Ferroportin-dependent ferroptosis induced by ellagic acid retards liver fibrosis by impairing the SNARE complexes formation

Ellagic acid inhibits dihydrotestosterone-induced ferroptosis and promotes hair regeneration by activating the wnt/β-catenin signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Androgenic alopecia (AGA) is the most prevalent form of hair loss in clinical practice and affects the physical and psychological well-being of adolescents. Paeonia lactiflora Pallas (PL), which is widely used in traditional Chinese medicine, enhances blood function and promotes hair growth, and ellagic acid (EA), a polyphenol in PL extract, shows strong antioxidant, anti-aging, and anti-inflammatory properties and also plays a role in the treatment of various skin conditions. However, its role and mechanism of action in AGA remain unclear.

AIM OF THE STUDY

To determine whether EA can rescue slow hair regeneration by regulating dihydrotestosterone (DHT)-induced ferroptosis in AGA mice and clarify the effect of EA on DHT-induced ferroptosis in dermal papilla cells (DPCs).

MATERIALS AND METHODS

Male C57BL/6 mice were used to establish a DHT-induced AGA mouse model, whereas DPCs were used to establish a DHT-induced cellular model. Thereafter, we investigated the therapeutic mechanism of action of EA via immunofluorescence, western blot analysis, immunohistochemistry, electron microscopy, and molecular docking.

RESULTS

EA stimulated hair regeneration in mice and reversed DHT-induced increases in iron content, lipid peroxidation, and DHT-induced mitochondrial dysfunction by activating the Wnt/β-catenin signaling pathway. Further, β-catenin knockdown suppressed the inhibitory effect of EA on DHT-induced ferroptosis in DPCs.

CONCLUSION

EA inhibits DHT-induced ferroptosis and promotes hair regrowth in mice by activating the Wnt/β-catenin signaling pathway. Thus, it has potential for use as a treatment option for AGA.

Ferroptosis-Modulating Natural Products for Targeting Inflammation-Related Diseases: Challenges and Opportunities in Manipulating Redox Signaling

Significance: Numerous disorders are linked to ferroptosis, a form of programmed cell death triggered by lipid peroxidation accumulation rather than apoptosis. Inflammation is the body's defensive response to stimuli and is also caused by inflammatory chemicals that can harm the body. The treatment of inflammatory diseases by focusing on the signaling pathways and mechanisms of ferroptosis has emerged as a new area worthy of extensive research. Recent Advances: Studies in cellular and animal models of inflammatory diseases have shown that ferroptosis markers are activated and lipid peroxidation levels are increased. Natural products (NPs) are gaining importance due to their ability to target ferroptosis pathways, particularly the Nuclear factor E2-related factor 2 signaling pathway, thereby suppressing inflammation and the release of pro-inflammatory cytokines. Critical Issues: This article provides an overview of ferroptosis, focusing on the signaling pathways and mechanisms connecting it to inflammation. It also explores the potential use of NPs as a treatment for inflammatory diseases and ferroptosis. Future Directions: NPs offer unique advantages, including multicomponent properties, multi-bio-targeting capabilities, and minimal side effects. Further research may facilitate the early clinical application of NPs to develop innovative treatment strategies.

International consensus guidelines for the definition, detection, and interpretation of autophagy-dependent ferroptosis

Macroautophagy/autophagy is a complex degradation process with a dual role in cell death that is influenced by the cell types that are involved and the stressors they are exposed to. Ferroptosis is an iron-dependent oxidative form of cell death characterized by unrestricted lipid peroxidation in the context of heterogeneous and plastic mechanisms. Recent studies have shed light on the involvement of specific types of autophagy (e.g. ferritinophagy, lipophagy, and clockophagy) in initiating or executing ferroptotic cell death through the selective degradation of anti-injury proteins or organelles. Conversely, other forms of selective autophagy (e.g. reticulophagy and lysophagy) enhance the cellular defense against ferroptotic damage. Dysregulated autophagy-dependent ferroptosis has implications for a diverse range of pathological conditions. This review aims to present an updated definition of autophagy-dependent ferroptosis, discuss influential substrates and receptors, outline experimental methods, and propose guidelines for interpreting the results.Abbreviation: 3-MA:3-methyladenine; 4HNE: 4-hydroxynonenal; ACD: accidentalcell death; ADF: autophagy-dependentferroptosis; ARE: antioxidant response element; BH2:dihydrobiopterin; BH4: tetrahydrobiopterin; BMDMs: bonemarrow-derived macrophages; CMA: chaperone-mediated autophagy; CQ:chloroquine; DAMPs: danger/damage-associated molecular patterns; EMT,epithelial-mesenchymal transition; EPR: electronparamagnetic resonance; ER, endoplasmic reticulum; FRET: Försterresonance energy transfer; GFP: green fluorescent protein;GSH: glutathione;IF: immunofluorescence; IHC: immunohistochemistry; IOP, intraocularpressure; IRI: ischemia-reperfusion injury; LAA: linoleamide alkyne;MDA: malondialdehyde; PGSK: Phen Green™ SK;RCD: regulatedcell death; PUFAs: polyunsaturated fatty acids; RFP: red fluorescentprotein;ROS: reactive oxygen species; TBA: thiobarbituricacid; TBARS: thiobarbituric acid reactive substances; TEM:transmission electron microscopy.

