Regulation of glucose transporter 1 (GLUT1) gene expression by epidermal growth factor in bovine corneal endothelial cells

The regulation mechanism of glucose transporter 1 (GLUT1) gene expression was investigated in cultured bovine corneal endothelial cells. Epidermal growth factor (EGF) stimulated both GLUT1 mRNA expression and cell proliferation. Fetal bovine serum, in contrast, stimulated cell proliferation but did not increase GLUT1 mRNA. IGF-I, hyaluronic acid or fibronectin did not stimulate GLUT1 gene expression. These results suggest that GLUT1 gene expression is controlled, at least in part, by EGF and is related to neither cell proliferation, cell motility nor cell adhesion regulation. The EGF signal was transduced through a pathway including protein kinase C. GLUT1 is reported to work as a water transporter, and so EGF can be considered as one of the possible agents which stimulate water transport activity through the corneal endothelial cells. EGF could be useful in the therapy of corneal edema caused by endothelial dysfunction.