[Effect of Weifuchun on inhibiting inflammation of Helicobacter pylori-infected GES-1 cells and NF-kappaB signaling pathway]

Abstract

Objective: To study the effect of Weifuchun on inflammation of Helicobacter pylori (Hp)-infected gastric epithelial cells (GES-1) and its correlation with NF-kappaB signaling pathway.

Methods: Hp standard home-made strain (CagA +, VacA +) NCTCI 1637 infected GES-1 cells were used. Weifuchun was used as intervention. Weifuchun of different concentrations (5,10, and 20 microg/mL) were screened by MTT assay. A blank group and the model group were set up. Then the growth inhibition rate of drugs on gastric epithelial GES-1 cells was detected with MTT assay. Cell cycle was detected using flow cytometry. The supernatant liquid was separated to detect the contents of IL-8 and IL-4 by ELISA.The protein expression level of NF-kappaB was detected by Western blot analysis.

Results: MTT assay indicated significantly inhibitory effect of Weifuchun on GES-1 cells [5% inhibiting concentration (IC5)] was 10 microg/ml in the Weifuchun group. After GES-1 and Hp were cultured together,the contents of IL-8 in the supernatant were more obviously higher in the model group than in the blank group (P < 0.05), and then gradually decreased. After treatment with different concentrations of Weifuchun, the levels of IL-8 in the supernatant were less when compared with the model group at 12, 24, 48, and 72 h (P < 0.05). The decrement was the most significant in the high dose Weifuchun group. The IL-4 level in the supernatant was obviously lower in the model group than in the blank group. It obviously increased in the high concentration Weifuchun group (P < 0.05). There was no statistical difference in the IL-4 level between middle, low concentration Weifuchun group and the blank group (P > 0.05). The protein expression of intranuclear P65 increased and that of IkBalpha decreased 60 min after Hp infection. But the protein expression of intranuclear P65 decreased and the protein expression of IkBalpha increased after intervention of Weifuchun.

Conclusions: Weifuchun adjusted H. pylori induced IL-8 and IL-4 production by gastric epithelial cells through blocking NF-kappaB pathways. Its mechanisms might possibly lie in inhibiting p65 from entry into nucleus and the degradation of IkBalpha. Weifuchun was an effective drug for treatment of Hp correlated chronic gastritis.