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.

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.

Tumor necrosis factor alpha receptor 1 deficiency in hepatocytes does not protect from non-alcoholic steatohepatitis, but attenuates insulin resistance in mice

BACKGROUND End-stage liver disease caused by non-alcoholic steatohepatitis(NASH)is the second leading indication for liver transplantation.To date,only moderately effective pharmacotherapies exist to treat NASH.Understanding the pathogenesis of NASH is therefore crucial for the development of new therapies.The inflammatory cytokine tumor necrosis factor alpha(TNF-α)is important for the progression of liver disease.TNF signaling via TNF receptor 1(TNFR1)has been hypothesized to be important for the development of NASH and hepatocellular carcinoma in whole-body knockout animal models.AIM To investigate the role of TNFR1 signaling in hepatocytes for steatohepatitis development in a mouse model of diet-induced NASH.METHODS NASH was induced by a western-style fast-food diet in mice deficient for TNFR1 in hepatocytes(TNFR1ΔHEP)and their wild-type littermates(TNFR1fl/fl).Glucose tolerance was assessed after 18 wk and insulin resistance after 19 wk of feeding.After 20 wk mice were assessed for features of NASH and the metabolic syndrome such as liver weight,liver steatosis,liver fibrosis and markers of liver inflammation.RESULTS Obesity,liver injury,inflammation,steatosis and fibrosis was not different between TNFR1ΔHEP and TNFR1fl/fl mice.However,Tnfr1 deficiency in hepatocytes protected against glucose intolerance and insulin resistance.CONCLUSION Our results indicate that deficiency of TNFR1 signaling in hepatocytes does not protect from diet-induced NASH.However,improved insulin resistance in this model strengthens the role of the liver in glucose homeostasis.

EFFECTS OF PHYTOLACCA ACINOSA POLYSACCHARIDES I ON CYTOTOXICITY OF MACROPHAGES AND ITS PRODUCTION OF TUMOR NECROSIS FACTOR AND INTERLEUKIN 1

The in vivo effects of Phytolacca acinosa poly-saccharides I (PEP-I) on immunologic cytotoxicity of mouse peritoneal macrophages and its production of tumor necrosis factor (TNF) and interleukin 1 (IL-1) were studied. PEP-I 80 or 160 mg kg was given ip twice every 4 day. Both doses were found to have significant enhancing activity on macrophages cytotoxicity against S180 sarcoma cells and malignant transformed fibroblast L929 cells. Peritoneal activated macrophages were incubated with LPS for 2 and 24 hrs to induce TNF and IL-1, respectively. The TNF and IL-1 activities were tested from cytotoxicity against L929 cells in an absorbence assay of enzymatic reaction and proliferation of thymocytes co-stimulated assay separately. The optimal time for TNF production was found on day 8. Significant increases in TNF and IL-1 were observed. In comparison of the effect of PEP-I on TNF with that of known priming agent BCG, there was no difference between them, but PEP-I had a high effect on IL-1. These results suggest that cytotoxicity of macrophages primed by PEP-I is closely related to its TNF and IL-1 production.

Effect of Combination of Bushen Jianpi Recipe (补肾健脾方) and Erythropoietin on Serum Tumor Necrosis Factor a in Patients with Anemia

Objective: To study the effect of treatment of renal anemia by combination of Bushen Jianpi Recipe (补贤健脾方, BJR, a Chinese experienced recipe for supplementing Shen and supporting Pi) and low dosage erythropoietin (EPO), and the influence of treatment on change of serum tumor necrosis factor α (TNF-α) so as to explore the possible mechanism of integrative Chinese and Western medicine (ICWM) in treating renal anemia. Methods: Patients with renal anemia were randomly divided into two groups, the ICWM group and the control group, supporting treatment such as dialysis, supplementing of ferrous, foliac acid and vitamin B12, was given to both groups. Additionally, to the ICWM group, 50 IU/kg of EPO subcutaneous injection for twice every week, and oral intake of BJR, one dose per day taken in two parts, were given, and to the control group, EPO alone, 50IU/kg by subcutaneous injecting, 3 times perweek, was given. The therapeutic course for two groups was 3 months. Blood levels of hemoglobin (Hb), hematocrit (Hct), TNF-α were measured before treatment and the therapeutic effect was observed. Results: After treatment, the levels of Hb and Hct increased significantly in both groups (P<0. 01) , comparison between the two groups in Hb and Hct after treatment for 3 months showed significant difference (P<0. 05). The serum level of TNF-α was markedly higher than normal range in both groups before treatment, it significantly lowered after treatment in the ICWM group (P< 0.05), but unchanged in the control group. Conclusion: Combination of BJR and EPO could significantly inhibit the production of TNF-α, this may be an important factor for ICWM in effectively improving sensitivity to EPO.Original article on CJITWM (Chin) 2004;24 (2): 106

