RESUMEN
Free radicals are not only destructive to the living cells but also reduce the quality of animal products through oxidation. As a result the superoxide anion radical (O2-), one of the most destructive reactive oxygen species, is a matter of concern for the animal scientists as well as feed manufacturers to ensure the quality of product to reach consumers demand. The superoxide anion radical scavenging activities (SOSA) of water and MeOH extracts of 2 herbs and 9 pasture samples collected from lowland and highland swards were determined against a 5,5-dimethyl-1-pyroline-N-oxide-O2-spin adduct based on a hypoxanthine-xanthine oxidase reaction using electron spin resonance spectrometry. Both the water and MeOH extracted SOSA differed among the herbs and pastures. Species and altitudinal variations were observed between extraction methods. The herbs were higher in both water and MeOH extracted SOSA than the pastures except for water extracts of one pasture, white clover (Trifolium repens L.). Among the pastures, quackgrass (Agrophyron repens L.) showed higher SOSA in both the MeOH and water extracts, and timothy (Phleum pretense L.) showed higher MeOH extracted SOSA. It is apparent that the kind and amount of antioxidants differ among herbs and pastures. Animal health and quality of animal products could be improved by adequate selection and combining of herbs and pastures having higher SOSA.
Asunto(s)
Espectroscopía de Resonancia por Spin del Electrón/métodos , Depuradores de Radicales Libres/análisis , Poaceae/química , Superóxidos/química , Altitud , Alimentación Animal , Animales , Antioxidantes/análisis , Antioxidantes/química , Antioxidantes/farmacología , Ácido Ascórbico/análisis , Ácido Ascórbico/química , Bovinos , Cromatografía Líquida de Alta Presión , Flavonoides/análisis , Flavonoides/química , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Japón , Metanol/química , Fenoles/análisis , Fenoles/química , Extractos Vegetales/análisis , Extractos Vegetales/química , Polifenoles , Superóxidos/antagonistas & inhibidores , Temperatura , Agua/químicaRESUMEN
This report describes the first cloning and overexpression experiments on genes encoding cAMP-dependent protein kinase catalytic subunits in homobasidiomycete Schizophyllum commune. We used a degenerate PCR approach to identify two novel genes (ScPKAC1 and ScPKAC2) that are very similar to the catalytic subunits in many eukaryotes. The morphological phenotypes of ScPKAC1 and ScPKAC2 overexpressing clones were compared with those of constitutively active ScGP-A overexpressing clones to determine whether ScPKAC1 and ScPKAC2 are located downstream of heterotrimeric G-protein alpha subunit ScGP-A. Overexpression of constitutively active ScGP-A increased intracellular cAMP levels and suppressed aerial mycelium formation. In contrast, overexpressing ScPKAC1 and ScPKAC2 did not affect the intracellular cAMP levels, though aerial mycelium formation was strongly suppressed. These observations suggest that ScPKAC1 and ScPKAC2 proteins are located downstream of the G-protein alpha subunit ScGP-A in the cAMP signaling pathway.
Asunto(s)
Proteínas Quinasas Dependientes de AMP Cíclico/genética , Schizophyllum/enzimología , Schizophyllum/genética , Northern Blotting , Clonación Molecular , Medios de Cultivo , Proteínas Quinasas Dependientes de AMP Cíclico/biosíntesis , Proteínas Quinasas Dependientes de AMP Cíclico/química , ADN de Hongos/biosíntesis , ADN de Hongos/genética , Regulación Enzimológica de la Expresión Génica/genética , Regulación Fúngica de la Expresión Génica/genética , Isoenzimas/biosíntesis , Isoenzimas/química , Isoenzimas/genética , Datos de Secuencia Molecular , Plásmidos/genética , ARN de Hongos/biosíntesis , ARN de Hongos/genética , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Schizophyllum/ultraestructura , Transducción de Señal/genética , Transformación GenéticaRESUMEN
In many fungi, the heterotrimeric G protein alpha subunits, and/or small G protein (RAS) control intracellular cAMP levels. But it is not clear which types of G proteins modulate cAMP levels in homobasidiomycete (mushrooms). To explain the mechanism, we expressed dominant active RAS (a homolog of S. cerevisiae RAS1) in homobasidiomycete Schizophyllum commune and compared the cAMP levels in the transformed clones with those of clones expressing dominant active heterotrimeric G protein alpha subunits ScGP-A, B, and C. The results demonstrated that the dominant active ScGP-A and C elevated the intracellular cAMP levels. In contrast, the dominant active S. commune RAS gene did not affect the cAMP levels, even though colony growth and formation of fruiting bodies were apparently repressed. These data suggest that the heterotrimeric G protein alpha subunits are involved in the mechanism of cAMP regulation, and that RAS modulates another signal-transduction pathway regulating cell growth and differentiation.
Asunto(s)
AMP Cíclico/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiología , Subunidades alfa de la Proteína de Unión al GTP/genética , Subunidades alfa de la Proteína de Unión al GTP/fisiología , Schizophyllum/metabolismo , Sustitución de Aminoácidos , Secuencia de Bases , Clonación Molecular , Cuerpos Fructíferos de los Hongos/metabolismo , Cuerpos Fructíferos de los Hongos/fisiología , Proteínas Fúngicas/metabolismo , Subunidades alfa de la Proteína de Unión al GTP/metabolismo , Expresión Génica , Vectores Genéticos , Datos de Secuencia Molecular , Micelio/metabolismo , Micelio/fisiología , Plásmidos , Mutación Puntual , Schizophyllum/genética , Transducción de Señal , Proteínas ras/genética , Proteínas ras/metabolismo , Proteínas ras/fisiologíaRESUMEN
Among ethanol extracts of 10 edible berries, bilberry extract was found to be the most effective at inhibiting the growth of HL60 human leukemia cells and HCT116 human colon carcinoma cells in vitro. Bilberry extract induced apoptotic cell bodies and nucleosomal DNA fragmentation in HL60 cells. The proportion of apoptotic cells induced by bilberry extract in HCT116 was much lower than that in HL60 cells, and DNA fragmentation was not induced in the former. Of the extracts tested, that from bilberry contained the largest amounts of phenolic compounds, including anthocyanins, and showed the greatest 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. Pure delphinidin and malvidin, like the glycosides isolated from the bilberry extract, induced apoptosis in HL60 cells. These results indicate that the bilberry extract and the anthocyanins, bearing delphinidin or malvidin as the aglycon, inhibit the growth of HL60 cells through the induction of apoptosis. Only pure delphinidin and the glycoside isolated from the bilberry extract, but not malvidin and the glycoside, inhibited the growth of HCT116 cells.