Canagliflozin mitigates ferroptosis and ameliorates heart failure in rats with preserved ejection fraction

Protocatechuic acid attenuates isoproterenol-induced heart failure by modulating cardiac oxidative stress, LDL-R/SREBP-2/PPAR-α, and Bax/Bcl-2 /Bcl-xL/Cyt.c/ Caspase - 9 and Caspase - 3 pathways

Worldwide, heart failure (HF) is among the top causes of morbidity and mortality. Curative interventions using natural products for cardiovascular diseases have gained substantial attention worldwide. At present, there is little research on the protective mechanisms of protocatechuic acid in HF. Hence, we evaluated the protective mechanisms of protocatechuic acid on cardiac oxidative stress, low-density lipoprotein-receptor (LDL-R)/sterol regulatory element-binding protein-2 (SREBP-2)/peroxisome proliferator-activated receptor-α(PPAR-α) and B-cell lymphoma-2 associated-x (Bax)/B-cell lymphoma gene-2(Bcl-2)/B-cell lymphoma-extra large(Bcl-xL)/Cytochrome c (Cyt.c)/Caspase-3/Caspase -9 pathways in isoproterenol-induced HF rats. Rats were induced HF by isoproterenol (5 mg/kg body weight) daily for 7 days. Then, rats were treated with protocatechuic acid (16 mg/kg body weight) for four weeks. The serum HF diagnostic marker and heart lipid hydroperoxides were increased and systolic and diastolic pressure and heart antioxidants were reduced in the isoproterenol-induced HF rats. Moreover, serum and heart total cholesterol, triglycerides, and serum low-density lipoprotein-cholesterol and liver 3-hydroxy-3 -methylglutaryl coenzyme A reductase were elevated and serum high density lipoprotein-cholesterol was reduced in the HF rats. Furthermore, lipid peroxidation products in the heart lysosomal fraction and lysosomal enzymes in the serum and heart were increased.A reverse transcription-polymerase chain reaction study revealed altered expression of hepatic LDL-R, SREBP-2, and PPAR- α and myocardial expression of Bax, Bcl-2, Bcl-xL, Cyt.c, Caspases-3, and -9 genes. Nevertheless, HF rats treated with protocatechuic acid considerably attenuated all the hemodynamic, biochemical, molecular, transmission electron microscopic, and histological parameters investigated and protected HF rats, by its potent antioxidant, anti-hyperlipidemic and anti-apoptotic mechanisms.

Mechanism of ferroptosis in heart failure: The role of the RAGE/TLR4-JNK1/2 pathway in cardiomyocyte ferroptosis and intervention strategies

The ferroptosis of cardiomyocytes has been recognized as the core pathological mechanism of heart failure. During the evolution of cardiovascular diseases, the accumulation of angiotensin II and advanced glycation end products can lead to the excessive activation of the RAGE/TLR4-JNK1/2 pathway, which subsequently triggers ferritinophagy, clockophagy, and enhanced p53 activity, ultimately leading to cardiomyocyte ferroptosis. It is evident that deeply unraveling the specific mechanisms in this field and comprehensively evaluating potential drugs and therapeutic strategies targeting this pathway is crucial for improving the status of cardiomyocyte ferroptosis. However, our current understanding of this pathway's specific molecular biological mechanisms in the process of cardiomyocyte ferroptosis remains limited. In light of this, this paper first comprehensively reviews the historical context of ferroptosis research, compares the similarities and differences between ferroptosis and other standard modes of cell death, elucidates the core mechanisms of ferroptosis and its close connection with heart failure, aiming to establish a basic cognitive framework for readers on ferroptosis and its role in heart failure. Subsequently, the paper delves into the pivotal role of the RAGE/TLR4-JNK1/2 pathway in cardiomyocyte ferroptosis and its intricate molecular biological regulatory network. Furthermore, it systematically integrates various therapeutic approaches aimed at inhibiting RAGE, TLR4, and JNK1/2 activity to alleviate cardiomyocyte ferroptosis, encompassing RNA interference technology, gene knockout techniques, small molecule inhibitors, natural active ingredients, as well as traditional Chinese and Western medicines, with the ultimate goal of forging new avenues and strategies for the prevention and treatment of heart failure.

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.

The alleviative effects of canagliflozin on imiquimod-induced mouse model of psoriasis-like inflammation

Psoriasis is a life-long immune-mediated dermatosis with thickened, reddish, and flaky skin patches. Canagliflozin is a gliflozin antidiabetic with non-classical remarkable antioxidative, anti-inflammatory, anti-proliferative, and immune-modulating effects. The aim of this study is to examine the probable effects of topical canagliflozin on a mouse model of imiquimod-provoked psoriasis-like dermatitis. The study evaluated 20 Swiss white mice, sorted haphazardly into 4 groups of 5 animals each. Every mouse, with the exception of the control group, had imiquimod applied topically to their shaved backs for 7 days. The control group included healthy mice that were not given any treatment. Mice in the other three groups underwent topical treatment with vehicle (induction group), 0.05% clobetasol propionate ointment (clobetasol group), or 4% canagliflozin emulgel (canagliflozin 4% group) on exactly the same day as imiquimod cream was administered. Topical canagliflozin markedly lowered the intensity of imiquimod-provoked psoriasis eruptions, featuring redness, glossy-white scales, and acanthosis, while also correcting histopathological aberrations. Canagliflozin administration to imiquimod-exposed animals resulted in significantly decreased cutaneous concentrations of inflammatory mediators such as IL-8, IL-17, IL-23, and TNF-α, with raised levels of IL-10. Canagliflozin further lowered proliferative factors involving Ki-67 and PCNA, diminished oxidative indicators such as MDA and MPO, and augmented the activity of antioxidant markers, notably SOD and CAT. Canagliflozin might alleviate the imiquimod-induced animal model of psoriasis, probably thanks to its profound anti-inflammatory, antioxidant, antiangiogenic, and antiproliferative activities.

Cardiac Fibrosis: Mechanistic Discoveries Linked to SGLT2 Inhibitors

Sodium-glucose cotransporter 2 inhibitors (SGLT2is), commonly known as flozins, have garnered attention not only for their glucose-lowering effects in type 2 diabetes mellitus (T2DM) but also for their cardioprotective properties. This review examines the mechanisms underlying the anti-fibrotic effects of SGLT2is, with a focus on key clinical trials and preclinical models. SGLT2is, mainly empagliflozin and dapagliflozin, have demonstrated significant reductions in heart failure-related hospitalizations, cardiovascular death, and fibrosis markers, independent of their glucose-lowering effects. The cardioprotective benefits appear to stem from direct actions on cardiac tissues, modulation of inflammatory responses, and improvements in metabolic parameters. In animal models of heart failure, SGLT2is were demonstrated to reduce cardiac fibrosis through mechanisms involving AMPK activation, reduced oxidative stress, and inhibition of pro-fibrotic pathways, not only through the inhibition of SGLT2 present on cardiac cells but also by targeting several other molecular targets. These findings confirm their efficacy in the treatment of heart failure and align with evidence from human trials, supporting the potential involvement of multiple pathways in mediating cardiac fibrosis. These results also provide a promising basis for clinical trials specifically targeting pathways shared with SGLT2is.

