Home About us Contact
|
Home About us Contact | ||
|
|
||
Genotoxic Damage (genotoxic + damage)
Selected AbstractsGenotoxicity related to transfer of oil spill pollutants from mussels to mammals via foodENVIRONMENTAL TOXICOLOGY, Issue 4 2004Sébastien Lemiere Abstract Heavy fuel oils containing high levels of polycyclic aromatic hydrocarbons (PAHs) were released into the marine environment after the Erika oil spill on the Atlantic coast. As highly condensed PAH pollutants can bioaccumulate in invertebrates, their transfer to vertebrates through the food chain was of concern. This study aimed to estimate potential genotoxic effects in rats fed for 2 or 4 weeks with the marine mussel Mytilus edulis contaminated by oil pollutants. Two levels of PAH contamination were studied, around 100 and 500 ,g of total PAHs/kg dry weight (d.w.) in mussels. Genotoxic damage in rats was investigated by single-cell gel electrophoresis (Comet assay) and micronucleus assays in liver, bone marrow, and peripheral blood. DNA damage was observed in the liver of rats fed with the most contaminated mussels (500 ,g PAHs/kg d.w.).DNA damage also was observed in the bone marrow but less than that in the liver. A small increase in micronuclei frequency was registered as well. This work underlines the bioavailability of pollutants in fuel-oil-contaminated mussels to consumers and the usefulness of the Comet assay as a sensitive tool in biomonitoring to analyze responses to PAH transfer in food. The occurrence of substituted PAHs and related compounds such as benzothiophenes in addition to nonsubstituted PAHs in fuel oils and mussels raised the question of whether they were implicated in the genotoxic effects registered in rats. © 2004 Wiley Periodicals, Inc. Environ Toxicol 19: 387,395, 2004. [source] Review on the effects of exposure to spilled oils on human healthJOURNAL OF APPLIED TOXICOLOGY, Issue 4 2010Francisco Aguilera Abstract Harmful effects of oil spills on diverse flora and fauna species have been extensively studied. Nevertheless, only a few studies have been compiled in the literature dealing with the repercussions of oil exposure on human health; most of them have focused on acute effects and psychological symptoms. The objective of this work was to gather all these studies and to analyze the possible consequences of this kind of complex exposure in the different aspects of human health. Studies found on this topic were related to the disasters of the Exxon Valdez, Braer, Sea Empress, Nakhodka, Erika, Prestige and Tasman Spirit oil tankers. The majority of them were cross-sectional; many did not include control groups. Acute effects were evaluated taking into account vegetative-nervous symptoms, skin and mucous irritations, and also psychological effects. Genotoxic damage and endocrine alterations were assessed only in individuals exposed to oil from Prestige. The results of the reviewed articles clearly support the need for biomonitoring human populations exposed to spilled oils, especially those individuals involved in the cleanup, in order to evaluate not only the possible immediate consequences for their health but also the medium- and long-term effects, and the effectiveness of the protective devices used. Copyright © 2010 John Wiley & Sons, Ltd. [source] Feasibility of conducting the micronucleus test in circulating erythrocytes from different mammalian species: An anatomical perspectiveENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 9 2006Ion Udroiu Abstract The in vivo mammalian micronucleus test can be conducted easily on peripheral blood samples since the maturation of erythrocytes involves the loss of the major nucleus. In addition, mature erythrocytes are relatively long-lived, so that the test potentially can detect genotoxic damage caused by chronic exposures. However, some species have spleens that remove micronuclei from the peripheral circulation, making such measurements problematical. This report summarises haematological and mutagenesis studies dealing with this subject and provides an anatomical interpretation of the phenomenon. Anatomical features can be used to identify those species in which micronuclei are removed by the spleen. Environ. Mol. Mutagen., 2006. © 2006 Wiley-Liss, Inc. [source] BRIEF REPORT: Single exposure to cocaine or ecstasy induces DNA damage in brain and other organs of miceADDICTION BIOLOGY, Issue 1 2010Tathiana A. Alvarenga ABSTRACT We evaluated the overall genetic damage induced by different doses of cocaine and MDMA (3,4-Methylenedioxymethamphetamine) in several organs. One hour after intraperitoneal drug administration, mice were euthanized; peripheral blood, liver and brain were collected, and the cellular suspensions were used for the single cell gel (comet) assay. We determined that all doses of cocaine and MDMA tested were able to induce DNA damage in blood