Abstract
Cathinone, the main bioactive alkaloid of Catha edulis (khat), slightly increased the blood sugar levels of healthy animals, while its effect on blood sugar levels of diabetic animals has not yet been reported. This study investigated the in vitro inhibition of cathinone on α-amylase and α-glucosidase as well as its in vivo glycemic effects in diabetes-induced rats. Rats were fed on a high fat diet for five weeks, which then intraperitoneally injected with streptozotocin (30 mg/kg). Diabetic rats were distributed randomly into diabetic control (DC, n = 5), 10 mg/kg glibenclamide-treated group (DG, n = 5), and 1.6 mg/kg cathinone-treated group (CAD, n = 5). Additional healthy untreated rats (n = 5) served as a nondiabetic negative control group. Throughout the experiment, fasting blood sugar (FBS), caloric intake and body weight were recorded weekly. By the 28th day of treatment, rats were euthanized to obtain blood samples and pancreases. The results demonstrated that cathinone exerted a significantly less potent in vitro inhibition than α-acarbose against α-amylase and α-glucosidase. As compared to diabetic control group, cathinone significantly increased FBS of diabetic rats, while insulin levels of diabetic rats significantly decreased. In conclusion, cathinone was unable to induce a substantial in vitro inhibition on α-amylase and α-glucosidase, while it exacerbated the hyperglycemia of diabetes-induced rats.