壳寡糖减弱内毒素对小鼠巨噬细胞的损伤作用

目的观察壳寡糖对内毒素刺激的小鼠巨噬细胞(RAW 264.7)的影响。方法采用半定量RT-PCR检测IL-1β的基因水平变化,ELISA分析蛋白水平变化,流式细胞仪分析细胞凋亡情况。结果壳寡糖可显著抑制内毒素介导的炎症细胞因子IL-1β的增高,0.4 mg/mL的壳寡糖抑制效果最为明显,并显著降低内毒素介导的细胞凋亡。结论壳寡糖可显著保护内毒素介导的细胞损伤。     

当归、阿魏酸钠对急性炎性损伤的抑制效应及其与HIF-1α和VEGF表达的关系

目的 探讨当归制剂及其单体成分阿魏酸钠对脂多糖诱导的急性炎症反应的影响.方法 将50只ICR 小鼠随机分为5组,每组10只.采用脂多糖(LPS)配合卡介苗(BCG)注射法建立各炎症用药组和炎症对照组鼠炎性损伤模型,经腹腔分别注射当归制剂(A组)、阿魏酸钠(B组)、地塞米松(C组)、炎症对照组(D组)、正常对照组(E组).镜下观察小鼠肝、肺组织炎症反应情况,同时应用免疫组化法检测肝、肺组织中缺氧诱导因子1α(HIF-1α)和血管内皮生长因子(VEGF)蛋白的表达.结果 A、B、C组小鼠肝、肺的炎症反应明显弱于D组(P＜0.01),HIF-1α和VEGF表达也明显低于D组(P＜0.01).结论 当归、阿魏酸钠制剂均能显著抑制脂多糖诱导的肝、肺组织炎症反应. 其作用机制可能与抑制炎症组织中HIF-1α和VEGF蛋白的表达有关.     

壳寡糖对四氯化碳致急性肝损伤小鼠的保护作用

目的研究壳寡糖对四氯化碳(CCl4)诱导的化学性肝损伤小鼠的保护作用。方法小鼠随机分组,连续7d灌胃给予50,167,500mg.kg-1.d-1壳寡糖,于第7天腹腔注射四氯化碳制备小鼠急性肝损伤模型,检测血清丙氨酸氨基转移酶(ALT)和天门冬氨酸氨基转移酶(AST)活性;测定肝组织中丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性;采用光学显微镜观察肝脏组织形态学变化。结果中、高剂量的壳寡糖能明显抑制肝损伤小鼠血清ALT和AST活性的升高(P<0.05),抑制肝组织中MDA含量的升高(P<0.01),提高肝组织中SOD的活力(P<0.05),减轻CCl4对肝脏细胞的病理损伤。结论壳寡糖对四氯化碳造成的小鼠急性肝损伤具有一定的保护作用。     

丹酚酸B对肺上皮细胞凋亡和急性肺损伤的影响

目的探索丹酚酸B对肺上皮细胞凋亡和急性肺损伤的影响。方法采用Hoechst染色法和流式细胞法测定肺上皮细胞NCI-H292的凋亡率;采用内毒素脂多糖(LPS)诱导小鼠急性肺损伤炎症。结果 Hoechst染色显示丹酚酸B预处理对H2O2诱导NCI-H292细胞凋亡呈浓度依赖保护;流式细胞法测定显示与模型组对照,丹酚酸B作用后呈剂量依赖抑制H292细胞凋亡。整体试验发现丹酚酸B静脉注射均呈剂量依赖抑制LPS诱导的小鼠支气管肺炎症反应,减少支气管灌流液中白细胞总数、中性粒细胞和巨噬细胞。结论离体实验和整体实验证明丹酚酸B有明显的抗凋亡和抗炎作用,对进一步深入研究其治疗肺部炎症损伤的作用和机制具有重要意义。     

