肽转运载体2 mRNA在脂多糖致急性肺损伤大鼠肺组织中的表达(英文)

目的研究肽转运载体(PEPT)2 mRNA在脂多糖(LPS)致急性肺损伤大鼠肺组织的表达。方法健康雄性SD大鼠分为正常对照组,生理盐水组,LPS 0.5mg·kg-12,4和8h组。光镜下观察肺组织病理变化,测定肺湿/干重比、支气管肺泡灌洗液(BALF)中蛋白含量和肺组织髓过氧化物酶(MPO)活性;半定量RT-PCR检测肺组织PEPT2 mRNA表达。结果气管内给予LPS 0.5mg·kg-1,大鼠肺组织呈现典型的炎症病理变化,如肺泡充血、出血、水肿、中性粒细胞浸润、肺泡壁增厚和透明膜形成等。LPS 2,4和8h组大鼠肺湿/干重比(4.72±0.18,5.06±0.17和5.12±0.16)明显高于正常对照组和生理盐水组(4.12±0.15和4.14±0.11)。与正常对照组和生理盐水组〔(1.26±0.12)和(1.25±0.07)U·g-1湿组织〕相比,LPS2,4和8h组大鼠肺MPO活性〔(1.96±0.15),(2.23±0.10)和(2.34±0.12)U·g-1湿组织〕明显增高。LPS 2,4和8h组大鼠BALF中蛋白含量〔(36.6±2.9),(86.9±3.5)和(92.2±2.7)mg·L-1〕明显高于正常对照组和生理盐水组〔(29.3±1.3)和(29.4±2.7)mg·L-1〕。LPS各组大鼠肺组织PEPT2 mRNA的表达水平与正常对照组和生理盐水组相比无明显变化。结论PEPT2 mRNA在LPS致急性肺损伤大鼠肺组织中的表达水平无明显变化。     

地昔帕明对小鼠内毒素急性肺损伤的影响

目的探讨地昔帕明(DP)对脂多糖(LPS)引起的急性肺损伤的作用并初步探讨其作用机制。方法昆明种小鼠随机分为生理盐水对照组(NS组)、地昔帕明对照组(DP组)、模型组(LPS组)及地昔帕明处理组(DP+LPS组)。腹腔注射LPS建立小鼠急性肺损伤模型。造模6h后测定肺湿/干重比值(W/D)、肺泡灌洗液(BALF)中白细胞数和蛋白含量、肺组织匀浆中髓过氧化物酶(MPO)活性和丙二醛(MDA)水平,同时用ELISA法检测肺匀浆中肿瘤坏死因子-α(TNF-α)含量。结果LPS可提高小鼠肺W/D、BALF中白细胞数和蛋白含量、肺匀浆MPO活性、MDA和TNF-α含量(P<0.01),DP处理组可有效减轻LPS所引起的上述变化(P<0.05)。结论DP对LPS导致的小鼠急性肺损伤有保护作用,其保护机制可能与抑制肺TNF-α的产生,进而减轻中性粒细胞的肺部扣押和肺组织脂质过氧化损伤的程度有关。     

西地那非对脂多糖诱导的小鼠急性肺损伤的作用

目的明确西地那非对急性肺损伤(ALI)的治疗作用及可能机制。方法采用脂多糖(LPS,4 mg·kg~(-1))气道滴入诱导的小鼠ALI模型。随机分为生理盐水组、LPS模型组、西地那非3,10及30 mg·kg~(-1)组、地塞米松5 mg·kg~(-1)组。测定肺干/湿重比值,常规细胞形态学检测支气管肺泡灌洗液(BALF)中白细胞,肺组织切片观察病理改变;测定肺组织匀浆髓过氧化酶(MPO)活性、NO含量、NOS活性及TNF-α含量。结果LPS诱导的ALI小鼠肺干/湿重比值明显下降;BALF中白细胞总数及中性粒细胞比例明显增加;肺毛细血管通透性明显增加;肺组织间隙大量中性粒细胞浸润和红细胞渗出;肺组织匀浆TNF-α含量和MPO活性明显增加,NO含量、总NOS活性及iNOS活性明显增加。同时腹腔注射西地那非可剂量依赖性地降低ALI小鼠肺干/湿重比值;减少BALF中的白细胞总数及中性粒细胞的比例;降低肺毛细血管通透性;改善肺组织病理变化;抑制肺组织匀浆TNF-α含量、MPO活性及NO含量、总NOS活性及iNOS活性的增加。结论西地那非对LPS诱导的ALI有保护作用,提示NO- cGMP途径可能在ALI中起重要作用。     

