Erythrocyte metabolic alterations in type I diabetes: relationship to metabolic control.

Erythrocytes from young type I diabetic patients (n = 11), incubated in their plasma in anaerobic conditions, exhibited higher glucose consumption than cells from controls (n = 11). This increased metabolic activity is believed to reflect erythrocyte alterations dependent on the degree of metabolic control, as glucose consumption was significantly correlated to glycosylated haemoglobin (HbA1) and to glucose levels (P < 0.05 and P < 0.01 respectively). Red cell hexokinase (HK) and pyruvate kinase (PK) activities were similar in both groups whereas phosphofructokinase (PFK) activity was slightly higher in patients' cells (P < 0.05). No difference was found between patients and controls for red cell ATP and 2.3 diphosphoglycerate (2.3 DPG) levels. However, the concentrations of these glycolytic products seem also closely related to the glucose homeostasis in diabetes. Indeed, within the diabetic group, ATP levels showed a negative relationship with glucose level (P < 0.05) and 2.3 DPG a positive relationship with HbA1 (P < 0.05). In conclusion, higher glycolytic activity is present in young diabetic red cells. This activity as well as ATP and 2.3 DPG levels are related to the degree of short- or long-term diabetic control. These findings stress the importance of a careful metabolic control to avoid haematological disturbances.