Exercise may create new neurons by making other brain cells contract
Physical activity causes a type of brain cell called astrocytes to contract, which then leads to the formation of new neurons, according to a study in mice
Exercise may trigger the growth of new brain cells by causing other cells to contract, a phenomenon discovered in mice. This finding could shed light on how physical activity enhances brain health and wards off cognitive decline. Engaging in regular exercise is a crucial lifestyle choice for preserving mental well-being and preventing cognitive decline in both animals and humans.
The phenomenon is linked to neurogenesis, the generation of new neurons in the hippocampus, a brain region crucial for learning and memory. While numerous exercise-related factors circulating in the blood have been identified, their specific benefits to the brain remain elusive. Justin Rhodes at the University of Illinois Urbana-Champaign and his colleagues hypothesized that astrocytes, star-shaped cells in the central nervous system, might be involved.
These cells can detect circulating molecules and aid neurogenesis by releasing substances that promote neuron growth and repair. The researchers housed 20 mice in cages with or without running wheels for two to three days, subsequently measuring two molecular markers related to astrocyte contraction in the hippocampus. In mice that exercised, one marker surged within 1 to 2 minutes of running, while the other was linked to exercise that took place over the preceding 27 to 38 minutes.
"Both markers indicate that astrocytes contract during exercise," explains Rhodes. Subsequently, the researchers exposed mouse muscle cells to substances released by contracting muscle cells and observed that these cells contracted in response. Adding this "muscle medium" to mouse astrocytes increased their contraction force. Moreover, substances released by contracting astrocytes, particularly those from stiffer gels, produced a higher number of immature neurons, a sign of neurogenesis.
This suggests that the more astrocytes contract, the greater the likelihood of neurogenesis. The researchers hypothesize that astrocyte contraction may make the cell membrane more permeable or facilitate the release of vesicles containing essential chemicals, such as growth factors, to neighboring neurons. While the exact mechanisms remain unclear, this novel discovery could pave the way for new therapies aimed at boosting cognitive function and brain health, particularly for individuals unable to exercise.
Written by urgent.news from New Scientist's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
