A search for food extracts inhibiting ferroptosis using immortalized mouse embryonic fibroblasts derived from xCT knockout mice.

Depleting glutathione by xCT inhibition induces iron-dependent ferroptotic cell death, which is suppressed by lipophilic antioxidants. We screened food extracts with xCTKO-MEFs, identifying garlic extracts as particularly potent in inhibiting ferroptosis among the food extracts examined in this study. xCTKO-MEFs can serve as a convenient tool for identifying food extracts that are effective in inhibiting ferroptosis.

Inhibiting Erastin-Induced Ferroptotic Cell Death by Purine-Based Chelators.

Ferroptosis is a cell death event caused by increased lipid peroxidation leading to iron-dependent oxidative stress and is associated with a wide variety of diseases. In recent years, ferroptosis inhibition has emerged as a novel strategy to target different pathologies. Here, we report the synthesis of two purine derivatives, 1 and 2, for iron chelation strategy and evaluate their potency to inhibit erastin-induced ferroptosis. Both compounds showed efficient iron chelation in solution as well as in cellular environment. The crystal structure of the purine derivatives with iron demonstrated a 2 : 1 (ligand to metal center) stoichiometry for iron and purine derivative complexation. The synthesized compounds also decrease the reactive oxygen species concentration in cell cultures. Compound 2 showed better potency towards the prevention of ferroptotic cell death as compared to commercially available iron chelator in the erastin-induced ferroptosis cell culture model. Such purine analogues are potential functional scaffolds for the development of target molecules for ferroptosis inhibition.

Phenolic furanochromene hydrazone derivatives: Synthesis, antioxidant activity, ferroptosis inhibition, DNA cleavage and DNA molecular docking studies.

Twenty-four phenolic furanochromene hydrazone derivatives were designed and synthesized in order to evaluate structure-activity relationships in a series of antioxidant-related assays. The derivatives have varying substitution patterns on the phenol ring, with some compounds having one, two or three hydroxy groups, and others containing one hydroxy group in combination with methoxy, methyl, bromo, iodo and/or nitro groups. Antioxidant activity was determined using the DPPH free radical scavenging and CUPRAC assays. Compounds containing ortho-dihydroxy and para-dihydroxy patterns had the highest free radical scavenging activity, with IC50 values ranging from 5.0 to 28 µM. Similarly, derivatives with ortho-dihydroxy and para-dihydroxy patterns, together with a 4-hydroxy-3,5­dimethoxy pattern, displayed strong copper (II) ion reducing capacity, using Trolox as a standard. Trolox equivalent antioxidant capacity (TEAC) coefficients for these derivatives ranged from 1.75 to 3.97. As further evidence of antioxidant potential, greater than half of the derivatives reversed erastin-induced ferroptosis in HaCaT cells. In addition, twenty-three of the derivatives were effective at cleaving supercoiled plasmid DNA in the presence of copper (II) ions at 1 mM, with the 3,4­dihydroxy derivative showing cleavage to both the linear and open circular forms at 3.9 uM. The interaction of the phenolic furanochromene derivatives with DNA was confirmed by molecular docking studies, which revealed that all the derivatives bind favorably in the minor groove of DNA.

Ferroptosis-Inhibitory Difference between Chebulagic Acid and Chebulinic Acid Indicates Beneficial Role of HHDP.

