Tumor necrosis factor-α-induced protein 1 and immunity to hepatitis B virus

AIM: To compare the gene expression profile in a pair of HBV-infected twins. METHODS: The gene expression profile was compared in a pair of HBV-infected twins. RESULTS: The twins displayed different disease outcomes. One acquired natural immunity against HBV, whereas the other became a chronic HBV carrier. Eighty-eight and forty-six genes were found to be up- or down-regulated in their PBMCs, respectively. Tumor necrosis factor-alpha-induced protein 1 (TNF-alphaIP1) that expressed at a higher level in the HBV-immune twins was identified and four pairs of siblings with HBV immunity by RT-PCR. However, upon HBV core antigen stimulation, TNF-alphaIP1 was downregulated in PBMCs from subjects with immunity, whereas it was slightly upregulated in HBV carriers. Bioinformatics analysis revealed a K+ channel tetramerization domain in TNF-alphaIP1 that shares a significant homology with some human, mouse, and C elegan proteins. CONCLUSION: TNF-alphaIP1 may play a role in the innate immunity against HBV.     

Role of tumour necrosis factor-alpha and other cytokines in ischemia-reperfusion-induced injury in the heart

BACKGROUND:

Several investigations have implicated cytokines such as tumour necrosis factor-alpha (TNF-α), interleukin (IL)-1, IL-6, IL-8 and transforming growth factor-beta in the pathophysiology of cellular dysfunction in ischemia-reperfusion (I/R). Although an increase in the production of these cytokines has been detected after myocardial infarction and cardiopulmonary bypass surgery, their exact role and mechanisms for inducing cardiac dysfunction are poorly understood.

OBSERVATIONS:

TNF-α, transforming growth factor-beta, IL-1, IL-6 and IL-8 have frequently been studied in different cardiovascular diseases, including I/R injury in the heart. Low concentrations of TNF-α appear to exert cardioprotective effects, whereas high concentrations have been shown to produce deleterious actions in the heart. Some efforts have been made to explore the molecular mechanisms of cytokine actions; however, such information is insufficient to develop therapeutic strategies to combat their deleterious effects during the development of I/R injury in the heart.

CONCLUSIONS:

In addition to a time-dependent response, the conflicting effects of cytokines seem to depend on their concentrations used in different experimental studies. It is also likely that both the beneficial and pathophysiological actions of cytokines occur concomitantly. On the basis of the existing literature, it is suggested that different ways need to be found to modify the synthesis as well as the cardiodepressant actions of cytokines to improve the therapy of ischemic heart disease.     

预处理对肝脏再灌注损伤大鼠肝组织、血液中NO和ET的影响及意义

目的　探讨预处理对肝脏缺血再灌注损伤大鼠肝组织和血液中一氧化氮 (NO)和内皮素 (ET)含量的影响及意义。方法　建立肝脏 70 %缺血再灌注损伤大鼠模型 ,分为对照组、缺血组、缺血预处理组、L -精氨酸组(L - arg)、Nω-硝基 - N -精氨酸甲酯 (L - NAME)组 ,观察各组肝功能变化 ,检测肝组织和血清中 NO和 ET及透明质酸 (HA)水平。结果　预处理可减轻 NO水平的下降和血浆 ET的升高 ,防止肝功酶的升高 (P<0 .0 5 )。结论　预处理可诱导缺血再灌注损伤大鼠 NO产生增加、ET产生减少 ,进而改善其微循环 ,减少再灌注损伤。     

Pathological role of osteoclast costimulation in arthritis-induced bone loss

Abnormal T cell immune responses induce aberrant expression of inflammatory cytokines such as TNF-alpha, leading to osteoclastmediated bone erosion and osteoporosis in autoimmune arthritis. However, the mechanism underlying enhanced osteoclastogenesis in arthritis is not completely understood. Here we show that TNF-alpha contributes to inflammatory bone loss by enhancing the osteoclastogenic potential of osteoclast precursor cells through inducing paired Ig-like receptor-A (PIR-A), a costimulatory receptor for receptor activator of NF-kappaB (RANK). In fact, bone erosion and osteoporosis, but not inflammation, caused by aberrant TNF-alpha expression were ameliorated in mice deficient in Fc receptor common gamma subunit or beta(2)-microglobulin, in which the expression of PIR-As and PIR-A ligands is impaired, respectively. These results establish the pathological role of costimulatory receptors for RANK in bone loss in arthritis and may provide a molecular basis for the future therapy of inflammatory diseases.     

