Abstract:
The identification and quantitation of all lipids in complex biological tissues is the
first step towards the understanding how lipids function in a biological system and
the elucidation of the mechanism of lipid-related diseases including obesity,
atherosclerosis, cancer, cardiovascular diseases, etc. Our optimized nontargeted
method using hydrophilic interaction liquid chromatography (HILIC) coupled to
electrospray ionization mass spectrometry (ESI-MS) was used for the
characterization of the lipidome, mainly glycerophospholipids and sphingolipids
in porcine brain, heart, kidney, liver, lung, spinal cord, spleen and stomach.
Individual lipid classes are quantified based on the peak integration of individual
lipid classes separated in the HILIC mode multiplied by their response factors and
correlated by sphingosylethanolamine (d17:1/12:0) as a single internal standard.
Subsequently, relative abundances of deprotonated molecules [M-H]– in negativeion
ESI mass spectra are used for determination of lipid species concentration
inside individual classes. The approach using [M-H]– ions enables to obtain detailed information about phosphatidylethanolamines and their different forms
of fatty acyl linkage on the glycerol skeleton (plasmalogens and ether analogs),
phosphatidylinositols and hexosylceramides in studied organs. Our results
provide important knowledge about lipid representations in vital porcine organs
and can be applied for future metabolic studies on human to investigate serious
lipid-related human disorders.
