Objective To investigate the protective effects of antitumor necrosis factor-α antibody （TNF-αAb） on lung injury after cardiopulmonary bypass （CPB） and their mechanisms. Methods Forty healthy New Zealand white rabbits，weighting 2.0-2.5 kg，male or female，were randomly divided into 4 groups with 10 rabbits in each group. In groupⅠ，the rabbits received CPB and pulmonary arterial perfusion. In group Ⅱ，the rabbits received CPB and pulmonary arterial perfusion with TNF-αAb. In group Ⅲ，the rabbits received CPB only. In group Ⅳ，the rabbits only received sham surgery. Neutrophils count，TNF-α and malondialdehyde （MDA） concentrations of the blood samples from the left and right atrium as well as oxygenation index were examined before and after CPB in the 4 groups. Pathological and ultrastructural changes of the lung tissues were observed under light and electron microscopes. Lung water content，TNF-α mRNA and apoptoticindex of the lung tissues were measured at different time points. Results Compared with group Ⅳ，after CPB，the rabbitsin group Ⅰ to group Ⅲ showed significantly higher blood levels of neutrophils count，TNF-α and MDA（P＜0.05），higherTNF-α mRNA expression，apoptosis index and water content of the lung tissues （P＜0.05），and significantly lower oxyg-enation index （P＜0.05） as well as considerable pathomorphological changes in the lung tissues. Compared with group Ⅱ，after CPB，the rabbits in groups Ⅰ and Ⅲ had significantly higher blood concentrations of TNF-α （5 minutes after aortic declamping，220.43±16.44 pg/ml vs.185.27±11.78 pg/ml，P＜0.05；249.99±14.09 pg/ml vs.185.27±11.78 pg/ml，P＜0.05），significantly higher apoptosis index （at the time of CPB termination，60.7‰±13.09‰ vs. 37.9‰±7.78‰，P＜0.05；59.6‰±7.74‰ vs. 37.9‰±7.78‰，P＜0.05），significantly higher blood levels of neutrophils count and MDA （P＜0.05），significantly higher TNF-α mRNA expression and water content of the lung tissues （P＜0.05），and significantly loweroxygenation index （P＜0.05） as well as considerable pathomorphological changes in the lung tissues. Compared with groupⅠ，rabbits in group Ⅲ had significantly higher above parameters （P＜0.05） but lower oxygenation index （P＜0.05） only at 30 minutes after the start of CPB. Conclusion Pulmonary artery perfusion with TNF-αAb can significantly attenuate inflammatory lung injury and apoptosis of the lung tissues during CPB.
Objective To investigate the effects of expression of TNFα mRNA on glucose uptake in both the liver and skeletal muscle after endotoxemia. Methods In the mice with intraperitoneal injection of lipopolysaccharide (LPS), the changes of TNFα level of plasma and uptake of 2-deoxyglucose (2-DG) in the isolated soleus muscle and hepatic tissues were determined, then the reinstatement of glucose uptake by injecting TNF-McAb for 3 days was also observed. In addition, changes of TNFα mRNA expression of liver were evaluated. Results The expression of TNFα mRNA in the liver showed markedly increased in the first 3 hours post endotoxemia and remaind high for 3 days, and the plasma TNFα level paralleled with TNFα mRNA expression of liver also was elevated. The basal uptake of 2-DG both in muscle and liver were markedly increased, but the stimulated 2-DG uptake with insulin was greatly reduced as compared with the control. In addition, these abnormalities of 2-DG uptake can be partially corrected by neutralization of the circulatory TNFα by administration of TNF-McAb. Conclusion The disorders of glucose uptake of the liver and the muscle due to the overexpression of TNFα mRNA and elevated circulatory TNFα level may be the mechanism of insulin resistance after endotoxemia.
