Age-related effects of X-ray irradiation on mouse hippocampus

Identifier:  PC:1653

Handle: https://hdl.handle.net/20.500.11797/PC1653

Authors:  Montserrat Bellés; Arianna Casciati; Katalin Dobos; Francesca Antonelli; Anett Benedek; Stefan J. Kempf; Andrea Balogh; Mirella Tanori; Luis Heredia; Michael J. Atkinson; Christine von Toerne; Omid Azimzadeh; Anna Saran; Geza Sáfrány; Mohammed A. Benotmane; M. Victoria Linares-Vidal; Soile Tapio; Katalin Lumniczky; Simonetta Pazzaglia

Abstract:
Therapeutic irradiation of pediatric and adult patients can profoundly affect adult neurogenesis, and cognitive impairment manifests as a deficit in hippocampal-dependent functions. Age plays a major role in susceptibility to radiation, and younger children are at higher risk of cognitive decay when compared to adults. Cranial irradiation affects hippocampal neurogenesis by induction of DNA damage in neural progenitors, through the disruption of the neurogenic microenvironment, and defective integration of newborn neurons into the neuronal network. Our goal here was to assess cellular and molecular alterations induced by cranial X-ray exposure to low/moderate doses (0.1 and 2 Gy) in the hippocampus of mice irradiated at the postnatal ages of day 10 or week 10, as well as the dependency of these phenomena on age at irradiation. To this aim, changes in the cellular composition of the dentate gyrus, mitochondrial functionality, proteomic profile in the hippocampus, as well as cognitive performance were evaluated by a multidisciplinary approach. Our results suggest the induction of specific alterations in hippocampal neurogenesis, microvascular density and mitochondrial functions, depending on age at irradiation. A better understanding of how irradiation impairs hippocampal neurogenesis at low and moderate doses is crucial to minimize adverse effects of therapeutic irradiation, contributing also to radiation safety regulations.