Phospholipase D regulates ferroptosis signal transduction in mouse spleen hypoxia response

High-altitude hypoxia exposure can lead to phospholipase D-mediated lipid metabolism disorder in spleen tissues and induce ferroptosis. Nonetheless, the key genes underlying hypoxia-induced splenic phospholipase D and the ferroptosis pathway remain unclear. This study aimed to establish a hypoxia animal model. Combined transcriptomic and proteomic analyses showed that 95 predicted target genes (proteins) were significantly differentially expressed under hypoxic conditions. Key genes in phospholipase D and ferroptosis pathways under hypoxic exposure were identified by combining Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis techniques. Gene set enrichment analysis (GSEA) showed that the differential gene sets of the phospholipase D and ferroptosis signaling pathways were upregulated in the high-altitude hypoxia group. The genes in the phospholipase D signalling pathway were verified, and the expression levels of KIT and DGKG were upregulated in spleen tissues under hypoxic exposure. Subsequently, the mRNA and protein expression levels of genes from the exogenous pathway such as TFRC, SLC40A1, SLC7A11, TRP53, and FTH1 and those from the endogenous pathway such as GPX4, HMOX1, and ALOX15 differentials in the ferroptosis signalling pathway were verified, and the results indicated significant differential expression. In summary, exposure to high-altitude hypoxia mediated phospholipid metabolism disturbance through the phospholipase D signalling pathway and further induced ferroptosis, leading to splenic injury.

Menaquinone-4 exerts a protective effect against carbon tetrachloride-induced acute liver injury in mice by alleviating ferroptosis / 临床肝胆病杂志

ObjectiveTo investigate whether menaquinone-4 （MK-4） can exert a protective effect against carbon tetrachloride （CCl4）-induced acute liver injury （ALI） in mice by alleviating ferroptosis. MethodsAfter adaptive feeding， adult male ICR mice， aged 8 weeks， were divided into Control group， MK-4 group， CCl4 model group （6-hour， 12-hour， and 24-hour）， and MK-4+CCl4 group （6-hour， 12-hour， and 24-hour）， with 6 mice in each group. The mice in the Control group were given intraperitoneal injection of an equal dose of corn oil； the mice in the MK-4 group were given intraperitoneal injection of 40 mg/kg MK-4 solution， followed by an equal dose of corn oil after 1 hour； the mice in the MK-4+CCl4 group （6-hour， 12-hour， and 24-hour） were given intraperitoneal injection of 40 mg/kg MK-4 solution， and after 1 hour， the mice in this group and the CCl4 model group （6-hour， 12-hour， and 24-hour） were given intraperitoneal injection of 0.3 mL/kg CCl4 solution， with samples collected at 6， 12， and 24 hours. HE staining was used to observe the pathological changes of mouse liver； Prussian blue staining was used to observe iron accumulation in liver tissue； a biochemical analyzer was used to measure the serum levels of aspartate aminotransferase （AST） and alanine aminotransferase （ALT）； related kits were used to measure the levels of tissue iron content and the oxidative stress indices malondialdehyde （MDA） and glutathione （GSH） in liver homogenate； RT-PCR was used to measure the expression levels of ferroptosis marker genes （acyl-CoA synthetase long-chain family member 4 ［ACSL4］， prostaglandin-endoperoxide synthase 2 ［PTGS2］， and glutathione peroxidase 4 ［GPX4］） and iron metabolism-related genes （hemojuvelin ［HJV］， transferrin receptor 1 ［TFR1］， and ferroportin ［FPN］）， and Western blot was used to measure the protein expression level of GPX4. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the least significant difference t-test was used for further comparison between two groups. ResultsIn the aging study， compared with the Control group， the CCl4 model group （6-hour， 12-hour， and 24-hour） had significant increases in liver weight coefficient and the serum levels of ALT and AST （all P<0.05）， and HE staining also showed that liver injury gradually aggravated over time. Meanwhile， compared with the CCl4 model group （6-hour， 12-hour， and 24-hour）， the MK-4+CCl4 （12-hour） group had significant reductions in liver weight coefficient and the serum levels of ALT and AST （all P<0.05）， with a reduction in the necrotic area of liver tissue， and therefore， 12-hour mouse tissue samples were used for detection in the following study. Compared with the Control group， the CCl4 group had a significant increase in MDA and a significant reduction in GSH （both P<0.05）， and compared with the CCl4 group， the MK-4+CCl4 group had a significant reduction in MDA and a significant increase in GSH （both P<0.05）. Compared with the Control group， the CCl4 group had significant increases in the key ferroptosis indices ASCL4 and PTGS2 and a significant reduction in GPX4 （all P<0.05）； compared with the CCl4 group， the MK-4+CCl4 group had significant reductions in the mRNA expression levels of ASCL4 and PTGS2 and a significant increase in the mRNA expression level of GPX4 （all P<0.05）. Western blotting showed that compared with the Control group， the CCl4 group had a significant reduction in the protein expression level of GPX4 （P<0.05）， and compared with the CCl4 group， the MK-4+CCl4 group had a significant increase in the protein expression level of GPX4 （P<0.05）. Prussian blue staining showed that compared with the Control group， the CCl4 group had a significant increase in iron accumulation； after MK-4 intervention， compared with the CCl4 group， the MK-4+CCl4 group had a significant reduction in iron accumulation. As for the measurement of iron metabolism genes in mouse liver， compared with the Control group， the CCl4 group had a significant increase in iron content， significant reductions in the mRNA expression levels of FPN and HJV， and a significant increase in the mRNA expression level of TFR1 （all P<0.05）； after protection with MK-4， there was a significant reduction in iron content， significant increases in the mRNA expression levels of FPN and HJV， and a significant reduction in the mRNA expression level of TFR1 （all P<0.05）. ConclusionMK-4 intervention in advance can alleviate CCl4-induced ALI in mice， possibly by inhibiting ferroptosis and improving the expression of iron metabolism-related genes in mouse liver.