cells. Extensive genotoxic damage was induced by cocaine or MDMA at the highest doses used in liver cells. Brain cells were affected by all doses administrated. These findings demonstrate that cocaine and MDMA are potent genotoxins. [source] Adaptive response of the skin to UVB damage: role of the p53 proteinINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2006L. Verschooten Synopsis Different adaptation mechanisms like heat shock response, cell cycle arrest and DNA repair, melanin pigmentation and thickening of the epidermis are present in the human skin to protect against the adverse effects of solar UV irradiation. When DNA damage is beyond repair, cells undergo apoptosis to prevent their replication. We discuss the current knowledge on these different adaptation mechanisms to UVB damage, the most energetic fraction of solar UV that reaches the skin. As p53 protein, the guardian of the genome, plays a key role in protective response to genotoxic damage, its role in this adaptive response of the skin to UV will be further discussed. Résumé Pour se protéger contre les effets néfastes de l'irradiation UV de la lumière solaire, la peau humaine dispose de différents mécanismes de protection adaptatifs: résistance au choc thermique, arrêt du cycle cellulaire et réparation de l'ADN, pigmentation mélanique et épaississement de l'épiderme. Quand les altèrations dépassent les capacités de réparation, les cellules entrent en apoptose pour empêcher la réplication d'une cellule avec de l'ADN endommagé. Dans cet article, on passe en revue les connaissances actuelles sur les différents mécanismes d'adaptation de la peau aux altérations provoquées par les UVB, la fraction la plus énergétique des UV solaires qui atteint la peau. Puisque la protéine P53, gardienne du génome, joue un rôle clé dans la réponse de protection aux altérations génotoxiques, son rôle dans la réponse d'adaptation de la peau aux UV sera discuté en détail. [source] Antioxidant and antigenotoxic activities of Angelica keiskei, Oenanthe javanica and Brassica oleracea in the Salmonella mutagenicity assay and in HCT116 human colon cancer cellsBIOFACTORS, Issue 4 2006Daejoong Kwon Abstract Epidemiological studies indicate that consumption of green-yellow vegetables rich in chlorophyll, vitamin C, vitamin E, and carotenoids reduce the risk of cancer. We sought to examine the antigenotoxic and antioxidant properties of chlorophyll-rich methanol extracts of Angelica keiskei, Oenanthe javanica, and Brassica oleracea (kale). In the Salmonella mutagenicity assay, A. keiskei caused dose-dependent inhibition against three heterocyclic amine mutagens in the presence of S9, O. javanica was antimutagenic only at the highest concentration in the assay (2 mg/plate), and B. oleracea showed no consistent inhibitory activity at non-toxic levels. None of the extracts were effective against three direct-acting mutagens in the absence of S9. Extracts of A. keiskei and, to a lesser extent O. javanica, inhibited two of the major enzymes that play a role in the metabolic activation of heterocyclic amines, based on ethoxyresorufin-O-deethylase and methoxyresorufin-O-demethylase assays in vitro. All three plant extracts were highly effective in assays which measured ferric reducing/antioxidant power, oxygen radical absorbance capacity, and Fe2+/H2O2 -mediated DNA nicking. Finally, using the ,comet' assay, all three plant extracts protected against H2O2 -induced genotoxic damage in human HCT116 colon cancer cells. These findings provide support for the antigenotoxic and antioxidant properties of chlorophyll-rich extracts of A. keiskei, O. javanica, and B. oleracea, through mechanisms that include inhibition of carcinogen activation and scavenging of reactive oxygen species. [source] New insights into pigmentary pathways and skin cancerBRITISH JOURNAL OF DERMATOLOGY, Issue 1 2010A.J. Miller Summary The ability of cells to respond to and to mitigate environmental stress is crucial for their survival. Constitutive and facultative pigmentation have evolved in order for human skin to contend with high levels of terrestrial ultraviolet radiation (UVR). When this melanin ,shield' is compromised, individuals are exposed to increased skin cancer risk. The purpose of this review is to discuss new insights into the genetic basis of phenotypic risk factors for skin cancer, their connection to pigmentation and tanning, the precise molecular connections linking UVR to the tanning response, and potential methods of modulating pigmentation that avoid genotoxic damage. Highly translational implications of this research include a scientific basis on which to counsel patients regarding the carcinogenicity of UVR exposure related to tanning and potential new tanning agents that may actually protect against skin cancer by circumventing the need for UVR exposure. [source] | |||||||||||||