Abstract:
Objective To investigate the effect of quinalizarin on the apoptosis of hepatoma Huh7 cells and to explore its possible mechanism.
Methods Human hepatoma HepG2, Hep3B and Huh7 cells viabilities were detected by MTT assay. The morphological alterations of Huh7 cells were demonstrated by inverted microscope. Cell apoptosis was analyzed by Annexin V-FITC/PI double staining and flow cytometry. The expressions of apoptotic proteins were detected by Western blot. The levels of ROS were measured by flow cytometry after quinalizarin treatment.
Results MTT assay results suggested that compared with control group (0 h), quinalizarin significantly inhibited the viabilities of human hepatoma HepG2, Hep3B and Huh7 cells in a dose-dependent manner (P=0.0204). The apoptotic morphology of Huh7 cells in the experimental group was found under the inverted microscope, such as cell shrinkage, karyopyknosis. The apoptotic rates of Huh7 cells in 24 h experimental group was 50.63%, significantly higher than that in 0 h control group (15.58%) (P=0.0001). Akt inhibitor pretreatment could synergize with quinalizarin to upregulate the expression levels of Bad and cleaved-caspase-3 protein, and downregulate the expression levels of p-Akt and Bcl-2 (P < 0.05). The intracellular reactive oxygen species (ROS) level was increased after quinalizarin treatment.
Conclusion Quinalizarin could inhibit the proliferation of Huh7 cells in a dose-dependent manner. Its mechanism may be related to quinalizarin down-regulating the expression of phosphorylated Akt or inducing the levels of ROS, and then to promote the Huh7 cells apoptosis.