Tumor necrosis factor-stimulated gene-6 ameliorates early brain injury after subarachnoid hemorrhage by suppressing NLRC4 inflammasome-mediated astrocyte pyroptosis

Subarachnoid hemorrhage is associated with high morbidity and mortality and lacks effective treatment.Pyroptosis is a crucial mechanism underlying early brain injury after subarachnoid hemorrhage.Previous studies have confirmed that tumor necrosis factor-stimulated gene-6(TSG-6)can exert a neuroprotective effect by suppressing oxidative stress and apoptosis.However,no study to date has explored whether TSG-6 can alleviate pyroptosis in early brain injury after subarachnoid hemorrhage.In this study,a C57BL/6J mouse model of subarachnoid hemorrhage was established using the endovascular perforation method.Our results indicated that TSG-6 expression was predominantly detected in astrocytes,along with NLRC4 and gasdermin-D(GSDMD).The expression of NLRC4,GSDMD and its N-terminal domain(GSDMD-N),and cleaved caspase-1 was significantly enhanced after subarachnoid hemorrhage and accompanied by brain edema and neurological impairment.To explore how TSG-6 affects pyroptosis during early brain injury after subarachnoid hemorrhage,recombinant human TSG-6 or a siRNA targeting TSG-6 was injected into the cerebral ventricles.Exogenous TSG-6 administration downregulated the expression of NLRC4 and pyroptosis-associated proteins and alleviated brain edema and neurological deficits.Moreover,TSG-6 knockdown further increased the expression of NLRC4,which was accompanied by more severe astrocyte pyroptosis.In summary,our study revealed that TSG-6 provides neuroprotection against early brain injury after subarachnoid hemorrhage by suppressing NLRC4 inflammasome activation-induced astrocyte pyroptosis.

The action mechanism by which C1q/tumor necrosis factor-related protein-6 alleviates cerebral ischemia/reperfusion injury in diabetic mice

Studies have shown that C1q/tumor necrosis factor-related protein-6 (CTRP6) can alleviate renal ischemia/reperfusion injury in mice. However, its role in the brain remains poorly understood. To investigate the role of CTRP6 in cerebral ischemia/reperfusion injury associated with diabetes mellitus, a diabetes mellitus mouse model of cerebral ischemia/reperfusion injury was established by occlusion of the middle cerebral artery. To overexpress CTRP6 in the brain, an adeno-associated virus carrying CTRP6 was injected into the lateral ventricle. The result was that oxygen injury and inflammation in brain tissue were clearly attenuated, and the number of neurons was greatly reduced. In vitro experiments showed that CTRP6 knockout exacerbated oxidative damage, inflammatory reaction, and apoptosis in cerebral cortical neurons in high glucose hypoxia-simulated diabetic cerebral ischemia/reperfusion injury. CTRP6 overexpression enhanced the sirtuin-1 signaling pathway in diabetic brains after ischemia/reperfusion injury. To investigate the mechanism underlying these effects, we examined mice with depletion of brain tissue-specific sirtuin-1. CTRP6-like protection was achieved by activating the sirtuin-1 signaling pathway. Taken together, these results indicate that CTRP6 likely attenuates cerebral ischemia/reperfusion injury through activation of the sirtuin-1 signaling pathway.

Predictors and optimal management of tumor necrosis factor antagonist nonresponse in inflammatory bowel disease:A literature review

Tumor necrosis factor-α(TNF-α)antagonists,the first biologics approved for treating patients with inflammatory bowel disease(IBD),are effective for the induction and maintenance of remission and significantly improving prognosis.However,up to one-third of treated patients show primary nonresponse(PNR)to anti-TNF-αtherapies,and 23%-50%of IBD patients experience loss of response(LOR)to these biologics during subsequent treatment.There is still no recognized predictor for evaluating the efficacy of anti-TNF drugs.This review summarizes the existing predictors of PNR and LOR to anti-TNF in IBD patients.Most predictors remain controversial,and only previous surgical history,disease manifestations,drug concentrations,antidrug antibodies,serum albumin,some biologic markers,and some genetic markers may be potentially predictive.In addition,we also discuss the next steps of treatment for patients with PNR or LOR to TNF antagonists.Therapeutic drug monitoring plays an important role in treatment selection.Dose escalation,combination therapy,switching to a different anti-TNF drug,or switching to a biologic with a different mechanism of action can be selected based on the concentration of the drug and/or antidrug antibodies.

