Measuring Cellular Adenine Nucleotides by Liquid Chromatography-Coupled Mass Spectrometry.

Area of Science:

• Cellular metabolism
• Biochemistry
• Analytical chemistry

Background:

• Adenine nucleotides (AXPs) like AMP, ADP, and ATP are crucial for cellular energy transfer and signaling.
• Existing methods (HPLC/CE) struggle to accurately measure low AMP concentrations, often requiring extrapolation.
• Accurate AXP quantification is vital for understanding metabolic regulation, including AMPK pathways.

Purpose of the Study:

• To develop and detail a protocol for accurate measurement of all adenine nucleotides (AXPs) in cellular samples.
• To overcome the sensitivity limitations of traditional HPLC/CE methods for AMP quantification.
• To provide a robust LC/MS method applicable to diverse biological fields, particularly AMPK-dependent metabolism.

Main Methods:

• Liquid chromatography-coupled mass spectrometry (LC/MS) was employed for AXP quantification.
• A detailed protocol was established for sample preparation and analysis.
• The method was validated for accuracy and sensitivity in measuring cellular AXPs.

Main Results:

• The developed LC/MS protocol accurately quantifies cellular concentrations of AMP, ADP, and ATP.
• This method provides direct measurement of AMP, eliminating the need for equilibrium assumptions.
• The protocol demonstrates high sensitivity and applicability across various cell types and biological samples.

Conclusions:

• LC/MS offers a superior method for comprehensive AXP analysis in biological research.
• Accurate measurement of AXPs, especially AMP, enhances understanding of cellular energy status and metabolic control.
• This protocol facilitates advancements in fields reliant on precise metabolic profiling, such as AMPK-mediated regulation.