Programmed Cell Death: Complex Regulatory Networks in Cardiovascular Disease

Circular RNAs modulate cell death in cardiovascular diseases

Cardiovascular diseases (CVDs) remain a global health challenge, with programmed cell death (PCD) mechanisms like apoptosis and necroptosis playing key roles in the progression. Circular RNAs (circRNAs) have recently been recognized as crucial regulators of gene expression, especially in modulating PCD. In current researches, circRNA regulation of apoptosis is the most studied area, followed by autophagy and ferroptosis. Notably, the regulatory role of circRNAs in pyroptosis and necroptosis has also begun to attract attention. From a mechanistic perspective, circRNAs influence cellular processes through several modes of action, including miRNA sponging, protein interactions, and polypeptide translation. Manipulating circRNAs and their downstream targets through inhibition or overexpression offers versatile therapeutic options for CVD treatment. Continued investigation into circRNA-mediated mechanisms may enhance our understanding of CVD pathophysiology and underscore their potential as novel and promising therapeutic targets.

New insights into pulmonary arterial hypertension: interaction between PANoptosis and perivascular inflammatory responses

Pulmonary arterial hypertension (PAH) is a heterogeneous disease characterized by various etiologies, with pulmonary vascular remodeling recognized as a main pathological change. Currently, it is widely accepted that vascular remodeling is closely associated with abnormal pulmonary vascular cell death and perivascular inflammation. The simultaneous activation of various pulmonary vascular cell death leads to immune cell adhesion and inflammatory mediator releases; And in turn, the inflammatory response may also trigger cell death and jointly promote the progression of vascular remodeling. Recently, PANoptosis has been identified as a phenomenon that describes the simultaneous activation and interaction of multiple forms of programmed cell death (PCD). Therefore, the relationship between PANoptosis and inflammation in PAH warrants further investigation. This review examines the mechanisms underlying apoptosis, necroptosis, pyroptosis, and inflammatory responses in PAH, with a focus on PANoptosis and its interactions with inflammation. And it aims to elucidate the significance of this emerging form of cell death and inflammation in the pathophysiology of PAH and to explore its potential as a therapeutic target.

Carvedilol Confers Ferroptosis Resistance in HL-1 Cells by Upregulating GPX4, FTH1, and FTL1 and Inducing Metabolic Remodeling Under Hypoxia/Reoxygenation

Hypoxia/reoxygenation (HR) often occurs under cardiac pathological conditions, and HR-induced oxidative stress usually leads to cardiomyocyte damage. Carvedilol, a non-selective β-blocker, is used clinically to treat cardiac ischemia diseases. Moreover, Carvedilol has also been reported to have an antioxidant ability by reducing lipid peroxidation. However, the mechanism of Carvedilol to inhibit lipid peroxidation is still elusive. To explore the protective mechanism of Carvedilol to resist lipid peroxidation on cardiomyocytes, HL-1 cells were cultured under normoxia, hypoxia, and HR and treated with Carvedilol to investigate the alteration on metabolism, protein expression, and mRNA level to explain its oxidative mechanism. The study found that Carvedilol upregulated glutathione peroxidase 4 (GPX4) protein expression to resist HR-induced lipid peroxidation by metabolic remodeling under HR. Also, Carvedilol promoted ferroptosis-related genes, ferritin heavy chain 1 (FTH1) and ferritin light chain 1 (FTL1) mRNA levels, to reduce lipid peroxidation under both hypoxia and HR. In conclusion, our study explores a mechanism by which Carvedilol inhibits ferroptosis by upregulating GPX4, FTH1, and FTL1 levels to downregulate lipid peroxidation under HR. The study provides a potential strategy for using Carvedilol in clinical applications, inspiring further research and development in the area of heart diseases.

Serum Level of RIPK1/3 Correlated With the Prognosis in ICU Patients With Acute Ischemic Stroke

BACKGROUND

Acute ischemic stroke (AIS) is a common cerebrovascular disease with high mortality. AIS patients in the intensive care unit (ICU) often have severe conditions that require close monitoring and timely treatment. Receptor-interacting protein kinase 1 (RIPK1) and RIPK3 play important roles in cell apoptosis and inflammation. However, the relevance of serum RIPK1/3 to AIS patients in the ICU has not been clarified.