Role of ferroptosis in fibrosis: From mechanism to potential therapy

ABSTRACT

Fibrosis, which is a manifestation of the physiological response to injury characterized by excessive accumulation of extracellular matrix components, is a ubiquitous outcome of the repair process. However, in cases of repetitive or severe injury, fibrosis may become dysregulated, leading to a pathological state and organ failure. In recent years, a novel form of regulated cell death, referred to as ferroptosis, has been identified as a possible contributor to fibrosis; it is characterized by iron-mediated lipid peroxidation. It has garnered attention due to the growing body of evidence linking ferroptosis and fibrogenesis, which is believed to be driven by underlying inflammation and immune responses. Despite the increasing interest in the relationship between ferroptosis and fibrosis, a comprehensive understanding of the precise role that ferroptosis plays in the formation of fibrotic tissue remains limited. This review seeks to synthesize previous research related to the topic. We categorized the different direct and indirect mechanisms by which ferroptosis may contribute to fibrosis into three categories: (1) iron overload toxicity; (2) ferroptosis-evoked necroinflammation, with a focus on ferroptosis and macrophage interplay; and (3) ferroptosis-associated pro-fibrotic factors and pathways. Furthermore, the review considers the potential implications of these findings and highlights the utilization of ferroptosis-targeted therapies as a promising strategy for mitigating the progression of fibrosis. In conclusion, novel anti-fibrotic treatments targeting ferroptosis could be an effective treatment for fibrosis.

Anti-NOTCH1 therapy with OMP-52 M51 inhibits salivary adenoid cystic carcinoma by depressing epithelial-mesenchymal transition (EMT) process and inducing ferroptosis

Salivary adenoid cystic carcinoma (ACC) is a common type of salivary gland cancer, and the mechanisms underlying its progression still remain poorly understood without efficient therapies. NOTCH1, an evolutionally conserved cell-cell signaling pathway, is involved in the progression of ACC. In our study, we attempted to explore whether NOTCH1 suppression using the monoclonal anti-NOTCH1 antibody OMP-52 M51 could be of potential for ACC treatment. Here, we identified NOTCH1 elevation in human ACC tissues compared with the matched normal samples. Patients with metastasis expressed much higher NOTCH1. We then found that OMP-52 M51 markedly reduced the expression of NOTCH1 and its intracellular active form NICD1 (NOTCH1 intracellular domain). Importantly, OMP-52 M51 markedly reduced the proliferation, migration and invasion of ACC cells. RNA-Seq and in vitro studies further showed that OMP-52 M51 significantly induced ferroptosis in ACC cells, indicated by the increased cellular malondialdehyde (MDA), iron contents and lipid ROS production, and decreased glutathione (GSH) levels. Further, remarkable glutathione peroxidase 4 (GPX4) reduction was detected in ACC cells with OMP-52 M51 treatment. However, promoting NOTCH1 expression markedly abolished the function of OMP-52 M51 to induce ferroptosis. Intriguingly, low-dose OMP-52 M51 strongly facilitated the capacity of ferroptosis inducer erastin to trigger ferroptotic cell death, revealing that OMP-52 M51 could improve the sensitivity of ACC cells to ferroptosis. In vivo, OMP-52 M51 administration suppressed tumor growth and induced ferroptosis in the constructed ACC xenograft mouse model. Collectively, our findings demonstrated that NOTCH1 inhibition by OMP-52 M51 represses the proliferation and epithelial-mesenchymal transition (EMT) in ACCs, and promotes ferroptosis, revealing the potential therapeutical application of OMP-52 M51 in ACC.

