(E)-9-oxooctadec-10-en-12-ynoic acid from Ixora brachiata Roxb. increases glucose uptake in L6 myotubes by activating the PI3K pathway

Abstract

In an attempt to discover new scaffolds for anti-diabetic activity from plants, we screened extracts from Ixora brachiata Roxb. for their effect on glucose uptake in L6 myotubes. The petroleum (PE) extract of the plant showed a significant increase in insulin stimulated glucose uptake by L6 myotubes. The bioactivity guided fractionation of the crude extract yielded a compound (E)-9-oxooctadec-10-en-12-ynoic acid (OEA). The compound induced a dose dependent increase in insulin stimulated glucose uptake in L6 myotubes with an EC₅₀ of 22.96μM. OEA also increased the phosphorylation of IRS-1, Akt and AS160 leading to increased GLUT4 translocation to the plasma membrane indicating that it promotes insulin stimulated glucose uptake in L6 myotubes by activating the PI3K pathway.

Keywords: (E)-9-oxooctadec-10-en-12-ynoic acid; Akt; GLUT4; Ixora brachiata; L6 myotubes.