Related Experiment Video
Updated: May 13, 2026
07:28
Full- versus Sub-Regional Quantification of Amyloid-Beta Load on Mouse Brain Sections
Published on: May 19, 2022
Brain β-amyloid load approaches a plateau
Clifford R Jack1, Heather J Wiste, Timothy G Lesnick
1From the Departments of Radiology, Mayo Clinic, Rochester, MN, USA. jack.clifford@mayo.edu
Neurology
|March 1, 2013
Summary
Researchers modeled beta-amyloid (β-amyloid) accumulation using PET scans. The study identified a 15-year therapeutic window for interventions during the most rapid, linear phase of amyloid buildup.
Area of Science:
- Neuroimaging
- Biomarker Research
- Alzheimer's Disease Pathogenesis
Background:
- Beta-amyloid (β-amyloid) deposition is a hallmark of Alzheimer's disease.
- Serial amyloid positron emission tomography (PET) imaging allows for tracking β-amyloid accumulation over time.
- Understanding the temporal dynamics of β-amyloid is crucial for developing effective interventions.
Purpose of the Study:
- To develop a model for the temporal trajectory of β-amyloid accumulation using serial amyloid PET imaging.
- To identify the relationship between baseline β-amyloid levels and the rate of accumulation.
- To determine the time course of β-amyloid progression and its implications for therapeutic timing.
Main Methods:
- Utilized data from 260 participants (aged 70-92) from the Mayo Clinic Study of Aging and Mayo Alzheimer's Disease Research Center.
- Measured baseline amyloid PET-relative standardized uptake values (SUVR) and estimated annual amyloid accumulation rates.
- Employed regression models to analyze the association between baseline SUVR, accumulation rate, and covariates (age, sex, clinical group, APOE).
Main Results:
- Amyloid accumulation rates showed an inverted U-shaped relationship with baseline SUVR, peaking around SUVR 2.0 and reaching zero above SUVR 2.7.
- Integration of these findings yielded a sigmoid curve describing the relationship between amyloid PET SUVR and time.
- The estimated time to progress from SUVR 1.5 to 2.5 was approximately 15 years.
Conclusions:
- A roughly 15-year period exhibits the steepest, near-linear increase in amyloid SUVR over time.
- This interval represents a significant therapeutic window for secondary preventive interventions in Alzheimer's disease.
- Modeling temporal β-amyloid accumulation aids in identifying optimal timing for interventions.
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