Department of Geriatrics and Gastroenterology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China.
Autoimmunity. 2024 Dec;57(1):2427094. doi: 10.1080/08916934.2024.2427094. Epub 2024 Nov 13.
Pyroptosis plays an important role in maintenance of intestinal homeostasis, the abnormal activation of NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) inflammasome can promote the event and development of ulcerative colitis (UC). Its protective effects such as inhibiting pyroptosis in various inflammation-related diseases have been demonstrated, but whether resveratrol (RES) can also alleviate the progression of the disease by inhibiting pyroptosis in UC and the mechanism have rarely been studied. In this study, lipopolysaccharide (LPS) combined with adenosine triphosphate (ATP) was used to induce HT29 human colon cancer cells to construct an intestinal epithelial cell pyroptosis and inflammation model to investigate the anti-inflammatory effect of RES, reveal the regulatory mechanism of RES on pyroptosis, and provide a new theoretical basis for the treatment of UC. experiences, HT29 cells were dividing into control group, LPS/ATP group, RES low-dose group, RES high-dose group, NF-κB inhibitor pyrrolidine dithiocarbamate group (PDTC group), and LPS/ATP+PDTC group. The mRNA expressions of pyroptosis-related indicators such as NLRP3, apoptosis-associated speck-like protein containing CARD (ASC), Caspase-1(CASP1), IL-18, IL-1β, and inflammatory factors such as TNF-α and IL-6 were detected by qRT-PCR. The protein expressions of pyroptosis-related indicators NLRP3, ASC, CASP1, IL-18, IL-1β, NF-κB-p65 in the nucleus, and IκBα and p-IκBα in the cytoplasm were detected by Western blot. Immunofluorescence saw the distribution and expression of NLRP3, ASC and NF-κB-p65 protein in each group. The morphology and degree of pyroptosis in each group were observed by transmission electron microscope. The results showed that compared with the control group, the pyroptosis-related proteins including NLRP3, ASC, CASP1, IL-18, IL-1β, and inflammatory factors including TNF-α and IL-6 in the LPS/ATP group were increased, and LPS/ATP activated the activity of NF-κB signaling pathway. Compared with the LPS/ATP group, RES downregulated the expression of pyroptosis-related proteins and inflammatory factors in HT29 cells, and inhibited the activation of the NF-κB signaling pathway in HT29 cells pyroptosis. RES down-regulates the pyroptosis of HT29 cells induced by LPS/ATP and the expression of pyroptosis-related indicators NLRP3, ASC, CASP1, IL-18, IL-1β and inflammatory factors TNF-α and IL-6 in the inflammatory response and inhibits the occurrence of pyroptosis. The mechanism is related to the inhibition of NF-κB pathway activity.
细胞焦亡在维持肠道内稳态中发挥重要作用,NOD 样受体热蛋白结构域相关蛋白 3(NLRP3)炎症小体的异常激活可促进溃疡性结肠炎(UC)的发生和发展。已经证明其在各种炎症相关疾病中具有抑制细胞焦亡的保护作用,但白藜芦醇(RES)是否可以通过抑制 UC 中的细胞焦亡来减轻疾病的进展,以及其机制很少被研究。在这项研究中,使用脂多糖(LPS)联合三磷酸腺苷(ATP)诱导 HT29 人结肠癌细胞构建肠上皮细胞细胞焦亡和炎症模型,以研究 RES 的抗炎作用,揭示 RES 对细胞焦亡的调节机制,为 UC 的治疗提供新的理论依据。
经验,HT29 细胞分为对照组、LPS/ATP 组、RES 低剂量组、RES 高剂量组、NF-κB 抑制剂吡咯烷二硫代氨基甲酸盐(PDTC 组)和 LPS/ATP+PDTC 组。通过 qRT-PCR 检测细胞焦亡相关指标 NLRP3、凋亡相关斑点样蛋白含 CARD(ASC)、半胱天冬酶-1(CASP1)、IL-18、IL-1β 和 TNF-α 等炎症因子的 mRNA 表达。Western blot 检测细胞焦亡相关指标 NLRP3、ASC、CASP1、IL-18、IL-1β、核内 NF-κB-p65、胞质内 IκBα 和 p-IκBα 的蛋白表达。免疫荧光观察各组 NLRP3、ASC 和 NF-κB-p65 蛋白的分布和表达。透射电镜观察各组细胞焦亡的形态和程度。
结果显示,与对照组相比,LPS/ATP 组细胞焦亡相关蛋白 NLRP3、ASC、CASP1、IL-18、IL-1β 及炎症因子 TNF-α、IL-6 等均升高,LPS/ATP 激活 NF-κB 信号通路活性。与 LPS/ATP 组相比,RES 下调 HT29 细胞中细胞焦亡相关蛋白和炎症因子的表达,抑制 HT29 细胞中 NF-κB 信号通路的激活。RES 下调 LPS/ATP 诱导的 HT29 细胞焦亡及炎症反应中细胞焦亡相关指标 NLRP3、ASC、CASP1、IL-18、IL-1β 和炎症因子 TNF-α、IL-6 的表达,抑制细胞焦亡的发生。其机制与抑制 NF-κB 通路活性有关。