers (P < 0.05).The difference of bacteria species was mainly reflected in the genus level, in which the relative abundance of Lactobacillus, Veillonella and Streptococcus increased significantly in GD. After the improvement of thyroid function, a significant reduction at the genus level were Blautia, Corynebacter, Ruminococcus and Streptococcus, while Phascolarctobacterium increased significantly (P < 0.05). According to Spearman correlation analysis, the correlation between the level of thyrotropin receptor antibody (TRAb) and the relative abundance of Lactobacillus and Ruminococcus was positive, while Synergistetes and Phascolarctobacterium showed a negative correlation with TRAb. Besides, there were highly significant negative correlation between Synergistetes and clinical variables of TRAb, TPOAb and TGAb (P < 0.05, R <  - 0.6).

CONCLUSIONS

This study revealed that functional status and TRAb level in GD were associated with composition and biological function in the gut microbiota, with Synergistetes and Phascolarctobacterium protecting the thyroid probably, while Ruminococcus and Lactobacillus may be novel biomarkers of GD.

TGF-β Physiology as a Novel Therapeutic Target Regarding Autoimmune Thyroid Diseases: Where Do We Stand and What to Expect

Transforming growth factor beta (TGF-β), as a master regulator of immune response, is deeply implicated in the complex pathophysiology and development of autoimmune thyroid diseases. Based on the close interplay between thyroid autoimmunity and TGF-β, scientific interest was shifted to the understanding of the possible role of this molecule regarding the diagnosis, prognosis, and therapy of these diseases. The main aim of this review is to present research data about possible treatment options based on the role of TGF-β in thyroid autoimmunity. Suggested TGF-β-mediated therapeutic strategies regarding autoimmune thyroid diseases include either the enhancement of its immunosuppressive role or inhibition of its facilitatory role in thyroid autoimmunity. For example, the application of hr-TGF-β can be used to bolster the inhibitory role of TGF-β regarding the development of thyroid diseases, whereas anti-TGF-β antibodies and similar molecules could impede its immune-promoting effects by blocking different levels of TGF-β biosynthesis and activation pathways. In conclusion, TGF-β could evolve to a promising, novel therapeutic tool for thyroid autoimmunity.

Cordyceps sinensis-derived fungus Isaria felina ameliorates experimental autoimmune thyroiditis in mice

AIMS

This study aimed to investigate the therapeutic effect of Cordyceps sinensis-derived fungus Isaria felina on experimental autoimmune thyroiditis (EAT).

METHODS

A NaI-induced EAT mouse model was established. The mice received oral administration of vehicle, low-dose Isaria felina (300 mg/kg), or high-dose Isaria felina (600 mg/kg) once a day for four weeks before euthanasia. Enzyme-linked immunosorbent assays (ELISA) was performed to measure serum thyroid-stimulating hormone (TSH) levels, thyroid antibodies, and cytokines. Hematoxylin and eosin (H&E) staining was conducted to assess histopathological changes in the thyroid tissue samples of mice. TUNEL and Bcl-2 immunohistochemistry (IHC) were performed to evaluate cell apoptosis, and cleaved caspase-3 IHC was performed to detect the relative expression in the thyroid tissue samples.

RESULTS

Compared with KIO₃ and KI water, NaI water consumption successfully induced EAT in mice, as evidenced by significantly increased circulating TSH and thyroid antibody levels, along with typical histopathological abnormalities of autoimmune thyroiditis (AIT) in the thyroid tissue samples. Compared with vehicle or low-dose Isaria felina, high-dose Isaria felina treatment resulted in significant reductions in white cell counts and circulating TSH, thyroid antibody, and cytokine levels of EAT mice. High-dose Isaria felina also alleviated histopathological abnormalities and attenuated TUNEL staining, Bcl-2 protein expression, and cleaved caspase-3 expression in the thyroid tissue samples.

CONCLUSION

High-dose Isaria felina treatment alleviates thyroid inflammation and cell apoptosis in EAT, serving as a novel, promising therapeutic agent for AIT.

IL-1β promotes cervical cancer through activating NF-κB/CCL-2

Cervical cancer is a malignancy with high morbidity and mortality among women. Interleukin (IL)-1β, chemokine (C-C motif) ligand 2 (CCL-2), and activation of NF-κB have been proven to be closely related to the progression of various tumors. However, their role in cervical cancer remains unclear. Cell proliferation, migration, and invasion were detected using MTT, wound healing, and transwell assays. Western blotting and qRT-PCR were used to measure expression of target genes. IL-1β greatly promoted the release of CCL-2 from HeLa cells. Activation of NF-κB and phosphorylated NF-κB (p65) nuclear translocation were accelerated by IL-1β. TPCA-1, a blocker of NF-κB, significantly inhibited the release of CCL-2 from HeLa cells. TPCA-1 markedly reversed the promotional effect of IL-1β on viability of HeLa cells. IL-1β increased the cell migration, proliferation, and invasion of HeLa cells through targeting the NF-κB/CCL-2 pathway. IL-1β/NF-κB/CCL-2 might be a promising treatment target for cervical cancer treatment and prevention.

