[2014-1] Mizoi et al., Clin. Chim. Acta 430, 150-155 (2014)

BACKGROUND: We found previously that the amyloid b40/42 (Ab_40/42) ratio and the level of protein-conjugated acrolein (PC-Acro) in plasma were increased in mild cognitive impairment (MCI) and Alzheimer’s disease (AD) subjects. We determined whether MCI and AD subjects can be differentiated based on the levels of Ab₄₀, Ab₄₂, and PC-Acro in cerebrospinal fluid (CSF).

METHODS: Ab₄₀, Ab₄₂, PC-Acro, Tau and phosphorylated Tau in CSF were measured by ELISA.

RESULTS: Median values of Ab₄₀, Ab₄₀/PC-Acro and Ab_40/42 in CSF were significantly lower in 54 AD subjects than those in 40 MCI subjects. Severity of VOI (volume of interest) atrophy was most intensely correlated with the decrease in Ab₄₀/PC-Acro and then that in Ab₄₀ and Ab₄₂/PC-Acro. MMSE was most intensely correlated with the decrease in Ab₄₂ and Ab₄₀, and then that in Ab₄₂/PC-Acro and Ab₄₀/PC-Acro.

CONCLUSION: A decrease in Ab₄₀/PC-Acro in CSF is well correlated with brain damage, and a decrease in Ab₄₂ and Ab₄₀ is well correlated with cognitive ability. Measurement of PC-Acro together with Ab₄₀ and Ab₄₂ provides a more precise evaluation of severity of AD subjects.