Endothelial Barrier Disruption by Lipid Emulsions Containing a High Amount of N3 Fatty Acids (Omegaven) but Not N6 Fatty Acids (Intralipid)

Lipid emulsions are crucial for life-saving total parenteral nutrition (TPN). Their composition provides a high amount of essential fatty acids and calories for millions of patients with serious diseases. Nevertheless, several TPN-mediated side-effects have been reported in over 90% of patients. This project aimed to investigate the effect of a high amount of ω3 fatty acids (Omegaven^®) emulsion vs. a high amount of ω6 fatty acids (Intralipid^®) emulsions on the endothelial barrier function. EA.hy926 cell line was cultured and incubated with 0.01, 0.1, and 1 mM lipid emulsions. The influence of these lipid emulsions on the barrier function was assessed using ECIS technology, immunofluorescent microscopy, viability measurements by flow cytometry, multiplex cytokines analysis, and qRT-PCR. BODIPY staining confirmed the uptake of fatty acids by endothelial cells. ECIS measurements demonstrated that a high concentration of Omegaven^® prevents barrier formation and impairs the barrier function by inducing cell detachment. Moreover, the expression of VE-cadherin and F-actin formation showed a reorganization of the cell structure within 2 h of 1 mM Omegaven^® addition. Interestingly, the study's findings contradict previous studies and revealed that Omegaven^® at high concentration, but not Intralipid, induces cell detachments, impairing endothelial cells' barrier function. In summary, our studies shed new light on the effect of lipid emulsions on the endothelium.