Proteomic analysis of aorta of LDLR−/− mice given omega‐3 fatty acids reveals modulation of energy metabolism and oxidative stress pathway

Long chain omega 3 polyunsaturated fatty acids (LC-n-3PUFAs) exert potent anti-atherosclerotic action but the mechanisms of action at the vascular level remain unclear. The present study used a non-targeted nutrigenomic approach to investigate the modulations of the aortic proteome in atherosclerotic prone mice following DHA supplementation. LDLR-/- male mice received an atherogenic diet (20 weeks) in parallel with daily oral gavages with either oleic acid-rich oil (Control) or a mixture of oils providing 2% of energy as DHA. The overall protein expression was determined by a proteomic approach followed by bioinformatics analysis. In addition, protein oxidative modifications, namely 4-hydroxynonenal (4-HNE) protein adducts, were detected with a specific antibody followed by MS analysis of the identified spots. Nineteen differentially expressed proteins have been identified in the aorta of the DHA group. The top 5 canonical pathways analysis associated all proteins to metabolic pathways and showed that most of them were related to glucose or lipid metabolism. Up-regulation of superoxide dismutase also suggests an impact of DHA supplementation on vascular antioxidant defenses. The analysis of 4-HNE-protein adducts indicated that DHA supplementation did not enhance oxidative modification of proteins with 4-HNE. This study also identified some new proteins with 4-HNE adducts at the aortic level. In summary, DHA supplementation induces significant modifications of aorta proteome which point out the importance of metabolic changes occurring in the vascular tissue in the presence of LC-n-3PUFAs.