ACSL4 is overexpressed in psoriasis and enhances inflammatory responses by activating ferroptosis

Anti-Inflammatory Effects of Curcumin-Based Nanoparticles Containing α-Linolenic Acid in a Model of Psoriasis In Vitro

Background/Objectives. Psoriasis is a common chronic skin inflammatory disorder pathogenetically associated with genetic, environmental, and immunological factors. The hallmarks of psoriatic lesions include sustained inflammation related to alterations in the innate and adaptive immune response, uncontrolled keratinocyte proliferation, differentiation, and death, as well as dysregulated crosstalk between immune cells and keratinocytes. In search of novel therapeutic strategies based on the use of natural products and dietary components to combine to the available conventional and innovative therapeutics, we explored the anti-inflammatory, antioxidant, and immunomodulatory activities of Curcumin (CU)-based solid lipid nanoparticles (SLNs) carrying the omega-3 fatty acid linolenic acid (LNA) in an in vitro model of psoriasis that had been previously constructed and characterized by us. Methods. This in vitro model consists of differentiated in vitro THP-1 macrophages (Mφs) and NCTC-2544 keratinocytes exposed or not to conditioned medium (CM) from Mφs treated with the Toll-like receptor-7 ligand imiquimod (IMQ). Results. In Mφs, the treatment with CU-LNA-SLNs inhibited the IMQ-induced expression of proinflammatory cytokines (IL-23, IL-8, IL-6: 43%, 26.5% and 73.7% inhibition, respectively, vs IMQ-treated Mφs), as well as the hyperproliferative response (12.8% inhibition vs IMQ-treated Mφs) and the increase in cell death observed in keratinocytes treated with Mφ-derived CM (64.7% inhibition). Moreover, in the same conditions, CU-LNA-SLNs reverted to control levels of the increased keratinocyte expression of two markers of ferroptosis, a form of death recently involved in the pathogenesis of psoriasis (TFRC and MDA: 13.4% and 56.1% inhibition, respectively). Conclusions. These results suggest that CU-LNA-SLNs could inhibit psoriatic inflammation, as well as the hyperproliferation and death of keratinocytes in psoriatic lesions, and could be considered as a new possible therapeutic strategy for psoriasis to be further evaluated for the topic treatment of psoriatic skin in vivo.

Combined Toxicity Assessment of Deoxynivalenol and Pb2+ on HK-2 Cells Involved in Excessive ROS-Induced Ferroptosis

The cocontamination of food by several mycotoxins and heavy metals poses significant health risks, and their combined toxic effects remain poorly understood. Particularly, specific studies exploring their combined impact on ferroptosis remain limited. In this work, we investigated the combined toxic effects of a mycotoxin, called deoxynivalenol (DON), and a heavy metal, called plumbum (Pb), and explored the potential mechanisms of DON and Pb co-occurrence via excessive ROS-induced ferroptosis in HK-2 cells. It was found that combined toxicity of DON and Pb2+ showed a synergism at low concentrations and an antagonism at high concentrations. The increase of the ROS level and iron content as well as the change expression of four ferroptosis marker proteins were observed in DON and Pb2+ individual and combined groups. Furthermore, the addition of ferroptosis inhibitor Fer-1 could mitigate the imbalance of oxidative stress and ferroptosis. Our results suggest that the co-occurrence of DON and Pb2+ might pose a slight threat to the nephrotoxicity due to the interactions related to the excessive ROS-induced ferroptosis, which would provide valuable insights into their potential combined toxic impacts to human and animal health.

Molecular mechanisms of ferroptosis in cardiovascular disease

Ferroptosis is a newly recognized type of regulated cell death that is characterized by the accumulation of iron and lipid peroxides in cells. Studies have shown that ferroptosis plays a significant role in the pathogenesis of various diseases, including cardiovascular diseases. In cardiovascular disease, ferroptosis is associated with ischemia-reperfusion injury, myocardial infarction, heart failure, and atherosclerosis. The molecular mechanisms underlying ferroptosis include the iron-dependent accumulation of lipid peroxidation products, glutathione depletion, and dysregulation of lipid metabolism, among others. This review aims to summarize the current knowledge of the molecular mechanisms of ferroptosis in cardiovascular disease and discuss the potential therapeutic strategies targeting ferroptosis as a treatment for cardiovascular disease.

