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Berberine is reported to protect the heart against ischemia/reperfusion (I/R) injury, although efficacy is limited by low bioavailability. This study aims to determine whether borneol, a classic guiding drug, can enhance the cardioprotection induced by berberine and to clarify the underlying mechanisms involving P-glycoprotein (P-gp) in the heart. Adult male Sprague Dawley rats were gavaged with berberine (200 mg/kg) with or without borneol (100 mg/kg) for 7 consecutive days. A rat model of myocardial I/R injury was established by 30 min left coronary artery occlusion followed with 120 min reperfusion. The arrhythmia score, cardiac enzyme content, and myocardial infarct size were determined following reperfusion. Heart tissues were collected for Western blot and immunofluorescence analyses to measure the protein expression levels of Bcl-2, Bax, and P-gp. The results showed that administration of berberine protected the heart against I/R injury, as demonstrated by lower arrhythmia scores, serum cTnI contents, myocardial infarct size, and cardiomyocytes apoptosis. Moreover, borneol substantially enhanced the cardioprotective effects of berberine. Western blot and immunofluorescence analyses showed that both berberine and I/R injury did not alter P-gp expression in heart. In contrast, borneol combined with berberine significantly reduced P-gp levels by 43.4% (P = 0.0240). Interestingly, treatment with borneol alone decreased P-gp levels, but did not protect against myocardial I/R injury. These findings suggest that borneol, as an adjuvant drug, improved the cardioprotective effects of berberine by inhibiting P-gp expression in heart. Borneol combined with berberine administration provides a new strategy to protect the heart against I/R injury., Competing Interests: Declaration of competing interest The authors have declared no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Myocardial ischemia/reperfusion (MI/R) injury, a major contributor to poor prognosis in patients with acute myocardial infarction, currently lacks effective therapeutic strategies in clinical practice. The long noncoding RNA (lncRNA) Oip5-as1 can regulate various cellular processes, such as cell proliferation, differentiation, and survival. Oip5-as1 may have potential as a therapeutic target for MI/R injury as its upregulated expression has been associated with reduced infarct size and improved cardiac function in animal models, although how to effectively and safely overexpress Oip5-as1 in vivo remains unclear. Lipid nanoparticles (LNPs) are a versatile technology for targeted drug delivery in numerous therapeutic applications. Herein, we aimed to assess the therapeutic efficacy and safety of LNPs coloaded with Oip5-as1 and a cardiomyocyte-specific binding peptide (LNP@Oip5-as1@CMP) in a murine model of MI/R injury. To achieve this, LNP@Oip5-as1@CMP was synthesized via ethanol injection method. The structural components of LNP@Oip5-as1@CMP were physicochemically analyzed. A hypoxia/reoxygenation (H/R) model in HL-1 cells and coronary artery ligation in mice were used to simulate MI/R injury. Our results demonstrated that LNPs designed for cardiomyocyte targeting and efficient Oip5-as1 delivery were successfully synthesized. In HL-1 cells, LNP@Oip5-as1@CMP treatment significantly reduced mitochondrial apoptosis caused by H/R injury. In the murine MI/R model, the intravenous administration of LNP@Oip5-as1@CMP significantly decreased myocardial infarct size and improved cardiac function. Mechanistic investigations revealed that Oip5-as1 delivery inhibited the p53 signaling pathway. However, the cardioprotective effects of Oip5-as1 were abrogated by administrating Nutlin-3a, a p53 activator. Furthermore, no signs of major organ damage were detected after LNP@Oip5-as1@CMP injection. Our study reveals the therapeutic potential of LNPs for targeted Oip5-as1 delivery in mitigating MI/R injury. These findings pave the way for advanced targeted treatments in cardiovascular diseases, emphasizing the promise of lncRNA-based therapies.

Background: Ischemia-induced cellular damage and stress responses significantly impact cellular viability and function. Icariin (ICA), known for its protective effects, has been studied to understand its role in mitigating oxygen-glucose deprivation/reperfusion (OGD/R)-induced endoplasmic reticulum (ER) stress and ferroptosis in H9C2 cardiomyoblast cells., Methods: We employed an in vitro OGD/R model using H9C2 cells. ICA's effects were analyzed across multiple concentrations. Key indicators of ER stress, autophagy, and ferroptosis-including markers like Bip, PERK, IRE1, ATF6, P62, FTH1, LC3II/LC3I, and NCOA4-were assessed using Western blotting, electron microscopy, and biochemical assays. Additionally, the role of the IRE1/JNK pathway in mitochondrial dynamics and its influence on mitochondrial dynamics protein was explored through specific inhibition and activation experiments., Results: ICA significantly reduced the activation of UPR pathways, decreased autophagic vacuole formation, and maintained cell viability in response to OGD/R and Erastin-induced ferroptosis. These protective effects were associated with modulated autophagic processes, reduced lipid peroxidation, and decreased ferrous ion accumulation. Inhibition of the IRE1/JNK pathway and subsequent Drp1 activity demonstrated reduced mitochondrial recruitment and mitophagy, correlating with decreased ferroptosis markers and improved cell survival., Conclusion: Our findings highlight ICA's potential in modulating IRE1/JNK pathway, autophagy, providing a therapeutic avenue for mitigating ferroptosis in myocardial ischemia-reperfusion injury (MIRI)., Competing Interests: Declaration of competing interest There are no financial or other conflicts of interest that could have affected the outcomes or interpretation of this study., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Cardiac microvascular damage is substantially related with the onset of myocardial ischaemia-reperfusion (IR) injury. Reportedly, allicin (AL) effectively protects the cardiac microvascular system from IR injury. However, the unsatisfactory therapeutic efficacy of current drugs and insufficient drug delivery to the damaged heart are major concerns. Here, inspired by the natural interaction between neutrophils and inflamed cardiac microvascular endothelial cells (CMECs), a neutrophil membrane-camouflaged nanoparticle for non-invasive active-targeting therapy for IR injury by improving drug delivery to the injured heart is constructed., Methods: In this study, we engineered mesoporous silica nanoparticles (MSNs) coated with a neutrophil membrane to act as a drug delivery system, encapsulating AL. The potential of the nanoparticles (named AL@MSNs@NM) for specific targeting of infarcted myocardium was assessed using small animal vivo imaging system. The cardiac function of AL@MSNs@NM after treatment was evaluated by Animal Ultrasound Imaging system, HE staining, and Laser Speckle Imaging System. The therapeutic mechanism was analyzed by ELISA kits, immunofluorescence, and PCR., Results: We discovered that AL@MSNs@NM significantly improves cardiac function index, reduced infarct size and fibrosis, increased vascular perfusion in ischemic areas, and also promoted the function of CMECs, including migration, tube formation, shear stress adaptation, and nitric oxide production. Further research revealed that AL@MSNs@NM have cardio-protective functions in IR rats by inhibiting CMEC ferroptosis and increasing platelet endothelial cell adhesion molecule-1 (PECAM-1) expression., Conclusion: Our results indicated that AL@MSNs@NM significantly reversed CMEC ferroptosis and increased PECAM-1 expression, enhanced cardiac function, and reduced myocardial infarction size. Therefore, this strategy demonstrates that engineered biomimetic nanotechnology effectively delivers AL for targeted therapy of myocardial infarction., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Li et al.)

