Division of Endocrinology and Metabolism, Taichung Veterans General Hospital, Taichung, Taiwan.
Metabolism. 2010 Feb;59(2):195-9. doi: 10.1016/j.metabol.2009.06.032. Epub 2009 Sep 17.
Because it is unclear whether adipose-derived hormones are related to thyroid hormone metabolism, this study evaluated the relationship between adiponectin concentrations and changes in the thyroid hormones in athyreotic patients after thyroid hormone withdrawal. Twenty-eight athyreotic thyroid cancer patients (4 male and 24 female; mean age, 52.2 +/- 11.3 years) were analyzed on the final day of levothyroxine treatment and 1 day before serum thyroglobulin and radioiodine scanning examinations after an average of 4 weeks of thyroid hormone withdrawal. Evaluations included analysis of thyroid function test, serum adiponectin, body composition by bioimpedance analysis, and insulin sensitivity index as determined by the homeostasis model assessment of insulin resistance (HOMA-IR). Discontinuation of thyroid hormone treatment resulted in a significant change in thyroid-stimulating hormone (82.1 +/- 9.8 vs 1.0 +/- 0.4 mL/L, P < .05), free thyroxine (FT4) (5.7 +/- 0.4 vs 18.7 +/- 2.3 pmol/L, P < .05), and free triiodothyronine levels (1.8 +/- 0.2 vs 3.4 +/- 0.2 pmol/L, P < .05) as compared with the prewithdrawal values, whereas circulating adiponectin levels (5.7 +/- 0.6 vs 5.4 +/- 0.6 mg/L), body fat mass (20.3 +/- 1.2 vs 19.4 +/- 1.2 kg), and insulin sensitivity index (1.8 +/- 0.2 vs 2.2 +/- 0.3) remained unaltered. A positive correlation between adiponectin and FT4 (r = 0.61, P < .01) independent of age, sex, fat body mass, HOMA-IR, and other potential covariates known to affect thyroid hormone metabolism, such as renal and liver functions, was observed after thyroid hormone withdrawal. In addition, baseline circulating adiponectin levels were correlated with a diminished postwithdrawal reduction of FT4 concentrations after adjusting for baseline FT4 levels and changes in body mass index, fat body mass, and HOMA-IR (r = 0.71, P < .01). In conclusion, adiponectin concentrations were associated with FT4 levels in the athyreotic patients after thyroid hormone withdrawal. The relevant roles of adiponectin in the regulation of thyroid hormone metabolism require further investigation.
由于脂肪衍生激素是否与甲状腺激素代谢有关尚不清楚，本研究评估了甲状腺激素撤退后甲状腺功能减退患者的脂联素浓度与甲状腺激素变化之间的关系。 分析了 28 例甲状腺癌甲状腺功能减退患者（男 4 例，女 24 例；平均年龄 52.2±11.3 岁），这些患者在甲状腺激素撤退平均 4 周后，于左旋甲状腺素治疗的最后一天和血清甲状腺球蛋白和放射性碘扫描检查前 1 天进行。评估包括甲状腺功能检查、血清脂联素、生物电阻抗分析的身体成分和胰岛素敏感性指数（稳态模型评估的胰岛素抵抗（HOMA-IR））。 甲状腺激素治疗的停止导致促甲状腺激素（82.1±9.8 与 1.0±0.4ml/L，P<0.05）、游离甲状腺素（FT4）（5.7±0.4 与 18.7±2.3pmol/L，P<0.05）和游离三碘甲状腺原氨酸水平（1.8±0.2 与 3.4±0.2pmol/L，P<0.05）发生显著变化，与撤退前的值相比，而循环脂联素水平（5.7±0.6 与 5.4±0.6mg/L）、体脂肪量（20.3±1.2 与 19.4±1.2kg）和胰岛素敏感性指数（1.8±0.2 与 2.2±0.3）保持不变。甲状腺激素撤退后，观察到脂联素与 FT4 之间呈正相关（r=0.61，P<0.01），独立于年龄、性别、体脂肪量、HOMA-IR 和其他已知影响甲状腺激素代谢的潜在混杂因素，如肾功能和肝功能。此外，调整基础 FT4 水平以及 BMI、体脂肪量和 HOMA-IR 的变化后，基础循环脂联素水平与撤退后 FT4 浓度降低相关（r=0.71，P<0.01）。总之，甲状腺激素撤退后甲状腺功能减退患者的脂联素浓度与 FT4 水平相关。脂联素在调节甲状腺激素代谢中的相关作用需要进一步研究。
