Project description:To understand how the circadian clock regulates astrocyte physiology, we conducted a circadian transcriptome analysis in cultured mouse cortical astrocytes
Project description:In this study, we used human cortical organoids (hCOs) derived from induced pluripotent stem cells (iPSCs) to examine how hypoxia exposure interferes with astrocyte synapse engulfment at 6 months in culture and 10 months in culture, equivalent to mid fetal- or neonatal-equivalent stages of development, respectively. We identified that hypoxia inhibits the synaptosome engulfment by human astrocytes at both developmental stages, with a more pronounced phenotype in 10 months astrocytes. Transcriptional analyses revealed disruptions in circadian rhythm pathways in hypoxic astrocytes, but not neurons, and PER2 luciferase assays (PER2::LUC) validated the presence of circadian rhythms and their disruption by hypoxia in intact hCOs, with more pronounced rhythms in 10 months hCOs.
Project description:Astrocytes are implicated in neuronal development, particularly excitatory synaptogenesis, but their genome-wide impact is unclear. Using cell-type specific RNA-seq we show that cortical astrocytes induce widespread transcriptomic changes in developing cortical neurons. Rat cortical neurons were maintained in the presence or absence of mouse astrocytes, RNA-seq performed, and mixed-species RNA-seq reads sorted according to species. Cultures were also treated with TTX to abolish neuronal firing activity, to investigate the effects of the presence or absence activity-dependent signalling.
Project description:We and other groups doumented that astrocytes modulate migration, maturation and myelin sythesis of oligodendrocytes through release of neurotransmitters, cytokins and other signaling molecules. However, much less is known about on how the oligodendrocytes affects the astrocytes. We compared the transcriptome of cortical astrocytes when cultured alone and co-cultured with non-touching immortalized precursor oligodendrocytes (Oli-neu) in insert systems. Experimental data indicate that the oligodendrocyte-conditioning medium has a substantial effect on the the gene expression in astrocytes. Moreover, oligodendendrocyte proximity remodels major astrocyte functional pathways.
Project description:Astrocytes are implicated in neuronal development, particularly excitatory synaptogenesis, but their genome-wide impact is unclear. Using cell-type specific ChIP-seq we show that cortical astrocytes induce widespread changes in developing cortical neurons in histone marks associated with active open chromatin and repressed/condensed chromatin. Rat cortical neurons were maintained in the presence or absence of mouse astrocytes, ChIP-seq performed, and mixed-species ChIP-seq reads sorted according to species.
Project description:Cortical human fetal astrocytes, density 8-15000 cells/cm2 ( ScienCell, San Diego, CA, USA) seeded in Astrocyte medium (ScienCell, San Diego, CA, USA). Further info in "Proteomic and metabolomic characterization of human neurovascular unit cells in response to methamphetamine" Herland et al Adv Biosystems 2020
Project description:Illumina RNA sequencing technology was used to determine transcriptome changes in cultured mouse cortical neurons infected with lentivirus expressing shMeCP2