Objective To explore the effect on apoptotic genes of pancreatic adenocarcinoma cell BxPC-3 from subcutaneous transplantation tumor in nude mice induced by 5-FU and sulfasalazine (SZ).Methods Changes of apoptosis-related genes 〔bcl-2, cyclinD1, Bax and NF-κB (p65)〕 in subcutaneous transplantation tumor treated by 5-FU, SZ alone or both at the levels of mRNA and protein were measured by RT-PCR and Western blot. Results NF-κB (p65) at mRNA relative content and protein expression in subcutaneously heterotopic transplantation tumor treated by 5-FU (7.5, 15 mg/kg), SZ (10, 20 mg/kg) alone or both showed significant difference, except for two subsets in SZ group, respectively, in comparison with each control group (P＜0.01). Meanwhile bcl-2 and cyclinD1 at the levels of mRNA and protein, and Bax protein level were significantly different from each control group (P＜0.01). The above-mentioned indexes were show obvious interaction of both by multiple factor analysis of variance. Conclusion Up-regulated level of Bax, down-regulated levels of bcl-2, cyclinD1 and NF-κB (p65) might be one of apoptotic mechanisms that SZ synergistically enhanced apoptotic effect on pancreatic adenocarcinoma cell BxPC-3 of subcutaneous transplantation tumor in nude mice induced by 5-FU.
Objective To investigate the expressions of ubiquitin-proteasome markers，including E2-14K，MAFbx，MuRF-1，and nuclear factor-κB（NF- κB） p50，in diaphragm of COPD rats，and their relationship with IL-17 level in diaphragm and serum in order to elucidate the potential mechanism of diaphragm atrophy. Methods Thirty healthy adult male SD rats were randomly divided into a model group （n=18） and a normal control group （n=12）. The COPD rat model was established by instillation of lipopolysaccharide （LPS） and exposure to cigarette smoke for 28 days. The protein levels of E2-14K，MAFbx，MuRF-1，and NF-κB p50 in diaphragm were measured by Western blot. The concentration of IL-17 in serum and diaphragm was measured by ELISA. Results Western blot showed that the protein expressions of E2-14K，MAFbx，MuRF-1，and NF-κB p50 in diaphragm increased significantly in the COPD model group compared with the normal control group （0.96±0.12 vs. 0.53±0.09，0.99±0.10 vs. 0.53±0.08，0.95±0.08 vs. 0.51±0.16，1.11±0.10 vs. 0.64±0.50，respectively，Plt;0.01）. The IL-17 level in serum and diaphragm was significantly higher in the COPD group than the control group. The expression of NF-κB p50 was positively correlated with E2-14K，MAFbx，and MuRF-1 expressions （r=0.82，0.92，0.86，respectively，Plt;0.01）. Both in serum and diaphragm，IL-17 level was positively correlated with the percentage of neutrophils，levels of NF-κB p50，E2-14K，MAFbx，and MuRF-1 expressions（all Plt;0.01）. The IL-17 levels in serum and diaphragm were also positively correlated each other （r=0.84，Plt;0.01）. Conclusions The results show that the ubiquitin-proteasom pathway，the NF-κB pathway and IL-17 are up-regulated in diaphragm of COPD rats .These alterations may contribute to diaphragm atrophy in COPD.
Objective To observe the effect of epidermal growth factor (EGF) on the proliferation, adhesion, invasiveness and the activation of nuclear factor-κB (NF-κB), matrix metalloproteinases (MMPs) expression and explore related mechanisms in pancreatic cancer cells. Methods Cell invasion assay, proliferation assay and adhesion assay were used to examine the proliferation, adhesion and invasiveness of pancreatic cancer cells, respectively. NF-κB activity was detected by electrophoretic mobility shift assay (EMSA), and MMPs protein and mRNA expressions were investigated by gelatin zymography, Western blot and reverse transcriptase-polymerase chain reaction (RT-PCR). Results EGF increased the invasiveness of pancreatic cancer cell in a dose-dependent manner (P＜0.05), but did not affect cell proliferation or adhesion. The expressions of MMP-9 mRNA and protein significantly increased after induction by EGF and were highest when EGF concentration was 50 ng/ml, while there was no effect on the expressions of MMP-2 mRNA and protein. Furthermore, NF-κB activity increased with increased concentration of EGF in a concentration-dependent manner (P＜0.05). In addition, NF-κB activity and the expressions of MMP-9 mRNA and protein by pretreatment with both pyrrolidine dithiocarbamate (PDTC) and EGF decreased when compared that by pretreatment with EGF alone. The invasiveness of pancreatic cancer cell by pretreatment with both PDTC and EGF decreased when compared that by pretreatment with EGF alone and nothing (P＜0.05).Conclusion The findings indicate that the NF-κB-mediated MMP-9 induction is essential for EGF-induced invasiveness in pancreatic cancer cells, which can be inhibited by PDTC.
