Ferroptosis: Yet Another Way to Die

Ferroptosis resists intracellular Vibrio splendidus AJ01 mediated by ferroportin in sea cucumber Apostichopus japonicus

Ferroptosis, a kind of programmed cell death, is characterized with iron-dependent lipid ROS buildup, which is considered as an important cellular immunity in resisting intracellular bacterial infection in mammalian macrophages. In this process, lipid ROS oxidizes the bacterial biofilm to inhibit intracellular bacteria. However, the function of ferroptosis in invertebrate remains unknown. In this study, the existence of ferroptosis in Apostichopus japonicus coelomocytes was confirmed, and its antibacterial mechanism was investigated. First, our results indicated that the expression of glutathione peroxidase (AjGPX4) was significantly inhibited by 0.21-fold (p < 0.01) after injecting A. japonicus with the ferroptosis inducer RSL3, and the contents of MDA (3.93-fold, p < 0.01), ferrous iron (1.40-fold, p < 0.01), and lipid ROS (3.10-fold, p < 0.01) were all significantly increased under this condition and simultaneously accompanied with mitochondrial contraction and disappearance of cristae, indicating the existence of ferroptosis in the coelomocytes of A. japonicus. Subsequently, the contents of ferrous iron (1.40-fold, p < 0.05), MDA (2.10-fold, p < 0.01), ROS (1.70-fold, p < 0.01), and lipid ROS (2.50-fold, p < 0.01) were all significantly increased, whereas the mitochondrial membrane potential and GSH/GSSG were markedly decreased by 0.68-fold (p < 0.05) and 0.69-fold (p < 0.01) under Vibrio splendidus (AJ01) infection. This process could be reversed by the iron-chelating agent deferoxamine mesylate, which indicated that AJ01 could induce coelomocytic ferroptosis. Moreover, the results demonstrated that the intracellular AJ01 load was clearly decreased to 0.49-fold (p < 0.05) and 0.06-fold (p < 0.01) after treating coelomocytes with RSL3 and ferrous iron, which indicated that enhanced ferroptosis could inhibit bacterial growth. Finally, subcellular localization demonstrated that ferrous iron efflux protein ferroportin (AjFPN) and intracellular AJ01 were co-localized in coelomocytes. After AjFPN interference (0.58-fold, p < 0.01), the signals of ferrous iron and lipid ROS levels in intracellular AJ01 were significantly reduced by 0.38-fold (p < 0.01) and 0.48-fold (p < 0.01), indicating that AjFPN was an important factor in the introduction of ferroptosis into intracellular bacteria. Overall, our findings indicated that ferroptosis could resist intracellular AJ01 infection via AjFPN. These findings provide a novel defense mechanism for aquatic animals against intracellular bacterial infection.

Research progress of ferroptosis and inflammatory bowel disease

Inflammatory bowel disease (IBD) is a non-specific chronic inflammatory disorder of the gastrointestinal tract, imposing significant burdens on both society and individuals. As a new type of regulated cell death (RCD), ferroptosis is different from classic RCDs such as apoptosis and necrosis in cell morphology, biochemistry and genetics. The main molecular mechanisms of ferroptosis include dysregulation of iron metabolism, impaired antioxidant capacity, mitochondrial dysfunction, accumulation of lipid-associated super-oxides, and membrane disruption. In recent years, increasing evidence has shown that ferroptosis is involved in the pathophysiology of inflammatory bowel disease. However, the exact roles and underlying molecular mechanisms have not been fully elucidated. This article reviews the mechanism of ferroptosis in the occurrence and development of inflammatory bowel disease, in order to provide new ideas for the pathophysiological research of inflammatory bowel disease. Additionally, we discuss potential strategies for the prevention and treatment of inflammatory bowel disease by targeting ferroptosis.

