Stable isotope tracers and exercise physiology: past, present and future

Area of Science:

• Physiological research
• Human exercise physiology
• Metabolic regulation

Background:

• Stable isotope tracers have been used for over 80 years to study metabolism.
• Traditional substrate-specific tracers offer detailed insights but have limitations, including the need for intravenous infusions and short study durations.

Purpose of the Study:

• To explore the evolution of stable isotope tracer techniques in physiological research.
• To highlight the advantages of deuterium oxide (D2O) as a novel tracer for studying human metabolism and exercise physiology.

Main Methods:

• Comparison of traditional substrate-specific stable isotope tracers with deuterium oxide (D2O).
• D2O allows oral administration, enabling simultaneous monitoring of multiple substrate turnovers (proteins, lipids, glucose, DNA) over extended periods (hours to months).
• Application of D2O in 'real-world' human exercise physiology studies, integrating with omics technologies for dynamic proteomics and fluxomics.

Main Results:

• D2O overcomes limitations of traditional tracers, allowing flexible, long-term, and non-invasive studies.
• Enables simultaneous assessment of various metabolic pathways and tissue-specific substrate utilization.
• Facilitates the study of dynamic processes like exercise adaptation through integrated metabolomic and proteomic analyses.

Conclusions:

• Deuterium oxide represents a significant advancement in stable isotope tracer methodology.
• It offers unprecedented opportunities to investigate human metabolism and exercise physiology in diverse settings.
• Future applications integrating D2O with omics technologies hold great potential for advancing our understanding of biological systems.