title: Concurrent quantitative HPLC-mass spectrometry profiling of small selenium species in human serum and urine after ingestion of selenium supplements.
abstract: Selenium metabolic patterns in the human body originating from five distinct selenium dietary sources, selenate, selenite, selenomethionine (SeMet), methylselenocysteine (MeSeCys) and selenized yeast, were investigated by performing concurrent HPLC-mass spectrometric analysis of human serum and urine. Total selenium and selenium species time profiles were generated by sampling and analyzing serum and urine from volunteers treated with selenium supplements, up to 5 and 24h following ingestion, respectively. We found that an increase in total serum selenium levels, accompanied by elevated selenium urinary excretion, was the common pattern for all treatments, except for that of selenite supplementation. Selenosugar 1 was a universal serum metabolite in all treatments, indicating that ingested selenium is favorably metabolized to the sugar. Except for selenite and selenized yeast ingestion, these patterns were reflected in the urine time series of the different treatments. Selenosugar 1 was the major selenium species present in urine in all treatments except for the selenate treatment, accounting for about 80% of the identified excreted species within 24h of ingestion. Furthermore, the urinary metabolite trimethylselenonium ion (TMSe) was detected for the first time in human background serum by using HPLC coupled to elemental and molecular mass spectrometry. The concurrent monitoring of non-protein selenium species in both body fluids provides the relation between bioavailability and excretion of the individual ingested species and of their metabolic products, while the combined use of elemental and molecular mass spectrometry enables the accurate quantitation of structurally confirmed species. This successfully applied approach is anticipated to be a useful tool for more extensive future studies into human selenium metabolism.
authors: University of Graz, Institute of Chemistry, Analytical Chemistry, NAWI Graz, Universitaetsplatz 1, A-8010 Graz, Austria.
authors: Sabine
authors: S
authors: Kokarnig
authors: University of Crete, Department of Chemistry, Voutes Campus, GR-71003 Heraklion, Crete, Greece.
authors: Alexandra
authors: A
authors: Tsirigotaki
authors: University of Graz, Institute of Chemistry, Analytical Chemistry, NAWI Graz, Universitaetsplatz 1, A-8010 Graz, Austria.
authors: Tanja
authors: T
authors: Wiesenhofer
authors: University of Graz, Buero für ArbeitnehmerInnenschutz und Sicherheit, Halbaerthgasse 6, A-8010 Graz, Austria.
authors: Verena
authors: V
authors: Lackner
authors: University of Graz, Institute of Chemistry, Analytical Chemistry, NAWI Graz, Universitaetsplatz 1, A-8010 Graz, Austria.
authors: Kevin A
authors: KA
authors: Francesconi
authors: University of Crete, Department of Chemistry, Voutes Campus, GR-71003 Heraklion, Crete, Greece.
authors: Spiros A
authors: SA
authors: Pergantis
authors: University of Graz, Institute of Chemistry, Analytical Chemistry, NAWI Graz, Universitaetsplatz 1, A-8010 Graz, Austria. Electronic address: doris.kuehnelt@uni-graz.at.
authors: Doris
authors: D
authors: Kuehnelt
mesh_terms: D000328:Adult; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002852:Chromatography, Ion Exchange; D056148:Chromatography, Reverse-Phase; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D055442:Metabolome; D008875:Middle Aged; D012643:Selenium / Q000008:administration & dosage / Q000097:blood* / Q000737:chemistry / Q000652:urine*; D013997:Time Factors; D055815:Young Adult
chemical_list: D012643:Selenium
keywords: HPLC-mass spectrometry; human serum; human urine; selenium metabolism; speciation