Understanding the Novel Approach of Nanoferroptosis for Cancer Therapy

As a new form of regulated cell death, ferroptosis has unraveled the unsolicited theory of intrinsic apoptosis resistance by cancer cells. The molecular mechanism of ferroptosis depends on the induction of oxidative stress through excessive reactive oxygen species accumulation and glutathione depletion to damage the structural integrity of cells. Due to their high loading and structural tunability, nanocarriers can escort the delivery of ferro-therapeutics to the desired site through enhanced permeation or retention effect or by active targeting. This review shed light on the necessity of iron in cancer cell growth and the fascinating features of ferroptosis in regulating the cell cycle and metastasis. Additionally, we discussed the effect of ferroptosis-mediated therapy using nanoplatforms and their chemical basis in overcoming the barriers to cancer therapy.

Ecophysiological responses of Phragmites australis populations to a tidal flat gradient in the Yangtze River Estuary, China

Phragmites australis is a prevalent species in the Chongming Dongtan wetland and is capable of thriving in various tidal flat environments, including high salinity habitats. P. australis population displays inconsistent ecological performances, highlighting the need to uncover their survival strategies and mechanisms in tidal flats with diverse soil salinities. Upon comparing functional traits of P. australis at multiple tidal flats (low, middle, and high) and their responses to soil physicochemical properties, this study aimed to clarify the salt-tolerant strategy of P. australis and the corresponding mechanisms. These results showed that leaf characteristics, such as specific leaf area and leaf dry matter content, demonstrated more robust stability to soil salinity than shoot height and dry weight. Furthermore, as salt stress intensified, the activities of superoxide dismutase (SOD), catalase (CAT) and peroxisome (POD) in P. australis leaves at low tidal flat exhibited an increased upward trend compared to those at other tidal flats. The molecular mechanism of salt tolerance in Phragmites australis across various habitats was investigated using transcriptome sequencing. Weighted correlation network analysis (WGCNA) combined with differentially expressed genes (DEGs) screened out 3 modules closely related to high salt tolerance and identified 105 core genes crucial for high salt tolerance. Further research was carried out on the few degraded populations at low tidal flat, and 25 core genes were identified by combining WGCNA and DEGs. A decrease in the activity of ferroptosis marker gonyautoxin-4 and an increase in the content of Fe3+ in the degenerated group were observed, indicating that ferroptosis might participate in degradation. Furthermore, correlation analysis indicated a possible regulatory network between salt tolerance and ferroptosis. In short, this study provided new insights into the salt tolerance mechanism of P. australis population along tidal flats.

Delineation and authentication of ferroptosis genes in ventilator-induced lung injury

BACKGROUND

Mechanical ventilation, a critical support strategy for individuals enduring severe respiratory failure and general anesthesia, paradoxically engenders ventilator-induced lung injury (VILI). Ferrostatin-1 mitigates lung injury via ferroptosis inhibition, yet the specific ferroptosis genes contributing significantly to VILI remain obscure.

METHODS

Leveraging the Gene Expression Omnibus database, we acquired VILI-associated datasets and identified differentially expressed genes (DEGs). To identify the hub genes, we constructed a protein-protein interaction network and used three parameters from CytoHubba. Consequently, we identified hub genes and ferroptosis genes as ferroptosis hub genes for VILI (VFHGs). We conducted enrichment analysis and established receiver operating characteristic (ROC) curves for VFHGs. Subsequently, to confirm the correctness of the VFHGs, control group mice and VILI mouse models, as well as external dataset validation, were established. For further research, a gene-miRNA network was established. Finally, the CIBERSORT algorithm was used to fill the gap in the immune infiltration changes in the lung during VILI.

RESULTS

We identified 64 DEGs and 4 VFHGs (Il6,Ptgs2,Hmox1 and Atf3) closely related to ferroptosis. ROC curves demonstrated the excellent diagnostic performance of VFHGs in VILI. PCR and external dataset validation of the VILI model demonstrated the accuracy of VFHGs. Subsequently, the gene-miRNA network was successfully established. Ultimately, an Immune cell infiltration analysis associated with VILI was generated.

CONCLUSIONS

The results emphasize the importance of 4 VFHGs and their involvement in ferroptosis in VILI, confirming their potential as diagnostic biomarkers for VILI.

