Sweet gum (Liquidambar styraciflua L., family Hamamelidaceae) fruit extract was discovered to possess potent activities against multiple targets of the PI3K (phosphatidylinositide 3-kinase) pathway, especially the PI3K/Akt and mTOR pathways. At a very low concentration of 1.85 μg/ml (IC50), sweet gun extract showed the ability of simultaneously blocking the pathways of PI3K/Akt (upstream), mTOR (mammalian target of rapamycin) (downstream), as well as its downstream protein products S6K and S6. It was also able to block 5-HETE, a lipoxygenase product that contributes to inflammation and activation of PI3K/Akt. The sweet gum fruit extract was prepared with 50% methanol (47:1 raw to extract) and concentrated to an organic fraction (210:1 raw to extract) referred as LIS-100 via reverse-phase column chromatography using a bioassay directed fractionation approach. The extract is a new targeted therapeutic agent for numerous disorders known to be treated by mTOR inhibitors, including cancer, diabetes, obesity, and inflammation.