Glycosylation of Anti-Thyroglobulin IgG1 and IgG4 Subclasses in Thyroid Diseases

OBJECTIVE

Thyroglobulin antibodies (TgAb), principally comprising immunoglobulin G (IgG), are frequently found in healthy individuals. Previously, we showed that the glycosylation levels of TgAb IgG differed across various thyroid diseases, suggesting an important role of glycosylation on antibodies in the pathogenesis of thyroid diseases. Since IgG1 and IgG4 are the primary TgAb IgG subclasses, this study aimed to investigate the glycosylation of TgAb IgG1 and IgG4 subclasses in thyroid diseases.

METHODS

TgAb IgG was purified by affinity chromatography from the serum of patients with Hashimoto's thyroiditis (HT) (n = 16), Graves' disease (GD) (n = 8), papillary thyroid carcinoma (PTC) (n = 6), and PTC with histological lymphocytic thyroiditis (PTC-T) (n = 9) as well as healthy donors (n = 10). TgAb IgG1 and IgG4 concentrations were determined by enzyme-linked immunosorbent assay, and a lectin microassay was used to assess TgAb IgG1 and IgG4 glycosylation.

RESULTS

Significantly elevated mannose, sialic acid, and galactose levels on TgAb IgG1 were found in HT and PTC patients compared to GD patients and healthy controls (all p < 0.05). The mannose, sialic acid, and core fucose levels on TgAb IgG1 in PTC-T patients were higher than in healthy controls (all p < 0.05). Additionally, TgAb IgG1 from PTC-T patients exhibited lower sialylation than that from patients with PTC and higher fucosylation than that from patients with HT (both p < 0.05). However, TgAb IgG4 glycosylation did not differ among the five groups (p < 0.05).

CONCLUSION

Our study describes different distributions of TgAb IgG1 glycosylation in various thyroid diseases. The aberrantly increased glycosylation levels of TgAb IgG1 observed in HT, PTC, and PTC-T might be indicative of immune disorders and participate in the pathogenesis of these diseases.

Crash Landing of Thyroid Storm: A Case Report and Review of the Role of Extra-Corporeal Systems

Thyroid storm is a rare but life-threatening endocrinological emergency with significant mortality ranging from 10-30% with multi-organ involvement and failure. In view of the rarity of this condition and efficacy of established first line medical treatment, use of extra-corporeal treatments are uncommon, not well-studied, and its available evidence exists only from case reports and case series. We describe a 28-year-old man who presented with an out-of-hospital cardiac arrest secondary to thyroid storm. Despite conventional first-line pharmacotherapy, he developed cardiogenic shock and circulatory collapse with intravenous esmolol infusion, as well as multi-organ failure. He required therapeutic plasma exchange, concurrent renal replacement therapy, and veno-arterial extra-corporeal membrane oxygenation, one of the few reported cases in the literature. While there was clinical stabilization and improvement in tri-iodothyronine levels on three extra-corporeal systems, he suffered irreversible hypoxic-ischemic brain injury. We reviewed the use of early therapeutic plasma exchange and extra-corporeal membrane oxygenation, as well as the development of other novel extra-corporeal modalities when conventional pharmacotherapy is unsuccessful or contraindicated. This case also highlights the complexities in the management of thyroid storm, calling for caution with beta-blockade use in thyrocardiac disease, with close monitoring and prompt organ support.

Coronavirus Disease 2019 and the Thyroid - Progress and Perspectives

SARS-CoV-2 infection (COVID-19) is currently a tremendous global health problem. COVID-19 causes considerable damage to a wide range of vital organs most prominently the respiratory system. Recently, clinical evidence for thyroidal insults during and after COVID-19 has been accumulated. As of today, almost all non-neoplastic thyroid diseases, i.e., Graves' disease, Hashimoto's thyroiditis, subacute, painless and postpartum thyroiditis, have been reported as a complication of COVID-19, and causality by the virus has been strongly implicated in all of them. Similar thyroid problems have been reported in the past with the SARS-CoV outbreak in 2002. In this review, we briefly look back at the reported evidence of alteration in thyroid functionality and thyroid diseases associated with SARS-CoV and then proceed to examine the issue with COVID-19 in detail, which is then followed by an in-depth discussion regarding a pathogenetic link between Coronavirus infection and thyroid disease.