Background: Acute myocardial ischemia/reperfusion injury (MIRI) with complicated mechanisms contributes to a high risk of ventricular arrhythmia, high lethality, and even sudden death. In vitro, Fraxinellone (FRA) exhibits an array of biologic activities and may possess cardioprotective effects. However, no relevant studies have examined FRA's protective potential against MIRI and related ventricular arrhythmias. The present study was undertaken to determine the effectiveness of FRA on MIRI and ventricular fibrillation (VF) susceptibility in rats and to elucidate the underlying mechanisms., Methods: 48 healthy male Sprague-Dawley (SD) rats were randomly divided into the following four groups: Sham+vehicle(n=12), Sham+FRA(n=12), I/R+vehicle(n=12) and I/R+FRA(n=12). Histopathology, electrophysiological examination, HRV analysis in combination with molecular biology were used to investigate the therapeutic benefits of FRA on cardiac injury and VF susceptibility during myocardial IR. Finally, the potential mechanism by which FRA protects myocardium from MIRI was explored., Results: Pretreatment with FRA ameliorated myocardial fibrosis after MIRI in vivo, alleviated myocardial injury, inflammation, oxidative stress and apoptosis in vivo and in vitro, thereby protecting myocardium from MIRI injury. In addition, FRA administration could improve HRV, prolong ventricular effective refractory period (ERP) and action potential duration (APD), attenuate VF induction rate, and contribute to improving ventricular sympathetic nerve remodeling and ion channel remodeling. Mechanistically, FRA may reduce MIRI via the PI3K/AKT pathway., Conclusion: FRA may exert cardioprotective effects during MIRI by inhibiting myocardial inflammation, oxidative stress and apoptosis, and decrease VF susceptibility by improving sympathetic remodeling and ion channel remodeling, which might represent a potential therapeutic strategy for attenuation of MIRI., Competing Interests: Declaration of Competing Interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Apoptosis is a crucial pathological process in myocardial ischemia/reperfusion injury (MIRI). Verapamil (Ver), normally used to treat hypertension or heart rhythm disorders, also attenuates MIRI. The potential of Ver to inhibit apoptosis and thereby attenuate MIRI remains unclear, as does the mechanism. We established an in vivo mouse ischemia/reperfusion (I/R) model by occlusion of the left anterior descending coronary. To construct a hypoxia/reoxygenation model in vitro, H9c2 cardiomyocytes were immersed in a hypoxic buffer in a hypoxia/anaerobic workstation. Ver significantly improved cardiac function and reduced myocardial infarction size in I/R mice, while decreasing apoptosis. Both in vivo and in vitro, application of Ver activated the JAK2/STAT3 signaling pathway and elevated Bcl-2 expression, while decreasing Bax and cleaved caspase-3 levels. Treatment with AG490, a JAK2 inhibitor, partially counteracted the anti-apoptotic and the cardioprotective effect of Ver. Thus, we conclude that Ver alleviates MIRI by reducing apoptosis via the JAK2/STAT3 signaling pathway activation. These findings provide a novel mechanism of Ver in the treatment of MIRI., Competing Interests: Declaration of Competing Interest The authors of this article declare that they have no known competing financial interests or personal relationships that could possibly influence the work reported in this article., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Tetramethylpyrazine (TMP) belongs to the active ingredients of the traditional Chinese medicine Chuanxiong, which has a certain protective effect in myocardial ischemia-reperfusion (I/R) injury. It can improve postoperative cardiac function and alleviate ventricular remodeling in acute myocardial infarction patients. However, its specific protective mechanism is still unclear. In this study, a certain concentration of TMP was introduced into I/R mice or H9C2 cells after oxygen-glucose deprivation/reoxygenation (OGD/R) treatment to observe the effects of TMP on cardiomyocyte activity, cytotoxicity, apoptosis, autophagy, pyroptosis, and NLRP3 inflammasome activation. The results displayed that TMP intervention could reduce OGD/R and I/R-induced cardiomyocyte apoptosis, accelerate cellular activity and autophagy levels, and ameliorate myocardial tissue necrosis in I/R mice in a dose-dependent manner. Further, TMP prevented the formation of NLRP3 inflammasomes to suppress pyroptosis by increasing the level of cardiomyocyte autophagy after I/R and OGD/R modelling, the introduction of chloroquine to suppress autophagic activity in vivo and in vitro was further analyzed to confirm whether TMP inhibits NLRP3 inflammasome activation and pyroptosis by increasing autophagy, and we found the inhibitory effect of TMP on NLRP3 inflammasomes and its protective effect against myocardial injury were blocked when autophagy was inhibited with chloroquine. In conclusion, this experiment demonstrated that TMP unusually attenuated I/R injury in mice, and this protective effect was achieved by inhibiting the activation of NLRP3 inflammasomes through enhancing autophagic activity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Myocardial ischemia/reperfusion injury (MI/RI) generates reactive oxygen species (ROS) and initiates inflammatory responses. Traditional therapies targeting specific cytokines or ROS often prove inadequate. An innovative drug delivery system (DDS) is developed using neutrophil decoys (NDs) that encapsulate 18β-glycyrrhetinic acid (GA) within a hydrolyzable oxalate polymer (HOP) and neutrophil membrane vesicles (NMVs). These NDs are responsive to