Cytotoxic bufadienolides from the whole plants of Helleborus foetidus

Publication date: February 2018 Source:Phytochemistry Letters, Volume 23 Author(s): Akihito Yokosuka, Tomoki Iguchi, Riko Kawahata, Yoshihiro Mimaki Two new bufadienolides (1 and 2) and three known bufadienolide glucosides (3–5) were isolated from the whole plants of Helleborus foetidus (Ranunculaceae). The structures of 1 and 2 were determined spectroscopically. Compound 1 displayed potent cytotoxicity against HL-60 and A549 cells, with IC50 values of 0.035 and 0.029μM, respectively. HL-60 cells treated with 1displayed typical characteristics of apoptosis, such as nuclear chromatin condensation, DNA fragmentation, accumulation of sub-G1 cells, and marked activation of caspase-3. Moreover, the loss of mitochondrial membrane potential and release of cytochrome c into the cytosol suggested that 1 induced HL-60 cell death via the mitochondrial-dependent apoptotic pathway. Graphical abstract

Source: Phytochemistry Letters - December 16, 2017 Category: Chemistry Source Type: research