[Autoantibodies, immunoglobulins and cytokine profile in patients with graves' disease and Graves' orbitopathy]

BACKGROUND

Graves' Orbitopathy (GO) - also known as Thyroid Eye Disease (TED) - is an autoimmune condition in the modern sense. It is closely associated with autoimmune thyroid diseases. Cytokine-mediated mechanisms play a critical part in immunopathogenesis of autoimmune thyroid diseases including GO. Investigating cytokine profiles as well as antibodies to tissue-specific antigens is essential for explaining GO pathogenesis and developing future therapeutic strategies.

AIMS

The study examines serum levels of cytokines, autoantibodies and immunoglobulins IgG and IgG4 as mediators of autoimmune inflammation in patients with GO and Graves' Disease (GD).

MATERIALS AND METHODS

The study included 52 patients (104 orbits) aged 25-70 years (mean age 48,8±12,3) in the active phase of GO and GD verified with the international diagnostic standards. These patients did not get any treatment for GO before. The control group consisted of 14 individuals (28 orbits) aged 30-68 years without known autoimmune disease.Serum levels of IgG, IgG4,TNFα, IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-17A, IL-13, sIL-6R, sTNFα- RI и TNFα- R2 IL-2R, TGFβ1, TGF β3, antibodies to TSH-receptor, free T4, free T3 and TSH were measured. A diagnostic ultrasound exam of thyroid gland, multislice computed tomography (MSCT) / magnetic resonance imaging (MRI) of orbits were performed.

RESULTS

Mean duration of GO prior to being admitted to the centre was 8,8±1,5 months (range: 1 - 48 months). According to the degree of thyrotoxicosis compensation: 24 patients were clinically euthyroid, TSH 3,3±0,7 mU/L, free T4 11,9±0,59 pmol/L, free T3 3,97±0,1 pmol/L; 28 patients were considered to have subclinical thyrotoxicosis: TSH 0,03±0,01 mU/L, free T4 14,2±1,0 pmol/L, free T3 5,77±0,49 pmol/L. Serum levels of sTNFα-R2 (p=0,041, p≤0,05), sIL-2R (p=0,020, p≤0,05), TGFβ1 (p=0,000, p≤0,001) were significantly higher in patients with GO compared to the control group. Serum levels of sTNFRα2 (p=0,038, p&lt;0,05) and TGFβ1 (P=0,011, p≤0,05) were positively correlated with the duration of GO. The positive correlations between the serum level of sIL-6R (p=0,034, p≤0,05) and the severity of GO as well as between the serum level of sTNFα- R 1 (P=0,012, p≤0,05) and activity of GO were observed. 54% of patients had elevated concentration level of IgG4 in IgG ( &gt;5%).

CONCLUSION

High levels of soluble cytokine receptors sTNFα-R2 and sIL-2R and cytokine TGFβ1 in patients with long-standing untreated GO and GD being euthyroid or having subclinical thyrotoxicosis indicate activation of regulatory T cells aimed at suppressing autoimmune processes. High concentration level of IgG4 in IgG and cytokine TGFβ1 can determine the development of fibrotic changes in the orbital tissues. A decrease in the concentration of cytokine TGFβ1 can indicate an unfavorable course of the disease GO.

Serum cystatin C is closely associated with euthyroid Hashimoto's thyroiditis in adult female Chinese patients

Objective

The aim of our study was to explore the association between serum cystatin C (CysC) and euthyroid Hashimoto’s thyroiditis.

Methods

There were 119 female euthyroid Hashimoto’s thyroiditis patients and 225 healthy controls who were recruited. Serum CysC, thyroid function, thyroid autoantibodies, fasting glucose, liver enzymes, and lipid profile were determined. Clinical parameters were compared between two groups.

Results

Serum CysC levels were significantly higher in euthyroid Hashimoto’s thyroiditis patients compared with controls. In the lowest, middle, and highest tertile groups of CysC, the percentage of Hashimoto’s thyroiditis was 15.9%, 34.2%, and 53.5%, respectively. The percentage of Hashimoto’s thyroiditis was significantly higher in the highest tertile than in the lowest and middle tertiles. Spearman’s correlation analysis showed that serum CysC levels were negatively correlated with free triiodothyronine (FT₃), and positively correlated with serum thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TGAb). Logistic regression analysis showed that serum CysC was independently related to the status of euthyroid Hashimoto’s thyroiditis.

Conclusions

The present study shows the first evidence suggesting that serum CysC levels are positively correlated with TPOAb and TGAb. Serum CysC might underlie the pathophysiologic features of euthyroid Hashimoto’s thyroiditis.

