Wogonoside attenuates liver fibrosis by triggering hepatic stellate cell ferroptosis through SOCS1/P53/SLC7A11 pathway

Targeting the regulation of iron homeostasis as a potential therapeutic strategy for nonalcoholic fatty liver disease

With aging and the increasing incidence of obesity, nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease worldwide. NAFLD mainly includes simple hepatic steatosis, nonalcoholic steatohepatitis (NASH), liver fibrosis and hepatocellular carcinoma (HCC). An imbalance in hepatic iron homeostasis is usually associated with the progression of NAFLD and induces iron overload, reactive oxygen species (ROS) production, and lipid peroxide accumulation, which leads to ferroptosis. Ferroptosis is a unique type of programmed cell death (PCD) that is characterized by iron dependence, ROS production and lipid peroxidation. The ferroptosis inhibition systems involved in NAFLD include the solute carrier family 7 member 11 (SLC7A11)/glutathione (GSH)/glutathione peroxidase 4 (GPX4) and ferroptosis suppressor protein 1 (FSP1)/coenzyme Q10 (CoQ10)/nicotinamide adenine dinucleotide phosphate (NADPH) regulatory axes. The main promotion system involved is the acyl-CoA synthetase long-chain family (ACSL4)/arachidonic lipoxygenase 15 (ALOX15) axis. In recent years, an increasing number of studies have focused on the multiple roles of iron homeostasis imbalance and ferroptosis in the progression of NAFLD. This review highlights the latest studies about iron homeostasis imbalance- and ferroptosis-associated NAFLD, mainly including the physiology and pathophysiology of hepatic iron metabolism, hepatic iron homeostasis imbalance during the development of NAFLD, and key regulatory molecules and roles of hepatic ferroptosis in NAFLD. This review aims to provide innovative therapeutic strategies for NAFLD.

LncRNA FRMD6-AS1/miR-491-5p/USP13 pathway attenuated ferroptosis and contributed to liver fibrosis

Liver fibrosis is an invertible pathophysiologic process featured by excessive accumulation of extracellular matrix (ECM) which injures liver cells and activates hepatic stellate cells (HSCs). Besides, inducing ferroptosis in activated HSCs can alleviate liver fibrosis. LncRNAs modulate ferroptosis in activated HSCs and ECM deposition in liver fibrosis. However, the role of lncRNA FRMD6-AS1 in liver fibrosis is not discovered. In this study, lncRNA FRMD6-AS1 was dramatically up-regulated in activated HSCs. Knockdown of FRMD6-AS1 markedly increased iron ion, ROS and MDA levels, decreased GSH level, SLC7A11 and GPX4 protein expressions in activated HSCs. In addition, HSCs activation markers α-SMA and COL1α1 expressions were up-regulated in activated HSCs; knockdown of FRMD6-AS1 markedly down-regulated α-SMA and COL1α1 expressions in HSCs. Besides, lncRNA FRMD6-AS1 could interact with miR-491-5p, and negatively modulate miR-491-5p expression. USP13 was a target of miR-491-5p, and could be negatively modulated by miR-491-5p. Moreover, FRMD6-AS1 knockdown increased iron ion and ROS levels, decreased SLC7A11 and GPX4 protein expressions, facilitated HSCs viability, and up-regulated α-SMA and COL1α1 expressions via miR-491-5p/USP13 pathway. Finally, FRMD6-AS1 knockdown restored liver tissue structure and abrogated fibrosis in livers in a CCL4 liver fibrosis mouse model. Hence, lncRNA FRMD6-AS1/miR-491-5p/USP13 pathway repressed ferroptosis, promoted ECM deposition and facilitated liver fibrosis in vitro and in vivo models.

