ObjectiveTo explore the role of osteopontin (OPN) in hyperoxia-induced acute lung injury and its relationship with nuclear factor-κB (NF-κB),matrix metalloproteinase 2 and 9 (MMP-2,MMP-9). MethodsNinety-six mice were randomly divided into a phosphate buffer solution intranasal inhalation group (PBS group) and a recombinant OPN intranasal inhalation group. The mice were exposed in sealed cages >95% oxygen for 24-72 hours to induce lung injury or room air as control. The severity of lung injury was evaluated. The expression of NF-κB,MMP-2,MMP-9,TIMP-1 and TIMP-2 mRNA in lung tissue at 24,48 and 72 hours under hyperoxia were examined by reverse transcript-polymerase chain reaction (RT-PCR). Immunohistochemistry (IHC) was performed for detection of NF-κB protein in lung tissue. ResultsPBS group mice developed more severe acute lung injury at 72 hours under hyperoxia.TIMP-1 and TIMP-2 mRNA expressions were significantly increased in r-OPN group than their matched PBS group when exposed to hyperoxia. IHC study showed higher expression of NF-κB protein in lung tissue of PBS group at 72 hours of hyperoxia. ConclusionOPN can protect against hyperoxia-induced lung injury by inhibiting the expressions of NF-κB,MMP-2 and MMP-9.
Objective To investigate the expression of transcription factors including nuclear factor-κB （NF-κB） and activator protein-1 （AP-1） in vascular endothelial cells （ECs） in different flow fields， and provide experimental evidence for mechanical signal effects on gene regulation pattern of ECs. Methods Cultured human umbilical vein ECs were loaded into steady flow chambers of laminar flow or turbulent flow and observed at 6 time points （0.5 h， 1 h， 2 h， 3 h， 4 h and 5 h） based on different load time. Spacial and temporal characteristics of NF-κB and AP-1 expression in ECs in different flow chambers were detected at a protein level by laser confocal microscope. Results In laminar flow， NF-κB expression rose to peak at 1 hour （26.49±1.63， P＜0.05）and then declined. In turbulent flow， NF-κB expression rose to peak at 3 hours （34.41±6.43， P＜0.05）. In laminar flow， c-Jun/AP-1 expression was transiently elevated， reached its peak at 0.5 hour （18.95±5.38，P＜0.05）and then fell to its baseline level. In turbulent flow， c-Jun/AP-1 expression rose slowly but steady to peak（P＜0.05） . Conclusion The effects of turbulent flow on NF-κB and AP-1 expression in ECs are different from those of laminar flow. Up-regulation and activation of NF-κB and AP-1 expression in ECs induced by turbulent flow may cause pathological changes in morphological structure and functional behavior of ECs.
Objective To investigate the role of alveolar macrophages ( AMs ) in airway inflammation of smoke-induced COPD rat model and its possible regulating mechanism. Methods Twelve Wistar rats were randomly divided into a COPD group and a control group. The rat model of COPD was established with smoke exposure and LPS intrathacheal instillation. Bronchoalveolar lavage fluid ( BALF)was collected for measurement of total and differential cell counts. Then AMs were isolated and identified byimmunofluorescence. Western blot was employed to analyze the cytoplasmic and nuclear NF-κB p65 expression of AMs. The concentrations of TNF-α,macrophage inflammatory protein 2 ( MIP-2) and IL-10 in cell culture supernatantwere assayed by ELISA.Results The scores of bronchitis and mean liner intercepts in the COPD group were significantly higher than those in the control group [ 4. 33 ±1. 16 vs. 1. 33 ±0. 58,P =0. 016; ( 168. 77 ±11. 35) μm vs. ( 93. 61 ±4. 16) μm, P = 0. 000) ] . The total cell count in BALF of the COPD group was significantly higher than that in the control group ( P lt; 0. 05) , and the AMs and neutrophils were predominant [ ( 72. 00 ±2. 22) % and ( 18. 29 ±8. 34) % ] . The cytoplasmic NF-κB p65 expression of AMs in the COPD group was significantly lower , while the nuclear NF-κB p65 expression was significantly higher ( P lt; 0. 05) compared with the control group. The ELISA results showed that the concentrations of TNF-αand MIP-2 in culture supernatant of AMs in the COPD group were significantly higher than those in the control group ( P lt;0. 05) , while the concentration of IL-10 was not significantly different between the two groups ( P gt;0. 05) . Conclusions COPD rat model was established successfully with smoke exposure and LPS intratracheal instillation with a profile of macrophage-based chronic inflammation and increased secretion of TNF-αand MIP-2. The mechanismis closely related to activation of NF-κB.
