Evidence that Electromagnetic Radiation is Genotoxic: The ...
Genotoxic effects of ZnO nanoparticles in male wistar rats
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S194 Abstracts / Toxicology Letters 229S (2014) S40–S252 It is widely accepted that silver ion release is an important mechanism for biocidal effects of silver nanoparticles (AgNPs). Nev- ertheless, it has been shown that the direct interactions of AgNPs with microbial cells may result in their enhanced toxicity. The aim of the current study was to evaluate how different physical-chemical properties of Ag NPs as size and charge influence their binding, internalization and toxicity to yeast Saccharomyces cerevisiae. Four different AgNPs were studied: 10 and 80 nm AgNPs, both citrates (negatively charged) and branch-PEI-coated (posi- tively charged). AgNO 3 was used as an ionic control. The stability and solubility of the AgNPs was studied by the dynamic light scat- tering (Malvern Zetasizer) and by metal-specific Ag-sensor bacteria and atomic absorption spectroscopy (AAS), respectively. Yeast cells were exposed to AgNPs in deionized water for 24 h at 30 ◦ C. Cell viability was assessed by the colony-forming ability and by staining with fluorescein diacetate and Alamar Blue. Particle- cell interactions were assessed by confocal, scanning (SEM) and transmission electron microscopy (TEM). Toxicity studies showed that 10-nm AgNPs were ∼10-times more toxic than 80-nm AgNPs and positively charged (bPEI- coated) AgNPs were ∼10-times more toxic than negatively charged (citrate-coated) AgNPs. SEM and TEM visualization showed that positively charged but not negatively charged AgNPs adsorbed onto the yeast’s surface. Thus, variation of the size, coating and charge of NPs may be used for the design of new more efficient antifungal nanomaterials. This work is supported by the grant 3.2.0801.11-0026, IUT 23-5, ETF9001 and COST ES1205. http://dx.doi.org/10.1016/j.toxlet.2014.06.657 P-3.145 Genotoxic effects of ZnO nanoparticles in male wistar rats Vilena Kasuba 1,∗ , Davor Zeljezic 1 , Marin Mladinic 1 , Ruzica Rozgaj 1 , Mirta Milic 1 , Nevenka Kopjar 1 , Vedran Micek 2 1 Institute for Medical Research and Occupational Health, Mutagenesis Unit, Zagreb, Croatia, 2 Institute for Medical Research And Occupational Health, Animal Breeding Unit, Zagreb, Croatia Zinc oxide nanoparticles (ZnO NPs) find applications in indus- try and medicine. The use of nanomaterials has led to the growing concern about their toxicity. Present in vivo study in 10 weeks old male Wistar rats was aimed at investigating the oral toxicty of nano sized ZnO (<35 nm). The genotoxic potential was deter- mined using the alkaline comet assay on kidney, liver and brain cells, and blood lymphocytes. The permanent DNA damage was assessed using the in vivo MN asay in blood. Rats were adminis- tered with ZnONPs water dispersion at 5, 10 and 50 mg kg −1 bw −1 daily, or water only for 28 consecutive days through oral gavage. Ethyl methanesulphonate (EMS) as a positive control was given in three daily doses of 300 mg kg −1 bw −1 begining at 25 day. For statistical analysis ANOVA and Kruskal–Wallis test were applied. Kidney and brain showed significantly higher values of Tail Inten- sity (TI) at concentrations of 5 and 50 mg kg −1 bw −1 as compared to control. Blood sample significantly differed in TI at a concentra- tion of 50 mg kg −1 compared to all other concentrations including control. All applied concentrations of ZnO NPs in liver significantly increased TI compared to control. MN in vivo test in both eryth- rocytes and reticulocytes showed significant differences between the highest ZnO NPs concentration and all other applied concen- trations. Further in vivo studies with the implementation of new biomarkers should validate these results. http://dx.doi.org/10.1016/j.toxlet.2014.06.658 P-3.146 Comparison of two different application routes of nanosilver in rats – A toxicokinetic study Sabine Horzowski 1 , Dajana Lichtenstein 1 , Jana Potkura 1 , Axel Oberemm 1 , Otto Creutzenberg 2 , Alfonso Lampen 1,∗ 1 Federal Institute for Risk Assessment, Berlin, Germany, 2 Fraunhofer ITEM, Hannover, Germany Owing to their antimicrobial