Objective:To investigate the molecular mechanisms by which Qianliening Capsule(前列宁胶囊,QC) treats benign prostatic hyperplasia(BPH).Methods:Human prostate stromal cell line WPMY-1 was treated with 0,1,3 and 5 mg/mL of QC for 24,48 and 72 h,respectively,in the presence of 10 ng/mL basic fibroblast growth factor(bFGF).The viability of WPMY-1 cells was determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay.Cell morphology was observed by phase-contrast microscopy.4’,6-diamidino-2-phenylindole (DAPI) staining and fluorescence activated cell sorting(FACS) analysis with Annexin-V/propidium iodide(PI) staining were performed to determine cell apoptosis.The loss of mitochondrial membrane potential was examined by FACS analysis with 5,5’,6,6’-tetrachloro-1,1’,3,3’-tetraethylbenzimidazolyl-carbccyarine iodide(JC-1) staining. Activation of caspase-3 and -9 was evaluated by colorimetric assay.The mRNA and protein expression levels of Bcl-2 and Bax were measured by reverse transcription polymerase chain reaction(RT-PCR) and Western blotting,respectively.Results:Upon bFGF stimulation,the viability of WPMY-1 cells was increased to 122%-118% compared with the control cells(P<0.05).However,treatment with 1-5 mg/mL of QC for 24,48 and 72 h decreased the viability of bFGF-stimulated cells to 80%-92%,59%-82%,36%-62%compared with the untreated cells(P<0.05).In addition,QC treatment reduced WPMY-1 cell density in a dose-dependent manner.Moreover, QC treatment dose-dependently induced the loss of plasma membrane asymmetry,the nuclear condensation and fragmentation,collapse of mitochondrial membrane potential,activation of caspase-9 and caspase-3,and increase of pro-apoptotic Bax/Bcl-2 ratio.Conclusion:Promoting mitochondrion-dependent apoptosis of prostate stromal cells might be one of the mechanisms by which QC treats BPH.
