Aging-induced Microbleeds of the Mouse Thalamus Compared to Sensorimotor and Memory Defects

Abstract The aim of the present study was to investigate the relationship between aging and brain vasculature health. Three age groups of mice, 3 months, 17-18 months and 24 months, comparable to young adult, middle age and old human individuals were studied. Prussian blue histology, and FISP T2*-weighted MRI were used to quantify structural changes in the brain across age groups. The Novel Object Recognition (NOR) test was used to assess behavioral changes associated with anatomical changes. The present study is the first to show that the thalamus is the most vulnerable brain region in the mouse model for aging-induced vascular damage. MRI data presented here document the timeline of accumulation of thalamic damage. Histological data reveal that the majority of vascular damage accumulates in the ventroposterior nucleus (VP) and mediodorsal thalamic nucleus(MD). Functional studies indicate that aging-induced vascular damage in the thalamus is associated with memory and sensorimotor deficits. The present study points to the possibility that aging-associated vascular disease may be a factor in irreversible brain damage as early as middle age.