Elevated serum Meteorin-like levels in patients with hyperthyroidism

BACKGROUND: Meteorin-like (Metrnl) is a newly discovered adipomyokine that regulates systemic energy homeostasis. Both thyroid hormones and Metrnl increase energy expenditure and induce browning of adipose tissue. Thus, the aim of this study was to investigate serum Metrnl levels in hyperthyroid patients and the association of serum Metrnl levels with hyperthyroidism. METHODS: The study included 88 patients with newly diagnosed untreated overt hyperthyroidism and 100 age- and sex- matched healthy controls. Serum Metrnl levels were determined using the enzyme-linked immunosorbent assay (ELISA) method. RESULTS: Serum Metrnl levels were significantly elevated in patients with hyperthyroidism compared with controls. Linear regression analyses indicated that serum Metrnl levels were independently associated with FT3 (β = 0.324, P = 0.001), FT4 (β = 0.293, P = 0.001), and TSH (β = -0.234, P = 0.006) after full adjustment. Additionally, further logistic regression analyses revealed that the highest Metrnl tertile was significantly associated with hyperthyroidism compared with the lowest tertile (P for trend < 0.001). The relationship remained significant even after adjusting for potential confounders. Meanwhile, each one-unit increase in circulating Metrnl was independently associated with hyperthyroidism (OR 1.021, 95%CI 1.007–1.036, P < 0.01). CONCLUSION: Serum Metrnl levels were elevated in patients with hyperthyroidism and were independently associated with hyperthyroidism.