Increased adhesion molecule expression in serosal fibroblasts isolated from patients with inflammatory bowel disease is secondary to inflammation

OBJECTIVE: To examine the expression of adhesion molecules by serosal and dermal fibroblasts in patients with inflammatory bowel disease. SUMMARY BACKGROUND DATA: The pathophysiologic process that leads to stricture formation in Crohn's disease (CD) is unknown. Serosal fibroblasts in these patients have an enhanced ability to contract collagen. This property may be reflected in fibroblast adhesion molecule expression, which in turn may be constitutive or secondary to the inflammatory process in patients with CD. METHODS: Fibroblasts were isolated from inflamed and macroscopically normal serosa of patients with CD or ulcerative colitis (UC) and from normal serosa of patients with colon cancer. Dermal fibroblasts were also isolated from the wound edge. Cell surface and whole cell expression of ICAM-1 were evaluated by flow cytometry and Western blot analysis, respectively. NFkappaB was measured by mobility shift assay in parallel experiments. Interleukin 1beta was added to the culture medium. RESULTS: Expression of ICAM-1 and NFkappaB, increased in patients with both CD and UC, was unaltered by interleukin 1beta. The whole cell concentration of ICAM-1 was greater in patients with CD than in patients with UC. Dermal fibroblasts did not display these features. CONCLUSIONS: Patients with inflammatory bowel disease display enhanced ICAM-1 expression in serosal fibroblasts but not dermal fibroblasts, indicating a secondary response to inflammation.     

Increased vascular endothelial growth factor production in fibroblasts isolated from strictures in patients with Crohn's disease

BACKGROUND: Vascular endothelial growth factor (VEGF) is a potent angiogenic factor that is implicated in early wound healing and fibrosis. Fibroblasts may initiate stricture formation in Crohn's disease through overexpression of VEGF. The aim of this study was to examine VEGF expression and regulation in fibroblasts isolated from patients with Crohn's disease. METHODS: Fibroblasts were isolated by a primary explant technique from serosal biopsies of non-strictured and strictured segments of bowel from eight patients undergoing resection for Crohn's disease, and normal colon from six patients undergoing resection for benign and malignant colorectal disease. Fibroblasts were cultured with transforming growth factor (TGF) beta and corticosteroids. After 24 h the culture supernatant was collected for VEGF assay by enzyme-linked immunosorbent assay. RESULTS: VEGF production was significantly higher in fibroblasts isolated from strictures (mean(s.e.m.) 1980(260) pg/ml) than from non-strictured segments (1116(165) pg/ml) in patients with Crohn's disease or control fibroblasts (898(93) pg/ml). TGF-beta increased VEGF production in normal and non-strictured Crohn's fibroblasts. Corticosteroids suppressed unstimulated VEGF production in all groups. CONCLUSION: Enhanced serosal fibroblast VEGF production might play a role in initiating stricture formation in Crohn's disease. VEGF production in serosal fibroblasts is sensitive to stimulation with TGF-beta. Corticosteroids may reduce stricturing through suppression of VEGF.     

Expression and regulation of connective tissue growth factor by transforming growth factor beta and tumour necrosis factor alpha in fibroblasts isolated from strictures in patients with Crohn's disease