隐孔菌多糖对小鼠内毒素性肺损伤的保护作用

目的研究隐孔菌多糖(cryptoporus polysaccharide,CP)对脂多糖(LPS)诱导小鼠急性肺损伤(ALI)的影响。方法LPS气管内滴入诱导小鼠ALI模型,设立对照组、模型组、隐孔菌多糖(1、10、30mg·kg-1)组和地塞米松(0·5mg·kg-1)组,检测支气管肺泡灌洗液(BALF)和肺组织中中性粒细胞的浸润情况、比色法测定伊文氏兰渗出量及BALF中的中性粒细胞髓过氧化物酶(MPO)、超氧根阴离子自由基(O2·)含量,观察肺组织病理及肺湿重/干重比值改变,ELISA法检测肺组织中TNF-α和IL-10含量。结果隐孔菌多糖(1、10、30mg·kg-1)尾静脉给药能够抑制BALF MPO活性,改善ALI小鼠BALF及肺组织中的炎症细胞的聚集和肺水肿程度,降低肺组织中TNF-α水平及升高IL-10/TNF-α比值。结论隐孔菌多糖通过抑制中性粒细胞黏附、趋化、减轻肺水肿等改善LPS诱导的小鼠ALI。     

甘草酸单铵对脂多糖致小鼠急性肺损伤的保护作用

采用脂多糖(lipopolysaccharide，LPS)气道滴入诱导小鼠急性肺损伤(acute lung injury，ALI)模型，研究甘草酸单铵(monoammonium glycyrrhizinate，MAG)对ALI的防治作用及其机制。雄性ICR小鼠随机分为生理盐水(NS)对照组、MAG 3、10 及30 mg·kg^-1组、LPS组、地塞米松(dexamethasone，DXM) 5 mg·kg^-1组。MAG各组气道滴入LPS前1 h及滴入后3 h各给药1次，DXM组气道滴入LPS前1 h给药1次。LPS气道滴入后6 h处死动物，测定各组的肺湿重/干重比、肺通透性、肺组织中性粒细胞髓过氧化物酶(myeloperoxidase，MPO)含量、ELISA法检测肺组织匀浆TNF-α、IL-10含量，常规细胞形态学检测中性粒细胞在支气管肺泡灌洗液(bronchoalveolar lavage fluid，BALF)中的比例和肺组织病理改变。结果表明，MAG剂量依赖性减轻气道内滴入LPS诱导的小鼠ALI程度，降低肺湿重/干重比及肺组织伊文斯蓝的渗出，降低BALF中白细胞总数和中性粒细胞数比例，抑制组织MPO的释放，降低肺组织匀浆TNF-α的含量，增加肺组织IL-10的释放。以上结果提示，MAG可能通过调节TNF-α/IL-10的平衡而有效保护脂多糖诱导的急性肺损伤。     

脂多糖致急性肺损伤后Bax/Bcl-2变化

目的观察脂多糖(LPS)致大鼠急性肺损伤(ALI)后大鼠肺泡上皮细胞凋亡情况。方法雄性Wistar大鼠200~250g60只,随机分为两组,分别为对照组和LPS组,每组30只。各组分别注射0·9%氯化钠(NS)或LPS5mg/kg4h后观察呼吸频率,行动脉血气分析;致死后检测肺组织湿/干(W/D)比值,检测肺泡上皮细胞B-细胞淋巴瘤/白血病-2(Bcl-2)、Bcl-2相关X蛋白(Bax)表达。结果LPS组呼吸频率[(108±77)次/min]较对照组[(71±5)次/min]显著增快,且有明显的肺水肿和低氧血症。LPS组Bax蛋白表达阳性细胞率[(6·27±0·84)%]与对照组[(0·48±0·52)%]相比显著增高,Bcl-2蛋白表达阳性细胞率与对照组比较差异无统计学意义。结论促进细胞凋亡的Bax蛋白表达细胞显著增多,使Bax/Bcl-2细胞比例明显增加,可能参与了LPS诱发的ALI的发病机制。     

