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Prenatal ethanol exposure impairs the formation of radial glial fibers and promotes the transformation of GFAP??positive radial glial cells into astrocytes.

ABSTRACT: During embryonic cortical development, radial glial cells (RGCs) are the major source of neurons, and these also serve as a supportive scaffold to guide neuronal migration. Similar to Vimentin, glial fibrillary acidic protein (GFAP) is one of the major intermediate filament proteins present in glial cells. Previous studies confirmed that prenatal ethanol exposure (PEE) significantly affected the levels of GFAP and increased the disassembly of radial glial fibers. GFAP? is a variant of GFAP that is specifically expressed in RGCs; however, to the best of our knowledge, there are no reports regarding how PEE influences its expression during cortical development. In the present study, the effects of PEE on the expression and distribution of GFAP? during early cortical development were assessed. It was found that PEE significantly decreased the expression levels of GFAP and GFAP?. Using double immunostaining, GFAP? was identified to be specifically expressed in apical and basal RGCs, and was co?localized with other intermediate filament proteins, such as GFAP, Nestin and Vimentin. Additionally, PEE significantly affected the morphology of radial glial fibers and altered the behavior of RGCs. The loss of GFAP? accelerated the transformation of RGCs into astrocytes. Using co?immunostaining with Ki67 or phospho?histone H3, GFAP?+ cells were observed to be proliferative or mitotic cells, and ethanol treatment significantly decreased the proliferative or mitotic activities of GFAP?+ RGCs. Taken together, the results suggested that PEE altered the expression patterns of GFAP? and impaired the development of radial glial fibers and RGC behavior. The results of the present study provided evidence that GFAP? may be a promising target to rescue the damage induced by PEE.

SUBMITTER: Li Y

PROVIDER: S-EPMC7893684 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Prenatal ethanol exposure impairs the formation of radial glial fibers and promotes the transformation of GFAPδ‑positive radial glial cells into astrocytes.

Li Yu Y Zhang Li-Na LN Chong Li L Liu Yue Y Xi Feng-Yu FY Zhang Hong H Duan Xiang-Long XL

Molecular medicine reports 20210212 4

During embryonic cortical development, radial glial cells (RGCs) are the major source of neurons, and these also serve as a supportive scaffold to guide neuronal migration. Similar to Vimentin, glial fibrillary acidic protein (GFAP) is one of the major intermediate filament proteins present in glial cells. Previous studies confirmed that prenatal ethanol exposure (PEE) significantly affected the levels of GFAP and increased the disassembly of radial glial fibers. GFAPδ is a variant of GFAP that ...[more]

PMID: 33576465

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Prenatal ethanol exposure impairs the formation of radial glial fibers and promotes the transformation of GFAP??positive radial glial cells into astrocytes.

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Prenatal ethanol exposure impairs the formation of radial glial fibers and promotes the transformation of GFAPδ‑positive radial glial cells into astrocytes.

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