hydrogen peroxide (H 2 O 2 ), enabling controlled GA release. Additionally, NDs adsorb inflammatory factors, thereby reducing inflammation. They exhibit enhanced adhesion to inflamed endothelial cells (ECs) and improved penetration. Once internalized by cardiomyocytes through clathrin-mediated endocytosis, NDs protect against ROS-induced damage and inhibit HMGB1 translocation. In vivo studies show that NDs preferentially accumulate in injured myocardium, reducing infarct size, mitigating adverse remodeling, and enhancing cardiac function, all while maintaining favorable biosafety profiles. This neutrophil-based system offers a promising targeted therapy for MI/RI by addressing both inflammation and ROS, holding potential for future clinical applications., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Background: Chinese dragon's blood, the red resin of Dracaena cochinchinensis (Lour.) S. C. Chen., is widely used to treat cardiovascular and cerebrovascular diseases in China. Longxuetongluo Capsule (LTC) is a total phenolic compound extracted from Chinese dragon's blood, currently used in treating ischemic stroke. Myocardial injury can be aggravated after reperfusion of ischemic myocardium, which is called myocardial ischemia-reperfusion injury (MIRI), and the mechanism of MIRI is complex. However, the exact effect and mechanism of LTC on MIRI are still unclear. We explore the effect of LTC on alleviating MIRI based on mitochondrial dysfunction and oxidative stress., Aim of the Study: To explore the cardioprotective mechanism of LTC against MIRI., Materials and Methods: A rat MIRI model was constructed through ligation of the left anterior descending coronary artery, and LTC was given continuously for 28 days before surgery. The H9c2 cardiomyocyte injury model was induced by oxygen-glucose deprivation/reperfusion (OGD/R), and LTC was given 24 h before OGD. Myocardial ischemia areas were detected with 2,3,5-triphenyltetrazolium chloride (TTC) staining. Cardiac histopathological changes were detected with hematoxylin-eosin (HE) staining. And biochemical indexes were detected with serum biochemical kit. Terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) staining and flow cytometry were used to detect apoptosis. Fluorescent probes were used to observe reactive oxygen species (ROS), mitochondrial membrane potential (ΔΨm), Ca 2+ and other indexes. MitoTracker staining and immunofluorescence were used to observe the morphology of mitochondria and translocation of dynamin-related protein 1 (Drp1). Finally, immunohistochemistry and Western blotting were used to examine the expression of proteins related to apoptosis, mitochondrial fission and fusion and oxidative stress., Results: LTC could ameliorate cardiac pathological changes, decrease myocardial infarct area and the content or level of relevant serum cardiac enzymes, indicating that LTC could alleviate MIRI. Meanwhile, LTC could inhibit cardiomyocyte apoptosis via regulating apoptosis-related protein expression, and it could restore mitochondrial morphology, maintain ΔΨm, inhibit mitochondrial ROS generation and Ca 2+ accumulation, increase the expression of mitochondrial fusion protein 2 (Mfn2), decrease the level of phosphorylation dynamin-related protein 1 (p-Drp1), and regulate ATP synthesis, thereby significantly ameliorating mitochondrial dysfunction. Moreover, LTC significantly reduced the expression of NADPH oxidase 2 (NOX2), NADPH oxidase 4 (NOX4) and neutrophil cytosolic factor 2 (NOXA2/p67 phox ), and reduced ROS production., Conclusion: The study demonstrated that LTC could inhibit MIRI induced cardiomyocyte apoptosis by inhibiting ROS generation and mitochondrial dysfunction, and these fundings suggested that LTC can be used to alleviate MIRI, which provides a potential therapeutic approach for future treatment of MIRI., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Reperfusion therapy is the primary treatment strategy for acute myocardial infarction (AMI). Paradoxically, it can lead to myocardial damage, namely myocardial ischemia/reperfusion injury (MIRI). This study explored whether oroxylin A (OA) protects the myocardium after MIRI by inhibiting ferroptosis and the underlying mechanism. In vivo, we established an MIRI model to investigate the protective effect of OA. In vitro, H9C2 cells were used to explore the regulation of ferroptosis by OA through immunofluorescence staining, western blotting, assay kits, etc. Additionally, RNA sequencing analysis (RNA-seq) and network pharmacology analyses were conducted to elucidate the molecular mechanisms. Our results showed that MIRI caused cardiac structural and functional damage in rats. MIRI promoted ferroptosis, which was consistently observed in vitro. However, pretreatment with OA reversed these effects. The mitogen-activated protein kinases (MAPK) signaling pathway participated in the MIRI process, with dual-specificity phosphatase 10 (DUSP10) found to regulate it. Further confirmation was provided by knocking down DUSP10 using small interfering RNA (siRNA), demonstrating the activation of the DUSP10/MAPK-Nrf2 pathway by OA to protect H9C2 cells from ferroptosis. Our research has demonstrated the mitigating effect of OA on MIRI and the improvement of myocardial function for the first time. The inhibition of ferroptosis has been identified as one of the mechanisms through which OA exerts its myocardial protective effects. Moreover, we have first unveiled that DUSP10 serves as an upstream target involved in mediating ferroptosis, and the regulation of the DUSP10/MAPK-Nrf2 pathway by OA is crucial in inhibiting ferroptosis to protect the myocardium., (© 2024 John Wiley & Sons, Ltd.)