OBJECTIVE

To explore the correlation of serum RIPK1 and RIPK3 with the prognosis of AIS patients in the ICU.

METHODS

One hundred and twenty AIS patients were selected as the research subjects for the retrospective analysis. The subjects were grouped based on the volume of cerebral infarction and the score of the National Institute of Health Stroke Scale (NIHSS) and mRS. The correlation was explored using Pearson analysis. The predictive value was valued using the ROC curve.

RESULTS

The content of serum RIPK1 and RIPK3 was gradually elevated with increased cerebral infarction volume and the severity of the disease (p < 0.05). Patients with poor prognosis had a higher content of serum RIPK1 and RIPK3 than those with good prognosis (p < 0.05). Serum RIPK1 and RIPK3 levels were positively correlated with infarct volume, NHISS, and mRS scores (p < 0.001). The area under the curve (AUC) of RIPK1 and RIPK3 for predicting the severity of AIS was 0.703, 0.883, and 0.912, respectively. The AUC for predicting poor prognosis of AIS was 0.797, 0.721, and 0.893, respectively. The cooperative detection of RIPK1 and RIPK3 had higher clinical value.

CONCLUSION

AIS patients in the ICU had abnormally elevated content of serum RIPK1 and RIPK3, which was closely related to the volume of cerebral infarction, severity, and prognosis. Combined detection of RIPK1 and RIPK3 might help to early identify the severity and evaluate the prognosis, providing a reference basis for clinical doctors to develop treatment strategies.

M6A modification in cardiovascular disease: With a focus on programmed cell death

N6-methyladenosine (m6A) methylation is one of the most predominant internal RNA modifications in eukaryotes and has become a hot spot in the field of epigenetics in recent years. Cardiovascular diseases (CVDs) are a leading cause of death globally. Emerging evidence demonstrates that RNA modifications, such as the m6A modification, are associated with the development and progression of many diseases, including CVDs. An increasing body of studies has indicated that programmed cell death (PCD) plays a vital role in CVDs. However, the molecular mechanisms underlying m6A modification and PCD in CVDs remain poorly understood. Herein, elaborating on the highly complex connections between the m6A mechanisms and different PCD signaling pathways and clarifying the exact molecular mechanism of m6A modification mediating PCD have significant meaning in developing new strategies for the prevention and therapy of CVDs. There is great potential for clinical application.

WWP2 protects against sepsis-induced cardiac injury through inhibiting cardiomyocyte ferroptosis

Background and Objectives

Cardiac injury plays a critical role in contributing to the mortality associated with sepsis, a condition marked by various forms of programmed cell deaths. Previous studies hinted at the WW domain-containing E3 ubiquitin protein ligase 2 (WWP2) involving in heart failure and endothelial injury. However, the precise implications of WWP2 in sepsis-induced cardiac injury, along with the underlying mechanisms, remain enigmatic.

Methods

Sepsis induced cardiac injury were constructed by intraperitoneal injection of lipopolysaccharide. To discover the function of WWP2 during this process, we designed and performed loss/gain-of-function studies with cardiac-specific vectors and WWP2 knockout mice. Combination experiments were performed to investigate the relationship between WWP2 and downstream signaling in septic myocardium injury.

Results

The protein level of WWP2 was downregulated in cardiomyocytes during sepsis. Cardiac-specific overexpression of WWP2 protected heart from sepsis induced mitochondrial oxidative stress, programmed cell death and cardiac injury, while knockdown or knockout of WWP2 exacerbated this process. The protective potency of WWP2 was predominantly linked to its ability to suppress cardiomyocyte ferroptosis rather than apoptosis. Mechanistically, our study revealed a direct interaction between WWP2 and acyl-CoA synthetase long-chain family member 4 (FACL4), through which WWP2 facilitated the ubiquitin-dependent degradation of FACL4. Notably, we observed a notable reduction in ferroptosis and cardiac injury within WWP2 knockout mice after FACL4 knockdown during sepsis.

