RecruitingNot ApplicableNCT05911178

Impact of Microglial Activation on Synaptic Density in Alzheimer's Disease

Sponsor

Centre Hospitalier St Anne

Enrollment

90 participants

Start Date

Oct 18, 2023

Study Type

INTERVENTIONAL

Conditions

Alzheimer Disease

Summary

This study aims to analyse, in vivo, the interplay between microglial activation and tau pathology in Alzheimer's disease (AD) using \[18F\]-DPA-714 and \[18F\]-Ro948 tracers by Position Emission Tomography (PET), and their consequences on synaptic density using \[11C\]-UCB-J, a recent PET radioligand. By coupling advanced neuroimaging techniques in AD patients, while comparing them to controls, we will be able to study, for the first time in humans, the interaction between neuroinflammation, tau pathology, synaptic density, and their impact on AD progression. Joint analyses of peripheral immune biomarkers, carried out as a secondary objective, will further aim at defining peripheral correlates of this interplay. Overall, we aim to refine AD subgroup classification in order to improve and to refine the design of new therapeutic trials.

Eligibility

Min Age: 18 Years

Inclusion Criteria14

Adult (older than 18 years)
Women old enough to procreate under effective contraception
Signed consent
Absence of general or systemic disorders that may interfere with cognition.
Progressive amnestic syndrome, associated or not with other cognitive impairments,
CDR = 0.5 or 1
Absence of general or systemic disorders that may interfere with cognition or PET imaging analysis,
Absence of brain lesions as determined by MRI carried out within the framework of usual care.
Presence of CSF biomarkers profile suggestive of AD
absence of subjective problems with memory and normal scores on the MMSE (MMSE \> 27) with no more than one word missing.
older than 50 years old.
Scores on the Free and Cued Selective Reminding Test (FCSRT) of \>25 for free recall and \>44 for total recall.
absence of general or systemic disorders that may interfere with cognition at follow-up.
Controls will be matched to AD patients for age and education level.

Exclusion Criteria11

Subject with a psychiatric evolutionary and/or poorly checked pathology (left to the judgement of the investigator).
Subject with a grave, severe or unstable pathology (left to the judgement of the investigator) the nature of which can interfere with the variables of evaluation.
Current auto-immune disease
Subject presenting contraindications to the 3T MRI
Known or supposed histories (≤5 years) of severe alcoholism or misuse of drugs
Vascular, inflammatory or expansive, visible lesion in the MRI which can interfere on the criteria of diagnosis.
No health insurance
Pregnant, breast-feeding woman or planning a pregnancy in two years of follow-up.
Diagnosis or history of other possible etiology of dementia, including but not limited to other neurodegenerative disorders.
Person placed under the protection of justice
Patient under guardianship or curatorship

Interventions

RADIATION[11C]-UCB-J

PET tracer binding to "SV2A" protein, used to study synaptic vesicle density.

RADIATION[18F]-DPA-714

PET tracer binding to "TSPO" protein, used to study microglial activation.

RADIATION[18F]-RO-948

PET tracer binding to "tau" protein, used to study the topography of tau deposition.

RADIATION[11C]-PiB

PET tracer binding to Aβ40 and Aβ42 fibrils and insoluble plaques containing the aforementioned Aß peptides, used to study the topography of amyloid deposition.