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bioRxiv · 10.1101/220699

Comparing neurotransmitter metabolism in the brain of patients with symptomatic and aysmptomatic Alzheimer’s disease and healthy individuals

Snowden, S. G.·Ebshiana, A.·Hye, A.·Yang, A.·Olga, P.·Richard, O.·John, T.·Cristina, L.-Q.·Madhav, T.
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Abstract

INTRODUCTIONThree of the four treatments for Alzheimers disease are cholinesterase inhibitors targeting the pathological reduction of acetylcholine levels. Here we aimed to determine the role of other neurotransmitter pathways in AD pathology.\n\nMETHODSTissue samples were obtained from three groups, controls, AD and asymptomatic AD i.e. cognitively normal individuals that had significant AD neuropathology. Three brain areas were studied, the middle frontal gyrus (MFG) the inferior temporal gyrus (ITG) and the cerebellum.\n\nRESULTS11 of 15 measured metabolites were shown to be associated with disease. Decreases in dopamine were seen in the ASYMAD group in the MFG when compared to control and AD patients (FC=0.78, p=4.1x10-3). In AD patients changes were mainly seen in the ITGs inhibitory GABAergic system.\n\nDISCUSSIONThese results indicate that dopamine could be depleted in brains with Alzheimers pathology but intact cognition, while and imbalance of several neurotransmitters is evident in the brain of AD patients.

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Snowden, S. G., Ebshiana, A., Hye, A., Yang, A., Olga, P., Richard, O., John, T., Cristina, L.-Q., Madhav, T.. 2017-11-17. Comparing neurotransmitter metabolism in the brain of patients with symptomatic and aysmptomatic Alzheimer’s disease and healthy individuals. https://doi.org/10.1101/220699

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