Integrating natural compounds and nanoparticle-based drug delivery systems: A novel strategy for enhanced efficacy and selectivity in cancer therapy

Cancer remains a leading cause of death worldwide, necessitating the development of innovative and more effective treatment strategies. Conventional cancer treatments often suffer from limitations such as systemic toxicity, poor pharmacokinetics, and drug resistance. Recently, there has been growing attention to utilizing natural compounds derived from various sources as possible cancer therapeutics. Natural compounds have demonstrated diverse bioactive properties, including antioxidant, anti-inflammatory, and antitumor effects, making them attractive candidates for cancer treatment. However, their limited solubility and bioavailability present challenges for effective delivery to cancer cells. To overcome these limitations, researchers have turned to nanotechnology-based drug delivery systems. Nanoparticles, with their small size and unique properties, can encapsulate therapeutic agents and offer benefits such as improved solubility, prolonged drug release, enhanced cellular uptake, and targeted delivery. Functionalizing nanoparticles with specific ligands further enhances their precision in recognizing and binding to cancer cells. Combining natural compounds with nanotechnology holds great promise in achieving efficient and safe cancer treatments by enhancing bioavailability, pharmacokinetics, and selectivity toward cancer cells. This review article provides an overview of the advancements in utilizing natural substances and nanotechnology-based drug delivery systems for cancer treatment. It discusses the benefits and drawbacks of various types of nanoparticles, as well as the characteristics of natural compounds that make them appealing for cancer therapy. Additionally, current research on natural substances and nanoparticles in preclinical and clinical settings is highlighted. Finally, the challenges and future perspectives in developing natural compound-nanoparticle-based cancer therapies are discussed.

Natural product-derived ferroptosis mediators

It has been 11 years since ferroptosis, a new mode of programmed cell death, was first proposed. Natural products are an important source of drug discovery. In the past five years, natural product-derived ferroptosis regulators have been discovered in an endless stream. Herein, 178 natural products discovered so far to trigger or resist ferroptosis are classified into 6 structural classes based on skeleton type, and the mechanisms of action that have been reported are elaborated upon. If pharmacodynamic data are sufficient, the structure and bioactivity relationship is also presented. This review will provide medicinal chemists with some effective ferroptosis regulators, which will promote the research of natural product-based treatment of ferroptosis-related diseases in the future.

The cell fate regulator DACH1 modulates ferroptosis through affecting P53/SLC25A37 signaling in fibrotic disease

BACKGROUND

Dachshund homolog 1 (DACH1) is widely acknowledged for its involvement in regulating diverse cell fates, but its precise regulatory mechanism in ferroptosis remains elusive. In this study, we investigated whether DACH1 modulates ferroptosis through affecting P53/solute carrier family 25 member 37 (SLC25A37) signaling in hepatic fibrogenesis.

METHODS

CRISPR-Cas9 system was used to knockout DACH1 in HSC to determine the effect of DACH1 on ferroptosis. Immunoprecipitation, pulldown, and mouse model of hepatic fibrogenesis were used to analyze the potential molecular mechanism of ferroptosis regulation by DACH1.

RESULTS

We found that ferroptosis inducers increased the protein expression of DACH1 by suppressing the ubiquitin-proteasome signaling. DACH1 knockout can resist ferroptosis, whereas DACH1 knockin can enhance it. Interestingly, the upregulation of DACH1 resulted in the mitochondrial translocation of p53 by inducing phosphorylation at serine 392. The mutation of serine 392 can prevent the combination of DACH1 and p53, the mitochondrial translocation of p53, and DACH1-mediated ferroptosis. Moreover, SLC25A37 was identified as a candidate target for mitochondrial p53. The binding of p53 to SLC25A37 can enhance the iron uptake capacity of SLC25A37, which may cause an overload of iron in the mitochondria and hyperactive mitochondrial electron transport chain. Knockdown of SLC25A37 can impair p53-mediated mitochondrial iron overload and ferroptosis. Furthermore, treatment with erastin can induce HSC ferroptosis and relieve fibrotic lesion damage in the mouse model of hepatic fibrogenesis. HSC-specific knockdown of DACH1, p53, and SLC25A37 can abolish the induction of HSC ferroptosis and reversal of hepatic fibrogenesis by erastin treatment.

CONCLUSIONS

Our findings suggest that the DACH1/P53/SLC25A37 signaling pathway is a promising target for fibrotic disorders and reveals new regulatory mechanisms of ferroptosis.

Ferroptosis in organ fibrosis: From mechanisms to therapeutic medicines

Fibrosis occurs in many organs, and its sustained progress can lead to organ destruction and malfunction. Although numerous studies on organ fibrosis have been carried out, its underlying mechanism is largely unknown, and no ideal treatment is currently available. Ferroptosis is an iron-dependent process of programmed cell death that is characterized by lipid peroxidation. In the past decade, a growing body of evidence demonstrated the association between ferroptosis and fibrotic diseases, while targeting ferroptosis may serve as a potential therapeutic strategy. This review highlights recent advances in the crosstalk between ferroptosis and organ fibrosis, and discusses ferroptosis-targeted therapeutic approaches against fibrosis that are currently being explored.