The Role of Thyroid Hormones and Autoantibodies in Metabolic Dysfunction Associated Fatty Liver Disease: TgAb May Be a Potential Protective Factor

BACKGROUND

Previous studies have shown that metabolic dysfunction associated fatty liver disease (MAFLD) is associated with thyroid hormones (THs), immunity, and inflammation status, but few studies involved thyroid autoimmunity. This study aimed to evaluate the role of THs, thyroid autoantibodies, inflammatory biomarkers in MAFLD, its cofactors, and other possible determinants.

MATERIALS AND METHODS

In the study, a total of 424 Chinese patients were selected and categorized as non-MAFLD and MAFLD. Serum thyroid hormone, thyroid autoantibody and high-sensitive C-reactive protein (hsCRP) levels were measured. The data of blood pressure, the serum lipid profile, glucose and liver enzymes were collected. The differences and association between research findings were examined and analyzed by Wilcoxon Signed Rank Test, One-Way ANOVA test and Multiple Logistic Regression models.

RESULTS

The study showed significant increase in the prevalence of MAFLD with high thyroid stimulating hormone (TSH) levels (P < 0.01) and abnormal high-sensitive C-reactive protein (hsCRP) levels (P < 0.01). The proportion of MAFLD patients decreased significantly with the rise of free thyroxine (FT4) (P = 0.04), thyrotropin receptor antibodies (TRAb) (P < 0.01), anti-thyroglobulin antibodies (TgAb) (P < 0.01), and thyroid peroxidase antibodies (TPOAb) levels (P < 0.01). Based on logistic regression analysis, MAFLD was significantly associated with lower levels of TgAb (P < 0.01), TPOAb (P < 0.01), and higher levels of hsCRP (P < 0.01) in male. In female, elevated TgAb (P < 0.01) may be a protective factor, while higher levels of hsCRP (P < 0.01) showed increased risk of MAFLD. Logistic models were adjusted for age, BMI, SBP, DBP, FBG, ALT, AST, TC, TG, LDL, HDL.

CONCLUSIONS

Taken together, TgAb may be a potential protective factor for MAFLD and elevated hsCRP level should be considered as an independent risk factor for MAFLD in both genders. TPOAb also demonstrated protective effect, but only in male. The prevalence of MAFLD increased with higher TSH levels and lower FT4, TRAb levels, but no significant association were found. However, Our findings provide a new insight into the pathogenesis of MAFLD by further investigating the impact of THs, thyroid autoimmunity, and inflammation on MAFLD patients.

The Presence of Serum TgAb Suggests Lower Risks for Glucose and Lipid Metabolic Disorders in Euthyroid General Population From a National Survey

Purpose: The expressions of antibodies against thyroid peroxidase (TPOAb) and thyroglobulin (TgAb) are very common in the sera of patients with autoimmune thyroid diseases (AITD). The relationship between thyroid autoantibodies and the occurrence of glucose and lipid metabolic disorders remains unclear. This study was performed to investigate the correlation between the presence of serum TPOAb/TgAb and those metabolic disorders in euthyroid general population. Methods: The data of this study were derived from the Thyroid Disease, Iodine status, and Diabetes National epidemiological (TIDE) survey from all 31 provinces of mainland China. A total of 17,964 euthyroid subjects including 5,802 males (4,000 with TPOAb^-TgAb^- and 1,802 with TPOAb⁺/TgAb⁺) and 12,162 females (8,000 with TPOAb^-TgAb^- and 4,162 with TPOAb⁺/TgAb⁺) were enrolled in this study. The blood glucose and lipid levels were compared between individuals with TPOAb^-TgAb^- and those with TPOAb⁺TgAb^-, TPOAb^-TgAb⁺, TPOAb⁺TgAb⁺. Results: Both fasting blood glucose (FBG) concentration and the proportion of individuals with impaired FBG (IFG) showed the decreased trends in TPOAb^-TgAb⁺ males as compared with TPOAb^-TgAb^- men. There were significantly lower FBG and higher HDL-C levels as well as tendencies toward decreased incidences of IGT and hypertriglyceridemia in TPOAb^-TgAb⁺ females when compared with TPOAb^-TgAb^- women. Binary logistic regression analysis further showed that serum TgAb single positivity in males was an independent protective factor for IFG with an OR of 0.691 (95% CI, 0.503-0.949). For females, serum TgAb single positivity was an independent protective factor for hypertriglyceridemia with an OR of 0.859 (95% CI, 0.748-0.987). Trend test showed that with the increase of serum TgAb level, there were significant decreases in the prevalence of IFG among the men with TSH ≤ 2.5 mIU/L and that of hypertriglyceridemia in the women, especially among non-obese females. Conclusion: Serum TgAb single positivity may imply a reduced risk of IFG in euthyroid men and that of hypertriglyceridemia in euthyroid women. The mechanisms for the independent protective roles of TgAb await further investigation.

