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Multigenerational selection towards longevity changes the protective role of vitamin C against graphene oxide-induced oxidative stress in house crickets
2021
Flasz, Barbara | Dziewięcka, Marta | Kędziorski, Andrzej | Tarnawska, Monika | Augustyniak, Jan | Augustyniak, Maria
This research was designed to investigate changes that can arise in an invertebrate organism due to stress caused by a strong prooxidant, graphene oxide (GO), and a potent antioxidant, vitamin C. The study aimed to investigate if vitamin C may support convalescence after chronic GO intoxication. We investigated the toxicity of chronic dietary graphene oxide administration in house cricket (Acheta domesticus) types: wild and selected for longevity (with a better developed antioxidant system, conducive to long life). Vitamin C was applied immediately after cessation of graphene oxide intoxication to check if it can support the remedial effect. The condition of cells, DNA stability, catalase activity, and the reproduction potential, measured as the Vitellogenin (Vg) protein expression level, were investigated in control and GO treated groups, recovery groups (-GO), and recovery groups with Vit. C (-GO + Vit.C). In this study vitamin C had no evident remedial effect on the house crickets exposed to graphene oxide. Most probably, the mechanism of vitamin C action, in case of intoxication with nanoparticles, is much more complicated. In the context of the results obtained, it is worth considering whether Vit. C, applied after GO intoxication, causes further disturbance of homeostasis in terms of the cells' redox potential.
Afficher plus [+] Moins [-]Preliminary Toxicity Evaluation of Aluminum/Iodine Pentoxide on Terrestrial and Aquatic Invertebrates
2017
Mulamba, Oliver | Karnjanapiboonwong, Adcharee | Kasumba, John | Anderson, ToddA. | Jackson, WAndrew | Pantoya, MichelleL.
Aluminum/iodine pentoxide (Al/I₂O₅) composites are currently receiving much attention for their capabilities as potential anthrax combatants. Their high halogen gas release, coupled with high temperature evolution from combustion, renders them effective in bacterial deactivation. Despite extensive research on the energetic capacities of these compounds, limited information is currently available in relation to their potential environmental (non-target) effects. We evaluated the effects of Al/I₂O₅ on aquatic (Daphnia magna) and terrestrial (Eisenia fetida, Acheta domesticus) invertebrates, as well as alfalfa (Medicago sativa) seed germination. Polytetrafluoroethylene (PTFE, or DuPont Teflon® MP1150) was examined concurrently to assess whether observations were general to halogen, or element specific. Our observations were based on mortality and reproduction (hatchability) for the terrestrial and aquatic assays. In all Al/I₂O₅ assays, mortality was concentration dependent, ranging from 0% mortality in the control samples to partial and complete mortality in the contaminated cases. The PTFE assays showed no mortality at all contaminant concentrations. At a maximum Al/I₂O₅ contaminant concentration of 1000 μg/g (ppm), 100% mortality was observed in cricket assay conducted in sand within 72 h exposure and earthworm assay conducted in soil within 4 days exposure. In the aquatic assay, a water concentration of 200 μg/mL (ppm) caused 100% mortality to D. magna in less than 12 h. The effect of aluminum/iodine pentoxide on earthworm cocoon hatching success was also determined. At soil concentrations ≤ 400 μg/g, hatching success for earthworm cocoons was equivalent to control (un-contaminated) soil; above this concentration, hatching success was reduced by a factor of 2. Alfalfa germination tests were performed at a single contaminant concentration of 1000 μg/g. This soil concentration was completely inhibitory to seed germination.
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