背景:溃疡性结肠炎(UC)是由病因不确定的胃肠道内持续的炎症过程定义的。目前的治疗方法在解决氧化应激的能力方面受到限制,炎症,屏障功能恢复,以协调的方式调节肠道菌群,以维持肠道稳态。
结果:该研究涉及通过铁离子介导的姜黄素氧化偶联来构建金属-酚类纳米酶(Cur-Fe)。Cur-Fe纳米酶表现出超氧化物歧化酶(SOD)样和•OH清除活性,证明了在体外维持细胞内氧化还原平衡的显着抗炎和抗氧化特性。从大肠杆菌Nissle1917(EcN)中汲取灵感,随后通过将Cur-Fe整合到EcN膜(EM)中来开发仿生Cur-Fe纳米酶(CF@EM),以提高Cur-Fe纳米酶的体内靶向能力和治疗效果。口服时,CF@EM在DSS诱导的结肠炎模型中显示出强的定植发炎的结肠和恢复肠氧化还原平衡和屏障功能的能力。重要的是,CF@EM通过增强细菌多样性和将组成结构转变为抗炎表型来影响肠道微生物组朝向有益状态。此外,肠道微生物代谢产物的分析支持CF@EM的疗效与胆汁酸代谢密切相关的观点。
结论:受肠道微生物的启发,我们已经成功地合成了一种具有抑制炎症和恢复肠道稳态能力的仿生Cur-Fe纳米酶。总的来说,没有明显的全身毒性,这项工作为靶向口服纳米药物治疗溃疡性结肠炎提供了前所未有的机会.
BACKGROUND: Ulcerative colitis (UC) is defined by persistent inflammatory processes within the gastrointestinal tract of uncertain etiology. Current therapeutic approaches are limited in their ability to address oxidative stress, inflammation, barrier function restoration, and modulation of gut microbiota in a coordinated manner to maintain intestinal homeostasis.
RESULTS: This study involves the construction of a metal-phenolic nanozyme (Cur-Fe) through a ferric ion-mediated oxidative coupling of curcumin. Cur-Fe nanozyme exhibits superoxide dismutase (SOD)-like and •OH scavenging activities, demonstrating significant anti-inflammatory and anti-oxidant properties for maintaining intracellular redox balance in vitro. Drawing inspiration from Escherichia coli Nissle 1917 (EcN), a biomimetic Cur-Fe nanozyme (CF@EM) is subsequently developed by integrating Cur-Fe into the EcN membrane (EM) to improve the in vivo targeting ability and therapeutic effectiveness of the Cur-Fe nanozyme. When orally administered, CF@EM demonstrates a strong ability to colonize the inflamed colon and restore intestinal redox balance and barrier function in DSS-induced colitis models. Importantly, CF@EM influences the gut microbiome towards a beneficial state by enhancing bacterial diversity and shifting the compositional structure toward an anti-inflammatory phenotype. Furthermore, analysis of intestinal microbial metabolites supports the notion that the therapeutic efficacy of CF@EM is closely associated with bile acid metabolism.
CONCLUSIONS: Inspired by gut microbes, we have successfully synthesized a biomimetic Cur-Fe nanozyme with the ability to inhibit inflammation and restore intestinal homeostasis. Collectively, without appreciable systemic toxicity, this work provides an unprecedented opportunity for targeted oral nanomedicine in the treatment of ulcerative colitis.