Immunological aspects of autoimmune thyroid disease - Complex interplay between cells and cytokines

Autoimmune thyroid disease (ATD) is a chronic autoimmune thyroiditis with a complex pathogenesis including environmental factors, genetic background and immune system actions. Despite the large-scale research and discovery of new subpopulations of lymphocytes, cytokines, chemokines and their functions in the human body, the ethiology of ATD in many aspects remains a mystery. This article tries to summarize mostly the immunological aspects of this disease, including the roles of different cells types (dendritic cells, B cells, CD4⁺ and CD8⁺ T cells, NK cells and regulatory T cells) and of different cytokines (secreted by Th1/Th2/Th17/Th22 lymphocyte subpopulations and other, including the IL-23 and CXCL10). We describe the role of immunological abnormalities in the ATD pathogenesis and show that for some cells and cytokines their respective roles are not clear, and bi-directional action is possible. Finally, we propose a network of interactions between the immune cells and thyrocytes in the course of ATD.

A GMCSF-Neuroantigen Tolerogenic Vaccine Elicits Systemic Lymphocytosis of CD4+ CD25high FOXP3+ Regulatory T Cells in Myelin-Specific TCR Transgenic Mice Contingent Upon Low-Efficiency T Cell Antigen Receptor Recognition

Previous studies showed that single-chain fusion proteins comprised of GM-CSF and major encephalitogenic peptides of myelin, when injected subcutaneously in saline, were potent tolerogenic vaccines that suppressed experimental autoimmune encephalomyelitis (EAE) in rats and mice. These tolerogenic vaccines exhibited dominant suppressive activity in inflammatory environments even when emulsified in Complete Freund's Adjuvant (CFA). The current study provides evidence that the mechanism of tolerance was dependent upon vaccine-induced regulatory CD25⁺ T cells (Tregs), because treatment of mice with the Treg-depleting anti-CD25 mAb PC61 reversed tolerance. To assess tolerogenic mechanisms, we focused on 2D2-FIG mice, which have a transgenic T cell repertoire that recognizes myelin oligodendrocyte glycoprotein peptide MOG35-55 as a low-affinity ligand and the neurofilament medium peptide NFM13-37 as a high-affinity ligand. Notably, a single subcutaneous vaccination of GMCSF-MOG in saline elicited a major population of FOXP3⁺ Tregs that appeared within 3 days, was sustained over several weeks, expressed canonical Treg markers, and was present systemically at high frequencies in the blood, spleen, and lymph nodes. Subcutaneous and intravenous injections of GMCSF-MOG were equally effective for induction of FOXP3⁺ Tregs. Repeated booster vaccinations with GMCSF-MOG elicited FOXP3 expression in over 40% of all circulating T cells. Covalent linkage of GM-CSF with MOG35-55 was required for Treg induction whereas vaccination with GM-CSF and MOG35-55 as separate molecules lacked Treg-inductive activity. GMCSF-MOG elicited high levels of Tregs even when administered in immunogenic adjuvants such as CFA or Alum. Conversely, incorporation of GM-CSF and MOG35-55 as separate molecules in CFA did not support Treg induction. The ability of the vaccine to induce Tregs was dependent upon the efficiency of T cell antigen recognition, because vaccination of 2D2-FIG or OTII-FIG mice with the high-affinity ligands GMCSF-NFM or GMCSF-OVA (Ovalbumin323-339), respectively, did not elicit Tregs. Comparison of 2D2-FIG and 2D2-FIG-Rag1 ^-/- strains revealed that GMCSF-MOG may predominantly drive Treg expansion because the kinetics of vaccine-induced Treg emergence was a function of pre-existing Treg levels. In conclusion, these findings indicate that the antigenic domain of the GMCSF-NAg tolerogenic vaccine is critical in setting the balance between regulatory and conventional T cell responses in both quiescent and inflammatory environments.

Association between systemic lupus erythematosus and thyroid dysfunction: a meta-analysis

INTRODUCTION

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease, the pathogenesis of which remains elusive. The deficiency or excess of thyroid hormone is defined as thyroid dysfunction, including (subclinical) hypothyroidism and (subclinical) hyperthyroidism. Autoimmune factors are likely to be relevant to the development of SLE and thyroid dysfunction. Recently, many studies have indicated that the prevalence of thyroid dysfunction is higher in SLE patients than in the general population. The objective of our study was to perform a systematic review and meta-analysis to find out the relationship between SLE and thyroid dysfunction.

