目的 考察黃芩苷脂質(zhì)體霧化吸入對急性呼吸窘迫綜合征（ARDS）小鼠肺損傷的保護(hù)作用，并探討其機(jī)制。方法 薄膜水化法制備黃芩苷脂質(zhì)體，并檢測包封率、載藥量、粒徑、Zeta電位、分散指數(shù)、累積釋放率。BALB/c小鼠隨機(jī)分為對照組、模型組、黃芩苷溶液（100 mg·kg^-1，0.9%氯化鈉溶液配制）組和黃芩苷脂質(zhì)體低、高劑量（50、100 mg·kg^-1）組，小鼠連續(xù)3 d霧化吸入黃芩苷脂質(zhì)體及黃芩苷溶液，每天1次，末次給藥1 h后除對照組外各組均鼻內(nèi)滴注脂多糖（LPS）構(gòu)建ARDS模型。造模6 h后，取肺臟檢測質(zhì)量濕干比（W/D），采用蘇木素-伊紅（HE）和Masson染色觀察肺組織病理變化，ELISA法觀察支氣管肺泡灌洗液（BALF）中白細(xì)胞介素-6（IL-6）、CC趨化因子配體2（CCL2）、腫瘤壞死因子-α（TNF-α）、轉(zhuǎn)化生長因子-β1（TGF-β1）水平以及肺組織中丙二醛（MDA）、超氧化物歧化酶（SOD）、谷胱甘肽（GSH）水平，實(shí)時熒光定量PCR（qRT-PCR）法檢測肺組織IL-6、TGF-β1、TNF-α和CCL2 mRNA表達(dá)，16S rRNA測序法觀察支氣管BALF菌群微生態(tài)的變化。將人正常肺上皮BEAS-2B細(xì)胞分為對照組、模型組、黃芩苷（200 μg·mL^-1）和黃芩苷脂質(zhì)體低、高質(zhì)量濃度（100、200 μg·mL^-1）組，除對照組外，均經(jīng)LPS（250 ng·mL^-1）刺激造模，造模的同時給藥，共培養(yǎng)72 h后，采用ELISA試劑盒檢測細(xì)胞中活性氧（ROS）、線粒體膜電位（MMP）和線粒體超氧化物水平。結(jié)果 黃芩苷脂質(zhì)體包封率為91.7%，載藥量為25.5%，粒徑為（212.300±0.424） nm，Zeta電位為（-22.4±0.9） mV，分散指數(shù)為0.517±0.052；體外釋放曲線顯示，黃芩苷脂質(zhì)體體外釋放速度顯著低于黃芩苷溶液（P＜0.05）。與模型組比較，黃芩苷脂質(zhì)體霧化吸入可緩解LPS造成的小鼠肺組織損傷，顯著降低肺W/D（P＜0.05），顯著降低BALF和肺組織中IL-6、TGF-β1、CCL2、TNF-α水平（P＜0.05），顯著升高肺組織GSH、SOD水平（P＜0.05），顯著降低肺組織MDA水平（P＜0.05），升高菌群厚壁菌門/擬桿菌門和菌群α多樣性（P＜0.05）。與模型組比較，黃芩苷脂質(zhì)體可顯著緩解由LPS誘導(dǎo)的BEAS-2B細(xì)胞活性氧（ROS）過度表達(dá)、線粒體超氧化物水平上調(diào)以及MMP下調(diào)（P＜0.05）。且黃芩苷脂質(zhì)體的上述改善作用均優(yōu)于黃芩苷溶液。結(jié)論 黃芩苷脂質(zhì)體霧化吸入對LPS誘導(dǎo)的肺損傷具有保護(hù)作用，機(jī)制與減輕細(xì)胞因子分泌過量引起的氧化損傷、線粒體功能障礙和肺部菌群失衡有關(guān)，脂質(zhì)體包裹可提高黃芩苷藥效。

