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: Tuberculosis (TB) is one of the world’s deadliest infectious diseases. Tumor necrosis factor-Alpha (TNF-α) and Interleukin 8 (IL-8) are involved in the pathogenesis of pulmonary TB (PTB). However, the co...Background: Tuberculosis (TB) is one of the world’s deadliest infectious diseases. Tumor necrosis factor-Alpha (TNF-α) and Interleukin 8 (IL-8) are involved in the pathogenesis of pulmonary TB (PTB). However, the contribution of polymorphisms of these cytokines to PTB susceptibility needed more investigation across geographic regions and ethnic groups. Purpose: The aim of this study was to investigate the association of the TNF-α-308 G/A and IL-8-251T/A polymorphisms with PTB risk in the Congolese population. Methods: This case-control study included 150 PTB patients and 160 control subjects. Blood samples were collected from all participants and were used for the TNF-α-308 G/A and IL-8-251T/A genotyping by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Odds ratios (OR) were calculated to estimate the potential polymorphism associations. A P level of Results: A significant difference was found between PTB patients and controls regarding the TNF-α-308AA genotype (P = 0.035) distribution. Moreover, this genotype was associated with risk to TB (OR = 7.19, 95% CI = 0.85 - 60.65, P = 0.035). The A allele was significantly more frequent in PTB patients than in controls, and was associated with risk to PTB (OR = 1.68, 95% CI = 1.05 - 2.68, P = 0.014). Regarding the IL-8-251T/A gene, TA and AA genotypes were significantly more frequent in PTB patients compared to controls, and were associated with increased risk to PTB (OR = 2.64, 95% CI = 0.97 - 7.18, P = 0.031 and OR = 3.0, 95% CI = 1.13 - 7.98, P = 0.014, respectively). However, the IL-8-251 A allele was not associated to PTB susceptibility (OR = 0.27, 95% CI = 0.15 - 0.44). Conclusion: TNF-α-308G/A and IL-8-251T/A polymorphisms may be associated to PTB susceptibility in the Congolese population, and the AA genotype of both cytokines could be a risk factor.展开更多
BACKGROUND: Pulmonary complications after orthoto- pic liver transplantation (OLT) include high morbidity and mortality. Experimental data have suggested hepatic ische- mia and reperfusion are induced by pro-inflammat...BACKGROUND: Pulmonary complications after orthoto- pic liver transplantation (OLT) include high morbidity and mortality. Experimental data have suggested hepatic ische- mia and reperfusion are induced by pro-inflammatory cyto- kines. The high level of inflammatory cytokines might ad- ditionally influence pulmonary cappillary fluid filtration. The objectives of this study were to measure the concentra- tions of tumor necrotic factor-alpha (TNF-α), interleukin- 6 (IL-6) and interleukin-8 (IL-8) during OLT and to in- vestigate the relationship between these cytokines and post- operative pulmonary complications. METHODS: Twenty-two patients undergoing OLT were divided into two groups according to whether they had postoperative pulmonary complications: group A consis- ting of 8 patients with postoperative pulmonary complica- tions , and group B consisting of 14 patients without post- operative pulmonary complications. Enzyme-linked im- munoassay (ELISA) was used to determine serum TNF-α, IL-6 and IL-8. Blood samples were taken at the beginning of operation (T0 ), clamping and cross-clamping of the in- ferior cava and portal vein (T1, T2 ), 90 minutes and 3 hours after reperfusion (T3 , T4 ) and 24 hours after opera- tion (T5). RESULTS: The level of PaO2/FiO2 in group A was lower than that in group B ( P <0. 05 ). The concentrations of TNF-α, IL-6 and IL-8 in the two groups increased rapidly at T2 , peaked at T3 , decreased rapidly after T3 until 24 hours after operation. The concentrations of TNF-α, IL-6 and IL-8 in group A were higher than those in group B at T2, T3, and T4(P<0.05). CONCLUSION: After un-clamping of the inferior cava and portal vein, the serum concentrations of TNF-α, IL-6 and IL-8 increased may be related to pulmonary injury after he- patic ischemic reperfusion.展开更多
BACKGROUND: With the development of hepatic surgery, especially liver transplantation, the pathophysiological processes of hepatic ischemia-reperfusion (I/R) injury have gained special attention. Controlling I/R injur...BACKGROUND: With the development of hepatic surgery, especially liver transplantation, the pathophysiological processes of hepatic ischemia-reperfusion (I/R) injury have gained special attention. Controlling I/R injury has become one of the most important factors for successful liver transplantation. This study aimed to investigate the effects of tumor necrosis factor-alpha (TNF-alpha) in rats with hepatic I/R injury and promote the recognition of I/R injury in the liver. METHODS: Thirty-two Sprague-Dawley rats were randomly divided into 2 groups. Rats in the sham-operated (SO) group served as controls. Rats in the hepatic ischemia-reperfusion (I/R) group underwent reperfusion after 30 minutes of liver ischemia. Rats were sacrificed at 1, 6 and 12 hours. The expression of TNF-alpha mRNA in the liver was measured by RT-PCR. Histological changes in the liver were assessed. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum were measured. RESULTS: The expression of TNF-alpha mRNA in the SO group was decreased compared with that in the I/R group (P<0.05). TNF-a mRNA expression progressively increased in the I/R group. The serum levels of ALT and AST in the I/R group were higher than those in the SO group (P<0.01). The histological changes were in accord with hepatic I/R injury. CONCLUSION: ALT and AST in serum are closely related to hepatic I/R injury and inflammatory reaction. TNF-alpha production in the liver triggers hepatic I/R injury through a cascade.展开更多