The search for a safe and effective inhibitor of ferroptosis, a recently described cell death pathway, has attracted increasing interest from scientists. Two hydrolyzable tannins, chebulagic acid and chebulinic acid, were selected for the study. Their optimized conformations were calculated using computational chemistry at the B3LYP-D3(BJ)/6-31G and B3LYP-D3(BJ)/6-311 + G(d,p) levels. The results suggested that (1) chebulagic acid presented a chair conformation, while chebulinic acid presented a skew-boat conformation; (2) the formation of chebulagic acid requires 762.1729 kcal/mol more molecular energy than chebulinic acid; and (3) the 3,6-HHDP (hexahydroxydiphenoyl) moiety was shown to be in an (R)- absolute stereoconfiguration. Subsequently, the ferroptosis inhibition of both tannins was determined using a erastin-treated bone marrow-derived mesenchymal stem cells (bmMSCs) model and compared to that of ferrostatin-1 (Fer-1). The relative inhibitory levels decreased in the following order: Fer-1 > chebulagic acid > chebulinic acid, as also revealed by the in vitro antioxidant assays. The UHPLC-ESI-Q-TOF-MS analysis suggested that, when treated with 16-(2-(14-carboxytetradecyl)-2-ethyl-4,4-dimethyl-3-oxazolidinyloxy free radicals, Fer-1 generated dimeric products, whereas the two acids did not. In conclusion, two hydrolyzable tannins, chebulagic acid and chebulinic acid, can act as natural ferroptosis inhibitors. Their ferroptosis inhibition is mediated by regular antioxidant pathways (ROS scavenging and iron chelation), rather than the redox-based catalytic recycling pathway exhibited by Fer-1. Through antioxidant pathways, the HHDP moiety in chebulagic acid enables ferroptosis-inhibitory action of hydrolyzable tannins.

Beyond Mortality: Exploring the Influence of Plant Phenolics on Modulating Ferroptosis-A Systematic Review.

Ferroptosis is a recently discovered type of programmed cell death that is mechanistically different from other types of programmed cell death such as apoptosis, necroptosis, and autophagy. It is characterized by the accumulation of intracellular iron, overproduction of reactive oxygen species, depletion of glutathione, and extensive lipid peroxidation of lipids in the cell membrane. It was discovered that ferroptosis is interconnected with many diseases, such as neurodegenerative diseases, ischemia/reperfusion injury, cancer, and chronic kidney disease. Polyphenols, plant secondary metabolites known for many bioactivities, are being extensively researched in the context of their influence on ferroptosis which resulted in a great number of publications showing the need for a systematic review. In this review, an extensive literature search was performed. Databases (Scopus, Web of Science, PubMed, ScienceDirect, Springer) were searched in the time span from 2017 to November 2023, using the keyword "ferroptosis" alone and in combination with "flavonoid", "phenolic acid", "stilbene", "coumarin", "anthraquinone", and "chalcone"; after the selection of studies, we had 311 papers and 143 phenolic compounds. In total, 53 compounds showed the ability to induce ferroptosis, and 110 compounds were able to inhibit ferroptosis, and out of those compounds, 20 showed both abilities depending on the model system. The most researched compounds are shikonin, curcumin, quercetin, resveratrol, and baicalin. The most common modes of action are in the modulation of the Nrf2/GPX4 and Nrf2/HO-1 axis and the modulation of iron metabolism.

Development and Application of the CRISPR-dcas13d-eIF4G Translational Regulatory System to Inhibit Ferroptosis in Calcium Oxalate Crystal-Induced Kidney Injury.

The CRISPR-Cas system, initially for DNA-level gene editing and transcription regulation, has expanded to RNA targeting with the Cas13d family, notably the RfxCas13d. This advancement allows for mRNA targeting with high specificity, particularly after catalytic inactivation, broadening the exploration of translation regulation. This study introduces a CRISPR-dCas13d-eIF4G fusion module, combining dCas13d with the eIF4G translation regulatory element, enhancing target mRNA translation levels. This module, using specially designed sgRNAs, selectively boosts protein translation in targeted tissue cells without altering transcription, leading to notable protein expression upregulation. This system is applied to a kidney stone disease model, focusing on ferroptosis-linked GPX4 gene regulation. By targeting GPX4 with sgRNAs, its protein expression is upregulated in human renal cells and mouse kidney tissue, countering ferroptosis and resisting calcium oxalate-induced cell damage, hence mitigating stone formation. This study evidences the CRISPR-dCas13d-eIF4G system's efficacy in eukaryotic cells, presenting a novel protein translation research approach and potential kidney stone disease treatment advancements.

