Baskol G, Atmaca H, Tanriverdi F, Baskol M, Kocer D, Bayram F
Department of Biochemistry and Clinical Biochemistry, Erciyes University Faculty of Medicine, Kayseri, Turkey.
Exp Clin Endocrinol Diabetes. 2007 Sep;115(8):522-6. doi: 10.1055/s-2007-981457.
The present study was designed to investigate the relationship between the serum levels of oxidant-antioxidant system (malondialdehyde (MDA) level, Paraoxonase (PON1) activity, nitric oxide (NO) level and superoxide dismutase (SOD) activity) and thyroid hormone status in hypothyroidism pre and posttreatment. The study group comprised 33 patients with primary hypothyroidism. 18 of these patients were reevaluated after euthyroid state i.e. at least 6 months of thyroxine replacement. The patients were compared with 26 normal healthy controls. Serum MDA level, PON1 activity, NO level and SOD activity were measured according to an enzymatic spectrophotometric method. MDA levels were found higher in patients with hypothyroidism before the treatment than the controls. MDA levels were also found to be decreased after the treatment in patients with hypothyroidism. However MDA were found still higher than the controls after the treatment. PON1 activity was found to be lower in patients pretreatment when compared to posttreatment hypothyroidism and controls. Posttreatment of hypothyroidism mean PON1 activity significantly increased compared to pretreatment level but it was still significantly lower than control level. NO level was higher in pretreatment hypothyroidism when compared to controls. SOD activity was not found different in patients before treatment when compared to controls. SOD activity was significantly higher in after treatment when compared to both pretreatment and control levels. In conclusion, increased ROS levels in hypothyroidism may result in a pro-oxidation environment, which in turn could result in decreased antioxidant PON1 activity, increased MDA and NO levels. As a result, lipid peroxidation may have a role in the pathogenesis of the atherosclerosis in hypothyroidism.
本研究旨在探讨甲状腺功能减退症患者治疗前后血清氧化-抗氧化系统水平（丙二醛（MDA）水平、对氧磷酶（PON1）活性、一氧化氮（NO）水平和超氧化物歧化酶（SOD）活性）与甲状腺激素状态之间的关系。研究组包括33例原发性甲状腺功能减退症患者。其中18例患者在甲状腺功能正常状态（即至少6个月的甲状腺素替代治疗后）进行了重新评估。将这些患者与26名正常健康对照者进行比较。采用酶分光光度法测定血清MDA水平、PON1活性、NO水平和SOD活性。发现甲状腺功能减退症患者治疗前的MDA水平高于对照组。甲状腺功能减退症患者治疗后的MDA水平也有所下降。然而，治疗后MDA水平仍高于对照组。与治疗后甲状腺功能减退症患者及对照组相比，治疗前患者的PON1活性较低。甲状腺功能减退症患者治疗后的平均PON1活性较治疗前水平显著升高，但仍显著低于对照水平。与对照组相比，甲状腺功能减退症患者治疗前的NO水平较高。与对照组相比，治疗前患者的SOD活性无差异。与治疗前及对照水平相比，治疗后患者的SOD活性显著升高。总之，甲状腺功能减退症患者体内活性氧水平升高可能导致促氧化环境，进而导致抗氧化剂PON1活性降低、MDA和NO水平升高。因此，脂质过氧化可能在甲状腺功能减退症患者动脉粥样硬化的发病机制中起作用。
