Rev-erbs agonist SR9009 alleviates ischemia-reperfusion injury by heightening endogenous cardioprotection at onset of type-2 diabetes in rats: Down-regulating ferritinophagy/ferroptosis signaling

Ferroptosis: mechanism and role in diabetes-related cardiovascular diseases

Cardiovascular diseases represent the principal cause of death and comorbidity among people with diabetes. Ferroptosis, an iron-dependent non-apoptotic regulated cellular death characterized by lipid peroxidation, is involved in the pathogenesis of diabetic cardiovascular diseases. The susceptibility to ferroptosis in diabetic hearts is possibly related to myocardial iron accumulation, abnormal lipid metabolism and excess oxidative stress under hyperglycemia conditions. Accumulating evidence suggests ferroptosis can be the therapeutic target for diabetic cardiovascular diseases. This review summarizes ferroptosis-related mechanisms in the pathogenesis of diabetic cardiovascular diseases and novel therapeutic choices targeting ferroptosis-related pathways. Further study on ferroptosis-mediated cardiac injury can enhance our understanding of the pathophysiology of diabetic cardiovascular diseases and provide more potential therapeutic choices.

Time of day dependent reduction in stroke infarct volume by the Reverb agonist SR9009 in mice

Ischemic stroke leads to disability and death worldwide and evidence suggests that stroke severity is affected by the time dimension of the stroke. Rev-Erbα regulates the core circadian clock through repression of the positive clock element Bmal1. However, it remains unclear if a Rev-Erbα agonist (SR9009) alleviates stroke pathology in mice. We found that stroke reduces the level of Rev-Erbα and elevates neuroinflammation and stroke severity at zeitgeber time (ZT) ZT06. Therefore, we hypothesized that SR9009 treatment may reduce neuroinflammation and stroke severity in a mouse suture occlusion model. At 12 to 14 weeks, C57BL/6 J (Wild Type, n = 5-10 mice/group) mice were randomly assigned to undergo MCAO stroke for 60 min at either zeitgeber time ZT06 (MCAO-ZT06-sleep phase) or ZT18 (MCAO-ZT18-awake phase). Stroked mice were treated with SR9009 (100 mg/kg) or vehicle at 1 h and 24 h after MCAO. After forty-eight hours of stroke, TTC staining, Western blot, and qRT-PCR were performed. We found that SR9009 treatment alleviates neuroinflammation and infarct volume by Rev-Erb remodeling in ZT06 stroke mice but not in ZT18 stroke mice. Additionally, monocytic and neutrophilic NLRP3 as well as brain NLRP3 levels were reduced by SR9009 treatment in ZT06 stroke though no effects were observed at ZT18 stroke. SR9009 also reduced TNFα expression and increased IL-10 expression in blood and brain in ZT06 stroke mice and no differences were observed at ZT18. There were no significant effects of SR9009 on neurological deficit score and sensorimotor function at ZT06 or ZT18 at 48 h. Our study demonstrates that SR9009 treatment reduces stroke volume, circulating immune response, circadian expression, and that the protection was circadian- and treatment time-dependent.

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

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

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.

1-Dehydro-6-Gingerdione Exerts Anticancer Effects on MDA-MB-231 Cells and in the Xenograft Mouse Model by Promoting the Ferroptosis Pathway

Breast cancer (BC) is the most prevalent malignancy among women, with millions of newly diagnosed cases emerging annually. Therefore, identifying novel pharmaceuticals for therapeutic purposes is imperative. Several natural compounds and their products have demonstrated potential in the treatment of cancer. This study examined the effects of the ginger derivative 1-dehydro-6-gingerdione (1-D-6-G) on BC and its mechanisms of action. MTT and colony formation assays were used to check the anticancer effect of 1-D-6-G. Then the anticancer mechanism of 1-D-6-G was predicted using proteomics analysis. The molecular pathway was verified by qRT-PCR and immunobloting analysis. Additionally, the anticancer properties of 1-D-6-G were investigated in vivo using xenograft mice model. Finally, an in silico study was conducted to examine the interaction of 1-D-6-G and pathway-related proteins. MTT and colony formation assay results indicated that 1-D-6-G has potent cytotoxic properties against BC cells. Proteomic analysis revealed that the anticancer mechanism of 1-D-6-G on MDA-MB-231 cells is associated with the ferroptosis signaling pathway. In addition, qRT-PCR and immunoblotting analyses revealed that the cytotoxic effects of 1-D-6-G on MDA-MB-231 cells were associated with ferroptosis signaling induction. Our in vivo results further confirmed the in vitro findings. The administration of 1-D-6-G for 14 days exhibited anticancer properties in xenograft mice by stimulating the ferroptosis pathway without causing damage to essential organs such as the liver and kidneys. Additionally, in silico results confirmed the structural stability of the molecular interaction between 1-D-6-G and ferroptosis target proteins. Our findings indicate that 1-D-6-G has the potential to serve as a novel therapeutic agent for inhibiting BC progression by targeting the ferroptosis pathway.

