基于黏液和黏膜屏障探究楹树皂苷对乙醇致大鼠急性胃溃疡的保护作用机制  

Protective effect of Albizia chinensis saponin on ethanol-induced gastric mucosal injury in rats focus on mucus and mucosal barriers

作　　者：贾晓雨 张建军[1] JIA Xiao-yu;ZHANG Jian-jun(State Key Laboratory of Digestive Health,Institute of Materia Medica,Chinese Academy of Medical Sciences&Peking Union Medical College,Beijing 100050,China)

机构地区：[1]中国医学科学院,北京协和医学院,药物研究所,消化健康全国重点实验室,北京100050

出　　处：《中国中药杂志》2024年第12期3340-3347,共8页China Journal of Chinese Materia Medica

基　　金：国家自然科学基金重大项目(82293680);协和医学实验室建设专项(2023-I2M-2-009)。

摘　　要：探究楹树皂苷对乙醇致大鼠急性胃溃疡的保护作用及其机制。SD大鼠实验前24 h禁食不禁水,正常对照组和模型组灌胃水,阳性药组灌胃雷贝拉唑钠溶液(40 mg·kg^(-1)),受试物组灌胃不同剂量的楹树皂苷溶液(3、10、30 mg·kg^(-1)),30 min后正常对照组灌胃1.5 mL水,其余各组均灌胃等体积95%乙醇造模,6 h后颈椎脱臼法处死大鼠取胃。统计出血面积,计算溃疡指数;苏木素-伊红(HE)染色检测胃组织病理改变;高碘酸-席夫(PAS)染色检测胃黏膜表面黏液分布;酶联免疫吸附法(ELISA)检测胃黏膜磷脂和氨基己糖含量;Western blot检测胃组织碳酸氢根转运体、基质金属蛋白酶和细胞间紧密连接相关蛋白表达量;免疫组织化学(immunohistochemistry, IHC)染色检测分泌型黏蛋白和紧密连接相关蛋白阳性细胞。结果显示正常对照组大鼠胃组织表面光滑无出血点,模型组大鼠胃溃疡指数为35±11,楹树皂苷在3、10、30 mg·kg^(-1)剂量下对大鼠胃溃疡的抑制率分别为46%(P<0.01)、85%(P<0.001)、100%(P<0.001)。模型组大鼠胃黏膜结构破坏严重,无法观察到黏液层。与模型组相比,楹树皂苷组大鼠胃黏膜表面黏液层完整,黏液中磷脂和氨基己糖含量显著增加,分泌型黏蛋白MUC5AC阳性细胞数明显增多,碳酸氢根转运体SLC26A3和CFTR的表达水平显著提高,应激活化蛋白激酶c-Jun氨基末端激酶(JNK)和核转录因子c-Jun磷酸化显著减少,基质金属蛋白酶(MMP)-8表达量明显降低,同时检测到MMP-8内源性抑制剂(TIMP-1)表达升高,紧密连接蛋白Occludin和ZO-1表达量明显增加。结果表明楹树皂苷一方面通过上调分泌型黏蛋白MUC5AC以及磷脂和氨基己糖含量,同时提高碳酸氢根转运体SLC26A3和CFTR的表达水平来增强黏液-碳酸氢盐屏障功能;另一方面通过抑制JNK信号通路,阻止MMP-8过度活化,从而减少Occludin和ZO-1的降解来增强黏膜屏障功能。即楹树皂苷在黏液屏障�This study aims to explore the protective effect of Albizia chinensis saponin on ethanol-induced acute gastric ulcer in rats and elucidate its mechanisms.SD rats were deprived of water for 24 hours before the experiment.The control group and model group were administered water by gavage,and the positive drug group received rabeprazole sodium solution(40 mg·kg^(-1))by gavage.The experimental groups were given different doses of Albizia chinensis saponin solution(3,10,and 30 mg·kg^(-1)).After 30 minutes,the control group received 1.5 mL of water by gavage,while the other groups were administered an equal volume of 95%ethanol for modeling.After six hours,the rats were killed by cervical dislocation,and the stomachs were collected.The ulcer area was measured,and the ulcer index was calculated.Hematoxylin-eosin(HE)staining was performed to assess histopathological changes in gastric tissue.Periodic acid-Schiff(PAS)staining was used to evaluate the distribution of gastric mucosal surface mucus.Enzyme-linked immunosorbent assay(ELISA)was employed to measure the levels of phospholipids and aminohexose in the gastric mucosa.Western blot was performed to determine the expression levels of the bicarbonate transporter,matrix metalloproteinase,and tight junctionassociated proteins in gastric tissue.Immunohistochemistry(IHC)staining was conducted to quantify the number of positive cells for secreted mucin and tight junction-associated proteins.The results showed that the gastric tissue surface of rats in the control group was smooth without ulceration,and the gastric ulcer index of rats in the model group was 35±11.Albizia chinensis saponin at doses of 3,10,and 30 mg·kg^(-1) resulted in inhibition rates of gastric ulcer of 46%(P<0.01),85%(P<0.001),and 100%(P<0.001),respectively.Severe disruption of gastric mucosal structure and absence of the mucus layer were observed in the model group.Compared with the model group,the Albizia chinensis saponin group showed intact gastric mucosal surface mucus layer,significantly increase

关 键 词：楹树皂苷 胃溃疡 黏液-碳酸氢盐屏障 黏膜屏障 细胞间紧密连接 基质金属蛋白酶 

分 类 号：R285.5[医药卫生—中药学]