Targeting tumor suppressor p53 for organ fibrosis therapy

Fibrosis is a reparative and progressive process characterized by abnormal extracellular matrix deposition, contributing to organ dysfunction in chronic diseases. The tumor suppressor p53 (p53), known for its regulatory roles in cell proliferation, apoptosis, aging, and metabolism across diverse tissues, appears to play a pivotal role in aggravating biological processes such as epithelial-mesenchymal transition (EMT), cell apoptosis, and cell senescence. These processes are closely intertwined with the pathogenesis of fibrotic disease. In this review, we briefly introduce the background and specific mechanism of p53, investigate the pathogenesis of fibrosis, and further discuss p53's relationship and role in fibrosis affecting the kidney, liver, lung, and heart. In summary, targeting p53 represents a promising and innovative therapeutic approach for the prevention and treatment of organ fibrosis.

Mesenchymal stem cell-derived exosomal miR-26a induces ferroptosis, suppresses hepatic stellate cell activation, and ameliorates liver fibrosis by modulating SLC7A11

Liver fibrosis is a key contributor to hepatic disease-related mortality. Exosomes derived from mesenchymal stem cells (MSCs) have been revealed to improve liver fibrosis. To explore the effect and mechanism of MSC-derived exosomal miR-26a on liver fibrosis, exosomes were separated from bone marrow-derived MSCs (BMSCs) and used to treat with LX2 cells. The miR-26a level was decreased in BMSC-derived exosomes. Treatment with exosomes isolated from human BMSCs transfected with miR-26a mimics (miR-26a mimic-Exo) decreased the 5-ethynyl-2'-deoxyuridine-positive cell rate, the protein level of α-SMA and collagen I, and the glutathione (GSH) level but enhanced the apoptosis rate and the reactive oxide species (ROS) level in LX2 cells, which were reversed by the treatment of deferoxamine. Mechanically, miR-26a directly bound SLC7A11 mRNA and negatively modulated the level of SLC7A11 in LX2 cells. Overexpression of SLC7A11 reversed the miR-26a mimic-Exo-induced alterations in the level of ROS, Fe2+, malonaldehyde, and GSH in LX2 cells. In vivo, miR-26a mimic-Exo decreased the level of SLC7A11 and attenuated CCL4-induced liver fibrosis. Collectively, miR-26a mimic-Exo induced ferroptosis to alleviate liver fibrosis by regulating SLC7A11, which may provide new strategies for the treatment of liver fibrosis, and even other relevant diseases.

IL-13 facilitates ferroptotic death in asthmatic epithelial cells via SOCS1-mediated ubiquitinated degradation of SLC7A11

Th2-high asthma is characterized by elevated levels of type 2 cytokines, such as interleukin 13 (IL-13), and its prevalence has been increasing worldwide. Ferroptosis, a recently discovered type of programmed cell death, is involved in the pathological process of Th2-high asthma; however, the underlying mechanisms remain incompletely understood. In this study, we demonstrated that the serum level of malondialdehyde (MDA), an index of lipid peroxidation, positively correlated with IL-13 level and negatively correlated with the predicted forced expiratory volume in 1 s (FEV1%) in asthmatics. Furthermore, we showed that IL-13 facilitates ferroptosis by upregulating of suppressor of cytokine signaling 1 (SOCS1) through analyzing immortalized airway epithelial cells, human airway organoids, and the ovalbumin (OVA)-challenged asthma model. We identified that signal transducer and activator of transcription 6 (STAT6) promotes the transcription of SOCS1 upon IL-13 stimulation. Moreover, SOCS1, an E3 ubiquitin ligase, was found to bind to solute carrier family 7 member 11 (SLC7A11) and catalyze its ubiquitinated degradation, thereby promoting ferroptosis in airway epithelial cells. Last, we found that inhibiting SOCS1 can decrease ferroptosis in airway epithelial cells and alleviate airway hyperresponsiveness (AHR) in OVA-challenged wide-type mice, while SOCS1 overexpression exacerbated the above in OVA-challenged IL-13-knockout mice. Our findings reveal that the IL-13/STAT6/SOCS1/SLC7A11 pathway is a novel molecular mechanism for ferroptosis in Th2-high asthma, confirming that targeting ferroptosis in airway epithelial cells is a potential therapeutic strategy for Th2-high asthma.

