Lack of proinflammatory effects of free fatty acids on human umbilical cord vein endothelial cells and leukocytes

Aim. To determine whether the free fatty acids (FFAs), oleic, linoleic, and palmitic acid, found elevated before 20 weeks of pregnancy in those women who later develop preeclampsia, induced changes in expression of the vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), or E-selectin in cultured human umbilical cord vein endothelial cells (HUVEC), and integrin subunit CD11b, L-selectin or intracellular reactive oxygen species (ROS) in leukocytes. Methods. The VCAM-1, ICAM-1, and E-selectin expression were measured using ELISA in HUVEC after incubation with 100 mu mol of either oleic, linoleic, or palmitic acid for 6 hr and 24 hr. The co-reactivity with lipopolysaccharide (LPS), the amount of VCAM-1 mRNA in the cells, and soluble VCAM-1 in the incubation medium were measured as well. Leukocyte adhesion molecules and ROS were measured after incubation with 750 mu m of either of the FFAs in a whole blood model using flow cytometry. Results. No effects of the FFAs tested were found on the HUVEC or leukocyte adhesion molecule expression or intracellular ROS. The only exception to this was palmitic acid incubation, which significantly lowered the VCAM-1 expression in HUVEC after 24-hr incubation and also slowed the decay of VCAM-1 expressed after stimulation with LPS. Conclusions. The lack of significant proinflammatory changes of the FFAs tested might indicate that the elevated plasma levels of FFAs seen in preeclampsia most probably are products of the preeclamptic process rather than a causative factor.