ObjectiveTo observe the effect of rosiglitazone on cognitive function, serum high sensitive C reactive protein (hs-CRP) and expression of nuclear factor-κB (NF-κB), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) in hippocampal tissues of senile diabetic rats. MethodsThirty aged Wistar rats (20-22 months) were randomly divided into normal control group (n=6), diabetic model group (n=12), and rosiglitazone treatment group (n=12). Streptozotocin-induced diabetic rat model was established. In the rosiglitazone treatment group, the rats were treated with rosiglitazone 4mg/kg/d for 8 weeks. The cognitive function of rats was evaluated with the Morris water maze test. Serum hs-CRP was detected by ELISA. The expression of NF-κB in hippocampal tissues was detected by western blot and IL-6 and TNF-α by Real-time PCR. ResultsThe Morris water maze test showed that escape latency was longer in the rosiglitazone treatment group and the diabetic model group than that in the control group (P<0. 05). Compared with the diabetic model group, the rosiglitazone treatment group showed a significant decrease in the average time of escape latencies (P<0.05), and an increased percentage of time spent in the central area and the more times navigating the original platform position (P<0.05). Serum hs-CRP and the expression of NF-κB, IL-6 and TNF-α in the rosiglitazone treatment group and the diabetic model group was significantly higher than those in the control group (P<0.01). Compared with the diabetic model group, serum hs-CRP and the expression of NF-κB, IL-6 and TNF-α in the rosiglitazone treatment group was decreased (P<0.05). ConclusionCognitive impairment in senile diabetic rats is associated with serum hs-CRP. The cognitive function can be improved with rosiglitazone treatment. The protective mechanisms may be related to the decrease of serum hs-CRP, inhibition of NF-κB signal and down-regulation of the expression of IL-6 and TNF-α in hippocampal tissues.
ObjectiveTo explore the protective mechanism and effect of the resveratrol for kidney injury of obstructive jaundice. MethodsThe rats were randomly divided into three groups: sham operation group receiving laparotomy without bile duct ligation (BDL), the obstructive jaundice group with BDL, and the obstructive jaundice + resveratrol group given resveratrol following BDL. The levels of total bilirubin (TBIL), direct bilirubin (DBIL), blood urea nitrogen (BUN), and creatinine (Cr) in the serum were tested. The superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, glutathione (GSH) level in the renal tissues were detected. The expressions of the silent information regulator 1 (SIRT1) and nuclear factor-κB (NF-κB) proteins were tested by Western blot. The expression of SIRT1 mRNA was detected by RT-PCR and the renal cell apoptosis was examined by TUNEL staining. Results①Compared with the sham operation group, the levels of serum TBIL, DBIL, BUN and Cr were significantly higher (P < 0.05); the activity of SOD and level of GSH, and the expressions of SIRT1 mRNA and SIRT1 protein in the renal tissues were signi-ficantly lower (P < 0.05); the content of MDA, the expression of NF-κB protein, and the rate of cell apoptosis in the renal tissues were significantly higher (P < 0.05) in the obstructive jaundice group.②Compared with the obstructive jaundice group, the levels of serum TBIL, DBIL, BUN and Cr were significantly lower (P < 0.05); the activity of SOD and level of GSH, and the expressions of SIRT1 mRNA and SIRT1 protein in the renal tissues were significantly higher (P < 0.05); the content of MDA, the expression of NF-κB protein, and the rate of cell apoptosis in the renal tissues were significantly lower (P < 0.05) in the obstructive jaundice+resveratrol group. ConclusionThe resveratrol could alleviate renal damage and play a beneficial role to resist inflammation, oxidation, and apoptosis by activating the SIRT1 which probably inhibits the expression of NF-κB protein and promotes the activity of SOD in cholestatic kidney injury.
