ABCB1 and Alzheimer disease: In mouse model of AD and AD patients, BBB benefits the clearance of Aβ aggregates through the efflux of amyloid from the brain by dedicated transporters, such as LRP1 (lipoprotein receptor-related protein-1) and P-glycoprotein,136,137 while vascular risk factors induced microvascular inflammation disrupts BBB and reduces the efflux of Aβ from the brain, leading to Aβ deposits onto the vasculature which further impairs vascular function.138 So vascular risk factors induce a positive feedback loop that leads to chronic impairment of the function of BBB and enhanced aggregation of Aβ.