【 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.
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.
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 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.
Behcet's Disease (BD) is a multisystem vasculitis characterized by disease alternated with recurrent episodes and remissions, involving genital, oral, ocular uvea, cutaneous, and articular manifestations. The nuclear factor (NF)-κB signaling pathway paly an important role in the BD progression. It encompasses diverse gene, protein, and cellular regulatory mechanisms operating across various levels, alongside microbiological and experimental studies involving animals and cells. At the protein research findings, activation of the NF-κB pathway in BD patients is marked by elevated plasma levels of soluble CD40 ligand, which stimulates neutrophils to release reactive oxygen species and extracellular traps, thereby promoting inflammation. At the cellular research findings, macrophages in BD patients polarize towards classically activated macrophages phenotype through the NF-κB pathway, exacerbating the inflammatory response. The activation of NF-κB is associated with increased expression of anti-apoptotic proteins in T cells, leading to prolonged inflammation. Microbiological investigations reveal that the decreased gut microbiota diversity in BD patients compromises intestinal barrier integrity. NF-κB pathway involvement in regulating neutrophil and type 1 helper T cell (Th) 1/Th17 cell function worsens inflammation. Genetically, BD patients exhibit polymorphisms in immune regulatory genes, which contribute to inflammation through the NF-κB pathway. Mutations in NF-κB-associated genes elevate the risk of BD, while mutations in the endogenous inhibitor A20 lead to abnormal NF-κB activity, sustaining inflammation. Animal experiments and in vitro experiments corroborate the efficacy of NF-κB inhibitors in attenuating inflammation. Targeting upstream inflammatory factors within the NF-κB pathway yields positive outcomes in BD patients. In summary, the NF-κB signaling pathway plays a pivotal role in the development of BD. Developing NF-κB inhibitors may open new avenues for treating BD. Further research is necessary to comprehensively elucidate the precise mechanisms by which NF-κB operates in the pathogenesis of BD, as well as its potential clinical applications in therapy.
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 study the expression of nuclear factor-κBp65 (NF-κBp65) in gastric carcinoma and its relationship with vascular endothelial growth factor (VEGF). Methods The expression of NF-κBp65 and VEGF in 56 gastric carcinomas was detected with immunohistochemistry and compared with benign tissues. Results The positive rates of NF-κBp65 and VEGF in 56 gastric carcinomas were 62.5% and 76.8% respectively,and which were higher than those of gastric mucosal atypical hyperplasia (33.3% and 44.4%) and the normal gastric mucosa(0 and 8.3%) （P＜0.05,P＜0.01）.It was found that there was relationship between the expression of NF-κBp65 and the clinical stage, invasion depth of tumor and lymph node metastasis (P＜0.05),but there was no relation to the historica type (Pgt;0.05). There was positive correlation between NF-κBp65 and VEGF expression （r=0.36,P＜0.01）. Conclusion NF-κBp65 may play an important role in the development of gastric carcinoma by up-regulate the expression of VEGF.
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.
Objective To explore effects of macrophage migration inhibitory factor (MIF) inhibitor ISO-1 on intestinal injury in acute necrotic pancreatitis in pregnancy (ANPIP) rat. Methods Twenty-four pregnant SD rats were randomly averagely divided into three groups: a sham operation (SO) group, an ANP group, and an ANP model plus ISO-1 treatment group (ISO-1 group). A rat model of ANP was induced by the retrograde injection of 5% sodium taurocholate into the biliopancreatic duct. The rats were killed and the inferior vena cava blood and the tissues of pancreas and jejunum were harvested at 12 h after the operation. The serum amylase (AMY), lipase (LIP), diamine oxidase (DAO), interleukin (IL)-1β, and IL-6 levels were measured. The pancreatic and jejunal tissues were taken for the pathological examination scoring. The immunohistochemical method was used to detect the expression of the MIF, nuclear factor (NK)-κB, or tumor necrosis factor (TNF)-α protein. Results ① Compared with the SO group, the serum AMY, LIP, DAO, IL-1β, and IL-6 levels were increased in the ANP group (P<0.050), which in the ISO-1 group were decreased as compared with the ANP group, the DAO, IL-1β, and IL-6 levels had significant differences (P<0.050), but the AMY and LIP levels had no significant differences (P>0.050). ② The pathological points of the pancreas and jejunum tissues were increased in the ANP group as compared with the SO group, which were significantly decreased in the ISO-1 group as compared with the ANP group (P<0.050). ③ The average integrated optical density divide by area of the NF-κB,TNF-α, and MIF were significantly increased in the ANP group as compared with the SO group, which were significantly decreased in the ISO-1 group as compared with the ANPgroup (P<0.050). Conclusions MIF inhibitor ISO-1 could protect intestinal injury in ANPIP rat. It is suggested that MIF is one of mechanisms in ANPIP with intestinal injury and might be correlated with activities of TNF-α and NF-κB.
Objective To investigate influence of genders on the activity of nuclear factor-kappa B (NF-κB) in lungs of endotoxemic rats. Methods Twenty female and 20 male Wistar rats were randomly divided into four groups as follow: female control group (n=10), male control group (n=10), male endotoxemic group (n=10), and female endotoxemic group (n=10). The endotoxemic rats model was made by injecting lipopolysaccharide (5 mg/kg) into the abdominal cavity. Tissue samples were collected from the lungs in different groups and electrophoresis mobility shift assay was used to measure the activity of NF-κB. The levels of serum TNF-α and estrogen were measured at the same time. Results There was no significant difference between the activities of NF-κB in male and female control groups (1.33±0.24 vs 1.47±0.40）, and there was also no significant difference between other items in these groups as well (Pgt;0.05). Yet, the activity of NF-κB (female: 12.10±2.89; male: 19.53±2.12) and the level of TNF-α 〔female: (4.10±0.72) ng/ml; male: (6.37±1.29) ng/ml〕 were significantly increased after injection of lipopolysaccharide (Plt;0.01), and the indices in female group were significantly lower than those in male group (Plt;0.01). Correlation analysis showed that there was a positive relation between the activity of NF-κB in lungs and the level of TNF-α (female: r=0.921 1, P=0.013; male: r=0.907 2, P=0.017), and there was a negative correlation between the activity of NF-κB and the level of estrogen (female: r=-0.887 5, P=0.017; male: r=0.872 3, P=0.022) in both male endotoxemic group and female endotoxemic group (Plt;0.05). Conclusion Gender may be one of the factors that influence the activity of NF-κB in the lungs of endotoxemic rats. While on the other hand, endogenous estrogen may protect the lungs of endotoxemic rats from injury by inhibiting the activity of NF-κB.