Cortical cholinergic dysfunction correlates with microglial activation in the substantia innominata in REM sleep behavior disorder.

In vivo PET studies in patients with isolated REM sleep behavior disorder (iRBD) have shown presence of neuroinflammation (microglial activation) in the substantia nigra, and reduced cortical acetylcholinesterase activity, suggestive of cholinergic dysfunction, that was more widespread in patients with poorer cognitive performances. This study aimed to explore whether reduced cortical acetylcholinesterase activity in iRBD is linked to microglial activation in the substantia innominata (SI), the major source of cholinergic input to the cortex. We used 11C(R)-PK11195 and 11C-Donepezil PET to assess levels of activated microglia and cholinergic function, respectively, in 19 iRBD patients. 11C(R)-PK11195 binding potential (BPND) and 11C-Donepezil distribution volume ratio (DVR) values were correlated using the Pearson statistic. We found that a lower cortical 11C-Donepezil DVR correlated with a higher 11C(R)-PK11195 BPND in the SI (r = -0.48, p = 0.04). At a voxel level, the strongest negative correlations were found in the frontal and temporal lobes. Our results suggest that reduced cortical acetylcholinesterase activity observed in our iRBD patients could be linked to the occurrence of neuroinflammation in the SI. Early modulation of microglial activation might therefore preserve cortical cholinergic functions in these patients. Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.

Citation

Kristian Stær, Alex Iranzo, Morten G Stokholm, Karen Østergaard, Mónica Serradell, Marit Otto, Kristina B Svendsen, Alicia Garrido, Dolores Vilas, Joan Santamaria, Arne Møller, Carles Gaig, David J Brooks, Per Borghammer, Eduardo Tolosa, Nicola Pavese. Cortical cholinergic dysfunction correlates with microglial activation in the substantia innominata in REM sleep behavior disorder. Parkinsonism & related disorders. 2020 Dec;81:89-93

Mesh Tags

Substances

PMID: 33099132

search → result