Journal
MOLECULAR NEUROBIOLOGY
Volume 55, Issue 1, Pages 751-762Publisher
HUMANA PRESS INC
DOI: 10.1007/s12035-016-0343-z
Keywords
Astrocyte; Synapse; Growth factors; And heterogeneity
Categories
Funding
- Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)
- Ministerio da Saude
- Fundacao Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ)
- Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)
Ask authors/readers for more resources
Astrocytes, the most abundant glial cells in the central nervous system (CNS), comprise a heterogeneous population of cells. However, how this heterogeneity impacts their function within brain homeostasis and response to injury and disease is still largely unknown. Recently, astrocytes have been recognized as important regulators of synapse formation and maturation. Here, we analyzed the synaptogenic property of astrocytes from different regions of the CNS. The effect of conditioned medium derived from astrocytes (astrocyte-conditioned medium (ACM)) from cerebral cortex, hippocampus, midbrain and cerebellum, in synapse formation, was evaluated. Synapse formation was analyzed by quantification of pre- and postsynaptic proteins, synaptophysin, and postsynaptic density protein 95 (PSD-95). ACM from the four regions increased significantly the number of synaptophysin/PSD-95 puncta on neurons from the same and different brain regions. Differences on astrocytic synaptogenic potential between the regions were observed according to ACM protein concentration. Thus, cerebellar astrocytes have higher synaptogenic effect when ACM is less concentrated. Also, heterotypical co-culture assays revealed that neurons from cerebral cortex and midbrain equally respond to ACM, indicating that differences in synapse effect are unlike to be neuron-autonomous. The expression profile of the synaptogenic molecules secreted by astrocytes from distinct brain regions was analyzed by qPCR. Gene expression of glypicans 4 and 6, hevin, and secreted protein-acidic and rich in cysteine (SPARC) greatly varies between astrocytes from different brain regions. Furthermore, in vivo analysis of hevin protein confirmed that variance. These findings highlight the heterogeneity of astrocytes and suggest that their synaptogenic potential may be different in each brain region, mainly due to distinct gene expression profiles.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available