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.

Joint Detection of Serum Vitamin D,Body Mass Index,and Tumor Necrosis Factor Alpha for the Diagnosis of Crohn’s Disease

Objective Vitamin D(VD)deficiency was reported to contribute to the progression of Crohn’s disease(CD)and affect the prognosis of CD patients.This study investigated the role of serum VD,body mass index(BMI),and tumor necrosis factor alpha(TNF-α)in the diagnosis of Crohn’s disease.Methods CD patients(n=76)and healthy subjects(n=76)were enrolled between May 2019 and December 2020.The serum 25-hydroxyvitamin D[25(OH)D]levels,BMI,and TNF-αlevels,together with other biochemical parameters,were assessed before treatment.The diagnostic efficacy of the single and joint detection of serum 25(OH)D,BMI,and TNF-αwas determined using receiver operating characteristic(ROC)curves.Results The levels of 25(OH)D,BMI,and nutritional indicators,including hemoglobin,total protein,albumin,and high-density lipoprotein cholesterol,were much lower,and the TNF-αlevels were much higher in the CD patients than in the healthy subjects(P<0.05 for all).The areas under the ROC curve for the single detection of 25(OH)D,BMI,and TNF-αwere 0.887,0.896,and 0.838,respectively,with the optimal cutoff values being 20.64 ng/mL,19.77 kg/m^(2),and 6.85 fmol/mL,respectively.The diagnostic efficacy of the joint detection of 25(OH)D,BMI,and TNF-αwas the highest,with an area under the ROC curve of 0.988(95%CI:0.968–1.000).Conclusion The joint detection of 25(OH)D,TNF-α,and BMI showed high sensitivity,specificity,and accuracy in CD diagnosis;thus,it would be effective for the diagnosis of CD in clinical practice.

Acute heart failure as an adverse event of tumor necrosis factor inhibitor therapy in inflammatory bowel disease:A review of the literature

Tumor necrosis factor inhibitors(anti-TNFs)are widely used therapies for the treatment of inflammatory bowel diseases(IBD);however,their administration is not risk-free.Heart failure(HF),although rare,is a potential adverse event related to administration of these medications.However,the exact mechanism of development of HF remains obscure.TNFαis found in both healthy and damaged hearts.Its effects are concentration-and receptor-dependent,promoting either cardio-protection or cardiomyocyte apoptosis.Experimental rat models with TNFαreceptor knockout showed increased survival rates,less reactive oxygen species formation,and improved diastolic left ventricle pressure.However,clinical trials employing anti-TNF therapy to treat HF had disappointing results,suggesting abolishment of the cardioprotective properties of TNFα,making cardiomyocytes susceptible to apoptosis and oxidation.Thus,patients with IBD who have risk factors should be screened for HF before initiating anti-TNF therapy.This review aims to discuss adverse events associated with the administration of anti-TNF therapy,with a focus on HF,and propose some approaches to avoid cardiac adverse events in patients with IBD.

Infliximab vs adalimumab:Points to consider when selecting antitumor necrosis factor agents in pediatric patients with Crohn’s disease

