leptin and Hashimoto-Disease

Adipose tissue is immunologically and hormonally active, and these effects are mediated largely by adipocytokines. Thyroid hormones regulate metabolism and organ function, and Hashimoto's thyroiditis (HT) is the most common autoimmune disease affecting thyroid function.. To evaluate the levels of the adipocytokines leptin and adiponectin in patients with autoimmune HT, and to perform a comparative intragroup analysis in patients with different stages of gland functional activity, and in a control group.. Ninety-five patients with HT and 21 healthy controls were enrolled in the study. Venous blood was taken without anticoagulants after at least 12 hours of fasting, and serum samples were frozen at -70°C until analysis. Serum levels of leptin and adiponectin were determined by an enzyme-linked immunosorbent assay (ELISA).. Serum levels of leptin in HT patients were higher than those in the control group (4.5±5.2 ng/mL vs. 1.9±1.3 ng/mL). The hypothyroid patient's group showed significantly higher levels of leptin than those of the healthy controls (5.1±5.2 ng/mL vs. 1.9±1.3 ng/mL), (p=0.031). Leptin levels correlated positively with body mass index (r=0.533, p.

Topics: Adipokines; Adiponectin; Hashimoto Disease; Humans; Hypothyroidism; Leptin

The study was designed to evaluate the effect of thyroid function on serum levels of different adipokines in obesity. We investigated relationships between the thyroid axis and serum levels of leptin, adiponectin, and chemerin, and we assessed the influence of autoimmune thyroiditis (AIT) on those relations.. The participants of this study included 181 euthyroid patients (147 women and 34 men) with obesity [body mass index (BMI) 30-39.9 kg/m²] and severe (morbid) obesity (BMI ≥ 40 kg/m²), aged 18 to 65 years. We divided all obese patients by thyrotropic hormone (TSH) tertiles, and we compared all participants according to BMI. Patients were further divided into the following subgroups: with chronic autoimmune thyroiditis and without autoimmune thyroiditis.. Comparison of obese patients according to TSH tertile showed significantly higher serum concentrations of leptin, chemerin, and thyroid antibodies and an increased leptin/adiponectin ratio in the group with high normal TSH. We observed statistically significant correlations between serum TSH and BMI, leptin, chemerin, thyroid peroxidase antibodies, and the leptin/adiponectin ratio. In patients diagnosed with autoimmune thyroiditis, higher levels of antibodies and TSH were found, but there were no differences in homeostatic model assessment index (HOMA-I), the leptin/adiponectin ratio, and adipokine levels. In obese patients the relationships between serum leptin, chemerin, the leptin/adiponectin ratio, and BMI were dependent on each other.. Serum leptin, chemerin, the leptin/adiponectin ratio, and BMI are significantly higher in patients with high normal TSH; however, selected adipokines are not related to the presence of autoimmune thyroiditis. There are interplays between TSH, adipokines, and obesity, but how these relationships are related remains unknown.

Topics: Adipokines; Adiponectin; Adolescent; Adult; Aged; Body Mass Index; Female; Hashimoto Disease; Humans; Leptin; Male; Middle Aged; Obesity; Thyroiditis, Autoimmune; Thyrotropin; Young Adult

Leptin has been found to be involved in the development and progression of many autoimmune diseases. As an organ-specific autoimmune disease, the pathogenesis of Hashimoto's thyroiditis has not been fully elucidated. It has been reported that serum leptin level is increased in Hashimoto's thyroiditis, but other studies have not shown any difference. We replicated a mouse model of experimental autoimmune thyroiditis (EAT) with a high-iodine diet and found that injection of the leptin receptor antagonist Allo-aca reduced thyroid follicle destruction and inflammatory cell infiltration in EAT mice, and thyroxine and thyroid autoimmune antibody levels. Further investigation revealed that Allo-aca promotes the differentiation of Treg cells and inhibits the differentiation of Th17 cells. We believe that Allo-aca can alter the differentiation of Treg/Th17 cells by inhibiting the leptin signaling pathway, thereby alleviating thyroid injury in EAT mice. Interfering with the leptin signaling pathway may be a novel new approach to treat treating and ameliorating Hashimoto's thyroiditis.

Topics: Animals; Autoimmune Diseases; Cell Differentiation; Hashimoto Disease; Leptin; Mice; Receptors, Leptin; T-Lymphocytes, Regulatory; Th17 Cells; Thyroiditis, Autoimmune