METHODS

Literature databases were searched, including PubMed, Embase, Web of science, Cochrane, CNKI, CHINESE WANFANG, China Science and Technology Database (VIP). Studies comparing presence of thyroid dysfunction in SLE patients to healthy controls were extracted. All the statistical analyses were performed with STATA 12.0 software.

RESULTS

Ten studies with 10,500 SLE patients and 44,170 healthy controls were included in this study. The meta-analysis results showed that the prevalence of (subclinical) hypothyroidism in SLE patients was higher than in the healthy controls (hypothyroidism: OR = 2.93, 95% CI = 1.81-4.75; subclinical hypothyroidism: OR = 5.67, 95% CI = 3.50-9.18). No statistical difference of (subclinical) hyperthyroidism was found between SLE patients and controls.

CONCLUSION

Our meta-analysis suggests that SLE is significantly associated with increased risk of (subclinical) hypothyroidism, but it has little influence on (subclinical) hyperthyroidism.

Therapeutic effect of human amniotic epithelial cells in murine models of Hashimoto's thyroiditis and Systemic lupus erythematosus

BACKGROUND AIMS

The chronic inflammation of autoimmune diseases develops repetitive localized destruction or systemic disorders, represented by Hashimoto's thyroiditis (HT) and Systemic lupus erythematosus (SLE) respectively. Currently, there are no efficient ways to treat these autoimmune diseases. Therefore, it is critically important to explore new therapeutic strategies. The aim of this study was to investigate the therapeutic efficacy of human amniotic epithelial cells (hAECs) in murine models of HT and SLE.

METHODS

Experimental autoimmune thyroiditis (EAT) was induced in female CBA/J mice by immunization with porcine thyroglobulin (pTg). hAECs were intravenously administered at different time points during the disease course. MRL-Fas^lpr mice, a strain with spontaneously occurring SLE, were intravenously administered hAECs when their sera were positive for both anti-nuclear antibodies (ANAs) and anti-double-stranded DNA (anti-dsDNA) antibodies. Two weeks after the last cell transplantation, blood and tissue samples were collected for histological examination and immune system analysis.

RESULTS

hAECs prevented lymphocytes infiltration into the thyroid and improved the damage of thyroid follicular in EAT mice. Correspondingly, hAECs administration reduced anti-thyroglobulin antibodies (TGAb), anti-thyroid peroxidase antibodies (TPOAb) and thyroid stimulating hormone (TSH) levels. SLE mice injected with hAECs appeared negative for ANAs and anti-dsDNA antibodies and showed reduced immunoglobulin profiles. Mechanically, hAECs modulated the immune cells balance in EAT and SLE mice, by downregulating the ratios of Th17/Treg cells in both EAT and SLE mice and upregulating the proportion of B10 cells in EAT mice. This was confirmed by in vitro assay, in which hAECs inhibited the activation of EAT mice-derived splenocytes. Moreover, hAECs improved the cytokine environment in both EAT and SLE mice, by suppressing the levels of IL-17A and IFN-γ and enhancing TGF-β.

CONCLUSION

These results demonstrated the immunoregulatory effect of hAECs for inflammation inhibition and injury recovery in HT and SLE murine models. The current study may provide a novel therapeutic strategy for these autoimmune diseases in clinic.

Cytokine Secretion and Pyroptosis of Thyroid Follicular Cells Mediated by Enhanced NLRP3, NLRP1, NLRC4, and AIM2 Inflammasomes Are Associated With Autoimmune Thyroiditis

Background

Inflammasomes, which mediate maturation of interleukin-1β (IL-β) and interleukin-18 (IL-18) and lead to pyroptosis, have been linked to various autoimmune disorders. This study investigated whether they are involved in the pathogenesis of autoimmune thyroiditis (AIT).

Methods

We collected thyroid tissues from 50 patients with AIT and 50 sex- and age-matched controls. Serum levels of free T3, free T4, thyrotropin, thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgAb) were measured by electrochemiluminescent immunoassays. Expression of several inflammasome components, the NOD-like receptor (NLR) family pyrin domain containing 1 (NLRP1), NLRP3, CARD-domain containing 4 (NLRC4), absent in melanoma 2 (AIM2), the apoptosis-associated speck-like protein that contains a caspase recruitment domain (ASC), caspase-1, IL-1β, and IL-18 was determined by real-time PCR and western blot. Immunohistochemistry was used to localize the expression of NLRP1, NLRP3, NLRC4, and AIM2. The Nthy-ori 3-1 thyroid cell line was stimulated with tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-17A, interleukin-6, and poly(dA:dT). The levels of IL-18 and IL-1β in the cell supernatant were measured by enzyme-linked immunosorbent assay, and lactate dehydrogenase was quantified by absorptiometry. ASC specks were examined by confocal immunofluorescence microscopic analysis. Cell death was examined by flow cytometry, and the N-terminal domain of gasdermin D was detected by western blot analysis.

