Dibenzocyclooctadiene lignans from Fructus Schisandrae Chinensis improve glucose uptake in vitro.

Glucose uptake assay-guided fractionations of the methanol extract of Schisandra chinensis led to the isolation of the dibenzocyclooctadiene lignans: gomisin J (1), gomisin N (2), wuweizisu B (3), wuweizisu C (4), gomisin C (5), gomisin D (6), (+)-schisandrin A (7), schisandrin C (8), schisandrol A (9), gomisin H (10), angeloylgomisin H (11), gomisin A (12), and schizandrin (13). Among these, 1, 2, 7, and 8 significantly improved basal glucose uptake in HepG2 cells. Their improving effects were concentration-dependent. Compound 2 exhibited a stronger effect than that of rosiglitazone, which has been used as an anti-diabetic drug. The results suggest that these lignans may partially contribute to the anti-diabetic activity of Fructus Schisandrae Chinensis in traditional use by stimulating the glucose uptake into peripheral tissue, which may be responsible for reducing the level of blood glucose in circulation. Thus, these findings show the potential of these lignans for development as hypoglycemic drugs.