Erem Cihangir, Suleyman Akile Karacin, Civan Nadim, Mentese Ahmet, Nuhoglu İrfan, Uzun Aysegul, Coskun Hulya, Deger Orhan
a Department of Internal Medicine, Division of Endocrinology and Metabolism, Faculty of Medicine , Karadeniz Technical University , Trabzon , Turkey.
b Department of Clinical Biochemistry, Faculty of Medicine , Karadeniz Technical University , Trabzon , Turkey.
Endocr Res. 2016 Nov;41(4):350-360. doi: 10.3109/07435800.2016.1163722. Epub 2016 Apr 25.
The main objective of this study was to evaluate the levels of ischemia-modified albumin (IMA) and malondialdehyde (MDA) in patients with subclinical (SHypo) and overt hypothyroidism (OHypo), and to assess the effects of levothyroxine (LT) therapy on the oxidative stress (OS) parameters. We also investigated the relationships among serum thyroid hormones, lipid parameters, and IMA and MDA in these patients.
Thirty untreated patients with OHypo, 25 untreated patients with Shypo, and 30 age- and sex-matched healthy controls were prospectively included in the study. Biochemical and hormonal parameters including IMA and MDA were evaluated in all patients just before and one month after the maintenance of euthyroidism.
Compared with the control subjects, the levels of MDA and triglycerides (TG) significantly increased in patients with SHypo (p < 0.001 and p < 0.05, respectively), whereas high density lipoprotein cholesterol (HDL-C) levels significantly decreased (p = 0.01). Patients with OHypo showed significantly high MDA, total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), and TG levels (p = 0.001, p < 0.01, p = 0.01, and p < 0.01, respectively), and significantly low HDL-C levels compared with the controls (p < 0.05). MDA levels and lipid profile were not significantly different in the patients with OHypo when compared with the patients with SHypo. Serum IMA levels did not significantly change in patients with OHypo and SHypo compared with the controls. In the pre-treatment period, MDA levels were inversely correlated with HDL-C levels in patients with OHypo (r: -0.471, p = 0.009). Plasma MDA and LDL-C levels significantly decreased and HDL-C levels significantly increased in the groups of OHypo and SHypo after LT treatment. Serum IMA levels did not significantly change with the therapy in all patient groups.
Increased MDA levels in both patient groups represent increased lipid peroxidation which might play an important role in the pathogenesis of the atherosclerosis seen in these patients. Increased OS in patients with SHypo and OHypo could be improved by LT treatment. Also, MDA can be used as a reliable marker of OS and oxidative damage, while IMA is considered to be inappropriate.
本研究的主要目的是评估亚临床甲状腺功能减退（SHypo）和显性甲状腺功能减退（OHypo）患者的缺血修饰白蛋白（IMA）和丙二醛（MDA）水平，并评估左甲状腺素（LT）治疗对氧化应激（OS）参数的影响。我们还研究了这些患者血清甲状腺激素、血脂参数与IMA和MDA之间的关系。
前瞻性纳入30例未经治疗的OHypo患者、25例未经治疗的SHypo患者以及30例年龄和性别匹配的健康对照者。在所有患者甲状腺功能正常维持前及维持后1个月评估包括IMA和MDA在内的生化和激素参数。
与对照组相比，SHypo患者的MDA和甘油三酯（TG）水平显著升高（分别为p < 0.001和p < 0.05），而高密度脂蛋白胆固醇（HDL-C）水平显著降低（p = 0.01）。OHypo患者的MDA、总胆固醇（TC）、低密度脂蛋白胆固醇（LDL-C）和TG水平显著升高（分别为p = 0.001、p < 0.01、p = 0.01和p < 0.01），与对照组相比HDL-C水平显著降低（p < 0.05）。与SHypo患者相比，OHypo患者的MDA水平和血脂谱无显著差异。与对照组相比，OHypo和SHypo患者的血清IMA水平无显著变化。在治疗前期，OHypo患者的MDA水平与HDL-C水平呈负相关（r：-0.471，p = 0.009）。LT治疗后，OHypo和SHypo组的血浆MDA和LDL-C水平显著降低，HDL-C水平显著升高。所有患者组的血清IMA水平在治疗后无显著变化。
两组患者MDA水平升高均代表脂质过氧化增加，这可能在这些患者动脉粥样硬化的发病机制中起重要作用。LT治疗可改善SHypo和OHypo患者增加的OS。此外，MDA可作为OS和氧化损伤的可靠标志物，而IMA被认为不合适。
