Ellagitannins from Lagerstroemia speciosa as Activators of Glucose Transport in Fat Cells

Abstract

Glucose transport enhancers were searched for in Lagerstroemia speciosa, a Philippine local herbal medicine used for diabetes mellitus. Bioassay-guided fractionation of the aqueous acetone extract of the leaves afforded three active ellagitannins, lagerstroemin, flosin B and reginin A, identified by NMR and optical rotation. These compounds increased glucose uptake of rat adipocytes, and could be responsible for lowering the blood glucose level.

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