phytoestrogens/insoluble fibers and colonic estrogen receptor β: randomized,double-blind,placebo-controlled study

AIM:To assess the safety and effect of the supplementation of a patented blend of dietary phytoestrogens and insoluble fibers on estrogen receptor (ER)-β and biological parameters in sporadic colonic adenomas. METHODS:A randomized, double-blind placebo-controlled trial was performed. Patients scheduled to undergo surveillance colonoscopy for previous sporadic colonic adenomas were identified, and 60 eligible patients were randomized to placebo or active dietary intervention (ADI) twice a day, for 60 d before surveillance colonoscopy. ADI was a mixture of 175 mg milk thistle extract, 20 mg secoisolariciresinol and 750 mg oat fiber extract. ER-β and ER-α expression, apoptosis and proliferation (Ki-67 LI) were assessed in colon samples. RESULTS:No adverse event related to ADI was recorded. ADI administration showed a significant increases in ER-β protein (0.822 ± 0.08 vs 0.768 ± 0.10, P = 0.04) and a general trend to an increase in ER-β LI (39.222 ± 2.69vs 37.708 ± 5.31,P = 0.06), ER-β/ER-α LI ratio (6.564 ± 10.04 vs 2.437 ± 1.53, P = 0.06), terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (35.592 ± 14.97 vs 31.541 ± 11.54, P = 0.07) and Ki-67 (53.923 ± 20.91 vs 44.833 ± 10.38, P = 0.07) approximating statistical significance. A significant increase of ER-β protein (0.805 ± 0.13 vs 0.773 ± 0.13,P = 0.04), mRNA (2.278 ± 1.19vs 1.105 ± 1.07, P < 0.02) and LI (47.533 ± 15.47 vs 34.875 ± 16.67,P < 0.05) and a decrease of ER-α protein (0.423 ± 0.06vs 0.532 ± 0.11,P < 0.02) as well as a trend to increase of ER-β/ER-α protein in ADI vs placebo group were observed in patients without polyps (1.734 ± 0.20 vs 1.571 ± 0.42, P = 0.07). CONCLUSION:The role of ER-β on the control of apoptosis, and its amenability to dietary intervention, are supported in our study.     

异氟烷预处理对离体大鼠心肌缺血再灌注损伤的影响

目的:采用Langendorff离体心脏灌注模型,研究异氟烷预处理对离体大鼠心肌缺血再灌注损伤的影响。方法:24只SD大鼠随机分为4组,每组6只,分别为缺血再灌注损伤组(IR组)、异氟烷预处理1组(IsoP 1组)、异氟烷预处理2组(IsoP 2组)和异氟烷预处理3组(IsoP 3组)。监测复灌后心功能恢复情况、冠脉流出液中磷酸肌酸激酶(CK)、乳酸脱氨酶(LDH)的释放量和心肌存活面积的变化。结果:复灌期间3组IsoP心脏各对应时间点的LVEDP均显著低于对照组(P<0.05~<0.01);再灌注30 min时IsoP各组LVDP的恢复均高于IR组(P<0.05),IsoP3组±dp／dtmax在再灌注30 min时的恢复百分比均高于IR组(P<0.05),IsoP1组+dp／dt max高于IR组(P<0.05);复灌后异氟烷预处理组各时间点的CK、LDH释放量均低于IR组(P<0.01);IsoP2组、IsoP1组和IsoP3组心肌存活面积百分比均高于IR组(P<0.01);预处理各组之间比较无显著性差异(P>0.05)。结论:IsoP对大鼠离体缺血再灌注心肌有保护作用,可以显著减轻心肌细胞的损伤,改善心功能,增加心肌存活面积。     

Alterations of tumor necrosis factor-alpha and interleukin 6 production and activity of the reticuloendothelial system in experimental obstructive jaundice in rats

