Abstract Graves' disease (GD) is an autoimmune disorder involving the thyroid gland, typically characterized by the presence of circulating autoantibodies that bind to and stimulate the thyroid ...hormone receptor (TSHR), resulting in hyperthyroidism and goiter. Organs other than the thyroid can also be affected, leading to the extrathyroidal manifestations of GD, namely Graves' ophthalmopathy, which is observed in ~ 50% of patients, and Graves' dermopathy and acropachy, which are quite rare. Presumably, the extrathyroidal manifestations of GD are due to autoimmunity against antigens common to the thyroid and other affected organs. Although its exact etiology remains to be completely understood, GD is believed to result from a complex interaction between genetic susceptibility and environmental factors. Clinically, GD is characterized by the manifestations of thyrotoxicosis as well as by its extrathyroidal features when present, the latter making the diagnosis almost unmistakable. In the absence of ophthalmopathy, the diagnosis is generally based on the association of hyperthyroidism and usually diffuse goiter confirmed with serum anti-TSHR autoantibodies (TRAbs). Hyperthyroidism is generally treated with anti-thyroid drugs, but a common long term treatment strategy in patients relapsing after a course of anti-thyroid drugs (60-70%), implies the use of radioactive iodine or surgery.
Inflammation is currently regarded as an essential component of malignancies. It is now known that the tumor microenvironment may profoundly influence the biological behavior of cancer cells and ...ultimately the patient’s outcome. Chemokine and their receptor play a major role in determining the immune phenotype of the cells infiltrating the thyroid tumor microenvironment. Experimental evidence shows that both normal and cancer thyroid cells express specific chemokine receptors. The expression of at least some of these receptors exerts several biological effects, which influence the course of the disease. The present review article will take into account the role of the most studied chemokine receptors (CXCR1, CXCR2, CXCR3, CXCR4, CXCR7, DARC, CCR3, CCR6 and CCR7) in the context of thyroid cancer. This review will focus on current knowledge provided by in vitro and in vivo studies specifically performed on thyroid cancer including (i) expression of chemokine receptors in normal and cancer thyroid cells; (ii) role of chemokine receptors in affecting the biological behavior of thyroid tumors including the metastatic process; (iii) current knowledge about immunotherapies through targeting of chemokine receptors in thyroid cancer.
Based on the role of oxidative stress in the pathogenesis of Graves' hyperthyroidism (GH) and Graves' Orbitopathy (GO), a therapy with the antioxidant agent selenium has been proposed and a number of ...studies have been performed, both
and
. In GH, reactive oxygen species (ROS) contribute to the thyroid and peripheral tissues damage. In GO, tissue hypoxia, as well as ROS, are involved in the typical changes that occur in fibroadipose orbital tissue and the perimysium of extraocular muscles. Antioxidants have been proposed to improve the effects of antithyroid drugs in GH patients, as well as the remodeling of orbital tissues in patients with GO. Here, we reviewed the literature on the possible beneficial effects and clinical use of selenium in the management of patients with GH and GO. A randomized clinical trial on the use of selenium in patients with mild GO provided evidence for a beneficial effect; no data are available on more severe forms of GO. Although the real effectiveness of selenium in patients with GH remains questionable, its use in the management of mild GO is generally believed to be beneficial, and selenium administration has been included in the clinical practice for the patients with mild eye disease.
The role of serum immunoglobulin (Ig)Ms in autoimmune thyroid diseases is uncertain.
We looked for IgMs to thyroglobulin (Tg) in patients with subacute thyroiditis (SAT), which is characterized by ...high serum Tg levels, the possible de novo appearance of IgGs to Tg (TgAb-IgGs), and no autoimmune sequelae.
TgAb-IgMs and TgAb-IgGs were detected by binding to Tg using the enzyme-linked immunosorbent assay (ELISA). The upper reference limit of TgAb-IgMs and TgAb-IgGs was established in 40 normal subjects. We looked for TgAb-IgMs in 16 patients with SAT, 11 with Hashimoto's thyroiditis (HT), and 8 with Graves' disease (GD) who were all positive for TgAb-IgGs. IgM binding to bovine serum albumin (BSA), keyhole limpet hemocyanin (KLH), and glucagon in ELISA was measured. Inhibition of TgAb-IgMs binding to coated Tg was evaluated by preincubating serum samples or IgG-depleted samples with soluble Tg.
