Oxylipins and free fatty acids in parenteral lipid emulsions currently used in preterm infant care: an in vitro study

Abstract

Lipid emulsions used to support nutrition in preterm infants contain long-chain polyunsaturated fatty acids (LCPUFAs) as a source of essential fatty acids; these LCPUFAs and their parent polyunsaturated fatty acid (PUFA) can be oxidized by a variety of mechanisms to bioactive molecules called oxylipins, which are signaling molecules that initiate and/or resolve inflammation. The aim of this study was to explore levels of free LCPUFA and their related oxylipins in 3 commercially available lipid emulsions (Intralipid, SMOFlipid, and ClinOleic) using ultra high-performance liquid chromatography mass spectroscopy. Free LCPUFA were detected in all lipid emulsions tested. Seven, 8, and 9 different oxylipin compounds were detected in the 3 emulsions, respectively. The oxylipins detected were mainly derived from omega-6 PUFAs; these included 13-hydroxyoctadecadienoic acid from linoleic acid and 5-hydroxyeicosatetraenoic acid derived from arachidonic acid. It may be clinically important to know that oxylipins exist in lipid emulsions and to evaluate their potential effects on preterm infants.