Ferroptosis: a cell death connecting oxidative stress, inflammation and cardiovascular diseases

Ototoxicity of polystyrene nanoplastics in mice, HEI-OC1 cells and zebrafish

Polystyrene nanoplastics are a novel class of pollutants. They are easily absorbed by living organisms, and their potential toxicity has raised concerns. However, the impact of polystyrene nanoplastics on auditory organs remains unknown. Here, our results showed that polystyrene nanoplastics entered the cochlea of mice, HEI-OC1 cells, and lateral line hair cells of zebrafish, causing cellular injury and increasing apoptosis. Additionally, we found that exposure to polystyrene nanoplastics resulted in a significant elevation in the auditory brainstem response thresholds, a loss of auditory sensory hair cells, stereocilia degeneration and a decrease in expression of Claudin-5 and Occludin proteins at the blood-lymphatic barrier in mice. We also observed a significant decrease in the acoustic alarm response of zebrafish after exposure to polystyrene nanoplastics. Mechanistic analysis revealed that polystyrene nanoplastics induced up-regulation of the Nrf2/HO-1 pathway, increased levels of malondialdehyde, and decreased superoxide dismutase and catalase levels in cochlea and HEI-OC1 cells. Furthermore, we observed that the expression of ferroptosis-related indicators GPX4 and SLC7A11 decreased as well as increased expression of ACLS4 in cochlea and HEI-OC1 cells. This study also revealed that polystyrene nanoplastics exposure led to increased expression of the inflammatory factors TNF-α, IL-1β and COX2 in cochlea and HEI-OC1 cells. Further research found that the cell apoptosis, ferroptosis and inflammatory reactions induced by polystyrene nanoplastics in HEI-OC1 cells was reversed through the pretreatment with N-acetylcysteine, a reactive oxygen species inhibitor. Overall, our study first discovered and systematically revealed the ototoxicity of polystyrene nanoplastics and its underlying mechanism.

Ferroptosis Exists in Ischemia Reperfusion Injury after Cardiac Surgery with Cardiopulmonary Bypass

Ischemia-reperfusion (IR) injury commonly arises during cardiac surgery involving Cardiopulmonary Bypass (CPB), and it has relationship with ferroptosis in mice. However, the exact role of ferroptosis in the human cardiac damage caused by cardiac surgery remains unclear. Basic patient data and perioperative period information were collected, and clinic indicators related to cardiac function were detected to assess the extent of cardiac injury. Cardiac tissue samples were collected to determine histopathological changes, ultrastructure of mitochondrial and hallmarks of ferroptosis. 25 patients were involved in this study. In the present study, we observed a significant increase in the clinical indicator hs-cTnT, with levels rising more than 1393 ± 242 folds (P < 0.0001) following the cardiac surgery. Masson staining revealed a notable increase in fibrosis levels by 2.282 ± 0.259% (P = 0.0009). Furthermore, there was a significant elevation in lipid peroxidation, as evidenced by a 61.42 ± 17.33% increase in MDA (P = 0.0006). Additionally, we observed notable swelling, decreased mitochondrial crista, and even fragmented mitochondria. Notably, changes in the marker gene of ferroptosis were observed, with PTGS2 showing a 6.437 ± 0.81 folds increase (P < 0.0001). Furthermore, key regulators such as SLC7A11 and GPX4 proteins exhibited a reduction of 97.33 ± 25.78% (P = 0.0068) and 60.59 ± 14.93% (P = 0.0071), respectively, indicating the occurrence of ferroptosis following the surgery. Ferroptosis exists in myocardial IR injury caused by cardiac surgery with CPB, indicating that targeting ferroptosis could serve as a potential strategy for myocardial protection against CPB-induced IR injury. The trial has been registered in Chinese Clinical Trial Registry (ChiCTR, No. ChiCTR2200061995) on July 16th, 2022.

A Nutrient-Deficient Microenvironment Facilitates Ferroptosis Resistance via the FAM60A-PPAR Axis in Pancreatic Ductal Adenocarcinoma

Ferroptosis, a nonapoptotic form of cell death, is an emerging potential therapeutic target for various diseases, including cancer. However, the role of ferroptosis in pancreatic cancer remains poorly understood. Pancreatic ductal adenocarcinoma (PDAC) is characterized by a poor prognosis and chemotherapy resistance, attributed to its high Kirsten rats arcomaviral oncogene homolog mutation rate and severe nutritional deficits resulting from a dense stroma. Several studies have linked rat sarcoma (RAS) mutations to ferroptosis, suggesting that inducing ferroptosis may be an effective strategy against oncogenic RAS-bearing tumors. We investigated the role of Family With Sequence Similarity 60 Member A (FAM60A) in this study, a protein closely associated with a poor prognosis and highly expressed in PDAC and tumor tissue from KrasG12D/+;Trp53R172H/+; Pdx1-Cre mice, in regulating ferroptosis, tumor growth, and gemcitabine sensitivity in vitro and in vivo. Our results demonstrate that FAM60A regulates 3 essential metabolic enzymes, ACSL1/4 and GPX4, to protect PDAC cells from ferroptosis. Furthermore, we found that YY1 transcriptionally regulates FAM60A expression by promoting its transcription, and the Hippo-YY1 pathway is restricted in the low-amino-acid milieu in the context of nutrient deprivation, leading to downstream suppression of peroxisome proliferator-activated receptor and ACSL1/4 and activation of GPX4 pathways. Importantly, FAM60A knockdown sensitized PDAC cells to gemcitabine treatment. A new understanding of FAM60A transcriptional regulation pattern in PDAC and its dual function in ferroptosis reliever and chemotherapy resistance is provided by our study. Targeting FAM60A may therefore offer a promising therapeutic approach for PDAC by simultaneously addressing 2 major features of the disease (high RAS mutation rate and tumor microenvironment nutrient deficiency) and preventing tumor cell metabolic adaptation.

METTL3 regulates TFRC ubiquitination and ferroptosis through stabilizing NEDD4L mRNA to impact stroke

BACKGROUND

Stroke is a major medical problem, and novel therapeutic targets are urgently needed. This study investigates the protective role and potential mechanisms of the N6-methyladenosine (m6A) RNA methyltransferase METTL3 against cerebral injury resulting from insufficient cerebral blood flow.

METHODS

In this study, we constructed mouse MCAO models and HT-22 cell OGD/R models to mimic ischemic stroke-induced brain injury and neuronal damage. We generated NEDD4L knockout and METTL3 overexpression models and validated therapeutic effects using infarct volume, brain edema, and neurologic scoring. We performed qRT-PCR, western blotting, and co-immunoprecipitation to assess the influence of NEDD4L on ferroptosis markers and TFRC expression. We verified the effect of NEDD4L on TFRC ubiquitination by detecting half-life and ubiquitination. Finally, we validated the impact of METTL3 on NEDD4L mRNA stability and MCAO outcomes in both in vitro and in vivo experimental models.

RESULT

We find NEDD4L expression is downregulated in MCAO models. Overexpressing METTL3 inhibits the iron carrier protein TFRC by upregulating the E3 ubiquitin ligase NEDD4L, thereby alleviating oxidative damage and ferroptosis to protect the brain from ischemic injury. Mechanistic studies show METTL3 can methylate and stabilize NEDD4L mRNA, enhancing NEDD4L expression. As a downstream effector, NEDD4L ubiquitinates and degrades TFRC, reducing iron accumulation and neuronal ferroptosis.

CONCLUSION

In summary, we uncover the METTL3-NEDD4L-TFRC axis is critical for inhibiting post-ischemic brain injury. Enhancing this pathway may serve as an effective strategy for stroke therapy. This study lays the theoretical foundation for developing m6A-related therapies against ischemic brain damage.

Increased ferroptosis in leukocytes from preeclamptic women involving the long non-coding taurine upregulated gene 1 (TUG1)

BACKGROUND

Ferroptosis plays a key role in placental development and physiology, and abnormal ferroptosis has been implicated in trophoblast injury leading to preeclampsia (PE). We hypothesize that leukocytes isolated from PE exhibit increased ferroptosis and that extracellular vesicles contain long non-coding (lnc) RNA/mRNAs that modulate oxidative stress and iron toxicity in vascular endothelial cells.

METHODS

We measured the expression of key regulators of ferroptosis in leukocytes and extracellular vesicles as well as circulating biomarkers of iron homeostasis and oxidative stress in plasma from women with/without PE at different timepoints during pregnancy. For markers that were dysregulated, we assessed their temporal correlation with established markers of disease activity and marker of endothelial activation. For markers dysregulated in early pregnancy, we assessed their ability to predict the development of PE.

RESULTS

We found decreased lncRNA/mRNAs in leukocytes, but not extracellular vesicles, in PE that may modulate oxidative stress and iron toxicity. This decrease in anti-ferroptotic markers does not appear to be related to maternal disease activity or plasma oxidative stress status but rather to attenuated anti-inflammatory expression in these cells. Circulating ferritin was elevated in PE, supporting the hypothesis that PE represents a disbalance in iron homeostasis. Low lncRNA taurine upregulated gene 1 RNA levels in leukocytes at 22-24 weeks were strongly associated with the development of PE.

CONCLUSIONS

Our findings suggest that maternal leukocytes in PE show decreased anti-ferroptotic activity that correlates with anti-inflammatory expression. Moreover, some of these changes in ferroptotic activity appear to precede the development of PE.