咯利普兰对脂多糖诱导的小鼠急性肺损伤的抑制作用

目的探讨磷酸二酯酶4(PDE4)抑制剂治疗急性肺损伤的作用机制。方法气道内滴入脂多糖3 mg.kg-1制备小鼠急性肺损伤模型,10 min后一次性ip不同剂量咯利普兰或地塞米松;同时设假手术和模型组。给药6 h后处死小鼠,观察肺湿重/干重比值和肺组织的病理改变;用细胞形态学方法计数支气管肺泡灌洗液(BALF)中白细胞和中性粒细胞;考马斯亮蓝法测定BALF总蛋白含量;髓过氧化物酶(MPO)活性测定试剂盒测定肺组织匀浆MPO活性;ELISA法测定肺组织匀浆肿瘤坏死因子α(TNF-α)含量;高效液相色谱法测定肺组织匀浆中cAMP-PDE和PDE4活性。结果小鼠气道内滴入脂多糖6 h后,与假手术组比较,模型组肺湿重/干重比值明显升高;肺组织病理观察可见肺血管和气道周围有大量中性粒细胞浸润;BALF中白细胞和中性粒细胞增多,蛋白含量增加;肺组织MPO活性、TNF-α水平、cAMP-PDE和PDE4活性升高。与模型组比较,咯利普兰(0.1,0.3及1.0 mg.kg-1)和地塞米松(0.5 mg.kg-1)可降低肺组织湿重/干重比值,降低BALF中白细胞总数、中性粒细胞数目和蛋白含量,改善肺组织病理变化,肺组织中MPO活性、TNF-α含量、cAMP-PDE和PDE4活性亦明显降低。结论咯利普兰治疗急性肺损伤的作用机制可能与抑制PDE4活性、抑制中性粒细胞黏附和趋化及降低TNF-α水平有关。     

吸入不同浓度一氧化氮对急性肺损伤小鼠肺组织炎症反应的影响

目的　探讨吸入一氧化氮 (NO)对急性肺损伤 (ALI)小鼠肺组织炎症反应的影响。方法　脂多糖 (LPS)腹腔注射诱导小鼠ALI模型 ,吸入不同浓度NO ,测定肺组织核因子 (NF) κB活性及肿瘤坏死因子 (TNF)α、白介素 (IL) 1 0mRNA的表达。结果　与LPS组 (A组 )比较 ,LPS +吸入NO 5 ppm(B组 )、LPS +吸入NO 2 0 ppm(C组 ) 1 2小时湿重 /干重 (W /D)显著降低 ,LPS +吸入NO4 0ppm(D组 )无明显差异。LPS注射后肺组织NF κB活性明显增强 ,6小时达到峰值 4 0 6± 6 2 ,显著高于LPS注射前 (45± 31 ,P <0 0 5 )。吸入NO 5 ppm和 2 0 ppm 6小时后 ,NF κB活性明显低于LPS组 (P <0 0 5 )。但吸入 4 0ppmNF κB活性在 3小时、6小时明显下降后 ,1 2小时又明显升高。B组和C组肺组织TNF α和IL 1 0浓度及mRNA表达在 3～ 1 2小时均明显降低 ,但D组吸入NO 4 0 ppm1 2小时 ,TNF α表达与LPS组无显著差异。吸入NO后各组IL 1 0表达均降低。结论　吸入 5 ppm和 2 0ppmNO可抑制LPS介导的NF κB活化 ,下调炎症因子表达 ,改善ALI ,但吸入 4 0 ppmNO加重肺损伤。     

