肺泡巨噬细胞ADAR1基因在急性肺损伤中表达的变化

目的:观察肺泡巨噬细胞(alveolar macrophag-es,AMs)RNA腺苷脱氨酶1(adenosine deaminase act-ing on RNA,ADAR1)基因(ADAR1基因)在急性肺损伤中的变化,探讨该基因在急性肺损伤病理变化中可能发挥的作用。方法:采用气管内滴注脂多糖(li-popolysaccharides,LPS)的方法制备急性肺损伤模型,经瑞氏染色计数急性肺损伤大鼠肺泡灌洗液中AMs、中性粒细胞(polymorphonuclear leukocytes,PMNs)并计算各自所占比例;以RT-PCR方法观察ADAR1基因在急性肺损伤中表达的变化。结果:气管内滴注脂多糖(2.5 mg.kg-1)成功制备的急性肺损伤模型中,肺泡灌洗液中细胞总数随时间变化而变化,由对照组的1.74×106增加至炎症反应6 h时17.13×106,9 h时17.00×106。AMs所占细胞总数的比例则由98%下降为21%,而其绝对数量随时间的推移不断的上升,尤其以6 h和9 h为著。ADAR1基因在急性肺损伤肺泡巨噬细胞中呈现时间依赖性的升高。结论:内毒素诱导的急性肺损伤模型中,AMs绝对数量显著上升,且其中ADAR1基因表达呈时间依赖性的升高,提示ADAR1基因可能在急性肺损伤发病过程及病理发展中发挥了重要的作用。     

肺泡巨噬细胞与全氟异丁烯所致急性肺损伤

目的　全氟异丁烯 (PFIB)是一种具有强大肺杀伤作用、可穿透防毒面具的潜在性化学战剂。其毒性作用机制目前尚未完全阐明。本研究拟就肺泡巨噬细胞 (AM)在PFIB急性吸入性肺损伤中的作用进行初步探讨。方法　雄性昆明小鼠 ,随机分为 4组 ,即对照组、氯化钆 (GdCl3)组、PFIB组和GdCl3/PFIB组。其中PFIB和GdCl3/PFIB组分别在中毒前4 8h及 2 4h各尾静脉iv 10mg·kg- 1GdCl31次 ,对照与PFIB组给予等剂量生理盐水。之后对照组与GdCl3组进行过滤空气暴露 ,PFIB组与GdCl3/PFIB组进行全身暴露PFIB中毒 ,PFIB中毒剂量为 130mg·m- 3× 5min。分别在中毒结束后 8,12 ,2 4 ,4 8和72h ,测定支气管肺泡灌洗液 (BALF)中总蛋白含量及肺组织湿 /干重比 ;在中毒结束后 2 4h观察组织及超微病理改变 ;并观察在 190mg·m- 3× 5min中毒剂量下小鼠 7d内的死亡率。结果　预先抑制AM功能可显著降低PFIB中毒小鼠死亡率 (P <0 .0 5 ) ,改善PFIB所致的肺组织及超微病理改变 ;在中毒后 8,12 ,2 4h ,可显著降低BALF中总蛋白含量(与相应时间点的PFIB组比较 ,P <0 .0 5 ) ,明显降低肺湿 /干重比 (其中 8,2 4h与相应时间点的PFIB组比较 ,P <0 .0 1;12h与PFIB组比较 ,P <0 .0 5 )。以上各时点的BALF中总蛋白含量与正常对照组比较显著升高     

肺泡巨噬细胞在脓毒症急性肺损伤中的作用

肺脏是脓毒症中常受累的脏器之一．肺损伤时中性粒细胞在肺内浸润、聚集,在肺损伤中起主要作用。肺泡巨噬细胞具有防御吞噬功能。同时分泌趋化因子、细胞因子和其他炎性介质参与中性粒细胞在肺内的迁移过程。我们观察了趋化因子巨噬细胞炎性蛋白-2（MIP-2）和肺泡巨噬细胞在中性粒细胞肺内迁移过程中的作用及抗MIP-2和核因子（NF）-κB抑制剂N-乙酰半胱氨酸（NAC）的肺保护作用。     

