Quantitative lipidome analysis of serum from mouse exposed to microplastic using deuterium oxide labeling

Abstract

Microplastics are small (typically less than 5 mm) pieces of plastic fragments and have become global environmental and health concerns due to pollution of the aquatic system including oceans, rivers, and lakes as well as air and soil. Most studies on the health risks caused by microplastic exposure have been conducted on marine organisms with high concentrations of microplastics. To study the in vivo effects of low concentrations of microplastics on mammal, untargeted lipidomic analysis was performed with a mouse model based on Deuterium Oxide (D2O) Labeling for Global Omics Relative Quantification (DOLGOReQ) technique that we have recently developed. For experimental group, ICR mice were administrated with microplastics in drinking water for 5 weeks. The plastic concentration was set to consume 386.82 ng of polyethylene (PE) and polystyrene (PS) per day. Four and five replicates of mice were exposed to PS and PE, respectively. The concentration of plastic in drinking water was changed weekly based on the mouse weight. For the control groups, four replicates of ICR mouse were fed by either normal drinking water or 5% D2O enriched drinking water. After 5 weeks, serum samples were collected from both experimental and control groups. Lipids were extracted from mouse serum using Folch method. Lipid extracts were analyzed by high-performance liquid chromatography-mass spectrometry. Finally, relative quantification of lipidome between experimental and control groups was performed by DOLGOReQ. A total of 212, 176, and 301 lipids were identified from control, PE, and PS groups, respectively. Among them, 136 lipids were commonly identified. In the relative quantitative analyses, 2 sphingomyelins in PE exposed group and 2 glycerophosphoethanolamines in PS exposed group showed significant changes compared with control group.