The inhibitory effect of niacinamide on tumor necrosis factor-α （TNF-α） induced annulus fibrous （AF） degradation was assessed, and the mechanism of the inhibition was investigated. Chiba＇s intervertebral disc ...The inhibitory effect of niacinamide on tumor necrosis factor-α （TNF-α） induced annulus fibrous （AF） degradation was assessed, and the mechanism of the inhibition was investigated. Chiba＇s intervertebral disc （IVD） culture model was established. Forty-eight IVDs from 12 adult Japanese white rabbits were randomly divided into 4 groups （12 IVDs in each group）, and various concentrations of niacinamide and TNF-α were added to the medium for intervention： negative control group, niacinamide control group （0.5 mg/mL niacinamide）, degeneration group （10 ng/mL TNF-α）, and treatment group （0.5 mg/mL niacinamide and 10 ng/mL TNF-α）. After one week＇s culture, AFs were collected for glycosaminoglycan （GS） content measurement, safranin O-fast green staining, and immunohistochemical staining for type Ⅰ , Ⅱ collagen and cysteine containing aspartate specific prote- ase-3 （Caspase-3）. It was found that the GS content in treatment group was increased by about 48% as compared with degeneration group （t=16.93, P〈0.001）, and close to that in niacinamide control group （t=0.71, P=0.667）. Safranine O-fast green staining exhibited higher staining density and better histological structure of AF in the treatment group as compared with the degeneration group. Immunohistochemical staining for both TypeⅠ and Ⅱ collagen demonstrated that lamellar structure and continuity of collagen in treatment group were better reserved than in degeneration group. Positive staining rate of Caspase-3 in AFs of negative control group, niacinamide control group, degeneration group and treatment group was 3.4%, 4.3%, 17.9% and 10.3% respectively. The positive rate in treatment group was significantly lower than in degeneration group （P〈0.01）. It was concluded that niacinamide could effectively alleviate TNF-α induced destruction and synthesis inhibition of matrix ingredients in AFs. The inhibition may be related with reduction of expression of Caspase-3. Thus, niacinamide is of potential for IVD degeneration clinical treatment.展开更多
AIM： To investigate the role of tumor necrosis factoralpha （TNF-α） in zebrafish retinal development and myelination. METHODS： Morpholino oligonucleotides （MO）, which are complementary to the translation start...AIM： To investigate the role of tumor necrosis factoralpha （TNF-α） in zebrafish retinal development and myelination. METHODS： Morpholino oligonucleotides （MO）, which are complementary to the translation start site of the wild-type embryonic zebrafish TNF-α mRNA sequence, were synthesized and injected into one to four-cell embryos. The translation blocking specificity was verified by Western blotting using an anti-TNF-α antibody, whole-mount in sltuhybridization using a hepatocytespecific mRNA probe ceruloplasmin （cp）, and coinjection of TNF-α MO and TNF-α mRNA. An atonel homolog 7 （atoh7） mRNA probe was used to detect neurogenesis onset. The retinal neurodifferentiation was analyzed by immunohistochemistry using antibodies Zn12, Zprl, and Zpr3 to label ganglion cells, cones, and rods, respectively. Myelin basic protein （mbp）was used as a marker to track and observe the myelination using whole-mount in situ hybridization. RESULTS： Targeted knockdown of TNF-α resulted in specific suppression of TNF-α expression and a severely underdeveloped liver. The co-injection of TNF-α MO and mRNA rescued the liver development. Retinal neurogenesis in TNF-cc morphants was initiated on time. The retina was fully laminated, while ganglion cells, cones, and rods were well differentiated at 72 hours post-fertilization （hpf）. mbp was expressed in Schwann cells in the lateral line nerves and cranial nerves from 3 days post -fertilization （dpf） as well as in oligodendrocytes linearly along the hindbrain bundles and the spinal cord from 4 dpf, which closely resembled its endogenous profile. CONCLUSION： TNF-α is not an essential regulator for retinal neurogenesis and optic myelination.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
Ulcerative jejunoileitis is an uncommon clinical syndrome consisting of abdominal pain,weight loss associated with diarrhea,and multiple inflammatory ulcerations and strictures of the small bowel.Ulcerative jejunoilei...Ulcerative jejunoileitis is an uncommon clinical syndrome consisting of abdominal pain,weight loss associated with diarrhea,and multiple inflammatory ulcerations and strictures of the small bowel.Ulcerative jejunoileitis can complicate established celiac disease or develop in patients de novo.Increased levels of tumor necrosis factor-alpha(TNF-α) in the small intestine of patients with untreated celiac disease are associated with a role in the immune pathogenesis of this disorder.No specific therapy has been shown to change the course of ulcerative jejunoileitis.We report a case of severe ulcerative jejunoileitis previously unresponsive to traditional therapies,including high dose corticosteroids and cyclosporine.The patient had a dramatic resolution of symptoms and a complete normalization of endoscopic findings after anti-TNF-α monoclonal antibody,infliximab(Remicade).展开更多