Molecular Mechanisms Underlying Heart Failure and Their Therapeutic Potential

Heart failure (HF) is a prominent fatal cardiovascular disorder afflicting 3.4% of the adult population despite the advancement of treatment options. Therefore, a better understanding of the pathogenesis of HF is essential for exploring novel therapeutic strategies. Hypertrophy and fibrosis are significant characteristics of pathological cardiac remodeling, contributing to HF. The mechanisms involved in the development of cardiac remodeling and consequent HF are multifactorial, and in this review, the key underlying mechanisms are discussed. These have been divided into the following categories thusly: (i) mitochondrial dysfunction, including defective dynamics, energy production, and oxidative stress; (ii) cardiac lipotoxicity; (iii) maladaptive endoplasmic reticulum (ER) stress; (iv) impaired autophagy; (v) cardiac inflammatory responses; (vi) programmed cell death, including apoptosis, pyroptosis, and ferroptosis; (vii) endothelial dysfunction; and (viii) defective cardiac contractility. Preclinical data suggest that there is merit in targeting the identified pathways; however, their clinical implications and outcomes regarding treating HF need further investigation in the future. Herein, we introduce the molecular mechanisms pivotal in the onset and progression of HF, as well as compounds targeting the related mechanisms and their therapeutic potential in preventing or rescuing HF. This, therefore, offers an avenue for the design and discovery of novel therapies for the treatment of HF.

Canagliflozin ameliorates ferritinophagy in HFpEF rats

Background

Recent studies have shown that sodium-glucose cotransporters-2 (SGLT2) inhibitors significantly improve major adverse cardiovascular events in heart failure with preserved ejection fraction (HFpEF) patients, but the exact mechanism is unknown. Ferritinophagy is a special form of selective autophagy that participates in ferroptosis. In this study, we aimed to investigate whether ferritinophagy was activated during the occurrence of HFpEF, and whether canagliflozin (CANA) could inhibite ferritinophagy.

Methods

We reared Dahl salt-sensitive (DSS) rats on a high-salt diet to construct a hypertensive HFpEF model, and simultaneously administered CANA intervention. Then we detected indicators related to ferritinophagy.

Results

The expression of nuclear receptor coactivator 4 (NCOA4), as well as microtubule-associated proteins light chain 3 (LC3), Bcl-2 interacting protein 1 (Beclin-1) and p62, were upregulated in HFpEF rats, accompanied by the downregulation of ferritin heavy chain 1 (FTH1), upregulation of mitochondrial iron transporter sideroflexin1 (SFXN1) and increased reactive oxygen species (ROS) production. Above changes were diminished by CANA.

CONCLUSION

Ferritinophagy is activated in HFpEF rats and then inhibited by CANA, leading to HFpEF benefits. The inhibition of ferritinophagy could provide new prospective targets for the prevention and treatment of HFpEF, and provide new ideas for investigating the mechanism of cardiovascular benefit of SGLT2 inhibitors.

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.

SGLT2 Inhibitors in Patients with Heart Failure: A Model-Based Meta-Analysis

AIMS

This study aimed to quantify the effects of sodium-glucose co-transporter 2 (SGLT2) inhibitors on N-terminal pro-B-type natriuretic peptide (NT-proBNP) as a therapeutic approach for heart failure.

METHODS

A systematic literature review was conducted to collect pharmacokinetics (PK) and pharmacodynamics (PD) data on empagliflozin, dapagliflozin, and canagliflozin. Population pharmacokinetic models were developed separately for each drug, along with PK/PD turnover models for SGLT2 inhibitors, to describe the time course of NT-proBNP and simulate its changes over 52 weeks.

RESULTS

A total of 42 publications were included in this study. The results showed that baseline NT-proBNP levels, estimated glomerular filtration rate levels, and body weight significantly influenced the therapeutic effects of SGLT2 inhibitors. Among the studied drugs, canagliflozin demonstrated a greater reduction in NT-proBNP at comparable baseline levels.

CONCLUSIONS

Baseline NT-proBNP concentration, renal function, and body weight were covariates affecting the efficacy of SGLT2 inhibitors in reducing NT-proBNP. Canagliflozin showed the most favorable treatment outcomes at similar baseline levels. This model-based meta-analysis approach may support further drug development for SGLT2 inhibitors.

Sodium-Glucose Cotransporter 2 (SGLT2) Inhibitors: Guardians against Mitochondrial Dysfunction and Endoplasmic Reticulum Stress in Heart Diseases

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are an innovative class of antidiabetic drugs that provide cardiovascular benefits to both diabetic and nondiabetic patients, surpassing those of other antidiabetic drugs. Although the roles of mitochondria and endoplasmic reticulum (ER) in cardiovascular research are increasingly recognized as promising therapeutic targets, the exact molecular mechanisms by which SGLT2 inhibitors influence mitochondrial and ER homeostasis in the heart remain incompletely elucidated. This review comprehensively summarizes and discusses the impacts of SGLT2 inhibitors on mitochondrial dysfunction and ER stress in heart diseases including heart failure, ischemic heart disease/myocardial infarction, and arrhythmia from preclinical and clinical studies. Based on the existing evidence, the effects of SGLT2 inhibitors may potentially involve the restoration of mitochondrial biogenesis and alleviation of ER stress. Such consequences are achieved by enhancing adenosine triphosphate (ATP) production, preserving mitochondrial membrane potential, improving the activity of electron transport chain complexes, maintaining mitochondrial dynamics, mitigating oxidative stress and apoptosis, influencing cellular calcium and sodium handling, and targeting the unfolded protein response (UPR) through three signaling pathways including inositol requiring enzyme 1α (IRE1α), protein kinase R like endoplasmic reticulum kinase (PERK), and activating transcription factor 6 (ATF6). Therefore, SGLT2 inhibitors have emerged as a promising target for treating heart diseases due to their potential to improve mitochondrial functions and ER stress.

Effects of empagliflozin and dapagliflozin on serum humanin, MOTS-c levels, nitrosative stress, and ferroptosis parameters in diabetic patients with heart failure

Sodium-glucose cotransporter 2 (SGLT2) inhibitors produce cardioprotective effects on heart failure (HF), even in the absence of diabetes. However, the underlying mechanisms of this cardioprotective effect remain unexplored. The purpose of this study was to examine the effects of SGLT2 inhibitors on serum MOTS-c, humanin levels, nitrosative stress, and ferroptosis parameters in diabetic patients with HF with reduced ejection fraction (HFrEF). A total of 74 adult diabetic patients with HFrEF and 37 healthy controls were included in this prospective study. Half of the patients were using SGLT2 inhibitors (empagliflozin or dapagliflozin) for at least two months. Serum nitric oxide and 3-nitrotyrosine levels were markedly higher in diabetic patients with HFrEF than the control (P < 0.001), but these elevations were inhibited with SGLT2 inhibitors. Although SGLT2 inhibitors had no marked effect on humanin levels, they significantly augmented MOTS-c levels when compared to the control. SGLT2 inhibitors augmented GPX4 but inhibited ACSL4 levels when compared to diabetic patients with HF. However, TFRC levels were increased in the patient group (P < 0.001 for all) but not modified with SGLT2 inhibitors. Our results suggest that increased nitrosative stress is significantly depressed by SGLT2 inhibitors. This study was the first to show that SGLT2 inhibitors can stimulate MOTS-c, but not humanin, in diabetic patients with HFrEF. SGLT2 inhibitors reduced ferroptosis through elevation of GPX4 and suppression of ACSL4 levels. Our data suggest that SGLT2 inhibitors could produce cardioprotective effects through relieving ferroptosis, inhibiting nitosative stress, and stimulating mitochondrial MOTS-c release.

