The effect of Artemisia annua L. aqueous and methanolic extracts on insulin signaling in liver of HFD/STZ diabetic mice.

Objectives: Many studies have shown the anti-diabetic effects of medicinal plants. But their molecular mechanism has been less studied. Understanding of these mechanisms can help to better manage the treatment of diabetes by using these plants. So, this research examined the effect of Artemisia annua extract on PI3K (phosphatidylinositol 3-kinase)/AKt (serine/threonine kinase protein B) signaling pathway in liver of high-fat diet (HFD)/Streptozotocin (STZ)-induced type 2 diabetic mice.

Methods: Groups of mice were control, untreated diabetic mice, diabetic mice treated with various doses (400, 200, 100 mg/kg) of methanolic and aqueous extract of A. annua and metformin for four weeks. Type 2 diabetes was produced by feeding high-fat diet following injection of low dose of STZ. After experiment duration all mice were sacrificed and blood glucose, insulin, homeostasis model assessment of insulin resistance index (HOMA-IR), index of insulin sensitivity index (ISI) were detected and liver tissues were isolated for to detect m-RNA expression of PI3K and Akt.

Results: Extracts of aqueous and methanolic this plant markedly reduced hyperglycemia, hyperinsulinemia, HOMA-IR and elevated ISI in diabetic group in comparison with un-treated diabetic mice. In addition, they could enhance the expression of AKt and PI3K m-RNA in liver tissues in diabetic mice.

Conclusions: Artemisia annua extract ameliorated insulin resistance and improved insulin action in liver via the high activity of PI3K/AKt signaling pathway. So, it can be a suitable alternative treatment to synthetic antidiabetic drugs to improve insulin action in condition of type 2 diabetes.