We previously showed that degradation of the endothelial glycocalyx contributes to peripheral insulin resistance. In type II diabetes patients, endothelial glycocalyx dimensions in the sublingual microcirculation were recently found to be decreased compared to healthy subjects, but to be improved by sulodexide, a mixture of glycosaminoglycan components present in the endothelial glycocalyx (Broekhuizen et al. 2010). In the current study we tested if sulodexide treatment could ameliorate the deterioration in whole-body glucose tolerance induced by a high-fat diet (HFD) in mice.