Increased Platelet and Erythrocyte External Cell Membrane Phosphatidylserine in Type 1 Diabetes and Microalbuminuria
- 1Department of Diabetes and Endocrinology, Diabetes Care Centre, South Tees Acute Hospitals NHS Trust, Middlesbrough
- 2Department of Medicine, School of Clinical Medical Sciences, University of Newcastle upon Tyne, Newcastle upon Tyne, U.K.
The cosegregation of traditional risk factors, such as smoking, hypertension, dyslipidemia, and hyperglycemia, per se do not fully account for the excessive cardiovascular risk in diabetes (1,2), thus suggesting that there are other contributory factors. Diabetes is associated with several defects of coagulation and fibrinolysis that predispose to a thrombogenic tendency (3,4,5). Phospholipids are distributed asymmetrically between the inner and outer leaflets of the normal cell membrane lipid bilayer (6), with the cholinephospholipids (phosphatidylcholine and phosphatidylsphingomyelin) predominantly in the external leaflet and the aminophospholipids (phosphatidylserine [PS] and phosphatidylethanolamine) located internally. This equilibrium can be disrupted by activation of the calcium-dependent scramblase enzyme (6). PS is a potent activator of thrombin and other clotting factors (6), thus promoting a procoagulant environment that may increase the risk of cardiovascular disease. Therefore, we investigated whether there is an increase in PS in the outer leaflet of the lipid bilayer of erythrocyte and platelet cell membranes in type 1 diabetic patients and whether this is associated with changes in the appearance of scramblase.
Consent for the study was obtained from 13 healthy control …