Increased Expression of Readthrough Acetylcholinesterase Variants in the Brains of Alzheimer's Disease Patients
Por:
Campanari ML, Navarrete F, Ginsberg SD, Manzanares J, Sáez-Valero J and García-Ayllón MS
Publicada:
1 ene 2016
Ahead of Print:
30 may 2016
Resumen:
Alzheimer's disease (AD) is characterized by a decrease in the enzymatic activity of the enzyme acetylcholinesterase (AChE). AChE is expressed as multiple splice variants, which may serve both cholinergic degradative functions and noncholinergic functions unrelated with their capacity to hydrolyze acetylcholine. We have recently demonstrated that a prominent pool of enzymatically inactive AChE protein exists in the AD brain. In this study, we analyzed protein and transcript levels of individual AChE variants in human frontal cortex from AD patients by western blot analysis using specific anti-AChE antibodies and by quantitative real-time PCR (qRT-PCR). We found similar protein and mRNA levels of the major cholinergic "tailed"-variant (AChE-T) and the anchoring subunit, proline-rich membrane anchor (PRiMA-1) in frontal cortex obtained from AD patients and non-demented controls. Interestingly, we found an increase in the protein and transcript levels of the non-cholinergic " readthrough" AChE (AChE-R) variants in AD patients compared to controls. Similar increases were detected by western blot using an antibody raised against the specific N-terminal domain, exclusive of alternative N-extended variants of AChE (N-AChE). In accordance with a subset of AChE-R monomers that display amphiphilic properties that are upregulated in the AD brain, we demonstrate that the increase of N-AChE species is due, at least in part, to N-AChE-R variants. In conclusion, we demonstrate selective alterations in specific AChE variants in AD cortex, with no correlation in enzymatic activity. Therefore, differential expression of AChE variants in AD may reflect changes in the pathophysiological role of AChE, independent of cholinergic impairment or its role in degrading acetylcholine.
Filiaciones:
Campanari ML:
Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain
Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
Navarrete F:
Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain
Ginsberg SD:
Center for Dementia Research, Nathan Kline Institute, Departments of Psychiatry and Neuroscience & Physiology, New York University Langone Medical Center, Orangeburg, NY, USA
Manzanares J:
Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain
Sáez-Valero J:
Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain
Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
:
Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain
Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
Unidad de Investigación, Hospital General Universitario de Elche, FISABIO, Elche, Spain
Green Submitted, Green Accepted
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