Objective To investigate the effects of glutathione S-transferase M5 (GSTM5) on the inflammation in human bronchial epithelial 16HBE cells and its possible molecular mechanisms. Methods Acute lung injury cell model was constructed with 16HBE cells induced by tumour necrosis factorα (TNF-α, 10 ng/mL). The cells were devided into a control group, a TNF-α group (TNF-α), a GSTM5 group (GSTM5+TNF-α), a negative control group (negative control plasmid+TNF-α). GSTM5-GFP plasmid and negative control plasmid were respectively transfected to the cells of the GSTM5 group and the negative control group using Lipofectamine2000. The contents of interleukin-6(IL-6), IL-8, IL-10 in the cell supernatant were measured by ELISA.The expression of nuclear factor-κB (NF-κB) mRNA was detected by RT-PCR, and the expression of NF-κB, phospho-NF-κB, p38, phospho-p38 protein were detected by Western blot. Results The GSTM5-GFP eukaryotic expression vector was successfully constructed and transfected successfully confirmed by fluorescence microscope. The contents of IL-6, IL-8, IL-10 in the TNF-α-induced cell supernatant were significantly higher than those in the control group(P < 0.05), and the contents of IL-6, IL-8, IL-10 in the GSTM5 group were lower than those in the TNF-α group (P < 0.05)with statistically significant difference. At the same time, the total NF-κB mRNA, phospho -NF-κB and phospho-p38 protein were increased in TNF-α stimulated cells compared with the control group (P < 0.05), while the GSTM5 group was lower than that in the TNF-α group and the negative control group (P < 0.05). Conclusion Overexpression of GSTM5 inhibits the phosphorylation of p38MAPK and NF-κB and down-regulates the inflammation of TNF-α-induced human bronchial epithelial 16HBE cells.
ObjectiveTo investigate the role and mechanism of P-selectin glycoprotein ligand-1 (PSGL-1) in hydrochloric acid-induced acute lung injury (ALI) in mice.MethodsWild-type mice (WT) and PSGL-1 knockout mice (PSGL-1 -/-) were randomly subjected to normal saline (NS) or hydrochloric acid (HCl) challenged group. The mice were intratracheally instilled with NS or HCl (1 μl/g weight) into the left lung with a catheter. After 2 hours, respiratory function index enhanced pause (Penh), PaO2 and PaO2 were analyzed. The wet to dry weight ratio (W/D) of the left lung and total protein concentration in bronchoalveolar lavage fluid (BALF) were measured. The number of leukocytes in BALF was counted too. Targeted lung tissue was processed for further HE or immunohistochemistry staining. Meanwhile, the expressions of interleukin-6 (IL-6), IL-1β, nuclear factor-κB (NF-κB), IκBa and p-IκBa in lung tissue were measured.ResultsThe Penh (4.77±1.22 vs. 5.80±0.84) and PaCO2 [(63.7±3.9) mm Hg vs. (74.4±7.4) mm Hg] in the PSGL-1 knockout mice were significantly lower than those in the WT mice after HCl stimulation (P<0.05), while the PaO2 was higher than that in the WT mice [(81.0±7.1) mm Hg vs. (62.0±8.9) mm Hg, P<0.05)]. The lung W/D ratio (4.86±0.15 vs. 5.22±0.20), protein concentration [(3.71±0.64) μg/μl vs. (4.74±0.98) μg/μl] and total leukocyte count [(13.00±2.18) ×107/L vs. (49.42±3.35) ×107/L] in BALF were significantly lower in the PSGL-1 knockout mice challenged with HCl than those in the WT mice (P<0.05). Besides, the protein expressions of IL-6, IL-1β, p65 and p-IκBa in the PSGL-1 knockout mice were lower than those in the WT mice after HCl instillation, while the IκBa expression was higher than that in the WT mice (P<0.05). More numbers of neutrophils and macrophages were found in the lung of the WT mice than the PSGL-1 knockout mice challenged with HCl. However, the differences of above values between the WT mice and the PSGL-1 knockout mice instilled with NS were not found, all of which were significantly lower than the correspongding HCl group except for IκBa (P<0.05).ConclusionPSGL-1 may play important roles in the development of HCl-induced ALI via the NF-κB signaling pathway and inflammation.