BACKGROUND: Connective tissue growth factor (CTGF) stimulates fibroblast proliferation and extracellular matrix production. Fibroblasts may initiate stricture formation in Crohn's disease through overexpression of CTGF. Stricturing that occurs in patients with Crohn's disease after treatment with anti-tumour necrosis factor (TNF) alpha may be due to dysregulation of CTGF homeostasis. The aim of this study was to examine CTGF expression and regulation in fibroblasts isolated from patients with Crohn's disease. METHODS: Fibroblasts were isolated by a primary explant technique from serosal biopsies of strictured segments of bowel in eight patients undergoing resection for Crohn's disease and from normal colon in seven patients having resection for benign or malignant colorectal disease. Cells were stimulated with transforming growth factor (TGF) beta and TNF-alpha. CTGF protein and mRNA expression were measured by western blotting and real-time polymerase chain reaction respectively. RESULTS: Mean(s.d.) CTGF protein expression in strictured Crohn's fibroblasts was higher than that in normal fibroblasts (56.5(9.7) versus 17.0(10.0) respectively; P = 0.011). In normal and strictured Crohn's fibroblasts, culture with TGF-beta increased CTGF protein and mRNA expression. Co-culture of normal fibroblasts with TNF-alpha suppressed TGF-beta-stimulated CTGF expression. CONCLUSION:: Increased expression of CTGF in strictured Crohn's fibroblasts underlies its role in fibrosis. TNF-alpha suppresses fibrosis by downregulating fibroblast CTGF expression, an effect that may be lost following anti-TNF-alpha treatment, thereby promoting stricture formation.     

Vasoactive intestinal peptide inhibits adhesion molecule expression in activated human colon serosal fibroblasts by preventing NF-kappaB activation

BACKGROUND: Stricture formation in Crohn's disease (CD) occurs as a result of persistent intestinal inflammatory activation, which leads to enhanced adhesion molecule expression in serosal fibroblasts (SFs). Vasoactive intestinal peptide (VIP) has anti-inflammatory and immunoregulatory properties. Treatment with VIP prevents experimental CD in animal models at the clinical and pathologic levels. The present study reports the effect of VIP on the expression of intracellular adhesion molecule-1 (ICAM-1) in IL-1beta-stimulated human colon SFs. MATERIALS AND METHODS: Primary human colon SFs were incubated with or without IL-1beta (10 ng/mL) in the presence or absence of VIP at various concentrations (0.1 to 100 nM) for designated time. Cell surface and cytosolic ICAM-1 expression were evaluated by flow cytometry and Western blot analysis, respectively. The DNA binding capacity of NF-kappaB was analyzed by electrophoretic mobility shift assay. The phosphorylation of IkappaB-alpha was examined by Western blot analysis. RESULTS: VIP inhibited IL-1beta-induced expression of ICAM-1 in a dose-dependent manner. The IL-1beta-induced ICAM-1 was also inhibited by a potent inhibitor of NF-kappaB, MG132. VIP also decreased IL-1beta-induced NF-kappaB DNA binding capacity and phosphorylation of IkappaB-alpha. CONCLUSION: VIP has an inhibitory effect on IL-1beta-induced ICAM-1 expression in SFs, which may be associated with NF-kappaB activity. This may make VIP potentially a novel therapeutic agent for preventing stricture formation in Crohn's disease.     

Contribution of interleukin 17 to human cartilage degradation and synovial inflammation in osteoarthritis

OBJECTIVE: To compare the effect of interleukin (IL)-17, IL-1beta and TNF-alpha on chemokine production by human chondrocytes and synovial fibroblasts isolated from patients with osteoarthritis (OA). The expression of IL-1beta mRNA by OA chondrocytes was also assessed, as well as the presence and expression of IL-17 receptor (IL-17R) in OA chondrocytes and synovial fibroblasts after stimulation with IL-17, IL-1beta and TNF-alpha. DESIGN: Synovial fibroblasts and chondrocytes isolated from patients with OA were stimulated in vitro with IL-17, IL-1beta or TNF-alpha. Supernatants were collected and immunoassayed for the presence of IL-8, GRO-alpha (CXC chemokines) and MCP-1, RANTES (CC chemokines). The cells were used to detect the presence of IL-17R and the expression of IL-17R mRNA. Stimulated chondrocytes were also used to detect IL-1beta production and mRNA expression. RESULTS: IL-17 upregulated the release of IL-8 and GRO-alpha both by synovial fibroblasts and chondrocytes, and the release of MCP-1 only by chondrocytes. IL-17 was a weaker stimulator than IL-1beta and TNF-alpha, except for GRO-alpha release which was maximally upregulated by IL-1beta, less by IL-17 and minimally by TNF-alpha. When compared to IL-1beta, IL-17 was more active on chondrocytes than on fibroblasts. In chondrocytes the expression of IL-1beta mRNA was enhanced by IL-17 and TNF-alpha, with a maximum level reached by IL-1beta. IL-17 and TNF-alpha stimulated IL-1beta release in few subjects. Neither IL-17, IL-1beta nor TNF-alpha modulated the presence of IL-17R and the expression of IL-17R mRNA. CONCLUSIONS: These data suggest that IL-17 could contribute to cartilage breakdown and synovial infiltration in OA by inducing both the release of chemokines by chondrocytes and synovial fibroblasts and, in a less extent, the synthesis of IL-1beta by chondrocytes.     

