Effect of epoxides and α-methylene-γ-lactone skeleton of sesquiterpenes from yacon (Smallanthus sonchifolius) leaves on caspase-dependent apoptosis and NF-κB inhibition in human cercival cancer cells

The present study investigated the cytotoxicity of enhydrin (1), uvedalin (2) and sonchifolin (3) in cervical cancer cells. We have found that SLs 1-3 in doses in range of 0.22-10 mu M inhibited cell proliferation and induced apoptosis in both a dose- and time-dependent fashion. A significant cell death induction was supported by morphological studies. The apoptotic effect is associated with caspase-3/7 activation and NF-kappa B inhibition. Interestingly, enhydrin possessing two epoxide units was found to be the most cytotoxic compound. Therefore it can be assumed that number of epoxides and existence of alpha-methylene-gamma-lactone moiety are essential for the acceleration of apoptosis. (C) 2011 Elsevier B.V. All rights reserved.