Department of Gastroenterology, the Second Affiliated Hospital of Jiaxing University, Jiaxing, China.
J Biochem Mol Toxicol. 2022 Nov;36(11):e23188. doi: 10.1002/jbt.23188. Epub 2022 Aug 4.
This study focuses on exploring the role and mechanism of moronic acid (MOA), a small triterpenoid molecule, against inflammatory bowel disease (IBD). Intestinal macrophages were cultured in vitro, and their M1 polarization was induced by lipopolysaccharide (LPS) and interferon gamma (IFN-γ). After intervention with MOA, the proportion of M1 macrophages was detected, and the levels of inflammatory cytokines (TNF-α, IL-6, and IL-1β) were examined by ELISA. IFA staining was performed to determine the P50 and CD86 expressions, while DCFH-DA was used to determine the reactive oxygen species (ROS) level, as well as the p-P50 and NLRP3 protein levels. Additionally, we also used N-acetylcysteine, a ROS inhibitor, to further explore the association between MOA and ROS-NF-κB signaling. In murine experimentation, colitis was induced in mice with DSS. After MOA intervention, we assessed the mucosal barrier damage, tissue ROS, as well as protein and inflammatory cytokine levels. MOA could inhibit the M1 polarization of intestinal macrophages, suppress the expressions of inflammatory cytokines, and reduce the level of ROS-NF-κB-NLRP3 signaling. After inhibiting ROS through NAC treatment, the effect of MOA was evidently weakened. Clearly, MOA exerted its activity via ROS. In the murine model, MOA could lower the CD86 level in the intestinal tissues, inhibit the M1 polarization of macrophages, and reduce the tissue levels of inflammatory cytokines. This study finds that MOA can regulate ROS-NF-κB-NLRP3 signaling by inhibiting ROS, thereby suppressing the M1 polarization of intestinal macrophages, which plays a protective role in IBD.
本研究旨在探讨熊果酸（MOA）作为一种小分子三萜类化合物在炎症性肠病（IBD）中的作用及机制。体外培养肠巨噬细胞，用脂多糖（LPS）和干扰素γ（IFN-γ）诱导其 M1 极化。用 MOA 干预后，检测 M1 巨噬细胞的比例，ELISA 检测炎症细胞因子（TNF-α、IL-6、IL-1β）水平。IFA 染色检测 P50 和 CD86 表达，DCFH-DA 检测活性氧（ROS）水平及 p-P50 和 NLRP3 蛋白水平。同时，用 ROS 抑制剂 N-乙酰半胱氨酸（NAC）进一步探讨 MOA 与 ROS-NF-κB 信号通路的关系。在小鼠实验中，用 DSS 诱导小鼠结肠炎。用 MOA 干预后，评估黏膜屏障损伤、组织 ROS 以及蛋白和炎症细胞因子水平。MOA 能抑制肠道巨噬细胞 M1 极化，抑制炎症细胞因子表达，降低 ROS-NF-κB-NLRP3 信号通路水平。用 NAC 抑制 ROS 后，MOA 的作用明显减弱。显然，MOA 通过 ROS 发挥作用。在小鼠模型中，MOA 能降低肠道组织中 CD86 水平，抑制巨噬细胞 M1 极化，降低组织炎症细胞因子水平。本研究发现 MOA 能通过抑制 ROS 调节 ROS-NF-κB-NLRP3 信号通路，从而抑制肠道巨噬细胞 M1 极化，在 IBD 中发挥保护作用。
