目的 制備載高良姜素（Gal）聚乙二醇-聚乳酸羥基乙酸共聚物（PEG-PLGA）納米粒（Gal-PEG-PLGA NPs），研究其對脂多糖（LPS）誘導的小鼠炎癥性肺損傷的治療作用。方法 采用乳化-溶劑揮發(fā)法將Gal包裹于納米粒中，單因素考察初步優(yōu)化處方及制備工藝，并進行表征。將35只SPF級小鼠隨機分為對照組、模型組（5 mg·kg^-1 LPS）、空白納米粒組、游離型Gal（8 mg·kg^-1）組和Gal-PEG-PLGA NPs低、中、高劑量（0.5、2、8 mg·kg^-1）組，每組5只。對照組給予相同體積0.9%氯化鈉溶液，其余動物ip 5 mg·kg^-1 LPS，1 h后ip給藥。24 h后，進行小鼠活體成像，并取出肺組織進行蘇木素-伊紅（HE）染色觀察肺組織病理變化；通過檢測肺組織中中性粒細胞髓過氧化物酶（MPO）活性，評估中性粒細胞的組織浸潤情況；實時熒光定量PCR（qRT-PCR）法檢測肺組織炎癥因子Il-1b、Il-6、Tnf-α mRNA表達；免疫印跡法檢測VE-cadherin、β-catenin蛋白表達。結果 單因素實驗確定的最優(yōu)處方為： PEG-PLGA用量60 mg，有機相Gal用量15 mg，水相PVA質量濃度為20 mg·mL^-1，水相體積為10 mL，水相與有機相體積比8∶1。依據(jù)此處方制備的Gal-PEG-PLGA NPs呈圓球狀，粒徑（114.00±8.54）nm，多分散指數(shù)為0.166±0.010；$\zeta$電位為（-10.67±2.08）mV。HE染色結果表明，與模型組相比，GalPEG-PLGA NPs中、高劑量（2、8 mg·kg^-1）組，非氣管細胞數(shù)量顯著降低（P＜0.01），且呈現(xiàn)劑量相關性，肺組織中MPO活性顯著降低（P＜0.01），Il-1b、Il-6、Tnf-α mRNA相對表達量顯著降低（P＜0.01），VE-cadherin和β-catenin蛋白表達水平顯著提高（P＜0.01）。結果表明2、8 mg·kg^-1的Gal-PEG-PLGA NPs能夠有效抑制小鼠肺部炎癥細胞浸潤，減少血管滲出，降低炎癥因子基因表達，保護內皮細胞屏障。結論 Gal-PEG-PLGA NPs可顯著減輕小鼠炎癥性肺損傷，有望進一步開發(fā)為靶向治療肺損傷的藥物載體。

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

國家自然科學基金資助項目（81300059）