Selenium supplementation prevents the increase in atherogenic electronegative LDL (LDL minus) in the postprandial phase Fausta Natella a, *, Michela Fidale a , Franco Tubaro b , Fulvio Ursini c , Cristina Scaccini a a Free Radical Research Group, National Research Institute for Food and Nutrition, Via Ardeatina 546, 00178 Roma, Italy b Department of Chemical Sciences and Technology, University of Udine, Udine, Italy c Department of Biological Chemistry, University of Padova, Padova, Italy Received 3 February 2006; received in revised form 9 May 2006; accepted 10 May 2006 KEYWORDS LDL minus; Postprandial oxidative stress; Selenium; Human Abstract Evidence is accumulating that postprandial phenomena play a role in athero- genesis. Dietary lipid hydroperoxides that escape from the gastrointestinal barrier can be incorporated into plasma lipoproteins, leading to a modified form of LDL (LDL minus). The present human study was designed to investigate the effect of selenium sup- plementation on the formation of LDL minus in the postprandial phase. Fourteen healthy subjects ate the same test meal, high in lipid hydroperoxides, at baseline and after 10-day selenium supplementation (110 mg/day). Plasma selenium, LDL mi- nus, LDL resistance to oxidative modification, plasma antioxidants (ascorbic acid, GSH and GPx activity) and MDA were measured in preprandial (time 0) and postpran- dial (3 h) phases. Supplementation did not induce changes in the concentration of selenium in fasting plasma, but, at the same time, it induced a significant decrease in preprandial plasma GPx activity and inhibited the meal-induced increase in GPx activity. Selenium supplementation fully prevented the meal-induced increase in both LDL minus level and LDL susceptibility to oxidation. This study demonstrated the efficacy of selenium in preventing postprandial oxida- tive stress. The results, obtained on subjects adequately supplied with selenium, suggest that a non-limiting selenium availability counteracts the postprandial forma- tion of the atherogenic form of LDL and provide a rationale for the epidemiological evidence of the inverse correlation between selenium intake and the incidence of chronic and degenerative diseases. ª 2006 Elsevier B.V. All rights reserved. * Corresponding author. Tel.: þ39 06 51494481; fax: þ39 06 51494550. E-mail address: natella@inran.it (F. Natella). 0939-4753/$ - see front matter ª 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.numecd.2006.05.002 Nutrition, Metabolism & Cardiovascular Diseases (2007) 17, 649e656 www.elsevier.com/locate/nmcd