Blood antioxidant status and urinary levels of catecholamine metabolites in beta-thalassemia

It has been reported that iron overload in B-thalassemia leads to an enhanc ed generation of reactive oxygen species and to oxidative stress. We have s tudied the oxidant/antioxidant imbalance in the blood of 48 transfusion-dep endent beta-thalassemic patients (TLP) (17 males, 31 females, 11-22 year), under chelation therapy, and in 40 sex and age matched healthy controls (CT R). Plasma and lymphocyte levels of vitamin E (Vit E), ubiquinol (CoQ(10)H( 2)), ubiquinone (CoQ(10)), plasma concentrations of vitamin A (Vit A), beta -carotene, lycopene, vitamin C (Vit C), total thiols, fatty acid patterns o f phospholipids (PL-FA), and plasma and urinary markers of lipoperoxidation (TBA-RM, conjugated dienes, and azelaic acid (AZA), as well as the urinary levels of catecholamine and serotonin metabolites, were evaluated by gas c hromatography-mass spectrometry (GC-MS), HPLC and spectrophotometry. Routin e laboratory blood analyses were performed on the same samples; 39/48 TLP w ere HCV positive. Blood samples were collected just before transfusion, the 24 h urine samples the day before. Our results clearly showed that a sever e oxidative stress occurs in the plasma of TLP in comparison with CTR. In f act, the levels of lipophilic antioxidants and ascorbate were severely depl eted: CoQ(10)H(2) (-62.5%), total CoQ(10) (-35.1%), Vit E (-43.8%), beta-ca rotene (-31.1%), lycopene (-63.7%), Vit A (-35.9%), Vit C (-23.1%). The imp airment of the antioxidant status was associated with elevated plasma level s of by-products of lipoperoxidation and urinary concentrations of catechol amine metabolites and of AZA, indicating a high degree of both neurological stress and lipoperoxidation. A significant positive correlation was found between vitamin E and non-transferrin-bound iron (NTBI) (r = -0.81; p < 0.0 01), while no correlation was found between antioxidant depletion and ferri tin serum levels, average blood consumption, or the presence of clinical co mplications. The administration of selective antioxidants along with an app ropriate diet might represent a promising way of counteracting oxidative da mage and its deleterious effects on the progression of the disease.