[关键词]
[摘要]
目的 基于 16S rRNA 高通量测序探讨左金丸对胃热证大鼠肠道菌群的影响,揭示左金丸干预胃热证的 作用机制。方法 将 SD 大鼠随机分为正常组、模型组及左金丸组,每组 6 只。模型组及左金丸组大鼠灌胃辣 椒水煎液 (10 mL·kg-1 ) ,每日 2 次,连续 6 d。从第 4 天起,左金丸组灌胃左金丸水提液 (3.5 g·kg-1 ) ,每天 1 次, 连续 4 d,其他各组灌胃等体积蒸馏水。第 7 天,模型组与左金丸组灌胃无水乙醇 (1.5 mL) ,正常组给予等体 积蒸馏水灌胃。采用苏木精-伊红 (HE) 染色法观察胃组织病理变化;ELISA 法检测血清白细胞介素 2 (IL-2) 、 白细胞介素 8 (IL-8) 及胃组织前列腺素 E2 (PGE2 ) 、表皮生长因子 (EGF) 水平;16S rRNA 高通量测序分析肠道 菌群。结果 与正常组比较,模型组大鼠胃黏膜表面呈深红色,黏膜凹凸不平,毛细血管扩张、充血水肿及斑 块状或条索状出血;胃黏膜出现上皮细胞坏死脱落、腺体排列紊乱、大量炎性细胞浸润及红细胞外渗;血清IL-2、 IL-8 水平显著升高 (P<0.01) ,胃组织 PGE2、EGF 水平显著降低 (P<0.01) ;肠道菌群 Simpson 指数明显升高 (P<0.05) ,Shannon 指数明显降低 (P<0.05) ;肠道菌群结构与组成发生显著改变,拟杆菌门 (Bacteroidetes) 及 疣微菌门(Verrucomicrobia)相对丰度显著降低;11 个菌属相对丰度发生显著改变,其中 Prevotella_1、 Clostridium__innocuum_group、Streptococcus、Morganella 和 Klebsiella 的相对丰度均显著升高;Defluviitaleaceae_ UCG_011、Eubacterium__ventriosum_group、Lachnospiraceae_UCG_001、Mobilitalea、Eubacterium__xylanophilum_ group 和 Ruminococcus_1 的相对丰度均显著降低。与模型组比较,左金丸组大鼠胃黏膜仅见散在点状或线状 出血,肉眼损伤明显好转;胃黏膜仅见局灶性上皮脱落及少量炎性细胞浸润,病理损伤明显改善;血清 IL-2、 IL-8 水平显著降低 (P<0.01,P<0.05) ,胃组织 PGE2、EGF 水平显著升高 (P<0.01) ;肠道菌群 ACE、Chao1、 Shannon 指数均明显降低 (P<0.05) ;Defluviitaleaceae_UCG_011、Mobilitalea、Ruminococcus_1、Streptococcus、 Morganella和Klebsiell等6个关键菌属显著回调,且Proteus、Eubacterium__fissicatena_group、Erysipelatoclostridium、 Parasutterella、Prevotellaceae_NK3B31_group 和 Bacteroides 水平升高,Butyricimonas、Odoribacter 和 Tyzzerella 水平降低。结论 左金丸可能通过抑制炎症因子水平,调节肠道菌群紊乱,进而改善胃热证大鼠的病理损伤。
[Key word]
[Abstract]
Objective To investigate the effects of Zuojin Pills (ZJP) on gut microbiota in rats with gastric heat syndrome (GHS) using 16S rRNA high-throughput sequencing and elucidate its underlying mechanisms. Methods SD rats were randomly divided into three groups (n=6 per group) :normal control,GHS model,and ZJP treatment. The model and ZJP groups received intragastric administration of capsaicin decoction (10 mL·kg-1 ,twice daily) for 6 days. From day 4,the ZJP group was additionally given ZJP aqueous extract (3.5 g·kg-1 ,once daily) for 4 days,while other groups received equal volumes of distilled water. On day 7,after 24-hour fasting,the model and ZJP groups were administered anhydrous ethanol (1.5 mL),and the normal group received distilled water. Gastric histopathology was assessed via HE staining;serum interleukin-2 (IL-2),interleukin-8 (IL-8),and gastric tissue prostaglandin E2 (PGE2 ) and epidermal growth factor (EGF) levels were measured by ELISA;gut microbiota composition was analyzed via 16S rRNA sequencing. Results Compared with the normal group,the model group exhibited dark red gastric mucosa with uneven surfaces,capillary dilation,congestion,edema,and patchy/linear hemorrhages;histopathology revealed epithelial necrosis,glandular disarray,inflammatory infiltration,and erythrocyte extravasation. Serum IL-2 and IL-8 levels significantly increased (P<0.01),while gastric PGE2 and EGF levels decreased (P<0.01) . Gut microbiota analysis showed elevated Simpson index (P<0.05) and reduced Shannon index (P<0.05) ,with significant shifts in composition: decreased relative abundances of Bacteroidetes and Verrucomicrobia phyla, and altered abundances of 11 genera (e. g.,increased Prevotella_1,Clostridium_innocuum_group,Streptococcus,Morganella, Klebsiella; decreased Defluviitaleaceae_UCG_011, Eubacterium_ventriosum_group, Lachnospiraceae_UCG_001, Mobilitalea,Eubacterium_xylanophilum_group,Ruminococcus_1) . Comparison with the model group,rats in the ZJP group exhibited only scattered punctate or linear hemorrhages in gastric mucosa with significant macroscopic improvement. The ZJP group showed only focal gastric hemorrhages and mild inflammation,with significantly improved pathology. Serum IL-2 and IL-8 levels decreased (P<0.01,P<0.05) ,while gastric PGE2 and EGF levels increased (P<0.01) . Gut microbiota ACE,Chao1,and Shannon indices decreased (P<0.05),with reversal of 6 key genera (Defluviitaleaceae_UCG_011, Mobilitalea, Ruminococcus_1, Streptococcus, Morganella, Klebsiella) and enrichment of Proteus,Eubacterium_fissicatena_group,Erysipelatoclostridium,Parasutterella,Prevotellaceae_NK3B3 1_group, Bacteroides, alongside reduced Butyricimonas, Odoribacter, and Tyzzerella. Conclusion ZJP may ameliorate GHS by suppressing inflammatory cytokines and restoring gut microbiota homeostasis.
[中图分类号]
R285.5
[基金项目]
国家自然科学基金项目 (81403075) 。