BACKGROUND: Receptors for tumor necrosis factor related apoptosis inducing ligand (TRAIL) include death receptor 4, death receptor 5, decoy receptor 1, and decoy receptor 2. Activation of death receptor 4 and 5 sel...BACKGROUND: Receptors for tumor necrosis factor related apoptosis inducing ligand (TRAIL) include death receptor 4, death receptor 5, decoy receptor 1, and decoy receptor 2. Activation of death receptor 4 and 5 selectively kills tumor cells. OBJECTIVE: To detect TRAIL receptor expression in glioblastoma by immunohistochemistry and RT-PCR, and to compare this expression to that in normal brain tissue. DESIGN: Observational analysis. SETTING: Department of Pathology, the First Affiliated Hospital of Zhengzhou University; Henan Tumor Pathology Key Laboratory. PARTICIPANTS: Twenty-five patients (17 males and 8 females) who received glioblastoma resection were selected from the Fifth Affiliated Hospital of Zhengzhou University, between September 2003 to June 2004. All glioblastoma samples were diagnosed pathologically. Twenty patients (12 males and 8 females) with craniocerebral injury who received normal brain tissue resection were selected in the same time period. There were no significant differences in sex and age between glioblastoma patients or between craniocerebral injury patients (P 〉 0.05). All patients and appropriate relatives provided informed consent, and this study was approved by the local research ethics committee. METHODS: Polyclonal antibody against TRAIL receptors and an immunohistochemical kit (batch number: 200502) were purchased from Boster Company, Wuhan. Immunohistochemistry: Expression of death receptor 4, death receptor 5, decoy receptor l, and decoy receptor 2 were observed in both glioblastoma and normal brain tissue. The experiment was performed according to the kit instructions, and positive staining was brown-yellow. Assessment: There were no positive signals (-); weakly positive signals, positive cells 〈 25% (+); weakly positive signals, positive cells 25%-50% (++); strongly positive signals, positive cells 50%-75% (+++); strongly positive signals, positive cells 〉 75% (++++). Evaluation: Expression levels of TRAIL receptors were estimated in both normal brain tissue and glioblastoma. Expression of decoy receptor 1 and decoy receptor 2 mRNA in glioblastoma were detected by reverse transcription polymerase chain reaction, and expression of decoy receptor in glioblastoma was estimated. MAIN OUTCOME MEASURES: Comparison of death receptor and decoy receptor protein expression between glioblastoma and normal brain tissue; decoy receptor mRNA expression in glioblastoma. RESULTS: Death receptor protein expression was strongly positive (+++) in glioblastoma, while it was weakly positive (+, ++) in normal brain tissue. Therefore, expression rate of death receptor protein in the glioblastoma was significantly higher than that in the normal brain tissue (.~ 2 = 18.48, 23.03, P 〈 0.01). Decoy receptor protein expression in the glioblastoma was significantly lower than that in the normal brain tissue ( x2 = 6.65, 18.76, P 〈 0.01). The level of decoy receptor mRNA expression in glioblastoma was significantly higher than those of protein expression ( x 2 = 9.82, 10.09, P〈 0.01). CONCLUSION: High expression of death receptor and low expression of decoy receptor are frequently observed in glioblastoma, suggesting that TRAIL receptor genes show an anti-tumor and expressive response during the initiation and development of the tumor. There are significant differences in decoy receptor expression between normal brain tissue and glioblastoma, suggesting that the restricted expression of decoy receptor in glioblastoma is regulated at the post-transcriptional level.展开更多
BACKGROUND: Previous studies have reported that statins are less toxic to the human body and have greater antitumor activity; however, few studies have addressed the antitumor effect of statins combined with tumor ne...BACKGROUND: Previous studies have reported that statins are less toxic to the human body and have greater antitumor activity; however, few studies have addressed the antitumor effect of statins combined with tumor necrosis factor-related apoptosis inducing ligand (TRAIL). OBJECTIVE: To explore the effect of TRAIL combined with mevastatin on the proliferation and apoptotic cell death of a human glioma cell line SWO-38, and to study its mechanism of action. DESIGN, TIME AND SETTING: An in vitro control experiment was performed at the Central Laboratory of the Third Hospital Affiliated to Sun Yat-sen University, between January and April 2009. MATERIALS: The human SWO-38 cell line was provided by Cell Research, Department of Animal Experimental Center of Sun Yat-sen University; human recombinant soluble TRAIL by R&D, USA; and mevastatin by Sigma, USA. METHODS: SWO-38 cells were separately incubated in TRAIL (100, 200, 300, 400, and 500 tJg/L) and mevastatin (5, 10, 20, 30, and 40 pmol/L) for 72 hours. In addition, SWO-38 cells were incubated in TRAIL (300 μg/L), mevastatin (30 μmol/L), and a solution containing both TRAIL and mevastatin for 12, 24, 48 and 72 hours. MAIN OUTCOME MEASURES: Cell proliferation was detected using methyl thiazolyl tetrazolium assay; cell apoptosis was observed using Hoechst 33258 staining and fluorescence microscopy and was measured using Annexin V/propidium iodide flow cytometry; TRAIL R1/DR4 and TRAIL R2/DR5 protein expressions levels were measured using indirect immunofluorescence staining combined with flow cytometry in the recombinant soluble TRAIL (rsTRAIL, 300 tJg/L), mevastatin (30 IJmol/L) and combination groups; TRAIL R1/DR4 and TRAIL R2/DR5 mRNA expression was detected using real-time polymerase chain reaction. RESULTS: rsTRAIL, mevastatin and their combination inhibited tumor proliferation in a time- and dose-dependent manner. The proliferation inhibitory rate and apoptosis rate of human SWO-38 cells in the combined group were significantly greater than the rsTRAIL or mevastatin alone group (P 〈 0.01). TRAIL R1/DR4 and TRAIL R2/DR5 protein and mRNA expressions were increased in the combination group compared with mevastatin or rsTRAIL alone after 72 hours (P 〈 0.01). CONCLUSION: Both rsTRAIL and mevastatin inhibit the proliferation and apoptosis of the human glioma cell line SWO-38, while their combination enhances the anti-tumor effect. The mechanism of action possibly correlates to the upregulation of TRAIL R1/DR4 and TRAIL R2/DR5 mRNA expression by mevastatin, thereby enhancing the cell sensitivity to rsTRAIL.展开更多
Studies have shown that tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)exhibits strong induction of apoptosis in human glioma cells.It remains unclear whether the mitochondrion pathway,an important ap...Studies have shown that tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)exhibits strong induction of apoptosis in human glioma cells.It remains unclear whether the mitochondrion pathway,an important apoptosis signaling pathway,is involved in TRAIL-induced glioma cell apoptosis.In the present study,in vitro cultured human glioma U87 cells were treated with human recombinant soluble TRAIL.Apoptosis of glioma U87 cells,mitochondrial transmembrane potential(Δψm),cytoplasmic cytochrome c concentration and changes in caspase-3,-8 and-9 activity following human recombinant soluble TRAIL treatment were investigated to determine the mechanism of glioma U87 cell apoptosis induced by TRAIL.Additionally,blocking caspase-8resulted in TRAIL-induced mitochondrion pathway activation,suggesting that TRAIL,through activating caspase-8,initiated a series of mitochondrial events and resulted in apoptosis of glioma U87 cells.展开更多
BACKGROUND: Human tumor necrosis factor-like molecule 1A (hTL1A) is a strong T helper cell type 1 (Thl) co-stimulator. Guillain-Barre syndrome (GBS) is an autoimmune disorder of the nervous system, which is med...BACKGROUND: Human tumor necrosis factor-like molecule 1A (hTL1A) is a strong T helper cell type 1 (Thl) co-stimulator. Guillain-Barre syndrome (GBS) is an autoimmune disorder of the nervous system, which is mediated by Thl cells. OBJECTIVE: To determine hTL1A expression in peripheral blood T lymphocytes of acute GBS children and the effects of hTL1A on secretion of interferon-γ. DESIGN, TIME AND SETTING: A randomized, controlled, neuroimmunological in vitro study was performed at the Central Laboratory of First Hospital of Jilin University, China from November 2005 to November 2007. MATERIALS: Venous blood samples were obtained from 6 healthy donors, aged 6-12 years (all routine blood examination items were normal), and 6 additional children with acute GBS, aged 6-12 years. The GBS children fell ill within 1 week and were not treated with hormones or immunoglobulin Purified recombinant human soluble tumor necrosis factor-like molecule 1A (rhsTL1A, 1 mg/mL, relative molecular mass 22 000, 6× His tag, soluble form) was supplied by the Central Laboratory of First Hospital of Jilin University, China. METHODS: Peripheral blood mononuclear cells were isolated from healthy donors using the standard Ficoll gradient centrifugation and were incubated in 96-well culture plates. The cells were assigned to the following groups: control (2 μg/mL phytohemagglutinin), 2μg/mL phytohemagglutinin + 25, 100 and 400 ng/mL rhsTL1A. T cell proliferation was quantified using the tritiated thymidine (3H-TdR) method. Serum interferon-γ levels in acute GBS children were detected by enzyme-linked immunosorbent assay (ELISA). The ratio of hTL1A-positive T cells to CD3-positive T cells in peripheral blood of acute GBS children was determined using flow cytometry. Following in vitro pre-activation of peripheral blood mononuclear cells by 2 μg/mL phytohemagglutinin, the peripheral blood mononuclear cells were treated with 400 ng/mL exogenous rhsTLIA. Finally, peripheral blood mononuclear cell-secreted interferon-γlevels were measured by ELISA. MAIN OUTCOME MEASURES: The following parameters were measured: rhsTLIA stimulation index to stimulate proliferation of T cells; the serum interferon-γ levels in acute GBS children; the ratio of hTL1A-positive cells to CD3-positive cells; the levels of interferon-γ secreted by peripheral blood mononuclear cells in acute GBS children, as well as rhsTL1A-stimulated interferon-γ levels. RESULTS: T cell proliferation assay revealed that the stimulation index in each rhsTL1A group was greater than the control group. The stimulation index of the 400 ng/mL rhsTL1A group was the greatest. Serum interferon-γ levels in acute GBS children were significantly greater than the control group (P 〈 0.05). The ratio of hTLIA+ CD3+ T cells to CD3+ T cells in acute GBS children was significantly greater than the control group (P 〈 0.01 ). Phytohemagglutinin stimulated peripheral blood mononuclear cells to a greater extent than 400 ng/mL rhsTL1A in the acute GBS group, and the secreted interferon-γ levels were significantly increased (P 〈 0.05). CONCLUSION: In T cells pre-activated with 2 μg/mL phytohemagglutinin, proliferation was effectively increased with 400 ng/mL rhsTL1A treatment. Expression of hTLIA was increased in activated T cells from peripheral blood of acute GBS children, followed by increased interferon-γ secretion. These mechanisms are considered to be part of the pathological process that induces the secretion of inflammatory cytokines in GBS syndrome.展开更多
AIM: To investigate the role of claudin 1 in the regulation of genes involved in cell migration and tumor necrosis factor alpha (TNF-α)-induced gene expression in human gastric adenocarcinoma cells.
