RESUMO
Previously, we showed that oral application of the environmental pollutant dibenzo[a,l]pyrene (DB[a,l]P) induces oral tumors in mice. Thus, in the present investigation we examined the effect of alcohol on DB[a,l]P-induced DNA damage and immune regulation; we showed that alcohol (6.4% v/v in the diet, 35% of Calories) significantly enhanced the levels of (-)-anti-trans-DB[a,l]P-dA while decreased the levels of GSH in the mouse oral tissues. Analysis of RNA expression revealed that DB[a,l]P alone upregulates inflammatory genes while alcohol suppresses several markers of immune surveillance. Collectively, these results suggest that alcohol may enhance oral carcinogenesis induced by DB[a,l]P.
Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Benzopirenos/metabolismo , Dano ao DNA , Poluentes Ambientais/metabolismo , Boca/metabolismo , Consumo de Bebidas Alcoólicas/imunologia , Alcoolismo , Animais , Carcinogênese , Camundongos , Boca/imunologia , Neoplasias BucaisRESUMO
We report here a detailed time course study of the individual and combined chemopreventive effects of Tamoxifen (Tam) and a high fish oil (FO) diet on multiple histologic parameters of mammary carcinogenesis. Groups of female Sprague-Dawley rats were injected ip with 1-methyl-1-nitrosourea at 50 days of age and assigned to either a control diet (20% corn oil [CO]) or a FO-rich diet (10% FO + 10% CO) in the presence and absence of Tam in the diet (0.6 ppm). Rats were sacrificed at weeks 4 (before palpable tumors), 8 and 12 (when â¼90% of control rats had palpable tumors). Our results demonstrate a major effect of Tam in inhibiting the development of early preneoplastic lesions. FO, while having a marginal protective effect of it own, enhanced the antitumor action of Tam on all histologic parameters of carcinogenesis, although the effects of the combination were not statistically different from those of Tam alone. The combination of FO and Tam was the only intervention that induced regression of established preneoplastic lesions. We also found that in contrast to plasma, only target tissue n-3 fatty acids (FAs) levels correlated with select tissue biomarkers of carcinogenesis whose expression was altered in a manner predictive of a protective effect. Our results demonstrating the potentially superior chemopreventive efficacy of Tam and n-3FA have important translational implications. Our data also emphasize the importance of local factors in affecting target tissue levels and biologic effects of n-3FA.
Assuntos
Antineoplásicos/farmacologia , Carcinogênese/efeitos dos fármacos , Ácidos Graxos Ômega-3/farmacologia , Neoplasias Mamárias Experimentais/prevenção & controle , Tamoxifeno/farmacologia , Animais , Biomarcadores Tumorais/metabolismo , Carcinogênese/genética , Carcinogênese/metabolismo , Quimioprevenção/métodos , Dieta , Feminino , Óleos de Peixe/farmacologia , Antígeno Ki-67/genética , Glândulas Mamárias Animais/metabolismo , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/metabolismo , Metilnitrosoureia , Lesões Pré-Cancerosas/tratamento farmacológico , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
Se evaluó el comportamiento de los dilutores Tris-yema y Citrato-yema en el congelamiento de semen de ovino y la integridad de la membrana espermática del semen congelado en pajillas. El estudio se realizó en el Banco Nacional de Semen UNALM con seis carneros de tres razas. El semen se colectó en vagina artificial, se diluyó con Tris -glucosa - yema de huevo de Codorniz (Tris) o Citrato - glucosa - yema de huevo (Citrato), se almacenó en pajillas de 0.5 ml, y se congeló en nitrógeno líquido. El descongelamiento se realizó a 38 °C por 15 segundos. En semen refrigerado, la Motilidad Individual Progresiva (MIP) en semen diluido con Tris fue 82.3% y con Citrato de 79.2%, y los valores de la integridad de membrana (HOST) fueron de 78.0 ± 4.4 con Tris y 73.2 ± 5.8% con Citrato. En semen descongelado, la MIP fue de 62.0 y 56.8%, y HOST de 49.8 ± 3.9 y 41.3 ± 3.8% para los dilutores Tris y Citrato, respectivamente, existiendo diferencias significativas entre dilutores, carneros y momentos de procesamiento (p<0.01). Se registraron regresiones lineales significativas (p<0.001) entre MIP del semen refrigerado y HOST de semen descongelado con uso de ambos dilutores. Se concluye que Tris presenta un mejor rendimiento que Citrato para la congelación del semen ovino y que la prueba hipoosmótica permitió evidenciar diferencias entre dilutores, carneros y momentos de procesamiento.