Ginsenoside Rg3 promotes hepatic stellate cell ferroptosis by epigenetically regulating ACSL4 to suppress liver fibrosis progression

BACKGROUND

Ginsenoside Rg3 (G-Rg3), extracted from Panax notoginseng, possesses hepatoprotective properties. Hepatic stellate cells (HSCs) activation is responsible for liver fibrosis. Recent studies have reported the suppressive effects of G-Rg3 on HSC activation and proliferation. Ferroptosis is a novel iron regulated cell death. ACSL4, a key indicator of ferroptosis, is commonly methylated in various diseases.

PURPOSE

However, the role of ACSL4 methylation-mediated HSC ferroptosis in G-Rg3 inhibition of hepatic fibrosis needs to be explored.

METHODS

Effects of G-Rg3 on inhibiting fibrosis were evaluated in vivo and in vitro. The impact of G-Rg3 on HSC ferroptosis was assessed in vitro. Furthermore, the expression of ACSL4, ACSL4 methylation and microRNA-6945-3p (miR-6945-3p) levels were determined.

RESULTS

G-Rg3 significantly alleviated CCl4-induced liver fibrosis, accompanied by collagen downregulation. In vitro, G-Rg3 contributed to HSC inactivation, leading to decreased collagen production. G-Rg3 induced HSC ferroptosis, characterized by increased iron accumulation, depletion of glutathione, malondialdehyde levels, and generation of lipid reactive oxygen species. Moreover, G-Rg3 promoted ACSL4 demethylation and restored its expression. Notably, DNMT3B counteracted the effect of G-Rg3-mediated inhibition of ACSL4 methylation and was targeted by miR-6945-3p. Further investigations revealed that G-Rg3 suppressed ACSL4 methylation through miR-6945-3p-mediated DNMT3B inhibition. Consistent with this, miR-6945-3p inhibition reversed G-Rg3-induced ACSL4 expression and HSC ferroptosis.

CONCLUSION

G-Rg3 inhibits ACSL4 methylation by miR-6945-3p-mediated DNMT3B inhibition, thereby promoting HSC ferroptosis and mitigating liver fibrosis.

Ellagic acid promotes osteoblasts differentiation via activating SMAD2/3 pathway and alleviates bone mass loss in OVX mice

Characterized by bone mass loss, osteoporosis is an orthopedic disease typically found in postmenopausal women and aging individuals. Consistent with its pathogenesis summarized as an imbalance in bone formation/resorption, current pharmacologically therapeutic strategies for osteoporosis mainly aim to promote bone formation or/and inhibit bone resorption. However, few effective drugs with mild clinical side effects have been developed, making it a well-concerned issue to seek appropriate drugs for osteoporosis. In this study, we investigated the effect of ellagic acid (EA) on osteogenesis in vitro and in vivo and searched for its molecular mechanism. Here, we showed that EA promoted osteogenic differentiation of MSCs, increased mRNA and protein expression levels of osteoblast marker genes Runt-related transcription factor2, Osterix, Alkaline phosphatase, Collagen type I alpha 1, Osteopontin and Osteocalcin. Furthermore, ovariectomized mice with orally administered EA (10 mg/kg, 50 mg/kg) had significantly higher bone mass than those in controls. And experiments such as fluorescence double-labeling and enzyme-linked immunosorbent assay also demonstrated that EA could promote osteogenesis in vivo. To probe the molecular mechanism of EA, we performed RNA sequencing analysis using EA-treated BMSCs. Significant up-regulation of SMAD2/3 transcription factors was identified by RNA-seq, and it was confirmed in vitro that EA promoted bone formation by activating the SMAD2/3 signaling pathway. Evidence from our present experiments indicates that EA may be a promising candidate for clinical treatment for osteoporosis in future.

Ellagic acid ameliorates renal fibrogenesis by blocking epithelial-to-mesenchymal transition

Objectives

Ellagic acid (EA), a kind of polyphenol found in numerous fruits and vegetables, has anti-inflammatory, anti-apoptotic, anti-oxidant, and anti-fibrotic effects against a variety of diseases, but its role in mediating renal fibrogenesis remains unknown.

Materials and Methods

We used an in vivo mouse unilateral ureteral obstruction (UUO) model and an in vitro model with HK-2 cell lines treated with EA and transforming growth factor β1 (TGF-β1). The expression of epithelial-to-mesenchymal transition (EMT)-related proteins of UUO mice was examined using immunohistochemical staining. Liver function and renal function were evaluated using biochemical testing. Western blot analysis was used to determine the proteins related to EMT, and MTT assay was used to determine cell viability.

Results

In UUO mice fed EA, both microscopical examination with immunohistochemical staining and western blotting protein analysis showed reduced expression of fibrotic (α-SMA, fibronectin, and collagen I)- and EMT (vimentin and N-cadherin)-related proteins, compared with sham control. In HK-2 cells treated with TGF-β1, EA decreased motility as well as expression of α-SMA, collagen-I, fibronectin, N-cadherin, and vimentin.

