Long-chain acyl-coenzyme A (CoA) synthase 4 (ACSL4) is an enzyme that esterifies CoA into specific polyunsaturated fatty acids, such as arachidonic acid and adrenic acid. Based on accumulated evidence, the ACSL4-catalyzed biosynthesis of arachidonoyl-CoA contributes to the execution of ferroptosis by triggering phospholipid peroxidation. Ferroptosis is a type of programmed cell death caused by iron-dependent peroxidation of lipids; ACSL4 and glutathione peroxidase 4 positively and negatively regulate ferroptosis, respectively. In addition, ACSL4 is an essential regulator of fatty acid (FA) metabolism. ACSL4 remodels the phospholipid composition of cell membranes, regulates steroidogenesis, and balances eicosanoid biosynthesis. In addition, ACSL4-mediated metabolic reprogramming and antitumor immunity have attracted much attention in cancer biology. Because it facilitates the cross-talk between ferroptosis and FA metabolism, ACSL4 is also a research hotspot in metabolic diseases and ischemia/reperfusion injuries. In this review, we focus on the structure, biological function, and unique role of ASCL4 in various human diseases. Finally, we propose that ACSL4 might be a potential therapeutic target.
Humans ; Ferroptosis ; Apoptosis ; Phospholipids/metabolism* ; Nitric Oxide Synthase

BACKGROUND: Gallbladder cancer (GBC) is the most common malignant tumor of biliary tract. Isoliquiritigenin (ISL) is a natural compound with chalcone structure extracted from the roots of licorice and other plants. Relevant studies have shown that ISL has a strong anti-tumor ability in various types of tumors. However, the research of ISL against GBC has not been reported, which needs to be further investigated. METHODS: The effects of ISL against GBC cells in vitro and in vivo were characterized by cytotoxicity test, RNA-sequencing, quantitative real-time polymerase chain reaction, reactive oxygen species (ROS) detection, lipid peroxidation detection, ferrous ion detection, glutathione disulphide/glutathione (GSSG/GSH) detection, lentivirus transfection, nude mice tumorigenesis experiment and immunohistochemistry. RESULTS: ISL significantly inhibited the proliferation of GBC cells in vitro . The results of transcriptome sequencing and bioinformatics analysis showed that ferroptosis was the main pathway of ISL inhibiting the proliferation of GBC, and HMOX1 and GPX4 were the key molecules of ISL-induced ferroptosis. Knockdown of HMOX1 or overexpression of GPX4 can reduce the sensitivity of GBC cells to ISL-induced ferroptosis and significantly restore the viability of GBC cells. Moreover, ISL significantly reversed the iron content, ROS level, lipid peroxidation level and GSSG/GSH ratio of GBC cells. Finally, ISL significantly inhibited the growth of GBC in vivo and regulated the ferroptosis of GBC by mediating HMOX1 and GPX4 . CONCLUSION ISL induced ferroptosis in GBC mainly by activating p62-Keap1-Nrf2-HMOX1 signaling pathway and down-regulating GPX4 in vitro and in vivo . This evidence may provide a new direction for the treatment of GBC.
Animals ; Mice ; Carcinoma in Situ ; Chalcones/pharmacology* ; Ferroptosis ; Gallbladder Neoplasms/genetics* ; Glutathione Disulfide ; Kelch-Like ECH-Associated Protein 1 ; Mice, Nude ; NF-E2-Related Factor 2/genetics* ; Reactive Oxygen Species ; Humans

Ferroptosis is a new type of programmed cell death different from other cell death pathways such as apoptosis,autophagy,necrosis,and pyroptosis in terms of initiation,mechanisms,and molecular characteristics.As the accumulation of phospholipid hydroperoxides is the hallmark of ferroptosis,the balance between oxidative damage and antioxidant defense is critical to the regulatory mechanism of ferroptosis.In cancer,the upregulation of antioxidant defense pathways can inhibit ferroptosis,thereby promoting cancer cells to survive the oxidative stress and develop drug resistance.This review systematically introduces the main features and regulatory mechanisms of ferroptosis.In addition,we summarize the role of ferroptosis in the progression and drug resistance of malignant tumors,providing novel implications for further research on the pathogenesis of malignant tumors and discovery of new targets for anti-cancer therapy.
Humans ; Ferroptosis ; Antioxidants ; Apoptosis ; Neoplasms ; Autophagy