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.

Ginkgolic acid inhibits the expression of SAE1 and induces ferroptosis to exert an anti-hepatic fibrosis effect

BACKGROUND

Finding a drug for early intervention in the hepatic fibrosis process has important clinical significance. Previous studies have suggested SUMOylation as a potential target for intervention in hepatic fibrosis. However, the role of SAE1, a marker of SUMOylation, in hepatic fibrosis is unknown. Additionally, whether ginkgolic acid (GA), a SUMOylation inhibitor, inhibits hepatic fibrosis by inhibiting SUMO1-activating enzyme subunit 1 (SAE1) should be further investigated.

METHODS

Liver tissues of patients with hepatic cirrhosis and a rat model of hepatic fibrosis constructed with CCl4 (400 mg/kg, twice weekly) or TAA (200 mg/kg, twice weekly) were selected, and the degree of hepatic fibrosis was then evaluated using H&E, Sirius red, and Masson's trichrome staining. After knockdown or overexpression of SAE1 in hepatic stellate cells, the expression levels of ferroptosis and hepatic fibrosis markers were measured in vitro. After intervention with a ferroptosis inhibitor, the expression levels were again measured in vivo and in vitro.

RESULTS

We first demonstrated that SAE1 increased in patients with hepatic cirrhosis. Subsequently, testing of the rat hepatic fibrosis model confirmed that GA reduced the expression of SAE1 and improved hepatic fibrosis in rats. Then, we used hepatic stellate cell lines to confirm in vitro that GA inhibited SAE1 expression and induced ferroptosis, and that overexpression of SAE1 or inhibition of ferroptosis reversed this process. Finally, we confirmed in vivo that GA induced ferroptosis and alleviated the progression of hepatic fibrosis, while inhibiting ferroptosis also reversed the progression of hepatic fibrosis in rats.

CONCLUSION

SAE1 is a potential anti-fibrotic target protein, and GA induces ferroptosis of hepatic stellate cells by targeting SAE1 to exert an anti-hepatic fibrosis effect, which lays an experimental foundation for the future clinical application of its anti-hepatic fibrosis effect.

Ferroptosis: a new hunter of hepatocellular carcinoma

Ferroptosis is an iron ion-dependent, regulatory cell death modality driven by intracellular lipid peroxidation that plays a key role in the development of HCC. Studies have shown that various clinical agents (e.g., sorafenib) have ferroptosis inducer-like effects and can exert therapeutic effects by modulating different key factors in the ferroptosis pathway. This implies that targeting tumor cell ferroptosis may be a very promising strategy for tumor therapy. In this paper, we summarize the prerequisites and defense systems for the occurrence of ferroptosis and the regulatory targets of drug-mediated ferroptosis action in HCC, the differences and connections between ferroptosis and other programmed cell deaths. We aim to summarize the theoretical basis, classical inducers of ferroptosis and research progress of ferroptosis in HCC cells, clued to the treatment of HCC by regulating ferroptosis network. Further investigation of the specific mechanisms of ferroptosis and the development of hepatocellular carcinoma and interventions at different stages of hepatocellular carcinoma will help us to deepen our understanding of hepatocellular carcinoma, with a view to providing new and more precise preventive as well as therapeutic measures for patients.

Angong Niuhuang Wan inhibit ferroptosis on ischemic and hemorrhagic stroke by activating PPARγ/AKT/GPX4 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Angong Niuhuang Wan (AGNHW) is a prescription from traditional Chinese medicine (TCM) that has been used for centuries to treat ischemic stroke (IS) and hemorrhagic stroke (HS). According to a recent study, targeting ferroptosis might be effective in the management of IS and HS. However, the ferroptosis-related effects and mechanisms of AGNHW have not yet been reported.

AIM OF THE STUDY

This research examines the anti-ferroptosis mechanisms of AGNHW in the treatment of IS and HS.

