DECREASED ERYTHROCYTE-MEMBRANE FLUIDITY IN POORLY CONTROLLED IDDM - INFLUENCE OF KETONE-BODIES

OBJECTIVE-To examine the factors that might alter the fluidity of erythrocyte membrane in insulin-dependent diabetes mellitus (IDDM) patients. RESEARCH DESIGN AND METHODS-The subjects were 10 healthy men and 30 IDDM men: 10 with good blood glucose (BG) control (HbA(1c) 5.88 +/- 0.60% [mean +/- SD]), 10 with poor BG control (HbA(1c) 9.48 +/- 1.05%), and 10 with poor BG control and mild to moderate diabetic ketoacidosis (DKA) (HbA(1c) 9.12 +/- 2.25%, strongly positive ketonuria 3+ and elevated plasma beta-hydroxybutyrate). Erythrocyte membrane fluidity was determined by fluorescence polarization using 6-(9-anthroyloxy) stearic acid as fluorescent probe. RESULTS-Membrane fluidity was normal in the diabetic patients with good BG control but significantly lower in the two groups of patients with poor BG control than in the healthy subjects (P < 0.01). The membrane fluidity in the poor BG control groups was also lower in the patients with DKA than in those without DKA (P < 0.01). CONCLUSIONS-The factors that most influence membrane fluidity in IDDM patients appear to be hyperglycemia and ketone bodies.