Conclusions

WWP2 assumes a critical role in safeguarding the heart against injury induced by sepsis via regulating FACL4 to inhibit LPS-induced cardiomyocytes ferroptosis.

Targeting the programmed cell death (PCD) signaling mechanism with natural substances for the treatment of diabetic cardiomyopathy (DCM)

Diabetic cardiomyopathy (DCM) is one of the severe complications of diabetes, characterized by structural and functional abnormalities in the hearts of diabetic patients without hypertension, coronary heart disease, or valvular heart disease. DCM can progress to heart failure, which is a significant cause of death in diabetic patients, but currently, there is no effective treatment available. Programmed cell death (PCD) is a genetically regulated form of cell death that includes apoptosis, autophagy, necroptosis, ferroptosis, and pyroptosis. PCD is essential for tissue homeostasis and normal development of the body. DCM is a complex condition, and abnormalities in the cascade of PCD signaling have been observed in its pathological process, suggesting that targeting PCD could be a potential therapeutic strategy. Studies have shown that natural substances can effectively modulate PCD to intervene in the treatment of DCM, and their use is safe. This review explores the role of different forms of PCD in the pathogenesis of DCM and summarizes the research progress in targeting PCD with natural substances to treat DCM. It can serve as a basis for further research and drug development to provide new treatment strategies for DCM patients.

Recent Advances in the Mechanisms of Cell Death and Dysfunction in Doxorubicin Cardiotoxicity

Despite recent advances in cancer therapy, anthracycline-based combination therapy remains the standardized first-line strategy and has been found to have effective antitumor actions. Anthracyclines are extremely cardiotoxic, which limits the use of these powerful chemotherapeutic agents. Although numerous studies have been conducted on the cardiotoxicity of anthracyclines, the precise mechanisms by which doxorubicin causes cardiomyocyte death and myocardial dysfunction remain incompletely understood. This review highlights recent updates in mechanisms and therapies involved in doxorubicin-induced cardiomyocyte death, including autophagy, ferroptosis, necroptosis, pyroptosis, and apoptosis, as well as mechanisms of cardiovascular dysfunction resulting in myocardial atrophy, defects in calcium handling, thrombosis, and cell senescence. We sought to uncover potential therapeutic approaches to manage anthracycline cardiotoxicity via manipulation of crucial targets involved in doxorubicin-induced cardiomyocyte death and dysfunction.

Role of pyroptosis in the pathogenesis and treatment of diseases

Programmed cell death (PCD) is regarded as a pathological form of cell death with an intracellular program mediated, which plays a pivotal role in maintaining homeostasis and embryonic development. Pyroptosis is a new paradigm of PCD, which has received increasing attention due to its close association with immunity and disease. Pyroptosis is a form of inflammatory cell death mediated by gasdermin that promotes the release of proinflammatory cytokines and contents induced by inflammasome activation. Recently, increasing evidence in studies shows that pyroptosis has a crucial role in inflammatory conditions like cardiovascular diseases (CVDs), cancer, neurological diseases (NDs), and metabolic diseases (MDs), suggesting that targeting cell death is a potential intervention for the treatment of these inflammatory diseases. Based on this, the review aims to identify the molecular mechanisms and signaling pathways related to pyroptosis activation and summarizes the current insights into the complicated relationship between pyroptosis and multiple human inflammatory diseases (CVDs, cancer, NDs, and MDs). We also discuss a promising novel strategy and method for treating these inflammatory diseases by targeting pyroptosis and focus on the pyroptosis pathway application in clinics.

Physiological ischemic training improves cardiac function through the attenuation of cardiomyocyte apoptosis and the activation of the vagus nerve in chronic heart failure

Purpose

This study investigated the functional outcomes of patients with chronic heart failure (CHF) after physiological ischemic training (PIT), identified the optimal PIT protocol, evaluated its cardioprotective effects and explored the underlying neural mechanisms.