AIM:To study the expression of tumor necrosis factor- alpha converting enzyme (TACE) and evaluate its significance in liver regeneration after partial hepatectomy in vivo. METHODS: Male SD rats underwent 70% partial h...AIM:To study the expression of tumor necrosis factor- alpha converting enzyme (TACE) and evaluate its significance in liver regeneration after partial hepatectomy in vivo. METHODS: Male SD rats underwent 70% partial hepatec- tomy. The remaining liver and spleen tissue samples were collected at indicated time points after hepatectomy. TACE expression was investigated by Western blotting, immunohistochemistry, and serial section immunostaining. RESULTS: Expression of TACE in liver and spleen tissues after partial hepatectomy was a time-dependent alteration, reaching a maximal level between 24 and 48 h and remaining elevated for more than 168 h. TACE protein was localized to mononuclear cells (MNC), which infiltrated the liver from the spleen after hepatectomy. The kinetics of TACE expression was in accordance with the number of TACE-staining MNCs and synchronized with those of transforming growth factor-α (TGFα). In addition, TACE-staining MNC partially overlapped with CD3+ T lymphocytes. CONCLUSION: TACE may be involved in liver regenera- tion by pathway mediated with TGFα-EGFR in the cell- cycle progressive phase in vivo. TACE production and effect by paracrine may be a pathway of involvement in liver regeneration for the activated CD3+ T lymphocytes.展开更多
Low survival rate occurs in patients who initially experience a spontaneous return of circulation after cardiac arrest（CA）. In this study, we induced asphyxial CA in adult male Sprague-Daley rats, maintained their b...Low survival rate occurs in patients who initially experience a spontaneous return of circulation after cardiac arrest（CA）. In this study, we induced asphyxial CA in adult male Sprague-Daley rats, maintained their body temperature at 37 ± 0.5°C, and then observed the survival rate during the post-resuscitation phase. We examined neuronal damage in the hippocampus using cresyl violet（CV） and Fluore-Jade B（F-J B） staining, and pro-inflammatory response using ionized calcium-binding adapter molecule 1（Iba-1）, glial fibrillary acidic protein（GFAP）, and tumor necrosis factor-alpha（TNF-α） immunohistochemistry in the hippocampus after asphyxial CA in rats under normothermia. Our results show that the survival rate decreased gradually post-CA（about 63% at 6 hours, 37% at 1 day, and 8% at 2 days post-CA）. Rats were sacrificed at these points in time post-CA, and no neuronal damage was found in the hippocampus until 1 day post-CA. However, some neurons in the stratum pyramidale of the CA region in the hippocampus were dead 2 days post-CA. Iba-1 immunoreactive microglia in the CA1 region did not change until 1 day postCA, and they were activated（enlarged cell bodies with short and thicken processes） in all layers 2 days postCA. Meanwhile, GFAP-immunoreactive astrocytes did not change significantly until 2 days post-CA. TNF-α immunoreactivity decreased significantly in neurons of the stratum pyramidale in the CA1 region 6 hours post-CA, decreased gradually until 1 day post-CA, and increased significantly again 2 days post-CA. These findings suggest that low survival rate of normothermic rats in the early period of asphyxia-induced CA is related to increased TNF-α immunoreactivity, but not to neuronal damage in the hippocampal CA1 region.展开更多
As an aquatic fish,the spotted halibut Verasper variegatus is highly susceptible to bacterial and virus infections.Tumor necrosis factor-alpha(TNF-α)as a cytokine could control the inflammatory responses.The function...As an aquatic fish,the spotted halibut Verasper variegatus is highly susceptible to bacterial and virus infections.Tumor necrosis factor-alpha(TNF-α)as a cytokine could control the inflammatory responses.The functions of TNF-αin many species have been widely studied,particularly in mammals.However,little is known about the TNF-αfunctions in V.variegatus.We first cloned and sequenced the TNF-αgene in V.variegatus(VvTNF-α).The two conserved cysteine residues,transmembrane sequence,Thr-Leu motif,and TNF family signature,as well as the TA-rich motifs of its proteins related to inflammatory responses had high similarity to those of the other teleost and mammalian TNF-α.The phylogenetic analysis showed that VvTNF-αwas consistent with TNF-αgenes of other vertebrates.The VvTNF-αtranscripts were extensively distributed in the peripheral blood leukocytes(PBLs),spleen,and gill,indicating that the VvTNF-αhad a role in immune function.Furthermore,treatment with pathogen-associated molecular patterns(PAMPs)could induce a rapid and significant increase of VvTNF-αin the PBLs,which reveals that VvTNF-αdoes participate in the host immune responses against bacterial and viral pathogens.We found that VvTNF-αhad an interesting expression pattern during metamorphosis,showing that the flatfish TNF-αmay have some novel functions during specific developmental stages.In addition,the 3 D structure prediction of VvTNF-αprovided an indication of how it is likely to interact with other proteins.Therefore,VvTNF-αhas multiple functions,and provides valuable information to explore novel functions of TNF-α.展开更多
