Ferroptosis as a target for protection against cardiomyopathy

Ophiopogon japonicus polysaccharide reduces doxorubicin-induced myocardial ferroptosis injury by activating Nrf2/GPX4 signaling and alleviating iron accumulation

Doxorubicin (DOX) is a principal chemotherapeutic agent in the domain of oncological intervention. However, its clinical application is constrained due to its severe and irreversible side effects, particularly heart damage. Ferroptosis, characterized by iron accumulation and redox system imbalance, serves a key role in DOX‑induced cardiotoxicity. Ophiopogon japonicus polysaccharide (OJP) exhibits diverse pharmacological activities, including cardiovascular protection, and anti‑inflammatory, anti‑oxidative and immune regulatory effects. However, the role and mechanism of OJP in DOX‑mediated ferroptosis‑triggered injury in cardiomyocytes remain elusive. The present study aimed to assess the effect of OJP on DOX‑induced myocardial ferroptosis injury and to reveal its underlying anti‑ferroptosis mechanism. The detection of myocardial injury markers, such as LDH, indicated that OJP can ameliorate myocardial damage. Additionally, western blot analyses reveal that OJP decreases the expression levels of the ferroptosis‑related marker transferrin receptor 1 (TFR1) while simultaneously increasing expression levels of glutathione peroxidase 4 (GPX4) in a concentration‑dependent manner. Furthermore, fluorescence probe assays demonstrate that OJP not only reduces iron accumulation and oxidative stress but also inhibits the production of lipid peroxidation, as evidenced by a decrease in malondialdehyde (MDA) levels measured. In addition, OJP simultaneously decreased ferroptosis by enhancing mitochondrial function. Mechanistically, OJP attenuated ferroptosis by upregulating the endogenous key antioxidant factor nuclear factor erythroid 2‑related factor 2 (Nrf2), which in turn increased the expression of the downstream signaling molecule GPX4 and reduced the accumulation of the labile iron pool. Therefore, OJP may be a novel therapeutic intervention for DOX‑induced ferroptosis‑triggered myocardial injury.

NSUN2 lactylation drives cancer cell resistance to ferroptosis through enhancing GCLC-dependent glutathione synthesis

Lactate-mediated lactylation on target proteins is recently identified as the novel posttranslational modification with profound biological functions. RNA 5-methylcytosine (m5C) modification possesses dynamic and reversible nature, suggesting that activity of its methyltransferase NSUN2 is actively regulated. However, how NSUN2 activity is response to acidic condition in tumor microenvironment and then regulates cancer cell survival remain to be clarified. Here, we demonstrate that NSUN2 activity is enhanced by lactate-mediated lactylation at lysine 508, which then targets glutamate-cysteine ligase catalytic subunit (GCLC) mRNA to facilitates GCLC m5C formation and mRNA stabilization. The activated GCLC induces higher level of intracellular GSH accompanied by decreased lipid peroxidation and resistant phenotype to ferroptosis induction by doxorubicin (Dox) in gastric cancer cells. Specifically, the effect of NSUN2 lactylation-GCLC-GSH pathway is nearly lost when NSUN2 K508R or GCLC C-A mutant (five cytosine sites) was introduced into the cancer cells. We further identify the catalytic subunit N-α-acetyltransferase 10 (NAA10) as the lactytransferase of NSUN2, and lactate treatment substantially enhances their association and consequent NSUN2 activation. Taken together, our findings convincingly elucidate the signaling axis of NAA10-NSUN2-GCLC that potently antagonizes the ferroptosis under acidic condition, and therefore, targeting NSUN2 lactylation might be an effective strategy in improving the prognosis of cancer patients.

Early detection of anthracycline-induced cardiotoxicity

Although anthracyclines are important anticancer agents, their use is limited due to various adverse effects, particularly cardiac toxicity. Mechanisms underlying anthracycline-induced cardiotoxicity (AIC) are complex. Given the irreplaceable role of anthracyclines in treatment of malignancies and other serious diseases, early monitoring of AIC is paramount. In recent years, multiple studies have investigated various biomarkers for early detection of AIC. Currently, the two most common are cardiac troponin and B-type natriuretic peptide. In addition, a range of other molecules, including RNAs, myeloperoxidase (MPO), C-reactive protein (CRP), various genes, and others, also play roles in AIC prediction. Unfortunately, current research indicates a need to validate their sensitivity and specificity of these biomarkers especially in large study populations. In this review, we summarize the mechanisms and potential biomarkers of AIC, although some remain preliminary.

Shenmai Injection Reduces Cardiomyocyte Apoptosis Induced by Doxorubicin through miR-30a/Bcl-2

OBJECTIVE

To explore the molecular mechanism of Shenmai Injection (SMI) against doxorubicin (DOX) induced cardiomyocyte apoptosis.

METHODS

A total of 40 specific pathogen-free (SPF) male Sprague Dawley (SD) male rats were divided into 5 groups based on the random number table, including the control group, the model group, miR-30a agomir group, SMI low-dose (SMI-L) group, and SMI high-dose (SMI-H) group, with 8 rats in each group. Except for the control group, the rats were injected weekly with DOX (2 mg/kg) in the tail vein for 4 weeks to induce myocardial injury, and were given different regimens of continuous intervention for 2 weeks. Cardiac function was detected by echocardiography and myocardial pathological changes were observed by Van Gieson (VG) staining. Myocardial injury serum markers, including creatine kinase (CK), lactate dehydrogenase (LDH), troponin T (cTnT), N-terminal pro-brain natriuretic peptide (NT-proBNP), soluble ST2 (sST2), and growth differentiation factor-15 (GDF-15) were detected by enzyme linked immunosorbent assay (ELISA). Cardiomyocyte apoptosis was observed by terminal deoxynucleotidyl transferase-mediated biotinylated dUTP triphosphate nick end labeling (TUNEL) and transmission electron microscopy, and the expressions of target proteins and mRNA were detected by Western blot and quantitative real time polymerase chain reaction (qRT-RCR), respectively.

RESULTS

The treatment with different doses of SMI reduced rat heart mass index and left ventricular mass index (P<0.05), significantly improved the left ventricular ejection fraction (P<0.05), decreased the levels of serum CK, LDH, cTnT, and NT-proBNP (P<0.05 or P<0.01), reduced the levels of serum sST2 and GDF-15 (P<0.05 or P<0.01), decreased the collagen volume fraction, reduced the expressions of rat myocardial type I and type III collagen (P<0.05 or P<0.01), and effectively alleviated myocardial fibrosis. And the study found that SMI promoted the expression levels of miR-30a and Bcl-2 in myocardium, and down-regulated the expression of Bax, which inhibited the activation of Caspase-3 and Caspase-9 (P<0.05 or P<0.01), and improved myocardial cell apoptosis.

CONCLUSIONS

SMI can alleviate myocardial injury and apoptosis caused by DOX, and its mechanism possibly by promoting the targeted expression of myocardial Bcl-2 protein through miR-30a.

Doxorubicin or Epirubicin Versus Liposomal Doxorubicin Therapy-Differences in Cardiotoxicity

Doxorubicin (DOX) is an important drug used in the treatment of many malignancies. Unfortunately DOX causes various side effects, with cardiotoxicity being the most characteristic. Risk factors for DOX induced cardiotoxicity (DIC) include cumulative dose of DOX, preexisting cardiovascular diseases, dyslipidemia, diabetes, smoking, along with the use of other cardiotoxic agents. Development of DIC is associated with many pathological phenomena - increased oxidative stress, as well as upregulation of ferroptosis, apoptosis, necrosis, and autophagy. In DIC expression of many microRNAs is also deregulated. In order to avoid cardiotoxicity and still use DOX effectively DOX derivatives such as epirubicin were synthesized. Nowadays a new liposomal form of DOX (L-DOX) appeared as an alternative to conventional treatment with greatly reduced cardiotoxicity. L-DOX can be divided into two groups of substances - pegylated (PLD) with increased solubility and stability, and non-pegylated (NLPD). Many metaanalyses, clinical along with preclinical studies have shown L-DOX treatment is associated with a smaller decrease of left ventricular ejection fraction (LVEF) and other heart functions, but efficacy of this treatment is comparable to the use of convenctional DOX.

miRNA-541-5p regulates myocardial ischemia-reperfusion injury by targeting ferroptosis

BACKGROUND

This article aims to use high-throughput sequencing to identify miRNAs associated with ferroptosis in myocardial ischemia-reperfusion injury, select a target miRNA, and investigate its role in H9C2 cells hypoxia-reoxygenation injury.