溶酶体组织蛋白酶B增加自噬保护缺氧诱导的心脏微血管内皮细胞损伤

目的探讨CTSB是否参与缺氧诱导的心脏微血管内皮细胞损伤。方法采用缺氧诱导内皮细胞损伤模型;分离CTSB基因敲除小鼠心脏微血管内皮细胞,采用腺病毒过表达CTSB,采用巴弗洛霉素阻断细胞自噬;采用ELISA法检测炎症因子的释放水平;采用TUNEL染色法检测细胞凋亡数量;采用caspase-3试剂盒检测细胞caspase-3的活性;细胞感染LC3-GFP-mCherry双标病毒,检测细胞自噬流的水平。结果CTSB基因敲除可明显加重缺氧诱导的内皮细胞炎症、凋亡,增加细胞自噬。CTSB过表达可减轻缺氧诱导的内皮细胞炎症、凋亡,增加细胞自噬。但是巴弗洛霉素处理可明显抵消CTSB过表达对细胞炎症、凋亡的抑制作用和对细胞自噬的保护作用。结论 CTSB基因敲除加重缺氧诱导的内皮细胞炎症和凋亡,而CTSB基因过表达减轻缺氧诱导的内皮细胞损伤。CTSB通过维持内皮细胞正常的自噬降解发挥作用。     

白藜芦醇对博莱霉素诱导的小鼠肺纤维化的作用

目的:探讨白藜芦醇(Res)对博莱霉素(BLM)致肺纤维化(PF)的治疗作用.方法:复制小鼠博莱霉素致PF模型,采用光镜观察组织学改变.测定肺组织羟脯氨酸(HyP)、超氧化物歧化酶(SOD)、丙二醛(MDA)以反映肺细胞损伤及PF的程度.结果:Res能显著降低实验性PF小鼠肺组织中Hyp、MDA的含量,显著提高小鼠肺组织的SOD活力.病理组织学检查亦表明,Rea能明显改善肺泡炎症程度和PF程度.结论:Res对实验性小鼠PF具有一定的治疗作用.     

壳寡糖通过p38MAPK糖基化修饰抑制TNF-α诱导的EA.hy926细胞IL-6、IL-8的表达

目的探讨壳寡糖对血管内皮细胞损伤的保护机制。方法以EA.hy926血管内皮细胞为研究对象,通过TNF-α刺激,建立高表达IL-6、IL-8的内皮细胞损伤模型。以RT-PCR和ELISA方法分别从mRNA和蛋白水平检测壳寡糖对IL-6、IL-8表达的影响。采用Western blot方法检测壳寡糖对p38MAPK信号通路及糖基转移酶(OGT)表达的影响。分析验证p38MAPK信号通路抑制剂和葡萄糖氨对TNF-α诱导的IL-6、IL-8表达的影响。结果成功建立了TNF-α诱导的高表达IL-6、IL-8的血管内皮细胞损伤模型。壳寡糖可从mRNA转录和蛋白翻译水平抑制IL-6、IL-8的表达。初步揭示壳寡糖对TNF-α诱导血管内皮细胞表达IL-6、IL-8的抑制作用可能是通过p38的磷酸化和O-连接糖基化相互作用来完成的。结论壳寡糖可通过OGT调控TNF-α诱导的EA.hy926细胞IL-6、IL-8的表达,保护血管内皮细胞,减少炎症损伤。     

褐藻胶寡糖对刀豆蛋白A诱导的急性肝损伤保护作用及机制初探

目的 研究褐藻胶寡糖对刀豆蛋白A (Concanavalin A, ConA)诱导急性肝损伤的保护作用及其可能的作用机制。方法 本实验以分子量为3kDa的甘露糖醛酸寡糖（M-3k）和古罗糖醛酸寡糖（G-3k）为受试样品,通过检测ConA注射后14h血清转氨酶水平及肝组织病理学评估肝脏损伤;通过酶联免疫法(ELISA) 检测TNF-α、IL-6水平;Western Blotting法检测Bcl-2、Bax蛋白表达。结果 与模型组相比,褐藻胶寡糖预防组显著降低了ConA急性肝损伤小鼠血清AST和ALT水平(P＜0.05),且组织病理学观察发现,肝细胞损伤、炎性浸润和凋亡程度减轻;与模型组相比,褐藻胶寡糖预防组显著降低了肝组织匀浆中促炎因子TNF-α、IL-6水平(P＜0.05);褐藻胶寡糖预防组Bcl-2蛋白表达明显高于模型组(P＜0.05),Bax蛋白表达水平明显低于模型组(P＜0.05)。讨论 说明褐藻胶寡糖对ConA诱导小鼠急性肝损伤具有一定保护作用,并且其作用机制可能部分与抑制肝脏炎症反应和干扰凋亡过程有关。     