Identification of differentially expressed genes associated with ferroptosis in Crohn's disease

Ferroptosis-related genes may play a critical regulatory role in the pathogenesis of Crohn's disease (CD). The purpose of the present study was to identify genes expressed in CD that are associated with ferroptosis, and to provide guidance in the diagnosis and therapy of CD. CD mRNA expression data were initially gathered from the Gene Expression Omnibus (GEO) database. GSE75214 and GSE102133 datasets were selected as the major targets and were analyzed for differentially expressed genes (DEGs). Subsequently, R software was used to analyze the common genes among the DEGs between CD and ferroptosis-related genes. Gene Ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genome pathway analysis were conducted to identify related pathways and functions. Protein-protein interaction (PPI) analysis was performed to identify target genes. The DSigDB website was used to predict potential target drugs for hub genes. Reverse transcription-quantitative (RT-q) PCR was employed to detect the expression of these ferroptosis-related genes in clinical samples obtained from healthy controls and patients with CD. According to the two GEO datasets, 13 ferroptosis DEGs (11 upregulated genes and two downregulated genes) were identified in CD with thresholds of P<0.05 and |log2 fold change|>1, and were selected for further analysis. PPI analysis indicated the mutual effects among these genes and filtered out five hub genes. The top 10 potential targeted drugs were selected. The qPCR results showed that the expression levels of three genes, namely, IL-6, prostaglandin-endoperoxide synthase 2 (PTGS2) and dual oxidase 2 (DUOX2), were different between CD samples and healthy samples. This result was consistent with the results obtained from the bioinformatics analysis. In conclusion, bioinformatics analysis identified a total of 13 ferroptosis-associated genes in CD. Further verification by qPCR showed that IL-6, PTGS2 and DUOX2 may affect the process of CD by regulating ferroptosis. These findings might provide new biomarkers, diagnostic and therapeutic markers for CD.

Understanding the mechanistic roles of microplastics combined with heavy metals in regulating ferroptosis: Adding new paradigms regarding the links with diseases

As a new type of pollutant, microplastics (MPs) commonly exist in today's ecosystems, causing damage to the ecological environment and the health of biological organisms, including human beings. MPs can function as carriers of heavy metals (HMs) to aggravate the enrichment of HMs in important organs of organisms, posing a great threat to health. Ferroptosis, a novel process for the regulation of nonapoptotic cell death, has been shown to be closely related to the occurrence and processes of MPs and HMs in diseases. In recent years, some HMs, such as cadmium (Cd), iron (Fe), arsenic (As) and copper (Cu), have been proven to induce ferroptosis. MPs can function as carriers of HMs to aggravate damage to the body. This damage involves oxidative stress, mitochondrial dysfunction, lipid peroxidation (LPO), inflammation, endoplasmic reticulum stress (ERS) and so on. Therefore, ferroptosis has great potential as a therapeutic target for diseases induced by MPs combined with HMs. This paper systematically reviews the potential effects and regulatory mechanisms of MPs and HMs in the process of ferroptosis, focusing on the mitochondrial damage, Fe accumulation, LPO, ERS and inflammation caused by MPs and HMs that affect the regulatory mechanism of ferroptosis, providing new insights for research on regulating drugs and for the development of ferroptosis-targeting therapy for Alzheimer's disease, Parkinson's disease, cancer and cardiovascular disease.

Apigenin-7-glucoside-loaded nanoparticle alleviates intestinal ischemia-reperfusion by ATF3/SLC7A11-mediated ferroptosis

Intestinal ischemia reperfusion injury (II/R injury) is a common and intractable pathophysiological process in critical patients, for which exploring new treatments and mechanisms is of great importance to improve treatment outcomes. Apigenin-7-O-Glucoside (AGL) is a sugar derivative of apigenin natural product with various pharmacological activities to protect against intestinal diseases. In this study, we synthesized two amphiphilic molecules, namely DTPA-N10-10 and mPEG-TK-DA, which can scavenge free radicals and reactive oxygen species (ROS). They were successfully encapsulated AGL through self-assembly, resulting in the formation of multi-site ROS scavenging nanoparticles called PDN@AGL. In vitro and in vivo experiments demonstrated that PDN@AGL could protect intestinal tissues by reducing lipid peroxidation, lowering ROS levels and inhibiting ferroptosis during II/R injury. Furthermore, our study revealed, for the first time, that the regulation of the ATF3/SLC7A11 pathway by PDN@AGL may play a crucial role in mitigating II/R injury. In conclusion, our study confirmed the beneficial effects of PDN@AGL in combating II/R injury through the ATF3/SLC7A11-mediated regulation of ferroptosis and oxidative stress. These findings lay the groundwork for the potential application of PDN@AGL in the treatment of II/R injury.

Electroacupuncture Reduces Inflammatory Bowel Disease in Obese Mice by Activating the Nrf2/HO-1 Signaling Pathways and Repairing the Intestinal Barrier

Background

Electroacupuncture (EA) is used to treat inflammatory bowel disease (IBD). Nevertheless, the precise mechanisms by which this approach safeguards against obesity-induced intestinal barrier damage has not been fully understood.

Objective

This study aimed to assess whether EA could ameliorate intestinal barrier damage that had been reversed in a mouse model of obesity induced by a high-fat diet (HFD) and whether this repair is correlated with ferroptosis and gut microbiota enhancement.

Methods

To assess the potential of EA to prevent obesity and restore the intestinal barrier, we divided in C57BL/6J mice into two groups; one was fed with HFD and another one with a normal diet. Samples of stool, blood, fat, and intestinal epithelium were then evaluated, along with body weight.

Results

Following EA, we observed a significant reduction in body weight, fat accumulation, and serum triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) levels; an increase was seen in high-density lipoprotein cholesterol (HDL-C) levels. EA also activated the Nrf2 signaling pathway; upregulated the expression of GPX4, FTH1, and SLC7A11; and downregulated the expression of TFR1. In addition, the administration of EA resulted in a notable modification of the gut microbiota composition, characterized by a decrease in the Firmicutes to Bacteroidetes ratio.

Conclusion

EA had beneficial effects on weight loss and showed potential ability to repair the intestinal barrier by activating the Nrf2 signaling pathway, inhibiting intestinal inflammation and ferroptosis, and regulating the intestinal microbiota to treat IBD caused by HFD-induced obesity.

Targeting ferroptosis and ferritinophagy: new targets for cardiovascular diseases

Cardiovascular diseases (CVDs) are a leading factor driving mortality worldwide. Iron, an essential trace mineral, is important in numerous biological processes, and its role in CVDs has raised broad discussion for decades. Iron-mediated cell death, namely ferroptosis, has attracted much attention due to its critical role in cardiomyocyte damage and CVDs. Furthermore, ferritinophagy is the upstream mechanism that induces ferroptosis, and is closely related to CVDs. This review aims to delineate the processes and mechanisms of ferroptosis and ferritinophagy, and the regulatory pathways and molecular targets involved in ferritinophagy, and to determine their roles in CVDs. Furthermore, we discuss the possibility of targeting ferritinophagy-induced ferroptosis modulators for treating CVDs. Collectively, this review offers some new insights into the pathology of CVDs and identifies possible therapeutic targets.

Programmed cell death in tumor immunity: mechanistic insights and clinical implications

Programmed cell death (PCD) is an evolutionarily conserved mechanism of cell suicide that is controlled by various signaling pathways. PCD plays an important role in a multitude of biological processes, such as cell turnover, development, tissue homeostasis and immunity. Some forms of PCD, including apoptosis, autophagy-dependent cell death, pyroptosis, ferroptosis and necroptosis, contribute to carcinogenesis and cancer development, and thus have attracted increasing attention in the field of oncology. Recently, increasing research-based evidence has demonstrated that PCD acts as a critical modulator of tumor immunity. PCD can affect the function of innate and adaptive immune cells, which leads to distinct immunological consequences, such as the priming of tumor-specific T cells, immunosuppression and immune evasion. Targeting PCD alone or in combination with conventional immunotherapy may provide new options to enhance the clinical efficacy of anticancer therapeutics. In this review, we introduce the characteristics and mechanisms of ubiquitous PCD pathways (e.g., apoptosis, autophagy-dependent cell death, pyroptosis and ferroptosis) and explore the complex interaction between these cell death mechanisms and tumor immunity based on currently available evidence. We also discuss the therapeutic potential of PCD-based approaches by outlining clinical trials targeting PCD in cancer treatment. Elucidating the immune-related effects of PCD on cancer pathogenesis will likely contribute to an improved understanding of oncoimmunology and allow PCD to be exploited for cancer treatment.

Inflammation in Metal-Induced Neurological Disorders and Neurodegenerative Diseases

Essential metals play critical roles in maintaining human health as they participate in various physiological activities. Nonetheless, both excessive accumulation and deficiency of these metals may result in neurotoxicity secondary to neuroinflammation and the activation of microglia and astrocytes. Activation of these cells can promote the release of pro-inflammatory cytokines. It is well known that neuroinflammation plays a critical role in metal-induced neurotoxicity as well as the development of neurological disorders, such as Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS). Initially seen as a defense mechanism, persistent inflammatory responses are now considered harmful. Astrocytes and microglia are key regulators of neuroinflammation in the central nervous system, and their excessive activation may induce sustained neuroinflammation. Therefore, in this review, we aim to emphasize the important role and molecular mechanisms underlying metal-induced neurotoxicity. Our objective is to raise the awareness on metal-induced neuroinflammation in neurological disorders. However, it is not only just neuroinflammation that different metals could induce; they can also cause harm to the nervous system through oxidative stress, apoptosis, and autophagy, to name a few. The primary pathophysiological mechanism by which these metals induce neurological disorders remains to be determined. In addition, given the various pathways through which individuals are exposed to metals, it is necessary to also consider the effects of co-exposure to multiple metals on neurological disorders.

Novel diagnostic biomarkers of oxidative stress, ferroptosis, immune infiltration characteristics and experimental validation in ischemic stroke

Ischemic stroke (IS) is a prominent type of cerebrovascular disease leading to death and disability in an aging society and is closely related to oxidative stress. Gene expression profiling (GSE222551) was derived from Gene Expression Omnibus (GEO), and 1934 oxidative stress (OS) genes were obtained from the GeneCards database. Subsequently, we identified 149 differentially expressed genes related to OS (DEOSGs). Finally, PTGS2, FOS, and RYR1 were identified as diagnostic markers of IS. Moreover, GSE16561 was used to validate the DEOSGs. Two diagnostic genes (PTGS2 and FOS) were significantly highly expressed, while RYR1 was significantly lowly expressed in the IS group. Remarkably, immune infiltration characteristics of these three genes were analyzed, and we found that PTGS2, FOS, and RYR1 were mainly correlated with Mast cells activated, Neutrophils, and Plasma cells, respectively. Next, we intersected three DEOSGs with the ferroptosis gene set, the findings revealed that only PTGS2 was a differentially expressed gene of ferroptosis. High PTGS2 expression levels in the infarcted cortex of middle cerebral artery occlusion (MCAO) rats were confirmed by immunofluorescence (IF), western blotting (WB), and Immunohistochemistry (IHC). Inhibition of PTGS2 clearly improved the neurological outcome of rats by decreasing infarct volume, neurological problems, and modified neurological severity scores following IS compared with the controls. The protective effect of silencing PTGS2 may be related to anti-oxidative stress and ferroptosis. In conclusion, this work may provide a new perspective for the research of IS, and further research based on PTGS2 may be a breakthrough.

