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Cartier, E.

Publications and source records attributed to Cartier, E..

2 recordsLinked to original sources
bioRxiv2024

Long-lived adult-born hippocampal neurons promote successful cognitive aging

Aging is commonly associated with a decline in memory abilities, yet some individuals remain resilient with preserved memory abilities. Memory processing is critically dependent on adult neurogenesis, a unique form of plasticity in the hippocampus. However, it remains unknown if cognitive aging influences the integration and role of adult-born hippocampal neurons (ABNs) generated early in adult life. Here, we investigated the role of long-lived ABNs in rats characterized as either resilient or vulnerable to cognitive aging using a peudo-longitudinal approach. Our findings reveal that long-lived ABNs support successful cognitive aging by preserving their synaptic inputs onto the proximal segments of their dendrites, and that these proximal synaptic sites also demonstrate a maintenance of their mitochondrial homeostasis. Furthermore, by-passing the reduced inputs of ABNs in vulnerable rats through direct optogenetic stimulation successfully improved their memory abilities. Overall, our data indicate that the maintenance of long-lived ABNs integration within the neuronal network is essential for successful cognitive aging, highlighting their potential as a therapeutic target for restoring cognitive functions in old age. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=141 SRC="FIGDIR/small/604332v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@524afforg.highwire.dtl.DTLVardef@b9b2b1org.highwire.dtl.DTLVardef@182a19corg.highwire.dtl.DTLVardef@1402b64_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗
bioRxiv2023

Genetic labeling of embryonically-born dentate granule neurons in young mice using the PenkCre mouse line

The dentate gyrus (DG) of the hippocampus is a mosaic of dentate granule neurons (DGNs) accumulated throughout life. While many studies focused on the morpho-functional properties of adult-born DGNs, much less is known about DGNs generated during development, and in particular those born during embryogenesis. One of the main reasons for this gap is the lack of methods available to specifically label and manipulate embryonically-born DGNs. Here, we have assessed the relevance of the PenkCre mouse line as a genetic model to target this embryonically-born population. In young animals, PenkCre expression allows to tag neurons in the DG with positional, morphological and electrophysiological properties characteristic of DGNs born during the embryonic period. In addition, PenkCre+ cells in the DG are distributed in both blades along the entire septo-temporal axis. This model thus offers new possibilities to explore the functions of this underexplored population of embryonically-born DGNs.

neuroscience↗