甲状腺功能减退患者甲状腺激素补充治疗前后血浆护骨素水平的变化

Changes in plasma concentrations of osteoprotegerin before and after levothyroxine replacement therapy in hypothyroid patients

目的探讨甲状腺机能减退症(甲减)患者左旋甲状腺激素(L-T4)治疗前后血浆护骨素(OPG)水平的变化。方法选择20例临床甲减、20例亚临床甲减患者和20例健康者(对照组)。所有甲减患者采用 L-T4补充治疗至甲状腺功能在正常范围内。血浆 OPG 采用酶联免疫法测定。结果 L-T4治疗前,临床甲减组和亚临床甲减组血浆 OPG 水平分别为3.13 ng/L±0.27 ng/L 和2.95ng/L±0.24 ng/L,明显高于对照组(2.42 ng/L±0.26 ng/L,P=0.000),多元相关分析结果显示,OPG与 TSH 呈正相关(r=0.306,P<0.05),与内皮依赖性血管舒张功能呈负相关(r=-0.675,P<0.01)。治疗至甲状腺功能正常后,2组血浆 OPG 水平明显降低(2.53 ng/L±0.28 ng/L,2.54 ng/L±0.21 ng/L,P=0.000),与对照组相近。治疗前后 OPG 的变化与 TSH 的变化呈正相关(P<0.05),与内皮依赖性血管舒张功能呈负相关(P<0.01)。与其他指标的变化无关。结论 OPG 可能是甲减患者血管内皮功能的重要调节分子。

Objective To investigate the alteration of plasma osteoprotegerin （OPG） concentration before and after levothyroxine （L-T4） replacement therapy and its association with endothelium-dependent arterial dilation in patients with overt hypothyroidism （oHT） and subclinical hypothyroidism （silt）. Methods L-T4 therapy was given to 20 oHT patients and 20 sliT patients, all female, till the free serum triiedothyronine （ FT3）, free thyroxin （FT4） , and thyroid-stimulating hormone （TSH） were near or within the respective normal ranges. Twenty healthy women were used as controls. Sandwich ELISA was used to measure the plasma OPG concentration before and after treatment. Results The plasma OPG levels before treatment of the oHT and sliT patients were 3. 13 ng/L ±0. 27 ng/L and 2. 95 ng/L± 0. 24 ng/L respectively, both significantly higher than that of the controls （2.42 ng/L ± 0.26 ng/L, both P = 0.000）. Multivariate analysis showed that OPG was significantly associated with TSH （ r = 0. 306, P 〈 0.05 ） and endothelium-dependent arterial dilation （ r = - 0. 675, P 〈 0.01 ） at baseline. After the normalization of thyroid function the OPG levels of the oHT and sliT patients decreased markedly to 2.53 ng/L ± 0.28 ng/L and 2.54 ng/L ± 0.21 ng/L respectively （ both P = 0.000） , very close to that in the controls. The absolute changes of OPG was significantly positively correlated with the changes of TSH （ P 〈 0.05 ）, negatively correlated with the changes of endothelium-dependent arterial dilation （ P 〈 0.01 ）, and not significantly correlated with other parameters in the hypothyroid patients during the course of treatment. Conclusion OPG mayact as an important regulatory molecule in the vasculature and, particularly, may be involved in the development of vascular dysfunction in hypothyroid patients.