title: In vivo biotin supplementation at a pharmacologic dose decreases proliferation rates of human peripheral blood mononuclear cells and cytokine release.
abstract: Theoretically, vitamin supplements may either enhance or reduce protein synthesis and proliferation in peripheral blood mononuclear cells (PBMC). In the present study, we determined whether administration of a pharmacologic dose of biotin affects proliferation rates of PBMC and cytokine release. Healthy adults (n = 5) ingested 3.1 micromol biotin/d for 14 d; blood and urine were collected pre- and postsupplementation. PBMC were isolated by density gradient and incubated with the mitogen concanavalin A for up to 3 d. At timed intervals during mitogen stimulation, we measured the following: 1) cellular uptake of [(3)H]thymidine to determine proliferation rates; 2) concentrations of various cytokines released into the medium; and 3) the percentages of PBMC subsets as judged by CD surface markers. Biotin supplementation caused a significant decrease of PBMC proliferation. At 2 d after mitogen stimulation, [(3)H]thymidine uptake by postsupplementation PBMC was 66 +/- 21% of the uptake by presupplementation PBMC (P < 0.05). Similarly, concentrations of interleukin-1beta (2 d after mitogen) and interleukin-2 (1 d after mitogen) in media from postsupplementation PBMC were 65 +/- 28% and 44 +/- 23%, respectively, of those for presupplementation PBMC (P < 0.01). Percentages of PBMC subsets were not affected by 14 d of biotin supplementation. Overall, this study provides evidence that administration of pharmacologic doses of biotin for 14 d decreases PBMC proliferation and synthesis of interleukin-1beta and interleukin-2.
authors.affiliation: Department of Nutritional Science and Dietetics, University of Nebraska at Lincoln, Lincoln, NE 68583, USA.
authors.forename: J
authors.initials: J
authors.lastname: Zempleni
authors.forename: R M
authors.initials: RM
authors.lastname: Helm
authors.forename: D M
authors.initials: DM
authors.lastname: Mock
mesh_terms: D000284:Administration, Oral; D000328:Adult; D001710:Biotin / Q000097:blood / Q000494:pharmacology* / Q000652:urine; D016207:Cytokines / Q000378:metabolism; D005260:Female; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D013936:Thymidine / Q000493:pharmacokinetics
chemical_list: D016207:Cytokines; D001710:Biotin; D013936:Thymidine