UCL Mental Health Sciences Unit, Charles Bell House, London, UK.
J Alzheimers Dis. 2012;31(2):277-83. doi: 10.3233/JAD-2012-120073.
By the age of 40, virtually all patients with Down syndrome (DS) have neuropathological changes characteristic of Alzheimer's disease (AD). The aim of our study was to investigate whether the levels of superoxide dismutase enzymes (SOD), glutathione peroxidase (GPx), or their ratio could predict cognitive decline in people with DS over a 4-year period. Thirty-two adults with DS participated in a longitudinal study with SOD and GPx assays at baseline. Informants rated their functional ability and memory function at baseline and at 4 years follow-up. The more able adults with DS also completed assessments of language skills and memory, at two different time points 4 years apart. Twenty-six individuals with DS completed assessments of memory (Modified Memory Object Task, MOMT), adaptive behavior (ABAS), and receptive vocabulary (British Picture vocabulary, BPVS) at both time-points. SOD positively correlated with change on the MOMT score (r = 0.578, p = 0.015). There were no significant correlations between GPx level or SOD/GPx ratio and temporal changes in ABAS, BPVS, or MOMT scores. Our results suggest that SOD predicts memory decline over time and that these antioxidant enzymes could be a potential target for prevention of memory deterioration in adults with DS. Further research is required to test whether supplements which improve SOD function can also prevent cognitive decline. These findings may also have implications for prevention of cognitive decline in other groups which are at high risk of developing dementia, such as adults with familial AD or mild cognitive impairment.
到 40 岁时，几乎所有唐氏综合征（Down syndrome，DS）患者都有阿尔茨海默病（Alzheimer's disease，AD）的特征性神经病理学变化。我们的研究目的是调查超氧化物歧化酶（superoxide dismutase，SOD）、谷胱甘肽过氧化物酶（glutathione peroxidase，GPx）或它们的比值是否可以预测 DS 患者在 4 年内认知能力下降。32 名成年 DS 患者参与了一项纵向研究，在基线时进行了 SOD 和 GPx 检测。在基线和 4 年随访时，知情人对他们的功能能力和记忆功能进行了评分。能力更强的 DS 成年患者还在相隔 4 年的两个不同时间点完成了语言技能和记忆的评估。26 名 DS 患者在两个时间点都完成了记忆（改良记忆物体任务，Modified Memory Object Task，MOMT）、适应行为（适应性行为评定量表，Adaptive Behavior Assessment System，ABAS）和接受性词汇（英国图片词汇测试，British Picture Vocabulary Scale，BPVS）的评估。SOD 与 MOMT 评分的变化呈正相关（r = 0.578，p = 0.015）。GPx 水平或 SOD/GPx 比值与 ABAS、BPVS 或 MOMT 评分的时间变化之间均无显著相关性。我们的研究结果表明，SOD 可预测随时间推移的记忆下降，这些抗氧化酶可能是预防 DS 成年患者记忆恶化的潜在目标。需要进一步研究以测试是否能提高 SOD 功能的补充剂也能预防认知能力下降。这些发现对于预防其他痴呆高风险人群（如家族性 AD 或轻度认知障碍的成年患者）的认知能力下降也可能具有重要意义。
