Kaihua Yu,1,* Yunfei Gu,2,* Ying Yao,1 Jianchun Li,3 Suheng Chen,1 Hong Guo,4 Yulan Li,5 Jian Liu1,6 

1The First School of Clinical Medicine, Lanzhou University, Lanzhou, Gansu, People’s Republic of China; 2Anesthesiology Department, Gansu Provincial Maternity and Child-Care Hospital (Gansu Provincial Center Hospital), Lanzhou, Gansu, People’s Republic of China; 3Department of Intensive Care Unit, Suzhou Science and Technology City Hospital, Nanjing, Jiangsu, People’s Republic of China; 4Department of Anesthesiology, Inner Mongolia Hospital of Peking University Cancer Hospital, Hohhot, Inner Mongolia, People’s Republic of China; 5Department of Anesthesiology, First Hospital of Lanzhou University, Lanzhou, Gansu, People’s Republic of China; 6Gansu Provincial Maternity and Child-Care Hospital (Gansu Provincial Center Hospital), Lanzhou, Gansu, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Jian Liu; Yulan Li, Email medecinliujian@163.com; liyul@lzu.edu.cn

Background: Oxygen supplementation is essential for patients with a multitude of diseases but can cause severe hyperoxia-induced lung injury (HLI), necessitating the identification of therapeutic targets to improve clinical outcomes. Cuproptosis, a novel copper-dependent form of cell death characterized by proteotoxic stress resulting from lipoylated protein aggregation and loss of iron-sulfur cluster proteins, is distinct from other forms of cell death. However, the role of cuproptosis in HLI remains unclear.
Methods: We established an HLI model in MLE-12 cells and C57BL/6 mice to investigate the involvement of cuproptosis in hyperoxia-induced toxicity.
Results: We observed a time-dependent increase in the cuproptosis-related gene Fdx1 under hyperoxia. Moreover, hyperoxia activated the membrane-associated copper transporter SLC31A1 and significantly elevated copper levels in MLE-12 cells, as well as in the serum and lung tissue of C57BL/6 mice. Further analysis revealed that hyperoxia significantly altered the expression of cuproptosis-related genes without affecting DLAT levels, but significantly increased lipoylated-DLAT levels. ELISA, CCK-8 assays, HE staining, lung wet-to-dry weight ratio, and bronchoalveolar lavage fluid analysis demonstrated that treatment with the cuproptosis inhibitor TTM reduced pro-inflammatory cytokines (TNF-α and IL-1β) and alleviated hyperoxia-induced injury in both MLE-12 cells and C57BL/6 mice.
Conclusion: Our study identifies the involvement of cuproptosis in HLI, providing new insights into the pathogenesis of hyperoxic lung injury and potential therapeutic strategies.

Keywords: hyperoxia, lung injury, hyperoxia-induced lung injury, cuproptosis, copper, FDX1