Effects of dietary fatty acids and vitamin E levels in HL-60 cell proliferation

Background Fatty acids have shown to be both modulators and messengers of s ignals triggered at the level of cell membranes. There is, however, controv ersy about the role of fatty acids in cell proliferation kinetics, and it i s still unknown whether cell proliferation can be regulated by fatty acid d ietary intake in humans. Our objective was to investigate whether feasible changes in the human dietary food intake that induce significant changes in lipids, fatty acids and the oxidative state were able to influence prolife ration kinetics of the leukaemia cell line HL-60. Materials and methods Healthy men and women were subjected to four consecut ive dietary periods with increasing degree of unsaturation: saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), n-6 polyunsaturated fat ty acids (n-6 PUFAs), n-3 polyunsaturated fatty acids (n-3 PUFAs). Plasma l ipids and oxidation parameters were controlled during each period. Serum fr om each subject in the four dietary periods was incubated for 3 days with t he leukaemia cell line, HL-60 (250 x 10(3) cell mL(-1)), to study cell prol iferation. Results In men, an n-3 polyunsaturated fatty acid-enriched diet showed a si gnificant inhibition of DNA duplication with respect to a saturated-enriche d diet, but the effect is not sufficient in blocking cell proliferation. Ho wever, as expected, the in vitro addition of fatty acids to HL-60 cells sig nificantly halted proliferation. In addition, the HL-60 growth ratio was sh own to be inversely correlated with plasma vitamin E (P = 0.0004) and oleic acid in phospholipids (P = 0.01) in plasma of the individuals in the dieta ry intervention study. Conclusions Our results demonstrate that changes in serum fatty acid compos ition obtained with dietary changes, without extreme variations of the regu lar diets of a free-living population, cannot block HL-60 cell proliferatio n.