Voluntary Behavior and Training Conditions Modulate in vivo Extracellular Glucose and Lactate in the Mouse Primary...

Area of Science:

• Neuroscience
• Metabolism
• Behavioral Plasticity

Background:

• Learning new behaviors is metabolically demanding for the brain.
• Experience and practice reduce the metabolic cost of learned behaviors.
• Understanding brain energy metabolism during behavior is crucial.

Purpose of the Study:

• To investigate how novel and practiced motor behaviors affect brain glucose and lactate levels.
• To determine the role of behavior novelty and intensity in metabolic modulation.
• To explore the function of aerobic glycolysis in learning and neural plasticity.

Main Methods:

• Utilized biosensors in the primary motor cortex of mice.
• Measured extracellular glucose and lactate during novel and habituated wheel running.
• Assessed metabolic changes during varying intensities of motor behaviors.

Main Results:

• Motor behaviors increased extracellular lactate and decreased extracellular glucose in the primary motor cortex.
• These metabolic changes were modulated by behavior novelty, experience, and intensity.
• Increased extracellular lactate correlated strongly with behavioral novelty and difficulty.

Conclusions:

• Aerobic glycolysis may not primarily fuel neuronal activity but support the biosynthesis of new neural infrastructure during learning.
• Glucose-derived carbons are likely channeled into the pentose phosphate pathway for nucleotide synthesis.
• Metabolic adaptations in the brain are critical for acquiring and refining new behaviors.