학술논문

Butanol Positron Emission Tomography reveals an impaired brain to nasal turbinates pathway in aging amyloid positive subjects
Document Type
Academic Journal
Source
Fluids and Barriers of the CNS. April 2, 2024, Vol. 21 Issue 1
Subject
Brain
Nervous system diseases
PET imaging
Alzheimer's disease
Tracers (Biology)
Language
English
ISSN
2045-8118
Abstract
Background Reduced clearance of cerebrospinal fluid (CSF) has been suggested as a pathological feature of Alzheimer's disease (AD). With extensive documentation in non-human mammals and contradictory human neuroimaging data it remains unknown whether the nasal mucosa is a CSF drainage site in humans. Here, we used dynamic PET with [1-.sup.11C]-Butanol, a highly permeable radiotracer with no appreciable brain binding, to test the hypothesis that tracer drainage from the nasal pathway reflects CSF drainage from brain. As a test of the hypothesis, we examined whether brain and nasal fluid drainage times were correlated and affected by brain amyloid. Methods 24 cognitively normal subjects ([greater than or equal to] 65 years) were dynamically PET imaged for 60 min. using [1-.sup.11C]-Butanol. Imaging with either [.sup.11C]-PiB or [.sup.18F]-FBB identified 8 amyloid PET positive (A[beta]+) and 16 A[beta]- subjects. MRI-determined regions of interest (ROI) included: the carotid artery, the lateral orbitofrontal (LOF) brain, the cribriform plate, and an All-turbinate region comprised of the superior, middle, and inferior turbinates. The bilateral temporalis muscle and jugular veins served as control regions. Regional time-activity were used to model tracer influx, egress, and AUC. Results LOF and All-turbinate 60 min AUC were positively associated, thus suggesting a connection between the brain and the nose. Further, the A[beta]+ subgroup demonstrated impaired tracer kinetics, marked by reduced tracer influx and slower egress. Conclusion The data show that tracer kinetics for brain and nasal turbinates are related to each other and both reflect the amyloid status of the brain. As such, these data add to evidence that the nasal pathway is a potential CSF drainage site in humans. These data warrant further investigation of brain and nasal contributions to protein clearance in neurodegenerative disease. Keywords: Dynamic PET, [1-11 C]-Butanol, CSF clearance, Glymphatic, Amyloid PET, Nasal turbinates, Cribriform plate, Alzheimer Disease, Aging
Author(s): Neel H. Mehta[sup.1,2], Xiuyuan Wang[sup.1], Samantha A. Keil[sup.1], Ke Xi[sup.1], Liangdong Zhou[sup.1], Kevin Lee[sup.1,10], Wanbin Tan[sup.1], Edward Spector[sup.1,12], Amirhossein Goldan[sup.1,9], James Kelly[sup.3], Nicolas A. Karakatsanis[sup.9], P. David Mozley[sup.1,4], Sadek [...]