METHODS

SD rats and H9C2 cells were used as subjects. ELISA kits quantified MDA, SOD, GSH, LDH, and ferritin levels. TTC staining evaluated infarction size. HE staining observed histopathological changes. DCFH-DA fluorescent probe detected ROS. CCK-8 kit measured cell viability. HiSeq 2000 sequencing performed differential expression analysis of miRNAs. qRT-PCR and Western blots assessed the expression levels of GPX-4, ACSL-4, HO-1, TFR-1 and TFR-2. SPSS 21.0 software conducted statistical analysis.

RESULTS

Myocardial ischemia-reperfusion injury resulted in decreased levels of SOD and GSH, increased levels of LDH and MDA, up-regulation of ferritin, ACSL-4, HO-1, and TFR-2, down-regulation of GPX-4, increased tissue damage, and accumulation of ROS. However, DFO treatment reversed these changes. Subsequently, the target gene miRNA-541-5p was obtained by miRNA sequencing screening, and further validation revealed that miRNA-541-5p expression was increased in the myocardial tissues of rats in the I/R injury model group compared with those of rats in the NC group, P < 0.05. Subsequently, by constructing H9C2 cell lines with miRNA-541-5p overexpression and miRNA-541-5p expression inhibition, miRNA-541-5p expression was inversely correlated with the survival of H9C2 cells after hypoxia-reoxygenation injury. miRNA-541-5p up-regulation led to a decrease in SOD and GSH, an increase in ferritin and MDA, and an accumulation of ROS. wb and qRT-PCT demonstrated that high miRNA-541-5p expression up-regulated the expression of protein/mRNA expression of ACSL-4, HO-1, ferritin, and TFR-1, but down-regulated protein/mRNA expression of GPX-4. In addition, ADAM 7, FNIP 2, HOXD 10, HCCS and STK 3 were preliminarily identified as potential candidate target genes for miRNA-541-5p by bioinformatics analysis. Among them, ADAM7 emerges as the most suitable potential target gene based on the selection criteria.

CONCLUSION

In summary, miRNA-541-5p may be a biomarker of myocardial I/R damage diseases and can regulate oxidative stress and iron death by inhibiting the expression of miRNA-541-5p, thereby reducing mechanisms of I/R injury.

Study on the Synergistic Effect of Klotho and KRAS on Reducing Ferroptosis After Myocardial Infarction by Regulating RAP1/ERK Signaling Pathway

Myocardial infarction (MI) is a coronary artery-related disease that seriously threatens human life and is the leading cause of sudden death worldwide, where a lack of nutrients and oxygen leads to an inflammatory response and death of cardiomyocytes. Ferroptosis is a form of non-apoptotic cell death associated with metabolic dysfunction, resulting in abnormal breakdown of glutamine and iron-dependent accumulation of reactive oxygen species (ROS) during metabolism. However, the molecular mechanism of ferroptosis in the pathogenesis of MI and the function of Klotho and KRAS on ferroptosis during MI remain unclear. The MI rat model was established by LAD ligation with a 6-0 suture. H9c2 cells were placed in glucose-deficient DMEM (Thermo) and cultured in an anaerobic environment (1% CO2 and 5% CO) to establish an in vitro OGD cell model. The damage to rat heart tissue was detected by HE staining, and Klotho and KRAS were determined by RT-qPCR, Western Blot, and IHC. TUNEL staining was used to determine apoptosis in rat heart tissue samples. The interaction between Klotho and KRAS was verified by co-immunoprecipitation and Western Blot. The cardiomyocyte activity was measured by CCK-8 assay. LDH, CK-MB, cTnT, and Fe2+ markers were detected by the kits. For the assessment of ferroptosis, GSH and ROS in cardiomyocytes and serum were detected by kits, and PTSG was detected by Western Blot. IL-1β and IL-6 in cardiomyocytes and serum were determined by ELISA. Klotho was downregulated in MI. Downregulation of Klotho promoted myocardial injury; increased apoptosis of cardiomyocytes; promoted LDH, CK-MB, and cTnT concentrations; inhibited GSH; and promoted ROS levels, PTGS2 expression, and ferroptosis in rats. The same results were obtained in vitro. Klotho and KRAS had endogenous interactions. KRAS knockdown can reverse Klotho knockdown-mediated MI and ferroptosis. RAP1/ERK pathway was highly expressed in MI, and inhibiting RAP1/ERK pathway activation can reverse the promoting effect of overexpressed KRAS on MI progression and ferroptosis. Klotho interacts with KRAS and inhibits ferroptosis after MI by regulating the RAP1/ERK pathway.

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.

Dual-Targeted Drug Delivery to Myeloid Leukemia Cells via Complement- and Transferrin-Based Protein Corona

Although traditionally regarded as an impediment, the protein corona can facilitate the advancement of targeted drug delivery systems. This study presents an innovative approach for targeting acute myeloid leukemia (AML) using nanoparticles with agglutinated protein (NAPs). Agglutinated transferrin and C3b in NAPs selectively bind to CD71 and CD11b, receptors that are overexpressed on myeloid leukemic cells compared to nonmalignant cells. In vitro, NAPs achieved a 73.9% doxorubicin (DOX) uptake in leukemic cells, compared to 6.19% for the free drug, while significantly reducing off-target accumulation in normal cells from 42.9% to 5.76%. In vivo, the distribution of NAPs correlated to the organ infiltration pattern of leukemic cells. NAPs demonstrated antileukemic activity in both in vitro and in vivo NSG mouse models, inducing cell death via apoptosis and ferroptosis. In conclusion, NAP-mediated targeted drug delivery represents a promising therapeutic strategy for AML, enhancing treatment efficacy and minimizing off-target effects.

Mechanisms of postischemic cardiac death and protection following myocardial injury

Acute myocardial infarction (MI) is a leading cause of death worldwide. Although with current treatment, acute mortality from MI is low, the damage and remodeling associated with MI are responsible for subsequent heart failure. Reducing cell death associated with acute MI would decrease the mortality associated with heart failure. Despite considerable study, the precise mechanism by which ischemia and reperfusion (I/R) trigger cell death is still not fully understood. In this Review, we summarize the changes that occur during I/R injury, with emphasis on those that might initiate cell death, such as calcium overload and oxidative stress. We review cell-death pathways and pathway crosstalk and discuss cardioprotective approaches in order to provide insight into mechanisms that could be targeted with therapeutic interventions. Finally, we review cardioprotective clinical trials, with a focus on possible reasons why they were not successful. Cardioprotection has largely focused on inhibiting a single cell-death pathway or one death-trigger mechanism (calcium or ROS). In treatment of other diseases, such as cancer, the benefit of targeting multiple pathways with a "drug cocktail" approach has been demonstrated. Given the crosstalk between cell-death pathways, targeting multiple cardiac death mechanisms should be considered.

N6-methyladenosine modification of SPOP relieves ferroptosis and diabetic cardiomyopathy by enhancing ubiquitination of VDAC3

Understanding the pathogenesis of diabetic cardiomyopathy (DCM), a common microvascular complication affecting the heart, is crucial for identifying new therapeutic targets and intervention strategies for DCM. Our study revealed a significant downregulation in Speckle-type POZ protein (SPOP) expression in DCM, while the overexpression of SPOP improved DCM-induced myocardial dysfunction, injury, fibrosis, hypertrophy, and ferroptosis. Mechanistically, SPOP facilitated the degradation of voltage-dependent anion channel 3 (VDAC3) by enhancing its ubiquitination. M6A demethylase AlkB homolog 5 (ALKBH5) reduced the mRNA stability of SPOP by decreasing m6A modification in its 3'UTR. The m6A reader insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) enhanced the stability of SPOP mRNA through recognition of m6A-modified SPOP 3'UTR. Furthermore, ALKBH5 promoted ferroptosis by inhibiting SPOP-induced VDAC3 degradation, while IGF2BP2 inhibited ferroptosis via activation of SPOP-induced VDAC3 degradation in high glucose-treated neonatal mouse ventricular cardiomyocytes (NMVCs). Overall, our study has unveiled a novel role of SPOP in the pathogenesis of ferroptosis and DCM, thereby significantly advancing our understanding of the involvement of ferroptosis during the progression of DCM. Moreover, this discovery offers promising potential therapeutic interventions targeting DCM.

Erythrophagocytosis-induced ferroptosis contributes to pulmonary microvascular thrombosis and thrombotic vascular remodeling in pulmonary arterial hypertension

BACKGROUND

Whether primary or just as a complication from the progression of pulmonary arterial hypertension (PAH), thrombosis seems to be an important player in this condition. The crosstalk between red blood cells (RBCs) and pulmonary microvascular endothelial cells (PMVECs) and their role in PAH remain undefined.

