Exercise may stimulate the growth of new neurons by making other brain cells contract. The discovery, which was in mice, could help explain how exercise boosts brain health and protects against cognitive decline. Being physically active is one of the most important lifestyle factors for maintaining our mental health and guarding against cognitive decline.
In animals, including humans, it is associated with neurogenesis – the growth of new neurons – in the hippocampus, a region involved in learning and memory. Workout patch delivers some of the benefits of exercise with no exertion Although many exercise-induced factors, such as signalling molecules and hormones, have been identified in the blood, how these benefit the brain is unclear. Justin Rhodes at the University of Illinois Urbana-Champaign and his colleagues wondered whether astrocytes are involved.
These star-shaped cells, present in the central nervous system, are among the first to detect circulating molecules and support neurogenesis by releasing substances that help neurons grow and repair. To investigate, the researchers housed 20 mice for two or three days in cages with or without a running wheel. They then measured two molecular markers associated with astrocyte contraction in the hippocampus.
In exercising mice, one marker increased within 1 to 2 minutes of running, while the other was associated with exercise that occurred over the previous 27 to 38 minutes. Next, the researchers placed mouse muscle cells in a dish and collected the substances they released upon spontaneous contraction. They then applied this “muscle medium” to mouse astrocytes to demonstrate that the contraction of muscle cells makes astrocytes contract.
The researchers found that the astrocytes contracted slightly in a medium of ordinary stiffness, but adding the muscle medium increased their force. Finally, the team collected the substances released by the contracting astrocytes and added them to cultures of mice hippocampal neurons. Liquid from astrocytes on stiffer gels, which contracted most strongly, produced the greatest abundance of immature neurons – a sign of neurogenesis.
This suggests that the more astrocytes contract, the more neurogenesis occurs. Previous exposure to the muscle medium increased this further. It’s unclear why astrocyte contraction provokes neurogenesis, but Rhodes suggests it may make the cell membrane easier to cross.
Extract — continue reading at the source.