Conclusion

EA reduced the progression of the morphological transformations and concomitantly suppressed the expression of fibrotic- and EMT-related proteins in vitro and in vivo. These findings improved our understanding of the role of EA in suppressing renal fibrogenesis and demonstrated the promising role EA may play in the management of chronic kidney disease.

FTO-Mediated m6A Modification of FTH1 Inhibits Ferroptosis of Neurons in Neonatal Cerebral Hypoxic Ischemia

FTO alpha-ketoglutarate dependent dioxygenase (FTO) is aberrantly expressed in brain disorders. However, the roles of FTO in neonatal hypoxic-ischemic brain injury (HIE) are still unclear. This study aims to investigate the potential of FTO in neonatal HIE. Oxygen-glucose deprivation (OGD) was used to establish HIE in vitro. mRNA levels were detected by real-time reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR). Protein expression was detected by Western blot. The levels of malondialdehyde (MDA), superoxide dismutase (SOD), ferrous iron (Fe2+) and glutathione (GSH) was detected by specific kit. m6A sites were analyzed using SRAMP and further verify by methylated RNA immunoprecipitation (MeRIP) assay. Cell proliferation was determined by Cell Counting Kit-8 (CCK-8) assay. Cell death was determined by propidium iodide (PI) staining. FTO was downregulated in patients with neonatal HIE and OGD-treated neurons. Moreover, FTO mRNA expression was decreased in ferroptosis inducer, especially ferric ammonium citrate (FAC). However, overexpression of FTO inhibited the ferroptosis of neurons. Moreover, FTO-mediated N6-methyladenosine (m6A) modification of ferritin heavy chain 1 (FTH1) suppressed its mRNA expression and stability, inhibiting its protein expression. However, overexpression of FTH1 abrogated the effects of FTO and promoted the ferroptosis of neurons. In summary, FTO functions as a protective role in neonatal HIE via inhibiting FTH1 signaling. Thence, targeting may be a promising strategy for FTO neonatal HIE.

Modulation of the HIF-1α-NCOA4-FTH1 Signaling Axis Regulating Ferroptosis-induced Hepatic Stellate Cell Senescence to Explore the Anti-hepatic Fibrosis Mechanism of Curcumol

INTRODUCTION

Senescence of activated hepatic stellate cells (HSC) reduces extracellular matrix expression to reverse liver fibrosis. Ferroptosis is closely related to cellular senescence, but its regulatory mechanisms need to be further investigated. The iron ions weakly bound to ferritin in the cell are called labile iron pool (LIP), and together with ferritin, they maintain cellular iron homeostasis and regulate the cell's sensitivity to ferroptosis.

METHODS

We used lipopolysaccharide (LPS) to construct a pathological model group and divided the hepatic stellate cells into a blank group, a model group, and a curcumol 12.5 mg/L group, a curcumol 25 mg/L group, and a curcumol 50 mg/L group. HIF-1α-NCOA4- FTH1 signalling axis, ferroptosis and cellular senescence were detected by various cellular molecular biology experiments.

RESULT

We found that curcumol could induce hepatic stellate cell senescence by promoting iron death in hepatic stellate cells. Curcumol induced massive deposition of iron ions in hepatic stellate cells by activating the HIF-1α-NCOA4-FTH1 signalling axis, which further led to iron overload and lipid peroxidation-induced ferroptosis. Interestingly, our knockdown of HIF-1α rescued curcumol-induced LIP and iron deposition in hepatic stellate cells, suggesting that HIF-1α is a key target of curcumol in regulating iron metabolism and ferroptosis. We were able to rescue curcumol-induced hepatic stellate cell senescence when we reduced LIP and iron ion deposition using iron chelators.

CONCLUSION

Overall, curcumol induces ferroptosis and cellular senescence by increasing HIF-1α expression and increasing NCOA4 interaction with FTH1, leading to massive deposition of LIP and iron ions, which may be the molecular biological mechanism of its anti-liver fibrosis.

Natural Products in Liver Fibrosis Management: A Five-year Review

Liver fibrosis, characterized by the overproduction of extracellular matrix proteins within liver tissue, poses a rising global health concern. However, no approved antifibrotic drugs are currently available, highlighting the critical need for understanding the molecular mechanisms of liver fibrosis. This knowledge could not only aid in developing therapies but also enable early intervention, enhance disease prediction, and improve our understanding of the interaction between various underlying conditions and the liver. Notably, natural products used in traditional medicine systems worldwide and demonstrating diverse biochemical and pharmacological activities are increasingly recognized for their potential in treating liver fibrosis. This review aims to comprehensively understand liver fibrosis, emphasizing the molecular mechanisms and advancements in exploring natural products' antifibrotic potential over the past five years. It also acknowledges the challenges in their development and seeks to underscore their potency in enhancing patient prognosis and reducing the global burden of liver disease.

