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Oligomeric amyloid-beta peptide disrupts phosphatidylinositol-4,5-bisphosphate metabolism.

Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, College of Physicians and Surgeons, 630 West 168th Street, New York, New York 10032, USA.
Nature Neuroscience (Impact Factor: 14.98). 06/2008; 11(5):547-54. DOI: 10.1038/nn.2100
Source: PubMed

ABSTRACT Synaptic dysfunction caused by oligomeric assemblies of amyloid-beta peptide (Abeta) has been linked to cognitive deficits in Alzheimer's disease. Here we found that incubation of primary cortical neurons with oligomeric Abeta decreases the level of phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P2), a phospholipid that regulates key aspects of neuronal function. The destabilizing effect of Abeta on PtdIns(4,5)P2 metabolism was Ca2+-dependent and was not observed in neurons that were derived from mice that are haploinsufficient for Synj1. This gene encodes synaptojanin 1, the main PtdIns(4,5)P2 phosphatase in the brain and at the synapses. We also found that the inhibitory effect of Abeta on hippocampal long-term potentiation was strongly suppressed in slices from Synj1+/- mice, suggesting that Abeta-induced synaptic dysfunction can be ameliorated by treatments that maintain the normal PtdIns(4,5)P2 balance in the brain.

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