MATERIALS AND METHODS

A system pharmacological approach including in vivo experiment, UHPLC-Q-Orbitrap HRMS, network pharmacology, molecular docking, microscale thermophoresis, and in vitro experiment was utilized to study the anti-ferroptosis mechanisms of AGNHW against IS and HS.

RESULTS

In vivo experiments indicated that AGNHW enhanced nerve function, decreased cerebral infarct volume, ameliorated histological brain injuries, improved the structural integrity of the blood-brain barrier, ameliorated the mitochondrial dysfunction and morphology disruption, and inhibits ROS, LPO and Fe2+ accumulations in IS and HS rats. Using UHPLC-Q-Orbitrap HRMS, the key ingredients of AGNHW-containing serum were identified as bilirubin, berberine, baicalin, and wogonoside. According to the network pharmacology analyses, AGNHW could inhibit ferroptosis by modulating the PPAR and PI3K/AKT signaling pathways. The core targets are PPARγ, AKT, and GPX4. Molecular docking and microscale thermophoresis experiments further revealed that the key ingredients have strong interactions with ferroptosis-regulating core proteins. Moreover, in vitro experiment results showed that AGNHW alleviated ferroptosis injury induced by erastin in PC12 cells, increased cell viability, reduced the LPO and Fe2+ levels, and up-regulated mRNA expressions of PPARγ, AKT, and GPX4. AGNHW also up-regulated protein expressions of PPARγ, p-AKT/AKT, and GPX4 in IS and HS rats.

CONCLUSIONS

AGNHW attenuated ferroptosis in treating IS and HS by targeting the PPARγ/AKT/GPX4 pathway. This work reveals AGNHW's anti-ferroptosis mechanism against IS and HS, but it also develops an integrated approach to demonstrate the common characteristics of drugs in treating different diseases.

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.

Cannabidiol regulates the activation of hepatic stellate cells by modulating the NOX4 and NF-κB pathways

Cannabidiol (CBD) is an extract of natural cannabinoids that has therapeutic implications for a variety of ailments, such as neurological diseases, cardiomyopathy, and diabetes, due to its strong anti-inflammatory and oxidative stress properties. Our purpose was to reveal the possible underlying mechanisms and effect of CBD on the glucose oxidase (GO)-induced activation of HSC-T6 and LX-2 cells. The results showed that CBD effectively inhibited the proliferation and activation of HSC-T6 and LX-2 cells, and reduced the production of profibrotic factors to different degrees. CBD disrupted the NOX4 signalling pathway in activated HSC-T6 and LX-2 cells, reduced ROS and MDA levels, and increased SOD and GSH levels, thereby stabilizing the oxidative imbalance. CBD significantly inhibited the phosphorylation and degradation of NF-κB and IκBα, and decreased the release of TNF-α, IL-1β and IL-6. Moreover, CBD and an NF-κB-specific inhibitor (CAPE) effectively inhibited the expression of α-SMA, COL I, TNF-α and IL-1β to promote collagen metabolism and inhibit the inflammatory response. Overall, CBD inhibited HSCs activation through a and the mechanism involving the inhibition of NOX4 and NF-κB-dependent ROS regulation, thereby reducing inflammation and ameliorating oxidative imbalances.

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.

Targeting ferroptosis with natural products in liver injury: new insights from molecular mechanisms to targeted therapies

BACKGROUND

Ferroptosis is a brand-new type of controlled cell death that is distinguished by its reliance on iron and the production of lipid peroxidation. The role of ferroptosis in damaging liver disorders has attracted a lot of attention in recent years. One effective strategy to reduce liver damage is to target ferroptosis.

PURPOSE

The purpose of this review is to clarify the connection between ferroptosis and liver damage and to look into the potential contribution of natural products to the clinical management of liver damage and the discovery of novel medications.