硫酸甲基异硫脲对急性肺损伤小鼠肺组织核因子-κΒ活性的影响

目的　探讨硫酸甲基异硫脲 (SMT)对急性肺损伤小鼠肺组织核因子 (NF) κΒ活性的影响。方法　利用腹腔内注射内毒素 (LPS)诱导小鼠急性肺损伤模型 ,180只小鼠随机分为LPS组、LPS +SMT组 (LPS注射前腹腔内注射SMT2 0mg/kg) ,LPS注射后 0h、1h、3h、6h、12h迁移率改变电泳法 (EMSA)检测肺组织NF κΒ活性 ,同时测定肺组织中肿瘤坏死因子 (TNF)α、白介素 10 (IL 10 )浓度及其mRNA表达 ,并观察肺组织的病理改变。结果　与LPS组比较 ,1～ 12hSMT组肺组织核蛋白NF κΒ活性明显增强 (P <0 0 5 ) ;肺组织匀浆细胞因子TNFα及其mRNA表达显著增高(P <0 0 5 )。与LPS组比较 ,SMT组IL 10及其mRNA表达均明显下降。结论　SMT通过活化NF κΒ ,启动炎症因子表达 ,但同时抑制抗炎介质的表达 ,加重肺损伤     

硫化氢供体对Apo E基因敲除小鼠动脉粥样硬化的调节作用

目的探讨硫化氢(H2S)供体对Apo E基因敲除小鼠(Apo E-/-)动脉粥样硬化的调节作用。方法6wk龄正常C57BL/6J和Apo E-/-小鼠分为正常对照组、ApoE-/-组和Apo E-/-+硫氢化钠(NaHS)组,每组各8只,普通饮食饲养至16wk龄。分别观察各组小鼠血清中总胆固醇(TCHO)、低密度脂蛋白(LDL-C)和高密度脂蛋白(HDL-C)含量及主动脉根部斑块面积的变化;用硫电极法测定血清中H2S的含量。结果与对照组相比,Apo E-/-小鼠血清中TCHO[(12.59±3.11vs2.32±0.40)μmol·L-1]和LDL-C[(1.33±0.43vs0.13±0.03)μmol·L-1]水平明显升高,而HDL-C水平[(0.45±0.13vs1.49±0.21)μmol·L-1]明显降低,血清中H2S的含量[(44.64±4.52)μmol·L-1]较对照组[(57.69±7.03)μmol·L-1]明显下降,主动脉根部明显出现斑块[(139316.6±30362.93vs0)μm2];给予NaHS后,Apo E-/-小鼠血清中TCHO、LDL-C和HDL-C水平无明显变化,而血清中H2S的含量明显升高[(52.21±7.24vs44.64±4.52)μmol·L-1],主动脉根部动脉粥样硬化斑块明显缩小[(85927.84±1922.73vs139316.6±30362.93)μm2]。结论新型气体信号分子H2S可以延缓动脉粥样硬化的进程,缩小动脉粥样硬化斑块形成。     

Standardized myrtol attenuates lipopolysaccharide induced acute lung injury in mice

Context: Standardized myrtol, an essential oil containing primarily cineole, limonene and α-pinene, has been used for treating nasosinusitis, bronchitis and chronic obstructive pulmonary disease (COPD).

Objective: To investigate the effects of standardized myrtol in a model of acute lung injury (ALI) induced by lipopolysaccharides (LPS).

Materials and methods: Male BALB/c mice were treated with standardized myrtol for 1.5?h prior to exposure of atomized LPS. Six hours after LPS challenge, lung injury was determined by the neutrophil recruitment, cytokine levels and total protein concentration in the bronchoalveolar lavage fluid (BALF) and myeloperoxidase (MPO) activity in the lung tissue. Additionally, pathological changes and NF-κB activation in the lung were examined by haematoxylin and eosin staining and western blot, respectively.

Results: In LPS-challenged mice, standardized myrtol at a dose of 1200?mg/kg significantly inhibited the neutrophile counts (from 820.97?±?142.44 to 280.42?±?65.45, 10³/mL), protein concentration (from 0.331?±?0.02 to 0.183?±?0.01, mg/mL) and inflammatory cytokines level (TNF-α: from 6072.70?±?748.40 to 2317.70?±?500.14, ng/mL; IL-6: from 1184.85?±?143.58 to 509.57?±?133.03, ng/mL) in BALF. Standardized myrtol also attenuated LPS-induced MPO activity (from 0.82?±?0.04 to 0.48?±?0.06, U/g) and pathological changes (lung injury score: from 11.67?±?0.33 to 7.83?±?0.79) in the lung. Further study demonstrated that standardized myrtol prevented LPS-induced NF-κB activation in lung tissues.

