Convallatoxin is widely used as a
cardiac glycoside in acute and chronic
congestive heart-failure and
paroxysmal tachycardia, with many effects and underlying protective mechanisms on
inflammation and cellular proliferation. However,
convallatoxin has not been investigated in its
antioxidant effects and lifespan extension in Caenorhabditis elegans. In this study, we found that
convallatoxin (20 μM) could significantly prolong the lifespan of wild-type C. elegans up to 16.3% through daf-16, but not sir-2.1 signalling and increased thermotolerance and resistance to
paraquat-induced oxidative stress.
Convallatoxin also improved pharyngeal pumping, locomotion, reduced
lipofuscin accumulation and
reactive oxygen species levels in C. elegans, which were attributed to hormesis,
free radical-scavenging effects in vivo, and up-regulation of stress resistance-related
proteins, such as SOD-3 and HSP-16.1. Furthermore, aging-associated genes daf-16, sod-3, and ctl-2 also appeared to contribute to the stress-resistance effect of
convallatoxin. In summary, this study demonstrates that
convallatoxin can protect against heat and oxidative stress and extend the lifespan of C. elegans, pointing it as a potential novel drug for retarding the aging process in humans.