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.
Abstract: Objective To study the preventive effect of n-3 polyunsaturated fatty acids on allograft arteriosclerosis. Methods Arterial homeotransplant model were created with 480 rats which were divided into four groups. Control group, no n-3 lyunsaturated fatty acids were taken. Group A, n-3 polyunsaturated fatty acids were taken for two weeks before operation with the dose of EPA 600mg/kg. Group B, 300 mg/kg and group C 150 mg/kg were taken respectively. The recipient’s transplanted vessel was excised after 1,7,14,21and 28 days respectively. The tissue pathological variations, ultrastructure variations and expression variations of intercellular adhesion molecule-1(ICAM-1), vascular cell adhesion molecule-1（VCAM-1）, nuclear factorkappa B（NF-κB） had been observed. Results The pathological changes occurred 7 days after operation in control group and were most prominent on the 28th day, blood vessels were obstructed and the expressions of ICAM-1, VCAM1,NF-κB were markedly intensified than those of group A, B, C (Plt;0.05). The pathological variations of transplanted vessel in group A, B, C occurred later than those in control group. The nonobstruction rates in group A, B, C were better than that in control group. The expressions of ICAM-1， VCAM-1， NF-κB in control group were ber than those in group A， B， C (Plt;0.05). The expressions of ICAM-1， VCAM-1， NF-κB after 1 day or 7 days demonstrated no statistically significant change in group A， B， C （Pgt;0.05）. The preventive effect for allograft vessel atheromatosis in group A and group B was ber than that in group C after 14, 21 and 28d (Plt;0.05). There were no significant difference between group A and group B (Pgt; 0.05). Conclusion The n-3 polyunsaturated fatty acids can prevent the allograft vessel atheromatosis, the most effective dose of n-3 polyunsaturated fatty acids is 300 mg/kg.
Objective To investigate the expression changes of nuclear factor kappa B (NF-κB) and matrix metalloproteinase-9 (MMP-9) in the cultured hepatocellular carcinoma cells 9204 (HCC9204) transfected with inhibitory kappa B alpha（IκB-α)vector. Methods After pcDNA3-IκB-α vector and pcDNA3 were transfected into HCC9204 by lipofectamine method, Western-blot and RT-PCR analysis were used to detect the expressions of NF-κB and MMP-9. Migration and invasion of tumor cells were assayed by fundus membrane invaded by them. Results When pcDNA3-IκB-α was transfected into HCC9204, the expression of NF-κB was decreased at the protein level, and the expression of MMP-9 mRNA and the invision and metastasis ability of transfected cells were obviously decreased. Conclusion When the activity of NF-κB is inhibited, the ability of invasion and metastasis in HCC9204 cells decrease, which could be related to the decreased the expression of MMP-9.
ObjectiveTo investigate the effect of Metformin (MET) on the anxiety behavior of mice with Pentylenetetrazol (PTZ)-induced epilepsy and the mechanisms. MethodsSixty male 8-week-old C57BL/6 mice were randomly divided into normal control group (Normal), Temporal lobe epilepsy (TLE) model control group (TLE-con), TLE + MET treatment group (TLE-MET), and normal mice + MET intervention group (MET-con) (n=15/group). In the TLE-con group and the TLE-MET group, mice were injected intraperitoneally with PTZ every other day to establish the TLE model, while mice in the Normal group and the MET group were given the same dose of normal saline. During PTZ administration, mice in the TLE-MET treatment group and the MET-con group were intraperitoneally injected with MET at 200 mg/(kg·d) every other day, for 14 times in a total of 28 days. The mice in the Normal group and the TLE-con group were intraperitoneally injected with the same amount of normal saline. Open field test (OFT) and elevated cross maze (EPM) were used to evaluate the anxiety behavior of mice in each group, and the Western blotting analysis was performed to detect expression of Toll like receptor 4 (TLR4), Nuclear factor-kappa B (NF-κB) p65 in brain tissues. ResultsCompared with the Normal group, the TLE-con group showed decreased times in the open arm in the EPM test (P<0.01) and in the center of open field in the OFT test (P<0.01), while MET intervention could increase the times of epileptic mice in the central area and the open arm (P<0.05). Compared with the Normal group, the expression of TLR4 and NF-κB in the cerebral cortex in the TLE-con group was increased significantly (P<0.05), while MET intervention could partially decrease the expression of TLR4 and NF-κB in the cerebral cortex of epileptic mice (P<0.05). ConclusionMET may improve the anxiety behavior of epileptic mice by reducing the inflammatory TLR4–NF-κB pathway.
