Abstract 15628: Endothelial Cell RNAseq in Hypercholesterolemic Zebrafish Reveals Early Dynamic Changes in Neuromast-Enriched Genes

IntroductionThe cellular and molecular phenotypes of atherosclerosis during development are largely unknown. Zebrafish has emerged as an appealing model to understand endothelial dysfunction during early atherogenesis, owing to their translucency enabling real-time imaging and large breeding capacity for high throughput screening. Furthermore, zebrafish share many of the same developmental pathways as humans, allowing the study of early vascular processes in a fully integrated vertebrate system.MethodsWe fed larval zebrafish regular or high cholesterol diet (4%) for one week from 5 days post fertilization and isolated endothelial enriched compartments by fluorescent activated cell sorting using the endothelial cell marker FLK:GFP. We performed transcriptome profiling of sorted endothelial cells. We also examined endothelial morphological changes in high cholesterol-fed larval fish with live imaging.ResultsIn addition to the anticipated findings in lipid metabolism, we found an unexpected 4-10 fold enrichment of 16 neuromast-related genes in the endothelial-enriched compared to endothelial-depleted cell fractions. The expression of these neuromast-related genes is significantly down-regulated 3.1 +/- 0.5 fold by high cholesterol diet when compared with a control diet. These changes are not observed in unsorted samples or in controls. In association with these defects, there were highly reproducible abnormalities of vascular patterning with significantly increased branching indices estimated using a wide range of endpoints with Image J (p