OBJECTIVES

The goals of this study were to assess the role of RBC-PMVEC interaction in microvascular thrombosis and thrombotic vascular remodeling under hypoxic conditions.

METHODS

We established an in vitro hypoxic coincubation model of RBC and PMVEC as well as a hypoxic mouse model. We investigated erythrophagocytosis (EP), ferroptosis, thrombosis tendency, and pulmonary hemodynamics in experimental PAH.

RESULTS

Increased EP in PMVEC triggered ferroptosis, enhanced procoagulant activity, and exacerbated vessel remodeling under hypoxic conditions. In the PAH mouse model induced by chronic hypoxia, EP-induced ferroptosis followed by upregulated TMEM16F led to a high tendency of thrombus formation and thrombotic vascular remodeling. Inhibition of ferroptosis or silencing of TMEM16F could alleviate hypercoagulable phenotype, reverse right ventricular systolic pressure, right ventricular hypertrophy index, and remodeling of pulmonary vessels.

CONCLUSION

These results illustrate the pathogenic RBC-PMVEC interactions in PAH. Inhibition EP, ferroptosis, or TMEM16F could be a novel therapeutic target to prevent PAH development and thrombotic complications.

An emerging double‑edged sword role of ferroptosis in cardiovascular disease (Review)

The pathophysiology of cardiovascular disease (CVD) is complex and presents a serious threat to human health. Cardiomyocyte loss serves a pivotal role in both the onset and progression of CVD. Among various forms of programmed cell death, ferroptosis, along with apoptosis, autophagy and pyroptosis, is closely linked to the advancement of CVD. Ferroptosis, a mechanism of cell death, is driven by the buildup of oxidized lipids and excess iron. This pathway is modulated by lipid, amino acid and iron metabolism. Key characteristics of ferroptosis include disrupted iron homeostasis, increased peroxidation of polyunsaturated fatty acids due to reactive oxygen species, decreased glutathione levels and inactivation of glutathione peroxidase 4. Treatments targeting ferroptosis could potentially prevent or alleviate CVD by inhibiting the ferroptosis pathway. Ferroptosis is integral to the pathogenesis of several types of CVD and inhibiting its occurrence in cardiomyocytes could be a promising therapeutic strategy for the future treatment of CVD. The present review provided an in‑depth analysis of advancements in understanding the mechanisms underlying ferroptosis. The present manuscript summarized the interplay between ferroptosis and CVDs, highlighting its dual roles in these conditions. Additionally, potential therapeutic targets within the ferroptosis pathway were discussed, alongside the current limitations and future directions of these novel treatment strategies. The present review may offer novel insights into preventive and therapeutic approaches for CVDs.

Doxorubicin and cyclophosphamide mode of chemotherapy-related cardiomyopathy: Review of preclinical model

Over the past 70 years, there has been extensive research focused on preventing chemotherapy-related cardiovascular complications. However, the current state of cardio-oncology research has raised more questions than answers. Experimental studies often present data that are difficult to compare and, at times, contradictory. One notable limitation in translating experimental findings to clinical practice is the reliance on models that administer only one chemotherapeutic drug to experimental animals, despite the common use of multidrug cancer treatments in real clinical settings. This article aims to discuss our own experience in modeling an experimental rat model of cardiomyopathy induced by the administration of two chemotherapeutic drugs, doxorubicin (adriamycin) and cyclophosphamide (AC mode of chemotherapy) - Avagimyan A., et al model, along with a subsequent review of morphological changes based on our personal archive.

A Cardiac-Targeting and Anchoring Bimetallic Cluster Nanozyme Alleviates Chemotherapy-Induced Cardiac Ferroptosis and PANoptosis

Doxorubicin (DOX), a potent antineoplastic agent, is commonly associated with cardiotoxicity, necessitating the development of strategies to reduce its adverse effects on cardiac function. Previous research has demonstrated a strong correlation between DOX-induced cardiotoxicity and the activation of oxidative stress pathways. This work introduces a novel antioxidant therapeutic approach, utilizing libraries of tannic acid and N-acetyl-L-cysteine-protected bimetallic cluster nanozymes. Through extensive screening for antioxidative enzyme-like activity, an optimal bimetallic nanozyme (AuRu) is identified that possess remarkable antioxidant characteristics, mimicking catalase-like enzymes. Theoretical calculations reveal the surface interactions of the prepared nanozymes that simulate the hydrogen peroxide decomposition process, showing that these bimetallic nanozymes readily undergo OH⁻ adsorption and O₂ desorption. To enhance cardiac targeting, the atrial natriuretic peptide is conjugated to the AuRu nanozyme. These cardiac-targeted bimetallic cluster nanozymes, with their anchoring capability, effectively reduce DOX-induced cardiomyocyte ferroptosis and PANoptosis without compromising tumor treatment efficacy. Thus, the therapeutic approach demonstrates significant reductions in chemotherapy-induced cardiac cell death and improvements in cardiac function, accompanied by exceptional in vivo biocompatibility and stability. This study presents a promising avenue for preventing chemotherapy-induced cardiotoxicity, offering potential clinical benefits for cancer patients.

Ferroptosis: Latest evidence and perspectives on plant-derived natural active compounds mitigating doxorubicin-induced cardiotoxicity

Doxorubicin (DOX) is a chemotherapy drug widely used in clinical settings, acting as a first-line treatment for various malignant tumors. However, its use is greatly limited by the cardiotoxicity it induces, including doxorubicin-induced cardiomyopathy (DIC). The mechanisms behind DIC are not fully understood, but its potential biological mechanisms are thought to include oxidative stress, inflammation, energy metabolism disorders, mitochondrial damage, autophagy, apoptosis, and ferroptosis. Recent studies have shown that cardiac injury induced by DOX is closely related to ferroptosis. Due to their high efficacy, availability, and low side effects, natural medicine treatments hold strong clinical potential. Currently, natural medicines have been shown to mitigate DOX-induced ferroptosis and ease DIC through various functions such as antioxidation, iron ion homeostasis correction, lipid metabolism regulation, and mitochondrial function improvement. Therefore, this review summarizes the mechanisms of ferroptosis in DIC and the regulation by natural plant products, with the expectation of providing a reference for future research and development of inhibitors targeting ferroptosis in DIC. This review explores the mechanisms of ferroptosis in doxorubicin-induced cardiomyopathy (DIC) and summarizes how natural plant products can alleviate DIC by inhibiting ferroptosis through reducing oxidative stress, correcting iron ion homeostasis, regulating lipid metabolism, and improving mitochondrial function.

Autosis: a new form of cell death in myocardial ischemia-reperfusion injury

Cardiomyocytes undergo a variety of cell death events during myocardial ischemia‒reperfusion injury (MIRI). Understanding the causes of cardiomyocyte mortality is critical for the prevention and treatment of MIRI. Among the various types of cell death, autosis is a recently identified type of autophagic cell death with distinct morphological and chemical characteristics. Autosis can be attenuated by autophagy inhibitors but not reversed by apoptosis or necrosis inhibitors. In recent years, it has been shown that during the late phase of reperfusion, autosis is activated, which exacerbates myocardial injury. This article describes the characteristics of autosis, autophagic cell death, and the relationship between autophagic cell death and autosis; reviews the mechanism of autosis in MIRI; and discusses its clinical significance.

Asiatic acid ameliorates doxorubicin-induced cardiotoxicity by promoting FPN-mediated iron export and inhibiting ferroptosis

Doxorubicin (DOX), a common chemotherapeutic agent in cancer therapy, is accompanied by pronounced cardiotoxicity. Ferroptosis has been implicated in the pathogenesis and therapeutics of DOX-induced cardiotoxicity (DIC). Asiatic acid (AA), a pentacyclic triterpene from the Chinese medicinal herb Centella asiatica, displays antioxidant, anti-inflammatory, and antiapoptotic activities. In this study, we investigated the beneficial effects of AA against DOX-induced ferroptosis and cardiotoxicity and the underlying mechanisms. A chronic DIC model was established by challenging mice with DOX (5 mg/kg, i.p.) once per week for 4 weeks. Concurrent with DOX insult, the mice were administered AA (25 mg·kg-1·d-1, i.g.). Cardiac function and mechanical properties of isolated cardiomyocytes were evaluated at the end of treatment. We showed that AA administration preserved cardiac function, significantly reduced cardiac injury, and improved cardiomyocyte contractile function in DIC mice. The beneficial effects of AA were causally linked to the inhibition of DOX-induced ferroptosis both in vivo and in vitro. We revealed that AA attenuated DOX-induced iron accumulation in HL-1 cells by increasing FPN-mediated iron export, in a Nrf2-dependent manner. AA upregulated Nrf2 expression and promoted Nrf2 nuclear translocation in DOX-treated HL-1 cells. Moreover, AA-offered benefits against DOX-induced cardiac dysfunction and ferroptosis were abolished by Nrf2 inhibitor ML385 (30 mg·kg-1·d-1, i.p.) administrated 30 min before AA in DIC mice. Our data favor that AA promotes FPN-mediated iron export to inhibit iron overload and ferroptosis in DIC, suggesting its therapeutic potential in the treatment of DIC.