Discussion and conclusion: Together, these data suggest that standardized myrtol has the potential to protect against LPS-induced airway inflammation in a model of ALI.     

Genipin alleviates LPS-induced acute lung injury by inhibiting NF-κB and NLRP3 signaling pathways

Genipin has been reported to have anti-inflammatory effect. However, its role on lipopolysaccharide (LPS)-induced acute lung injury (ALI) has not been explored. This study aimed to evaluate the effect of genipin on murine model of acute lung injury induced by LPS. The mice were treated with genipin 1 h before LPS administration. 12 h later, the myeloperoxidase (MPO) in lung tissues and lung wet/dry ratio were detected. The levels of TNF-α, IL-1β and IL-6 in bronchoalveolar lavage fluid (BALF) were measured by ELISA. Apart from this, we use western blot to detect the protein expression in the NF-κB and NLRP3 signaling pathways. The results showed that the treatment of genipin markedly attenuated the lung wet/dry ratio and the MPO activity. Moreover, it also inhibited the levels of TNF-α, IL-1β, IL-6 in the BALF. In addition, genipin significantly inhibited LPS-induced NF-κB and NLRP3 activation. In conclusion, these results demonstrate that genipin protected against LPS-induced ALI through inhibiting NF-κB and NLRP3 signaling pathways.     

Naringin attenuates acute lung injury in LPS-treated mice by inhibiting NF-κB pathway

Naringin has been reported as an effective anti-inflammatory compound. We previously showed that naringin had antitussive effect on experimentally induced cough in guinea pigs. However, the effects and mechanism of naringin on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice are not fully understood. In this study, our aim was to evaluate the anti-inflammatory activities of naringin on LPS-induced ALI in mice and clarify its underlying mechanisms of action. We found that in vivo pretreatment with naringin markedly decreased the lung wet weight to dry weight ratio, and led to significant attenuation of LPS-induced evident lung histopathological changes. Meanwhile, naringin significantly reduced bronchoalveolar lavage fluid (BALF) total cell and neutrophil (PMN) counts after LPS challenge. Furthermore, naringin inhibited myeloperoxidase (MPO: a marker enzyme of neutrophil granule) and inducible nitric oxide synthase (iNOS) activities in lung tissue and alleviated LPS-induced tumor neurosis factor-α (TNF-α) secretion in BALF in a dose-dependent manner. Additionally, Western blotting showed that naringin efficiently blunt NF-κB activation by inhibiting the degradation of I?B-α and the translocation of p65. Taken together, these results suggest that naringin shows anti-inflammatory effects through inhibiting lung edema, MPO and iNOS activities, TNF-α secretion and pulmonary neutrophil infiltration by blockade of NF-κB in LPS-induced ALI.     

Kaempferol regulates MAPKs and NF-κB signaling pathways to attenuate LPS-induced acute lung injury in mice

Recent studies show that mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-κB) signaling pathways are two pivotal roles contributing to the development of lipopolysaccharide (LPS)-induced acute lung injury (ALI). The present study aimed to investigate the protective effect of kaempferol (Kae), a naturally occurring flavonoid compound, on ALI and explore its possible mechanisms. Male BALB/c mice with ALI, induced by intranasal instillation of LPS, were treated or not with Kae (100mg/kg, intragastrically) 1h prior to LPS exposure. Kae treatment attenuated pulmonary edema of mice with ALI after LPS challenge, as it markedly decreased the lung W/D ratio of lung samples, protein concentration and the amounts of inflammatory cells in BALF. Similarly, LPS mediated overproduction of proinflammatory cytokines in BALF, including TNF-α, IL-1β and IL-6, was strongly reduced by Kae. Histological studies demonstrated that Kae substantially inhibited LPS-induced alveolar wall thickness, alveolar hemorrhage and leukocytes infiltration in lung tissue with evidence of reduced myeloperoxidase (MPO) activity. Kae also efficiently increased superoxide dismutase (SOD) activity of lung sample when compared with LPS group, which was obviously reduced by LPS administration. In addition, Western blot analysis indicated that the activation of MAPKs and NF-κB signaling pathways stimulated by LPS was significantly blocked by Kae. Taken together, our results suggest that Kae exhibits a protective effect on LPS-induced ALI via suppression of MAPKs and NF-κB signaling pathways, which may involve the inhibition of tissue oxidative injury and pulmonary inflammatory process.     