Ferroptosis: a new antidepressant pharmacological mechanism

The incidence rate of depression, a mental disorder, is steadily increasing and has the potential to become a major global disability factor. Given the complex pathological mechanisms involved in depression, the use of conventional antidepressants may lead to severe complications due to their side effects. Hence, there is a critical need to explore the development of novel antidepressants. Ferroptosis, a newly recognized form of cell death, has been found to be closely linked to the onset of depression. Several studies have indicated that certain active ingredients can ameliorate depression by modulating the ferroptosis signaling pathway. Notably, traditional Chinese medicine (TCM) active ingredients and TCM prescriptions have demonstrated promising antidepressant effects in previous investigations owing to their unique advantages in antidepressant therapy. Building upon these findings, our objective was to review recent relevant research and provide new insights and directions for the development and application of innovative antidepressant strategies.

The study of the mechanism of non-coding RNA regulation of programmed cell death in diabetic cardiomyopathy

Diabetic cardiomyopathy (DCM) represents a distinct myocardial disorder elicited by diabetes mellitus, characterized by aberrations in myocardial function and structural integrity. This pathological condition predominantly manifests in individuals with diabetes who do not have concurrent coronary artery disease or hypertension. An escalating body of scientific evidence substantiates the pivotal role of programmed cell death (PCD)-encompassing apoptosis, autophagy, pyroptosis, ferroptosis, and necroptosis-in the pathogenic progression of DCM, thereby emerging as a prospective therapeutic target. Additionally, numerous non-coding RNAs (ncRNAs) have been empirically verified to modulate the biological processes underlying programmed cell death, consequently influencing the evolution of DCM. This review systematically encapsulates prevalent types of PCD manifest in DCM as well as nascent discoveries regarding the regulatory influence of ncRNAs on programmed cell death in the pathogenesis of DCM, with the aim of furnishing novel insights for the furtherance of research in PCD-associated disorders relevant to DCM.

Quercetin alleviates PM2.5-induced chronic lung injury in mice by targeting ferroptosis

Background

PM2.5 is a well-known harmful air pollutant that can lead to acute exacerbation and aggravation of respiratory diseases. Although ferroptosis is involves in the pathological process of pulmonary disease, the potential mechanism of ferroptosis in PM2.5-caused lung inflammation and fibrosis need to be further clarified. Quercetin is a phenolic compound that can inhibit ferroptosis in various diseases. Hence, this study explores the role of ferroptosis in lung injury induced by PM2.5 in order to further elucidate the beneficial effect of quercetin and its underlying mechanism.

Methods

C57BL/6J mice were treated with either saline or PM2.5 by intratracheal instillation 20 times (once every two days). Additionally, PM2.5-treated mice were supplemented with two doses of quercetin. Lung injury, lipid peroxidation, iron content and ferroptosis marker protein expression and the Nrf2 signaling pathway were evaluated. In vitro, cell experiments were applied to verify the mechanisms underlying the links between Nrf2 signaling pathway activation and ferroptosis as well as between ferroptosis and inflammation.

Results

In vivo, PM2.5 increased lung inflammation and caused lung fibrosis and increased lipid peroxidation contents, iron contents and ferroptosis markers in lung tissues; these effects were significantly reversed by quercetin. Additionally, quercetin upregulated the nuclear Nrf2 expression and downregulated Keap1 expression in lung tissues of PM2.5-exposed mice. Quercetin decreased lipid peroxidation products, iron contents and ferroptosis levels and increased the nuclear translocation of Nrf2 and the degradation of Keap1 in PM2.5-exposed BEAS-2B cells. Moreover, we found that quercetin and dimethyl fumarate markedly decreased lipid peroxidation production and ferroptosis by activating the Nrf2-Keap1 pathway in PM2.5-exposed cells. Furthermore, quercetin reduced inflammatory cytokines and TGF-β1 in PM2.5-exposed cells.

Conclusion

Our data suggested that Nrf2 is involved in ferroptosis in PM2.5-induced lung injury, and quercetin can alleviate these adverse effects via activating Nrf2-Keap1 signaling pathway.

Identification and validation of ferroptosis-related genes for diabetic retinopathy

Diabetic retinopathy (DR) is a leading cause of blindness, and ferroptosis may be an essential component of the pathological process of DR. In this study, we aimed to screen five hub genes (TLR4, CAV1, HMOX1, TP53, and IL-1B) using bioinformatics analysis and experimentally verify their expression and effects on ferroptosis and cell function. The online Gene Expression Omnibus microarray expression profiling datasets GSE60436 and GSE1025485 were selected for investigation. Ferroptosis-related genes that might be differentially expressed in DR were identified. Then, Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, and protein-protein interaction (PPI) network analyses were conducted to characterize the differentially-expressed ferroptosis-related genes. After tissue-specific analyses and external dataset validation of hub genes, the mRNA and protein levels of hub genes in retinal microvascular endothelial cells (HRMECs) symbiotic with high glucose were verified using real-time quantitative PCR (qRT-PCR) and immunocytochemistry (ICC). Finally, hub genes were knocked down using siRNA, and changes in ferroptosis and cell function were observed. Based on the differential expression analysis, 19 ferroptosis-related genes were identified. GO and KEGG enrichment analyses showed that ferroptosis-related genes were significantly enriched in reactive oxygen species metabolic processes, necrotic cell death, hypoxia responses, iron ion responses, positive regulation of cell migration involved in sprouting angiogenesis, NF-kappa B signaling pathway, ferroptosis, fluid shear stress, and atherosclerosis. Subsequently, PPI network analysis and critical module construction were used to identify five hub genes. Based on bioinformatics analysis of mRNA microarrays, qRT-PCR confirmed higher mRNA expression of five genes in the DR model, and immunocytochemistry confirmed their higher protein expression. Finally, siRNA interference was used to verify the effects of five genes on ferroptosis and cell function. Based on bioinformatics analysis, five potential genes related to ferroptosis were identified, and their upregulation may affect the onset or progression of DR. This study sheds new light on the pathogenesis of DR.

Circular RNA SLC8A1 triggers hippocampal neuronal ferroptosis by regulating FUS-mediated ATF3 mRNA stability in epilepsy

BACKGROUND

Epilepsy is a neurological disorder characterized by recurrent seizures and is often unresponsive to current treatment options. Ferroptosis, a recently defined iron-dependent regulated cell death, has been suggested as a potential therapeutic target for epilepsy due to its association with oxidative stress. Additionally, circRNA SLC8A1 (circSLC8A1) has been implicated in various neurological disorders and oxidative stress-related diseases but its involvement in epilepsy progression, particularly in relation to ferroptosis and oxidative stress, remains unclear.

METHODS

qRT-PCR, Western blot, IHC and ELISA assays were employed to validate the relative expression of targeted genes and proteins. The levels of ROS, iron, LOP and GSH were detected by commercial kits. RNA pull-down and RIP assays were employed to detect the interactions among circSLC8A1, FUS and ATF3. A rat epilepsy model was established for further in vivo confirmation.

RESULTS AND CONCLUSION

In this study, we investigated the potential involvement of circSLC8A1 in epilepsy progression and its connection to ferroptosis and oxidative stress. Our findings demonstrate that circSLC8A1 triggers neuronal ferroptosis by stabilizing ATF3 mRNA expression through recruitment with FUS. The induced neuronal ferroptosis contributes to epilepsy progression. These results enhance our understanding of epilepsy pathogenesis and may provide insights for the development of novel therapeutic strategies.

Fisetin ameliorates fibrotic kidney disease in mice via inhibiting ACSL4-mediated tubular ferroptosis

Kidney fibrosis is the hallmark of chronic kidney disease (CKD) progression, whereas no effective anti-fibrotic therapies exist. Recent evidence has shown that tubular ferroptosis contributes to the pathogenesis of CKD with persistent proinflammatory and profibrotic responses. We previously reported that natural flavonol fisetin alleviated septic acute kidney injury and protected against hyperuricemic nephropathy in mice. In this study, we investigated the therapeutic effects of fisetin against fibrotic kidney disease and the underlying mechanisms. We established adenine diet-induced and unilateral ureteral obstruction (UUO)-induced CKD models in adult male mice. The two types of mice were administered fisetin (50 or 100 mg·kg-1·d-1, i.g.) for 3 weeks or 7 days, respectively. At the end of the experiments, the mice were euthanized, and blood and kidneys were gathered for analyzes. We showed that fisetin administration significantly ameliorated tubular injury, inflammation, and tubulointerstitial fibrosis in the two types of CKD mice. In mouse renal tubular epithelial (TCMK-1) cells, treatment with fisetin (20 μM) significantly suppressed adenine- or TGF-β1-induced inflammatory responses and fibrogenesis, and improved cell viability. By quantitative real-time PCR analysis of ferroptosis-related genes, we demonstrated that fisetin treatment inhibited ferroptosis in the kidneys of CKD mice as well as in injured TCMK-1 cells, as evidenced by decreased ACSL4, COX2, and HMGB1, and increased GPX4. Fisetin treatment effectively restored ultrastructural abnormalities of mitochondrial morphology and restored the elevated iron, the reduced GSH and GSH/GSSG as well as the increased lipid peroxide MDA in the kidneys of CKD mice. Notably, abnormally high expression of the ferroptosis key marker ACSL4 was verified in the renal tubules of CKD patients (IgAN, MN, FSGS, LN, and DN) as well as adenine- or UUO-induced CKD mice, and in injured TCMK-1 cells. In adenine- and TGF-β1-treated TCMK-1 cells, ACSL4 knockdown inhibited tubular ferroptosis, while ACSL4 overexpression blocked the anti-ferroptotic effect of fisetin and reversed the cytoprotective, anti-inflammatory, and anti-fibrotic effects of fisetin. In summary, we reveal a novel aspect of the nephroprotective effect of fisetin, i.e. inhibiting ACSL4-mediated tubular ferroptosis against fibrotic kidney diseases.

