Changes in phospholipid composition of blood cell membranes (erythrocyte, platelet, and polymorphonuclear) in different types of diabetes--clinical and biological correlations.

A variety of disorders of erythrocyte, platelet, and polymorphonuclear leukocyte (PMN) functions have been described in diabetes. The phospholipid composition of erythrocyte, platelet, and PMN membranes from controls and from type I and II diabetics was investigated in this study. Phospholipids were determined by densitometry using the molybdenum blue reagent. In diabetics, the relative abundance of phosphatidylethanolamine (PE) increased in all cell types studied, whereas those of sphingomyelin (Sph) and phosphatidylcholine (PC) were decreased in platelets and PMN. The percentage of phosphatidylserine (PS) was reduced in erythrocytes but increased in platelets. The level of Sph in PMN was significantly lower in type I than in type II diabetics. Moreover, the longer the duration of diabetes and the poorer the metabolic control, the greater the decrease in Sph. Rheological parameters, which reflect the behavior of red blood cells (RBC), were correlated with the alteration in PE/PS ratio in these cells.