Fuzheng Qingjie recipe induces apoptosis in HepG2 cells via P38 MAPK activation and the mitochondria-dependent apoptotic pathway

Abstract

Fuzheng Qingjie (FZQJ) recipe is a polyherbal Chinese medicine capable of suppressing tumor growth and is used as an adjuvant therapy for various types of cancer. However, its anticancer mechanisms are yet to be fully elucidated. In the present study, we explored whether p38 mitogen-activated protein kinase (MAPK) was involved in FZQJ-mediated mitochondria-dependent apoptosis in human hepatocellular carcinoma cells. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were used to measure the viability of HepG2 cells. 4,6-Diamidino-2-phenylindole (DAPI) and Annexin-V fluorescein isothiocyanate (FITC) were used to analyze the apoptosis of HepG2 cells. The mitochondrial membrane potential (∆ψ) and phosphorylated P38 MAPK protein were examined by a flow cytometer following 5,5',6,6'-tetrachloro‑1,1',3,3'-tetraethylbenzimidazolcarbocyanine iodide (JC-1) and Alexa Fluor® 647 mouse anti-phosphorylated P38 MAPK antibody staining, respectively. The activation of caspase-9 and caspase-3 were measured using colorimetric assays. Additionally, Bcl-2 and Bax expression were examined using reverse transcription polymerase chain reaction (RT-PCR) and western blot analysis. The results demonstrated that water extract of FZQJ was able to induce apoptosis of HepG2 cells in vitro. FZQJ-induced apoptosis was accompanied by the loss of ∆ψ, downregulation of Bcl-2 and upregulation of Bax expression, and the activation of caspase-3, -9 and P38 MAPK. These results indicated that FZQJ induced apoptosis in HepG2 cells at least via P38 MAPK activation and the mitochondria-dependent apoptotic pathway.