Current insight on the mechanisms of programmed cell death in sepsis-induced myocardial dysfunction

Sepsis is a clinical syndrome characterized by a dysregulated host response to infection, leading to life-threatening organ dysfunction. It is a high-fatality condition associated with a complex interplay of immune and inflammatory responses that can cause severe harm to vital organs. Sepsis-induced myocardial injury (SIMI), as a severe complication of sepsis, significantly affects the prognosis of septic patients and shortens their survival time. For the sake of better administrating hospitalized patients with sepsis, it is necessary to understand the specific mechanisms of SIMI. To date, multiple studies have shown that programmed cell death (PCD) may play an essential role in myocardial injury in sepsis, offering new strategies and insights for the therapeutic aspects of SIMI. This review aims to elucidate the role of cardiomyocyte's programmed death in the pathophysiological mechanisms of SIMI, with a particular focus on the classical pathways, key molecules, and signaling transduction of PCD. It will explore the role of the cross-interaction between different patterns of PCD in SIMI, providing a new theoretical basis for multi-target treatments for SIMI.

Targeting epigenetic and posttranslational modifications regulating ferroptosis for the treatment of diseases

Ferroptosis, a unique modality of cell death with mechanistic and morphological differences from other cell death modes, plays a pivotal role in regulating tumorigenesis and offers a new opportunity for modulating anticancer drug resistance. Aberrant epigenetic modifications and posttranslational modifications (PTMs) promote anticancer drug resistance, cancer progression, and metastasis. Accumulating studies indicate that epigenetic modifications can transcriptionally and translationally determine cancer cell vulnerability to ferroptosis and that ferroptosis functions as a driver in nervous system diseases (NSDs), cardiovascular diseases (CVDs), liver diseases, lung diseases, and kidney diseases. In this review, we first summarize the core molecular mechanisms of ferroptosis. Then, the roles of epigenetic processes, including histone PTMs, DNA methylation, and noncoding RNA regulation and PTMs, such as phosphorylation, ubiquitination, SUMOylation, acetylation, methylation, and ADP-ribosylation, are concisely discussed. The roles of epigenetic modifications and PTMs in ferroptosis regulation in the genesis of diseases, including cancers, NSD, CVDs, liver diseases, lung diseases, and kidney diseases, as well as the application of epigenetic and PTM modulators in the therapy of these diseases, are then discussed in detail. Elucidating the mechanisms of ferroptosis regulation mediated by epigenetic modifications and PTMs in cancer and other diseases will facilitate the development of promising combination therapeutic regimens containing epigenetic or PTM-targeting agents and ferroptosis inducers that can be used to overcome chemotherapeutic resistance in cancer and could be used to prevent other diseases. In addition, these mechanisms highlight potential therapeutic approaches to overcome chemoresistance in cancer or halt the genesis of other diseases.

A human initial lymphatic chip reveals distinct mechanisms of primary lymphatic valve dysfunction in acute and chronic inflammation

Interstitial fluid uptake and retention by lymphatic vessels (LVs) play a role in maintaining interstitial fluid homeostasis. While it is well-established that intraluminal lymphatic valves in the collecting LVs prevent fluid backflow (secondary lymphatic valves), a separate valve system in the initial LVs that only permits interstitial fluid influx into the LVs, preventing fluid leakage back to the interstitium (primary lymphatic valves), remains incompletely understood. Although lymphatic dysfunction is commonly observed in inflammation and autoimmune diseases, how the primary lymphatic valves are affected by acute and chronic inflammation has scarcely been explored and even less so using in vitro lymphatic models. Here, we developed a human initial lymphatic vessel chip where interstitial fluid pressure and luminal fluid pressure are controlled to examine primary lymph valve function. In normal conditions, lymphatic drainage (fluid uptake) and permeability (fluid leakage) in engineered LVs were maintained high and low, respectively, which was consistent with our understanding of healthy primary lymph valves. Next, we examined the effects of acute and chronic inflammation. Under the acute inflammation condition with a TNF-α treatment (2 hours), degradation of fibrillin and impeded lymphatic drainage were observed, which were reversed by treatment with anti-inflammatory dexamethasone. Surprisingly, the chronic inflammation condition (repeated TNF-α treatments during 48 hours) deposited fibrillin to compensate for the fibrillin loss, showing no change in lymphatic drainage. Instead, the chronic inflammation condition led to cell death and disruption of lymphatic endothelial cell-cell junctions, increasing lymphatic permeability and fluid leakage. Our human lymphatic model shows two distinct mechanisms by which primary lymphatic valve dysfunction occurs in acute and chronic inflammation.

β-aminoisobutyrics acid, a metabolite of BCAA, activates the AMPK/Nrf-2 pathway to prevent ferroptosis and ameliorates lung ischemia-reperfusion injury

BACKGROUND

Lung ischemia-reperfusion (I/R) injury is a serious clinical problem without effective treatment. Enhancing branched-chain amino acids (BCAA) metabolism can protect against cardiac I/R injury, which may be related to bioactive molecules generated by BCAA metabolites. L-β-aminoisobutyric acid (L-BAIBA), a metabolite of BCAA, has multi-organ protective effects, but whether it protects against lung I/R injury is unclear.

METHODS

To assess the protective effect of L-BAIBA against lung I/R injury, an animal model was generated by clamping the hilum of the left lung, followed by releasing the clamp in C57BL/6 mice. Mice with lung I/R injury were pre-treated or post-treated with L-BAIBA (150 mg/kg/day), given by gavage or intraperitoneal injection. Lung injury was assessed by measuring lung edema and analyzing blood gases. Inflammation was assessed by measuring proinflammatory cytokines in bronchoalveolar lavage fluid (BALF), and neutrophil infiltration of the lung was measured by myeloperoxidase activity. Molecular biological methods, including western blot and immunofluorescence, were used to detect potential signaling mechanisms in A549 and BEAS-2B cells.

RESULTS

We found that L-BAIBA can protect the lung from I/R injury by inhibiting ferroptosis, which depends on the up-regulation of the expressions of GPX4 and SLC7A11 in C57BL/6 mice. Additionally, we demonstrated that the Nrf-2 signaling pathway is key to the inhibitory effect of L-BAIBA on ferroptosis in A549 and BEAS-2B cells. L-BAIBA can induce the nuclear translocation of Nrf-2. Interfering with the expression of Nrf-2 eliminated the protective effect of L-BAIBA on ferroptosis. A screening of potential signaling pathways revealed that L-BAIBA can increase the phosphorylation of AMPK, and compound C can block the Nrf-2 nuclear translocation induced by L-BAIBA. The presence of compound C also blocked the protective effects of L-BAIBA on lung I/R injury in C57BL/6 mice.

CONCLUSIONS

Our study showed that L-BAIBA protects against lung I/R injury via the AMPK/Nrf-2 signaling pathway, which could be a therapeutic target.

Natural compounds efficacy in complicated diabetes: A new twist impacting ferroptosis

Ferroptosis, as a way of cell death, participates in the body's normal physiological and pathological regulation. Recent studies have shown that ferroptosis may damage glucose-stimulated islets β Insulin secretion and programmed cell death of T2DM target organs are involved in the pathogenesis of T2DM and its complications. Targeting suppression of ferroptosis with specific inhibitors may provide new therapeutic opportunities for previously untreated T2DM and its target organs. Current studies suggest that natural bioactive compounds, which are abundantly available in drugs, foods, and medicinal plants for the treatment of T2DM and its target organs, have recently received significant attention for their various biological activities and minimal toxicity, and that many natural compounds appear to have a significant role in the regulation of ferroptosis in T2DM and its target organs. Therefore, this review summarized the potential treatment strategies of natural compounds as ferroptosis inhibitors to treat T2DM and its complications, providing potential lead compounds and natural phytochemical molecular nuclei for future drug research and development to intervene in ferroptosis in T2DM.

Deeper insight into ferroptosis: association with Alzheimer's, Parkinson's disease, and brain tumors and their possible treatment by nanomaterials induced ferroptosis

Ferroptosis is an emerging and novel type of iron-dependent programmed cell death which is mainly caused by the excessive deposition of free intracellular iron in the brain cells. This deposited free iron exerts a ferroptosis pathway, resulting in lipid peroxidation (LiPr). There are mainly three ferroptosis pathways viz. iron metabolism-mediated cysteine/glutamate, and LiPr-mediated. Iron is required by the brain as a redox metal for several physiological activities. Due to the iron homeostasis balance disruption, the brain gets adversely affected which further causes neurodegenerative diseases (NDDs) like Parkinson's and Alzheimer's disease, strokes, and brain tumors like glioblastoma (GBS), and glioma. Nanotechnology has played an important role in the prevention and treatment of these NDDs. A synergistic effect of nanomaterials and ferroptosis could prove to be an effective and efficient approach in the field of nanomedicine. In the current review, the authors have highlighted all the latest research in the field of ferroptosis, specifically emphasizing on the role of major molecular key players and various mechanisms involved in the ferroptosis pathway. Moreover, here the authors have also addressed the correlation of ferroptosis with the pathophysiology of NDDs and theragnostic effect of ferroptosis and nanomaterials for the prevention and treatment of NDDs.

What matters in aging is signaling for responsiveness

Biological responsiveness refers to the capacity of living organisms to adapt to changes in both their internal and external environments through physiological and behavioral mechanisms. One of the prominent aspects of aging is the decline in this responsiveness, which can lead to a deterioration in the processes required for maintenance, survival, and growth. The vital link between physiological responsiveness and the essential life processes lies within the signaling systems. To devise effective strategies for controlling the aging process, a comprehensive reevaluation of this connecting loop is imperative. This review aims to explore the impact of aging on signaling systems responsible for responsiveness and introduce a novel perspective on intervening in the aging process by restoring the compromised responsiveness. These innovative mechanistic approaches for modulating altered responsiveness hold the potential to illuminate the development of action plans aimed at controlling the aging process and treating age-related disorders.