【Abstract】 Objective To investigate the expression and significance of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptors in pancreatic cancer. Methods Thirty-two samples of pancreatic cancer tissue were collected from year 2002 to 2004. All of them were verified by histopathology and there were 9 cases of well-differentiated, 12 of moderately differentiated, and 11 of poorly differentiated, in which 12 cases were in the stage of Ⅰor Ⅱand 20 in the stage of Ⅲ or Ⅳ according to the TNM staging method. Eighteen normal pancreatic tissues were used as control group. The expressions of TRAIL receptors (death receptor 4, death receptor 5, decoy receptor 4 and decoy receptor 5) mRNA were assayed by semi-quantitive reverse transcription polymerase chain reaction (RT-PCR) in the pancreatic cancer tissues and the normal pancreatic tissues. Results The expressions of death receptor 4 (DR4) and death receptor 5 (DR5) were detected in all the pancreatic cancer tissues and the normal pancreatic tissues and the levels of DR4 and DR5 were significantly higher than those of the normal pancreatic tissues (P＜0.01). Decoy receptor 1 (DcR1) and decoy receptor 2 (DcR2) were also expressed in normal pancreatic tissues, whereas DcR1 and DcR2 were only expressed in 18 and 20 pancreatic cancer tissues, respectively. However, there were no significant difference of the expression of DcR1 and DcR2 between the pancreatic cancer tissues and the normal pancreatic tissues （Pgt;0.05）. The expression level of DR5 in pancreatic cancer tissue was correlated with tumor differentiation and clinical stage, and the levels in stage Ⅲ and stage Ⅳwere significantly lower than those of stageⅠand stageⅡ(P＜0.05). The expressions of DR4, DcR1 and DcR2 were not correlated with tumor differentiation and clinical stage (Pgt;0.05). Conclusion ①The expression of TRAIL receptors in pancreatic cancer tissues is prevalent, but the types of receptors expressed in different tissues were also different. High expression of death receptors may play an important role in TRAIL recptors regulated pancreatic cancer apoptosis. ②The expression of DR5 is correlated with the differentiation degree of pancreatic cancer cell and clinical stage of tumor. The expressions of DR4, DcR1 and DcR2 should not be considered as related indexes of differentiation degree or clinical stage of pancreatic cancer.
ObjectiveTo investigate the effects of transforming growth factor-β (TGF-β) in choroidal neovascularization (CNV) induced by laser in mice. Methods Eighty male C57BL/6J mice at the age of 6-8 weeks old were randomly divided into the normal control, photocoagulation model, photocoagulation with phosphate buffered saline (PBS control group) and photocoagulation with TGF-β receptor inhibitor groups (TGF-β receptor inhibitor group), twenty mice of each group. Fundus argon laser photocoagulation was performed in the photocoagulation model group, PBS control group and TGF-β receptor inhibitor group to induce CNV. One week, two, three and four weeks after the laser procedure, fundus fluorescein angiography (FFA) was carried out in the normal control or photocoagulation model groups to observe CNV formation dynamically. Western blot was used to analyze the expressions of TGF-β in the retina from the mice of normal control or photocoagulation model groups, and VEGF or TNF-α in the retina of normal control, PBS control or TGF-β receptor inhibitor groups. The CNV areas of each group were evaluated by using fluorescein stain on retinal pigment epithelium (RPE)/choroid flat mounts after two weeks of photocoagulation. ResultsThe FFA results showed the retinal vessels centered on the optic disc and arranged radially, while the choroidal vascular present network distribution in the normal control mice. Significant leakage of fluorescein showed discoid strong fluorophore in photocoagulation sites of retina at one week after photocoagulation. The quantitative analysis results of Western blot demonstrated that the TGF-β protein expression levels in retina of photocoagulation model mice gradually increased with time passing. The protein expression levels of TGF-β were significant differences in the photocoagulation model group comparing with the normal control group (F=13.042, P < 0.05). The protein expression levels of TNF-α (F=14.721, 17.509) and VEGF (F=18.890, 11.251) increased significantly in retina of PBS control or TGF-β receptor inhibitor groups when compared with that of normal control group at one week, two, three and four weeks after photocoagulation, and the differences were both statistically significant (P < 0.05). Compared with PBS control group, the protein levels of TNF-α and VEGF in retina from TGF-β receptor inhibitor group were significantly reduced, the differences was statistically significant (F=21.321, 16.160, P < 0.05). Two weeks after laser photocoagulation, a distinct reduction in CNV lesion size in the TGF-β receptor inhibitor group mice when compared to PBS or normal control groups, the differences was statically significant (F=4.482, P < 0.05). ConclusionTGF-β may promote CNV formation by up-regulating both TNF-α and VEGF protein expressions, the application of its specific inhibitor is able to reduce CNV progression.
