跨膜型肿瘤坏死因子-α对宫颈癌细胞毒性效应的研究

目的 观察跨膜型肿瘤坏死因子-α （TM-TNF-α）对人宫颈癌HeLa细胞的效应,并探讨其与人宫颈癌HeLa细胞死亡结构域沉寂子（SODD）表达的关系.方法 应用免疫细胞化学法检测增殖细胞核抗原（PCNA）表达;应用反转录-聚合酶链反应技术检测未经处理的和经TM-TNF-α作用后的人宫颈癌HeLa细胞SODD的表达情况及TM-TNF-α对其影响.结果 未经处理的人宫颈癌HeLa细胞PCNA阳性率为80.3％（155/193）,经TM-TNF-α作用后的人宫颈癌HeLa细胞PCNA阻性率降为46.7％（85/182）,两者比较差异有统计学意义（P＜0.05）.人宫颈癌HeLa细胞的聚合酶链反应循环次数设定为28次,所获扩增产物经2％琼脂糖凝胶电泳,经TM-TNF-α作用后的人宫颈癌HeLa细胞和未经处理的人宫颈癌HeLa细胞灰度值分别为1.377±0.170和0.815±0.040,两者比较差异有统计学意义（P＜0.05）.结论 TM-TNF-α可通过上调SODD的表达来增强其对人宫颈癌HeLa细胞的体外杀伤效应.     

肿瘤坏死因子-α基因多态性与早产

肿瘤坏死因子-α是一种具有多种生物学活性的多功能细胞因子,其编码基因具有多态性,这些多态性可以从转录水平上影响肿瘤坏死因子-α的表达,并与个体对疾病的易感性、发展、预后相关。研究表明早产患者羊水、血清、组织中肿瘤坏死因子-α表达量显著升高。该文就肿瘤坏死因子-α基因多态性与早产的相关性作以综述。     

Induction of tumor necrosis factor production and antitumor effect by cabbage extract

The effect of cabbage extract on the production of tumor necrosis factor and its implication in the antitumor effect were examined in vitro and in vivo. Cabbage extract stimulated the production of tumor necrosis factor by rat spleen cells and showed cytotoxic activity in a rat ascites hepatoma cell line (AH109A) when hepatoma cells were cultured with cabbage-stimulated spleen cells. When the extract was adminstered orally to AH109A-bearing rats in combination with lipopolysaccharide injection, the hepatoma weights were reduced to one-half of the vehicle control. The cytotoxic activity of tumor-infiltrating macrophages was induced by simultaneous treatment with cabbage extract and lipopolysaccharide. These results indicate that cabbage extract contains macrophage-stimulating component(s) and can implement the antitumor effect by stimulating the cytotoxicity of tumor-infiltrating macrophages.     

肿瘤坏死因子在病毒性肝炎中的临床研究

近年来,细胞因子在病毒性肝炎发病机制中的作用越来越受到人们的重视.笔者对213例各型病毒性肝炎患者进行了血清肿瘤坏死因子(TNF-α)水平检验,以探讨其在病毒性肝炎中的作用.     

Glutamine attenuates tumor necrosis factor-alpha release and enhances heat shock protein 72 in human peripheral blood mononuclear cells

OBJECTIVE: Overexpression of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) can contribute to multiple organ dysfunction syndrome and septic shock in critically ill patients. We previously found that glutamine (GLN) can attenuate cytokine expression, induce heat shock protein 72 (HSP 72), and protect against endotoxin-induced mortality and organ injury in an in vivo rat model. However, data on the effect of GLN on direct attenuation of cytokine release and HSP 72 expression in human peripheral blood polymorphonuclear cells (PBMCs) is lacking.METHODS: In this study, we assessed the effect of GLN on TNF-alpha and HSP 72 expression in human PBMCs. After treating with various doses of GLN, human PBMCs were stimulated with lipopolysaccharide (LPS). TNF-alpha release was analyzed via enzyme-linked immunosorbent assay and HSP 72 via western blot. RESULTS: GLN at doses greater than 4 mM decreased TNF-alpha release at 4 and 24 h after LPS stimulation. Sublethal heating of PBMCs before LPS also markedly decreased TNF-alpha after LPS. Doses of GLN greater than 2 to 4 mM led to an increase in HSP 72 expression after LPS. CONCLUSION: These results indicate that GLN, which may improve outcomes in critically ill patients, can directly attenuate pro-inflammatory cytokine release in PBMCs. This effect may be related to enhanced HSP 72 expression.     

