Abstract
BackgroundFetal alcohol syndrome is an important clinical problem. Human embryonic stem cells (hESC) have not been widely used to study developmental alcohol toxicity. Here we document the phenotype of hESC exposed to clinically-relevant, low dose ethanol (20mM). MethodsAll cultures were maintained in 3% O2 to reflect normal physiologic conditions. Undifferentiated hESC were expanded with basic fibroblast growth factor (bFGF), with or without ethanol, then differentiated without ethanol. Proliferation and apoptosis in response to ethanol were assayed, and PCR used to examine expression of GABA receptor subunits. Whole cell patch clamping was used to examine GABAA receptor function in undifferentiated hESC. Immunocytochemistry and western blotting were used to follow differentiation of early neurons, astrocytes, and oligodendrocytes, Principal findingsExposure to 20mM ethanol resulted in larger colonies of undifferentiated hESC despite an increase in apoptosis, because proliferation of the undifferentiated cells (and neuroblasts) was significantly increased. Differentiation of hESC (following a week of ethanol exposure) resulted in decreased expression of GFAP (by western) compared to unexposed cells, suggesting that astrocyte differentiation was reduced, while markers of oligodendrocyte and neuron differentiation were unchanged. At the message level, undifferentiated hESC express all GABAA receptor subunits, but functional receptors were not found by whole cell patch clamping. ConclusionOur results in hESC suggest a complex mix of ethanol-induced phenotypic changes when ethanol exposure occurs very early in development. Not only increased apoptosis, but inappropriate proliferation and loss of trophic astrocytes could result from low-dose ethanol exposure very early in development. More generally, these studies support a role for hESC in developing hypotheses and focusing questions to complement animal studies of developmental toxicities.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
