To further elucidate the metabolism of Se, five low molecular weight species of selenium were investigated regarding their toxicological effects, cellular bioavailability and species-specific metabolism in human cells.
Background:
Se is an essential element and traces of this element is an integral component of our diet. On the other hand, Se is also toxic, and the toxic levels are relatively close to optimum nutritional levels (less than a factor of ten). Thus, Se supplementation is not an easy task and requires an individualized approach. To make things even more complicated, the either adverse or beneficial health effects strongly depend on the ingested Se species. In order to understand the metabolic transformation of Se species, the toxicity of the metabolites is of fundamental interest.
The new study:
A mixed German/Austrian research group investigated for the first time the bioavailability and cytotoxicity of the urinary metabolites methyl-2-acetamido-2-deoxy-1-seleno-ß-D-galactopyranoside (selenosugar 1) and trimethylselenonium ion (TMSe) in comparison to the food relevant species methylselenocysteine (MeSeCys), selenomethionine (SeMet) and selenite in human urothelial, astrocytoma and hepatoma cells. While the food relevant species exerted substantial cytotoxicity, the metabolites did not in any of the investigated cell line. This supports their importance for Se detoxification. Interestingly, there was no correlation between the potencies of the respective toxic effects and the measured cellular Se concentrations, highlighting the importance of the Se speciation for toxicity.
The cited study:
Talke Anu Marschall, Julia Bornhorst,
Doris Kuehnelt,
Tanja Schwerdtle,
Differing cytotoxicity and bioavailability of selenite, methylselenocysteine, selenomethionine, selenosugar 1 and trimethylselenonium ion and their underlying metabolic transformations in human cells, Mol. Nutr. Food Res., (2016).
doi: 10.1002/mnfr.201600422
Used analytical techniques (and instruments):
HPLC-ICP-MS Agilent 8800 ICP-MS Related studies (newest first): J.K. Wrobel, R. Power, M. Toborek,
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Human metabolism and renal excretion of selenium compounds after oral ingestion of sodium selenite and selenized yeast dependent on the trimethylselenium ion (TMSe) status. Arch. Toxicol., 90/1 (2016) 149-158.
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K. Francesconi, K. Broberg,
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doi: 10.3945/ajcn.115.114157 Sougat Misra, Mallory Boylan, Arun Selvam, Julian E. Spallholz, Mikael Björnstedt,
Redox-Active Selenium Compounds—From Toxicity and Cell Death to Cancer Treatment, Nutrients, 7 (2015) 3536-3556;
doi:10.3390/nu7053536 S. Kokarnig, A. Tsirigotaki, T. Wiesenhofer, V. Lackner,
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Which form is that? The importance of selenium speciation and metabolism in the prevention and treatment of disease, Chem. Soc. Rev., 42/23 (2013)8870-94.
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Carolin S. Hoefig, Kostja Renko, Josef Köhrle, Marc Birringer, Lutz Schomburg,
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Related EVISA Resources
Brief summary: Speciation and Toxicity Brief summary: ICP-MS: A versatile detection system for speciation analysis Brief summary: LC-ICP-MS: The most often used hyphenated system for speciation analysis Brief summary: ESI-MS: The tool for the identification of species Link database: Toxicity of organic selenium species Link database: Toxicity of inorganic selenium species Link database: Human exposure from selenium in the diet Link Page: All about food science Link database: Selenium and Human health Link database; Research projects related to selenium Material database: Materials for Selenium speciation analysis
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August 2, 2005: New CRM for Selenomethionine in yeast developed by NRC Canada is now on the market last time modified: September 24, 2024