肿瘤坏死因子-a及其Ⅱ型受体基因多态性与矽肺

目的探讨肿瘤坏死因子-a(TNF-a)及其Ⅱ型受体(TNFRⅡ)基因多态性在矽肺发病遗传易感性中的作用及其与二氧化硅暴露的交互作用.方法选择259例矽肺患者和341例矽尘接触者(对照)为研究对象,对其职业史、尘肺病史、既往病史等进行问卷调查;拍摄其高仟伏X射线后前位胸片,根据尘肺病诊断标准进行诊断和分期;采集每个研究对象的外周静脉血,应用聚合酶链反应-限制性片断长度多态性(PCR-RFLP)技术检测其TNF-a及TNFRⅡ基因多态性.结果在成组或11配对分析中,矽肺患者和矽尘接触者两组间TNF-a基因-308位点G/A+A/A基因型和TNFRⅡ196位点T/G+G/G基因型分布频率的差异均无统计学意义(P＞0.05).当接尘工龄＜15年时,G/A+A/A基因型携带者发生矽肺的危险性是G/G基因型的6.74倍,95%CI1.01～44.99.结论TNF-α和TNFRⅡ基因多态性在汉族人群矽肺发病的遗传易感性中不起主要作用.TNF-α基因-308位点基因多态性在矽肺发病过程中与接尘工龄存在交互作用,当累积接尘量较低时,G/A+A/A基因型携带者发生矽肺的危险性较G/G基因型明显增加.     

脱氧雪腐镰刀菌烯醇对体外培养人外周血单核细胞增殖及肿瘤坏死 …

为探讨我国恶性肿瘤高发区居民饮食中的优势污染霉菌毒素－脱氧雪腐镰刀菌烯醇（ＤＯＮ）对人体免疫机能的影响，分别以流式细胞光度术（ＦＣＭ）、细胞计数、甲基噻唑基四唑（ＭＴＴ）比色、双抗体夹心ＥＬＩＳＡ方法对ＤＯＮ作用后人外周血单核细胞（ＨＰＢＭ）增殖和肿瘤坏死因子－α（ＴＮＦ－α）分泌情况进行了研究。ＦＣＭ检测结果表明，ＨＰＢＭ经ＰＨＡ预刺激４８ｈ后，低浓度ＤＯＮ（５０￣５００ｎｇ／ｍｌ）处理６ｈ的细     

Soluble tumor necrosis factor-alpha receptor type 1 during selenium supplementation in psoriasis patients