Tumor necrosis factor alpha inhibits in vitro bovine embryo development through a prostaglandin mediated mechanism

Mastitis or other infectious diseases have been related to reduced fertility in cattle. Inflammatory cytokines such as tumor necrosis factor α （TNFα are released in response to infection and may have negative effects on embryo development, in the current study the effect of exposure to TNFα on the development of in vitro fertilized bovine embryos was examined. Indomethacin, a prostaglandin synthesis inhibitor, was used to determine if blockade of prostaglandin synthesis would alter the effects of TNFα Ovaries were obtained from a local abattoir and immature COC were isolated from 2-10 mm follicles, in vitro matured and fertilized. After fertilization, groups of presumptive zygotes were randomly placed into either control development medium, medium containing 25 ng/mL TNFα or medium containing 25 ng/mL TNFα plus 1 μg/mL indomethacin. The proportion of blastocysts formed was assessed at day 7 of culture. Fewer embryos exposed to TNFα alone reached the blastocyst stage （17.5 ± 2.4%, P 〈 0.01） compared with controls （30.5 ± 2.4%） or embryos developed in TNFα plus indomethacin （25.8 ± 2.8%）. There was no difference between control embryos and embryos developed in TNFα plus indomethacin. These results indicate that TNFα is inhibitory to the in vitro development of bovine embryos and that this inhibition may be mediated by prostaglandins because it can be blocked by indomethacin.

Changes in tumor necrosis factor alpha and myeloper-oxidase in mouse models of local cerebral infarction induced by photochemical method

BACKGROUND： Lots of evidences have demonstrated that acute inflammatory reaction plays an important role in cerebral ischemia and cerebral ischemia/reperfusion injury. Tumor necrosis factor （TNF）, as one of important inflammatory cytokines, also participates in the injury. OBJECTIVE： To observe the changes in TNF-α expression and myeloperoxidase （MPO） activity of mouse models of local cerebral infarction induced by photochemical method, and analyze the correlation of TNF-α expression and MPO activity. DESIGN： Randomized controlled experiment. SETTING： Laboratory of Cerebral Microcirculation, Taishan Medical College. MATERIALS： Sixty involved male adult Kunming mice were provided by the Experimental Animal Center of Shandong University. TNF-α primary antibody, kits for enzyme-linked immunosorbent assay（ELISA） and streptavidin-biotin complex immunohistochemical dyeing kit were purchased from Boster Company（Wuhan）. MPO kit was purchased from Jiancheng Bioengineering Institute （Nanjing）. Cold light source was developed by Hengfa Co.,Ltd.（ LG-150, Xuzhou）. METHODS： This experiment was carried out in the Laboratory of Cerebral Microcirculation of Taishan Medical College between July 2004 and July 2005. The involved 60 Kumning mice were randomized into 3 groups： normal control group （n =6）, sham-operation group （n =6） and model group （n =48）. Mice in the model group were observed at 30 minutes, 1, 3, 6, 12, 24, 48 and 72 hours after illumination, separately, 6 mice at each time point. In the model group, mice models of local cerebral infarction were developed as follows： The mice were anesthetized to expose left skulls. Taking 2 mm left to sagittal suture and 2 mm posterior to coronal suture as center, a field with diameter of 3 mm for illumination was set. The optical fiber detecting head of cold light source was vertically close to exposed skull. The mice were injected with rose Bengal for 5 minutes, and then cold light source was open for 10 minutes, Illumination was omitted in the sham-operation group. Mice in the control group were not modeled. At postoperative 6 hours, TNF-α expression in infracted-side cortex was detected with immunohistochemical method and ELISA, and MPO activity in infracted-side cortex with chromatometry. MPO activity could reflect the infiltration degree of neutrophils in tissue. Stronger activity indicated severer infiltration. Single-factor analysis of variance was used for comparison among groups, q test for pairwise comparison and correlative analysis for detecting the inter-parameter correlation. MAIN OUTCOME MEASURES： Changes in TNF-α expression and MPO activity of left cortex of mice in each group. RESULTS： Sixty mice were involved in the final analysis. After cerebral infarction, TNF-α positive cells were neurons and glial cells mainly, distributing in and around the infarct region. TNF-α expression in cortex of mice of sham-operation group was （615.7 ±16.1 ） ng/L, and that of model group increased to （792.2± 17.8） ng/L at 3 hours after illumination, and reached peak [ （921.9±23.9） ng/L] at 6 hours after illumination, and decreased to （848.0±30.6） ng/L at 12 hours after illumination and recovered to the normal level [ （625.3 ± 14.3） ng/L] at 72 hours after illumination. MPO activity of sham-operation group was （7.151±0.433） nkat/g, and that of model group increased to （10.469±0.600） nkat/g at 3 hours after illumination, reached the peak [ （ 15.486 ± 0.650） nkat/g] at 12 hours after illumination, decreased to （11.052 ± 0,617） nkat/g at 24 hours after illumination and recovered to the normal level [ （7.418 ± 0.617） nkat/g] at 72 hours after illumination. Change of MPO activity lagged behind that of TNF-α, and correlative analysis showed that the both were positively correlated （r =0.953, P 〈 0.01 ） . CONCLUSION： In the acute stage of cerebral infarction of mice induced by photochemical method, TNF-α expression in infarcted-side cortex is closely related with infiltration of neutrophils. TNF-α induces inflammatory cells to intrude into ischemic brain tissue, and participates in the inflammatory reaction process at the early stage of cerebral ischemia.