水飞蓟宾对小鼠肝脏炎症损伤和肿瘤坏死因子的产生及活性的影响

建立了小鼠肝损伤模型及体内外肿瘤坏死因子(TNF)诱生的方法,研究水飞蓟宾(SB)对肝脏炎症损伤、TNF产生及其生物活性的影响。结果表明∶SB在体内外均可显著抑制脂多糖(LPS)诱导TNF产生;在体外能抑制TNF对肝细胞系GSG-7701和成纤维细胞系L929的细胞毒作用;在体内对LPS诱导的痤疮丙酸杆菌致敏的小鼠肝脏炎症损伤有保护作用。提示SB的保肝作用机理与其抑制TNF的产生和活性有关。     

热休克蛋白70肽段抑制胶原诱导关节炎小鼠Th17细胞生成

目的:研究HSP70肽段对CIA小鼠Th17细胞的影响,探讨其抑制CIA小鼠炎症损伤的机制。方法:将DBA/1小鼠随机分为HSP70肽段实验组、阴性对照组、结核菌素(PPD)对照组、阳性对照组。除阴性对照组外,其它各组小鼠用牛Ⅱ型胶原蛋白诱导关节炎。通过关节评分和病理改变评价病变程度。取外周淋巴结用流式细胞仪检测Th17细胞的数量,用实时定量PCR检测Th17细胞相关调控因子。结果:注射HSP70肽段的CIA小鼠其Th17细胞数量明显低于阳性对照组和PPD对照组,促进Th17细胞分化发育的相关因子IL-6、IL-23、TGF-β1、RORγt的表达水平低于阳性对照组和PPD对照组(P<0.05)。结论:HSP70肽段可调节Th17细胞分化的调控因子,抑制Th17细胞的分化,进而减轻CIA小鼠的炎症程度。     

DNA methyltransferase inhibitor alleviates bleomycin-induced pulmonary inflammation

Acute lung injury (ALI) is a severe disease characterized by several inflammatory responses in the lung with high mortality. We applied a mouse model of the pulmonary inflammation induced by the intratracheal instillation of bleomycin which is widely used to induce ALI and fibrosis in animal models. We hypothesized that DNA methyltransferase inhibitor, 5-azacytidine (5-Aza), with its anti-inflammatory benefits, might attenuate bleomycin-induced ALI through the alleviation of inflammation in the lung. We quantified white blood cells with cell blood count (CBC) test, lung inflammation by analyzing cells in the collected bronchoalveolar lavage fluid (BALF) and histological analysis of the lung tissues, and gene expression levels by real-time PCR. Intratracheal administration of bleomycin in mice induced pulmonary inflammation, characterized by increased neutrophil infiltration and inflammatory cytokine expression in the lungs. Mice treated with 5-Aza showed a significant reduction of lung neutrophilia, together with lower expressions of CXCL2 and MCP-1. Furthermore, 5-Aza treatment decreased the expression of proinflammatory cytokines in the lung tissue. Collectively, our data show that DNA methyltransferase inhibitor can alleviate the lung inflammation of bleomycin-induced ALI, indicating an alternative treatment option for the inflammation-triggered lung injury.     

表没食子儿茶素没食子酸酯对博莱霉素所致大鼠肺纤维化的干预作用及其机制研究

目的观察表没食子儿茶素没食子酸酯(EGCG)对实验性大鼠肺纤维化的干预作用及可能的作用机制。方法大鼠随机分为正常对照组、模型组、醋酸泼尼松组和EGCG大、中、小剂量组。通过气管内注入博莱霉素(BLM)复制大鼠肺纤维化模型,于造模后d 2各治疗组开始给药,给药后d7、14、28处死大鼠,取肺组织,观察形态学变化,并测定生化指标。结果EGCG能减少实验性肺纤维化大鼠肺组织中胶原沉积及降低肺系数(P<0.05,P<0.01),提高T-AOC、SOD水平(P<0.05,P<0.01),减轻肺部的病理损害。结论EGCG对BLM诱导产生的大鼠肺纤维化有一定的抑制作用。     

阻断IL-17A活化p50NF-κB抑制小鼠肺损伤引起的肺纤维化

探讨阻断IL-17A对小鼠肺损伤后肺纤维化发生的预防作用及其机制。博来霉素造成小鼠肺损伤7天后给予抗IL-17A中和性抗体治疗,第14天取材。利用HE和天狼星红染色法观察肺组织炎症及胶原沉积情况;利用生化检测试剂盒检测肺组织中羟脯氨酸及肺泡灌洗液中胶原含量;利用Kaplan-Meier法统计小鼠生存率;利用ELISA方法检测肺泡灌洗液中IL-17A、TGF-β1、IL-13、IFN-γ表达水平;利用免疫印迹分析方法检测肺组织中p65NF-κB、p50NF-κB、COX-2、5-LOX、15-LOX的表达或活化。结果显示:与模型对照组比较,阻断IL-17A能够降低胶原沉积、减少羟脯氨酸及胶原含量、提高小鼠生存率,并能抑制炎症反应,降低IL-17A、TGF-β1、IL-13,升高IFN-γ、COX-2、5-LOX、15-LOX表达水平,抑制p65NF-κB活化但促进p50NF-κB活化。结果提示,阻断IL-17A能预防肺损伤后肺纤维化发生,其机制与促进p50NF-κB活化及其下游分子表达、抑制急性炎症转变为慢性炎症反应有关。     