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.
Objective To construct the mouse NF-κB P65 subunit expression plasmid, and identify its biological activity. Methods NF-κB P65 siRNA retrovirus expression vectors were reconstructed by molecular clone technology. Recombinant vectors were transfected into 293E package cells and virus suspension was collected. RT-PCR was used to detect the expression level of NF-κB P65 mRNA and TNF-α mRNA at different time-point of LPS stimulation. Western blot was performed to analyze the protein level of NF-κB P65. ELISA was applied to detect the expression level of TNF-α released by LPS-stimulated J774A.1. Results NF-κB P65 siRNA retrovirus expression vectors of mouse were successfully constructed. From2 hours after the stimulation of LPS, the expression level of NF-κB P65 mRNA of the siRNA group was obviously lower than the scramble control group ( 0.91 ±0.03 vs. 1.02 ±0.02, Plt;0.01) . At24,36, 48 and 72 hours after the LPS stimulation, the expression level of NF-κB P65 protein of the siRNA group was significantly decreased compared with the scramble control group ( 0.97 ±0.02 vs. 1.01 ±0.01, 0.94 ± 0.01 vs. 1.02 ±0. 01,0.94 ±0.02 vs. 1.02 ±0.01, 0.93 ±0.01 vs. 1.00 ±0.02, Plt;0. 05) . At 2, 6, 12, 24 hours after the LPS stimulation, both the expression level of TNF-α mRNA and the content of TNF-α in the culture medium supernatant of the siRNA group were lower than the scramble control group ( Plt;0. 01) . Conclusions The construction of NF-κB P65 siRNA retrovirus expression vectors is feasible. Inflammation factors in mouse monocyte-macrophages are significantly inhibited after NF-κB expression is depressed by RNA interference technology, which may be applied to prevent and treat excessive inflammatory reaction in acute lung injury.
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.
ObjectiveTo explore the mechanism of lung injury in Sprague-Dawley (SD) rats induced by acute organic phosphorus pesticides (AOPP) by observing the changes of the blood serum nuclear factor (NF)-κB consistence, NF-κB level of lung tissue and lung coefficient. MethodNinety-six healthy male SD rats (six weeks old) were randomly divided into group A (control, n=48) and group B (poison, n=48). The rats of group B were given omethoate by gavage (45 mg/kg), and the rats of group A accepted normal saline. Then the rats were killed at designated observing points (30 minutes; 3, 6, 12, 24, and 48 hours), and the lung coefficient, blood serum NF-κB consistence and NF-κB level of lung tissue were measured. At the same time, we observed the pathological changes of the rats' lung tissue. ResultsCompared with group A, blood serum NF-κB consistence, NF-κB level of lung tissue and the level of lung coefficient in group B were significantly higher (P<0.01). The lung tissues of group A were normal at each time point, but in group B, the lung pathological changes gradually appeared 30 minutes later with pulmonary interstitial engorging, alveolar septum widening and some alveolus being full of red blood cells, and this situation reached its peak at hour 12. Then it gradually mitigated from 24 to 48 hours. ConclusionThere are significant increases in blood serum NF-κB consistence and NF-κB level in lung tissues in rats with lung injury induced by omethoate poisoning. The NF-κB may play a role in the process of lung injury induced by organophosphorus pesticide.
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.
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.
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.