RESUMEN
Different toxic doses of selenium and monensin preparations were administered to broiler chickens. The two substances were given by oral route, alone or concurrently, for variable periods. Erythrocyte glutathione peroxidase (GSH-Px) activity was found to be elevated after the administration of the drugs. This increase was considerably higher when selenium and monensin were administered concurrently, indicating the occurrence of strong interaction between them. Administration of selenium led to a rapid increase in the liver selenium concentration. This increase, in turn, was enhanced by concurrent application of monensin. Monensin given alone did not have any significant effect on the changes of liver selenium concentration. Further results suggest that administration of monensin increases erythrocyte GSH-Px activity, even in the absence of supplemental selenium or during increased liver selenium concentration.
Asunto(s)
Antiprotozoarios/toxicidad , Eritrocitos/efectos de los fármacos , Glutatión Peroxidasa/metabolismo , Hígado/efectos de los fármacos , Monensina/toxicidad , Selenio/toxicidad , Administración Oral , Animales , Antiprotozoarios/administración & dosificación , Pollos , Interacciones Farmacológicas , Eritrocitos/enzimología , Eritrocitos/patología , Hígado/metabolismo , Hígado/patología , Monensina/administración & dosificación , Selenio/administración & dosificación , Selenio/metabolismoRESUMEN
OBJECTIVE: To study the variation in selenoprotein P levels in serum among healthy subjects from 17 European regions representing nine countries. SUBJECTS: Survey of 414 37-70-year-old subjects (197/217 males/females) from 17 regions. RESULTS: The level of selenoprotein P varied significantly among regions and countries. When the highest concentration of selenoprotein P encountered in samples from Maldegem (Belgium), was set at 100%, the mean concentration for other regions was: 92% Barcelona; 91% Ipswich and London; 89% Malmö and Vosselaan; 86% Lisbon; 85% Netherlands; 83% Umeå; 82% Uppsala; 80% Paris; 79% Heidelberg; 78% Gothenburg and Grenoble; 74% Giessen; 71% Ioannina and 69% Epirus. When the data were pooled for the nine countries the highest selenoprotein P concentration was observed for subjects from Spain. When this concentration was set at 100%, the mean concentration for other countries was: 99% Belgium and United Kingdom, 94% Portugal, 92% Netherlands and Sweden, 86% France, 83% Germany and 76% Greece. The linear correlation between serum selenium and serum selenoprotein P in the whole sample was 0.68, P < 0.001 (n = 414), and it was similar in men and women. Despite this high correlation the mean ratio between selenoprotein P and selenium varied 1.3-fold among regions. CONCLUSIONS: Both the concentration of selenoprotein P as well as its proportion of total serum selenium in adult subjects vary among different European regions. Further studies are necessary to evaluate the physiological or medical implications of these differences.
Asunto(s)
Proteínas/análisis , Adulto , Anciano , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radioinmunoensayo , Selenoproteína P , SelenoproteínasRESUMEN
Whole-blood and plasma selenium (Se) concentrations, red blood cell and plasma glutathione peroxidase activities, and red blood cell glutathione concentrations were investigated in 49 healthy pregnant women. Mean whole-blood and red blood cell Se concentrations started to decline after the 16th week and plasma Se after the 26th week of pregnancy. The lowest values were noted just before delivery. Negative correlations were found between the gestational age and both whole-blood and plasma Se concentrations: (r = -0.560 (p < 0.001) and r = -0.553 (p < 0.001), respectively. Plasma and red blood cell glutathione peroxidase activities started to decrease after the 20th and 30th week of pregnancy, respectively, and before delivery were significantly lower (p < 0.001) than during the 10th week of pregnancy. The red blood cell glutathione concentration increased significantly just before delivery. These results seem to confirm the supposition that in pregnant women with low or even moderate blood Se concentrations the requirement for the element significantly increases.
Asunto(s)
Glutatión Peroxidasa/sangre , Glutatión/sangre , Embarazo/sangre , Selenio/sangre , Adulto , Eritrocitos/enzimología , Eritrocitos/metabolismo , Femenino , Humanos , Trabajo de Parto/sangre , Primer Trimestre del Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del EmbarazoRESUMEN
Recent prospective epidemiological studies have shown an association between a low prediagnostic serum selenium (Se) concentration and the risk of cancer. Se concentrations in whole blood and plasma, and the activity of red cell and plasma glutathione peroxidase (GSH-Px) were measured in patients with breast cancer, gastric cancer and colorectal cancer. The observed whole blood and plasma Se concentrations of healthy persons were 99.5 and 78.5 micrograms/L, respectively. Red cell and plasma GSH-Px activities of this group were: 21.0 U/g Hb and 256 U/L plasma. In all investigated cancer patients significantly lower whole blood and plasma Se concentrations, and significantly lower red cell and plasma GSH-Px activities were found, as compared with the values of healthy controls. Low Se concentrations of blood components may be indicative of increased cancer risk.