TNFAIP3 affects ferroptosis after traumatic brain injury by affecting the deubiquitination and ubiquitination pathways of the HMOX1 protein and ACSL3

The occurrence and progression of traumatic brain injury involve a complex process. The pathophysiological mechanisms triggered by neuronal damage include various forms of programmed cell death, including ferroptosis. We observed upregulation of TNFAIP3 in mice after traumatic brain injury. Overexpression of TNFAIP3 inhibits HT-22 proliferation and cell viability through ferroptosis. Mechanistically, TNFAIP3 interacts with the HMOX1 protein and promotes its stability through the deubiquitination pathway. Additionally, TNFAIP3 can enhance lipoperoxidation, mitochondrial damage, and neuronal cell death by promoting ACSL3 degradation via NEDD4-mediated ubiquitination. Mice injected with AAV-shTNFAIP3 exhibited reduced neuronal degeneration and improved motor and cognitive function following cortical impact injury. In conclusion, our findings demonstrate that TNFAIP3 deficiency inhibits neuronal cell ferroptosis and ameliorates cognitive impairment caused by traumatic brain injury and demonstrate its potential applicability in the treatment of traumatic brain injury.

Special Issue "New Molecular Insights into Ischemia/Reperfusion"

Ischemia/reperfusion (IR) injury is a complex pathophysiological process in which the restoration of blood flow to ischemic tissue paradoxically exacerbates tissue damage and death [...].

Bufalin Ameliorates Myocardial Ischemia/Reperfusion Injury by Suppressing Macrophage Pyroptosis via P62 Pathway

Bufalin, which is isolated from toad venom, exerts positive effects on hearts under pathological circumstance. We aimed to investigate the effects and mechanisms of bufalin on myocardial I/R injury. In vivo, bufalin ameliorated myocardial I/R injury, which characteristics with better ejection function, decreased infarct size and less apoptosis. The levels of pyroptotic proteins were increased in I/R-treated macrophages and inflammatory cytokines expressed more in I/R-induced mouse, which could be attenuated by bufalin. Bufalin also reduced H/R-treated macrophage pyroptosis in vitro. Autophagic flux blockage and ROS accumulation were reduced by bufalin in impaired macrophages. Overexpression of p62 abrogated the anti-proptosis and anti-oxidative effects of bufalin. The levels of apoptosis related proteins were changed and TUNEL-positive ratio was raised in cardiomyocytes that received conditioned medium treatment with H/R-treated macrophages, while bufalin pretreatment could reduce apoptosis. These findings indicate that bufalin may attenuate myocardial I/R injury by suppressing macrophage pyroptosis via P62 pathway.

Ferroptosis in Cancer: A new perspective on T cells

T cells occupy a pivotal position in the immune response against cancer by recognizing and eliminating cancer cells. However, the tumor microenvironment often suppresses the function of T cells, leading to immune evasion and cancer progression. Recent research has unveiled novel connections among T cells, ferroptosis, and cancer. Ferroptosis is a type of regulated cell death that relies iron and reactive oxygen species and is distinguished by the proliferation of lipid peroxides. Emerging scientific findings underscore the potential of ferroptosis to modulate the function and survival of T cells in the tumor microenvironment. Moreover, T cells or immunotherapy can also affect cancer by modulating ferroptosis in cancer cells. This review delved into the intricate crosstalk between T cells and ferroptosis in the context of cancer, highlighting the molecular mechanisms involved. We also explored the therapeutic potential of targeting ferroptosis to enhance the anticancer immune response mediated by T cells. Understanding the interplay among T cells, ferroptosis, and cancer may provide new insights into developing innovative cancer immunotherapies.

Nrf2 mitigates sepsis-associated encephalopathy-induced hippocampus ferroptosis via modulating mitochondrial dynamic homeostasis

Sepsis-associated encephalopathy (SAE) is a serious neurological complication accompanied with acute and long-term cognitive dysfunction. Ferroptosis is a newly discovered type of cell death that is produced by iron-dependent lipid peroxidation. Emerging evidence suggests that ferroptosis is involved in SAE. The nuclear factor erythroid 2-related factor 2 (Nrf2) is a mitochondria related gene involved in ferroptosis. However, the role of Nrf2 in SAE and the mechanisms remains elusive. In this study, we found that Nrf2 knockout aggravated cognitive and emotional dysfunction and promoted caecal ligation and puncture (CLP)-induced brain injury and hippocampus ferroptosis as indicated by the increase of ROS, Fe2+ and the levels of proinflammatory cytokines. Meanwhile, the levels of glutathione peroxidase 4 (GPX4), SLC7A11 and glutathionewere downregulatedin Nrf2 knockout group. In vitro experiments showed that mitochondrial ROS, Fe2+ and the expression of Fis1 and Drp1 decreased, and the level of Mfn1 and Opa-1 increased after Nrf2 overexpression. The silence of Nrf2 increased the expression of ROS, MDA and Fe2+, while decreased glutathione, mitochondrial membrane potential (MMP) and cell viability in vitro, indicating Nrf2 improved LPS-induced mitochondrial dysfunction and mitigated hippocampal cells ferroptosis. These results suggest that Nrf2 could inhibit ferroptosis and neuroinflammation in hippocampus and reduce cognitive dysfunction in SAE mice, making it a potential therapeutic target in the treatment of SAE. The protective effects of Nrf2 on the brain may be mediated by maintaining mitochondrial dynamic homeostasis.

Stachyose ameliorates myocardial ischemia-reperfusion injury by inhibiting cardiomyocyte ferroptosis and macrophage pyroptosis

Myocardial ischemia-reperfusion injury (MIRI) is a complex pathological process that results from the restoration of blood flow to ischemic myocardium, leading to a series of detrimental effects including oxidative stress and inflammation. Stachyose, a naturally occurring oligosaccharide found in traditional Chinese medicinal herbs, has been suggested to possess therapeutic properties against various pathological conditions. However, its impact on MIRI and the underlying mechanisms have not been fully elucidated. In this study, we aimed to investigate the therapeutic effects of stachyose on MIRI and to uncover the molecular mechanisms involved. Using both in vivo and in vitro models of MIRI, we evaluated the effects of stachyose on cardiac function and cell death pathways. Our results indicate that stachyose significantly improves cardiac function and reduces infarct size in MIRI mice. Mechanistically, stachyose modulates the ferroptotic pathway in cardiomyocytes by upregulating the expression of glutathione peroxidase 4 (GPX4) and reducing lipid peroxides and iron levels. Additionally, stachyose inhibits the pyroptotic pathway in macrophages by downregulating the expression of NLRP3, gasdermin D (GSMD-N), and cleaved-caspase-1, leading to decreased levels of proinflammatory cytokines interleukin (IL)-1β and IL-18. This study demonstrates that stachyose exerts a protective effect against MIRI by targeting both ferroptosis and pyroptosis pathways, suggesting its potential as a novel therapeutic agent for the treatment of MIRI. Further research is warranted to explore the detailed mechanisms and therapeutic potential of stachyose in clinical settings.

Adverse Effects of Nrf2 in Different Organs and the Related Diseases

Significance: Under normal physiological conditions, Nrf2 undergoes ubiquitination and subsequent proteasome degradation to maintain its basal activity. Oxidative stress can trigger Nrf2 activation, prompting its translocation to the nucleus where it functions as a transcription factor, activating various antioxidant pathways, and conferring antioxidant properties. Recent Advances: While extensive research has shown Nrf2's protective role in various diseases, emerging evidence suggests that Nrf2 activation can also produce harmful effects. Critical Issues: This review examines the pathological contexts in which Nrf2 assumes different roles, emphasizing the mechanisms and conditions that result in adverse outcomes. Future Directions: Persistent Nrf2 activation may have deleterious consequences, necessitating further investigation into the specific conditions and mechanisms through which Nrf2 exerts its harmful effects. Antioxid. Redox Signal. 00, 000-000.