Restoring the infected powerhouse: Mitochondrial quality control in sepsis

Sepsis is a dysregulated host response to an infection, characterized by organ failure. The pathophysiology is complex and incompletely understood, but mitochondria appear to play a key role in the cascade of events that culminate in multiple organ failure and potentially death. In shaping immune responses, mitochondria fulfil dual roles: they not only supply energy and metabolic intermediates crucial for immune cell activation and function but also influence inflammatory and cell death pathways. Importantly, mitochondrial dysfunction has a dual impact, compromising both immune system efficiency and the metabolic stability of end organs. Dysfunctional mitochondria contribute to the development of a hyperinflammatory state and loss of cellular homeostasis, resulting in poor clinical outcomes. Already in early sepsis, signs of mitochondrial dysfunction are apparent and consequently, strategies to optimize mitochondrial function in sepsis should not only prevent the occurrence of mitochondrial dysfunction, but also cover the repair of the sustained mitochondrial damage. Here, we discuss mitochondrial quality control (mtQC) in the pathogenesis of sepsis and exemplify how mtQC could serve as therapeutic target to overcome mitochondrial dysfunction. Hence, replacing or repairing dysfunctional mitochondria may contribute to the recovery of organ function in sepsis. Mitochondrial biogenesis is a process that results in the formation of new mitochondria and is critical for maintaining a pool of healthy mitochondria. However, exacerbated biogenesis during early sepsis can result in accumulation of structurally aberrant mitochondria that fail to restore bioenergetics, produce excess reactive oxygen species (ROS) and exacerbate the disease course. Conversely, enhancing mitophagy can protect against organ damage by limiting the release of mitochondrial-derived damage-associated molecules (DAMPs). Furthermore, promoting mitophagy may facilitate the growth of healthy mitochondria by blocking the replication of damaged mitochondria and allow for post sepsis organ recovery through enabling mitophagy-coupled biogenesis. The remaining healthy mitochondria may provide an undamaged scaffold to reproduce functional mitochondria. However, the kinetics of mtQC in sepsis, specifically mitophagy, and the optimal timing for intervention remain poorly understood. This review emphasizes the importance of integrating mitophagy induction with mtQC mechanisms to prevent undesired effects associated with solely the induction of mitochondrial biogenesis.

Association between exposure to mixture of heavy metals and hyperlipidemia risk among U.S. adults: A cross-sectional study

Previous studies have suggested that exposure to heavy metals might increase the risk of hyperlipidemia. However, limited research has investigated the association between exposure to mixture of heavy metals and hyperlipidemia risk. To explore the independent and combined effects of heavy metal exposure on hyperlipidemia risk, this study involved 3293 participants from the National Health and Nutrition Examination Survey (NHANES), including 2327 with hyperlipidemia and the remaining without. In the individual metal analysis, the logistic regression model confirmed the positive effects of barium (Ba), cadmium (Cd), mercury (Hg), Lead (Pb), and uranium (U) on hyperlipidemia risk, Ba, Cd, Hg and Pb were further validated in restricted cubic splines (RCS) regression model and identified as positive linear relationships. In the metal mixture analysis, weighted quantile sum (WQS) regression, Bayesian kernel machine regression (BKMR), and quantile-based g computation (qgcomp) models consistently revealed a positive correlation between exposure to metal mixture and hyperlipidemia risk, with Ba, Cd, Hg, Pb, and U having significant positive driving roles in the overall effects. These associations were more prominent in young/middle-aged individuals. Moreover, the BKMR model uncovered some interactions between specific heavy metals. In conclusion, this study offers new evidence supporting the link between combined exposure to multiple heavy metals and hyperlipidemia risk, but considering the limitations of this study, further prospective research is required.

Oxidative stress drives vascular smooth muscle cell damage in acute Stanford type A aortic dissection through HIF-1α/HO-1 mediated ferroptosis

Background

Acute Stanford type A aortic dissection (ATAAD) is characterized by intimal tearing and false lumen formation containing large amounts of erythrocytes with heme. Heme oxygenase 1 (HO-1) is the key enzyme to degrade heme for iron accumulation and further ferroptosis. The current study aimed at investigating the role of HO-1 in the dissection progression of ATAAD.

Methods

Bioinformatic analyses and experimental validation were performed to reveal ferroptosis and HO-1 expression in ATAAD. Human aortic vascular smooth muscle cell (HA-VSMC) was used to explore underlying molecular mechanisms and the role of HO-1 overexpression in ATAAD.

Results

Ferroptosis was identified as a critical manner of regulated cell death in ATAAD. HO-1 was screened as a key signature of ferroptosis in ATAAD, which was closely associated with oxidative stress. Single cell/nucleus transcriptomic analysis and histological staining revealed that HO-1 and HIF-1α were upregulated in vascular smooth muscle cell (VSMC) of ATAAD. Further in vitro experiments showed that H2O2-induced oxidative stress increased VSMC ferroptosis with the overexpression of HO-1, which could be suppressed by HIF-1α inhibitor PX-478. HIF-1α could transcriptionally regulate the expression of HO-1 through binding to its promoter region. Pharmacological inhibition of HO-1 by zinc protoporphyrin (ZnPP) did not reduce H2O2-induced HA-VSMC damage without heme co-incubation. However, H2O2-induced HA-VSMC damage was worsened when heme was added into the medium, and ZnPP could reduce HA-VSMC damage in this condition.

Conclusion

HO-1 is a key signature of VSMC ferroptosis in ATAAD. HIF-1α/HO-1 mediated ferroptosis might participate in oxidative stress induced VSMC damage.

Ferrostatin-1 attenuates hypoxic-ischemic brain damage in neonatal rats by inhibiting ferroptosis

Background

Hypoxic-ischemic brain damage (HIBD) is a type of brain damage that is caused by perinatal asphyxia and serious damages the central nervous system. At present, there is no effective drug for the treatment of this disease. Besides, the pathogenesis of HIBD remains elusive. While studies have shown that ferroptosis plays an important role in HIBD, its role and mechanism in HIBD are yet to be fully understood.

Methods

The HIBD model of neonatal rats was established using the Rice-Vannucci method. A complete medium of PC12 cells was adjusted to a low-sugar medium, and the oxygen-glucose deprivation model was established after continuous hypoxia for 12 h. Laser Doppler blood flow imaging was used to detect the blood flow intensity after modeling. 2,3,5-triphenyl tetrazolium chloride staining was employed to detect ischemic cerebral infarction in rat brain tissue, and hematoxylin and eosin staining and transmission electron microscopy were used to observe brain injury and mitochondrial damage. Immunofluorescence was applied to monitor the expression of GFAP. Real-time quantitative polymerase chain reaction, western blot, and immunofluorescence were utilized to detect the expression of messenger RNA and protein. The level of reactive oxygen species (ROS) in cells was detected using the ROS detection kit.

Results

The results showed that ferrostatin-1 (Fer-1) significantly alleviated the brain injury caused by hypoxia and ischemia. Fer-1 significantly increased the expression of SLC3A2, SLC7A11, ACSL3, GSS, and GPX4 (P<0.05) and dramatically decreased the expressions of GFAP, ACSL4, TFRC, FHC, FLC, 4-HNE, HIF-1α, and ROS (P<0.05).

Conclusions

Fer-1 inhibits ferroptosis and alleviates HIBD by potentially targeting the GPX4/ACSL3/ACSL4 axis; however, its specific mechanism warrants further exploration.

Integrated Analysis of Ferroptosis and Immunity-Related Genes Associated with Diabetic Kidney Disease

Purpose

Diabetic kidney disease (DKD) is the leading cause of chronic kidney disease (CKD) worldwide. Elucidation of the molecular mechanisms underlying ferroptosis and immunity in DKD could aid the development of potentially effective therapeutics. This study aimed to perform an integrated analysis of ferroptosis and immune-related differentially expressed mRNAs (DEGs) in DKD.

Materials and Methods

Gene expression profiles of samples obtained from patients with DKD and controls were downloaded from the Gene Expression Omnibus (GEO) database. The potential differentially expressed genes (DEGs) were screened using R software, and ferroptosis immune-related differentially expressed genes (FIRDEGs) were extracted from the DEGs. We performed functional enrichment analyses, and constructed protein-protein interaction (PPI) networks, transcription factor (TFs)-gene networks, and gene-drug networks to explore their potential biological functions. Correlation analysis and receiver operating characteristic curves were used for evaluating the FIRDEGs. We used the CIBERSORT algorithm to examine the composition of immune cells and determine the relationship between FIRDEG signatures and immune cells. Finally, the RNA expression of six FIRDEGs was validated in animal kidney samples using RT-PCR.

Results

We identified 80 FIRDEGs and performed their functional analyses. We identified six hub genes (Ccl5, Il18, Cybb, Fcgr2b, Myd88, and Ccr2) using PPI networks and predicted potential TF gene networks and gene-drug pairs. Immune cells, including M2 macrophages, resting mast cells, and gamma-delta T cells, were altered in DKD; the FIRDEGs (Fcgr2b, Cybb, Ccr2, and Ccl5) were closely correlated with the infiltration abundance of M2 macrophages and gamma-delta T cells. Finally, the hub genes were verified in mouse kidney samples.

Conclusion

We identified six hub FIRDEGs (Ccl5, Il18, Cybb, Fcgr2b, Myd88, and Ccr2) in DKD, and predicted the potential transcription factor gene networks and possible treatment targets for future research.

A novel UVA-associated circUBE2I mediates ferroptosis in HaCaT cells

Alternative splicing of precursor messenger RNA (pre-mRNA), including linear splicing and back splicing, produces multiple isoforms that lead to diverse cell fates in response to stimuli including ultraviolet radiation (UVR). Although UVR-induced linear gene splicing has been extensively studied in skin cells, the UVR-induced gene back-splicing events that lead to the production of circular RNAs (circRNAs) have not been thoroughly investigated. The present study used circRNA transcriptome sequencing to screen the differentially expressed circRNAs in human keratinocytes (HaCaT) after UVA irradiation. A total of 312 differentially expressed circRNAs were found in HaCaT cells post-UVR. Among the UVA-induced differentially expressed circRNAs, circUBE2I-a novel circRNA formed by exons 2-6 of the UBE2I gene-was the most significantly upregulated circRNA. RT-qPCR assay further confirmed the increase of circUBE2I level in HaCaT cells after UVA irradiation or H2 O2 treatment. RNase R digestion experiment revealed the stability of circUBE2I. Overexpression of circUBE2I in keratinocytes induced ferroptosis after UVA or H2 O2 , preventable by the ferroptosis inhibitor ferrostatin-1. Our study provides new insights into the role of circular RNAs in UVA-induced skin cell damage and suggests that circUBE2I could be a therapeutic target in UVR-aroused ferroptosis in skin cells.