International consensus guidelines for the definition, detection, and interpretation of autophagy-dependent ferroptosis

Macroautophagy/autophagy is a complex degradation process with a dual role in cell death that is influenced by the cell types that are involved and the stressors they are exposed to. Ferroptosis is an iron-dependent oxidative form of cell death characterized by unrestricted lipid peroxidation in the context of heterogeneous and plastic mechanisms. Recent studies have shed light on the involvement of specific types of autophagy (e.g. ferritinophagy, lipophagy, and clockophagy) in initiating or executing ferroptotic cell death through the selective degradation of anti-injury proteins or organelles. Conversely, other forms of selective autophagy (e.g. reticulophagy and lysophagy) enhance the cellular defense against ferroptotic damage. Dysregulated autophagy-dependent ferroptosis has implications for a diverse range of pathological conditions. This review aims to present an updated definition of autophagy-dependent ferroptosis, discuss influential substrates and receptors, outline experimental methods, and propose guidelines for interpreting the results.Abbreviation: 3-MA:3-methyladenine; 4HNE: 4-hydroxynonenal; ACD: accidentalcell death; ADF: autophagy-dependentferroptosis; ARE: antioxidant response element; BH2:dihydrobiopterin; BH4: tetrahydrobiopterin; BMDMs: bonemarrow-derived macrophages; CMA: chaperone-mediated autophagy; CQ:chloroquine; DAMPs: danger/damage-associated molecular patterns; EMT,epithelial-mesenchymal transition; EPR: electronparamagnetic resonance; ER, endoplasmic reticulum; FRET: Försterresonance energy transfer; GFP: green fluorescent protein;GSH: glutathione;IF: immunofluorescence; IHC: immunohistochemistry; IOP, intraocularpressure; IRI: ischemia-reperfusion injury; LAA: linoleamide alkyne;MDA: malondialdehyde; PGSK: Phen Green™ SK;RCD: regulatedcell death; PUFAs: polyunsaturated fatty acids; RFP: red fluorescentprotein;ROS: reactive oxygen species; TBA: thiobarbituricacid; TBARS: thiobarbituric acid reactive substances; TEM:transmission electron microscopy.

Targeting Rev-Erbα to protect against ischemia-reperfusion-induced acute lung injury in rats

BACKGROUND

The dysregulation of local circadian clock has been implicated in the pathogenesis of a broad spectrum of diseases. However, the pathophysiological role of intrinsic circadian clocks Rev-Erbα in ischemia-reperfusion (IR)-induced acute lung injury (ALI) remains unclear.

METHODS

The IR-ALI model was established by subjecting isolated perfused rat lungs to 40 min of ischemia followed by 60 min of reperfusion. Rats were randomly assigned to one of six groups: control, control + SR9009 (Rev-Erbα agonist, 50 mg/kg), IR, and IR + SR9009 at one of three dosages (12.5, 25, 50 mg/kg). Bronchoalveolar lavage fluids (BALF) and lung tissues were obtained and analyzed. In vitro experiments utilized mouse lung epithelial cells (MLE-12) exposed to hypoxia-reoxygenation (HR) and pretreated with SR9009 (10 µM/L) and Rev-Erbα siRNA.

RESULTS

SR9009 exhibited a dose-dependent reduction in lung edema in IR-ALI. It significantly inhibited the production of TNF-α, IL-6, and CINC-1 in BALF. Moreover, SR9009 treatment restored suppressed IκB-α levels and reduced nuclear NF-κB p65 levels in lung tissues. In addition, a SR9009 mitigated IR-induced apoptosis and mitogen-activated protein kinase (MAPK) activation in injured lung tissue. Finally, treatment with Rev-Erbα antagonist SR8278 abolished the protective action of SR9009. In vitro analyses showed that SR9009 attenuated NF-κB activation and KC/CXCL-1 levels in MLE-12 cells exposed to HR, and these effects were significantly abrogated by Rev-Erbα siRNA.

CONCLUSIONS

The findings suggest that SR9009 exerts protective effects against IR-ALI in a Rev-Erbα-dependent manner. SR9009 may provide a novel adjuvant therapeutic approach for IR-ALI.

Comprehensive analysis of ferritinophagy-related genes and immune infiltration landscape in diabetic retinopathy

Background

Diabetic retinopathy (DR) is deemed a microangiopathy and neurodegenerative disorder, which is a primary reason of visual impairment in the world. Ferritinophagy is a critical regulator of ferroptosis and has a vital part in the etiopathogenesis of DR. Nevertheless, its molecular mechanism in DR remains to be expounded.

