BACKGROUND: The active form of nuclear factor-kappa B (NF-kappa B) is involved in the initiation, generation, and development of hepatocellular carcinoma (HCC), and is up-regulated in inflammation-associated malignanc...BACKGROUND: The active form of nuclear factor-kappa B (NF-kappa B) is involved in the initiation, generation, and development of hepatocellular carcinoma (HCC), and is up-regulated in inflammation-associated malignancies. We investigated the dynamic expression of NF-kappa B and its influences on the occurrence of HCC through antiangiogenic (thalidomide) intervention in NF-kappa B activation. METHODS : Hepatoma models were induced with 2-fluorenylacetamide (2-FAA, 0.05%) in male Sprague-Dawley rats, and thalidomide (100 mg/kg body weight) was administered intragastrically to intervene in NF-kappa B activation. The pathological changes in the liver of sacrificed rats were assessed after hematoxylin and eosin staining. NF-kappa B mRNA was amplified by RT-nested PCR. The alterations of NF-kappa B and vascular endothelial growth factor (VEGF) expression were analyzed by enzyme-linked immunosorbent assay, immunohistochemistry, and Western blotting. RESULTS: Rat hepatocytes showed denatured, precancerous, and cancerous stages in hepatocarcinogenesis, with an increasing tendency of hepatic NF-kappa B, NF-kappa B mRNA, and VEGF expression, and their values in the HCC group were higher than those in controls (P<0.001). In the thalidomide-treated group, the morphologic changes generated only punctiform denaturation and necrosis at the early or middle stages, and nodular hyperplasia or a little atypical hyperplasia at the final stages, with the expression of NF-kappa B (chi(2)=9.93, P<0.001) and VEGF (chi(2)=8.024, P<0.001) lower than that in the 2-FAA group. CONCLUSION: NF-kappa B is overexpressed in hepatocarcinogenesis and antiangiogenic treatment down-regulates the expression of NF-kappa B and VEGF, and delays the occurrence of HCC. (Hepatobiliary Pancreat Dis Int 2010; 9: 169-174)展开更多
BACKGROUND: Urinary trypsin inhibitor (UTI) inhibits the inflammatory response and protects against ischemia-reperfusion (I/R) injury. The inflammatory response is mediated by nuclear factor-kappa B (NF-kappa B) and i...BACKGROUND: Urinary trypsin inhibitor (UTI) inhibits the inflammatory response and protects against ischemia-reperfusion (I/R) injury. The inflammatory response is mediated by nuclear factor-kappa B (NF-kappa B) and its related target genes and products such as vascular endothelial cell adhesion molecule and CXC chemokines. We aimed to assess the roles of those mediators in a UTI-treated mouse model of hepatic I/R injury. METHODS: Treatment group 1 (UTI given 5 minutes prior to liver ischemia), treatment group 2 (UTI given 5 minutes after the anhepatic phase) and a control group were investigated. Blood and liver samples were obtained and compared at 1, 3, 6 and 24 hours after reperfusion. RESULTS: Attenuation of pathological hepatocellular damage was greater in the treatment groups than in the control group (P < 0.05). Compared with the control group, the UTI treatment groups showed significantly lower serum alanine aminotransferase and aspartate aminotransferase levels, decreased myeloperoxidase activity, and reduced NF-kappa B activation. Also downregulated was the expression of tumor necrosis factor-alpha, cytokine-induced neutrophil chemoattractant, and macrophage inflammatory protein-2 at the mRNA level. P-selectin protein and intercellular adhesion molecule-1 protein expression were also downregulated. In addition, the treatment group I showed a better protective effect against I/R injury than the treatment group 2. CONCLUSIONS: UTI reduces NF-kappa B activation and downregulates the expression of its related mediators, followed by the inhibition of neutrophil aggregation and infiltration in hepatic I/R injury. The protective role of UTI is more effective in prevention than in treatment.展开更多
AIM: Nuclear factor kappa B (NF-κB) regulates a large number of genes involved in the inflammatory response to critical illnesses, but it is not known if and how NF-κB is activated and intercellular adhesion molecul...AIM: Nuclear factor kappa B (NF-κB) regulates a large number of genes involved in the inflammatory response to critical illnesses, but it is not known if and how NF-κB is activated and intercellular adhesion molecule-1 (ICAM-1)expressed in the gut following traumatic brain injury (TBI).The aim of current study was to investigate the temporal pattern of intestinal NF-κB activation and ICAM-1expression following TBI.METHODS: Male Wistar rats were randomly divided into six groups (6 rats in each group) including controls with sham operation and TBI groups at hours 3, 12, 24, and 72, and on d 7. Parietal brain contusion was adopted using weight-dropping method. All rats were decapitated at corresponding time point and mid-jejunum samples were taken. NF-κB binding activity in jejunal tissue was measured using EMSA. Immunohistochemistry was used for detection of ICAM-1 expression in jejunal samples.RESULTS: There was a very low NF-κB binding activity and little ICAM-1 expression in the gut of control rats after sham surgery. NF-κB binding activity in jejunum significantly increased by 160% at 3 h following TBI (P<0.05 vs control), peaked at 72 h (500% increase)and remained elevated on d 7 post-injury by 390% increase. Compared to controls, ICAM-1 was significantly up-regulated on the endothelia of microvessels in villous interstitium and lamina propria by 24 h following TBI and maximally expressed at 72 h post-injury (P<0.001). The endothelial ICAM-1 immunoreactivity in jejunal mucosa still remained strong on d 7 post-injury. The peak of NF-κB activation and endothelial ICAM-1 expression coincided in time with the period during which secondary mucosal injury of the gut was also at their culmination following TBI.CONCLUSION: TBI could induce an immediate and persistent up-regulation of NF-κB activity and subsequent up-regulation of ICAM-1 expression in the intestine.Inflammatory response mediated by increased NF-κB activation and ICAM-1 expression may play an important role in the pathogenesis of acute gut mucosal injury following TBI.展开更多