Ferroptosis of select skin epithelial cells initiates and maintains chronic systemic immune-mediated psoriatic disease

Dysregulations of epithelial-immune interactions frequently culminate in chronic inflammatory diseases of the skin, lungs, kidneys, and gastrointestinal tract. Yet, the intraepithelial processes that initiate and perpetuate inflammation in these organs are poorly understood. Here, by utilizing redox lipidomics we identified ferroptosis-associated peroxidation of polyunsaturated phosphatidylethanolamines in the epithelia of patients with asthma, cystic fibrosis, psoriasis, and renal failure. Focusing on psoriasis as a disease model, we used high-resolution mass spectrometry imaging and identified keratin 14-expressing (K14-expressing) keratinocytes executing a ferroptotic death program in human psoriatic skin. Psoriatic phenotype with characteristic Th1/Th17 skin and extracutaneous immune responses was initiated and maintained in a murine model designed to actuate ferroptosis in a fraction of K14+ glutathione peroxidase 4-deficient (Gpx4-deficient) epidermal keratinocytes. Importantly, an antiferroptotic agent, liproxstatin-1, was as effective as clinically relevant biological IL-12/IL-23/TNF-α-targeting therapies or the depletion of T cells in completely abrogating molecular, biochemical, and morphological features of psoriasis. As ferroptosis in select epidermal keratinocytes triggers and sustains a pathological psoriatic multiorgan inflammatory circuit, we suggest that strategies targeting ferroptosis or its causes may be effective in preventing or ameliorating a variety of chronic inflammatory diseases.

Novel therapeutic approach for psoriasis: Upregulating FcRn to inhibit ferroptosis and alleviate lesional skin

Psoriasis, a chronic inflammatory skin disease, is characterized by complex immune dysregulation and oxidative stress responses. The neonatal Fc receptor (FcRn) plays a crucial role in the development of autoimmune diseases. Analysis of clinical psoriasis samples demonstrated a negative correlation between FcRn expression in skin lesions and disease severity. However, the role of FcRn in this process remains unclear. This study aimed to investigate the involvement of FcRn in the pathogenesis and progression of psoriasis. In an imiquimod (IMQ)-induced psoriasis-like mouse model, FcRn expression was significantly decreased in the lesional skin, and transcriptome sequencing of the skin revealed activation of the ferroptosis pathway in psoriasis. This led to the hypothesis that FcRn could potentially regulate ferroptosis via the signal transducer and activating transcription factor 3 (STAT3)/solute carrier family 7 member 11 (SLC7A11) axis. Further experiments showed exacerbated psoriasis-like lesional skin and ferroptosis in FcRn-knockout mice, whereas intervention with the ferroptosis inhibitor Fer-1 or STAT3 inhibitor Stattic alleviated these symptoms. Critical binding sites for the transcription factor STAT3 were identified in the SLC7A11 promoter region at positions -1185 and -564 using the luciferase reporter assays and chromatin immunoprecipitation. The administration of 1,4-naphthoquinone (NQ), an FcRn agonist, effectively alleviated psoriasis-like skin lesions by inhibiting ferroptosis. This study highlights the molecular mechanisms of action of FcRn in psoriasis and provides an experimental basis for the development of novel therapeutic strategies targeting FcRn.

MAPK14 as a key gene for regulating inflammatory response and macrophage M1 polarization induced by ferroptotic keratinocyte in psoriasis

Psoriasis is a prevalent condition characterized by chronic inflammation, immune dysregulation, and genetic alterations, significantly impacting the well-being of affected individuals. Recently, a novel aspect of programmed cell death, ferroptosis, linked to iron metabolism, has come to light. This research endeavors to unveil novel diagnostic genes associated with ferroptosis in psoriasis, employing bioinformatic methods and experimental validation. Diverse analytical strategies, including "limma," Weighted Gene Co-expression Network Analysis (WGCNA), Least Absolute Shrinkage and Selection Operator (LASSO), Support Vector Machine Recursive Feature Elimination (SVM-RFE), and Random Forest (RF), were employed to pinpoint pivotal ferroptosis-related diagnostic genes (FRDGs) in the training datasets GSE30999, testing dataset GSE41662 and GSE14905. The discriminative potential of FRDGs in distinguishing between normal and psoriatic patients was gauged using Receiver Operating Characteristic (ROC) curves, while the functional pathways of FRDGs were scrutinized through Gene Set Enrichment Analysis (GSEA). Spearman correlation and ssGSEA analysis were applied to explore correlations between FRDGs and immune cell infiltration or oxidative stress-related pathways. The study identified six robust FRDGs - PPARD, MAPK14, PARP9, POR, CDCA3, and PDK4 - which collectively formed a model boasting an exceptional AUC value of 0.994. GSEA analysis uncovered their active involvement in psoriasis-related pathways, and substantial correlations with immune cells and oxidative stress were noted. In vivo, experiments confirmed the consistency of the six FRDGs in the psoriasis model with microarray results. In vitro, genetic knockdown or inhibition of MAPK14 using SW203580 in keratinocytes attenuated ferroptosis and reduced the expression of inflammatory cytokines. Furthermore, the study revealed that intercellular communication between keratinocytes and macrophages was augmented by ferroptotic keratinocytes, increased M1 polarization, and recruitment of macrophage was regulated by MAPK14. In summary, our findings unveil novel ferroptosis-related targets and enhance the understanding of inflammatory responses in psoriasis. Targeting MAPK14 signaling in keratinocytes emerges as a promising therapeutic approach for managing psoriasis.