Sodium-Glucose Co-Transporter-2 Inhibitor Empagliflozin Attenuates Sorafenib-Induced Myocardial Inflammation and Toxicity

Environmental antineoplastics such as sorafenib may pose a risk to humans through water recycling, and the increased risk of cardiotoxicity is a clinical issue in sorafenib users. Thus, developing strategies to prevent sorafenib cardiotoxicity is an urgent work. Empagliflozin, as a sodium-glucose co-transporter-2 (SGLT2) inhibitor for type 2 diabetes control, has been approved for heart failure therapy. Still, its cardioprotective effect in the experimental model of sorafenib cardiotoxicity has not yet been reported. Real-time quantitative RT-PCR (qRT-PCR), immunoblot, and immunohistochemical analyses were applied to study the effect of sorafenib exposure on cardiac SGLT2 expression. The impact of empagliflozin on cell viability was investigated in the sorafenib-treated cardiomyocytes using Alamar blue assay. Immunoblot analysis was employed to delineate the effect of sorafenib and empagliflozin on ferroptosis/proinflammatory signaling in cardiomyocytes. Ferroptosis/DNA damage/fibrosis/inflammation of myocardial tissues was studied in mice with a 28-day sorafenib ± empagliflozin treatment using histological analyses. Sorafenib exposure significantly promoted SGLT2 upregulation in cardiomyocytes and mouse hearts. Empagliflozin treatment significantly attenuated the sorafenib-induced cytotoxicity/DNA damage/fibrosis in cardiomyocytes and mouse hearts. Moreover, GPX4/xCT-dependent ferroptosis as an inducer for releasing high mobility group box 1 (HMGB1) was also blocked by empagliflozin administration in the sorafenib-treated cardiomyocytes and myocardial tissues. Furthermore, empagliflozin treatment significantly inhibited the sorafenib-promoted NFκB/HMGB1 axis in cardiomyocytes and myocardial tissues, and sorafenib-stimulated proinflammatory signaling (TNF-α/IL-1β/IL-6) was repressed by empagliflozin administration. Finally, empagliflozin treatment significantly attenuated the sorafenib-promoted macrophage recruitments in mouse hearts. In conclusion, empagliflozin may act as a cardioprotective agent for humans under sorafenib exposure by modulating ferroptosis/DNA damage/fibrosis/inflammation. However, further clinical evidence is required to support this preclinical finding.

New insights into the cardio-renal benefits of SGLT2 inhibitors and the coordinated role of miR-30 family

Sodium-glucose co-transporter inhibitors (SGLTis) are the latest class of anti-hyperglycemic agents. In addition to inhibiting the absorption of glucose by the kidney causing glycosuria, these drugs also demonstrate cardio-renal benefits in diabetic subjects. miR-30 family, one of the most abundant microRNAs in the heart, has recently been linked to a setting of cardiovascular diseases and has been proposed as novel biomarkers in kidney dysfunctions as well; their expression is consistently dysregulated in a variety of cardio-renal dysfunctions. The mechanistic involvement and the potential interplay between miR-30 and SGLT2i effects have yet to be thoroughly elucidated. Recent research has stressed the relevance of this cluster of microRNAs as modulators of several pathological processes in the heart and kidneys, raising the possibility of these small ncRNAs playing a central role in various cardiovascular complications, notably, endothelial dysfunction and pathological remodeling. Here, we review current evidence supporting the pleiotropic effects of SGLT2is in cardiovascular and renal outcomes and investigate the link and the coordinated implication of the miR-30 family in endothelial dysfunction and cardiac remodeling. We also discuss the emerging role of circulating miR-30 as non-invasive biomarkers and attractive therapeutic targets for cardiovascular diseases and kidney diseases. Clinical evidence, as well as metabolic, cellular, and molecular aspects, are comprehensively covered.

Cardioprotection of Canagliflozin, Dapagliflozin, and Empagliflozin: Lessons from preclinical studies

Clinical and preclinical studies have elucidated the favorable effects of Inhibitors of Sodium-Glucose Cotransporter-2 (iSGLT2) in patients and animal models with type 2 diabetes. Notably, these inhibitors have shown significant benefits in reducing hospitalizations and mortality among patients with heart failure. However, despite their incorporation into clinical practice for indications beyond diabetes, the decision-making process regarding their use often lacks a systematic approach. The selection of iSGLT2 remains arbitrary, with only a limited number of studies simultaneously exploring the different classes of them. Currently, no unique guideline establishes their application in both clinical and basic research. This review delves into the prevalent use of iSGLT2 in animal models previously subjected to induced cardiac stress. We have compiled key findings related to cardioprotection across various animal models, encompassing diverse dosages and routes of administration. Beyond their established role in diabetes management, iSGLT2 has demonstrated utility as agents for safeguarding heart health and cardioprotection can be class-dependent among the iSGLT2. These findings may serve as valuable references for other researchers. Preclinical studies play a pivotal role in ensuring the safety of novel compounds or treatments for potential human use. By assessing side effects, toxicity, and optimal dosages, these studies offer a robust foundation for informed decisions, identifying interventions with the highest likelihood of success and minimal risk to patients. The insights gleaned from preclinical studies, which play a crucial role in highlighting areas of knowledge deficiency, can guide the exploration of novel mechanisms and strategies involving iSGLT2.

Ex vivo modelling of cardiac injury identifies ferroptosis-related pathways as a potential therapeutic avenue for translational medicine

BACKGROUND

Heart failure (HF) is a burgeoning health problem worldwide. Often arising as a result of cardiac injury, HF has become a major cause of mortality with limited availability of effective treatments. Ferroptotic pathways, triggering an iron-dependent form of cell death, are known to be potential key players in heart disease. This form of cell death does not exhibit typical characteristics of programmed cell death, and is mediated by impaired iron metabolism and lipid peroxidation signalling.

OBJECTIVES

The aim of this study is to establish an ex-vivo model of myocardial injury in living myocardial slices (LMS) and to identify novel underlying mechanisms and potential therapeutic druggable target(s).

METHODS AND RESULTS

In this study, we employed LMS as an ex vivo model of cardiac injury to investigate underlying mechanisms and potential therapeutic targets. Cryoinjury was induced in adult rat LMS, resulting in 30 % tissue damage. Cryoinjured LMS demonstrated impaired contractile function, cardiomyocyte hypertrophy, inflammation, and cardiac fibrosis, closely resembling in vivo cardiac injury characteristics. Proteomic analysis revealed an enrichment of factors associated with ferroptosis in the injured LMS, suggesting a potential causative role. To test this hypothesis, we pharmacologically inhibited ferroptotic pathways using ferrostatin (Fer-1) in the cryoinjured rat LMS, resulting in attenuation of structural changes and repression of pro-fibrotic processes. Furthermore, LMS generated from failing human hearts were used as a model of chronic heart failure. In this model, Fer-1 treatment was observed to reduce the expression of ferroptotic genes, enhances contractile function and improves tissue viability. Blocking ferroptosis-associated pathways in human cardiac fibroblasts (HCFs) resulted in a downregulation of fibroblast activation genes, a decrease in fibroblast migration capacity, and a reduction in reactive oxygen species production. RNA sequencing analysis of Fer-1-treated human LMS implicated metallothioneins as a potential underlying mechanism for the inhibition of these pathways. This effect is possibly mediated through the replenishment of glutathione reserves.

CONCLUSIONS

Our findings highlight the potential of targeting ferroptosis-related pathways and metallothioneins as a promising strategy for the treatment of heart disease.

Iron homeostasis and ferroptosis in human diseases: mechanisms and therapeutic prospects

Iron, an essential mineral in the body, is involved in numerous physiological processes, making the maintenance of iron homeostasis crucial for overall health. Both iron overload and deficiency can cause various disorders and human diseases. Ferroptosis, a form of cell death dependent on iron, is characterized by the extensive peroxidation of lipids. Unlike other kinds of classical unprogrammed cell death, ferroptosis is primarily linked to disruptions in iron metabolism, lipid peroxidation, and antioxidant system imbalance. Ferroptosis is regulated through transcription, translation, and post-translational modifications, which affect cellular sensitivity to ferroptosis. Over the past decade or so, numerous diseases have been linked to ferroptosis as part of their etiology, including cancers, metabolic disorders, autoimmune diseases, central nervous system diseases, cardiovascular diseases, and musculoskeletal diseases. Ferroptosis-related proteins have become attractive targets for many major human diseases that are currently incurable, and some ferroptosis regulators have shown therapeutic effects in clinical trials although further validation of their clinical potential is needed. Therefore, in-depth analysis of ferroptosis and its potential molecular mechanisms in human diseases may offer additional strategies for clinical prevention and treatment. In this review, we discuss the physiological significance of iron homeostasis in the body, the potential contribution of ferroptosis to the etiology and development of human diseases, along with the evidence supporting targeting ferroptosis as a therapeutic approach. Importantly, we evaluate recent potential therapeutic targets and promising interventions, providing guidance for future targeted treatment therapies against human diseases.

