J Toxicol Env Heal A
-
J Toxicol Env Heal A · Jan 2014
Anthocyanin-rich açaí (Euterpe oleracea Mart.) extract attenuates manganese-induced oxidative stress in rat primary astrocyte cultures.
Manganese (Mn) is an essential element for human health. However, at high concentrations Mn may be neurotoxic. Mn accumulates in astrocytes, affecting their redox status. ⋯ A larger quantity of açaí extract exacerbated the effects of Mn on these parameters except with respect to lipid peroxidation assessed by means of F₂-isoprostanes. These studies indicate that at nutritionally relevant concentration, anthocyanins obtained from açaí protect astrocytes against Mn neurotoxicity, but at high concentrations, the "pro-oxidant" effects of its constituents likely prevail. Future studies may be profitably directed at potential protective effects of açaí anthocyanins in nutraceutical formulations.
-
J Toxicol Env Heal A · Jan 2014
Comparative StudyStable nitrogen isotopes of nestling tree swallows indicate exposure to different types of oil sands reclamation.
Tree swallows (Tachycineta bicolor) inhabiting reclaimed wetlands on the oil sands in northern Alberta are potentially exposed to elevated levels of oil sands constituents such as polycyclic aromatic compounds (PAC) through diet. While increased detoxification enzyme activity as measured using 7-ethoxyresorufin O-deethylase in nestlings is a generally accepted indicator of exposure to oil sands constituents, there is no apparent method to detect dietary exposure specific to oil sands processed material (OSPM). In this study, stable C and N isotopes were analyzed from muscle and feathers of nestling tree swallows (15 d old) to distinguish dietary exposure of birds near reference and OSPM wetlands. ⋯ Our finding of limited utilization of OSPM resources by tree swallows indicates either low abundance or diversity of dietary items emerging from OSPM wetlands, or sensory avoidance of prey from those wetlands. Minimal consumption of OSPM-derived dietary sources may be attributed to published findings of limited adverse effects on tree swallow reproduction, or growth and development for these same nestlings. This study demonstrated that stable isotope analysis, particularly for N isotopes, may serve as a useful tool to trace dietary exposure to OSPM constituents as part of avian ecotoxicology assessments of reclaimed wetlands on the oil sands.
-
J Toxicol Env Heal A · Jan 2014
Genetic polymorphisms of catechol-O-methyltransferase modify the neurobehavioral effects of mercury in children.
Mercury (Hg) is neurotoxic and children may be particularly susceptible to this effect. A current major challenge is identification of children who may be uniquely susceptible to Hg toxicity because of genetic disposition. This study examined the hypothesis that genetic variants of catechol-O-methyltransferase (COMT) that are reported to alter neurobehavioral functions that are also affected by Hg in adults might modify the adverse neurobehavioral effects of Hg exposure in children. ⋯ Among girls, few interactions for Hg exposure and COMT variants were found. In contrast, among boys, numerous gene-Hg interactions were observed between individual COMT SNPs, as well as with a common COMT haplotype affecting multiple domains of neurobehavioral function. These findings suggest increased susceptibility to the adverse neurobehavioral effects of Hg among children with common genetic variants of COMT, and may have important implications for strategies aimed at protecting children from the potential health risks associated with Hg exposure.
-
J Toxicol Env Heal A · Jan 2014
Açaí (Euterpe oleracea Mart.): a tropical fruit with high levels of essential minerals-especially manganese-and its contribution as a source of natural mineral supplementation.
Açaí is a fruit from the Brazilian Amazon region, with an exotic flavor, possessing high antioxidant and anti-inflammatory properties. Based on these properties, the fruit is classified as one of the new "super fruits." The mean daily consumption of açai pulp may reach 300 ml in several Brazilian regions. Further, this fruit is also gaining popularity in Europe and North America. ⋯ Consequently, Mn intake may surpass the permitted daily maximum intake of 11 mg, which leads to a special concern, particularly for children, vegetarians, and individuals with anemia, since iron (Fe) absorption is impaired by Mn. Our findings demonstrate that this fruit is a potential source of several nutrients and a good dietary supplement to resolve malnutrition problems. However, due to the expressive levels of Mn, further studies are necessary to evaluate potential adverse effects associated with açaí consumption.