Nrf2-mediated ferroptosis inhibition: a novel approach for managing inflammatory diseases

Inflammatory diseases, including psoriasis, atherosclerosis, rheumatoid arthritis, and ulcerative colitis, are characterized by persistent inflammation. Moreover, the existing treatments for inflammatory diseases only provide temporary relief by controlling symptoms, and treatments of unstable and expensive. Therefore, new therapeutic solutions are urgently needed to address the underlying causes or symptoms of inflammatory diseases. Inflammation frequently coincides with a high level of (reactive oxygen species) ROS activation, serving as a fundamental element in numerous physiological and pathological phenotypes that can result in serious harm to the organism. Given its pivotal role in inflammation, oxidative stress, and ferroptosis, ROS represents a focal node for investigating the (nuclear factor E2-related factor 2) Nrf2 pathway and ferroptosis, both of which are intricately linked to ROS. Ferroptosis is mainly triggered by oxidative stress and involves iron-dependent lipid peroxidation. The transcription factor Nrf2 targets several genes within the ferroptosis pathway. Recent studies have shown that Nrf2 plays a significant role in three key ferroptosis-related routes, including the synthesis and metabolism of glutathione/glutathione peroxidase 4, iron metabolism, and lipid processes. As a result, ferroptosis-related treatments for inflammatory diseases have attracted much attention. Moreover, drugs targeting Nrf2 can be used to manage inflammatory conditions. This review aimed to assess ferroptosis regulation mechanism and the role of Nrf2 in ferroptosis inhibition. Therefore, this review article may provide the basis for more research regarding the treatment of inflammatory diseases through Nrf2-inhibited ferroptosis.

Computational recognition of regulator genes and signature for ferroptosis with implications on immunological properties and clinical management of atopic dermatitis

Background

Atopic dermatitis (AD) is a common chronic dermatitis of autoimmune origin that considerably affects the quality of life of patients. Ferroptosis, a newly regulated form of cell death, is essential for inflammation-related damage-associated molecular patterns (DAMPs). In this study, we aimed to identify ferroptosis regulators relevant to AD pathogenesis and reveal the mechanisms by which ferroptosis regulates the pathogenesis of AD.

Methods

We analyzed the GEO AD cohorts (GSE16161, GSE32924, GSE107361, and GSE120721), identifying AD-related differentially expressed genes (DEGs) using edgeR. Co-expression and STRING database analyses were used to elucidate the interactions between DEGs and ferroptosis markers. Through functional enrichment analysis, we defined potential biological functions within the protein-protein interaction (PPI) network and developed FerrSig using LASSO regression. The utility of FerrSig in guiding the clinical management of AD was evaluated using the GSE32473 cohort. Subsequently, our in silico findings were confirmed, and mechanistic insights were expanded through both in vitro and in vivo studies, validating the relevance of FerrSig.