METHODS

To study the methods by which natural products operate on ferroptosis to cure liver damage and their main signaling pathways, we searched databases from the time of initial publication to August 2023 in PubMed, EMBASE, Web of Science, Ovid, ScienceDirect, and China National Knowledge Infrastructure. The liver illness that each natural product treats is categorized and summarized. It's interesting to note that several natural compounds, such Artemether, Fucoidan sulfate, Curcumin, etc., have the benefit of having many targets and multiple pathways of action.

RESULTS

We saw that in human samples or animal models of liver injury, ferroptosis indicators were activated, lipid peroxidation levels were elevated, and iron inhibitors had the ability to reduce liver damage. Liver damage can be treated with natural products by regulating ferroptosis. This is mostly accomplished through the modulation of Nrf2-related pathways (e.g., Conclusions and Astaxanthin), biological enzymes like GPX4 and the SIRT family (e.g., Chrysophanol and Decursin), and transcription factors like P53 (e.g., Artemether and Zeaxanthin).

CONCLUSIONS

This review proposes a promising path for the therapeutic therapy of liver damage by providing a theoretical foundation for the management of ferroptosis utilizing natural ingredients.

Isoliquiritin treatment of osteoporosis by promoting osteogenic differentiation and autophagy of bone marrow mesenchymal stem cells

Osteoporosis is a chronic progressive bone disease characterized by the decreased osteogenic ability of osteoblasts coupled with increased osteoclast activity. Natural products showing promising therapeutic potential for postmenopausal osteoporosis remain underexplored. In this study, we aimed to analyze the therapeutic effects of isoliquiritin (ISL) on osteoporosis in mice and its possible mechanism of action. An ovariectomy-induced osteoporosis mouse model and bone marrow mesenchymal stem cells (BMSCs) were used to analyze the effects of ISL on bone regeneration in vivo and in vitro, respectively. Mitogen-activated protein kinase (MAPK) and autophagy inhibitors were used, to investigate whether the MAPK signaling pathway and autophagy affect the osteogenic differentiation of BMSCs. ISL significantly improved bone formation and reduced bone resorption in mouse femurs without inducing any detectable toxicity in critical organs such as the liver, kidney, brain, heart, and spleen. In vitro experiments showed that ISL enhanced the proliferation and osteogenic differentiation of BMSCs and that its osteogenic effect was attenuated by p38/extracellular regulated protein kinase (ERK) and autophagy inhibitors. Further studies showed that the inhibition of phosphorylated p38/ERK blocked ISL autophagy in BMSCs. ISL promoted the osteogenic differentiation of BMSCs through the p38/ERK-autophagy pathway and was therapeutically effective in treating osteoporosis in ovariectomized mice without any observed toxicity to vital organs. These results strongly suggest the promising potential of ISL as a safe and efficacious candidate drug for the treatment of osteoporosis.

PURPL Promotes M2 Macrophage Polarization in Lung Cancer by Regulating RBM4/xCT Signaling

Lung cancer is the most common malignancy worldwide. Long non-coding RNA (lncRNA) p53 upregulated regulator of P53 levels (PURPL) is abnormally in various cancers. However, the reports on its roles in lung cancer are limited. The purpose of present study is to investigate the potentials of lncRNA PURPL in lung cancer. PURPL and mRNA expression was determined using real-time reverse transcriptase-polymerase chain reaction (RT-qPCR). The location of PURPL was detected using RNA fluorescence in situ hybridization (FISH) assay. Protein expression was detected using western blot. Cellular functions were determined using flow cytometry. The interaction between PURPL and RNA-binding motif 4 (RBM4) was confirmed using RNA immunoprecipitation (RIP) assay. PURPL was overexpressed in lung cancer cells and patients. Overexpressed PURPL promoted M2 macrophage polarization and suppressed ferroptosis. Additionally, PURPL maintained the mRNA stability of cystine glutamate reverse transporter (xCT) via regulating RBM4. xCT knockdown antagonized the effects of overexpressed PURPL and inhibited M2 macrophage polarization via inducing macrophage ferroptosis. PURPL/RBM4/xCT axis promoted M2 macrophage polarization in lung cancer. Therefore, PURPL may be a potential target of lung cancer.

