USP22 Protects Against Myocardial Ischemia-Reperfusion Injury via the SIRT1-p53/SLC7A11-Dependent Inhibition of Ferroptosis-Induced Cardiomyocyte Death

Tectorigenin mitigates homocysteine-induced inflammation and ferroptosis in BV-2 microglial cells through promoting the SIRT1/SLC7A11 pathway

Ferroptosis and inflammation are central to the pathophysiology of hyperhomocysteinemia (HHcy)-associated neurological disorders. Tectorigenin, a natural flavonoid aglycone extracted from numerous plants, possesses antioxidant, anti-inflammatory, and neuroprotective properties. This study aimed to investigate whether tectorigenin mitigates elevated homocysteine (Hcy)-induced toxicity in BV-2 microglial cells, focusing on its effects on inflammation and ferroptosis. Cell viability, lactate dehydrogenase (LDH) release, and proliferation assays were employed to evaluate cell injury. Inflammatory cytokines levels were determined by ELISA. Ferroptosis markers, including reactive oxygen species (ROS), lipid ROS, malondialdehyde (MDA), 4-hydroxy-nonenal (4-HNE), mitochondrial membrane potential (MMP), ATP, Fe2 + content, antioxidant enzymes (superoxide dismutase [SOD] and catalase [CAT]) activities were evaluated. mRNA and protein expressions were analyzed by qRT-PCR and western blotting, respectively. Our findings revealed that tectorigenin pretreatment significantly alleviated Hcy-induced cell injury and inflammatory response in BV-2 microglial cells. Furthermore, tectorigenin pretreatment reduced lipid peroxidation, enhanced antioxidant capacity, and alleviated ferroptotic cell death in Hcy-treated cells. Importantly, ferroptosis inhibitor Fer-1 also alleviated Hcy-induced cell injury and inflammation. Mechanistically, tectorigenin pretreatment activated the SIRT1/SLC7A11 pathway, and silencing SIRT1 reversed its protective effects. Collectively, these results indicate that tectorigenin attenuates Hcy-induced microglial injury by inhibiting inflammation and ferroptosis through the activation of the SIRT1/SLC7A11 pathway.

USP22 enhances atherosclerotic plaque stability and macrophage efferocytosis by stabilizing PPARγ

Atherosclerosis is a chronic inflammatory disease that strongly threatens human health, and macrophages play a pivotal role in its pathogenesis. Ubiquitin-specific peptidase 22 (USP22) is involved in the regulation of macrophage inflammation. However, its role in the atherosclerotic microenvironment remains unclear. In this study, we found that USP22 overexpression in macrophages alleviated atherosclerosis progression in ApoE-/- mice. In vitro, USP22 silencing enhanced macrophage inflammation and foam cell formation, and macrophage efferocytosis was significantly impaired. Mechanistically, USP22 bound to peroxisome proliferator-activated receptor γ (PPARγ) and inhibited its ubiquitination, thereby stabilizing PPARγ and promoting efferocytosis. In addition, intraperitoneal injection of the USP22 inhibitor USP22i-S02 exacerbated atherosclerosis in ApoE-/- mice. In summary, these findings indicate that USP22 may be a potential therapeutic target for the treatment of atherosclerosis.

Bergenin Alleviates Myocardial Ischemia/Reperfusion Injury via Regulating SIRT1 Through Ferroptosis

Objective

This study aimed to investigate the protective effect of bergenin on myocardial ischemia/reperfusion (I/R) injury and to elucidate its underlying mechanism.

Methods

The in vivo model of myocardial I/R injury was established by transient ligation of the left anterior descending coronary artery in Sprague-Dawley rats, which were divided into sham, I/R, I/R+bergenin, and I/R+bergenin+erastin (an agonist of ferroptosis) groups.After the model was established, the rats underwent echocardiography to assess the cardiac function. Hematoxylin and eosin (HE) staining and Masson's trichrome staining were performed to evaluate the cardiac pathological damage. Malondialdehyde (MDA), reactive oxygen species (ROS), glutathione (GSH) and iron levels were measured to determine the ferroptosis level. Western blotting was used to detect the expression of related proteins. Next, H9C2 cells were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) to mimic the in vitro model of myocardial I/R injury. EX527, a SIRT1 inhibitor, was used to further explore the role of SIRT1 in the myocardial protection of bergenin. In this part of the experiment, H9C2 cells were divided into four groups: control, OGD/R, OGD/R+bergenin, and OGD/R+bergenin+EX527.

Results

In vivo experiments, we found that the I/R group showed obvious myocardial pathological damage, oxidative stress and ferroptosis, while the bergenin pretreatment group reversed the above myocardial injury, but this protective effect was inhibited by the ferroptosis inducer erastin. In vitro experiments, compared with the OGD/R group, the bergenin group reduced the oxidative stress level, mitochondrial dysfunction and ferroptosis of H9C2 cells. We found that the protective effect of bergenin on the myocardium was abrogated by EX527. Moreover, Western blotting showed that bergenin activated SIRT1, and increased the phosphorylation of AMPK and the expression level of PGC-1α.

Conclusion

Bergenin exerted a protective effect on the myocardium by modulating the ferroptosis process during myocardial I/R injury through the SIRT1/AMPK/PGC-1α pathway.

CIAPIN1 attenuates ferroptosis via regulating PI3K/AKT pathway in LPS-induced podocytes

OBJECTIVE

Cytokine-induced apoptosis inhibitor 1 (CIAPIN1) is a crucial anti-apoptotic protein; however, its role and associated molecular pathways in ferroptosis remain largely unexplored. This study aimed to investigate the effects of CIAPIN1 on ferroptosis in lipopolysaccharide (LPS)-induced podocytes and the associated underlying phenomenon.

METHODS

In this study, we recruited 50 sepsis patients (aged 56.63 ± 10.33) with acute kidney injury (AKI), 50 sepsis patients without AKI, and 50 healthy controls. We established an in vitro model of LPS-induced MPC5 podocytes. RT-qPCR and Western blotting were used to evaluate mRNA and protein expression, respectively.

RESULTS

Serum CIAPIN1 is downregulated in patients with septic AKI and LPS-induced podocytes. CIAPIN1 overexpression (OE-CIAPIN1) attenuated cell proliferation and apoptosis in LPS-induced podocytes. OE-CIAPIN1 elevated phosphorylated phosphoinositide 3-kinase (p-PI3K; p85, Tyr458) and phosphorylated protein kinase B (p-Akt; Ser473) levels in LPS-induced podocytes. OE-CIAPIN1 significantly elevated synaptopodin mRNA levels and remarkably lowered desmin mRNA expression in MPC5 cells. In contrast, treatment with the PI3K/Akt pathway inhibitor, LY294002, reversed synaptopodin and desmin mRNA expression in MPC5 cells. Additionally, OE-CIAPIN1 reduced the malondialdehyde (MDA) content and Fe2 + concentration in the lysate of MPC5 cells, while elevating the MDA content and Fe2 + concentration by LY294002 treatment. Furthermore, OE-CIAPIN1 increased ferroptosis-related proteins, including solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4), in MPC5 cells, which was reversed by LY294002 treatment.

CONCLUSION

These results suggest that serum CIAPIN1 inhibits LPS-induced ferroptosis in podocytes by regulating the PI3K/AKT signaling pathway.

Natural products and ferroptosis: A novel approach for heart failure management

BACKGROUND

The discovery of ferroptosis has brought a revolutionary breakthrough in heart failure treatment, and natural products, as a significant source of drug discovery, are gradually demonstrating their extraordinary potential in regulating ferroptosis and alleviating heart failure symptoms. In addition to chemically synthesized small molecule compounds, natural products have attracted attention as an important source for discovering compounds that target ferroptosis in treating heart failure.

PURPOSE

Systematically summarize and analyze the research progress on improving heart failure through natural products' modulation of the ferroptosis pathway.

METHODS

By comprehensively searching authoritative databases like PubMed, Web of Science, and China National Knowledge Infrastructure with keywords such as "heart failure", "cardiovascular disease", "heart disease", "ferroptosis", "natural products", "active compounds", "traditional Chinese medicine formulas", "traditional Chinese medicine", and "acupuncture", we aim to systematically review the mechanism of ferroptosis and its link with heart failure. We also want to explore natural small-molecule compounds, traditional Chinese medicine formulas, and acupuncture therapies that can inhibit ferroptosis to improve heart failure.

RESULTS

In this review, we not only trace the evolution of the concept of ferroptosis and clearly distinguish it from other forms of cell death but also establish a comprehensive theoretical framework encompassing core mechanisms such as iron overload and system xc-/GSH/GPX4 imbalance, along with multiple auxiliary pathways. On this basis, we innovatively link ferroptosis with various types of heart failure, covering classic heart failure types and extending our research to pre-heart failure conditions such as arrhythmia and aortic aneurysm, providing new insights for early intervention in heart failure. Importantly, this article systematically integrates multiple strategies of natural products for interfering with ferroptosis, ranging from monomeric compounds and bioactive components to crude extracts and further to traditional Chinese medicine formulae. In addition, non-pharmacological means such as acupuncture are also included.

CONCLUSION

This study fills the gap in the systematic description of the relationship between ferroptosis and heart failure and the therapeutic strategies of natural products, aiming to provide patients with more diverse treatment options and promote the development of the heart failure treatment field.

