N-acetyl-l-cysteine (NAC) is a medication and a widely used antioxidant in cell death research. Despite its somewhat obscure mechanism of action, its role in inhibiting ferroptosis is gaining increasi Show more
N-acetyl-l-cysteine (NAC) is a medication and a widely used antioxidant in cell death research. Despite its somewhat obscure mechanism of action, its role in inhibiting ferroptosis is gaining increasing recognition. In this study, we demonstrate that NAC treatment rapidly replenishes the intracellular cysteine pool, reinforcing its function as a prodrug for cysteine. Interestingly, its enantiomer, N-acetyl-d-cysteine (d-NAC), which cannot be converted into cysteine, also exhibits a strong anti-ferroptotic effect. We further clarify that NAC, d-NAC, and cysteine all act as direct reducing substrates for GPX4, counteracting lipid peroxidation. Consequently, only GPX4-rather than system xc-, glutathione biosynthesis, or ferroptosis suppressor protein 1-is necessary for NAC and d-NAC to prevent ferroptosis. Additionally, we identify a broad range of reducing substrates for GPX4 in vitro, including β-mercaptoethanol. These findings provide new insights into the mechanisms underlying the protective effects of NAC and other potential GPX4-reducing substrates against ferroptosis. Show less
Lung cancer is a common malignant tumor that occurs in the human body and poses a serious threat to human health and quality of life. The existing treatment methods mainly include surgical treatment, Show more
Lung cancer is a common malignant tumor that occurs in the human body and poses a serious threat to human health and quality of life. The existing treatment methods mainly include surgical treatment, chemotherapy, and radiotherapy. However, due to the strong metastatic characteristics of lung cancer and the emergence of related drug resistance and radiation resistance, the overall survival rate of lung cancer patients is not ideal. There is an urgent need to develop new treatment strategies or new effective drugs to treat lung cancer. Ferroptosis, a novel type of programmed cell death, is different from the traditional cell death pathways such as apoptosis, necrosis, pyroptosis and so on. It is caused by the increase of iron-dependent reactive oxygen species due to intracellular iron overload, which leads to the accumulation of lipid peroxides, thus inducing cell membrane oxidative damage, affecting the normal life process of cells, and finally promoting the process of ferroptosis. The regulation of ferroptosis is closely related to the normal physiological process of cells, and it involves iron metabolism, lipid metabolism, and the balance between oxygen-free radical reaction and lipid peroxidation. A large number of studies have confirmed that ferroptosis is a result of the combined action of the cellular oxidation/antioxidant system and cell membrane damage/repair, which has great potential application in tumor therapy. Therefore, this review aims to explore potential therapeutic targets for ferroptosis in lung cancer by clarifying the regulatory pathway of ferroptosis. Based on the study of ferroptosis, the regulation mechanism of ferroptosis in lung cancer was understood and the existing chemical drugs and natural compounds targeting ferroptosis in lung cancer were summarized, with the aim of providing new ideas for the treatment of lung cancer. In addition, it also provides the basis for the discovery and clinical application of chemical drugs and natural compounds targeting ferroptosis to effectively treat lung cancer. Show less