肺泡巨噬细胞在肺损伤机理中的作用

肺泡巨噬细胞在病理情况下有较强的组织损伤作用。它通过激活后释放多种生物活性物质而造成肺损伤。本文重点阐述肺泡巨噬细胞释放生物活性物质的种类及其在呼吸窘迫综合征、(ARDS)间质性肺疾病肺纤维化、肺气肿以及矽肺等肺损伤机理中的作用。     

莰醇对脂多糖诱导急性肺损伤的保护作用研究

目的探讨莰醇(broneol)在脂多糖(lipopolysaccharide,LPS)诱导的急性肺损伤(acute lung injury,ALI)中的作用。方法 C57♂小鼠随机分为生理盐水组、模型组、莰醇组、地塞米松组,气道内滴入LPS制备ALI模型。LPS滴入后6、12、24 h,测定肺泡灌洗液(BALF)中肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)、白介素-6(IL-6)、角化生长因子(KC)等含量,观察肺组织病理学改变。LPS刺激小鼠肺泡巨噬细胞(MHS)和上皮细胞(MLE-12),1、3、6、9、12、24 h后,测定MHS中TNF-α、IL-6含量及MLE-12中KC值、巨噬细胞炎症蛋白-2(MIP-2)含量。结果莰醇可明显抑制TNF-α、KC、IL-1β的分泌,对IL-6的早期作用不明显,但用药后24 h有一定后期效应。莰醇在6、12 h时间点,可明显改善肺组织病理学变化。莰醇对MHS细胞分泌TNF-α没有明显影响,对IL-6的分泌抑制作用后期更明显,对MLE-12细胞分泌KC和MIP2的抑制作用在LPS刺激后期均明显。结论莰醇对LPS诱导的ALI有保护作用,其作用机制可能与抑制相关炎症因子的释放、抑制相关炎症细胞的活化和中性粒细胞的聚集有关。     

肠缺血再灌注大鼠肺损伤时NOS及肺泡巨噬细胞分泌NO的变化

本实验通过对大鼠肠缺血再灌注后巨噬细胞活化分泌ＮＯ及肺组织内ＮＯＳ的变化 进行观察,显示肠缺血再灌注组肺泡巨噬细胞分泌ＮＯ的水平及肺内ＮＯＳ的水平均显著高于假手术对照组,表明肠缺血再灌注肺内巨噬细胞的ｉＮＯＳ被激,大量合成并释放ＮＯ,其作用一方面可增强杀菌功能,另一方面导致肺组织损伤。     

乌司他丁对小鼠肺泡巨噬细胞TREM蛋白表达的影响研究

目的 研究乌司他丁对脂多糖(lipopoly saccharide,LPS)刺激后的小鼠肺泡巨噬细胞(AM)表面TREM蛋白表达的影响,并探讨乌司他丁在AM介导的炎症反应中的作用及机制.方法 培养肺泡巨噬细胞,分为对照组、LPS干预组、LPS+乌司他丁(LU)组.对照组不予处理,LPS干预组给予100 ng/mL LPS,LU组给予100ng/mL LPS+ 10 000 U/mL乌司他丁,之后分别在3h、12h、24 h用流式细胞仪(FACS)检测AM表面TREM1、TREM2蛋白的表达水平.ELISA检测AM培养上清液中TNF-α表达水平.结果 对照组TREM1、TREM2各时间点的表达差异无统计学意义(P＞0.05).LPS干预组TREM1的表达在3h上升到最高,24 h时接近正常;TREM2在3h下降到最低,之后上升.LU组TREM1的表达均明显下降,24h下降至最低,与LPS组对比差异有统计学意义(P＜0.05);TREM2的表达均明显升高,在24 h升至最高,与LPS组对比差异有统计学意义(P＜0.05).TNF-α的表达对照组各时间点差异无统计学意义(P＞0.05);LPS组在3h达到最高,之后下降,24 h时接近正常;LU组均明显下降,与LPS组对比差异有统计学意义(P＜0.05).结论 乌司他丁可能通过调节TREM蛋白在LPS致AM介导的炎症反应中起重要作用.     