Mechanisms and preventive measures of ALDH2 in ischemia‑reperfusion injury: Ferroptosis as a novel target (Review)

Ischemia‑reperfusion injury (IRI) refers to tissue or organ damage that occurs following a period of inadequate blood supply (ischemia) followed by restoration of blood flow (reperfusion) within a short time frame. This phenomenon is prevalent in clinical conditions such as cardiovascular and cerebrovascular disease, organ transplantation and stroke. Despite its frequency, effective therapeutic strategies to mitigate IRI remain elusive in clinical practice, underscoring the need for a deeper understanding of its molecular mechanisms. Aldehyde dehydrogenase 2 (ALDH2), a key enzyme in alcohol metabolism, serves a role in alleviating oxidative stress and cell damage during IRI by modulating oxidative stress, decreasing apoptosis and inhibiting inflammatory responses. ALDH2 exerts protective effects by detoxifying reactive aldehydes, thereby preventing lipid peroxidation and maintaining cellular homeostasis. Furthermore, ferroptosis, a regulated form of cell death driven by iron accumulation and subsequent lipid peroxidation, is a key process in IRI. However, the precise role of ALDH2 in modulating ferroptosis during IRI remains incompletely understood. Although there is an interaction between ALDH2 activity and ferroptosis, the underlying mechanisms have yet to be clarified. The present review examines the role of ALDH2 and ferroptosis in IRI and the potential regulatory influence of ALDH2 on ferroptosis mechanisms, as well as potential targeting of ALDH2 and ferroptosis for IRI treatment and prevention. By elucidating the complex interplay between ALDH2 and ferroptosis, the present review aims to provide new insights for the development of innovative therapeutic strategies to mitigate ischemic tissue damage and improve clinical outcomes.

The link between ferroptosis and autophagy in myocardial ischemia/reperfusion injury: new directions for therapy

Myocardial ischemia/reperfusion (I/R)-induced cell death, such as autophagy and ferroptosis, is a major contributor to cardiac injury. Regulating cell death may be key to mitigating myocardial ischemia/reperfusion injury (MI/RI). Autophagy is a crucial physiological process involving cellular self-digestion and compensation, responsible for degrading excess or malfunctioning long-lived proteins and organelles. During MI/RI, autophagy plays both "survival" and "death" roles. A growing body of research indicates that ferroptosis is a type of autophagy-dependent cell death. This article provides a comprehensive review of the functions of autophagy and ferroptosis in MI/RI, as well as the molecules mediating their interaction. Understanding the link between autophagy and ferroptosis may offer new therapeutic directions for MI/RI, bearing significant clinical implications.

Mitigating Diabetic Cardiomyopathy: The Synergistic Potential of Sea Buckthorn and Metformin Explored via Bioinformatics and Chemoinformatics

Diabetic cardiomyopathy (DCM), a critical complication of type 2 diabetes mellitus (T2DM), is marked by metabolic dysfunction, oxidative stress, and chronic inflammation, ultimately progressing to heart failure. This study investigated the synergistic therapeutic potential of Hippophae rhamnoides L. (sea buckthorn, SBU) extract and metformin in a mouse model of T2DM-induced DCM. T2DM was induced using a 45% high-fat-AGEs-enriched diet, followed by treatment with SBU, metformin, or their combination. Treatment effects were monitored through bioinformatic analysis, chemoinformatic prediction, behavioral testing, biochemical assays, histopathological evaluations and gene expression profiles. Based on bioinformatic analysis, we identified key hub genes involved in the diabetic cardiomyopathy including SERPINE1, NRG1, MYH11, PTH, NR4A2, NRF2, PGC1α, GPX4, ATF1, ASCL2, NOX1, NLRP3, CCK8, COX2, CCL2, PTGS2, EGFR, and oncostatin, which are pivotal in modulating the ferroptosis pathway. Furthermore, the expression of long non-coding RNAs (lncRNAs) NEAT1 and MALAT1, critical regulators of inflammation and cell death, was effectively downregulated, correlating with decreased levels of the pro-inflammatory marker oncostatin. The combined therapy significantly improved glucose regulation, reduced systemic inflammation and protected the heart from oxidative damage. Histopathological analysis revealed notable reductions in cardiac necrosis and fibrosis. Particularly, the combination therapy of SBU and metformin demonstrated a synergistic effect, surpassing the benefits of individual treatments in preventing cardiac damage. These findings highlight the potential of integrating SBU with metformin as a novel therapeutic strategy for managing DCM by targeting both metabolic and ferroptosis-related pathways. This dual intervention opens promising avenues for future clinical applications in diabetic heart disease management, offering a comprehensive approach to mitigating the progression of DCM.

Potential of Polydatin Against Ischemia-Reperfusion Injury: New Insights from Pharmacological-Pathological Mechanism Associations

Ischemia-reperfusion injury is a multi-tissue/organ susceptible and highly destructive disease. The complex pathological mechanisms of ischemia-reperfusion injury make its prevention and treatment highly challenging, and the development of novel drugs with pharmacological pleiotropy that can target multiple pathological mechanisms has become the focus of current drug research. Polydatin is a traditional Chinese medicine monomer with pleiotropic pharmacological effects, and existing research evidence suggests that polydatin has strong protective potential against ischemia-reperfusion injury. However, the mechanism of polydatin against ischemia-reperfusion injury is still unclear. In this review, the extensive pharmacological-pathological mechanism associations between polydatin and ischemia-reperfusion injury have been described from the perspectives of inflammatory response, oxidative stress, apoptosis, autophagy, ferroptosis, and cellular pyroptosis, which will provide references to the basic and applied research of polydatin in the field of ischemia-reperfusion injury.

Potential role of SIRT1 in cell ferroptosis

Ferroptosis is a novel form of cell death that uniquely requires iron and is characterized by iron accumulation, the generation of free radicals leading to oxidative stress, and the formation of lipid peroxides, which distinguish it from other forms of cell death. The regulation of ferroptosis is extremely complex and is closely associated with a spectrum of diseases. Sirtuin 1 (SIRT1), a NAD + -dependent histone deacetylase, has emerged as a pivotal epigenetic regulator with the potential to regulate ferroptosis through a wide array of genes intricately associated with lipid metabolism, iron homeostasis, glutathione biosynthesis, and redox homeostasis. This review provides a comprehensive overview of the specific mechanisms by which SIRT1 regulates ferroptosis and explores its potential therapeutic value in the context of multiple disease pathologies, highlighting the significance of SIRT1-mediated ferroptosis in treatment strategies.

Different types of cell death and their interactions in myocardial ischemia-reperfusion injury

Myocardial ischemia-reperfusion (I/R) injury is a multifaceted process observed in patients with coronary artery disease when blood flow is restored to the heart tissue following ischemia-induced damage. Cardiomyocyte cell death, particularly through apoptosis, necroptosis, autophagy, pyroptosis, and ferroptosis, is pivotal in myocardial I/R injury. Preventing cell death during the process of I/R is vital for improving ischemic cardiomyopathy. These multiple forms of cell death can occur simultaneously, interact with each other, and contribute to the complexity of myocardial I/R injury. In this review, we aim to provide a comprehensive summary of the key molecular mechanisms and regulatory patterns involved in these five types of cell death in myocardial I/R injury. We will also discuss the crosstalk and intricate interactions among these mechanisms, highlighting the interplay between different types of cell death. Furthermore, we will explore specific molecules or targets that participate in different cell death pathways and elucidate their mechanisms of action. It is important to note that manipulating the molecules or targets involved in distinct cell death processes may have a significant impact on reducing myocardial I/R injury. By enhancing researchers' understanding of the mechanisms and interactions among different types of cell death in myocardial I/R injury, this review aims to pave the way for the development of novel interventions for cardio-protection in patients affected by myocardial I/R injury.

Angiotensin type 1 and type 2 receptors-induced mitochondrial dysfunction promotes ferroptosis in cardiomyocytes

Previous studies suggest that ferroptosis is involved in cardiovascular diseases. The aim of the present study is to investigate the causal relationship between angiotensin II type 1 and type 2 receptors (AT1/2R) activities and mitochondrial dysfunction in induction of cardiomyocyte ferroptosis. Human AC16 cardiomyocytes were first pre-treated with an AT1/2R blockers, before stimulated with angiotensin II (Ang II) for 24 h. The redox status of the cardiomyocytes were assessed by measuring the cellular malondialdehyde (MDA), superoxide dismutase (SOD), and Nicotinamide-adenine dinucleotide phosphate, (NADPH) levels using biochemical methods. Mitochondrial reactive oxygen specifics (mitROS), mitochondrial memebrane potential, and Fe2+ levels were determined using flow cytometry. The signaling pathways, including the glutathione peroxidase 4 (GPX4), heme oxygenase-1 (HO-1), sirtuin1, and ferroptosis suppressor protein 1 (FSP1)-coenzyme Q10 (CoQ10) pathways, were evaluated using western blotting. Our results demonstrated that Ang II significantly elevated the levels of MDA, Fe2+, mitoROS, and FtMt and markedly reduced SOD, NADPH, mitochondrial membrane potential, GPX4, HO-1, Sirt1, SFXN1, Nrf2, and FSP1 levels in cardiomyocyte, which were reversed by blockade of AT1/2R. Our results suggest that AT1/2R signaling can induce myocardial ferroptosis by impairing mitochondrial function via multiple signaling pathways, including the cyst (e)ine /GSH/GPX4 axis and FSP1/coenzyme Q10 (CoQ10) axis.

