Delayed maturation of newborn neurons in the aging hippocampus

TRINCHERO MF; SCHINDER AF

Congreso; 2nd Eurogenesis Meeting; 2013

Neural progenitor cells of the adult dentate gyrus can differentiate and develop into fully functional neurons. Adult neurogenesis is tightly regulated by several physiological conditions. For instance, we have recently demonstrated that the timing of neuronal maturation is regulated by the activity of the surrounding networks. Since aging is one important factor associated to decreased rates of neuronal production, in the present work we investigated whether maturation of adult born neurons was also affected by age. To approach this question we used retroviral labeling of adult born neurons to compare granule cells developing in two, five and eight month old mice (work in progress). We have analyzed the morphology and expression of neuronal markers at different stages of neuronal development (dpi; days post infection). Fourteen and 21 dpi neurons in five month old mice displayed immature features when compared to neurons of the same age in two month old mice; however, similar levels of maturity were observed by 28 dpi. Such delayed maturation in the aged hippocampus seems to correlate to reduced levels of network activity (measured by ARC expression in the dentate gyrus). Interestingly, the observed delay was reverted by housing mice with a running wheel. We are currently investigating the mechanisms underlying the age dependent delay in neuronal maturation.