Decreased plasmatic spermidine and increased spermine in mild cognitive impairment and Alzheimer’s disease patients

Abstract Background Current evidence suggests that upregulation of polyamines system plays a role both in cognitive deficit and synaptic loss observed in Alzheimer’s disease (AD). Objective The aim of this study was to determine the plasmatic concentration of polyamines in mild cognitive impairment (MCI) and AD patients in comparison with healthy controls (HC). Methods Plasmatic polyamines were quantified using the AbsoluteIDQ® p180 and liquid chromatography coupled to tandem mass spectrometry (LC/MS-MS). Results The study group comprised 34 AD patients, 20 MCI and 25 HC. All individuals were followed for 4 years. During this period 8 amnestic MCI patients (40% of the MCI sample at baseline) converted to AD. Spermidine level was lower in both patient groups (AD; MCI) compared to HC (p = 0.007). Plasma levels of spermine were higher in the MCI group (p < 0.001), but decreased in the sub-sample of MCI patients who converted to AD (p = 0.043). No statistically significant differences were found in ornithine and putrescine levels (p = 0.056 and p = 0.126, respectively). Discussion Our results suggest dynamic changes in the expression of polyamines in the MCI-AD continuum.

研究背景：现有证据表明，多胺(Polyamines)系统的上调在阿尔茨海默病(AD)患者所出现的认知缺损与突触丢失过程中均发挥了作用。
研究目的：本研究旨在对比轻度认知障碍(MCI)患者、AD患者与健康对照(HC)的血浆多胺浓度水平。
研究方法：本研究采用AbsoluteIDQ® p180试剂盒结合液相色谱-串联质谱(LC/MS-MS)对血浆多胺进行定量检测。
研究结果：本研究共纳入34例AD患者、20例MCI患者及25例健康对照，所有受试者均完成了4年的随访。随访期间，8例遗忘型MCI患者（占基线时MCI样本的40%）进展为AD。与健康对照相比，AD组与MCI组患者的血浆亚精胺(Spermidine)水平均显著降低（p=0.007）。MCI组患者的血浆精胺(Spermine)水平高于健康对照（p<0.001），但在进展为AD的MCI亚组患者中，精胺水平出现下降（p=0.043）。鸟氨酸(Ornithine)与腐胺(Putrescine)的血浆水平未观察到统计学显著性差异（分别为p=0.056、p=0.126）。
讨论：本研究结果提示，在MCI至AD的疾病连续进程中，多胺的表达存在动态变化。