University of Wisconsin-Madison, Department of Food Science, 1605 Linden Dr., Madison, WI, 53711, USA.
University of Wisconsin-Madison, Department of Food Science, 1605 Linden Dr., Madison, WI, 53711, USA.
Arch Biochem Biophys. 2020 Jul 30;688:108409. doi: 10.1016/j.abb.2020.108409. Epub 2020 May 25.
The objective of this work was to determine how aronia berry polyphenols and its microbial catabolites improve intestinal barrier function. Caco-2 cells were cultured on transwell plates and allowed differentiate to form a model intestinal barrier, having baseline transepithelial electrical resistance (TEER) ≥ 300 Ω cm. Barrier function of differentiated Caco-2 cells was compromised by the addition of an inflammatory cocktail (IC: TNF-α, IL-1β, and IFN-γ to the basolateral media and lipopolysaccharide to the apical media). Polyphenol-rich aronia berry powder or individual polyphenols representative of parent compounds or catabolites were applied to the basolateral media concurrently with IC. TEER was determined subsequently by chopstick electrode or continuous analysis. Permeability was determined by application of 4 kDa FITC-dextran or Lucifer yellow. Expression of tight junction proteins was assessed by qRT-PCR analysis. Application of the IC to differentiated Caco-2 cells routinely reduced TEER by ~40% within 24 h. Individual polyphenols representative of parent compounds or phenolic microbial catabolites at 100 μM did not inhibit IC reduction of TEER in Caco-2 cells. Whole aronia berry powder inhibited loss of TEER by ~50% at 24 h after application of the IC. Furthermore 5 mg/mL of aronia berry powder prevented an IC-induced barrier permeability of FITC-dextran and Lucifer yellow. After 12 h of IC treatment, Caco-2 cells had increased claudin 1 (CLDN1) relative to the untreated control. Application of aronia berry powder inhibited CLDN1 and also increased expression of zonula ocludens-1 (ZO-1) after 12 h. In summary, aronia berry, but not its microbiota-derived catabolites improved intestinal barrier function in a cellular model of chronic colonic inflammation. In this case, improved barrier function was associated with modulation of tight junction expression.
本研究旨在探讨黑果腺肋花楸多酚及其微生物代谢产物如何改善肠道屏障功能。将 Caco-2 细胞培养在 Transwell 板上，并允许其分化形成肠道屏障模型，基础跨上皮电阻（TEER）≥300Ω·cm。通过向基底外侧培养基中添加炎症鸡尾酒（IC：TNF-α、IL-1β 和 IFN-γ，以及向顶端培养基中添加脂多糖）来破坏分化的 Caco-2 细胞的屏障功能。多酚丰富的黑果腺肋花楸粉末或代表母体化合物或代谢物的单一多酚同时应用于基底外侧培养基中，并与 IC 一起应用。随后通过筷子电极或连续分析测定 TEER。通过应用 4 kDa FITC-右旋糖酐或 Lucifer yellow 测定通透性。通过 qRT-PCR 分析评估紧密连接蛋白的表达。将 IC 应用于分化的 Caco-2 细胞通常会在 24 小时内将 TEER 降低约 40%。代表母体化合物或酚类微生物代谢物的单一多酚在 100 μM 时不会抑制 Caco-2 细胞中 IC 降低 TEER。整个黑果腺肋花楸粉末在应用 IC 后 24 小时内抑制 TEER 的损失约 50%。此外，5mg/mL 的黑果腺肋花楸粉末可防止 IC 诱导的 FITC-右旋糖酐和 Lucifer yellow 的屏障通透性。在 IC 处理 12 小时后，Caco-2 细胞中 Claudin 1（CLDN1）的表达相对于未处理对照增加。黑果腺肋花楸粉末的应用抑制了 CLDN1 的表达，并在 12 小时后也增加了 zonula ocludens-1（ZO-1）的表达。总之，黑果腺肋花楸，而不是其微生物衍生的代谢产物，改善了慢性结肠炎症细胞模型中的肠道屏障功能。在这种情况下，改善的屏障功能与紧密连接表达的调节有关。