The study evaluated the performance of Tris-egg yolk and Citrate-egg yolk as extenders for freezing ram semen in straws and the integrity of sperm membrane of frozen sperm at the National Semen Bank UNALM, Lima, Peru using six ram semen donors of three breeds. The semen was collected in an artificial vagina, diluted with Tris glucose quail egg yolk (Tris) or with Citrate glucose egg yolk (Citrate), stored in 0.5 ml pellets, and frozen in liquid nitrogen. Thawing was done at 38 ºC for 15 seconds. In refrigerated semen, the Progressive Individual Motility (PIM) in diluted semen with Tris was 82.3% and with Citrate was 79.2%, and the integrity of the cytoplasmic membrane (HOST) was 78.0 ± 4.4 with Tris and 73.2 ± 5.8% with Citrate. In thawed semen, PIM was 62.0 and 56.8%, and HOST was 49.8 ± 3.9 and 41.3 ± 3.8% for Tris and Citrate respectively, with significant differences between extenders, rams and processing period (p<0.01). There were significant lineal regressions (p<0.001) between PIM of refrigerated semen and HOST after thawing for both extenders. It was concluded that Tris showed better performance than Citrate for freezing ram semen, and the hipoosmotic swelling test allowed to show differences between extenders, rams and processing periods.
Assuntos
Animais , Diluição , Gema de Ovo , Ovinos , Preservação do Sêmen , Ácido CítricoRESUMO
El presente estudio tuvo como objetivo evaluar el efecto de dos dilutores, Tris-Fructosa-Yema de huevo (Tris) y Citrato-Glucosa-Yema de huevo (citrato), sobre la motilidad espermática e integridad de la membrana espermática (HOST) en semen congelado de ovinos bajo la forma de pellets. La investigación se llevó a cabo en el Banco de Semen de la Universidad Nacional Agraria La Molina, Lima, empleándose 4 carneros (2 Blackbelly y 2 Assaf) de 3.5 a 4 años de edad. Se empleó el análisis de covariancia para analizar Motilidad Individual Progresiva (MIP), y bloques completamente randomizados para medir el efecto de los dilutores sobre la integridad de la membrana espermática. Para el congelamiento del semen se utilizó hielo seco y el descongelamiento se realizó a 38 ºC en tubos de ensayo. En ovinos Assaf, la MIP del semen descongelado fue de 63.77 y 61.11% utilizando Tris y citrato, respectivamente, encontrándose diferencias significativas (p<0.05) entre dilutores, mientras que en ovinos Blackbelly, la MIP fue de 62.33 y 61.33% con Tris y citrato, respectivamente, sin diferencia estadística. En ovinos Assaf, los valores de HOST del semen descongelado fueron de 43.56 y 40.38% con Tris y citrato, y en Blackbelly fueron de 40.19 y 38.16% con Tris y Citrato, respectivamente, sin diferencias significativas. Se concluye que el dilutor Tris evidenció mejores niveles en la conservación de la motilidad individual espermática pero ambos tuvieron similar efecto en la integridad funcional de la membrana espermática.