Ulcerative colitis(UC)and Crohn’s disease(CD)are part of Inflammatory Bowel Diseases(IBD)and have pathophysiological processes such as bowel necrosis and enteric neurons and enteric glial cells.In addition,the main i...Ulcerative colitis(UC)and Crohn’s disease(CD)are part of Inflammatory Bowel Diseases(IBD)and have pathophysiological processes such as bowel necrosis and enteric neurons and enteric glial cells.In addition,the main inflammatory mediator is related to the tumor necrosis factor-alpha(TNF-α).TNF-αis a mediator of the intestinal inflammatory processes,thus being one of the main cytokines involved in the pathogenesis of IBD,however,its levels,when measured,are present in the serum of patients with IBD.In addition,TNF-αplays an important role in promoting inflammation,such as the production of interleukins(IL),for instance IL-1βand IL-6.There are two receptors for TNF as following:The tumor necrosis factor 1 receptor(TNFR1);and the tumor necrosis factor 2 receptor(TNFR2).They are involved in the pathogenesis of IBD and their receptors have been detected in IBD and their expression is correlated with disease activity.The soluble TNF form binds to the TNFR1 receptor with,and its activation results in a signaling cascade effects such as apoptosis,cell proliferation and cytokine secretion.In contrast,the transmembrane TNF form can bind both to TNFR1 and TNFR2.Recent studies have suggested that TNF-αis one of the main pro-inflammatory cytokines involved in the pathogenesis of IBD,since TNF levels are present in the serum of both patients with UC and CD.Intravenous and subcutaneous biologics targeting TNF-αhave revolutionized the treatment of IBD,thus becoming the best available agents to induce and maintain IBD remission.The application of antibodies aimed at neutralizing TNF-αin patients with IBD that induce a satisfactory clinical response in up to 60%of patients,and also induced long-term maintenance of disease remission in most patients.It has been suggested that anti-TNF-αagents inactivate the pro-inflammatory cytokine TNF-αby direct neutralization,i.e.,resulting in suppression of inflammation.However,anti-TNF-αantibodies perform more complex functions than a simple blockade.展开更多
BACKGROUND Inflammatory cytokines play a vital role in the occurrence of osteoarticular injury and inflammation. Whether inflammation-associated factors interleukin-1β(IL- 1β), IL-6, tumor necrosis factor-α(TNF-α)...BACKGROUND Inflammatory cytokines play a vital role in the occurrence of osteoarticular injury and inflammation. Whether inflammation-associated factors interleukin-1β(IL- 1β), IL-6, tumor necrosis factor-α(TNF-α) and vascular endothelial growth factor (VEGF) are involved in the pathogenesis of keen articular cartilage injury remains poorly understood. AIM To measure the levels of inflammatory factors [IL-1β, IL-6, TNF-α and VEGF] in patients with knee articular cartilage injury. METHODS Fifty-five patients with knee articular cartilage injury were selected as patient groups, who were divided into three grades [mild (n = 20), moderate (n = 19) and severe (n = 16)] according to disease severity and X-ray examinations. Meanwhile, 30 healthy individuals who underwent physical examination were selected as the control group. The levels of IL-1β, IL-6, TNF-α and VEGF were measured by ELISA and immunohistochemical staining. RESULTS Compared with the control group, patient groups displayed significantly higher levels of IL-1β, IL-6, TNF-α and VEGF, and the extent of increase was directly proportional to the severity of injury (P < 0.05). In addition, the number of cells with positive staining of IL-1β, IL-6, TNF-α and VEGF in the synovial membrane were significantly increased, along with increased disease severity (P < 0.05). After treatment, the scores of visual analogue scale and the Western Ontario and McMaster University of Orthopaedic Index in patient groups were 2.26 ± 1.13 and 15.56 ± 7.12 points, respectively, which were significantly lower than those before treatment (6.98 ± 1.32 and 49.48 ± 8.96). Correlation analysis suggested that IL-1β and TNF-α were positively correlated with VEGF. CONCLUSION IL-1β, IL-6, TNF-α and VEGF levels are increased in patients with knee articular cartilage injury, and are associated with the disease severity, indicating they might play an important role in the occurrence and development of knee articular cartilage injury. Furthermore, therapeutically targeting them might be a novel approach for the treatment of keen articular cartilage injury.展开更多
To investigate genetic factors that might help define which Crohn’s disease (CD) patients are likely to benefit from anti-tumor necrosis factor (TNF) therapy. METHODSThis was a prospective cohort study. Patients were...To investigate genetic factors that might help define which Crohn’s disease (CD) patients are likely to benefit from anti-tumor necrosis factor (TNF) therapy. METHODSThis was a prospective cohort study. Patients were recruited from a university digestive disease practice database. We included CD patients who received anti-TNF therapy, had available medical records (with information on treatment duration and efficacy) and who consented to participation. Patients with allergic reactions were excluded. Patients were grouped as ever-responders or non-responders. Genomic DNA was extracted from peripheral blood, and 7 single nucleotide polymorphisms (SNPs) were assessed. The main outcome measure (following exposure to the drug) was response to therapy. The patient genotypes were assessed as the predictors of outcome. Possible confounders and effect modifiers included age, gender, race, and socioeconomic status disease, as well as disease characteristics (such as Montreal criteria). RESULTS121 patients were included. Twenty-one were non-responders, and 100 were ever-responders. Fas ligand SNP (rs763110) genotype frequencies, TNF gene -308 SNP (rs1800629) genotype frequencies, and their combination, were significantly different between groups on multivariable analysis controlling for Montreal disease behavior and perianal disease. The odds of a patient with a Fas ligand CC genotype being a non-responder were four-fold higher as compared to a TC or TT genotype (P = 0.009, OR = 4.30, 95%CI: 1.45-12.80). The presence of the A (minor) TNF gene -308 allele correlated with three-fold higher odds of being a non-responder (P = 0.049, OR = 2.88, 95%CI: 1.01-8.22). Patients with the combination of the Fas ligand CC genotype and the TNF -308 A allele had nearly five-fold higher odds of being a non-responder (P = 0.015, OR = 4.76, 95%CI: 1.35-16.77). No difference was seen for the remaining SNPs. CONCLUSIONThe Fas-ligand SNP and TNF gene -308 SNP are associated with anti-TNF treatment response in CD and may help select patients likely to benefit from therapy.展开更多
Summary: To investigate whether interleukin-1β(IL-1β), tumor necrosis factor-α (TNF-α) and lipopolysaccharide (LPS) induce expression of monocyte chemoattractant protein-1 (MCP-1 ) mRNA and protein in calf aortic ...Summary: To investigate whether interleukin-1β(IL-1β), tumor necrosis factor-α (TNF-α) and lipopolysaccharide (LPS) induce expression of monocyte chemoattractant protein-1 (MCP-1 ) mRNA and protein in calf aortic smooth muscle cells(SMCs), calf aortic SMCs were cultured by a substrate-attached explant method. The cultured SMCs were used between the third to the fifth passage. After the cells became confluent, the SMCs were exposed to 2 ng/ml IL-1β, 20ng/ml TNF-1α and 100 ng/ml LPS respectively, and the total RNA of SMCs which were incubated for 4 h at 37℃ were extracted from the cells by using guanidinium isothiocyanate method. The expres- ion of MCP-1 mRNA in SMCs was detected by using dot blotting analysis using a probe of γ-32 P- end-labelled 35-mer oligonucleotide. After a 24-h incubation, the media conditioned by the cul- tured SMCs were collected. The MCP-1 protein content in the conditioned media was determined by using sandwich ELISA. The results were as follows: Dot blotting analysis showed that the cul- tured SMCs could express MCP-1 mRNA. After a 4-h exposure to IL-1β, TNF-α and LPS, the MCP-1 mRNA expression in SMCs was increased (3.6-fold, 2. 3-fold and 1. 6-fold, respectively). ELISA showed that the levels of MCP-1 protein in the conditioned media were also increased (2.9- fold, 1.7-fold and 1.1-fold, respectively). The results suggest that calf aortic SMCs could ex- press MCP-1 mRNA and protein. IL-1β and TNF-α can induce strong expression of MCP-1 mRNA and protein, and the former is more effective than the latter.展开更多
AIM:To determine the effect of tumor necrosis factor alpha(TNF-α) on intestinal permeability(IP) in mice with fulminant hepatic failure(FHF),and the expression of tight junction proteins.METHODS:We selected D-lactate...AIM:To determine the effect of tumor necrosis factor alpha(TNF-α) on intestinal permeability(IP) in mice with fulminant hepatic failure(FHF),and the expression of tight junction proteins.METHODS:We selected D-lactate as an index of IP,induced FHF using D-galactosamine/lipopolysaccharide and D-galactosamine/TNF-α,assessed the results using an enzymatic-spectrophotometric method,transmission electron microscopy,immunohistochemistry,Western blotting and real-time quantitative polymerase chain reaction.The effect of the administration of antiTNF-α immunoglobulin G(IgG) antibody,before the administration of D-galactosamine/lipopolysaccharide,on TNF-α was also assessed.RESULTS:IP was significantly increased in the mouse model of FHF 6 h after injection(13.57 ± 1.70 mg/L,13.02 ± 1.97 mg/L vs 3.76 ± 0.67 mg/L,P = 0.001).Electron microscopic analysis revealed tight junction(TJ) disruptions,epithelial cell swelling,and atrophy of intestinal villi.Expression of occludin and claudin-1 mRNA was significantly decreased in both FHF models(occludin:0.57 ± 0.159 fold vs baseline,P = 0.000;claudin-1:0.3067 ± 0.1291 fold vs baseline,P = 0.003),as were the distribution density of proteins in the intestinal mucosa and the levels of occludin and claudin-1 protein(occludin:0.61 ± 0.0473 fold vs baseline,P = 0.000;claudin-1:0.6633 ± 0.0328 fold vs baseline,P = 0.000).Prophylactic treatment with antiTNF-α IgG antibody prevented changes in IP(4.50 ± 0.97 mg/L vs 3.76 ± 0.67 mg/L,P = 0.791),intestinal tissue ultrastructure,and the mRNA levels of occludin and claudin-1 expression(occludin:0.8865 ± 0.0274 fold vs baseline,P = 0.505;claudin-1:0.85 ± 0.1437 fold vs baseline,P = 0.1),and in the protein levels(occludin:0.9467 ± 0.0285 fold vs baseline,P > 0.05;claudin-1:0.9533 ± 0.0186 fold vs baseline,P = 0.148).CONCLUSION:Increased in IP stemmed from the downregulation of the TJ proteins occludin and claudin-1,and destruction of the TJ in the colon,which were induced by TNF-α in FHF mice.展开更多
