The effects of saturated fatty acids on endothelial cells.

The present study reports on the effects of myristic(14:0), palmitic(16:0) and stearic(18:0) acids separately and combined with linoleic(18:2n-6), arachidonic(20:4n-6) and eicosapentaenoic(20:5n-3) acids on cultured human endothelial cell monolayers(ECM). The cell viability determined by trypan blue exclusion study, the release of lactate dehydrogenase(LDH) and 6-keto-PGF1 alpha into the medium from ECM incubated with albumin bound fatty acids(FA) were measured. The cell viability was reduced and the release of LDH from ECM was enhanced by 18:0(0.2mM, ratio 1, 2 and 4) and 16:0(0.4mM, ratio 2), but not by 14:0, or the unsaturated FA. The reduced cell viability induced by 18:0 was completely inhibited by polyunsaturated FA, 18:2n-6, 20:4n-6 and 20:5n-3. The release of 6-keto-PGF1 alpha was increased by 18:0, but not by 14:0 and 16:0. All three saturated FA potentiated 6-keto-PGF1 alpha production induced by 20:4n-6. Combined with 18:2n-6 or 20:5n-3, they also stimulated 6-keto-PGF1 alpha production. This study indicates that the three main dietary SFA, 18:0, 16:0 and 14:0 do not have the same effects on ECM. The damaging effect on endothelial cells induced by 18:0 and 16:0 may be of significance for the thrombogenic effects related to these saturated fatty acids.