Data from: Neuronal migration depends on blood flow in the adult mammalian brain

In animal tissues, several cell types migrate along blood vessels, raising
the possibility that blood flow influences cell migration. Here, we show
that blood flow promotes the migration of new olfactory-bulb neurons in
the adult brain. Neuronal migration is facilitated by blood flow, leading
to the accumulation of new neurons near blood vessels with abundant blood
flow. Blood flow inhibition attenuates blood vessel-guided neuronal
migration, suggesting that blood contains factors beneficial to neuronal
migration. We found that ghrelin, which is increased in the blood by
hunger, directly influences neuronal migration. Ghrelin signaling promotes
somal translocation by activating actin cytoskeleton contraction at the
rear of the cell soma. New neurons mature in the olfactory bulb and
contribute to the olfactory function for sensing odorants from food.
Finally, we show that neuronal migration is increased by calorie
restriction and that ghrelin signaling is involved in the process. This
study suggests that blood flow promotes neuronal migration through
blood-derived ghrelin signaling in the adult brain, which could be one of
the mechanisms that improve the olfactory function for food-seeking
behavior during starvation.