Dendrobii Caulis Mixture-containing Serum Protects Mice from Podocyte Injury Induced by High Glucose / 中国实验方剂学杂志

ObjectiveTo investigate the effect and mechanism of Dendrobium mixture （DMix）-containing serum on high glucose-induced podocyte injury in mice. MethodThe MPC5 mouse glomerular podocytes were cultured in vitro， and the optimal glucose concentration for modeling， modeling time， and concentration of DMix-containing serum for administration were determined. The cells were classified into normal （5.5 mmol·L-1 glucose+10% blank serum）， model （30 mmol·L-1 glucose+10% blank serum）， DMix-containing serum （30 mmol·L-1 glucose+10% DMix-containing serum）， ferroptosis inhibitor （Fer-1， 30 mmol·L-1 glucose+10% blank serum+1 μmol·L-1 Fer-1） groups. The corresponding kits were used to measure the levels of Fe2+ and lactate dehydrogenase （LDH） in cells. Enzyme-linked immunosorbent assay was employed to determine the content of glutathione （GSH） and lipid peroxide （LPO） in cells. Fluorescence probe was used to measure the reactive oxygen species （ROS） level. Real-time fluorescence quantitative polymerase chain reaction and Western blotting were employed to determine the mRNA and protein levels， respectively， of Wilms' tumor-1 （WT-1）， desmin， long chain acyl-CoA synthase 4 （ACSL4）， and glutathione peroxidase 4 （GPX4） in podocytes. ResultCompared with the blank group， the intervention with 30 mmol·L-1 glucose for 48 h reduced podocyte viability （P<0.01）， and the 10% DMix-containing serum showed the most significant improvement in podocyte viability （P<0.01）. Compared with the normal group， the model group presented elevated levels of Fe2+， LDH， LPO， and ROS， lowered GSH level， up-regulated mRNA and protein levels of desmin and ACSL4， and down-regulated mRNA and protein levels of WT-1 and GPX4 （P<0.01）. Compared with the model group， the DMix-containing serum lowered the Fe2+， LDH， LPO， and ROS levels， elevated the GSH level， down-regulated the mRNA and protein levels of desmin and ACSL4， and up-regulated the mRNA and protein levels of WT-1 and GPX4 in podocytes （P<0.05， P<0.01）. ConclusionDMix-containing serum exerts a protective effect on high glucose-induced podocyte injury by inhibiting ferroptosis.

Progress on the relationship of aldehyde dehydrogenase 2 with human diseases and its small-molecule activators / 药学实践杂志

Aldehyde dehydrogenase 2 (ALDH2) is one of important factors against from the damage under oxidative stress in human body. A high proportion of East Asians carry ALDH2 inactive mutation gene. There are many diseases closely related to ALDH2, such as cardiovascular diseases, neurodegenerative diseases and liver diseases. Recent studies also have found that ALDH2 is associated with ferroptosis. Therefore, ALDH2 has becoming a potential target for the treatment of the above related diseases. Several types of small molecule activators with potential value of clinical application have been reported. The research progress on the structure and function of ALDH2 , the relationship with human diseases and its activators were summarized in this paper.

Mechanism of Ferroptosis in Myocardial Cells and Protective Effect of Traditional Chinese Medicine / 中国实验方剂学杂志

Ferroptosis is a new type of programmed cell death， characterized by iron overload and lipid peroxidation. Cardiovascular disease （CVD） is an ischemic or hemorrhagic disease of the heart caused by various factors， mainly including myocardial infarction， heart failure， etc. Ferroptosis is involved in the process of myocardial cell damage and plays a driving role in the progression of various CVDs. Its main mechanisms include the destruction of iron homeostasis， the production of reactive oxygen species， the disorder of the antioxidant system， mitochondrial membrane damage， endoplasmic reticulum stress， tumor suppressor gene p53， transcription factor Nrf2 pathway， etc. Myocardial injury is one of the causes of death in many patients with heart disease. Monomers or compounds of traditional Chinese medicine have shown good effects in the treatment of myocardial cell injury caused by ferroptosis， including baicalin protecting cardiac microvascular endothelial cells of myocardial ischemia-reperfusion （I/R） rats through intracellular phosphatidylinositol kinase/phosphokinase B/endothelial nitric oxide synthase （PI3K/Akt/eNOS） pathway， Aralia elata saponin inhibiting myocardial cell ferroptosis through glucocorticoid receptor/p53/solute carrier family 7 members 11 （NR3C1/p53/SLC7A11） pathway， Xinyang tablets improving oxidative stress by regulating phosphorylated serine/threonine protein kinase/stress-activated protein kinase/p53 （MLK3/JNK/p53） signaling pathway. It is of great significance to explore the mechanism of ferroptosis and the protective effect of related traditional Chinese medicine after myocardial cell injury. This article reviews the mechanism of ferroptosis and its relationship with myocardial cells， as well as traditional Chinese medicine monomers and formulas for treating CVDs through the ferroptosis pathway. The article focuses on the pathways and effects of traditional Chinese medicine treatment， so as to provide a reference for the treatment of CVDs with traditional Chinese medicine.