Effects of Natural Products on Enzymes Involved in Ferroptosis: Regulation and Implications

Ferroptosis is a form of regulated cell death that is characterized by the accumulation of iron-dependent lipid peroxides. The regulation of ferroptosis involves both non-enzymatic reactions and enzymatic mechanisms. Natural products have demonstrated potential effects on various enzymes, including GPX4, HO-1, NQO1, NOX4, GCLC, and GCLM, which are mainly involved in glutathione metabolic pathway or oxidative stress regulation, and ACSL3 and ACSL4, which mainly participate in lipid metabolism, thereby influencing the regulation of ferroptosis. In this review, we have provided a comprehensive overview of the existing literature pertaining to the effects of natural products on enzymes involved in ferroptosis and discussed their potential implications for the prevention and treatment of ferroptosis-related diseases. We also highlight the potential challenge that the majority of research has concentrated on investigating the impact of natural products on the expression of enzymes involving ferroptosis while limited attention is given to the regulation of enzyme activity. This observation underscores the considerable potential and scope for exploring the influence of natural products on enzyme activity.

Resveratrol inhibits ferroptosis and decelerates heart failure progression via Sirt1/p53 pathway activation

Resveratrol is an organic compound widely studied for its therapeutic uses. We investigated whether resveratrol exerts cardioprotective effects by inhibiting ferroptosis via the Sirt1/p53 pathway. A heart failure model was established by aortic coarctation in Sirt1 knockout mice. The superoxide dismutase (SOD), glutathione (GSH) levels and mitochondrial morphology in murine heart tissues were assessed at different time points to determine the role of ferroptosis in heart failure progression. The cardiac function of mice with heart failure was evaluated by determining the brain natriuretic peptide (BNP) and sST2 concentration and conducting echocardiography. Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were transfected with the p53 K382R mutant and Sirt1 interference lentiviral vectors. Immunoprecipitation (IP) experiments were performed to investigate whether Sirt1 influences ferroptosis via p53 K382 acetylation and SLC7A11 expression modulation. Resveratrol improved cardiac function in mice and decelerated ferroptosis and fibrosis progression in heart failure. However, the ability of resveratrol to prevent ferroptosis and treat heart failure was lost after silencing Sirt1. Sirt1 reduced ferroptosis by diminishing the levels of p53 K382 acetylation, reducing the degradation of SLC7A11, and increasing the levels of GSH and glutathione peroxidase 4 (GPX4) in cells. In conclusion, by activating the Sirt1/p53 pathway in heart failure, resveratrol decreased the depletion of SLC7A11, inhibited ferroptosis, and improved cardiac function.

Managing ferroptosis-related diseases with indirect dietary modulators of ferroptosis

Ferroptosis is an iron-dependent form of programmed cell death driven by excessive oxidation of polyunsaturated phospholipids on cellular membranes. Accumulating evidence suggests that ferroptosis has been implicated in the pathological process of various diseases, such as cardiovascular diseases, neurological diseases, liver diseases, kidney injury, lung injury, diabetes, and cancer. Targeting ferroptosis is therefore considered to be a reasonable strategy to fight against ferroptosis-associated diseases. Many dietary bioactive agents have been identified to be able to either suppress or promote ferroptosis, indicating that ferroptosis-based intervention by dietary approach may be an effective strategy for preventing and treating diseases associated with ferroptosis dysregulation. In this review, we summarize the present understanding of the functional role of ferroptosis in the pathogenesis of aforementioned diseases with an emphasis on the evidence of managing ferroptosis-related diseases with indirect dietary modulators of ferroptosis and propose issues that need to be addressed to promote practical application of dietary approach targeting ferroptosis.

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.