Ferrous Ion Alleviates Lipid Deposition and Inflammatory Responses Caused by a High Cottonseed Meal Diet by Modulating Hepatic Iron Transport Homeostasis and Controlling Ferroptosis in Juvenile Ctenopharyngodon idellus

To investigate the mechanisms through which ferrous ion (Fe2+) addition improves the utilization of a cottonseed meal (CSM) diet, two experimental diets with equal nitrogen and energy content (low-cottonseed meal (LCM) and high-cottonseed meal (HCM) diets, respectively) containing 16.31% and 38.46% CSM were prepared. Additionally, the HCM diet was supplemented with graded levels of FeSO4·7H2O to establish two different Fe2+ supplementation groups (HCM + 0.2%Fe2+ and HCM + 0.4%Fe2+). Juvenile Ctenopharyngodon idellus (grass carps) (5.0 ± 0.5 g) were fed one of these four diets (HCM, LCM, HCM + 0.2%Fe2+ and HCM + 0.4%Fe2+ diets) for eight weeks. Our findings revealed that the HCM diet significantly increased lipid peroxide (LPO) concentration and the expression of lipogenic genes, e.g., sterol regulatory element binding transcription factor 1 (srebp1) and stearoyl-CoA desaturase (scd), leading to excessive lipid droplet deposition in the liver (p < 0.05). However, these effects were significantly reduced in the HCM + 0.2%Fe2+ and HCM + 0.4%Fe2+ groups (p < 0.05). Plasma high-density lipoprotein (HDL) concentration was also significantly lower in the HCM and HCM + 0.2%Fe2+ groups compared to the LCM group (p < 0.05), whereas low-density lipoprotein (LDL) concentration was significantly higher in the HCM + 0.2%Fe2+ and HCM + 0.4%Fe2+ groups than in the LCM group (p < 0.05). Furthermore, the plasma levels of liver functional indices, including alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and glucose (GLU), were significantly lower in the HCM + 0.4%Fe2+ group (p < 0.05). Regarding the expression of genes related to iron transport regulation, transferrin 2 (tfr2) expression in the HCM group and Fe2+ supplementation groups were significantly suppressed compared to the LCM group (p < 0.05). The addition of 0.4% Fe2+ in the HCM diet activated hepcidin expression and suppressed ferroportin-1 (fpn1) expression (p < 0.05). Compared to the LCM group, the expression of genes associated with ferroptosis and inflammation, including acyl-CoA synthetase long-chain family member 4b (acsl4b), lysophosphatidylcholine acyltransferase 3 (lpcat3), cyclooxygenase (cox), interleukin 1β (il-1β), and nuclear factor kappa b (nfκb), were significantly increased in the HCM group (p < 0.05), whereas Fe2+ supplementation in the HCM diet significantly inhibited their expression (p < 0.05) and significantly suppressed lipoxygenase (lox) expression (p < 0.05). Compared with the HCM group without Fe2+ supplementation, Fe2+ supplementation in the HCM diet significantly upregulated the expression of genes associated with ferroptosis, such as heat shock protein beta-associated protein1 (hspbap1), glutamate cysteine ligase (gcl), and glutathione peroxidase 4a (gpx4a) (p < 0.05), and significantly decreased the expression of the inflammation-related genes interleukin 15/10 (il-15/il-10) (p < 0.05). In conclusion, FeSO4·7H2O supplementation in the HCM diet maintained iron transport and homeostasis in the liver of juvenile grass carps, thus reducing the occurrence of ferroptosis and alleviating hepatic lipid deposition and inflammatory responses caused by high dietary CSM contents.

Neutrophils extracellular traps and ferroptosis in diabetic wounds

Wound healing is an extremely complex process involving multiple levels of cells and tissues. It is mainly completed through four stages: haemostasis, inflammation, proliferation, and remodelling. When any one of these stages is impaired, it may lead to delayed healing or even transformation into chronic refractory wounds. Diabetes is a kind of common metabolic disease that affects approximately 500 million people worldwide, 25% of whom develop skin ulcers that break down repeatedly and are difficult to heal, making it a growing public health problem. Neutrophils extracellular traps and ferroptosis are new types of programmed cell death identified in recent years and have been found to interact with diabetic wounds. In this paper, the normal wound healing and interfering factors of the diabetic refractory wound were outlined. The mechanism of two kinds of programmed cell death was also described, and the interaction mechanism between different types of programmed cell death and diabetic refractory wounds was discussed.

Oxidized Low-Density Lipoprotein (Ox-LDL)-Triggered Double-Lock Probe for Spatiotemporal Lipoprotein Oxidation and Atherosclerotic Plaque Imaging

Low-density lipoprotein (LDL), especially oxidative modified LDL (Ox-LDL), is the key risk factor for plaque accumulation and the development of cardiovascular disease. Herein, a highly specific Ox-LDL-triggered fluorogenic-colorimetric probe Pro-P1 is developed for visualizing the oxidation and aggregation progress of lipoproteins and plaque. A series of green fluorescent protein chromophores with modified donor-acceptor structures, containing carbazole as an electron donor and various substituents including pyridine-vinyl (P1), phenol-vinyl (P2), N, N-dimethylaniline-vinyl (P3), and thiophene-vinyl (P4), have been synthesized and evaluated. Emission spectroscopy and theoretical calculations of P1-P4 indicate that P1 shows enhanced green fluorescence (λem = 560 nm) by inhibiting its twisted intramolecular charge transfer in the presence of Ox-LDL. This feature allows the selection of P1 as a sensitive probe to directly visualize ferroptosis and Cu2+ -mediated LDL oxidative aggregation via in situ formation of fluorophore-bound Ox-LDL in living cells. The red-emissive probe Pro-P1 (λem = 660 nm) is prepared via borate protection of P1, which can be cleaved into P1 under high expression of HOCl and Ox-LDL condition at the lesion site, resulting in enhanced green emission. The plaque area and size with clear boundaries can be delineated by colorimetric fluorescence imaging and fluorescence lifetime imaging with precise differentiation.

Inhibition of SIRT6 aggravates p53-mediated ferroptosis in acute lung injury in mice

Although studies have shown that protein 53 (p53)-mediated ferroptosis is involved in acute lung injury (ALI), the mechanism of its regulation remains unclear. The protective effects of Sirtuin 6 (SIRT6), a histone deacetylase, have been demonstrated in multiple diseases; however, further studies are needed to elucidate the role of SIRT6 in ALI. In the present study, we hypothesize that SIRT6 protects against lipopolysaccharide (LPS)-induced ALI by regulating p53-mediated ferroptosis. We observed that the inhibition of ferroptosis prevented LPS-induced ALI. The knockout of p53 blocked LPS-induced ferroptosis and ALI, suggesting that p53 facilitated ALI by promoting ferroptosis. In addition, the inhibition of SIRT6 aggravated LPS-induced ferroptosis and ALI, while the depression of ferroptosis blocked the exacerbation of lung injury induced by SIRT6 inhibition. The results suggest that SIRT6 protects against ALI by regulating ferroptosis. Furthermore, the inhibition of SIRT6 reinforced the p53 acetylation and the deletion of p53 rescued the exacerbation of ferroptosis induced by SIRT6 inhibition. The findings indicate that SIRT6 regulates the acetylation of p53 and prevents p53-mediated ferroptosis. In conclusion, our results indicate that SIRT6 protects against LPS-induced ALI by regulating p53-mediated ferroptosis, thereby demonstrating that SIRT6 holds great promise as a therapeutic target for ALI.

Oxidative Stress and Potential Antioxidant Therapies in Vitiligo: A Narrative Review

Vitiligo is a chronic skin disorder characterised by the loss of melanocytes and subsequent skin depigmentation. Although many theories have been proposed in the literature, none alone explains the pathogenesis of vitiligo. Oxidative stress has been identified as a potential factor in the pathogenesis of vitiligo. A growing body of evidence suggests that antioxidant therapies may offer a promising approach to managing this condition. This review summarises the potential mechanisms of oxidative stress and the types of melanocyte death in vitiligo. We also provide a brief overview of the most commonly studied antioxidants. Melanocytes in vitiligo are thought to be damaged by an accumulation of reactive oxygen species to destroy the structural and functional integrity of their DNA, lipids, and proteins. Various causes, including exogenous and endogenous stress factors, an imbalance between prooxidants and antioxidants, disruption of antioxidant pathways, and gene polymorphisms, lead to the overproduction of reactive oxygen species. Although necroptosis, pyroptosis, ferroptosis, and oxeiptosis are newer types of cell death that may contribute to the pathophysiology of vitiligo, apoptosis remains the most studied cell death mechanism in vitiligo. According to studies, vitamin E helps to treat lipid peroxidation of the skin caused by psoralen ultra-violet A treatment. In addition, Polypodium leucotomos increased the efficacy of psoralen ultra-violet A or narrow-band ultraviolet B therapy. Our review provides valuable insights into the potential role of oxidative stress in pathogenesis and antioxidant-based supporting therapies in treating vitiligo, offering a promising avenue for further research and the development of effective treatment strategies.