Results

In the GEO AD cohort, 278 DEGs were identified, including seven ferroptosis signature genes. Co-expression analysis and STRING database review revealed a 63-node PPI network linked to cell cycle and pro-inflammatory pathways. Four ferroptosis genes (ALOXE3, FABP4, MAP3K14, and EGR1) were selected to create FerrSig, which was significantly downregulated in samples collected from patients with AD. In addition, immune-related signaling pathways were significantly differentially enriched between the stratifications of samples collected from patients with AD with high and low ferritin levels, whereas in the GSE32473 cohort, FerrSig was significantly increased in cohorts effectively treated with pimecrolimus or betamethasone. Finally, in vitro and in vivo models showed a notable FerrSig decrease in patients with AD versus healthy control. Treatment with betamethasone and tacrolimus restored FerrSig, and the magnitude of the increase in FerrSig was higher in samples collected from patients with AD with better efficacy assessments. In addition, FerrSig was significantly positively correlated with the ferroptosis inhibitors GPX4 and SLC7A11 and negatively correlated with reactive oxygen species (ROS) levels and p-STAT3/STAT3. This implies that the FerrSig signature genes may regulate ferroptosis through the JAK/STAT3 signaling pathway.

Conclusion

Our study further explored the pathogenesis of AD, and FerrSig could serve as a potential biomarker for identifying AD morbidity risks and determining treatment efficacy.

Investigating the anti-inflammatory effects of icariin: A combined meta-analysis and machine learning study

Objective

The objectives of this study were to define the superiority of icariin and its derivatives' anti-inflammatory activities and to create a reference framework for evaluating preclinical evidence. This method combines machine learning and meta-analysis to identify underlying biological pathways.

Methods

Data came from PubMed, Embase, Web of Science, and the Cochrane Library. SYRCLE was used to evaluate the risk of bias in a subset of research. Meta-analysis and detailed subgroup analyses, categorized by species, genders, disease type, dosage, and treatment duration, were performed using R and STATA 15.0 software to derive nuanced insights. Employing R software (version 4.2.3) and the tidymodels package, the analysis focused on constructing a model and selecting features, with TNF-α as the dependent variable. This approach aims to identify significant predictors of drug efficacy. An in-depth literature facilitated the synthesis of anti-inflammatory mechanisms attributed to icariin and its constituent compounds.

Results

Following a meticulous search and selection process, 19 studies, involving 370 and 260 animals were included in the meta-analysis and machine-learning assessment, respectively. The findings revealed that icariin and its derivatives markedly reduced inflammation markers, including TNF-α and IL-1β. Additionally, machine-learning outcomes, with TNF-α as the target variable, indicated enhanced anti-inflammatory effects of icariin across respiratory, urological, neurological, and digestive disease types. These effects were more pronounced at doses exceeding 27.52 mg/kg/day and treatment durations beyond 31.22 days.

Conclusion

Strong anti-inflammatory effects are exhibited by icariiin and its derivatives, which are especially beneficial in the management of digestive, neurological, pulmonary, and urinary conditions. Effective for periods longer than 31.22 days and at dosages more than 27.52 mg/kg/day. Subsequent research will involve more targeted animal experiments and safety assessments to obtain more comprehensive preclinical evidence.

Molecular and therapeutic landscape of ferroptosis in skin diseases

ABSTRACT

Regulated cell death (RCD) is a critical physiological process essential in maintaining skin homeostasis. Among the various forms of RCD, ferroptosis stands out due to its distinct features of iron accumulation, lipid peroxidation, and involvement of various inhibitory antioxidant systems. In recent years, an expanding body of research has solidly linked ferroptosis to the emergence of skin disorders. Therefore, understanding the mechanisms underlying ferroptosis in skin diseases is crucial for advancing therapy and prevention strategies. This review commences with a succinct elucidation of the mechanisms that underpin ferroptosis, embarks on a thorough exploration of ferroptosis's role across a spectrum of skin conditions, encompassing melanoma, psoriasis, systemic lupus erythematosus (SLE), vitiligo, and dermatological ailments precipitated by ultraviolet (UV) exposure, and scrutinizes the potential therapeutic benefits of pharmacological interventions aimed at modulating ferroptosis for the amelioration of skin diseases.

Skin Aging and the Upcoming Role of Ferroptosis in Geroscience

The skin is considered the most important organ system in mammals, and as the population ages, it is important to consider skin aging and anti-aging therapeutic strategies. Exposure of the skin to various insults induces significant changes throughout our lives, differentiating the skin of a young adult from that of an older adult. These changes are caused by a combination of intrinsic and extrinsic aging. We report the interactions between skin aging and its metabolism, showing that the network is due to several factors. For example, iron is an important nutrient for humans, but its level increases with aging, inducing deleterious effects on cellular functions. Recently, it was discovered that ferroptosis, or iron-dependent cell death, is linked to aging and skin diseases. The pursuit of new molecular targets for ferroptosis has recently attracted attention. Prevention of ferroptosis is an effective therapeutic strategy for the treatment of diseases, especially in old age. However, the pathological and biological mechanisms underlying ferroptosis are still not fully understood, especially in skin diseases such as melanoma and autoimmune diseases. Only a few basic studies on regulated cell death exist, and the challenge is to turn the studies into clinical applications.