After myocardial ischemia/reperfusion injury (MI/RI), endothelial cell injury causes impaired angiogenesis and obstruction of microcirculation, resulting in an inflammatory outburst that exacerbates the damage. Therefore, synergistic blood vessel repair and inflammation inhibition are effective therapeutic strategies. In this study, we developed a platelet membrane (PM)-encapsulated baicalin nanocrystalline (BA NC) nanoplatform with a high drug load, BA NC@PM, which co-target to endothelial cells and macrophages through the transmembrane proteins of the PM to promote angiogenesis and achieve anti-inflammatory effects. In vitro cell scratch assays and transwell assay manifested that BA NC@PM could promote endothelial cell migration, as well as increase mRNA expression of CD31 and VEGF in the heart after treatment of MI/RI mice, suggesting its favorable vascular repair function. In addition, the preparation significantly reduced the expression of pro-inflammatory factors and increased the expression of anti-inflammatory factors in plasma, promoting the polarization of macrophages. Our study highlights a strategy for enhancing the treatment of MI/RI by promoting angiogenesis and regulating macrophage polarization via the biomimetic BA NC@PM nanoplatform., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Abstract: Ischemic heart disease gravely threatens human health and even results in death. Kirenol is predominantly derived from the Herba Siegesbeckiae plant species and possesses a wide range of biological effects (such as antibacterial, anti-inflammatory, anticancer, and cardioprotective). However, the regulatory effects and associated mechanisms of kirenol in myocardial ischemia/reperfusion injury (MI/RI) remain unclear. In this study, first, the MI/RI rat model was established. It was demonstrated that kirenol protected against the aggravation of cardiac function in MI/RI rats. In addition, the inflammation was induced by ischemia reperfusion (IR), which was likewise affected by kirenol (5 or 10 mg/kg). Moreover, IR enhanced oxidative stress, a process that was counteracted by kirenol. Next, cell apoptosis was discovered to be heightened after IR, but this effect was neutralized by kirenol. Finally, it was revealed that kirenol has the ability to block the activation of the NF-κB pathway. In conclusion, it was disclosed that kirenol alleviated inflammation and oxidative stress through modulating the NF-κB pathway to improve MI/RI in rats. This work may offer novel insights for searching useful drugs for treating MI/RI., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Ferroptosis is a newly defined mode of cellular demise. The increasing investigation supports that ferroptosis is a crucial factor in the complex mechanisms of myocardial ischemia-reperfusion (I/R) injury. Hence, targeting ferroptosis is a novel strategy for treating myocardial injury. Although evidence suggests that trimetazidine (TMZ) is potentially efficacious against myocardial injury, the exact mechanism of this efficacy is yet to be fully elucidated. This study aimed to determine whether TMZ can act as a ferroptosis resistor and affect I/R-mediated myocardial injury. To this end, researchers have constructed in vitro and in vivo models of I/R using H9C2 cardiomyocytes, primary cardiomyocytes, and SD rats. Here, I/R mediated the onset of ferroptosis in vitro and in vivo, as reflected by excessive iron aggregation, GSH depletion, and the increase in lipid peroxidation. TMZ largely reversed this alteration and attenuated cardiomyocyte injury. Mechanistically, we found that TMZ upregulated the expression of Sirt3. Therefore, we used si-Sirt3 and 3-TYP to interfere with Sirt3 action in vitro and in vivo, respectively. Both si-Sirt3 and 3-TYP partly mitigated the inhibitory effect of TMZ on I/R-mediated ferroptosis and upregulated the expression of Nrf2 and its downstream target, GPX4-SLC7A11. These results indicate that TMZ attenuates I/R-mediated ferroptosis by activating the Sirt3-Nrf2/GPX4/SLC7A11 signaling pathway. Our study offers insights into the mechanism underlying the cardioprotective benefits of TMZ and establishes a groundwork for expanding its potential applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Introduction: Ginsenosides (GS) derived from Panax ginseng can regulate protein acetylation to promote mitochondrial function for protecting cardiomyocytes. However, the potential mechanisms of GS for regulating acetylation modification are not yet clear., Objectives: This study aimed to explore the potential mechanisms of GS in regulating protein acetylation and identify ginsenoside monomer for fighting myocardial ischemia-related diseases., Methods: The 4D-lable free acetylomic analysis was employed to gain the acetylated proteins regulated by GS pretreatment. The co-immunoprecipitation assay, immunofluorescent staining, and mitochondrial respiration measurement were performed to detect the effect of GS or ginsenoside monomer on acetylated protein level and mitochondrial function. RNA sequencing, site-specific mutation, and shRNA interference were used to explore the downstream targets of acetylation modificationby GS. Cellular thermal shift assay and surface plasmon resonance were used for identifying the binding of ginsenoside with target protein., Results: In the cardiomyocytes of normal, oxygen glucose deprivation and/or reperfusion conditions, the acetylomic analysis identified that the acetylated levels of spliceosome proteins were inhibited by GS pretreatment and SF3A2 acetylation at lysine 10 (K10) was significantly decreased as a potential target of GS. Ginsenoside Rb2 was identified as one of the active ginsenoside monomers for reducing the acetylation of SF3A2 (K10), which enhanced mitochondrial respiration against myocardial ischemic injury in in vivo and in vitro experiments. RNA-seq analysis showed that ginsenoside Rb2 promoted alternative splicing of mitochondrial function-related genes and the level of fascin actin-bundling protein 1 (Fscn1) was obviously upregulated, which was dependent on SF3A2 acetylation. Critically, thermodynamic, kinetic and enzymatic experiments demonstrated that ginsenoside Rb2 directly interacted with p300 for inhibiting its activity., Conclusion: These findings provide a novel mechanism underlying cardiomyocyte protection of ginsenoside Rb2 by inhibiting p300-mediated SF3A2 acteylation for promoting Fscn1 expression, which might be a promising approach for the prevention and treatment of myocardial ischemic diseases., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Production and hosting by Elsevier B.V.)

Objective: To explore the role and mechanism of metformin (MET) in regulating myocardial injury caused by cardiac ischemia-reperfusion., Material and Methods: A rat model of myocardial ischemia-reperfusion injury was established by ligation of the anterior descending branch of the left coronary artery. The myocardial area at risk and the infarction size were measured by Evans blue and 2,3,5‑triphenyltetrazole chloride (TTC) staining, respectively. Terminal Deoxynucleotidyl Transferase-Mediated dUTP Nick End Labeling (TUNEL) staining was used to detect apoptosis of cardiomyocytes. The expression of 4‑hydroxynonenal (4‑HNE) was detected by immunohistochemical staining. Real-time quantitative polymerase chain reaction (RT-PCR) and Western blot were used to detect mRNA and expression of the Adenosine 5'-monophosphate-activated protein kinase (AMPK) - 3‑hydroxy-3‑methylglutaryl-CoA reductase (HMGCR) signaling pathway, respectively., Results: MET treatment decreased the infarct size and the activity of the myocardial enzyme profile, thus demonstrating protection of ischemic myocardium. The number of TUNEL positive cells significantly decreased. Immunohistochemical results showed that MET decreased the expression of 4‑HNE in myocardial tissue and the content of malondialdehyde (MDA) in myocardial cells. Further experimental results showed that MET decreased HMGCR transcription and protein expression, and increased AMPK phosphorylation. In the model of hypoxia and reoxygenation injury of cardiomyocytes, MET increased the viability of cardiomyocytes, decreased the activity of lactic dehydrogenase (LDH), decreased malondialdehyde content and intracellular reactive oxygen species (ROS) concentrations, and regulate the AMPK-HMGCR signaling pathway through coenzyme C (ComC)., Conclusion: MET inhibits the expression of HMGCR by activating AMPK, reduces oxidative damage and apoptosis of cardiomyocytes, and alleviates myocardial ischemia-reperfusion injury.