OBJECTIVE: Tumor necrosis factor-alpha (TNF-alpha) and its receptors play important roles in the induction and maintenance of psoriatic lesions. Selenium (Se), a trace element with immunomodulatory properties, is usually decreased in psoriasis patients. We examined the influence of Se supplementation on soluble TNF-alpha receptor type 1 (sTNF-R1) and topical treatment in psoriasis patients. METHODS: The study was conducted in between January and June 2002. Twenty-two inpatients with active plaque psoriasis received topical treatment with 5% salicylic acid ointment, 0.1% to 0.3% dithranol ointment, and 200 microg daily of Se as selenomethionine (SeMet; n = 11, group 1) or placebo (n = 11, group 2) for 4 wk. Psoriasis Area and Severity Index (PASI) score and Se and sTNF-R1 concentrations were assessed at baseline and every 2 wk. Control sera were obtained from 10 healthy subjects. For statistical analysis, parametric tests were used, and the level of significance was set at P = 0.05. RESULTS: The baseline sTNF-R1 levels were 1.87 +/- 0.58 ng/mL (1.98 +/- 0.44 ng/mL in group 1 and 1.75 +/- 0.69 ng/mL in group 2, P = 0.34) in psoriasis patients and 1.65 +/- 0.25 ng/mL in control subjects (P = 0.17); baseline Se concentrations were 48.31 +/- 13.20 microg/L (48.31 +/- 13.20 microg/L in group 1 and 50.35 +/- 13.49 microg/L in group 2, P = 0.41) in psoriasis patients and 58.30 +/- 17.21 microg/L in control subjects (P = 0.05). A positive correlation between PASI and sTNF-R1 was noticed (r = 0.36, P = 0.04; r = 0.51 in group 1 and r = 0.18 in group 2). After 4 wk, almost complete remission of skin lesions was achieved in both groups, but the PASI score was higher in group 1 than in group 2 (4.30 +/- 3.92 and 1.67 +/- 1.17, respectively; P < 0.05). TNF-R1 levels were 1.81 +/- 0.42 ng/mL in group 1 and 1.33 +/- 0.40 ng/mL in group 2 (P = 0.01), and the correlation between PASI score and TNF-R1 level became inverse (r = -0.24 in group 1 and r = -0.59 in group 2). Se concentrations were 107.51 +/- 18.08 microg/L in group 1 and 56.83 +/- 15.32 microg/L in group 2 (P < 0.01). CONCLUSIONS: Increased level of sTNF-R1 may be an indicator of active psoriasis. Supplementation with selenomethionine was ineffective as adjuvant treatment in plaque psoriasis and may contribute to the maintenance of elevated TNF-R1 concentration in psoriasis patients despite the remission of skin lesions.     

Docosahexaenoic acid and vitamin E can reduce human monocytic U937 cell apoptosis induced by tumor necrosis factor

The effects of polyunsaturated fatty acids and vitamin E on tumor necrosis factor (TNF)-induced apoptosis of human monocytic U937 cells was explored to assess to what extent these nutrients could attenuate apoptosis. Preincubation of U937 cells with arachidonic acid for 24 h did not affect TNF-induced apoptosis. Eicosapentaenoic acid slightly but significantly reduced the proportion of apoptotic cells only when apoptosis was induced by TNF without cycloheximide (CHI). In contrast, preincubation with docosahexaenoic acid (DHA) greatly (40 approximately 70%) attenuated apoptosis induced by stimulation with either TNF or TNF + CHI for 3 h. The inhibition of apoptosis was accompanied by enrichment of DHA in membrane phospholipids, indicating that DHA probably exerted its inhibitory activity after being incorporated into the phospholipids. Vitamin E also played a role as a partial inhibitor of apoptosis 3 h after TNF addition. This vitamin could further reduce the apoptosis of DHA-treated cells, and such an additive effect was obvious when apoptosis was induced at a low frequency. Longer-range stimulation of U937 cells with TNF showed that inhibition of apoptosis by preincubating cells with either DHA or vitamin E was not significant 9 h after TNF addition, but that preincubation with both DHA and vitamin E could reduce the proportion of apoptotic cells even at this time point. Our findings suggested that ingestion of nutrients such as DHA and vitamin E might exert beneficial effects on organ dysfunction associated with various TNF-related diseases.     

运动对胰岛素抵抗大鼠TNF-α和脂联素表达的影响

目的 探讨运动干预对高脂高糖饮食诱导的胰岛素抵抗大鼠循环及组织中肿瘤坏死因子（tumor necrosis factor-alpha,TNF-α）和脂联素表达的影响.方法 29只雄性S-D大鼠随机分为对照组9只和造模组20只,分别给予基础饲料与高脂高糖饲料喂养,6周后将造模成功的18只大鼠再随机分为模型组9只和运动组9只,运动干预6周后,测定血清TNF-α（放免法）和脂联素（酶联免疫吸附法）及肝脏和骨骼肌中TNF-α和脂联素mRNA表达（RT-PCR法）.结果 与对照组比较,模型组空腹血糖和胰岛素升高（5.06±0.38 vs 7.49±1.13,13.61±2.94 vs 33.57±4.87,P均〈0.05）,胰岛素敏感指数降低（-4.21±0.22 vs -5.51±0.16,P〈0.05）,血清TNF-α升高（2.39±0.44 vs 3.03±0.50,P〈0.05）,血清脂联素降低（0.86±0.08 vs 0.77±0.09,P〈0.05）;肝脏和骨骼肌中TNF-α mRNA均表达增强,脂联素mRNA表达明显减弱.与模型组比较,运动组空腹血糖及胰岛素明显降低（5.77±1.17 vs 7.49±1. 13,25.69±4.27 vs 33.57±4.87,P均〈0.05）,胰岛素敏感指数上升（-5.10±0.31 vs -5.51±0.16,P〈0.05）,血清TNF-α降低（2.40±0.59 vs 3.03±0.50,P〈0.05）,脂联素升高（0.86±0.10 vs 0.77±0.09,P〈0.05）;肝脏和骨骼肌中TNF-α mRNA均表达减弱,脂联素mRNA表达增强.结论 运动干预明显改善胰岛素抵抗,其机制可能与调节TNF-α和脂联素的表达有关.     