脂多糖对肺泡巨噬细胞自噬水平的影响

目的观察脂多糖(LPS)诱导肺泡巨噬细胞(NR8383)后,对细胞自噬水平的影响。方法 将体外培养的NR8383细胞分成LPS处理组和磷酸盐缓冲液(PBS)对照组,培养8h后,采用酶联免疫吸附法(ELISA)检测细胞培养上清液中肿瘤坏死因子-α(TNF-α)蛋白水平,自噬体检测:采用实时荧光定量聚合酶链反应(real-time PCR)检测细胞LC3 mRNA的转录水平、采用Western blot检测细胞LC3Ⅱ/LC3Ⅰ蛋白水平。结果 LPS处理组细胞培养上清液中TNF-α含量(pg/ml)较PBS对照组明显升高(639.20±43.49 vs 6.47±1.23,P<0.01),细胞LC3 mRNA转录水平较PBS对照组上调(3.4±0.36倍,P<0.01),细胞LC3Ⅱ/LC3Ⅰ较PBS对照组升高(1.03±0.15 vs 0.53±0.12,P<0.01)。结论 LPS刺激NR8383细胞后,细胞自噬体形成增多,其可能参与了NR8383肺泡巨噬细胞的炎症反应调控。     

氨基胍对脂多糖诱导的大鼠肺表面活性物质和肺泡巨噬细胞的影响

目的观察氨基胍(aminogunidine,AG)对脂多糖(1ipopolysaccharide,LPS)诱导的大鼠肺表面活性物质(pulmonary surfactant,PS)时程性变化的影响和对肺泡巨噬细胞(alveolar macrophage,AM)的影响,探讨AG对肺损伤组织的保护作用及其机制。方法试验一:健康♂SD大鼠随机分为对照组、模型组和AG治疗组。模型组、AG治疗组静脉注射LPS(5mg·kg-1)复制内毒素性肺损伤模型。LPS3h和6h后腹腔注射AG(100mg·kg-1,AG治疗组)和生理盐水(对照组及LPS组)。原位杂交法(ISH)和Western blot法分别测定肺组织肺表面活性物质蛋白A(SP-A)mRNA及蛋白水平;留取肺泡灌洗液(BALF),测定BALF中的总磷脂(TPL)和总蛋白(TP)。试验二:体外分离培养大鼠肺泡巨噬细胞,以LPS(终浓度10mg·L-1)损伤巨噬细胞,观察AG对肺泡巨噬细胞的影响。结果与对照组比较,大鼠肺损伤后SP-A mRNA及蛋白表达在LPS6h、9h后明显下降;BALF中TPL明显减少,TP增多。肺损伤3h用AG治疗3h后,SP-A mRNA阳性细胞表达及蛋白明显增强,BALF中TPL较LPS组相同时间点明显上升,TP降低,病理显示肺损伤减轻。体外实验显示,与正常对照组相比,LPS处理巨噬细胞后,细胞培养上清中NO、TNF-α、IL-6和LDH浓度明显增高,AG明显减少LPS所致的LDH和NO的释放,降低TNF-α和IL-6浓度。结论肺损伤后早期给予AG可通过增强肺表面活性物质表达减轻内毒素性肺损伤。AG可抑制LPS对巨噬细胞的作用。     

Cyclic helix B peptide alleviates sepsis-induced acute lung injury by downregulating NLRP3 inflammasome activation in alveolar macrophages