TNF-alpha and IL-1beta-mediated regulation of MMP-9 and TIMP-1 in renal proximal tubular cells

BACKGROUND: Tubulointerstitial fibrosis is a morphologic hallmark of chronic kidney disease and is a key factor in the prediction of progression to end-stage renal failure. Disruption of tubular basement membrane and interstitial extracellular matrix (ECM) via cytokine-induced alterations in matrix metalloproteinases (MMPs), and tissue inhibitors of metalloproteinases (TIMPs) may be an important mechanism in this process. The presence of the proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) and their effects on proximal tubular cells may be critical in this process. METHODS: Human proximal tubular cells were cultured in hormonally defined medium. Cells at 80% confluency were exposed to TNF-alpha (0.1 to 100 ng/mL) or IL-1beta (0.1 to 100 ng/mL) or a combination of both for 48 hours. Activity and expression of MMP-9 was examined by gelatin zymography and Western blot analysis. TIMP-1 expression was analyzed by Western blotting. Signaling through cytokine receptors, protein kinase C (PKC) and mitogen-activated protein kinase (MAPK) pathways was investigated. RESULTS: TNF-alpha but not IL-1beta resulted in a dose-dependent increase in the latent form of MMP-9. TIMP-1 was decreased by treatment with either TNF-alpha or IL-1beta. Cotreatment with IL-1beta abolished the induction of MMP-9 but augmented the inhibition of TIMP-1 in the presence of TNF-alpha. Inhibition of PKC provided evidence of the importance of this pathway in mediating the cytokine-induced suppression of TIMP-1 in human kidney (HK-2) cells. Activation of the extracellular signal-regulated protein kinase (ERK1/2) MAPK mediated the up-regulation of MMP-9 by TNF-alpha whereas p38 was found to be involved in the IL-1beta-mediated inhibition of TNF-alpha-stimulated MMP-9. CONCLUSION: The differential effects of TNF-alpha and IL-1beta on proximal tubular MMP-9 and TIMP-1 expression are mediated through the TNF-RI, the IL-1-RI and the different signaling pathways of PKC, ERK1/2, and p38 MAPK. These findings may provide new insights into the role of proinflammatory cytokines TNF-alpha and IL-1beta in the development and possible therapeutic intervention in tubulointerstitial fibrosis.     

Transforming growth factor-beta promotes pro-fibrotic behavior by serosal fibroblasts via PKC and ERK1/2 mitogen activated protein kinase cell signaling