吡拉米司特在大鼠急性肺损伤模型中降低PDE4活性与TNF-α/IL-10平衡有关

目的观察PDE4活性与TNF-α/IL-10平衡在脂多糖(LPS)诱导的大鼠急性肺损伤模型(ALI)中相互关系,探讨选择性磷酸二酯酶4抑制剂吡拉米司特(piclamilast)对ALI的作用及机制。方法脂多糖(LPS)诱导大鼠ALI模型,设对照组、模型组、吡拉米司特组(1、3、10mg.kg-1)和地塞米松组(1mg.kg-1),常规细胞形态学检测肺泡灌洗液(BALF)和肺组织中中性粒细胞的浸润情况,比色法测定BALF中超氧阴离子自由基(O2.)和中性粒细胞髓过氧化酶(MPO),ELISA法检测肺组织中TNF-α和IL-10含量,高效液相(HPLC)法测定肺组织中PDE4活性。结果①吡拉米司特(1、3、10mg.kg-1)灌胃给予能够抑制BAL中MPO、O2.的增加,改善LPS诱导的大鼠ALI模型BALF中的炎症细胞聚集和肺水肿程度,②吡拉米司特可抑制LPS诱导的大鼠ALI肺组织TNF-α上升(P<0.05～0.01),并能明显提高LPS引起的大鼠ALI肺组织IL-10分泌下降,③大鼠ALI模型肺组织中PDE4活性明显上升(P<0.01),吡拉米司特预处理可抑制PDE4活性的上升,而且其对PDE4活性抑制性变化与TNF-α/IL-10比值的变化基本一致。地塞米松1mg.kg-1也能降低TNF-α和升高IL-10水平,调节TNF-α/IL-10平衡关系,但DXM不能抑制PDE4活性的升高。结论TNF-α/IL-10可能是ALI病理生理学的一对重要的平衡性细胞因子。吡拉米司特可能通过抑制PDE4活性,调节TNF-α/IL-10平衡改善LPS诱导的大鼠ALI。     

L6H9 attenuates LPS-induced acute lung injury in rats through targeting MD2

Acute lung injury (ALI) is a clinical syndrome characterized by respiratory failure and acute inflammatory response. Myeloid differentiation protein 2 (MD2) has been reported to play a pivotal role in the recognition of LPS and LPS-mediates inflammatory response. There have been no clinically effective therapeutic drugs for ALI. L6H9, an inhibitor of MD2, showed anti-inflammatory effects and cardiac protective activity. However, its effect on ALI has not been elucidated. In this study, intratracheal instillation of LPS was employed to induce ALI in rats. L6H9 pretreatment attenuates LPS-induced pathological variations in lung tissue and pulmonary edema. LPS instillation enhanced lung microvascular permeability, thereby causing inflammatory cells flow into bronchoalveolar lavage fluid (BALF). However, L6H9 inhibited the LPS-induced upregulation of total protein concentration and the number of inflammatory cells in BALF. In the meantime, macrophages infiltration in lung tissue induced by LPS was also mitigated by L6H9 treatment. Furthermore, L6H9 suppressed LPS-induced inflammatory cytokines expression in BALF, serum, and lung tissue. It is noteworthy that LPS-induced MD2/TLR4 complex formation was inhibited by L6H9 in lung tissue. On the whole, these results show that L6H9 can attenuate LPS-induced ALI in vivo by targeting MD2. Our study provide new candidate for the treatment of ALI.