AIM: To investigate the effect of different dietary fatty acids on hepatic inflammasome activation.METHODS: Wild-type C57BL/6 mice were fed either a high-fat diet or polyunsaturated fatty acid(PUFA)-enriched diet. Pri...AIM: To investigate the effect of different dietary fatty acids on hepatic inflammasome activation.METHODS: Wild-type C57BL/6 mice were fed either a high-fat diet or polyunsaturated fatty acid(PUFA)-enriched diet. Primary hepatocytes were treated with either saturated fatty acids(SFAs) or PUFAs as well as combined with lipopolysaccharide(LPS). The expression of NOD-like receptor protein 3(NLRP3) inflammasome, peroxisome proliferator-activated receptor-γ and nuclear factor-kappa B(NF-κB) was determined by real-time PCR and Western blot. The activity of Caspase-1 and interleukine-1β production were measured.RESULTS: high-fat diet-induced hepatic steatosis was sufficient to induce and activate hepatic NLRP3 inflammasome. SFA palmitic acid(PA) directly activated NLRP3 inflammasome and increased sensitization to LPS-induced inflammasome activation in hepatocytes. In contrast, PUFA docosahexaenoic acid(Dh A) had thepotential to inhibit NLRP3 inflammasome expression in hepatocytes and partly abolished LPS-induced NLRP3 inflammasome activation. Furthermore, a highfat diet increased but PUFA-enriched diet decreased sensitization to LPS-induced hepatic NLRP3 inflammasome activation in vivo. Moreover, PA increased but Dh A decreased phosphorylated NF-κB p65 protein expression in hepatocytes.CONCLUSION:Hepatic NLRP 3 inflammasome activation played an important role in the development of non-alcoholic fatty liver disease. Dietary SFAs and PUFAs oppositely regulated the activity of NLRP3 inflammasome through direct activation or inhibition of NF-κB.展开更多
BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. We analyzed the expression of miclear-transcription factor-kappa B (NF-kappa B) during hepatocarcinogenesis in order to evaluate i...BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. We analyzed the expression of miclear-transcription factor-kappa B (NF-kappa B) during hepatocarcinogenesis in order to evaluate its dynamic expression and its clinical value in the development and diagnosis of HCC. METHODS: Hepatoma models were induced by oral administration of 2-acetamidoflurene (2-FAA) to male Sprague-Dawley rats. Morphological changes were observed after hematoxylin and eosin staining. The cellular distribution of NF-kappa B expression during different stages of cancer development was investigated by immunohistochemistry, and the level of NF-kappa B expression in liver tissues was quantitatively analyzed by ELISA. The gene fragments of hepatic NF-kappa B were amplified by nested-polymerase chain reaction assay. RESULTS: Hepatocytes showed vacuole-like degeneration during the early stages, then had a hyperplastic nodal appearance during the middle stages, and finally progressed to tubercles of cancerous nests with high differentiation. The NF-kappa B-positive material was buff-colored, fine particles localized in the nucleus, and the incidence of NF-kappa B-positive cells was 81.8% in degeneration, 83.3% in precancerous lesions, and 100% in cancerous tissues. All of these values were higher than those in controls (P<0.01). Hepatic NF-kappa B expression and hepatic NF-kappa B-mRNA were also higher during the course of HCC development (P<0.01). CONCLUSION: The NF-kappa B signal transduction pathway is activated during the early stages of HCC development, and its abnormal expression may be associated with the occurrence of HCC.展开更多
AIM: To investigate the role of p38 mitogen-activated protein kinase (p38MAPK) in murine experimental autoimmune hepatitis (EAH). METHODS: To induce EAH, the syngeneic S-100 antigen emulsified in complete Freud's ...AIM: To investigate the role of p38 mitogen-activated protein kinase (p38MAPK) in murine experimental autoimmune hepatitis (EAH). METHODS: To induce EAH, the syngeneic S-100 antigen emulsified in complete Freud's adjuvant was injected intraperitoneally into adult male C57Bl/6 mice. Liver injury was assessed by serum ALT and liver histology. The expression and activity of p38 MAPK were measured by Western blot and kinase activity assays. In addition, DNA binding activities of nuclear factor kappa B (NF-κB) were analyzed by electrophoretic mobility shift assay. The effects of SB203580, a specifi c p38 MAPK inhibitor, on liver injuries and expression of proin? ammatory cytokines (interferon-γ, IL-12, IL-1β and TNF-α) were observed. RESULTS: The activity of p38 MAPK and NF-κB was increased and reached its peak 14 or 21 d after the fi rst syngeneic S-100 administration. Inhibition of p38 MAPK activation by SB203580 decreased the activation of NF-κB and the expression of proin? ammatory cytokines. Moreover, hepatic injuries were improved significantly after SB203580 administration. CONCLUSION: p38 MAPK and NF-κB play an important role in an animal model of autoimmune hepatitis (AIH) induced by autoantigens.展开更多
Progranulin is closely related to neuronal survival in a neuroinflammatory mouse model and attenuates inflammatory reactions. Atsttrin is an engineered protein composed of three progranulin fragments and has been show...Progranulin is closely related to neuronal survival in a neuroinflammatory mouse model and attenuates inflammatory reactions. Atsttrin is an engineered protein composed of three progranulin fragments and has been shown to have an effect similar to that of progranulin. Atsttrin has anti-inflammatory actions in multiple arthritis mouse models, and it protects against further arthritis development. However, whether Atsttrin has a role in neuroinflammation remains to be elucidated. In this study, we produced a neuroinflammatory mouse model by intracerebroventricular injection of 1 μL lipopolysaccharide(10 μg/μL). Atsttrin(2.5 mg/kg) was administered via intraperitoneal injection every 3 days over a period of 7 days before intracerebroventricular injection of 1 μL lipopolysaccharide(10 μg/μL). In addition, astrocyte cultures were treated with 0, 100 or 300 ng/mL lipopolysaccharide, with 200 ng/mL Atsttrin simultaneously. Immunohistochemistry, enzyme-linked immunosorbent assay and real-time reverse transcription-polymerase chain reaction were performed to examine the protein and mRNA levels of inflammatory mediators and to assess activation of the nuclear factor kappa B signaling pathway. Progranulin expression in the brain of wild-type mice and in astrocyte cultures was increased after lipopolysaccharide administration. The protein and mRNA expression levels of tumor necrosis factor-α, interleukin-1β and inducible nitric oxide synthase were increased in the brain of progranulin knockout mice after lipopolysaccharide administration. Atsttrin treatment reduced the lipopolysaccharide-induced increase in the protein and mRNA levels of tumor necrosis factor-α, interleukin-1β, matrix metalloproteinase-3 and inducible nitric oxide synthase in the brain of progranulin knockout mice. Atsttrin also reduced the expression of cyclooxygenase-2, inducible nitric oxide synthase and matrix metalloproteinase 3 mRNA in lipopolysaccharide-treated astrocytes in vitro, and decreased the concentration of tumor necrosis factor α and interleukin-1β in the supernatant. Furthermore, Atsttrin significantly reduced the levels of phospho-nuclear factor kappa B inhibitor α in the brain of lipopolysaccharide-treated progranulin knockout mice and astrocytes, and it decreased the expression of nuclear factor kappa B2 in astrocytes. Collectively, our findings show that the anti-neuroinflammatory effect of Atsttrin involves inhibiton of the nuclear factor kappa B signaling pathway, and they suggest that Atsttrin may have clinical potential in neuroinflammatory therapy.展开更多