The objective of the study was to evaluate the effects of two semen extenders: Tris-Fructose-egg yolk (Tris) and Citrate-Glucose-egg yolk (citrate) on motility and sperm membrane integrity (HOST) in ovine frozen semen in pellets. The study was carried out at the Semen Bank of the Agrarian University La Molina, in Lima, Peru, using 4 rams (2 Assaf and 2 Blackbelly) of 3.5 to 4 years old. A covariance analysis was used to evaluate the effect of the treatment and breed on Individual Progressive Motility (IPM), and randomized block design to evaluate the effect of extenders on sperm membrane integrity. Semen was frozen of dry ice and thawing was done in test tubes at 38 °C. In the Assaf breed, IPM of thawed semen was 63.77 and 61.11% when using Tris and citrate respectively, showing statistical difference (p<0.05). In the Blackbelly breed the IPM was 62.33 and 61.33%, when used Tris and citrate respectively, and without significant difference. In the Assaf the HOST values of thawed semen were 43.56 and 40.38%, while in Blackbelly were 40.19 and 38.16% respectively, both without significant differences. It is concluded that Tris showed better effect on individual motility but both of them had similar effect on sperm membrane integrity.
Assuntos
Animais , Diluição , Motilidade dos Espermatozoides , Ovinos , Preservação do SêmenRESUMO
Se analizó el efecto de los dilutores Tris-glucosa y Ovine Freezing Buffer (UA 466/005238) sobre la motilidad e integridad de la membrana citoplasmática de los espermatozoides durante el proceso de congelación de semen ovino. Se utilizó el semen de cinco carneros (2 Assaf, 2 Canela y 1 Black Belly). El semen fresco fue de buena calidad y los valores de las características seminales estuvieron dentro de los parámetros de la especie. La motilidad individual progresiva (MIP) del semen refrigerado fue 86.0 ± 2.48 y 88.5 ± 4.8% y del semen congelado fue de 60.8 ± 1.9 y 62.9 ± 2.4% con los dilutores Tris y Ovine Freezing, respectivamente; mientras que la proporción de espermatozoides con membrana intacta, evaluada por la prueba de HOST (Hipo Osmotic Swelling Test) fue 77.9 ± 4.8 y 78.9 ± 4.0% para el semen refrigerado y de 39.9 ± 3.6 y 43.2 ± 2.9% para el semen congelado, utilizando los dilutores Tris y Ovine Freezing, respectivamente, existiendo diferencias altamente significativas entre dilutores, carneros y fases del proceso de congelación (p<0.01). Se encontró regresiones lineales significativas (p<0.05) entre HOST de semen fresco y HOST post-descongelado de semen diluido, ya sea con Tris o con Ovine Freezing. Se concluye que el uso del dilutor Ovine Freezing tuvo una mejor respuesta en la calidad espermática durante el proceso de congelación; así mismo, la prueba hipoosmótica demostró ser una buena herramienta como indicador de la calidad de semen.
The effect of two semen extenders: Glucose Tris and Ovine Freezing Buffer (UA 466/005238) on the motility and cytoplasmic membrane integrity of spermatozoa during the freezing process was evaluated. Five rams (2 Assaf, 2 Cinnamon and 1 Black Belly) were used. The fresh semen was of good quality and values of seminal characteristics were within the normal range for this species. The Progressive Individual Motility of the refrigerated semen was 86.0 ± 2.48 and 88.5 ± 4.8% and for frozen semen was 60.8 ± 1.9 and 62.9 ± 2.4% for Tris and Ovine Freezing, respectively; while the proportion of spermatozoa with intact membranes, evaluated by HOST (Hipo Osmotic Swelling Test), was 77.9 ± 4.8 and 78.9 ± 4.0% for refrigerated semen and 39.9 ± 3.6 and 43.2 ± 2.9% for frozen semen using the Tris and Ovine Freezing dilutors, respectively. There were highly significant differences between dilutors, rams and phases of the freezing process (p<0.01). Significant lineal regressions (p<0.05) were found between HOST values of fresh semen and HOST values of thawed semen, either with Tris or Ovine Freezing. It can be concluded that the Ovine Freezing semen extender showed a better performance during the freezing process; moreover, the hypoosmotic test showed to be a good indicator tool for semen quality.