OBJECTIVE: To assess the role of fibroblasts, transforming growth factor (TGF)-beta, and cell signal pathways in promoting fibrosis in Crohn's disease (CD). SUMMARY BACKGROUND DATA: Intestinal strictures are a major source of morbidity in CD. Fibroblasts found at sites of stricture promote fibrogenesis. The mechanisms underlying this pro-fibrotic behavior remain elusive. METHODS: Fibroblasts were isolated from strictured and macroscopically normal serosa in patients with CD and from normal serosa in patients with colorectal cancer. Whole cell connective tissue growth factor (CTGF) and fibronectin expression were determined by Western blot analysis. Fibroblast type I collagen expression was evaluated by real-time PCR, while fibroblast contractile activity was measured using fibroblast populated collagen lattices. Cells were stimulated with TGF-beta1 and inhibitors of the protein kinase C (PKC) and ERK 1/2 mitogen activated protein (MAP) kinase cell signaling pathways. RESULTS: Stricture fibroblasts displayed enhanced constitutive expression of fibronectin. TGF-beta promoted fibroblast CTGF, fibronectin, and type I collagen expression and enhanced fibroblast contractile activity. Inhibition of PKC reduced basal collagen expression and contractile activity in Crohn's fibroblasts and attenuated the effect of TGF-beta on fibroblast CTGF, fibronectin, and collagen I expression as well as fibroblast contractility. ERK 1/2 inhibition had a similar effect on TGF-beta-induced CTGF and fibronectin expression. CONCLUSIONS: TGF-beta is a critical pro-fibrotic growth factor in CD, and its effects are mediated via PKC and ERK 1/2 MAP kinase cell signaling. These pathways may represent novel therapeutic targets for patients with CD characterized by recurrent intestinal stricture formation.     

Interleukin-17, a regulator of angiogenic factor release by synovial fibroblasts

OBJECTIVE: Angiogenesis is a process stimulated in inflamed synovium of patients with osteoarthritis (OA), and contributes to the progression of the disease. Synovial fibroblasts secrete angiogenic factors, such as vascular endothelial growth factor (VEGF), an up-regulator of angiogenesis, and this ability is increased by interleukin (IL)-1beta. The purpose of this study was to verify whether IL-17 contributes and/or synergizes with IL-1beta and tumor necrosis factor (TNF)-alpha in vessel development in articular tissues by stimulating the secretion of proangiogenic factors by synovial fibroblasts. DESIGN: We stimulated in vitro synovial fibroblasts isolated from OA, rheumatoid arthritis (RA) and fractured patients (FP) with IL-17 and IL-1beta and from OA patients with IL-17, IL-1beta and TNF-alpha. In the supernatants from the cultures, we assayed the amount of VEGF by immunoassay and other angiogenic factors (keratinocyte growth factor, KGF; hepatocyte growth factor, HGF; heparin-binding endothelial growth factor, HB-EGF; angiopoietin-2, Ang-2; platelet-derived growth factor B, PDGF-BB; thrombopoietin, TPO) by chemiluminescence; semiquantitative RT-PCR was used to state mRNA expression of nonreleased angiogenic factors (Ang-2 and PDGF-BB) and tissue inhibitors of metalloproteinase (TIMP)-1. RESULTS: IL-17, TNF-alpha and IL-1beta increased VEGF secretion by synovial fibroblasts from OA patients. IL-17 and IL-1beta also increased VEGF secretion in RA and FP. Besides, IL-17 increased KGF and HGF secretions in OA, RA and FP; in OA and RA, IL-17 also increased the HB-EGF secretion and the expression of TIMP-1 as protein and mRNA. In OA patients IL-17 had an additive effect on TNF-alpha-stimulated VEGF secretion. CONCLUSIONS: These results suggest that IL-17 is an in vitro stimulator of angiogenic factor release, both by its own action and by cooperating with TNF-alpha.     

Cytokine regulation of ICAM-1 expression on human renal tubular epithelial cells in vitro.

