单增李斯特菌感染抑制HepG2细胞RhoA表达并促进其凋亡

Increased apoptosis and down-regulation of Rho A in HepG2 cells infected by Listeria monocytogenes

目的探讨单增李斯特菌(Lm)调控Hep G2细胞的凋亡能力以及对Rho家族Rho A蛋白表达的影响。方法常规方法培养Hep G2细胞,分别以感染复数(MOI)=10和MOI=100接种Lm菌EGD株,共培养1 h和20 h后收集培养物。异硫氰酸荧光素标记的膜联素Ⅴ/碘化丙啶(annexinⅤ-FITC/PI)双染色结合流式细胞术检测细胞凋亡率,反转录PCR检测Hep G2细胞Rho A和caspase 3编码基因表达,分光光度法检测Hep G2细胞活化的caspase 3水平,Western blot法检测Hep G2细胞Rho A蛋白表达。结果 Lm的侵袭可促进Hep G2细胞凋亡,下调Hep G2细胞Rho A编码基因和蛋白表达,并上调caspase 3编码基因表达。结论 Lm感染促进宿主细胞凋亡,抑制宿主细胞Rho A表达。

Objective To explore the apoptosis of HepG2 cells infected by Listeria monocytogenes EGD strain （Lm-EGD） as well as Rho family small GTPases RhoA expression. Methods HepG2 cells were infected with Lm-EGD （MOI = 10 and MOI = 100） and collected 1 hour and 20 hours after infection. After harvesting, the apoptosis of HepG2 cells was determined by flow cytometry combined with annexin V-FITC/PI assay. RhoA and caspase 3 mRNAs were analyzed by reverse-transcdption PCR. The caspase 3 activity was detected by colodmetdc assay. And Westem blotting was used to detect RhoA expression in HepG2 cells. Results Lm invasion promoted HopG2 cell apoptosis and down-regulated P, hoA mRNA and protein expression. Additionally, caspase 3 expression was up-regulated following Lm infection, Conclusion Lm infection could promote host cell apoptosis and down-regulate RhoA expression.