Acute lung injury (ALI) exhibits high clinical morbidity and mortality rates. Our previous study has indicated that the novel proteolysis-resistant cyclic helix B peptide (CHBP) exerts an anti-inflammatory effect in mice with AKI. In the present study, we evaluated the effect of CHBP in an in vivo sepsis-induced ALI model and in vitro using lipopolysaccharide (LPS) and ATP stimulated bone marrow-derived macrophages (BMDMs). For in vivo experiments, mice were randomly divided into three groups: 1) sham; 2) LPS; and 3) LPS + CHBP (n = 6). All relevant data were collected after 18 h. Following CHBP treatment, the lung function of the mice was significantly improved compared to the LPS group. CHBP administration inhibited interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α production at both the protein and mRNA levels. Additionally, following CHBP treatment, the population of pulmonary macrophages decreased. Simultaneously, the proportion of caspase-1-activated alveolar macrophages was also decreased after CHBP treatment. The protein levels of NLRP3 and cleaved caspase-1 were attenuated in the lung tissue following CHBP treatment. In in vitro experiments, CHBP treatment decreased NLRP3 inflammasome expression and downstream IL-1β secretion, consistent with the in vivo results. In addition, CHBP reversed nuclear factor (NF)-κB and I-κB phosphorylation with a significant dose-dependent effect. Therefore, these findings suggest the potential of CHBP as a therapeutic agent in sepsis-induced ALI owing to inhibition of the NLRP3 inflammasome via the NF-κB pathway in macrophages.     

Cathepsin B and D activity in alveolar macrophages from rats with pulmonary granulomatous inflammation or acute lung injury

Cathepsin B and D activity was determined using specific synthetic substrates in alveolar macrophages (AMs) obtained from Sprague-Dawley rats with experimentally induced pulmonary granulomatous inflammation. Increased cathepsin B activity was found 4 days after intravenous injection of complete Freund's adjuvant (CFA), but not after injection of live bacillus Calmette-Guérin organisms (BCG), indicating that the enzyme response was unrelated to the subsequent development of granulomatous inflammation. Findings of comparable increases in enzyme activity following injection of mineral oil (MO) indicate that the response to CFA was due to the oil component. Significantly, oleic acid (OA), a natural fatty acid, did not stimulate enzyme activity although the agent, like MO, caused acute lung injury as assessed by 125I albumin uptake. At 7 and 28 days following injection of CFA, cathepsin B levels in AMs were the same as those in animals given normal saline (NS), although bronchoalveolar lavage (BAL) samples still contained increased numbers of AMs, and cells obtained at 28 days phagocytosed more polystyrene microspheres. Cathepsin D activity did not increase 4 days after injection of CFA or BCG + CFA; at 28 days following injection of BCG + CFA activity was significantly decreased as compared to animals given NS. The data reveal a differential response of two lysosomal enzymes during the early phases of granulomatous inflammation.     

热休克蛋白70在大鼠急性肺损伤中的表达

目的:探讨急性肺损伤(ALI)大鼠肺组织热休克蛋白70(HSP70)的表达。方法:雌性Wistar大鼠36只,随机分为两组:急性肺损伤组(A组)、对照组(B组),大鼠尾静脉注射脂多糖(LPS)复制ALI模型。所有的动物于注射LPS后2,4,6 h处死,测定肺组织HSP70的表达、超氧化物歧化酶(SOD)活性及丙二醛(MDA)的含量。结果:A组同B组相比,各时间点肺组织HSP70表达均增多,以2,6 h升高明显(P<0.01),MDA含量增高(P<0.05),SOD活性明显降低(P<0.05)。结论:HSP70在ALI后的表达增多可能与其参与LPS所致肺损伤后的组织保护有关。     

Malathion and phenthoate carboxylesterase activities in pulmonary alveolar macrophages as indicators of lung injury