Regulation of the intercellular adhesion molecule-1 (ICAM-1) expression on human renal tubular epithelial cells in culture (hKEC-1) was investigated. A large proportion of hKEC-1 cells from the primary cultures expressed the ICAM-1 antigen. Supernatants from mixed lymphocyte reaction (MLR) of both specific and third-party combinations augmented the expression of the ICAM-1 antigen, in a dose-dependent manner. A kinetic study revealed maximal augmentation by MLR supernatant on the first day, with a gradual decrease thereafter. Among several recombinant human cytokines tested, i.e., interferon-gamma, tumor necrosis factor-alpha, interleukin 1 alpha and beta, and IL-4, IFN-gamma, TNF-alpha, and IL-1 alpha/beta were shown to augment the expression of ICAM-1. MLR supernatants and IFN-gamma were more effective in augmenting ICAM expression than TNF-alpha and IL-1 alpha/beta. IFN-gamma upregulated ICAM-1 expression in a dose-dependent manner, and maximal augmentation was achieved on the first day. The MLR supernatants were shown to contain IFN-gamma and TNF-alpha, and the activity of the MLR supernatant was partially inhibited by neutralizing antibody against IFN-gamma. These data suggest that cytokines, especially IFN-gamma, TNF-alpha, and IL-1 alpha/beta, released by T cells and antigen-presenting cells upon recognition of alloantigens upregulate ICAM-1 expression on renal tubular epithelial cells. This may result in an increase in the attachment of graft-infiltrating T cells to the renal tubular cells, by the ICAM-1-LFA-1 interaction.     

Role of p38 mitogen-activated protein kinase in Kupffer cell secretion of the proinflammatory cytokines after burn trauma

This study was designed to investigate the role of p38 mitogen-activated protein (MAP) kinase on Kupffer cells (KCs) secretion of proinflammatory cytokines such as tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta and hepatic injury following burn trauma. Sprague-Dawley rats were randomized into four groups: (1) sham burn rats given vehicle, (2) sham burn rats given the p38 MAP kinase inhibitor SB203580 (10mg/kg i.v., 15min and 12h after sham burn), (3) rats given a 30% total body surface area (TBSA) full-thickness burn and fluid resuscitation plus vehicle, and (4) burn rats given injury and fluid resuscitation plus SB203580. Rats from each group were killed at 24h post-burn to examine plasma aspartate transaminase (AST) and alanine transaminase (ALT) and KCs were isolated. The KCs secretion of TNF-alpha and IL-1beta and p38 MAP kinase activity (by Western blot analysis) were also examined. These studies showed by more significant activation of p38 MAP kinase in KCs harvested from burn rats than from shams. Burn trauma resulted in hepatic dysfunction and promoted KCs secretion of TNF-alpha and IL-1beta. SB203580 inhibited p38 MAP kinase activity, reduced KCs secretion of proinflammatory cytokines, and alleviated burn-mediated hepatic dysfunction. These data suggest p38 MAP kinase activation is one important aspect of the signaling event that may mediate the KCs secretion of proinflammatory cytokines TNF-alpha and IL-1beta following burn trauma.     

p38丝裂原活化蛋白激酶信号转导通路在严重烧伤大鼠枯否细胞肿瘤坏死因子α和白细胞介素1β产生中的作用

目的 探讨p38丝裂原活化蛋白激酶(MAPK)信号转导通路在严重烧伤大鼠枯否细胞(KCs)促炎性细胞因子肿瘤坏死因子α(TNF-α)和白细胞介素1β(IL-1β)产生中的作用。方法 健康成年的雄性SD大鼠32只,随机分为：假烫组;假烫 SB203580组;烧伤对照组;烧伤 SB203580组,每组8只。假烫或烧伤24h后分离出肝脏KCs,培养18h后加入50ng／ml的LPS进行刺激,18h后取上清液,用酶联免疫吸附法(ELISA)测定TNF-α和IL-1β的含量,并收集KCs,实时逆转录聚合酶链反应检测KCs内TNF-α和IL-1β mRNA表达的改变,蛋白印迹(Western blot)法检测KCs中p38MAPK和JNK活性的变化。结果 烧伤大鼠分离出的KCs培养上清液中TNF-α和IL-1β含量、KCs中TNF-α和IL-1β mRNA的表达均较假烫组的明显增强,同时KCs中p38 MAPK活性和JNK活性升高,SB203580能显著抑制大鼠KCs上清液中TNF-α和IL-1β含量、KCs中TNF-α和IL-1β mRNA的表达和p38MAPK活性的升高,对JNK活性无影响。结论p38MAPK信号转导通路介导了严重烧伤大鼠KCs促炎性细胞因子TNF-α和IL-1β的产生。     

Effect of Crohn's disease on bone metabolism in vitro: a role for interleukin-6.