Targeting the Sirtuin-1/PPAR-Gamma Axis, RAGE/HMGB1/NF-κB Signaling, and the Mitochondrial Functions by Canagliflozin Augments the Protective Effects of Levodopa/Carbidopa in Rotenone-Induced Parkinson's Disease

Background and Objectives: Parkinson's disease (PD) is a pathological state characterized by a combined set of abnormal movements including slow motion, resting tremors, profound stiffness of skeletal muscles, or obvious abnormalities in posture and gait, together with significant behavioral changes. Until now, no single therapeutic modality was able to provide a complete cure for PD. This work was a trial to assess the immunomodulatory effects of canagliflozin with or without levodopa/carbidopa on rotenone-induced parkinsonism in Balb/c mice. Materials and Methods: In a mouse model of PD, the effect of canagliflozin with or without levodopa/carbidopa was assessed at the behavioral, biochemical, and histopathological levels. Results: The combination of levodopa/carbidopa and canagliflozin significantly mitigated the changes induced by rotenone administration regarding the behavioral tests, striatal dopamine, antioxidant status, Nrf2 content, SIRT-1/PPAR-gamma axis, RAGE/HMGB1/NF-κB signaling, and mitochondrial dysfunction; abrogated the neuroinflammatory responses, and alleviated the histomorphologic changes induced by rotenone administration relative to the groups that received either levodopa/carbidopa or canagliflozin alone. Conclusions: Canagliflozin may represent a new adjuvant therapeutic agent that may add value to the combatting effects of levodopa/carbidopa against the pathological effects of PD.

The Role of Programmed Types of Cell Death in Pathogenesis of Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a condition that develops in the course of many diseases and conditions, and its pathophysiology is still not well understood, but the involvement of programmed types of cell death in the development of this type of heart failure is becoming increasingly certain. In addition, drugs already widely used in clinical practice, with a good safety profile and efficacy demonstrated in large-group clinical trials, seem to be exerting their beneficial effects on cardiovascular health. Perhaps new drugs that reduce the susceptibility of cells to programmed types of cell death are under investigation and may improve the prognosis of patients with HFpEF. In this article, we summarize the current knowledge about the pathogenesis of HFpEF and the role of programmed types of cell death in its development. Additionally, we have described the future directions of research that may lead to the improvement of a patient's prognosis and potential treatment.

Role of ferroptosis in the pathogenesis of heart disease

Ferroptosis is a new form of regulated necrosis characterized by iron-dependent lipid peroxidation, leading to irreparable lipid damage, membrane permeabilization, and necrotic cell death. Ferroptosis has recently been implicated in the pathogenesis of multiple forms of heart disease such as myocardial infarction, cardiac hypertrophy, heart failure, and various cardiomyopathies. Important progress has also been made regarding how ferroptosis is regulated in vitro and in vivo as well as its role in cardiac homeostasis and disease pathogenesis. In this review, we discuss molecular mechanisms that regulates ferroptosis in the heart, including pathways leading to iron overload and lipid peroxidation as well as the roles of key organelles in this process. We also discuss recent findings pertaining to the new pathogenic role of ferroptosis in various forms of heart disease as well as genetic and pharmacologic strategies targeting ferroptosis in the heart.

Mechanisms of heart failure and chronic kidney disease protection by SGLT2 inhibitors in nondiabetic conditions

Sodium-glucose cotransporter 2 inhibitors (SGLT2is), initially developed for type 2 diabetes (T2D) treatment, have demonstrated significant cardiovascular and renal benefits in heart failure (HF) and chronic kidney disease (CKD), irrespective of T2D. This review provides an analysis of the multifaceted mechanisms underlying the cardiorenal benefits of SGLT2i in HF and CKD outside of the T2D context. Eight major aspects of the protective effects of SGLT2i beyond glycemic control are explored: 1) the impact on renal hemodynamics and tubuloglomerular feedback; 2) the natriuretic effects via proximal tubule Na+/H+ exchanger NHE3 inhibition; 3) the modulation of neurohumoral pathways with evidence of attenuated sympathetic activity; 4) the impact on erythropoiesis, not only in the context of local hypoxia but also systemic inflammation and iron regulation; 5) the uricosuria and mitigation of the hyperuricemic environment in cardiorenal syndromes; 6) the multiorgan metabolic reprogramming including the potential induction of a fasting-like state, improvement in glucose and insulin tolerance, and stimulation of lipolysis and ketogenesis; 7) the vascular endothelial growth factor A (VEGF-A) upregulation and angiogenesis, and 8) the direct cardiac effects. The intricate interplay between renal, neurohumoral, metabolic, and cardiac effects underscores the complexity of SGLT2i actions and provides valuable insights into their therapeutic implications for HF and CKD. Furthermore, this review sets the stage for future research to evaluate the individual contributions of these mechanisms in diverse clinical settings.

Ferroptosis and iron metabolism in diabetes: Pathogenesis, associated complications, and therapeutic implications

Diabetes mellitus is a complex chronic disease, considered as one of the most common metabolic disorders worldwide, posing a major threat to global public health. Ferroptosis emerges as a novel mechanism of programmed cell death, distinct from apoptosis, necrosis, and autophagy, driven by iron-dependent lipid peroxidation accumulation and GPx4 downregulation. A mounting body of evidence highlights the interconnection between iron metabolism, ferroptosis, and diabetes pathogenesis, encompassing complications like diabetic nephropathy, cardiomyopathy, and neuropathy. Moreover, ferroptosis inhibitors hold promise as potential pharmacological targets for mitigating diabetes-related complications. A better understanding of the role of ferroptosis in diabetes may lead to an improvement in global diabetes management. In this review, we delve into the intricate relationship between ferroptosis and diabetes development, exploring associated complications and current pharmacological treatments.

The potential anti-arrhythmic effect of SGLT2 inhibitors

Sodium-glucose cotransporter type 2 inhibitors (SGLT2i) were initially recommended as oral anti-diabetic drugs to treat type 2 diabetes (T2D), by inhibiting SGLT2 in proximal tubule and reduce renal reabsorption of sodium and glucose. While many clinical trials demonstrated the tremendous potential of SGLT2i for cardiovascular diseases. 2022 AHA/ACC/HFSA guideline first emphasized that SGLT2i were the only drug class that can cover the entire management of heart failure (HF) from prevention to treatment. Subsequently, the antiarrhythmic properties of SGLT2i have also attracted attention. Although there are currently no prospective studies specifically on the anti-arrhythmic effects of SGLT2i. We provide clues from clinical and fundamental researches to identify its antiarrhythmic effects, reviewing the evidences and mechanism for the SGLT2i antiarrhythmic effects and establishing a novel paradigm involving intracellular sodium, metabolism and autophagy to investigate the potential mechanisms of SGLT2i in mitigating arrhythmias.

