"It is vox populi that doctors around the world recommend selenium supplements to complement traditional therapy against cancer and the AIDS virus but the truth is that the basics of these properties are not clear," explains to SINC Justo Giner, a chemist from the University of Oviedo (Spain).
"Even the general metabolism of selenium has not been completely cleared up," adds Giner who, along with other researchers at the same university and the University of Pharmaceutical Sciences of Copenhagen (Denmark), has developed a new methodology for discovering how this element moves around living organisms. The study has been published in the March issue of the 'Analytical and Bioanalytical Chemistry' journal.
The in vivo study was carried out on laboratory rats, which were administered a stable metabolic tracer of enriched selenium (77Se). According to the researcher, "it opens the door for transferring this method to clinical trials on humans given that innocuous, non-radioactive isotopes are used."
In line with expected findings, the results reveal that selenium concentrations in biological tissue, blood and urine samples can indeed be analysed. Therefore, mass spectrometry techniques are employed along with a second isotopic tracer (74Se), which helps to quantify "with unequivocal precision" infinitesimal amounts of selenium in its different chemical forms that are distributed by the body.
Selenium is an antioxidant and plays an important role in the body's immune response. Understanding the path that it takes from the moment it is administered to when it is excreted could help to clarify its metabolism and its possible protecting effect against cancer and HIV.
The ideal dose of selenium
The main sources of selenium come from foods such as yeasts, animal products (meat, seafood, dairy products) and vegetables like broccoli, wheat-germ, nuts (especially Brazil nuts), oats, garlic and barley. The current recommended daily intake of selenium is approximately 55 micrograms for women and 70 micrograms for men.
Selenium deficiency is associated with different pathologies like endemic cardiomyopathy, cystic fibrosis, multiple sclerosis, rheumatoid arthritis, haemolysis and muscular dystrophy. Furthermore, thyroid metabolism is affected by selenium levels since the glands deiodinasa enzymes are in fact selenoproteins.
In contrast though, when intake is higher than nutritional requirements, selenium is considered a 'nutraceutical'. Mainly thanks to its antioxidant properties this means that it is beneficial for the health as long as it does not surpass the threshold in which it starts to become toxic.
Kristoffer Lunøe, Justo Giner Martínez-Sierra, Bente Gammelgaard, J. Ignacio García Alonso. "Internal correction of spectral interferences and mass bias for selenium metabolism studies using enriched stable isotopes in combination with multiple linear regression". Analytical and Bioanalytical Chemistry 402 (9): 2749�, March 2012. Doi: 10.1007/s00216-012-5747-7.
SINC | EurekAlert!
Millions through license revenues
27.04.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn
New High-Performance Center Translational Medical Engineering
26.04.2017 | Fraunhofer ITEM
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
28.04.2017 | Event News
20.04.2017 | Event News
18.04.2017 | Event News
28.04.2017 | Medical Engineering
28.04.2017 | Earth Sciences
28.04.2017 | Life Sciences