Methods

Patients with CHF were randomly divided into experimental group (n = 25, PIT intervention + regular treatment) and control group (n = 25, regular treatment). The outcomes included the left ventricular ejection fraction (LVEF), brain natriuretic peptide (BNP) and cardiopulmonary parameters. LVEF and cardiac biomarkers in CHF rats after various PIT treatments (different in intensity, frequency, and course of treatment) were measured to identify the optimal PIT protocol. The effect of PIT on cardiomyocyte programmed cell death was investigated by western blot, flow cytometry and fluorescent staining. The neural mechanism involved in PIT-induced cardioprotective effect was assessed by stimulation of the vagus nerve and muscarinic M2 receptor in CHF rats.

Results

LVEF and VO2max increased while BNP decreased in patients subjected to PIT. The optimal PIT protocol in CHF rats was composed of five cycles of 5 min ischemia followed by 5 min reperfusion on remote limbs for 8 weeks. LVEF and cardiac biomarker levels were significantly improved, and cardiomyocyte apoptosis was inhibited. However, these cardioprotective effects disappeared after subjecting CHF rats to vagotomy or muscarinic M2 receptor inhibition.

Conclusion

PIT improved functional outcomes in CHF patients. The optimal PIT protocol required appropriate intensity, reasonable frequency, and adequate treatment course. Under these conditions, improvement of cardiac function in CHF was confirmed through cardiomyocyte apoptosis reduction and vagus nerve activation.

Idebenone attenuates ferroptosis by inhibiting excessive autophagy via the ROS-AMPK-mTOR pathway to preserve cardiac function after myocardial infarction

Cardiovascular diseases (CVDs) are the leading causes of mortality worldwide. As a type of CVDs, myocardial infarction (MI) induces ischemia hypoxia, which leads to excessive reactive oxygen species (ROS), resulting in multiple cell deaths and contributing to the subsequent development of heart failure or premature death. Recent evidence indicates that ROS-induced lipid peroxidation promotes autophagy and ferroptosis, leading to the loss of healthy myocardium and resulting in the dysfunction of cardiac tissue. Theoretically, cardiac function would be preserved after MI by inhibiting autophagy and ferroptosis. As an analog of coenzyme Q10 (CoQ10) and a clinically approved drug, idebenone would be used to inhibit ferroptosis and preserve cardiac function due to its capacity to improve mitochondrial physiology with antioxidant and anti-inflammatory properties. Here, we confirmed that the addition of idebenone inhibited H₂O₂-induced and RSL3-induced ferroptosis. Furthermore, the ROS-AMPK-mTOR pathway axis was identified as the signaling pathway that idebenone stimulated to prevent excessive autophagy and consequent ferroptosis. In the MI animal model, idebenone demonstrated a cardioprotective role by regulating ROS-dependent autophagy and inhibiting ferroptosis, which paves the way for the future clinical translation of idebenone in MI management.

CircSHOC2 Knockdown Alleviates High Glucose-Induced Vascular Endothelial Cell Pyroptosis via Targeting miR-145/FOXO1 Axis In Vitro Condition

Emerging evidence indicates that pyroptosis participates in the pathogenic process of vascular endothelial cells in cardiovascular system complications of diabetes. The roles of circular RNAs (circRNAs) in high glucose (HG)-induced vascular endothelial cells are still unclear. Here, our research investigated the function and mechanism of circRNA circSHOC2 in pyroptosis of vascular endothelial cells. Results indicated that circSHOC2 was up-regulated in HG-induced human umbilical vein endothelial cells (HUVECs). Functionally, cellular assays indicated that circSHOC2 silencing repressed HG-induced HUVECs pyroptosis. Moreover, circSHOC2 targeted miR-145 through miRNA sponge, and FOXO1 functioned as downstream target of miR-145. In conclusion, these findings suggested the potential roles of circSHOC2 on HG-induced vascular endothelial cells in vitro condition, providing new insights for cardiovascular system complications of diabetes.