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.

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.

Moxibustion Treatment Restoring the Intestinal Epithelium Barrier in Rats with Crohn's Disease by Down-Regulating Tumor Necrosis Factor Alpha,Tumor Necrosis Factor Receptor 1,and Tumor Necrosis Factor Receptor 2

Objective： To investigate whether moxibustion regulates tumor necrosis factor alpha （TNF-α）, tumor necrosis factor receptor 1 （TNFR1）, and TNFR2 in the intestinal mucosa and to explore whether moxibustion could be used by means of this mechanism, to repair the intestinal epithelium barrier disruption in Crohn＇s disease （CD）. Methods： The CD rat models were established by tdnitrobenzene sulfonic acid （TNBs）, randomly divided into a model control （MC） group, an herb-partition moxibustion （HPM） group, a mild-warm moxibustion （MWM） group, and a salicylazosulfapyridine （SASP） group, and all were compared with a normal control （NC） group. The HPM and MWM groups were treated by moxibustion at Tianshu （ST25） and Qihai （RN6） for 14 days, and the SASP group obtained the SASP solution orally for the same pedod of time. The intestinal epithelium morphology and TNF-α, TNFR1, and TNFR2 contents were observed by the transmission electron microscopy and enzyme linked immunosorbent assay. Results： The sevedty of morphological changes in CD intestinal epithelium was obviously improved, and the levels of TNF-α, TNFR1, and TNFR2 in the intestinal mucosa all significantly decreased in the HPM and MWM groups. However, there were no significant differences between the HPM and MWM groups. Conclusion： The moxibustion therapies （HPM and MWM） could reduce intestinal inflammation and restore intestinal epithelium barrier disruption in CD, which might be due to down- regulating TNF- α, TNFR1, and TNFR2 in intestinal mucosa and improving intestinal epithelium morphology.

Effect of cholinesterase inhibitor galanthamine on circulating tumor necrosis factor alpha in rats with lipopolysaccharideinduced peritonitis

Background The nervous system, through the vagus nerve and its neurotransmitter acetylcholine, can down-regulate the systemic inflammation in vivo, and recently, a role of brain cholinergic mechanisms in activating this cholinergic anti-inflammatory pathway has been indicated. Galanthamine is a cholinesterase inhibitor and one of the centrally acting cholinergic agents available in clinic. This study aimed to evaluate the effect of galanthamine on circulating tumor necrosis factor alpha （TNF-a） in rats with lipopolysaccharide-induced peritonitis and the possible role of the vagus nerve in the action of galanthamine. Methods Rat models of lipopolysaccharide-induced peritonitis and bilateral cervical vagotomy were produced. In the experiment 1, the rats were randomly divided into control group, peritonitis group, and peritonitis groups treated with three dosages of galanthamine. In the experiment 2, the rats were randomly divided into sham group, sham plus peritonitis group, sham plus peritonitis group treated with galanthamine, vagotomy plus peritonitis group, and vagotomy plus peritonitis group treated with galanthamine. The levels of plasma TNF-α were determined in every group. Results The level of circulating TNF-α was significantly increased in rats after intraperitoneal injection of endotoxin. Galanthamine treatment decreased the level of circulating TNF-α in rats with lipopolysaccharide-induced peritonitis, and there was significant difference compared with rats with lipopolysaccharide-induced peritonitis without treatment. The 3 mg/kg dosage of galanthamine had the most significant inhibition on circulating TNF-α level at all the three tested doses. Galanthamine obviously decreased the TNF-a level in rats with lipopolysaccharide-induced peritonitis with sham operation, but could not decrease the TNF-α level in rats with lipopolysaccharide-induced peritonitis with vagotomy. Conclusion Cholinesterase inhibitor galanthamine has an inhibitory effect on TNF-α release in rats with Iipopolysaccharide-induced peritonitis, and the vagus nerve plays a role in the process of the action of galanthamine.