AIM:To investigate genetic diversity of Helicobacter pylori (H.pylori) cell division-related gene A (cdrA) and its effect on the host response.METHODS:Inactivation of H.pylori cdrA,which is involved in cell division a...AIM:To investigate genetic diversity of Helicobacter pylori (H.pylori) cell division-related gene A (cdrA) and its effect on the host response.METHODS:Inactivation of H.pylori cdrA,which is involved in cell division and morphological elongation,has a role in chronic persistent infections.Genetic property of H.pylori cdrA was evaluated using polymerase chain reaction and sequencing in 128 (77 American and 51 Japanese) clinical isolates obtained from 48 and 51 patients,respectively.Enzyme-linked immunosorbent assay was performed to measure interleukin-8 (IL-8) secretion with gastric biopsy specimens obtained from American patients colonized with cdrA-positive or-negative strains and AGS cells cocultured with wild-type HPK5 (cdrA-positive) or its derivative HPKT510 (cdrA-disruptant).Furthermore,the cytotoxin-associated gene A (cagA) status (translocation and phosphorylation) and kinetics of transcription factors [nuclear factor-kappa B (NF-κB) and inhibition kappa B] were investigated in AGS cells co-cultured with HPK5,HPKT510 and its derivative HPK5CA (cagA disruptant) by western blotting analysis with immunoprecipitation.RESULTS:Genetic diversity of the H.pylori cdrA gene demonstrated that the cdrA status segregated into two categories including four allele types,cdrA-positive (allele types;Ⅰand Ⅱ) and cdrA-negative (allele types;Ⅲ and Ⅳ) categories,respectively.Almost all Japanese isolates were cdrA-positive (Ⅰ:7.8% and Ⅱ:90.2%),whereas 16.9% of American isolates were cdrA-positive (Ⅱ) and 83.1% were cdrA-negative (Ⅲ:37.7% and Ⅳ:45.5%),indicating extended diversity of cdrA in individual American isolates.Comparison of each isolate from different regions (antrum and corpus) in the stomach of 29 Americans revealed that cdrA status was identical in both isolates from different regions in 17 cases.However,12 cases had a different cdrA allele and 6 of them exhibited a different cdrA category between two regions in the stomach.Furthermore,in 5 of the 6 cases possessing a different cdrA category,cdrA-negative isolate existed in the corpus,suggesting that cdrA-negative strain is more adaptable to colonization in the corpus.IL-8 secretions from AGS revealed that IL-8 levels induced by a cdrA-disrupted HPKT510 was significantly lower (P < 0.01) compared to wildtype HPK5:corresponding to 50%-60% of those of wild-type HPK5.These data coincided with in vivo data that an average value of IL-8 in biopsy specimens from cdrA-positive and cdrA-negative groups was 215.6 and 135.9 pg/mL,respectively.Western blotting analysis documented that HPKT510 had no effect on CagA translocation and phosphorylation,however,nuclear accumulation of NF-κB was lower by HPKT510 compared to HPK5.CONCLUSION:Colonization by a cdrA-negative or cdrA-dysfunctional strain resulted in decreased IL-8 production and repression of NF-κB,and hence,attenuate the host immunity leading to persistent infection.展开更多
BACKGROUND: L-3-n-butylphthalide (L-NBP) can inhibit phosphorylation of tau protein and reduce the neurotoxicity of beta-amyloid peptide 1-42 (Aβ1-42). OBJECTIVE: To observe the neuroprotective effects of L-NBP...BACKGROUND: L-3-n-butylphthalide (L-NBP) can inhibit phosphorylation of tau protein and reduce the neurotoxicity of beta-amyloid peptide 1-42 (Aβ1-42). OBJECTIVE: To observe the neuroprotective effects of L-NBP on caspase-3 and nuclear factor kappa-B (NF- K B) expression in a rat model of Alzheimer's disease. DESIGN, TIME AND SETTING: A cell experiment was performed at the Central Laboratory of Provincial Hospital affiliated to Shandong University between January 2008 and August 2008. MATERIALS: L-NBP (purity 〉 98%) was provided by Shijiazhuang Pharma Group NBP Pharmaceutical Company Limited. Aβ1-42, 3-[4,5-dimethylthiazolo-2]-2,5 iphenyltetrazolium bromide (MTT), and rabbit anti-Caspase-3 polyclonal antibody were provided by Cell Signaling, USA; goat anti-choactase and rabbit anti-NF- kB antibodies were provided by Santa Cruz, USA. METHODS: Primary cultures were generated from rat basal forebrain and hippocampal neurons at 17 or 19 days of gestation. The cells were assigned into five groups: the control group, the Aβ1-42 group (2 μmol/L), the Aβ1-42 + 0.1 μmol/L L-NBP group, the Aβ1-42 + 1 μ mol/L L-NBP group, and the Aβ1-42 + 10μmol/L L-NBP group. The neurons were treated with Aβ1-42 (2 μmol/L) alone or in combination with L-NBP (0.1, 1, 10 μmol/L) for 48 hours. Cells in the control group were incubated in PBS. MAIN OUTCOME MEASURES: Morphologic changes were evaluated using inverted microscopy, viability using the M-I-I- method, and the changes in caspase-3 and NF- k B expression using Western blot. RESULTS: Induction with Aβ1-42 for 48 hours caused cell death and soma atrophy, and increased caspase-3 and NF- K B expression (P 〈 0.05). L-NBP blocked these changes in cell morphology, decreased caspase-3 and NF- k B expression (P 〈 0.05), and improved cell viability, especially at the high dose (P 〈 0.05). CONCLUSION: AI3^-42 is toxic to basal forebrain and hippocampal primary neurons; L-NBP protects against this toxicity and inhibits the induction of caspase-3 and NF- K B expression.展开更多
This study sought to elucidate the changes of nuclear factor kappa B (NF-KB) expression and locomotor function of hind limb after subdural injection of BMS-345541 was applied in rats with acute spinal cord injury. T...This study sought to elucidate the changes of nuclear factor kappa B (NF-KB) expression and locomotor function of hind limb after subdural injection of BMS-345541 was applied in rats with acute spinal cord injury. The results indicated that BMS-345541 treatment reduced the expression of NF-kB at 24 hours after injury, compared with normal saline-treated rats. This treatment also led to a significant improvement in locomotor functional recovery at 14 days after injury. Overall, the findings demonstrated that BMS-345541 significantly ameliorated spinal cord injury-induced hind limb dysfunction by inhibiting the expression of NF-kB after spinal cord injury.展开更多
Previous studies have confirmed that the anti-virus effects of Shuanghuanglian injection may be associated with nuclear factor-kappa B activity. This study observed nuclear factor-kappa B expression in mice with viral...Previous studies have confirmed that the anti-virus effects of Shuanghuanglian injection may be associated with nuclear factor-kappa B activity. This study observed nuclear factor-kappa B expression in mice with viral encephalitis, and showed significant decreases in nuclear factor-kappa B protein and mRNA levels following Shuanghuanglian injection. The inhibitory effect was more significant with prolonged intervention duration and increased treatment dose. These findings verify that Shuanghuanglian injection plays a therapeutic role in viral encephalitis by reducing expression of nuclear factor-kappa B in a time- and dose-dependent manner.展开更多
