Deuterium Oxide Labeling for Global Omics Relative Quantification: Application to Lipidomics

Area of Science:

• Lipidomics
• Quantitative Mass Spectrometry
• Metabolomics

Background:

• Accurate and robust relative quantification of lipids on a global scale is crucial for understanding cellular processes.
• Existing methods may have limitations in dynamic range, precision, or throughput for comprehensive lipidome analysis.

Purpose of the Study:

• To develop and validate a novel quantitative mass spectrometry method for global lipid relative quantification.
• To assess the precision, accuracy, and dynamic range of the developed method using cell-based experiments.
• To demonstrate the method's utility in analyzing biological lipidome changes under different conditions.

Main Methods:

• Development of Deuterium Oxide Labeling for Global Omics Relative Quantification (DOLGOReQ), a partial metabolic D2O labeling technique.
• Utilized in-house software for automated, high-throughput data analysis, filtering by mass isotopomers and deuterium labeling degree.
• Validation using mixed ratios of labeled and unlabeled HeLa cell lipids, assessing reproducibility, accuracy, and dynamic range.

Main Results:

• DOLGOReQ demonstrated high reproducibility and accuracy in quantifying equimolar lipid mixtures across replicates.
• An effective dynamic range of two orders of magnitude was established for relative quantification (10:1 to 1:10 ratios).
• Method performance was validated in both positive and negative ion modes and applied to measure lipidome changes under hypoxia.

Conclusions:

• DOLGOReQ provides a robust and precise platform for global relative lipid quantification using mass spectrometry.
• The method offers a significant dynamic range, suitable for analyzing complex biological samples.
• DOLGOReQ is effective for profiling relative changes in lipidomes, as demonstrated in a hypoxia stress model.