Chronic heart failure is the end stage of heart diseases caused by multiple causes. Myocardial cell injury is the key cause of cardiac function deterioration. Ferroptosis, an iron-dependent programmed death mode, is characterized by iron overload and excessive accumulation of lipid peroxides. Studies have demonstrated that inhibiting ferroptosis has a protective effect on myocardial cells. The theory of "harmful hyperactivity and responding inhibition" is an important rule developed by physicians to explain the generation and restriction of the five elements and the pathological imbalance of the human body, and can guide medication. Correlating with the nature, humans need to rely on the law of responding inhibition to maintain the harmony of five Zang-organs and the steady state of Fu-organs. The pathogenesis of ferroptosis in chronic heart failure highly coincides with the process of failing to "inhibition and hyperactivity becoming harmful". The initial factor of ferroptosis is the deficiency of heart Qi, which results in the inability to maintain the balance of cardiomyocyte redox system. The involvement of the five Zang-organs leads to the loss of distribution of body fluid and blood. As a result, the phlegm turbidity, blood stasis, and water retention in the meridians occur, which are manifested as the accumulation of iron and lipid peroxides, which is the aggravating factor of ferroptosis. The two factors interact with each other, leading to the spiral development and thus aggravating heart failure. According to the traditional Chinese medicine(TCM) pathogenesis of ferroptosis, the authors try to treat the chronic heart failure by stages in accordance with the general principle of restraining excess and alleviating hyperactivity. The early-stage treatment should "nourish heart Qi, regulate the five Zang-organs, so as to restrain excess". The middle-stage treatment should "active blood, resolve phlegm, dispel pathogen, and eliminate turbidity", so as to alleviate hyperactivity. The late-stage treatment should "warm Yang, replenish Qi, active blood, and excrete water". Following the characteristics of pathogenesis, the TCM intervention can reduce iron accumulation and promote the clearance of lipid peroxide, thus inhibiting ferroptosis and improving cardiac function.
Humans ; Ferroptosis ; Lipid Peroxides ; Medicine, Chinese Traditional ; Heart Failure/drug therapy* ; Chronic Disease ; Iron ; Water

This study aims to investigate the pathogenesis of chronic heart failure based on ferroptosis-mediated oxidative stress and predict the targets of Shenfu Injection in treating chronic heart failure. A rat model of chronic heart failure was established by the isoproterenol induction method. According to the random number table method, the modeled rats were assigned into three groups: a model group, a Shenfu Injection group, and a ferrostatin-1(ferroptosis inhibitor) group. In addition, a normal group was designed. After 15 days of intervention, the cardiac mass index and left ventricular mass index were determined. Echocardiography was employed to eva-luate the cardiac function. Hematoxylin-eosin staining and Masson staining were employed to reveal the pathological changes and fibrosis of the heart, and Prussian blue staining to detect the aggregation of iron ions in the myocardial tissue. Transmission electron microscopy was employed to observe the mitochondrion ultrastructure in the myocardial tissue. Colorimetry was adopted to measure the levels of iron metabolism, lipid peroxidation, and antioxidant indicators. Flow cytometry was employed to measure the content of lipid-reactive oxygen species(ROS) and the fluorescence intensity of ROS. Western blot and RT-qPCR were employed to determine the protein and mRNA levels, respectively, of ferroptosis-related factors in the myocardial tissue. The results showed that the rats in the model group had reduced cardiac function, elevated levels of total iron and Fe~(2+), lowered level of glutathione(GSH), increased malondialdehyde(MDA), decreased superoxide dismutase(SOD) and glutathione peroxidase(GSH-Px), and rising levels of ROS and lipid-ROS. In addition, the model group showed fibrous tissue hyperplasia with inflammatory cell infiltration and myocardial fibrosis, iron ion aggregation, and characteristic mitochondrial changes specific for iron death. Moreover, the model group showcased upregulated protein and mRNA levels of p53 and COX2 and downregulated protein and mRNA levels of GPX4, FTH1, SLC7A11, and Nrf2 in the myocardial tissue. The intervention with Shenfu Injection significantly improved the cardiac function, recovered the iron metabolism, lipid peroxidation, and antioxidant indicators, decreased iron deposition, improved mitochondrial structure and function, and alleviated inflammatory cell infiltration and fibrosis. Furthermore, Shenfu Injection downregulated the mRNA and protein levels of p53 and COX2 and upregulated the mRNA and protein levels of GPX4, FTH1, SLC7A11, and Nrf2 in the myocardial tissue. Shenfu Injection can improve the cardiac function by regulating iron metabolism, inhibiting ferroptosis, and reducing oxidative stress injury.
Animals ; Rats ; Antioxidants ; Reactive Oxygen Species ; Cyclooxygenase 2 ; Ferroptosis ; NF-E2-Related Factor 2 ; Tumor Suppressor Protein p53 ; Heart Failure/genetics* ; Oxidative Stress ; Chronic Disease ; Glutathione ; Fibrosis ; Iron ; RNA, Messenger ; Lipids

