Enforced Pax6 Expression Rescues Alcohol‐Induced Defects of Neuronal Differentiation in Cultures of Human Cortical Progenitor Cells

Abstract

Background Alcohol is the most widely consumed substance of abuse, and its use during pregnancy can lead to serious disorders of brain development. The precise molecular action of alcohol on human brain development, however, is still unknown. We previously enriched multipotent progenitor cells, radial glia cells, from human fetal forebrain and demonstrated that they express transcription factor Pax6 which is necessary for their neurogenic fate. Methods Enriched human fetal radial glia cells were maintained in vitro as either control or Pax6-expressing retrovirus infected cells. Cultures were treated with increasing doses of alcohol to evaluate Pax6 expression, proliferation and differentiation of radial glia cells by immunocytochemistry, Western Blot and RT-PCR methods. Results In vitro treatment with alcohol reduced the expression of transcription factor Pax6 and proliferation of radial glia cells, which decreased neurogenesis. Consistent with this finding, the over-expression of Pax6 in radial glia cells under alcohol treatment rescued cell proliferation and restored the generation of neurons. In contrast to this effect on neurogenesis, the over-expression of Pax6 inhibits the generation of astroglia regardless of alcohol treatment, implying lineage specific effects. Conclusions These findings suggest that the effect of alcohol on human neurogenesis is partially due to the reduced expression of transcription factor Pax6 in radial glia cells.

Alcohol-Induced Epigenetic Alterations to Developmentally Crucial Genes Regulating Neural Stemness and Differentiation

“…In contrast, Dlx2 and Pax6 both displayed significant differences in mRNA levels relative to the control ( p = 0.015 and p = 0.02 ). Of note, a similar degree of Pax6 mRNA repression was recently reported in a human radial glia progenitor cell model of ethanol exposure (Mo et al, 2012). Collectively, these results indicate that while select candidates display altered levels of gene expression, the transcriptional control of many genes remains unperturbed despite changes in the distribution of H3K4 Me3 and H3K27 Me3 within their regulatory regions.…”

“…Studies using a broad range of model systems representing multiple tissue types reveal exposure to alcohol significantly alters the developmental trajectory of progenitor cells and fundamentally compromises histogenesis (Camarillo and Miranda, 2008; Crabb et al, 2011; Crews et al, 2006; Gong and Wezeman, 2004; Hipp et al, 2010; Ieraci and Herrera, 2007; Mo et al, 2012; Roitbak et al, 2011; Vangipuram and Lyman, 2010; 2012; Vemuri and Chetty, 2005). These observations are highly suggestive that ethanol interferes with the ability of differentiating cells to properly engage the molecular systems necessary to execute cellular differentiation and patterning.…”

Effects of Ethanol on Cellular Composition and Network Excitability of Human Pluripotent Stem Cell‐Derived Neurons

“…In previous stem cell studies, EtOH significantly reduced proliferation and affected the expression of the pluripotency marker Oct4 and the early neuroectodermal transcription factor Pax6, but only at concentrations above 50 mM (Mo et al., ; Ogony et al., ). To determine whether 50 mM EtOH causes reductions in hPSC‐derived progenitor proliferation and/or neuronal specification in our hands, we performed immunocytochemistry as well as FACS (Zhang et al., ).…”

Ethanol induces cytostasis of cortical basal progenitors

“…Our results are consistent with an elegant report that demonstrated a decrease in Tbr2 immunoreactivity in the cortical VZ/SVZ regions of fetal human and mouse slice cultures exposed to ETOH [ 40 ]. Further, another study by Mo et al [ 41 ] illustrated that ETOH affects the expression of Pax6 in RGCs resulting in reduced generation of Tbr2+ cells and young neurons. The difference could be ascribed to the fact that the cells used in the Mo et al, [ 41 ] study is 95 % radial glia origin as opposed to the basal progenitors used in the current study (strong Tbr2 expression; Fig.…”

“…Further, another study by Mo et al [ 41 ] illustrated that ETOH affects the expression of Pax6 in RGCs resulting in reduced generation of Tbr2+ cells and young neurons. The difference could be ascribed to the fact that the cells used in the Mo et al, [ 41 ] study is 95 % radial glia origin as opposed to the basal progenitors used in the current study (strong Tbr2 expression; Fig. 1 ).…”