Malathion and phenthoate carboxylesterase activities were investigated in pulmonary alveolar macrophages (PAM) in Sprague-Dawley rats. PAM was found to be capable of hydrolyzing phenthoate at a faster rate than malathion. Oral administration to rats with O,O,S-trimethyl phosphorothioate (OOS-Me), a pneumotoxic impurity present in technical grades of malathion and phenthoate, increased the activities of these esterases in PAM without affecting an activity in lung microsomal carboxylesterase. The time course study indicated that this increase was maximal on Day 1 following treatment with OOS-Me at 20 and 40 mg/kg of doses. To assess the usefulness of measuring these esterases in PAM as an indicator of lung damage, paraquat and bromobenzene were administered to rats with treatment regimens which have been shown previously to result in histopathologically demonstrable pneumotoxicity. Malathion and phenthoate carboxylesterase activities in PAM were increased by two- to threefold following treatment with paraquat or bromobenzene. These treatments also increased lung microsomal malathion carboxylesterase activity by threefold. Furthermore, infection of rats with Pseudomonas aeruginosa by intratracheal inoculation increased malathion and phenthoate carboxylesterase activities in PAM by two- to threefold without increasing these activities in lung microsomes. These results indicate that PAM may play a significant role in detoxifying airborne malathion and phenthoate when inhaled. Furthermore, the activities of malathion and phenthoate carboxylesterases may be useful for detecting lung injury produced by pneumotoxic chemicals as well as bacterial infection.     

银杏叶提取物注射液对脂多糖致大鼠急性肺损伤肺组织的保护作用

目的 观察银杏叶提取物注射液（GBE）对脂多糖（LPS）致大鼠急性肺损伤（ALI）肺组织的保护作用及其可能机制。方法 24只健康雄性Wistar大鼠随机分为对照组、LPS组和GBE组,每组8只。尾静脉注射LPS建立ALI模型,光镜下观察大鼠肺组织形态学改变;检测肺组织中超氧化物歧化酶活性（SOD）和丙二醛（MDA）含量及血清中白细胞介素-6（IL-6）的表达变化。结果 与对照组相比,LPS组肺组织中SOD活性降低、MDA含量增加、血清中IL-6含量增加（P<0.05）;应用GBE后,肺组织SOD活性升高、MDA含量减少、血清中IL-6含量减少（P<0.05）。结论 GBE可有效减轻ALI肺组织的炎症反应,其机制可能与其提高大鼠抗氧化能力、升高血清中IL-6的含量有关。     

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.     

Emodin attenuates severe acute pancreatitis-associated acute lung injury by suppressing pancreatic exosome-mediated alveolar macrophage activation

Severe acute pancreatitis-associated acute lung injury (SAP-ALI) is a serious disease associated with high mortality. Emodin has been applied to alleviate SAP-ALI; however, the mechanism remains unclear. We report that the therapeutic role of emodin in attenuating SAP-ALI is partly dependent on an exosomal mechanism. SAP rats had increased levels of plasma exosomes with altered protein contents compared to the sham rats. These infused plasma exosomes tended to accumulate in the lungs and promoted the hyper-activation of alveolar macrophages and inflammatory damage. Conversely, emodin treatment decreased the plasma/pancreatic exosome levels in the SAP rats. Emodin-primed exosomes showed less pro-inflammatory effects in alveolar macrophages and lung tissues than SAP exosomes. In detail, emodin-primed exosomes suppressed the NF-κB pathway to reduce the activation of alveolar macrophage and ameliorate lung inflammation by regulating PPARγ pathway, while these effects were amplified/abolished by PPARγ agonist/antagonist. Blockage of pancreatic acinar cell exosome biogenesis also exhibited suppression of alveolar macrophage activation and reduction of lung inflammation. This study suggests a vital role of exosomes in participating inflammation-associated organ-injury, and indicates emodin can attenuate SAP-ALI by reducing the pancreatic exosome-mediated alveolar macrophage activation.