Choline and Ethanolamine Plasmalogens Prevent Lead-Induced Cytotoxicity and Lipid Oxidation in HepG2 Cells

Plasmalogens derived from dietary phospholipids are considered to be potential protectors against oxidation related disorders, while lead (Pb) is an environmental contaminant worldwide and is known to induce oxidative stress. However, the protective and antilipid oxidative effects of individual plasmalogen species against Pb damage have received little attention. In this study, six plasmalogen species (with either choline or ethanolamine as the headgroup and p16:0/18:1, p16:0/ 18:2, or p16:0/20:5 as the side chains) were evaluated in human hepatoma cells. Plasmalogen species showed a remarkable recovery in cell viability as well as elimination of reactive oxygen species and suppressed the accumulation of phosphatidylcholine hydroperoxides (from 63.6 +/- 1.8% to 80.3 +/- 2.9%) and phosphatidylethanolamine hydroperoxides (from 25.7 +/- 9.3% to 76.1 +/- 3.7%). Moreover, plasmalogens significantly upregulated the gene expression levels of a series of antioxidant enzymes that are regulated via the Nrf-2-dependent pathway. This study suggested that choline and ethanolamine plasmalogens could prevent Pb-induced cytotoxicity and lipid oxidation in HepG2 cells.