Serum selenium predicts levels of F2-isoprostanes and prostaglandin F2α in a 27 year follow-up study of Swedish men

Low concentrations of selenium (Se) predict mortality and cardiovascular diseases in some populations. The effect of Se on in vivo indicators of oxidative stress and inflammation, two important features of atherosclerosis, in human populations is largely unexplored. This study investigated the longitudinal association between serum selenium (s-Se) and a golden standard indicator of oxidative stress in vivo (8-iso-prostaglandin F-2 alpha, a major F2-isoprostane), an indicator of cyclooxygenase (COX)-mediated inflammation ( prostaglandin F-2 alpha), high sensitive C-reactive protein (hsCRP), interleukin- 6 (IL- 6) and serum amyloid A protein (SAA) in a follow-up study of 27 years. The s-Se was measured in 615 Swedish men at 50 years of age in a health investigation. The status of oxidative stress and inflammation was evaluated in a re- investigation 27 years later by quantification of urinary 8-iso-PGF(2 alpha) and 15-keto-dihydro-PGF(2 alpha) (a major metabolite of PGF(2 alpha)) and serum hsCRP, SAA and IL-6. Men in the highest quartile of s-Se at age 50 had decreased levels of 8-iso-PGF(2 alpha) compared to all lower quartiles (P < 0.01-0.05),and decreased levels of PGF(2 alpha) compared to all lower quartiles (P=0.001-0.05), at follow-up. These associations were independent of BMI, diabetes, hyperlipidemia, hypertension, smoking, alpha-tocopherol and beta-carotene at baseline. The s-Se was not associated with hsCRP, SAA or IL- 6 at follow-up. In conclusion, high concentrations of s-Se predict reduced levels of oxidative stress and subclinical COX-mediated ( but not cytokine-mediated) inflammation in a male population. The associations between Se, oxidative stress and inflammation, respectively, might be related to the proposed cardiovascular protective property of Se.