North American Ginseng (Panax quinquefolius) prevents hyperglycemia and associated pancreatic abnormalities in diabetes.

North American ginseng (NAG) has received increasing attention as an alternative medicine for the treatment of diabetes. Extract of the NAG root has been reported to possess antidiabetic properties, but the underlying mechanisms for such effects have not been identified. Here we investigated the effects of NAG root extract on type 1 and 2 diabetes and the underlying mechanisms involved for such effects. Type 1 [C57BL/6 mice with streptozotocin (STZ)-induction] and type 2 (db/db) diabetic models were examined. Groups of diabetic mice (both type 1 and 2) were treated with alcoholic extract of the NAG root (200 mg/kg BW/day, oral gavage) for 1 or 2 months following onset of diabetes. Ginseng treatment significantly increased the body weight in type 1 diabetic animals in contrast to the type 2 model, where it caused diminution of body weight. Blood glucose and glycated hemoglobin levels diminished in the diabetic groups of both models with NAG treatment. Interestingly, plasma insulin and C-peptide levels were significantly increased in the STZ-diabetic mice, whereas they were reduced in the db/db mice following NAG treatment. Histological and morphometric analyses (islet/pancreas ratio) of the pancreas revealed an increase in the islet area following the treatment compared to both the untreated diabetic groups. These data indicate that NAG possibly causes regeneration of β-cells resulting in enhanced insulin secretion. On the other hand, in type 2 diabetes, the additional effects of NAG on body weight might have also resulted in improved glucose control.