Bioluminescent RIPoptosome Assay for FADD/RIPK1 Interaction Based on Split Luciferase Assay in a Human Neuroblastoma Cell Line SH-SY5Y

Different programed cell death (PCD) modalities involve protein-protein interactions in large complexes. Tumor necrosis factor α (TNFα) stimulated assembly of receptor-interacting protein kinase 1 (RIPK1)/Fas-associated death domain (FADD) interaction forms Ripoptosome complex that may cause either apoptosis or necroptosis. The present study addresses the interaction of RIPK1 and FADD in TNFα signaling by fusion of C-terminal (CLuc) and N-terminal (NLuc) luciferase fragments to RIPK1-CLuc (R1C) or FADD-NLuc (FN) in a caspase 8 negative neuroblastic SH-SY5Y cell line, respectively. In addition, based on our findings, an RIPK1 mutant (R1C K612R) had less interaction with FN, resulting in increasing cell viability. Moreover, presence of a caspase inhibitor (zVAD.fmk) increases luciferase activity compared to Smac mimetic BV6 (B), TNFα -induced (T) and non-induced cell. Furthermore, etoposide decreased luciferase activity, but dexamethasone was not effective in SH-SY5Y. This reporter assay might be used to evaluate basic aspects of this interaction as well as for screening of necroptosis and apoptosis targeting drugs with potential therapeutic application.

Vagus nerve stimulation exerts cardioprotection against doxorubicin-induced cardiotoxicity through inhibition of programmed cell death pathways

The aberration of programmed cell death including cell death associated with autophagy/mitophagy, apoptosis, necroptosis, pyroptosis, and ferroptosis can be observed in the development and progression of doxorubicin-induced cardiotoxicity (DIC). Vagus nerve stimulation (VNS) has been shown to exert cardioprotection against cardiomyocyte death through the release of the neurotransmitter acetylcholine (ACh) under a variety of pathological conditions. However, the roles of VNS and its underlying mechanisms against DIC have never been investigated. Forty adults male Wistar rats were divided into 5 experimental groups: (i) control without VNS (CSham) group, (ii) doxorubicin (3 mg/kg/day, i.p.) without VNS (DSham) group, (iii) doxorubicin + VNS (DVNS) group, (iv) doxorubicin + VNS + mAChR antagonist (atropine; 1 mg/kg/day, ip, DVNS + Atro) group, and (v) doxorubicin + VNS + nAChR antagonist (mecamylamine; 7.5 mg/kg/day, ip, DVNS + Mec) group. Our results showed that doxorubicin insult led to left ventricular (LV) dysfunction through impaired cardiac autonomic balance, decreased mitochondrial function, imbalanced mitochondrial dynamics, and exacerbated cardiomyocyte death including autophagy/mitophagy, apoptosis, necroptosis, pyroptosis, and ferroptosis. However, VNS treatment improved cardiac mitochondrial and autonomic functions, and suppressed excessive autophagy, apoptosis, necroptosis, pyroptosis, and ferroptosis, leading to improved LV function. Consistent with this, ACh effectively improved cell viability and suppressed cell cytotoxicity in doxorubicin-treated H9c2 cells. In contrast, either inhibitors of muscarinic (mAChR) or nicotinic acetylcholine receptor (nAChR) completely abrogated the favorable effects mediated by VNS and acetylcholine. These findings suggest that VNS exerts cardioprotective effects against doxorubicin-induced cardiomyocyte death via activation of both mAChR and nAChR.

Characterization of glyphosate-induced cardiovascular toxicity and apoptosis in zebrafish

Glyphosate, the most widely used herbicide, presents new hazards to human health. The developmental toxicity of glyphosate, especially its cardiovascular toxicity, needs to be closely monitored. To understand how glyphosate affects development, we performed toxicity tests on zebrafish embryos that were continuously exposed to glyphosate. The results indicated that glyphosate affected the overall development of zebrafish embryos, including mortality, hatching abnormalities, and decreased body length. At the same time, zebrafish embryos exposed to glyphosate exhibited cardiac malformations, including enlarged chambers, thinned ventricular walls, and rhythm disturbances. In addition, defective intersegmental vasculature occurred after glyphosate exposure, indicating impaired angiogenesis. Mechanistically, apoptosis clustered in the heart and vascular regions and levels of ATP and apoptosis-related genes including caspase-3, caspase-9, bax, and bcl-2 were altered. In summary, the data showed that cardiovascular toxicity caused by glyphosate exposure may be related to apoptosis. Our study provides evidence for a link between glyphosate exposure and cardiovascular developmental toxicity. This raises concerns regarding the health risks of the glyphosate.