目的研究依达拉奉影响肝脏缺血再灌注过程中TNF-α的表达情况，探讨依达拉奉对肝脏缺血再灌注损伤的逆转作用。 方法将80只Wistar大鼠编号，根据计算机产生随机数字，前40为一组，后40为一组，分为实验组和对照组2组，建立常温下部分肝缺血再灌注损伤动物模型。 在肝脏缺血再灌注损伤开始前1 h和开始时对实验组大鼠给予依达拉奉注射液10 ml，对照组则给予同等容量的生理盐水。分别于再灌注后0、1、2及4 h测定肝脏脂质过氧化物酶（LPO）和肝脏谷草转氨酶(AST) 浓度； 应用RT-PCR法检测肝组织TNF-α mRNA含量，并测定肝组织和血清中TNF-α水平； 应用TUNEL染色法检测缺血肝组织的细胞凋亡情况。结果再灌注后1、2及4 h，实验组大鼠肝脏LPO及AST浓度均明显低于对照组（Plt;0.001）； 实验组再灌注后1 h时肝组织TNF-α mRNA表达量、肝组织和血清TNF-α含量均明显升高且达峰值，但均明显低于对照组（Plt;0.05）； 再灌注后各时相实验组肝细胞凋亡率明显升高，但均明显低于对照组（Plt;0.05）。 结论依达拉奉能抑制氧化应激反应，从而降低肝缺血再灌注损伤； 并显著减少炎性细胞因子TNF-α的产生，抑制炎性反应的发生，减少肝细胞的凋亡。
ObjectiveTo investigate the expression of tumor necrosis factor-α (TNF-α) in prostate cancer tissue and explore its relations with tumor angiogenesis. MethodsThe expression of TNF-α and CD105 were detected with two-step immunohistochemical staining technique in 20 cases of benign prostatic hyperplasia and 50 cases of prostate cancer between January 2010 and January 2012, and microvessel density (MVD) marked with CD105 was also measured. ResultsThe expressions of TNF-α and CD105 were higher in prostate cancer (41.72±8.67, 20.15±2.67) than those in benign prostatic hyperplasia (21.01±3.85, 4.34±1.67) (t'=13.990, P<0.001; t'=29.771, P<0.001). TNF-α and MVD were not correlated with age and size of tumor, but were positively correlated with tumor differentiation degree (rs=0.847, P<0.001; rs=0.776, P<0.001) and negatively correlated with clinical grades (rs=-0.769, P<0.001; rs=-0.842, P<0.001). ConclusionThe result indicates that over expression of TNF-α exists in prostate cancer. It may play an important role in the anginogenesis and carcinogenesis of prostate cancer.
Objective To investigate the mechanism of the resistance of pancreatic cancer cells to tumor necrosis factor related apoptosis inducing ligand (TRAIL)mediated apoptosis. MethodsThe expression of TRAIL receptor-4 (TRAIL-R4) in normal pancreas tissue and pancreatic cancer was analyzed by using Northern blotting, Western blotting and immunohistochemistry.ResultsTRAIL-R4 mRNA and protein were expressed at moderate to high levels in human pancreatic cancer, but demonstrated weak to negative in the normal pancreas. Moreover, pancreatic cancer cells showed b TRAIL-R4 immunostaining throughout the tumor mass. Conclusion TRAIL-R4 levels are significantly different in pancreatic cancer in comparison to the normal pancreas. These findings give new insights into the resistance mechanisms of pancreatic cancer cells towards TRAILmediated apoptosis.
目的:研究离体肝脏缺血再灌注期间丝裂原活化蛋白激酶(mitogen activated protein kinase,p38MAPK)信号转导途径对肿瘤坏死因子α (tumor necrosis factor α,TNFα )mRNA表达的影响。方法:建立兔离体肝脏缺血再灌注模型,对照组(n=12)灌注液中不加特异性p38MAPK抑制剂SB202190,抑制组(n=12)灌注液中加入SB202190(浓度为3μmol/L)。分别于肝脏离体前,冷保存末,再灌注10min、30min、60min及120min时获取离体肝组织标本。应用Western-blot法及免疫沉淀法检测离体肝组织中p38MAPK表达的水平及活性,RT-PCR法检测TNF-α-mRNA表达水平。结果:对照组p38MAPK活性在冷保存末及再灌注10min、30min、60min均较离体前和再灌注120min显著升高(Plt;0.01),也显著高于同时相点的抑制组(Plt;0.01);抑制组p38MAPK活性在组内各时相点的变化无显著性差异(Pgt;0.05)。两组肝脏于离体前、冷保存末及再灌注10min及30min,肝组织中仅有少量TNF-α mRNA表达,组间及组内比较无显著性差异(Pgt;0.05);至再灌注60min及120min,对照组TNF-α mRNA的表达水平显著性高于组内其它时相点(Plt;0.01),而抑制组虽然也显著高于组内其它时相点(Plt;0.05),但却显著性低于同时相点对照组的表达水平(Plt;0.01)。离体再灌注期间供肝组织中p38MAPK活性与供肝组织内TNF-α mRNA的表达水平呈显著性正相关(r=0.996,Plt;0.01)。结论:p38MAPK对TNF-α生成的调节作用层次可能在转录水平,提示p38MAPK信号转导途径对TNF-α mRNA的调节可能是导致离体肝脏缺血再灌注损伤的重要机制之一。