A mouse model of viral encephalitis was induced by intracranial injection of a Coxsackie virus B3 suspension. Quantitative real-time reverse transcription-PCR and western blot assay were applied to detect mRNA and pro...A mouse model of viral encephalitis was induced by intracranial injection of a Coxsackie virus B3 suspension. Quantitative real-time reverse transcription-PCR and western blot assay were applied to detect mRNA and protein expression of intelectin-2 and nuclear factor-kappa B in the viral encephalitis and control groups. Nuclear factor-kappa B and intelectin-2 mRNA and protein expression were significantly increased in mice with viral encephalitis. After intraperitoneal injection of Shuanghuanglian at a dose of 1.5 mg/kg for 5 successive days, intelectin-2 and nuclear factor-kappa B protein and mRNA expression were significantly decreased. To elucidate the relationship between intelectin-2 and nuclear factor-kappa B, mice with viral encephalitis were administered an intracerebral injection of 107 pfu recombinant lentivirus expressing intelectin shRNA. Both protein and mRNA levels of intelectin and nuclear factor-kappa B in brain tissue of mice were significantly decreased. Experimental findings suggest that Shuanghuanglian injection may downregulate nuclear factor-kappa B production via suppression of intelectin production, thus inhibiting inflammation associated with viral encephalitis.展开更多
The relation between the expression and activity of MMP-9 in C-reactive protein (CRP)-induced human THP-1 mononuclear cells and the activation of nuclear factor kappa-B (NF-κB) was studied to investigate the poss...The relation between the expression and activity of MMP-9 in C-reactive protein (CRP)-induced human THP-1 mononuclear cells and the activation of nuclear factor kappa-B (NF-κB) was studied to investigate the possible role of CRP in plaque destabilization. Human THP-1 cells were incubated in the presence of CRP at 0 (control group), 25, 50 and 100 μg/mL (CRP groups) for 24 h. In PDTC (a specific NF-κB inhibitor) group, the cells were pre-treated with PDTC at 10 μmol/L and then with 100 μg/mL CRP. The conditioned media (CM) and human THP-1 cells in different groups were harvested. MMP-9 expression in CM and human THP-1 cells was measured by ELISA and Western blotting. MMP-9 activity was assessed by fluorogenic substrates. The expression of NF-κB inhibitor α (IκB-α) and NF-κB p65 was detected by Western blotting and ELISA respectively. The results showed that CRP increased the expression and activity of MMP-9 in a dose-dependent manner in the human THP-1 cells. Western blotting revealed that IiB-α expression was decreased in the cells with the concentrations of CRP and ELISA demonstrated that NF-κB p65 expression in the CRP-induced cells was increased. After pre-treatment of the cells with PDTC at 10 μmol/L, the decrease in IκB-α expression and the increase in NF-κB p65 expression in the CRP-induced cells were inhibited, and the expression and activity of MMP-9 were lowered too. It is concluded that increased expression and activity of MMP-9 in CRP-induced human THP-1 cells may be associated with activation of NF-κB. Down-regulation of the expression and activity of MMP-9 may be a new treatment alternative for plaque stabilization by inhibiting the NF-κB activation.展开更多
Objective: To explore the underlying molecular mechanisms of cellular response to the challenge by 1-methyl-4-phenylpyridinium (MPP+)-induced apoptosis of PC12 cells, an in vitro cell model for Parkinson’s disease, a...Objective: To explore the underlying molecular mechanisms of cellular response to the challenge by 1-methyl-4-phenylpyridinium (MPP+)-induced apoptosis of PC12 cells, an in vitro cell model for Parkinson’s disease, and the effect of NF-κB activation on the protection of Parkinson’s disease by Isoflavone (I). Methods: PC12 cells were used to establish the cell model of Parkinson’s disease, and are divided into five groups: control group;MPP+ group;I (Isoflavone) + MPP+ group;I group;SN-50 + MPP+ group. The content of NF-κB in PC12 cells was determined by immunocytochemistry;The viability of PC12 cells after treated with cell-permeable NF-κB inhibitor SN-50 and cell viability were measured by MTT assay;the expression levels of NF-κB p65 in cytoplasm and nuclear fractions were evaluated by western blot analysis;the mRNA expression of NF-κB p65 was analyzed by in situ hybridization (ISH). Results: Compared with the control group, the protein of NF-κB p65 both in cytoplasm and in nuclei was significantly higher than in I + MPP+ and MPP+ groups;similarly, the mRNA expression level of NF-κB p65 gene was also significantly higher;moreover, the protein expression of NF-κB p65 was much lower in I group (P + group, the protein of NF-κB p65 was significantly lower in I + MPP+ group, the mRNA expression level of NF-κB p65 gene was also significantly lower, and the protein expression level of NF-κB p65 was much lower in I + MPP+ group (P + group (P > 0.05). Conclusion: NF-κB activation is essential to MPP+-induced apoptosis in PC12 cells;but Isoflavone can inhibit the cell damage to some extent to execute its protective function, which may be involved in nigral neurodegeneration in patients with Parkinson’s disease.展开更多
In order to investigate the effect of nuclear factor kappa B (NF κB) on vascular endothelial growth factor (VEGF) mRNA expression of human pulmonary artery smooth muscle cells (HPASMCs) in hypoxia, the cultured HPA...In order to investigate the effect of nuclear factor kappa B (NF κB) on vascular endothelial growth factor (VEGF) mRNA expression of human pulmonary artery smooth muscle cells (HPASMCs) in hypoxia, the cultured HPASMCs in vitro were stimulated with pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF κB. The NF κB p65 nuclei positive expression was detected by immunocytochemical technique. The IκBα protein expression was measured by Western blot. RT PCR was used to detect the VEGF mRNA expression of HPASMCs. The results showed that no significant change was observed in the NF κB p65 nuclei positive expression of cultured HPASMCs during 6 h-24 h in normoxia, but the levels of NF κB p65 nuclei positive expression of cultured HPASMCs were significantly increased in hypoxia groups as compared with those in all normoxia groups ( P <0.05). The IκBα protein expression of cultured HPASMCs showed no significant change during 6 h-24 h in normoxia, but significantly decreased in hypoxia as comapred with that in normoxia groups ( P <0.05). PDTC (1 to 100 μmol/L) could inhibit the VEGF mRNA expression of HPASMCs in a concentration dependent manner in hypoxia. In conclusion, NF κB can be partly translocation activated from cytoplasm into nuclei in the cultured HPASMCs under hypoxia. The inhibition of NF κB activation can decrease the VEGF mRNA expression. It is suggested that the activation of NF κB is involved in the VEGF mRNA expression of HPASMCs under hypoxia.展开更多
