Investigating lipid transition across brain capillary endothelium model
1 LIMES, University of Bonn
The brain is the most important organ in the body. Half of the brain tissue by dry weight is lipids. Lipids, especially the poly-unsaturated, are important for maintaining normal brain function. However, lipid transport into the brain is complex due to the presence of the Blood-Brain Barrier (BBB) and still poorly understood. One of the suggested routes of lipid uptake into the brain is through lysophosphatidylcholine (LPC) circulating in the blood. In this project, alkyne labelled LPCs together with shotgun lipidomics and fluorescent Thin-layer Chromatography were applied to investigate the importance of lipid transport across the brain endothelial capillary cell line, bEnd3. Cells were grown in a transwell setup to mimic the BBB and were used to study the role of LPC in lipid transport across the BBB. The alkyne labelled LPCs were taken up by the cells and secreted as different alkyne lipid species such as phosphatidylcholines, diacylglycerols and triacylglycerols. The secreted lipid species were preferentially acylated with arachidonic, docosahexaenoic and myristic fatty acids. Arachidonic and docosahexaenoic acids are poly-unsaturated fatty acids (PUFA) which proved important cognition, memory and brain development. These findings show the importance of LPCs as lipid carriers, especially PUFAs across the BBB.