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bioRxiv · 10.1101/2022.03.09.483594

Altered excitatory and inhibitory neuronal subpopulation parameters are distinctly associated with tau and amyloid in Alzheimer's disease

Ranasinghe, K.·Verma, P.·Cai, C.·Xie, X.·Kudo, K.·Gao, X.·Lerner, H.·Mizuiri, D.·Strom, A.·Iaccarino, L.·La Joie, R.·Miller, B. L.·Gorno-Tempini, M. L.·Rankin, K. P.·Jagust, W. J.·Vossel, K.·Rabinovici, G.·Raj, A.·Nagarajan, S.
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Abstract

BackgroundNeuronal and circuit level abnormalities of excitation and inhibition are shown to be associated with tau and amyloid-beta (A{beta}) in preclinical models of Alzheimers disease (AD). These relationships remain poorly understood in patients with AD. MethodsUsing empirical spectra from magnetoencephalography (MEG) and computational modeling (neural mass model; NMM) we examined excitatory and inhibitory parameters of neuronal subpopulations and investigated their specific associations to regional tau and A{beta}, measured by positron emission tomography (PET), in patients with AD. ResultsPatients with AD showed abnormal excitatory and inhibitory time-constants and neural gains compared to age-matched controls. Increased excitatory time-constants distinctly correlated with higher tau depositions while increased inhibitory time-constants distinctly correlated with higher A{beta} depositions. ConclusionsOur results provide critical insights about potential mechanistic links between abnormal neural oscillations and cellular correlates of impaired excitatory and inhibitory synaptic functions associated with tau and A{beta} in patients with AD. FundingThis study was supported by the National Institutes of Health grants: K08AG058749 (KGR), F32AG050434-01A1 (KGR), K23 AG038357 (KAV), P50 AG023501, P01 AG19724 (BLM), P50-AG023501 (BLM & GDR), R01 AG045611 (GDR); AG034570, AG062542 (WJ); NS100440 (SSN), DC176960 (SSN), DC017091 (SSN), AG062196 (SSN); a grant from John Douglas French Alzheimers Foundation (KAV); grants from Larry L. Hillblom Foundation: 2015-A-034-FEL and (KGR); 2019-A-013-SUP (KGR); a grant from the Alzheimers Association: (PCTRB-13-288476) (KAV), and made possible by Part the CloudTM, (ETAC-09-133596); a grant from Tau Consortium (GDR & WJJ), and a gift from the S. D. Bechtel Jr. Foundation.

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Ranasinghe, K., Verma, P., Cai, C., Xie, X., Kudo, K., Gao, X., Lerner, H., Mizuiri, D., Strom, A., Iaccarino, L., La Joie, R., Miller, B. L., Gorno-Tempini, M. L., Rankin, K. P., Jagust, W. J., Vossel, K., Rabinovici, G., Raj, A., Nagarajan, S.. 2022-03-10. Altered excitatory and inhibitory neuronal subpopulation parameters are distinctly associated with tau and amyloid in Alzheimer's disease. https://doi.org/10.1101/2022.03.09.483594

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