Background: The aim of our study was to test different anesthetic mixtures in order to identify the most suitable one for a surgical cardiac ischemia-reperfusion model in mice., Methods: 1) Sixty four mice were submitted to one of the 6 combinations of ketamine or alfaxalone associated to xylazine, medetomidine or midazolam. Depth and quality of anesthesia were evaluated via 5 reflex scores. 2) Impact of analgesic (buprenorphine or butorphanol), anesthesia reversal (with atipamezole) and surgery (cardiac ischemia-reperfusion surgery) have been tested in the selected protocols. 3) infarction size has been measured with TTC (Triphenyl Tetrazolium Chloride) method in mice anesthetized with best protocols., Results: Protocol involving medetomidine induced the longest surgical anesthesia: (median = 120, {interquartile range = 100-125}) min with ketamine and 53 {25-100} min with alfaxalone. Butorphanol substitution with buprenorphine did not alter time-related anesthesia parameters. Atipamezole reversal considerably reduced both recovery and immobilization time (respectively 22 {18-30} min and 98 {88-99} min vs. 55 {40-70} min and 143 {131-149} min, in groups with no reversal, p = 0.001) with no impact on infarction size measurement., Conclusion: In this study, the combination alfaxalone/medetomidine/buprenorphine (80/0,3/0,075 mg.kg-1, s.c.) associated with reversal by atipamezole was a reliable anesthetic protocol for murine surgery, particularly for the study of ischemia-reperfusion., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Leon et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Effective treatment of myocardial ischemia-reperfusion (MIR) injury remains an unmet clinical need. Cardiomyocyte apoptosis is common at this stage and poses a significant risk. Corylin, a flavonoid compound extracted from Psoralea corylifolia L., has been shown to have anti-inflammatory, anticancer, and antiatherosclerotic properties. However, whether and how corylin affects MIR injury remain unclear. In this study, we explored the mechanism of corylin as a potent therapeutic agent for MI/R injury, using a left anterior descending (LAD) coronary artery ligation and oxygen-glucose deprivation and reperfusion (OGD/R) model in vivo and in vitro. TUNEL, Annexin-V/PI double staining,Ki67 immunohistochemistry, western blot analysis, and immunofluorescence were used to validate cell apoptosis level and Raf-1/ASK1 complex activity. The interaction between corylin and Raf-1/ASK1 complex was detected using molecular docking, corylin-Raf-1 binding assays, and coimmunoprecipitation (Co-IP). Moreover, TTC staining, echocardiography, HE staining, Masson trichrome staining and serological testing were performed to assess the cardioprotective effects of corylin in vivo. These findings showed that corylin reduces MIR injury-induced cardiomyocyte apoptosis and improves cardiac function. Mechanistically, corylin can interact with Raf-1 and promote the formation of the Raf-1/ASK1 complex, thus inhibiting cardiomyocyte apoptosis. In conclusion, our results demonstrate that corylin ameliorated cardiac dysfunction after MIR injury by reducing myocardial apoptosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Pharmacological preconditioning is an alternative to protect the heart against the consequences of damage from ischemia/reperfusion (I/R). It is based on the administration of specific drugs that imitate the effect of ischemic preconditioning (IPC). Peroxisomal proliferator-activated receptors (PPARs) can prevent apoptosis in pathologies such as I/R and heart failure. Therefore, our objective was to determine if the stimulation of PPARα with fenofibrate (feno) decreases the apoptotic process induced by hypoxia/reoxygenation (HR), high glucose (HG), and HR/HG. For that purpose, cardiomyocyte cultures were divided into the following groups: Group 1-control (Ctrl); Group 2-HR; Group 3-HR + 10 μM feno; Group 4-HG, (25 mM glucose); Group 5-HG + feno; Group 6-HR/HG, and Group 7-HR/HG + feno. Our results indicate that cell viability decreases in neonatal cardiomyocytes undergoing HR, HG, and their combination, while feno improved cell viability. Feno treatment decreased apoptosis compared with HG-, HR-, or HG/HR-vehicle-treated. Nuclear- and mitochondrial-apoptosis markers increased in neonatal cardiomyocytes from HR, HG, and HR/HG; while the cytotoxicity decreased in cells treated with feno. In addition, the expression of Bax, Bad, and caspase 9 decreased due to feno, while 14-3-3ɛ and Bcl2 were increased. Inner mitochondrial cytochrome C increased with feno in every condition, as well as mitochondrial activity. Feno treatment prevented injury in the ultrastructure and in the mitochondrial membranes. Thus, our results suggest that feno decreases apoptosis in neonatal cardiomyocytes, improving the ultrastructure of mitochondria in the pathological conditions studied.

Myocardial ischemia-reperfusion (IR) injury is a severe rhythmic disease with a high prevalence in the early morning. IR injury has a significant circadian rhythm in reactive oxygen species (ROS) and inflammation levels. The development of rhythmic drugs has become a priority in myocardial IR injury. In this study, resveratrol (RES) and proanthocyanidins (OPC) were utilized to design nanoparticles (NPs), with hyaluronic acid (HA) as the core, grafted with MMP-targeting peptides to improve delivery to injured myocardial regions (HA-RES-OPC-MMP NPs). NPs significantly scavenged ROS, attenuated inflammation, and activated the rhythm gene. Notably, the difference in therapeutic effects on myocardial IR injury in mice at Zeitgeber time (ZT)1 and ZT13 confirms that NPs are rhythm-dependent drugs. At ZT13, echocardiographic and MRI confirm that IR injury in mice was not as severe as at ZT1, yet NPs were also less effective in treatment. Further, Per1/2 knockout mice confirmed the rhythm-dependent treatment of myocardial IR injury by NPs. Molecular studies have shown that rhythmic characteristics of inflammation and Sirt1 transcript levels are the main reasons for the different rhythmic therapeutic effects of NPs. Circadian rhythm-dependent treatment of HA-RES-OPC-MMP NPs has excellent potential for more precise treatment of myocardial IR injury in the future.

