8-epi-prostaglandin-f2alpha and Hypothyroidism

It has been suggested that oxidative stress plays a key role in the pathogenesis of Down syndrome (DS). However, urinary biomarkers of oxidative stress have been little studied in this condition. Thus, we aimed to assess a set of urinary oxidative/nitrosative stress biomarkers in children with DS, with and without hypothyroidism, which comprise: 8-hydroxy-2'-deoxyguanosine (8-OHdG), isoprostane 15-F(2t)-IsoP, thiobarbituric acid-reacting substances (TBARS), advanced glycation end products (AGEs), dityrosine (diTyr), hydrogen peroxide (H(2)O(2)) and nitrite/nitrate (NOx).. Fluorimetric and spectrophotometric assays were performed in children with DS (n=26), some of them taking levothyroxine for hypothyroidism (n=7), and their non-Down siblings (n=19).. We found that only levels of diTyr were increased in DS, although no differences were obtained when hypothyroid DS children were excluded. Levels of 8-OHdG, 15-F(2t)-IsoP, TBARS, AGEs, H(2)O(2) and NOx did not differ neither between DS and controls nor between hypothyroid DS children and DS without hypothyroidism diagnosed. However, diTyr is increased in hypothyroid DS children compared with controls. Negative correlations with age were obtained for 8-OHdG, diTyr and NOx in DS and controls and for 8-OHdG, 15-F(2t)-IsoP, TBARS and AGEs in DS.. Increased oxidative stress in children with DS cannot be explained by the urinary levels of 8-OHdG, 15-F(2t)-IsoP, TBARS, AGEs, diTyr, H(2)O(2) and NOx, at least with the assays used. Nonetheless, urinary diTyr could be used as oxidative/nitrosative stress biomarker in hypothyroid DS children. The present work presents evidence of a probable renal impairment in children with DS receiving levothyroxine for hypothyroidism.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adolescent; Biomarkers; Child; Child, Preschool; Deoxyguanosine; Dinoprost; Down Syndrome; Female; Glycation End Products, Advanced; Humans; Hydrogen Peroxide; Hypothyroidism; Lipid Peroxidation; Male; Nitrates; Nitrites; Oxidative Stress; Thiobarbituric Acid Reactive Substances; Tyrosine

In this study, we investigate how oxidative stress alters the urinary F2-isoprostanes' level and we examine the correlation between 8-isoPGF(2alpha) and thyroid hormones in female patients with Graves' hyperthyroidism. We quantitatively determined the concentrations of urinary F2-isoprostanes using gas chromatography-mass spectrometry in the selected ion-monitoring mode. We recruited individuals in the following three groups of subjects for this study: (1) female hyperthyroidism patients (n = 14, 21-71 years), (2) female hypothyroidism patients (n = 16, 16-66 years), and (3) female age-matched normal controls (n = 10, 20-61 years). The average concentration of 8-iso prostaglandin F(2alpha) (8-isoPGF(2alpha)) in hyperthyroidism patients was significantly higher than that in the healthy controls (P < 0.05). The concentration of 8-isoPGF(2alpha) in hypothyroidism patients was similar to that in normal controls. Although the level of 8-isoPGF(2alpha) in two of the patients was slightly elevated, the P value was not significant (NS). Our data suggest that the increased level of urinary 8-isoPGF(2alpha) may reflect possible oxidation injuries in hyperthyroidism patients due to the high level of thyroid hormones. Therefore, the elevated 8-isoPGF(2alpha) in patients could be used as an important biomarker for hyperthyroidism disease.

Topics: Adolescent; Adult; Aged; Biomarkers; Dinoprost; Female; Gas Chromatography-Mass Spectrometry; Graves Disease; Humans; Hypothyroidism; Middle Aged; Predictive Value of Tests; Thyroid Hormones