Tumor necrosis factor alpha affect hydrocortisone expression in mice adrenal cortex cells mainly through tumor necrosis factor alpha-receptor 1

Background Tumor necrosis factor alpha （TNF-α） is important in promoting relative adrenal insufficiency （RAI） due to systemic inflammatory response syndrome （SIRS）. We identified the TNF-α receptor involved in the inhibition of adrenal corticotrophin （ACTH）-stimulated hydrocortisone release by studying the expression of TNF-α receptors in adrenal cortex Y1 cells and the effect of downregulating TNF receptors on ACTH-stimulated hydrocortisone release. Methods We used real-time PCR and immunocytochemistry to evaluate the expression of TNF receptors on Y1 cells. TNF-receptor 1 （TNF-R1） DNA fragments corresponding to the short hairpin RNA （shRNA）-sequences were synthesized and cloned into pcDNATM 6.2-GW/EmGFP expression vector. Knockdown efficiency of TNF-R1 expression was evaluated in miRNA transfected and mock-miRNA transfected Y1 cells by quantitative real-time PCR （Q-PCR）. Hydro- cortisone expression levels were determined in TNF-Rl-knockdown and control Y1 cells treated with TNF-α and ACTH. Results Mouse adrenal cortex Y1 cells were positive for type I TNF-R1, but not type II TNF-receptor （TNF-R2）. Blocking TNF-R1 expression resulted in loss of TNF-a-mediated inhibition of ACTH-stimulated hydrocortisone expression suggesting a role for the TNF-R1 related signaling pathway in ACTH-stimulated hydrocortisone synthesis. Conclusion The inhibitory effect of TNF-α on ACTH-stimulated hydrocortisone synthesis was mediated via TNF-R1 in adrenal cortex.

NO ASSOCIATION BETWEEN TUMOR NECROSIS FACTOR ALPHA AND OBSESSIVE COMPULSIVE DISORDER IN CHINESE HAN POPULATION

Objective To investigate association between tumor necrosis factor alpha (TNF-α) and obsessive compulsive disorder (OCD) in Chinese Han population.Methods Plasma concentrations of TNF-α were measured in 61 drug-free patients who fulfilled DSM-Ⅳ criteria for OCD and 93 healthy controls.TNF-α concentrations in blood were determined by enzyme-linked immunosorbent assay (ELISA).Two polymorphisms of TNF-α gene were investigated in the same patients and healthy controls:-308 G/A and-238 G/A.The allelic and genotypic frequencies of these polymorphisms were examined by using DNA sequencing method.Results Plasma levels of TNF-α did not differ between patients and controls (P=0.292).No significant results were observed for any of the alleles at the-308 G/A or-238 G/A polymorphism of the TNF-α gene.Finally a haplotype consisting of genotypes of these two markers was also examined.No association was observed for any haplotype (P=0.108).Conclusion No significant differences were observed between patients and controls in plasma levels of TNF-α.There is no association between the-308 G/A and-238 G/A TNF-α gene polymorphisms and OCD in our Chinese samples.However,the results need to be replicated in larger samples.

