Effects of 95% ethanol extract of Aquilaria sinensis leaves on hyperglycemia in diabetic db/db mice

The leaves of Aquilaria sinensis (Lour.) Gilg have been used in folk medicine for the treatment of diabetes in Guangdong Province, China. In this study, effects of ethanol extract of Aquilaria sinensis leaves on hyperglycemia were investigated in diabetic db/db mice. After 4 weeks of administration, the 95% ethanol (EtOH) extract of Aquilaria sinensis leaves (AE), especially at high dose level (600 mg/kg), activated AMPactivated protein kinase (AMPK), resulting in reduced fasting blood glucose and glycosylated hemoglobin levels in db/db mice. In addition, the oral glucose tolerance test (OGTT test) showed that AE could remarkably improve insulin resistance. Compared to Thiazolinediones (TZDs), no weight gain was observed after AE administration, which is a severe side effect of TZDs. The data suggested that AE could act as an activator of AMPK, and might be used as an alternative to TZDs in the management of obesityrelated diabetes.