This study aims to explore the effects of Shenqi Dihuang Decoction on high-glucose induced ferroptosis and the nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)/glutathione peroxidase 4(GPX4) axis in human renal tubular epithelial cells(HK-2) and to clarify the underlying mechanism. The cell injury model was established by exposing HK-2 to high glucose, and the Shenqi Dihuang Decoction-medicated serum was prepared. The optimal concentration and intervention time of Shenqi Dihuang Decoction were determined. HK-2 were divided into normal, high glucose, and low-, medium-, and high-dose Shenqi Dihuang Decoction groups. After interventions, the cell proliferation rate in each group was determined and the cell morphology and mitochondrial ultrastructure were observed. Then, the levels of intracellular reactive oxygen species(ROS), ferrous ion(Fe~(2+)), glutathione(GSH), and malondialdehyde(MDA) and the protein levels of Nrf2, HO-1, GPX4, and xCT were measured. The optimal concentration and intervention time of Shenqi Dihuang Decoction-medicated serum were determined to be 10% and 24 h, respectively. Compared with the high glucose group, high-dose Shenqi Dihuang Decoction promoted the proliferation of HK-2. The cells in the low-, medium-, and high-dose Shenqi Dihuang Decoction groups presented tight arrangement, an increased cell count, improved morphology from a spindle-fiber shape to a cobblestone shape, and improved morphology and structure of mitochondrial membrane and cristae, compared with those in the high glucose group. Meanwhile, all the doses of Shenqi Dihuang Decoction inhibited ROS elevation to mitigate the peroxidation damage, lowered the Fe~(2+) and MDA levels and elevated the GSH level to inhibit lipid peroxidation, and activated the antioxidant pathway to upregulate the protein levels of Nrf2, HO-1, xCT, and GPX4. In conclusion, Shenqi Dihuang Decoction-medicated serum can inhibit high-glucose induced ferroptosis of HK-2 in vitro, which involves the antioxidant effect and the activation of the Nrf2/HO-1/GPX4 pathway.
Humans ; Ferroptosis ; NF-E2-Related Factor 2/genetics* ; Reactive Oxygen Species ; Epithelial Cells ; Antioxidants ; Glutathione ; Glucose

Objective To investigate the effects of YAP on the occurrence and progression of acute liver failure by regulating the ferroptosis pathway and its underlying mechanism. Methods A total of 20 8-week-old C57BL/6 mice were randomly divided into four groups: a control group, an acute liver failure model group, a YAP agonist XMU-MP-1 treatment group and a YAP inhibitor verteporfin treatment group, five mice for each group. HE staining was used to observe the pathological changes of hepatic inflammation and necrosis. Plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were detected by liver biochemistry. Iron (Fe), malondialdehyde (MDA), glutathione (GSH) determination kits were used to measure their levels in liver tissues of each group. The changes of hepatocyte mitochondrial in each group were observed by electron microscopy. Real time PCR and Western blot analysis were used to detect the mRNA and protein expressions of YAP, glutathione peroxidase 4 (GPX4) and 5-lipoxygenase (5-LOX). Results Compared with the control group, mice in the acute liver failure model group and the YAP inhibitor verteporfin treatment group showed severe liver tissue congestion with inflammatory cell infiltration and structural damage to hepatic lobules. Liver injury was alleviated in the XMU-MP-1 treatment group. With the occurrence of liver failure, plasma ALT and AST levels significantly increased, and liver function was improved in XMU-MP-1 treatment group. Electron microscopy showed that mitochondria in hepatocytes of mice with liver failure became smaller and bilayer membrane density increased, while mitochondria changes in the XMU-MP-1 group were alleviated. In addition, the acute liver failure model group showed an increase in Fe and MDA contents, decreased protein expressions of GPX4, and enhanced expression of 5-LOX, suggesting that ferroptosis was involved in acute liver failure in C57BL/6 mice. Ferroptosis was inhibited by activation of YAP. Conclusion Activation of YAP may ameliorate liver injury by inhibiting ferroptosis.
Animals ; Mice ; Ferroptosis ; Glutathione ; Liver Failure ; Liver Failure, Acute/drug therapy* ; Mice, Inbred C57BL ; Verteporfin ; YAP-Signaling Proteins/metabolism*