Exploration of ferroptosis and necroptosis-related genes and potential molecular mechanisms in psoriasis and atherosclerosis

Objective

Ferroptosis and necroptosis are two recently identified forms of non-apoptotic cell death. Their dysregulation plays a critical role in the development and progression of Psoriasis (PsD) and Atherosclerosis (AS). This study explores shared Ferroptosis and necroptosis-related genes and elucidates their molecular mechanisms in PsD and AS through the analysis of public databases.

Methods

Data sets for PsD (GSE30999) and AS (GSE28829) were retrieved from the GEO database. Differential gene expression (DEG) and weighted gene co-expression network analysis (WGCNA) were performed. Machine learning algorithms identified candidate biomarkers, whose diagnostic values were assessed using Receiver Operating Characteristic (ROC) curve analysis. Additionally, the expression levels of these biomarkers in cell models of AS and PsD were quantitatively measured using Western Blot (WB) and real-time quantitative PCR (RT-qPCR). Furthermore, CIBERSORT evaluated immune cell infiltration in PsD and AS tissues, highlighting the correlation between characteristic genes and immune cells. Predictive analysis for candidate drugs targeting characteristic genes was conducted using the DGIdb database, and an lncRNA-miRNA-mRNA network related to these genes was constructed.

Results

We identified 44 differentially expressed ferroptosis-related genes (DE-FRGs) and 30 differentially expressed necroptosis-related genes (DE-NRGs). GO and KEGG enrichment analyses revealed significant enrichment of these genes in immune-related and inflammatory pathways, especially in NOD-like receptor and TNF signaling pathways. Two ferroptosis-related genes (NAMPT, ZFP36) and eight necroptosis-related genes (C7, CARD6, CASP1, CTSD, HMOX1, NOD2, PYCARD, TNFRSF21) showed high sensitivity and specificity in ROC curve analysis. These findings were corroborated in external validation datasets and cell models. Immune infiltration analysis revealed increased levels of T cells gamma delta, Macrophages M0, and Macrophages M2 in PsD and AS samples. Additionally, we identified 43 drugs targeting 5 characteristic genes. Notably, the XIST-miR-93-5p-ZFP36/HMOX1 and NEAT1-miR-93-5p-ZFP36/HMOX1 pathways have been identified as promising RNA regulatory pathways in AS and PsD.

Conclusion

The two ferroptosis-related genes (NAMPT, ZFP36) and eight necroptosis-related genes (C7, CARD6, CASP1, CTSD, HMOX1, NOD2, PYCARD, TNFRSF21) are potential key biomarkers for PsD and AS. These genes significantly influence the pathogenesis of PsD and AS by modulating macrophage activity, participating in immune regulation, and mediating inflammatory responses.

Advances in research on immunocyte iron metabolism, ferroptosis, and their regulatory roles in autoimmune and autoinflammatory diseases

Autoimmune diseases commonly affect various systems, but their etiology and pathogenesis remain unclear. Currently, increasing research has highlighted the role of ferroptosis in immune regulation, with immune cells being a crucial component of the body's immune system. This review provides an overview and discusses the relationship between ferroptosis, programmed cell death in immune cells, and autoimmune diseases. Additionally, it summarizes the role of various key targets of ferroptosis, such as GPX4 and TFR, in immune cell immune responses. Furthermore, the release of multiple molecules, including damage-associated molecular patterns (DAMPs), following cell death by ferroptosis, is examined, as these molecules further influence the differentiation and function of immune cells, thereby affecting the occurrence and progression of autoimmune diseases. Moreover, immune cells secrete immune factors or their metabolites, which also impact the occurrence of ferroptosis in target organs and tissues involved in autoimmune diseases. Iron chelators, chloroquine and its derivatives, antioxidants, chloroquine derivatives, and calreticulin have been demonstrated to be effective in animal studies for certain autoimmune diseases, exerting anti-inflammatory and immunomodulatory effects. Finally, a brief summary and future perspectives on the research of autoimmune diseases are provided, aiming to guide disease treatment strategies.