Objective:To analyze scrum leptin levels in patients with malaria falciparum and compare them with healthy controls and correlate with development and outcome of malaria infection.Methods:Sixty cases of malaria falcip...Objective:To analyze scrum leptin levels in patients with malaria falciparum and compare them with healthy controls and correlate with development and outcome of malaria infection.Methods:Sixty cases of malaria falciparum were included in this study as patients.Thirty healthy individuals of comparable age,racial and body mass index were taken as controls.All patients were diagnosed by clinical picture and the presence of malaria parasites in blood film.Estimation of liver function test,kidney function test,complete blood count,fasting blood sugar,fasting serum insulin,pro-inflammatory cytokine tumor necrosis factor alpha(TNFα)and interleukin 1(IL1),estimation of morning serum leptin and calculation of body mass index(kg/m^2)were done in both groups on the day of admission,on discharge and 7 d after discharge.Results:At admission,leptin levels were significantly higher in patients group than in control while lasting serum insulin levels were not significantly different between the two groups.There were significant increases as regard to TNFαand IL1 in malaria patients.Significant differences were observed between the control and the patient group for leptin,TNFαand IL1 at the time of admission and discharge.After discharge for 7 d.a significant decline in scrum leptin levels,TNFαand IL1 in the patients group was observed as compared with time of admission and time of discharge,a positive correlation between serum leptin levels and TNFαand IL1.Conclusions:Leptin hormone level might play an important role in development and outcome of malaria infection.展开更多
Most of the ocular tumors have poor prognosis, and they remain a difficult problem in the area of ophthalmology. With the rapid development of molecular biology and immunologic techniques and the deep research on ocul...Most of the ocular tumors have poor prognosis, and they remain a difficult problem in the area of ophthalmology. With the rapid development of molecular biology and immunologic techniques and the deep research on ocular tumor related genes, it becomes possible to diagnose and treat malignant tumors from the molecular level. The tumor necrosis factor related apoptosis-inducing ligand (TRAIL), a member of the tumor necrosis factor (TNF) super family, is a promising candidate, either alone or in combination with established cancer therapies, since it can initiate apoptosis through the activation of their death receptors. The ability of TRAIL to selectively induce apoptosis of transformed, virus-infected or tumor cells but not normal cells promotes the development of TRAIL-based cancer therapy. Here, we will review TRAIL and its receptors' structure, function, mechanism of action and application in ocular tumors therapy.展开更多
BACKGROUND The immunosuppressive capacity of mesenchymal stem cells(MSCs)is dependent on the“license”of several proinflammatory factors to express immunosuppressive factors such as programmed cell death 1 ligand 1(P...BACKGROUND The immunosuppressive capacity of mesenchymal stem cells(MSCs)is dependent on the“license”of several proinflammatory factors to express immunosuppressive factors such as programmed cell death 1 ligand 1(PD-L1),which determines the clinical therapeutic efficacy of MSCs for inflammatory or immune diseases.In MSCs,interferon-gamma(IFN-γ)is a key inducer of PD-L1 expression,which is synergistically enhanced by tumor necrosis factor-alpha(TNF-α);however,the underlying mechanism is unclear.AIM To reveal the mechanism of pretreated MSCs express high PD-L1 and explore the application of pretreated MSCs in ulcerative colitis.METHODS We assessed PD-L1 expression in human umbilical-cord-derived MSCs(hUC-MSCs)induced by IFN-γand TNF-α,alone or in combination.Additionally,we performed signal pathway inhibitor experiments as well as RNA interference experiments to elucidate the molecular mechanism by which IFN-γalone or in combination with TNF-αinduces PD-L1 expression.Moreover,we used luciferase reporter gene experiments to verify the binding sites of the transcription factors of each signal transduction pathway to the targeted gene promoters.Finally,we evaluated the immunosuppressive capacity of hUC-MSCs treated with IFN-γand TNF-αin both an in vitro mixed lymphocyte culture assay,and in vivo in mice with dextran sulfate sodium-induced acute colitis.RESULTS Our results suggest that IFN-γinduction alone upregulates PD-L1 expression in hUC-MSCs while TNF-αalone does not,and that the co-induction of IFN-γand TNF-αpromotes higher expression of PD-L1.IFN-γinduces hUCMSCs to express PD-L1,in which IFN-γactivates the JAK/STAT1 signaling pathway,up-regulates the expression of the interferon regulatory factor 1(IRF1)transcription factor,promotes the binding of IRF1 and the PD-L1 gene promoter,and finally promotes PD-L1 mRNA.Although TNF-αalone did not induce PD-L1 expression in hUCMSCs,the addition of TNF-αsignificantly enhanced IFN-γ-induced JAK/STAT1/IRF1 activation.TNF-αupregulated IFN-γreceptor expression through activation of the nuclear factor kappa-B signaling pathway,which significantly enhanced IFN-γsignaling.Finally,co-induced hUC-MSCs have a stronger inhibitory effect on lymphocyte proliferation,and significantly ameliorate weight loss,mucosal damage,inflammatory cell infiltration,and up-regulation of inflammatory factors in colitis mice.CONCLUSION Overall,our results suggest that IFN-γand TNF-αenhance both the immunosuppressive ability of hUC-MSCs and their efficacy in ulcerative colitis by synergistically inducing high expression of PD-L1.展开更多
BACKGROUND: Previous studies of curcumin have focused mainly on its cytotoxic properties for antitumor therapy. There are few studies addressing the application of curcumin in the prevention and treatment of nervous ...BACKGROUND: Previous studies of curcumin have focused mainly on its cytotoxic properties for antitumor therapy. There are few studies addressing the application of curcumin in the prevention and treatment of nervous system diseases. OBJECTIVE: To observe the protective effect of curcumin against tumor necrosis factor-alpha (TNF-α)-induced neuronal damage in the rat hippocampus and to explore the intervention effect of curcumin on Ca^2+ influx following neuronal damage. DESIGN, TIME AND SETTING: A cell morphological and physiological study was performed at the Institute of Brain Research, Medical College of Jinan University, China, from December 2006 to June 2007. MATERIALS: Curcumin (Sigma, USA) and TNF-α (Sigma, USA) were used in this study. METHODS: Hippocampal neurons were isolated from one-day neonatal rats and primarily cultured for 5 days. Following this they received 1 pmol/L curcumin and 100 ng/mL TNF-a pre-treatment. Dynamic morphological changes were observed for 1 hour by inverted microscopy. At 48 hours post-treatment, static morphological characteristics of the neurons were observed using inverted microscopy. Subsequently, hippocampal neurons were primarily cultured for 7 days, after receiving 1 pmol/L curcumJn and 4.5 ng/mL TNF-a pre-treatment. Intracellular free Ca^2+ was measured using Fluo 3/acetoxymethyl ester. MAIN OUTCOME MEASURES: Effects of curcumin on TNF-a-induced neuronal damage and Ca^2+ influx in the rat hippocampus were measured. RESULTS: Following curcumin treatment, TNF-a-induced neurons grew as normal. TNF-a induced a rapid Ca^2+ influx into the neuronal cytoplasm; however, Ca2+ fluorescence intensity only slightly increased when neurons were co-perfused with curcumin and TNF-α. CONCLUSION: Curcumin has a protective effect on rat hippocampal neurons possibly by reducing the TNF-α-induced rapid Ca^2+ influx into neuronal cytoplasm and by maintaining the Ca^2+ homeostasis.展开更多
AIM: To determine the expression statuses of tumor necrosis factor (TNF)-α, its receptors (TNF-R) and downstream effector molecules in human colorectal adenomas. METHODS: We measured the serum concentrations of TNF-...AIM: To determine the expression statuses of tumor necrosis factor (TNF)-α, its receptors (TNF-R) and downstream effector molecules in human colorectal adenomas. METHODS: We measured the serum concentrations of TNF-α and its receptors in 62 colorectal adenoma patients and 34 healthy controls. The protein expression of TNF-α, TNF-R1, TNF-R2 and downstream signals of the TNF receptors, such as c-Jun N-terminal kinase (JNK), nuclear factor-κ B and caspase-3, were also investigated in human colorectal adenomas and in normal colorectal mucosal tissues by immunohistochemistry. Immunofluorescence confocal microscopy was used to investigate the consistency of expression of TNF-R1 and phospho-JNK (p-JNK). RESULTS: The serum levels of soluble TNF-R1 (sTNF-R1) in adenoma patients were significantly higher than in the control group (3.67 ± 0.86 ng/mL vs 1.57 ± 0.72 ng/mL, P < 0.001). Receiver operating characteristic analysis revealed the high diagnostic sensitivity of TNF-R1 measurements (AUC was 0.928) for the diagnosis of adenoma, and the best cut-off level of TNF-R1 was 2.08 ng/mL, with a sensitivity of 93.4% and a specificity of 82.4%. There were no significant differences in the serum levels of TNF-α or sTNF-R2 between the two groups. Immunohistochemistry showed high levels of TNF-R1 and p-JNK expression in the epithelial cells of adenomas. Furthermore, a high incidence of co-localization of TNF-R1 and p-JNK was identified in adenoma tissue. CONCLUSION: TNF-R1 may be a promising biomarker of colorectal adenoma, and it may also play an important role in the very early stages of colorectal carcinogenesis.展开更多
