小建中颗粒通过调节肠道菌群修复肠道屏障抑制食物过敏

Xiaojianzhong Granule inhibits food allergy by regulating gut microbiota and repairing intestinal barrier

摘要

目的 研究小建中颗粒对食物过敏（food allergy，FA）的抑制作用，并分析肠道菌群和闭锁连接蛋白-1（zonula occluden-1，ZO-1）、闭锁蛋白（Occludin）探讨相关机制。 方法 24只SPF级雌性BALB/c小鼠随机分为正常组、模型组、预防组、治疗组，每组6只。首次激发前3 d，预防组以标准剂量［5.85 g/（kg·d）］小建中颗粒灌胃，至末次激发前4 h；治疗组过敏评分后给予2倍剂量小建中颗粒3 d；其他组给予等体积蒸馏水灌胃。实验终点，行过敏评分、测肛温；流式检测肠系膜淋巴结（mesenteric lymph nodes，MLN）嗜酸性粒细胞和肥大细胞，甲苯胺蓝染色空肠组织肥大细胞，免疫组织化学法检测ZO-1、Occludin的表达；16S rRNA测序检测肠内容物菌群，高效液相色谱-质谱法分析空肠灌洗液短链脂肪酸（short-chain fatty acids，SCFAs）含量。 结果 与模型组相比，预防组和治疗组过敏评分（P=0.000，P=0.000）和肛温差下降（P=0.002，P=0.000），MLN嗜酸性粒细胞和肥大细胞比例减少（P=0.000，P=0.002；P=0.000，P=0.000），空肠肥大细胞浸润减少（P=0.000，P=0.000）。与正常组相比，模型组厚壁菌门丹毒丝菌科和苏黎世杆菌属相对丰度增加，而预防组和治疗组丹毒丝菌科和苏黎世杆菌属消失，紫单胞菌科相对丰度增加。与正常组相比，模型组空肠灌洗液丙酸盐含量减少（P=0.014），与模型组相比，预防组空肠灌洗液丙酸盐含量增加（P=0.024），治疗组明显增加（P=0.008）。模型组ZO-1表达下调（P=0.010），Occludin表达明显下调（P=0.002），而预防组和治疗组ZO-1、Occludin表达恢复正常（P=0.001，P=0.013；P=0.025，P=0.015）。 结论 小建中颗粒可改变肠道菌群组成和丰度，增加短链脂肪酸浓度，上调ZO-1、Occludin的表达，促进肠道屏障修复，抑制FA。

Abstract

Objective To investigate the inhibitory effect of Xiaojianzhong Granule（XJZG） on food allergy（FA） and related mechanisms in terms of gut microbiota，zonula occluden-1（ZO-1），and Occludin. Methods A total of 24 specific pathogen-free female BALB/c mice were randomly divided into normal group，model group，prevention group，and treatment group，with 6 mice in each group. The mice in the prevention group were given XJZG by gavage at a standard dose of 5.85 g/kg/day from 3 days before the first challenge till 4 hours before the last challenge；the mice in the treatment group were given XJZG at the double dose for 3 days based on the allergy score； the mice in the other groups were given an equal volume of distilled water by gavage. At the end of the experiment，allergy score and anal temperature were measured； flow cytometry was used to measure eosinophils and mast cells in mesenteric lymph nodes（MLNs）；toluidine blue staining was performed for mast cells in jejunal tissue； immunohistochemistry was used to measure the expression of ZO-1 and Occludin；16S rRNA sequencing was performed to analyze the microbiota in the intestinal content；high-performance liquid chromatography-mass spectrometry was used to measure the content of short-chain fatty acids（SCFAs） in jejunal lavage fluid. Results Compared with the model group，the prevention group and the treatment group had significant reductions in allergy score（P=0.000，P=0.000），anal temperature（P=0.002，P=0.000），the proportion of eosinophils and mast cells in MLNs（P<0.05），and mast cell infiltration in jejunal tissue（P=0.000，P=0.000）. Compared with the normal group，the model group had significant increases in the relative abundances of Erysipelaceae and Turicibacter，while the prevention group and the treatment group had disappearance of Erysipelaceae and Turicibacter and an increase in the relative abundance of Porphyromonadaceae. Compared with the normal group，the model group had a significant reduction in the content of propionate in jejunal lavage fluid（P=0.014），and compared with the model group，the prevention group had a significant increase in the content of propionate in jejunal lavage fluid（P=0.024），as well as a significant increase in the treatment group（P=0.008）. In the model group，the expression of ZO-1 was downregulated（P=0.010），and the expression of Occludin was significantly downregulated（P=0.002），while the expression of ZO-1 and Occludin returned to normal levels in the prevention group and the treatment group（P=0.001，P=0.013；P=0.025，P=0.015）. Conclusion XJZG can change the composition and abundance of gut microbiota，increase the concentration of SCFAs，upregulate the expression of ZO-1 and Occludin，promote the repair of intestinal barrier，and inhibit food allergy.

关键词

小建中颗粒 / 食物过敏 / 肠道菌群 / 短链脂肪酸 / 闭锁连接蛋白-1

Key words

Xiaojianzhong Granule / food allergy / gut microbiota / short-chain fatty acids / zonula occluden-1

基金资助

国家自然科学基金资助项目(81701590)

山东省高等学校“青创科技支持计划”资助项目(2021KJ106)

大学生创新创业训练计划资助项目(X2022023)