MoS2 Nanosheets at Low Doses Induced Cardiotoxicity in Developing Zebrafish via Ferroptosis: Influence of Lateral Size and Surface Modification

The widespread applications of molybdenum disulfide (MoS2) nanosheets inevitably result in their release into aquatic environments, necessitating an exploration of their potential toxic effects on aquatic organisms. This study analyzes the cardiac responses of zebrafish larvae exposed to MoS2, with a focus on the influence of size and surface modifications. At higher concentrations (1 and 5 mg/L), MoS2 nanosheets hampered larval growth without influencing cardiomyogenesis. At lower doses (0.5-100 μg/L), small-sized MoS2 (ssMoS2, 187.2 nm) significantly impaired cardiac development, as proved by morphology abnormality, decreased heartbeat, stroke volume, and cardiac output, whereas these undesirable changes were not observed in the cysteine-modified form. Large-sized nanosheets (1.638 μm) did not localize to the heart, barely showing a cardiac disorder. Transcriptomics, biochemical analysis, and computational simulation validated that ssMoS2 aggravated Fe2+ overload through excessive ferritinophagy and ferroportin-1 inhibition, accompanied by down-regulation of glutathione peroxidase 4 and activation of PUFAs esterification, leading to ferroptosis. Significant associations between ferroptosis signals and cardiac indices, along with the ferrostatin-1 inhibition test, confirmed the ferroptosis-mediated cardiotoxicity of ssMoS2. Our study provides a key understanding of molecular events underlying MoS2-induced cardiotoxicity and highlights the importance of size and surface characteristics, which are significant for risk assessment and the safe design of nanoproducts.

Unveiling Key Biomarkers and Mechanisms in Septic Cardiomyopathy: A Comprehensive Transcriptome Analysis

Purpose

Septic cardiomyopathy (SCM) is a significant global public health concern characterized by substantial morbidity and mortality, which has not been improved for decades due to lack of early diagnosis and effective therapies. This study aimed to identify hub biomarkers in SCM and explore their potential mechanisms.

Methods

We utilized the GSE53007 and GSE207363 datasets for transcriptome analysis of normal and SCM mice. Hub biomarkers were identified through a protein-protein interaction (PPI) network and validated using LPS-treated C57/BL6 mice. Functional enrichment analysis was performed to uncover relevant signaling pathways, while single-cell RNA sequencing was used to examine key genes and regulatory mechanisms associated with SCM.

Results

A total of 374 differentially expressed genes (DEGs) were identified, with 268 genes up-regulated and 106 genes down-regulated. Functional enrichment highlighted chemokine activity and receptor binding, with KEGG pathways revealing significant involvement of the TNF and IL-7 signaling pathways. Deterioration of cardiac function, elevated inflammatory markers such as IL-1β, IL-6, and increased cardiac injury biomarkers such as cTnI indicated the successful establishment of our SCM model. Subsequently, qPCR was conducted to validate the expression of the top 10 genes, through which we identified Cd40, Tlr2, Cxcl10, Ccl5, Cxcl1, Cd14, Gbp2, Ifit2, and Vegfa as key biomarkers. Single-cell sequencing indicated increased neutrophil and macrophage populations, with decreased B cells and cardiomyocytes. Additionally, transcription regulators Irf1 and Stat1 were found to potentially regulate the expression of Gbp2, Cxcl10, Ccl5, and Cd40, linking SCM to immune response, ferroptosis, pyroptosis, cuproptosis, and m6A RNA methylation modification.

Conclusion

This study identified nine hub biomarkers and two transcription regulators associated with SCM. Exploring the connections between SCM and immunity, ferroptosis, pyroptosis, cuproptosis, and m6A RNA methylation might provide insights into the underlying mechanisms. These findings enhanced our understanding of SCM's underlying mechanisms and might pave the way for novel therapeutic strategies to improve clinical outcomes.

Ferroptosis, a therapeutic target for cardiovascular diseases, neurodegenerative diseases and cancer

The identification of ferroptosis represents a pivotal advancement in the field of cell death research, revealing an entirely novel mechanism of cellular demise and offering new insights into the initiation, progression, and therapeutic management of various diseases. Ferroptosis is predominantly induced by intracellular iron accumulation, lipid peroxidation, or impairments in the antioxidant defense system, culminating in membrane rupture and consequent cell death. Studies have associated ferroptosis with a wide range of diseases, and by enhancing our comprehension of its underlying mechanisms, we can formulate innovative therapeutic strategies, thereby providing renewed hope for patients.

Baicalin improves isoproterenol-induced cardiac remodeling by regulating the Nrf2-dependent signaling pathway

BACKGROUND

Cardiovascular disease carries the highest mortality rate among diseases, and pharmacological interventions have limited efficacy. Baicalin (Bai) promotes biological metabolic processes, eliminates oxygen free radicals, and is anti-inflammatory. This study aimed to investigate the effect of Bai on the cardiac injury model induced by isoproterenol in mice.

METHODS AND RESULT

In this study, all groups except the control received intraperitoneal injections of isoproterenol (ISO) to induce a cardiac injury model, with the drug administered continuously for 14 days. hematoxylin and eosin staining and Masson's trichrome staining revealed that Bai significantly mitigated ISO-induced pathological changes in mouse heart tissue and alleviated myocardial hypertrophy. Echocardiography assessments demonstrated that Bai preserved cardiac function in ISO-treated mice. Furthermore, our findings indicated that Bai activated the Nrf2 signaling pathway in vivo and in vitro. To delve deeper, mice were further treated with ML385 (ML) via intraperitoneal injection to inhibit the Nrf2 pathway. Results showed that ML385 blocked the cardioprotective effects of Bai in mouse heart tissue.

CONCLUSION

Bai protects against ISO-induced cardiac injury, and its mechanism is related to activating the Nrf2/HO-1 signaling pathway to regulate cardiac ferroptosis and improve cardiac remodeling.

Immunomodulatory Effects of SPHK1 and Its Interaction with TFAP2A in Yellow Drum (Nibea albiflora)

Sphingosine kinases (SPHKs) are essential enzymes that catalyze the phosphorylation of sphingosine to produce sphingosine-1-phosphate (S1P), which plays pivotal roles in inflammation and immune regulation. In this study, genome-wide association analysis (GWAS) identified the Ydsphk1 gene as closely associated with the resistance of yellow drum (Nibea albiflora) to Vibrio harveyi. Structural prediction showed that YDSPHK1 contains a typical diacylglycerol kinase catalytic (DAGKc) domain (154-291 aa). By constructing and transfecting Ydsphk1 expression plasmids into yellow drum kidney cells, we found that YDSPHK1 is localized in the cytoplasm. Subsequent RNA-Seq analysis of an overexpression plasmid identified 25 differentially expressed genes (DEGs), including 13 upregulated and 12 downregulated. Notably, nsun5 and hsp90aa1 were significantly upregulated, while Nfkbia and hmox1 were downregulated. Promoter analysis indicated that the core regulatory regions of Ydsphk1 are located between -1931~-1679 bp and -419~+92 bp, with two predicted TFAP2A binding sites in the -419~+92 bp region. Further studies demonstrated that varying concentrations of TFAP2A significantly reduced Ydsphk1 promoter activity. These findings underscore the pivotal role of Ydsphk1 in regulating immune responses in yellow drum, particularly through its impact on key immune-related genes and pathways such as NF-κB signaling and ferroptosis. The identification of Ydsphk1 as a mediator of immune regulation provides valuable insights into the molecular mechanisms of immune defense and highlights its potential as a target for enhancing pathogen resistance in aquaculture practices. This study lays a strong foundation for future research aimed at developing innovative strategies for disease management in aquaculture species.

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.

The Daunomycin: Biosynthesis, Actions, and the Search for New Solutions to Enhance Production

Daunorubicin (DNR) is an anthracycline antibiotic originating from soil-dwelling actinobacteria extensively used to treat malignant tumors. Over the decades, extensive attempts were made to enhance the production of anthracyclines by introducing genetic modifications and mutations in combination with media optimization, but the target production levels remain comparatively low. Developing an appropriate culture medium to maximize the yield of DNR and preventing autotoxicity for the producing organism remains a challenge. Our prospective review sheds light on a method involving perturbation that enhances the precursors to regulate the type II PKS pathway, enhancing cells' capacity to increase secondary metabolite production. The suggested method also entails the preparation of culture media for the cultivation of Streptomyces sp. and enhanced yield of DNR, as well as making it inactive with iron or its reduced forms following efflux from the producer. The iron or iron-DNR complex is encapsulated by oleic acid or lipid micelle layers in the culture media, finally resulting in the generated inactive DNR and the DNR-iron-oil complex. This idea has the potential to protect the producer organism from autotoxicity and prevent the inhibition of metabolite production. The approach of substituting sugar with oil in culture media has a dual role wherein it promotes Streptomyces growth by utilizing lipids as an energy source and encapsulating the generated DNR-iron complex in the medium. In this review, we discussed aspects like anthracycline producers, biosynthesis pathways, and gene regulation; side effects of DNR; mechanisms for autotoxicity evasion; and culture media components for the enhancement of DNR production in Streptomyces sp. We anticipate that our work will help researchers working with secondary metabolites production and decipher a methodology that would enhance DNR yield and facilitate the extraction of the resulting DNR by lowering costs in large-scale fermentation.