Ferrostatin-1 alleviates ventilator-induced lung injury by inhibiting ferroptosis

Ventilator-induced lung injury (VILI) has become an increasingly common complication in the clinic concerning mechanical ventilation. Previous research showed that VILI is the result of a response to cascade inflammation; however, the inflammatory mechanism involved remains unclear. As a newly recognized form of cell death, ferroptosis can release damage-related molecules (DAMPs) to trigger and amplify the inflammatory response and is involved in several inflammatory diseases. The present study aimed to investigate a previously unrecognized role of ferroptosis in VILI. A mouse model of VILI and a model of cyclic stretching (CS)-induced lung epithelial cell injury were established. Mice and cells were pretreated with ferrostain-1, an inhibitor of ferroptosis. Lung tissue and cells were then harvested to determine lung injury, inflammatory responses, indicators and protein expression associated with ferroptosis. Compared to the control group, mice subjected to high tidal volumes (HTV) for 4 h showed more severe pulmonary edema and inflammation and the activation of ferroptosis. Ferrostain-1 significantly ameliorated histological injury and inflammation in the VILI mouse and alleviated CS-induced lung epithelial cell injury. Mechanistically, ferrostain-1 markedly limited the activation of ferroptosis and recovered functionality of the SLC7A11/GPX4 axis both in vitro and in vivo, thus demonstrating its potential as a novel therapeutic target for VILI.

Targeting ferroptosis as a cell death pathway in Melanoma: From molecular mechanisms to skin cancer treatment

Melanoma, the most aggressive form of human skin cancer, has been under investigation to reach the most efficient treatment. Surgical resection for early-diagnosed primary melanoma, targeted therapies, and immune checkpoint inhibitors for advanced/metastatic melanoma is the best clinical approach. Ferroptosis, a newly identified iron-dependent cell death pathway, which is morphologically and biochemically different from apoptosis and necrosis, has been reported to be involved in several cancers. Ferroptosis inducers could provide therapeutic options in case of resistance to conventional therapies for advanced/metastatic melanoma. Recently developed ferroptosis inducers, MEK and BRAF inhibitors, miRNAs such as miR-137 and miR-9, and novel strategies for targeting major histocompatibility complex (MHC) class II in melanoma can provide new opportunities for melanoma treatment. Combining ferroptosis inducers with targeted therapies or immune checkpoint inhibitors increases patient response rates. Here we review the mechanisms of ferroptosis and its environmental triggers. We also discuss the pathogenesis and current treatments of melanoma. Moreover, we aim to elucidate the relationship between ferroptosis and melanoma and ferroptosis implications to develop new therapeutic strategies against melanoma.

Transcriptome Analysis of Heat Shock Factor C2a Over-Expressing Wheat Roots Reveals Ferroptosis-like Cell Death in Heat Stress Recovery

Wheat (Triticum aestivum L.) growing areas in many regions of the world are subject to heat waves which are predicted to increase in frequency because of climate change. The engineering of crop plants can be a useful strategy to mitigate heat stress-caused yield losses. Previously, we have shown that heat shock factor subclass C (TaHsfC2a-B)-overexpression significantly increased the survival of heat-stressed wheat seedlings. Although previous studies have shown that the overexpression of Hsf genes enhanced the survival of plants under heat stress, the molecular mechanisms are largely unknown. To understand the underlying molecular mechanisms involved in this response, a comparative analysis of the root transcriptomes of untransformed control and TaHsfC2a-overexpressing wheat lines by RNA-sequencing have been performed. The results of RNA-sequencing indicated that the roots of TaHsfC2a-overexpressing wheat seedlings showed lower transcripts of hydrogen peroxide-producing peroxidases, which corresponds to the reduced accumulation of hydrogen peroxide along the roots. In addition, suites of genes from iron transport and nicotianamine-related gene ontology categories showed lower transcript abundance in the roots of TaHsfC2a-overexpressing wheat roots than in the untransformed control line following heat stress, which are in accordance with the reduction in iron accumulation in the roots of transgenic plants under heat stress. Overall, these results suggested the existence of ferroptosis-like cell death under heat stress in wheat roots, and that TaHsfC2a is a key player in this mechanism. To date, this is the first evidence to show that a Hsf gene plays a key role in ferroptosis under heat stress in plants. In future, the role of Hsf genes could be further studied on ferroptosis in plants to identify root-based marker genes to screen for heat-tolerant genotypes.

