DNA damage after in vitro exposure to very low concentration of combusted cerium nanoparticles (CoCeO2NPs) and to CoCeO2NPs + Benzo(a)pyrene in rat and human gametes.

International audienceTitre 25 mots 25 DNA damage after in vitro exposure to very low concentration of combusted cerium nanoparticles (CoCeO 2 NPs) and to CoCeO 2 NPs + Benzo(a)pyrene in rat and human gametes. Study question 25 mots 23 Do in vitro gametes exposures to very low concentration of CoCeO 2 NPs and to CoCeO 2 NPs + Benzo(a)pyrene induce significant and similar DNA damage ? Summary answer 25 mots 22 In vitro gametes co-exposure to CoCeO 2 NPs + Benzo(a)pyrene induced statistically higher DNA damage than exposure to CoCeO 2 NPs alone in rat and human. What is known already 100 mots 100 Cerium dioxide nanoparticles (CeO 2 NPs) are widely used as diesel additive and are released in the air after engine combustion. The Organization for Economic Cooperation and Development included CeO 2 NPs in the priority list of nanomaterials requiring urgent evaluation. In vitro exposure of human and mouse sperm and cumulus oocyte complexes (COC) to very low concentrations of pristine CeO 2 NPs induce significant DNA damage. Benzo(a)pyrene (BaP) is also released in the air by diesel combustion and is known to induce DNA damage in sperm and COC. Nevertheless, pristine CeO 2 NPs are modified by combustion; the impact of CoCeO 2 NPs exposure and to CoCeO 2 NPs+BaP remains unexplored. Study design, size, duration 75mots 66 Pristine CeO 2 NPs were extracted from Envirox TM diesel additive and combusted at 850°C, (average combustion temperature in a diesel engine), to obtain CoCeO 2 NPs. Crystalline structure of CoCeO 2 NPs was analysed by X-ray Diffraction. Rat gametes were sampled in epididymis and oviducts after euthanasia of five mature males and fourty 4 weeks old females (after ovarian stimulation). Human frozen sperm from fertile donors were purchased from Germetheque biobank (France)

In Vitro Co Exposure to CeO2 Nanomaterials from Diesel Engine Exhaust and Benzo(a)Pyrene Induces Additive DNA Damage in Sperm and Cumulus Cells but not in Oocytes

International audienceBenzo(a)pyrene (BaP) is a recognized reprotoxic compound and the most widely investigated polycyclic aromatic hydrocarbon in ambient air; it is widespread by the incomplete combustion of fossil fuels along with cerium dioxide nanomaterials (CeO2 NMs), which are used in nano based diesel additives to decrease the emission of toxic compounds and to increase fuel economy. The toxicity of CeO2 NMs on reproductive organs and cells has also been shown. However, the effect of the combined interactions of BaP and CeO2 NMs on reproduction has not been investigated. Herein, human and rat gametes were exposed in vitro to combusted CeO2 NMs or BaP or CeO2 NMs and BaP in combination. CeO2 NMs were burned at 850 °C prior to mimicking their release after combustion in a diesel engine. We demonstrated significantly higher amounts of DNA damage after exposure to combusted CeO2 NMs (1 g L 1) or BaP (1.13 mol L 1) in all cell types considered compared to unexposed cells. Co exposure to the CeO2 NMs BaP mixture induced additive DNA damage in sperm and cumulus cells, whereas no additive effect was observed in rat oocytes. This result could be related to the structural protection of the oocyte by cumulus cells and to the oocyte's efficient system to repair DNA damage compared to that of cumulus and sperm cells

CeO2 Nanomaterials from Diesel Engine Exhaust Induce DNA Damage and Oxidative Stress in Human and Rat Sperm In Vitro

International audienceCerium dioxide nanomaterials (CeO2 NMs) are widely used in nano-based diesel additives to decrease the emission of toxic compounds, but they have been shown to increase the emission of ultrafine particles as well as the amount of released Ce. The Organization for Economic Cooperation and Development included CeO2 NMs in the priority list of nanomaterials that require urgent evaluation, and the potential hazard of aged CeO2 NM exposure remains unexplored. Herein, human and rat sperm cells were exposed in vitro to a CeO2 NM-based diesel additive (called Envirox TM), burned at 850 °C to mimic its release after combustion in a diesel engine. We demonstrated significant DNA damage after in vitro exposure to the lowest tested concentration (1 µg•L −1) using the alkaline comet assay (ACA). We also showed a significant increase in oxidative stress in human sperm after in vitro exposure to 1 µg•L −1 aged CeO2 NMs evaluated by the H2DCF-DA probe. Electron microscopy showed no internalization of aged CeO2 NMs in human sperm but an affinity for the head plasma membrane. The results obtained in this study provide some insight on the complex cellular mechanisms by which aged CeO2 NMs could exert in vitro biological effects on human spermatozoa and generate ROS

IMPACT REPROTOXIQUE D’ADDITIF DIESEL CONTENANT DES NANOPARTICULES DE CERIUM : APPROCHE IN VITRO

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Reproductive toxicity of combusted diesel additive nanoceria

International audienc

IMPACT REPROTOXIQUE D’ADDITIF DIESEL CONTENANT DES NANOPARTICULES DE CERIUM : APPROCHE IN VITRO

International audienc

IMPACT REPROTOXIQUE D’ADDITIF DIESEL CONTENANT DES NANOPARTICULES DE CERIUM : APPROCHE IN VITRO

International audienc

Reproductive toxicity of combusted diesel additive nanoceria

International audienc