Liposome-trimethyl chitosan nanoparticles codeliver insulin and siVEGF to treat corneal alkali burns by inhibiting ferroptosis.

Alkali burns are potentially blinding corneal injuries. Due to the lack of available effective therapies, the prognosis is poor. Thus, effective treatment methods for corneal alkali burns are urgently needed. Codelivery nanoparticles (NPs) with characteristics such as high bioavailability and few side effects have been considered effective therapeutic agents for ocular diseases. In this study, we designed a new combination therapy using liposomes and trimethyl chitosan (TMC) for the codelivery of insulin (INS) and vascular endothelial growth factor small interfering RNA (siVEGF) to treat alkali-burned corneas. We describe the preparation and characterization of siVEGF-TMC-INS-liposome (siVEGF-TIL), drug release characteristics, intraocular tracing, pharmacodynamics, and biosafety. We found that siVEGF-TIL could inhibit oxidative stress, inflammation, and the expression of VEGF in vitro and effectively maintained corneal transparency, accelerated epithelialization, and inhibited corneal neovascularization (CNV) in vivo. Morever, we found that the therapeutic mechanism of siVEGF-TIL is possibly relevant to the inhibition of the ferroptosis signaling pathway by metabolomic analysis. In general, siVEGF-TIL NPs could be a safe and effective therapy for corneal alkali burn.

Can Polyphenols Inhibit Ferroptosis?

Polyphenols, a diverse group of naturally occurring molecules commonly found in higher plants, have been heavily investigated over the last two decades due to their potent biological activities-among which the most important are their antioxidant, antimicrobial, anticancer, anti-inflammatory and neuroprotective activities. A common route of polyphenol intake in humans is through the diet. Since they are subjected to excessive metabolism in vivo it has been questioned whether their much-proven in vitro bioactivity could be translated to in vivo systems. Ferroptosis is a newly introduced, iron-dependent, regulated mode of oxidative cell death, characterized by increased lipid peroxidation and the accumulation of toxic lipid peroxides, which are considered to be toxic reactive oxygen species. There is a growing body of evidence that ferroptosis is involved in the development of almost all chronic diseases. Thus, ferroptosis is considered a new therapeutic target for offsetting many diseases, and researchers are putting great expectations on this field of research and medicine. The aim of this review is to critically analyse the potential of polyphenols to modulate ferroptosis and whether they can be considered promising compounds for the alleviation of chronic conditions.

On the role of synthesized hydroxylated chalcones as dual functional amyloid-ß aggregation and ferroptosis inhibitors for potential treatment of Alzheimer's disease.

In addition to amyloid cascade hypothesis, ferroptosis - a recently identified cell death pathway associated with the accumulation of lipid hydroperoxides - was hypothesized as one of the main forms of cell death in Alzheimer's disease. Herein, a series of hydroxylated chalcones were designed and synthesized as dual-functional inhibitors to inhibit amyloid-ß peptide (Aß) aggregation as well as ferroptosis simultaneously. Thioflavin-T assay indicated trihydroxy chalcones inhibited Aß aggregation better. In human neuroblastoma SH-SY5Y cells, cytoprotective chalcones 14a-c with three hydroxyl substituents exhibited a significant neuroprotection against Aß1-42 aggregation induced toxicity. In addition, chalcones 14a-c were found to be good inhibitors of ferroptosis induced by either pharmacological inhibition of the hydroperoxide-detoxifying enzyme Gpx4 using (1S, 3R)-RSL4 or cystine/glutamate antiporter system Xc- inhibition by erastin through lipid peroxidation inhibition mechanism. Trihydroxy chalcone 14a was also able to completely subvert lipid peroxidation induced by Aß1-42 aggregation in SH-SY5Y cells indicating that they can reduce the neurotoxicity involved with oxidative stress. Compound 14a-c showed good ADMET properties and blood-brain barrier penetration in silico simulation software. From these data, a picture emerges wherein trihydroxy chalcones are potential candidates for the treatment of Alzheimer's disease by simultaneously inhibition of Aß1-42 aggregation and ferroptosis.