Partially ¹³C-labeled mouse tissue as reference for LC-MS based untargeted metabolomics

Area of Science:

• Metabolomics
• Biochemistry
• Analytical Chemistry

Background:

• Stable isotope-labeled standards are crucial for metabolite quantification in untargeted metabolomics.
• Ideal standards mirror the labeled metabolites present in the sample for comprehensive analysis.

Purpose of the Study:

• To evaluate partially 13C-labeled mouse material as an internal standard for relative metabolite quantification in untargeted metabolomics.
• To assess the accuracy and precision of this method for analyzing mouse and human samples.

Main Methods:

• Mice were fed a 13C-labeled diet for 14 days, resulting in partially labeled amino acids (6-75% enrichment).
• MetExtract II software was employed for automated detection of native and labeled metabolite peaks.
• Partially 13C-labeled mouse plasma was used with a correction factor in a dilution series for quantification via liquid chromatography-mass spectrometry.

Main Results:

• Partially 13C-labeled mouse plasma enabled accurate relative quantification of human plasma amino acids.
• The coefficient of variation for relative quantification decreased from 27% (without standard) to 10% (with standard).

Conclusions:

• Partially 13C-labeled mouse material is a viable and effective internal standard for untargeted metabolomics.
• This approach enhances the accuracy of relative metabolite quantification in human samples, with broad applicability expected.