Lipidomic analysis of plasma in patients with lacunar infarction using normal-phase/reversed-phase two-dimensional liquid chromatography–quadrupole time-of-flight mass spectrometry

Abstract

Stroke is a major cause of mortality and long-term disability worldwide. The study of biomarkers and pathogenesis is vital for early diagnosis and treatment of stroke. In the present study, a continuous-flow normal-phase/reversed-phase two-dimensional liquid chromatography-quadrupole time-of-flight mass spectrometry (NP/RP 2D LC-QToF/MS) method was employed to measure lipid species in human plasma, including healthy controls and lacunar infarction (LI) patients. As a result, 13 lipid species were demonstrated with significant difference between the two groups, and a "plasma biomarker model" including glucosylceramide (38:2), phosphatidylethanolamine (35:2), free fatty acid (16:1), and triacylglycerol (56:5) was finally established. This model was evaluated as an effective tool in that area under the receiver operating characteristic curve reached 1.000 in the discovery set and 0.947 in the validation set for diagnosing LI patients from healthy controls. Besides, the sensitivity and specificity of disease diagnosis in validation set were 93.3% and 96.6% at the best cutoff value, respectively. This study demonstrates the promising potential of NP/RP 2D LC-QToF/MS-based lipidomics approach in finding bio-markers for disease diagnosis and providing special insights into the metabolism of stroke induced by small vessel disease. Graphical abstract Flow-chart of the plasma biomarker model establishment through biomarker screening and validation.

Metabolome Changes in Cerebral Ischemia

“…Other pathophysiological and metabolic changes have also been suggested in the context of cerebral ischemia [40,65,76,[96][97][98][99][100][101]. Increased levels of formate and glycolate and decreased levels of dimethylamine, glycine, hippurate, and methanol have been suggested to be related with hyperhomocysteinemia [40].…”

“…Elevated levels of C5:1 (tiglylcarnitine) have been suggested to relate to platelet dysfunction by peroxisome proliferator-activated receptor α (PPARα), and elevated levels of alanine are suggested to be related to neuronal autophagy by increasing carnosine content in blood samples of cerebral ischemia patients [99]. Altered levels of phosphorus-containing compounds, ceramides, amino acids, fatty acids, carbohydrates, cholines, polyamines, and membrane lipids have been suggested as biomarkers for cerebral ischemia, but the lack of detailed mechanistic explanation for these changes represents a limitation [65,76,85,96,98,100,101]. Moreover, there are discrepancies in reported patterns of analyzed metabolite levels among studies.…”

Free fatty acid profiling in marine algae extract by LC‐MS/MS and isolation as well as quantification of the ω‐3 fatty acid hexadeca‐4,7,10,13‐tetraenoic acid

“…Since unmodified fatty acids show no or only little fragmentation in MS/MS experiments, a high mass resolution is crucial for lipid identification based on precursor mass accuracy. Increasingly, fatty acids are detected next to other lipid species in an untargeted manner during lipidomics analysis . Unfortunately, free fatty acids are only present in relative low concentrations next to high abundant lipid species like phospholipids and glycerols.…”

Sphingolipids Profiling of Plasma in Patients with Diabetes Mellitus Associated with Atherosclerosis by a Novel Normal-Phase UPLC-QToF MS Method

“…The details of this identification method were described in our previous works [13,[21][22][23][24]. In the end, 12 sphingolipids were identified by high-accuracy mass values and retention time, including one SPAH, two Cers, five GluCs, and four LacCs.…”