Identification of Potential Ferroptosis Biomarkers and Analysis of Immune Cell Infiltration in Psoriasis Using Machine Learning

Background

Ferroptosis is a type of cell death characterized by the accumulation of iron-dependent lethal lipid peroxides, which is associated with various pathophysiological processes. Psoriasis is a chronic autoimmune skin disease accompanied by abnormal immune cell infiltration and excessive production of lipid reactive oxygen species (ROS). Currently, its pathogenesis remains elusive, especially the potential role of ferroptosis in its pathophysiological process.

Methods

The microarrays GSE13355 (58 psoriatic skin specimens versus 122 healthy skin specimens) and the ferroptosis database were employed to identify the common differentially expressed genes (DEGs) associated with psoriasis and ferroptosis. The functions of common DEGs were investigated through functional enrichment analysis and protein-protein interaction analysis. The potential diagnostic markers for psoriasis among the common DEGs were identified using four machine-learning algorithms. DGIdb was utilized to explore potential therapeutic agents for psoriasis. Additionally, CIBERSORT was employed to investigate immune infiltration in psoriasis.

Results

A total of 8 common DEGs associated with psoriasis and ferroptosis were identified, which are involved in intercellular signaling and affect pathways of cell response to stress and stimulation. Four machine-learning algorithms were employed to identify poly (ADP-ribose) polymerase 12 (PARP12), frizzled homolog 7 (FZD7), and arachidonate 15-lipoxygenase (ALOX15B) among the eight common DEGs as potential diagnostic markers for psoriasis. A total of 18 drugs targeting the five common DEGs were identified as potential candidates for treating psoriasis. Additionally, significant changes were observed in the immune microenvironment of patients with psoriasis.

Conclusion

This study has contributed to our enhanced comprehension of ferroptosis-related genes as potential biomarkers for psoriasis diagnosis, as well as the alterations in the immune microenvironment associated with psoriasis. Our findings offer valuable insights into the diagnosis and treatment of psoriasis.

Ironing out the role of ferroptosis in immunity

Ferroptosis is a type of regulated cell death that drives the pathophysiology of many diseases. Oxidative stress is detectable in many types of regulated cell death, but only ferroptosis involves lipid peroxidation and iron dependency. Ferroptosis originates and propagates from several organelles, including the mitochondria, endoplasmic reticulum, Golgi, and lysosomes. Recent data have revealed that immune cells can both induce and undergo ferroptosis. A mechanistic understanding of how ferroptosis regulates immunity is critical to understanding how ferroptosis controls immune responses and how this is dysregulated in disease. Translationally, more work is needed to produce ferroptosis-modulating immunotherapeutics. This review focuses on the role of ferroptosis in immune-related diseases, including infection, autoimmune diseases, and cancer. We discuss how ferroptosis is regulated in immunity, how this regulation contributes to disease pathogenesis, and how targeting ferroptosis may lead to novel therapies.

Ferroptosis in acute kidney injury following crush syndrome: A novel target for treatment

BACKGROUND

Crush syndrome (CS) is a kind of traumatic and ischemic injury that seriously threatens life after prolonged compression. It is characterized by systemic inflammatory reaction, myoglobinuria, hyperkalemia and acute kidney injury (AKI). Especially AKI, it is the leading cause of death from CS. There are various cell death forms in AKI, among which ferroptosis is a typical form of cell death. However, the role of ferroptosis has not been fully revealed in CS-AKI.

AIM OF REVIEW

This review aimed to summarize the evidence of ferroptosis in CS-AKI and its related molecular mechanism, discuss the therapeutic significance of ferroptosis in CS-AKI, and open up new ideas for the treatment of CS-AKI.

KEY SCIENTIFIC CONCEPTS OF REVIEW

One of the main pathological manifestations of CS-AKI is renal tubular epithelial cell dysfunction and cell death, which has been attributed to massive deposition of myoglobin. Large amounts of myoglobin released from damaged muscle deposited in the renal tubules, impeding the normal renal tubules function and directly damaging the tubules with oxidative stress and elevated iron levels. Lipid peroxidation damage and iron overload are the distinguishing features of ferroptosis. Moreover, high levels of pro-inflammatory cytokines and damage-associated molecule pattern molecules (HMGB1, double-strand DNA, and macrophage extracellular trap) in renal tissue have been shown to promote ferroptosis. However, how ferroptosis occurs in CS-AKI and whether it can be a therapeutic target remains unclear. In our current work, we systematically reviewed the occurrence and underlying mechanism of ferroptosis in CS-AKI.

