Abstract 3244: Supplementation with selenium-enriched yeast but not selenomethionine reduces oxidative stress in healthy men in a randomized clinical trial

Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Epidemiological and laboratory studies indicate that dietary selenium is protective against prostate cancer. Results from clinical trials suggest that selenium-enriched yeast (SY) but not selenomethionine (SeMet) may be effective at reducing prostate cancer risk. Our objectives were to directly compare for the first time the effects of SeMet and SY on prostate cancer relevant biomarkers in men. We performed a randomized double blind, placebo-controlled trial of SY (200 or 285 μg/day) and SeMet (200 μg/day) administered for 9 months in 69 healthy adult males. Biomarkers including blood selenium, glucose, PSA and glutathione (GSH) and urine 8-hydroxy-2’-deoxyguanosine (8-OHdG) and 8-iso-prostaglandin-F2α (8-iso-PGF2α) were measured at baseline and various times thereafter. Compliance was high in all groups (>95%). Plasma selenium levels were increased 93%, 54%, and 86% after 9 months in the SeMet and low and high dose SY groups, respectively, and returned to baseline levels after a 3 month washout (P<0.05). Urinary biomarkers of oxidative stress, 8-OHdG and 8-iso-PGF2α, were decreased 34% and 28%, respectively, after 9 months in the high dose SY group (P<0.05). Decreases in oxidative stress biomarkers were greatest in individuals with low baseline plasma levels of selenium (<127 ng/ml). No changes in serum PSA or blood glucose and GSH were observed. We showed for the first time reductions in biomarkers of oxidative stress following supplementation with SY but not SeMet in healthy men. These findings suggest that selenium-containing compounds other than SeMet may be responsible for the decrease in oxidative stress and possibly cancer risk. This work was supported a National Cancer Institute grant (R01CA127729). Citation Format: Matt G. Kaag, John P. Richie, Arun Das, Ana Calcagnotto, Raghu Sinha, Wanda Neidig, Jiangang Liao, Eugene J. Lengreich, Arthur Berg, Terryl J. Hartman, Amy Ciccarella, Aaron Baker, Telih Boyiri, Susan Goodin, Robert S. DiPaola, Karam El-Bayoumy. Supplementation with selenium-enriched yeast but not selenomethionine reduces oxidative stress in healthy men in a randomized clinical trial. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3244. doi:10.1158/1538-7445.AM2014-3244