Role of Ferroptosis in Bone Homeostasis and Traditional Chinese Medicine Intervention： A Review / 中国实验方剂学杂志

Osteoporosis （OP） is a systemic metabolic bone disease characterized by bone microstructure degeneration and bone mass loss， which has a high prevalence and disability rate. Effective prevention and treatment of OP is a major difficulty in the medical community. The nature of OP is that multiple pathological factors lead to the imbalance of human bone homeostasis maintained by osteoblasts and osteoclasts. Ferroptosis is a non-apoptotic cell death pathway， and its fundamental cause is cell damage caused by iron accumulation and lipid peroxidation. Studies have shown that ferroptosis is involved in and affects the occurrence and development of OP， which leads to OP by mediating the imbalance of bone homeostasis. Ferroptosis is an adjustable form of programmed cell death. The intervention of ferroptosis can regulate the damage degree and death process of osteoblasts and osteoclasts， which is beneficial to maintain bone homeostasis， slow down the development process of OP， improve the clinical symptoms of patients， reduce the risk of disability， and improve their quality of life. However， there are few studies on ferroptosis in OP. Traditional Chinese medicine （TCM） is a medical treasure with unique characteristics and great application value in China. It has been widely used in China and has a long history. It has the multi-target and multi-pathway advantages in the treatment of OP， with high safety， few toxic and side effects， and low treatment cost， and has a significant effect in clinical application. The intervention of TCM in ferroptosis to regulate bone homeostasis may be a new direction for the prevention and treatment of OP in the future. This article summarized the regulatory mechanisms related to ferroptosis， discussed the role of ferroptosis in bone homeostasis， and reviewed the current status and progress of active ingredients in TCM compounds and monomers in the regulation of OP through ferroptosis， so as to provide a theoretical basis for the participation of TCM in the prevention and treatment of OP in the future.

Earthworm Protein Protects Vascular Endothelial Function in Spontaneously Hypertensive Rats via PI3K/Akt/Nrf2 Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo observe the effect of earthworm protein on the expression of phosphatidylinositol 3-kinase/protein kinase B/nuclear factor E2-related factor 2 （PI3K/Akt/Nrf2） pathway in the aorta of spontaneously hypertensive rats （SHR） and explore mechanism of earthworm protein in treating hypertensive vascular endothelial dysfunction （VED）. MethodTen 10-week-old Wistar Kyoto （WKY） rats and fifty SHR rats were selected for a week of adaptive feeding. WKY rats were selected as the normal group， and fifty SHR rats were randomized according to body weight into model， valsartan （8×10-3 g·kg-1·d-1）， and high-， medium-， and low-dose （0.2， 0.1， 0.05 g·kg-1·d-1， respectively） earthworm protein groups. The normal and model groups were administrated with equal volume of double distilled water by gavage. During the drug intervention period， the general situations of rats in each group were observed and their blood pressure was monitored at specific time points every other week before and after administration. After 8 weeks of drug intervention， enzyme-linked immunosorbent assay was employed to measure the levels of angiotensin-Ⅱ （Ang-Ⅱ） and endothelin-1 （ET-1） in the serum of rats in each group. The corresponding kits were used to determine the levels of nitric oxide （NO）， malondialdehyde （MDA）， glutathione peroxidase （GPX）， superoxide dismutase （SOD）， and ferrous ion （Fe2+）. Hematoxylin-eosin （HE） staining was employed to observe the changes in the intima of the aorta. Fluorescence quantitative polymerase chain reaction （Real-time PCR） was employed to measure the mRNA levels of PI3K， Akt， Nrf2， heme oxygenase-1 （HO-1）， and glutathione peroxidase 4 （GPX4） in the aortic tissue. Western blotting was used to determine the protein levels of p-PI3K （Tyr467/199）， PI3K， p-Akt （Ser473）， Akt， Nrf2， HO-1， and GPX4 in the thoracic aorta. ResultCompared with the normal group， the model group had decreased body mass， increased irritability， severe endothelial damage， elevated blood pressure and serum levels of Ang-Ⅱ， ET1， MDA， and Fe2+ （P<0.01）， lowered NO level （P<0.01）， and down-regulated mRNA and protein levels of p-PI3K （Tyr467/199）， PI3K， p-Akt （Ser473）， Akt， Nrf2， HO-1， and GPX4 in the aortic tissue （P<0.01）. Compared with the model group， drug intervention caused no significant change in the body mass， calmed the rats， alleviated the endothelial damage， lowered blood pressure and serum levels of Ang-Ⅱ， ET1， MDA， and Fe2+ （P<0.01）， elevated the NO level （P<0.05）， and up-regulated the mRNA and protein levels of p-PI3K （Tyr467/199）， PI3K， p-Akt （Ser473）， Akt， Nrf2， HO-1， and GPX4 （P<0.05）. ConclusionThe earthworm protein can exert antihypertensive effects by ameliorating VED in SHR. Specifically， it may regulate the PI3K/Akt/Nrf2 signaling pathway to inhibit oxidative stress and ferroptosis.

