Dammarane-type triterpenoids from Gynostemma compressum X. X. Chen & D. R. Liang (Cucurbitaceae) and their AMPK activation effect in 3T3-L1 cells.

Bioassay-guided fractionation of the 80% ethanol extract of Gynostemma compressum X. X. Chen & D. R. Liang (Cucurbitaceae) resulted in the isolation and identification of eight undescribed triterpenoids, gycomol VN1, gycomol VN2, and gycomosides VN1-6 from the bioactive n-butanol fraction. The structures of these compounds were elucidated by one- and two-dimensional nuclear magnetic resonance spectroscopy, high-resolution electrospray ionisation mass spectrometry, and chemical methods. All isolated compounds were evaluated for their 5'-adenosine monophosphate-activated protein kinase (AMPK) and acetyl-coenzyme A carboxylase (ACC) activation effects on 3T3-L1 cells. Importantly, gycomol VN2, gycomoside VN1, and gycomosides VN3-5 activated the phosphorylation of AMPK and its downstream substrate ACC in 3T3-L1 cells at a dose of 10 μM. These effects imply that the activation of AMPK and ACC by active compounds from G. compressum has considerable potential for the prevention of obesity and its related disorders by activating AMPK signaling pathways.