The effects of naringin on the expression of miR-19b and cell apoptosis were investigated in the human hepatocellular carcinoma cell line HepG2. HepG2 cells were treated with varied concentrations of naringin. The effects of naringin on the proliferation of HepG2 cells were observed by an MTT assay, morphological changes of cells were observed by an inverted microscope, cell apoptosis was detected by DAPI staining, miR-19b mRNA levels were determined with RT-PCR, and the expression of Bax and Bcl-2 proteins was examined by western blot assay. MTT results showed that naringin significantly inhibited the proliferation of HepG2 cells. Apoptotic HepG2 cells showed obvious changes in morphology under inverted microscope. DAPI staining suggested that naringin could induce cell shrinkage and nuclear chromatin condensation. RT-PCR results showed that naringin could upregulate the expression of miR-19b mRNA. Finally, western blot suggested that naringin upregulated the expression of Bax protein, but downregulated the expression of Bcl-2 protein. In conclusion, naringin can upregulate the expression of miR-19b mRNA and induce HepG2 cell apoptosis. In addition, it can also upregulate the expression of Bax protein and downregulate the expression of Bcl-2 protein during the process of apoptosis.
Keywords: Bax; Bcl-2; apoptosis; human hepatocellular carcinoma cell line HepG2; miR-19b; naringin.