The effects of five chito-oligomers, from dimer to hexamer (chitobiose, chitotriose, chitotetraose, chitopentaose, chitohexaose) separated from chitosan oligosaccharides, on nuclear factor -kappaB (NF-rd3) signali...The effects of five chito-oligomers, from dimer to hexamer (chitobiose, chitotriose, chitotetraose, chitopentaose, chitohexaose) separated from chitosan oligosaccharides, on nuclear factor -kappaB (NF-rd3) signaling pathway were investigated by using luciferase assay and laser scanning microscopy. The expression of NF-rd3 downstream genes (cyclin DI, TNFa and IL-6) were tested by real time PCR. We found that all five chitosan oligosaccharides increased NF-KB-dependent luciferase gene expression and NF-KB downstream genes transcription, and the most significant were chitotetraose and chitohexaose. In addition, laser scanning microscopy experiments showed that chitotetraose and chitohexaose also activated the p65 subunite of NF-kB translocating from cytoplasm to nucleus, which suggested that they were the most potent activators of NF-kB signaling pathway.展开更多
基金supported by grants from the Project of Elitist Peak in Six Fields(No.2006-B-063)the Project of Medical Sciences(H200727),the Bureau of Health,Jiangsu Province,China
文摘BACKGROUND: The active form of nuclear factor-kappa B (NF-kappa B) is involved in the initiation, generation, and development of hepatocellular carcinoma (HCC), and is up-regulated in inflammation-associated malignancies. We investigated the dynamic expression of NF-kappa B and its influences on the occurrence of HCC through antiangiogenic (thalidomide) intervention in NF-kappa B activation. METHODS : Hepatoma models were induced with 2-fluorenylacetamide (2-FAA, 0.05%) in male Sprague-Dawley rats, and thalidomide (100 mg/kg body weight) was administered intragastrically to intervene in NF-kappa B activation. The pathological changes in the liver of sacrificed rats were assessed after hematoxylin and eosin staining. NF-kappa B mRNA was amplified by RT-nested PCR. The alterations of NF-kappa B and vascular endothelial growth factor (VEGF) expression were analyzed by enzyme-linked immunosorbent assay, immunohistochemistry, and Western blotting. RESULTS: Rat hepatocytes showed denatured, precancerous, and cancerous stages in hepatocarcinogenesis, with an increasing tendency of hepatic NF-kappa B, NF-kappa B mRNA, and VEGF expression, and their values in the HCC group were higher than those in controls (P<0.001). In the thalidomide-treated group, the morphologic changes generated only punctiform denaturation and necrosis at the early or middle stages, and nodular hyperplasia or a little atypical hyperplasia at the final stages, with the expression of NF-kappa B (chi(2)=9.93, P<0.001) and VEGF (chi(2)=8.024, P<0.001) lower than that in the 2-FAA group. CONCLUSION: NF-kappa B is overexpressed in hepatocarcinogenesis and antiangiogenic treatment down-regulates the expression of NF-kappa B and VEGF, and delays the occurrence of HCC. (Hepatobiliary Pancreat Dis Int 2010; 9: 169-174)
文摘BACKGROUND: Urinary trypsin inhibitor (UTI) inhibits the inflammatory response and protects against ischemia-reperfusion (I/R) injury. The inflammatory response is mediated by nuclear factor-kappa B (NF-kappa B) and its related target genes and products such as vascular endothelial cell adhesion molecule and CXC chemokines. We aimed to assess the roles of those mediators in a UTI-treated mouse model of hepatic I/R injury. METHODS: Treatment group 1 (UTI given 5 minutes prior to liver ischemia), treatment group 2 (UTI given 5 minutes after the anhepatic phase) and a control group were investigated. Blood and liver samples were obtained and compared at 1, 3, 6 and 24 hours after reperfusion. RESULTS: Attenuation of pathological hepatocellular damage was greater in the treatment groups than in the control group (P < 0.05). Compared with the control group, the UTI treatment groups showed significantly lower serum alanine aminotransferase and aspartate aminotransferase levels, decreased myeloperoxidase activity, and reduced NF-kappa B activation. Also downregulated was the expression of tumor necrosis factor-alpha, cytokine-induced neutrophil chemoattractant, and macrophage inflammatory protein-2 at the mRNA level. P-selectin protein and intercellular adhesion molecule-1 protein expression were also downregulated. In addition, the treatment group I showed a better protective effect against I/R injury than the treatment group 2. CONCLUSIONS: UTI reduces NF-kappa B activation and downregulates the expression of its related mediators, followed by the inhibition of neutrophil aggregation and infiltration in hepatic I/R injury. The protective role of UTI is more effective in prevention than in treatment.
基金Supported by Scientific Research Foundation of the Chinese PLA Key Medical Programs During the 10th Five-Year Plan Period, No. 01Z011
文摘AIM: Nuclear factor kappa B (NF-κB) regulates a large number of genes involved in the inflammatory response to critical illnesses, but it is not known if and how NF-κB is activated and intercellular adhesion molecule-1 (ICAM-1)expressed in the gut following traumatic brain injury (TBI).The aim of current study was to investigate the temporal pattern of intestinal NF-κB activation and ICAM-1expression following TBI.METHODS: Male Wistar rats were randomly divided into six groups (6 rats in each group) including controls with sham operation and TBI groups at hours 3, 12, 24, and 72, and on d 7. Parietal brain contusion was adopted using weight-dropping method. All rats were decapitated at corresponding time point and mid-jejunum samples were taken. NF-κB binding activity in jejunal tissue was measured using EMSA. Immunohistochemistry was used for detection of ICAM-1 expression in jejunal samples.RESULTS: There was a very low NF-κB binding activity and little ICAM-1 expression in the gut of control rats after sham surgery. NF-κB binding activity in jejunum significantly increased by 160% at 3 h following TBI (P<0.05 vs control), peaked at 72 h (500% increase)and remained elevated on d 7 post-injury by 390% increase. Compared to controls, ICAM-1 was significantly up-regulated on the endothelia of microvessels in villous interstitium and lamina propria by 24 h following TBI and maximally expressed at 72 h post-injury (P<0.001). The endothelial ICAM-1 immunoreactivity in jejunal mucosa still remained strong on d 7 post-injury. The peak of NF-κB activation and endothelial ICAM-1 expression coincided in time with the period during which secondary mucosal injury of the gut was also at their culmination following TBI.CONCLUSION: TBI could induce an immediate and persistent up-regulation of NF-κB activity and subsequent up-regulation of ICAM-1 expression in the intestine.Inflammatory response mediated by increased NF-κB activation and ICAM-1 expression may play an important role in the pathogenesis of acute gut mucosal injury following TBI.
