Abstract
AIM: Lipid peroxidation and antioxidant status are becoming attractive areas of research in mood disorders. To add a new insight to the question, changes in the serum lipid peroxidation products (MDA) and activities of antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GPX), were measured in patients with bipolar disorder and unipolar depression. This study was undertaken to assess oxidative stress and antioxidant status in patients with mood disorders.
Method: The study was conducted in 71 mood disorder patients (39 bipolar disorder and 32 unipolar depression) and compared to healthy controls (n=30). Levels of plasma MDA and activities of antioxidant enzymes SOD and GPX were measured. MDA was determined as the measure of thiobarbituric acid reactive substances. GPX activity was measured by the method of Paglia and Valentine. SOD activity was determined according to the method of Sun and colleagues. These parameters were measured in 71 patients and compared to controls.
Results: Serum SOD and GPX activities was strongly decreased in bipolar and depressed patients when compared to control group (p <0.05), but there was no difference between bipolar and depressed patients. Conversly, serum MDA concentration was siginificantly increased in bipolar and depressed patients when compared to control group (p<0.05), but there was no difference between bipolar and depressed patients.
Conclusions: Decreased activities of two antioxidant defense enzymes in the present study indicate an increased oxidative stress in mood disorder. Our results suggesting that the generation of reactive oxygen species associated with the oxidative stress may induce lipid oxidation and consequently decreasing antioxidant defence in mood disorders.

Key words: Mood disorders, bipolar disorder, unipolar depression, oxidative stress, lipid peroxidation