Biologic agents with various mechanisms against Crohn’s disease(CD)have been released and are widely used in clinical practice.However,two anti-tumor necrosis factor(TNF)agents,infliximab(IFX)and adalimumab(ADL),are the only biologic agents approved by the Food and Drug Administration for pediatric CD currently.Therefore,in pediatric CD,the choice of biologic agents should be made more carefully to achieve the therapeutic goal.There are currently no headto-head trials of biologic agents in pediatric or adult CD.There is a lack of accumulated data for pediatric CD,which requires the extrapolation of adult data for the positioning of biologics in pediatric CD.From a pharmacokinetic point of view,IFX is more advantageous than ADL when the inflammatory burden is high,and ADL is expected to be advantageous over IFX in sustaining remission in the maintenance phase.Additionally,we reviewed the safety profile,immunogenicity,preference,and compliance between IFX and ADL and provide practical insights into the choice of anti-TNF therapy in pediatric CD.Careful evaluation of clinical indications and disease behavior is essential when prescribing anti-TNF agents.In addition,factors such as the efficacy of induction and maintenance of remission,safety profile,immunogenicity,patient preference,and compliance play an important role in evaluating and selecting treatment options.

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.

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.

Long-term outcome of stem cell transplantation with and without anti-tumor necrotic factor therapy in perianal fistula with Crohn’s disease

BACKGROUND Stem cell transplantation is a promising therapeutic option for curing perianal fistula in Crohn’s disease(CD).Anti-tumor necrotic factor(TNF)therapy combined with drainage procedure is effective as well.However,previous studies are limited to proving whether the combination treatment of biologics and stem cell transplantation improves the effect of fistula closure.AIM This study aimed to evaluate the long-term outcomes of stem cell transplantation and compare Crohn’s perianal fistula(CPF)closure rates after stem cell transplantation with and without anti-TNF therapy,and to identify the factors affecting CPF closure and recurrence.METHODS The patients with CD who underwent stem cell transplantation for treating perianal fistula in our institution between Jun 2014 and December 2022 were enrolled.Clinical data were compared according to anti-TNF therapy and CPF closure.RESULTS A total of 65 patients were included.The median age of females was 26 years(range:21-31)and that of males was 29(44.6%).The mean follow-up duration was 65.88±32.65 months,and complete closure was observed in 50(76.9%)patients.The closure rates were similar after stem cell transplantation with and without anti-TNF therapy(66.7%vs 81.6%at 3 year,P=0.098).The patients with fistula closure had short fistulous tract and infrequent proctitis and anorectal stricture(P=0.027,0.002,and 0.008,respectively).Clinical factors such as complexity,number of fistulas,presence of concurrent abscess,and medication were not significant for closure.The cumulative 1-,2-,and 3-year closure rates were 66.2%,73.8%,and 75.4%,respectively.CONCLUSION Anti-TNF therapy does not increase CPF closure rates in patients with stem cell transplantation.However,both refractory and non-refractory CPF have similar closure rates after additional anti-TNF therapy.Fistulous tract length,proctitis,and anal stricture are risk factors for non-closure in patients with CPF after stem cell transplantation.

Tumor necrosis factor-α and interleukin-6 in cirrhotic patients with spontaneous bacterial peritonitis

