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Published on: November 21, 2016
Lactate: link between glycolytic and oxidative metabolism
1Department of Integrative Biology, University of California, Berkeley, California 94720-3140, USA. gbrooks@berkeley.edu
Sports Medicine (Auckland, N.Z.)
|May 1, 2007
Summary
Lactate is continuously produced and used in aerobic conditions, not just during oxygen deprivation. Understanding the lactate shuttle is crucial for energy metabolism, especially in endurance sports like marathon running.
Area of Science:
- Exercise Physiology
- Cellular Metabolism
- Biochemistry
Background:
- Lactate was historically considered a byproduct of anaerobic metabolism in muscle.
- Emerging evidence shows continuous lactate production and utilization even under aerobic conditions.
- The 'lactate shuttle' concept highlights its roles beyond a simple metabolic waste product.
Purpose of the Study:
- To elucidate the continuous formation and utilization of lactate under aerobic conditions.
- To describe the 'cell-cell' and 'intracellular lactate shuttle' mechanisms.
- To explore the implications of lactate shuttling in cellular energy transduction and signaling.
Main Methods:
- Review of existing literature on lactate metabolism and transport.
- Analysis of lactate flux in various tissues, including skeletal muscle and brain.
- Examination of lactate's role in oxidative and gluconeogenic pathways.
Main Results:
- Lactate is produced and consumed continuously in fully aerobic states.
- Lactate shuttles facilitate substrate delivery for oxidation and gluconeogenesis.
- Examples include inter-fiber, muscle-heart, and tissue-specific shuttles, including in the brain.
Conclusions:
- Lactate shuttling integrates glycolysis, glycogenolysis, and oxidative metabolism.
- Oxidation is the primary disposal route for lactate, especially during exercise (70-75%).
- Further understanding and application of lactate shuttle principles are needed, particularly in sports science.
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