Generating new neurons in the adult brain

Using mice deficient in nestin, a protein that is a component of the part of the cytoskeleton known as intermediate filaments or nanofilaments, the research team led by Prof. Milos Pekny showed that nestin produced in astrocytes has an important role in inhibiting neuronal differentiation. They linked this regulatory function of nestin to the Notch signaling from astrocytes to neighboring neural stem cells. Thus, surprisingly, nestin does not control the generation of neurons by acting within neural stem cells, but indirectly by regulating the neurogenesis-inhibitory Notch signals that neural stem cells receive from astrocytes, important constituents of the neurogenic niche.

Generation and functional integration of new neurons in the adult mammalian hippocampus can lead to the reorganization of the neuronal circuitry, triggering 2 opposing effects: a better formation of new memories and a more pronounced loss of previously acquired memories. And indeed, adult mice lacking nestin have both increased number of newly born neurons in the hippocampus and impaired long-term memory.

Source: New insight into the process of generation of new neurons in the adult brain