BACKGROUND： Cerebral infarction is poorly treated due to neuronal necrosis and secondary pathophysiological changes; for example, free radical production and inflammatory reactions. OBJECTIVE： To detect the levels o...BACKGROUND： Cerebral infarction is poorly treated due to neuronal necrosis and secondary pathophysiological changes; for example, free radical production and inflammatory reactions. OBJECTIVE： To detect the levels of high-sensitivity C-reactive protein （hs-CRP）, interleukin-6 （IL-6）, and tumor necrosis factor- a （TNF- α ） in elderly males with cerebral infarction. DESIGN： Non-randomized current control study. SETTING： Cadre Medical Department, Guizhou Provincial People＇s Hospital. PARTICIPANTS： Forty elderly males （65-89 years old） with cerebral infarction were selected from Cadre Medical Department, Guizhou Provincial People＇s Hospital from February 2004 to December 2006. All patients met the diagnostic criteria of cerebral infarction modified at the 4th National Cerebrovascular Disease Academic Meeting, and were diagnosed on the basis of CT or MRI tests. Furthermore, 35 elderly male inpatients （65-87 years old） without cerebral infarction were selected as the control group. Included subjects provided confirmed consent and did not have heart disease, diabetes mellitus, lipid disorder, acute trauma, infection, rheumatism, or other inflammatory diseases. The study was approved by the local ethics committee. There were no significant differences in age, blood pressure, and lipid levels between the cerebral infarction group and the control group （P 〉 0.05）, and this suggested that the baseline data of both groups were comparable. METHODS： Fasting venous blood was drawn from cerebral infarction patients 24 hours after cerebral infarction attack and from control subjects 24 hours after hospitalization. A latex-enhanced immunoturbidimetric assay and an enzyme-linked immunosorbent assay were used to detect the levels of hs-CRP, IL-6, and TNF- α in the serum. MAIN OUTCOME MEASURES： The levels of hs-CRP, 1L-6, and TNF- α in the serum in both groups. RESULTS： Forty cerebral infarction patients and thirty-five control subjects were included in the final analysis without any loss. Levels of hs-CRP, IL-6, and TNF-α in the cerebral infarction group were significantly higher than those in the control group （P 〈 0.01 ）. CONCLUSION： Levels of serum inflammatory reactive factors are increased in elderly males with cerebral infarction.展开更多
Tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) are involved in the progression of coronary artery disease (CAD). The cytokines’ levels are associated with the severity of CAD. We have recently repor...Tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) are involved in the progression of coronary artery disease (CAD). The cytokines’ levels are associated with the severity of CAD. We have recently reported on the association of resistin, a relatively novel cytokine with the pathogenesis of cardiovascular disease (CVD). Although the inflammatory cytokines’ impact on atherosclerosis is widely accepted, yet some controversy exists regarding the involvement of these factors in atherogenesis. The current review highlights the potential association of TNF-alpha, IL-6 and resistin SNPs (single nucleotide polymorphisms) with CAD. Molecular genetics data along with the intracellular signaling cascade mechanisms may have important clinical implications in the treatment of CAD.展开更多
TNF-α was found originally In sera of Bacillus Calmette Guerln infected mice as a macrophage derived factor. It Is cytotoxlc for tumor cell and less or not toxic to normal cells in vitor. The gene for human TNF-α wi...TNF-α was found originally In sera of Bacillus Calmette Guerln infected mice as a macrophage derived factor. It Is cytotoxlc for tumor cell and less or not toxic to normal cells in vitor. The gene for human TNF-α with E. coli-preferred codons has been designed according to the amino acid sequence deduced from the cDNA. The gene with 504 bp was divided into 27 oligonucleotide fragments having 30. to 40 nucleotides each. The solid phase phosphotriester method was used for the synthesis of these oligonucleotides. The 27 fragments were annealed to three segments and then linked by T4 DNA ligase. The entire gene was incorporated into plasmld PDR540 with Tac promoter which was used to transform E. coli 7118. The expressed protein was estimated by SDSPAGE with a molecular weight of 1. 7×104Da. The cytotoxlc activity of the product against L-929 cell was 1. 0×107units/ml culture.展开更多
Reactive astrogliosis has been implicated in the failure of axonal regeneration in adult mammalian Central Nervous System (CNS). It is our hypothesis that inflammatory cytokines act upon astrocytes to alter their bioc...Reactive astrogliosis has been implicated in the failure of axonal regeneration in adult mammalian Central Nervous System (CNS). It is our hypothesis that inflammatory cytokines act upon astrocytes to alter their biochemical and physical properties, which may in turn be responsible for the failure of neuronal regeneration. We have therefore examined the effect of tumor-necrosis factor-alpha (TNF-α) on the ability of astrocytes to support the survival of the cortical neurons and the growth of the neurites. Mouse astrocytes and cortical neuronal cultures were prepared. It was observed that when neurons were cultured in absence of astrocytes only a few of them grew and survived only for 5-6 days. These neurons had small cell bodies and few, short neurites. However, when the same numbers of neurons were cultured on the top of astrocytes, more neurons grew and survived up to 16-18 days. They had bigger cell bodies and many long branched neurites that formed anestamosing networks. The neurons then coalesced and the neurites formed thick bundles. When the same numbers of neurons were grown on the top of astrocytes pre-treated with TNF-α, few neurons survived up to 13 days. The neurites of the survived neurons were shorter than neurites of neurons grown on normal astrocytes and did not form bundles. In addition, TNF-α stimulated the expression of glial fibrillary acidic protein (GFAP) by astrocytes. These results support that the pro-inflammatory cytokine, TNF-α modulates the gliosis and that the astrocytic cell supports neuronal survival and neurite outgrowth.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
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.
