Inhibitory effect of Pingwei capsule on oxidative stress in GES-1 cells af-ter malignant transformation and its mechanism / 中国病理生理杂志

ABSTRACT

AIM:To observe the effect of Pingwei capsule on the precancerous lesions of gastric cancer(PLGC)cell model induced by N-methyl-N'-nitro-N-nitrosoguanidine(MNNG),and to preliminarily explore its mecha-nism.METHODS:Blank serum and Pingwei capsule-containing serum were prepared for later use.A PLGC cell model was established by MNNG-induced human gastric mucosal epithelial cell line GES-1.To evaluate the model,cell morpho-logical changes were observed under inverted microscope,and the expression of proliferating cell-related antigen Ki67 was detected by immunofluorescence staining.CCK-8 assay was used to screen the optimal intervention concentration and time of serum containing drugs.Reactive oxygen species(ROS)content in cells was detected using a fluorescent probe DCFH-DA.Malondialdehyde(MDA)content was detected by ELISA,and the activity of superoxide dismutase(SOD)and gluta-thione peroxidase(GSH-Px)was detected using biochemical reagents.A novel fluorescent probe JC-10 was used to detect mitochondrial membrane potential.The mRNA expression levels of Ki67 and melanoma differentiation-associated gene-7(MDA-7)were detected by real-time fluorescence quantitative PCR.The protein expression levels of Ki67,interleukin-6(IL-6)and MDA-7 were detected by Western blot.RESULTS:Compared with normal group,the ROS and MDA levels in model group and blank serum group were significantly increased(P<0.01),while the activity of SOD and GSH-Px was significantly decreased(P<0.01).The mitochondrial membrane potential was significantly decreased(P<0.01).The protein expression levels of Ki67 and IL-6 were significantly increased(P<0.01),while the protein expression level of MDA-7 was significantly decreased(P<0.01).There were no significant differences of the above indicators between model group and blank serum group(P>0.05).Compared with blank serum group,the Pingwei capsule-containing serum group showed significantly decreased ROS and MDA levels(P<0.01),significantly increased activity of SOD and GSH-Px(P<0.05),significantly increased mitochondrial membrane potential(P<0.01),significantly decreased protein expres-sion levels of Ki67 and IL-6(P<0.01),and significantly increased protein and mRNA expression levels of MDA-7(P<0.01).CONCLUSION:Pingwei capsule can significantly alleviate MNNG-induced oxidative damage and inflammatory response,and regulate the expression of oncogenes and tumor suppressor genes,thereby playing a role in prevention and treatment of PLGC.