BACKGROUND: Studies of several animal models of central nervous system diseases have shown that neural progenitor cells (NPCs) can migrate to injured tissues. Stromal cell-derived factor 1 alpha (SDF-la), and its...BACKGROUND: Studies of several animal models of central nervous system diseases have shown that neural progenitor cells (NPCs) can migrate to injured tissues. Stromal cell-derived factor 1 alpha (SDF-la), and its primary physiological receptor CXCR4, have been shown to contribute to this process. OBJECTIVE: To investigate migration efficacy of human NPCs toward a SDF-1α gradient, and the regulatory roles of tumor necrosis factor-α (TNF-α) and interleukin-8 (IL-8) in SDF-1α/CXCR4 axis-induced migration of NPCs. DESIGN, TIME AND SETTING: An in vitro, randomized, controlled, cellular and molecular biology study was performed at the Laboratory of Department of Cell Biology, Medical College of Soochow University between October 2005 and November 2007. MATERIALS: SDF-1α and mouse anti-human CXCR4 fusion antibody were purchased from R&D Systems, USA. TNF-αwas purchased from Biomyx Technology, USA and IL-8 was kindly provided by the Biotechnology Research Institute of Soochow University. METHODS: NPCs isolated from forebrain tissue of 9 to 10-week-old human fetuses were cultured in vitro. The cells were incubated with 0, 20, and 40 ng/mL TNF-α, or 0, 20, and 40 ng/mL IL-8, for 48 hours prior to migration assay. For antibody-blocking experiments, cells were further pretreated with 0, 20, and 40 μg/mL mouse anti-human CXCR4 fusion antibody for 2 hours. Subsequently, the transwell assay and CXCR4 blockade experiments were performed to evaluate migration of human NPCs toward a SDF-1α gradient. Serum-free culture medium without SDF-1α served as the negative control. MAIN OUTCOME MEASURES: The transwell assay was performed to evaluate migration of human NPCs toward a SDF-1α gradient, which was blocked by fusion antibody against CXCR4. In addition, CXCR4 expression in human NPCs stimulated by TNF-α and IL-8 was measured by flow cytometry. RESULTS: Results from the transwell assay demonstrated that SDF-1α was a strong chemoattractant for human NPCs (P 〈 0.01), and 20 ng/mL produced the highest levels of migration. Anti-human CXCR4 fusion antibody significantly blocked the chemotactic effect (P 〈 0.05). Flow cytometry results showed that treatment with TNF-α and IL-8 resulted in increased CXCR4 expression and greater chemotaxis efficiency of NPCs towards SDF-1α(P 〈 0.01). CONCLUSION: These results demonstrated that SDF-la significantly attracted NPCs in vitro, and neutralizing anti-CXCR4 antibody could block part of this chemotactic function. TNF-α and IL-8 increased chemotaxis efficiency of NPCs towards the SDF-1αgradient by upregulating CXCR4 expression in NPCs.展开更多
Objective: To investigate membrane tumor necrosis factor receptor 1 protein expression level in decidua and concentration of soluble tumor necrosis factor receptor 1 in serum in women with unexplained early spontaneou...Objective: To investigate membrane tumor necrosis factor receptor 1 protein expression level in decidua and concentration of soluble tumor necrosis factor receptor 1 in serum in women with unexplained early spontaneous abortion, threatened abortion, and compare the levels with healthy pregnant women. Methods: Thirty-seven women with unexplained early spontaneous abortion, 27 women with threatened abortion, and 34 healthy pregnant women undergoing artificial abortion of pregnancy at 6 - 10 weeks of gestation were selected. Decidual samples were collected when women were undergoing artificial abortion, and blood samples were collected at the same time. The level of membrane tumor necrosis factor receptor 1 in decidua was detected by flow cytometer, and the concentration of soluble tumor necrosis factor receptor 1 in sera was measured with an enzyme-linked immunosorbent assay. Results: The percentages of membrane tumor necrosis factor receptor 1 positive decidual cells were 16.42 ± 7.10 Mean ± SD for women with unexplained early spontaneous abortion and 13. 14 ± 6.30 for healthy pregnant women ( P < 0.05). Serum concentration of soluble tumor necrosis factor receptor 1 was significantly higher in women with unexplained early spontaneous abortion than in healthy pregnant women and in women with threatened abortion, and no difference was found between healthy pregnant women and women with threatened abortion. Conclusion: Women with unexplained early spontaneous abortion present significantly higher expression of tumor necrosis factor receptor 1 than healthy pregnant women, suggesting that over-expression of tumor necrosis factor receptor 1 may contribute to the development of early spontaneous abortion.展开更多
Hepatitis C virus(HCV)infection is an excellent immunological model for understanding the mechanisms developed by non-cytopathic viruses and tumors to evade the adaptative immune response.The antigen-specific cytotoxi...Hepatitis C virus(HCV)infection is an excellent immunological model for understanding the mechanisms developed by non-cytopathic viruses and tumors to evade the adaptative immune response.The antigen-specific cytotoxic T cell response is essential for keeping HCV under control,but during persistent infection,these cells become exhausted or even deleted.The exhaustion process is progressive and depends on the infection duration and level of antigenemia.During high antigenic load and long duration of infection,T cells become extremely exhausted and ultimately disappear due to apoptosis.The development of exhaustion involves the impairment of positive co-stimulation induced by regulatory cytokines,such as transforming growth factor beta 1.This cytokine downregulates tumor necrosis factor receptor(TNFR)-associated factor 1(TRAF1),the signal transducer of the T cell co-stimulatory molecule TNFR superfamily member 9(known as 4-1BB).This impairment correlates with the low reactivity of T cells and an exhaustion phenotype.Treatment with interleukin-7 in vitro restores TRAF1 expression and rescues T cell effector function.The process of TRAF1 loss and its in vitro recovery is hierarchical,and more affected by severe disease progression.In conclusion,TRAF1 dynamics on T cells define a new pathogenic model that describes some aspects of the natural history of HCV,and sheds light on novel immunotherapy strategies for chronic viral infections and cancer.展开更多
BACKGROUND End-stage liver disease caused by non-alcoholic steatohepatitis(NASH)is the second leading indication for liver transplantation.To date,only moderately effective pharmacotherapies exist to treat NASH.Unders...BACKGROUND End-stage liver disease caused by non-alcoholic steatohepatitis(NASH)is the second leading indication for liver transplantation.To date,only moderately effective pharmacotherapies exist to treat NASH.Understanding the pathogenesis of NASH is therefore crucial for the development of new therapies.The inflammatory cytokine tumor necrosis factor alpha(TNF-α)is important for the progression of liver disease.TNF signaling via TNF receptor 1(TNFR1)has been hypothesized to be important for the development of NASH and hepatocellular carcinoma in whole-body knockout animal models.AIM To investigate the role of TNFR1 signaling in hepatocytes for steatohepatitis development in a mouse model of diet-induced NASH.METHODS NASH was induced by a western-style fast-food diet in mice deficient for TNFR1 in hepatocytes(TNFR1ΔHEP)and their wild-type littermates(TNFR1fl/fl).Glucose tolerance was assessed after 18 wk and insulin resistance after 19 wk of feeding.After 20 wk mice were assessed for features of NASH and the metabolic syndrome such as liver weight,liver steatosis,liver fibrosis and markers of liver inflammation.RESULTS Obesity,liver injury,inflammation,steatosis and fibrosis was not different between TNFR1ΔHEP and TNFR1fl/fl mice.However,Tnfr1 deficiency in hepatocytes protected against glucose intolerance and insulin resistance.CONCLUSION Our results indicate that deficiency of TNFR1 signaling in hepatocytes does not protect from diet-induced NASH.However,improved insulin resistance in this model strengthens the role of the liver in glucose homeostasis.展开更多
The course and severity of periodontitis can be significantly affected by bacterial virulence as well as host immunity dysfunction. Periodontal tissue destruction has been proved to result from cascade of cytokines sy...The course and severity of periodontitis can be significantly affected by bacterial virulence as well as host immunity dysfunction. Periodontal tissue destruction has been proved to result from cascade of cytokines synthesized by reactive cells upon stimulation by pathogenic bacteria and lipopolysaccharides within their cell membranes. The clinical use of genetically programmed cells, producing substances blocking IL-1, based on recombinant IL-1 antagonist, as well as cytokines activating fibroblasts and osteoblasts to regenerate the destroyed periodontal tissue could prove alternative to the conventional treatment. Another cytokine of interest in respect to periodontitis ethiopathogenesis is soluble tumor necrosis factor receptor I (sTNF RI). Observation of soluble TNF receptors as physiologic inhibitors of TNF led to its administration in therapeutic process as well as in therapy selected cases of aggressive periodontitis.展开更多
基金Key Program of Tenth Five-Year Plan and the 211 Key Subject Construction Foundation, No. 2002-2