Ferroptosis and its role in osteoarthritis: mechanisms, biomarkers, and therapeutic perspectives

Osteoarthritis (OA) is one of the leading causes of disability worldwide, characterized by a complex pathological process involving cartilage degradation, synovial inflammation, and subchondral bone remodeling. In recent years, ferroptosis, a form of programmed cell death driven by iron-dependent lipid peroxidation, has been recognized as playing a critical role in the onset and progression of OA. Investigating the molecular mechanisms of ferroptosis and its involvement in OA may offer novel strategies for diagnosing and treating this disease. This review first outlines the core mechanisms of ferroptosis, with a particular focus on the roles of critical molecules such as Glutathione Peroxidase 4 (GPX4), Transferrin Receptor 1 (TfR1), and Nuclear Receptor Coactivator 4 (NCOA4). Subsequently, this study examines the specific impacts of ferroptosis on the pathophysiology of OA. Building on this, the potential of ferroptosis-related biomarkers for OA diagnosis and treatment is highlighted, along with proposed therapeutic strategies targeting ferroptosis regulation. This review aims to deepen the understanding of ferroptosis mechanisms and advance the clinical application of regulatory therapies for OA.

Dual functions of silibinin in attenuating aortic dissection via regulating iron homeostasis and endoplasmic reticulum stress against ferroptosis

Aortic dissection (AD) poses a significant threat to cardiovascular health globally, yet its underlying mechanisms remain elusive. Smooth muscle cells death and phenotypic switching are critically important pathological processes in AD. Currently, no pharmacological therapies have proven effective in managing AD. This study aims to elucidate the involvement of ferroptosis in AD progression and explore ferroptosis inhibition as a potential therapeutic approach for AD management. Elevated expression of ferroptosis markers (HMOX1, ACSL4, and 4-HNE) was observed in AD patients and β-Aminopropionitrile (BAPN)-induced mice. In vivo administration of silibinin (SIL) attenuated aortic dilation, inflammation, mitochondrial injury, and ferroptosis. SIL treatment enhanced cell viability and mitochondrial function while reducing reactive oxygen species (ROS) generation and mitigating ferroptosis in primary human aortic smooth muscle cells (HASMCs) induced by RSL3 or IKE. Mechanistically, RNA-sequencing analysis identified dysregulation of iron homeostasis and endoplasmic reticulum stress, which were modulated by SIL. Molecular docking, cellular thermal shift assay, drug affinity responsive target stability, and surface plasmon resonance analysis confirmed HMOX1 as a direct target of SIL, highlighting its role in modulating iron homeostasis. Moreover, NCT-502, a PHGDH inhibitor, reversed the protective effect of SIL in RSL3-induced HASMCs. Conversely, 4-PBA and ZnPP demonstrate a facilitative role. This suggests that SIL plays a crucial role in ferroptosis development by modulating iron homeostasis and endoplasmic reticulum stress-mediated serine biosynthesis, both in vitro and in vivo. Iron homeostasis and endoplasmic reticulum stress of HASMCs drive the development of aortic dissection. These findings unveil a novel role of SIL in mitigating ferroptosis in HASMCs, offering a promising therapeutic avenue for treating AD.

Evolution of Theories on Doxorubicin-Induced Late Cardiotoxicity-Role of Topoisomerase

Doxorubicin (DOX) has been widely used as a cytotoxic chemotherapeutic. However, DOX has a number of side effects, such as myelotoxicity or gonadotoxicity, the most dangerous of which is cardiotoxicity. Cardiotoxicity can manifest as cardiac arrhythmias, myocarditis, and pericarditis; life-threatening late cardiotoxicity can result in heart failure months or years after the completion of chemotherapy. The development of late cardiomyopathy is not yet fully understood. The most important question is how DOX reprograms the cardiomyocyte, after which DOX is excreted from the body, initially without symptoms. However, clinically overt cardiomyopathy develops over the following months and years. Since the 1980s, DOX-induced disorders in cardiomyocytes have been thought to be related to oxidative stress and dependent on the Fe/reactive oxygen species (ROS) mechanism. That line of evidence was supported by dexrazoxane (DEX) protection, the only Food and Drug Administration (FDA)-approved drug for preventing DOX-induced cardiomyopathy, which complexes iron. Thus, the hypothesis related to Fe/ROS provides a plausible explanation for the induction of the development of late cardiomyopathy via DOX. However, in subsequent studies, DEX was used to identify another important mechanism in DOX-induced cardiomyopathy that is related to topoisomerase 2β (Top2β). Does the Top2β hypothesis explain the mechanisms of the development of DOX-dependent late heart failure? Several of these mechanisms have been identified to date, proving the involvement of Top2β in the regulation of the redox balance, including oxidative stress. Thus, the development of late cardiomyopathy can be explained based on mechanisms related to Top2β. In this review, we highlight free radical theory, iron imbalance, calcium overload, and finally, a theory based on Top2β.

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.

Ferrostatin-1 improves acute sepsis-induced cardiomyopathy via inhibiting neutrophil infiltration through impaired chemokine axis

Introduction

Sepsis-induced cardiomyopathy is a common complication of sepsis and is associated with higher mortality. To date, effective diagnostic and management strategies are still lacking. Recent studies suggest that ferroptosis plays a critical role in sepsis-induced cardiomyopathy and ferroptosis inhibitor Ferrostatin-1 (Fer-1) improved cardiac dysfunction and survival in lipopolysaccharide (LPS) induced endotoxemia. However, the effects of Fer-1 in cardiac dysfunction in the early stages of cecal ligation and puncture (CLP) induced sepsis remains unclear. Our study aims to elucidate the role of Fer-1 in the acute phase of peritonitis sepsis induced cardiac injury.

Methods and Results

CLP was used to induce peritonitis sepsis in mice. Pretreatment of ferroptosis inhibitor ferrostatin-1 (Fer-1) was used in the in vivo models. Survival was monitored for 48h. Cardiac function and histology were analyzed 6h after surgery. We found that ejection fraction (EF) remained normal at 6h after CLP, but the contractility detected by cardiac muscle strain analysis was significantly reduced, along with increased immune cell infiltration. Pretreating the CLP mice with 5 mg/kg Fer-1 significantly reduced mortality. At 6h after CLP, ferroptosis key regulator Gpx4, cardiac iron and malonaldehyde (MDA) did not change, but ferroptosis marker gene expression increased. Fer-1 treatment showed beneficial effects in cardiac function, less myocardial inflammatory cytokine expression and significantly inhibited immune cells, especially neutrophil infiltration in the heart. Consistently, expression of neutrophil associated chemokines (Ccrl2, Cxcl2, Cxcl3 and Cxcl5) as well as extracellular matrix (ECM) degradation enzymes (Adamts1, Adamts4, Adamts9 and Mmp8) significantly decreased in Fer-1 pre-treated CLP heart.

Conclusion and Discussion

Our findings suggest that Fer-1 inhibits neutrophil infiltration in early sepsis by disrupting the chemokine axis, highlighting its potential as a therapeutic option to manage acute immune overactivation in early stages of sepsis-induced cardiomyopathy.

A Redox-Triggered Polymeric Nanoparticle for Disrupting Redox Homeostasis and Enhanced Ferroptosis

Cancer cells possess an efficient redox system, enabling them to withstand oxidative damage induced by treatments, especially in hypoxia areas and ferroptosis can disrupt redox homeostasis in cancer cell. Herein, GSH-sensitive nanoparticles are constructed that induce ferroptosis by long-lasting GSH depletion and enhanced PDT. Carbonic anhydrase IX inhibitor, protoporphyrin IX (Por) complexed with Fe and epirubicin (EPI) are grafted to hyaluronic acid (HA) via disulfide bonds to obtain HSPFE and loaded xCT inhibitor SAS for fabricating SAS@HSPFE which is actively targeted to deep hypoxic tumor cells, and explosively releasing EPI, Por-Fe complex and SAS due to at high GSH concentration. Specifically, SAS inhibited the GSH biosynthesis, and the generation of ROS by Por and the involvement of Fe2+ in the Fenton reaction jointly facilitates oxidative stress. Besides, Fe2+ reacted with excess H2O2 to produce O2, which continuously fuels PDT. GPX4 and SLC7A11 related to antioxidant defense are down-regulated, while ACSL4 and TFRC promoting lipid peroxidation and ROS accumulation are up-regulated, which enhanced ferroptosis by amplifying oxidative stress and suppressing antioxidant defense. SAS@HSPFE NPs revealed highly efficient antitumor effect in vivo study. This study provides a novel approach to cancer treatment by targeting redox imbalance.