In vivo and in vitro investigations of schisandrin B against angiotensin II induced ferroptosis and atrial fibrosis by regulation of the SIRT1 pathway

Schisandrin B (Sch B) derived from Schisandra chinensis, is known for its anti-inflammatory and anti-microbial properties. The study aimed to explore Sch B's protective roles and underlying mechanisms in angiotensin II (Ang II) - induced ferroptosis, atrial fibrosis, and AF using both in vivo and in vitro models. AF mice model generated induced by Ang II and established an in vitro model using the HL-1 cell line induced by Ang II. We assessed atrial fibrosis through histological analysis and oxidative stress analysis. We employed RT-qPCR and Western blot techniques to evaluate mRNA and protein expression. Sch B significantly attenuated Ang II-induced AF development, atrial apoptosis, and myocardial injury-related molecules, including CK-MB and LDH. Relative DHE intensity, MDA, NOX2, and NOX4 increased significantly, and SOD and CAT levels decreased markedly in Ang II-induced mice. Sch B treatment could inhibit atrial ROS production and oxidative stress in Ang II-infused mice. In addition, Sch B showed cardioprotective effects in Ang II-infused HL-1 cells. Sch B significantly reduced pro-inflammatory cytokines, including IL-1β, TNF-α, and IL-6, restored by EX527 (SIRT1 inhibitor). Sch B inhibited intracellular ROS generation and oxidative stress in HL-1 cells, which were restored by Ex-527. Furthermore, Sch B decreased the increase in Fe2 + concentration caused by Ang II infusion, which was recovered by Ex-527. Sch B markedly increased the expression of SIRT1, SLC7A11, GPX4 and FTH1 while reducing the expression patterns by Ex-527 treatment. Our experimental data suggest that Sch B protects against Ang II-induced ferroptosis, atrial fibrosis, and AF by activating SIRT1 in vivo and in vitro.

Inhibition of SCFKDM2A/USP22-dependent nuclear β-catenin ubiquitylation mediates cerebral ischemic tolerance

Hypoxic postconditioning (HPC) was reported to stabilize nuclear β-catenin by inhibiting lysine (K)-specific demethylase 2 A (KDM2A) in hippocampal CA1 against transient global cerebral ischemia (tGCI). Herein we investigate how HPC inhibits the K48-linked poly-ubiquitination (K48-Ub)-related degradation of nuclear β-catenin in CA1 after tGCI. We confirmed that SCFKDM2A complex targets nuclear β-catenin for degradation via ubiquitin proteasome pathway in vitro. HPC reduced SCFKDM2A complex and the K48-Ub of β-catenin, and increased ubiquitin-specific peptidase 22 (USP22) in nucleus after tGCI. Furthermore, KDM2A knockdown decreased the K48-Ub of nuclear β-catenin and nuclear β-catenin-SCFKDM2A complex interaction after tGCI. Moreover, β-catenin knockdown suppressed nuclear survivin expression and attenuated neuroprotection induced by HPC. In contrast, the overexpression of USP22 promoted nuclear β-catenin deubiquitination and enhanced the neuroprotective effects offered by HPC. Taken together, this study supports that HPC downregulated the K48-Ub of nuclear β-catenin through suppressing SCFKDM2A and increasing USP22, thereby inducing cerebral ischemic tolerance.

The Role of P53 in Myocardial Ischemia-Reperfusion Injury

PURPOSE

P53 is one of the key tumor suppressors. In normal cells, p53 is maintained at low levels by the ubiquitination of the ubiquitinated ligase MDM2. In contrast, under stress conditions such as DNA damage and ischemia, the interaction between p53 and MDM2 is blocked and activated by phosphorylation and acetylation, thereby mediating the trans-activation of p53 through its target genes to regulate a variety of cellular responses. Previous studies have shown that the expression of p53 is negligible in normal myocardium, tends to increase in myocardial ischemia and is maximally induced in ischemia-reperfused myocardium, demonstrating a possible key role of p53 in the development of MIRI. In this review, we detail and summarize recent studies on the mechanism of action of p53 in MIRI and describe the therapeutic agents targeting the relevant targets to provide new strategies for the prevention and treatment of MIRI.

METHODS

We collected 161 relevant papers mainly from Pubmed and Web of Science (search terms "p53" and "myocardial ischemia-reperfusion injury"). After that, we selected pathway studies related to p53 and classified them according to their contents. We eventually analyzed and summarized them.

RESULTS AND CONCLUSION

In this review, we detail and summarize recent studies on the mechanism of action of p53 in MIRI and validate its status as an important intermediate affecting MIRI. On the one hand, p53 is regulated and modified by multiple factors, especially non-coding RNAs; on the other hand, p53 regulates apoptosis, programmed necrosis, autophagy, iron death and oxidative stress in MIRI through multiple pathways. More importantly, several studies have reported medications targeting p53-related therapeutic targets. These medications are expected to be effective options for the alleviation of MIRI, but further safety and clinical studies are needed to convert them into clinical applications.

The lactate metabolism and protein lactylation in epilepsy

Protein lactylation is a new form of post-translational modification that has recently been proposed. Lactoyl groups, derived mainly from the glycolytic product lactate, have been linked to protein lactylation in brain tissue, which has been shown to correlate with increased neuronal excitability. Ischemic stroke may promote neuronal glycolysis, leading to lactate accumulation in brain tissue. This accumulation of lactate accumulation may heighten neuronal excitability by upregulating protein lactylation levels, potentially triggering post-stroke epilepsy. Although current clinical treatments for seizures have advanced significantly, approximately 30% of patients with epilepsy remain unresponsive to medication, and the prevalence of epilepsy continues to rise. This study explores the mechanisms of epilepsy-associated neuronal death mediated by lactate metabolism and protein lactylation. This study also examines the potential for histone deacetylase inhibitors to alleviate seizures by modifying lactylation levels, thereby offering fresh perspectives for future research into the pathogenesis and clinical treatment of epilepsy.

Danshen injection ameliorates unilateral ureteral obstruction-induced renal fibrosis by inhibiting ferroptosis via activating SIRT1/GPX4 pathway

Introduction

The pathogenesis of renal fibrosis is related to blood stasis, and the method of promoting blood circulation and removing blood stasis is often used as the treatment principle. Danshen injection (DSI) is a commonly used drug for promoting blood circulation and removing blood stasis in clinic. However, whether DSI slows the progression of renal fibrosis or the potential mechanism is uncertain.

Methods

We investigated renal fibrosis models using UUO mice and TGF-β stimulation in HK-2 cells.

Results

Our findings revealed that DSI or Fer-1 alleviated kidney injury by ameliorating renal morphology injury and pathological injury in vivo. Besides, DSI or Fer-1 inhibited renal fibrosis in vivo and in TGF-β-induced HK-2 cells. Furthermore, ferroptosis was lessened under DSI or Fer-1 treatment. More importantly, the DSI active ingredients (danshensu, salvianolic acid B, protocatechuic aldehyde, caffeic acid and tanshinone IIA) could bind to SIRT1. The protein levels of SIRT1 and GPX4 were downregulated accompanied by the incremental concentrations of TGF-β or Erastin, which were repaired by DSI or Fer-1 intervention. However, the inhibition of ferroptosis and renal fibrosis owing to DSI were reversed by SIRT1 inhibitor EX527.

Conclusion

Taken together, our results indicated that DSI could protect against ferroptosis to attenuate renal fibrosis by activating the SIRT1/GPX4 pathway. It is expected to be a potential agent to treat renal fibrosis.

Epigenetic regulation and post-translational modifications of ferroptosis-related factors in cardiovascular diseases

As an important element of the human body, iron participates in numerous physiological and biochemical reactions. In the past decade, ferroptosis (a form of iron-dependent regulated cell death) has been reported to contribute to the pathogenesis and progression of various diseases. The stability of iron in cardiomyocytes is crucial for the maintenance of normal physiological cardiac activity. Ferroptosis has been detected in many cardiovascular diseases (CVDs), including coronary heart disease, myocardial ischemia-reperfusion injury, heart failure, and chemotherapy-induced myocardial damage. In cardiomyocytes, epigenetic regulation and post-translational modifications regulate the expression of ferroptosis-related factors, maintain iron homeostasis, and participate in the progression of CVDs. Currently, there is no detailed mechanism to explain the relationship between epigenetic regulation and ferroptosis in CVDs. In this review, we provide an initial summary of the core mechanisms of ferroptosis in cardiomyocytes, with first focus on the epigenetic regulation and expression of ferroptosis-related factors in the context of common cardiovascular diseases. We anticipate that the new insights into the pathogenesis of CVDs provided here will inspire the development of clinical interventions to specifically target the active sites of these factors, reducing the harmfulness of ferroptosis to human health.

Ferroptosis and its impact on common diseases

Ferroptosis is a novel form of programmed cell death characterized by iron accumulation, lipid peroxidation, and a decline in antioxidant capacity, all of which are regulated by gene expression. The onset of numerous diseases is closely associated with ferroptosis. Common diseases affect a large population, reduce the quality of life, and impose an increased burden on the healthcare system. The role of ferroptosis in common diseases, its therapeutic potential, and even its translation into clinical drug treatments are currently significant research topics worldwide. This study preliminarily explores the theoretical basis of ferroptosis, its mechanism and treatment prospect in common diseases including ischaemia-reperfusion injury, inflammatory bowel diseases, liver fibrosis, acute kidney injury, diabetic kidney disease, stroke, Alzheimer's disease, cardiovascular disease, immune and cancer. This review provides a theoretical foundation for the further study and development of ferroptosis, as well as for the prevention and treatment of common diseases.

Mechanisms and Therapeutic Potential of Multiple Forms of Cell Death in Myocardial Ischemia-Reperfusion Injury

Programmed cell death, especially programmed necrosis such as necroptosis, ferroptosis, and pyroptosis, has attracted significant attention recently. Traditionally, necrosis was thought to occur accidentally without signaling pathways, but recent discoveries have revealed that molecular pathways regulate certain forms of necrosis, similar to apoptosis. Accumulating evidence indicates that programmed necrosis is involved in the development of various diseases, including myocardial ischemia-reperfusion injury (MIRI). MIRI occurs when blood flow and oxygen return to an ischemic area, causing excessive production of reactive oxygen species. While this reperfusion is critical for treating myocardial infarction, it inevitably causes cellular damage via oxidative stress. Furthermore, this cellular damage triggers multiple forms of cardiomyocyte death, which is the primary cause of inflammation, cardiac tissue remodeling, and ensuing heart failure. Therefore, understanding the molecular mechanisms of various forms of cell death in MIRI is crucial for therapeutic target discovery. Developing therapeutic strategies to inhibit multiple cell death pathways simultaneously could provide effective protection against MIRI. In this paper, we review the fundamental molecular pathways and MIRI-specific mechanisms of apoptosis, necroptosis, ferroptosis, and pyroptosis. Additionally, we suggest that the simultaneous suppression of multiple cell death pathways could be an effective therapy and identify potential therapeutic targets for implementing this strategy.

