Mufson E J, Chen E Y, Cochran E J, Beckett L A, Bennett D A, Kordower J H
Department of Neurological Sciences, Rush Alzheimer's Disease Center, Chicago, Illinois, 60612, USA.
Exp Neurol. 1999 Aug;158(2):469-90. doi: 10.1006/exnr.1999.7086.
The deposition of beta-amyloid within the entorhinal cortex (EC) may play a key role in the development of mild cognitive impairment (MCI) in the elderly. To examine the relationship of beta-amyloid deposition to MCI, EC tissue immunostained for this protein was quantitated from a cohort of aged Catholic religious clergy with a clinical diagnosis of MCI and compared to those with no cognitive impairment (NCI) and Alzheimer's disease (AD). beta-amyloid staining was seen in 12 of the 20 NCI, in 10 of 12 MCI, and in all 12 AD cases within the EC. beta-amyloid immunoreactivity displayed two patterns within the EC: (1) a crescent-shaped band within layers 3-4 or (2) bilaminar staining mainly within layers 2-3 and 5-6. Ten cases failed to display any detectable beta-amyloid imunoreactivity. Despite the heterogeneity of beta-amyloid loads within the clinical groups, decomposing an analysis of variance revealed a significant difference across groups in mean beta-amyloid load within the EC based upon a linear trend analysis. Multiple comparisons testing revealed that NCI individuals had a significantly lower mean beta-amyloid load (1.32) than AD individuals (4.55). The MCI individuals had a mean intermediate (2.60) load between NCI and AD, but not statistically distinguishable from the mean for either NCI or AD. Spearman rank correlation showed a trend for decreasing MMSE with increasing amyloid load that failed to reach statistical significance. Since many NCI cases displayed beta-amyloid loads equal to or greater than that seen in some MCI and some AD cases, it is mostly likely that deposition of this protein is not the sole pathogenic event underlying cognitive impairment in the elderly.
β-淀粉样蛋白在海马旁回皮质（EC）内的沉积可能在老年人轻度认知障碍（MCI）的发展中起关键作用。为了研究β-淀粉样蛋白沉积与MCI的关系，对一组临床诊断为MCI的老年天主教神职人员的EC组织进行该蛋白的免疫染色定量，并与无认知障碍（NCI）和阿尔茨海默病（AD）患者进行比较。在20例NCI患者中有12例、12例MCI患者中有10例以及所有12例AD患者的EC内均可见β-淀粉样蛋白染色。β-淀粉样蛋白免疫反应性在EC内呈现两种模式：（1）3-4层内的新月形带或（2）主要在2-3层和5-6层内的双层染色。10例患者未显示任何可检测到的β-淀粉样蛋白免疫反应性。尽管临床组内β-淀粉样蛋白负荷存在异质性，但基于线性趋势分析的方差分解显示，EC内平均β-淀粉样蛋白负荷在各组间存在显著差异。多重比较检验显示，NCI个体的平均β-淀粉样蛋白负荷（1.32）显著低于AD个体（4.55）。MCI个体的平均负荷处于NCI和AD之间（2.60），但与NCI或AD的平均值在统计学上无显著差异。Spearman等级相关性显示，随着淀粉样蛋白负荷增加，MMSE有下降趋势，但未达到统计学显著性。由于许多NCI病例的β-淀粉样蛋白负荷等于或高于一些MCI和一些AD病例，很可能该蛋白的沉积不是老年人认知障碍的唯一致病事件。
