In the present study we examined the effect of sulfonylurea on the expression of the glucose transporter GLUT2 and the glucose phosphorylating enzyme Glucokinase (GK) in beta TC6-F7 cells; furthermore, we studied the modifications induced by sulfonylurea on glucose-responsiveness and -sensitivity. Results demonstrate that sulfonylurea increases GLUT2 and GK mRNA expression after 24 h in a dose-dependent manner. On the contrary, after 48 and 72 h a time-dependent reduction of both GLUT2 and GK mRNA. occurs. GLUT2 and GK protein expression follow the same modifications. Therefore, GLUT2 and GK are coordinately regulated by sulfonylurea, probably by a common mechanism. Glucose-induced insulin release is increased by sulfonylurea as well as glucose sensitivity. Our study suggests that short-term effect of sulfonylurea increases while long-term effect reduces the expression of glucose sensing elements. The long-term inhibitory effect on glucose sensing elements would explain the reduced insulin secretion occurring after chronic sulfonylurea treatment. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.
GLUT2 and glucokinase expression is coordinately regulated by sulfonylurea / Porzio, O; Marlier, Lnjl; Federici, M; Hribal, Ml; Magnaterra, R; Lauro, D; Fusco, A; Sesti, G; Borboni, P. - In: MOLECULAR AND CELLULAR ENDOCRINOLOGY. - ISSN 0303-7207. - 153:1-2(1999), pp. 155-161. [10.1016/S0303-7207(99)00073-8]
GLUT2 and glucokinase expression is coordinately regulated by sulfonylurea
Sesti GPenultimo
Supervision
;
1999
Abstract
In the present study we examined the effect of sulfonylurea on the expression of the glucose transporter GLUT2 and the glucose phosphorylating enzyme Glucokinase (GK) in beta TC6-F7 cells; furthermore, we studied the modifications induced by sulfonylurea on glucose-responsiveness and -sensitivity. Results demonstrate that sulfonylurea increases GLUT2 and GK mRNA expression after 24 h in a dose-dependent manner. On the contrary, after 48 and 72 h a time-dependent reduction of both GLUT2 and GK mRNA. occurs. GLUT2 and GK protein expression follow the same modifications. Therefore, GLUT2 and GK are coordinately regulated by sulfonylurea, probably by a common mechanism. Glucose-induced insulin release is increased by sulfonylurea as well as glucose sensitivity. Our study suggests that short-term effect of sulfonylurea increases while long-term effect reduces the expression of glucose sensing elements. The long-term inhibitory effect on glucose sensing elements would explain the reduced insulin secretion occurring after chronic sulfonylurea treatment. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
