Immunohistochemical detection of hepatic GM1 and GM2 gangliosides in streptozotocin-induced diabetic rats

Abstract

This study was undertaken to investigate the consequences of diabetes on the expression of GM1 and GM2 gangliosides in rat liver. Experimental diabetes was induced by treatment with Streptozotocin (STZ) in adult male Sprague-Dawley rats. Two-dimensional thin-layer chromatography of total ganglioside preparations of liver tissues from STZ-induced diabetic rats showed an increased amount of GM1, while GM2 could not be detected. In order to identify ganglioside expression and corroborate possible changes after short-term diabetes (3 weeks), frozen sections of the liver were stained with two monoclonal antibodies, GMB16 (GM1 specific) and GMB28 (GM2 specific). Although both antibodies were capable of immunostaining the diabetic hepatocytes at the cell surface, strong reactivity was observed for GMB16 while GMB28 developed only a weak labeling. The hepatic ganglioside expression of insulin-stabilized diabetic rats was restored, resembling the profile of normal rats. The important alterations in the expression of GM1 and GM2 gangliosides in short-term diabetes were accompanied by certain microscopic changes in the liver, so that these gangliosides may be useful markers in the detection of early liver diabetic complications.