温郁金二萜类化合物C对幽门螺杆菌诱导人胃GES-1上皮细胞炎症的抑制作用及其对NF-κB信号通道的影响

Effect of diterpenoid C extracted from radix curcumae on inflammation and NF-κB signaling pathway in helicobacter pylori-infected gastric epithelial cells

目的通过体外实验研究温郁金二萜类化合物C对幽门螺杆菌(helicobacter pylori,Hp)诱导炎症的抑制作用及对NF-κB信号通路的影响。方法选用Hp I型菌株感染人胃上皮细胞株GES-1,建立体外Hp感染细胞模型,并予不同浓度温郁金二萜类化合物C、阿莫西林等进行干预,ELISA法检测上清液中IL-8、IL-4,并应用Wester blot方法检测NF-κB中p65、IKKα、IKKβ蛋白表达。结果 MTT法显示温郁金二萜类化合物C对胃GES-1细胞的IC5为5 mg.L-1,阿莫西林为5 mg.L-1,Hp作用于人胃GES-1上皮细胞后,上清液中IL-8明显升高,其中以12 h浓度最高,而予不同浓度温郁金二萜类化合物C、阿莫西林组干预后,IL-8水平在各个时间段均低于模型组,其中以高浓度温郁金二萜类化合物C组下降最为明显(P<0.05)。而IL-4水平在Hp作用于人胃GES-1细胞后下降,予中浓度温郁金二萜类化合物C组、高浓度二萜类化合物C组干预后IL-4水平明显升高(P<0.05)。温郁金二萜类化合物C具有抑制Hp促p65进入胞核,抑制Hp所刺激的IkBα的降解,抑制p65、IkBα磷酸化,抑制蛋白IKKα、IKKβ的表达等作用。结论 NF-κB信号通路在Hp引起慢性胃炎的发病机制中起到核心作用,采用温郁金二萜类化合物C可阻断NF-κB信号通路,可以有效减少Hp诱导的促炎性因子的分泌与增加抑炎因子的分泌。

Aim To study the effect of diterpenoid C extracted from radix curcumae on inflammation,intestinal metaplasia,and NF-κB signaling pathway in helicobacter pylori（Hp）-infected gastric epithelial cells in vitro experiment.Methods Helicobacter pylori standard strain and gastric epithelial cells were cultured.The effect of different concentrations of diterpenoid C extracted from radix curcumae on human gastric epithelial GES-1 cells was observed with amoxicillin as positive control.The inhibition of drugs on gastric epithelial GES-1 cells was evaluated with MTT assay.The protein expression level of p65,IKKα,IKKβ was detected by Western blot analysis.The supernatant liquid was separated to detect the contents of IL-8 and IL-4 by ELISA.Results MTT assay indicated significantly inhibitory effect of diterpenoid C on GES-1 cells with 5 % inhibiting concentration（IC5） of 5 mg·L-1 in diterpenoid C group and 5 mg·L-1 in amoxicillin group.The Hp standard strain（1637 strain）and GES-1 were cultured successfully.After GES-1 and Hp were cultured together for 12h,24h,48h,72h,the contents of IL-8 in the supernatant liquid were more than those in the blank group,and reached the highest level at 12 h.After treatment with different concentrations of curcumrinol C（5,10,20 mg·L-1） or amoxicillin,the levels of IL-8 in the supematant liquid were less than those in the group of GES-l and Hp at 12,24,48,72 h（P＆lt;0.05）.Helicobacter pylori could lead to the inhibition of the IL-4 expression on GES-1 cell,and the levels of IL-4 could increase at curcumrinol C（5,10,20 mg·L-1）.Our results demonstrated that curcumin inhibited the activity of IKKα,inhibited phosphorylation of p65,IkBα and inhibited the protein expression of IKKα,IKKβ in helicobacter pylori-induced gastritis.Conclusions The NF-κB signaling pathway plays an important role in the pathogenic mechanism of gastritis associated with helicobacter pylori infection.Curcumrinol C adjusted H.pylori-induced IL-8 and IL-4 production by gastric epithelial cells through the modulation of NF-κB pathways.