Fig. 5

Vitamin D3 supplementation reduces amyloid plaque load and cognitive deficits in transgenic animals. a In the three assessed brain regions - frontal cortex, hippocampus and neocortex – the number of amyloid plaques is reduced in transgenic supplemented brains. Vitamin D3 treatment limits astrogliosis (GFAP staining) in the frontal cortex and neocortex (b) and increases microglial activation (IBA1 staining) in the frontal cortex (c) of transgenic mice. Cognitive performance was assessed using the Y-maze and the radial arm water maze. d Vitamin D3 supplemented transgenic mice do not display the decreased percent of alternation (Y maze) observed in unsupplemented transgenic mice over time as measured at M4, M6 and M8. e, f At the end of the supplementation period (M8), a significant decrease in percent alternation performance is observed in transgenic mice. This effect is rescued by vitamin D3 supplementation with no significant difference in the number of arms entered. g Using the radial arm water maze, hippocampal-dependent spatial working memory was assessed. At the end of the learning process (Day 3), a significantly reduced number of errors is observed in supplemented transgenic mice. * = p < 0.05; ** = p < 0.01