ABSTRACT
Ethanol is a powerful substance and, when consumed during pregnancy, has significant psychoactive and developmental effects on the developing fetus. These abnormalities include growth retardation, neurological deficits, and behavioral and cognitive deficiencies, commonly referred to as fetal alcohol spectrum disorder. The effect of ethanol has been reported to affect cellular development on the embryonic level, however, not much is known about mutations contributing to the influence of ethanol. The purpose of our study was to determine if mutation contribute to changes in differentiation patterning, cell-cycle regulatory gene expression, and DNA methylation in human embryonic stem cells after ethanol exposure. We exposed human embryonic stem cells (with and without know DNA mutations) to a low concentration (20 mM) of ethanol and measured neurosphere proliferation and differentiation, glial protein levels, expression of various cell-cycle genes, and DNA methylation. Ethanol altered cell-cycle gene expression between the two cell lines; however, gene methylation was not affected in ether lines.
Subject(s)
Cell Differentiation/drug effects , Chromosome Aberrations , Embryonic Stem Cells/drug effects , Ethanol/toxicity , Neurons/pathology , Spheroids, Cellular/drug effects , Bromodeoxyuridine/metabolism , Cell Count , Cell Line , Cell Proliferation/drug effects , Cell Shape/drug effects , DNA Methylation/drug effects , Embryonic Stem Cells/cytology , Embryonic Stem Cells/pathology , G2 Phase/drug effects , Gene Expression Regulation/drug effects , Humans , Indoles/metabolism , Mitosis/drug effects , Neurons/drug effects , Neurons/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Spheroids, Cellular/cytology , Spheroids, Cellular/pathologyABSTRACT
Ionotropic receptors are the target for most mood-defining compounds. Chronic exposure to ethanol (EtOH) alters receptor-mediated responses and the numbers of these channels and specific subunits; as well as induces anxiolytic, sedative, and anesthetic activity in the human brain. However, very little is known regarding the effects of EtOH on ionotropic receptor transcription during early human development (preimplantation). Using two separate human embryonic stem cell lines the study shows that low amounts of EtOH (20 mM) alters transcription of the ionotropic subunit GABRB3. Changes in ionotrophic receptor expression influence the central nervous system development and have been shown to produce brain abnormalities in animal models. These results suggest that low concentrations of EtOH can alter ionotropic receptor transcription during early human development (preimplantation), which may be a contributing factor to the neurological phenotypes seen in fetal alcohol spectrum disorder (FASD).
Subject(s)
Embryonic Stem Cells/drug effects , Embryonic Stem Cells/metabolism , Ethanol/pharmacology , Gene Expression Regulation, Developmental/drug effects , Receptors, GABA-A/genetics , Blotting, Western , Cell Line , Densitometry , Gene Expression Profiling , Humans , Receptors, GABA-A/metabolismABSTRACT
Alcohol use is common and consumption during pregnancy has been shown to lead to a myriad of physical and neurologic abnormalities commonly referred to as fetal alcohol spectrum disorder. Substance addiction, which includes alcohol, has been shown to involve the major nicotinic acetylcholine receptor subunit CHRNA5. Using human embryonic stem cells as a model of early human development, we show that low concentrations of ethanol (20mM) can alter the expression of CHRNA5. Changes in CHRNA5 expression is linked to altered GABA and NMDA receptor expression, as well as abnormal development of the frontal cortex. These results suggest that alcohol exposure can alter early neurologic development, which may favor addiction and other developmental abnormalities in unborn children.