The ferroptosis in haemocytes of Pacific oyster Crassostrea gigas upon erastin treatment

Ferroptosis is an iron and oxidative dependent form of cell death usually mediated by redox related molecules in vertebrates. In the present study, a glutathione peroxidase 4 (GPX4) and a solute carrier family 7 member 11 (SLC7A11, xCT) homologues were identified from the oyster Crassostrea gigas (designed as CgGPX4 and CgxCT), which contained a GSHPx domain and an AA_permease domain, respectively. The mRNA transcripts of CgGPX4 and CgxCT were expressed in all the examined tissues, including gill, gonad, adductor muscle, labial palp, mantle, hepatopancreas and haemocytes, with the highest expression in haemocytes. After erastin treatment, the rate of cell malformation and cell death increased significantly in haemocytes, and the mitochondrial atrophy, crest loss and fracture were observed in haemocytes. While the amount of Fe²⁺ and Malondialdehyde (MDA) increased significantly, the mRNA expressions of CgGPX4, CgxCT and voltage-dependent anion channel 2 (CgVDAC2) in haemocytes decreased significantly after erastin treatment. These results indicated that erastin was able to induce the ferroptosis of oyster haemocytes.

Regulatory roles of copper metabolism and cuproptosis in human cancers

Copper is an essential micronutrient for human body and plays a vital role in various biological processes including cellular respiration and free radical detoxification. Generally, copper metabolism in the body is in a stable state, and there are specific mechanisms to regulate copper metabolism and maintain copper homeostasis. Dysregulation of copper metabolism may have a great connection with various types of diseases, such as Wilson disease causing copper overload and Menkes disease causing copper deficiency. Cancer presents high mortality rates in the world due to the unlimited proliferation potential, apoptosis escape and immune escape properties to induce organ failure. Copper is thought to have a great connection with cancer, such as elevated levels in cancer tissue and serum. Copper also affects tumor progression by affecting angiogenesis, metastasis and other processes. Notably, cuproptosis is a novel form of cell death that may provide novel targeting strategies for developing cancer therapy. Copper chelators and copper ionophores are two copper coordinating compounds for the treatment of cancer. This review will explore the relationship between copper metabolism and cancers, and clarify copper metabolism and cuproptosis for cancer targeted therapy.

Ferroptosis As a Mechanism for Health Effects of Essential Trace Elements and Potentially Toxic Trace Elements

Ferroptosis is a unique form of programmed cell death driven by iron-dependent phospholipid peroxidation that was proposed in recent years. It plays an important role in processes of various trace element-related diseases and is regulated by redox homeostasis and various cellular metabolic pathways (iron, amino acids, lipids, sugars), as well as disease-related signaling pathways. Some limited pioneering studies have demonstrated ferroptosis as a mechanism for the health effects of essential trace elements and potentially toxic trace elements, with crosstalk among them. The aim of this review is to bring together research articles and identify key direct and indirect evidence regarding essential trace elements (iron, selenium, zinc, copper, chromium, manganese) and potentially toxic trace elements (arsenic, aluminum, mercury) and their possible roles in ferroptosis. Our review may help determine future research priorities and opportunities.

Ferroptosis-Driven Nanotherapeutics to Reverse Drug Resistance in Tumor Microenvironment

