Feeding enriched omega-3 fatty acid beef to rats increases omega-3 fatty acid content of heart and liver membranes and decreases serum vascular cell adhesion molecule-1 and cholesterol levels Denis M. Medeiros a, 4 , Meghan Hampton a , Kelly Kurtzer a , Mardi Parelman a , Enas Al-Tamimi a , James S. Drouillard b a Department of Human Nutrition, Kansas State University, Manhattan, KS 66506, USA b Department Animal Science and Industries, Kansas State University, Manhattan, KS 66506, USA Received 1 February 2007; revised 19 March 2007; accepted 10 April 2007 Abstract Dietary intake of the long-chain omega-3 fatty acids prevents the development of heart disease. In this study, we evaluated whether feeding beef from cattle fed an omega-3 fatty acid–enriched diet to rats had health benefits. Cattle raised on a 10% flaxseed diet have high amounts of a -linolenic acid in their muscle tissue when compared to cattle fed a control diet of corn. Twenty, weanling, Sprague- Dawley rats were fed one of two diets (n = 10 in each group), one diet containing fat from beef of cattle fed 10% flaxseed and the other beef from cattle fed a conventional corn ration. The diets contained 10% fat from the cooked beef using a modification of the American Institute of Nutrition diet formulated in 1976 diet for a 5-week period. There was a statistically significant increase in the amount of membrane docosahexaenoic acid in the livers of the rats on the diet of beef from cattle fed flaxseed and a statistically significant increase in the amount of membrane arachidonic acid in the hearts of the controls. There were also strong, positive trends for the increases in the amounts of membrane docosahexaenoic acid in the hearts and membrane linoleic acid in the livers of the rats on the diet of beef from cattle fed flaxseed when compared with controls. Serum cholesterol and vascular cell adhesion molecule-1 levels were decreased in rats fed the beef from cattle fed flaxseed. These findings suggest that agriculture practice of feeding a high omega-3 fatty acid diet to cattle can produce positive health benefits to the consumer. D 2007 Elsevier Inc. All rights reserved. Keywords: a-linolenic acid; Omega-3; EPA; DHA; Flaxseed; Rats 1. Introduction Dietary intake of long-chain omega-3 fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) protects against heart disease [1]. Heart health benefits are obtained by eating a diet high in long-chain omega-3 fatty acids results through the physiological properties of the biological compounds formed during either the cyclooxygenase or lipoxygenase pathways [2]. The positioning of the double bonds from the methyl end of the fatty acid chain causes the omega-3 and omega-6 fatty acids to be handled differently by the body. The end products of the cyclooxygenase pathway, thromboxanes, when made from omega-3 fatty acids, are less biologically active than thromboxanes formed from the omega-6 fatty acids [3,4]. The shorter-chain omega-3 fatty acid, a -linolenic acid (ALA), can be converted to EPA, and the EPA is converted to DHA [3-5]. However, controversy exists on whether an appreciable conversion occurs. If a large conversion of ALA 0271-5317/$ – see front matter D 2007 Elsevier Inc. All rights reserved. doi:10.1016/j.nutres.2007.04.003 4 Corresponding author. Tel.: +1 785 532 0150; fax: +1 785 532 3132. E-mail address: medeiros@ksu.edu (D.M. Medeiros). Nutrition Research 27 (2007) 295 – 299 www.elsevier.com/locate/nutres