Nanomedicine for acute respiratory distress syndrome: The latest application,targeting strategy,and rational design

Acute respiratory distress syndrome (ARDS) is characterized by the severe inflammation and destruction of the lung air–blood barrier, leading to irreversible and substantial respiratory function damage. Patients with coronavirus disease 2019 (COVID-19) have been encountered with a high risk of ARDS, underscoring the urgency for exploiting effective therapy. However, proper medications for ARDS are still lacking due to poor pharmacokinetics, non-specific side effects, inability to surmount pulmonary barrier, and inadequate management of heterogeneity. The increased lung permeability in the pathological environment of ARDS may contribute to nanoparticle-mediated passive targeting delivery. Nanomedicine has demonstrated unique advantages in solving the dilemma of ARDS drug therapy, which can address the shortcomings and limitations of traditional anti-inflammatory or antioxidant drug treatment. Through passive, active, or physicochemical targeting, nanocarriers can interact with lung epithelium/endothelium and inflammatory cells to reverse abnormal changes and restore homeostasis of the pulmonary environment, thereby showing good therapeutic activity and reduced toxicity. This article reviews the latest applications of nanomedicine in pre-clinical ARDS therapy, highlights the strategies for targeted treatment of lung inflammation, presents the innovative drug delivery systems, and provides inspiration for strengthening the therapeutic effect of nanomedicine-based treatment.     

Surfactant protein-A in bronchoalveolar lavage fluid from neonates with RDS on conventional and high-frequency oscillatory ventilation

Surfactant protein-A (SP-A) was measured in bronchoalveolar lavage (BAL) samples from ventilated neonates in order to study the concentration of SP-A with regard to: 1) high-frequency oscillatory ventilation (HFOV) vs. conventional mechanical ventilation (CMV); 2) the postnatal course and ontogeny of SP-A; and 3) the correlation with measurements of pulmonary function. Patients on HFOV had markedly lower BAL SP-A concentrations on days 1 and 2 compared to those on CMV, which may indicate influence of mode of ventilation on surfactant metabolism. The SP-A concentrations increased postnatally concurrent with resolution of acute respiratory distress syndrome. Finally, there were only weak correlations between BAL SP-A concentration and dynamic lung compliance and oxygen requirement.     

Interaction of metal oxide nanoparticles with lung surfactant protein A

The alveolar lining fluid (ALF) covering the respiratory epithelium of the deep lung is the first biological barrier encountered by nanoparticles after inhalation. We here report for the first time significant differences for metal oxide nanoparticles to the binding of surfactant protein A (SP-A), the predominant protein component of ALF. SP-A is a physiologically most relevant protein and provides important biological signals. Also, it is involved in the lung’s immune defence, controlling e.g. particle binding, uptake or transcytosis by epithelial cells and macrophages. In our study, we could prove different particle-protein interaction for eight different nanoparticles, whereas particles of the same bulk material revealed different adsorption patterns. In contrast to other proteins as bovine serum albumin (BSA), SP-A does not seem to significantly deagglomerate large agglomerates of particles, indicating different adsorption mechanisms as in the well-investigated model protein BSA. These findings may have important consequences for biological fate and toxicological effects of inhaled nanomaterials.     

结核性和肺腺癌性胸腔积液中肺表面活性物质相关蛋白A、D的检测分析

目的探讨胸水中肺表面活性物质相关蛋白－A、D联合对原发性肺腺癌性与结核性胸腔积液的鉴别诊断价值。方法收集36例原发性肺腺癌性和28例结核性胸腔积液患者的胸水，采用 western blotting检测胸水中肺表面活性物质相关蛋白-A、D。结果原发性肺腺癌和结核性胸膜炎患者胸水中SP A光密度值分别为265.1±141.16和180.0±64.1；原发性肺腺癌和结核性胸膜炎患者胸水中SP-D光密度值分别为299.9±140.6和206.8±86.8。36例原发性肺腺癌患者中有23例胸水中SP-A＞250，有16例SP-D＞250，而SP-A＞250和（或）SP-D＞250有29例。28例结核性胸膜炎患者胸水中SP-A、SP-D均未超过250。结论肺表面活性物质相关蛋白A对结核性胸膜炎与原发性肺腺癌所致胸腔积液鉴别诊断有临床价值,联合肺表面活性物质相关蛋白D对两者的鉴别诊断更有意义。     

肺表面活性物质相关蛋白A与哮喘

本文综述了肺表面活性物质相关蛋白A（SP-A）与哮喘的关系。资料表明SP-A是构成肺表面活性物质（PS）的主要成分，在维持PS活性、肺泡和小气道的稳定，调节特异性免疫反应，减轻变态反应性肺损伤方面有重要作用，其功能改变与哮喘发病关系密切，具有重要的生物学意义。     

