Hyoscyamus albus L. (Solanaceae) an old medicinal plant is a rich source of tropane and nortropane alkaloids which confers to this plant a number of very interesting and beneficial therapeutic effects.

Calystegines that are polyhydroxylated alkaloids and imino-sugars poccess significant glycosidases inhibitory activities and are therefore good candidats for the treatment of diabetes mellitus.

Calystegines extracted from Hyoscyamys albus seeds were tested for teir acute oral toxicity and investigated for their in-vivo antidiabetic effect on Streptozotocine induced diabetes in mice.

Calystegines were extracted from the seeds plant using an Ion exchange column; the remaining extract was then administrated orally to mice at several single doses for acute toxicity assay. A dose of 130mg/kg streptozotocine was injected to mice to induce diabetes mellitus, and diabetic mice were treated orally during 20days with 10mg/kg and 20mg/kg calystegines and 20mg/kg glibenclamide as the reference drug.

Acute oral toxicity showed that calystegines are not toxic up to a dose of 2000mg/kg with absence of any signs of intoxication and damages in Liver and kidney tissues.

The nortropane alkaloids markedly reduced blood glucose levels and lipid parameters of diabetic mice to normal concentrations after 20days of treatment at 10mg/kg and 20mg/kg (p<0.05). Histopathological study of diabetic mice pancreas indicated that calystegines of Hyoscyamus albus have minimized streptozotocine damages on β-cells of islets of langerhans, stimulated β-cells regeneration and improved with this insulin secretion.

The findings of this study suggest that calystegines are potent antidiabetic agents with antihyperglicemic and hypolipidemic effects, and a protective fonction on pancreas in streptozotocin induced diabetes in mice.