AIM:To evaluate the role of tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6) in cirrhotic patients who have hepatic and renal impairment with spontaneous bacterial peritonitis(SBP).METHODS:We prospectively studied 120 cirrhotic patients with SBP and 80 cirrhotic patients with sterile ascitic fluid.They included 144 males and 56 females with ages ranging between 34 and 62 years.The diagnosis of cirrhosis was established by clinical and laboratory criteria that did not require histological confirmation.The severity of underlying liver disease was evaluated using Pugh's modification of Child's criteria(Child-Pugh scores).Ascitic fluid was sent to the laboratory for cell count,culture,sensitivity testing,and measurement of chemical elements(i.e.,albumin,glucose).Specimens were inoculated into aerobic and anaerobic blood culture bottles.Serum and ascitic fluid were also collected in sterile tubes at study entry(before the initiation of antibiotic treatment) and 48 h later.Assays for TNF-α and IL-6 in the serum and ascitic fluid were performed with an immunoenzymometric assay using manufacture's instructions.RESULTS:Cytokine levels in serum and ascitic fluid were significantly higher in the patients with SBP.(plasma TNF-α:135.35 ng/mL ± 11.21 ng/mL vs 92.86 ng/mL ± 17.56 ng/mL,P < 0.001;plasma IL-6:32.30 pg/mL ± 7.07 pg/mL vs 12.11 pg/mL ± 6.53 pg/mL,P < 0.001;ascitic fluid TNF-α:647.54 ± 107.11 ng/mL vs 238.43 ng/mL ± 65.42 ng/mL,P < 0.001);ascitic fluid IL-6:132.84 ng/mL ± 34.13 vs 40.41 ± 12.85 pg/mL,P < 0.001).About 48(40%) cirrhotic patients with SBP developed renal and hepatic impairment and showed significantly higher plasma and ascitic fluid cytokine levels at diagnosis of infection.[(plasma TNF-α:176.58 ± 17.84 vs 135.35 ± 11.21 ng/mL)(P < 0.001) and(IL-6:57.83 ± 7.85 vs 32.30 ± 7.07 pg/mL)(P < 0.001);ascitic fluid TNF-α:958.39 ± 135.72 vs 647.54 ± 107.11 ng/mL,(P < 0.001),ascitic fluid IL-6:654.74 ± 97.43 vs 132.84 ± 34.13 pg/mL,(P < 0.001)].Twenty nine patients(60.4%) with SBP and renal impairment died whereas,only four patients(5.55%) with SBP but without renal impairment died from gastrointestinal hemorrhage(P < 0.0005).CONCLUSION:It appears that TNF-α production may enhance liver cell injury and lead to renal impairment.This correlated well with the poor prognosis and significantly increased mortality associated with SBP in cirrhotic patients.

The Change of Interleukin-6 and Tumor Necrosis Factor in Patients with Obstructive Sleep Apnea Syndrome

The levels of lipopolysaccharide (LPS) induced interleukin 6 (IL 6) and tumor necrosis factor α (TNF α) expression in culture of peripheral blood mononuclear cells (PBMC) and the plasma levels of IL 6 and TNF α in the patients with obstructive sleep apnea syndrome (OSAS) were measured and the relationship between OSAS and IL 6 or TNF α expression studied. Both IL 6 and TNF α were detected by using ELISA in 22 patients with OSAS and 16 normal controls. The levels of LPS induced IL 6 (787.82±151.97 pg/ml) and TNF α (4165.45±1501.43 pg/ml) expression in the supernatant of the culture of PBMC and plasma level of IL 6 (50.67±4.70 pg/ml) and TNF α (299.09±43.57 pg/ml) in the patients with OSAS were significantly higher than those in the normal controls (in the supernatant of the culture of PBMC: 562.69±197.54 pg/ml and 1596.25±403.08 pg/ml respectively; in the plasma: 12.69±2.75 pg/ml and 101.88±21.27 pg/ml respectively). There were significantly positive correlation between the levels of IL 6 and TNF α and the percentage of time of apnea and hyponea, as well as the percentage of time spending at SaO 2 below 90 % in the total sleep time. It was concluded that LPS induced IL 6 and TNF α levels as well as plasma IL 6 and TNF α levels in the patients with OSAS were up regulated, which may be associated with the pathogenesis of OSAS.

Relationship between tumor necrosis factor-α and liver fibrosis

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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-α)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-αmRNA 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-αmRNA in the SO group was decreased compared with that in the I/R group(P<0.05) TNF-αmRNA 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-α production in the liver triggers hepatic I/R injury through a cascade.

Influence of granulocyte-macrophage colonystimulating factor and tumor necrosis factor on anti-hepatoma activities of human dendritic cells

INTRODUCTIONDendritic cells (DCs) play a key regulatory role inantitumor immunity,especially in its immuneaccessory role via MHC-Ⅰ molecules.We haverecently reported that DCs were able to enhance thekilling activity of Lymphokine and PHA activatedkiller (LPAK) cells in vitro.In the presentstudy,we evaluated the effects of GM-CSF andTNF upon antitumor activities of freshly

Hepatitis B virus X protein up-regulates tumor necrosis factor-α expression in cultured mesangial cells via ERKs and NF-κB pathways