Anti Cervix Cancer Activity of Co-immobilized Tumor Necrosis Factor-α and Interferon-γ

Tumor necrosis factor α （TNF-α） and interferon-γ （IFN-γ） are cytokines with strong antitumor activities. They were reacted with a photoactive arylazide-4-azidobenzoic acid, resulting in photoactive TNF-α and IFN-γ. The infrared （IR） spectra of these products showed the characteristic absorption of an azido group at 2127 cm^-1. By photo-immobilization, this modified TNF-α and IFN-γ were immobilized on polystyrene membranes for cell culture to prepare biomaterials. The micro-morphology of photoactive cytokines was observed with a scanning electron microscope （SEM）. The inhibitory effect on growth of Hela cells and inducing apoptosis activity of these two cytokines were analyzed by growth curve, transmission electron microscope （TEM） and fluorescence active cell sorter （FACS）. The results showed that co-immobilization of IFN-γ and TNF-α had significant inhibitory effect on growth of Hela cells, inhibitory rate up to 82%, and IFN-γ had obviously synergistic action.

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.

Knockout of the tumor necrosis factor a receptor 1 gene can up-regulate erythropoietin receptor during myocardial ischemia-reperfusion injury in mice

Background Tumor necrosis factor a receptor 1 （TNFaR1） plays an important role in the signal pathway of apoptosis. The objective of this study was to investigate the effects of TNFaR1 knockout on the up-regulation of erythropoietin receptor （Epo-R） and the coordinated anti-apoptosis functions during myocardial ischemia-reperfusion injury in mice. Methods The ischemia-reperfusion injury model for cardiomyocytes was performed by ligating the left circumflex branch artery of TNFaR1 knockout （P55/） C17 B6 mice, as well as wild-type （P55^＋/^＋） C17 B6 mice. Triphenyltetrazolium chloride （TTC） staining was performed to observe the damaged area of the heart. TUNEL staining and DNA fragmentation were used to identify apoptosis. Mitochondrial Bcl-2 and Bax as well as expression of Epo-R and its downstream genes （Jak-2, stat-5, Akt, lkB-a, HIF-1a） were measured by Western blotting. The gene knockout mice were assigned into those undergoing the apoptosis surgical model group （KO group）, and those subjected to sham operation （KOs group）. Similarly, wild-type mice were either exposed to the surgical model （WT group） or subject to a sham operation （WTs group）. Results The myocardial damage ratio of the wild-type group after the operation was significantly higher than that of the knockout group, （50.5±6.4）% vs （36.9±6.9）%, P 〈0.01. Similarly, TUNEL positive ratio of the wild-type group was significantly higher than that of the knockout group, （63.1±5.6）% vs （42.1±4.7）%, P〈0.01. The gray value ratios of Epo-R, Jak-2, stat-5, Akt, IkB-a, HIF-1 and mitochondrial Bcl-2 in the KO group were significantly higher than those of the WT group, P 〈0.05; however, mitochondrial Bax was significantly lower than that of the WT group significantly （P 〈0.05）. Conclusions Using the ischemia-reperfusion injury model in mice, cardiomyocytes of TNFaR1 knockouts exhibited anti-apoptotic characteristics. This information could be used to coordinate the prevention of myocardial apoptosis by up-regulating and activating the Epo-R pathway.

The Lymphoblastoid Cell Lines of Recurrence Condyloma Acuminatum Patients Produce Lower Level of Tumor Necrosis Factor Stimulated with LPS

To study the mechanism of Condyloma acuminatum (CA) recurrence, and the association of CA recurrence with the ability of the host derived lymphoblastoid cell lines (LCL) stimulated by LPS to produce tumor necrosis factor (TNF), EBV-transformed B LCL were used as TNF producing cells The ability of LCL stimulated by LPS to produce TNF was measured by bioassay The results showed that the LCL from CA patients (including recurrent and non-recurrent CA patients) produced similar level of TNF stimulated by LPS to that of normal controls (29 54%±11 28% vs 34 31%±11 46%, P =0 1498) The LCL of CA recurrent patients produced significantly lower amount of TNF than that of non-recurrent CA patients (23 72%±7 41% vs 37 33%±11 10%, P =0 0032) Compared with the normal controls, CA recurrent patients showed a decreased ability to produce TNF (23 72%±7 41 vs 34 31%±11 46, P =0 0054), whereas CA non recurrent patients had the similar ability to the controls (37 33%±11 10 vs 34 31%±11 46, P =0 4914) It was concluded that the onset of CA was not relevant to the individual's ability to produce TNF But the recurrence of CA was associated with the ability to produce TNF It was also indicated that the TNF involved cellular immunity might play an important role in the clearance of the residual HPV by the host after treatment

Effect of tumor necrosis factor inhibitors on rheumatoid arthritis-induced peripheral neuropathy A cohort study