文摘Background: Tuberculosis (TB) is one of the world’s deadliest infectious diseases. Tumor necrosis factor-Alpha (TNF-α) and Interleukin 8 (IL-8) are involved in the pathogenesis of pulmonary TB (PTB). However, the contribution of polymorphisms of these cytokines to PTB susceptibility needed more investigation across geographic regions and ethnic groups. Purpose: The aim of this study was to investigate the association of the TNF-α-308 G/A and IL-8-251T/A polymorphisms with PTB risk in the Congolese population. Methods: This case-control study included 150 PTB patients and 160 control subjects. Blood samples were collected from all participants and were used for the TNF-α-308 G/A and IL-8-251T/A genotyping by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Odds ratios (OR) were calculated to estimate the potential polymorphism associations. A P level of Results: A significant difference was found between PTB patients and controls regarding the TNF-α-308AA genotype (P = 0.035) distribution. Moreover, this genotype was associated with risk to TB (OR = 7.19, 95% CI = 0.85 - 60.65, P = 0.035). The A allele was significantly more frequent in PTB patients than in controls, and was associated with risk to PTB (OR = 1.68, 95% CI = 1.05 - 2.68, P = 0.014). Regarding the IL-8-251T/A gene, TA and AA genotypes were significantly more frequent in PTB patients compared to controls, and were associated with increased risk to PTB (OR = 2.64, 95% CI = 0.97 - 7.18, P = 0.031 and OR = 3.0, 95% CI = 1.13 - 7.98, P = 0.014, respectively). However, the IL-8-251 A allele was not associated to PTB susceptibility (OR = 0.27, 95% CI = 0.15 - 0.44). Conclusion: TNF-α-308G/A and IL-8-251T/A polymorphisms may be associated to PTB susceptibility in the Congolese population, and the AA genotype of both cytokines could be a risk factor.
文摘BACKGROUND: Pulmonary complications after orthoto- pic liver transplantation (OLT) include high morbidity and mortality. Experimental data have suggested hepatic ische- mia and reperfusion are induced by pro-inflammatory cyto- kines. The high level of inflammatory cytokines might ad- ditionally influence pulmonary cappillary fluid filtration. The objectives of this study were to measure the concentra- tions of tumor necrotic factor-alpha (TNF-α), interleukin- 6 (IL-6) and interleukin-8 (IL-8) during OLT and to in- vestigate the relationship between these cytokines and post- operative pulmonary complications. METHODS: Twenty-two patients undergoing OLT were divided into two groups according to whether they had postoperative pulmonary complications: group A consis- ting of 8 patients with postoperative pulmonary complica- tions , and group B consisting of 14 patients without post- operative pulmonary complications. Enzyme-linked im- munoassay (ELISA) was used to determine serum TNF-α, IL-6 and IL-8. Blood samples were taken at the beginning of operation (T0 ), clamping and cross-clamping of the in- ferior cava and portal vein (T1, T2 ), 90 minutes and 3 hours after reperfusion (T3 , T4 ) and 24 hours after opera- tion (T5). RESULTS: The level of PaO2/FiO2 in group A was lower than that in group B ( P <0. 05 ). The concentrations of TNF-α, IL-6 and IL-8 in the two groups increased rapidly at T2 , peaked at T3 , decreased rapidly after T3 until 24 hours after operation. The concentrations of TNF-α, IL-6 and IL-8 in group A were higher than those in group B at T2, T3, and T4(P<0.05). CONCLUSION: After un-clamping of the inferior cava and portal vein, the serum concentrations of TNF-α, IL-6 and IL-8 increased may be related to pulmonary injury after he- patic ischemic reperfusion.