Role of dysregulated ferroptosis‑related genes in cardiomyocyte ischemia‑reperfusion injury: Experimental verification and bioinformatics analysis

Acute myocardial infarction is a life-threatening condition with high mortality and complication rates. Although myocardial reperfusion can preserve ischemic myocardial tissue, it frequently exacerbates tissue injury, a phenomenon known as ischemia-reperfusion injury (IRI). However, the underlying pathological mechanisms of IRI remain to be completely understood. Ferroptosis is a novel type of regulated cell death that is associated with various pathological conditions, including angiocardiopathy. The purpose of this article was to elucidate the possible mechanistic role of ferroptosis in IRI through bioinformatics analysis and experimental validation. Healthy and IRI heart samples were screened for differentially expressed ferroptosis-related genes and functional enrichment analysis was performed to determine the potential crosstalk and pathways involved. A protein-protein interaction network was established for IRI, and 10 hub genes that regulate ferroptosis, including HIF1A, EGFR, HMOX1, and ATF3 were identified. In vitro, an anoxia/reoxygenation (A/R) injury model was established using H9c2 cardiomyoblasts to validate the bioinformatics analysis results, and extensive ferroptosis was detected. A total of 4 key hub genes and 3 key miRNAs were also validated. It was found that IRI was related to the aberrant infiltration of immune cells and the small-molecule drugs that may protect against IRI by preventing ferroptosis were identified. These results provide novel insights into the role of ferroptosis in IRI, which can help identify novel therapeutic targets.

Ferroptosis in the post-transplantation inflammatory response

Transplantation is a life-saving therapy for patients with end-stage organ disease. Successful outcomes after transplantation require mitigation of the post-transplant inflammatory response, limiting alloreactivity, and prevention of organ rejection. Traditional immunosuppressive regimens aim to dampen the adaptive immune response; however, recent studies have shown the feasibility and efficacy of targeting the innate immune response. Necroinflammation initiated by donor organ cell death is implicated as a critical mediator of primary graft dysfunction, acute rejection, and chronic rejection. Ferroptosis is a form of regulated cell death that triggers post-transplantation inflammation and drives the activation of both innate and adaptive immune cells. There is a growing acceptance of the clinical relevance of ferroptosis to solid organ transplantation. Modulating ferroptosis may be a potentially promising strategy to reduce complications after organ transplantation.

Salidroside inhibits renal ischemia/reperfusion injury‑induced ferroptosis by the PI3K/AKT signaling pathway

Renal ischemia/reperfusion injury (RIRI) represents the principal factor underlying acute kidney injury (AKI), which primarily stems from cellular injuries and ferroptosis caused by reactive oxygen species (ROS). Salidroside (SA), an antioxidant natural ester, has been attributed with the potential to protect against RIRI. In the present study, rats received daily SA doses (1, 10, or 100 mg/kg) by gavage for 7 consecutive days before surgery. The results revealed aggravated renal injury in the RIRI group, which was effectively prevented by SA pretreatment (10 and 100 mg/kg), with the 1 mg/kg dosage demonstrating lesser efficacy. Additionally, the results indicated that SA pretreatment mitigated the RIRI-related upregulation of antioxidative superoxide dismutase. In vitro studies corroborated SA's ability to maintain hypoxia/reoxygenation-treated NRK cell viability, with the protective effect being observed at SA concentrations ≥1 µM and peaking at 100 µM. Furthermore, the results showed that SA safeguarded renal tubular epithelial cells from oxidative damage, reduced ROS accumulation, and inhibited ferroptosis via activation of the PI3K/AKT signaling pathway. Therefore, the results of the present study highlight the promising therapeutic potential of SA as an effective intervention for RIRI via targeting of PI3K/AKT signaling pathway-mediated anti-oxidative and anti-ferroptotic mechanisms.

Ethanol Extract of Rosa rugosa Ameliorates Acetaminophen-Induced Liver Injury via Upregulating Sirt1 and Subsequent Potentiation of LKB1/AMPK/Nrf2 Cascade in Hepatocytes

Acetaminophen (APAP)-induced liver injury is a common hepatic disease resulting from drug abuse. Few targeted treatments are available clinically nowadays. The flower bud of Rosa rugosa has a wide range of biological activities. However, it is unclear whether it alleviates liver injury caused by APAP. Here, we prepared an ethanol extract of Rosa rugosa (ERS) and analyzed its chemical profile. Furthermore, we revealed that ERS significantly ameliorated APAP-induced apoptosis and ferroptosis in AML-12 hepatocytes and dampened APAP-mediated cytotoxicity. In AML-12 cells, ERS elevated Sirt1 expression, boosted the LKB1/AMPK/Nrf2 axis, and thereby crippled APAP-induced intracellular oxidative stress. Both EX527 and NAM, which are chemically unrelated inhibitors of Sirt1, blocked ERS-induced activation of LKB1/AMPK/Nrf2 signaling. The protection of ERS against APAP-triggered toxicity in AML-12 cells was subsequently abolished. As expression of LKB1 was knocked down, ERS still upregulated Sirt1 but failed to activate AMPK/Nrf2 cascade or suppress cytotoxicity provoked by APAP. Results of in vivo experiments showed that ERS attenuated APAP-caused hepatocyte apoptosis and ferroptosis and improved liver injury and inflammation. Consistently, ERS boosted Sirt1 expression, increased phosphorylations of LKB1 and AMPK, and promoted Nrf2 nuclear translocation in the livers of APAP-intoxicated mice. Hepatic transcriptions of HO-1 and GCLC, which are downstream antioxidant genes of Nrf2, were also significantly increased in response to ERS. Our results collectively indicated that ERS effectively attenuates APAP-induced liver injury by activating LKB1/AMPK/Nrf2 cascade. Upregulated expression of Sirt1 plays a crucial role in ERS-mediated activation of LKB1.

Novel hub genes and regulatory network related to ferroptosis in tetralogy of Fallot

Ferroptosis is a newly discovered type of cell death mainly triggered by uncontrolled lipid peroxidation, and it could potentially have a significant impact on the development and progression of tetralogy of Fallot (TOF). Our project aims to identify and validate potential genes related to ferroptosis in TOF. We obtained sequencing data of TOF from the GEO database and ferroptosis-related genes from the ferroptosis database. We employed bioinformatics methods to analyze the differentially expressed mRNAs (DEmRNAs) and microRNAs between the normal control group and TOF group and identify DEmRNAs related to ferroptosis. Protein-protein interaction analysis was conducted to screen hub genes. Furthermore, a miRNA-mRNA-TF co-regulatory network was constructed to utilize prediction software. The expression of hub genes was further validated through quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR). After conducting the differential gene analysis, we observed that in TOF, 41 upregulated mRNAs and three downregulated mRNAs associated with ferroptosis genes were found. Further Gene Ontology/Kyoto Encyclopedia of Genes and Genomes analysis revealed that these genes were primarily involved in molecular functions and biological processes related to chemical stress, oxidative stress, cellular response to starvation, response to nutrient levels, cellular response to external stimulus, and cellular response to extracellular stimulus. Furthermore, we constructed a miRNA-mRNA-TF co-regulatory network. qRT-PCR analysis of the right ventricular tissues from human cases showed an upregulation in the mRNA levels of KEAP1 and SQSTM1. Our bioinformatics analysis successfully identified 44 potential genes that are associated with ferroptosis in TOF. This finding significantly contributes to our understanding of the molecular mechanisms underlying the development of TOF. Moreover, these findings have the potential to open new avenues for the development of innovative therapeutic approaches for the treatment of this condition.

The Chains of Ferroptosis Interact in the Whole Progression of Atherosclerosis

Atherosclerosis (AS), a category of cardiovascular disease (CVD) that can cause other more severe disabilities, increasingly jeopardizes human health. Owing to its imperceptible and chronic symptoms, it is hard to determine the pathogenesis and precise therapeutics for AS. A novel type of programmed cell death called ferroptosis was discovered in recent years that is distinctively different from other traditional cell death pathways in morphological and biochemical aspects. Characterized by iron overload, redox disequilibrium, and accumulation of lipid hydroperoxides (L-OOH), ferroptosis influences endothelial cells, vascular smooth muscle cells (VSMCs), and macrophages, as well as inflammation, partaking in the pathology of many cardiovascular diseases such as atherosclerosis, stroke, ischemia-reperfusion injury, and heart failure. The mechanisms behind ferroptosis are so sophisticated and interwoven that many molecules involved in this procedure are unknown. This review systematically depicts the initiation and modulation of ferroptosis and summarizes the contribution of ferroptosis to AS, which may open a feasible approach for target treatment in the alleviation of AS progression.

The mechanism of ferroptosis and its related diseases

Ferroptosis, a regulated form of cellular death characterized by the iron-mediated accumulation of lipid peroxides, provides a novel avenue for delving into the intersection of cellular metabolism, oxidative stress, and disease pathology. We have witnessed a mounting fascination with ferroptosis, attributed to its pivotal roles across diverse physiological and pathological conditions including developmental processes, metabolic dynamics, oncogenic pathways, neurodegenerative cascades, and traumatic tissue injuries. By unraveling the intricate underpinnings of the molecular machinery, pivotal contributors, intricate signaling conduits, and regulatory networks governing ferroptosis, researchers aim to bridge the gap between the intricacies of this unique mode of cellular death and its multifaceted implications for health and disease. In light of the rapidly advancing landscape of ferroptosis research, we present a comprehensive review aiming at the extensive implications of ferroptosis in the origins and progress of human diseases. This review concludes with a careful analysis of potential treatment approaches carefully designed to either inhibit or promote ferroptosis. Additionally, we have succinctly summarized the potential therapeutic targets and compounds that hold promise in targeting ferroptosis within various diseases. This pivotal facet underscores the burgeoning possibilities for manipulating ferroptosis as a therapeutic strategy. In summary, this review enriched the insights of both investigators and practitioners, while fostering an elevated comprehension of ferroptosis and its latent translational utilities. By revealing the basic processes and investigating treatment possibilities, this review provides a crucial resource for scientists and medical practitioners, aiding in a deep understanding of ferroptosis and its effects in various disease situations.