Autoimmune thyroid diseases (AITDs), predominately Graves׳ disease and Hashimoto׳s thyroiditis, comprise the most common autoimmune diseases in humans. Both have the production of anti-thyroid antibody as an important aspect and both are much more prevalent in females, being at least 10 times more common than in males. Using these two clues, a hypothesis for the initiation of thyroid autoimmunity is proposed that helps to make the case that the thyroid is one of the most sensitive sites for autoimmunity and helps account for the prevalence and the observed sex differences in AITDs and associated diseases, such as type 1 diabetes and Latent Autoimmune Diabetes in Adults (LADA). The primary mechanisms proposed involve the underlying state of inflammation as a result of the adipokines, especially leptin, TNF-α, and IL-6, and the receptors able to recognize pathogen-associated molecular patterns (PAMP׳s) and damage-associated molecular patterns (DAMP׳s) through Toll-like receptors (TLR) and others receptors present on thyrocytes. The adipokines are produced by adipose tissue, but have hormone-like and immune modulating properties. As the levels of leptin are significantly higher in females, an explanation for the sex difference in thyroid autoimmunity emerges. The ability of the thyrocytes to participate in innate immunity through the TLR provides an adjuvant-like signal and allows for the action of other agents, such as environmental factors, viruses, bacteria, and even stress to provide the initiation step to break tolerance to thyroid self-antigens. Seeing the thyroid as one of the most sensitive sites for autoimmunity, means that for many autoimmune disorders, if autoimmunity is present, it is likely to also be present in the thyroid - and that that condition in the thyroid was probably earlier. The evidence is seen in multiple autoimmune syndrome.

Topics: Adipokines; Animals; Autoantibodies; Autoantigens; Autoimmunity; Diabetes Mellitus, Type 1; Female; Graves Disease; Hashimoto Disease; Humans; Immunity, Innate; Inflammation; Leptin; Male; Mice; Prevalence; Receptors, Pattern Recognition; Sex Factors; Thyroid Gland

Leptin modulates T cell function and plays an important role in autoimmune diseases. Our study aimed to explore the role of leptin and T helper type 17 (Th17) cells in Hashimoto's thyroiditis patients. Twenty-seven patients with Hashimoto's thyroiditis (HT) and 20 healthy controls were enrolled into the current study. A modest increase of plasma leptin in HT patients and the CD4(+) T cell-derived leptin from HT patients was stronger than that from healthy controls. In HT patients, there are no statistically significant correlations between plasma leptin concentrations and the percentage of Th17 cells or the level of retinoic acid-related orphan receptor γt (RORγt), but strong positive correlations were observed between CD4(+) T cell-derived leptin and the percentage of Th17 cells or the level of RORγt mRNA, and additionally significantly up-regulated leptin, interleukin (IL)17 and RORγt mRNA levels in the thyroid tissue. Furthermore, neutralization of leptin decreases the frequency of Th17 cells in vitro. Current study has revealed an increased leptin involvment in Hashimoto's thyroiditis associated with an increased number of Th17 cells.

Topics: Adult; Autoantibodies; CD4-Positive T-Lymphocytes; Female; Hashimoto Disease; Humans; Interleukin-17; Leptin; Leukocytes, Mononuclear; Middle Aged; Nuclear Receptor Subfamily 1, Group F, Member 3; Th17 Cells; Thyroxine; Triiodothyronine

Leptin, adiponectin and resistin, mainly produced by adipocytes, play a major role in body weight regulation. Disturbances in the maintenance of normal body weight are found to occur also in thyroid diseases. There is a close relationship of the changes in thyroid hormones with the contents of adipose tissue and adipocyte-secreted proteins regulating energetic metabolism in the body. The study objective was to analyze the levels of leptin, adiponectin and resistin in children with untreated Graves' disease, subclinical hypothyroidism in Hashimoto's thyroiditis and in children with simple goiter. The study involved 78 patients with Graves' disease (29 girls and 2 boys, aged 6-21 years, mean 15.2) and with Hashimoto's thyroiditis (30 girls and 2 boys, aged 9-18 years, mean 14.5). The control group consisted of adolescents with simple goiter (13 girls and 2 boys, aged 9-18 years, mean 14.8). The levels of leptin, adiponectin and resistin were determined using the ELISA method (R&D System, USA). Patients with untreated Graves' disease showed higher adiponectin level than the patients with hypothyroidism in Hashimoto's thyroiditis and in simple goiter (14.24 +/- 0.89 vs. 9.18 +/- 2.65, 10.15 +/- 2.5, p < 0.007, p < 0.01), but lower resistin level as compared to simple goiter and Hashimoto's thyroiditis (10.24 +/- 5.2 vs. 13.29 +/- 3.8, 12.2 +/- 2.8, p < 0.01, NS). The analysis of leptin levels revealed no significant differences between children with subclinical hypothyroidism and untreated Graves' disease (4.42 +/- 0.87 vs. 3.1 +/- 0.45 NS). In conclusion, we suggest that disturbances in thyroid hormones in thyroid diseases have an essential effect on the levels of adiponectin and resistin released by adipose tissue.

Topics: Adiponectin; Adipose Tissue; Adolescent; Body Weight; Child; Enzyme-Linked Immunosorbent Assay; Female; Goiter; Graves Disease; Hashimoto Disease; Humans; Leptin; Male; Resistin; Statistics, Nonparametric; Thyroid Hormones; Young Adult