文摘BACKGROUND: With the development of hepatic surgery, especially liver transplantation, the pathophysiological processes of hepatic ischemia-reperfusion (I/R) injury have gained special attention. Controlling I/R injury has become one of the most important factors for successful liver transplantation. This study aimed to investigate the effects of tumor necrosis factor-alpha (TNF-alpha) in rats with hepatic I/R injury and promote the recognition of I/R injury in the liver. METHODS: Thirty-two Sprague-Dawley rats were randomly divided into 2 groups. Rats in the sham-operated (SO) group served as controls. Rats in the hepatic ischemia-reperfusion (I/R) group underwent reperfusion after 30 minutes of liver ischemia. Rats were sacrificed at 1, 6 and 12 hours. The expression of TNF-alpha mRNA in the liver was measured by RT-PCR. Histological changes in the liver were assessed. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum were measured. RESULTS: The expression of TNF-alpha mRNA in the SO group was decreased compared with that in the I/R group (P<0.05). TNF-a mRNA expression progressively increased in the I/R group. The serum levels of ALT and AST in the I/R group were higher than those in the SO group (P<0.01). The histological changes were in accord with hepatic I/R injury. CONCLUSION: ALT and AST in serum are closely related to hepatic I/R injury and inflammatory reaction. TNF-alpha production in the liver triggers hepatic I/R injury through a cascade.
文摘The inhibitory effect of niacinamide on tumor necrosis factor-α （TNF-α） induced annulus fibrous （AF） degradation was assessed, and the mechanism of the inhibition was investigated. Chiba＇s intervertebral disc （IVD） culture model was established. Forty-eight IVDs from 12 adult Japanese white rabbits were randomly divided into 4 groups （12 IVDs in each group）, and various concentrations of niacinamide and TNF-α were added to the medium for intervention： negative control group, niacinamide control group （0.5 mg/mL niacinamide）, degeneration group （10 ng/mL TNF-α）, and treatment group （0.5 mg/mL niacinamide and 10 ng/mL TNF-α）. After one week＇s culture, AFs were collected for glycosaminoglycan （GS） content measurement, safranin O-fast green staining, and immunohistochemical staining for type Ⅰ , Ⅱ collagen and cysteine containing aspartate specific prote- ase-3 （Caspase-3）. It was found that the GS content in treatment group was increased by about 48% as compared with degeneration group （t=16.93, P〈0.001）, and close to that in niacinamide control group （t=0.71, P=0.667）. Safranine O-fast green staining exhibited higher staining density and better histological structure of AF in the treatment group as compared with the degeneration group. Immunohistochemical staining for both TypeⅠ and Ⅱ collagen demonstrated that lamellar structure and continuity of collagen in treatment group were better reserved than in degeneration group. Positive staining rate of Caspase-3 in AFs of negative control group, niacinamide control group, degeneration group and treatment group was 3.4%, 4.3%, 17.9% and 10.3% respectively. The positive rate in treatment group was significantly lower than in degeneration group （P〈0.01）. It was concluded that niacinamide could effectively alleviate TNF-α induced destruction and synthesis inhibition of matrix ingredients in AFs. The inhibition may be related with reduction of expression of Caspase-3. Thus, niacinamide is of potential for IVD degeneration clinical treatment.
基金Supported by the National Natural Science Foundation of China (No.81301080)the Tianjin Natural Science Foundation (No.15JCYBJC24400, No.15JCQNJC10900)the Scientific Research Foundation for the Returned Overseas Chinese Scholars (No.2012-1707)
文摘AIM： To investigate the role of tumor necrosis factoralpha （TNF-α） in zebrafish retinal development and myelination. METHODS： Morpholino oligonucleotides （MO）, which are complementary to the translation start site of the wild-type embryonic zebrafish TNF-α mRNA sequence, were synthesized and injected into one to four-cell embryos. The translation blocking specificity was verified by Western blotting using an anti-TNF-α antibody, whole-mount in sltuhybridization using a hepatocytespecific mRNA probe ceruloplasmin （cp）, and coinjection of TNF-α MO and TNF-α mRNA. An atonel homolog 7 （atoh7） mRNA probe was used to detect neurogenesis onset. The retinal neurodifferentiation was analyzed by immunohistochemistry using antibodies Zn12, Zprl, and Zpr3 to label ganglion cells, cones, and rods, respectively. Myelin basic protein （mbp）was used as a marker to track and observe the myelination using whole-mount in situ hybridization. RESULTS： Targeted knockdown of TNF-α resulted in specific suppression of TNF-α expression and a severely underdeveloped liver. The co-injection of TNF-α MO and mRNA rescued the liver development. Retinal neurogenesis in TNF-cc morphants was initiated on time. The retina was fully laminated, while ganglion cells, cones, and rods were well differentiated at 72 hours post-fertilization （hpf）. mbp was expressed in Schwann cells in the lateral line nerves and cranial nerves from 3 days post -fertilization （dpf） as well as in oligodendrocytes linearly along the hindbrain bundles and the spinal cord from 4 dpf, which closely resembled its endogenous profile. CONCLUSION： TNF-α is not an essential regulator for retinal neurogenesis and optic myelination.
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.
文摘Ulcerative jejunoileitis is an uncommon clinical syndrome consisting of abdominal pain,weight loss associated with diarrhea,and multiple inflammatory ulcerations and strictures of the small bowel.Ulcerative jejunoileitis can complicate established celiac disease or develop in patients de novo.Increased levels of tumor necrosis factor-alpha(TNF-α) in the small intestine of patients with untreated celiac disease are associated with a role in the immune pathogenesis of this disorder.No specific therapy has been shown to change the course of ulcerative jejunoileitis.We report a case of severe ulcerative jejunoileitis previously unresponsive to traditional therapies,including high dose corticosteroids and cyclosporine.The patient had a dramatic resolution of symptoms and a complete normalization of endoscopic findings after anti-TNF-α monoclonal antibody,infliximab(Remicade).