Tilianin (TIL), a bioactive component derived from Dracocephalum Moldavica L., has been recognized for its anti-inflammatory properties. However, its effects on the Nlrp3 inflammasome within endothelial progenitor cells (EPCs) during myocardial ischemia-reperfusion injury (MIRI) remain unexplored. This study aimed to elucidate the role of TIL in modulating Nlrp3 inflammasome activation under MIRI conditions. A mouse model of MIRI was established to assess the therapeutic potential of TIL. EPCs treated with TIL at concentrations of 5, 10, and 20 μM were administered into the myocardium before reperfusion. Additionally, the cardioprotective effects of TIL were further examined by pre-treating EPCs with the compound before exposing them to hypoxia/reoxygenation (H/R) using cardiomyocyte supernatants. The impact on Nlrp3 inflammasome was assessed through western blotting, immunofluorescence, and ELISA. Our results showed that TIL concentration-dependently inhibited Nlrp3 inflammasome-related protein levels,and inhibited Asc oligomerization and Asc-Speck complex formation in EPCs, resulting in improved the migratory capacity and vascular structure formation of EPCs. In addition, TIL-treated EPCs significantly attenuated I/R injury and improved cardiac function. These results suggest that TIL ameliorates the inflammatory response in EPCs by suppressing Nlrp3 inflammasome activation, thereby facilitating neovascularization in the myocardium and conferring protection against MIRI. The study provides valuable insights into the potential of TIL as a therapeutic agent for cardiovascular diseases linked to ischemia-reperfusion injury., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Wang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The effects of Gastrodin (GD) on cerebral ischemia stimulated researchers to investigate its possible role in the progression of arrhythmia associated with cardiac ischemia-reperfusion (IR) damage in rats. 40 Sprague-Dawley rats were divided into four groups: Sham, Model, GD 50 mg/kg, and GD 100 mg/kg. Myocardial ischemia (MI) was caused by the procedure of ligating the left coronary artery, followed by reperfusion. Heart rate (HR), mean arterial pressure (MAP), and rate pressure product (RPP) in rats were assessed before and after ischemia and reperfusion, as well as cardiac arrhythmia in experimental rats. The I/R damage was evaluated by measuring levels of Na + -K + ATPase and Ca 2+ -Mg 2+ ATPase, Creatine Kinase-MB (CK-MB), Cardiac Troponin I (cTnI), Gap Junction α-1 (GJα-1), Phospho-GJα-1/total-GJα-1, Kir2.1, Bax, Bcl-2, and oxidative indicators. MGL's Autodock and Vina programs were used for in silico docking studies to identify possible interactions between GJα-1 and Gastrodin. The animals in the model group expressed a substantial decrease in HR, MAP, and RPP compared to the Sham group. GD-treated rats revealed slightly higher values compared to the model group. Expression of CK-MB and cTnI was reduced, and Na + -K + ATPase and Ca 2+ -Mg 2+ ATPase expression was increased on GD pre-conditioning. Phospho-Cx43/total-Cx43 ratio and Bax expression were increased, whereas GD reduced Bcl-2 expression. In silico molecular docking studies suggested the potential binding of GD with the GJα-1 protein, thus confirming the in vivo results. GD corrected the arrhythmia in rats subjected to I/R injury by increasing Na + -K + ATPase and Ca 2+ -Mg 2+ ATPase expression, targeting GJα-1, and modulating the expression of Kir2.1.

Background: Myocardial ischemia/reperfusion (I/R) injury stands as a primary contributor to ischemic heart disease. Sevoflurane (SEVO), a commonly used inhalation anesthetic, has been shown to exert a direct protective effect on ischemic heart injury. However, the specific mechanism by which it exerts the protective effect remains unclear. This study was designed to investigate the role of SEVO in myocardial I/R injury and its potential molecular mechanisms., Methods: Blood samples were collected from patients with acute myocardial infarction (AMI) (n = 20) and healthy volunteers (n = 20). The human cardiomyocytes AC16 models of I/R injury were induced by hypoxia/reoxygenation. The mRNA expression levels of growth differentiation factor 11 ( GDF11 ) in the cells and blood were determined by reverse transcription quantitative real-time PCR (RT-qPCR). The cell proliferation was detected by Cell Counting Kit-8 (CCK-8). Enzyme-Linked Immunosorbent Assay (ELISA) was utilized to detect the levels of inflammatory factors interleukin (IL)-8, IL-1β and IL-6 in the cells. And biochemical assay kits were applied for the measurement of the activity of lactate dehydrogenase (LDH) and superoxide dismutase (SOD) as well as the malondialdehyde (MDA) level in the cells. Moreover, western blot was employed to evaluate the levels of the p-serine-threonine protein kinase (AKT), AKT, and phosphatidylinositol 3-kinase (PI3K), protein expression in the cells., Results: The GDF11 expression was decreased in the blood of AMI patients and cardiomyocytes induced by I/R ( p < 0.01). Besides, 1% SEVO was presented to promote cardiomyocyte proliferation, inhibit apoptosis, oxidative stress and inflammation, and activate the PI3K/AKT signaling pathway through up-regulation of GDF11 expression ( p < 0.01)., Conclusion: SEVO promotes proliferation and inhibits inflammatory response, apoptosis, and oxidative stress of I/R-treated cardiomyocytes by elevating GDF11 expression, thereby reducing myocardial I/R injury. Notably, the mechanism underlying the alleviation of the I/R injury may involve the activation of PI3K/AKT signaling pathway.

Background: Ferroptosis is an important type of cell death contributing to myocardial dysfunction induced by whole body ischemia reperfusion following cardiac arrest (CA) and resuscitation. Sulforaphane (SFN), known as the activator of the nuclear factor E2-related factor 2 (Nrf2), has been proven to effectively alleviate regional myocardial ischemia reperfusion injury. The present study was designed to investigate whether SFN could improve post-resuscitation myocardial dysfunction by inhibiting cardiomyocytes ferroptosis and its potential regulatory mechanism., Methods and Results: An in vivo pig model of CA and resuscitation was established. Hypoxia/reoxygenation (H/R)-stimulated AC16 cardiomyocytes was constructed as an in vitro model to simulate the process of CA and resuscitation. In vitro experiment, SFN reduced ferroptosis-related ferrous iron, lipid reactive oxygen species, and malondialdehyde, increased glutathione, and further promoted cell survival after H/R stimulation in AC16 cardiomyocytes. Mechanistically, the activation of Nrf2 with the SFN decreased interferon regulatory factor 1 (IRF1) expression, then reduced its binding to the promoter of glutathione peroxidase 4 (GPX4), and finally recovered the latter's transcription after H/R stimulation in AC16 cardiomyocytes. In vivo experiment, SFN reversed abnormal expression of IRF1 and GPX4, inhibited cardiac ferroptosis, and improved myocardial dysfunction after CA and resuscitation in pigs., Conclusions: SFN could effectively improve myocardial dysfunction after CA and resuscitation, in which the mechanism was potentially related to the inhibition of cardiomyocytes ferroptosis through the regulation of Nrf2/IRF1/GPX4 pathway., Competing Interests: Declaration of Competing Interest The authors have declared no conflict of interest, (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Delivering therapeutic agents efficiently to inflamed regions remains an intractable challenge following myocardial ischemia-reperfusion injury (MI/RI) due to the transient nature of the enhanced permeability and retention effect, which disappears after 24 h. Leveraging the inflammation-homing and plasticity properties of circulating monocytes (MN) as hitchhiking carriers and further inducing their polarization into anti-inflammatory phenotype macrophages upon reaching the inflamed sites is beneficial for MI/RI therapy. Herein, DSS/PB@BSP nanoparticles capable of clearing reactive oxygen species and inhibiting inflammation were developed by employing hollow Prussian blue nanoparticles (PB) as carriers to encapsulate betamethasone sodium phosphate (BSP) and further modified with dextran sulfate sodium (DSS), a targeting ligand for the scavenger receptor on MN. This formulation was internalized into MN as living cell drug depots, reprogramming them into anti-inflammation type macrophages to inhibit inflammation. In vitro assessments revealed the successful construction of the nanoparticle. In a murine MI/RI model, circulating MN laden with these nanoparticles significantly enhanced drug delivery and accumulation at the cardiac injury site, exhibiting favorable therapeutic ability and promoting M2-biased differentiation. Our study provides an effective approach with minimally invasion and biosecurity that makes this nanoplatform as a promising candidate for immunotherapy and clinical translation in the treatment of MI/RI., Competing Interests: Declaration of competing interest The author reports no conflicts of interest in this work., (Copyright © 2024. Published by Elsevier B.V.)

