Interferon-gamma and tumor necrosis factor-alpha synergistically enhance the immunosuppressive capacity of human umbilical-cordderived mesenchymal stem cells by increasing PD-L1 expression

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.

Tumor Necrosis Factor-Alpha (TNF)-308G/A and Interleukin 8(IL-8)-251C/T Polymorphisms in Pulmonary Tuberculosis Patients from Congo

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.

Study of tumor necrosis factor receptor in the inflammatory bowel disease

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.

Anti-tumour necrosis factor agent and liver injury:literature review,recommendations for management

Abnormalities in liver function tests,including transient and self-limiting hypertransaminasemia,cholestatic disease and hepatitis,can develop during treatment with anti-tumour-necrosis-factor(TNF)therapy.The optimal management of liver injury related to antiTNF therapy is still a matter of debate.Although some authors recommend discontinuing treatment in case of both a rise of alanine aminotransferase more than5 times the upper limit of normal,or the occurrence of jaundice,there are no standard guidelines for the management of anti-TNF-related liver injury.Bibliographical searches were performed in Pub Med,using the following key words:inflammatory bowel disease(IBD);TNF inhibitors;hypertransaminasemia;drugrelated liver injury;infliximab.According to published data,elevation of transaminases in patients with IBD treated with anti-TNF is a common finding,but resolution appears to be the usual outcome.Anti-TNF agents seem to be safe with a low risk of causing severe drugrelated liver injury.According to our centre experience,we found that hypertransaminasemia was a common,mainly self-limiting finding in our IBD cohort and was not correlated to infliximab treatment on both univariate and multivariate analyses.An algorithm for the management of liver impairment occurring during antiTNF treatment is also proposed and this highlights the need of a multidisciplinary approach and suggests liver biopsy as a key-point in the management decision in case of severe rise of transaminases.However,hepatic injury is generally self-limiting and drug withdrawal seems to be an exception.

Effect of tumor necrosis factor-alpha in rats with hepatic ischemia-reperfusion injury

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.

Zinc-α2-glycoprotein 1 attenuates non-alcoholic fatty liver disease by negatively regulating tumour necrosis factor-α

BACKGROUND Zinc-α2-glycoprotein 1 (AZGP1) plays important roles in metabolism-related diseases. The underlying molecular mechanisms and therapeutic effects of AZGP1 remain unknown in non-alcoholic fatty liver disease (NAFLD). AIM To explore the effects and potential mechanism of AZGP1 on NAFLD in vivo and in vitro. METHODS The expression of AZGP1 and its effects on hepatocytes were examined in NAFLD patients, CCl4-treated mice fed a high fat diet (HFD), and human LO2 cells. RESULTS AZGP1 levels were significantly decreased in liver tissues of NAFLD patients and mice. AZGP1 knockdown was found to activate inflammation;enhance steatogenesis, including promoting lipogenesis [sterol regulatory elementbinding protein (SREBP)-1c, liver X receptor (LXR), fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), and stearoyl CoA desaturase 1 (SCD)-1], increasing lipid transport and accumulation [fatty acid transport protein (FATP), carnitine palmitoyl transferase (CPT)-1A, and adiponectin], and reducing fatty acid β-oxidation [farnesoid X receptor (FXR) and peroxisome proliferator-activated receptor (PPAR)-α];accelerate proliferation;and reverse apoptosis in LO2 cells. AZGP1 overexpression (OV-AZGP1) had the opposite effects. Furthermore, AZGP1 alleviated NAFLD by blocking TNF-α-mediated inflammation and intracellular lipid deposition, promoting proliferation, and inhibiting apoptosis in LO2 cells. Finally, treatment with OV-AZGP1 plasmid dramatically improved liver injury and eliminated liver fat in NAFLD mice. CONCLUSION AZGP1 attenuates NAFLD with regard to ameliorating inflammation, accelerating lipolysis, promoting proliferation, and reducing apoptosis by negatively regulating TNF-α. AZGP1 is suggested to be a novel promising therapeutic target for NAFLD.

