Serum lipid oxidation and paraoxonase enzyme activity in subclinical thyrotoxicosis
Mehrdad Solati1, Ladan Atai2 & Fereidoun Azizi2
Changes in serum lipid and lipoprotein concentrations occur frequently in disorders of thyroid function. LDL-C oxidation susceptibility is higher in these patients than in normal population. This study aims at assessing lipids, lipoproteins, lipid oxidations and serum paraoxonase activity in patients with subclinical hyperthyroidism. Forty patients were compared with an age and sex matched control group. A fasting blood sample was obtained and serum total cholesterol, triglycerides, lipid oxidation parameters, and paraoxonase activity were measured. In patients with subclinical hyperthyroidism, significantly lower serum paraoxonase activity (52±26 vs 76±35 IU/ml, P<0.001), triglycerides, LDL, Total cholesterol, Total antioxidant capacity, B-carotene, Vitamin A and E were found. The results show significant changes of lipid levels in subclinical thyrotoxicosis. In addition, significant reduction in serum paraoxonase activity was observed in these patients, this can be due to the hypermethabolic state in the patients with subclinical thyrotoxicosis.