实用医学杂志 ›› 2026, Vol. 42 ›› Issue (17): 3229-3238.doi: 10.3969/j.issn.1006-5725.2026.17.023

• 论著·机制与实践 • 上一篇    

胸腺法新调控LPS/TLR4信号通路改善坏死性小肠结肠炎小鼠的肠道炎症作用

周静1, 肖立鑫2, 杨瑞1, 周宇2, 王海龙2, 王朝阳2()   

  1. 1. 内蒙古医科大学基础医学院药理学教研室 (内蒙古 呼和浩特 010050 )
    2. 内蒙古医科大学附属医院胃肠外科 (内蒙古 呼和浩特 010000 )
  • 收稿日期:2026-01-29 出版日期:2026-09-10 发布日期:2026-10-10
  • 通讯作者: 王朝阳
  • 基金资助:
    内蒙古自治区自然科学基金(2023LHMS08004); 内蒙古医科大学联合项目(YKD2023LH053)

Thymic factor mediates improvement of intestinal injury in necrotizing enterocolitis by regulating the LPS/TLR4 signaling pathway

Jing Zhou1, Lixin Xiao2, Rui Yang1, Yu Zhou2, Hailong Wang2, Zhaoyang Wang2()   

  1. 1. Department of Pharmacology,School of Basic Medicine,Inner Mongolia Medical University,Hohhot 010050,Inner Mongolia,China
    2. Department of Gastroenterology,Inner Mongolia Medical University Affiliated Hospital,Hohhot 010000,Inner Mongolia,China
  • Received:2026-01-29 Online:2026-09-10 Published:2026-10-10
  • Contact: Zhaoyang Wang
  • About author:

    Zhou Jing performed the experiments, analyzed the data, and wrote the original draft of the article. Xiao Lixin and Yang Rui performed the experiments and assisted in data collection. Zhou Yu and Wang Hailong participated in the data analysis and revised the article. Wang Zhaoyang designed the study, supervised the research, and reviewed the final manuscript. All authors read and approved the final manuscript as submitted.

摘要:

目的 研究胸腺法新(thymosin alpha 1,Tα1)对坏死性小肠结肠炎(necrotizing enterocolitis,NEC)小鼠模型的抗炎作用及机制。 方法 30只5日龄SPF级C57BL/6J小鼠,随机分为5组:正常对照组(GC组)、NEC模型组(NEC组)、Tα1治疗组(TF组)、N-乙酰半胱氨酸治疗组(NAC组)、Tα1与N-乙酰半胱氨酸联合治疗组(TF+NAC组)。GC组由母乳喂养,NEC、TF、NAC和TF+NAC组采用配方奶人工喂养 + 缺氧 + LPS联合的方式建立新生小鼠NEC模型。治疗组(TF、NAC和TF+NAC组)建模第4天开始给予腹腔注射药物,给药5 d时对各组小鼠一同进行腹部X线拍摄后收集血液和肠道组织样本。HE染色观察肠道组织病理学改变;FITC-dextran 70KD(FD70)检测肠道通透性;ELISA法检测白细胞介素(IL)-6、IL-17A、肿瘤坏死因子(TNF)-α含量;流式细胞术检测Treg/Th17比率;Western blot检测toll样受体4(toll-like receptor 4, TLR4)、髓样分化因子88(myeloid differentiation factor 88, MyD88)、肿瘤坏死因子受体相关因子6(tumor necrosis factor receptor-associated factor 6, TRAF6)、β干扰素TIR结构域衔接蛋白(tir-domain-containing adapter-inducing interferon-β, TRIF)的蛋白表达水平。 结果 与GC组相比,NEC组小鼠出现生长发育迟缓、体质量下降、腹胀等情况;腹部X线检查可见严重肠道扩张,液平增多,部分区域可见肠壁积气;HE染色可见绒毛脱落、坏死,黏膜下层和固有层明显分离,伴炎细胞浸润,病理评分增加(P < 0.05);肠道通透性增高(P < 0.05);IL-6、IL-17A、TNF-α浓度增加(P < 0.05);Treg、Th17细胞水平上调,Treg/Th17比例降低(P < 0.05);TLR4、MyD88、TRAF6、TRIF的蛋白表达水平上调(P < 0.05)。与NEC组相比,治疗组小鼠体质量增加;腹部X线检查轻度肠道扩张,部分肠管可见散在气体影,未见明显液平或气腹;HE病理评分降低(P < 0.05);肠道通透性降低(P < 0.05);IL-6、IL-17A、TNF-α浓度降低(P < 0.05)且TF+NAC组下降更显著(P < 0.05);Treg、Th17细胞水平降低,Treg/Th17比例升高,且TF+NAC组Treg、Th17细胞水平降低、Treg/Th17比例升高更显著(P < 0.05);TLR4、MyD88、TRAF6、TRIF蛋白表达水平降低(P < 0.05)且TF+NAC组下降更显著(P < 0.05)。 结论 Tα1能改善NEC模型小鼠的肠道损伤,抑制炎症因子的表达,其作用机制可能是通过提高Treg/Th17比例及降低TLR4、MyD88、TRAF6和TRIF蛋白表达调控LPS/TLR4信号通路发挥作用。

