Hyaluronan production in human rheumatoid fibroblastic synovial lining cells is increased by interleukin 1β but inhibited by transforming growth factor β1

OBJECTIVES—To investigate the regulatory roles of interleukin 1β (IL1β), tumour necrosis factor α (TNFα), interferon γ (IFNγ) or transforming growth factor β1 (TGFβ1) on hyaluronan (HA) synthesis by human fibroblastic synovial lining cells.
METHODS—Concentrations of HA in culture supernatants of fibroblastic synovial lining cell line (RAMAK-1 cell line) with or without stimulation by IL1β, TNFα, IFNγ or TGFβ1 were measured by sandwich binding protein assay. Levels of HA synthase mRNA of the cells with or without stimulation were detected by reverse transcribed polymerase chain reaction. Molecular weights of HA in the culture supernatants of the cells with or without stimulation were measured using high performance gel permeation liquid chromatography.
RESULTS—HA synthesis by the cells was not significantly augmented by TNFα or by IFNγ. It was significantly stimulated by IL1β but inhibited by TGFβ1. Molecular weights of HA in the culture supernatants of the cells were unchanged by stimulation with TNFα. They were remarkably increased by stimulation with IL1β and IFNγ, but reduced with TGFβ1.
CONCLUSION—IL1β is an up regulator of HA synthesis, while TGFβ1 is a down regulator. HA production in the synovial lining cells of inflamed joints (for example, rheumatoid arthritis) might be regulated by the balance of these cytokines.

Keywords: synovial lining cells; hyaluronan, interleukin 1β; transforming growth factor β1     

Attenuation of dextran sodium sulphate induced colitis in matrix metalloproteinase-9 deficient mice

INTRODUCTIONMatrix metalloproteinases(MMPs)comprise a group of zinc and calcium-dependent endopeptidases that exhibit differential proteolytic activity against extracellular matrix(ECM)proteins.Based on substrate specificity,MMPs have been classically div…     

Effects of the anti-ICAM-1 monoclonal antibody on dextran sodium sulphate-induced colitis in rats

Increased expression of intercellular adhesion molecule-1 (ICAM-1) in the colon of inflammatory bowel disease (IBD) has been reported. We evaluated the effects of monoclonal antibodies to ICAM-1 on acute colitis induced by dextran sodium sulphate (DSS) in rats. Colitis was induced by feeding rats 3% DSS for 7 days. Anti-ICAM-1 antibody or vehicle alone was injected intraperitoneally in rats daily from day 0 to day 6. On day 7 the rats were killed and colitis was evaluated histologically. Prophylactic treatment with anti-ICAM-1 significantly attenuated colonic damage, neutrophil infiltration and the shortening of the colon in DSS colitis. Our findings demonstrate that ICAM-1 plays an important role in this model of inflammatory bowel disease. Although this study does not directly address the effect of anti-ICAM-1 therapy in IBD, our findings encourage experiments using therapies that target ICAM-1 in rats with already developed disease.     

Prophylactic effect of dietary glutamine supplementation on interleukin 8 and tumour necrosis factor α production in trinitrobenzene sulphonic acid induced colitis

Background—It is well established that glutaminesupplemented elemental diets result in less severe intestinal damage inexperimental colitis. However, few studies have examined the mode ofaction of glutamine in reducing intestinal damage.
Aims—To examine the effects of glutaminesupplemented elemental diets on the potent inflammatory cytokinesinterleukin 8 (IL-8) and tumour necrosis factor α (TNF-α) intrinitrobenzene sulphonic acid (TNBS) induced colitis which presentswith both acute and chronic features of ulcerative colitis.
Methods—Sprague-Dawley rats were randomised intothree dietary groups and fed 20% casein (controls), or 20% caseinsupplemented with either 2% glutamine (2% Gln) or 4% glutamine (4%Gln). After two weeks they received intracolonic TNBS to inducecolitis.
Results—Both Gln groups of rats gained more weight thanthe control group (p<0.05) which had progressive weight loss. Colon weight, macroscopic, and microscopic damage scores for the Gln groupswere lower than in the control group (p<0.05). IL-8 and TNF-αconcentrations in inflamed colonic tissues were lower in the Gln groupsthan in the control group (p<0.05), and correlated well with diseaseseverity. Bacterial translocation was lower both in incidence (p<0.05)and in the number of colony forming units (p<0.05) for the Gln groups,than in the control group. With respect to all indices studied, the 4%Gln group performed better than did the 2% Gln group.
Conclusion—Prophylactic glutamine supplementationmodulates the inflammatory activities of IL-8 and TNF-α in TNBSinduced colitis.