Objective To observe the effects of exogenous pulmonary surfactant (PS) on ventilation-induced lung injury (VILI) in rats, and to investigate its possible mechanisms. Methods A total of 40 Wistar rats were divided into 4 groups with randomized blocks method: control group, high tidal volume (HV) group, VILI group, and PS group, with 10 rats in each group. The control group was subjected to identical surgical procedure but was never ventilated. After 30 min of mechanical ventilation (MV) with Vt 45 ml/kg, the rats in HV group were killed immediately; rats in the VILI group were continually ventilated for up to 150 min with Vt 16 ml/kg; in the PS group, 100 mg/kg of PS administered intratracheally and with the same settings as VILI group. Mean artery pressure (MAP), blood gas analysis, lung wet to dry weight ratios (W/D), thorax-lung compliance, and cell counts in bronchoalveolar lavage fluid (BALF) were determined. Nuclear factor-κB(NF-κB) activity in lungs was measured by enzyme-linked immunosorbent assay (ELISA), interleukin-8(IL-8) in serum and BALF was determined by radioimmunoassay (RIA). Pathological examination of the lung was performed. Results Injurious ventilation significantly decreased MAP and PaO2/FiO2, but increased NF-κB activity and W/D. MAP and PaO2/FiO2 improved, but NF-κB activity, IL-8 in serum and BALF, and cell counts in BALF reduced significantly in PS group compared with those in VILI group. Histological studies showed reduced pulmonary edema and atelectasis in the PS group. Conclusion PS administered intratracheally can suppress the increased activity of NF-κB induced by VILI, exogenous PS can be used to treat VILI.
Objective To observe the protective effects of unfractionated heparin (UFH) on high-mobility group box-1 protein (HMGB1) induced increased permeability of endothelial cells, and investigate the protective mechanism of UFH on HMGB1 induced defective expression of zonula occludens-1 (ZO-1). Methods Human umbilical vascular endothelial cells (HUVECs) were culturedin vitro and divided into 4 groups (n=5), namely a control group, a HMGB1 group (100 ng/ml), a heparin group (UFH 10 U/ml), a HMGB1/heparin group (100 ng/ml HMGB1 + UFH 10 U/ml). Endothelial cell viability was measured by methyl thiazolyl tetrazolium (MTT) colorimetric method. Endothelial permeability was determination by Transwell chamber method. Immunofluorescence and laser confocal microscopy were used to assess the distribution of ZO-1. The protein expressions of tight junction protein ZO-1 and nuclear factor kappa B (NF-κB) were detected by Western blot. Results HMGB1 (100 ng/ml) had no inhibitory effect on endothelial cell viability (P＞0.05). UFH pretreatment could reduce the permeability increment of endothelial cells induced by HMGB1. UFH pretreatment could reduce the close loop reduction and damage of ZO-1 induced by HMGB1, enhance the fluorescence intensity and expression of ZO-1, and decrease the NF-κB translocation. Conclusions UFH can protect HMGB1-mediated defect of ZO-1 expression and increased permeability of the endothelial cells. The mechanism may be related to the decreased nuclear translocation of NF-κB.
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.