Inductores de ferroptosis para el tratamiento del cáncer

Introducción: La ferroptosis es un proceso no apoptótico de muerte celular regulada que depende de la presencia de iones hierro en el medio intracelular. Se caracterizada por la acumulación de especies reactivas de lípidos oxidados y radicales libres en las membranas celulares. Los inductores e inhibidores de este proceso inciden de manera circunstancial en él, con cuya respuesta celular se trabaja en función de elaborar modelos para el tratamiento del cáncer. Objetivo: Profundizar en el proceso de ferroptosis con un enfoque hacia los inductores e inhibidores, el establecimiento de modelos biofisicoquímicos y las estrategias terapéuticas para el tratamiento del cáncer. Métodos: Se realizó una revisión de los estudios más significativos sobre el tema, publicados en la Web of Science, PubMed, EBSCO, y Scopus. Resultados: Gracias al novedoso descubrimiento de la ferroptosis como impulsor de la muerte de células tumorales para tratar el cáncer, se han comenzado a desarrollar modelos teóricos que simulan el comportamiento de estas células y la complejidad en sistemas biológicos; que permiten encontrar procedimientos alternativos y menos invasivos contra esta y otras enfermedades. Conclusiones: Los inductores e inhibidores tienen una función primordial a la hora de predecir la influencia en la sensibilidad a la ferroptosis; por lo que se indagó en los mecanismos de funcionamiento de estos, que facilitará la forma de inducir en mayor o menor grado la muerte celular y disminuir la población de células cancerígenas.

Introduction: Ferroptosis is a non-apoptotic process of regulated cell death that depends on the presence of iron ions in the intracellular medium. It is characterized by the accumulation of reactive species of oxidized lipids and free radicals in cell membranes. The inducers and inhibitors of this process circumstantially affect it, whose cellular response is used to develop models for cancer treatment. Objective: To deepen the ferroptosis process focusing on inducers and inhibitors, the establishment of biophysiochemical models and therapeutic strategies for cancer treatment. Methods: A review was carried out of the most significant studies on the subject, published in the Web of Science, PubMed, EBSCO and Scopus. Results: Thanks to the novel discovery of ferroptosis as a conductor of tumor cell death to treat cancer, theoretical models have begun to be developed that simulate the behavior of these cells and the complexity in biological systems; that allow finding alternative and less invasive procedures against this and other diseases. Conclusions: Inductors and inhibitors have a primary role in predicting the influence on sensitivity to ferroptosis; therefore, the mechanisms of operation of these were investigated, which will facilitate the way to induce cell death to a greater or lesser degree and reduce the population of cancer cells.

Astragaloside IV alleviates stroke-triggered early brain injury by modulating neuroinflammation and ferroptosis via the Nrf2/HO-1 signaling pathway

Purpose: Stroke is an acute cerebrovascular disease. Astragaloside IV (AS-IV) is an active ingredient extracted from Astragalus membranaceus with an established therapeutic effect on central nervous system diseases. This study examined the neuroprotective properties and possible mechanisms of AS-IV in stroke-triggered early brain injury (EBI) in a rat transient middle cerebral artery occlusion (MCAO) model. Methods: The neurological scores and brain water content were analyzed. 2,3,5-triphenyl tetrazolium chloride (TTC) staining was utilized to determine the infarct volume, neuroinflammatory cytokine levels, and ferroptosis-related genes and proteins, and neuronal damage and molecular mechanisms were evaluated by terminal deoxynucleotidyl transferase dutp nickend labeling (TUNEL) staining, western blotting, and real-time polymerase chain reaction. Results: AS-IV administration decreased the infarct volume, brain edema, neurological deficits, and inflammatory cytokines TNF-α, interleukin-1ß (IL-1ß), IL-6, and NF-κB, increased the levels of SLC7A11 and glutathione peroxidase 4 (GPX4), decreased lipid reactive oxygen species (ROS) levels, and prevented neuronal ferroptosis. Meanwhile, AS-IV triggered the Nrf2/HO-1 signaling pathway and alleviated ferroptosis due to the induction of stroke. Conclusion: Hence, the findings of this research illustrate that AS-IV administration can improve delayed ischemic neurological deficits and decrease neuronal death by modulating nuroinflammation and ferroptosis via the Nrf2/HO-1 signaling pathway.

