The MOE Key Laboratory of Standardization of Chinese Medicines, Shanghai Key Laboratory of Compound Chinese Medicines, and the SATCM Key Laboratory of New Resources and Quality Evaluation of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine (SHUTCM), Shanghai, 201203, China.
Anticancer Agents Med Chem. 2024;24(11):853-866. doi: 10.2174/0118715206286233240328045215.
Chronic inflammation is one of the causative factors for tumorigenesis. Gastrodin is a main active ingredient isolated from Gastrodia elata Blume, a famous medicinal herb with a long edible history.
This study aimed to explore the effects of gastrodin on colitis-associated carcinogenesis (CRC) in mice and to elucidate its potential molecular mechanisms.
Balb/c mice were induced with azoxymethane (AOM) and dextran sulfate sodium (DSS) for 12 weeks. Gastrodin (50 mg/kg) was administered via oral gavage three times per week until the end of the experiment. Disease indexes, including body weight, bloody diarrhea, colon length, histopathological score, and tumor size, were measured. Tumor cell proliferation was evaluated by BrdU incorporation assay and tumor cell cytotoxicity was assessed by cell counting kit (CCK-8). The expression levels of toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB) signaling molecules, NF-κB luciferase, and pro-inflammatory cytokines were determined by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR), immunoblotting, immunohistochemistry (IHC), enzyme-linked immunosorbent assay (ELISA), or reporter gene assays. The binding affinity between gastrodin and myeloid differentiation protein-2 (MD2) was analyzed by molecular docking and cellular thermal shift assay (CETSA).
Gastrodin administration was demonstrated to mitigate various CRC-related symptoms in mice, including weight loss, diarrhea, and tissue abnormalities. Notably, gastrodin suppressed tumor cell growth during colitis- associated tumorigenesis, resulting in fewer and smaller adenomas in the colon. Unlike irinotecan, a broadspectrum antitumor drug, gastrodin did not exhibit apparent cytotoxicity in various colorectal adenocarcinoma cell lines. Additionally, gastrodin downregulated TLR4/NF-κB signaling molecules and pro-inflammatory mediators in mice and macrophages. Molecular docking and CETSA experiments suggested that gastrodin binds to the MD2 protein, potentially interfering with the recognition of lipopolysaccharide (LPS) by TLR4, leading to NF-κB pathway inhibition.
This study provides evidence for the first time that gastrodin attenuated colitis and prevented colitisrelated carcinogenesis in mice, at least partially, by diminishing tumor-promoting cytokines through the interruption of TLR4/MD2/NF-κB signaling transduction.
慢性炎症是肿瘤发生的一个致病因素。天麻素是从著名药用植物天麻中分离得到的主要活性成分，已有长期食用历史。
本研究旨在探讨天麻素对结肠炎相关癌变（CRC）小鼠的作用，并阐明其潜在的分子机制。
Balb/c 小鼠用氧化偶氮甲烷（AOM）和葡聚糖硫酸钠（DSS）诱导 12 周。通过口服灌胃每周 3 次给予天麻素（50mg/kg），直至实验结束。测量疾病指标，包括体重、血性腹泻、结肠长度、组织学评分和肿瘤大小。通过 BrdU 掺入试验评估肿瘤细胞增殖，通过细胞计数试剂盒（CCK-8）评估肿瘤细胞细胞毒性。通过实时荧光定量聚合酶链反应（RT-qPCR）、免疫印迹、免疫组织化学（IHC）、酶联免疫吸附测定（ELISA）或报告基因分析测定 Toll 样受体 4（TLR4）/核因子 kappa-B（NF-κB）信号分子、NF-κB 荧光素酶和促炎细胞因子的表达水平。通过分子对接和细胞热转移分析（CETSA）分析天麻素与髓样分化蛋白-2（MD2）的结合亲和力。
天麻素给药可减轻结肠炎相关肿瘤发生过程中各种 CRC 相关症状，包括体重减轻、腹泻和组织异常。值得注意的是，天麻素抑制肿瘤细胞生长，导致结肠中腺瘤数量减少且体积更小。与广谱抗肿瘤药物伊立替康不同，天麻素在各种结直肠腺癌细胞系中均无明显细胞毒性。此外，天麻素下调小鼠和巨噬细胞中的 TLR4/NF-κB 信号分子和促炎介质。分子对接和 CETSA 实验表明，天麻素与 MD2 蛋白结合，可能通过干扰 TLR4 对脂多糖（LPS）的识别，从而抑制 NF-κB 通路。
本研究首次提供证据表明，天麻素通过中断 TLR4/MD2/NF-κB 信号转导，减少促肿瘤细胞因子，减轻结肠炎相关癌变小鼠的结肠炎和预防结肠炎相关癌变，至少部分发挥作用。