An Ellagic Acid Coordinated Copper-Based Nanoplatform for Efficiently Overcoming Cancer Chemoresistance by Cuproptosis and Synergistic Inhibition of Cancer Cell Stemness

Drug resistance is one of the leading causes of treatment failure in current cancer chemotherapy. In addition to the classical drug efflux transporter-mediated chemoresistance, cancer cells with stemness features play a crucial role in escaping the maximum impact of chemotherapy. To sensitize cancer chemotherapy, in a novel approach, the hedgehog pathway inhibitor ellagic acid (EA) is coordinated with Cu2+ to develop nanoscale metal-organic frameworks (EA-Cu), which are then loaded with doxorubicin (DOX) and modified with targeted chondroitin sulfate (CS) to form the CS/E-C@DOX nanoplatform (CS/NPs). Notably, EA inhibits stemness maintenance by suppressing the hedgehog pathway, while Cu2+ further decreases stemness features of tumor cells by disrupting mitochondrial metabolism, effectively enhancing DOX-mediated chemotherapy. Meanwhile, EA can act synergistically with Cu2+ to cause mitochondrial dysfunction and cuproptosis, which effectively decreases ATP levels and subsequently suppresses the activity of P-glycoprotein (P-gp), thus reducing drug efflux and sensitizing DOX-mediated chemotherapy. Additionally, the attached CS endows CS/NPs with specific tumor targeting properties, whereas EA-Cu endows this nanoplatform with pH/glutathione (GSH) dual-responsive release behavior. Taken together, CS/NPs exhibited excellent antitumor effects by inducing cuproptosis and significantly inhibiting cancer cell stemness, which has great potential for overcoming cancer chemoresistance.

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.

Schisandrin B Promotes Hepatic Stellate Cell Ferroptosis via Wnt Pathway-Mediated Ly6Clo Macrophages

A key event in liver fibrosis is the activation of the hepatic stellate cell (HSC). Schisandrin B (Sch B), a major component extracted from Schisandra chinensis, has been shown to inhibit HSC activation. Recently, ferroptosis (FPT) has been reported to be involved in HSC activation. However, whether Sch B has an effect on the HSC FPT remains unclear. Herein, we explored the effects of Sch B on liver fibrosis in vivo and in vitro and the roles of Wnt agonist 1 and ferrostatin-1 in the antifibrotic effects of Sch B. Sch B effectively alleviated CCl4-induced liver fibrosis, with decreased collagen deposition and α-SMA level. Additionally, Sch B resulted in an increase in lymphocyte antigen 6 complex locus C low (Ly6Clo) macrophages, contributing to a reduced level of TIMP1 and increased MMP2. Notably, the Wnt pathway was involved in Sch B-mediated Ly6C macrophage phenotypic transformation. Further studies demonstrated that Sch B-treated macrophages had an inhibitory effect on HSC activation, which was associated with HSC FPT. GPX4, a negative regulator of FPT, was induced by Sch B and found to be involved in the crosstalk between macrophage and HSC FPT. Furthermore, HSC inactivation as well as FPT induced by Sch B-treated macrophages was blocked down by Wnt pathway agonist 1. Collectively, we demonstrate that Sch B inhibits liver fibrosis, at least partially, through mediating Ly6Clo macrophages and HSC FPT. Sch B enhances Wnt pathway inactivation, leading to the increase in Ly6Clo macrophages, which contributes to HSC FPT. Sch B may be a promising drug for liver fibrosis treatment.

Recent progress in the effect of ferroptosis of HSCs on the development of liver fibrosis

Fibrosis is a common pathological process that must take place for multiple chronic liver diseases to develop into cirrhosis and liver cancer. Liver fibrosis (LF) is regulated by various cytokines and signaling pathways in its occurrence and development. Ferroptosis is an important mode of cell death caused by iron-dependent oxidative damage and is regulated by iron metabolism and lipid peroxidation signaling pathways. In recent years, numerous studies have shown that ferroptosis is closely related to LF. As the main material secreted by the extracellular matrix, hepatic stellate cells (HSCs) are a general concern in the development of LF. Therefore, targeting HSC ferroptosis against LF is crucial. This review describes the current status of treating LF by inducing HSC ferroptosis that would aid studies in better understanding the current knowledge on ferroptosis in HSCs and the future research direction in this field.