文摘BACKGROUND: Receptors for tumor necrosis factor related apoptosis inducing ligand (TRAIL) include death receptor 4, death receptor 5, decoy receptor 1, and decoy receptor 2. Activation of death receptor 4 and 5 selectively kills tumor cells. OBJECTIVE: To detect TRAIL receptor expression in glioblastoma by immunohistochemistry and RT-PCR, and to compare this expression to that in normal brain tissue. DESIGN: Observational analysis. SETTING: Department of Pathology, the First Affiliated Hospital of Zhengzhou University; Henan Tumor Pathology Key Laboratory. PARTICIPANTS: Twenty-five patients (17 males and 8 females) who received glioblastoma resection were selected from the Fifth Affiliated Hospital of Zhengzhou University, between September 2003 to June 2004. All glioblastoma samples were diagnosed pathologically. Twenty patients (12 males and 8 females) with craniocerebral injury who received normal brain tissue resection were selected in the same time period. There were no significant differences in sex and age between glioblastoma patients or between craniocerebral injury patients (P 〉 0.05). All patients and appropriate relatives provided informed consent, and this study was approved by the local research ethics committee. METHODS: Polyclonal antibody against TRAIL receptors and an immunohistochemical kit (batch number: 200502) were purchased from Boster Company, Wuhan. Immunohistochemistry: Expression of death receptor 4, death receptor 5, decoy receptor l, and decoy receptor 2 were observed in both glioblastoma and normal brain tissue. The experiment was performed according to the kit instructions, and positive staining was brown-yellow. Assessment: There were no positive signals (-); weakly positive signals, positive cells 〈 25% (+); weakly positive signals, positive cells 25%-50% (++); strongly positive signals, positive cells 50%-75% (+++); strongly positive signals, positive cells 〉 75% (++++). Evaluation: Expression levels of TRAIL receptors were estimated in both normal brain tissue and glioblastoma. Expression of decoy receptor 1 and decoy receptor 2 mRNA in glioblastoma were detected by reverse transcription polymerase chain reaction, and expression of decoy receptor in glioblastoma was estimated. MAIN OUTCOME MEASURES: Comparison of death receptor and decoy receptor protein expression between glioblastoma and normal brain tissue; decoy receptor mRNA expression in glioblastoma. RESULTS: Death receptor protein expression was strongly positive (+++) in glioblastoma, while it was weakly positive (+, ++) in normal brain tissue. Therefore, expression rate of death receptor protein in the glioblastoma was significantly higher than that in the normal brain tissue (.~ 2 = 18.48, 23.03, P 〈 0.01). Decoy receptor protein expression in the glioblastoma was significantly lower than that in the normal brain tissue ( x2 = 6.65, 18.76, P 〈 0.01). The level of decoy receptor mRNA expression in glioblastoma was significantly higher than those of protein expression ( x 2 = 9.82, 10.09, P〈 0.01). CONCLUSION: High expression of death receptor and low expression of decoy receptor are frequently observed in glioblastoma, suggesting that TRAIL receptor genes show an anti-tumor and expressive response during the initiation and development of the tumor. There are significant differences in decoy receptor expression between normal brain tissue and glioblastoma, suggesting that the restricted expression of decoy receptor in glioblastoma is regulated at the post-transcriptional level.
基金the National Natural Science Foundation of China, No. 30772537
文摘BACKGROUND: Previous studies have reported that statins are less toxic to the human body and have greater antitumor activity; however, few studies have addressed the antitumor effect of statins combined with tumor necrosis factor-related apoptosis inducing ligand (TRAIL). OBJECTIVE: To explore the effect of TRAIL combined with mevastatin on the proliferation and apoptotic cell death of a human glioma cell line SWO-38, and to study its mechanism of action. DESIGN, TIME AND SETTING: An in vitro control experiment was performed at the Central Laboratory of the Third Hospital Affiliated to Sun Yat-sen University, between January and April 2009. MATERIALS: The human SWO-38 cell line was provided by Cell Research, Department of Animal Experimental Center of Sun Yat-sen University; human recombinant soluble TRAIL by R&D, USA; and mevastatin by Sigma, USA. METHODS: SWO-38 cells were separately incubated in TRAIL (100, 200, 300, 400, and 500 tJg/L) and mevastatin (5, 10, 20, 30, and 40 pmol/L) for 72 hours. In addition, SWO-38 cells were incubated in TRAIL (300 μg/L), mevastatin (30 μmol/L), and a solution containing both TRAIL and mevastatin for 12, 24, 48 and 72 hours. MAIN OUTCOME MEASURES: Cell proliferation was detected using methyl thiazolyl tetrazolium assay; cell apoptosis was observed using Hoechst 33258 staining and fluorescence microscopy and was measured using Annexin V/propidium iodide flow cytometry; TRAIL R1/DR4 and TRAIL R2/DR5 protein expressions levels were measured using indirect immunofluorescence staining combined with flow cytometry in the recombinant soluble TRAIL (rsTRAIL, 300 tJg/L), mevastatin (30 IJmol/L) and combination groups; TRAIL R1/DR4 and TRAIL R2/DR5 mRNA expression was detected using real-time polymerase chain reaction. RESULTS: rsTRAIL, mevastatin and their combination inhibited tumor proliferation in a time- and dose-dependent manner. The proliferation inhibitory rate and apoptosis rate of human SWO-38 cells in the combined group were significantly greater than the rsTRAIL or mevastatin alone group (P 〈 0.01). TRAIL R1/DR4 and TRAIL R2/DR5 protein and mRNA expressions were increased in the combination group compared with mevastatin or rsTRAIL alone after 72 hours (P 〈 0.01). CONCLUSION: Both rsTRAIL and mevastatin inhibit the proliferation and apoptosis of the human glioma cell line SWO-38, while their combination enhances the anti-tumor effect. The mechanism of action possibly correlates to the upregulation of TRAIL R1/DR4 and TRAIL R2/DR5 mRNA expression by mevastatin, thereby enhancing the cell sensitivity to rsTRAIL.
基金the National Natural Science Foundation of China, No. 30672409the Science and Technology Foundation Program of Guangdong Province, No. 2006B36003017
文摘Studies have shown that tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)exhibits strong induction of apoptosis in human glioma cells.It remains unclear whether the mitochondrion pathway,an important apoptosis signaling pathway,is involved in TRAIL-induced glioma cell apoptosis.In the present study,in vitro cultured human glioma U87 cells were treated with human recombinant soluble TRAIL.Apoptosis of glioma U87 cells,mitochondrial transmembrane potential(Δψm),cytoplasmic cytochrome c concentration and changes in caspase-3,-8 and-9 activity following human recombinant soluble TRAIL treatment were investigated to determine the mechanism of glioma U87 cell apoptosis induced by TRAIL.Additionally,blocking caspase-8resulted in TRAIL-induced mitochondrion pathway activation,suggesting that TRAIL,through activating caspase-8,initiated a series of mitochondrial events and resulted in apoptosis of glioma U87 cells.
基金Supported by:the Program of the Key Laboratory of Health Department of Jilin Province, No.2006079the Fortieth National Post-Doctoral Scientific Foundation,No. 20060400893
文摘BACKGROUND: Human tumor necrosis factor-like molecule 1A (hTL1A) is a strong T helper cell type 1 (Thl) co-stimulator. Guillain-Barre syndrome (GBS) is an autoimmune disorder of the nervous system, which is mediated by Thl cells. OBJECTIVE: To determine hTL1A expression in peripheral blood T lymphocytes of acute GBS children and the effects of hTL1A on secretion of interferon-γ. DESIGN, TIME AND SETTING: A randomized, controlled, neuroimmunological in vitro study was performed at the Central Laboratory of First Hospital of Jilin University, China from November 2005 to November 2007. MATERIALS: Venous blood samples were obtained from 6 healthy donors, aged 6-12 years (all routine blood examination items were normal), and 6 additional children with acute GBS, aged 6-12 years. The GBS children fell ill within 1 week and were not treated with hormones or immunoglobulin Purified recombinant human soluble tumor necrosis factor-like molecule 1A (rhsTL1A, 1 mg/mL, relative molecular mass 22 000, 6× His tag, soluble form) was supplied by the Central Laboratory of First Hospital of Jilin University, China. METHODS: Peripheral blood mononuclear cells were isolated from healthy donors using the standard Ficoll gradient centrifugation and were incubated in 96-well culture plates. The cells were assigned to the following groups: control (2 μg/mL phytohemagglutinin), 2μg/mL phytohemagglutinin + 25, 100 and 400 ng/mL rhsTL1A. T cell proliferation was quantified using the tritiated thymidine (3H-TdR) method. Serum interferon-γ levels in acute GBS children were detected by enzyme-linked immunosorbent assay (ELISA). The ratio of hTL1A-positive T cells to CD3-positive T cells in peripheral blood of acute GBS children was determined using flow cytometry. Following in vitro pre-activation of peripheral blood mononuclear cells by 2 μg/mL phytohemagglutinin, the peripheral blood mononuclear cells were treated with 400 ng/mL exogenous rhsTLIA. Finally, peripheral blood mononuclear cell-secreted interferon-γlevels were measured by ELISA. MAIN OUTCOME MEASURES: The following parameters were measured: rhsTLIA stimulation index to stimulate proliferation of T cells; the serum interferon-γ levels in acute GBS children; the ratio of hTL1A-positive cells to CD3-positive cells; the levels of interferon-γ secreted by peripheral blood mononuclear cells in acute GBS children, as well as rhsTL1A-stimulated interferon-γ levels. RESULTS: T cell proliferation assay revealed that the stimulation index in each rhsTL1A group was greater than the control group. The stimulation index of the 400 ng/mL rhsTL1A group was the greatest. Serum interferon-γ levels in acute GBS children were significantly greater than the control group (P 〈 0.05). The ratio of hTLIA+ CD3+ T cells to CD3+ T cells in acute GBS children was significantly greater than the control group (P 〈 0.01 ). Phytohemagglutinin stimulated peripheral blood mononuclear cells to a greater extent than 400 ng/mL rhsTL1A in the acute GBS group, and the secreted interferon-γ levels were significantly increased (P 〈 0.05). CONCLUSION: In T cells pre-activated with 2 μg/mL phytohemagglutinin, proliferation was effectively increased with 400 ng/mL rhsTL1A treatment. Expression of hTLIA was increased in activated T cells from peripheral blood of acute GBS children, followed by increased interferon-γ secretion. These mechanisms are considered to be part of the pathological process that induces the secretion of inflammatory cytokines in GBS syndrome.