Keywords:glutamine; trinitrobenzene sulphonic acid; inflammatory bowel disease; rats; interleukin 8; tumour necrosis factorα

     

原发性胆汁性肝硬化患者肝组织转化生长因子β-1表达水平变化

目的 探讨原发性胆汁性肝硬化（PBC）患者肝组织转化生长因子-β1（TGF-β1）表达的变化。 方法 52例PBC患者接受超声引导下肝穿刺活检,选择病理科留取的正常肝组织20份作为对照,另选择20例健康人采集静脉血。采用免疫组化法检测肝组织TGFβ-1表达,采用ELISA法检测血清肿瘤坏死因子α（TNF-α）和白介素6（IL-6）水平。 结果 正常肝组织不表达或仅有少量TGF-β1表达,而PBC患者肝实质细胞胞浆内呈TGF-β1高表达;PBC患者血清TNF-α和IL-6水平分别为（28.71±13.54） pg/ml和（21.3±9.4） pg/ml,显著高于健康人【分别为（21.3±15.4） pg/ml和（2.1±1.6） pg/ml,P<0.01】;7例PBC肝组织肝纤维化S0期患者肝组织TGF-β1表达及血清TNF-α和IL-6水平分别为（0.5±0.2）10-2、（7.1±4.1） pg/ml和（5.1±1.0） pg/ml,显著低于12例S1期【（4.2±1.3） 10-2、（18.6±6.2） pg/ml、（11.5±3.6） pg/ml,P<0.01】、18例S2期【（6.9±1.2） 10-2、（27.3±9.9） pg/ml、（19.4±4.1） pg/ml,P<0.01】、9例S3期【（13.3±15.1） 10-2、（39.7±15.18） pg/ml、（27.3±8.1） pg/ml,P<0.01】和6例S4期【（21.2±17.1） 10-2、（53.4±17.3） pg/ml、（47.8±11.0） pg/ml,P<0.01】;15例Child-Pugh A级患者肝组织TGF-β1表达及血清TNF-α和IL-6水平分别为（1.9±1.6） 10-2、（12.2±3.1） pg/ml和（7.3±2.5） pg/ml,显著低于25例Child-Pugh B级【（15.9±13.6） 10-2、（32.9±8.6） pg/ml、（21.8±6.3） pg/ml,P<0.01】或12例C级患者【（22.6±18.5） 10-2、（49.1±19.3） pg/ml、（45.5±12.7） pg/ml,P<0.01】。 结论 PBC患者肝组织TGFβ-1表达及血清TNF-α和IL-6水平显著升高,可能与肝组织纤维化增生和/或肝功能受损有关。     

Role of T lymphocytes in rat 2,4,6-trinitrobenzene sulphonic acid (TNBS) induced colitis: increased mortality after gammadelta T cell depletion and no effect of alphabeta T cell depletion

BACKGROUND AND AIM: Indirect evidence suggests that CD4+ T cells have a pathogenic while gammadelta T cells have a protective role in the initiation and perpetuation of inflammatory bowel disease. To define the role of T cell subsets in a rat colitis model (2,4,6-trinitrobenzene sulphonic acid (TNBS)) we analysed colitis severity after effective depletion of T helper cells, alphabeta T cells, or gammadelta T cells. METHODS: T helper cells, alphabeta T cells, or gammadelta T cells were depleted using previously described monoclonal antibodies directed at the CD4 molecule (OX38), the CD2 molecule (OX34, both depleting CD4+ T cells), the alphabeta T cell receptor (R73), and the gammadelta T cell receptor (V65). Depletion was verified by flow cytometry and/or immunohistology. Colitis was induced using intracolonic application of TNBS. RESULTS: Surprisingly, depletion of T helper cells or alphabeta T cells had no influence on survival, macroscopic or microscopic scores, or myeloperoxidase activity following colitis induction. In contrast, depletion of gammadelta T cells resulted in significantly increased mortality (V65: 73%, n=15) compared with controls (30%, n=13; p<0.03). In addition, colitis was histologically more severe in the gammadelta T cell depleted group compared with controls (p<0.05). CONCLUSIONS: T helper cells or alphabeta T cells did not influence the initiation or perpetuation of rat TNBS colitis. In contrast, gammadelta T cells had a protective role in rat TNBS colitis as depletion caused increased mortality.     

