Ceftazidime improves airway inflammation and obstruction in LPS-induced chronic bronchitis rat model by regulating Nfr2/HO-1 signaling pathway through miR-218-5p
Objective Research on Cefathiamidine improves chronic bronchitis induced by lipopolysaccharide(LPS)in rats by regulating the microRNA-218-5p(miR-218-5p)mediated Nuclear factor erythroid 2-related factor 2(Nfr2)/Heme oxygenase-1(HO-1)signaling pathway.Methods At the animal level,an LPS-induced CB model was established by intratracheal injection in this study.Forty rats were randomly divided into control group,model group,cefotaxime group(intramuscular injection of cefotaxime 200 mg·kg-1),and cefotaxime+miR-218-5p inhibitor group(intramuscular injection of cefotaxime 200 mg·kg-1+tail vein injection of miR-218-5p inhibitor 100 nmol·ml-1),with 10 rats in each group.Each group received medication twice a day for 3 consecutive days.HE was used to examine the histopathology of rat lung tissues;qRT-PCR was performed to detect miR-218-5p expression;Airway resistance(RI)was measured;ELISA was conducted to measure the levels of inflammatory mediators in bronchoalveolar lavage fluid;Immunofluorescence was used to detect positive expression of Mucoprotein5AC(MUC5AC)and Mucoprotein5B(MUC5B);Western blot was employed to assess the expression of Nrf2/HO-1 pathway-related proteins.At the cellular level,the cells were grouped according to the animal level.The ceftazidime group was treated with 10 μmol/L ceftazidime,and the ceftazidime+miR-218-5p inhibitor group was treated with 10 μmol/L ceftazidime+10 μmol/L miR-218-5p inhibitor.Nrf2,miR-218-5p,HO-1 targeting relationship,mRNA expression level and antioxidant level were detected by double luciferase assay,qRT-PCR and ELISA.Results Animal experiments show that the levels of miR-218-5p in the control group,model group,and cefotaxime group were 1.00±0.17,0.33±0.06,and 0.72±0.14,respectively.The RI in the control group,model group,cefotaxime group,and cefotaxime+miR-218-5p inhibitor group were(0.23±0.03),(0.62±0.08),(0.47±0.06),and(0.59±0.08)cmH2O·s·ml-1.IL-6 levels were(93.84±18.44),(231.16±46.98),(167.89±32.42),and(204.48±40.39)pg·ml-1,while TNF-α levels were(9.06±1.73),(44.03±8.17),(31.41±6.72),and(39.15±7.13)pg·ml-1.Macrophage inflammatory protein-1α levels were(724.32±133.82),(1 481.18±225.13),(1 007.50±196.69),and(1 226.76±207.27)pg·ml-1,and C-C motif chemokine ligand 5 levels were(166.07±33.61),(584.20±94.93),(322.55±57.34),and(463.89±84.04)pg·ml-1.The positivity rates for MUC5AC were(31.34±5.86)%,(75.48±10.99)%,(58.11±8.71)%,and(68.02±9.82)%,and for MUC5B were(29.62±5.90)%,(69.45±9.33)%,(48.27±8.07)%,and(56.85±9.04)%.The levels of Nfr2 were 1.00±0.18,0.67±0.13,1.36±0.26,and 0.94±0.15,and those of HO-1 were 1.00±0.19,0.52±0.12,0.93±0.15,and 0.79±0.13,respectively.All the differences between the model group and the control group,cefotaxime group and the model group,and cefotaxime+miR-218-5p inhibitor group and the cefotaxime group were statistically significant(all P<0.05).At the cellular level,the HO-1 WT luciferase activities of the control group,the model group,the ceftazidime group,and the ceftazidime+miR-218-5p inhibitor group were 1.00±0.16,0.48±0.07,0.78±0.10,and 0.65±0.09,respectively.The expression levels of Nrf2,miR-218-5p,and HO-1 mRNA and Nrf2,HO-1 protein in the ceftazidime group and the ceftazidime+miR-218-5p inhibitor group were higher than those in the model group.The level of ceftazidime group was higher than that of ceftazidime+miR-218-5p inhibitor group.Compared with the model group,the antioxidant level of the ceftazidime group and the ceftazidime+miR-218-5p inhibitor group increased,and the ceftazidime group was higher than the ceftazidime+miR-218-5p inhibitor group,the above differences were statistically significant(all P<0.05).Conclusion Ceftazidime can up-regulate Nfr2 and induce the expression of miR-218-50,thereby activating the Nfr2/HO-1 signaling pathway and improving LPS-induced airway inflammation and obstruction in CB rats.
Chronic bronchitisCefotetanmicro RNA-218-5pNuclear factor erythroid 2-related factor 2/Heme oxygenase-1 signal pathAirway inflammationIncreased mucus secretion in the airways
万方数据
维普