The crosstalk among autophagy, apoptosis, and pyroptosis in cardiovascular disease

In recent years, the mechanism of cell death has become a hotspot in research on the pathogenesis and treatment of cardiovascular disease (CVD). Different cell death modes, including autophagy, apoptosis, and pyroptosis, are mosaic with each other and collaboratively regulate the process of CVD. This review summarizes the interaction and crosstalk of key pathways or proteins which play a critical role in the entire process of CVD and explores the specific mechanisms. Furthermore, this paper assesses the interrelationships among these three cell deaths and reviews how they regulate the pathogenesis of CVD. By understanding how these three cell death modes go together we can learn about the pathogenesis of CVD, which will enable us to identify new targets for preventing, controlling, and treating CVD. It will not only reduce mortality but also improve the quality of life.

The Role of Polyphenol in Modulating Associated Genes in Diabetes-Induced Vascular Disorders

Diabetes-induced vascular disorder is considered one of the deadly risk factors among diabetic patients that are caused by persistent hyperglycemia that eventually leads to cardiovascular diseases. Elevated reactive oxygen species (ROS) due to high blood glucose levels activate signaling pathways such as AGE/RAGE, PKC, polyol, and hexosamine pathways. The activated signaling pathway triggers oxidative stress, inflammation, and apoptosis which later lead to vascular dysfunction induced by diabetes. Polyphenol is a bioactive compound that can be found abundantly in plants such as vegetables, fruits, whole grains, and nuts. This compound exerts therapeutic effects in alleviating diabetes-induced vascular disorder, mainly due to its potential as an anti-oxidative, anti-inflammatory, and anti-apoptotic agent. In this review, we sought to summarize the recent discovery of polyphenol treatments in modulating associated genes involved in the progression of diabetes-induced vascular disorder.

Suppression of lncRNA Gm47283 attenuates myocardial infarction via miR-706/ Ptgs2/ferroptosis axis

Myocardial infarction (MI) is the leading cause of sudden death. Long non-doing RNAs (lncRNAs) were demonstrated to play crucial roles in multiple diseases, including cancer and cardiovascular diseases. Nevertheless, the molecular mechanism of lncNRAs in MI is unclear. In this study, we integrated bioinformatics and molecular biological experiments to identify the novel lncRNA transcripts and elucidated its regulatory mechanism in MI. First, we identified 10 dysregualted lncRNAs and found that lncRNA Gm47283 was the top risk factor in MI. Bioinformatics analysis predicted that lncRNA Gm47283 exerted function via targeting miR-706 and Ptgs2. Ptgs2 was also the known regulator of ferroptosis. Inhibition or overexpression of lncRNA Gm47283 could regulate Ptgs2 expression and downstream ferroptosis activity. Overexpression of miR-706 could inhibit the expression of Ptgs2 and the activity of ferroptosis, thereby attenuated cellular injury. Mechanically, co-transfection experiments showed that overexpression of miR-706 could reverse the damage effect that was caused by lncRNA Gm47283 overexpression, via inhibiting Ptgs2 and ferroptosis. Additionally, inhibition of lncRNA Gm47283 by stem cell membrane coated siRNA could attenuate MI in vivo. Our study elucidated a novel mechanism containing lncRNA Gm47283/miR-706/Ptgs2/ferroptosis in MI, which provided a potential therapeutic for MI.

Graphical Abstract. Stem cell membrane coated siRNA of lncRNA Gm47283 inhibits cardiomyocyte ferroptosis in myocardial infarction rat. Stem cell membrane-coated siRNA of lncRNA Gm47283 increases miR-706, and then miR-706 suppresses the expression of Ptgs2 to reduce lipid peroxidation toxicity, and then inhibits cardiomyocyte ferroptosis. PUFA: polyunsaturated fatty acid.