PURPOSE: To assess whether the effects of cranial (56)Fe irradiation on the spatial memory of mice in the water maze are sex and apolipoprotein E (apoE) isoform dependent and whether radiation-induced changes in spatial memory are associated with changes in the dendritic marker microtubule-associated protein 2 (MAP-2) and the presynaptic marker synaptophysin. METHODS AND MATERIALS: Two-month-old male and female mice expressing human apoE3 or apoE4 received either a 3-Gy dose of cranial (56)Fe irradiation (600 MeV/amu) or sham irradiation. Mice were tested in a water maze task 13 months later to assess effects of irradiation on spatial memory retention. After behavioral testing, the brain tissues of these mice were analyzed for synaptophysin and MAP-2 immunoreactivity. RESULTS: After irradiation, spatial memory retention of apoE3 female, but not male, mice was impaired. A general genotype deficit in spatial memory was observed in sham-irradiated apoE4 mice. Strikingly, irradiation prevented this genotype deficit in apoE4 male mice. A similar but nonsignificant trend was observed in apoE4 female mice. Although there was no change in MAP-2 immunoreactivity after irradiation, synaptophysin immunoreactivity was increased in irradiated female mice, independent of genotype. CONCLUSIONS: The effects of (56)Fe irradiation on the spatial memory retention of mice are critically influenced by sex, and the direction of these effects is influenced by apoE isoform. Although in female mice synaptophysin immunoreactivity provides a sensitive marker for effects of irradiation, it cannot explain the apoE genotype-dependent effects of irradiation on the spatial memory retention of the mice.
PURPOSE: To assess whether the effects of cranial (56)Fe irradiation on the spatial memory of mice in the water maze are sex and apolipoprotein E (apoE) isoform dependent and whether radiation-induced changes in spatial memory are associated with changes in the dendritic marker microtubule-associated protein 2 (MAP-2) and the presynaptic marker synaptophysin. METHODS AND MATERIALS: Two-month-old male and female mice expressing humanapoE3 or apoE4 received either a 3-Gy dose of cranial (56)Fe irradiation (600 MeV/amu) or sham irradiation. Mice were tested in a water maze task 13 months later to assess effects of irradiation on spatial memory retention. After behavioral testing, the brain tissues of these mice were analyzed for synaptophysin and MAP-2 immunoreactivity. RESULTS: After irradiation, spatial memory retention of apoE3 female, but not male, mice was impaired. A general genotype deficit in spatial memory was observed in sham-irradiated apoE4mice. Strikingly, irradiation prevented this genotype deficit in apoE4 male mice. A similar but nonsignificant trend was observed in apoE4 female mice. Although there was no change in MAP-2 immunoreactivity after irradiation, synaptophysin immunoreactivity was increased in irradiated female mice, independent of genotype. CONCLUSIONS: The effects of (56)Fe irradiation on the spatial memory retention of mice are critically influenced by sex, and the direction of these effects is influenced by apoE isoform. Although in female micesynaptophysin immunoreactivity provides a sensitive marker for effects of irradiation, it cannot explain the apoE genotype-dependent effects of irradiation on the spatial memory retention of the mice.
Authors: Gwendolen E Haley; Laura Villasana; Catherine Dayger; Matthew J Davis; Jacob Raber Journal: Int J Radiat Oncol Biol Phys Date: 2012-03-06 Impact factor: 7.038
Authors: Jessica Minnier; Mark R Emmett; Ruby Perez; Liang-Hao Ding; Brooke L Barnette; Rianna E Larios; Changjin Hong; Tae Hyun Hwang; Yongjia Yu; Christina M Fallgren; Michael D Story; Michael M Weil; Jacob Raber Journal: Sci Rep Date: 2021-07-21 Impact factor: 4.379
Authors: Gwendolen E Haley; Lauren Yeiser; Reid H J Olsen; Matthew J Davis; Lance A Johnson; Jacob Raber Journal: Radiat Res Date: 2013-03-19 Impact factor: 2.841