Fetal Alcohol Spectrum Disorder (FASD) covers the broad variety of adverse developmental outcomes found in children as a consequence of prenatal alcohol exposure. The effects observed in FASD range from neurobehavioral abnormalities to embryonic lethality, depending on the developmental stage and severity of the exposure. However, the limited availability of live human brain cells for research has impaired progress toward understanding mechanisms behind FASD. Human pluripotent stem cells (hPSC) are poised to revolutionize our ability to make mechanistic inferences, bridging the gap between traditional model systems and human biology. Differentiation of hPSC allows for the study of brain development in-a-dish, providing a platform with greater accessibility to alcohol exposure experimental manipulation. We hypothesize that alcohol exposure at early stages of human development leads to epigenetic modifications, affecting gene expression and causing physiological changes at the cellular and functional levels.
Our aims are: (i) Determine the transcriptional and epigenetic landscape of alcohol exposure. We will generate hPSC-derived organoids, which recapitulate the mid-fetal human cortical development, and expose them to alcohol at different maturation time points. We will perform unbiased gene expression by RNAseq, followed by DNA methylation profiling. The correlation of this data will reveal the signature of genes that are more dramatically affected by alcohol during neurodevelopment. (ii) Measure the physiological consequences. The anatomical analysis of these human brain organoids will provide information about the consequences of alcohol exposure for cortical cytoarchitecture and layer identity. Cell death and proliferation will be evaluated. We will perform a battery of morphometric and physiological tests to determine the impact of alcohol in hPSC-derived progenitors, neurons, and astrocytes. Real-time synaptogenesis assay will be performed to determine when synapses become defective under alcohol exposure. (iii) Evaluate the neural network alteration and functional rescue. We will investigate neuronal connectivity by evaluating network synchronization using multi-electrode arrays. This technology will allow us to define the subpopulations content of neural cultures affected by alcohol exposure Finally, we will manipulate potential genes and molecular pathways to rescue potentially altered phenotypes. We will perform basic gain and loss of function to rescue the FASD neuronal connectivity defects. We strive to offer a multidisciplinary approach which has the potential to identify biomarkers for FASD could impact the future treatment options for children exposed to alcohol prenatally.
The unavailability of live human brain cells for research has blocked progress toward understanding mechanisms behind mental disorders. This project aims to develop a human cortical system using stem cells to evaluate the impact of alcohol exposure in early development of neuronal networks in fetal alcohol spectrum disorders, offering additional insights into its pathophysiology, and providing a groundwork for more effective treatment regimens at the clinic. Our findings will serve as a proof-of-principle for testing therapeutic drugs in a more holistic and reliable differentiation system, using stem cells derived ?mini-brains?.
