Mechanism of nuclear factor-κB signaling pathway regulated nuclear factor erythroid 2-related factor 2 in human alveolar epithelial cells by bleomycin-induced

Abstract

Objective Observe nuclear factor (NF)-erythroid 2-related factor 2 (Nrf2) and its related gene expression changes after silencing of NF-κB in human alveolar epithelial cell (HPAEpiC) and to explore the mechanism of NF-κB signaling pathway regulated Nrf2 expression by bleomycin-induced.Methods Silencing of NF-κB using lentiviral technology in human alveolar epithelial cell (HPAEpiC).Using real-time fluorescent quantitative polymerase chain reaction (FQ-PCR) detect mRNA expression of Nrf2,Keap1,Cul3,Rbx1,protein kinase C (PKC),phosphatidylinositol 3 kinase (PI3K),extracellular signalregulated kinase (ERK),NF-κB and inhibitory κB (IκB) in human alveolar epithelial cells by Bleomycininduced.Cell apoptosis were determined by Annexin V-RFP single staining.NF-κB,Nrf2 and the associatedprotein expression were determined by Western blotting.Results Lentiviral infected HPAEpiC cells NF-κBgene expression decreased 90.6％,HPAEpiC cells which NF-κB silenced the gene expression of Nrf2 in-creased 142.6％ after Bleomycin-induced,it negatively correlated with NF-κB,IκB,Keap1,Cul3,Rbx1expression.PI3K expression increased 11.6-fold and PKC,ERK no significant change.The apoptosis rateincreased compared with the control group.Conclusion In process of bleomycin-induced,NF-κB in humanalveolar epithelial cell (HPAEpiC) can inhibit the function of Nrf2.NF-κB in the case of silence,Nrf2 viathe PI3K pathway while reducing Keap1-Cul3-RBx1 complex expression achieve activation,it may start itsdownstream oxidation reaction and reduce that bleomycin oxygen radicals cause damage to cells. Key words: Pulmonary fibrosis; Nuclear factor-κB; Nuclear factor erythroid 2-related factor 2; Signal transduction