Antioxidant status and oxidative stress in hypothyroidism

Abstract

Objectives: Oxidative stress (SOX) in overt hypothyroidism (OHT) has been reported with unclear outcomes. Furthermore, the studies assessing SOX in subclinical hypothyroidism (SHT) were limited. Our present study was taken up to establish oxidative/antioxidative status in hypothyroids patients. Design and Material and Methods: One hundred and seventy-six patients with hypothyroidism diagnosed as OHT (n = 176) or SHT (n = 176) were included along with 176 healthy euthyroid controls. Serum lipid profile, malondialdehyde of plasma (MDA), protein carbonyls (PCO), glutathione reduced (GSH), superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT), and antioxidant enzyme ratio SOD-to-(GPx + CAT) were projected. Results: Compared with euthyroid controls, hypothyroid patients had dyslipidemia, notably higher MDA concentrations and PCO, significantly reduced GSH, SOD, SOD/(GPx + CAT) ratio and a noteworthy increase in GPx activity. Although CAT activity in hypothyroids was unchanged when compared to euthyroid controls. In OHT patients, the SOX was markedly more when compared to SHT patients. MDA had a positively associated with excess TSH in the OHT group. fT3 and fT4 showed positive and negative correlation, respectively, with TC, whereas TSH showed a positive correlation with low-density lipoprotein cholesterol in the OHT group. PCO was seen to have positive relations with TSH and MDA in hypothyroids. Conclusions: We found increased peroxidation of lipid, carbonylation of protein, and diminished antioxidant defense system in hypothyroids. Higher points of SOX were seen in OHT patients than SHT patients. SOX was related to change in hormone condition related to hypothyroidism.