Circulating proinflammatory cytokines may be involved in osteopenia associated with Crohn's disease (CD). Therefore, the effect of interleukin (IL)-6, IL-1beta, and tumor necrosis factor (TNF) a contained in Crohn's serum on bone formation was examined in a bone organ culture system. Initially, serum levels of IL-6, IL-1beta, and TNF-a were determined by ELISA in newly diagnosed, untreated children with CD and healthy age-matched controls. Serum IL-6 levels were significantly higher in patients with CD than in controls (23.9 +/- 2.8 pg/ml vs. 0.7 pg/ml +/- 0.2; p < 0.001), whereas IL-1beta and TNF-alpha serum levels were not. In the organ culture studies, 20-day-old fetal rat parietal bones were incubated for 96 h with CD or control serum, serum preincubated with a neutralizing antibody to each cytokine or a nonimmune immunoglobulin control, and with IL-6. Bone formation measured by assaying calcium content and dry weight was significantly decreased in bones exposed to Crohn's serum. Light microscopy of the bones treated with CD serum revealed a discontinuous, uneven mineralized bone matrix and disorganized osteoblasts with altered morphology. Incubation with an antibody that neutralized IL-6 activity prevented the change in osteoblast and bone morphology. TNF-a and IL-1beta antibodies had no apparent effects. Collagen synthesis and DNA content were not affected by CD serum. Also, addition of IL-6 to the culture medium decreased mineralization. These results suggest that IL-6 is a mediator of the effects of Crohn's serum on in vitro mineralization and may be a contributing factor to the osteopenia associated with CD.     

p38丝裂原活化蛋白激酶在烧伤大鼠急性肺损伤中的作用机制

目的　研究 p38丝裂原活化蛋白激酶 (MAPK)信号转导通路在严重烧伤大鼠肺部促炎细胞因子肿瘤坏死因子α(TNF α)、白细胞介素 1β(IL 1β)产生及肺血管内皮细胞损伤中的作用和相关机制。　方法　健康成年雄性SD大鼠 4 8只 ,随机分为假烫 (A)组、烫伤对照 (B)组和烫伤 p38MAPK抑制剂SB2 0 35 80(C)组 ,每组各 16只。观察烫伤 (以下称烧伤 ) 2 4h后大鼠血清和支气管肺泡灌洗液 (BALF)中TNF α和IL 1β含量、血浆和肺脏微血管vonWillebrand因子 (vWF)含量、肺脏激活蛋白 1(AP 1)活性等指标的改变。　 结果　B组大鼠烧伤后 2 4h血清和BALF中TNF α和IL 1β含量明显增高 ,血浆vWF含量为 (194 .2± 2 8.3) % ,显著高于A组的 (93.2± 14 .3) % (P <0.0 1);肺脏微血管vWF含量的积分值为 1.1± 0 .3,显著低于A组的 3.3± 0 .4 (P <0.0 1);其肺脏AP 1活性上升。C组血清和BALF中TNF α和IL 1β含量、血浆及肺脏微血管vWF含量、肺脏AP 1的活性较B组变化幅度明显偏小。　结论　p38MAPK活化后 ,通过活化转录因子AP 1,介导了严重烧伤后肺脏促炎性细胞因子TNF α和IL 1β的产生和肺血管内皮细胞的损伤     

Variations in IB1/JIP1 expression regulate susceptibility of beta-cells to cytokine-induced apoptosis irrespective of C-Jun NH2-terminal kinase signaling