肝泡状棘球蚴组织中HIF-1α、VEGFA的表达及对血管生成的作用

目的 探讨HIF-1α、VEGFA在沙鼠肝泡状棘球蚴组织的表达及血管生成过程中的作用。方法 126只沙鼠随机分成空白组(6只)、假手术组(60只)、模型组(60只),采用开腹直视肝脏穿刺法建立泡状棘球蚴动物模型,假手术组接种同体积的PBS,术后第3 d、7 d、14 d、28 d、42 d、56 d、70 d、84 d、98 d、112 d随机取6只沙鼠,取临近病变的边缘区组织及正常肝组织。采用HE观察病理改变;qRT-PCR、原位杂交、免疫组化检测HIF-1α、VEGFA表达,CD34标记微血管进行MVD计数。结果 HE染色根据病理特点将病程分为早期(14 d内)、中期(14 d~56 d)、晚期(56 d后)。模型组泡状棘球蚴组织随感染时间不同,其HIF-1αmRNA随感染时间呈动态改变,术后第14 d其表达量高于空白组、低于假手术组(F=82.732,P< 0.001);术后第42 d、112 d其相对表达量均高于空白组与假手术组(χ²=11.536,χ²=15.189,P< 0.01);模型组术后第14 d VEGFA mRNA相对表达量低于空白组及假手术组(χ²=15.174,P< 0.01);术后第42 d、112 d,VEGFA mRNA表达量均高于空白组与假手术组(χ²=15.158,χ²=15.158,P< 0.01)。模型组术后第14 d、42 d、112 d HIF-1α表达均高于空白组、假手术组(χ²=8.627,χ²=9.000,F=15.690,P< 0.01);模型组术后第14 d、42 d VEGFA表达高于空白组、假手术组(F=11.250, F=70.059,P< 0.001);模型组术后第14 d、42 d、112 d,其MVD-CD34均高于空白组、假手术组(χ²=12.517,P< 0.01,χ²=13.157,P< 0.01;χ²=13.220,P< 0.01)。结论 沙鼠感染肝泡状棘球蚴中期,病变边缘区HIF-1α、VEGFA表达均升高,同时伴有大量微血管生成,可能存在HIF-1α转录因子激活并上调VEGFA的表达,促进肝泡状棘球蚴组织边缘区的血管新生。;     

Expression of B7 costimulatory molecules by cells infiltrating the colon in experimental colitis induced by oral dextran sulfate sodium in the mouse

BACKGROUND AND AIM: T-cell activation, mediated by the interaction with major histocompatibility complex (MHC)-peptide complexes and B7 costimulatory molecules on antigen-presenting cells, is an essential event in the pathogenesis of inflammatory bowel disease (IBD). We investigated the expression of B7 costimulatory molecules on cells in the colon in an experimental mouse model of IBD to determine whether the B7/ligand interaction could provide a target for therapeutic intervention in IBD. METHODS: Experimental colitis was induced in mice by oral consumption of water substituted with 5% dextran sulfate sodium (DSS). Mice (n=4) were killed 1, 2, 3, 4 and 7 days after commencing DSS consumption, and colonic tissue was collected and examined immunohistochemically for T cells, B cells, macrophages and cells expressing B7-1 or B7-2. RESULTS: Compared to control mice drinking water, macrophage numbers in the colonic epithelium were elevated sevenfold by day 1 and T cells were elevated threefold by day 3 following commencement of DSS consumption. Numbers of infiltrating B7-positive (B7+) cells were not significantly elevated until day 7 when B7-1+, B7-2+ cells and macrophages were increased 20-fold compared to normal mice. CONCLUSION: These results demonstrate that an initial and rapid infiltration of the colonic epithelium by B7-negative macrophages is followed by an infiltration of T cells and subsequent upregulation of the B7 costimulatory molecules potentiating the inflammatory reaction in this disease model. These results suggest an intervention strategy based on the blockade of the B7-costimulatory axis could find application in the treatment of inflammatory bowel disease.     

