Ceftezole, a cephem antibiotic, is an alpha-glucosidase inhibitor with in vivo anti-diabetic activity

Using a high throughput-compatible assay to screen for potential alpha-glucosidase inhibitors, we found that the beta-lactam Antibiotic ceftezole exhibited potent alpha-glucosidase inhibitory activity. In in vitro alpha-glucosidase assays, ceftezole was shown to be a reversible, non-competitive inhibitor of yeast alpha-glucosidase with a Ki value of 5.78 x 10(-7) M when the enzyme mixture was pretreated with ceftezole. Using an in vivo streptozotocin-induced mouse model, we confirmed that blood glucose levels decreased by 30% 20 min after ceftezole treatment (10 mg/kg/day). Expression levels of glycogen synthase kinase-3, peroxisome proliferator-activated receptor-gamma, and uncoupling protein-3 mRNA were also slightly decreased compared to controls following ceftezole treatment. Taken together, these in vivo and in vitro results suggest that ceftezole may be a clinically useful anti-diabetic compound.