Abstract: Objective To observe the relationship between nuclear factor kappB (NF - κB) activation and cell apoptosis,before and after LPS stimulation of human degene- rateve nucleus pulposus cells. Methods Degenerative human nucleus pulposus cells were cultured in vitro.Useing CCK-8 to observe the proliferative effect of LPS on the nucleus pulposus cells in vitro, in the concentration of 100, 200, 500 and 1 000 μg/mL and choose the most apropriate concentration. The experiment was divided into 3 groups: blank control group, LPS(500 μg/mL)groups, and NF-κB inhibitor（BAY11-7082）plus LPS(500 μg/mL)group,Annexin V-FITC/PI flow cytometry and Hoechest33258 staining was used to analyze apoptosis. The expression of cleaved caspase 3,PARP,P65,P-P65 proteins were detected by Western blot respectively. Results The results of CCK-8 assay showed that when LPS was 500 μg/mL, the cell vitality was declined obviously.Compared with the blank control group, cell apoptosis rate of the LPS group is increasing（p<0.05）,and the expression of P-P65,cleaved caspase 3,cleaved PARP were also higher (p< 0.05）.Compared with the LPS group, cell apoptosis rate of the NF-κB inhibitor plus LPS group is significantly lower (p<0.05) and the expression of P-P65,cleaved caspase 3,cleaved PARP were also lower (p< 0.05）.Conclusions NF-κB signaling pathway may be associated with the nucleus pulposus cell apoptosis in disc degeneration,so it was worth further study.

Key words: Key words: NF-κB, LPS , Nucleus pulposus cells, Apoptosis