4-Octyl itaconate inhibits inflammation to attenuate psoriasis as an agonist of oxeiptosis

Psoriasis is a highly prevalent chronic disease associated with a substantial social and economic burden. Oxeiptosis is a programmed cell death that occurs when cells are in a state of high oxidative stress, which has a potent anti-inflammatory effect. However, there is still no research on oxeiptosis in psoriasis, and the agonists or antagonists of oxeiptosis remain an unclear field. Here, we found that oxeiptosis of keratinocytes was inhibited in psoriasis lesions. KEAP1, as the upstream molecular component of oxeiptosis, is highly expressed in psoriasis lesions. Knockdown of KEAP1 in HaCaT cells caused oxeiptosis in the condition of M5 cocktail stimulation. Next, we found that the cell-permeable derivative of itaconate, 4-octylitaconate (OI) promoted oxeiptosis of keratinocytes by inhibiting KEAP1 and then activating PGAM5 which are two upstream molecular components of oxeiptosis. At the same time, OI can reduce the expression of inflammatory cytokines induced by M5 cocktail stimulation in vitro. Similarly, we found that OI can alleviate IMQ-induced psoriatic lesions in mice and downregulate the levels of inflammatory cytokines in psoriatic lesions. In summary, our findings suggest that oxeiptosis of keratinocytes was inhibited in psoriasis and OI can significantly inhibit inflammation and alleviate psoriasis as an agonist of oxeiptosis, indicating that oxeiptosis may be involved in regulating the progression of psoriasis, which may provide new therapeutic targets for psoriasis treatment.

Shikonin promotes ferroptosis in HaCaT cells through Nrf2 and alleviates imiquimod-induced psoriasis in mice

Psoriasis is one kind of autoimmune skin disease without efficiency cure. Shikonin (SHK) is a potential drug for psoriasis treatment. Recent study suggested that ferroptosis involved in the pathological process of psoriasis. This study proved the beneficial effect of SHK with an imiquimod (IMQ) induced psoriatic model mice, and studied the ferroptosis regulative mechanism of SHK with a HaCaT cells assay in vitro. In the study, it also found that SHK treatment significantly improved imiquimod (IMQ)-induced psoriasis symptoms in mice, attenuated the production of inflammatory cytokines, including interleukin (IL)-6, IL-17, and tumor necrosis factor-alpha (i.e., TNF-α), and strongly inhibited macrophage infiltration in inflamed psoriatic skin. SHK impacted HaCaT cells (a human keratinocyte cell line) viability by enhancing intracellular and mitochondrial ferrous and lipid peroxidation levels by regulating expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), nuclear receptor coactivator 4 (NCOA4) and glutathione peroxidase 4 (GPX4) which could be reversed by iron chelating agent. and in psoriatic dermatitis. However, this study found the reversing capability of low dose SHK on LPS inhibited GPX4 and Nrf2 expression, which was identity to that in psoriatic dermatitis. To conclude, SHK inhibited ferroptosis in psoriatic skin by reducing inflammation, ameliorating oxidative stress and iron accumulation. Nrf2 and GPX4 might be the two major targets of SHK in psoriatic skin lesion. Our study highly lighted the basic biological mechanism of SHK on ferroptosis regulation.

Lipid Peroxidation of the Docosahexaenoic Acid/Arachidonic Acid Ratio Relating to the Social Behaviors of Individuals with Autism Spectrum Disorder: The Relationship with Ferroptosis

Polyunsaturated fatty acids (PUFAs) undergo lipid peroxidation and conversion into malondialdehyde (MDA). MDA reacts with acetaldehyde to form malondialdehyde-modified low-density lipoprotein (MDA-LDL). We studied unsettled issues in the association between MDA-LDL and the pathophysiology of ASD in 18 individuals with autism spectrum disorders (ASD) and eight age-matched controls. Social behaviors were assessed using the social responsiveness scale (SRS). To overcome the problem of using small samples, adaptive Lasso was used to enhance the interpretability accuracy, and a coefficient of variation was used for variable selections. Plasma levels of the MDA-LDL levels (91.00 ± 16.70 vs. 74.50 ± 18.88) and the DHA/arachidonic acid (ARA) ratio (0.57 ± 0.16 vs. 0.37 ± 0.07) were significantly higher and the superoxide dismutase levels were significantly lower in the ASD group than those in the control group. Total SRS scores in the ASD group were significantly higher than those in the control group. The unbeneficial DHA/ARA ratio induced ferroptosis via lipid peroxidation. Multiple linear regression analysis and adaptive Lasso revealed an association of the DHA/ARA ratio with total SRS scores and increased MDA-LDL levels in plasma, resulting in neuronal deficiencies. This unbeneficial DHA/ARA-ratio-induced ferroptosis contributes to autistic social behaviors and is available for therapy.