In this historical cohort study, 236 patients with primary rheumatoid arthritis were treated with the tumor necrosis factor inhibitors, etanercept or infliximab （n = 80）, or by conventional methods （n = 156）. Results revealed that 11 patients developed varying types of peripheral neuropathy at 1-2 years post-treatment （mean 16 months）. The incidence of peripheral neuropathy in the tumor necrosis factor inhibitors treatment group was 8.8% （7/80）, which was significantly higher than the conventional treatment group （2.6%; 4/156）. The relative risk of developing peripheral neuropathy in the tumor necrosis factor inhibitors treatment group was 3.41 （95% confidence interval： 1.03 11.31）. Comparison of the tumor necrosis factor inhibitors revealed that etanercept and infliximab had no significant difference in terms of inducing peripheral neuropathy. Experimental findings indicate that tumor necrosis factor inhibitors may increase the risk of peripheral neuropathy.

Tumor necrosis factor a accelerates Hep-2 cells proliferation by suppressing TRPP2 expression

TRPP2, a Ca^(2+)-permeable non-selective cation channel, has been shown to negatively regulate cell cycle, but the mechanism underlying this regulation is unknown. Tumor necrosis factor a(TNF-α) is a proinflammatory cytokine extensively involved in immune system regulation, cell proliferation and cell survival. However, the effects and mechanisms for the role of TNF-αin laryngeal cancer remain unclear. Here, we demonstrated using western blot analyses and intracellular Ca^(2+) concentration measurements that TNF-α treatment suppressed both TRPP2 expression and ATP-induced Ca^(2+) release in a laryngeal cancer cell line(Hep-2). Knockdown of TRPP2 by a specific siRNA significantly decreased ATP-induced Ca^(2+) release and abolished the effect of TNF-α on the ATP-induced Ca^(2+) release. TNF-α treatment also enhanced Hep-2 cell proliferation and growth, as determined using cell counting and flow cytometry cell cycle assays. Moreover, TNF-α treatment down-regulated phosphorylated protein kinase R-like endoplasmic reticulum kinase(p-PERK) and phosphorylated eukaryotic translation initiation factor(p-eIF2α)expression levels, without affecting PERK and eIF2 a expression levels in Hep-2 cells. We concluded that suppressing TRPP2 expression and TRPP2-mediated Ca^(2+) signaling may be one mechanism underlying TNF-α-enhanced Hep-2 cell proliferation.These results offer new insights into the mechanisms of TNF-α-mediated laryngeal cancer cell proliferation, and provide evidences showing a potential role of TNF-α in the development of laryngeal cancer.

Interleukin-1β,Tumor Necrosis Factor-α and Lipopolysaccharide Induce Expression of Monocyte Chemoattractant Protein-1 in Calf Aortic Smooth Muscle Cells

Summary: To investigate whether interleukin-1β(IL-1β), tumor necrosis factor-α (TNF-α) and lipopolysaccharide (LPS) induce expression of monocyte chemoattractant protein-1 (MCP-1 ) mRNA and protein in calf aortic smooth muscle cells(SMCs), calf aortic SMCs were cultured by a substrate-attached explant method. The cultured SMCs were used between the third to the fifth passage. After the cells became confluent, the SMCs were exposed to 2 ng/ml IL-1β, 20ng/ml TNF-1α and 100 ng/ml LPS respectively, and the total RNA of SMCs which were incubated for 4 h at 37℃ were extracted from the cells by using guanidinium isothiocyanate method. The expres- ion of MCP-1 mRNA in SMCs was detected by using dot blotting analysis using a probe of γ-32 P- end-labelled 35-mer oligonucleotide. After a 24-h incubation, the media conditioned by the cul- tured SMCs were collected. The MCP-1 protein content in the conditioned media was determined by using sandwich ELISA. The results were as follows: Dot blotting analysis showed that the cul- tured SMCs could express MCP-1 mRNA. After a 4-h exposure to IL-1β, TNF-α and LPS, the MCP-1 mRNA expression in SMCs was increased (3.6-fold, 2. 3-fold and 1. 6-fold, respectively). ELISA showed that the levels of MCP-1 protein in the conditioned media were also increased (2.9- fold, 1.7-fold and 1.1-fold, respectively). The results suggest that calf aortic SMCs could ex- press MCP-1 mRNA and protein. IL-1β and TNF-α can induce strong expression of MCP-1 mRNA and protein, and the former is more effective than the latter.