For proliferation studies, Brd U was injected at E13.5 and 30 min before decapitation of dam. Sections were treated with primary antibody overnight at 4 °C in 5% normal donkey or goat serum/PBS with 0.1% Tween-20 or Triton-X 100 followed by the appropriate fluorescently conjugated secondary antibody.
Compounding the heterogeneity of the influence of Ascl1 on glial progenitors, it was recently shown in the spinal cord that Ascl1 affects both astrocytes and oligodendrocytes differentially in grey matter and white matter.The exact timing of the transition from neurogenesis to gliogenesis and the subsequent differentiation of glial lineages remains unknown for most of the Central Nervous System (CNS), and is especially true for the hypothalamus.Here we used mouse embryonic brain samples to determine the onset of gliogenesis and expansion of glial populations in the tuberal hypothalamus using glial markers Sox9, Sox10, Olig2, Pdgf Rα, Aldh1L1, and MBP.These progenitors further mature and start to migrate outwards after starting to express Sox10 and Pdgf Rα.Once in the mantle region, these glioblasts begin to actively proliferate and give rise to the many oligodendrocyte precursor cells (OPCs) that are necessary to adequately populate the mantle region.Using The tuberal hypothalamus, consisting of the ventromedial hypothalamus (VMH), dorsomedial hypothalamus (DMH), and arcuate nucleus (ARC), is a key regulator of many important biological functions, such as energy balance, sexual behavior, thermoregulation, and affective functioning .
Although most of the research within this brain region is focused on understanding neuronal differentiation and function, the glial cells that interact with hypothalamic neurons also play a critical role in controlling homeostatic mechanisms, particularly aspects of feeding regulation .
Temporally, these OPCs continue to mature and upon reaching their final maturation, these oligodendrocytes begin to myelinate axons .
Yet, despite considerable understanding of glial development in other brain regions, primarily the cortex and spinal cord, the timing for gliogenesis in the hypothalamus remains undefined.
We also employed -null mice to investigate the influence of these b HLH transcription factors in the progression of gliogenesis in this brain region.
By characterizing the development of oligodendrocytes in this important brain region, we will be poised to better understand how disruption of gliogenesis might contribute to hypothalamic disease states, such as obesity.] were bred to obtain embryonic tissue samples.
We further employed Using marker analyses for glial precursors, we found that gliogenesis commences just prior to E13.5 in the tuberal hypothalamus, beginning with the detection of glioblast and oligodendrocyte precursor cell markers in a restricted domain adjacent to the third ventricle.