Ghrelin ameliorates bleomycin-induced acute lung injury by protecting alveolar epithelial cells and suppressing lung inflammation

Acute lung injury is a critical illness syndrome consisting of acute respiratory failure with bilateral pulmonary infiltrates that is refractory to current therapies. Acute lung injury is characterized by injury of the alveolar capillary barrier, neutrophil accumulation, and induction of pro-inflammatory cytokines followed by devastating lung fibrosis. Ghrelin, an acylated peptide produced in the stomach, increases food intake and growth hormone secretion, suppresses inflammation, and promotes cell survival. We investigated the pharmacological potential of ghrelin in the treatment of acute lung injury by using a bleomycin-induced acute lung injury model in mice. Ghrelin or saline was given to mice daily starting 1 day after bleomycin administration. Ghrelin-treated mice showed a definitively higher survival rate than saline-treated ones. They also had smaller reductions in body weight and food intake. The amelioration of neutrophil alveolar infiltration, pulmonary vascular permeability, induction of pro-inflammatory cytokines, and subsequent lung fibrosis were notable in ghrelin-treated mice. Additionally, ghrelin administration reduced the injury-induced apoptosis of alveolar epithelial cells. Our results indicate that ghrelin administration exerts a protective effect against acute lung injury by protecting the alveolar epithelial cells and regulating lung inflammation, and highlight ghrelin as a promising therapeutic agent for the management of this intractable disease.     

内毒素及博来霉素致急性肺损伤的病理改变异同及意义

目的探讨不同因素诱导的急性肺损伤病理改变的异同。方法分别采用内毒素及博来霉素诱导大鼠急性肺损伤模型,通过HE及MASSON染色观察不同时间肺组织病理学改变。结果2组在第3、7天均出现典型肺损伤改变,内毒素组在28d基本恢复正常,而后者则出现典型肺纤维化。结论2种因素诱导的模型虽然早期均有肺损伤,但最终结局不同,原因尚不清楚。     

Short courses of low dose dexamethasone delay bleomycin-induced lung fibrosis in rats

After comparing mortality and clinical signs in rats receiving different dexamethasone treatments, we investigated whether 0.5 mg/kg/d dexamethasone could delay pulmonary fibrosis induced by bleomycin and its time course (1, 3, 7, 14, 21 and 28 days). Tissue injury was assessed by apoptosis, lactate dehydrogenase (LDH) release, malondialdehyde content, and protein content; and inflammation was measured in terms of myeloperoxidase (MPO) activity, inflammatory cell count, and the mRNA expression of pro/inflammatory cytokines. Fibrogenic activity was analyzed by measuring the mRNA expression of fibrotic cytokines in tissue, and the promotion of fibroproliferation and synthesis of collagen type I by bronchoalveolar lavage fluids in vitro; and fibrosis was assessed by measuring the hydroxyproline content and collagen-I mRNA expression, and by histology. Bleomycin treatment induced tissue injury, inflammation and fibrogenic activity in lung, and led to fibrosis. Treatment with dexamethasone diminished the extent of fibrosis by strongly reducing inflammation, lung damage, and fibrogenic activity. These results demonstrate that the progression of bleomycin-induced pulmonary fibrosis in rats can be delayed by dexamethasone treatment, which appeared to alleviate not only inflammation but also lung damage and fibrogenic activity, indicating a possible new role for dexamethasone in the treatment of fibrosis.     

