Increased myeloperoxidase plasma levels in patients with Alzheimer's disease

Tzikas, Stergios and Schlak, Dennis and Sopova, Kateryna and Gatsiou, Aikaterini and Stakos, Dimitrios and Stamatelopoulos, Kimon and Stellos, Konstantinos and Laske, Christoph (2014) Increased myeloperoxidase plasma levels in patients with Alzheimer's disease. Journal of Alzheimer's Disease, 39 (3). pp. 557-564. ISSN 1387-2877

Abstract

BACKGROUND: Increasing evidence supports the role of cardiovascular risk factors in the development of Alzheimer's disease (AD). OBJECTIVE: In the present pilot study, we investigated plasma concentrations of myeloperoxidase (MPO) and its possible association with plasma amyloid-β (Aβ)1-42/1-40 ratio in AD patients and elderly healthy controls. METHODS: The study sample included 28 AD patients and 27 elderly individuals with a normal cognitive status as a control group. The Mini-Mental Status Examination was used to determine the global cognition. MPO, Aβ1-40, and Aβ1-42 plasma concentrations were measured by enzyme linked immunoabsorbent assays. RESULTS: AD patients showed significantly higher plasma concentrations of MPO in comparison to healthy elderly controls (AD versus healthy elderly controls (mean ± SD): 132.8 ± 114.8 ng/mL versus 55.0 ± 42.6 ng/mL; p = 0.002). MPO plasma concentrations showed a significant positive correlation in the whole sample with the presence of AD (ρ = 0.428, p < 0.001) and its stage (ρ = 0.331; p = 0.013) as well as with plasma concentrations of Aβ1-42 (ρ = 0.406; p = 0.004) and Aβ1-42/1-40 ratio (ρ = 0.354; p = 0.013). In a binary logistic regression model, plasma MPO concentrations were independently associated with the presence of AD (p = 0.014). CONCLUSION: AD patients showed significantly increased plasma levels of MPO, which could be an important molecular link between atherosclerosis and AD. Further studies should evaluate whether MPO may also be a useful biomarker and potential new treatment target in AD.