Objective To investigate the protective effect of liposome aerosol inhalation of Baicalin on lung injury in mice with acute respiratory distress syndrome (ARDS) and explore its mechanism. Methods The liposomes of baicalein were prepared by the thin film hydration method, and the entrapment efficiency, drug loading, particle size, Zeta potential, polydispersity index and cumulative release rate were detected. BALB/c mice were randomly divided into the control group, the model group, the baicalein solution group (100 mg·kg^-1, prepared with 0.9% sodium chloride solution) and the low and high dose baicalein liposome groups (50, 100 mg·kg^-1). The mice were continuously nebulized with baicalein liposomes and baicalein solution for 3 days, once a day. One hour after the last administration, except for the control group, all groups were intranasally instilled with lipopolysaccharide (LPS) to establish the ARDS model. Six hours after modeling, the lungs were taken to detect the wet-to-dry weight ratio (W/D), and the pathological changes of lung tissue were observed by hematoxylin-eosin (HE) and Masson staining. The levels of interleukin-6 (IL-6), CC chemokine ligand 2 (CCL2), tumor necrosis factor-α (TNF-α), and transforming growth factor-β1 (TGF-β1) in bronchoalveolar lavage fluid (BALF) and the levels of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH) in lung tissue were detected by ELISA. The mRNA expressions of IL-6, TGF-β1, TNF-α and CCL2 in lung tissue were detected by real-time fluorescence quantitative PCR (qRT-PCR), and the changes of BALF microbiota microecology were observed by 16S rRNA sequencing. BEAS-2B cells were divided into the control group, the model group, the baicalein group (200 μg·mL^-1) and the low and high concentration baicalein liposome groups (100, 200 μg·mL^-1). Except for the control group, all groups were stimulated with LPS (250 ng·mL^-1) to establish the model, and the drugs were administered simultaneously. After co-culture for 72 h, the levels of reactive oxygen species (ROS), mitochondrial membrane potential (MMP) and mitochondrial superoxide in cells were detected by ELISA kits. Results The entrapment efficiency of baicalein liposomes was 91.7%, the drug loading was 25.5%, the particle size was (212.300 ±0.424) nm, the Zeta potential was (-22.4 ±0.9) mV, and the polydispersity index was 0.517 ±0.052. The in vitro release curve showed that the in vitro release rate of baicalein liposomes was significantly lower than that of baicalein solution (P < 0.05). Compared with the model group, nebulization of baicalein liposomes could alleviate the lung tissue injury caused by LPS in mice, significantly reduce the lung W/D (P < 0.05), significantly reduce the levels of IL-6, TGF-β1, CCL2 and TNF-α in BALF and lung tissue (P < 0.05), significantly increase the levels of GSH and SOD in lung tissue (P < 0.05), significantly reduce the level of MDA in lung tissue (P < 0.05), and increase the ratio of Firmicutes to Bacteroidetes and the α diversity of the microbiota (P < 0.05). Compared with the model group, baicalein liposomes could significantly alleviate the excessive expression of ROS, the up-regulation of mitochondrial superoxide and the down-regulation of MMP induced by LPS in BEAS-2B cells (P < 0.05). Moreover, the above-mentioned improvement effects of baicalein liposomes were better than those of baicalein solution. Conclusion Liposome aerosol inhalation of baicalin have a protective effect on LPSinduced lung injury, and the mechanism is related to the reduction of oxidative damage, mitochondrial dysfunction and lung microbiota imbalance caused by excessive cytokine secretion. Liposome encapsulation can improve the efficacy of baicalein.

R285.5

天津市中醫(yī)藥重點(diǎn)領(lǐng)域科研項(xiàng)目（2022008）;全國生物技術(shù)職業(yè)教育教學(xué)指導(dǎo)委員會教育教學(xué)改革項(xiàng)目（ XMLX202452）;天津市哲學(xué)社會科學(xué)規(guī)劃項(xiàng)目（TJJY23-004）