Cigarette smoking and antioxidant defences in packed red blood cells prior to storage.

BACKGROUND: Red blood cells from smoking donors can have more lesions from oxidative stress, decreasing the benefits of blood transfusion. We aimed to explore the effect of cigarette smoking on the oxidative status of packed red blood cells (PRBCs) prior to storage. MATERIALS AND METHODS: We compared serum vitamin C, plasmatic malondialdehyde (MDA), and non-protein thiol groups (GSH) levels in PRBCs, as well glutathione peroxidase (GPx) and glutathione s-transferase (GST) activity in PRBCs from smoking (n=36) and non-smoking (n=36) donors. We also correlated urinary cotinine levels with these parameters. RESULTS: Cigarette smoking was associated with decreased serum levels of vitamin C and GPx, and increased GST activity in PRBCs. We found negative correlations between cotinine, GPx activity and vitamin C levels, and a positive correlation between cotinine and GST activity. DISCUSSION: Cigarette smoking changed antioxidant defences of PRBCs prior to storage and these parameters are correlated with cotinine levels. Increased RBC antioxidants such as GST may reflect an exposure to oxidants during erythropoiesis. Because of the inability of mature RBCs to resynthesise antioxidants, PRBCs from smokers may have higher risk of storage lesions than those from non-smoker donors.

Cognitive deficits and ALA-D-inhibition in children exposed to multiple metals.

Children are especially vulnerable to adverse effects of multiple metals exposure. The aim of this study was to assess some metals concentrations such as lead (Pb), arsenic (As), chromium (Cr), manganese (Mn) and iron (Fe) in whole blood, serum, hair and drinking water samples using inductively coupled plasma-mass spectrometry (ICP-MS) in rural and urban children. In addition, evaluate the adverse effects of multiple metals exposure on cognitive function and δ-aminolevulinate dehydratase (ALA-D) activity. The cognitive ability assessment was performed by the Raven's Colored Progressive Matrices (RCPM) test. The ALA-D activity and ALA-D reactivation index (ALA-RE) activity with DTT and ZnCl2 also were determined. Forty-six rural children and 23 urban children were enrolled in this study. Rural children showed percentile IQ scores in the RCPM test significantly decreased in relation to urban children. According to multiple linear regression analysis, the Mn and Fe in hair may account for the cognitive deficits of children. Manganese and Fe in hair also were positively correlated with Mn and Fe in drinking water, respectively. These results suggest that drinking water is possibly a source of metals exposure in children. ALA-D activity was decreased and ALA-RE with DTT and ZnCl2 was increased in rural children in comparison to urban children. Moreover, ALA-D inhibition was correlated with Cr blood levels and ALA-RE/DDT and ALA-RE/ZnCl2 were correlated with levels of Cr and Hg in blood. Thus, our results indicated some adverse effects of children's exposure to multiple metals, such as cognitive deficits and ALA-D inhibition, mainly associated to Mn, Fe, Cr and Hg.