基金Supported by Grants-in-Aid for Young Scientists(B)No.22791295,No.23791557 and No.24791440Grant-in-Aid for Scientific Research(C)from the Japan Society for the Promotion of Science,No.22591464 and No.24591957
文摘AIM: To investigate the role of claudin 1 in the regulation of genes involved in cell migration and tumor necrosis factor alpha (TNF-α)-induced gene expression in human gastric adenocarcinoma cells.
基金Research Support Foundation of the State of São Paulo(FAPESP,Brazil),No.2014/25927-2,No.2018/07862-1National Council for Scientific and Technological Development(CNPq,Brazil)Higher Education Personnel Improvement Coordination(CAPES,Brazil).
文摘Ulcerative colitis(UC)and Crohn’s disease(CD)are part of Inflammatory Bowel Diseases(IBD)and have pathophysiological processes such as bowel necrosis and enteric neurons and enteric glial cells.In addition,the main inflammatory mediator is related to the tumor necrosis factor-alpha(TNF-α).TNF-αis a mediator of the intestinal inflammatory processes,thus being one of the main cytokines involved in the pathogenesis of IBD,however,its levels,when measured,are present in the serum of patients with IBD.In addition,TNF-αplays an important role in promoting inflammation,such as the production of interleukins(IL),for instance IL-1βand IL-6.There are two receptors for TNF as following:The tumor necrosis factor 1 receptor(TNFR1);and the tumor necrosis factor 2 receptor(TNFR2).They are involved in the pathogenesis of IBD and their receptors have been detected in IBD and their expression is correlated with disease activity.The soluble TNF form binds to the TNFR1 receptor with,and its activation results in a signaling cascade effects such as apoptosis,cell proliferation and cytokine secretion.In contrast,the transmembrane TNF form can bind both to TNFR1 and TNFR2.Recent studies have suggested that TNF-αis one of the main pro-inflammatory cytokines involved in the pathogenesis of IBD,since TNF levels are present in the serum of both patients with UC and CD.Intravenous and subcutaneous biologics targeting TNF-αhave revolutionized the treatment of IBD,thus becoming the best available agents to induce and maintain IBD remission.The application of antibodies aimed at neutralizing TNF-αin patients with IBD that induce a satisfactory clinical response in up to 60%of patients,and also induced long-term maintenance of disease remission in most patients.It has been suggested that anti-TNF-αagents inactivate the pro-inflammatory cytokine TNF-αby direct neutralization,i.e.,resulting in suppression of inflammation.However,anti-TNF-αantibodies perform more complex functions than a simple blockade.
文摘BACKGROUND Inflammatory cytokines play a vital role in the occurrence of osteoarticular injury and inflammation. Whether inflammation-associated factors interleukin-1β(IL- 1β), IL-6, tumor necrosis factor-α(TNF-α) and vascular endothelial growth factor (VEGF) are involved in the pathogenesis of keen articular cartilage injury remains poorly understood. AIM To measure the levels of inflammatory factors [IL-1β, IL-6, TNF-α and VEGF] in patients with knee articular cartilage injury. METHODS Fifty-five patients with knee articular cartilage injury were selected as patient groups, who were divided into three grades [mild (n = 20), moderate (n = 19) and severe (n = 16)] according to disease severity and X-ray examinations. Meanwhile, 30 healthy individuals who underwent physical examination were selected as the control group. The levels of IL-1β, IL-6, TNF-α and VEGF were measured by ELISA and immunohistochemical staining. RESULTS Compared with the control group, patient groups displayed significantly higher levels of IL-1β, IL-6, TNF-α and VEGF, and the extent of increase was directly proportional to the severity of injury (P < 0.05). In addition, the number of cells with positive staining of IL-1β, IL-6, TNF-α and VEGF in the synovial membrane were significantly increased, along with increased disease severity (P < 0.05). After treatment, the scores of visual analogue scale and the Western Ontario and McMaster University of Orthopaedic Index in patient groups were 2.26 ± 1.13 and 15.56 ± 7.12 points, respectively, which were significantly lower than those before treatment (6.98 ± 1.32 and 49.48 ± 8.96). Correlation analysis suggested that IL-1β and TNF-α were positively correlated with VEGF. CONCLUSION IL-1β, IL-6, TNF-α and VEGF levels are increased in patients with knee articular cartilage injury, and are associated with the disease severity, indicating they might play an important role in the occurrence and development of knee articular cartilage injury. Furthermore, therapeutically targeting them might be a novel approach for the treatment of keen articular cartilage injury.
文摘To investigate genetic factors that might help define which Crohn’s disease (CD) patients are likely to benefit from anti-tumor necrosis factor (TNF) therapy. METHODSThis was a prospective cohort study. Patients were recruited from a university digestive disease practice database. We included CD patients who received anti-TNF therapy, had available medical records (with information on treatment duration and efficacy) and who consented to participation. Patients with allergic reactions were excluded. Patients were grouped as ever-responders or non-responders. Genomic DNA was extracted from peripheral blood, and 7 single nucleotide polymorphisms (SNPs) were assessed. The main outcome measure (following exposure to the drug) was response to therapy. The patient genotypes were assessed as the predictors of outcome. Possible confounders and effect modifiers included age, gender, race, and socioeconomic status disease, as well as disease characteristics (such as Montreal criteria). RESULTS121 patients were included. Twenty-one were non-responders, and 100 were ever-responders. Fas ligand SNP (rs763110) genotype frequencies, TNF gene -308 SNP (rs1800629) genotype frequencies, and their combination, were significantly different between groups on multivariable analysis controlling for Montreal disease behavior and perianal disease. The odds of a patient with a Fas ligand CC genotype being a non-responder were four-fold higher as compared to a TC or TT genotype (P = 0.009, OR = 4.30, 95%CI: 1.45-12.80). The presence of the A (minor) TNF gene -308 allele correlated with three-fold higher odds of being a non-responder (P = 0.049, OR = 2.88, 95%CI: 1.01-8.22). Patients with the combination of the Fas ligand CC genotype and the TNF -308 A allele had nearly five-fold higher odds of being a non-responder (P = 0.015, OR = 4.76, 95%CI: 1.35-16.77). No difference was seen for the remaining SNPs. CONCLUSIONThe Fas-ligand SNP and TNF gene -308 SNP are associated with anti-TNF treatment response in CD and may help select patients likely to benefit from therapy.
基金This project was supported by a grant from National Natural Science Foundation of China !(No. 39470289).
文摘Summary: To investigate whether interleukin-1β(IL-1β), tumor necrosis factor-α (TNF-α) and lipopolysaccharide (LPS) induce expression of monocyte chemoattractant protein-1 (MCP-1 ) mRNA and protein in calf aortic smooth muscle cells(SMCs), calf aortic SMCs were cultured by a substrate-attached explant method. The cultured SMCs were used between the third to the fifth passage. After the cells became confluent, the SMCs were exposed to 2 ng/ml IL-1β, 20ng/ml TNF-1α and 100 ng/ml LPS respectively, and the total RNA of SMCs which were incubated for 4 h at 37℃ were extracted from the cells by using guanidinium isothiocyanate method. The expres- ion of MCP-1 mRNA in SMCs was detected by using dot blotting analysis using a probe of γ-32 P- end-labelled 35-mer oligonucleotide. After a 24-h incubation, the media conditioned by the cul- tured SMCs were collected. The MCP-1 protein content in the conditioned media was determined by using sandwich ELISA. The results were as follows: Dot blotting analysis showed that the cul- tured SMCs could express MCP-1 mRNA. After a 4-h exposure to IL-1β, TNF-α and LPS, the MCP-1 mRNA expression in SMCs was increased (3.6-fold, 2. 3-fold and 1. 6-fold, respectively). ELISA showed that the levels of MCP-1 protein in the conditioned media were also increased (2.9- fold, 1.7-fold and 1.1-fold, respectively). The results suggest that calf aortic SMCs could ex- press MCP-1 mRNA and protein. IL-1β and TNF-α can induce strong expression of MCP-1 mRNA and protein, and the former is more effective than the latter.