We previously reported that interleukin-1beta (IL-1beta) alone does not cause apoptosis of beta-cells, whereas when combined with gamma-interferon (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha), it exerts a distinct apoptotic effect. Studies in beta-cell lines indicated that IL-1beta reduced expression of islet brain (IB)-1/JNK interacting protein (JIP)-1, a JNK scaffold protein with antiapoptotic action. We examined whether variations in IB1/JIP-1 expression in purified primary beta-cells affect their susceptibility to cytokine-induced apoptosis. Exposure to IL-1beta for 24 h decreased cellular IB1/JIP-1 content by 66 +/- 17%; this IL-1beta effect was maintained in the presence of TNF-alpha + IFN-gamma, which did not influence IB1/JIP-1 levels by themselves. Addition of IL-1beta to TNF-alpha + IFN-gamma increased apoptosis from 20 +/- 2% to 59 +/- 5%. A similar increase in TNF-alpha + IFN-gamma-induced apoptosis was produced by adenoviral expression of antisense IB1/JIP-1 and was not further enhanced by addition of IL-1beta, indicating that IL-1beta-mediated suppression of IB1/JIP-1 in beta-cells increases their susceptibility to cytokine-induced apoptosis. However, adenovirally mediated overexpression of IB1/JIP-1 also potentiated TNF-alpha + IFN-gamma-induced apoptosis, suggesting that the antiapoptotic effect of IB1/JIP-1 depends on well-defined cellular levels. We conclude that the IB1/JIP-1 level in beta-cells can control their susceptibility to apoptosis independent of JNK signaling.     

p38丝裂原活化蛋白激酶在应激性溃疡发病中的作用

目的探讨p38丝裂原活化蛋白激酶(MAPK)在应激性溃疡发生中的作用。方法80只SD大鼠分成正常对照组(10只)、浸水-束缚(WIR)应激模型组(0.5、1、2、4和6h时间点各10只)和p38特异性抑制剂CNI1493处理组(低剂量和高剂量组各10只)。CNI1493处理组于应激前2h尾静脉注射1或10mg/kg的CNI1493。胃黏膜病变程度采用溃疡指数计分评价,磷酸化和总p38MAPK表达采用蛋白印迹法(Westernblot)检测,肿瘤坏死因子α(TNFα)和白细胞介素1β(IL1β)基因表达采用Northernblot方法检测。结果WIR应激后大鼠胃黏膜p38MAPK发生持续活化,其最大活化发生于应激后1h,为正常水平的(6.8±3.2)倍(P<0.01)。使用CNI1493阻断p38MAPK活化后,胃黏膜损伤程度显著减轻,同时促炎性细胞因子TNFα和IL1β基因表达也明显下调。结论p38MAPK活化在实验性应激性溃疡的发生中发挥了重要作用。     

Markers of inflammation and atherosclerosis in Egyptian patients with systemic lupus erythematosus

