Ascorbic acid-selenite interactions in humans studied with an oral dose of 74SeO3(2-).
The interaction between dietary ascorbic acid at extremes of ascorbic acid intake and selenium in young adult male humans was investigated with a stable-isotope approach using 74Se-selenite. Measurements were made of 74Se in plasma, urine, and feces with neutron-activation analysis after oral administration of 74SeO3(2-). Urine excretion and total body retention of isotope and the selenite-exchangeable metabolic pool (Se-EMP) were calculated. Limiting dietary ascorbic acid to about 20 mg/d appeared to reduce the time-related retention of absorbed selenite and the size of Se-EMP. Compared with a diet providing 1 g ascorbic acid/d the low ascorbic acid intake was associated with a lower fractional absorption of the isotope, a reduced retention of the label, and a smaller Se-EMP. These data and those previously obtained in subjects with more usual ascorbic acid intakes point to a possible important role for ascorbic acid in the maintenance of Se homeostasis.
Martin
R F
RF
Department of Applied Biological Sciences, Massachusetts Institute of Technology, Cambridge.
Young
V R
VR
Blumberg
J
J
Janghorbani
M
M
D000042:Absorption; D000328:Adult; D001205:Ascorbic Acid / Q000097:blood / Q000378:metabolism*; D001206:Ascorbic Acid Deficiency / Q000378:metabolism; D004032:Diet; D006801:Humans; D007554:Isotopes; D008297:Male; D020887:Selenious Acid; D012643:Selenium / Q000097:blood / Q000378:metabolism*; D018036:Selenium Compounds; D064588:Selenium Oxides
D007554:Isotopes; D018036:Selenium Compounds; D064588:Selenium Oxides; D020887:Selenious Acid; D012643:Selenium; D001205:Ascorbic Acid