properties, silver nanoparticles are the most commonly used nanoparticles. The constantly increas- ing use of silver nanoparticles in products related to food and food contact materials is the reason why oral administration of nanopar- ticles is considered as an important uptake route and should be studied. Therefore, the tissue distribution and excretion of coated silver nanoparticles was investigated in rats after single oral adminis- tration including a 7-days post treatment observation time. The animals received silver nanoparticles at a dose of 20 mg/kg body weight and an equimolar dose of silver ions by gavage. The silver content was measured in different organs after days 1, 2, 3 and 7. To assess the effect of the intestinal passage on systemic bioavailability an additional group of rats was intravenously administered with 4 mg/kg body weight silver nanoparticles and a group was treated with an equimolar dose of silver ions. The accumulation of silver was compared after 24 h single intravenous administration. So far, the accumulation of silver was observed in different organs. As expected, most of the nanosilver was excreted via feces and minor amounts were detected in intestine and colon. Orally administered ionic silver was detected in feces and additionally in the urine. Remarkably, also after intravenous injection of nanosil- ver silver was found in feces, which suggests biliary excretion of silver nanoparticles. It is concluded that the oral resorption of nanosilver results in an accumulation of silver in different organs and feces and the intravenous application suggests a biliary excretion. http://dx.doi.org/10.1016/j.toxlet.2014.06.659 P-3.147 The role of coating materials and zeta potential in iron oxide nanoparticle translocation in human intestinal cells Dajana Lichtenstein 1 , Annabelle Bertin 2 , Doreen Fiedler 1 , Sabine Horzowski 1 , Richard Palavinskas 1 , Birgit Niemann 1 , Andreas Thünemann 2 , Alfonso Lampen 1,∗ 1 Federal Institute for Risk Assessment, Berlin, Germany, 2 Federal Institute for Materials Research and Testing, Berlin, Germany Due to the more popular use of engineered nanoparticles (ENPs) for food-associated products e.g. in dietary supplements, consumer exposure rises increasingly. Therefore further knowledge about uptake of ENPs after oral exposure is of imperative need. Here, the uptake and transport across the intestinal barrier are the most important aspects and especially the coating of ENPs plays a crucial role.
Transcript of Genotoxic effects of ZnO nanoparticles in male wistar rats
S194 Abstracts / Toxicology Letters 229S (2014) S40–S252
It is widely accepted that silver ion release is an importantmechanism for biocidal effects of silver nanoparticles (AgNPs). Nev-ertheless, it has been shown that the direct interactions of AgNPswith microbial cells may result in their enhanced toxicity.
The aim of the current study was to evaluate how differentphysical-chemical properties of Ag NPs as size and charge influencetheir binding, internalization and toxicity to yeast Saccharomycescerevisiae. Four different AgNPs were studied: 10 and 80 nm AgNPs,both citrates (negatively charged) and branch-PEI-coated (posi-tively charged). AgNO3 was used as an ionic control. The stabilityand solubility of the AgNPs was studied by the dynamic light scat-tering (Malvern Zetasizer) and by metal-specific Ag-sensor bacteriaand atomic absorption spectroscopy (AAS), respectively.
Yeast cells were exposed to AgNPs in deionized water for 24 h at30 ◦C. Cell viability was assessed by the colony-forming ability andby staining with fluorescein diacetate and Alamar Blue. Particle-cell interactions were assessed by confocal, scanning (SEM) andtransmission electron microscopy (TEM).
Toxicity studies showed that 10-nm AgNPs were ∼10-timesmore toxic than 80-nm AgNPs and positively charged (bPEI-coated) AgNPs were ∼10-times more toxic than negativelycharged (citrate-coated) AgNPs. SEM and TEM visualizationshowed that positively charged but not negatively charged AgNPsadsorbed onto the yeast’s surface. Thus, variation of the size,coating and charge of NPs may be used for the design of new moreefficient antifungal nanomaterials.
