Skeletal Muscle Lipidomics as a New Tool to Determine Altered Lipid Homeostasis in Fish Exposed to Urban and Industrial Wastewaters

This work applies ultrahigh performance
liquid chromatography coupled
with high-resolution mass spectrometry (UPLC-HRMS) to characterize
for the first time the lipidome of the skeletal muscle of two fish
species (Barbus meridionalis, Squalius laietanus) collected in a Mediterranean
River affected by urban and industrial wastewater outflows. The untargeted
analysis allowed a clear separation of the lipidome of fish from polluted
and reference sites; phosphatidylcholines (PCs), phosphatidylethanolamines
(PEs), and their lyso and ether-linked forms were among the distinctive
features. The targeted analysis consistently detected a decrease in
PC-plasmalogens (36:4, 36:6, 38:6) and highly unsaturated PCs (36:5,
36:6, 38:6, 40:6, 40:7) and an increase in plasmanyl-PCs (36:5, 38:5),
lyso-PCs (16:1, 18:1, 22:4) and cholesteryl esters (CEs) (16:0, 18:0,
20:4) in fish from polluted sites. These lipid profiles were indicative
of oxidative stress and dysregulation of cholesterol homeostasis in
fish from polluted sites. This methodology represents a promising
tool for the development of novel noninvasive diagnostic methods based
on muscle tissue biopsies to assess the effects of water pollution
in wildlife.