Effects of NF-κB/NOX1 signaling pathway in TNF-α-induced apoptosis of A549 cells / 中国职业医学

ABSTRACT

OBJECTIVE: To investigate the effects of nuclear transcription factor-κB(NF-κB)/amide adenine dinucleotide phosphate oxidase 1(NOX1) signaling pathway in tumor necrosis factor-α(TNF-α) induced apoptosis of A549 cells. METHODS: i) A549 cells were stimulated with TNF-α at the concentrations of 0.00, 0.25, 0.50, and 1.00 nmol/L. CCK-8 assay was used to detect the cell viability to screen the optimal stimulating concentration of TNF-α. ii) A549 cells at logarithmic growth stage were randomly divided into four groups, the control group, the TNF-α group, the BAY11-7082(NF-κB inhibitor) group and the TNF-α+BAY11-7082 group. The cells in the control group were not treated. The TNF-α and BAY11-7082 groups were stimulated with 0.50 nmol/L TNF-α and 5 μmol/L BAY11-7082, respectively. The TNF-α+BAY11-7082 group was stimulated by both TNF-α and BAY11-7082. After 24 hours of culture, the cell survival rate was detected by CCK-8 assay. Flow cytometry was used to detect cell apoptotic rate, and Western blotting was used to detect the relative expression of NF-κB(p65) and NOX1 proteins. RESULTS: i) When A549 cells were stimulated with TNF-α at the concentration of 0.50 nmol/L, the cell proliferative activity was reduced and the cell apoptosis was promoted. This concentration was selected as the stimulation dose of TNF-α in subsequent experiments. ii) The survival rate of A549 cells in the TNF-α group decreased(P<0.05), the apoptotic rate and the protein expressions of NF-κB(p65) and NOX1 increased in TNF-α group(all P<0.05) compared with the control group. In BAY11-7082 group, the survival rate and the relative expression of NF-κB(p65) and NOX1 of A549 cells were decreased(all P<0.05), and the apoptotic rate of A549 cells was increased(P<0.05) compared with the control group. A549 cells in TNF-α+BAY11-7082 group changed from a long spindle shape to an irregular one. The cell survival rate increased(P<0.05), the apoptotic rate and the relative expression of NF-κB(p65) and NOX1 decreased(all P<0.05) compared with the TNF-α group. CONCLUSION: NF-κB/NOX1 signaling pathway is involved in A549 cells apoptosis induced by TNF-α.