The Off-Target Cardioprotective Mechanisms of Sodium-Glucose Cotransporter 2 Inhibitors: An Overview

Sodium-glucose cotransporter 2 inhibitors (SGLT2i), a novel class of glucose-lowering drugs, have revolutionized the management of heart failure with reduced and preserved ejection fraction, regardless of the presence of diabetes, and are currently incorporated in the heart failure guidelines. While these drugs have consistently demonstrated their ability to decrease heart failure hospitalizations in several landmark clinical trials, their cardioprotective effects are far from having been completely elucidated. In the past decade, a growing body of experimental research has sought to address the molecular and cellular mechanisms of SGLT2i in order to provide a better understanding of the off-target acute and chronic cardiac benefits, beyond the on-target renal effect responsible for blood glucose reduction. The present narrative review addresses the direct cardioprotective effects of SGLT2i, delving into the off-target mechanisms of the drugs currently approved for heart failure therapy, and provides insights into future perspectives.

Distinct Profiles and New Pharmacological Targets for Heart Failure with Preserved Ejection Fraction

Background

Heart failure with preserved ejection fraction (HFpEF) is a multifactorial condition with a variety of pathophysiological causes and morphological manifestations. The inclusion criteria and patient classification have become overly simplistic due to the customary differentiation regarding the ejection fraction (EF) cutoff. EF is considered a measure of systolic function; nevertheless, it only represents a portion of the true contractile state and has been shown to have certain limits due to methodological and hemodynamic irregularities.

Methods

As a result, broader randomized clinical trials have yet to incorporate the most recent criteria for HFpEF diagnosis, leading to a lack of data consistency and confusion in interpreting the results. The primary variations between the bigger clinical trials published in this context concerning patient selection and echocardiographic characteristics were analyzed. For all these reasons, we aim to clarify the main features and clinical impact of HFpEF in a study combining imaging, bio-humoral analysis, and clinical history to identify the specific subgroups that respond better to tailored treatment.

Results

Disparate clinical characteristics and a lack of uniform diagnostic standards may cause suboptimal therapeutic feedback. To optimize treatment, we suggest shifting the paradigm from the straightforward EF measurement to a more comprehensive model that considers additional information, such as structural traits, related disorders, and biological and environmental data. Therefore, by evaluating certain echocardiographic and clinical factors, a stepwise diagnostic procedure may be useful in identifying patients at high risk, subjects with early HFpEF, and those with evident HFpEF.

Conclusions

The present assessment underscores the significance of the precision medicine approach in guaranteeing optimal patient outcomes by providing the best care according to each distinct profile.

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.

Empagliflozin, a sodium-glucose cotransporter inhibitor enhancing mitochondrial action and cardioprotection in metabolic syndrome

Metabolic syndrome (MetS) has a large clinical population nowadays, usually due to excessive energy intake and lack of exercise. During MetS, excess nutrients stress the mitochondria, resulting in relative hypoxia in tissues and organs, even when blood supply is not interrupted or reduced, making mitochondrial dysfunction a central pathogenesis of cardiovascular disease in the MetS. Sodium-glucose cotransporter 2 inhibitors were designed as a hyperglycemic drug that acts on the renal tubules to block sugar reabsorption in primary urine. Recently they have been shown to have anti-inflammatory and other protective effects on cardiomyocytes in MetS, and have also been recommended in the latest heart failure guidelines as a routine therapy. Among these inhibitors, empagliflozin shows better clinical promise due to less influence from glomerular filtration rate. This review focuses on the mitochondrial mechanisms of empagliflozin, which underlie the anti-inflammatory and recover cellular functions in MetS cardiomyocytes, including stabilizing calcium concentration, mediating metabolic reprogramming, maintaining homeostasis of mitochondrial quantity and quality, stable mitochondrial DNA copy number, and repairing damaged mitochondrial DNA.

Role and molecular mechanisms of SGLT2 inhibitors in pathological cardiac remodeling (Review)

Cardiovascular diseases are caused by pathological cardiac remodeling, which involves fibrosis, inflammation and cell dysfunction. This includes autophagy, apoptosis, oxidative stress, mitochondrial dysfunction, changes in energy metabolism, angiogenesis and dysregulation of signaling pathways. These changes in heart structure and/or function ultimately result in heart failure. In an effort to prevent this, multiple cardiovascular outcome trials have demonstrated the cardiac benefits of sodium‑glucose cotransporter type 2 inhibitors (SGLT2is), hypoglycemic drugs initially designed to treat type 2 diabetes mellitus. SGLT2is include empagliflozin and dapagliflozin, which are listed as guideline drugs in the 2021 European Guidelines for Heart Failure and the 2022 American Heart Association/American College of Cardiology/Heart Failure Society of America Guidelines for Heart Failure Management. In recent years, multiple studies using animal models have explored the mechanisms by which SGLT2is prevent cardiac remodeling. This article reviews the role of SGLT2is in cardiac remodeling induced by different etiologies to provide a guideline for further evaluation of the mechanisms underlying the inhibition of pathological cardiac remodeling by SGLT2is, as well as the development of novel drug targets.

Research advances on molecular mechanism and natural product therapy of iron metabolism in heart failure

The progression of heart failure (HF) is complex and involves multiple regulatory pathways. Iron ions play a crucial supportive role as a cofactor for important proteins such as hemoglobin, myoglobin, oxidative respiratory chain, and DNA synthetase, in the myocardial energy metabolism process. In recent years, numerous studies have shown that HF is associated with iron dysmetabolism, and deficiencies in iron and overload of iron can both lead to the development of various myocarditis diseases, which ultimately progress to HF. Iron toxicity and iron metabolism may be key targets for the diagnosis, treatment, and prevention of HF. Some iron chelators (such as desferrioxamine), antioxidants (such as ascorbate), Fer-1, and molecules that regulate iron levels (such as lactoferrin) have been shown to be effective in treating HF and protecting the myocardium in multiple studies. Additionally, certain natural compounds can play a significant role by mediating the imbalance of iron-related signaling pathways and expression levels. Therefore, this review not only summarizes the basic processes of iron metabolism in the body and the mechanisms by which they play a role in HF, with the aim of providing new clues and considerations for the treatment of HF, but also summarizes recent studies on natural chemical components that involve ferroptosis and its role in HF pathology, as well as the mechanisms by which naturally occurring products regulate ferroptosis in HF, with the aim of providing reference information for the development of new ferroptosis inhibitors and lead compounds for the treatment of HF in the future.

The Cardioprotective and Anticancer Effects of SGLT2 Inhibitors: JACC: CardioOncology State-of-the-Art Review

Sodium-glucose cotransporter-2 (SGLT2) inhibitors, originally approved for type 2 diabetes mellitus, have demonstrated efficacy in reducing cardiovascular events, particularly heart failure, in patients with and without diabetes. An intriguing research area involves exploring the potential application of SGLT2 inhibitors in cardio-oncology, aiming to mitigate the cardiovascular adverse events associated with anticancer treatments. These inhibitors present a unique dual nature, offering both cardioprotective effects and anticancer properties, conferring a double benefit for cardio-oncology patients. In this review, the authors first examine the established cardioprotective effects of SGLT2 inhibitors in heart failure and subsequently explore the existing body of evidence, including both preclinical and clinical studies, that supports the use of SGLT2 inhibitors in the context of cardio-oncology. The authors further discuss the mechanisms through which SGLT2 inhibitors protect against cardiovascular toxicity secondary to cancer treatment. Finally, they explore the potential anticancer effects of SGLT2 inhibitors along with their proposed mechanisms.

