Running-induced neurogenesis reduces CA1 perineuronal net density without substantial temporal delay

Area of Science:

• Neuroscience
• Exercise Physiology

Background:

• Aerobic exercise influences brain function, particularly the hippocampus.
• Previous research shows exercise increases adult neurogenesis in the dentate gyrus and decreases perineuronal nets in CA1.
• The temporal relationship between these effects has not been precisely determined due to long experimental durations.

Purpose of the Study:

• To investigate the precise temporal dynamics of running-induced neurogenesis and perineuronal net density changes in the hippocampus.
• To determine the minimum time frame required for observable effects of aerobic exercise on these hippocampal markers.

Main Methods:

• Male and female mice were given access to running wheels for 0, 1, 2, or 4 weeks.
• Hippocampal neurogenesis rates and CA1 perineuronal net density were quantified.

Main Results:

• A significant delay of two weeks was observed before an increase in neurogenesis occurred.
• This two-week delay also preceded the decrease in CA1 perineuronal net density.
• Neurogenesis and perineuronal net density changes showed a closely linked temporal pattern.

Conclusions:

• Running-induced neurogenesis and decreased perineuronal net expression in the hippocampus are temporally linked.
• A minimum of two weeks of aerobic exercise is required to initiate these changes.