Differential susceptibility of multidrug resistance protein-1 deficient mice to DSS and TNBS-induced colitis

The molecular mechanisms underlying inflammatory bowel diseases (IBD) are incompletely characterized. MRP-1, normally expressed in the large and small bowel epithelium, serves as a multidrug resistance protein. In this report we explored the role of MRP1 in IBD. Mrp1-deficient mice (mrp1 ^–/–) were subjected to two different models of IBD. The mrp1 ^–/– mice and wild-type (WT) mice showed equal induction of TNBS colitis, a hapten-induced T-cell mediated disease. However, in DSS colitis more severe disease was observed in mrp1 ^–/– mice. In a survival study, mortality of mrp1 ^–/– mice was higher. In nonlethal DSS colitis, the mean histological colitis score was significantly higher in mrp1 ^–/– mice and showed particularly severe epithelial damage. Although endogenous LTB₄ levels were significantly increased in mrp1 ^–/– mice, treatment with a LTB₄ antagonist did not reduce disease. We conclude that MRP-1 has an important role in the intestinal epithelial resistance to exogenous injury, but MRP-1 does not affect T-lymphocyte mediated mucosal damage.     

New mechanism of transforming growth factor‐β signaling in hepatoma: Dramatic up‐regulation of tumor initiating cells and epidermal growth factor receptor expression

Aim: Transforming growth factor‐β (TGF‐β) has dual activity in tumor cells. We studied the effect of TGF‐β on tumor‐initiating cells (TICs), which are similar in self‐renewal and differentiation features to normal adult stem cells. Methods: We used side population (SP) cells that exclude DNA binding dye Hoechst 33342 to obtain TICs, studied the differences in the kinetics of the SP cell response to TGF‐β treatment between hepatic tumor cell lines, and performed gene analysis. Results: SP cells from all cell lines have higher proliferative ability compared to non‐SP cells and they are drug resistant. TGF‐β treatment increased the percentage of SP cells (%SP) and the survival rate; chemotherapeutic drug resistance developed only in K‐251 SP cells. Gene analysis showed that TGF‐β up‐regulated epidermal growth factor receptor (EGFR) only in K‐251 cells. There were no EGFR mutations in K‐251, which had been reported in lung cancer. Knockdown of Smad4 using the small‐interfering RNA technique in K‐251 cells inhibited EGFR overexpression and significantly decreased the %SP. In contrast, the JNK inhibitor had little effect on EGFR expression or the %SP. Conclusion: TGF‐β treatment of K‐251 cells causes tumor progression and the anti‐cancer drug resistant phenotype by increasing SP.     

Effect of intestinal ischemia-reperfusion on expressions of endogenous basic fibroblast growth factor and transforming growth factor betain lung and its relation with lung repair

AIM:To study the changes of endogenous transforming growth factor beta(TGFbeta) and basic fibroblast growth factor (bFGF) in lung following intestinal ischemia and reperfusion injury and their effects on lung injury and repair.METHODS:Sixty Wistar rats were divided into five groups, which underwent sham-operation, ischemia (45 minutes), and reperfusion (6, 24 and 48 hours, respectively) after ischemia (45 minutes). Immunohistochemical method was used to observe the localization and amounts of both growth factors.RESULTS:Positive signals of both growth factors could be found in normal lung, mainly in alveolar cells and endothelial cells of vein. After ischemia and reperfusion insult, expressions of both growth factors were increased and their amounts at 6 hours were larger than those of normal control or of 24 and 48 hours after insult.CONCLUSION:The endogenous bFGF and TGF beta expression appears to be upregulated in the lung following intestinal ischemia and reperfusion, suggesting that both growth factors may be involved in the process of lung injury and repair.