文摘AIM:To study the expression of tumor necrosis factor- alpha converting enzyme (TACE) and evaluate its significance in liver regeneration after partial hepatectomy in vivo. METHODS: Male SD rats underwent 70% partial hepatec- tomy. The remaining liver and spleen tissue samples were collected at indicated time points after hepatectomy. TACE expression was investigated by Western blotting, immunohistochemistry, and serial section immunostaining. RESULTS: Expression of TACE in liver and spleen tissues after partial hepatectomy was a time-dependent alteration, reaching a maximal level between 24 and 48 h and remaining elevated for more than 168 h. TACE protein was localized to mononuclear cells (MNC), which infiltrated the liver from the spleen after hepatectomy. The kinetics of TACE expression was in accordance with the number of TACE-staining MNCs and synchronized with those of transforming growth factor-α (TGFα). In addition, TACE-staining MNC partially overlapped with CD3+ T lymphocytes. CONCLUSION: TACE may be involved in liver regenera- tion by pathway mediated with TGFα-EGFR in the cell- cycle progressive phase in vivo. TACE production and effect by paracrine may be a pathway of involvement in liver regeneration for the activated CD3+ T lymphocytes.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)the Ministry of Education(NRF-2014R1A1A2057263)+2 种基金by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT&Future Planning(NRF-2017R1A2B4009079&NRF-2017R1A2B4008403)by the Bio-Synergy Research Project(NRF-2015M3A9C4076322)of the Ministry of ScienceICT and Future Planning through the National Research Foundation
文摘Low survival rate occurs in patients who initially experience a spontaneous return of circulation after cardiac arrest（CA）. In this study, we induced asphyxial CA in adult male Sprague-Daley rats, maintained their body temperature at 37 ± 0.5°C, and then observed the survival rate during the post-resuscitation phase. We examined neuronal damage in the hippocampus using cresyl violet（CV） and Fluore-Jade B（F-J B） staining, and pro-inflammatory response using ionized calcium-binding adapter molecule 1（Iba-1）, glial fibrillary acidic protein（GFAP）, and tumor necrosis factor-alpha（TNF-α） immunohistochemistry in the hippocampus after asphyxial CA in rats under normothermia. Our results show that the survival rate decreased gradually post-CA（about 63% at 6 hours, 37% at 1 day, and 8% at 2 days post-CA）. Rats were sacrificed at these points in time post-CA, and no neuronal damage was found in the hippocampus until 1 day post-CA. However, some neurons in the stratum pyramidale of the CA region in the hippocampus were dead 2 days post-CA. Iba-1 immunoreactive microglia in the CA1 region did not change until 1 day postCA, and they were activated（enlarged cell bodies with short and thicken processes） in all layers 2 days postCA. Meanwhile, GFAP-immunoreactive astrocytes did not change significantly until 2 days post-CA. TNF-α immunoreactivity decreased significantly in neurons of the stratum pyramidale in the CA1 region 6 hours post-CA, decreased gradually until 1 day post-CA, and increased significantly again 2 days post-CA. These findings suggest that low survival rate of normothermic rats in the early period of asphyxia-induced CA is related to increased TNF-α immunoreactivity, but not to neuronal damage in the hippocampal CA1 region.
基金Supported by the National High Technology Research and Development Program of China(863 Program)(No.31101891)the Hitech Research and Development Program of China(No.2012AA10A408)
文摘As an aquatic fish,the spotted halibut Verasper variegatus is highly susceptible to bacterial and virus infections.Tumor necrosis factor-alpha(TNF-α)as a cytokine could control the inflammatory responses.The functions of TNF-αin many species have been widely studied,particularly in mammals.However,little is known about the TNF-αfunctions in V.variegatus.We first cloned and sequenced the TNF-αgene in V.variegatus(VvTNF-α).The two conserved cysteine residues,transmembrane sequence,Thr-Leu motif,and TNF family signature,as well as the TA-rich motifs of its proteins related to inflammatory responses had high similarity to those of the other teleost and mammalian TNF-α.The phylogenetic analysis showed that VvTNF-αwas consistent with TNF-αgenes of other vertebrates.The VvTNF-αtranscripts were extensively distributed in the peripheral blood leukocytes(PBLs),spleen,and gill,indicating that the VvTNF-αhad a role in immune function.Furthermore,treatment with pathogen-associated molecular patterns(PAMPs)could induce a rapid and significant increase of VvTNF-αin the PBLs,which reveals that VvTNF-αdoes participate in the host immune responses against bacterial and viral pathogens.We found that VvTNF-αhad an interesting expression pattern during metamorphosis,showing that the flatfish TNF-αmay have some novel functions during specific developmental stages.In addition,the 3 D structure prediction of VvTNF-αprovided an indication of how it is likely to interact with other proteins.Therefore,VvTNF-αhas multiple functions,and provides valuable information to explore novel functions of TNF-α.
