Tryptophan Degradation and Antioxidant Status in Patients With Thyroid Disorders

The aim of this study was to evaluate the degradation of tryptophan (Trp), neopterin production and antioxidant capacity in patients with benign and malignant thyroid disease. For this reason, the levels of tryptophan, kynurenine (Kyn) and neopterin, and superoxide dismutase (SOD) and catalase (CAT) enzyme activities in 67 thyroid patients were evaluated in our study and the results were compared with 30 healthy controls. Tryptophan and kynurenine levels in thyroid patients decreased compared to the control group. Patients with thyroid disease had lower CAT activity than the control group. The neopterin and tryptophan levels in malignant and benign patients were also significantly different. The results of the present study suggest that thyroid disorders may lead to changes in tryptophan degradation, neopterin production and CAT enzyme activities