title: Identification and assessment of markers of biotin status in healthy adults.
abstract: Human biotin requirements are unknown and the identification of reliable markers of biotin status is necessary to fill this knowledge gap. Here, we used an outpatient feeding protocol to create states of biotin deficiency, sufficiency and supplementation in sixteen healthy men and women. A total of twenty possible markers of biotin status were assessed, including the abundance of biotinylated carboxylases in lymphocytes, the expression of genes from biotin metabolism and the urinary excretion of biotin and organic acids. Only the abundance of biotinylated 3-methylcrotonyl-CoA carboxylase (holo-MCC) and propionyl-CoA carboxylase (holo-PCC) allowed for distinguishing biotin-deficient and biotin-sufficient individuals. The urinary excretion of biotin reliably identified biotin-supplemented subjects, but did not distinguish between biotin-depleted and biotin-sufficient individuals. The urinary excretion of 3-hydroxyisovaleric acid detected some biotin-deficient subjects, but produced a meaningful number of false-negative results and did not distinguish between biotin-sufficient and biotin-supplemented individuals. None of the other organic acids that were tested were useful markers of biotin status. Likewise, the abundance of mRNA coding for biotin transporters, holocarboxylase synthetase and biotin-dependent carboxylases in lymphocytes were not different among the treatment groups. Generally, datasets were characterised by variations that exceeded those seen in studies in cell cultures. We conclude that holo-MCC and holo-PCC are the most reliable, single markers of biotin status tested in the present study.
authors.affiliation: Department of Nutrition, University of Nebraska-Lincoln, Lincoln, NE 68583-0806, USA.
authors.forename: Wei Kay
authors.initials: WK
authors.lastname: Eng
authors.forename: David
authors.initials: D
authors.lastname: Giraud
authors.forename: Vicki L
authors.initials: VL
authors.lastname: Schlegel
authors.forename: Dong
authors.initials: D
authors.lastname: Wang
authors.forename: Bo Hyun
authors.initials: BH
authors.lastname: Lee
authors.forename: Janos
authors.initials: J
authors.lastname: Zempleni
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D001710:Biotin / Q000378:metabolism*; D019735:Carbon-Carbon Ligases / Q000378:metabolism*; D019731:Carbon-Nitrogen Ligases / Q000378:metabolism*; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008214:Lymphocytes / Q000378:metabolism*; D008297:Male; D043586:Methylmalonyl-CoA Decarboxylase / Q000378:metabolism*; D008875:Middle Aged; D009751:Nutritional Requirements; D009752:Nutritional Status; D012333:RNA, Messenger / Q000378:metabolism; D012016:Reference Values; D014804:Vitamin B Deficiency / Q000378:metabolism*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D012333:RNA, Messenger; D001710:Biotin; D019731:Carbon-Nitrogen Ligases; C019791:biotin carboxylase; D019735:Carbon-Carbon Ligases; C021573:methylcrotonoyl-CoA carboxylase; D043586:Methylmalonyl-CoA Decarboxylase