基金Educational and Technological Foundation for Excellent Talents of Guizhou Province, No. 2005(25)
文摘BACKGROUND： Cerebral infarction is poorly treated due to neuronal necrosis and secondary pathophysiological changes; for example, free radical production and inflammatory reactions. OBJECTIVE： To detect the levels of high-sensitivity C-reactive protein （hs-CRP）, interleukin-6 （IL-6）, and tumor necrosis factor- a （TNF- α ） in elderly males with cerebral infarction. DESIGN： Non-randomized current control study. SETTING： Cadre Medical Department, Guizhou Provincial People＇s Hospital. PARTICIPANTS： Forty elderly males （65-89 years old） with cerebral infarction were selected from Cadre Medical Department, Guizhou Provincial People＇s Hospital from February 2004 to December 2006. All patients met the diagnostic criteria of cerebral infarction modified at the 4th National Cerebrovascular Disease Academic Meeting, and were diagnosed on the basis of CT or MRI tests. Furthermore, 35 elderly male inpatients （65-87 years old） without cerebral infarction were selected as the control group. Included subjects provided confirmed consent and did not have heart disease, diabetes mellitus, lipid disorder, acute trauma, infection, rheumatism, or other inflammatory diseases. The study was approved by the local ethics committee. There were no significant differences in age, blood pressure, and lipid levels between the cerebral infarction group and the control group （P 〉 0.05）, and this suggested that the baseline data of both groups were comparable. METHODS： Fasting venous blood was drawn from cerebral infarction patients 24 hours after cerebral infarction attack and from control subjects 24 hours after hospitalization. A latex-enhanced immunoturbidimetric assay and an enzyme-linked immunosorbent assay were used to detect the levels of hs-CRP, IL-6, and TNF- α in the serum. MAIN OUTCOME MEASURES： The levels of hs-CRP, 1L-6, and TNF- α in the serum in both groups. RESULTS： Forty cerebral infarction patients and thirty-five control subjects were included in the final analysis without any loss. Levels of hs-CRP, IL-6, and TNF-α in the cerebral infarction group were significantly higher than those in the control group （P 〈 0.01 ）. CONCLUSION： Levels of serum inflammatory reactive factors are increased in elderly males with cerebral infarction.
文摘Tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) are involved in the progression of coronary artery disease (CAD). The cytokines’ levels are associated with the severity of CAD. We have recently reported on the association of resistin, a relatively novel cytokine with the pathogenesis of cardiovascular disease (CVD). Although the inflammatory cytokines’ impact on atherosclerosis is widely accepted, yet some controversy exists regarding the involvement of these factors in atherogenesis. The current review highlights the potential association of TNF-alpha, IL-6 and resistin SNPs (single nucleotide polymorphisms) with CAD. Molecular genetics data along with the intracellular signaling cascade mechanisms may have important clinical implications in the treatment of CAD.
文摘TNF-α was found originally In sera of Bacillus Calmette Guerln infected mice as a macrophage derived factor. It Is cytotoxlc for tumor cell and less or not toxic to normal cells in vitor. The gene for human TNF-α with E. coli-preferred codons has been designed according to the amino acid sequence deduced from the cDNA. The gene with 504 bp was divided into 27 oligonucleotide fragments having 30. to 40 nucleotides each. The solid phase phosphotriester method was used for the synthesis of these oligonucleotides. The 27 fragments were annealed to three segments and then linked by T4 DNA ligase. The entire gene was incorporated into plasmld PDR540 with Tac promoter which was used to transform E. coli 7118. The expressed protein was estimated by SDSPAGE with a molecular weight of 1. 7×104Da. The cytotoxlc activity of the product against L-929 cell was 1. 0×107units/ml culture.
文摘Reactive astrogliosis has been implicated in the failure of axonal regeneration in adult mammalian Central Nervous System (CNS). It is our hypothesis that inflammatory cytokines act upon astrocytes to alter their biochemical and physical properties, which may in turn be responsible for the failure of neuronal regeneration. We have therefore examined the effect of tumor-necrosis factor-alpha (TNF-α) on the ability of astrocytes to support the survival of the cortical neurons and the growth of the neurites. Mouse astrocytes and cortical neuronal cultures were prepared. It was observed that when neurons were cultured in absence of astrocytes only a few of them grew and survived only for 5-6 days. These neurons had small cell bodies and few, short neurites. However, when the same numbers of neurons were cultured on the top of astrocytes, more neurons grew and survived up to 16-18 days. They had bigger cell bodies and many long branched neurites that formed anestamosing networks. The neurons then coalesced and the neurites formed thick bundles. When the same numbers of neurons were grown on the top of astrocytes pre-treated with TNF-α, few neurons survived up to 13 days. The neurites of the survived neurons were shorter than neurites of neurons grown on normal astrocytes and did not form bundles. In addition, TNF-α stimulated the expression of glial fibrillary acidic protein (GFAP) by astrocytes. These results support that the pro-inflammatory cytokine, TNF-α modulates the gliosis and that the astrocytic cell supports neuronal survival and neurite outgrowth.
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.
