Lack of association between the levels of the low-density lipoprotein receptor-related protein (LRP) and either Alzheimer dementia or LRP exon 3 genotype

The low-density lipoprotein receptor-related protein (LRP), which interacts with the Alzheimer disease (AD) beta-amyloid precursor protein (APP), represents an important pathway in AD pathology. LRP-mediated receptor pathways appear to regulate both the production and the clearance of amyloid beta-protein (Abeta), a principal neuropathological product in AD. Several conflicting studies have examined levels of LRP in AD brains, as well as the relationship between the LRP exon 3 (C766T) polymorphism and LRP levels and/or disease susceptibility. In order to further investigate the role of LRP in AD, we examined well-characterized brain samples collected from subjects with varying degrees of cognitive impairment for LRP protein expression levels as well as for the presence of the LRP exon 3 polymorphism. We found no correlation between LRP levels and either presence of the disease or cognitive decline. In addition, we found no correlation between the LRP exon 3 polymorphism and either AD or LRP levels.