基金Supported by National Ministry of Health of China,No.97100252
文摘AIM:To determine the effect of tumor necrosis factor alpha(TNF-α) on intestinal permeability(IP) in mice with fulminant hepatic failure(FHF),and the expression of tight junction proteins.METHODS:We selected D-lactate as an index of IP,induced FHF using D-galactosamine/lipopolysaccharide and D-galactosamine/TNF-α,assessed the results using an enzymatic-spectrophotometric method,transmission electron microscopy,immunohistochemistry,Western blotting and real-time quantitative polymerase chain reaction.The effect of the administration of antiTNF-α immunoglobulin G(IgG) antibody,before the administration of D-galactosamine/lipopolysaccharide,on TNF-α was also assessed.RESULTS:IP was significantly increased in the mouse model of FHF 6 h after injection(13.57 ± 1.70 mg/L,13.02 ± 1.97 mg/L vs 3.76 ± 0.67 mg/L,P = 0.001).Electron microscopic analysis revealed tight junction(TJ) disruptions,epithelial cell swelling,and atrophy of intestinal villi.Expression of occludin and claudin-1 mRNA was significantly decreased in both FHF models(occludin:0.57 ± 0.159 fold vs baseline,P = 0.000;claudin-1:0.3067 ± 0.1291 fold vs baseline,P = 0.003),as were the distribution density of proteins in the intestinal mucosa and the levels of occludin and claudin-1 protein(occludin:0.61 ± 0.0473 fold vs baseline,P = 0.000;claudin-1:0.6633 ± 0.0328 fold vs baseline,P = 0.000).Prophylactic treatment with antiTNF-α IgG antibody prevented changes in IP(4.50 ± 0.97 mg/L vs 3.76 ± 0.67 mg/L,P = 0.791),intestinal tissue ultrastructure,and the mRNA levels of occludin and claudin-1 expression(occludin:0.8865 ± 0.0274 fold vs baseline,P = 0.505;claudin-1:0.85 ± 0.1437 fold vs baseline,P = 0.1),and in the protein levels(occludin:0.9467 ± 0.0285 fold vs baseline,P > 0.05;claudin-1:0.9533 ± 0.0186 fold vs baseline,P = 0.148).CONCLUSION:Increased in IP stemmed from the downregulation of the TJ proteins occludin and claudin-1,and destruction of the TJ in the colon,which were induced by TNF-α in FHF mice.
基金supported by College of Health Sciences(Grant No,HS-10-01)
文摘Objective:To analyze scrum leptin levels in patients with malaria falciparum and compare them with healthy controls and correlate with development and outcome of malaria infection.Methods:Sixty cases of malaria falciparum were included in this study as patients.Thirty healthy individuals of comparable age,racial and body mass index were taken as controls.All patients were diagnosed by clinical picture and the presence of malaria parasites in blood film.Estimation of liver function test,kidney function test,complete blood count,fasting blood sugar,fasting serum insulin,pro-inflammatory cytokine tumor necrosis factor alpha(TNFα)and interleukin 1(IL1),estimation of morning serum leptin and calculation of body mass index(kg/m^2)were done in both groups on the day of admission,on discharge and 7 d after discharge.Results:At admission,leptin levels were significantly higher in patients group than in control while lasting serum insulin levels were not significantly different between the two groups.There were significant increases as regard to TNFαand IL1 in malaria patients.Significant differences were observed between the control and the patient group for leptin,TNFαand IL1 at the time of admission and discharge.After discharge for 7 d.a significant decline in scrum leptin levels,TNFαand IL1 in the patients group was observed as compared with time of admission and time of discharge,a positive correlation between serum leptin levels and TNFαand IL1.Conclusions:Leptin hormone level might play an important role in development and outcome of malaria infection.
文摘Most of the ocular tumors have poor prognosis, and they remain a difficult problem in the area of ophthalmology. With the rapid development of molecular biology and immunologic techniques and the deep research on ocular tumor related genes, it becomes possible to diagnose and treat malignant tumors from the molecular level. The tumor necrosis factor related apoptosis-inducing ligand (TRAIL), a member of the tumor necrosis factor (TNF) super family, is a promising candidate, either alone or in combination with established cancer therapies, since it can initiate apoptosis through the activation of their death receptors. The ability of TRAIL to selectively induce apoptosis of transformed, virus-infected or tumor cells but not normal cells promotes the development of TRAIL-based cancer therapy. Here, we will review TRAIL and its receptors' structure, function, mechanism of action and application in ocular tumors therapy.
基金Supported by the National Natural Science Foundation of China,No.81871568,No.32100643COVID-19 Infection and Prevention Emergency Special Project of Chongqing Education Commission,No.KYYJ202009.
文摘BACKGROUND The immunosuppressive capacity of mesenchymal stem cells(MSCs)is dependent on the“license”of several proinflammatory factors to express immunosuppressive factors such as programmed cell death 1 ligand 1(PD-L1),which determines the clinical therapeutic efficacy of MSCs for inflammatory or immune diseases.In MSCs,interferon-gamma(IFN-γ)is a key inducer of PD-L1 expression,which is synergistically enhanced by tumor necrosis factor-alpha(TNF-α);however,the underlying mechanism is unclear.AIM To reveal the mechanism of pretreated MSCs express high PD-L1 and explore the application of pretreated MSCs in ulcerative colitis.METHODS We assessed PD-L1 expression in human umbilical-cord-derived MSCs(hUC-MSCs)induced by IFN-γand TNF-α,alone or in combination.Additionally,we performed signal pathway inhibitor experiments as well as RNA interference experiments to elucidate the molecular mechanism by which IFN-γalone or in combination with TNF-αinduces PD-L1 expression.Moreover,we used luciferase reporter gene experiments to verify the binding sites of the transcription factors of each signal transduction pathway to the targeted gene promoters.Finally,we evaluated the immunosuppressive capacity of hUC-MSCs treated with IFN-γand TNF-αin both an in vitro mixed lymphocyte culture assay,and in vivo in mice with dextran sulfate sodium-induced acute colitis.RESULTS Our results suggest that IFN-γinduction alone upregulates PD-L1 expression in hUC-MSCs while TNF-αalone does not,and that the co-induction of IFN-γand TNF-αpromotes higher expression of PD-L1.IFN-γinduces hUCMSCs to express PD-L1,in which IFN-γactivates the JAK/STAT1 signaling pathway,up-regulates the expression of the interferon regulatory factor 1(IRF1)transcription factor,promotes the binding of IRF1 and the PD-L1 gene promoter,and finally promotes PD-L1 mRNA.Although TNF-αalone did not induce PD-L1 expression in hUCMSCs,the addition of TNF-αsignificantly enhanced IFN-γ-induced JAK/STAT1/IRF1 activation.TNF-αupregulated IFN-γreceptor expression through activation of the nuclear factor kappa-B signaling pathway,which significantly enhanced IFN-γsignaling.Finally,co-induced hUC-MSCs have a stronger inhibitory effect on lymphocyte proliferation,and significantly ameliorate weight loss,mucosal damage,inflammatory cell infiltration,and up-regulation of inflammatory factors in colitis mice.CONCLUSION Overall,our results suggest that IFN-γand TNF-αenhance both the immunosuppressive ability of hUC-MSCs and their efficacy in ulcerative colitis by synergistically inducing high expression of PD-L1.
基金the grant from Medical Science Foundation of Guangdong Province,No.A2006334the Natural Science Foundation of Guangdong Province,No.06105246,No.9151040701000008the Science and Technology Project of Guangzhou City,No.2007J1-C0041
文摘BACKGROUND: Previous studies of curcumin have focused mainly on its cytotoxic properties for antitumor therapy. There are few studies addressing the application of curcumin in the prevention and treatment of nervous system diseases. OBJECTIVE: To observe the protective effect of curcumin against tumor necrosis factor-alpha (TNF-α)-induced neuronal damage in the rat hippocampus and to explore the intervention effect of curcumin on Ca^2+ influx following neuronal damage. DESIGN, TIME AND SETTING: A cell morphological and physiological study was performed at the Institute of Brain Research, Medical College of Jinan University, China, from December 2006 to June 2007. MATERIALS: Curcumin (Sigma, USA) and TNF-α (Sigma, USA) were used in this study. METHODS: Hippocampal neurons were isolated from one-day neonatal rats and primarily cultured for 5 days. Following this they received 1 pmol/L curcumin and 100 ng/mL TNF-a pre-treatment. Dynamic morphological changes were observed for 1 hour by inverted microscopy. At 48 hours post-treatment, static morphological characteristics of the neurons were observed using inverted microscopy. Subsequently, hippocampal neurons were primarily cultured for 7 days, after receiving 1 pmol/L curcumJn and 4.5 ng/mL TNF-a pre-treatment. Intracellular free Ca^2+ was measured using Fluo 3/acetoxymethyl ester. MAIN OUTCOME MEASURES: Effects of curcumin on TNF-a-induced neuronal damage and Ca^2+ influx in the rat hippocampus were measured. RESULTS: Following curcumin treatment, TNF-a-induced neurons grew as normal. TNF-a induced a rapid Ca^2+ influx into the neuronal cytoplasm; however, Ca2+ fluorescence intensity only slightly increased when neurons were co-perfused with curcumin and TNF-α. CONCLUSION: Curcumin has a protective effect on rat hippocampal neurons possibly by reducing the TNF-α-induced rapid Ca^2+ influx into neuronal cytoplasm and by maintaining the Ca^2+ homeostasis.
