Accumulation of DHA in HepG2 cell membranes is elevated following supplementation with fatty acids found in dairy fat

Special issue: Dairy Science World Series Conference 2005 proceedings 'Functional Dairy Foods' Adelaide, July 27-28, 2005. Short presentationHealth authorities have recognised the importance of n-3 long chain polyunsaturated fatty acids (LCPUFA) in maintaining health and it is generally accepted that we need to increase our dietary intake of these fatty acids, particularly eicosapentaenoic acid (20:5n-3, EPA) and docosahexaenoic acid (22:6n-3, DHA). Common practice has been to increase our intake of fish, consume fish oil supplements or increase our intake of n-3 enriched foods. These practices rely heavily on a declining global fish supply. Alternative ways to increase our n-3 LCPUFA status are, therefore, imperative. The fatty acids found in dairy fat may provide an alternate source to increase our n-3 LCPUFA status. We examined the accumulation of EPA and DHA in HepG2 cells supplemented with a-linolenic acid (18:3n-3, ALA), EPA and docosapentaenoic acid (22:5n-3, DPA). There was a dose-dependent increase in the level of ALA, EPA and DPA in HepG2 cell phospholipids following supplementation with these respective fatty acids. The accumulation of DHA, the long chain n-3 metabolite of fatty acid synthesis, was significantly higher in cells supplemented with EPA and DPA compared to those supplemented with ALA. Dairy fats uniquely contain greater amounts of EPA and DPA than ALA and no DHA. This study suggests that the fatty acids found in dairy fats have the capacity to elevate the level of DHA in cell membranes.R. Portolesi, B. C. Powell and R. A. Gibso