Ferroptosis, characterized by iron-dependent lipid reactive oxygen species (ROS) accumulation, is non-apoptotic programmed cell death highly relevant to tumor development. It was found to manipulate oncogenes and resistant mutations of cancer cells via lipid metabolism pathways converging on phospholipid glutathione peroxidase (GPX4) that squanders lipid peroxides (L-OOH) to block the iron-mediated reactions of peroxides, thus rendering resistant cancer cells vulnerable to ferroptotic cell death. By accumulating ROS and lipid peroxidation (LPO) products to lethal levels in tumor microenvironment (TME), ferroptosis-driven nanotherapeutics show a superior ability of eradicating aggressive malignancies than traditional therapeutic modalities, especially for the drug-resistant tumors with high metastasis tendency. Moreover, Fenton reaction, inhibition of GPX-4, and exogenous regulation of LPO are three major therapeutic strategies to induce ferroptosis in cancer cells, which were generally applied in ferroptosis-driven nanotherapeutics. In this review, we elaborate current trends of ferroptosis-driven nanotherapeutics to reverse drug resistance of tumors in anticancer fields at the intersection of cancer biology, materials science, and chemistry. Finally, their challenges and perspectives toward feasible translational studies are spotlighted, which would ignite the hope of anti-resistant cancer treatment.

Engineered Nanomaterial Exposure Affects Organelle Genetic Material Replication in Arabidopsis thaliana

Mitochondria and chloroplasts not only are cellular energy sources but also have important regulatory and developmental roles in cell function. CeO₂, FeOx ENMs, ZnS, CdS QDs, and relative metal salts were utilized in Murashige-Skoog (MS) synthetic growth medium at different concentrations (80-500 mg L^-1) and times of exposures (0-20 days). Analysis of physiological and molecular response of A. thaliana chloroplasts and mitochondrion demonstrates that ENMs increase or decrease functionality and organelle genome replication. Exposure to nanoscale CeO₂ and FeOx causes an 81-105% increase in biomass, whereas ZnS and CdS QDs yielded neutral or a 59% decrease in growth, respectively. Differential effects between ENMs and their corresponding metal salts highlight nanoscale-specific response pathways, which include energy production and oxidative stress response. Differences may be ascribed to ENM and the metal salt dissolution rate and the toxicity of the metal ion, which suggests eventual biotransformation processes occurring within the plant. With regard to specific effects on plastid (pt) and mitochondrial (mt) DNA, CdS QD exposure triggered potential variations at the substoichiometric level in the two organellar genomes, while nanoscale FeOx and ZnS QDs caused a 1- to 3-fold increase in ptDNA and mtDNA copy numbers. Nanoparticle CeO₂ exposure did not affect ptDNA and mtDNA stoichiometry. These findings suggest that modification in stoichiometry is a potential morpho-functional adaptive response to ENM exposure, triggered by modifications of bioenergetic redox balance, which leads to reducing the photosynthesis or cellular respiration rate.

Ferroptosis-Specific Inhibitor Ferrostatin-1 Relieves H2O2-Induced Redox Imbalance in Primary Cardiomyocytes through the Nrf2/ARE Pathway

Objective

Ischemic heart disease (IHD) has always been the focus of attention of many researchers in cardiovascular disease, and its pathogenesis is also very complicated. Ferroptosis may be involved in the occurrence and development of IHD.

Methods

First, primary cardiomyocytes were treated with H₂O₂ to simulate the IHD in vitro model. After pretreatment with different concentrations of ferrostatin-1, cell survival rate was detected by MTT method, cell apoptosis was detected by TUNEL staining and flow cytometry, and the expression of oxidative stress, ferroptosis, and related molecules of Nrf2/ARE pathway was detected by Western blotting (WB) and quantitative real-time polymerase chain reaction (qRT-PCR).

Results

The mortality of primary cardiomyocytes in the H₂O₂ group was obviously increased. Ferrostatin-1 treatment can effectively inhibit cell death, improve antioxidant enzyme activity, inhibit the expression of ferroptosis-related molecules, and activate Nrf2/ARE pathway expression.

Conclusion

Ferroptosis-specific inhibitor ferrostatin-1 relieves H₂O₂-induced redox imbalance in primary cardiomyocytes through the Nrf2/ARE pathway, inhibits ferroptosis, and thereby slows cardiomyocyte death.

