title: Elemental selenium at nano size (Nano-Se) as a potential chemopreventive agent with reduced risk of selenium toxicity: comparison with se-methylselenocysteine in mice.
abstract: Selenium (Se) is an essential trace element with a narrow margin between beneficial and toxic effects. As a promising chemopreventive agent, its use requires consumption over the long term, so the toxicity of Se is always a crucial concern. Based on clinical findings and recent studies in selenoprotein gene-modified mice, it is likely that the antioxidant function of one or more selenoproteins is responsible for the chemopreventive effect of Se. Furthermore, upregulation of phase 2 enzymes by Se has been implicated as a possible chemopreventive mechanism at supranutritional dietary levels. Se-methylselenocysteine (SeMSC), a naturally occurring organic Se product, is considered as one of the most effective chemopreventive selenocompounds. The present study revealed that, as compared with SeMSC, elemental Se at nano size (Nano-Se) possessed equal efficacy in increasing the activities of glutathione peroxidase, thioredoxin reductase, and glutathione S-transferase, but had much lower toxicity as indicated by median lethal dose, acute liver injury, survival rate, and short-term toxicity. Our results suggest that Nano-Se can serve as a potential chemopreventive agent with reduced risk of Se toxicity.
authors.affiliation: University of Science and Technology of China, Hefei 230052, Anhui, P.R. China.
authors.forename: Jinsong
authors.initials: J
authors.lastname: Zhang
authors.forename: Xufang
authors.initials: X
authors.lastname: Wang
authors.forename: Tongwen
authors.initials: T
authors.lastname: Xu
mesh_terms: D000818:Animals; D016588:Anticarcinogenic Agents / Q000008:administration & dosage / Q000627:therapeutic use* / Q000633:toxicity*; D001682:Biological Availability; D056486:Chemical and Drug Induced Liver Injury / Q000473:pathology; D003545:Cysteine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use / Q000633:toxicity; D004798:Enzymes / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D006128:Growth / Q000187:drug effects; D007202:Indicators and Reagents; D007928:Lethal Dose 50; D008099:Liver / Q000201:enzymology / Q000473:pathology; D008315:Malondialdehyde / Q000378:metabolism; D051379:Mice; D008815:Mice, Inbred Strains; D053758:Nanoparticles / Q000008:administration & dosage / Q000627:therapeutic use* / Q000633:toxicity*; D009747:Nutritional Physiological Phenomena; D016566:Organoselenium Compounds / Q000008:administration & dosage / Q000627:therapeutic use* / Q000633:toxicity*; D012643:Selenium / Q000008:administration & dosage / Q000627:therapeutic use* / Q000633:toxicity*; D017279:Selenocysteine / Q000031:analogs & derivatives; D016019:Survival Analysis
chemical_list: D016588:Anticarcinogenic Agents; D004798:Enzymes; D007202:Indicators and Reagents; D016566:Organoselenium Compounds; D017279:Selenocysteine; D008315:Malondialdehyde; D005982:Glutathione Transferase; D012643:Selenium; D003545:Cysteine; C002979:selenomethylselenocysteine