Boosting ferroptosis and microtubule inhibition for antitumor therapy via a carrier-free supermolecule nanoreactor / 药物分析学报

Traditional microtubule inhibitors fail to significantly enhance the effect of colorectal cancer;hence,new and efficient strategies are necessary.In this study,a supramolecular nanoreactor(DOC@TA-Fe3+)based on tannic acid(TA),iron ion(Fe3+),and docetaxel(DOC)with microtubule inhibition,reactive oxygen species(ROS)generation,and glutathione peroxidase 4(GPX4)inhibition,is prepared for ferroptosis/apoptosis treatment.After internalization by CT26 cells,the DOC@TA-Fe3+nanoreactor escapes from the lysosomes to release payloads.The subsequent Fe3+/Fe2+conversion mediated by TA reducibility can trigger the Fenton reaction to enhance the ROS concentration.Additionally,Fe3+can consume gluta-thione to repress the activity of GPX4 to induce ferroptosis.Meanwhile,the released DOC controls microtubule dynamics to activate the apoptosis pathway.The superior in vivo antitumor efficacy of DOC@TA-Fe3+nanoreactor in terms of tumor growth inhibition and improved survival is verified in CT26 tumor-bearing mouse model.Therefore,the nanoreactor can act as an effective apoptosis and ferroptosis inducer for application in colorectal cancer therapy.

A ferroptosis-related long non-coding RNA signature associated with prognosis in esophageal cancer / 中国医师进修杂志

Objective:To explore the prognostic value of ferroptosis-related long non-coding RNA (lncRNA) in esophageal cancer.Methods:Based on the Cancer Genome Atlas (TCGA), the predictive model was constructed based on the differentially expressed ferroptosis-related lncRNAs in esophageal cancer.Results:Seventeen differentially expressed ferroptosis-related lncRNAs (AC108673.2, LINC00942, CASC8, AP003696.1, LINC02154, AC092969.1, AC245100.5, AC011379.1, TMEM161B-AS1, LINC00092, LINC01977, AC107308.1, LINC00261, LINC00592, AP000553.2, HOXC-AS1, Z93403.1) related to the prognosis of esophageal cancer were identified. Kaplan-Meier analysis showed that the high-risk lncRNA feature was associated with a poor prognosis of esophageal cancer ( P<0.01). The area under the curve of the lncRNA feature was 0.861 at 1-year, 0.828 at 2-year, 0.764 at 3-year; and it showed superiority over conventional clinical pathology features in predicting the prognosis of esophageal cancer. In addition, there were significant differences in immune cells between the low-risk and high-risk groups. The immune checkpoints such as TNFSF 9, CD70 and TNFRSF 25 were also different expression between the two risk groups. Conclusions:Ferroptosis-related lncRNA signature can precisely predict the prognosis of esophageal cancer and serve as therapeutic targets for esophageal cancer.

The effect of nuclear factor erythroid 2 related factor 2-induced inhibition of ferroptosis on hyperoxia lung injury / 中华实用儿科临床杂志

Objective:To observe the expression changes of nuclear factor erythroid 2 related factor 2 (Nrf2) and glutathione peroxidase (GPX4) in human pulmonary microvascular endothelial cells (HPMEC) under different experimental conditions, and to explore the role of Nrf2 in inhibiting ferroptosis in the process of alleviating hyperoxic lung injury(HLI).Methods:Hyperoxic model was established by hyperoxia exposure.HPMEC were treated with blank control (control group), oxygen exposure at the concentration of 950 mL/L (hyperoxia group), oxygen exposure at the concentration of 950 mL/L+ 10 μmol/L Ferrostatin (ferroptosis inhibitor group) and oxygen exposure at the concentration of 950 mL/L + 10 μmol/L ML385 (Nrf2 inhibitor group). Cell viability at 24 h and 48 h was tested by the Cell Counting Kit-8 assay, and reactive oxygen species (ROS) levels were detected by a commercial ROS kit.The mRNA and protein levels of Nrf2 and GPX4 were detected by real-time quantitative polymerase chain reaction and Western blot, respectively.Differences were analyzed using the Student′s t-test for a two-group comparison or one-way ANOVA test among groups. Results:(1)Compared with the control group, significantly decreased viability and increased ROS levels were detected in hyperoxia group.Meanwhile, the mRNA (24 h: 0.750±0.010 vs.1.010±0.160, 48 h: 0.690±0.050 vs.1.000±0.070) and protein levels of GPX4 (24 h: 0.160±0.010 vs.0.290±0.010, 48 h: 0.190±0.010 vs.0.250±0.010) at 24 h and 48 h were significantly downregulated, while the mRNA (24 h: 1.740±0.050 vs.1.000±0.050, 48 h: 2.130±0.020 vs.1.000±0.030) and protein levels of Nrf2 (24 h: 0.840±0.010 vs.0.480±0.010, 48 h: 0.840±0.010 vs.0.550±0.030) at 24 h and 48 h were significantly upregulated in hyperoxia group than those of control group (all P<0.05). (2)Compared with the hyperoxia group, significantly increased viability and decreased ROS levels were detected in ferroptosis inhibitor group.Meanwhile, the mRNA (24 h: 1.520±0.110, 48 h: 1.880±0.050) and protein levels of GPX4 (24 h: 0.290±0.010, 48 h: 0.250±0.004) at 24 h and 48 h were significantly upregulated, while the mRNA (24 h: 0.780±0.040, 48 h: 0.760±0.030) and protein levels of Nrf2 (24 h: 0.480±0.010, 48 h: 0.540±0.020) at 24 h and 48 h were significantly downregulated in ferroptosis inhibitor group than those of hyperoxia group (all P<0.05). (3)Compared with the hyperoxia group, significantly decreased viability and increased ROS levels were detected in Nrf2 inhibitor group.Meanwhile, the mRNA (24 h: 0.600±0.030, 48 h: 0.590±0.003) and protein levels of GPX4 (24 h: 0.150±0.001, 48 h: 0.180±0.001) at 24 h and 48 h were significantly downregulated, while the mRNA level of Nrf2 was significantly upregulated at 24 h (3.360±0.130), but downregulated at 48 h (1.430±0.130) (all P<0.05). No significant difference was detected in the protein level of Nrf2 at 24 h and 48 h between hyperoxia group and Nrf2 inhibitor group ( P>0.05). Conclusions:Ferroptosis is involved in the development of HLI, and Nrf2 is able to alleviate hyperoxic lung injury by inhibiting ferroptosis.Therefore, inhibition of ferroptosis by Nrf2 may provide a new therapeutic target for HLI.