Deciphering ferroptosis in critical care: mechanisms, consequences, and therapeutic opportunities

Ischemia-reperfusion injuries (IRI) across various organs and tissues, along with sepsis, significantly contribute to the progression of critical illnesses. These conditions disrupt the balance of inflammatory mediators and signaling pathways, resulting in impaired physiological functions in human tissues and organs. Ferroptosis, a distinct form of programmed cell death, plays a pivotal role in regulating tissue damage and modulating inflammatory responses, thereby influencing the onset and progression of severe illnesses. Recent studies highlight that pharmacological agents targeting ferroptosis-related proteins can effectively mitigate oxidative stress caused by IRI in multiple organs, alleviating associated symptoms. This manuscript delves into the mechanisms and signaling pathways underlying ferroptosis, its role in critical illnesses, and its therapeutic potential in mitigating disease progression. We aim to offer a novel perspective for advancing clinical treatments for critical illnesses.

The Emerging Roles of Hydrogen Sulfide in Ferroptosis

Significance: Ferroptosis, a form of regulated cell death characterized by a large amount of lipid peroxidation-mediated membrane damage, joins the evolution of multisystem diseases, for instance, neurodegenerative diseases, chronic obstructive pulmonary disease, acute respiratory distress syndrome, osteoporosis, osteoarthritis, and so forth. Since being identified as the third gasotransmitter in living organisms, the intricate role of hydrogen sulfide (H2S) in ferroptosis has emerged at the forefront of research. Recent Advances: Novel targets in the relevant metabolic pathways have been found, including transferrin receptor 1, cystine/glutamate antiporter, and others, coupled with the exploration of new signaling pathways, particularly the p53 signaling pathway, the nitric oxide/nuclear factor erythroid 2-related factor 2 signaling pathway, and so on. Many diseases such as emphysema and airway inflammation, myocardial diseases, endothelial dysfunction in aging arteries, and traumatic brain injury have recently been found to be alleviated directly by H2S inhibition of ferroptosis. Safe, effective, and tolerable novel H2S donors have been developed and have shown promising results in phase I clinical trials. Critical Issues: Complicated cross talk between the ferroptosis signaling pathway and oncogenic factors results in the risk of cancer when inhibiting ferroptosis. Notably, targeted delivery of H2S is still a challenging task. Future Directions: Discovering more reliable and stable novel H2S donors and achieving their targeted delivery will enable further clinical trials for diseases associated with ferroptosis inhibition by H2S, determining their safety, efficacy, and tolerance. Antioxid. Redox Signal. 41, 1150-1172.

Inhibition of Sat1 alleviates myocardial ischemia-reperfusion injury through regulation of ferroptosis via MAPK/ERK pathway

Introduction

Myocardial ischemia-reperfusion injury (MIRI) is a prevalent complication in patients with myocardial infarction. The pathological mechanism of MIRI remains elusive. Ferroptosis plays a critical role in MIRI. This study aimed to investigate the role of spermidine/spermine N1-acetyltransferase 1 (Sat1) in MIRI by regulation of ferroptosis.

Methods

Rats and H9C2 cells were used to perform MIRI model. The extent of myocardial damage and associated pathological changes were evaluated. Protein expression was detected by western blot. Then we observed the mitochondrial morphology and measured cell viability and damage. The levels of lipid peroxide and glutathione were measured, and lipid reactive oxygen species (ROS) was quantified. Differentially expressed genes (DEGs) in MIRI were analyzed. Moreover, to explore the role of Sat1 in MIRI, this study utilized adeno-associated virus 9 and lentiviral transduction to modulate Sat1 expression in rats and H9C2 cells, respectively. The transcription factor that regulates Sat1 expression was predicated. Luciferase reporter gene experiment was conducted to reveal the potential sites of Sox2 binding to Sat1.

Results

This study revealed that ferroptosis was involved in MIRI. Through bioinformatic analysis, Sat1 was identified as a significant gene in MIRI, which has been reported as an inducer of ferroptosis. Our results showed that Sat1 expression was significantly increased in MIRI. Next, the study showed that inhibition of Sat1 alleviated MIRI by suppressing ferroptosis in vivo and in vitro, and over-expression of Sat1 promoted MIRI via activation of ferroptosis. Furthermore, Sat1 and its interacting genes were enriched in several signaling pathways, including ferroptosis and the MAPK signaling pathway. The results showed that Sat1 regulated MIRI through ferroptosis via MAPK/ERK pathway. Moreover, it is found that Sox2 can suppress Sat1 expression at the transcriptional level. The potential binding site was TAACAAAGGAA.

Conclusion

In sum, this study demonstrated Sat1 expression was increased in MIRI, inhibition of Sat1 can alleviate MIRI by regulating ferroptosis via MAPK/ERK pathway, and Sat1 was negatively regulated by Sox2. These findings suggested that Sat1 may serve as a potential therapeutic target for the treatment of MIRI.

Engineered Biomimetic Nanoparticles-Mediated Targeting Delivery of Allicin Against Myocardial Ischemia-Reperfusion Injury by Inhibiting Ferroptosis

Background

Cardiac microvascular damage is substantially related with the onset of myocardial ischaemia-reperfusion (IR) injury. Reportedly, allicin (AL) effectively protects the cardiac microvascular system from IR injury. However, the unsatisfactory therapeutic efficacy of current drugs and insufficient drug delivery to the damaged heart are major concerns. Here, inspired by the natural interaction between neutrophils and inflamed cardiac microvascular endothelial cells (CMECs), a neutrophil membrane-camouflaged nanoparticle for non-invasive active-targeting therapy for IR injury by improving drug delivery to the injured heart is constructed.

Methods

In this study, we engineered mesoporous silica nanoparticles (MSNs) coated with a neutrophil membrane to act as a drug delivery system, encapsulating AL. The potential of the nanoparticles (named AL@MSNs@NM) for specific targeting of infarcted myocardium was assessed using small animal vivo imaging system. The cardiac function of AL@MSNs@NM after treatment was evaluated by Animal Ultrasound Imaging system, HE staining, and Laser Speckle Imaging System. The therapeutic mechanism was analyzed by ELISA kits, immunofluorescence, and PCR.

Results

We discovered that AL@MSNs@NM significantly improves cardiac function index, reduced infarct size and fibrosis, increased vascular perfusion in ischemic areas, and also promoted the function of CMECs, including migration, tube formation, shear stress adaptation, and nitric oxide production. Further research revealed that AL@MSNs@NM have cardio-protective functions in IR rats by inhibiting CMEC ferroptosis and increasing platelet endothelial cell adhesion molecule-1 (PECAM-1) expression.

Conclusion

Our results indicated that AL@MSNs@NM significantly reversed CMEC ferroptosis and increased PECAM-1 expression, enhanced cardiac function, and reduced myocardial infarction size. Therefore, this strategy demonstrates that engineered biomimetic nanotechnology effectively delivers AL for targeted therapy of myocardial infarction.

Exosomes from Hypoxic Pretreatment ADSCs Ameliorate Cardiac Damage Post-MI via Activated circ-Stt3b/miR-15a-5p/GPX4 Signaling and Decreased Ferroptosis

Accumulation studies confirmed that oxidative stress caused by ischemia after myocardial infarction (MI) is an important cause of ventricular remodeling. Exosome secretion through hypoxic pretreatment adipose-derived mesenchymal stem cells (ADSCs) ameliorates myocardial damaging post-MI. However, if ADSCs exosome can improve the microenvironment and ameliorate cardiac damage post-MI still unknown. Next-generation sequencing (NGS) was used to study abnormally expressed circRNAs in hypoxic pretreatment ADSC exosomes (HExos) and untreated ADSC exosomes (Exos). Bioinformatics and luciferase reporting were used to elucidate interaction correlation related to circRNA, mRNA, and miRNA. HL-1 cells were used to analyze the reactive oxygen species (ROS) and apoptosis under hypoxic conditions using immunofluorescence and flow cytometry. An MI mouse model was constructed and the therapeutic effect of Exos was determined using immunohistochemistry, immunofluorescence, and ELISA. The results showed that HExos had a more pronounced treatment effect than ADSC Exos on cardiac damage amelioration after MI. NGS showed that circ-Stt3b plays a role in HExo-mediated cardiac damage repair after MI. Overexpression of circ-Stt3b decreased apoptosis, ROS level, and inflammatory factor expression in HL-1 cells under hypoxic conditions. Bioinformatics and luciferase reporting data validated miR-15a-5p and GPX4 as downstream circ-Stt3b targets. GPX4 downregulation or miR-15a-5p overexpression reversed protective effect regarding circ-Stt3b upon HL-1 cells after exposure to a hypoxic microenvironment. Overexpression of circ-Stt3b increased the treatment effect of ASDSC Exos on cardiac damage amelioration after MI. Taken together, the study results demonstrated that Exos from hypoxic pretreatment ADSCs ameliorate cardiac damage post-MI through circ-Stt3b/miR-15a-5p/GPX4 signaling activation and decreased ferroptosis.

Ubiquitin-specific protease 38 promotes atrial fibrillation in diabetic mice by stabilizing iron regulatory protein 2

BACKGROUND

Atrial fibrillation (AF) is a common cardiovascular disease often observed in diabetes mellitus, and there is currently no satisfactory therapeutic option. Ubiquitin-specific protease 38 (USP38) has been implicated in the degradation of numerous substrate proteins in the myocardium. Herein, we aim to investigate the role of USP38 in AF induced by diabetes.