Single nucleotide polymorphism in the tumor necrosis factor-alpha gene affects inflammatory bowel diseases risk

AIM: To investigate the role that single nucleotide polymorphisms (SNPs) in the promoter of the tumour necrosis factor-alpha (TNF-α) gene play in the risk of inflammatory bowel diseases (IBDs) in a New Zealand population, in the context of international studies. METHODS: DNA samples from 388 patients with Crohn's disease (CD), 405 ulcerative colitis (UC), 27 indeterminate colitis (IC) and 201 randomly selected controls, from Canterbury, New Zealand were screened for 3 common polymorphisms in the TNF-α receptor: -238 G→A, -308 G→A and -857C→T, using a TaqmanR assay. A meta-analysis was performed on the data obtained on these polymorphisms combined with that from other published studies. RESULTS: Individuals carrying the -308 G/A allele had a significantly (OR = 1.91, χ2 = 17.36, P < 0.0001) increased risk of pancolitis, and a 1.57-fold increased risk (OR = 1.57, χ2 = 4.34, P = 0.037) of requiring a bowel resection in UC. Carrying the -857 C/T variant decreased the risk of ileocolonic CD (OR = 0.56, χ2 =4.32, P = 0.037), and the need for a bowel resection (OR = 0.59, χ2 = 4.85, P = 0.028). The risk of UC was reduced in individuals who were smokers at diagnosis, (OR = 0.48, χ2 = 4.86, P = 0.028). CONCLUSION: TNF-α is a key cytokine known to play a role in inflammatory response, and the locus for the gene is found in the IBD3 region on chromosome 6p21, known to be associated with an increased risk for IBD. The -308 G/A SNP in the TNF-α promoter is functional, and may account in part for the increased UC risk associated with the IBD3 genomic region. The -857 C/T SNP may decrease IBD risk in certain groups. Pharmaco- or nutrigenomic approaches may be desir- able for individuals with such affected genotypes.

Experimental Study on Inhibitory Effect of Niacinamide on Tumor Necrosis Factor-alpha-induced Matrix Degradation of Annulus Fibrous Tissue in vitro

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.

Nitric oxide and tumour necrosis factor alpha in the process of pseudoexfoliation glaucoma

AIMTo establish the role of nitric oxide (NO), ascorbic acid and tumour necrosis factor-&#x003b1; (TNF-&#x003b1;) in the pathogenesis of pseudoexfoliation glaucoma (XFG).METHODSOur study included 120 patients who were referred for cataract surgery. All patients were divided into four groups according to clinical findings: XFG, early and late pseudoexfoliation syndrome (XFS), and cataract (without pseudoexfoliation). Serum and aqueous humour levels of the ascorbic acid, NO and TNF-&#x003b1; were measured. The concentrations of the ascorbic acid and NO were measured by an appropriate spectrophotometric method. Enzyme-linked immunosorbent assay (ELISA) was used to determine TNF-&#x003b1; level.RESULTSAqueous humour concentration of ascorbic acid was significantly lower in patients with late XFS (0.61&#x000b1;0.11 mmol/L) and XFG (0.48&#x000b1;0.15 mmol/L) compared to patients with early XFS (0.9&#x000b1;0.15 mmol/L) and cataract (1.16&#x000b1;0.22 mmol/L), while there was no difference in serum concentration in all examined groups. Aqueous humour concentration of NO was significantly higher in patients with XFG (77.7&#x000b1;11.4 &#x000b5;mol/L) compared to patients with early XFS (50.27&#x000b1;9.34 &#x000b5;mol/L) and cataract (49.77&#x000b1;7.1 &#x000b5;mol/L), while serum concentration was increased in the early stage of XFS (73.26&#x000b1;8.29 &#x000b5;mol/L). Aqueous humour level of proinflammatory cytokine TNF-&#x003b1; was increased in patients with XFS (early 460.04&#x000b1;18.32 pg/mL; late 502.42&#x000b1;53.23 pg/mL) and XFG (510.34&#x000b1;43.07 pg/mL), while there was no difference in serum level in all examined groups of patients.CONCLUSIONReduced ascorbic acid and elevated NO and inflammation related cytokine TNF-&#x003b1; level in aqueous humour of the patients with developed XFG suggest that oxidative stress induces local inflammation.

Role of tumor necrosis factor-alpha in zebrafish retinal neurogenesis and myelination

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.

Intragingival injection of Porphyromonas gingivalis-derived lipopolysaccharide induces a transient increase in gingival tumour necrosis factor-a, but not interleukin-6,in anaesthetised rats