Ferroptosis in Non-Small Cell Lung Cancer: Progression and Therapeutic Potential on It

As a main subtype of lung cancer, the current situation of non-small cell lung cancer (NSCLC) remains severe worldwide with a 19% survival rate at 5 years. As the conventional therapy approaches, such as chemotherapy, radiotherapy, targeted therapy, and immunotherapy, gradually develop into therapy resistance, searching for a novel therapeutic strategy for NSCLC is urgent. Ferroptosis, an iron-dependent programmed necrosis, has now been widely considered as a key factor affecting the tumorigenesis and progression in various cancers. Focusing on its effect in NSCLC, in different situations, ferroptosis can be triggered or restrained. When ferroptosis was induced in NSCLC, it was available to inhibit the tumor progression both in vitro and in vivo. The dominating mechanism was due to a regulation of the classic ferroptosis-repressed GSH-dependent GPX4 signaling pathway instead of other fractional regulating signal axes that regulated ferroptosis via impacting on the ROS, cellular iron levels, etc. In terms of the prevention of ferroptosis in NSCLC, an GSH-independent mechanism was also discovered, interestingly exhibiting the same upstream as the GPX4 signaling. In addition, this review summarizes the progression of ferroptosis in NSCLC and elaborates their association and specific mechanisms through bioinformatics analysis with multiple experimental evidence from different cascades. Finally, this review also points out the possibility of ferroptosis working as a novel strategy for therapy resistance in NSCLC, emphasizing its therapeutic potential.

PIEZO1 Ion Channel Mediates Ionizing Radiation-Induced Pulmonary Endothelial Cell Ferroptosis via Ca2+/Calpain/VE-Cadherin Signaling

Pulmonary endothelial cell dysfunction plays an important role in ionizing radiation (IR)-induced lung injury. Whether pulmonary endothelial cell ferroptosis occurs after IR and what are the underlying mechanisms remain elusive. Here, we demonstrate that 15-Gy IR induced ferroptosis characterized by lethal accumulation of reactive oxygen species (ROS), lipid peroxidation, mitochondria shrinkage, and decreased glutathione peroxidase 4 (GPX4) and SLC7A11 expression in pulmonary endothelial cells. The phenomena could be mimicked by Yoda1, a specific activator of mechanosensitive calcium channel PIEZO1. PIEZO1 protein expression was upregulated by IR in vivo and in vitro. The increased PIEZO1 expression after IR was accompanied with increased calcium influx and increased calpain activity. The effects of radiation on lung endothelial cell ferroptosis was partly reversed by inhibition of PIEZO1 activity using the selective inhibitor GsMTx4 or inhibition of downstreaming Ca²⁺/calpain signaling using PD151746. Both IR and activation of PIEZO1 led to increased degradation of VE-cadherin, while PD151746 blocked these effects. VE-cadherin knockdown by specific siRNA causes ferroptosis-like phenomena with increased ROS and lipid peroxidation in the lung endothelial cells. Overexpression of VE-cadherin partly recused the ferroptosis caused by IR or PIEZO1 activation as supported by decreased ROS production, lipid peroxidation and mitochondria shrinkage compared to IR or PIEZO1 activation alone. In summary, our study reveals a previously unrecognized role of PIEZO1 in modulating ferroptosis, providing a new target for future mitigation of radiation-induced lung injury.

Ferroptosis, a New Insight Into Acute Lung Injury

Acute lung injury (ALI), a common and critical illness with high morbidity and mortality, is caused by multiple causes. It has been confirmed that oxidative stress plays an important role in the development of ALI. Ferroptosis, a newly discovered programmed cell death in 2012, is characterized by iron-dependent lipid peroxidation and involved in many diseases. To date, compelling evidence reveals the emerging role of ferroptosis in the pathophysiological process of ALI. Here, we review the role of ferroptosis in the pathogenesis of ALI and its therapeutic potential in ALI.

Isolation, purification, and characterization of antioxidant peptides from fresh mare's milk

In this study, the whey protein of fresh mare's milk was used as raw material. The antioxidant peptide liquid XMNDT was extracted from fresh mare's milk solution and purified. The peptide had a molecular weight of 1594.89 kDa and was mainly composed of VAPFPQPVVPYPQR. Antioxidant peptide XMNDT could inhibit the proliferation of A549 lung cancer cells in the G1 phase, accelerate cell apoptosis, increase the activity of SOD and the amount of GSH, and reduce the secretion of MDA. It also exhibited certain antioxidant capacity and free radical scavenging. These data can provide a basis for research on new antioxidant properties by reducing the inflammation caused by aging.