The role of ferroptosis in cardio-oncology

With the rapid development of new generations of antitumor therapies, the average survival time of cancer patients is expected to be continuously prolonged. However, these therapies often lead to cardiotoxicity, resulting in a growing number of tumor survivors with cardiovascular disease. Therefore, a new interdisciplinary subspecialty called "cardio-oncology" has emerged, aiming to detect and treat cardiovascular diseases associated with tumors and antitumor therapies. Recent studies have highlighted the role of ferroptosis in both cardiovascular and neoplastic diseases. The balance between intracellular oxidative stress and antioxidant defense is crucial in regulating ferroptosis. Tumor cells can evade ferroptosis by upregulating multiple antioxidant defense pathways, while many antitumor therapies rely on downregulating antioxidant defense and promoting ferroptosis in cancer cells. Unfortunately, these ferroptosis-inducing antitumor therapies often lack tissue specificity and can also cause injury to the heart, resulting in ferroptosis-induced cardiotoxicity. A range of cardioprotective agents exert cardioprotective effects by inhibiting ferroptosis. However, these cardioprotective agents might diminish the efficacy of antitumor treatment due to their antiferroptotic effects. Most current research on ferroptosis only focuses on either tumor treatment or heart protection but rarely considers both in concert. Therefore, further research is needed to study how to protect the heart during antitumor therapies by regulating ferroptosis. In this review, we summarized the role of ferroptosis in the treatment of neoplastic diseases and cardiovascular diseases and also attempted to propose further research directions for ferroptosis in the field of cardio-oncology.

Ferroptosis, a Regulated Form of Cell Death, as a Target for the Development of Novel Drugs Preventing Ischemia/Reperfusion of Cardiac Injury, Cardiomyopathy and Stress-Induced Cardiac Injury

The hospital mortality in patients with ST-segment elevation myocardial infarction (STEMI) is about 6% and has not decreased in recent years. The leading cause of death of these patients is ischemia/reperfusion (I/R) cardiac injury. It is quite obvious that there is an urgent need to create new drugs for the treatment of STEMI based on knowledge about the pathogenesis of I/R cardiac injury, in particular, based on knowledge about the molecular mechanism of ferroptosis. In this study, it was demonstrated that ferroptosis is involved in the development of I/R cardiac injury, antitumor drug-induced cardiomyopathy, diabetic cardiomyopathy, septic cardiomyopathy, and inflammation. There is indirect evidence that ferroptosis participates in stress-induced cardiac injury. The activation of AMPK, PKC, ERK1/2, PI3K, and Akt prevents myocardial ferroptosis. The inhibition of HO-1 alleviates myocardial ferroptosis. The roles of GSK-3β and NOS in the regulation of ferroptosis require further study. The stimulation of Nrf2, STAT3 prevents ferroptosis. The activation of TLR4 and NF-κB promotes ferroptosis of cardiomyocytes. MiR-450b-5p and miR-210-3p can increase the tolerance of cardiomyocytes to hypoxia/reoxygenation through the inhibition of ferroptosis. Circ_0091761 RNA, miR-214-3p, miR-199a-5p, miR-208a/b, miR-375-3p, miR-26b-5p and miR-15a-5p can aggravate myocardial ferroptosis.

Emerging roles and therapeutic potentials of ferroptosis: from the perspective of 11 human body organ systems

Since ferroptosis was first described as an iron-dependent cell death pattern in 2012, there has been increasing interest in ferroptosis research. In view of the immense potential of ferroptosis in treatment efficacy and its rapid development in recent years, it is essential to track and summarize the latest research in this field. However, few writers have been able to draw on any systematic investigation into this field based on human body organ systems. Hence, in this review, we provide a comprehensive description of the latest progress in unveiling the roles and functions, as well as the therapeutic potential of ferroptosis, in treating diseases from the aspects of 11 human body organ systems (including the nervous system, respiratory system, digestive system, urinary system, reproductive system, integumentary system, skeletal system, immune system, cardiovascular system, muscular system, and endocrine system) in the hope of providing references for further understanding the pathogenesis of related diseases and bringing an innovative train of thought for reformative clinical treatment.

Ferroptosis in cardiac hypertrophy and heart failure

Heart failure has become a public health problem that we cannot avoid choosing to face in today's context. In the case of heart failure, pathological cardiac hypertrophy plays a major role because of its condition of absolute increase in ventricular mass under various stresses. Ferroptosis, it could be defined as regulatory mechanisms that regulate cell death in the absence of apoptosis in iron-dependent cells. This paper introduces various new research findings on the use of different regulatory mechanisms of cellular ferroptosis for the treatment of heart failure and cardiac hypertrophy, providing new therapeutic targets and research directions for clinical treatment. The role and mechanism of ferroptosis in the field of heart failure has been increasingly demonstrated, and the relationship between cardiac hypertrophy, which is one of the causes of heart failure, is also an area of research that we should focus on. In addition, the latest applications and progress of inducers and inhibitors of ferroptosis are reported in this paper, updating the breakthroughs in their fields.

Metabolic dysfunction-associated steatotic liver disease: ferroptosis related mechanisms and potential drugs

Metabolic dysfunction-associated steatotic liver disease (MASLD) is considered a "multisystem" disease that simultaneously suffers from metabolic diseases and hepatic steatosis. Some may develop into liver fibrosis, cirrhosis, and even hepatocellular carcinoma. Given the close connection between metabolic diseases and fatty liver, it is urgent to identify drugs that can control metabolic diseases and fatty liver as a whole and delay disease progression. Ferroptosis, characterized by iron overload and lipid peroxidation resulting from abnormal iron metabolism, is a programmed cell death mechanism. It is an important pathogenic mechanism in metabolic diseases or fatty liver, and may become a key direction for improving MASLD. In this article, we have summarized the physiological and pathological mechanisms of iron metabolism and ferroptosis, as well as the connections established between metabolic diseases and fatty liver through ferroptosis. We have also summarized MASLD therapeutic drugs and potential active substances targeting ferroptosis, in order to provide readers with new insights. At the same time, in future clinical trials involving subjects with MASLD (especially with the intervention of the therapeutic drugs), the detection of serum iron metabolism levels and ferroptosis markers in patients should be increased to further explore the efficacy of potential drugs on ferroptosis.

Current progress of ferroptosis in cardiovascular diseases

Ferroptosis, a newly recognized form of nonapoptotic regulated cell death, is characterized by iron-dependent lipid peroxidation. Biological processes, such as iron metabolism, lipid peroxidation, and amino acid metabolism, are involved in the process of ferroptosis. However, the related molecular mechanism of ferroptosis has not yet been completely clarified, and specific and sensitive biomarkers for ferroptosis need to be explored. Recently, studies have revealed that ferroptosis probably causes or exacerbates the progress of cardiovascular diseases, and could be the potential therapeutic target for cardiovascular diseases. In this review, we summarize the molecular mechanisms regulating ferroptosis, inducers or inhibitors of ferroptosis, and the current progresses of ferroptosis in cardiovascular diseases. Furthermore, we discuss the emerging challenges and future perspectives, which may provide novel insights into the treatment of cardiovascular diseases.

The mechanism of ferroptosis and its related diseases

Ferroptosis, a regulated form of cellular death characterized by the iron-mediated accumulation of lipid peroxides, provides a novel avenue for delving into the intersection of cellular metabolism, oxidative stress, and disease pathology. We have witnessed a mounting fascination with ferroptosis, attributed to its pivotal roles across diverse physiological and pathological conditions including developmental processes, metabolic dynamics, oncogenic pathways, neurodegenerative cascades, and traumatic tissue injuries. By unraveling the intricate underpinnings of the molecular machinery, pivotal contributors, intricate signaling conduits, and regulatory networks governing ferroptosis, researchers aim to bridge the gap between the intricacies of this unique mode of cellular death and its multifaceted implications for health and disease. In light of the rapidly advancing landscape of ferroptosis research, we present a comprehensive review aiming at the extensive implications of ferroptosis in the origins and progress of human diseases. This review concludes with a careful analysis of potential treatment approaches carefully designed to either inhibit or promote ferroptosis. Additionally, we have succinctly summarized the potential therapeutic targets and compounds that hold promise in targeting ferroptosis within various diseases. This pivotal facet underscores the burgeoning possibilities for manipulating ferroptosis as a therapeutic strategy. In summary, this review enriched the insights of both investigators and practitioners, while fostering an elevated comprehension of ferroptosis and its latent translational utilities. By revealing the basic processes and investigating treatment possibilities, this review provides a crucial resource for scientists and medical practitioners, aiding in a deep understanding of ferroptosis and its effects in various disease situations.