Methods

The GSE146615 dataset was adopted to identify ferritinophagy-related differentially expressed genes (FRDEGs). The interactions and biological functions of the genes were described by means of functional enrichment analysis (FEA). The enriched gene sets were analyzed utilizing gene set enrichment analysis (GSEA) and gene set variation analysis (GSVA). Identification of hub genes was performed utilizing protein-protein interaction (PPI) analysis. mRNA-miRNA, mRNA-transcription factors (TF), mRNA-drugs, mRNA-RNA-binding proteins (RBP) interaction networks were constructed. In addition, datasets GSE60436 and GSE94019 were utilized for validation. The diagnostic performance of FRDEGs was assessed by means of receiver-operating characteristic curve monofactor analysis, followed by immune infiltration analysis. Lastly, quantitative real-time polymerase chain reaction (qRT-PCR) was implemented to analyze the validation of genes.

Results

In total, the identification of eight FRDEGs was completed utilizing differential expression analysis. FEA mainly implicated the autophagy of mitochondrion, mitochondrion disassembly, autophagosome assembly, and organization pathways. GSEA and GSVA mainly implicated the interferon alpha response, ultraviolet response up, interferon gamma response, apical junction, pical surface, and allograft rejection pathways. BECN1 and HERC2 displayed high diagnostic accuracies in validation sets. Immune infiltration analysis revealed that several immune cells related to ferritinophagy may be play potential roles in DR. Finally, qRT-PCR was utilized to validate the upregulated expression of BECN1 as well as the downregulated expression of BCAT2 and ATG7 in the DR model.

Conclusion

BECN1, HERC2, ATG7, and BCAT2 act as potential biomarkers for DR and might regulate ferritinophagy and the immune microenvironment to influence its development and progression. This research can provide new insights into pathogenesis of DR related to ferritinophagy.

Circadian Rhythm Regulator REV-ERBα Attenuates Neuroapoptosis in Early Brain Injury After Experimental Subarachnoid Hemorrhage in Rats

Subarachnoid hemorrhage (SAH) is associated with circadian rhythm abnormalities, in which REV-ERBα plays a major regulatory role. Our ambition was to investigate the capacity of REV-ERBα to inhibit neuronal neuroapoptosis induced by early brain injury (EBI) after SAH. The endovascular perforation model was used to produce experimental SAH in Sprague-Dawley rats. Specific small-interfering RNA was used to downregulate the expression REV-ERBα while SR9009 was used to upregulate the expression before assessments. Short- and long-term neurobehavior assessments, immunofluorescence staining, TUNEL staining, Nissl staining, brain water content, and Western blot were performed. The expression level of endogenous REVERBα tended to increase and then decrease after SAH and peaked at 48 h. REV-ERBα upregulation diminished neuronal apoptosis and enhanced neurological function deficits. Meanwhile, REV-ERBα downregulation aggravated the damage. Furthermore, the levels of downstream proteins of REV-ERBα (i.e., brain and muscle ARNT-like 1 (BMAL1) and circadian locomotor output cycles kaput (CLOCK)) changed accordingly with REV-ERBα regulation. REV-ERBα may attenuate neuronal apoptosis in EBI after SAH through the BMAL1/CLOCK pathway.

Targeting ferroptosis as a promising therapeutic strategy to treat cardiomyopathy

Cardiomyopathies are a clinically heterogeneous group of cardiac diseases characterized by heart muscle damage, resulting in myocardium disorders, diminished cardiac function, heart failure, and even sudden cardiac death. The molecular mechanisms underlying the damage to cardiomyocytes remain unclear. Emerging studies have demonstrated that ferroptosis, an iron-dependent non-apoptotic regulated form of cell death characterized by iron dyshomeostasis and lipid peroxidation, contributes to the development of ischemic cardiomyopathy, diabetic cardiomyopathy, doxorubicin-induced cardiomyopathy, and septic cardiomyopathy. Numerous compounds have exerted potential therapeutic effects on cardiomyopathies by inhibiting ferroptosis. In this review, we summarize the core mechanism by which ferroptosis leads to the development of these cardiomyopathies. We emphasize the emerging types of therapeutic compounds that can inhibit ferroptosis and delineate their beneficial effects in treating cardiomyopathies. This review suggests that inhibiting ferroptosis pharmacologically may be a potential therapeutic strategy for cardiomyopathy treatment.

Ferroptosis-A New Dawn in the Treatment of Organ Ischemia-Reperfusion Injury

Ischemia-reperfusion (I/R) is a common pathological phenomenon that occurs in numerous organs and diseases. It generally results from secondary damage caused by the recovery of blood flow and reoxygenation, followed by ischemia of organ tissues, which is often accompanied by severe cellular damage and death. Currently, effective treatments for I/R injury (IRI) are limited. Ferroptosis, a new type of regulated cell death (RCD), is characterized by iron overload and iron-dependent lipid peroxidation. Mounting evidence has indicated a close relationship between ferroptosis and IRI. Ferroptosis plays a significantly detrimental role in the progression of IRI, and targeting ferroptosis may be a promising approach for treatment of IRI. Considering the substantial progress made in the study of ferroptosis in IRI, in this review, we summarize the pathological mechanisms and therapeutic targets of ferroptosis in IRI.