Ferroptosis as an emerging therapeutic target in liver diseases

Ferroptosis is an iron-dependently nonapoptotic cell death characterized by excessive accumulation of lipid peroxides and cellular iron metabolism disturbances. Impaired iron homeostasis and dysregulation of metabolic pathways are contributors to ferroptosis. As a major metabolic hub, the liver synthesizes and transports plasma proteins and endogenous fatty acids. Also, it acts as the primary location of iron storage for hepcidin generation and secretion. To date, although the intricate correlation between ferroptosis and liver disorders needs to be better defined, there is no doubt that ferroptosis participates in the pathogenesis of liver diseases. Accordingly, pharmacological induction and inhibition of ferroptosis show significant potential for the treatment of hepatic disorders involved in lipid peroxidation. In this review, we outline the prominent features, molecular mechanisms, and modulatory networks of ferroptosis and its physiopathologic functions in the progression of liver diseases. Further, this review summarizes the underlying mechanisms by which ferroptosis inducers and inhibitors ameliorate liver diseases. It is noteworthy that natural active ingredients show efficacy in preclinical liver disease models by regulating ferroptosis. Finally, we analyze crucial concepts and urgent issues concerning ferroptosis as a novel therapeutic target in the diagnosis and therapy of liver diseases.

Exploring the effect of Yinzhihuang granules on alcoholic liver disease based on pharmacodynamics, network pharmacology and molecular docking

BACKGROUND

Yinzhihuang granules (YZHG) is a commonly used Chinese patent medicine for the treatment of liver disease. However, the mechanism of YZHG in alcoholic liver disease (ALD) is still unclear.

METHODS

This study combined liquid chromatography-mass spectrometry technology, pharmacodynamics, network pharmacology and molecular docking methods to evaluate the potential mechanism of YZHG in the treatment of ALD.

RESULTS

A total of 25 compounds including 4-hydroxyacetophenone, scoparone, geniposide, quercetin, baicalin, baicalein, chlorogenic acid and caffeic acid in YZHG were identified by ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The pharmacodynamic investigations indicated that YZHG could improve liver function and the degree of liver tissue lesions, and reduce liver inflammation and oxidative stress in ALD mice. Network pharmacology analysis showed that YZHG treated ALD mainly by regulating inflammation-related signaling pathways such as the PI3K-Akt signaling pathway. The results of the PPI network and molecular docking showed that the targets of SRC, HSP90AA1, STAT3, EGFR and AKT1 could be the key targets of YZHG in the treatment of ALD.

CONCLUSION

This study explored the potential compounds, potential targets and signaling pathways of YZHG in the treatment of ALD, which is helpful to clarify the efficacy and mechanism of YZHG and provide new insights for the clinical application of YZHG.

Ferroptosis is involved in polymyxin B-induced acute kidney injury via activation of p53

Polymyxin B (PMB) is one of the most effective drugs for the treatment of multi-resistant and pan-resistant gram-negative infections. However, it can induce acute kidney injury (AKI), the mechanism of which has not yet been fully elucidated. In this study, RNA sequencing and in vitro and in vivo experiments demonstrated that PMB induced AKI by promoting ferroptosis. Moreover, the metallothionein-1 (MT-1) level was significantly increased in the AKI group and clinical cases revealed that iron and MT-1 levels in urine were significantly higher in patients with AKI than in those without AKI. To explore the mechanism of PMB induced ferroptosis, we silenced p53 in human kidney-2 (HK2) cells according to RNA sequencing, which showed that p53 was obviously enhanced in the PMB treated group. While PMB significantly enhanced Fe²⁺, lipid peroxidation, malondialdehyde (MDA), transferrin receptor protein 1 (TFR1), and arachidonate 12-lpoxygenase (ALOX12), decreased the survival rate, solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), and glutathione (GSH), downregulation of p53 reversed these effects, suggesting PMB induced ferroptosis by activating p53. Studies have shown p53 can promote ferroptosis by regulating the downstream factors SLC7A11 or TFR1. Further, we verified that silencing TFR1 expression as well as overexpression of SLC7A11 inhibited ferroptosis and significantly increased the survival rate of HK2 cells. Overall, PMB induces ferroptosis in renal tubular cells by activating p53 to reduce SLC7A11 expression and elevate TFR1, leading to AKI; MT-1 and iron levels in urine were significantly increased when PMB induced ferroptosis.