Lung cancer is one of the most common cancers in the world, and its treatment strategy is mainly surgery combined with radiotherapy and chemotherapy. However, long-term chemotherapy will result in drug resistance, which is also one of the difficulties in the treatment of lung cancer. Ferroptosis is an iron-dependent and lipid peroxidation-driven non-apoptotic cell death cascade, occurring when there is an imbalance of redox homeostasis in the cell. Nuclear factor erythroid 2-related factor 2 (Nrf2) is key for cellular antioxidant responses. Numerous studies suggest that Nrf2 assumes an extremely important role in regulation of ferroptosis, for its various functions in iron, lipid, and amino acid metabolism, and so on. In this review, a brief overview of the research progress of ferroptosis over the past decade will be presented. In particular, the mechanism of ferroptosis and the regulation of ferroptosis by Nrf2 will be discussed, as well as the role of the Nrf2 pathway and ferroptosis in tumor drug resistance, which will provide new research directions for the treatment of drug-resistant lung cancer patients.
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Humans ; Ferroptosis ; NF-E2-Related Factor 2/genetics* ; Lung Neoplasms/genetics* ; Drug Resistance, Neoplasm ; Iron

BACKGROUND: Lung adenocarcinoma (LUAD) is the most common type of non-small cell lung cancer, and any change of miRNAs expression will affect the degree of target regulation, thus affecting intracellular homeostasis. This study verified that miR-186-5p could inhibit the proliferation, migration and invasion of LUAD cells by regulating PRKAA2. METHODS: Previous investigations found that the expression of miR-186-5p was markedly suppressed in LUAD. Bioinformatics method is used to predict the target protein related to ferroptosis downstream and inquire about its expression level in LUAD and its influence on the survival of patients. Double luciferase verified the binding site of PRKAA2 and miR-186-5p. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were used to detect the expression of PRKAA2. The effects of miR-186-5p of LUAD cells as well as the mechanism by which miR-186-5p inhibits Fer-1's sensitivity to ferroptosis were confirmed by EdU, Transwell, and scratch assays. The effect of miR-186-5p on the amount of reactive oxygen species (ROS) in LUAD cells was discovered using ROS experiment. Malondialdehyde (MDA) and glutathione (GSH) experiments were used to detect the effects of miR-186-5p and PRKAA2 on ferroptosis index of LUAD cells. The concentration of lipid ROS (L-ROS) in LUAD cells were measured using the L-ROS tests to determine the effects of miR-186-5p and PRKAA2. RESULTS: The expression of PRKAA2 is up-regulated, and a high level of PRKAA2 expression was associated with a poor prognosis for patients with LUAD. Overexpression of miR-186-5p decreased the gene and protein expression of PRKAA2. By promoting ferroptosis, miR-186-5p overexpression prevented lung cancer cells from proliferating, invading, and migrating. ROS could be produced in higher amounts in LUAD cells due to miR-186-5p. Overexpression of miR-186-5p and knockdown PRKAA2 up-regulated MDA content and reduced GSH content in LUAD cells, respectively. miR-186-5p could increase the content of L-ROS and promote the ferroptosis sensitivity of LUAD cells by targeting PRKAA2. CONCLUSIONS miR-186-5p promotes ferroptosis of LUAD cells through targeted regulation of PRKAA2, thus inhibiting the proliferation, invasion and migration of LUAD.
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Humans ; Lung Neoplasms/genetics* ; Carcinoma, Non-Small-Cell Lung ; Ferroptosis/genetics* ; Reactive Oxygen Species ; Adenocarcinoma of Lung/genetics* ; MicroRNAs/genetics* ; 3,4-Methylenedioxyamphetamine ; Cell Proliferation/genetics* ; Cell Movement/genetics* ; Gene Expression Regulation, Neoplastic ; Cell Line, Tumor ; AMP-Activated Protein Kinases

自噬是细胞内一种高度保守的生理过程，可通过溶酶体系统降解过量或受损的细胞器、有毒的蛋白聚集体和病原体等。最新研究表明，海马钙素样1（HPCAL1）可作为特异性自噬受体和铁死亡的正调节因子。HPCAL1可选择性降解钙粘素2（CDH2），加速脂质过氧化，促进癌细胞铁死亡。iHPCAL1是抑制HPCAL1的小分子化合物，可抑制Erastin诱导的肿瘤细胞铁死亡。此外，它还可以抑制铁死亡诱导的急性胰腺炎。本文通过对HPCAL1在铁死亡中的具体作用机制进行概述，为HPCAL1作为铁死亡相关疾病的潜在治疗靶点提供新思路和理论依据。
Ferroptosis ; Cell Line, Tumor ; Autophagy