METHODS

Cardiac-specific transgenic USP38 mice and cardiac-specific knockout USP38 mice were constructed, and streptozotocin was used to establish diabetic mouse model. Functional, electrophysiological, histologic, biochemical studies were performed.

RESULTS

The expression of USP38 was upregulated in atrial tissues of diabetic mice and HL-1 cells exposed to high glucose. USP38 overexpression increased susceptibility to AF, accompanied by aberrant expression of calcium-handling protein, heightened iron load and oxidation stress in diabetic mice. Conversely, USP38 deficiency reduced vulnerability to AF by hampering ferroptosis. Mechanistically, USP38 bound to iron regulatory protein 2 (IRP2), stabilizing it and remove K48-linked polyubiquitination chains, thereby increasing intracellular iron overload, lipid peroxidation, and ultimately contributing to ferroptosis. In addition, reduced iron overload by deferoxamine treatment alleviated oxidation stress and decreased vulnerability to AF in diabetic mice.

CONCLUSION

Overall, our findings reveal the detrimental role of USP38 in diabetes-related AF, manifested by increased level of iron overload and oxidation stress.

The role and possible mechanism of the ferroptosis-related SLC7A11/GSH/GPX4 pathway in myocardial ischemia-reperfusion injury

BACKGROUND

Myocardial ischemia-reperfusion injury (MI/RI) is an unavoidable risk event for acute myocardial infarction, with ferroptosis showing close involvement. We investigated the mechanism of MI/RI inducing myocardial injury by inhibiting the ferroptosis-related SLC7A11/glutathione (GSH)/glutathione peroxidase 4 (GPX4) pathway and activating mitophagy.

METHODS

A rat MI/RI model was established, with myocardial infarction area and injury assessed by TTC and H&E staining. Rat cardiomyocytes H9C2 were cultured in vitro, followed by hypoxia/reoxygenation (H/R) modeling and the ferroptosis inhibitor lipoxstatin-1 (Lip-1) treatment, or 3-Methyladenine or rapamycin treatment and overexpression plasmid (oe-SLC7A11) transfection during modeling. Cell viability and death were evaluated by CCK-8 and LDH assays. Mitochondrial morphology was observed by transmission electron microscopy. Mitochondrial membrane potential was detected by fluorescence dye JC-1. Levels of inflammatory factors, reactive oxygen species (ROS), Fe2+, malondialdehyde, lipid peroxidation, GPX4 enzyme activity, glutathione reductase, GSH and glutathione disulfide, and SLC7A11, GPX4, LC3II/I and p62 proteins were determined by ELISA kit, related indicator detection kits and Western blot.

RESULTS

The ferroptosis-related SLC7A11/GSH/GPX4 pathway was repressed in MI/RI rat myocardial tissues, inducing myocardial injury. H/R affected GSH synthesis and inhibited GPX4 enzyme activity by down-regulating SLC7A11, thus promoting ferroptosis in cardiomyocytes, which was averted by Lip-1. SLC7A11 overexpression improved H/R-induced cardiomyocyte ferroptosis via the GSH/GPX4 pathway. H/R activated mitophagy in cardiomyocytes. Mitophagy inhibition reversed H/R-induced cellular ferroptosis. Mitophagy activation partially averted SLC7A11 overexpression-improved H/R-induced cardiomyocyte ferroptosis. H/R suppressed the ferroptosis-related SLC7A11/GSH/GPX4 pathway by inducing mitophagy, leading to cardiomyocyte injury.

CONCLUSIONS

Increased ROS under H/R conditions triggered cardiomyocyte injury by inducing mitophagy to suppress the ferroptosis-related SLC7A11/GSH/GPX4 signaling pathway activation.

MiRNA Regulates Ferroptosis in Cardiovascular and Cerebrovascular Diseases

Cardiovascular and cerebrovascular diseases (CCVDs) significantly contribute to global mortality and morbidity due to their complex pathogenesis involving multiple biological processes. Ferroptosis is an important physiological process in CCVDs, manifested by an abnormal increase in intracellular iron concentration. MiRNAs, a key class of noncoding RNA molecules, are crucial in regulating CCVDs through pathways like glutathione-glutathione peroxidase 4, glutamate/cystine transport, iron metabolism, lipid metabolism, and other oxidative stress pathways. This article summarizes the progress of miRNAs' regulation on CCVDs, aiming to provide insights for the diagnosis and treatment of CCVDs.

Ferroptosis and myocardial ischemia-reperfusion: mechanistic insights and new therapeutic perspectives

Myocardial ischemia-reperfusion injury (MIRI) is a significant factor in the development of cardiac dysfunction following a myocardial infarction. Ferroptosis, a type of regulated cell death driven by iron and marked by lipid peroxidation, has garnered growing interest for its crucial involvement in the pathogenesis of MIRI.This review comprehensively examines the mechanisms of ferroptosis, focusing on its regulation through iron metabolism, lipid peroxidation, VDAC signaling, and antioxidant system dysregulation. We also compare ferroptosis with other forms of cell death to highlight its distinct characteristics. Furthermore, the involvement of ferroptosis in MIRI is examined with a focus on recent discoveries concerning ROS generation, mitochondrial impairment, autophagic processes, ER stress, and non-coding RNA regulation. Lastly, emerging therapeutic strategies that inhibit ferroptosis to mitigate MIRI are reviewed, providing new insights into potential clinical applications.

Dose-Dependent Relationship between Iron Metabolism and Perioperative Myocardial Injury in Cardiac Surgery with Cardiopulmonary Bypass: A Retrospective Analysis

INTRODUCTION

We sought to comprehensively explore the potential linear and nonlinear relationship between preoperative iron metabolism and perioperative myocardial injury (PMI) following cardiac surgery with cardiopulmonary bypass (CPB).

METHODS

Patients who underwent cardiac surgery with CPB between December 2018 and April 2021 were retrospectively collected. The measurements of iron metabolism included serum iron (SI), serum ferritin (SF), transferrin (TRF), transferrin saturation (TS), and total iron-binding capacity (TIBC). Logistic regression and restricted cubic spline (RCS) models were used for linear and nonlinear analysis. The primary outcome was PMI with a 100× upper reference limit.

RESULTS

Of 2,420 patients screened, 744 eligible patients were enrolled for the final analysis. The incidence of PMI was 25.7%. No significant linear relationship was observed. In the RCS models adjusted with age (median: 56), female, and history of diabetes, a statistically significant difference was detected between TRF (p for nonlinear 0.0152) or TIBC (p for nonlinear 0.0477) and PMI. The gentle U-shaped relationship observed between TRF, TIBC, and PMI suggests that when TRF and TIBC increase, the risk decreases, reaching its lowest point when TRF = 2.4 and TIBC = 54. Nevertheless, as TRF and TIBC continue to increase, the risk starts to rise again. Subgroup analyses yielded consistent findings, with a notable emphasis on older patients who were more susceptible to variations in iron metabolism.

CONCLUSION

Iron metabolism, including TRF, and TIBC, exhibited a nonlinear relationship with PMI by the RCS model adjusted by age, gender, and history of diabetes.

Sirtuin 1 in regulating the p53/glutathione peroxidase 4/gasdermin D axis in acute liver failure

In this editorial, we comment on the article by Zhou et al. The study reveals the connection between ferroptosis and pyroptosis and the effect of silent information regulator sirtuin 1 (SIRT1) activation in acute liver failure (ALF). ALF is characterized by a sudden and severe liver injury resulting in significant hepatocyte damage, often posing a high risk of mortality. The predominant form of hepatic cell death in ALF involves apoptosis, ferroptosis, autophagy, pyroptosis, and necroptosis. Glutathione peroxidase 4 (GPX4) inhibition sensitizes the cell to ferroptosis and triggers cell death, while Gasdermin D (GSDMD) is a mediator of pyroptosis. The study showed that ferroptosis and pyroptosis in ALF are regulated by blocking the p53/GPX4/GSDMD pathway, bridging the gap between the two processes. The inhibition of p53 elevates the levels of GPX4, reducing the levels of inflammatory and liver injury markers, ferroptotic events, and GSDMD-N protein levels. Reduced p53 expression and increased GPX4 on deletion of GSDMD indicated ferroptosis and pyroptosis interaction. SIRT1 is a NAD-dependent deacetylase, and its activation attenuates liver injury and inflammation, accompanied by reduced ferroptosis and pyroptosis-related proteins in ALF. SIRT1 activation also inhibits the p53/GPX4/GSDMD axis by inducing p53 acetylation, attenuating LPS/D-GalN-induced ALF.

Overexpression of USP22 ameliorates LPS-induced endometrial stromal cells inflammation and modulates cells decidualization by inhibiting ferroptosis

Endometritis and the failure of decidualization of the endometrium are important factors contributing to the increased incidence of abortion. USP22 is associated with various inflammatory diseases and has been shown to be involved in endometrial decidualization in mice. This study aims to investigate whether USP22 is involved in the regulation of inflammatory response and decidualization in human endometrial stromal cells (hESCs). In this study, lipopolysaccharide (LPS) was used to induce inflammation in hESCs, and MPA combined with cAMP was used to induce decidualization of hESCs. USP22 overexpression vector was constructed to study the role of USP22 in endometritis. The results showed that the USP22 protein and mRNA levels were decreased in LPS-induced hESCs. LPS induction increased the levels of TNF-α, IL-1β, and IL-6, as well as the expression of iNOS and COX2 proteins in hESCs. In the LPS group, the levels of F-actin, PRL, IGFBP1, SLC7A11, and GPX4 proteins decreased, while the levels of lipid peroxidation and total iron content increased. Additionally, the levels of ACSL4 and TFR1 proteins were up-regulated. Overexpression of USP22 reversed LPS-induced cellular inflammation, attenuated decidualization, and inhibited ferroptosis. However, the use of ferroptosis inducers diminished the regulatory effects of USP22 on inflammatory responses and decidualization. In summary, these suggested that USP22 reduces the LPS-induced inflammatory response and regulates the decidualization of hESCs, and possibly involving ferroptosis.

