RESUMEN
INTRODUCTION: Prenatal ethanol exposure compromises fetal growth by impairing placentation. Invasive trophoblastic cells, which mediate placentation, express the insulin-IGF regulated gene, aspartyl-asparaginyl ß-hydroxylase (ASPH), which has a critical role in cell motility and invasion. The aims of this study were to characterize effects of ethanol on trophoblastic cell motility, and assess ethanol dose-dependent impairments in placentation and fetal development. METHODS: Pregnant Long Evans dams were fed with isocaloric liquid diets containing 0%, 8%, 18% or 37% ethanol (caloric content) from gestation day (GD) 6 to GD18. Fetal development, placental morphology, density of invasive trophoblasts at the mesometrial triangle, as well as placental and mesometrial ASPH and Notch-1 protein expression were evaluated. Directional motility of control and ethanol-exposed HTR-8/SVneo cells was assessed by ATP Luminescence-Based assay. RESULTS: Severity of fetal growth impairment correlated with increasing doses of ethanol. Ethanol exposure produced dose-dependent alterations in branching morphogenesis at the labyrinthine zone, and inhibited physiological transformation of maternal arteries. ASPH and Notch-1 protein expression levels were reduced, corresponding with impairments in placentation. DISCUSSION: Prenatal ethanol exposure compromises fetal growth and placentation in a dose-responsive manner. Ethanol's adverse effects on placental development are mediated by: (1) altered branching morphogenesis in labyrinthine zone; (2) suppression of invasive trophoblastic precursor cells; and (3) inhibition of trophoblastic cell adhesion and motility, corresponding with reduced ASPH and Notch-1 protein expression.
Asunto(s)
Depresores del Sistema Nervioso Central/efectos adversos , Etanol/efectos adversos , Desarrollo Fetal/efectos de los fármacos , Oxigenasas de Función Mixta/metabolismo , Trofoblastos/efectos de los fármacos , Animales , Adhesión Celular/efectos de los fármacos , Línea Celular , Movimiento Celular/efectos de los fármacos , Depresores del Sistema Nervioso Central/administración & dosificación , Implantación del Embrión/efectos de los fármacos , Etanol/administración & dosificación , Femenino , Humanos , Exposición Materna/efectos adversos , Placentación/efectos de los fármacos , Embarazo , Ratas Long-Evans , Receptor Notch1/metabolismo , Trofoblastos/metabolismoRESUMEN
The present study applies the approach described in Mark et al. for the testing of toxic chemicals produced during the drying of Douglas-fir. The genotoxic potential of Douglas-fir condensate has been previously unexplored and is thus an area of appropriate concern to the forest products industry, regulatory, agencies, and the general public. Previous research conducted in this laboratory has identified two wood-drying condensates that yield positive cytotoxic and genotoxic effects. The results of testing Southern yellow pine and Eastern white pine condensates have been reported elsewhere. Douglas-fir condensate, a third wood-drying condensate, was added in vitro in concentrations ranging from 0.1 to 100 microliters/ml to cultures of Chinese Hamster Ovary (CHO-WBL) cells. A dose response curve was observed with this condensate for both cytotoxicity and genotoxicity. The number of viable cells as well as the mitotic index (MI) and proliferative rate index (PRI) varied inversely with dosage. The result of chromosome aberration (Abs) analysis and sister chromatid exchange (SCE) analysis, both cytogenetic measures of genotoxicity, also gave statistically significant results.
