Study on the molecular mechanism of C-phycocyanin from Spirulina platensis induced apoptosis in HeLa cells / 中国药理学通报

ABSTRACT

Aim To investigate the influence and molecular mechanism of C-phycocyanin(CPC) from Spirulina platensis on apoptosis of HeLa cells in vitro.Methods Firstly,the effect of purified CPC on proliferation of HeLa cells in vitro was determined by MTT assay,and then electron microscope was exploited to observe the characteristic apoptotic features of cells treated with CPC.Subsequently,genomic DNA changes of HeLa cells were observed by agarose electrophoresis.Flow cytometric analysis revealed the influence of different concentrations of CPC on cell cycle of HeLa cells.The expressions of apoptosis related genes of CPC treated HeLa cells were determined by immunohistochemistry analysis.In addition,the activities of caspases and the release of cytochrome c from mitochondria into the cytosol were detected.Results Compared with control cells untreated with CPC,a significant decreased in the numbers of HeLa cells in survival treated with CPC and concentration dose effects existed.CPC could induce characteristic apoptotic features including cell shrinkage,membrane blebbing,microvilli loss,chromatin margination and condensation into dense granules or blocks.DNA of HeLa cells treated with CPC showed fragmentation pattern(DNA ladder of oligomers of 180~200 bp) typical for apoptotic cells.HeLa cells treated with different concentrations of CPC demonstrated an increasing percentage of cells in sub-G0/G1 phase.In addition,CPC could promote the expression of pro-apoptotic gene(Fas and ICAM-1);meanwhile,held back the anti-apoptotic gene(Bcl-2) expression,and then facilitated the transduction of tumoral apoptosis signals that resulted in the apoptosis of HeLa cells in vitro.In CPC treated HeLa cells,CPC treatment of HeLa cells also resulted in activation of caspases and release of cytochrome C from mitochondria into the cytosol.Conclusion C-phycocyanin from Spirulina platensis can induce the apoptosis of HeLa cells in vitro.By virtue of the promotion of the apoptosis signals transduction in HeLa,CPC realizes its antitumor activities.