%0 Journal Article
%T Absence of amyloid ¦Â oligomers at the postsynapse and regulated synaptic Zn2+ in cognitively intact aged individuals with Alzheimer¡¯s disease neuropathology
%A Nicole L Bjorklund
%A Lindsay C Reese
%A V-M. Sadagoparamanujam
%A Valeria Ghirardi
%A Randall L Woltjer
%A Giulio Taglialatela
%J Molecular Neurodegeneration
%D 2012
%I BioMed Central
%R 10.1186/1750-1326-7-23
%X Here we describe the localization of A¦Â oligomers at the postsynapse in hippocampi from AD cases. Notably, however, we also found that while present in soluble fractions, A¦Â oligomers are absent from hippocampal postsynapses in NDAN cases. In addition, levels of phosphorylated (active) CREB, a transcription factor important for synaptic plasticity, are normal in NDAN individuals, suggesting that their synapses are functionally intact. Analysis of Zn2+ showed that levels were increased in both soluble fractions and synaptic vesicles in AD hippocampi, paralleled by a decrease of expression of the synaptic vesicle Zn2+ transporter, ZnT3. Conversely, in NDAN individuals, levels of Zn2+ in soluble fractions were significantly lower than in AD, whereas in synaptic vesicles the levels of Zn2+ were similar to AD, but accompanied by preserved expression of the ZnT3.Taken together, these data illustrate that despite substantial AD neuropathology, A¦Â oligomers, and increased synaptic vesicle Zn2+, susceptible brain tissue in these aged NDAN individuals features, as compared to symptomatic AD subjects, significantly lower total Zn2+ levels and no association of A¦Â oligomers with the postsynapse, which collectively may promote the maintenance of intact cognitive function.
%K A¦Â oligomers
%K Alzheimer¡¯s disease
%K hippocampus
%K asymptomatic
%K zinc
%K synaptic vesicle
%U http://www.molecularneurodegeneration.com/content/7/1/23/abstract