Organic and inorganic selenium compounds produce different protein patterns in the blood plasma of rats

Some selenium compounds offer important health benefits when administered at supranutritional doses, such as improvement of the immune system and of male fertility, and the prevention of some types of cancer. The traditional selenium indexes do not account for the metabolic status of this element among replete individuals. As a consequence, there is a need for new indexes that distinguish between repletion statuses of selenium. The aim of this work was to indentify some plasmatic proteins that respond to supranutritional doses of selenium, which could be proposed as new protein markers of selenium intake. The effect on rats of dietary supplementation with either selenomethylselenocysteine (SMSeC) or sodium-selenate on some blood plasma proteins was investigated. Two experimental groups consisting of six rats each were fed a basic diet supplemented with either SMSeC or sodium-selenate at 1.9 mg-Se / g-diet for ten weeks. The control group was fed a diet that contained the recommended selenium dose (0.15 mg-Se / g-diet). The changes in the abundance of a group of plasmatic proteins were quantified and analysed statistically. Haptoglobin, apolipoprotein E and transthyretin increased their abundance after diet supplementation with either form of selenium. HNF6 was responsive only to SMSeC, whereas fibrinogen responded only to sodium-selenate. We postulate that the protein patterns observed in this work could be proposed as new molecular biology-based markers of selenium intake.

Assessment of Selenium Status in Adult Females According to Life Cycle

Selenium is a strong antioxidant trace mineral, scavenging free radicals. The prevalence of chronic degenerative diseases is increasing in Korean adults with increasing age. The increased cell damage from free radicals has been implicated in the etiology of these diseases, and evidence is accumulating that the low selenium status that comes with advanced aged is involved in the prevalence of age-associated diseases. However, little is known about the selenium status of Koreans, its age-related change and its relationship to dietary nutrient intake. In this study, the serum selenium levels of healthy adult females according to life cycle and its association with blood albumin levels and nutrient intake were examined. Serum selenium level was measured with the Huwo research reactor using the neutron activation analysis method (NAA). The overall proportion of women with selenium deficiency, serum selenium concentrations below 7.0 microgram/dl, was 9.4%. The average serum selenium levels were 12.39 microgram/dl, 9.45 microgram/dl and 9.16 microgram/dl in the young adult, middle-aged and elderly groups, respectively, showing a reduction of selenium status with advancing age. Selenium deficiency was seen only in the elderly group. Generally, serum selenium levels positively or negatively correlated with nutrient intake, but these association patterns differed depending on the age. The nutrients that showed positive correlations with selenium levels were proteins and phosphate in the young adult group (p<0.05, p<0.05), and total calcium, potassium and vegetable-origin calcium in the middle-aged group. Vitamin C and fiber were the negative correlated nutrients with serum selenium levels in the elderly group (p<0.05, p<0.05). Multiple stepwise regression analysis of the determining factors responsible for selenium status showed that age and serum albumin levels were important factors which explained up to 26.9% variances in serum selenium levels. The average selenium concentrations of Korean adult female subjects were above the deficiency levels in all three age groups. There was a tendency toward decreasing selenium levels as the age of the subjects increased. The factors with the strongest in-fluence on selenium status in healthy adult Korean females were age and serum protein status.