Thiolutin Alleviates Cardiotoxic Effects of Doxorubicin by Suppressing NLRP3 Inflammasome in the Mouse Model

Doxorubicin (DOX) has a limitation in clinical oncology due to its dose-dependent cardiotoxicity. Thiolutin (THL) can undermine DOX-induced cardiomyocyte injury by inhibiting the NLRP3 inflammasome activation, yet the efficacy of THL in DOX-induced cardiotoxicity (DOXIC) needs to be validated in animal models. DOX-induced mice were treated with THL to evaluate the efficacy of THL. Relative NLRP3 mRNA levels were determined by quantitative PCR. Blood samples were collected from diffuse large B-cell lymphoma (DLBCL) patients with or without DOXIC to validate serum levels of cTnT, IL-1β, CRP, BNP, and IL-18 by enzyme-linked immunosorbent assay. Apoptosis and pyroptosis-related protein levels were analyzed by western blot. Cardiac function and histopathological changes were determined by echocardiography, HE, Masson's, and wheat germ agglutinin staining. In clinical samples, NLRP3 mRNA and/or protein levels were also markedly heightened in peripheral blood mononuclear cells and serum samples from DOXIC patients, along with higher concentrations of IL-18, cTnT, and IL-1β. Importantly, cTnT possessed a positive correlation with NLRP3 mRNA, IL-1β, and IL-18. Moreover, cTnT possessed a positive correlation with NLRP3 mRNA, IL-1β, and IL-18 levels, suggesting a potential link between DOXIC and NLRP3 inflammasome. The outcomes demonstrated that THL reduced LVEF and LVFS, as well as elevated LVESD and LVEDD in DOX-challenged mice, accompanied by elevated serum concentrations of cTnT, CRP, and BNP. In addition, THL attenuated DOX-induced myocardial hypertrophy and cardiac fibrosis in mice, in conjunction with attenuation of DOX-induced upregulation of C-caspase3, Bax, NLRP3, C-caspase-1/Pro-caspase, GSDMD-N/GSDMD, IL-1β, and IL-18 in heart or serum samples. In conclusion, our data supported that THL alleviates the cardiotoxic effects of DOX and suppresses NLRP3 inflammasome in the mouse model, suggesting that THL as a potential drug for DOXIC.

Lipocalin-2 silencing alleviates sepsis-induced liver injury through inhibition of ferroptosis

INTRODUCTION AND OBJECTIVES

Liver plays a key role in sepsis, a systemic inflammatory response syndrome caused by infection. Ferroptosis is involved in sepsis-induced liver injury. We aimed to assess the changes in ferroptosis in cecal ligation and puncture (CLP)-induced septic mice, and determine the role of lipocalin-2 (LCN2) in liver ferroptosis.

MATERIALS AND METHODS

CLP was used to induce sepsis in mice. The morphological changes in liver tissues and mitochondrial structure were observed using hematoxylin and eosin staining and transmission electron microscopy. The levels of serum alanine transaminase, aspartate aminotransferase, superoxide dismutase, and malondialdehyde were detected using the corresponding kits. The changes of reactive oxygen species level in liver tissues were detected using dihydroethidium as a fluorescence probe. LCN2, cysteine-glutamate reverse transport system, and dihydroorotate dehydrogenase protein levels in the liver were detected by western blotting. The ferroptosis inhibitor ferrostatin-1 (Fer-1), iron chelator dexrazoxane (DXZ), iron-dextran, and LCN2 knockdown studies were performed to determine role of ferroptosis and LCN2 in liver injury during sepsis.

RESULTS

Ferroptosis levels increased in the liver tissues of CLP-induced septic mice. Both Fer-1 and DXZ suppressed ferroptosis and attenuated liver injury following sepsis challenge, whereas iron-dextran increased ferroptosis and liver injury in mice with sepsis. LCN2 knockdown suppressed ferroptosis and reduced oxidative stress in the liver.

CONCLUSIONS

Ferroptosis inhibition attenuates septic liver injury. LCN2 knockdown alleviates sepsis-induced liver injury by inhibiting ferroptosis and reducing oxidative stress.

Down-regulation of HSPB1 and MGST1 promote ferroptosis and impact immune infiltration in diabetic cardiomyopathy

Diabetic cardiomyopathy (DCM) is a leading cause of death in diabetic patients. Current therapies do not adequately resolve this problem and focus only on the optimal level of blood glucose for patients. Ferroptosis plays an important role in diabetes mellitus and cardiovascular diseases. However, the role of ferroptosis in DCM remains unclear. Differentially expressed ferroptosis-related genes (DE-FRGs) were identified by intersecting GSE26887 dataset and the Ferroptosis Database (FerrDb). The associations between the DE-FRGs and immune cells in DCM, estimated by CIBERSORTx algorithm, were analyzed. Using ow cytometry (FCM) to evaluated the infiltration of immune cells of myocardial tissues. The expression of DE-FRGs, Glutathione peroxidase 4 (GPX4) and Solute carrier family 7 member 11 (SLC7A11) were examined by real-time quantitative PCR and western blotting. 3 DE-FRGs were identified, which are Heat shock protein family B (small) member 1 (HSPB1), Microsomal glutathione S-transferase 1 (MGST1) and solute carrier family 40 member 1 (SLC40A1) respectively, and they were closely linked to immune cells in DCM. In vivo, the levels of CD8 + T cells, B cells and Treg cells were significantly decreased in the DCM group, while the levels of CD4 + T cells, M1 cells, M2 cells and monocytes were increased. Diabetes significantly decreased HSPB1 and MGST1 levels and increased ferroptosis compared to normal group. Furthermore, ferroptosis inhibitor ferrostatin-1 (Fer-1) alleviated high-fat diet (HFD)-induced cadiomyocyte injury and rescued the ferroptosis. This study suggests that ferroptosis related gene HSPB1 and MGST1 are closely related to immune cell infiltration, which may become therapeutic targets for DCM.

Ferroptosis in Cardiovascular Diseases and Ferroptosis-Related Intervention Approaches

OBJECTIVE

Cardiovascular diseases (CVDs) are major public health problems that threaten the lives and health of individuals. The article has reviewed recent progresses about ferroptosis and ferroptosis-related intervention approaches for the treatment of CVDs and provided more references and strategies for targeting ferroptosis to prevent and treat CVDs.

METHODS

A comprehensive review was conducted using the literature researches.

RESULTS AND DISCUSSION

Many ferroptosis-targeted compounds and ferroptosis-related genes may be prospective targets for treating CVDs and our review provides a solid foundation for further studies about the detailed pathological mechanisms of CVDs.

CONCLUSION

There are challenges and limitations about the translation of ferroptosis-targeted potential therapies from experimental research to clinical practice. It warrants further exploration to pursure safer and more effective ferroptosis-targeted thereapeutic approaches for CVDs.

Decoding ferroptosis: transforming orthopedic disease management

As a mechanism of cell death, ferroptosis has gained popularity since 2012. The process is distinguished by iron toxicity and phospholipid accumulation, in contrast to autophagy, apoptosis, and other cell death mechanisms. It is implicated in the advancement of multiple diseases across the body. Researchers currently know that osteosarcoma, osteoporosis, and other orthopedic disorders are caused by NRF2, GPX4, and other ferroptosis star proteins. The effective relief of osteoarthritis symptoms from deterioration has been confirmed by clinical treatment with multiple ferroptosis inhibitors. At the same time, it should be reminded that the mechanisms involved in ferroptosis that regulate orthopedic diseases are not currently understood. In this manuscript, we present the discovery process of ferroptosis, the mechanisms involved in ferroptosis, and the role of ferroptosis in a variety of orthopedic diseases. We expect that this manuscript can provide a new perspective on clinical diagnosis and treatment of related diseases.