NAT10, an RNA Cytidine Acetyltransferase, Regulates Ferroptosis in Cancer Cells

Recently, we reported that N-acetyltransferase 10 (NAT10) regulates fatty acid metabolism through ac4C-dependent RNA modification of key genes in cancer cells. During this work, we noticed ferroptosis as one of the most negatively enriched pathways among other pathways in NAT10-depleted cancer cells. In the current work, we explore the possibility of whether NAT10 acts as an epitranscriptomic regulator of the ferroptosis pathway in cancer cells. Global ac4C levels and expression of NAT10 with other ferroptosis-related genes were assessed via dotblot and RT-qPCR, respectively. Flow cytometry and biochemical analysis were used to assess oxidative stress and ferroptosis features. The ac4C-mediated mRNA stability was conducted using RIP-PCR and mRNA stability assay. Metabolites were profiled using LC-MS/MS. Our results showed significant downregulation in expression of essential genes related to ferroptosis, namely SLC7A11, GCLC, MAP1LC3A, and SLC39A8 in NAT10-depleted cancer cells. Further, we noticed a reduction in cystine uptake and reduced GSH levels, along with elevated ROS, and lipid peroxidation levels in NAT10-depleted cells. Consistently, overproduction of oxPLs, as well as increased mitochondrial depolarization and decreased activities of antioxidant enzymes, support the notion of ferroptosis induction in NAT10-depleted cancer cells. Mechanistically, a reduced ac4C level shortens the half-life of GCLC and SLC7A11 mRNA, resulting in low levels of intracellular cystine and reduced GSH, failing to detoxify ROS, and leading to increased cellular oxPLs, which facilitate ferroptosis induction. Collectively, our findings suggest that NAT10 restrains ferroptosis by stabilizing the SLC7A11 mRNA transcripts in order to avoid oxidative stress that induces oxidation of phospholipids to initiate ferroptosis.

Reversal of H2O2-induced cell death by knockdown of HOTAIR in HTR-8/SVneo cells by mediation of miR-106b-5p/ACSL4 axis

Preeclampsia is a serious threat to the health of pregnant women. Injury of trophoblasts could contribute to the progression of preeclampsia, and H₂O₂ was able to induce apoptosis in trophoblasts. LncRNAs have been reported to be involved in the progression of preeclampsia. Additionally, lncRNA HOTAIR is upregulated in patients with preeclampsia. However, the function of HOTAIR in H₂O₂-treated trophoblasts remains unclear. To explore the function of HOTAIR in preeclampsia, HTR-8/SVneo cells were stimulated with H₂O₂. RT-qPCR was performed to measure HOTAIR expression in HTR-8/SVneo cells. The apoptosis of HTR-8/SVneo cells was measured using TUNEL staining. The mitochondrial membrane potential was measured using JC-1 staining. Western blotting was performed to detect the expression of ACSL4, GPX4, and FTH1 in HTR-8/SVneo cells. The level of HOTAIR in HTR-8/SVneo cells was upregulated by H₂O₂. In addition, H₂O₂ notably inhibited the proliferation of HTR-8/SVneo cells, whereas knockdown of HOTAIR reversed this phenomenon. The mitochondrial membrane potential in HTR-8/SVneo cells was significantly inhibited by H₂O₂ and partially abolished by HOTAIR silencing. Moreover, HOTAIR could bind to miR-106b-5p; ACSL4 was identified as the downstream target of miR-106b-5p. Furthermore, HOTAIR knockdown reversed H₂O₂-induced ferroptosis in HTR-8/SVneo cells by regulating miR-106b-5p/ACSL4. Collectively, the knockdown of HOTAIR reversed H₂O₂-induced ferroptosis in HTR-8/SVneo cells by mediating miR-106b-5p/ACSL4. Thus, HOTAIR may serve as a new therapeutic target against preeclampsia.