Low-density platelet populations demonstrate low in vivo activity in sporadic Alzheimer disease
2012 (English)In: Platelets, ISSN 0953-7104, E-ISSN 1369-1635, Vol. 23, no 2, 116-120 p.Article in journal (Refereed) Published
Platelets contain a substantial quantity of amyloid-precursor protein (APP) and β-amyloid. However, despite the large importance of APP and β-amyloid to dementia, little is known about platelets in sporadic Alzheimer dementia (AD). Furthermore, platelet heterogeneity influences human pathology and has been described to affect the progression of AD. This study investigated AD platelets with respect to density diversity and in vivo activity associated with density sub-fractions. We included 39 AD patients and used, as controls, 22 elderly individuals without apparent memory disorder. A continuous Percoll™ gradient covering the density span 1.04–1.09 kg/l provided the basis to divide platelets of whole blood into density fractions (n = 16). All platelet populations were evaluated accordingly. Platelet counts were determined electronically. A flow-cytometer was put to use to measure surface-bound fibrinogen as a measure of platelet in vivo activity. Samples obtained from patients diagnosed with sporadic AD contained platelets (fractions numbers 4–16) that circulated with significantly less surface-bound fibrinogen, i.e., their platelet activation in vivo was reduced, compared with controls. In particular, highly significant differences (p < 0.001) were obtained for the six less dense platelet populations (fractions numbers 11–16) when comparing sporadic AD with controls. In contrast, the densest AD platelets in fractions numbers 1–3 did not differ significantly from control cells with respect to in vivo platelet-bound fibrinogen. It is concluded that sporadic AD is characterized by lower density platelet populations that, while circulating, exhibited reduced activation. The clinical significance of this finding is unclear but these results suggest the importance of platelet heterogeneity in dementia as a topic for further investigation.
Place, publisher, year, edition, pages
London: Informa Healthcare, 2012. Vol. 23, no 2, 116-120 p.
Fibrinogen, dementia, platelet heterogeneity, platelet in vivo activation, sporadic Alzheimer disease
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-74251DOI: 10.3109/09537104.2011.593654ISI: 000300047700004OAI: oai:DiVA.org:liu-74251DiVA: diva2:481785
funding agencies|Swedish Board for Health and Welfare||The Ahlens Foundation||Gun and Bertil Stones Foundation||Magn. Bergvalls Foundation||Petrus och Augusta Hedlunds foundation||Pfizer AB||Swedish Alzheimer Foundation||Stiftelsen for Gamla Tjanarinnor||2012-01-222012-01-222012-03-02