Natural Flavonoids and Ferroptosis: Potential Therapeutic Opportunities for Human Diseases

Flavonoids are a class of bioactive phytochemicals containing a core 2-phenylchromone skeleton and are widely found in fruits, vegetables, and herbs. Such natural compounds have gained significant attention due to their various health benefits. Ferroptosis is a recently discovered unique iron-dependent mode of cell death. Unlike traditional regulated cell death (RCD), ferroptosis is associated with excessive lipid peroxidation on cellular membranes. Accumulating evidence suggests that this form of RCD is involved in a variety of physiological and pathological processes. Notably, multiple flavonoids have been shown to be effective in preventing and treating diverse human diseases by regulating ferroptosis. In this review, we introduce the key molecular mechanisms of ferroptosis, including iron metabolism, lipid metabolism, and several major antioxidant systems. Additionally, we summarize the promising flavonoids targeting ferroptosis, which provides novel ideas for the management of diseases such as cancer, acute liver injury, neurodegenerative diseases, and ischemia/reperfusion (I/R) injury.

Gut microbiota and host cytochrome P450 characteristics in the pseudo germ-free model: co-contributors to a diverse metabolic landscape

BACKGROUND

The pseudo germ-free (PGF) model has been widely used to research the role of intestinal microbiota in drug metabolism and efficacy, while the modelling methods and the utilization of the PGF model are still not standardized and unified. A comprehensive and systematic research of the PGF model on the composition and function of the intestinal microbiota, changes in host cytochrome P450 (CYP450) enzymes expression and intestinal mucosal permeability in four different modelling cycles of the PGF groups are provided in this paper.

RESULTS

16S rRNA gene amplicon sequencing was employed to compare and analyze the alpha and beta diversity, taxonomic composition, taxonomic indicators and predicted function of gut microbiota in the control and PGF groups. Bacterial richness and diversity decreased significantly in the PGF group beginning after the first week of establishment of the PGF model with antibiotic exposure. The PGF group exposed to antibiotics for 4-week-modelling possessed the fewest indicator genera. Moreover, increased intestinal mucosal permeability occurred in the second week of PGF model establishment, indicating that one week of antibiotic exposure is an appropriate time to establish the PGF model. The results of immunoblots revealed that CYP1A2, CYP2C19 and CYP2E1 expression was significantly upregulated in the PGF group compared with the control group, implying that the metabolic clearance of related drugs would change accordingly. The abundance of functional pathways predicted in the gut microbiota changed dramatically between the control and PGF groups.

CONCLUSIONS

This study provides information concerning the microbial and CYP450 enzyme expression profiles as a reference for evaluating drug metabolism differences co-affected by gut microbiota and host CYP450 enzymes in the PGF model.

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.

The Emerging Role of Ferroptosis in Various Chronic Liver Diseases: Opportunity or Challenge

Ferroptosis is a recently identified iron-dependent form of intracellular lipid peroxide accumulation-mediated cell death. Different from other types of cell death mechanisms, it exhibits distinct biological and morphological features characterized by the loss of lipid peroxidase repair activity caused by glutathione peroxidase 4, the presence of redox-active iron, and the oxidation of phospholipids-containing polyunsaturated fatty acids. In recent years, studies have shown that ferroptosis plays a key role in various liver diseases such as alcoholic liver injury, non-alcoholic steatohepatitis, liver cirrhosis, and liver cancer. However, the mechanism of ferroptosis and its regulation on chronic liver disease are controversial among different types of cells in the liver. Herein, we summarize the current studies on mechanism of ferroptosis in chronic liver disease, aiming to outline the blueprint of ferroptosis as an effective option for chronic liver disease therapy.

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.