ObjectiveTo identify the expression functions of human NF-κBp65 nuclear localization signals' deletion mutant plasmids(namely pcDNA3.1(+)-NF-κBp65ΔNLS, NF-κBp65ΔNLS, for short) and the changes of proliferation, migration and adhesion ability of A549 lung cancer cells with low expression of NF-κBp65 (namely A549/NF-κBp65 shRNA cells). MethodsHuman A549/NF-κBp65 shRNA cells were cultivated and divided into a control group, a transfection pcDNA3.1 (+) group, and a transfection NF-κBp65ΔNLS group. Indirect immunofluorescence, real-time fluorescent quantitative PCR and Western blot techniques were used to detect the NF-κBp65 intracellular localization and the change of NF-κBp65 mRNA and protein expression level. MTT, Transwell and cell adhesion experiments were used to analyze the changes of proliferation, migration and adhesion ability of A549/NF-κBp65 shRNA cells. ResultsThe human NF-κBp65ΔNLS eukaryotic expression plasmid was successfully constructed. Compared with the control group and the transfection pcDNA3.1(+) group, NF-κBp65 mRNA expression level in A549/NF-κBp65 shRNA cells was increased in the transfection NF-κBp65ΔNLS group(10.63±0.84 vs. 1.04±0.21 and 1.23±0.22, P < 0.01) and NF-κBp65 protein expression level was also increased (1.07±0.06 vs. 0.53±0.02 and 0.59±0.04, P < 0.01). NF-κBp65 protein mainly located in the cytoplasm, and did not significantly transferred into the nucleus after stimulated by TNF-α. At the same time, A549/NF-κBp65 shRNA cells' proliferation, migration and adhesion ability were enhanced compared with the control group and the transfection pcDNA3.1(+) group. ConclusionsThrough gene mutation technology to build the human NF-κBp65ΔNLS eukaryotic expression plasmid and transfect into A549/NF-κBp65 shRNA lung cancer cell lines, both mRNA and protein expression levels of NF-κBp65 were increased significantly, and NF-κBp65 protein mainly located in the cytoplasm. The overexpressed NF-κBp65 in cytoplasm can obviously enhance the A549/NF-κBp65 shRNA cell's proliferation, migration and adhesion ability. It suggests that NF-κBp65 stranded in the cytoplasm can still regulate biological behavior of lung cancer cells by influencing the NF-κB signaling pathway related proteins.
Objective To investigate the transduction pathway of TREM-1 during endotoxininduced acute lung injury ( ALI) in mice through the specific activating or blocking TREM-1.Methods 40 mice were randomly divided into a saline control group, an ALI group, an antibody group, and a LP17 group ( 3.5 mg/kg) . All mice except the control group were intraperitoneally injected with lipopolysaccharide ( LPS) to establish mouse model of ALI. Two hours after LPS injection, anti-TREM-1mAb ( 250 μg/kg) was intraperitoneally injected in the antibody group to activation TREM-1, and synthetic peptide LP17 was injected via tail vein in the LP17 group to blocking TREM-1. After 6,12,24, 48 hours, 3 mice in each group were sacrificed for sampling. The expression of NF-κB in lung tissue was determined by immunohistochemistry. The levels of TNF-α, IL-10, TREM-1, and soluble TREM-1 ( sTREM-1) in lung tissue and serumwere measured by ELISA. Pathology changes of lung were observed under light microscope, and Smith’s score of pathology was compared. Results Administration of anti-TREM-1mAb after ALI modeling significantly increased the NF-κB expression in lung tissue at 48h, resulting in a large number of pro-inflammatory cytokines releasing in the lung tissue and serumand lung pathology Smith score increasing. Administration of LP17 after modeling significantly down-regulated the expressions of NF-κB and pro-inflammatory cytokines, while led to a slight increase of anti-inflammatory cytokines and a decline of lung pathology Smith’s score.Conclusion TREM-1 may involve in inflammatory response by promoting the generation of inflammatory factors via NF-κB pathway, thus lead to lung pathological changes in ALI.