【 Abstract 】 Objective Overexpressions of epidermal growth factor (EGF) and EGF receptor have been associated with progression and invasive phenotype of pancreatic cancer. However, the underlying molecular mechanism by which EGF worked in pancreatic cancer cells has not been completely understood. In this study, effect of EGF on the invasion and metastasis of pancreatic cancer cells and its regulatory mechanism were investigated. Methods The effects of EGF on the proliferation, adhesion and invasion of pancreatic cancer cells were detected by WST-1 proliferation assay, adhesion assay and invasive assay, respectively. The activity and expression of MMP-2 and MMP-9 were examined by zymography, Western blot and RT-PCR, respectively. The activity of NF- κ B was examined by EMSA. Results EGF could significantly promote the invasiveness of pancreatic cancer cells but did not affect cell proliferation or adhesion. The expressions of NF- κ B and MMP-9 were significantly increased by EGF, but EGF did not affect the activity and expression of MMP-2. Furthermore, EGF stimulated the NF- κ B binding activity. Pretreatment with NF- κ B inhibitors, pyrrolidine dithiocarbamate (PDTC), could significantly inhibit the activity of NF- κ B induced by EGF. Meanwhile, the EGF-induced expression and activity of MMP-9, as well as cell invasiveness were also inhibited by NF- κ B inhibitor. Conclusion EGF could increase the expression and promote the invasiveness of MMP-9 via the activation of NF- κ B in pancreatic cancer cells, which implies that NF- κ B inhibitant, such as PDTC, may diminish the invasiveness of pancreatic cancer cells.
Objective To investigate the effects of nuclear factor kappa B decoy oligodeoxynucleotides ( NF-κB decoy ODN) transfection on biological characteristics of mature dendritic cells ( mDCs) in mice. Methods Immature DCs were harvested from Balb / c mice bone marrow, followed by the incubation with antigen OVA and LPS, and mature DCs were evaluated by the expressions of CD11c and MHC-Ⅱ detected by FACS. Mature DCs were transfected with NF-κB decoy ODN and the changes of NF-κB activity after the transfection were detected by EMSA. The expressions of the costimulatory molecules( CD40,CD80 and CD86) on DCs were detected by FACS and the proliferation of T cells was tested by mixed lymphocyte reaction( MLR) . Results The mature DCs were cultured successfully. The NF-κB activity of NF-κB decoy ODN transfected DCs was decreased significantly( P lt; 0. 05) . There was no difference in the expressions of CD40 and CD80, but the expression of CD86 was decreased significantly in NF-κB decoy ODN transfection group( P lt; 0. 05) . MLR test showed that the proliferation of T lymphocyte cells was inhibited by NF-κB decoy ODN transfected DCs, but was stimulated bly by the DCs of other groups. Conclusions Mature DCs transfected with NF-κB decoy ODN could inhibit the proliferation and activation of antigenspecical T cells, which was probably related to the down-regulation of CD86 on DCs. This modified DCs might be a promising vaccine for the treatment of asthma in the future.
Vascular smooth muscle cells (VSMCs) phenotype switching plays an essential role in the pathogenesis of various vascular diseases. The present study aims to investigate the role of receptor-interacting protein kinases 1(RIPK1) in VSMCs phenotypic switching induced by Angiotensin Ⅱ(Ang Ⅱ). Expression of mRNA and protein of RIPK1, markers of VSMCs phenotypic switching and secretion, phosphorylation of the P65 subunit of NF-κB were measured by real-time PCR and Western blot. Meanwhile, EdU incorporation assay and wound scratch assay were performed to determine the cell proliferation and migration respectively. At the same time, Necrostatin-1(Nec-1, an known RIPK1 inhibitor) and RIPK1-specific small interference RNA (siRNA) were used to inhibit the expression of RIPK1. The experimental data demonstrated that the mRNA and protein levels of RIPK1 and P65 phosphorylation were increased significantly in the process of VSMC phenotypic switching induced by Ang II. Moreover, the expression of RIPK1 and P65 phosphorylation were significantly down-regulated in VSMCs pretreated with Nec-1 or trans-fected with RIPK1-siRNA. Furthermore, the proliferation, secretion and migration of VSMCs were also markedly suppressed after inhibition of RIPK1 by Nec-1 or its specific siRNA. The results suggested that RIPK1 might be involved in VSMC phenotypic switching induced by Ang II, which was possibly via up-regulating the NF-κB signaling pathway.