BackgroundImmunological changes are well recognised in obstructive jaundice. The aim of this study was to monitor plasma tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) levels in rats with obstructive jaundice.MethodsThe ability of splenocytes and peritoneal exudate cells (PEC) to produce these cytokines both spontaneously and on induction with lipopolysaccharide (LPS), was compared in rats with and without obstructive jaundice (OJ). The activity of the reticuloendothelial system (RES) was also measured.ResultsSerum cytokine levels in OJ rats were higher than in control rats. PEC cultures produced significantly more IL-6, compared with control rats, declining thereafter. TNF-α activity in the splenocyte cultures of OJ rats was also higher than in the control group. Pronounced differences were found in the ability to produce TNF-α by PEC, i.e., TNF-α production was much stronger on day 7 in OJ rats than in controls. On day 14 TNF-α production was much lower and the spontaneous response was equal to the LPS-induced one. On day 21 the cells of OJ rats partially regained the ability to produce TNF-α RES activity of OJ rats was significantly suppressed in the liver and spleen, whereas the phagocytic activity in the lungs was elevated.ConclusionWe have demonstrated that the immune reactivity of OJ rats, intially elevated, underwent subsequent depression. The study also revealed a major effect of the operation alone on the studied parameters.     

Pentoxifylline inhibits liver expression of tumor necrosis factor alpha mRNA following normothermic ischemia-reperfusion

Background: Pentoxifylline (PTX) has been shown to reduce hepatic injury after normothermic ischemia and reperfusion (I-R) in rat liver. Aim: The aim of this study was to evaluate the effects of PTX on liver expression of tumor necrosis factor alpha (TNFα) mRNA following normothermic liver I-R. Materials and methods: A segmental normothermic ischemia of the liver was induced in male Lewis rats by occluding the blood vessels including the bile duct to the median and left lateral lobes for 90 min. At the end of ischemia the nonischemic liver lobes were resected. Rats were divided into three groups: group 1, control Ringer lactate administration; group 2, PTX treatment; group 3, sham-operated control rats. PTX (50 mg/kg) was injected intravenously 30 min before and 60 min after induction of ischemia. Survival rates were compared and the serum activities of TNFα, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) were measured. Histology of the liver was assessed 6 h after reperfusion. Liver TNFα mRNA was assessed by PCR amplification at 0, 60, 120, and 210 min after reperfusion. Results: PTX treatment significantly increased 7 day survival (93.3%) compared with nontreated control rats (46.6%, p<0.007). The extent of liver necrosis and the release of liver enzymes were significantly decreased after PTX treatment. Serum activities of TNFα were significantly decreased and liver expression of TNFα mRNA was inhibited after PTX treatment. Conclusion: PTX protects the liver from ischemic injury and inhibits liver expression of TNFα mRNA.     

Detection of serum TNF-alpha,IFN-beta,IL-6 and IL-8 in patients with hepatitis B

AIM:To assess the possible roles of cytokines (TNF-alpha, IFN-beta, IL-6 and IL-8) in liver damage of hepatitis B.METHODS:The serum TNF-alpha, IFN-beta, IL-6 and IL-8 were detected by ELISA in 66 patients with hepatitis B and 20 healthy blood donors.RESULTS:TNF-alpha and IL-6 in all types of clinical hepatitis B were significantly higher than those in healthy blood donors (P < 0.05); meanwhile the levels of TNF-alpha, IFN-beta, IL-6 and IL-8 in the patients with fulminant hepatitis B were much higher than those in the patients with acute hepatitis B (P < 0.05); the level of TNF-alpha was positively correlated with the levels of IFN-beta, Il-6 and IL-8 in all types of hepatitis B (r(IFN) = 0.24,r(IL6) = 0.35,r(IL8) = 0.44) and the TNF-alpha, IFN-beta, IL-6 and IL-8 were positively correlated with serum bilirubin (P < 0.05). Dynamic changes of these cytokines were observed in the course of acute and fulminant hepatitis. The level of IFN-beta peaked in the initial period of acute hepatitis and early stage of hepatic coma in fulminant hepatitis; TNF-alpha, IL-6 and IL-8 increased with exacerbation, and reached a peak when the liver damage was most serious, then decreased when patient conditions were improved.CONCLUSION:The increased cytokines were related to the inflammation of liver cells and multiple factors may play certain roles in liver damage.     