Effects of tetramethylpyrazine on the expressions of ferroptosis related molecules after spinal cord injury in rats / 国际中医中药杂志

Objective:To study the effects of tetramethylpyrazine on the expressions of ferroptosis related molecules after spinal cord injury; To explore the mechanism of tetramethylpyrazine promoting the repair of spinal cord injury (SCI).Methods:Totally 36 SD rats were divided into sham-operation group, model group and tetramethylpyrazine group according to random number table method, with 12 rats in each group. The rats in the sham-operation group underwent laminectomy without injury to the spinal cord. The SCI model was prepared in the other two groups. The rats in the tetramethylpyrazine group were intraperitoneally injected with tetramethylpyrazine of 80 mg/kg, and the rats in the sham-operation group and model group were intraperitoneally injected with the same volume of normal saline, once a day, continuous intervention for 28 days. One day before operation and 1, 3, 5, 7, 14, 21, 28 days after operation, BBB limb motor function score was used to evaluate the limb motor function of rats. Nissl staining was used to observe the morphology of neurons. Prussian staining was used to observe iron deposition. Assay kit was used to detect the contents of MDA and ROS in spinal cord tissue. Western blot was used to detect the protein expressions of xCT, GPX4 and ACSL4, and qPCR was used to detect the mRNA expressions of mRNA of xCT, GPX4 and ACSL4.Results:On the 14th, 21st and 28th days after operation, compared with the model group, the BBB score of tetramethylpyrazine group increased ( P<0.01); tetramethylpyrazine could significantly improve the morphology and structure of neurons and reduce the iron content in spinal cord tissue; compared with the model group, the contents of MDA and ROS in the spinal cord tissue of tetramethylpyrazine group decreased ( P<0.01); the levels of xCT and GPX4 mRNA and protein increased ( P<0.01), while the expression of ACSL4 mRNA and protein decreased ( P<0.01). Conclusion:Tetramethylpyrazine can regulate lipid peroxidation by regulating the expressions of ferroptosis related molecules, which is conducive to the recovery of limb motor function in rats with spinal cord injury.

Research progress of ferroptosis in colorectal cancer / 国际生物医学工程杂志

Colorectal cancer is the third leading cause of cancer death worldwide and is characterized by frequent genetic mutations. Current chemotherapy, radiation, and surgical treatment options face challenges such as cancer recurrence and drug resistance. Treatment of colorectal cancer is often achieved by promoting various forms of programmed cell death. Iron death has been found to be an iron-dependent and lipid peroxide-driven form of programmed cell death. Studies suggest that iron death is an effective therapeutic strategy for colorectal cancer. However, a deeper understanding of the mechanisms of iron death onset, propagation, and drug resistance in colorectal cancer is needed. In this review paper, the mechanisms of iron death and its drug resistance pathways in colorectal cancer formation, metabolism, and treatment were reviewed, and future research directions were prospected to improve the treatment options for colorectal cancer.

Research Progress on Role of Ferroptosis in Immunoresistance of Advanced Non-small Cell Lung Cancer / 肿瘤防治研究

Ferroptosis is a novel regulatory cell death characterized by iron dependence and mainly caused by the accumulation of lipid peroxides and reactive oxygen species in the cell. This process plays an important role in the development of many malignancies, and has been extensively studied in lung cancer, especially in antitumor therapy. In recent years, the role of ferroptosis in tumor immunotherapy has been gradually explored. Studies showed that targeting ferroptosis can improve the therapeutic efficacy of antitumor immunotherapy. In addition, immunotherapy and ferroptosis can work synergistically to enhance the effectiveness of antitumor therapy, suggesting a potential relationship between ferroptosis and immunotherapy and the possible reversal of immune drug resistance. This study aims to elucidate the characteristics of ferroptosis, and the role and potential clinical applications of ferroptosis in the antitumor immunotherapy of advanced non-small cell lung cancer. We also explore the role of some nanomaterials that target the onset of tumor ferroptosis in facilitating immunotherapy.