This study investigates the protective effects of propofol on the myocardium by inhibiting the expression of SLC16A13 through in vivo animal experiments, while also exploring its mechanism in ferroptosis to provide new strategies for preventing perioperative myocardial ischemia-reperfusion injury. We randomly divided 30 rats into three groups (n=10 each): sham surgery group, ischemia-reperfusion (I/R) group, and propofol pretreatment group. The results showed that compared with the sham surgery group, the I/R group had a significant decrease in cardiac function and an increase in infarct size. Propofol pretreatment effectively alleviated the damage caused by ischemia-reperfusion (I/R). In the next phase of the study, we administered the PPARα agonist GW7647 to artificially increase the expression of SLC16A13. Fifty rats were randomly divided into five groups (n=10 each), with the GW7647 pretreatment group and propofol+GW7647 pretreatment group added based on the previous three groups. Afterwards, we validated the in vivo results using H9C2 and further explored the mechanism by which propofol inhibits ferroptosis. The study found that L-lactic acid in myocardial tissue of the GW7647 group was further increased compared to the I/R group, and the degree of ferroptosis was aggravated. In addition, upregulation of SLC16A13 significantly inhibited the phosphorylation of AMPK, weakened the protective mechanism of AMPK, and exacerbated cardiac damage. However, propofol pretreatment can effectively inhibit the expression of SLC16A13, maintain normal myocardial cell morphology, and protect cardiac function. These results indicate that propofol inhibits the expression of SLC16A13, alleviates myocardial cell ferroptosis via the AMPK/GPX4 pathway, and reverses damage caused by myocardial ischemia-reperfusion., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Background: Although blood flow is restored after treatment of myocardial infarction (MI), myocardial ischemia and reperfusion (I/R) can cause cardiac injury, which is a leading cause of heart failure. Gastrodin (GAS) exerts protective effects against brain, heart, and kidney I/R. However, its pharmacological mechanism in myocardial I/R injury (MIRI) remains unclear., Purpose: GAS regulates autophagy in various diseases, such as acute hepatitis, vascular dementia, and stroke. We hypothesized that GAS could repair mitochondrial damage and regulate autophagy to protect against MIRI., Study Design: Male C57BL/6 mice and H9C2 cells were subjected to I/R and hypoxia-reoxygenation (H/R) injury after GAS administration, respectively, to assess the impact of GAS on cardiomyocyte phenotypes, heart, and mitochondrial structure and function. The effect of GAS on cardiac function and mitochondrial structure in patients undergoing cardiac surgery has been observed in clinical practice., Methods: The effects of GAS on cardiac structure and function, mitochondrial structure, and expression of related molecules in an animal model of MIRI were evaluated using immunohistochemical staining, enzyme-linked immunosorbent assay (ELISA), transmission electron microscopy, western blotting, and gene sequencing. Its effects on the morphological, molecular, and functional phenotypes of cardiomyocytes undergoing H/R were observed using immunohistochemical staining, real-time quantitative PCR, and western blotting., Results: GAS significantly reduces myocardial infarct size and improves cardiac function in MIRI mice in animal models and increases cardiomyocyte viability and reduces cardiomyocyte damage in cellular models. In clinical practice, myocardial injury was alleviated with better cardiac function in patients undergoing cardiac surgery after the application of GAS; improvements in mitochondria and autophagy activation were also observed. GAS primarily exerts cardioprotective effects through activation of the PINK1/Parkin pathway, which promotes mitochondrial autophagy to clear damaged mitochondria., Conclusion: GAS can promote mitophagy and preserve mitochondria through PINK1/Parkin, thus indicating its tremendous potential as an effective perioperative myocardial protective agent., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier GmbH.. All rights reserved.)

Acute myocardial infarction (AMI), characterized by high incidence and mortality rates, poses a significant public health threat. Reperfusion therapy, though the preferred treatment for AMI, often exacerbates cardiac damage, leading to myocardial ischemia/reperfusion injury (MI/RI). Consequently, the development of strategies to reduce MI/RI is an urgent priority in cardiovascular therapy. Chinese medicine, recognized for its multi-component, multi-pathway, and multi-target capabilities, provides a novel approach for alleviating MI/RI. A key area of interest is the nuclear factor E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. This pathway is instrumental in regulating inflammatory responses, oxidative stress, apoptosis, endoplasmic reticulum stress, and ferroptosis in MI/RI. This paper presents a comprehensive overview of the Nrf2/HO-1 signaling pathway's structure and its influence on MI/RI. Additionally, it reviews the latest research on leveraging Chinese medicine to modulate the Nrf2/HO-1 pathway in MI/RI treatment., (© 2024. The Chinese Journal of Integrated Traditional and Western Medicine Press and Springer-Verlag GmbH Germany, part of Springer Nature.)

