柚皮苷通过减轻氧化应激降低急性肺损伤小鼠内皮通透性的研究

Effect of naringin on endothelial permeability in mice with acute lung injury by alleviating oxidative stress

目的研究柚皮苷对脂多糖(LPS)诱导的小鼠急性肺损伤模型肺微血管内皮通透性及气道炎症的改善作用。方法将66只C57BL/6雄性小鼠随机分为对照组、模型组、地塞米松组及柚皮苷40、80、120 mg/kg组,每组11只。对照组小鼠正常饲养;模型组和给药组小鼠麻醉后给予LPS滴鼻,每只小鼠滴鼻50μL。柚皮苷40、80、120 mg/kg组和地塞米松5mg/kg组在LPS滴鼻前分别ig相应剂量的柚皮苷和地塞米松,连续给药5 d,滴鼻后继续ig相应剂量的柚皮苷和地塞米松,连续给药2 d。对照组和模型组同时间ig 0.2 m L生理盐水。苏木精–伊红(HE)染色观察肺实质病理变化;血常规分析仪检测血液及肺泡灌洗液淋巴细胞、中性粒细胞、血细胞、血小板数量;ELISA检测肺泡灌洗液白细胞介素(IL)-1β、IL-6、肿瘤坏死因子-α(TNF-α)含量和血清内皮素-1(ET-1)水平;肺组织伊文思蓝成像分析肺泡–血管通透性,q PCR检测紧密连接蛋白紧密连接蛋白-1(ZO-1)、密封蛋白(OCLN)、血管内皮钙黏素(VE-cadherin)、β-连环蛋白(β-catenin)和水通道蛋白AQP1、AQP5的m RNA表达水平;化学分析法检测血清丙二醛(MDA)、超氧化物歧化酶(SOD)、一氧化氮(NO)水平。结果与模型组相比,柚皮苷120 mg/kg组能够显著改善LPS诱导的急性肺损伤小鼠肺水肿及肺组织炎症浸润的病理状态,减少肺泡内炎症细胞数量、炎症因子和总蛋白含量,以及肺组织伊文思蓝渗入量;增强紧密连接蛋白和水通道蛋白表达;减缓血液炎症细胞流失,降低血管氧化应激水平(P<0.05)。结论柚皮苷能够减轻LPS诱导的气道炎症,并可能通过降低血管氧化应激水平减少对紧密链接蛋白和水通道蛋白的损害作用从而改善肺内皮高通透性。

Objective To study the effect of naringin on pulmonary microvascular endothelial permeability and airway inflammation in mice model of acute lung injury induced by lipopolysaccharide(LPS).Methods Sixty-six male C57BL/6 mice were randomly divided into control group,model group,dexamethasone group,and naringin 40,80,120 mg/kg groups,with 11 mice in each group.Control group mice were fed normally.Mice in the model group and the administration group were given LPS nasal drops after anesthesia,each mice was given 50μL nasal drops.Naringin 40,80,and 120 mg/kg groups and dexamethasone 5 mg/kg groups were intragastrically given naringin and dexamethasone at corresponding doses before LPS nasal drops for 5 days,respectively,and intragastrically given naringin and dexamethasone at corresponding doses after nasal drops for 2 days.Control group and model group were given 0.2 mL normal saline at the same time.Hematoxylin-eosin(HE)staining was used to observe the pathological changes of lung parenchyma.The number of lymphocytes,neutrophils,blood cells and platelets in blood and alveolar lavage fluid were detected by blood routine analyzer.The contents of interleukin-1β,IL-6,tumor necrosis factor-α(TNF-α)and serum endothelin-1(ET-1)in alveolar lavage fluid were determined by ELISA.Evens blue imaging of lung tissue to analyze alveolar-vascular permeability,qPCR was used to detect the mRNA expression levels of tight junction protein-1(ZO-1),sealing protein(OCLN),vascular endothel ial cadherin(VE-cadherin),β-catenin(β-catenin)and aquaporins AQP1 and AQP5.Serum levels of malondialdehyde(MDA),superoxide dismutase(SOD)and nitric oxide(NO)were detected by chemical analysis.Results Compared with model group,naringin 120 mg/kg group could significantly improve the pathological state of pulmonary edema and inflammatory infiltration of lung tissue in mice with LPS-induced acute lung injury,reduce the number of inflammatory cells in alveolar,the contents of inflammatory factors and total protein,and the infiltration amount of Evans blue in lung tissue.Enhance the expression of tight junction protein and aquaporin;decrease the loss of blood inflammatory cells and decrease the level of vascular oxidative stress(P<0.05).Conclusion Naringin can reduce LPS-induced airway inflammation,and may improve pulmonary endothelial hyperpermeability by reducing vascular oxidative stress levels and reducing damaging effects on tightlink protein and aquaporin.