Asunto(s)
Supervivencia Celular , Mutágenos/toxicidad , Árboles/química , Animales , Células CHO , División Celular , Aberraciones Cromosómicas , Cricetinae , Metafase , Pruebas de Mutagenicidad , Intercambio de Cromátides HermanasRESUMEN
Eastern white pine is one of the most important commercial species of wood in the Northeast. Condensates extracted from this wood were tested to detect potential cytotoxicity and genotoxicity in Chinese Hamster Ovary (CHO) cells in the absence of S-9 activation. Cytotoxicity was measured by the Trypan blue exclusion assay, mitotic index (MI) and proliferative rate index (PRI). Genotoxicity was measured by the chromosome aberration (CA) assay and sister chromatid exchange (SCE) analysis. Both cytotoxic and genotoxic effects were observed. Laboratory-generated Eastern white pine condensate reduced the viability of CHO cells. The number of viable cells was roughly inversely proportional to dosage over a range of 91 percent to 58 percent survival in treated groups as compared to 2.4 x 10(5) viable cells (100 percent) in the control. The mitotic index (MI) data also showed an inverse correlation with dosage. The highest scorable dose limited by toxicity was determined to be 1 ml of Eastern white pine condensate in a total of 10 ml of medium. Lastly, a dose response curve was observed using the CA assay and also with the SCE analysis. The present findings support results obtained from Ames testing of Eastern white pine condensate and also corroborate results derived from human peripheral-blood lymphocytes.
Asunto(s)
Mutágenos/toxicidad , Madera , Animales , Células CHO , División Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Aberraciones Cromosómicas , Cricetinae , Intercambio de Cromátides Hermanas/efectos de los fármacosRESUMEN
We tested condensates from Southern Yellow Pine for potential cytotoxicity and genotoxicity in CHO-WBL and human peripheral blood lymphocytes (PBL) in the absence of S-9 activation. Cytotoxicity was evaluated by the Trypan blue exclusion assay, mitotic index (MI) and proliferative rate index (PRI). Genotoxicity was measured by the chromosome aberration (CA) assay and sister chromatid exchange (SCE) analysis. Both cytotoxic and genotoxic effects were observed. Laboratory-generated Southern Yellow Pine condensate reduced the viability of CHO-WBL cells. The number of viable cells was roughly inversely proportional to dosage over a range of 100% to 31% in treated groups, in both experiments, as compared to 2.6 x 10(5) (100%) in the control. The MI data in both CHO cells and PBL also showed an inverse correlation. The highest scorable dose limited by toxicity was determined to be 1 ml of Southern Yellow Pine condensate in 10 ml total of medium. Lastly, a dose response curve was observed in CHO cells, as well as in PBL, using the CA assay and also with the SCE analysis. The present findings corroborate the results from Ames testing and represent the only information currently available on the genotoxic potential of these chemicals.
Asunto(s)
Aberraciones Cromosómicas , Contaminantes Ambientales/toxicidad , Residuos Industriales , Madera , Animales , Células CHO , Supervivencia Celular/efectos de los fármacos , Cricetinae , Relación Dosis-Respuesta a Droga , Humanos , Linfocitos/efectos de los fármacos , Masculino , Índice Mitótico , Intercambio de Cromátides HermanasRESUMEN
Condensate from eastern white pine, one of the commercially most important species of tree in the northeastern United States, was treated for potential cytotoxicity and genotoxicity in human peripheral blood lymphocytes in the absence of S-9 activation. Cytotoxicity was evaluated by mitotic index (MI) determination and proliferative rate index. Genotoxicity was measured by the chromosome aberration (CA) assay and sister chromatid exchange (SCE) analysis. Both cytotoxic and genotoxic effects were observed with laboratory-generated eastern white pine condensate. The MI data showed an inverse correlation between the MI and treatment dosage. A dose response curve was observed using the CA assay and also with the SCE analysis. The present findings thus corroborate the results from Ames testing and represent the only information currently available on the cytotoxic and genotoxic potential of these chemicals.
