Covalent modification of Keap1 Cys489 by NU6300 activates Nrf2 signaling and suppresses NLRP3 inflammasome-mediated pyroptosis

Xueqin Jiang; Hongyu Zheng; Xinlu Zhang; Minghai Tang; Jing Peng; Xiaoying Cai; Kaiyue Su; Ruijia Zhang; Neng Ye; Lei Lin; Rupei Ma; Caiyun Shen; Wenshuang Wu; Haoyu Ye

doi:10.1016/j.jpha.2025.101458

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Xueqin Jiang, Hongyu Zheng, Xinlu Zhang, Minghai Tang, Jing Peng, Xiaoying Cai, Kaiyue Su, Ruijia Zhang, Neng Ye, Lei Lin, Rupei Ma, Caiyun Shen, Wenshuang Wu, Haoyu Ye. Covalent modification of Keap1 Cys489 by NU6300 activates Nrf2 signaling and suppresses NLRP3 inflammasome-mediated pyroptosis[J]. Journal of Pharmaceutical Analysis. doi: 10.1016/j.jpha.2025.101458

Citation:

Xueqin Jiang, Hongyu Zheng, Xinlu Zhang, Minghai Tang, Jing Peng, Xiaoying Cai, Kaiyue Su, Ruijia Zhang, Neng Ye, Lei Lin, Rupei Ma, Caiyun Shen, Wenshuang Wu, Haoyu Ye. Covalent modification of Keap1 Cys489 by NU6300 activates Nrf2 signaling and suppresses NLRP3 inflammasome-mediated pyroptosis[J]. Journal of Pharmaceutical Analysis. doi: 10.1016/j.jpha.2025.101458

Citation:

Xueqin Jiang, Hongyu Zheng, Xinlu Zhang, Minghai Tang, Jing Peng, Xiaoying Cai, Kaiyue Su, Ruijia Zhang, Neng Ye, Lei Lin, Rupei Ma, Caiyun Shen, Wenshuang Wu, Haoyu Ye. Covalent modification of Keap1 Cys489 by NU6300 activates Nrf2 signaling and suppresses NLRP3 inflammasome-mediated pyroptosis[J]. Journal of Pharmaceutical Analysis. doi: 10.1016/j.jpha.2025.101458

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Covalent modification of Keap1 Cys489 by NU6300 activates Nrf2 signaling and suppresses NLRP3 inflammasome-mediated pyroptosis

doi: 10.1016/j.jpha.2025.101458

a. Department of Biotherapy, Cancer Center and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China;
b. School of Pharmacy, Chengdu Medical College, Chengdu, 610500, China;
c. Scaled Manufacturing Center of Biological Products, Management Office of National Facility for Translational Medicine, West China Hospital, Sichuan University, Chengdu, 610041, China;
d. Division of Thyroid Surgery, Department of General Surgery and Laboratory of Thyroid and Parathyroid Disease, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, 610041, China

Funds:

This study was supported by the National Natural Science Foundation of China (Grant No.: 82473776) and the Science and Technology Department of Sichuan Province (Grant Nos.: 2024YFHZ0185 and 2024NSFSC1871). We sincerely thank Jingyao Zhang from the Core Facilities of West China Hospital, Sichuan University, and Cheng He from Bailebo Biotechnology Co., Ltd. for their technical support in the SPR experiments.

Received Date: Jun. 30, 2025
Accepted Date: Sep. 29, 2025
Rev Recd Date: Sep. 29, 2025
Available Online: Oct. 10, 2025

Abstract

Abstract

Nuclear factor erythroid 2-related factor 2 (Nrf2), a master regulator of oxidative stress and inflammasome, plays a critical role in modulating pyroptosis. In this study, we identified NU6300 as a novel small-molecule activator of Nrf2 that restores mitochondrial function, alleviates oxidative stress, and suppresses inflammasome activation and pyroptosis. Mechanistically, NU6300 covalently modified Kelch-like ECH-associated protein 1 (Keap1) at cysteine-489, disrupting the Keap1-Nrf2 interaction, thereby promoting Nrf2 nuclear translocation and transcription of antioxidant genes. Notably, NU6300 inhibits NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome activation and gasdermin D (GSDMD)-mediated pyroptosis through redox-dependent mechanisms, representing the first evidence that covalent modification of Keap1 at cysteine-489 by NU6300 bridges Nrf2 activation and inflammasome suppression. In vivo, NU6300 exhibits potent antioxidant and anti-inflammatory protection against acetaminophen-induced acute liver injury in mice. Collectively, these findings demonstrate that NU6300 is a novel Nrf2 activator and offers a promising therapeutic strategy for pyroptosis-driven inflammatory diseases.
- Pyroptosis,
- Keap1-Nrf2,
- NU6300,
- NLRP3 inflammasome,
- Liver injury

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References(49)

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