TgAb-IgMs were positive in 10/16 patients with SAT, 2/11 with HT, and 1/8 with GD. TgAb-IgMs were higher in SAT (0.95; 0.42-1.13) (median; 25th-75th percentiles) than in HT (0.47; 0.45-0.51) and GD patients (0.35; 0.33-0.40) (P < .005 for both). IgM binding of SAT sera to BSA, KLH, and glucagon was significantly lower than Tg. Preincubation with soluble Tg reduced the binding of IgMs to coated Tg by 18.2% for serum samples and by 35.0% and 42.1% for 2 IgG-depleted samples. TgAb-IgM levels were inversely, although nonsignificantly, correlated with Tg concentrations.
Tg leak associated with thyroid injury induces the production of specific TgAb-IgMs, which, in turn, increases the clearance of Tg and might prevent the establishment of a persistent thyroid autoimmune response.
Antioxidant Therapy in Graves' Orbitopathy Lanzolla, Giulia; Marcocci, Claudio; Marinò, Michele
Frontiers in endocrinology (Lausanne),
12/2020, Letnik:
11
Journal Article
Recenzirano
Odprti dostop
The balance of the cell redox state is a key point for the maintenance of cellular homeostasis. Increased reactive oxygen species (ROS) generation leads to oxidative damage of tissues, which is ...involved in the development of several diseases, including autoimmune diseases. Graves' Orbitopathy (GO) is a disfiguring autoimmune-related condition associated with Graves' Disease (GD). Patients with active, moderate-to-severe GO, are generally treated with high doses intravenous glucocorticoids (ivGCs) and/or orbital radiotherapy. On the contrary, up to recently, local ointments were the treatment most frequently offered to patients with mild GO, because the risks related to ivGCs does not justify the relatively poor benefits expected in mild GO. However, a medical treatment for these patients is heavily wanted, considering that GO can progress into more severe forms and also patients with mild GO complain with an impairment in their quality of life. Thus, based on the role of oxidative stress in the pathogenesis of GO, a therapy with antioxidant agents has been proposed and a number of studies have been performed, both
and
, which is reviewed here.
Treatment of Graves’ orbitopathy (GO) is better performed through a multidisciplinary approach. Euthyroidism should be promptly restored. Antithyroid drug and thyroidectomy are not disease-modifying ...treatments, whereas radioiodine may be associated with worsening of GO. This risk is eliminated by glucocorticoid prophylaxis. Treatments for GO differ depending on its severity and activity. Mild forms should be treated with local measures. In addition a course of selenium may be beneficial. Glucocorticoids (oral or intravenous) represent the main treatment of moderate-to-severe GO, the intravenous route being more effective. Weekly pulses of methylprednisolone are used and the cumulative dose should not exceed 8 g. Severe adverse events have been reported, particularly with higher doses. Orbital radiotherapy can be used either alone or associated with glucocorticoids. In very severe sight-threatening GO high dose intravenous glucocorticoid should be the initial treatment, orbital decompression being considered in nonresponding patients. Rehabilitative surgery should be deferred until GO becomes inactive.
A recent clinical trial has shown a beneficial effect of the antioxidant agent selenium in Graves' orbitopathy (GO). In order to shed light on the cellular mechanisms on which selenium may act, this ...study investigated its effects in cultured orbital fibroblasts.
Primary cultures of orbital fibroblasts from six GO patients and six control subjects were established. Cells were treated with H
O
to induce oxidative stress, after pre-incubation with selenium-(methyl)selenocysteine (SeMCys). The following assays were performed: glutathione disulfide (GSSG), as a measure of oxidative stress, glutathione peroxidase (GPX) activity, cell proliferation, hyaluronic acid (HA), and pro-inflammatory cytokines.