基金Supported by The National Natural Science Foundation of ChinaNO.81170374 and NO.81470842 to Hua J
文摘AIM: To investigate the effect of different dietary fatty acids on hepatic inflammasome activation.METHODS: Wild-type C57BL/6 mice were fed either a high-fat diet or polyunsaturated fatty acid(PUFA)-enriched diet. Primary hepatocytes were treated with either saturated fatty acids(SFAs) or PUFAs as well as combined with lipopolysaccharide(LPS). The expression of NOD-like receptor protein 3(NLRP3) inflammasome, peroxisome proliferator-activated receptor-γ and nuclear factor-kappa B(NF-κB) was determined by real-time PCR and Western blot. The activity of Caspase-1 and interleukine-1β production were measured.RESULTS: high-fat diet-induced hepatic steatosis was sufficient to induce and activate hepatic NLRP3 inflammasome. SFA palmitic acid(PA) directly activated NLRP3 inflammasome and increased sensitization to LPS-induced inflammasome activation in hepatocytes. In contrast, PUFA docosahexaenoic acid(Dh A) had thepotential to inhibit NLRP3 inflammasome expression in hepatocytes and partly abolished LPS-induced NLRP3 inflammasome activation. Furthermore, a highfat diet increased but PUFA-enriched diet decreased sensitization to LPS-induced hepatic NLRP3 inflammasome activation in vivo. Moreover, PA increased but Dh A decreased phosphorylated NF-κB p65 protein expression in hepatocytes.CONCLUSION:Hepatic NLRP 3 inflammasome activation played an important role in the development of non-alcoholic fatty liver disease. Dietary SFAs and PUFAs oppositely regulated the activity of NLRP3 inflammasome through direct activation or inhibition of NF-κB.
基金supported by grants from the Project of Elitist Peak in Six Fields(No.2006-B-063)the Projectof Medical Sciences(H200727),the Bureau of Health,Jiangsu Province,China
文摘BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. We analyzed the expression of miclear-transcription factor-kappa B (NF-kappa B) during hepatocarcinogenesis in order to evaluate its dynamic expression and its clinical value in the development and diagnosis of HCC. METHODS: Hepatoma models were induced by oral administration of 2-acetamidoflurene (2-FAA) to male Sprague-Dawley rats. Morphological changes were observed after hematoxylin and eosin staining. The cellular distribution of NF-kappa B expression during different stages of cancer development was investigated by immunohistochemistry, and the level of NF-kappa B expression in liver tissues was quantitatively analyzed by ELISA. The gene fragments of hepatic NF-kappa B were amplified by nested-polymerase chain reaction assay. RESULTS: Hepatocytes showed vacuole-like degeneration during the early stages, then had a hyperplastic nodal appearance during the middle stages, and finally progressed to tubercles of cancerous nests with high differentiation. The NF-kappa B-positive material was buff-colored, fine particles localized in the nucleus, and the incidence of NF-kappa B-positive cells was 81.8% in degeneration, 83.3% in precancerous lesions, and 100% in cancerous tissues. All of these values were higher than those in controls (P<0.01). Hepatic NF-kappa B expression and hepatic NF-kappa B-mRNA were also higher during the course of HCC development (P<0.01). CONCLUSION: The NF-kappa B signal transduction pathway is activated during the early stages of HCC development, and its abnormal expression may be associated with the occurrence of HCC.
基金Supported by grants from National Natural Science Foundation of China, No. 30471614 (to DK Qiu) and No.30571730 (to X Ma)Shanghai Leading Academic Discipline Project, No.Y0205 (to X Ma)
文摘AIM: To investigate the role of p38 mitogen-activated protein kinase (p38MAPK) in murine experimental autoimmune hepatitis (EAH). METHODS: To induce EAH, the syngeneic S-100 antigen emulsified in complete Freud's adjuvant was injected intraperitoneally into adult male C57Bl/6 mice. Liver injury was assessed by serum ALT and liver histology. The expression and activity of p38 MAPK were measured by Western blot and kinase activity assays. In addition, DNA binding activities of nuclear factor kappa B (NF-κB) were analyzed by electrophoretic mobility shift assay. The effects of SB203580, a specifi c p38 MAPK inhibitor, on liver injuries and expression of proin? ammatory cytokines (interferon-γ, IL-12, IL-1β and TNF-α) were observed. RESULTS: The activity of p38 MAPK and NF-κB was increased and reached its peak 14 or 21 d after the fi rst syngeneic S-100 administration. Inhibition of p38 MAPK activation by SB203580 decreased the activation of NF-κB and the expression of proin? ammatory cytokines. Moreover, hepatic injuries were improved significantly after SB203580 administration. CONCLUSION: p38 MAPK and NF-κB play an important role in an animal model of autoimmune hepatitis (AIH) induced by autoantigens.
基金supported by the National Natural Science Foundation of China,No.81572191(to LC)and 81601067(to HZ)
文摘Progranulin is closely related to neuronal survival in a neuroinflammatory mouse model and attenuates inflammatory reactions. Atsttrin is an engineered protein composed of three progranulin fragments and has been shown to have an effect similar to that of progranulin. Atsttrin has anti-inflammatory actions in multiple arthritis mouse models, and it protects against further arthritis development. However, whether Atsttrin has a role in neuroinflammation remains to be elucidated. In this study, we produced a neuroinflammatory mouse model by intracerebroventricular injection of 1 μL lipopolysaccharide(10 μg/μL). Atsttrin(2.5 mg/kg) was administered via intraperitoneal injection every 3 days over a period of 7 days before intracerebroventricular injection of 1 μL lipopolysaccharide(10 μg/μL). In addition, astrocyte cultures were treated with 0, 100 or 300 ng/mL lipopolysaccharide, with 200 ng/mL Atsttrin simultaneously. Immunohistochemistry, enzyme-linked immunosorbent assay and real-time reverse transcription-polymerase chain reaction were performed to examine the protein and mRNA levels of inflammatory mediators and to assess activation of the nuclear factor kappa B signaling pathway. Progranulin expression in the brain of wild-type mice and in astrocyte cultures was increased after lipopolysaccharide administration. The protein and mRNA expression levels of tumor necrosis factor-α, interleukin-1β and inducible nitric oxide synthase were increased in the brain of progranulin knockout mice after lipopolysaccharide administration. Atsttrin treatment reduced the lipopolysaccharide-induced increase in the protein and mRNA levels of tumor necrosis factor-α, interleukin-1β, matrix metalloproteinase-3 and inducible nitric oxide synthase in the brain of progranulin knockout mice. Atsttrin also reduced the expression of cyclooxygenase-2, inducible nitric oxide synthase and matrix metalloproteinase 3 mRNA in lipopolysaccharide-treated astrocytes in vitro, and decreased the concentration of tumor necrosis factor α and interleukin-1β in the supernatant. Furthermore, Atsttrin significantly reduced the levels of phospho-nuclear factor kappa B inhibitor α in the brain of lipopolysaccharide-treated progranulin knockout mice and astrocytes, and it decreased the expression of nuclear factor kappa B2 in astrocytes. Collectively, our findings show that the anti-neuroinflammatory effect of Atsttrin involves inhibiton of the nuclear factor kappa B signaling pathway, and they suggest that Atsttrin may have clinical potential in neuroinflammatory therapy.
