Department of Food Science, Gyeongsang National University, Jinju, 52725, Republic of Korea.
Department of Plant Science and Technology, Chung-Ang University, Anseong, 17546, Republic of Korea.
J Ethnopharmacol. 2024 Jan 30;319(Pt 1):117105. doi: 10.1016/j.jep.2023.117105. Epub 2023 Sep 3.
Taraxacum coreanum Nakai (TC) is a dandelion native to Korea that has long been used as a medicinal herb with antioxidant and anti-inflammatory properties. Intestinal inflammation is closely associated with intestinal epithelial barrier disruption, which leads to the progression of various intestinal diseases.
The aim of this study was to investigate the protective effects of TC extract on inflammatory responses and intestinal barrier dysfunction in lipopolysaccharide (LPS)-stimulated Caco-2 cells.
The inhibitory effect of TC on nitric oxide (NO) and pro-inflammatory cytokines production were determined by Griess reagent and enzyme-linked immunosorbent assay, respectively. The epithelial permeability was evaluated by transepithelial electrical resistance (TEER) assay, and inflammation- and tight junction (TJ)-related protein expression were analyzed by Western blotting. In addition, the presence of ten active compounds was identified and quantified using UHPLC-ESI-MS and HPLC-DAD analyses.
Treatment with TC significantly reduced NO production and pro-inflammatory cytokines production [interleukin (IL)-6 and tumor necrosis factor (TNF)-α] compared to the group treated with LPS only, particularly at 100 μg/mL. TC significantly decreased monolayer permeability as detected by TEER. In addition, the transmission of fluorescein isothiocyanate-dextran 4 across the barrier was decreased after treatment with TC. Inflammation-related proteins (inducible NO synthase, cyclooxygenase-2, TNF-α, IL-6, and IL-1β) were down-regulated after treatment with TC. In contrast, TC significantly increased the protein levels of the TJ-related protein, claudin-5. Ten phytochemicals (protocatechuic acid, chlorogenic acid, caffeic acid, scopoletin, chicoric acid, hyperoside, nicotiflorin, luteoloside, sophoricoside, and luteolin) were identified by UHPLC-ESI-MS and HPLC-DAD analysis.
Our findings suggest that ethanolic extract of TC could attenuate the LPS-induced intestinal barrier dysfunction by increasing the TJ protein and suppressing inflammatory responses.
朝鲜蒲公英（TC）是一种原产于朝鲜的蒲公英，长期以来一直被用作具有抗氧化和抗炎特性的草药。肠道炎症与肠道上皮屏障破坏密切相关，这导致各种肠道疾病的进展。
本研究旨在探讨 TC 提取物对脂多糖（LPS）刺激的 Caco-2 细胞炎症反应和肠道屏障功能障碍的保护作用。
通过格里斯试剂和酶联免疫吸附试验分别测定 TC 对一氧化氮（NO）和促炎细胞因子产生的抑制作用。通过跨上皮电阻（TEER）测定评估上皮通透性，并通过 Western blot 分析炎症和紧密连接（TJ）相关蛋白的表达。此外，使用 UHPLC-ESI-MS 和 HPLC-DAD 分析鉴定和定量十种活性化合物。
与单独用 LPS 处理的组相比，TC 处理可显著降低 NO 产生和促炎细胞因子（IL-6 和 TNF-α）的产生，尤其是在 100μg/mL 时。TC 可显著降低 TEER 检测到的单层通透性。此外，在用 TC 处理后，荧光素异硫氰酸酯-葡聚糖 4 的传递穿过屏障减少。在用 TC 处理后，炎症相关蛋白（诱导型一氧化氮合酶、环加氧酶-2、TNF-α、IL-6 和 IL-1β）的表达下调。相反，TC 显著增加了 TJ 相关蛋白 Claudin-5 的蛋白水平。通过 UHPLC-ESI-MS 和 HPLC-DAD 分析鉴定了十种植物化学物质（原儿茶酸、绿原酸、咖啡酸、山柰酚、菊苣酸、异槲皮苷、芦丁、槐糖苷、槐糖苷和木犀草素）。
我们的研究结果表明，TC 的乙醇提取物可通过增加 TJ 蛋白和抑制炎症反应来减轻 LPS 诱导的肠道屏障功能障碍。
