In vitro inhibition of human erythrocyte hexokinase by various hyperglycemic drugs.

Hemolysis is the red blood cell abnormality most often associated with adverse effect of drug therapy. Drug-induced or drug-associated hyperglycemia could decrease the activity of hexokinase. The aim of this study was to investigate the inhibitory effects of some commonly used drugs that have hyperglycemic side effect on the human erythrocyte hexokinase enzyme in vitro. Hexokinase was purified from human erythrocytes using sequential chromatography, with a specific activity of 0.96 ± 0.18 U/g hemoglobin, and assayed in the presence of selected drugs that have hyperglycemic side effect. The IC50 were determined from the regression analysis graph. Correlation analysis showed that there was positive correlation between the hyperglycemic side effect of some of the tested drugs and decrease of hexokinase activity. This suggests that, at least in part, these drugs exert their hyperglycemic effect by inhibiting glucose phosphorylation by the hexokinase, which consequently causes the glucose accumulation.