Phosphoglycerate Dehydrogenase Overexpression Inhibits Ferroptosis to Repress Calcification of Human Coronary Artery Vascular Smooth Muscle Cells via the P53/SLC7A11 Pathway

Background

Coronary artery calcification (CAC) is in almost all patients with coronary artery disease and requires more effective therapies. We aim to explore the effects of phosphoglycerate dehydrogenase (PHGDH) on CAC.

Methods

We identified the differentially expressed genes through bioinformatic analysis and selected PHGDH for further verification. Human coronary artery smooth muscle cells (HCASMCs) cultured with calcifying medium were used as models of CAC in vitro. Erastin was administered to induce ferroptosis. We determined the cell viability by the cell count kit-8 assay. The alkaline phosphatase activity, calcium content, and the expression of glutathione were evaluated by the corresponding detection kits. The calcification level was detected by alizarin red staining. Then we performed Western blot to examine the expression of runt-related transcription factor 2, bone morphogenetic protein 2, cyclooxygenase 2, glutathione peroxidase 4, P53, and solute carrier family 7a member 11 (SLC7A11).

Results

We acquired 201 differentially expressed genes and selected PHGDH to verify. In calcifying medium-induced HCASMCs, PHGDH overexpression increased the cell viability and decreased the alkaline phosphatase activity, calcium content, calcification level, and the expression of bone morphogenetic protein 2 and runt-related transcription factor 2. Additionally, we found higher levels of glutathione, glutathione peroxidase 4, and SLC7A11 and lower levels of cyclooxygenase 2 and P53 after up-regulating PHGDH. Erastin reversed the effects of PHGDH on calcification of HCASMCs.

Conclusion

PHGDH overexpression suppresses the calcification level of HCASMCs by inhibiting ferroptosis through the P53/SLC7A11 signaling pathway, suggesting PHGDH as a promising therapeutic target of CAC.

Schisandrin B inhibits inflammation and ferroptosis in S.aureus-induced mastitis through regulating SIRT1/p53/SLC7A11 signaling pathway

Mastitis, one of the most significant problems in women, is commonly caused by pathogens, especially Staphylococcus aureus (S.aureus). Schisandrin B (SCB), the main abundant derivatives from Schisandra chinensis, has been proven to have the ability to inhibiting inflammation and bacteria. However, few relevant researches systematically illustrate the role SCB in the treatment of mastitis. The aim of the present study is to demonstrate the mechanism that SCB functions in reducing pathological injury to the mammary gland in treating S.aureus-induced mastitis. H&E staining was used to identify pathological changes and injuries in mastitis. The levels of cytokines associated with inflammation were detected by ELISA. Key signals relevant to ferroptosis and Nrf2 signaling pathway were tested by western blot analysis and iron assay kit. Compared with the control group, inflammation-associated factors, such as IL-1β, TNF-α, MPO activity, increased significantly in S. aureus-treated mice. However, these changes were inhibited by SCB. Ferroptosis-associated factors Fe2+ and MDA increased significantly, and GSH, GPX4 and ferritin expression decreased markedly in S. aureus-treated mice. SCB treatment could attenuate S.aureus-induced ferroptosis. Furthermore, SCB increase SIRT1 and SLC7A11 expression and down-regulated p53 expression and NF-κB activation. In conclusion, SCB alleviates S.aureus-induced mastitis via up-regulating SIRT1/p53/SLC7A11 signaling pathway, attenuating the activation of inflammation-associated cytokines and ferroptosis in the mammary gland tissues.

Regulation of optimized new Shengmai powder on cardiomyocyte apoptosis and ferroptosis in ischemic heart failure rats: The mediating role of phosphatidylinositol-3-kinase/protein kinase B/tumor protein 53 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Optimized New Shengmai Powder (ONSMP) is a sophisticated traditional Chinese medicinal formula renowned for bolstering vital energy, optimizing blood circulation, and mitigating fluid retention. After years of clinical application, ONSMP has shown a significant impact in improving myocardial injury and cardiac function and has a positive effect on treating heart failure. However, many unknowns exist about the molecular biological mechanisms of how ONSMP exerts its therapeutic effects, which require further research and exploration.

AIM OF THE STUDY

Exploring the potential molecular biological mechanisms by which ONSMP ameliorates cardiomyocyte apoptosis and ferroptosis in ischemic heart failure (IHF).

MATERIALS AND METHODS

First, we constructed a rat model of IHF by inducing acute myocardial infarction through surgery and using echocardiography, organ coefficients, markers of heart failure, antioxidant markers, and histopathological examination to assess the effects of ONSMP on cardiomyocyte apoptosis and ferroptosis in IHF rats. Next, we used bioinformatics analysis techniques to analyze the active components, signaling pathways, and core targets of ONSMP and calculated the interactions between core targets and corresponding elements. Finally, we detected the positive expression of apoptosis and ferroptosis markers and core indicators of signaling pathways by immunohistochemistry; detected the mean fluorescence intensity of core indicators of signaling pathways by immunofluorescence; detected the protein expression of signaling pathways and downstream effector molecules by western blotting; and detected the mRNA levels of p53 and downstream effector molecules by quantitative polymerase chain reaction.

RESULTS

ONSMP can activate the Ser83 site of ASK by promoting the phosphorylation of the PI3K/AKT axis, thereby inhibiting the MKK3/6-p38 axis and the MKK4/7-JNK axis signaling to reduce p53 expression, and can also directly target and inhibit the activity of p53, ultimately inhibiting p53-mediated mRNA and protein increases in PUMA, SAT1, PIG3, and TFR1, as well as mRNA and protein decreases in SLC7A11, thereby inhibiting cardiomyocyte apoptosis and ferroptosis, effectively improving cardiac function and ventricular remodeling in IHF rat models.

CONCLUSION

ONSMP can inhibit cardiomyocyte apoptosis and ferroptosis through the PI3K/AKT/p53 signaling pathway, delaying the development of IHF.

Ubiquitin-specific protease 22 controls melanoma metastasis and vulnerability to ferroptosis through targeting SIRT1/PTEN/PI3K signaling

Metastasis is a major contributing factor that affects the prognosis of melanoma patients. Nevertheless, the underlying molecular mechanisms involved in melanoma metastasis are not yet entirely understood. Here, we identified ubiquitin-specific protease 22 (USP22) as a pro-oncogenic protein in melanoma through screening the survival profiles of 52 ubiquitin-specific proteases (USPs). USP22 demonstrates a strong association with poor clinical outcomes and is significantly overexpressed in melanoma. Ablation of USP22 expression remarkably attenuates melanoma migration, invasion, and epithelial-mesenchymal transition in vitro and suppresses melanoma metastasis in vivo. Mechanistically, USP22 controls melanoma metastasis through the SIRT1/PTEN/PI3K pathway. In addition, we conducted an United States Food and Drug Administration-approved drug library screening and identified topotecan as a clinically applicable USP22-targeting molecule by promoting proteasomal degradation of USP22. Finally, we found that both pharmacological and genetic silence of USP22 sensitize RSL3-induced ferroptosis through suppressing the PI3K/Akt/mTOR pathway and its downstream SCD, and ferroptosis inhibitor could partly rescued the decreased lung metastasis by topotecan in vivo. Overall, our findings reveal a prometastatic role of USP22 and identify topotecan as a potent USP22-targeting drug to limit melanoma metastasis.

Induction of ferroptosis by brucine suppresses gastric cancer progression through the p53-mediated SLCA711/ALOX12 axis

Increasing evidence indicates important antiproliferative and anti-inflammatory roles of brucine in various diseases. However, the mechanism through which brucine causes the cell death of gastric cancer (GC) remains unclear. In the current research, we looked into whether brucine inhibits GC progression. GC cell migration and proliferation were assessed in response to brucine using Transwell, scratch, and the Cell Counting Kit-8 (CCK-8) assays. To assess the expression of proteins linked to ferroptosis, western blotting was used. An in vivo experiment was conducted to investigate if brucine decreases tumor growth. The CCK-8 experiment demonstrated that brucine reduced AGS and MKN45 cell viability in a way that was dose- and time-dependent. Brucine dramatically promoted cell death in AGS and MKN45 cells according to flow cytometry. In addition, brucine reduced AGS and MKN45 cells' ability to migrate. According to Western blot investigations, brucine elevated p53 and ALOX12 expression, while suppressing the expression of SLC7A11 in AGS and MKN45 cells. Notably, silencing p53 reversed brucine-induced ferroptotic cell death. Additionally, brucine was shown to decrease tumor weight and volume in in vivo experiments. Moreover, malondialdehyde (MDA) and Fe2+ levels decreased in response to brucine treatment. Furthermore, in tumors treated with brucine, p53 and ALOX12 expression increased, whereas SLCA711 expression decreased. In summary, we demonstrated that brucine regulates the p53/SLCA711/ALOX12 axis to cause ferroptosis in GC cells. The results of this study lend support to the idea of treating GC with brucine.

Cucurbitacin B induces ferroptosis in oral leukoplakia via the SLC7A11/mitochondrial oxidative stress pathway

BACKGROUND

Oral leukoplakia (OLK), characterized by abnormal epithelial hyperplasia, is the most common precancerous oral mucosa lesion and is closely related to oxidative stress. Cucurbitacin B (CuB), a tetracyclic triterpenoid molecule derived from plants, has shown promising anti-proliferative and antioxidant effects in preclinical studies. However, whether CuB can play an antiproliferative role in OLK by regulating oxidative stress remains elusive.

