Clusterin contributes to early stage of Alzheimer's disease pathogenesis

摘要

Abstract While clusterin is reportedly involved in Alzheimer's disease ( AD ) pathogenesis, how clusterin interacts with amyloid‐β (A?) to cause A? neurotoxicity remains unclear in vivo . Using 5× FAD transgenic mice, which develop robust AD pathology and memory deficits when very young, we detected interactions between clusterin and A? in the mouse brains. The two proteins were concurrently upregulated and bound or colocalized with each other in the same complexes or in amyloid plaques. Neuropathology and cognitive performance were assessed in the progeny of clusterin‐null mice crossed with 5× FAD mice, yielding clu ?/? ;5× FAD and clu +/+ ;5× FAD . We found far less of the various pools of A? proteins, most strikingly soluble A? oligomers and amyloid plaques in clu ?/? ;5× FAD mice at 5 months of age. At that age, those mice also had higher levels of neuronal and synaptic proteins and better motor coordination, spatial learning and memory than age‐matched clu +/+ ;5× FAD mice. However, at 10 months of age, these differences disappeared, with A? and plaque deposition, neuronal and synaptic proteins and impairment of behavioral and cognitive performance similar in both groups. These findings demonstrate that clusterin is necessarily involved in early stages of AD pathogenesis by enhancing toxic A? pools to cause A?‐directed neurodegeneration and behavioral and cognitive impairments, but not in late stage.