Diet high in omega‐3 fatty acids alters the fatty acid composition of bioactive lipids: a lipidomic approach

Abstract

Omega (n)‐3polyunsaturated fatty acids (PUFA) are converted to bioactive lipid components that are important mediators in metabolic and physiological pathways; however, which bioactive compounds are metabolically active, and their mechanisms of action are still not clear. We investigated using lipidomics techniques, the effects of diets high in n‐3 PUFA on the fatty acid composition of various bioactive lipids in plasma and liver. Female C57BL/6 mice were fed semi‐purified diets (20% w/w fat) containing varying amounts of n‐3 PUFA before mating, during pregnancy, and until weaning. Male offspring (n=6) were continued on their mothers’ diets for four months. Hepatic and plasma lipids were extracted and tandem electrospray ionization mass spectrometry methods were used to measure the fatty acid compositions. There was a higher concentration of eicosapentaenoic acid containing phosphatidylcholine (PC) and lysophosphatidylcholine (LPC) (p < 0.05) in the high n‐3 PUFA group compared to the low n‐3 PUFA group. Plasma and liver from the high n‐3 PUFA group also had higher concentration of free n‐3 PUFA (p < 0.05). Our findings reveal for the first time that diet high in n‐3 PUFA caused enrichment of n‐3 PUFA in PC, LPC and free fatty acids in the offspring. PC and LPC are important bioactive lipids, thus altering their fatty acyl composition will likely have important metabolic and physiological roles.Supported by NSERC