Study on the mechanism of regulating c-Jun expression by budesonide to inhibit oxidative stress damage in alveolar macrophages NR8383
Objective To investigate the protective mechanism of oxidative stress injury of SD rats NR8383 by budesonide.Methods Rat alveolar macrophages NR8383 were divided into 5 groups:blank group was given serum-free K12 medium without any treatment;lipopolysaccharide(LPS)group was given 2.29 μg·mL-1 LPS standard solution;budesonide group(budesonide),c-Jun inhibitor group(AS601245)and budesonide+c-Jun inhibitor group(budesonide+AS601245)were given budesonide 28.0 μL,c-Jun inhibitor AS601245 2.50 μg,and budesonide 28.0 μL+c-Jun inhibitor AS601245 2.50 μg based on the LPS group,respectively.Cells in 5 groups were incubated in serum-free K12 medium at constant temperature for 24 h.The apoptosis rate at 24 h was examined by cell counting kit-8(CCK-8)assay;c-Jun mRNA expression was detected by real-time quantitative polymerase chain reaction(q-PCR);oxidative stress damage factor reactive oxygen species(ROS),8-hydroxy-2-deoxyguanosine(8-OHdG),glutathione peroxidase(GSH-Px),thioredoxin reductase-1(TRX-1)expression were detected by enzyme-linked immunosorbent assay(ELISA);c-Jun signaling pathway protein expression in each group by Western blot.Results Compared with LPS group(29.88±5.98)%,24 h apoptosis rate was significantly decreased in budesonide group,c-Jun inhibitor group,budesonide+c-Jun inhibitor group and blank group[(20.15±6.66)%,(15.39±3.54)%,(12.11±2.55)%and(8.52±1.27)%,respectively],the differences were statistically significant(all P<0.05).The ROS in budesonide group,c-Jun inhibitor group,budesonide+c-Jun inhibitor group,LPS group and blank group were(3.16±0.19),(4.15±0.33),(2.21±0.21),(6.52±0.36)and(1.06±0.23)U·g-1;8-OHdG were(10.55±1.23),(11.14±1.06),(9.55±1.00),(15.66±1.99)and(8.27±1.13)ng·mL-1;GSH-PX were(188.52±12.33),(200.52±27.97),(144.52±20.55),(335.14±30.10)and(126.55±12.52)U·mL-1;TRX-1 were(40.11±6.66),(50.55±10.07),(60.25±10.55),(115.36±20.03)and(16.55±2.33)ng·mL-1;the relative c-Jun mRNA expressions were 0.56±0.03,0.44±0.11,0.25±0.04,0.89±0.12 and 0.08±0.01;c-Jun/GAPDH protein relative expression were 3.15±0.22,2.36±0.14,1.55±0.13,4.02±0.22 and 0.88±0.12.Compared with the LPS group,the differences of indicators in the budesonide group,c-Jun inhibitor group and budesonide+c-Jun inhibitor group possessed statistical significance(all P<0.05).Conclusion Budesonide significantly increased the survival rate of NR8383 cells and significantly decreased the concentrations of oxidative damage representative factors ROS,GSH-Px,8-OHdG and TRX-1,its oxidative damage protection mechanism may be related to the regulation of c-Jun protein.