基金Supported by Grant-in-Aid for Research from the Third-Term Comprehensive Control Research for Cancer Center of the Ministry of Health, Labor and Welfare, JapanGrant from the Ministry of Education, Culture, Sports, Science and Technology, Japan(KIBAN-B)the "Collaborative Development of Innovative Seeds" Grant Program from the Japan Science and Technology Agency
文摘AIM: To determine the expression statuses of tumor necrosis factor (TNF)-α, its receptors (TNF-R) and downstream effector molecules in human colorectal adenomas. METHODS: We measured the serum concentrations of TNF-α and its receptors in 62 colorectal adenoma patients and 34 healthy controls. The protein expression of TNF-α, TNF-R1, TNF-R2 and downstream signals of the TNF receptors, such as c-Jun N-terminal kinase (JNK), nuclear factor-κ B and caspase-3, were also investigated in human colorectal adenomas and in normal colorectal mucosal tissues by immunohistochemistry. Immunofluorescence confocal microscopy was used to investigate the consistency of expression of TNF-R1 and phospho-JNK (p-JNK). RESULTS: The serum levels of soluble TNF-R1 (sTNF-R1) in adenoma patients were significantly higher than in the control group (3.67 ± 0.86 ng/mL vs 1.57 ± 0.72 ng/mL, P < 0.001). Receiver operating characteristic analysis revealed the high diagnostic sensitivity of TNF-R1 measurements (AUC was 0.928) for the diagnosis of adenoma, and the best cut-off level of TNF-R1 was 2.08 ng/mL, with a sensitivity of 93.4% and a specificity of 82.4%. There were no significant differences in the serum levels of TNF-α or sTNF-R2 between the two groups. Immunohistochemistry showed high levels of TNF-R1 and p-JNK expression in the epithelial cells of adenomas. Furthermore, a high incidence of co-localization of TNF-R1 and p-JNK was identified in adenoma tissue. CONCLUSION: TNF-R1 may be a promising biomarker of colorectal adenoma, and it may also play an important role in the very early stages of colorectal carcinogenesis.
基金the National Natural Science Foundation of China,No.30671041the National Basic Research Program of China(973 Program),No. 2005CB623902
文摘BACKGROUND: Studies of several animal models of central nervous system diseases have shown that neural progenitor cells (NPCs) can migrate to injured tissues. Stromal cell-derived factor 1 alpha (SDF-la), and its primary physiological receptor CXCR4, have been shown to contribute to this process. OBJECTIVE: To investigate migration efficacy of human NPCs toward a SDF-1α gradient, and the regulatory roles of tumor necrosis factor-α (TNF-α) and interleukin-8 (IL-8) in SDF-1α/CXCR4 axis-induced migration of NPCs. DESIGN, TIME AND SETTING: An in vitro, randomized, controlled, cellular and molecular biology study was performed at the Laboratory of Department of Cell Biology, Medical College of Soochow University between October 2005 and November 2007. MATERIALS: SDF-1α and mouse anti-human CXCR4 fusion antibody were purchased from R&D Systems, USA. TNF-αwas purchased from Biomyx Technology, USA and IL-8 was kindly provided by the Biotechnology Research Institute of Soochow University. METHODS: NPCs isolated from forebrain tissue of 9 to 10-week-old human fetuses were cultured in vitro. The cells were incubated with 0, 20, and 40 ng/mL TNF-α, or 0, 20, and 40 ng/mL IL-8, for 48 hours prior to migration assay. For antibody-blocking experiments, cells were further pretreated with 0, 20, and 40 μg/mL mouse anti-human CXCR4 fusion antibody for 2 hours. Subsequently, the transwell assay and CXCR4 blockade experiments were performed to evaluate migration of human NPCs toward a SDF-1α gradient. Serum-free culture medium without SDF-1α served as the negative control. MAIN OUTCOME MEASURES: The transwell assay was performed to evaluate migration of human NPCs toward a SDF-1α gradient, which was blocked by fusion antibody against CXCR4. In addition, CXCR4 expression in human NPCs stimulated by TNF-α and IL-8 was measured by flow cytometry. RESULTS: Results from the transwell assay demonstrated that SDF-1α was a strong chemoattractant for human NPCs (P 〈 0.01), and 20 ng/mL produced the highest levels of migration. Anti-human CXCR4 fusion antibody significantly blocked the chemotactic effect (P 〈 0.05). Flow cytometry results showed that treatment with TNF-α and IL-8 resulted in increased CXCR4 expression and greater chemotaxis efficiency of NPCs towards SDF-1α(P 〈 0.01). CONCLUSION: These results demonstrated that SDF-la significantly attracted NPCs in vitro, and neutralizing anti-CXCR4 antibody could block part of this chemotactic function. TNF-α and IL-8 increased chemotaxis efficiency of NPCs towards the SDF-1αgradient by upregulating CXCR4 expression in NPCs.
文摘Objective: To investigate membrane tumor necrosis factor receptor 1 protein expression level in decidua and concentration of soluble tumor necrosis factor receptor 1 in serum in women with unexplained early spontaneous abortion, threatened abortion, and compare the levels with healthy pregnant women. Methods: Thirty-seven women with unexplained early spontaneous abortion, 27 women with threatened abortion, and 34 healthy pregnant women undergoing artificial abortion of pregnancy at 6 - 10 weeks of gestation were selected. Decidual samples were collected when women were undergoing artificial abortion, and blood samples were collected at the same time. The level of membrane tumor necrosis factor receptor 1 in decidua was detected by flow cytometer, and the concentration of soluble tumor necrosis factor receptor 1 in sera was measured with an enzyme-linked immunosorbent assay. Results: The percentages of membrane tumor necrosis factor receptor 1 positive decidual cells were 16.42 ± 7.10 Mean ± SD for women with unexplained early spontaneous abortion and 13. 14 ± 6.30 for healthy pregnant women ( P < 0.05). Serum concentration of soluble tumor necrosis factor receptor 1 was significantly higher in women with unexplained early spontaneous abortion than in healthy pregnant women and in women with threatened abortion, and no difference was found between healthy pregnant women and women with threatened abortion. Conclusion: Women with unexplained early spontaneous abortion present significantly higher expression of tumor necrosis factor receptor 1 than healthy pregnant women, suggesting that over-expression of tumor necrosis factor receptor 1 may contribute to the development of early spontaneous abortion.
基金Supported by Instituto de Salud Carlos III and European Structural Funds in SpainEuropean Regional Development Fund,No.PI19/00206.
文摘Hepatitis C virus(HCV)infection is an excellent immunological model for understanding the mechanisms developed by non-cytopathic viruses and tumors to evade the adaptative immune response.The antigen-specific cytotoxic T cell response is essential for keeping HCV under control,but during persistent infection,these cells become exhausted or even deleted.The exhaustion process is progressive and depends on the infection duration and level of antigenemia.During high antigenic load and long duration of infection,T cells become extremely exhausted and ultimately disappear due to apoptosis.The development of exhaustion involves the impairment of positive co-stimulation induced by regulatory cytokines,such as transforming growth factor beta 1.This cytokine downregulates tumor necrosis factor receptor(TNFR)-associated factor 1(TRAF1),the signal transducer of the T cell co-stimulatory molecule TNFR superfamily member 9(known as 4-1BB).This impairment correlates with the low reactivity of T cells and an exhaustion phenotype.Treatment with interleukin-7 in vitro restores TRAF1 expression and rescues T cell effector function.The process of TRAF1 loss and its in vitro recovery is hierarchical,and more affected by severe disease progression.In conclusion,TRAF1 dynamics on T cells define a new pathogenic model that describes some aspects of the natural history of HCV,and sheds light on novel immunotherapy strategies for chronic viral infections and cancer.
基金Supported by the Swiss National Science Foundation,No.P2SKP3_158649,No.P3400PB_171581,and No.P3P3PB_171582(to Bluemel S)NIH grants(in part),No.R01 AA24726,No.U01 AA026939,and services provided by P30 DK120515(to Schnabl B).
文摘BACKGROUND End-stage liver disease caused by non-alcoholic steatohepatitis(NASH)is the second leading indication for liver transplantation.To date,only moderately effective pharmacotherapies exist to treat NASH.Understanding the pathogenesis of NASH is therefore crucial for the development of new therapies.The inflammatory cytokine tumor necrosis factor alpha(TNF-α)is important for the progression of liver disease.TNF signaling via TNF receptor 1(TNFR1)has been hypothesized to be important for the development of NASH and hepatocellular carcinoma in whole-body knockout animal models.AIM To investigate the role of TNFR1 signaling in hepatocytes for steatohepatitis development in a mouse model of diet-induced NASH.METHODS NASH was induced by a western-style fast-food diet in mice deficient for TNFR1 in hepatocytes(TNFR1ΔHEP)and their wild-type littermates(TNFR1fl/fl).Glucose tolerance was assessed after 18 wk and insulin resistance after 19 wk of feeding.After 20 wk mice were assessed for features of NASH and the metabolic syndrome such as liver weight,liver steatosis,liver fibrosis and markers of liver inflammation.RESULTS Obesity,liver injury,inflammation,steatosis and fibrosis was not different between TNFR1ΔHEP and TNFR1fl/fl mice.However,Tnfr1 deficiency in hepatocytes protected against glucose intolerance and insulin resistance.CONCLUSION Our results indicate that deficiency of TNFR1 signaling in hepatocytes does not protect from diet-induced NASH.However,improved insulin resistance in this model strengthens the role of the liver in glucose homeostasis.
文摘The course and severity of periodontitis can be significantly affected by bacterial virulence as well as host immunity dysfunction. Periodontal tissue destruction has been proved to result from cascade of cytokines synthesized by reactive cells upon stimulation by pathogenic bacteria and lipopolysaccharides within their cell membranes. The clinical use of genetically programmed cells, producing substances blocking IL-1, based on recombinant IL-1 antagonist, as well as cytokines activating fibroblasts and osteoblasts to regenerate the destroyed periodontal tissue could prove alternative to the conventional treatment. Another cytokine of interest in respect to periodontitis ethiopathogenesis is soluble tumor necrosis factor receptor I (sTNF RI). Observation of soluble TNF receptors as physiologic inhibitors of TNF led to its administration in therapeutic process as well as in therapy selected cases of aggressive periodontitis.