Adult neurogenesis in the short-lived teleost Nothobranchius furzeri: localization of neurogenic niches, molecular characterization and effects of aging
- Authors
- Terzibasi Tozzini, E., Baumgart, M., Battistoni, G., and Cellerino, A.
- ID
- ZDB-PUB-120105-49
- Date
- 2012
- Source
- Aging Cell 11(2): 241-251 (Journal)
- Registered Authors
- Cellerino, Alessandro
- Keywords
- neuronal stem cells, aging, doublecortin, microRNA, gliosis, animal model
- MeSH Terms
-
- Aging*
- Animals
- Cell Survival
- Fishes/metabolism*
- Neurogenesis*
- Neurons/cytology*
- Neurons/metabolism
- PubMed
- 22171971 Full text @ Aging Cell
We studied adult neurogenesis in the short-lived annual fish Nothobranchius furzeri and quantified the effects of aging on the mitotic activity of the neuronal progenitors and the expression of glial fibrillary acid protein (GFAP) in the radial glia.
The distribution of neurogenic niches is substantially similar to that of zebrafish and adult stem cells generate neurons which persist in the adult brain. As opposed to zebrafish, however, the N.furzeri genome contains a doublecortin (DCX) gene. DCX is transiently expressed by newly generated neurons in the telencephalon and optic tectum. We also analyzed expression of the microRNA miR-9 and miR-124 and found that they have complementary expression domains: miR-9 is expressed in the neurogenic niches of the telencephalon and the radial glia of the optic tectum, while miR-124 is expressed in differentiated neurons.
The main finding of this paper is the demonstration of an age-dependent decay in adult neurogenesis. Using unbiased stereological estimates of cell numbers, we detected an almost 5-fold decrease in the number of mitotically-active cells in the optic tectum between young and old age. This reduced mitotic activity is paralleled by a reduction of DCX labelling.
Finally, we detected a dramatic up-regulation of GFAP in the radial glia of the aged brain. This up-regulation is not paralleled by a similar up-regulation of S100B and Musashi-1, two other markers of the radial glia.
In summary, the brain of N.furzeri replicates two typical hallmarks of mammalian aging: gliosis and reduced adult neurogenesis.