title: Plasma viscosity in female patients with hypothyroidism: effects of oxidative stress and cholesterol.
abstract: Hypothyroidism is associated with atherosclerotic events, however, the mechanism is unclear. We investigated the effects of oxidative stress and cholesterol on plasma viscosity in female patients with hypothyroidism (n = 20; mean age: 45.5 +/- 5.5 years) at baseline and after L-thyroxine replacement therapy (average daily dose being 0.1 to 0.15 mg). Two blood samples were taken after 2.3 +/- 1.2 months. In hypothyroid state plasma viscosity and thiobarbituric acid reactive substance (TBARS; marker of oxidative stress were significantly higher (p < 0.001 and p < 0.001), and plasma protein thiol (antioxidants) levels were significantly lower (p < 0.001) than in the healthy state (female; n = 15). After L-thyroxine replacement therapy, patients reached to euthyroid state. In this state, the levels of plasma viscosity and TBARS were decreased (p < 0.001 and p < 0.001), and protein thiol levels were significantly elevated (p < 0.001). There was a significant correlation between plasma cholesterol and viscosity (r = 0.64, p < 0.001), as well as plasma protein thiol (r = -0.59, p < 0.001) in the patients. The correlation between viscosity and TBARS was weak (r = 0.29, p < 0.01). Therefore hypothyroidism may be associated with atherosclerotic process by different mechanisms.
authors.affiliation: Department of Biochemistry of Cerrahpasa Medical Faculty, University of Istanbul, Turkey.
authors.forename: D
authors.initials: D
authors.lastname: Konukoglu
authors.forename: M
authors.initials: M
authors.lastname: Ercan
authors.forename: H
authors.initials: H
authors.lastname: Hatemi
mesh_terms: D000328:Adult; D001798:Blood Proteins / Q000032:analysis; D001809:Blood Viscosity / Q000187:drug effects; D002784:Cholesterol / Q000097:blood / Q000502:physiology; D005260:Female; D020249:Hormone Replacement Therapy; D006801:Humans; D007037:Hypothyroidism / Q000097:blood* / Q000175:diagnosis; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology*; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D013974:Thyroxine / Q000494:pharmacology
chemical_list: D001798:Blood Proteins; D017392:Thiobarbituric Acid Reactive Substances; D002784:Cholesterol; D013974:Thyroxine