H
O
induced an increase in cell GSSG and fibroblast proliferation, which were reduced by SeMCys. Incubation of H
O
-treated cells with SeMCys was followed by an increase in glutathione peroxidase activity, one of the antioxidant enzymes into which selenium is incorporated. At the concentrations used (5 μM), H
O
did not significantly affect HA release, but it was reduced by SeMCys. H
O
determined an increase in endogenous cytokines involved in the response to oxidative stress and GO pathogenesis, namely tumor necrosis factor alpha, interleukin 1 beta, and interferon gamma. The increases in tumor necrosis factor alpha and interferon gamma were blocked by SeMCys. While the effects of SeMCys on oxidative stress and cytokines were similar in GO and control fibroblasts, they were exclusive to GO fibroblasts in terms of inhibiting proliferation and HA secretion.
Selenium, in the form of SeMCys, abolishes some of the effects of oxidative stress in orbital fibroblasts, namely increased proliferation and secretion of pro-inflammatory cytokines. SeMCys reduces HA release in GO fibroblasts in a manner that seems at least in part independent from H
O
-induced oxidative stress. Some effects of SeMCys are specific for GO fibroblasts. These findings reveal some cellular mechanisms by which selenium may act in patients with GO.
Oxidative stress is involved in the pathogenesis of Graves hyperthyroidism (GH) and Graves orbitopathy (GO) and an antioxidant approach has been proposed for both. In GH, a disbalance of the cell ...redox state is associated with thyroid hyperfunction and antithyroid medications may reduce oxidative stress. Tissue hypoxia participates in the pathogenesis of GO, and oxygen free radicals are involved in the typical changes of orbital tissues as reported by in vitro and clinical studies. Antioxidant agents, especially selenium, have been proposed as a therapeutic option for GH and GO. A clinical study regarding the use of selenium in mild GO has provided evidence for a beneficial effect in the short term, even though its beneficial effects in the long term are still to be investigated. In addition to selenium, a protective role of other antioxidant agents, i.e., quercetin, enalapril, vitamin C, N-acetyl-L-cysteine and melatonin has been suggested by in vitro studies, although clinical studies are lacking. Here, we review the role of oxidative stress and antioxidant agents in GH and GO.
Graves orbitopathy (GO) is the most common extrathyroidal manifestation of Graves disease. Although its pathogenesis is not fully elucidated, GO is commonly considered an autoimmune disease due to ...loss of self-tolerance against autoantigens shared by thyroid epithelial cells and orbital fibroblasts. High-dose intravenous glucocorticoids (ivGCs) are the most used treatment for moderate-to-severe, active GO, but the addition of other immunomodulating treatments can improve the efficacy of ivGCs. Among the various risk factors that can affect the occurrence of GO, cholesterol may be worthy of interest. Since 2015 the role of cholesterol and cholesterol-lowering medications has been investigated. The purpose of this review is to discuss this topic, thereby offering new therapeutic opportunities for patients with GO.
We searched PubMed for studies published between January 1, 1980 and June 1, 2023, using the search terms "Graves orbitopathy," "thyroid eye disease," "Graves ophthalmopathy," "thyroid ophthalmopathy," "thyroid-associated ophthalmopathy," "endocrine ophthalmopathy," "cholesterol," "lipids," "statins," "low-density lipoprotein," "atorvastatin," and "cholesterol-lowering drugs." Only English-language articles were included.
A correlation between low-density lipoprotein cholesterol and the risk of GO development has been reported. Furthermore, low-density lipoprotein cholesterol has been proposed as a risk factor that can affect the course of GO and the response to ivGCs. The protective role of cholesterol-lowering medications in preventing GO has been also investigated. Statin treatment was found to have potential benefits in reducing the risk of GO in patients with Graves disease. Given these findings, measurement of low-density lipoprotein cholesterol and treatment of hypercholesterolemia in patients with moderate-to-severe, active GO may be considered before starting ivGCs administration. Recently, a randomized clinical trial aimed at investigating the effects of statins in GO suggested that the addition of oral atorvastatin to ivGCs improves the overall outcome of moderate-to-severe, active GO in hypercholesterolemic patients given ivGCs.
Overall, statins seem to have a preventive and therapeutic role in moderate-to-severe active GO. Their efficacy can be related to cholesterol-lowering activity, pleiotropic actions, and interaction with methylprednisolone.
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