Serum levels of leptin and adiponectin in patients with autoimmune Hashimoto's thyroiditis

Abstract

Introduction: 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.Aim: 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.Materials and methods: 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).Results: 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<0.001), triglycerides (r=0.223, p=0.033), and immunoreactive insulin (r=0.488, p<0.001) levels. Serum adiponectin concentrations were higher in euthyroid HT patients than in the other groups, but the difference was not statistically significant (p=0.68). We found a positive correlation between adiponectin and HDL cholesterol levels (r=0.442, p<0.001), and negative with body mass index (r=−0.217, p=0.03), and immunoreactive insulin (r=−0.341, p=0.002).Conclusions: The results of this study suggest that leptin has a stronger effect than adiponectin in Hashimoto’s thyroiditis, which can be used to develop new therapeutic agents that modify its effect in the organism.

Keywords

• adipocytokines
• Hashimoto’s thyroiditis