Asunto(s)
Aberraciones Cromosómicas/inmunología , Citotoxinas/efectos adversos , Contaminantes Ambientales/toxicidad , Linfocitos/efectos de los fármacos , Madera , División Celular/efectos de los fármacos , Citotoxinas/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Humanos , Linfocitos/citología , Linfocitos/fisiología , Masculino , Intercambio de Cromátides Hermanas/efectos de los fármacos , Árboles/químicaRESUMEN
Following upon earlier work the response of MCF-7 breast cancer cells to mitomycin C, a known genotoxicant, was examined. This previous research has yielded a baseline of chromosome aberrations in human peripheral blood lymphocytes from which comparisons can now be made. Results of genotoxicity testing conducted with the same protocol yielded a significantly increased level of chromosome aberrations in MCF-7 cells than in normal human peripheral blood lymphocytes. Dose response curves are presented. Although these results need to be confirmed and extended, the hypothesis is proposed that the present findings are simply another manifestation of the genetic instability inherent in these cancer cells. This seems to be the only known published study of breast cancer cells addressing this issue using the techniques of cytogenetics.
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Adenocarcinoma/patología , Neoplasias de la Mama/patología , Aberraciones Cromosómicas , ADN de Neoplasias/efectos de los fármacos , Mitomicina/toxicidad , Mutágenos/toxicidad , Adenocarcinoma/genética , Neoplasias de la Mama/genética , Daño del ADN , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Linfocitos/efectos de los fármacos , Pruebas de Mutagenicidad , Células Tumorales Cultivadas/efectos de los fármacosRESUMEN
A major activity of the lumber industry is the kiln-drying of wood. In order to ascertain whether wood-drying condensates pose a possible environmental hazard, the cytotoxicity and genotoxicity of these condensates in vitro, were tested using an assay validated using Chinese hamster ovary (CHO) cells and a known genotoxicant, mitomycin C. Subsequently, the assay was developed for the human peripheral blood lymphocyte (HPBL) system, as it was felt that results derived from human cells would reflect the situation more closely in vivo. Condensates from Southern yellow pine, Eastern white pine and Douglas fir trees were tested in CHO and HPBL systems and have demonstrated cytotoxic and genotoxic effects in vitro, as reported elsewhere. Red oak condensate has also been tested using the HPBL system. Thus far, results are consistent with the hypothesis that there is no difference between the cytotoxic and genotoxic effects of treated cells versus controls. This finding indicates either that the condensate of red oak poses no appreciable genetic hazard as measured by cytotoxicity and genotoxicity assays, or that the condensate has lost its potency with time and storage; both of these possibilities have important environmental implications.
Asunto(s)
Contaminantes Ocupacionales del Aire/toxicidad , Contaminantes Atmosféricos/toxicidad , Células CHO/efectos de los fármacos , Residuos Industriales/efectos adversos , Linfocitos/efectos de los fármacos , Pruebas de Mutagenicidad , Madera , Animales , Células Cultivadas , Aberraciones Cromosómicas , Cricetinae , Cricetulus , Calor , Humanos , Índice Mitótico/efectos de los fármacos , Intercambio de Cromátides Hermanas/efectos de los fármacos , Especificidad de la Especie , Factores de Tiempo , VolatilizaciónRESUMEN
In vitro cytogenetics has been established as a valid method for evaluating the genotoxic potential of chemical agents. Armstrong et al have described a simple, quantitative approach to in vitro cytotoxicity and genotoxicity testing by using Chinese hamster ovary (CHO) cells. This approach can also be sensitive and repeatable in an inter-laboratory setting, a prerequisite for routine testing of compounds suspected of having genotoxic properties. In the present study, cytotoxicity was evaluated by the parameter of mitotic index (MI). Genotoxicity is measured by the chromosome aberration (Abs) assay as described by Armstrong et al using CHO cells. The basic analytic principles proposed were extended to include human lymphocytes. Sister chromatid exchange (SCE) analysis was used to establish an additional endpoint. Mitomycin C (MMC), an established clastogen, was used as the model compound for protocol validation. Dose response curves for MI and Abs in CHO cells were found to be consistent with those reported by Armstrong et al. Results from our extended study on lymphocytes and using SCE analysis were analogous. Our experience is that this standardized approach is indeed sensitive and reliable and can serve as a basis for an inter-laboratory testing program.