皖籍汉族人寻常型银屑病患者TNF-α基因多态性分析

目的　探讨TNF α基因多态性与皖籍汉族人寻常型银屑病的相关性。方法　采用PCR RFLP方法 ,检测皖籍汉族人 6 5例早发型 (Ⅰ型 )银屑病、2 2例迟发型 (Ⅱ型 )银屑病及 1 2 8例健康人TNFα- 2 38多态性。结果　早发型银屑病患者携带TNFα - 2 38.2 (TNF G/A基因型 )频率较对照组明显增高 (2 6 .2 %vs 1 0 .9% ) ,二者差异有显著性 (OR =2 .88,Pc<0 .0 5 ) ;而迟发型银屑病患者携带该基因型频率则与对照组差异无显著性 (9.1 %vs 1 0 .9% ,OR =0 .81 ,Pc>0 .0 5 )。但早发型银屑病男女患者携带TNFα- 2 38.2频率与相应对照组差异均无显著性 (Pc>0 .0 5 )。结论　TNFα- 2 38.2频率与皖籍汉族人寻常型银屑病发病类型明显关联 ,提示TNF α基因多态性可能为汉族人银屑病易感因子之一。     

Induction of apoptosis by a hexane extract of aged black garlic in the human leukemic U937 cells

BACKGROUND/OBJECTIVES

In this study, the apoptogenic activity and mechanisms of cell death induced by hexane extract of aged black garlic (HEABG) were investigated in human leukemic U937 cells.

MATERIALS/METHODS

Cytotoxicity was evaluated by MTT (3-(4, 5-dimethyl-thiazol-2-yl)-2, 5-diphenyl tetrazoliumbromide) assay. Apoptosis was detected using 4,6-diamidino-2-phenyllindile (DAPI) staining, agarose gel electrophoresis and flow cytometry. The protein levels were determined by Western blot analysis. Caspase activity was measured using a colorimetric assay.

RESULTS

Exposure to HEABG was found to result in a concentration- and time-dependent growth inhibition by induction of apoptosis, which was associated with an up-regulation of death receptor 4 and Fas legend, and an increase in the ratio of Bax/Bcl-2 protein expression. Apoptosis-inducing concentrations of HEABG induced the activation of caspase-9, an initiator caspase of the mitochodrial mediated intrinsic pathway, and caspase-3, accompanied by proteolytic degradation of poly(ADP-ribose)-polymerase. HEABG also induced apoptosis via a death receptor mediated extrinsic pathway by caspase-8 activation, resulting in the truncation of Bid, and suggesting the existence of cross-talk between the extrinsic and intrinsic pathways. However, pre-treatment of U937 cells with the caspase-3 inhibitor, z-DEVD-fmk, significantly blocked the HEABG-induced apoptosis of these cells, and increased the survival rate of HEABG-treated cells, confirming that HEABG-induced apoptosis is mediated through activation of caspase cascade.

CONCLUSIONS

Based on the overall results, we suggest that HEABG reduces leukemic cell growth by inducing caspase-dependent apoptosis through both intrinsic and extrinsic pathways, implying its potential therapeutic value in the treatment of leukemia.     