Results

Expression of NLRP1, NLRP3, NLRC4, AIM2, ASC, caspase-1, pro IL-1β, pro IL-18, mRNA, and protein was significantly increased in thyroid tissues from patients with AIT, and enhanced posttranslational maturation of caspase-1, IL-18 and IL-1β was also observed. Expression of NLRP1, NLRP3, NLRC4, and AIM2 was localized mainly in thyroid follicular cells adjacent to areas of lymphatic infiltration. The thyroid mRNA level of NLRP1 and ASC was correlated to the serum TPOAb and TgAb levels in the AIT group. TNF-α and IFN-γ had a priming effect on the expression of multiple inflammasome components in thyroid cells. IFN-γ was found to strengthen poly(dA:dT)-induced cell pyroptosis and bioactive IL-18 release.

Conclusion

Our work has demonstrated for the first time that multiple inflammasomes are associated with AIT pathogenesis. The identified NLRP3, NLRP1, NLRC4, AIM2 inflammasomes and their downstream cytokines may represent potential therapeutic targets and biomarkers of AIT.

Therapeutic effects of acupuncture with MOK, a polyherbal medicine, on PTU-induced hypothyroidism in rats

Acupuncture with MOK, a polyherbal medicine (MOK pharmacopuncture), has been used for the treatment of thyroid syndromes including hypothyroidism and hyperthyroidism in traditional Korean medicine. The present study investigated the effect of MOK pharmacopuncture on hypothyroidism and the mechanism underlying its antioxidation and immune regulation effects. Hypothyroidism was induced in Sprague-Dawley rats by subcutaneous injection of Propylthiouracil (PTU; 10 mg/kg) once daily for 4 weeks. MOK was administered by acupuncture on the acupoints around the thyroid gland of PTU-induced hypothyroidism rats once daily for 2 weeks following hypothyroidism induction. Administration of MOK pharmacopuncture significantly increased the PTU-induced decrease in body temperature of hypothyroidism rats. The weights of the spleen were also significantly decreased in hyperthyroidism rats following MOK pharmacopuncture. MOK pharmacopuncture significantly decreased the thyroid stimulating hormone level and increased the T3 and T4 levels in hypothyroidism rats. Administration of MOK pharmacopuncture significantly increased the glucose levels and decreased the levels of triglycerides, total cholesterol, low-density lipoprotein-cholesterol, and alanine transaminase in the sera of hypothyroidism rats. The expression of transient receptor potential cation channel subfamily V member 1 was increased in dorsal root ganglion and brain tissues by administration of MOK pharmacopuncture, and glutathione levels and the expression of superoxide dismutase 1 and catalase were increased in the liver and brain tissues. Administration of MOK pharmacopuncture significantly inhibited interferon-γ expression and increased the expression of interleukin (IL)-4, IL-10, and Forkhead Box P3 in the spleen tissues of hypothyroidism rats. In histological analysis, the administration of MOK pharmacopuncture improved the pathological features in the thyroid glands of hypothyroidism rats. The results suggested that the administration of pharmacopuncture may ameliorate the pathological progression of hypothyroidism by multiple actions, including normalization of the hypothyroidism-induced thyroid hormone imbalance, stimulation of the antioxidant defense system, and regulation of the T helper (Th)1/Th2 imbalance. Therefore, MOK extract may be used for the treatment of hypothyroidism in Korean clinics as a useful pharmacopuncture medicine.

Association of TNF-α promoter polymorphism and Graves' disease: an updated systematic review and meta-analysis

Graves' disease (GD) is a common autoimmune disorder with a genetic predisposition. Owing to the biological effect of tumor necrosis factor-α (TNF-α) on the thyroid gland and its gene location, TNF-α should be able to influence an individual's susceptibility to GD. In the present study, we conduct a meta-analysis of rs1800629 and rs361525 in TNF-α gene from all eligible case-control studies to assess the associations amongst reported TNF-α gene with GD. A total of ten case-control studies involving 2790 GD patients and 3472 healthy controls were included. The results showed that a significant association was characterized between the rs1800629 polymorphism and GD in the homozygous model (AA compared with GG: odds ratio (OR) = 1.97, 95% confidence interval (CI) = 1.27-3.06, P=0.002) and recessive model (AA compared with GA + GG: OR = 1.62, 95% CI = 1.04-2.50, P=0.03). GD susceptibility was significantly detected in European population in all genetic models after ethnicity stratification. In sharp contrast, no significant association could be detected in Asian population. Next, we conducted a meta-analysis for another promoter SNP rs361525. However, SNP rs361525 did not show a significant association with GD in any genetic model before and after ethnicity stratification. Together, our data support that only the promoter single-nucleotide polymorphism (SNP) rs1800629 within the TNF-α gene is associated with increased risk for developing GD, especially in European population. Future large-scale studies are required to validate the associations between TNF-α gene and GD.

