Haseki Education and Research Hospital, Nephrology, Istanbul, Turkey.
J Investig Med. 2012 Jan;60(1):23-8. doi: 10.2310/JIM.0b013e31823581dd.
In subclinical hypothyroidism (SH), serum lipid and lipoprotein concentrations are frequently changed. Compared with the healthy population, the levels of oxidized low-density lipoprotein cholesterol are higher, and the levels of high-density lipoprotein cholesterol are lower. In patients with SH, the mechanism of atherosclerosis may be attributed to the lipid abnormalities. There is evidence showing that oxidation plays an important role during the process of atherosclerosis. In this study, we evaluated the activity of paraoxonase (PON) and arylesterase (ARE) in patients with SH and investigated their relation with oxidative stress.
The study enrolled 25 patients with SH and 20 sex- and age-matched healthy controls. The patient group and the control group were compared in terms of the activity of PON and ARE and the oxidative stress index.
Between 2 groups, no significant difference was found in terms of age, sex, serum levels of total cholesterol, low-density lipoprotein, and high-density lipoprotein. In the SH group, the activity of PON was significantly lower than that observed in the control group (P < 0.05). Arylesterase activity also was significantly lower in the group with SH, compared with the control group (P < 0.05). Oxidative stress index was found to be significantly higher in the patient group, compared with the healthy subjects (P < 0.01). Oxidative stress index showed a strong positive correlation with the levels of thyroid stimulating hormone in all cases (r = 0.60, P < 0.01).
The activity of PON and ARE were significantly decreased, and oxidative stress was increased in patients with SH. Lower activities of these 2 biomarkers indicate increased oxidative damage in SH. Atherosclerosis in SH can be attributed to increased oxidative stress.
在亚临床甲状腺功能减退症（SH）中，血清脂质和脂蛋白浓度经常发生变化。与健康人群相比，氧化型低密度脂蛋白胆固醇水平较高，高密度脂蛋白胆固醇水平较低。在 SH 患者中，动脉粥样硬化的机制可能归因于脂质异常。有证据表明，氧化在动脉粥样硬化过程中起着重要作用。在这项研究中，我们评估了 SH 患者的对氧磷酶（PON）和芳基酯酶（ARE）的活性，并研究了它们与氧化应激的关系。
本研究纳入了 25 例 SH 患者和 20 名性别和年龄匹配的健康对照者。比较了患者组和对照组的 PON 和 ARE 活性以及氧化应激指数。
两组间在年龄、性别、总胆固醇、低密度脂蛋白和高密度脂蛋白血清水平方面无显著差异。在 SH 组，PON 活性明显低于对照组（P < 0.05）。SH 组的芳基酯酶活性也明显低于对照组（P < 0.05）。与健康受试者相比，患者组的氧化应激指数明显较高（P < 0.01）。氧化应激指数与所有病例中的促甲状腺激素水平呈强烈正相关（r = 0.60，P < 0.01）。
SH 患者的 PON 和 ARE 活性显著降低，氧化应激增加。这两种生物标志物活性降低表明 SH 中氧化损伤增加。SH 中的动脉粥样硬化可归因于氧化应激增加。