Brain angiogenesis inhibitor 1 (BAI1) is a pattern recognition receptor that mediates macrophage binding and engulfment of Gram-negative bacteria

Bacterial recognition by host cells is essential for initiation of infection and the host response. Bacteria interact with host cells via multiple pattern recognition receptors that recognize microbial products or pathogen-associated molecular patterns. In response to this interaction, host cell signaling cascades are activated that lead to inflammatory responses and/or phagocytic clearance of attached bacteria. Brain angiogenesis inhibitor 1 (BAI1) is a receptor that recognizes apoptotic cells through its conserved type I thrombospondin repeats and triggers their engulfment through an ELMO1/Dock/Rac1 signaling module. Because thrombospondin repeats in other proteins have been shown to bind bacterial surface components, we hypothesized that BAI1 may also mediate the recognition and clearance of pathogenic bacteria. We found that preincubation of bacteria with recombinant soluble BAI1 ectodomain or knockdown of endogenous BAI1 in primary macrophages significantly reduced binding and internalization of the Gram-negative pathogen Salmonella typhimurium. Conversely, overexpression of BAI1 enhanced attachment and engulfment of Salmonella in macrophages and in heterologous nonphagocytic cells. Bacterial uptake is triggered by the BAI1-mediated activation of Rac through an ELMO/Dock-dependent mechanism, and inhibition of the BAI1/ELMO1 interaction prevents both Rac activation and bacterial uptake. Moreover, inhibition of ELMO1 or Rac function significantly impairs the proinflammatory response to infection. Finally, we show that BAI1 interacts with a variety of Gram-negative, but not Gram-positive, bacteria through recognition of their surface lipopolysaccharide. Together these findings identify BAI1 as a pattern recognition receptor that mediates nonopsonic phagocytosis of Gram-negative bacteria by macrophages and directly affects the host response to infection.     

异氟醚预处理对心肌缺血再灌注损伤的保护作用

目的:观察异氟醚预处理对体外循环心内直视手术心肌的保护作用。方法:20例瓣膜置换术患者(ASA 2～3 级),随机分为预处理组(Ⅰ组)和对照组(C组)。分别于麻醉后(T_1),主动脉开放后15分钟(T_2)、2小时(T_3)、24小时(T_4)时间点取血样,检测血清CGRP、ET、cTnI;另于术前、术后第1、3天记录同步12导联心电图.测定其QTd和 QTcd。结果:主动脉开放后,CGRP含量在两组患者24小时之内都有显著增加(P<0.01),T_2时,预处理组的CGRP水平明显高于对照组的(P<0.05);ET在T_2时两组都有显著上升(P<0.01),但预处理组的上升幅度明显低于对照组(P<0.05);T3、T4时,对照组cTnI水平显著高于预处理组;术后两组QTd和 QTcd显著增加(P<0.01),其中对照组的增加较多,且第1天明显多于预处理组(P<0.05);结论:异氟醚预处理能减少心肌的缺血再灌注损伤,降低术后心律失常发生率,有利体外循环后心功能恢复。     

Hypoxia inducible factor-1α mediates protective effects of ischemic preconditioning on ECV-304 endothelial cells

AIM: To investigate whether hypoxia inducible factor-1α (HIF-1α) is linked to the protective effects of ischemic preconditioning (IP) on sinusoidal endothelial cells against ischemia/reperfusion injury. METHODS: Sinusoidal endothelial cell lines ECV-304 were cultured and divided into four groups: control group, cells were cultured in complete DMEM medium; cold anoxia/warm reoxygenation (A/R) group, cells were preserved in a 4℃ UW solution in a mixture of 95% N2 and 5% CO2 for 24 h; anoxia-preconditioning (APC) group, cells were treated with 4 cycles of short anoxia and reoxygenation before prolonged anoxia- preconditioning treatment; and anoxia-preconditioning and hypoxia inducible factor-1α (HIF-1α) inhibitor (I-HIF-1) group, cells were pretreated with 5 μm of HIF-1α inhibitor NS398 in DMEM medium before subjected to the same treatment as group APC. After the anoxia treatment, each group was reoxygenated in a mixture of 95% air and 5% CO2 incubator for 6 h. Cytoprotections were evaluated by cell viabilities from Trypan blue, lactate dehydrogenase (LDH) release rates, and intracellular cell adhesion molecule-1 (ICAM-1) expressions. Expressions of HIF-1α mRNA and HIF-1α protein from each group were determined by the RT-PCR method and Western blotting, respectively. RESULTS: Ischemia preconditioning increased cell viability, and reduced LDH release and ICAM-1 expressions. Ischemia preconditioning also upregulated the HIF-1α mRNA level and HIF-1α protein expression. However, all of these changes were reversed by HIF-1α inhibitor NS398.CONCLUSION: Ischemia preconditioning effectively inhibited cold hypoxia/warm reoxygenation injury to endothelial cells, and the authors showed for the first time HIF-1α is causally linked to the protective effects of ischemic preconditioning on endothelial cells.     

