Association of blood lead levels with urinary F2-8α isoprostane and 8-hydroxy-2-deoxy-guanosine concentrations in first-grade Uruguayan children

Abstract

Oxidative stress (OS) is a potential molecular mechanism for lead-induced toxicities, yet, we have limited understanding of the relation between low-level lead (Pb) exposure and OS, especially in children. This cross-sectional study examines the association between blood lead level (BLL) and two OS markers—urinary F2-8α isoprostane or isoprostane (a marker of lipid peroxidation) and 8-hydroxy-2-deoxy-Guanosine or 8-OH-dG (a marker of DNA damage) in 211 children, aged 5–8 years, from Montevideo, Uruguay. The role of dietary intakes of vitamin C and zinc in modifying the relation between BLL and OS was also examined. The mean (SD) BLL of the study children was 4.7 (2.2) μg/dL, with 30.2% children having BLL ≥5 μg/dL, the current reference level set by the US Centre for Disease Control for identifying, monitoring and management of children with elevated BLL. In covariate-adjusted analysis, there was a weak positive association between BLL and urinary isoprostane (adjusted for specific gravity) [β = 0.09, p< 0.1]. No association was found between children’s BLL and urinary 8-OH-dG. Interactions between dietary intakes of vitamin C or zinc and BLL on OS biomarkers were not consistent. However, when BLL and vitamin C or BLL and zinc were modeled together, BLL was independently associated with isoprostane concentration [β = 0.10, p< 0.05] but vitamin C or zinc intake was not. These findings suggest that there may be a potential adverse effect of BLL on OS in children with low-level Pb exposure. There is a need to study the effects of Pb on other OS measures, as well as the role of OS in mediating low-level Pb toxicity on functional outcomes.

Curative Role of D-Penicillamine versus Combined Garlic and Silymarin Extracts on Lead-Induced Nephrotoxicity and Oxidative Stress in Adult Male Albino Rats

“…Similar mechanism of toxicity has been proposed by Baranowska-Bosiacka et al (2012) for the effect of Pb-exposure on blood, Li et al (2015) for the gonadotoxic and spermiotoxic effects of lead and by Karamian et al (2015) during investigation of the neurotoxicity of lead in albino rats, all were through the generation of excessive amount of ROS and alteration of antioxidant defense systems in animals, therefore it has been suggested that Pb-induced oxidative stress contributes to the pathogenesis of lead poisoning by disrupting the pro-/antioxidant. This proposed mechanism can explain the significant alterations in the levels of erythrocyte MDA and blood GSH-Px levels which occurred in the current study and passes in agree with El-Sayed et al (2015); Roy et al (2015) In the present study, lead-exposed rats treated with D-penicillamine for 1 month showed significant drop in BLL and KLL with significant increase in ULL when compared to lead-treated rats. Also, Dpenicillamine led to decrease in MDA and increase in GSA-Px levels with great improvement in the histopathological structure of the kidney tissue.…”

Low-level arsenic exposure: Nutritional and dietary predictors in first-grade Uruguayan children

“…The study was carried out in private elementary schools in several Montevideo neighbourhoods, between November 2009 and August 2013, with recruitment methodology described elsewhere (Roy, Queirolo et al 2015). In addition to media advertising, private elementary schools in the selected neighbourhoods were contacted to gauge interest in participation, and when agreed, informational meetings were scheduled for parents.…”

Lead toxicity: a review

“…They also showed that effects of lead nitrate were more harmful in diabetic than in non-diabetic rats (Bas et al ., 2015). Oxidative stress was studied by low level lead exposure in first grade Uruguayan children, suggesting its potentially adverse effects on oxidative stress (Roy et al ., 2015 ). Impaired respiratory function was observed in workers exposed to lead with elevated blood lead concentration and zinc protoporphyrin concentration (Jurdziak et al ., 2015 ).…”