Is the increase in glycosylated hemoglobin (HbA 1 ) responsible for the erythrocyte deformability decrease in diabetics? 1

Abstract

This study was undertaken to assess the role of glycosylated hemoglobins (HbA₁) in the reduced erythrocyte deformability of diabetic patients. Filtration tests were carried out on washed RBC suspensions and data show no correlation between the relative filtration time (RFT) and cell HbA₁ concentration. Conversely, a strong correlation was found between RFT an cell HbA₀ concentration. On the other hand, viscometric assays were performed on hemoglobin solutions after HbA₁a+b, HbA₁c and HbA₀ were separated by chromatography. Glycosylated hemoglobin fractions show intrinsic viscosities about 2.5 fold that of non glycosylated fractions (HbA₁a+b : {η} = 7.12 ml/g, HbA₁c : {η} = 7.63 ml/g, HbA₀ : {η} = 3.07 ml/g). In conclusion, our data suggest that an increase in HbA₁ induces an increase in RBC internal viscosity but seems to have no influence on RBC deformability when tested with a 5 µm filter.