In vitro evaluation of selenium genotoxic, cytotoxic, and protective effects: a review

Abstract

Selenium is an oligoelement with essential biological functions. Diet is the most important selenium source, and intake of this element depends on its concentration in food and amount of food consumed. Among the essential human micronutrients, selenium is peculiar due to its beneficial physiological activity and toxicity. It may have anticarcinogenic effects at low concentrations, whereas at concentrations higher than those necessary for nutrition, it can be genotoxic and carcinogenic. Because of that, selenium is probably the most widely investigated of all the oligonutrients. In the last decades, there has been increasing interest in several nutritional Se compounds because of their environmental, biological, and toxicological properties, particularly for their cancer- and disease-preventing activities. This article gives an overview of the results of in vitro studies on mutagenicity, genotoxicity, cytotoxicity, and DNA repair conducted within the last decades with different organic and inorganic selenium compounds. Results from these studies provide a better knowledge on the selenium activity and help to elucidate the reasons underlying its duality in order to regulate its correct use in nutrition and clinic.

Influence of domestic processing on the bioaccessibility of selenium from selected food grains and composite meals

“…Selenium deficiency has now been recognized as a global problem which needs to be addressed (Valdiglesias et al 2010). The role of selenium for maintenance of health and the prevention of several diseases is probably more important than it was realised until now (Clark et al 1996;Ip 1998).…”

Optimising Selenium for Modulation of Cancer Treatments

“…Furthermore the toxicities of supranutritional doses of the different Se compounds in clinical use have not been systematically evaluated. Of particular concern is the genotoxicity of some forms of Se, particularly the inorganic salts (14), and the possibility that using these in conjunction with other genotoxic therapies (such as radiation and alkylating agents) could increase the risk of second malignancies and myelodysplasia. No clinical trials to date have reported on such end-points.…”

“…Animal laboratory studies have shown that the organic forms of Se are both more effective and safer than the commonly-used inorganic forms such as sodium selenite (SS), which are more genotoxic (14). From 50% lethal dose (LD 50 ) determinations, SS was found to be fourfold more toxic than SLM when administered to mice intravenously and three-fold more toxic than Se-yeast when given orally to rats (17).…”

Nanotoxicology and oxidative stress control: cutting-edge topics in toxicology

“…However, at concentrations higher than needed for nutrition, selenium proves to be genotoxic and carcinogenic. This study may help regulate the use of selenium in nutrition (6) Valdiglesias et al (2010) Silver nanoparticles (AgNPs) caused a concentration-dependent increase in reactive oxygen species (ROS), mitochondrial damage, DNA adducts and apoptosis in a human alveolar cell line. Pre-treatment with antioxidants reduced ROS as well as DNA adducts underlining the relevance of ROS in toxicity of AgNPs.…”