关键词: 坏死性小肠结肠炎, 胸腺法新, Treg/Th17细胞平衡, TLR4信号通路, 免疫调节

Abstract:

Objective To investigate the anti-inflammatory efficacy and the underlying molecular mechanisms of Thymosin α1 (Tα1) in a mouse model of necrotizing enterocolitis (NEC). Methods Thirty 5-day-old specific pathogen-free (SPF) C57BL/6J mice were randomly divided into five groups: normal control group (GC), necrotizing enterocolitis (NEC) model group, Tα1 treatment group (TF), N-acetylcysteine (NAC) treatment group, and combined Tα1 and NAC treatment group (TF+NAC). The NEC model was established via formula feeding combined with hypoxia stimulation and lipopolysaccharide (LPS) challenge. Starting from the fourth day of modeling, mice in each treatment group received daily intraperitoneal injections for 5 consecutive days. Intestinal injury was assessed via abdominal X-ray examination, hematoxylin-eosin (HE) staining, and fluorescein isothiocyanate-dextran 70kDa (FD70) intestinal permeability assay. The levels of pro-inflammatory cytokines including interleukin-6 (IL-6), interleukin-17A (IL-17A) and tumor necrosis factor-α (TNF-α) were measured by enzyme-linked immunosorbent assay (ELISA). The ratio of regulatory T cells (Treg) to T helper 17 cells (Th17) was analyzed by flow cytometry, and the expression levels of TLR4/MyD88/TRAF6/TRIF signaling pathway proteins were detected by Western blot. Results Compared with the GC group, the NEC group exhibited significant growth retardation, intestinal distension, pneumatosis intestinalis, and mucosal barrier damage, accompanied by increased pro-inflammatory cytokine concentrations, an imbalanced Treg/Th17 ratio, and upregulated expression of TLR4 signaling proteins (P < 0.05). In contrast, the treatment groups showed attenuated intestinal injury, decreased pro-inflammatory cytokine concentrations, restored Treg/Th17 homeostasis, and downregulated expression of TLR4 signaling proteins (P < 0.05). Notably, the combined treatment of TF and NAC exerted superior efficacy in alleviating inflammatory storms and correcting immune dysregulation (P < 0.05). Conclusion Tα1 alleviates intestinal injury in NEC mouse models via inhibiting the TLR4 signaling pathway and correcting Treg/Th17 immune imbalance. Furthermore, the synergistic effect of Tα1 and cysteine offers a promising immunomodulatory strategy for the clinical management of NEC.

Key words: necrotizing enterocolitis, thymosin α1, Treg/Th17 balance, TLR4 signaling pathway, immunomodulation

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