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Updated: Feb 3, 2026

Determination of Plasma Membrane Partitioning for Peripherally-associated Proteins
Published on: June 15, 2018
Aging and APOE-ε4 are determinative factors of plasma Aβ42 levels
Takumi Nakamura1, Takeshi Kawarabayashi1, Yusuke Seino1
1Department of Neurology Hrosaki University Graduate School of Medicine 5 Zaifu-cho Hirosaki 037-8562 Japan.
Objective:
The aim of this study was to confirm determinative factors for plasma Aβ and its association with cognitive function.
Methods:
Fasting plasma Aβ40 and Aβ42 levels were measured by ELISA in 1019 participants in the Iwaki Health Promotion Project. The relationships between plasma Aβ and health-related items, including physical characteristics, cognitive function tests, blood chemistry, and APOE-ε4 genotype were analyzed.
Results:
The plasma levels of Aβ40 and Aβ42, and Aβ40/42 ratio were found to significantly increase with aging. The age-dependent increase in Aβ42 level was significantly suppressed by APOE-ε4. Renal function was an associated factor for the plasma Aβ40 level. The plasma Aβ42 level and Aβ40/42 ratio correlated with cognitive function.
Interpretation:
Age and APOE-ε4 are major determinative factors of plasma levels of Aβ42 and the Aβ40/42 ratio. These factors are critical adjustment factors for the usage of plasma Aβ as a biomarker of central nervous system amyloidosis.
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