THE EFFECT OF GLUCOSE AND INSULIN UPON HUMAN ERYTHROCYTE MEMBRANE ATPases

MIHAELA STĂNESCU*, GABRIELA ZAMFIRESCU**, DANA IORDĂCHESCU***

*Division of Cell Biology, Department of Animal Biology, Faculty of Biology, University of Bucharest, 91-95 Splaiul Independentei, Bucharest
**National Institute of Recovery, Physical Medicine and Blaneoclimatology, 11A Ion Mihalache Blvd, Bucharest
***Department of Biochemistry, Faculty of Biology, University of Bucharest, 91-95, Splaiul Independentei, 76201 Bucharest

Abstract. Elevated level of glucose in the blood is known to cause membrane damage. By using human erythrocytes the present study has examined the changes that are induced by hyperglycemia in the absence or presence of a different amount of insulin on the activity of membrane ATPases. Normal human erythrocytes were incubated with varying concentrations of glucose at 37 °C for 72 h, in the presence or absence of 10 mIU/l or 200 mIU/l insulin. Erythrocytes incubated with an elevated level of glucose showed a modified electrophoretic profile of membrane proteins, a significantly increased protein glycation and reduced ATPases activity. A significantly positive correlation was observed between the extent of protein glycation and the activity of membrane ATPases. 200 mIU/l insulin restores the electrophoretic profile of membrane protein, reduces the level of protein glycation and increases the enzymatic activity to of control value.

Full text: PDF