TUG1 protects against ferroptosis of hepatic stellate cells by upregulating PDK4-mediated glycolysis

The induction of ferroptosis in hepatic stellate cells (HSCs) has shown promise in reversing liver fibrosis. And ferroptosis has been confirmed to be associated with glycolysis. The objective of this study is to determine whether ferroptosis inhibition in HSCs, induced by elevation of recombinant pyruvate dehydrogenase kinase isozyme 4 (PDK4)-mediated glycolysis, could mediate the pathogenesis of liver fibrosis. Liver fibrosis was induced using CCl4, the level of which was assessed through histochemical staining. Lentivirus was used to modulate the expression of specific genes. And underlying mechanisms were explored using primary HSCs extracted from normal mice. The results confirmed that Taurine up-regulated gene 1 (TUG1) expression was upregulated in liver fibrotic tissues and HSCs, showing a positive correlation with fibrosis. In addition, TUG1 attenuated ferroptosis in HSCs by promoting PDK4-mediated glycolysis, thereby promoting the progression of liver fibrosis. Moreover, TUG1 was observed to impact HSCs activation, exacerbating liver fibrosis to some extent. In conclusion, our study revealed that TUG1 expression was elevated in mouse models of liver fibrosis and activated HSCs, which inhibited ferroptosis in HSCs through PDK4-mediated glycolysis. This finding may open up a new therapeutic strategy for liver fibrosis.

Photodynamic Therapy for Inflammatory and Cancerous Diseases of the Intestines: Molecular Mechanisms and Prospects for Application

Photodynamic therapy (PDT) is a minimally invasive treatment that effectively targets cancer and inflammatory diseases. It has gained recognition for its efficacy, low toxicity, and potential for repeated use. Colorectal cancer (CRC) and inflammatory bowel diseases (IBD), including Crohn's disease (CD), and ulcerative colitis (UC), impose a significant burden on global intestinal health, with increasing incidence and prevalence rates. PDT shows promise as an emerging approach for gastrointestinal disease treatment, particularly IBD and CRC. Extensive preclinical research has demonstrated the safety and effectiveness of PDT for IBD and CRC, while clinical studies are currently underway. This review provides an overview of the underlying mechanisms responsible for the anti-inflammatory and anti-tumor effects of PDT, offering insights into the clinical application of PDT in IBD and CRC treatment. It is expected that this review will serve as a valuable reference for future research on PDT for CRC and IBD, contributing to advancements in the treatment of inflammatory and cancerous diseases of the intestines.

Programmed Cell Death in Liver Fibrosis

Programmed cell death (PCD) is a comprehensive term that encompasses various forms of cell death, such as apoptosis, necroptosis, pyroptosis, ferroptosis, and autophagy, which play a crucial role in the pathogenesis of liver fibrosis. PCD facilitates the elimination of aberrant cells, particularly activated hepatic stellate cells (HSCs), which are the primary producers of extracellular matrix (ECM). The removal of HSCs may impede ECM synthesis, thereby mitigating liver fibrosis. As such, PCD has emerged as a promising therapeutic target for the development of novel drugs to treat liver fibrosis. Numerous studies have been conducted to investigate the underlying mechanisms of PCD in the elimination of activated HSCs and other aberrant liver cells in fibrotic liver tissue, including hepatocytes, hepatic sinusoid endothelial cells (LSECs), and Kupffer cells (KCs). The induction of PCD, the interplay between different forms of PCD, and the potential harm or benefit of PCD in liver fibrosis are topics of ongoing research. Evidences suggest that PCD is a complex process with dual effects on liver fibrosis. The purpose of this review is to summarize the most recent advances in PCD and liver fibrosis research.

Dissecting the potential role of ferroptosis in liver diseases: an updated review

Ferroptosis is a novel form of cell death, manifested by iron-dependent, non-apoptotic manner resulting from the intracellular accumulation of large clusters of reactive oxygen species (ROS) and lipid peroxides due to abnormal iron metabolism. Since the liver is the main organ of human body for storing iron, it is essential to perform in-depth investigation on the role and mechanistic basis of ferroptosis in the context of divergent liver diseases. We previously summarized the emerging role of ferroptosis among various liver diseases, however, the past few years have been a surge in research establishing ferroptosis as the molecular basis or treatment option. This review article concentrated on the accumulating research progress of ferroptosis in a range of liver diseases such as acute liver injury/failure (ALI/ALF), immune-mediated hepatitis, alcoholic liver disease (ALD), nonalcoholic fatty liver disease and liver fibrosis. Ferroptosis may be a promising target for the prevention and treatment of various liver diseases, providing a strategy for exploring new therapeutic avenues for these entities.