Plumbagin Induces Ferroptosis Through Nrf-2/Keap1 Signaling Pathway in Bladder Cancer Cells / 中国实验方剂学杂志

ObjectiveTo explore the mechanism of plumbagin as a novel ferroptosis inducer in bladder cancer inhibition. MethodBladder cancer T24 cells were used in this study. The effect of different concentrations of plumbagin （0.1， 1， 2， 3， 6， 12， 24， 48 μmol·L-1） on the viability of T24 cells was detected by cell counting kit-8 （CCK-8）. The effect of different concentrations of plumbagin （1.5， 3， 6 μmol·L-1） on the apoptosis of T24 cells was detected by annexin V-fluorescein isothiocyanate （Annexin V FITC）/PI apoptosis kit. Different inhibitors （ferroptosis inhibitor Fer-1， apoptosis inhibitor VAD， and necroptosis inhibitor Nec-1） were used in combination with plumbagin （6 μmol·L-1）. Reactive oxygen species （ROS） fluorescent probe （DCFH-DA）， malonaldehyde （MDA）， and glutathione （GSH） kits were used to detect the effects of different concentrations of plumbagin （1.5， 3， 6 μmol·L-1） on the level of ROS and the content of MDA and GSH in T24 cells， respectively. The effect of different concentrations of plumbagin （1.5， 3， 6 μmol·L-1） on peroxide levels in T24 cells was detected by C11-BODIPY fluorescent probe. Western blot was used to detect the effect of different concentrations of plumbagin （1.5， 3， 6 μmol·L-1） on the protein expression of solute carrier family 7 member 11 （SLC7A11）， glutathione peroxidase 4 （GPX4）， nuclear factor E2-related factor-2 （Nrf-2）， and Kelch-like ECH-associated protein 1 （Keap1）. ResultCompared with the blank group， plumbagin could inhibit the activity of T24 cells （P<0.05） with IC50 of 3.52 μmol·L-1. At the concentrations of 1.5， 3， 6 μmol·L-1， plumbagin significantly promoted the apoptosis of T24 cells （P<0.05） as compared with the blank group. Compared with the plumbagin group at 6 μmol·L-1， the ferroptosis inhibitor and apoptosis inhibitor groups could reverse the inhibitory effect of 6 μmol·L-1 plumbagin on the proliferation of T24 cells （P<0.05）. Compared with the blank group， the plumbagin groups at 1.5， 3， 6 μmol·L-1 showed increased content of ROS， MDA， and lipid peroxides in T24 cells， decreased GSH level， and reduced SLC7A11， GPX4， and Nrf-2/Keap1 （P<0.05）. Conclusionplumbagin can induce ferroptosis， and its mechanism is related to the Nrf-2/Keap1 signaling pathway.

Bioinformatics analysis of ferroptosis-related gene expression profile in primary open angle glaucoma / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the ferroptosis-related key genes in the progression of primary open angle glaucoma(POAG)through bioinformatics analysis, aiming to gain a deeper understanding of the biological mechanism of ferroptosis in POAG.METHODS: The GSE27276 dataset, derived from the trabecular meshwork, was obtained from the GEO database. It consisted of 19 trabecular meshwork tissue samples and 17 normal trabecular meshwork tissue samples. The ferroptosis-related genes were obtained from the FerrDb database. Then the GSE27276 dataset with the ferroptosis gene set was mapped, differentially expressed ferroptosis-related genes(DE-FRGs)were identified in POAG, and the correlation analysis was performed. Additionally, the gene ontology(GO)function and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways of DE-FRGs were further analyzed. This study utilized two machine learning algorithms, namely the LASSO regression model and the SVM-RFE model, to identify the ferroptosis-related key genes of POAG. The screening results from both models were intersected to identify the most significant genes. The clinical diagnostic performance of these genes was evaluated using the receiver operating characteristic curve(ROC); the gene set enrichment analysis(GSEA)and gene set variation analysis(GSVA)were conducted on the most significant genes; the expression levels of these genes were validated using the GSE2378 and GSE9944 datasets obtained from the optic nerve head.RESULTS: In comparison to normal trabecular meshwork tissue, a total of 396 ferroptosis genes exhibited differential expression in POAG trabecular meshwork tissue. Among these, 39 genes were up-regulated while 64 genes were down-regulated. Spearman correlation analysis revealed certain correlation between the up-regulated genes and the down-regulated genes. The GO function and KEGG pathway enrichment analysis revealed that the differential genes were primarily enriched in the oxidative stress response and ferroptosis pathways. A total of 18 DE-FRGs were identified as key genes using LASSO and SVM-RFE algorithms, which demonstrated a higher diagnostic value. GSEA and GSVA revealed a significant association between GDF15, MFN2, and OTUB1 genes with the glutathione metabolic pathway. Moreover, it was observed that MFN2 activated the glutathione metabolic pathway in the high expression group, while OTUB1 activated it in the low expression group. The cross-validation of GSE2378 and GSE9944 datasets revealed a significant increase in the expression level of CREB1 in optic nerve specimens compared to normal optic nerve specimens, and it was consistent with the expression observed in trabecular meshwork samples from the GSE27276 dataset.CONCLUSION: Based on bioinformatics analysis, a total of 396 DE-FRGs were identified in POAG. By constructing a machine screening model and cross-validation of external datasets, CREB1 is expected to be the best characteristic gene for potential diagnostic biomarker, and provide targets for further elucidating the molecular mechanism and the diagnosis of ferroptosis in POAG. However, further in vivo and in vitro validation is required to elucidate the biological mechanism of ferroptosis in POAG.