Objective:To investigate the effects of hepatitis B virus(HBV)X protein(HBx)on the expression of tumor necrosis factor-α(TNF-α)in glomerular mesangial cells(GMCs)and the underlying intracellular signal pathways.Methods:The plasmid pCI-neo-X that carries the X gene of hepatitis B virus was transfected into cultured GMCs.HBx expression in the transfected GMCs was assessed by Western-blot.TNF-αprotein and mRNA were assessed by ELISA and semi-quantitative RT-PCR,respectively.Three kinase inhibitors-U0126,an inhibitor of extracellular signal-regulated kinases(ERKs);lactacvstin,an inhibitor of nuclear factor-κB(NF-κB);and SB203580,a selective inhibitor of p38 MAP kinase(p38 MAPK)were used to determine which intracellular signal pathways may underlie the action of HBx on TNF-αexpression in transfected GMCs.Results:A significant increase in HBx expression in pCI-neo-X transfected GMCs was detected at 36 h and 48 h,which was not affected by any of those kinase inhibitors mentioned above.A similar increase in the expression of both TNF-αprotein and mRNA was also observed at 36 h and 48 h,which was significantly decreased in the presence of U0126 or lactacytin,but not SB203580.Conclusions:HBx upregulates TNF-αexpression in cultured GMCs,possibly through ERKs and NF-κB pathway,but not p38 MAPK pathway.

Helicobacter pylori tumor necrosis factor-α inducing protein promotes cytokine expression via nuclear factor-κB

AIM:To study the effects of Helicobacter pylori(H. pylori)tumor necrosis factor-α(TNF)inducing protein (Tip-α)on cytokine expression and its mechanism. METHODS:We cloned Tip-αfrom the H.pylori strain 26695,transformed Escherichia coli with an expression plasmid,and then confirmed the expression product by Western blotting.Using different concentrations of Tip-αthat affected SGC7901 and GES-1 cells at different times,we assessed cytokine levels using enzyme-linked immunosorbent assay.We blocked SGC7901 cells with pyrrolidine dithiocarbamate(PDTC),a specific inhibitor of nuclear factorκB(NF-κB).We then detected interleukin(IL)-1βand TNF-αlevels in SGC7901 cells. RESULTS:Western blot analysis using an anti-Tip-α antibody revealed a 23-kDa protein,which indicated that recombinant Tip-αprotein was recombined successfully.The levels of IL-1β,IL-8 and TNF-αwere sig-nificantly higher following Tip-αinterference,whether GES-1 cells or SGC-7901 cells were used(P<0.05).However,the levels of cytokines(including IL-1β,IL-8 and TNF-α)secreted by SGC-7901 cells were greater than those secreted by GES-1 cells following treatment with Tip-αat the same concentration and for the same duration(P<0.05).After blocking NF-κB with PDTC, the cells(GES-1 cells and SGC-7901 cells)underwent interference with Tip-α.We found that IL-1βand TNF-αlevels were significantly decreased compared to cells that only underwent Tip-αinterference(P<0.05). CONCLUSION:Tip-αplays an important role in cyto-kine expression through NF-κB.

Tumor necrosis factor-α inhibitor therapy and fetal risk:A systematic literature review

Tumor necrosis factor-α inhibitors (anti-TNFs) are effective in the treatment of inflammatory bowel disease (IBD) recalcitrant to conventional medical therapy. As the peak incidence of IBD overlaps with the prime reproductive years, it is crucial to establish pharmacologic regimens for women of childbearing age that achieve effective disease control without posing significant fetal harm. A systematic literature review was performed to identify all human studies with birth outcomes data after maternal exposure to infliximab, adalimumab, or certolizumab pegol within 3 mo of conception or during any trimester of pregnancy. Live births, spontaneous abortions or stillbirths, preterm or premature births, low birth weight or small for gestational age infants, and congenital abnormalities were recorded. Fifty selected references identified 472 pregnancy exposures. The subsequent review includes general information regarding anti-TNF therapy in pregnancy followed by a summary of our findings. The benefits of biologic modalities in optimizing disease control during pregnancy must be weighed against the potential toxicity of drug exposure on the developing fetus. Although promising overall, there is insufficient evidence to prove absolute safety for use of anti-TNFs during pregnancy given the limitations of available data and lack of controlled trials.

