Expression of the human erythrocyte glucose transporter Glut-1 in areas of sclerotic collagen in necrobiosis lipoidica.

Abstract

Glut-1 is the human erythrocyte glucose transporter which mediates facilitative transport of glucose across epithelial and endothelial barrier tissues. A primary abnormality in glucose transport and Glut-1 cell-surface content has been observed in fibroblasts from NIDDM and obese individuals. With the strong correlation between necrobiosis lipoidica and diabetes mellitus, we investigated the expression of Glut-1 in diabetic individuals with necrobiosis lipoidica (NL). A polyclonal anti-Glut-1 antibody was used with a standard immunoperoxidase technique to determine Glut-1 expression by fibroblasts in areas of sclerotic collagen from specimens taken from diabetic individuals with necrobiosis lipoidica,and non-diabetic individuals with scars and granuloma annulare (GA). Our results showed Glut-1 expression in the areas of sclerotic collagen in patients with NL, possibly contributing to insulin resistance in these tissues. Our findings raises the question as to whether abnormalities in glucose transport by fibroblasts in individuals with necrobiosis lipoidica contribute to the histopathologic changes.