Role and prospect of ferroptosis in ischemia-reperfusion injury during organ transplantation / 器官移植

Ferroptosis is a newly-emerged pattern of programmed cell death discovered in recent years, which is defined as iron-dependent programmed necrosis mediated by lipid peroxidation damage. As a conservative procedure, ferroptosis plays a vital role in the development and diseases of multiple organisms including plants and animals. Since ferroptosis was first reported in 2012, growing interests have been diverted to the process of ferroptosis and its role in disease treatment. Ischemia-reperfusion injury is a common pathological process during organ transplantation, and ferroptosis is considered as one of the main patterns inducing ischemia-reperfusion injury. Consequently, the definition, regulatory mechanism and the mechanisms of ferroptosis in ischemia-reperfusion injury after kidney, liver, heart and lung transplantations were reviewed, aiming to provide theoretical basis for the prevention and treatment of ischemia-reperfusion injury in organ transplantation.

Exploring the Pathogenesis of T2DM based on the Correlation between “Qi-fire Imbalance” and Ferroptosis / 中医杂志

@#Ferroptosis is a novel iron-dependent mode of programmed cell death characterized by iron deposition and accumulation of lipid peroxidation. More and more studies have found that ferroptosis is closely related to the pathogenesis of type 2 diabetes mellitus （T2DM）. The yin-fire theory is an important part of LI Gao's spleen-stomach theory， and it is believed that qi-fire imblance and yin-fire internal generation is the main pathogenesis of T2DM. Abnormal iron metabolism may be an important prerequisite for T2DM yin-fire internal generation， while oxidative stress is the specific manifestation of T2DM qi-fire imbalance. Reactive oxygen species （ROS） is the end product of qi-fire imbalance， and lipid peroxide is the pathological products of T2DM yin-fire internal generation. This study intends to explore the pathological mechanism of qi-fire imbalance and yin-fire internal generation from the perspectives of iron metabolism， oxidative stress and lipid peroxidation， enriching the modern connotation of yin-fire theory， and benefiting traditional Chinese medicine to target against ferroptosis， and prevent and treat T2DM precisely.

EHHADH is a key gene in fatty acid metabolism pathways in hepatocellular carcinoma: a transcriptomic analysis / 南方医科大学学报

OBJECTIVE@#To explore the driving gene of hepatocellular carcinoma (HCC) occurrence and progression and its potential as new therapeutic target of HCC.@*METHODS@#The transcriptome and genomic data of 858 HCC tissues and 493 adjacent tissues were obtained from TCGA, GEO, and ICGC databases. Gene Set Enrichment Analysis (GSEA) identified EHHADH (encoding enoyl-CoA hydratase/L-3-hydroxyacyl-CoA dehydrogenase) as the hub gene in the significantly enriched differential pathways in HCC. The downregulation of EHHADH expression at the transcriptome level was found to correlate with TP53 mutation based on analysis of the TCGA- HCC dataset, and the mechanism by which TP53 mutation caused EHHADH downregulation was explored through correlation analysis. Analysis of the data from the Metascape database suggested that EHHADH was strongly correlated with the ferroptosis signaling pathway in HCC progression, and to verify this result, immunohistochemical staining was used to examine EHHADH expression in 30 HCC tissues and paired adjacent tissues.@*RESULTS@#All the 3 HCC datasets showed signficnatly lowered EHHADH expression in HCC tissues as compared with the adjacent tissues (P < 0.05) with a close correlation with the degree of hepatocyte de-differentiation (P < 0.01). The somatic landscape of HCC cohort in TCGA dataset showed that HCC patients had the highest genomic TP53 mutation rate. The transcriptomic level of PPARGC1A, the upstream gene of EHHADH, was significantly downregulated in HCC patients with TP53 mutation as compared with those without the mutation (P < 0.05), and was significantly correlated with EHHADH expression level. GO and KEGG enrichment analyses showed that EHHADH expression was significantly correlated with abnormal fatty acid metabolism in HCC. The immunohistochemical results showd that the expression level of EHHADH in HCC tissues was down-regulated, and its expression level was related to the degree of hepatocytes de-differentiation and the process of ferroptosis.@*CONCLUSION@#TP53 mutations may induce abnormal expression of PPARGC1A to cause downregulation of EHHADH expression in HCC. The low expression of EHHADH is closely associated with aggravation of de-differentiation and ferroptosis escape in HCC tissues, suggesting the potential of EHHADH as a therapeutic target for HCC.