A profusion of neural stem cells in the brain of the spiny mouse, Acomys cahirinus

Abstract

The adult mammalian brain contains at least two populations of neural stem/precursor cells (NPCs) which are set a side during development for the function of repair and replacement throughout life (Lim & Alvarez-Bullya, 2016;Obernier & Alvarez-Bullya, 2019). One population is present in the ventricular-subventricular zone (SVZ) on the walls of the lateral ventricle. The neuroblasts generated by these NPCs migrate to the olfactory bulbs which are a considerable distance rostrally by chain migration along a course called the rostral migratory stream (RMS). There they become incorporated into the olfactory circuitry as functional interneurons contributing to fine odor discrimination. It is estimated that many thousands of new olfactory neurons are produced each day in the rodent brain.The second population of NSCs is present in the dentate gyrus of the hippocampus and pass through a series of developmental stages to become incorporated into the hippocampal circuitry as dentate granule neurons (Goncalves et al., 2016). Here they are involved in learning, memory and pattern separation.Both populations of NSCs have been investigated with the aim of improving the human condition. In the hippocampus, for example, methods to improve their rate of production, rate of differentiation or slowing their rate of loss during ageing are of considerable interest since if this were to translate to humans the implications for learning and memory in elderly populations or in neurological disease could be highly significant. In this regard, several growth factors and signaling molecules such as Wnt, Shh, BMP, and Notch play crucial roles in the promotion of NSC

Coronal brain atlas in stereotaxic coordinates of the African spiny mouse, Acomys cahirinus

“…Interestingly, apart from the gerbil that also presents a similar undulated configuration of the dentate gyrus (Radtke-Schuller et al 2016), this format was not reported so far in the brain of other rodents. In the study of Maden et al (2021), the undulated dentate gyrus of A. cahirinus brain (contrasting to the linear format of the Mus) is also apparent, although this is not so evident as in our study, probably due to the fact that these authors performed sagittal sections in contrast to the coronal sections performed here.…”

“…In the study of Maden et al. (2021), the undulated dentate gyrus of A. cahirinus brain (contrasting to the linear format of the Mus ) is also apparent, although this is not so evident as in our study, probably due to the fact that these authors performed sagittal sections in contrast to the coronal sections performed here.…”

“…Surprisingly, little is known concerning the Acomys central nervous system. Very recently, Maden et al (2021) examined stem cell populations in the A. cahirinus brain in comparison to M. musculus and described that these cell niches are localized in the same brain regions in both animals. In the present atlas, we observe a peculiar arrangement of the dentate gyrus in the brain of A. cahirinus, with an undulated granular cell layer.…”

“…Neurobiology of Acomys remains fundamentally unexplored, and particularly the lack of a stereotaxic brain atlas has limited studies on the ability of brain repair in this model. Recently, neurogenic niches were identified in Acomys brain with identical localization compared with Mus (Maden et al., 2021). Stereotaxic brain atlases of the mouse ( Mus musculus ) and rat ( Rattus norvegicus ) have been fundamental for the development of several rodent models of neurological disease and for a vast number of experimental approaches in neuroscience.…”