Widespread Proliferation Impairment and Hypocellularity in the Cerebellum of Fetuses with Down Syndrome
Article first published online: 6 DEC 2010
© 2010 The Authors; Brain Pathology © 2010 International Society of Neuropathology
Volume 21, Issue 4, pages 361–373, July 2011
How to Cite
Guidi, S., Ciani, E., Bonasoni, P., Santini, D. and Bartesaghi, R. (2011), Widespread Proliferation Impairment and Hypocellularity in the Cerebellum of Fetuses with Down Syndrome. Brain Pathology, 21: 361–373. doi: 10.1111/j.1750-3639.2010.00459.x
- Issue published online: 13 JUN 2011
- Article first published online: 6 DEC 2010
- Accepted manuscript online: 29 OCT 2010 01:40PM EST
- Received 19 August 2010; accepted 18 October 2010.
- mental retardation;
- trisomy 21
Evidence in mouse models for Down syndrome (DS) and human fetuses with DS clearly shows severe neurogenesis impairment in various telencephalic regions, suggesting that this defect may underlie the cognitive abnormalities of DS. As cerebellar hypotrophy and motor disturbances are part of the clinical features of DS, the goal of our study was to establish whether these defects may be related to neurogenesis impairment during cerebellar development. We found that in fetuses with DS (17–21 weeks of gestation) the cerebellum had an immature pattern, a reduced volume and notably fewer cells (−25%/−50%) in all cerebellar layers. Immunohistochemistry for Ki-67, a marker of cycling cells, showed impaired proliferation (−17%/−50%) of precursors from both cerebellar neurogenic regions (external granular layer and ventricular zone). No differences in apoptotic cell death were found in DS vs. control fetuses. The current study provides novel evidence that in the cerebellum of DS fetuses there is a generalized hypocellularity and that this defect is due to proliferation impairment, rather than to an increased cell death. The reduced proliferation potency found in the DS fetal cerebellum, in conjunction with previous evidence, strengthens the idea that the trisomic brain is characterized by widespread neurogenesis disruption.