基金Supported by The Project Research Fund from Kochi University,to Takeuchi Ha Grant-in-Aid for Scientific Research from the Ministry of Education,Science and Culture of Japan,No. 21590631 and 21590629,in part
文摘AIM:To investigate genetic diversity of Helicobacter pylori (H.pylori) cell division-related gene A (cdrA) and its effect on the host response.METHODS:Inactivation of H.pylori cdrA,which is involved in cell division and morphological elongation,has a role in chronic persistent infections.Genetic property of H.pylori cdrA was evaluated using polymerase chain reaction and sequencing in 128 (77 American and 51 Japanese) clinical isolates obtained from 48 and 51 patients,respectively.Enzyme-linked immunosorbent assay was performed to measure interleukin-8 (IL-8) secretion with gastric biopsy specimens obtained from American patients colonized with cdrA-positive or-negative strains and AGS cells cocultured with wild-type HPK5 (cdrA-positive) or its derivative HPKT510 (cdrA-disruptant).Furthermore,the cytotoxin-associated gene A (cagA) status (translocation and phosphorylation) and kinetics of transcription factors [nuclear factor-kappa B (NF-κB) and inhibition kappa B] were investigated in AGS cells co-cultured with HPK5,HPKT510 and its derivative HPK5CA (cagA disruptant) by western blotting analysis with immunoprecipitation.RESULTS:Genetic diversity of the H.pylori cdrA gene demonstrated that the cdrA status segregated into two categories including four allele types,cdrA-positive (allele types;Ⅰand Ⅱ) and cdrA-negative (allele types;Ⅲ and Ⅳ) categories,respectively.Almost all Japanese isolates were cdrA-positive (Ⅰ:7.8% and Ⅱ:90.2%),whereas 16.9% of American isolates were cdrA-positive (Ⅱ) and 83.1% were cdrA-negative (Ⅲ:37.7% and Ⅳ:45.5%),indicating extended diversity of cdrA in individual American isolates.Comparison of each isolate from different regions (antrum and corpus) in the stomach of 29 Americans revealed that cdrA status was identical in both isolates from different regions in 17 cases.However,12 cases had a different cdrA allele and 6 of them exhibited a different cdrA category between two regions in the stomach.Furthermore,in 5 of the 6 cases possessing a different cdrA category,cdrA-negative isolate existed in the corpus,suggesting that cdrA-negative strain is more adaptable to colonization in the corpus.IL-8 secretions from AGS revealed that IL-8 levels induced by a cdrA-disrupted HPKT510 was significantly lower (P < 0.01) compared to wildtype HPK5:corresponding to 50%-60% of those of wild-type HPK5.These data coincided with in vivo data that an average value of IL-8 in biopsy specimens from cdrA-positive and cdrA-negative groups was 215.6 and 135.9 pg/mL,respectively.Western blotting analysis documented that HPKT510 had no effect on CagA translocation and phosphorylation,however,nuclear accumulation of NF-κB was lower by HPKT510 compared to HPK5.CONCLUSION:Colonization by a cdrA-negative or cdrA-dysfunctional strain resulted in decreased IL-8 production and repression of NF-κB,and hence,attenuate the host immunity leading to persistent infection.
基金Supported by:the Medicine and Health Scientific Research Projects of Shandong Province,No. 2007HZ065
文摘BACKGROUND: L-3-n-butylphthalide (L-NBP) can inhibit phosphorylation of tau protein and reduce the neurotoxicity of beta-amyloid peptide 1-42 (Aβ1-42). OBJECTIVE: To observe the neuroprotective effects of L-NBP on caspase-3 and nuclear factor kappa-B (NF- K B) expression in a rat model of Alzheimer's disease. DESIGN, TIME AND SETTING: A cell experiment was performed at the Central Laboratory of Provincial Hospital affiliated to Shandong University between January 2008 and August 2008. MATERIALS: L-NBP (purity 〉 98%) was provided by Shijiazhuang Pharma Group NBP Pharmaceutical Company Limited. Aβ1-42, 3-[4,5-dimethylthiazolo-2]-2,5 iphenyltetrazolium bromide (MTT), and rabbit anti-Caspase-3 polyclonal antibody were provided by Cell Signaling, USA; goat anti-choactase and rabbit anti-NF- kB antibodies were provided by Santa Cruz, USA. METHODS: Primary cultures were generated from rat basal forebrain and hippocampal neurons at 17 or 19 days of gestation. The cells were assigned into five groups: the control group, the Aβ1-42 group (2 μmol/L), the Aβ1-42 + 0.1 μmol/L L-NBP group, the Aβ1-42 + 1 μ mol/L L-NBP group, and the Aβ1-42 + 10μmol/L L-NBP group. The neurons were treated with Aβ1-42 (2 μmol/L) alone or in combination with L-NBP (0.1, 1, 10 μmol/L) for 48 hours. Cells in the control group were incubated in PBS. MAIN OUTCOME MEASURES: Morphologic changes were evaluated using inverted microscopy, viability using the M-I-I- method, and the changes in caspase-3 and NF- k B expression using Western blot. RESULTS: Induction with Aβ1-42 for 48 hours caused cell death and soma atrophy, and increased caspase-3 and NF- K B expression (P 〈 0.05). L-NBP blocked these changes in cell morphology, decreased caspase-3 and NF- k B expression (P 〈 0.05), and improved cell viability, especially at the high dose (P 〈 0.05). CONCLUSION: AI3^-42 is toxic to basal forebrain and hippocampal primary neurons; L-NBP protects against this toxicity and inhibits the induction of caspase-3 and NF- K B expression.
文摘This study sought to elucidate the changes of nuclear factor kappa B (NF-KB) expression and locomotor function of hind limb after subdural injection of BMS-345541 was applied in rats with acute spinal cord injury. The results indicated that BMS-345541 treatment reduced the expression of NF-kB at 24 hours after injury, compared with normal saline-treated rats. This treatment also led to a significant improvement in locomotor functional recovery at 14 days after injury. Overall, the findings demonstrated that BMS-345541 significantly ameliorated spinal cord injury-induced hind limb dysfunction by inhibiting the expression of NF-kB after spinal cord injury.
基金the Health Research Fund from Health Department of Shaanxi Province,China,No. 04015
文摘Previous studies have confirmed that the anti-virus effects of Shuanghuanglian injection may be associated with nuclear factor-kappa B activity. This study observed nuclear factor-kappa B expression in mice with viral encephalitis, and showed significant decreases in nuclear factor-kappa B protein and mRNA levels following Shuanghuanglian injection. The inhibitory effect was more significant with prolonged intervention duration and increased treatment dose. These findings verify that Shuanghuanglian injection plays a therapeutic role in viral encephalitis by reducing expression of nuclear factor-kappa B in a time- and dose-dependent manner.
