Metabolomics: Quantitative Eicosanoids Profiling of Human Plasma and Serum: A New Data Processing Tool Using a Metabolic Map

Significance of the Topic

The profiling of eicosanoids in human blood is essential for biomarker identification and understanding disease mechanisms. By quantifying these bioactive lipids, researchers can elucidate inflammatory pathways and improve diagnostic and therapeutic strategies.

Objectives and Study Overview

This work aims to develop a comprehensive targeted analysis of eicosanoids in human plasma and serum using multiple reaction monitoring (MRM) and a novel data processing tool built on a metabolic map. The study compares quantitative differences across EDTA- and heparin-treated plasma and serum.

Methodology and Instrumentation

• Sample Preparation: 30 μL of plasma or serum was mixed with methanol (0.1% formic acid) and 18 isotope-labelled internal standards, followed by centrifugation and solid-phase extraction.
• Chromatography and Detection: An UHPLC system coupled to a fast triple-quadrupole mass spectrometer (LCMS-8060NX) with a Kinetex C8 column (2.1 × 150 mm, 2.6 μm) was used.
• Data Acquisition: Over 300 MRM transitions targeting 196 eicosanoids and related metabolites were monitored with polarity switching between negative and positive ion modes.
• Data Processing: Raw chromatograms were imported into the Garuda platform, mapped via LabSolutions Insight and VANTED, and visualized on a custom metabolic map.

Main Results and Discussion

• A total of 68 metabolites were detected: 67 in plasma (except TXB2) and 44 in serum.
• Free fatty acids (e.g., AA, EPA, DHA) were more abundant in serum, whereas downstream metabolites were elevated in plasma.
• TXB2 was present in serum only, indicating suppression of thrombogenic activity by anticoagulants.
• LOX-derived HETEs showed significantly higher levels in plasma, particularly in heparin-treated samples.
• CYP-derived metabolites (DHETs, 20-carboxy-AA) showed no significant plasma–serum differences.

Benefits and Practical Applications

This comprehensive MRM workflow combined with a tailored data processing tool allows high-throughput, quantitative mapping of eicosanoid profiles in clinical samples. It facilitates biomarker discovery, aids in the investigation of inflammatory disorders, and supports quality control in pharmaceutical research.

Future Trends and Potential Applications

• Expansion of target panels to include novel lipid mediators and oxidized lipids.
• Integration with other omics platforms for holistic pathway analysis.
• Automation of data processing for real-time clinical decision support.
• Application in personalized medicine to monitor patient-specific inflammatory signatures.

Conclusion

The developed approach successfully quantified key eicosanoids in human plasma and serum, and the metabolic map–based tool clearly highlighted differences across sample types. This methodology paves the way for advanced lipidomics studies in both research and clinical settings.

Instrumentation Used

• Shimadzu Nexera UHPLC system
• Shimadzu LCMS-8060NX triple quadrupole mass spectrometer
• Phenomenex Kinetex C8 column (2.1 × 150 mm, 2.6 μm)

References

• Yamada M. et al. J. Chromatography B, 995, 74–84 (2015).