BACKGROUND: Cardiovascular events are markedly increased in systemic lupus erythematosus (SLE) and the mechanism of atherogenesis remains poorly understood. Low-grade inflammation and endothelial dysfunction play pivotal roles in the initiation, progression and propagation of the atherosclerotic process. Several methods have been employed to assess endothelial function, among them the measurement of biomarkers of endothelial activation and dysfunction (intercellular adhesion molecule (ICAM)-1). Since then, it has been reported that such biomarkers play a more important role than traditional risk factors in cardiovascular disease. OBJECTIVE: To measure (tumour necrosis factor (TNF)-alpha, interleukin (IL)-6 and ICAM-1) levels as markers of inflammation and atherosclerosis in 40 Egyptian patients with SLE with various degrees of activity in comparison with 20 healthy volunteers, and to investigate their relationship to disease activity and hypertension. METHODS: Sixty subject (40 with SLE and 20 healthy controls) were the subject of this study, their clinical disease activity was scored according to the SLE Disease Activity Index (SLEDAI), and serum sampling was obtained for TNF-alpha, IL-6 and ICAM-1 level assay. Renal biopsy was carried out and examined by light microscopy. The mean level of TNF-alpha, IL-6 and ICAM-1 were significantly higher in SLE patients with active disease (766.95 +/- 357.82 Pg/mL, 135.4 +/- 54.23 Pg/mL, 826.05 +/- 367.1 Pg/mL) when compared with those with inactive disease (314.01 +/- 100.87 Pg/mL, 47.33 +/- 18.61 pg/mL, 441.33 +/- 225.19 Pg/mL) and healthy control volunteers (172.7 +/- 39.19 Pg/mL, 21.15 +/- 10.99 Pg/mL, 111.5 +/- 17.36 Pg/mL), respectively. Furthermore, these levels were significantly higher in hypertensive (614.08 +/- 333.05 Pg/mL, 107.86 +/- 54.96 Pg/mL and 862.13 +/- 333.29 Pg/mL) compared to normotensive patients (267.5 +/- 112.72 Pg/mL, P = 0.008, 35.75 +/- 20.26 Pg/mL, P = 0.02I, and 337.25 +/- 235.62 Pg/mL, P = 0.02) for TNF-alpha, IL-6 and ICAM, respectively. There were no statistically significant difference regarding age, sex, smoking, cholesterol and high-density lipoprotein (HDL) levels between hypertensive and normotensive patients. CONCLUSION: A high concentration of soluble ICAM-1 in Egyptian patients with SLE and nephritis is reported here for the first time. Our finding of increased concentrations of TNF-alpha, IL-6 and ICAM-1 in Egyptian patients with SLE and lupus nephritis underlines the importance of inflammation and endothelial involvement in this disorder, but their predictive value in the disease monitoring needs to be further studied.     

The effect of aprotinin on hypoxia-reoxygenation-induced changes in neutrophil and endothelial function

BACKGROUND AND OBJECTIVE: An acute inflammatory response associated with cerebral ischaemia-reperfusion contributes to the development of brain injury. Aprotinin has potential, though unexplained, neuroprotective effects in patients undergoing cardiac surgery. METHODS: Human neutrophil CD11 b/CD18, endothelial cell intercellular adhesion molecule-1 (ICAM-1) expression and endothelial interleukin (IL)-1beta supernatant concentrations in response to in vitro hypoxia-reoxygenation was studied in the presence or absence of aprotinin (1600 KIU mL(-1)). Adhesion molecule expression was quantified using flow cytometry and IL-1beta concentrations by enzyme-linked immunosorbent assay. Data were analysed using ANOVA and post hoc Student-Newman-Keuls test as appropriate. RESULTS: Exposure to 60-min hypoxia increased neutrophil CD11b expression compared to normoxia (170+/-46% vs. 91+/-27%, P = 0.001) (percent intensity of fluorescence compared to time 0) (n = 8). Hypoxia (60 min) produced greater upregulation of CD11b expression in controls compared to aprotinin-treated neutrophils [(170+/-46% vs. 129+/-40%) (P = 0.04)] (n = 8). Hypoxia-reoxygenation increased endothelial cell ICAM-1 expression (155+/-3.7 vs. 43+/-21 mean channel fluorescence, P = 0.0003) and IL-1beta supernatant concentrations compared to normoxia (3.4+/-0.4 vs. 2.6+/-0.2, P = 0.02) (n = 3). Hypoxia-reoxygenation produced greater upregulation of ICAM- 1 expression [(155+/-3.3 vs. 116+/-0.7) (P = 0.001)] and IL-1beta supernatant concentrations [(3.4+/-0.3 vs. 2.6+/-0.1) (P = 0.01)] in controls compared to aprotinin-treated endothelial cell preparation (n = 3). CONCLUSIONS: Hypoxia-reoxygenation-induced upregulation of neutrophil CD11b, endothelial cell ICAM-1 expression and IL-1beta concentrations is decreased by aprotinin at clinically relevant concentrations.