肢体缺血预处理和后处理对脑缺血的保护作用及其机制

远隔缺血预处理和缺血后处理是减轻缺血再灌注损伤的2种新方法。近年来的研究显示,其对脑缺血也具有显著的保护作用。在适当时机给予适当强度的远隔缺血预处理或后处理可诱导脑组织缺血耐受,进而产生神经保护作用。肢体缺血预处理和后处理操作简单,临床应用价值较高。文章对肢体缺血预处理和后处理对脑缺血的保护作用进行了综述。     

The endothelin receptor antagonist decreases ischemia/reperfusion-induced tumor necrosis factor production in isolated rat hearts

Previous studies have shown that endothelin-1 (ET-1) may play a pathophysiological role in myocardial ischemia/reperfusion injury. In the present study, BMS-182874 significantly improved the recovery of cardiac function and reduced the release of CK during reperfusion after ischemia and the content of tumor necrosis factor (TNF-alpha) in myocardial tissues. BMS-182874 also reduced myocardial injury and the increased level of TNF-alpha by exogenous ET-1. These results suggest that the cardioprotective effects of the ET receptor antagonist may be related to inhibition of TNF-alpha production.     

Changes in cytokine profile pre- and post-immunosuppression in acquired aplastic anemia

Cytokine expression assessed by flow cytometry in 53 acquired aplastic anemia patients before and after combined immunosuppression (EBMT WPSAA protocols) showed that CD3⁺ marrow cells containing TNF-α, IFN-γ and IL4 were similar in subjects with disease at onset (DO) and responsive to treatment who had more CD3⁺/TNF-α⁺ and CD 3⁺/IFN-γ⁺ cells than normal controls. In vitro block of TNF-α and/or IFN-γ significantly increased BFU-e over baseline in 28 patients. In responsive to treatment patients only TNF-α block significantly incremented colonies over normal controls. Absolute marrow CD3⁺/TNF-α⁺ and CD3⁺/IFN-γ⁺ cells prospectively tested in a group of 21 subjects declined significantly more in Responders than in Non Responders to immunosuppression at Response Evaluation Time respect to Diagnosis. Both in Responders and in Non Responders these cells remained higher than in normal controls. This study suggests that immunosuppression does not fully clear excess TNF-α and IFN-γ from marrow of patients with good outcome and raises the hypothesis that additional cytokine blockade might be useful in immunosuppression for acquired aplastic anemia.     

超速起搏预适应的延迟保护作用与环氧化酶2表达的关系

目的观察在超速心室起搏(VOP)预适应延迟保护阶段环氧化酶2(COX-2)的表达水平,从而探讨预适应延迟保护作用机制与COX-2的关系。方法健康的新西兰雄兔24只,随机分为3组,单纯结扎组、起搏组、起搏+放线菌素D组,每组8只,制作超速起搏预适应和缺血/再灌注动物模型,检测肌酸激酶(CK)、CK同工酶(CK-MB)的变化,动态描记再灌注时心电图变化,免疫组化染色检测COX-2抗原。结果缺血后起搏组CK、CK-MB的水平[(1492±474)IU/L和(614±182)IU/L]在再灌注时低于单纯结扎组[(2625±423)IU/L和(1332±178)IU/L]及起搏+放线菌素D组[(2071±390)IU/L和(1095±183)IU/L](P<0.01);单纯结扎组再灌注过程中共有5只(62.5%)发生心律失常,起搏+放线菌素D组也有4只(50%),而起搏组中无心律失常发生,起搏组和单纯结扎组中之间差异具有统计学意义(P<0.05),起搏组中COX-2的阳性表达程度明显高于其他两组。结论超速起搏预适应可以模拟缺血预适应,其延迟保护作用可能与COX-2的表达增加密切相关。     