PURPOSE

To investigate the role of CuB in inhibiting the malignant progression of oral leukoplakia and to further explore its underlying mechanisms of action.

METHODS

In vitro, the effect of CuB on the proliferation, migration, apoptosis, and cell cycle of OLK cells DOK was detected. The core genes and key pathways of OLK and CuB were analyzed in the transcriptome database, by using immunofluorescence, qRT-PCR, and Western blot to evaluate the expression levels of the ferroptosis markers ROS, GSH, MDA, Fe2+, and marker genes SLC7A11, GPX4, and FTH1. Immunohistochemistry of human tissue was performed to investigate the expression of the SLC7A11. In vivo, the model of OLK was established in C57BL/6 mice and the biosafety of CuB treatment for OLK was further evaluated.

RESULTS

CuB substantially suppressed the proliferation of DOK cells. Bioinformatics analysis showed that the core targets of OLK crossing with CuB include SLC7A11 and that the essential pathways involve ROS and ferroptosis. In vitro experiments indicated that CuB might promote ferroptosis by down-regulating the expression of SLC7A11. We observed a gradual increase in SLC7A11 expression levels during the progression from normal oral mucosa to oral leukoplakia with varying degrees of epithelial dysplasia. In vivo experiments demonstrated that CuB inhibited the malignant progression of OLK by promoting ferroptosis in OLK mice and exhibited a certain level of biosafety.

CONCLUSION

This study demonstrated for the first time that CuB could effectively inhibit the malignant progression of OLK by inducing ferroptosis via activating the SLC7A11/ mitochondrial oxidative stress pathway. These findings indicate that CuB could serve as the lead compound for the future development of anti-oral leukoplakia drugs.

Decoding ferroptosis: Revealing the hidden assassin behind cardiovascular diseases

The discovery of regulatory cell death processes has driven innovation in cardiovascular disease (CVD) therapeutic strategies. Over the past decade, ferroptosis, an iron-dependent form of regulated cell death driven by excessive lipid peroxidation, has been shown to drive the development of multiple CVDs. This review provides insights into the evolution of the concept of ferroptosis, the similarities and differences with traditional modes of programmed cell death (e.g., apoptosis, autophagy, and necrosis), as well as the core regulatory mechanisms of ferroptosis (including cystine/glutamate transporter blockade, imbalance of iron metabolism, and lipid peroxidation). In addition, it provides not only a detailed review of the role of ferroptosis and its therapeutic potential in widely studied CVDs such as coronary atherosclerotic heart disease, myocardial infarction, myocardial ischemia/reperfusion injury, heart failure, cardiomyopathy, and aortic aneurysm but also an overview of the phenomenon and therapeutic perspectives of ferroptosis in lesser-addressed CVDs such as cardiac valvulopathy, pulmonary hypertension, and sickle cell disease. This article aims to integrate this knowledge to provide a comprehensive view of ferroptosis in a wide range of CVDs and to drive innovation and progress in therapeutic strategies in this field.

Ginsenoside Rg3 attenuates myocardial ischemia/reperfusion-induced ferroptosis via the keap1/Nrf2/GPX4 signaling pathway

BACKGROUND

Ginsenoside Rg3 is a component of ginseng that protects against myocardial ischemia/reperfusion (MI/R) injury. Ferroptosis is a new form of cell death characterized by oxidative damage to phospholipids. The purpose of this study was to examine the role and of ginsenoside Rg3 in MI/R and the mechanism.

METHODS

A mouse model of left anterior descending (LAD) ligation-induced myocardial ischemia/reperfusion (MI/R) injury and oxygen-glucose deprivation/reperfusion (OGD/R) were used as in vitro and in vivo models, respectively. Echocardiographic analysis, 2,3,5-triphenyltetrazolium chloride (TTC) staining and hematoxylin-eosin (H&E) staining were used to assess the cardioprotective effects of ginsenoside Rg3. Western blotting, biochemical analysis, small interfering RNA analysis and molecular docking were performed to examine the underlying mechanism.

RESULTS

Ginsenoside Rg3 improved cardiac function and infarct size in mice with MI/R injury. Moreover, ginsenoside Rg3 increased the expression of the ferroptosis-related protein GPX4 and inhibited iron deposition in mice with MI/R injury. Ginsenoside Rg3 also activated the Nrf2 signaling pathway. Ginsenoside Rg3 attenuated myocardial ischemia/reperfusion-induced ferroptosis via the Nrf2 signaling pathway. Notably, ginsenoside Rg3 regulated the keap1/Nrf2 signaling pathway to attenuate OGD/R-induced ferroptosis in H9C2 cells. Taken together, ginsenoside Rg3 attenuated myocardial ischemia/reperfusion-induced ferroptosis via the keap1/Nrf2/GPX4 signaling pathway.

CONCLUSIONS

Our findings demonstrated that ginsenoside Rg3 ameliorate MI/R-induced ferroptosis via the keap1/Nrf2/GPX4 signaling pathway.

Ginsenoside Rb2 Inhibits the Pyroptosis in Myocardial Ischemia Progression Through Regulating the SIRT1 Mediated Deacetylation of ASC

Myocardial ischemic (MI) injury is a common cardiovascular disease, and the potential therapeutic effects of ginsenoside Rb2 (Rb2) have been lately the focus of interest. Therefore, this study aimed to investigate the effects of Rb2 on pyroptosis of cardiomyocytes in MI progression. An in vitro MI model was developed by subjecting rat's cardiomyocytes (H9c2) to hypoxia/reoxygenation (H/R). The cell viability was determined by CCK-8 assay, while cell death was analyzed by propidium iodide staining. Similarly, pyroptosis-related protein levels and acetylation levels of apoptosis-associated speck-like protein containing a CARD (ASC) were detected by western blotting, and the relationship between Sirtuin 1 (SIRT1) and ASC was confirmed by co-immunoprecipitation (Co-IP) assay. Moreover, hematoxylin-eosin (H&E) and triphenyl tetrazolium chloride staining were used to study pathological structure and infarct size. It was found that post-Rb2 treatment significantly increased the cell viability and decreased the cell death and lactic dehydrogenase release, while the increased gasdermin D-N, NOD-like receptor thermal protein domain-associated protein 3, ASC, and cleaved-caspase-1 protein levels were significantly decreased in H/R-stimulated H9c2 cells. Moreover, the acetylation levels of H92c cells were decreased post-Rb2 treatment via increasing SIRT1 levels, while knocking down SIRT1, translated into an increase in ASC acetylation levels, leading to the increase in ASC protein stability and expressions. Additionally, the Rb2 effects on pyroptosis in H/R-stimulated H92c cells were reversed by overexpressing ASC, while reduced myocardial tissue damage was observed in MI rats following in vivo Rb2 treatment. Rb2 treatment inhibited pyroptosis in MI progression by decreasing the ASC levels. Mechanistically, Rb2 treatment increased the SIRT1 levels, further increasing the acetylation levels of ASC and decreasing the protein stability of ASC.

Dihydroquercetin improves experimental acute liver failure by targeting ferroptosis and mitochondria-mediated apoptosis through the SIRT1/p53 axis

BACKGROUND

Ferroptosis and mitochondria-mediated apoptosis are both involved in the pathogenesis of acute liver failure (ALF). Ferroptosis-produced reactive oxygen species (ROS) trigger the chain oxidation of polyunsaturated phospholipids and promote mitochondrial apoptosis. Dihydroquercetin (DHQ) also plays an important protective role against liver injury.

PURPOSE

Here, we aimed to investigate the protective effects of DHQ on ALF. We also explored the underlying mechanism.

METHODS

We established a Lipopolysaccharide (LPS)/D-galactosamine (D-Gal)-induced ALF mouse model and tumor necrosis factor-α (TNF-α)/D-Gal-induced ALF LO2 cell model. 2',7'-Dichlorofluorescein diacetate (DCFH-DA) and Dihydroethidium (DHE) were used to detect total ROS levels. Lipid ROS was assessed using C11-BODIPY flow cytometry. Lipid peroxidative products levels were detected using MDA ELISA assay and 4-hydroxynonenal (4-HNE) immunohistochemistry. QRT-PCR and western blots were used to test mRNA and protein expression levels, respectively. Cell viability was evaluated with CCK8 assay, and apoptosis was analyzed using flow cytometry.

RESULTS

DHQ treatment improved LPS/D-Gal-induced ALF, as well as TNF-α/D-Gal-induced reductions in LO2 viability and increased sirtuin 1 (SIRT1) expression. DHQ pretreatment also reduced the accumulation of ROS, reduced lipid peroxidation, elevated mitochondrial membrane potentials (ΔΨm), and decreased liver cell apoptosis both in vivo and in vitro. Additionally, the knockdown of SIRT1 and p53 activator (Tenovin-6) treatment reversed DHQ's inhibitory effects on ferroptosis and mitochondria-mediated apoptosis in vitro. DHQ enhanced p53 deacetylation by both up-regulating SIRT1 expression and directly bonding to SIRT1. We also found that Tenovin-6's stimulatory effects on ferroptosis and mitochondria-mediated apoptosis in the DHQ-treated LO2 ALF cell model were partially attenuated by overexpression of solute carrier family 7member 11 (SLC7A11), as well as by apoptotic protease activating factor 1 (Apaf-1) knockdown.

CONCLUSION

Our results suggest that DHQ alleviated ALF by inhibiting both ferroptosis and mitochondria-mediated apoptosis by regulating the SIRT1/p53 axis. Thus, DHQ may serve as a novel therapy for ALF.

