Zebrafish larvae as a model system for systematic characterization of drugs and genes in dyslipidemia and atherosclerosis

Hundreds of loci have been robustly associated with circulating lipids, atherosclerosis and coronary artery disease; but for most loci the causal genes and mechanisms remain uncharacterized. We developed a semi-automated experimental pipeline for systematic, quantitative, large-scale characterization of mechanisms, drugs and genes associated with dyslipidemia and atherosclerosis in a zebrafish model system. We validated our pipeline using a dietary (n>2000), drug treatment (n>1000), and genetic intervention (n=384), and used it to characterize four candidate genes in a GWAS-identified pleiotropic locus on chr 19p13.11 (n=384). Our results show that five days of overfeeding and cholesterol supplementation had independent pro-atherogenic effects, which could be diminished by concomitant treatment with atorvastatin and ezetimibe. CRISPR-Cas9-induced mutations in orthologues of proof-of-concept genes resulted in higher LDL cholesterol levels ( apoea ), more vascular inflammation ( apobb.1 ), and more early-stage atherosclerosis ( ldlra ). Finally, our pipeline helped identify putative causal genes for circulating lipids and early-stage atherosclerosis ( LPAR2 ), as well as for diabetes ( GATAD2A ). In summary, our pipeline facilitates systematic, in vivo characterization of drugs and candidate genes to increase our understanding of disease etiology, and can likely help identify novel targets for therapeutic intervention.