Reduced circulating angiogenic cells in Alzheimer disease.

Abstract

Neurovascular dysfunction and senescent endothelium contribute to the progression of Alzheimer disease (AD). Circulating angiogenic cells (CACs), such as endothelial progenitor cells (EPCs), provide a cellular reservoir for the endothelial replacement. To study the involvement of CACs in AD pathogenesis, we investigated the levels of CACs in patients with AD. Consecutive patients with newly diagnosed AD (n = 55), patients with non-AD neurodegenerative diseases (n = 37), and nondemented risk factor control subjects (RF control, n = 55 and 37) were enrolled after matching for age, sex, and Framingham risk score. Peripheral blood samples were taken, and EPC colony-forming units (CFU-EPC) were cultured and counted. The patients with AD had significantly lower CFU-EPC than the RF controls. In the patients with AD, a lower CFU-EPC was independently associated with either a lower Mini-Mental State Examination score or a higher Clinical Dementia Rating scale score, indicating a greater reduction in CFU-EPC in advanced AD. Patients with non-AD neurodegenerative diseases did not show a significant decrease in CFU-EPC levels. Our results indicate that patients with Alzheimer disease (AD) have reduced circulating angiogenic cells, suggesting that an abnormal capacity to regenerate endothelium is associated with AD.