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Abstract Background Iron overload has been reported in alcoholic liver cirrhosis but it remains to be established whether iron is involved in inducing oxidative damage to erythrocytes in alcoholic cirrhosis. The aim of this study was to assess oxidative damage and red cell indicators of antioxidant defences in alcoholics with mild-to-severe liver cirrhosis, taking into account the iron status. Materials and methods Twenty-nine patients with alcoholic liver cirrhosis (AC) and 27 with nonalcoholic cirrhosis (NAC) were studied. Serum lipid peroxides (LPO) were assayed by a colourimetric method. Serum-free malonyldialdehyde (MDA) was assayed by selected ion monitoring in positive chemical ionization; serum 4-hydroxy-2(E)-nonenal (4-HNE) was determined by a colorimetric method. Reduced (GSH) and oxidized glutathione (GSSG), adenine and pyridine cofactors were assayed in whole blood extracts by HPLC. Hexose-monophosphate shunt (HMPS), glycolytic pathway (EMP) and antioxidant enzyme activities were determined by standard methods. Iron status was evaluated by standard clinical chemistry and by histological grading of liver iron. Nontransferrin-bound iron (NTBI) was measured in serum by HPLC. Results GSH progressively decreased with increasing severity of liver involvement in AC and NAC. MDA, 4-HNE and NTBI were significantly higher in AC serum. Stimulation of red cell HMPS and reducing potential, in terms of NADPH production, were more pronounced in AC. Conclusions These results suggest that NTBI is more important than the decrease of antioxidant defences in inducing lipid peroxidation. NTBI may play a catalytic role in free radical reactions in the presence of cellular reductants such as NADPH. [ABSTRACT FROM AUTHOR]

Abstract Background In β-thalassaemia syndromes, decreased or impaired biosynthesis of β-globin leads to accumulation of unpaired α-globin chains. Moreover, the iron overload in β-thalassaemia patients generates oxygen-free radicals and peroxidative tissue injury. The aim of this study was to detect and correlate iron overload parameters with the oxidative stress and the antioxidant capability in β-thalassaemia patients. Design Serum iron, transferrin saturation, serum ferritin, nontransferrin-bound iron (NTBI), levels of serum free and total (free + bound) malondialdehyde (MDA) and total peroxyl radical-trapping antioxidant parameter (TRAP) were evaluated in 21 regularly transfused β-thalassaemia major (TM) patients, 13 untransfused β-thalassaemia intermedia (TI) patients and 17 healthy controls. Blood from the TM patients was drawn 48 h after the last desferoxamine (20–40 mg kg-1 ) infusion and just before transfusion. Results Free and total MDA and NTBI levels were higher in the TM patients than in the TI. In the TM patients the free MDA levels correlated positively with serum iron (r = +0·3, P = 0·0006), whereas the total MDA correlated positively with NTBI (r = +0·45, P = 0·037). However, a negative correlation was observed between TRAP and NTBI (r = -0·4, P = 0·0006). In the TI patients there was no significant correlation between free or total MDA and TRAP or NTBI. Conclusions Our results confirm the peroxidative status generated by iron overload in thalassaemia patients and highlight the rapid formation of marked amounts of free MDA despite the chelation therapy in TM patients. [ABSTRACT FROM AUTHOR]