肿瘤坏死因子-a与血管生成的研究进展

肿瘤坏死因子-a(tumor necrosis factor-a,TNF-α)通过不同的途径促进血管的生成,对缺血脑组织的血管再生及肿瘤血管的生成发挥着关键的作用,TNF-α和机体的炎症反应、免疫反应都有着密切关系,在维持机体稳定性方面也起到很重要的作用。但TNF-α在血管新生的研究中呈现出复杂性和多重性,其在肿瘤以及脑缺血中的作用机制还不是很清楚,有待进一步研究。文章就TNF-α的结构、受体信号通路及其在血管生成中的作用进行综述。     

Ethanol increases tumor necrosis factor-alpha receptor-1 (TNF-R1) levels in hepatic, intestinal, and cardiac cells.

Chronic ethanol consumption leads to cell injury in virtually every tissue. Tumor necrosis factor-alpha (TNF-alpha) constitutes a major factor in the development of alcohol-induced liver injury. In alcohol-dependent subjects, elevated levels of plasma TNF-alpha are strongly predictive of mortality. Binding of TNF-alpha to TNF-alpha receptor-1 (TNF-R1) activates death domain pathways, leading to necrosis and apoptosis in most tissues, and it also increases the expression of intercellular adhesion molecules (i.e., ICAM-1), which promote inflammation. We determined whether ethanol exposure leads to increases in cellular TNF-R1. We incubated HepG2 human hepatoma cells and H4-II-E-C3 rat hepatoma cells with 25, 50, and 100 mM ethanol for various intervals of time up to 48 h. Human colonic adenocarcinoma cells (Caco-2 cells) and neonatal rat primary cardiomyocytes were also incubated with different concentrations of ethanol. Levels of TNF-R1 were measured either by a sandwich enzyme-linked immunosorbent assay (ELISA) method or by determining the extracellular transmembrane domain of TNF-R1 by an intact-cell ELISA method. Ethanol exposure for 48 h increased TNF-R1 levels in human hepatoma cells in a dose-dependent manner. Levels increased significantly by 164% at 50 mM and by 240% at 100 mM ethanol. Effects were time dependent and did not reach a plateau at 48 h. Similar increases in TNF-R1 were also observed in rat hepatoma cells (90% at 50 mM and 230% at 100 mM ethanol). Under similar conditions, Caco-2 cells showed a significant 80% increase in TNF-R1 levels at 200 mM ethanol, a concentration found in intestine. Neonatal rat primary cardiomyocytes showed TNF-R1 increases of 36% at 50 mM and 44% at 100 mM ethanol. These results indicate that exposure of different cell types to pharmacologic concentrations of ethanol increases TNF-R1 levels and may augment TNF-alpha-mediated cell injury in different tissues.     

转铁蛋白和肿瘤坏死因子-α的联合检测在肺结核化疗中的应用研究

目的 通过转铁蛋白(TRF)和肿瘤坏死因子-α(TNF-α)的联合检测,指导铁剂辅助的抗结核化疗,并对其应用价值进行研究.方法 肺结核患者随机均分为A和B两组,A组进行正规抗结核化疗,B组进行铁剂辅助的抗结核化疗,监测其疗效和TRF和TNF-α水平的变化.结果 在治疗各时间段,B组病灶显著吸收率、空洞闭合率显著高于A组(P＜0.05),痰菌涂片转阴率略高于A组(P＞0.05),TRF水平显著低于A组(P＜0.05),TNF-α水平略低于A组(P＞0.05).结论 TRF和TNF-α的联合检测可以帮助了解机体的铁代谢和抗结核免疫状况,铁剂辅助的抗结核化疗可帮助改善肺结核患者细胞免疫功能,提高临床治疗效果.     

TNF-α-1031位点基因多态性与冠心病的相关性研究

目的探讨肿瘤坏死因子-α-1031位点基因多态性与冠心病的关系。方法应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)技术检测121例冠心病患者和115例正常人的TNF-α基因型。结果TNF-α- 1031位点基因型TT、TC CC频率在患者组和对照组分别为66.9%、33.1%和64.3%、35.7%;等位基因T、C频率在患者组和对照组分别为82.6%、17.4%和80.9%、19.1%。两组基因型和等位基因频率比较差异没有显著性(P>0.05)。结论TNF-α-1031位点基因多态性与冠心病之间不存在明显相关性。