目的 制备载高良姜素（Gal）聚乙二醇-聚乳酸羟基乙酸共聚物（PEG-PLGA）纳米粒（Gal-PEG-PLGA NPs），研究其对脂多糖（LPS）诱导的小鼠炎症性肺损伤的治疗作用。方法 采用乳化-溶剂挥发法将Gal包裹于纳米粒中，单因素考察初步优化处方及制备工艺，并进行表征。将35只SPF级小鼠随机分为对照组、模型组（5 mg·kg^-1 LPS）、空白纳米粒组、游离型Gal（8 mg·kg^-1）组和Gal-PEG-PLGA NPs低、中、高剂量（0.5、2、8 mg·kg^-1）组，每组5只。对照组给予相同体积0.9%氯化钠溶液，其余动物ip 5 mg·kg^-1 LPS，1 h后ip给药。24 h后，进行小鼠活体成像，并取出肺组织进行苏木素-伊红（HE）染色观察肺组织病理变化；通过检测肺组织中中性粒细胞髓过氧化物酶（MPO）活性，评估中性粒细胞的组织浸润情况；实时荧光定量PCR（qRT-PCR）法检测肺组织炎症因子Il-1b、Il-6、Tnf-α mRNA表达；免疫印迹法检测VE-cadherin、β-catenin蛋白表达。结果 单因素实验确定的最优处方为： PEG-PLGA用量60 mg，有机相Gal用量15 mg，水相PVA质量浓度为20 mg·mL^-1，水相体积为10 mL，水相与有机相体积比8∶1。依据此处方制备的Gal-PEG-PLGA NPs呈圆球状，粒径（114.00±8.54）nm，多分散指数为0.166±0.010；$\zeta$电位为（-10.67±2.08）mV。HE染色结果表明，与模型组相比，GalPEG-PLGA NPs中、高剂量（2、8 mg·kg^-1）组，非气管细胞数量显著降低（P＜0.01），且呈现剂量相关性，肺组织中MPO活性显著降低（P＜0.01），Il-1b、Il-6、Tnf-α mRNA相对表达量显著降低（P＜0.01），VE-cadherin和β-catenin蛋白表达水平显著提高（P＜0.01）。结果表明2、8 mg·kg^-1的Gal-PEG-PLGA NPs能够有效抑制小鼠肺部炎症细胞浸润，减少血管渗出，降低炎症因子基因表达，保护内皮细胞屏障。结论 Gal-PEG-PLGA NPs可显著减轻小鼠炎症性肺损伤，有望进一步开发为靶向治疗肺损伤的药物载体。

Objective To prepare galangin (Gal)-loaded polyethylene glycol-polylactic-co-glycolic acid (PEG-PLGA) nanoparticles (Gal-PEG-PLGA NPs) and investigate the therapeutic effect on lipopolysaccharide (LPS)-induced inflammatory lung injury in mice.Methods Gal was encapsulated in nanoparticles by the emulsion-solvent evaporation method. The optimal formulation and preparation process were preliminarily optimized by single-factor experiments and characterized. Thirty-five SPF mice were randomly divided into the control group, model group (5 mg·kg^-1 LPS), blank nanoparticle group, free Gal (8 mg·kg^-1) group, and Gal-PEG-PLGA NPs low, medium, and high-dose (0.5, 2, 8 mg·kg^-1) groups, with five mice in each group. The control group was given the same volume of 0.9% sodium chloride solution, and the other animals were intraperitoneally injected with 5 mg·kg^-1 LPS. One hour later, they were intraperitoneally administered the drugs. After 24 hours, in vivo imaging of the mice was performed, and lung tissues were taken for hematoxylin-eosin (HE) staining to observe the pathological changes of the lung tissues. The infiltration of neutrophils in the tissues was evaluated by detecting the activity of neutrophil myeloperoxidase (MPO) in the lung tissues. The expression of inflammatory factors Il-1b, Il-6, and Tnf-α mRNA in the lung tissues was detected by real-time fluorescence quantitative PCR (qRT-PCR). The expression of VE-cadherin and β-catenin proteins was detected by Western blotting.Results The optimal formulation determined by single-factor experiments was as follows: PEG-PLGA dosage 60 mg, organic phase Gal dosage 15 mg, water phase PVA mass concentration 20 mg·mL^-1, water phase volume 10 mL, water phase to organic phase volume ratio 8∶1. The Gal-PEG-PLGA NPs prepared according to this formulation were spherical, with a particle size of (114.00 ± 8.54) nm, a polydispersity index of 0.166 ± 0.010, and a ζ potential of (-10.67 ± 2.08) mV. The HE staining results showed that compared with the model group, the number of non-tracheal cells in the medium and high-dose (2, 8 mg·kg^-1) Gal-PEG-PLGA NPs groups was significantly reduced (P<0.01), and there was a dose-dependent relationship. The MPO activity in the lung tissues was significantly reduced (P<0.01), and the relative expression levels of Il-1b, Il-6, and -α mRNA were significantly decreased (P<0.01). The expression levels of VE-cadherin and β-catenin proteins were significantly increased (P<0.01). These results indicated that Gal-PEG-PLGA NPs with a concentration of 2, 8 mg·kg^-1 could effectively inhibit the infiltration of inflammatory cells in the lungs of mice, reduce vascular leakage, lower the expression of inflammatory factor genes, and protect the endothelial cell barrier.Conclusion Gal-PEG-PLGA NPs can significantly alleviate inflammatory lung injury in mice and are promising as a drug carrier for targeted treatment of lung injury.

R285.5

国家自然科学基金资助项目（81300059）