灯盏花素对实验性肺纤维化大鼠的干预作用

目的探讨灯盏花素对博莱霉素致肺纤维化大鼠肺组织细胞凋亡、Fas/FasL表达以及氧自由基的影响。方法48只大鼠随机分为对照组(16只)、模型组(16只)以及灯盏花素组(16只),气管内注入博莱霉素复制大鼠肺纤维化模型,次日灯盏花素组每日腹腔内注射灯盏花素注射液10mg.kg-1,于d7及d28每组分别处死8只大鼠,运用流式细胞仪测定肺纤维化大鼠肺组织细胞凋亡率、Fas/FasL表达,用TAB法测定肺组织匀浆丙二醛含量以及肺组织匀浆羟脯氨酸含量。结果炎症期和纤维化期大鼠肺组织细胞凋亡率增加,Fas/FasL表达增多,丙二醛及羟脯氨酸含量增高(P<0.01),而灯盏花素能明显降低肺组织的凋亡率,降低丙二醛及羟脯氨酸含量,下调Fas/Fasl的阳性表达。结论灯盏花素能减慢肺间质纤维化的进程,对肺间质纤维化有一定的保护作用。     

Effect of pravastatin on bleomycin‐induced acute lung injury and pulmonary fibrosis

1. Pravastatin is best known for its antilipidemic action. Recent studies have shown that statins have immunomodulatory and anti‐inflammatory effects. The present study aimed to determine whether or not pravastatin can attenuate acute lung injury and fibrosis in a mouse model. 2. Bleomycin was given to C57BL6 mice through intratracheal instillation. Pravastatin was given through intraperitoneal injection. To study the effect of pravastatin on the early inflammatory phase and the late fibrotic phase, mice were killed on days 3, 7, 14 and 21. 3. Pravastatin attenuated the histopathological change of bleomycin‐induced lung injury and fibrosis. The accumulation of neutrophils and increased production of tumor necrosis factor‐α in bronchoalveolar lavage fluid were inhibited in the early inflammatory phase. Pravastatin effectively inhibited the increase of lung hydroxyproline content induced by bleomycin. Furthermore, pravastatin reduced the increased expression of transforming growth factor (TGF)‐β1, connective tissue growth factor (CTGF), RhoA and cyclin D1. The increased levels of TGF‐β1 and CTGF mRNA expression were also significantly inhibited by pravastatin. 4. Pravastatin effectively attenuated bleomycin‐induced lung injury and pulmonary fibrosis in mice. Our results provide evidence for the therapeutic potential of pravastatin in the treatment of acute lung injury and pulmonary fibrosis.     

The specific free radical scavenger edaravone suppresses bleomycin-induced acute pulmonary injury in rabbits

1. Intratracheal instillation of bleomycin induces a condition in rabbits that serves as a useful model of human pulmonary fibrosis. Bleomycin-induced production of reactive oxygen species leads to acute lung inflammation and induction of apoptosis, which is followed by pulmonary fibrosis at a later chronic stage. In the present study, we tested whether edaravone, a free radical scavenger, would suppress bleomycin-induced acute pulmonary inflammation. 2. Rabbits were divided into three groups (n = 10 in each): (i) a bleomycin-treated group, which received intratracheal instillation of 2 mg/kg bleomycin; (ii) a bleomycin + edaravone group, which received a 10 day regimen of daily intravenous injections of edaravone (3 mg/kg per day) beginning 3 days before bleomycin instillation; and (iii) a saline control group. Rabbits were killed for analysis 7 days after bleomycin administration. 3. In lung tissues from the bleomycin-treated group, marked infiltration of inflammatory cells, consisting mainly of lymphocytes, neutrophils and eosinophils, was observed. In addition, significantly increased numbers of TUNEL-positive (apoptotic) and transforming growth factor-beta-positive cells were seen. All these effects were significantly attenuated by treatment with edaravone. 4. The findings of the present study suggest that edaravone may be useful in the prevention of acute lung injury resulting from the production of reactive oxygen species.     

The inhibition effect and mechanism of SY0916 on pulmonary fibrosis

SY0916 is a new platelet-activating factor receptor antagonist developed by our institute. In this study, the inhibitory effect of SY0916 on pulmonary fibrosis was investigated in epithelial–mesenchymal transition (EMT) induced by transforming growth factor beta 1 (TGF-β1) in vitro and a pulmonary fibrosis animal model induced by bleomycin (BLM). The results showed that SY0916 could inhibit the EMT of A549 cells induced with TGF-β1. In vivo, SY0916 administration significantly ameliorated the BLM-mediated histological changes, reduced main biochemical parameters related to pulmonary fibrosis such as hydroxyproline and glutathione, and also notably attenuated the expression of key pro-fibrotic mediator, TGF-β1. These findings demonstrated that SY0916 could possibly be developed as a promising candidate for the treatment of pulmonary fibrosis.