Altered apolipoprotein e glycosylation is associated with Aβ(42) accumulation in an animal model of Niemann-Pick Type C disease

Abstract

Neurodegeneration is the final cause of death in Niemann-Pick Type C (NPC) disease, a cholesterol-storage disorder. Accumulating evidence indicates that NPC may share common pathological mechanisms with Alzheimer's disease, including the link between aberrant cholesterol metabolism and amyloid-β (Aβ) deposition. Apolipoprotein E (apoE) is highly expressed in the brain and plays a pivotal role in cholesterol metabolism. ApoE can also modulate Aβ production and clearance, and it is a major genetic risk factor for Alzheimer's disease. Although apoE is glycosylated, the functional significance of this chemical alteration on Aβ catabolism is unclear. In this study using an NPC animal model, we detect specific changes in apoE glycosylation that correlate with increased Aβ(42) accumulation prior to the appearance of neurological abnormalities. This suggests that increased apoE expression could be a compensatory response to the increased Aβ(42) deposition in NPC nih mice. We also observe what appears to be a simplification of the glycosylation process on apoE during neurodegeneration. © 2010 International Society for Neurochemistry.