This work is supported by the grant 3.2.0801.11-0026, IUT 23-5,ETF9001 and COST ES1205.
http://dx.doi.org/10.1016/j.toxlet.2014.06.657
P-3.145Genotoxic effects of ZnO nanoparticles in malewistar rats
Vilena Kasuba 1,∗, Davor Zeljezic 1, Marin Mladinic 1, RuzicaRozgaj 1, Mirta Milic 1, Nevenka Kopjar 1, Vedran Micek 2
1 Institute for Medical Research and Occupational Health,Mutagenesis Unit, Zagreb, Croatia, 2 Institute for Medical ResearchAnd Occupational Health, Animal Breeding Unit, Zagreb, Croatia
Zinc oxide nanoparticles (ZnO NPs) find applications in indus-try and medicine. The use of nanomaterials has led to the growingconcern about their toxicity. Present in vivo study in 10 weeksold male Wistar rats was aimed at investigating the oral toxictyof nano sized ZnO (<35 nm). The genotoxic potential was deter-mined using the alkaline comet assay on kidney, liver and braincells, and blood lymphocytes. The permanent DNA damage wasassessed using the in vivo MN asay in blood. Rats were adminis-tered with ZnONPs water dispersion at 5, 10 and 50 mg kg−1 bw−1
daily, or water only for 28 consecutive days through oral gavage.Ethyl methanesulphonate (EMS) as a positive control was givenin three daily doses of 300 mg kg−1 bw−1 begining at 25 day. Forstatistical analysis ANOVA and Kruskal–Wallis test were applied.Kidney and brain showed significantly higher values of Tail Inten-sity (TI) at concentrations of 5 and 50 mg kg−1 bw−1 as comparedto control. Blood sample significantly differed in TI at a concentra-tion of 50 mg kg−1 compared to all other concentrations includingcontrol. All applied concentrations of ZnO NPs in liver significantlyincreased TI compared to control. MN in vivo test in both eryth-rocytes and reticulocytes showed significant differences betweenthe highest ZnO NPs concentration and all other applied concen-
trations. Further in vivo studies with the implementation of newbiomarkers should validate these results.
http://dx.doi.org/10.1016/j.toxlet.2014.06.658
P-3.146Comparison of two different application routesof nanosilver in rats – A toxicokinetic study
Sabine Horzowski 1, Dajana Lichtenstein 1, Jana Potkura 1, AxelOberemm 1, Otto Creutzenberg 2, Alfonso Lampen 1,∗
1 Federal Institute for Risk Assessment, Berlin, Germany, 2 FraunhoferITEM, Hannover, Germany
Owing to their antimicrobial properties, silver nanoparticles arethe most commonly used nanoparticles. The constantly increas-ing use of silver nanoparticles in products related to food and foodcontact materials is the reason why oral administration of nanopar-ticles is considered as an important uptake route and should bestudied.
Therefore, the tissue distribution and excretion of coated silvernanoparticles was investigated in rats after single oral adminis-tration including a 7-days post treatment observation time. Theanimals received silver nanoparticles at a dose of 20 mg/kg bodyweight and an equimolar dose of silver ions by gavage. The silvercontent was measured in different organs after days 1, 2, 3 and 7.
To assess the effect of the intestinal passage on systemicbioavailability an additional group of rats was intravenouslyadministered with 4 mg/kg body weight silver nanoparticles anda group was treated with an equimolar dose of silver ions. Theaccumulation of silver was compared after 24 h single intravenousadministration.
So far, the accumulation of silver was observed in differentorgans. As expected, most of the nanosilver was excreted via fecesand minor amounts were detected in intestine and colon. Orallyadministered ionic silver was detected in feces and additionally inthe urine. Remarkably, also after intravenous injection of nanosil-ver silver was found in feces, which suggests biliary excretion ofsilver nanoparticles.
It is concluded that the oral resorption of nanosilver results inan accumulation of silver in different organs and feces and theintravenous application suggests a biliary excretion.
http://dx.doi.org/10.1016/j.toxlet.2014.06.659
P-3.147The role of coating materials and zeta potentialin iron oxide nanoparticle translocation inhuman intestinal cells
Dajana Lichtenstein 1, Annabelle Bertin 2, Doreen Fiedler 1, SabineHorzowski 1, Richard Palavinskas 1, Birgit Niemann 1, AndreasThünemann 2, Alfonso Lampen 1,∗
1 Federal Institute for Risk Assessment, Berlin, Germany, 2 FederalInstitute for Materials Research and Testing, Berlin, Germany
Due to the more popular use of engineered nanoparticles (ENPs)for food-associated products e.g. in dietary supplements, consumerexposure rises increasingly. Therefore further knowledge aboutuptake of ENPs after oral exposure is of imperative need. Here,the uptake and transport across the intestinal barrier are the mostimportant aspects and especially the coating of ENPs plays a crucialrole.