This study used in vivo microdialysis to examine the effects of intragingival application of lipopolysaccharide（LPS） derived from Porphyromonas gingivalis（Pg-LPS） on gingival tumour necrosis factor（TNF）-a and interleukin（IL）-6 levels in rats. A microdialysis probe with an injection needle attached to the surface of the dialysis membrane was implanted into the gingiva of the upper incisor. For comparison, the effects of LPS derived from Escherichia coli（Ec-LPS） on IL-6 and TNF-a levels were also analysed. Pg-LPS（1 mg/1 m L） or Ec-LPS（1 or 6 mg/1 m L） was applied by microsyringe, with gingival dialysates collected every hour. Enzyme-linked immunosorbent assay（ELISA） revealed that gingival dialysates contained approximately 389 pg？m L21 of IL-6 basally; basal TNF-a levels were lower than the detection limit of the ELISA. Pg-LPS failed to alter IL-6 levels but markedly increased TNF-a levels, which remained elevated for 2 h after treatment. Neither IL-6 nor TNF-a were affected by Ec-LPS. Reverse transcriptase-polymerase chain reaction（RT-PCR） analysis revealed that the gingiva expresses Toll-like receptor（TLR） 2 and TLR4 m RNA. Immunohistochemical examination showed that TLR2 and TLR4 are expressed by gingival epithelial cells. The present study provides in vivo evidence that locally applied Pg-LPS, but not Ec-LPS, into the gingiva transiently increases gingival TNF-a without affecting IL-6. The present results suggest that TLR2 but not TLR4 expressed on gingival epithelial cells may mediate the Pg-LPS-induced increase in gingival TNF-a in rats.

Use of anti tumor necrosis factor-alpha monoclonal antibody for ulcerative jejunoileitis

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).

Expression of tumor necrosis factor-alpha converting enzyme in liver regeneration after partial hepatectomy

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.

Protective effect of curcumin on tumor necrosis factor-alpha-induced neuronal damage in the rat hippocampus A relationship to the inhibition of neuronal Ca^(2+) influx

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.

AN EXPERIMENTAL STUDY OF THE TUMOUR NECROSIS FACTOR LEVELSIN AQUEOUS HUMOR AFTER TRAUMATIC CATARACT AND INTRAOCULAR LENS IMPLANTATION

Purpose. This paper studies the tumour necrosis factor (TNF) levels in aqueous humor after traumatic cataract extraction and posterior chamber (PC) intraocular lens (IOL) implantation in rabbits,and discusses the effect of TNF on postoperative anterior ocular inflammation. Methods. Twenty seven pigmented rabbits were divided into three groups: for the first group, the IOL were placed in the capsular bag after traumatic cataract extraction; for the second, the Extracapsular cataract extraction without IOL implantation; and for the third, the control group without surgical intervention. On the 1st, 3rd, 7th and 14th day postoperatively, aqueous humor samples were obtained. A modified double antibodies indirect sandwich ELISA was used to detected for the presence of TNF. The data were studied by means of analysis of variance in SAS software. Result. The TNF level was increased in aqueous humor and reached its maximum on the 1st postoperative days after traumatic cataract extraction and PC IOLs implantation, and the TNF levels are significantly higher (P<0 05) on the 1st, 3rd, 7th and 14th day postoperatively in traumatic cataract extraction and PC IOL implanted group than that in the non surgical intervention group and extracapsular cataract extraction group. Conclusions. The increase of TNF levels had a close relationship with presence of the IOL itself which induces the secretion of TNF. This suggested that TNF as the principal mediators of immunological and inflammatory responses, so that may play critical role in anterior ocular inflammative response after traumatic cataract extraction and IOL implantation.

Neuronal injury and tumor necrosis factor-alpha immunoreactivity in the rat hippocampus in the early period of asphyxia-induced cardiac arrest under normothermia

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.

Responses of serum inflammatory factor high-sensitivity C-reactive protein, interleukin-6, and tumor necrosis factor-alpha in elderly males with cerebral infarction Non-randomized concurrent control

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.

Tumor necrosis factor-alpha(TNF-α) in spotted halibut Verasper variegatus at the embryonic and metamorphic stages

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.

Withdrawal of anti-tumour necrosis factor α therapy in inflammatory bowel disease

Anti-tumour necrosis factor α(anti-TNFα) therapy is an established treatment in inflammatory bowel disease.However, this treatment is associated with high costs and the possibility of severe adverse events representing a true challenge for patients, clinicians and health care systems.Consequently, a crucial question is raised namely if therapy can be stopped once remission is achieved and if so, how and in whom.Additionally, in a real-life clinical setting, discontinuation may also be considered for other reasons such as the patient's preference, pregnancy, social reasons as moving to countries or continents with less access, or different local policy or reimbursement.In contrast to initiation of anti-TNFα therapy guidelines regarding stopping of this treatment are missing.As a result, the decision of discontinuation is still a challenging aspect in the use of anti-TNFα therapy.Currently this is typically based on an estimated, case-by-case, benefit-risk ratio.This editorial is intended to provide an overview of recent data on this topic and shed light on the proposed drug withdrawal strategies.

Clinical Implications of Tumor Necrosis Factor-Alpha, Interleukin-6 and Resistin in Coronary Artery Disease

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.