基金funded by the Health Research Fund from the Health Department of Shanxi Province, China, No.04015
文摘A mouse model of viral encephalitis was induced by intracranial injection of a Coxsackie virus B3 suspension. Quantitative real-time reverse transcription-PCR and western blot assay were applied to detect mRNA and protein expression of intelectin-2 and nuclear factor-kappa B in the viral encephalitis and control groups. Nuclear factor-kappa B and intelectin-2 mRNA and protein expression were significantly increased in mice with viral encephalitis. After intraperitoneal injection of Shuanghuanglian at a dose of 1.5 mg/kg for 5 successive days, intelectin-2 and nuclear factor-kappa B protein and mRNA expression were significantly decreased. To elucidate the relationship between intelectin-2 and nuclear factor-kappa B, mice with viral encephalitis were administered an intracerebral injection of 107 pfu recombinant lentivirus expressing intelectin shRNA. Both protein and mRNA levels of intelectin and nuclear factor-kappa B in brain tissue of mice were significantly decreased. Experimental findings suggest that Shuanghuanglian injection may downregulate nuclear factor-kappa B production via suppression of intelectin production, thus inhibiting inflammation associated with viral encephalitis.
文摘The relation between the expression and activity of MMP-9 in C-reactive protein (CRP)-induced human THP-1 mononuclear cells and the activation of nuclear factor kappa-B (NF-κB) was studied to investigate the possible role of CRP in plaque destabilization. Human THP-1 cells were incubated in the presence of CRP at 0 (control group), 25, 50 and 100 μg/mL (CRP groups) for 24 h. In PDTC (a specific NF-κB inhibitor) group, the cells were pre-treated with PDTC at 10 μmol/L and then with 100 μg/mL CRP. The conditioned media (CM) and human THP-1 cells in different groups were harvested. MMP-9 expression in CM and human THP-1 cells was measured by ELISA and Western blotting. MMP-9 activity was assessed by fluorogenic substrates. The expression of NF-κB inhibitor α (IκB-α) and NF-κB p65 was detected by Western blotting and ELISA respectively. The results showed that CRP increased the expression and activity of MMP-9 in a dose-dependent manner in the human THP-1 cells. Western blotting revealed that IiB-α expression was decreased in the cells with the concentrations of CRP and ELISA demonstrated that NF-κB p65 expression in the CRP-induced cells was increased. After pre-treatment of the cells with PDTC at 10 μmol/L, the decrease in IκB-α expression and the increase in NF-κB p65 expression in the CRP-induced cells were inhibited, and the expression and activity of MMP-9 were lowered too. It is concluded that increased expression and activity of MMP-9 in CRP-induced human THP-1 cells may be associated with activation of NF-κB. Down-regulation of the expression and activity of MMP-9 may be a new treatment alternative for plaque stabilization by inhibiting the NF-κB activation.
文摘Objective: To explore the underlying molecular mechanisms of cellular response to the challenge by 1-methyl-4-phenylpyridinium (MPP+)-induced apoptosis of PC12 cells, an in vitro cell model for Parkinson’s disease, and the effect of NF-κB activation on the protection of Parkinson’s disease by Isoflavone (I). Methods: PC12 cells were used to establish the cell model of Parkinson’s disease, and are divided into five groups: control group;MPP+ group;I (Isoflavone) + MPP+ group;I group;SN-50 + MPP+ group. The content of NF-κB in PC12 cells was determined by immunocytochemistry;The viability of PC12 cells after treated with cell-permeable NF-κB inhibitor SN-50 and cell viability were measured by MTT assay;the expression levels of NF-κB p65 in cytoplasm and nuclear fractions were evaluated by western blot analysis;the mRNA expression of NF-κB p65 was analyzed by in situ hybridization (ISH). Results: Compared with the control group, the protein of NF-κB p65 both in cytoplasm and in nuclei was significantly higher than in I + MPP+ and MPP+ groups;similarly, the mRNA expression level of NF-κB p65 gene was also significantly higher;moreover, the protein expression of NF-κB p65 was much lower in I group (P + group, the protein of NF-κB p65 was significantly lower in I + MPP+ group, the mRNA expression level of NF-κB p65 gene was also significantly lower, and the protein expression level of NF-κB p65 was much lower in I + MPP+ group (P + group (P > 0.05). Conclusion: NF-κB activation is essential to MPP+-induced apoptosis in PC12 cells;but Isoflavone can inhibit the cell damage to some extent to execute its protective function, which may be involved in nigral neurodegeneration in patients with Parkinson’s disease.
文摘In order to investigate the effect of nuclear factor kappa B (NF κB) on vascular endothelial growth factor (VEGF) mRNA expression of human pulmonary artery smooth muscle cells (HPASMCs) in hypoxia, the cultured HPASMCs in vitro were stimulated with pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF κB. The NF κB p65 nuclei positive expression was detected by immunocytochemical technique. The IκBα protein expression was measured by Western blot. RT PCR was used to detect the VEGF mRNA expression of HPASMCs. The results showed that no significant change was observed in the NF κB p65 nuclei positive expression of cultured HPASMCs during 6 h-24 h in normoxia, but the levels of NF κB p65 nuclei positive expression of cultured HPASMCs were significantly increased in hypoxia groups as compared with those in all normoxia groups ( P <0.05). The IκBα protein expression of cultured HPASMCs showed no significant change during 6 h-24 h in normoxia, but significantly decreased in hypoxia as comapred with that in normoxia groups ( P <0.05). PDTC (1 to 100 μmol/L) could inhibit the VEGF mRNA expression of HPASMCs in a concentration dependent manner in hypoxia. In conclusion, NF κB can be partly translocation activated from cytoplasm into nuclei in the cultured HPASMCs under hypoxia. The inhibition of NF κB activation can decrease the VEGF mRNA expression. It is suggested that the activation of NF κB is involved in the VEGF mRNA expression of HPASMCs under hypoxia.
基金Funded by the State High-Technology R&D Project of China (863 Program) ( 2007AA091603)
文摘The effects of five chito-oligomers, from dimer to hexamer (chitobiose, chitotriose, chitotetraose, chitopentaose, chitohexaose) separated from chitosan oligosaccharides, on nuclear factor -kappaB (NF-rd3) signaling pathway were investigated by using luciferase assay and laser scanning microscopy. The expression of NF-rd3 downstream genes (cyclin DI, TNFa and IL-6) were tested by real time PCR. We found that all five chitosan oligosaccharides increased NF-KB-dependent luciferase gene expression and NF-KB downstream genes transcription, and the most significant were chitotetraose and chitohexaose. In addition, laser scanning microscopy experiments showed that chitotetraose and chitohexaose also activated the p65 subunite of NF-kB translocating from cytoplasm to nucleus, which suggested that they were the most potent activators of NF-kB signaling pathway.