[Study on anti-proliferation activity and the mechanisms of alkaloid monomers from Gelsemium elegans on HepG2 cell in vitro].

ABSTRACT

OBJECTIVE: To investigate the effects of alkaloid monomers from Gelsemium elegans on proliferation of HepG2 cell in vitro and the possible mechanism. METHODS: MTT assay was used to measure the inhibitory of three alkaloid monomers on HepG2 cell in vitro. The most effective fraction was chosen to test whether the effect was in time-and dose-dependent manner. The morphological changes were observed by the light microscope and the cell cycle alteration through the flow cytometric assay. The activity of Caspase-3, Caspase-8 and Caspase-9 were detected by a Caspases colorimetric assay kit. RESULTS: The results showed that koumine, Gelsemine and Gelsenicine could significantly inhibit the proliferation of HepG2 cell and Gelsenicine, the most effective fraction, was clearly in dose- and time-dependent manners, while exhibited low cytotoxicity to the Vero cell. The cell treated with Gelsenicine for 48 h showed distinctive morphological changes. The cells treated with 200 and 400 microg/mL shrinked and fell off from the bottom. At the same time, the cells were arrested at S phase and the apoptosis increased apparently. The activity of Caspase-3, Caspase-8 and Caspase-9 was increased in a dose-dependent manner. CONCLUSION: Three alkaloid monomers from Gelsemium elegans, especially Gelsenicine, could inhibit proliferation of HepG2 cell obviously. The mechanism may be related to cell cycle arrest and activation of Caspase-3, Caspase 8 and Caspase-9.