Protective effect of thymoquinone against doxorubicin-induced cardiotoxicity and the underlying mechanism

BACKGROUND

Ferroptosis is a key process in doxorubicin (DOX)-induced cardiotoxicity and is a potentially important therapeutic target. Thymoquinone (TQ) is a monoterpenoid compound isolated from black cumin extract that exhibits antitumor effects and acts as a powerful mitochondrial-targeted antioxidant. In this study, we investigated the effect of TQ on DOX-induced cardiotoxicity and the potential underlying mechanisms.

METHODS AND RESULTS

Mice were randomly assigned to the control (CON) group, DOX (20 mg/kg) group, TQ10 (10 mg/kg/d) group, and TQ20 (20 mg/kg/d) group and intraperitoneally injected with DOX and different doses of TQ. The electrocardiogram, blood pressure, and cardiac ultrasound changes during the experiments showed that TQ exerted a protective effect against DOX-induced cardiotoxicity. The glutathione (GSH), malondialdehyde (MDA), and total antioxidant capacity (T-AOC) levels in the mouse heart tissue were significantly different from those in the CON group. Western blot analysis revealed that the expression of nuclear factor E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), glutathione peroxidase 4 (GPX4), and ferritin heavy chain 1 (FTH1) in the DOX group was lower than that in the control group. TQ treatment decreased these changes, indicating that TQ alleviated DOX-induced cardiotoxicity and increased the antioxidant capacity of murine cardiomyocytes. The mechanism might involve activating the Nrf2/HO-1 signaling pathway and reducing iron-mediated death. Immunohistochemical staining revealed similar effects on the expression levels of NQO1, COX-2, and NOX4. Moreover, transmission electron microscopy indicated that TQ protected murine cardiomyocytes against DOX-induced mitochondrial damage.

CONCLUSION

The results of this study suggested that TQ can decrease oxidative stress levels and DOX-induced cardiotoxicity by activating the Nrf2/HO-1 signaling pathway to alleviate ferroptosis in murine cardiomyocytes.

CRISPRi/a screens in human iPSC-cardiomyocytes identify glycolytic activation as a druggable target for doxorubicin-induced cardiotoxicity

Doxorubicin is limited in its therapeutic utility due to its life-threatening cardiovascular side effects. Here, we present an integrated drug discovery pipeline combining human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (iCMs), CRISPR interference and activation (CRISPRi/a) bidirectional pooled screens, and a small-molecule screening to identify therapeutic targets mitigating doxorubicin-induced cardiotoxicity (DIC) without compromising its oncological effects. The screens revealed several previously unreported candidate genes contributing to DIC, including carbonic anhydrase 12 (CA12). Genetic inhibition of CA12 protected iCMs against DIC by improving cell survival, sarcomere structural integrity, contractile function, and calcium handling. Indisulam, a CA12 antagonist, can effectively attenuate DIC in iCMs, engineered heart tissue, and animal models. Mechanistically, doxorubicin-induced CA12 potentiated a glycolytic activation in cardiomyocytes, contributing to DIC by interfering with cellular metabolism and functions. Collectively, our study provides a roadmap for future drug discovery efforts, potentially leading to more targeted therapies with minimal off-target toxicity.

PACS2/CPT1A/DHODH signaling promotes cardiomyocyte ferroptosis in diabetic cardiomyopathy

OBJECTIVES

The pathophysiology of diabetic cardiomyopathy (DCM) is a phenomenon of great interest, but its clinical problems have not yet been effectively addressed. Recently, the mechanism of ferroptosis in the pathophysiology of various diseases, including DCM, has attracted widespread attention. Here, we explored the role of PACS2 in ferroptosis in DCM through its downregulation of PACS2 expression.

METHODS AND RESULTS

Cardiomyocytes were treated with high glucose and palmitic acid (HGPA), and the detection of cardiomyocyte iron ions, lipid peroxides, and reactive oxygen species (ROS) revealed clear ferroptosis during these treatments. Silencing PACS2 downregulated CPT1A expression and upregulated DHODH expression significantly, reversing HGPA-induced ferroptosis. Further silencing of PACS2 with a CPT1A agonist exacerbated cardiomyocyte ferroptosis while promoting mitochondrial damage in cardiomyocytes. Using a mouse model of type 2 diabetes induced by streptozotocin (STZ) and a high-fat diet (HFD), we found that PACS2 deletion reversed these treatment-induced increases in cellular iron ions, impaired cardiac function, mitochondrial damage and ferroptosis in cardiac muscle tissues.

CONCLUSIONS

The PACS2/CPT1A/DHODH signalling pathway may be involved in ferroptosis in DCM by regulating cardiomyocyte mitochondrial function.

Intracellular biliverdin dynamics during ferroptosis

Ferroptosis is a cell death mechanism mediated by iron-dependent lipid peroxidation. Although ferroptosis has garnered attention as a cancer-suppressing mechanism, there are still limited markers available for identifying ferroptotic cells or assessing their sensitivity to ferroptosis. The study focused on biliverdin, an endogenous reducing substance in cells, and examined the dynamics of intracellular biliverdin during ferroptosis using a biliverdin-binding cyanobacteriochrome. It was found that intracellular biliverdin decreases during ferroptosis and that this decrease is specific to ferroptosis amongst different forms of cell death. Furthermore, the feasibility of predicting sensitivity to ferroptosis by measuring intracellular biliverdin was demonstrated using a ferroptosis model induced by the re-expression of the transcription factor BACH1. These findings provide further insight into ferroptosis research and are expected to contribute to the development of cancer therapies that exploit ferroptosis.

State-of-the-Art Nrf2 Inhibitors: Therapeutic Opportunities in Non-Cancer Diseases

Nuclear factor erythroid 2-related factor (Nrf2) is a cytoprotective transcription factor that induces the transcription of genes responsible for the cell's response to oxidative stress. While Nrf2 activation has led to the development of clinically relevant therapeutics, the oncogenic role of Nrf2 in the proliferation of cancer cells has underscored the complex nature of Nrf2 and the necessity for the development of Nrf2 inhibitors. Although the application of Nrf2 inhibitors appears limited as anticancer agents, recent studies have begun to pinpoint the impairment of autophagy in diseases as a cellular marker that shifts Nrf2 from a protective to a deleterious state. Therefore, the cytoplasmic accumulation of Nrf2 can lead to the accumulation of lipid hydroperoxides and, ultimately, to ferroptosis. However, some studies aimed at elucidating the role of Nrf2 in non-cancer diseases have yielded conflicting results, attributed to differences in approaches used to inhibit or activate Nrf2, as well as variations in in vitro and/or in vivo disease models. Overall, these results highlight the necessity for a deeper evaluation of Nrf2's role in diseases, especially chronic diseases. In this review, we discuss diseases where Nrf2 inhibition holds potential for beneficial therapeutic effects and summarize recently reported Nrf2 inhibitors exploiting medicinal chemistry approaches suitable for targeting transcription factors like Nrf2.

Canagliflozin reverses doxorubicin-induced cardiotoxicity via restoration of autophagic homeostasis

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have been reported as successful for preventing doxorubicin (DOX) -induced cardiotoxicity (DIC), but the underlying mechanisms are elusive. This study aimed to determine whether canagliflozin, an SGLT2i, protects against DIC by regulation of autophagic flux in cardiomyocytes through a mechanism independent of SGLT2. The differentially expressed autophagy-related genes (ARGs) in DIC were analyzed. Neonatal rat cardiomyocytes (NRCMs), H9C2 rat cardiomyocytes or C57BL/6 mice were treated with canagliflozin or vehicle. The effects on cellular apoptosis and autophagy were investigated using qRT-PCR, western blotting and immunofluorescence. Additionally, cardiac function, myocardial fibrosis, and apoptosis of cardiomyocytes were also assessed in mice. The potential molecular targets of canagliflozin were identified through molecular docking analysis. A total of 26 differentially expressed ARGs were identified. Canagliflozin significantly activated autophagic flux and inhibited apoptosis of cardiomyocytes in both DOX-treated H9C2 rat cardiomyocytes and NRCMs. In a murine model of DIC, canagliflozin improved cardiac dysfunction by suppressing cardiac remodeling, fibrosis, and apoptosis. Moreover, canagliflozin promoted autophagy by enhancing SIRT1 levels and inhibiting the PI3K/Akt/mTOR signaling pathway. Immunofluorescence assays revealed that canagliflozin promoted the translocation of LC3 from the nucleus to the cytoplasm. Molecular docking analysis confirmed that canagliflozin has high affinity for targets associated with DIC. These findings suggest that canagliflozin protects cardiomyocytes from DOX-induced cell death by activating SIRT1, inhibiting the PI3K/Akt/mTOR pathway, and enhancing autophagic flux.