Ferroptosis: a new strategy for cardiovascular disease

Cardiovascular disease (CVD) is currently one of the prevalent causes of human death. Iron is one of the essential trace elements in the human body and a vital component of living tissues. All organ systems require iron for various metabolic processes, including myocardial and skeletal muscle metabolism, erythropoiesis, mitochondrial function, and oxygen transport. Its deficiency or excess in the human body remains one of the nutritional problems worldwide. The total amount of iron in a normal human body is about 3-5 g. Iron deficiency may cause symptoms such as general fatigue, pica, and nerve deafness, while excessive iron plays a crucial role in the pathophysiological processes of the heart through ferroptosis triggered by the Fenton reaction. It differs from other cell death modes based on its dependence on the accumulation of lipid peroxides and REDOX imbalance, opening a new pathway underlying the pathogenesis and mechanism of CVDs. In this review, we describe the latest research progress on the mechanism of ferroptosis and report its crucial role and association with miRNA in various CVDs. Finally, we summarise the potential therapeutic value of ferroptosis-related drugs or ferroptosis inhibitors in CVDs.

Canagliflozin Ameliorates Ventricular Remodeling through Apelin/Angiotensin-Converting Enzyme 2 Signaling in Heart Failure with Preserved Ejection Fraction Rats

INTRODUCTION

The aim of this study was to investigate the effect of canagliflozin (CANA) on ventricular remodeling in patients with preserved ejection fraction (HFpEF) heart failure and to further investigate its possible molecular mechanisms.

METHODS

A high-salt diet was used to induce the formation of HFpEF model in salt-sensitive rats. The rats were fed with CANA and irbesartan, respectively. The mice were divided into control group, model group, CANA group, irbesartan group, and combined drug group. After 12 weeks of feeding, the rats were evaluated by measuring the relevant indexes and echocardiography for cardiac function. Histological analysis was performed using Masson trichrome staining and immunohistochemical staining. RT-qPCR and Western blot were used to quantify the relevant genes and proteins.

RESULTS

In this study, CANA exhibited diuresis, decreased blood pressure, weight loss, and increased food and water intake. Following a high-salt diet, Dahl salt-sensitive rats developed hypertension followed by left ventricular diastolic dysfunction, myocardial fibrosis, and left ventricular remodeling. Myocardial hypertrophy and fibrosis were reduced, and left ventricular diastolic function and ventricular remodeling improved after CANA treatment. The combination of CANA and irbesartan was superior to monotherapy in reducing blood pressure and improving cardiac insufficiency and left ventricular diastolic dysfunction in rats. CANA improves myocardial fibrosis, left ventricular diastolic dysfunction, and ventricular remodeling by upregulating apelin, activating angiotensin-converting enzyme 2 (ACE2), and increasing ACE2/Ang (1-7)/MASR axis levels.

CONCLUSION

CANA improves myocardial fibrosis, left ventricular diastolic dysfunction, and ventricular remodeling in HFpEF rats through upregulation of apelin/ACE2 signaling.

Zooming in and out of ferroptosis in human disease

Ferroptosis is defined as an iron-dependent regulated form of cell death driven by lipid peroxidation. In the past decade, it has been implicated in the pathogenesis of various diseases that together involve almost every organ of the body, including various cancers, neurodegenerative diseases, cardiovascular diseases, lung diseases, liver diseases, kidney diseases, endocrine metabolic diseases, iron-overload-related diseases, orthopedic diseases and autoimmune diseases. Understanding the underlying molecular mechanisms of ferroptosis and its regulatory pathways could provide additional strategies for the management of these disease conditions. Indeed, there are an expanding number of studies suggesting that ferroptosis serves as a bona-fide target for the prevention and treatment of these diseases in relevant pre-clinical models. In this review, we summarize the progress in the research into ferroptosis and its regulatory mechanisms in human disease, while providing evidence in support of ferroptosis as a target for the treatment of these diseases. We also discuss our perspectives on the future directions in the targeting of ferroptosis in human disease.

Canagliflozin protects diabetic cardiomyopathy by mitigating fibrosis and preserving the myocardial integrity with improved mitochondrial function

Sodium-glucose transport protein 2 (SGLT-2) inhibitors are approved antidiabetic drugs with a beneficial effect on reducing major adverse cardiac events and heart failure hospitalization. Among them, canagliflozin has the least selectivity toward SGLT-2 over the SGLT-1 isoform. Canagliflozin can inhibit SGLT-1 at therapeutic levels; however, the underlying molecular mechanism is not understood. This study aimed to evaluate the effect of canagliflozin on SGLT1 expression in an animal model of diabetic cardiomyopathy (DCM) and its associated effects. In vivo studies were carried out in the most clinically relevant high-fat diet and streptozotocin-induced type-2 diabetes model of diabetic cardiomyopathy, and in vitro studies were performed using cultured rat cardiomyocytes stimulated with high glucose and palmitic acid. DCM was induced in male Wistar rats for 8 weeks with or without 10 mg/kg canagliflozin treatment. At the end of the study, systemic and molecular characteristics were measured using immunofluorescence, quantitative RT‒PCR, immunoblotting, histology, and FACS analysis. SGLT-1 expression was upregulated in DCM hearts and was associated with fibrosis, apoptosis, and hypertrophy. Canagliflozin treatment attenuated these changes. The histological evaluation showed improved myocardial structure, and in vitro results revealed improved mitochondrial quality and biogenesis after canagliflozin treatment. In conclusion, canagliflozin protects the DCM heart by inhibiting myocardial SGLT-1 and associated hypertrophy, fibrosis, and apoptosis. Thus, developing novel pharmacological inhibitors targeting SGLT-1 could be a better strategy for treating DCM and associated cardiovascular complications.

Inhibition of TLR4 Alleviates Heat Stroke-Induced Cardiomyocyte Injury by Down-Regulating Inflammation and Ferroptosis

Inflammatory response and cell death play key roles in the mechanism of myocardial cell injury induced by heat stroke (HS) in rats. Ferroptosis is a newly discovered regulatory type of cell death, which is involved in the occurrence and development of various cardiovascular diseases. However, the role of ferroptosis in the mechanism of cardiomyocyte injury caused by HS remains to be clarified. The purpose of this study was to investigate the role and potential mechanism of Toll-like receptor 4 (TLR4) in cardiomyocyte inflammation and ferroptosis under HS conditions at the cellular level. The HS cell model was established by exposing H9C2 cells at 43 °C for 2 h and then recovering at 37 °C for 3 h. The association between HS and ferroptosis was investigated by adding the ferroptosis inhibitor, liproxstatin-1, and the ferroptosis inducer, erastin. The results show that the expressions of ferroptosis-related proteins recombinant solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) were decreased, the contents of glutathione (GSH) were decreased, and the contents of malondialdehyde (MDA), reactive oxygen species (ROS), and Fe₂₊ were increased in H9C2 cells in the HS group. Moreover, the mitochondria of the HS group became smaller and the membrane density increased. These changes were consistent with the effects of erastin on H9C2 cells and were reversed with liproxstatin-1. The addition of TLR4 inhibitor TAK-242 or NF-κB inhibitor PDTC reduced the expressions of NF-κB and p53, increased the expressions of SLC7A11 and GPX4, reduced the contents of TNF-α, IL-6 and IL-1β, increased the content of GSH and reduced MDA, ROS, and Fe₂₊ levels in H9C2 cells under the HS condition. TAK-242 may improve the mitochondrial shrinkage and membrane density of H9C2 cells induced by HS. In conclusion, this study illustrated that inhibition of the TLR4/NF-κB signaling pathway can regulate the inflammatory response and ferroptosis induced by HS, which provides new information and a theoretical basis for the basic research and clinical treatment of cardiovascular injuries caused by HS.

