title: Synthetic as compared with natural vitamin E is preferentially excreted as alpha-CEHC in human urine: studies using deuterated alpha-tocopheryl acetates.
abstract: Alpha-CEHC (2,5,7,8-tetramethyl-2(2'-carboxyethyl)-6-hydroxychroman) is a urinary vitamin E metabolite with a truncated phytyl tail. To test whether natural and synthetic vitamin E are similarly converted to alpha-CEHC, 6 humans consumed 150 mg each RRR-alpha-[5-(C2H3)]- and all rac-alpha-[5,7(C2H3)2]-tocopheryl acetates (d3RRR-alpha- and d6all rac-alpha-tocopheryl acetates, respectively). Plasma was collected at 0, 6, 12 and 24 h; urine (24 h) at 0, 1, 2, 3, 4 and 8 days. Following dosing, plasma was enriched with d3RRR-alpha-tocopherol, while urine was enriched with alpha-CEHC derived from d6all rac-alpha-tocopherol. Thus, synthetic compared with natural vitamin E is preferentially metabolized to alpha-CEHC and excreted.
authors.affiliation: Linus Pauling Institute, Oregon State University, Corvallis 97330, USA. maret.traber@orst.edu
authors.forename: M G
authors.initials: MG
authors.lastname: Traber
authors.forename: A
authors.initials: A
authors.lastname: Elsner
authors.forename: R
authors.initials: R
authors.lastname: Brigelius-Flohé
mesh_terms: D000328:Adult; D002839:Chromans / Q000652:urine*; D003903:Deuterium; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011422:Propionates / Q000652:urine*; D024505:Tocopherols; D014810:Vitamin E / Q000031:analogs & derivatives* / Q000097:blood / Q000378:metabolism*; D024502:alpha-Tocopherol / Q000031:analogs & derivatives*
chemical_list: D002839:Chromans; D011422:Propionates; D014810:Vitamin E; C084852:2,5,7,8-tetramethyl-2-(2'-carboxyethyl)-6-hydroxychroman; D003903:Deuterium; D024502:alpha-Tocopherol; D024505:Tocopherols