TMT and PRM Based Quantitative Proteomics to Explore the Protective Role and Mechanism of Iristectorin B in Stroke

Stroke is a serious disease caused by the rupture or blockage of the cerebrovascular system. Its pathogenesis is complex and involves multiple mechanisms. Iristectorin B is a natural isoflavone that has certain anti stroke effects. In this study, an in vitro stroke injury model of glyoxylate deprivation was established using PC12 cells, which was used to evaluate the anti-stroke activity of Iristectorin B in ejecta stem. The results showed that Iristectorin B, a natural isoflavone derived from Dried Shoot, significantly reduced the damage to PC12 cells caused by oxygen glucose deprivation/reoxygenation, decreased apoptosis, enhanced cell survival and reduced Ca2+, LDH and ROS levels. The results showed that Iristectorin B had a significant protective effect on Na2S2O4-injured PC12 cells, and the mechanism may be related to the protective effect of neurons in the brain. After protein extraction and various analyses were performed, a series of cutting-edge technologies were organically combined to study the quantitative proteome of each group. Differential proteins were then analyzed. According to the protein screening principle, ferroptosis-related proteins were most closely associated with stroke. The differential proteins associated with ferroptosis screened were SLC3A2, TFR1 and HMOX1, with HMOX1 being the most significantly elevated and reduced via dosing. Iristectorin B may act as a protective agent against stroke by regulating ferroptosis, and SLC3A2, TFR1 and HMOX1 may serve as potential diagnostic biomarkers for stroke, providing additional evidence to support the importance of ferroptosis in stroke.

Unlocking Potentially Therapeutic Phytochemicals in Capadulla (Doliocarpus dentatus) from Guyana Using Untargeted Mass Spectrometry-Based Metabolomics

Doliocarpus dentatus is thought to have a wide variety of therapeutic phytochemicals that allegedly improve libido and cure impotence. Although a few biomarkers have been identified with potential antinociceptive and cytotoxic properties, an untargeted mass spectrometry-based metabolomics approach has never been undertaken to identify therapeutic biofingerprints for conditions, such as erectile dysfunction, in men. This study executes a preliminary phytochemical screening of the woody vine of two ecotypes of D. dentatus with renowned differences in therapeutic potential for erectile dysfunction. Liquid chromatography-mass spectrometry-based metabolomics was used to screen for flavonoids, terpenoids, and other chemical classes found to contrast between red and white ecotypes. Among the metabolite chemodiversity found in the ecotype screens, using a combination of GNPS, MS-DIAL, and SIRIUS, approximately 847 compounds were annotated at levels 2 to 4, with the majority of compounds falling under lipid and lipid-like molecules, benzenoids and phenylpropanoids, and polyketides, indicative of the contributions of the flavonoid, shikimic acid, and terpenoid biosynthesis pathways. Despite the extensive annotation, we report on 138 tentative compound identifications of potentially therapeutic compounds, with 55 selected compounds at a level-2 annotation, and 22 statistically significant therapeutic biomarkers, the majority of which were polyphenols. Epicatechin methyl gallate, catechin gallate, and proanthocyanidin A2 had the greatest significant differences and were also relatively abundant among the red and white ecotypes. These putatively identified compounds reportedly act as antioxidants, neutralizing damaging free radicals, and lowering cell oxidative stress, thus aiding in potentially preventing cellular damage and promoting overall well-being, especially for treating erectile dysfunction (ED).

Low-Dose Exposure of WS2 Nanosheets Induces Differential Apoptosis in Lung Epithelial Cells

Escalating the production and application of tungsten disulfide (WS2) nanosheets inevitably increases environmental human exposure and warrants the necessity of studies to elucidate their biological impacts. Herein, we assessed the toxicity of WS2 nanosheets and focused on the impacts of low doses (≤10 μg/mL) on normal (BEAS-2B) and tumorigenic (A549) lung epithelial cells. The low doses, which approximate real-world exposures, were found to induce cell apoptosis, while doses ≥ 50 μg/mL cause necrosis. Focused studies on low-dose exposure to WS2 nanosheets revealed more details of the impacts on both cell lines, including reduction of cell metabolic activity, induction of lipid peroxidation in cell membranes, and uncoupling of mitochondrial oxidative phosphorylation that led to the loss of ATP production. These phenomena, along with the expression situations of a few key proteins involved in apoptosis, point toward the occurrence of mitochondria-dependent apoptotic signaling in exposed cells. Substantial differences in responses to WS2 exposure between normal and tumorigenic lung epithelial cells were noticed as well. Specifically, BEAS-2B cells experienced more adverse effects and took up more nanosheets than A549 cells. Our results highlight the importance of dose and cell model selection in the assessment of nanotoxicity. By using doses consistent with real-world exposures and comparing normal and diseased cells, we can gain knowledge to guide the development of safety precautions for mitigating the adverse impacts of nanomaterial exposure on human health.

miR-432-5p Inhibits the Ferroptosis in Cardiomyocytes Induced by Hypoxia/Reoxygenation via Activating Nrf2/SLC7A11 Axis by Degrading Keap1

Early reperfusion into the myocardium after ischemia causes myocardial ischemia-reperfusion (I/R) injury and ferroptosis was involved. Ischemia activates the expression of a series of oxidative stress genes and their downstream regulatory genes, including ferroptosis-related genes such as nuclear factor E2-related factor 2 (Nrf2), glutathione peroxidase 4 (GPX4), and SLC7A11. This study adopted primary cardiomyocytes and I/R in rats to evaluate the ferroptosis and changing of Nrf2-SLC7A11/heme oxygenase-1 (HO-1) in vitro and in vivo. Online analysis tools were used to predict the possible target Kelch-like ECH-associated protein 1 (Keap1) of miR-432-5p. The mimic of miR-432-5p plasmid was constructed to verify the effect of miR-432-5p on ferroptosis. We found that hypoxia/reoxygenation (H/R) in cardiomyocytes and I/R in rats induced lipid peroxidation and ferroptosis in cardiomyocytes. The activation of the Nrf2-SLC7A11/HO-1 pathway protects cardiomyocytes from ferroptosis. Downregulation of miR-432-5p has been confirmed in H/R cardiomyocytes (in vitro) and cardiomyocytes in myocardial infarction rats (in vivo). Upregulation of miR-432-5p inhibited ferroptosis of cardiomyocytes induced by RAS-selective lethal 3 (RSL3), an inhibitor of GPX4 and ferroptosis inducer through decreasing the binding protein of Nrf2, Keap1, which was confirmed by bioinformatics and mutation assay. Knockdown Nrf2 attenuates the protection effect of miR-432-5p on H/R cardiomyocytes. Intravenous delivery of liposome carriers of miR-432-5p remarkably ameliorated cardiomyocyte impairment in the I/R animal model. In conclusion, miR-432-5p inhibits the ferroptosis in cardiomyocytes induced by H/R by activating Nrf2/SLC7A11 axis by degrading Keap1 and is a potential drug target for clinical myocardial infarction treatment.

The plasma exosomes from patients with primary Sjögren's syndrome contain epithelial cell-derived proteins involved in ferroptosis

Primary Sjögren's syndrome (pSS) is an autoimmune disease represented by exocrine gland epithelial cell lesions. However, the mechanism underlying these lesions remains unclear. This study analyzed the plasma exosomes of pSS patients using proteomics and revealed the presence of 24 differentially expressed proteins (DEPs) involved in the primary biological processes and signaling pathways related to ferroptosis. The DEPs enriched in the ferroptosis-related items were represented by downregulated ceruloplasmin (CP) and transferrin (TF). CC analysis of GO enrichment showed that CP and TF were localized at the apical plasma membrane, which is currently found only in epithelial cells. PPI analysis indicated that these exosomal DEPs formed a clustering network containing CP and TF. Among them, C5, C9, Haptoglobin (HP), and SERPING1 interacted directly with CP and TF. Notably, the expression of these proteins significantly decreased in both the pSS and secondary Sjögren's syndrome (sSS) plasma exosomes but not in non-autoimmune sicca syndrome (nSS). In addition, their expression levels were significantly different in the exosomes and plasma. More importantly, the plasma and salivary exosomes of pSS patients contain higher levels of exocrine gland epithelial autoantigens SSA and SSB than those of healthy controls, and epithelial cells with positive labial glands biopsy (LGB) were more susceptible to ferroptosis than those with negative LGB. The results indicated that ferroptosis may be closely related to SS epithelial cell lesions. KEY MESSAGES: • pSS plasma exosomes contain epithelial cell-derived proteins involved in ferroptosis. • Complement C5 and C9 may be new molecules involved in ferroptosis and play a crucial role in pSS epithelial cell pathology. • The serum exosomes from pSS patients, not nSS patients, contain ferroptosis-related proteins. • The changes in the ferroptosis-related protein content in the exosomes can better reflect the state of the epithelial cell lesions than those in the plasma.

Network pharmacology and experimental validation of Maxing Shigan decoction in the treatment of influenza virus-induced ferroptosis

Influenza is an acute viral respiratory infection that has caused high morbidity and mortality worldwide. Influenza A virus (IAV) has been found to activate multiple programmed cell death pathways, including ferroptosis. Ferroptosis is a novel form of programmed cell death in which the accumulation of intracellular iron promotes lipid peroxidation, leading to cell death. However, little is known about how influenza viruses induce ferroptosis in the host cells. In this study, based on network pharmacology, we predicted the mechanism of action of Maxing Shigan decoction (MXSGD) in IAV-induced ferroptosis, and found that this process was related to biological processes, cellular components, molecular function and multiple signaling pathways, where the hypoxia inducible factor-1(HIF-1) signaling pathway plays a significant role. Subsequently, we constructed the mouse lung epithelial (MLE-12) cell model by IAV-infected in vitro cell experiments, and revealed that IAV infection induced cellular ferroptosis that was characterized by mitochondrial damage, increased reactive oxygen species (ROS) release, increased total iron and iron ion contents, decreased expression of ferroptosis marker gene recombinant glutathione peroxidase 4 (GPX4), increased expression of acyl-CoA synthetase long chain family member 4 (ACSL4), and enhanced activation of hypoxia inducible factor-1α (HIF-1α), induced nitric oxide synthase (iNOS) and vascular endothelial growth factor (VEGF) in the HIF-1 signaling pathway. Treatment with MXSGD effectively reduced intracellular viral load, while reducing ROS, total iron and ferrous ion contents, repairing mitochondrial results and inhibiting the expression of cellular ferroptosis and the HIF-1 signaling pathway. Finally, based on animal experiments, it was found that MXSGD effectively alleviated pulmonary congestion, edema and inflammation in IAV-infected mice, and inhibited the expression of ferroptosis-related protein and the HIF-1 signaling pathway in lung tissues.