Iron Metabolism in Cardiovascular Disease: Physiology, Mechanisms, and Therapeutic Targets

The cardiovascular system requires iron to maintain its high energy demands and metabolic activity. Iron plays a critical role in oxygen transport and storage, mitochondrial function, and enzyme activity. However, excess iron is also cardiotoxic due to its ability to catalyze the formation of reactive oxygen species and promote oxidative damage. While mammalian cells have several redundant iron import mechanisms, they are equipped with a single iron-exporting protein, which makes the cardiovascular system particularly sensitive to iron overload. As a result, iron levels are tightly regulated at many levels to maintain homeostasis. Iron dysregulation ranges from iron deficiency to iron overload and is seen in many types of cardiovascular disease, including heart failure, myocardial infarction, anthracycline-induced cardiotoxicity, and Friedreich's ataxia. Recently, the use of intravenous iron therapy has been advocated in patients with heart failure and certain criteria for iron deficiency. Here, we provide an overview of systemic and cellular iron homeostasis in the context of cardiovascular physiology, iron deficiency, and iron overload in cardiovascular disease, current therapeutic strategies, and future perspectives.

Canagliflozin Regulates Ferroptosis, Potentially via Activating AMPK/PGC-1α/Nrf2 Signaling in HFpEF Rats

Aims: Sodium-glucose cotransporter-2 (SGLT2) inhibitors have been found to ameliorate major adverse cardiovascular events in patients with heart failure with preserved ejection fraction (HFpEF), but the exact mechanism is unknown. Ferroptosis is a form of programmed necrosis. Herein, we verified that canagliflozin (CANA) ameliorates heart function in HFpEF rats, partly by regulating ferroptosis, which may be activated by AMPK/PGC-1α/Nrf2 signaling.

Methods: An HFpEF model was established and subjected to CANA treatment. Blood pressure was monitored, and echocardiography was performed at the 12th week. Pathological examination was performed, and expression of ferroptosis-associated proteins and AMPK/PGC-1α/Nrf2 signaling related proteins was detected.

Results: CANA had an antihypertensive effect and increased E/A ratios in HFpEF rats. Myocardial pathology was ameliorated, on the basis of decreased cross-sectional area and intercellular fibrosis. Acyl-CoA synthetase long-chain family member 4 (ACSL4) expression increased, whereas ferritin heavy chain 1 (FTH1) expression decreased in HFpEF rats, which showed iron overload. CANA reversed changes in ACSL4 and FTH1, and decreased iron accumulation, but did not alter glutathione peroxidase 4 (GPX4) expression. The expression of AMPK/PGC-1α/Nrf2 signaling related proteins and heme oxygenase 1 (HO-1) in the HFpEF group decreased but was reverted after CANA treatment.

Conclusions: CANA regulates ferroptosis, potentially via activating AMPK/PGC-1α/Nrf2 signaling in HFpEF rats.

Vascular calcification in chronic kidney disease: contribution of ferroptosis?

Vascular calcification associated with chronic kidney disease (CKD) is an active, regulated process. Apoptosis of vascular smooth muscle cells has long been known to play a major role in its pathogenesis, with apoptotic bodies derived from these cells acting as nucleating structures for calcium crystal formation and deposition. Ye et al. now show in experimental models in vitro and in vivo that ferroptosis can also contribute to the development of vascular calcification in CKD.

Ferroptosis in heart failure

With its complicated pathobiology and pathophysiology, heart failure (HF) remains an increasingly prevalent epidemic that threatens global human health. Ferroptosis is a form of regulated cell death characterized by the iron-dependent lethal accumulation of lipid peroxides in the membrane system and is different from other types of cell death such as apoptosis and necrosis. Mounting evidence supports the claim that ferroptosis is mainly regulated by several biological pathways including iron handling, redox homeostasis, and lipid metabolism. Recently, ferroptosis has been identified to play an important role in HF induced by different stimuli such as myocardial infarction, myocardial ischemia reperfusion, chemotherapy, and others. Thus, it is of great significance to deeply explore the role of ferroptosis in HF, which might be a prerequisite to precise drug targets and novel therapeutic strategies based on ferroptosis-related medicine. Here, we review current knowledge on the link between ferroptosis and HF, followed by critical perspectives on the development and progression of ferroptotic signals and cardiac remodeling in HF.

Ferroptosis: The Potential Target in Heart Failure with Preserved Ejection Fraction

Ferroptosis is a recently identified cell death characterized by an excessive accumulation of iron-dependent reactive oxygen species (ROS) and lipid peroxides. Intracellular iron overload can not only cause damage to macrophages, endothelial cells, and cardiomyocytes through responses such as lipid peroxidation, oxidative stress, and inflammation, but can also affect cardiomyocyte Ca²⁺ handling, impair excitation–contraction coupling, and play an important role in the pathological process of heart failure with preserved ejection fraction (HFpEF). However, the mechanisms through which ferroptosis initiates the development and progression of HFpEF have not been established. This review explains the possible correlations between HFpEF and ferroptosis and provides a reliable theoretical basis for future studies on its mechanism.

Canagliflozin mitigates ferroptosis and improves myocardial oxidative stress in mice with diabetic cardiomyopathy

Canagliflozin (Cana), an anti-diabetes drug belongs to sodium-glucose cotransporter 2 inhibitor, is gaining interest because of its extra cardiovascular benefits. Ferroptosis is a new mode of cell death, which can promote the occurrence of diabetic cardiomyopathy (DCM). Whether Cana can alleviate DCM by inhibiting ferroptosis is the focus of this study. Here, we induced DCM models in diabetic C57BL6 mice and treated with Cana. Meanwhile, in order to exclude its hypoglycemic effect, the high glucose model in H9C2 cells were established. In the in vivo study, we observed that Cana could effectively alleviate the damage of cardiac function in DCM mice, including the increasing of lactate dehydrogenase (LDH) and cardiac troponin I (cTnI), the alleviating of myocardial fiber breakage, inflammation, collagen fiber deposition and mitochondrial structural disorder. We evaluated reactive oxygen species (ROS) levels by DCFH-DA and BODIPY 581/591 C11, in vitro Cana reduced ROS and lipid ROS in H9C2 cells induced by high glucose. Meanwhile, JC-1 fluorochrome assay showed that the decreased mitochondrial membrane potential (MMP) was increased by Cana. Furthermore, the inhibitory effects of Cana on myocardial oxidative stress and ferroptosis were verified in vivo and in vitro by protein carbonyl (PCO), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH). As a key inducer of ferroptosis, the deposition of total iron and Fe²⁺ can be inhibited by Cana both in vivo and in vitro. In addition, western blot results indicated that the expression of ferritin heavy-chain (FTN-H) was down-regulated, and cystine-glutamate antiporter (xCT) was up-regulated by Cana in DCM mice and cells, suggesting that Cana inhibit ferroptosis by balancing cardiac iron homeostasis and promoting the system Xc^-/GSH/GPX4 axis in DCM. These findings underscore the fact that ferroptosis plays an important role in the development and progression of DCM and targeting ferroptosis may be a novel strategy for prevention and treatment. In conclusion, Cana may exert some of its cardiovascular benefits by attenuating ferroptosis.