Department of Medicinal Chemistry & Pharmacognosy, University of Illinois College of Pharmacy, 833 South Wood Street, Chicago, Illinois 60612, United States.
Chem Res Toxicol. 2012 Dec 17;25(12):2725-36. doi: 10.1021/tx3003609. Epub 2012 Oct 18.
The promising therapeutic potential of the NO-donating hybrid aspirin prodrugs (NO-ASA) includes induction of chemopreventive mechanisms and has been reported in almost 100 publications. One example, NCX-4040 (pNO-ASA), is bioactivated by esterase to a quinone methide (QM) electrophile. In cell cultures, pNO-ASA and QM-donating X-ASA prodrugs that cannot release NO rapidly depleted intracellular GSH and caused DNA damage; however, induction of Nrf2 signaling elicited cellular defense mechanisms including upregulation of NAD(P)H:quinone oxidoreductase-1 (NQO1) and glutamate-cysteine ligase (GCL). In HepG2 cells, the "NO-specific" 4,5-diaminofluorescein reporter, DAF-DA, responded to NO-ASA and X-ASA, with QM-induced oxidative stress masquerading as NO. LC-MS/MS analysis demonstrated efficient alkylation of Cys residues of proteins including glutathione-S-transferase-P1 (GST-P1) and Kelch-like ECH-associated protein 1 (Keap1). Evidence was obtained for alkylation of Keap1 Cys residues associated with Nrf2 translocation to the nucleus, nuclear translocation of Nrf2, activation of antioxidant response element (ARE), and upregulation of cytoprotective target genes. At least in cell culture, pNO-ASA acts as a QM donor, bioactivated by cellular esterase activity to release salicylates, NO(3)(-), and an electrophilic QM. Finally, two novel aspirin prodrugs were synthesized, both potent activators of ARE, designed to release only the QM and salicylates on bioactivation. Current interest in electrophilic drugs acting via Nrf2 signaling suggests that QM-donating hybrid drugs can be designed as informative chemical probes in drug discovery.
NO 供体型阿司匹林前药（NO-ASA）具有有前景的治疗潜力，包括诱导化学预防机制，这在近 100 篇出版物中已有报道。一个例子是 NCX-4040（pNO-ASA），它被酯酶生物转化为醌甲（QM）亲电试剂。在细胞培养物中，pNO-ASA 和不能快速释放 NO 的 QM 供体 X-ASA 前药迅速耗尽细胞内 GSH 并导致 DNA 损伤；然而，Nrf2 信号的诱导引发了包括 NAD(P)H：醌氧化还原酶-1（NQO1）和谷胱甘肽-S-转移酶-P1（GST-P1）和 Kelch 样 ECH 相关蛋白 1（Keap1）在内的细胞防御机制的上调。在 HepG2 细胞中，“NO 特异性”4,5-二氨基荧光素报告物 DAF-DA 对 NO-ASA 和 X-ASA 有反应，QM 诱导的氧化应激伪装成 NO。LC-MS/MS 分析表明，蛋白质的半胱氨酸残基包括谷胱甘肽-S-转移酶-P1（GST-P1）和 Kelch 样 ECH 相关蛋白 1（Keap1）被有效地烷基化。获得了与 Nrf2 易位到核、核内 Nrf2 易位、抗氧化反应元件（ARE）激活和细胞保护靶基因上调相关的 Keap1 半胱氨酸残基的烷基化证据。至少在细胞培养物中，pNO-ASA 作为 QM 供体，通过细胞酯酶活性生物转化为水杨酸盐、NO(3)(-) 和亲电 QM。最后，合成了两种新型阿司匹林前药，它们都是 ARE 的有效激活剂，设计用于生物转化时仅释放 QM 和水杨酸盐。目前对通过 Nrf2 信号作用的亲电药物的兴趣表明，QM 供体型杂合药物可以作为药物发现中的信息化学探针。
