January 26, 2009
UNIT 9: Human BiologyNovel Brain Region for Mammalian Neurogenesis
Adult neurogenesis is a mysterious phenomenon. Previously, scientists thought that adult neurogenesis, or the birth of new neurons, occurred most often in lower vertebrates such as frogs or fish. In mammals such as mice and rats, adult neurogenesis was thought to be rare, and restricted to two particular brain regions.
However, two groups of scientists at the University of Turin in Italy have recently documented neurogenesis in adult rabbits. Surprisingly, the birth of progenitor cells appears to occur in the cerebellum, a brain region previously thought to lack cell turnover in adulthood.
In mammals, progenitor cells typically originate from remnants of embryonic cell layers, such as the ventricular zone or the olfactory bulb. The progenitor cells identified in the current study are generated from neuronal progenitor cells in the functional tissue of the brain, suggesting that these cells might have great potential for the repair of neural damage in adult tissue.
While rabbits do live longer than other model organisms for adult neurogenesis, and thus might have a different neural development profile, this work gives new hope to the study of adult neurogenesis in humans.