Claudin 1 mediates tumor necrosis factor alpha-induced cell migration in human gastric cancer cells

AIM:To investigate the role of claudin 1 in the regulation of genes involved in cell migration and tumor necrosis factor alpha(TNF-α)-induced gene expression in human gastric adenocarcinoma cells.METHODS:Knockdown experiments were conducted with claudin 1 small interfering RNA(si RNA),and theeffects on the cell cycle,apoptosis,migration and invasion were analyzed in human gastric adenocarcinoma MKN28 cells.The gene expression profiles of cells were analyzed by microarray and bioinformatics.RESULTS:The knockdown of claudin 1 significantly inhibited cell proliferation,migration and invasion,and increased apoptosis.Microarray analysis identified 245genes whose expression levels were altered by the knockdown of claudin 1.Pathway analysis showed that the top-ranked molecular and cellular function was the cellular movement related pathway,which involved MMP7,TNF-SF10,TGFBR1,and CCL2.Furthermore,TNFand nuclear frctor-κB were the top-ranked upstream regulators related to claudin 1.TNF-αtreatment increased claudin 1 expression and cell migration in MKN28 cells.Microarray analysis indicated that the depletion of claudin1 inhibited 80%of the TNF-α-induced m RNA expression changes.Further,TNF-αdid not enhance cell migration in the claudin 1 si RNA transfected cells.CONCLUSION:These results suggest that claudin 1 is an important messenger that regulates TNF-α-induced gene expression and migration in gastric cancer cells.A deeper understanding of these cellular processes may be helpful in establishing new therapeutic strategies for gastric cancer.

Blood glucose changes surrounding initiation of tumor-necrosis factor inhibitors and conventional disease-modifying anti-rheumatic drugs in veterans with rheumatoid arthritis

AIM To determine the scope of acute hypoglycemic effects for certain anti-rheumatic medications in a large retrospective observational study. METHODS Patients enrolled in the Veterans Affairs Rheumatoid Arthritis (VARA) registry were selected who, during follow-up, initiated treatment with tumor necrosis factor inhibitors (TNFi's, including etanercept, adalimumab, infliximab, golimumab, or certolizumab), prednisone, or conventional disease-modifying anti-rheumatic drugs(DMARDs), and for whom proximate random blood glucose (RBG) measurements were available within a window 2-wk prior to, and 6 mo following, medication initiation. Similar data were obtained for patients with proximate values available for glycosylated hemoglobin A1C values within a window 2 mo preceding, and 12 mo following, medication initiation. RBG and A1C measurements were compared before and after initiation events using paired t-tests, and multivariate regression analysis was performed including established comorbidities and demographics.RESULTS Two thousands one hundred and eleven patients contributed at least one proximate measurement surrounding the initiation of any examined medication. A significant decrease in RBG was noted surrounding 653 individual hydroxychloroquine-initiation events(-3.68 mg/dL, P = 0.04), while an increase was noted for RBG surrounding 665 prednisone-initiation events(+5.85 mg/d L, P < 0.01). A statistically significant decrease in A1C was noted for sulfasalazine initiation, as measured by 49 individual initiation events(-0.70%, P < 0.01). Multivariate regression analyses, using methotrexate as the referent, suggest sulfasalazine (β =-0.58, P = 0.01) and hydroxychloroquine(β =-5.78, P = 0.01) use as predictors of lower post-medicationinitiation RBG and A1C values, respectively. Analysis by drug class suggested prednisone (or glucocorticoids) as predictive of higher medication-initiation event RBG among all start events as compared to DMARDs, while this analysis did not show any drug class-level effect for TNFi. A diagnosis of congestive heart failure(β = 4.69, P = 0.03) was predictive for higher post-initiation RBG values among all medication-initiation events.CONCLUSION No statistically significant hypoglycemic effects surrounding TNFi initiation were observed in this large cohort. Sulfasalazine and hydroxychloroquine may have epidemiologically significant acute hypoglycemic effects.