Study On The Mechanism Of NF-κB Signaling Pathway In The Injury Of Human Embryonic Lung Fibroblasts Induced By Sodium Arsenite

Objective To investigate the mechanism of nuclear factor κB(NF-κB)signaling pathway in the damage of Human embryonic lung fibroblasts(HELF)induced by sodium arsenite.Method HELF cells were exposed to 0(control group)0.625,1.25,2.5,5,10,20,40mmol/L sodium arsenite solution for 18,24,48 h.MTT assay was used to detect the cell survival rates.The morphology of HELF cells was detected by inverted microscope after 24 hours of exposure to sodium arsenite solution.The concentrations of TNF-a,IL-6 and IL-1β inflammatory factors in supernatant of HELF cells were detected by ELISA,except 40mmol/L group.HELF cells were divided into two groups,one group was sodium arsenite exposure group,and the other group was PDTC intervention group(PDTC:Pyrrolidine dithiocarboxylic acid ammonium salt).The sodium arsenite group was exposed to 0(control group),2.5,5,10,20mmol/L sodium arsenite solution,and the PDTC intervention group was added with the above concentration of sodium arsenite solution while adding 10mmol/L PDTC solution.After 24 h of exposure,the expression levels of p-p65 、 p-IKKβ and LC3II/I was detected by Western blot,detection of fluorescence intensity of LC3 protein by IF.Results(1)As the concentration of the drug increases,the HELF cells gradually change from a spindle shape to a round shape.(2)Compared with the control group,the survival rate of HELF cells in the groups of 2.5、5、10、20、40mmol/L sodium arsenite after treated 18,24,48 h was decreased,except 2.5mmol/L sodium arsenite after treated 48 h.Contrast difference have statistical significance(P<0.05).And with the increase of sodium arsenite exposure concentration and the extension of the exposure time,the survival rates of HELF cells decreased(P<0.01).(3)Compared with the control group,the concentration of TNF-αexposed to 1.25、2.5、5、10、20mmol/L sodium arsenite was increased,the concentration of IL-6 exposed to 5、10、20mmol/L sodium arsenite was increased,the concentration of IL-1β in the supernatant of HELF cells in all concentrations of sodium arsenite was increased.Contrast difference have statistical significance(P<0.05).With the increase of the concentration of sodium arsenite,all the concentrations of TNF-α,IL-6 and IL-1βin the supernatant of HELF cells increased.(4)Compared with the control group and the same concentration of PDTC intervention group,the expression levels of protein p-p65,p-IKKβ and LC3II/I protein in HELF cells in the group of exposured to 2.5、5、10、20mmol/L sodium arsenite were increased.Contrast difference have statistical significance(P<0.05).(5)Compared with the control group and the same concentration of PDTC intervention group,the LC3 protein fluorescence intensity of HELF cells in the group of exposured to 2.5、5、10、20mmol/L sodium arsenite was stronger.Conclusions Sodium arsenite can cause damage to human embryonic lung fibroblasts,promote the increase of inflammatory factors,cause autophagy and activate NF-κB signaling pathway.The NF-κB signaling pathway was inhibited and the expression level of autophagy-related proteins was decreased,suggesting that there is a positive correlation between NF-κB pathway and autophagy.