Differential responses to selenomethionine supplementation by sex and genotype in healthy adults

Br J Nutr. 2012 May;107(10):1514-25. doi: 10.1017/S0007114511004715. Epub 2011 Sep 22.

Abstract

A year-long intervention trial was conducted to characterise the responses of multiple biomarkers of Se status in healthy American adults to supplemental selenomethionine (SeMet) and to identify factors affecting those responses. A total of 261 men and women were randomised to four doses of Se (0, 50, 100 or 200 μg/d as L-SeMet) for 12 months. Responses of several biomarkers of Se status (plasma Se, serum selenoprotein P (SEPP1), plasma glutathione peroxidase activity (GPX3), buccal cell Se, urinary Se) were determined relative to genotype of four selenoproteins (GPX1, GPX3, SEPP1, selenoprotein 15), dietary Se intake and parameters of single-carbon metabolism. Results showed that supplemental SeMet did not affect GPX3 activity or SEPP1 concentration, but produced significant, dose-dependent increases in the Se contents of plasma, urine and buccal cells, each of which plateaued by 9-12 months and was linearly related to effective Se dose (μg/d per kg0·75). The increase in urinary Se excretion was greater for women than men, and for individuals of the GPX1 679 T/T genotype than for those of the GPX1 679 C/C genotype. It is concluded that the most responsive Se-biomarkers in this non-deficient cohort were those related to body Se pools: plasma, buccal cell and urinary Se concentrations. Changes in plasma Se resulted from increases in its non-specific component and were affected by both sex and GPX1 genotype. In a cohort of relatively high Se status, the Se intake (as SeMet) required to support plasma Se concentration at a target level (Se(pl-target)) is: Se(in) = [(Se(pl - target) - Se(pl))/(18.2ng d kg⁰.⁷⁵/ml per mu g)] .

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Aged
  • Biomarkers / metabolism
  • Carbon / metabolism
  • Dietary Supplements*
  • Dose-Response Relationship, Drug
  • Female
  • Genotype*
  • Glutathione Peroxidase / genetics*
  • Glutathione Peroxidase / metabolism
  • Humans
  • Male
  • Middle Aged
  • Mouth / cytology
  • Mouth / metabolism
  • Mouth Mucosa / cytology
  • Mouth Mucosa / metabolism
  • Selenium / blood
  • Selenium / metabolism*
  • Selenium / urine
  • Selenomethionine / pharmacokinetics*
  • Selenoprotein P / metabolism
  • Selenoproteins / genetics*
  • Selenoproteins / metabolism
  • Sex Factors*

Substances

  • Biomarkers
  • Selenoprotein P
  • Selenoproteins
  • Carbon
  • Selenomethionine
  • GPX3 protein, human
  • glutathione peroxidase GPX1
  • Glutathione Peroxidase
  • Selenium