The advancements in targets for ferroptosis in liver diseases

Ferroptosis is a type of regulated cell death caused by iron overload and lipid peroxidation, and its core is an imbalance of redox reactions. Recent studies showed that ferroptosis played a dual role in liver diseases, that was, as a therapeutic target and a pathogenic factor. Therefore, herein, we summarized the role of ferroptosis in liver diseases, reviewed the part of available targets, such as drugs, small molecules, and nanomaterials, that acted on ferroptosis in liver diseases, and discussed the current challenges and prospects.

Pharmacological modulation of ferroptosis as a therapeutic target for liver fibrosis

Liver fibrosis, which is characterized by the excessive deposition of extracellular matrix (ECM) materials (primarily fibrillar collagen-I), is an abnormal repair reaction and pathological outcome of chronic liver diseases caused by alcohol abuse, non-alcoholic fatty liver disease, and chronic hepatitis B and C virus infections. Liver fibrosis often progresses to liver cirrhosis and hepatocellular carcinoma. Ferroptosis, characterized by lipid peroxidation, is a form of iron-dependent non-apoptotic cell death, and recent studies have reported that ferroptosis contribute to the development of liver fibrosis. Moreover, several agents have demonstrated therapeutic effects in experimental liver fibrosis models by inducing hepatic stellate cell (HSCs) ferroptosis. This review delineates the specific mechanism by which ferroptosis contributes to the development of liver fibrosis. Specifically, we focused on the different types of therapeutic agents that can induce HSCs ferroptosis and summarize their pharmacological effectiveness for liver fibrosis treatment. We suggest that HSCs ferroptosis may be a potential useful target of novel therapies for preventing and treating liver fibrosis.

Ferroptosis and its interaction with tumor immune microenvironment in liver cancer

Exploring effective systemic treatments for liver cancer is still a great challenge worldwide. As a novel form of regulated cell death, ferroptosis has been paid more and more attention in the cancer research field. In recent years, targeting ferroptosis has become an encouraging strategy for liver cancer treatment. Cancer cells can be directly killed by inducing ferroptosis; in contrast, ferroptosis can also ameliorate the tumor immunosuppressive microenvironment and sensitize cancers to immunotherapy. Here, we summarize fully current progress in the iron homeostasis in the liver, the internal association between imbalanced iron homeostasis and ferroptosis in liver carcinogenesis and development, as well as ferroptosis-related regulators in liver cancer. Furthermore, we discuss thoroughly the interaction between ferroptosis and tumor immune microenvironment. Finally, we provide certainly a future insight on the potential value of ferroptosis in the immunotherapy of liver cancer.

Targeting pancreatic stellate cells in chronic pancreatitis: Focus on therapeutic drugs and natural compounds

Chronic pancreatitis (CP) is a precancerous illness linked to pancreatic ductal adenocarcinoma (PDAC), although the evolutionary mechanism is uncertain. CP is distinguished by severe fibrosis caused by the activation of pancreatic stellate cells (PSCs). The current clinical therapeutic protocol for CP lacks specific therapeutic medicines for the prevention and suppression of inflammation and fibrosis aggravating in CP. More research on specifically targeting PSCs would help facilitate the development of novel therapies for pancreatic fibrosis. Notably, using natural compounds from medicinal plants as new antifibrotic agents has become a focus of recent research and is widely employed as an alternative and complementary approach. Our goal was to shed light on the role of PSCs in the development of CP and provide a focused update on the new potential therapeutic strategies against PSCs in CP models. Future studies can refer to these possible strategies for drug design, bioavailability, pharmacokinetics, and other issues to obtain better clinical outcomes for treating CP.

Ferroptosis: A potential target for the intervention of intervertebral disc degeneration

Ferroptosis, an iron-dependent form of programmed cell death marked by phospholipid peroxidation, is regulated by complex cellular metabolic pathways including lipid metabolism, iron balance, redox homeostasis, and mitochondrial activity. Initial research regarding the mechanism of ferroptosis mainly focused on the solute carrier family 7 member 11/glutathione/glutathione peroxidase 4 (GPX4) signal pathway. Recently, novel mechanisms of ferroptosis, independent of GPX4, have been discovered. Numerous pathologies associated with extensive lipid peroxidation, such as drug-resistant cancers, ischemic organ injuries, and neurodegenerative diseases, are driven by ferroptosis. Ferroptosis is a new therapeutic target for the intervention of IVDD. The role of ferroptosis in the modulation of intervertebral disc degeneration (IVDD) is a significant topic of interest. This is a novel research topic, and research on the mechanisms of IVDD and ferroptosis is ongoing. Herein, we aim to review and discuss the literature to explore the mechanisms of ferroptosis, the relationship between IVDD and ferroptosis, and the regulatory networks in the cells of the nucleus pulposus, annulus fibrosus, and cartilage endplate to provide references for future basic research and clinical translation for IVDD treatment.