engleski

CSF tau proteins phosphorylated at threonine 231 as a potential biomarker of early-stage Alzheimer's disease

Mild cognitive impairment (MCI) is a syndrome characterized by cognitive impairment without dementia, which primarily affects episodic memory. Patients with MCI often have an initial stage of Alzheimer's disease (AD). Tau protein phosphorylated at threonine 231 (pT231) has recently been proposed as a possible biological marker of early AD. In this pilot study we tested whether the measurement of pT231 in the cerebrospinal fluid (CSF) correlates with other pathological features characteristic of AD in patients with MCI. A positive answer to this question would mean that this marker could be used to detect AD in the early stage of the disease. The concentration of pT231 was determined using ELISA kits in the CSF of 34 patients with probable AD, 25 MCI patients, and 7 healthy controls. Levels of pTau231 were significantly higher in the group of AD patients than in MCI patients or healthy control. ROC curve analysis showed that pTau231 could differentiate AD patients from healthy control with a sensitivity of 73.5% and a specificity of 85.7%. The cut-off level for pTau231 (1.904 U/ml) was defined when the sum of specificity and sensitivity was maximized. About 32% of MCI patients had pTau231 levels higher than the cut-off, while the rest of MCI patients (68%) had normal pT231 levels. These data suggest that about one third of MCI patients could be defined as a high-risk group with amnestic MCI. However, a follow-up period of at minimum 5 years is necessary to determine whether these patients will actually convert to AD. In conclusion, pT231 may be a useful biological marker for AD detection in the preclinical stage of the disease.

Mild cognitive impairment; phosphorylated tau protein; early diagnosis

nije evidentirano