Modulation of TNF-alpha-converting enzyme by the spike protein of SARS-CoV and ACE2 induces TNF-alpha production and facilitates viral entry

Severe acute respiratory syndrome coronavirus (SARS-CoV) is a high-risk infectious pathogen. In the proposed model of respiratory failure, SARS-CoV down-regulates its receptor, angiotensin-converting enzyme 2 (ACE2), but the mechanism involved is unknown. We found that the spike protein of SARS-CoV (SARS-S) induced TNF-alpha-converting enzyme (TACE)-dependent shedding of the ACE2 ectodomain. The modulation of TACE activity by SARS-S depended on the cytoplasmic domain of ACE2, because deletion mutants of ACE2 lacking the carboxyl-terminal region did not induce ACE2 shedding or TNF-alpha production. In contrast, the spike protein of HNL63-CoV (NL63-S), a CoV that uses ACE2 as a receptor and mainly induces the common cold, caused neither of these cellular responses. Intriguingly, viral infection, judged by real-time RT-PCR analysis of SARS-CoV mRNA expression, was significantly attenuated by deletion of the cytoplasmic tail of ACE2 or knock-down of TACE expression by siRNA. These data suggest that cellular signals triggered by the interaction of SARS-CoV with ACE2 are positively involved in viral entry but lead to tissue damage. These findings may lead to the development of anti-SARS-CoV agents.     

丙泊酚预处理与缺血预处理保护大鼠体外心脏缺血再灌注损伤作用的比较

目的:以缺血预处理(IPC)为标准观察丙泊酚预处理对大鼠体外心脏再灌注损伤的保护作用并探索其可能机制。方法:建立大鼠体外心脏Langendorff灌流模型并随机分为对照组(A组, n=8)、丙泊酚预处理组(B组,n=6)、IPC组(C组,n=6)及5 羟癸酸(5 HD)对照组(D组,n=8)、5 HD加丙泊酚预处理组(E组,n=6)、5 HD加 IPC组(F组,n=7)共6组。连续记录各组心脏血流动力学指标及冠状动脉流量变化,进行再灌注性心律失常评分,并计算心脏梗死面积。结果:B、C、E组血流动力学指标、冠状动脉流量、心律失常评分、梗死面积显著优于A组,以C组最显著(P<0.01或0.05),而D、F组与A组比较差异无统计学意义。结论:丙泊酚预处理与 IPC均可改善体外大鼠心脏再灌注所致的血流动力学紊乱、冠状动脉循环受损及再灌注性心律失常的发生,并缩小心脏梗死面积,但丙泊酚上述保护效应较 IPC弱。阻滞线粒体 KATP通道开放对丙泊酚预处理作用无影响,推测该通道与其保护效应无关。     

Expression of macrophage inflammatory protein-1α in Kupffer cells following liver ischemia or reperfusion injury in rats

AIM: To explore the expression of macrophage inflammatory protein-1alpha (MIP-1alpha) in Kupffer cells (KCs) following liver ischemia/reperfusion injury IRI in rats. METHODS: Forty male SD rats were divided randomly into five groups. A model of partial warm ischemia/reperfusion injury in the rat liver was established. KCs were isolated and incubated one hour, six hours, 12 h, and 24 h after the reperfusion. Tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta) in the supernatants were measured by ELISA. MIP-1alpha in KCs was detected by immunocytochemical and RT-PCR. RESULTS: No or few MIP-1alpha protein and mRNA were expressed in the KCs of the control group. Its expression in the IRI group had a significant increase after the reperfusion (P < 0.05), which was contrary to the control group. CONCLUSION: The active behavior of the MIP-1alpha gene in KCs following liver ischemia/reperfusion injury is assumed to be one of the major causes for the hepatic ischemia/reperfusion injury.