Emerging mechanisms and targeted therapy of ferroptosis in cancer

Ferroptosis is an iron- and lipid reactive oxygen species (ROS)-dependent form of programmed cell death that is distinct from other forms of regulatory cell death at the morphological, biological, and genetic levels. Emerging evidence suggests critical roles for ferroptosis in cell metabolism, the redox status, and various diseases, such as cancers, nervous system diseases, and ischemia-reperfusion injury, with ferroptosis-related proteins. Ferroptosis is inhibited in diverse cancer types and functions as a dynamic tumor suppressor in cancer development, indicating that the regulation of ferroptosis can be utilized as an interventional target for tumor treatment. Small molecules and nanomaterials that reprogram cancer cells to undergo ferroptosis are considered effective drugs for cancer therapy. Here, we systematically summarize the molecular basis of ferroptosis, the suppressive effect of ferroptosis on tumors, the effect of ferroptosis on cellular metabolism and the tumor microenvironment (TME), and ferroptosis-inducing agents for tumor therapeutics. An understanding of the latest progress in ferroptosis could provide references for proposing new potential targets for the treatment of cancers.

Induction of ferroptosis in human nasopharyngeal cancer cells by cucurbitacin B: molecular mechanism and therapeutic potential

Cucurbitacin B (CuB) is a widely available triterpenoid molecule that exhibits various biological activities. Previous studies on the anti-tumour mechanism of CuB have mostly focused on cell apoptosis, and research on the ferroptosis-inducing effect has rarely been reported. Herein, we first discovered the excellent cytotoxicity of CuB towards human nasopharyngeal carcinoma cells and elucidated its potential ferroptosis-inducing mechanisms. Morphology alterations of mitochondrial ultrastructure, as observed via transmission electron microscopy, showed that CuB-treated cells undergo ferroptosis. CuB caused intracellular accumulation of iron ions and depletion of glutathione. Detailed molecular mechanism investigation confirmed that CuB both induced widespread lipid peroxidation and downregulated the expression of GPX4, ultimately initiating a multipronged mechanism of ferroptosis. Furthermore, CuB exhibited anti-tumour effects in vitro by inhibiting cellular microtubule polymerization, arresting cell cycle and suppressing migration and invasion. Finally, CuB significantly inhibited tumour progression without causing obvious side effects in vivo. Altogether, our study highlighted the therapeutic potential of CuB as a ferroptosis-inducing agent for nasopharyngeal cancer, and it provided valuable insights for developing effective anti-tumour agents with novel molecular mechanisms derived from natural products.

Recent Development on Plant Aldehyde Dehydrogenase Enzymes and Their Functions in Plant Development and Stress Signaling

Abiotic and biotic stresses induce the formation of reactive oxygen species (ROS), which subsequently causes the excessive accumulation of aldehydes in cells. Stress-derived aldehydes are commonly designated as reactive electrophile species (RES) as a result of the presence of an electrophilic α, β-unsaturated carbonyl group. Aldehyde dehydrogenases (ALDHs) are NAD(P)⁺-dependent enzymes that metabolize a wide range of endogenous and exogenous aliphatic and aromatic aldehyde molecules by oxidizing them to their corresponding carboxylic acids. The ALDH enzymes are found in nearly all organisms, and plants contain fourteen ALDH protein families. In this review, we performed a critical analysis of the research reports over the last decade on plant ALDHs. Newly discovered roles for these enzymes in metabolism, signaling and development have been highlighted and discussed. We concluded with suggestions for future investigations to exploit the potential of these enzymes in biotechnology and to improve our current knowledge about these enzymes in gene signaling and plant development.

Mitochondria-targeted delivery and light controlled release of iron prodrug and CO to enhance cancer therapy by ferroptosis

Mitochondrial malfunction is considered to be a decisive signal of apoptosis.