The activation of LBH-CRYAB signaling promotes cardiac protection against I/R injury by inhibiting apoptosis and ferroptosis

Myocardial ischemia-reperfusion (I/R) injury stands out among cardiovascular diseases, and current treatments are considered unsatisfactory. For cardiomyocytes (CMs) in ischemic tissues, the upregulation of Limb-bud and Heart (LBH) and αB-crystallin (CRYAB) and their subsequent downregulation in the context of cardiac fibrosis have been verified in our previous research. Here, we focused on the effects and mechanisms of activated LBH-CRYAB signaling on damaged CMs during I/R injury, and confirmed the occurrence of mitochondrial apoptosis and ferroptosis during I/R injury. The application of inhibitors, ectopic expression vectors, and knockout mouse models uniformly verified the role of LBH in alleviating both apoptosis and ferroptosis of CMs. p53 was identified as a mutual downstream effector for both LBH-CRYAB-modulated apoptosis and ferroptosis inhibition. In mouse models, LBH overexpression was confirmed to exert enhanced cardiac protection against I/R-induced apoptosis and ferroptosis, suggesting that LBH could serve as a promising target for the development of I/R therapy.

Crosstalk among Reactive Oxygen Species, Autophagy and Metabolism in Myocardial Ischemia and Reperfusion Stages

Myocardial ischemia is the most common cardiovascular disease. Reperfusion, an important myocardial ischemia tool, causes unexpected and irreversible damage to cardiomyocytes, resulting in myocardial ischemia/reperfusion (MI/R) injury. Upon stress, especially oxidative stress induced by reactive oxygen species (ROS), autophagy, which degrades the intracellular energy storage to produce metabolites that are recycled into metabolic pathways to buffer metabolic stress, is initiated during myocardial ischemia and MI/R injury. Excellent cardioprotective effects of autophagy regulators against MI and MI/R have been reported. Reversing disordered cardiac metabolism induced by ROS also exhibits cardioprotective action in patients with myocardial ischemia. Herein, we review current knowledge on the crosstalk between ROS, cardiac autophagy, and metabolism in myocardial ischemia and MI/R. Finally, we discuss the possible regulators of autophagy and metabolism that can be exploited to harness the therapeutic potential of cardiac metabolism and autophagy in the diagnosis and treatment of myocardial ischemia and MI/R.

Drug resistance mechanisms and treatment strategies mediated by Ubiquitin-Specific Proteases (USPs) in cancers: new directions and therapeutic options

Drug resistance represents a significant obstacle in cancer treatment, underscoring the need for the discovery of novel therapeutic targets. Ubiquitin-specific proteases (USPs), a subclass of deubiquitinating enzymes, play a pivotal role in protein deubiquitination. As scientific research advances, USPs have been recognized as key regulators of drug resistance across a spectrum of treatment modalities, including chemotherapy, targeted therapy, immunotherapy, and radiotherapy. This comprehensive review examines the complex relationship between USPs and drug resistance mechanisms, focusing on specific treatment strategies and highlighting the influence of USPs on DNA damage repair, apoptosis, characteristics of cancer stem cells, immune evasion, and other crucial biological functions. Additionally, the review highlights the potential clinical significance of USP inhibitors as a means to counter drug resistance in cancer treatment. By inhibiting particular USP, cancer cells can become more susceptible to a variety of anti-cancer drugs. The integration of USP inhibitors with current anti-cancer therapies offers a promising strategy to circumvent drug resistance. Therefore, this review emphasizes the importance of USPs as viable therapeutic targets and offers insight into fruitful directions for future research and drug development. Targeting USPs presents an effective method to combat drug resistance across various cancer types, leading to enhanced treatment strategies and better patient outcomes.

Ferroptosis and Lipid Metabolism in Acute Myocardial Infarction

Acute myocardial infarction (AMI) is triggered by the blockage of coronary arteries, leading to restricted blood flow to the myocardium, which results in damage and cell death. While the traditional understanding of cell death primarily revolves around apoptosis, a new player in the game has emerged: ferroptosis. This novel form of cell death relies on iron and is propelled by reactive oxygen species (ROS). Lipid metabolism, an indispensable physiological process, plays a vital role in preserving cellular homeostasis. However, when this metabolic pathway is disrupted, the accumulation of excess waste increases, specifically lipid peroxides, which are strongly linked to the occurrence and progression of AMI. As a result, comprehending this complex interaction between ferroptosis and lipid metabolism could pave the way for new therapeutic approaches in tackling AMI.

Emerging regulatory mechanisms in cardiovascular disease: Ferroptosis

Ferroptosis, distinct from apoptosis, necrosis, autophagy, and other types of cell death, is a novel iron-dependent regulated cell death characterized by the accumulation of lipid peroxides and redox imbalance with distinct morphological, biochemical, and genetic features. Dysregulation of iron homeostasis, the disruption of antioxidative stress pathways and lipid peroxidation are crucial in ferroptosis. Ferroptosis is involved in the pathogenesis of several cardiovascular diseases, including atherosclerosis, cardiomyopathy, myocardial infarction, ischemia-reperfusion injury, abdominal aortic aneurysm, aortic dissection, and heart failure. Therefore, a comprehensive understanding of the mechanisms that regulate ferroptosis in cardiovascular diseases will enhance the prevention and treatment of these diseases. This review discusses the latest findings on the molecular mechanisms of ferroptosis and its regulation in cardiovascular diseases, the application of ferroptosis modulators in cardiovascular diseases, and the role of traditional Chinese medicines in ferroptosis regulation to provide a comprehensive understanding of the pathogenesis of cardiovascular diseases and identify new prevention and treatment options.

Ferroptosis and the ubiquitin-proteasome system: exploring treatment targets in cancer

Ferroptosis is an emerging mode of programmed cell death fueled by iron buildup and lipid peroxidation. Recent evidence points to the function of ferroptosis in the aetiology and development of cancer and other disorders. Consequently, harnessing iron death for disease treatment has diverted the interest of the researchers in the field of basic and clinical research. The ubiquitin-proteasome system (UPS) represents a primary protein degradation pathway in eukaryotes. It involves labelling proteins to be degraded by ubiquitin (Ub), followed by recognition and degradation by the proteasome. Dysfunction of the UPS can contribute to diverse pathological processes, emphasizing the importance of maintaining organismal homeostasis. The regulation of protein stability is a critical component of the intricate molecular mechanism underlying iron death. Moreover, the intricate involvement of the UPS in regulating iron death-related molecules and signaling pathways, providing valuable insights for targeted treatment strategies. Besides, it highlights the potential of ferroptosis as a promising target for cancer therapy, emphasizing the combination between ferroptosis and the UPS. The molecular mechanisms underlying ferroptosis, including key regulators such as glutathione peroxidase 4 (GPX4), cysteine/glutamate transporter (system XC-), and iron metabolism, are thoroughly examined, alongside the role of the UPS in modulating the abundance and activity of crucial proteins for ferroptotic cell death, such as GPX4, and nuclear factor erythroid 2-related factor 2 (NRF2). As a pivotal regulatory system for macromolecular homeostasis, the UPS substantially impacts ferroptosis by directly or indirectly modulating iron death-related molecules or associated signaling pathways. This review explores the involvement of the UPS in regulating iron death-related molecules and signaling pathways, providing valuable insights for the targeted treatment of diseases associated with ferroptosis.

Irisin attenuates type 1 diabetic cardiomyopathy by anti-ferroptosis via SIRT1-mediated deacetylation of p53

BACKGROUND

Diabetic cardiomyopathy (DCM) is a serious complication in patients with type 1 diabetes mellitus (T1DM), which still lacks adequate therapy. Irisin, a cleavage peptide off fibronectin type III domain-containing 5, has been shown to preserve cardiac function in cardiac ischemia-reperfusion injury. Whether or not irisin plays a cardioprotective role in DCM is not known.

METHODS AND RESULTS

T1DM was induced by multiple low-dose intraperitoneal injections of streptozotocin (STZ). Our current study showed that irisin expression/level was lower in the heart and serum of mice with STZ-induced TIDM. Irisin supplementation by intraperitoneal injection improved the impaired cardiac function in mice with DCM, which was ascribed to the inhibition of ferroptosis, because the increased ferroptosis, associated with increased cardiac malondialdehyde (MDA), decreased reduced glutathione (GSH) and protein expressions of solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4), was ameliorated by irisin. In the presence of erastin, a ferroptosis inducer, the irisin-mediated protective effects were blocked. Mechanistically, irisin treatment increased Sirtuin 1 (SIRT1) and decreased p53 K382 acetylation, which decreased p53 protein expression by increasing its degradation, consequently upregulated SLC7A11 and GPX4 expressions. Thus, irisin-mediated reduction in p53 decreases ferroptosis and protects cardiomyocytes against injury due to high glucose.

CONCLUSION

This study demonstrated that irisin could improve cardiac function by suppressing ferroptosis in T1DM via the SIRT1-p53-SLC7A11/GPX4 pathway. Irisin may be a therapeutic approach in the management of T1DM-induced cardiomyopathy.

Ferroptosis mechanisms and regulations in cardiovascular diseases in the past, present, and future

Cardiovascular diseases (CVDs) are the main diseases that endanger human health, and their risk factors contribute to high morbidity and a high rate of hospitalization. Cell death is the most important pathophysiology in CVDs. As one of the cell death mechanisms, ferroptosis is a new form of regulated cell death (RCD) that broadly participates in CVDs (such as myocardial infarction, heart transplantation, atherosclerosis, heart failure, ischaemia/reperfusion (I/R) injury, atrial fibrillation, cardiomyopathy (radiation-induced cardiomyopathy, diabetes cardiomyopathy, sepsis-induced cardiac injury, doxorubicin-induced cardiac injury, iron overload cardiomyopathy, and hypertrophic cardiomyopathy), and pulmonary arterial hypertension), involving in iron regulation, metabolic mechanism and lipid peroxidation. This article reviews recent research on the mechanism and regulation of ferroptosis and its relationship with the occurrence and treatment of CVDs, aiming to provide new ideas and treatment targets for the clinical diagnosis and treatment of CVDs by clarifying the latest progress in CVDs research.