Association of Interleukin 10 Gene Polymorphisms with Autoimmune Thyroid Disease: Meta-Analysis

The aim of this study was to perform a meta-analysis of eligible studies and to derive a precise estimate of the association between interleukin 10 (IL10) polymorphisms and susceptibility to autoimmune thyroid disease (AITD). Meta-analyses were conducted on the associations between AITD and the -1082 G/A (rs1800896), -819 C/T (rs1800871) and -592 C/A (rs1800872) polymorphisms in IL10, and the haplotype of these polymorphisms and AITD. A total of 2903 AITD patients and 3060 controls in 10 eligible studies were included in the meta-analysis. This meta-analysis showed significant associations between IL10 at the -1082 G allele and overall AITD (OR: 1.44, 95% CI 1.13-1.82, P = 0.003), but no association between the IL10 -592 C allele and the -819 C allele and AITD. Subgroup studies demonstrated significant associations between the -1082 G allele and susceptibility to Graves' disease. Ethnicity-specific meta-analysis revealed significant associations between the -1082 G allele and AITD susceptibility in Asian populations; however, in Middle Eastern populations, no association was evident. Meta-analysis of the IL10 haplotype revealed an association between the ATA haplotype and AITD (OR: 1.17, 95% CI 1.00-1.36, P = 0.04). Meta-analysis demonstrates that the IL10 polymorphisms are associated with susceptibility to AITD.

The teleost head kidney: Integrating thyroid and immune signalling

The head kidney, analogous to the mammalian adrenal gland, is an organ unique for teleost fish. It comprises cytokine-producing lymphoid cells from the immune system and endocrine cells secreting cortisol, catecholamines, and thyroid hormones. The intimate organization of the immune system and endocrine system in one single organ makes bidirectional signalling between these possible. In this review we explore putative interactions between the thyroid and immune system in the head kidney. We give a short overview of the thyroid system, and consider the evidence for the presence of thyroid follicles in the head kidney as a normal, healthy trait in fishes. From mammalian studies we gather data on the effects of three important pro-inflammatory cytokines (TNFα, IL-1β, IL-6) on the thyroid system. A general picture that emerges is that pro-inflammatory cytokines inhibit the activity of the thyroid system at different targets. Extrapolating from these studies, we suggest that the interaction of the thyroid system by paracrine actions of cytokines in the head kidney is involved in fine-tuning the availability and redistribution of energy substrates during acclimation processes such as an immune response or stress response.

Increased Serum Levels of IL-28 and IL-29 and the Protective Effect of IL28B rs8099917 Polymorphism in Patients with Hashimoto's Thyroiditis

Hashimoto's thyroiditis (HT) is thought to result from decreased T helper type 2 (Th2) responses, leading to the progressive destruction of thyrocytes. IFN-λ1, -λ2, and -λ3 (also known as IL-29, IL-28A, and IL-28B, respectively) are recently described members of the IFN-λ family and have been shown to decrease the production of Th2 cytokines in vitro. However, the role and mechanism of IFN-λ1 in HT remain unknown. The purpose of this study was to examine whether IL29 and IL28B gene polymorphisms are susceptibility genes for the development of HT. Also, we investigated the effects of IL-29 and IL-28 serum levels in the pathogenesis of HT. Using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method, single-nucleotide polymorphisms (SNPs) of IL28B rs8099917 (IL28 G/T) and IL29 rs30461 (IL29 T/C) were studied in 99 patients with HT and 100 healthy controls. Considering the allelic distribution of the IL28 G/T polymorphism, a higher frequency of the G allele was observed in the control group versus the HT group. Thus, it was suggested that the G allele may be protective against HT pathogenesis (OR = 0.388, 95% CI = 0.217-0.693; p = 0.001). Our findings also demonstrated that there was a statistically significant difference in serum IL-28 and IL-29 levels between case and control groups (p < 0.001). Increased serum levels of IL-28 and IL-29 were found in patients with HT. However, we did not find a relationship between the IL29 gene polymorphism and HT. In conclusion, the IL28B gene polymorphism and serum IL-28 and IL-29 levels seem to play a role in the pathogenesis of HT.