异丙酚对油酸性急性肺损伤大鼠肺表面活性蛋白A的影响

目的 观察油酸性急性肺损伤(ALI)大鼠肺组织肺表面活性蛋白A(SP-A)的蛋白表达情况及异丙酚对该指标的影响,探讨异丙酚肺保护作用及其机制.方法 80只雄性SD大鼠,体重250～290g,随机分成5组,每组16只:正常对照组(Ⅰ组),ALI组(Ⅱ组),异丙酚低剂量组(Ⅲ组):4mg·kg-1·h-1,异丙酚中剂量组(Ⅳ组):8mg·kg-1·h-1,异丙酚高剂量组(Ⅴ组):16mg·kg-1·h-1.静脉注射油酸250μl·kg-1制备大鼠ALI模型,Ⅲ～Ⅴ组持续静脉输注异丙酚4h之后处死大鼠.取每组8只大鼠肺组织,生化方法测定Na -K -ATP酶活性,RT-PCR测定肺组织SP-AmRNA蛋白表达;其余8只进行全肺支气管肺泡灌洗,留取支气管肺泡灌洗液(BALF),进行白细胞计数.结果 与Ⅰ组比较,Ⅱ组肺组织Na -K -ATP酶活性以及SP-AmRNA蛋白表达均显著减弱;BALF中白细胞数量及中性粒细胞比例均显著增加,淋巴细胞比例显著减少.给予不同剂量异丙酚治疗后(4、8、16mg·kg-1·h-1),与Ⅱ组比较,Ⅲ、Ⅳ、Ⅴ组肺组织Na -K -ATP酶活性均显著增强(P＜0.05),Ⅳ组肺组织SP-AmRNA蛋白表达显著增强(P＜0.05),Ⅴ组肺组织SP-AmRNA蛋白表达显著减弱(P＜0.05),Ⅲ组肺组织SP-AmRNA蛋白表达无显著变化;Ⅲ、Ⅳ、Ⅴ组BALF中白细胞数量及中性粒细胞比例均显著减少(P＜0.05),淋巴细胞比例显著增加 (P＜0.05).结论 异丙酚可以通过抑制油酸性ALI时肺组织的炎性反应,降低肺水肿程度,减轻肺泡Ⅱ型上皮细胞损伤,降低肺组织SP-A降解,促进肺泡SP-A合成与分泌,维持肺泡Ⅱ型上皮细胞正常的结构与功能,从而发挥对油酸性ALI的保护作用.     

芪蛭益肺颗粒对COPD大鼠模型SP-A表达和超微结构的影响

目的 探讨芪蛭益肺颗粒对慢性阻塞性肺疾病(COPD)大鼠模型肺表面活性物质相关蛋白A(SP-A)表达及肺组织超微结构的影响.方法 运用气管内滴注脂多糖加烟熏28 d法建立COPD大鼠模型,免疫组化法检测SP-A表达及透射电镜观察肺泡Ⅱ型上皮细胞超微结构变化.结果 与空白组比较,模型组大鼠SP-A表达明显减少,有显著差异(P<0.01),肺泡Ⅱ型上皮细胞超微结构不完整;与模型组比较,芪蛭益肺颗粒治疗组大鼠SP-A表达明显增强,差异显著(P<0.01),肺泡Ⅱ型上皮细胞超微结构完整.结论 芪蛭益肺颗粒可显著提高模型大鼠SP-A表达,改善细胞超微结构,对COPD的发生起到预防保护作用.     

中介素1-53对急性肺损伤大鼠SP-A及IL-18的影响

目的探讨脂多糖致急性肺损伤大鼠肺泡灌洗液（BALF）中表面蛋A（pulmonary surfactant associated protein A,SP-A）浓度及肺组织单核巨噬细胞中白介素18（interleukin 18,IL-18）的表达水平及中介素1-53（intermedin 1-53．IMD1-53）的影响。方法 将36只雄性Vistar大鼠随机分为正常组（A组）、急性肺损伤组（B组）、中介素1-53干预组（C组）,于2h,4h分别测定血气分析,后处死大鼠,测定肺组织湿／干比（W／D）、ELISA法检测BALF中SP-A的浓度、免疫组化法检测肺单核巨噬细胞内IL-18表达及各时间点肺组织病理变化。结果 与A组比较,B组动脉血PO2和BALF中SP-A浓度降低显著（P〈0．05）,湿干比及单核巨噬细胞中IL-18表达增加（P〈0．05）,肺组织充血水肿明显。与C组相比,上述改变得以逆转,肺损伤程度明显减轻（P〈0．05）。结论中介素1-53可通过抑制SP-A的减少和IL-18的生成在急性肺损伤早期起到一定的保护作用。