Acute myocardial infarction, often associated with ischemia/reperfusion injury (I/R), is a leading cause of death worldwide. Although the endogenous tryptophan metabolite kynurenic acid (KYNA) has been shown to exert protection against I/R injury, its mechanism of action at the cellular and molecular level is not well understood yet. Therefore, we examined the potential involvement of antiapoptotic mechanisms, as well as N-methyl-D-aspartate (NMDA) receptor modulation in the protective effect of KYNA in cardiac cells exposed to simulated I/R (SI/R). KYNA was shown to attenuate cell death induced by SI/R dose-dependently in H9c2 cells or primary rat cardiomyocytes. Analysis of morphological and molecular markers of apoptosis (i.e., membrane blebbing, apoptotic nuclear morphology, DNA double-strand breaks, activation of caspases) revealed considerably increased apoptotic activity in cardiac cells undergoing SI/R. The investigated apoptotic markers were substantially improved by treatment with the cytoprotective dose of KYNA. Although cardiac cells were shown to express NMDA receptors, another NMDA antagonist structurally different from KYNA was unable to protect against SI/R-induced cell death. Our findings provide evidence that the protective effect of KYNA against SI/R-induced cardiac cell injury involves antiapoptotic mechanisms, that seem to evoke independently of NMDA receptor signaling., (© 2024. The Author(s).)

MAPKK4 has been implicated in the pathological mechanisms underlying myocardial and vascular injury, specifically influencing endothelial cell damage and programmed cell death via subcellular pathways. Nevertheless, the regulatory role of MAPKK4 in coronary microvascular injury following myocardial infarction remains unconfirmed, and the exploration of targeted mitochondrial protective therapeutic agents remains unaddressed. In light of this gap, we established a MAPKK4 gene-modified mouse model of ischemia-reperfusion injury and employed Buyang Huanwu decoction (BYHW), a traditional cardiovascular therapeutic formula, to assess its efficacy in treating coronary microvascular injury post-ischemia-reperfusion. The study aimed to elucidate the mechanism by which BYHW mitigates coronary microvascular injury induced by ischemia-reperfusion through the attenuation of endothelial cell apoptosis. Experimental outcomes revealed that high-dose BYHW significantly ameliorated coronary microvascular injury post-ischemia-reperfusion, restoring the structural integrity of the coronary microvasculature and reducing inflammation and oxidative stress. Contrarily, in transgenic mice overexpressing MAPKK4, BYHW intervention failed to attenuate microvascular inflammation and oxidative stress. To further investigate, we simulated hypoxia/reoxygenation injury in vascular endothelial cells using a MAPKK4-related cellular gene modification model. The results indicated that BYHW attenuates inflammatory damage and enhances the viability of vascular endothelial cells following hypoxic stress, inhibiting apoptosis via the mitochondrial pathway. However, overexpression of MAPKK4/p38 negated the therapeutic effects of BYHW, showing no impact on endothelial cell apoptosis and oxidative stress under hypoxic conditions. Molecular interaction studies confirmed that the active components of BYHW, Astragaloside IV and Ligustrazine, interact with the MAPKK4/P38 axis. In vitro experiments further suggested that the interaction between MAPKK4 and P38 play a crucial role in the ability of BYHW to inhibit apoptosis in coronary microvascular endothelial cells. Therapeutically, MAPKK4 may potentiate the apoptotic pathway in microvascular endothelial cells by modulating downstream P38 expression and phosphorylation, thereby exacerbating ischemia-reperfusion-induced coronary microvascular endothelial injury. From an in vivo perspective, the transgenic overexpression of MAPKK4 and P38 inhibited the microvascular protective effects of BYHW. These findings collectively underscore the significance of the MAPKK4-P38 axis in the protection of coronary microvascular endothelial cells., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Objective: This study aimed to demonstrate whether ozone has cardioprotective effects on the myocardial ischemia-reperfusion injury (IRI) in rats with streptozotocin(STZ)-induced diabetes., Methods: A total of 38 male Wistar Albino rats were divided into five groups as follows: control group (group C, n =6), diabetic group (group D, n =6), diabetic ozone group (group DO,n=6), diabetic-ischemia/reperfusion (group DIR, n =6), diabetic-ischemia/reperfusion-ozone (group DIRO, n =6). Six rats died during this period and two died because of surgical complications. A myocardial ischemia-reperfusion model was created using a thoracotomy incision from 4th intercostal space. The LAD was ligated using an 8-0 prolene suture for 30min. Ozone was administered intraperitoneally(1mg/kg) 5min before reperfusion. The reperfusion time was 120 min. At the end of the reperfusion procedure, myocardial tissue histopathological examinations, and serum biochemical analyses were performed., Results: The percentage of TUNEL(+) cardiomyocytes/HPF was significantly higher in the DIR group than in the C, D, and DO groups. Conversely, TUNEL positivity was significantly lower in the DIRO group than in the DIR group. The IRI score was significantly higher in the DIR and DIRO groups than that in the C, D, and DO groups. In contrast, the IRI damage score in the DIRO group was significantly lower than that in the DIR group. Serum MDA levels were significantly higher in the DIR group than in the C, D, and DO groups. Similarly, MDA levels were significantly higher in the DIRO group than in the C and D groups. CAT activity was significantly higher in the DIR group than in the C and D groups. SOD activity was significantly higher in the DIR group than in the C and DO groups., Conclusion: Our study showed that ozone exerts cardioprotective effects in STZ-induced diabetic rats through its antioxidant role against oxidative stress. Both biochemical and histological analyses clearly revealed that ozone has beneficial effects against IRI in the diabetic rat myocardium., Competing Interests: The authors declare no conflicts of interest in this work., (© 2024 Gülcan et al.)

Dexmedetomidine (Dex) is widely used in the sedation in intensive care units and as an anesthetic adjunct. Considering the anti-inflammatory and antioxidant properties of Dex, we applied in vivo rat model as well as in vitro cardiomyocyte models (embryonic rat cardiomyocytes H9c2 cells and neonatal rat cardiomyocytes, NRCMs) to evaluate the effects of Dex against myocardial ischemia reperfusion (I/R) injury. Transcriptomic sequencing for gene expression in heart tissues from control rats and Dex-treated rats identified that genes related to fatty acid metabolism were significantly regulated by Dex. Among these genes, the elongation of long-chain fatty acids (ELOVL) family member 6 (Elovl6) was most increased upon Dex-treatment. By comparing the effects of Dex on both wild type and Elovl6-knockdown H9c2 cells and NRCMs under oxygen-glucose deprivation/reoxygenation (OGD/R) challenge, we found that Elovl6 knockdown attenuated the protection efficiency of Dex, which was supported by the cytotoxicity endpoints (cell viability and lactate dehydrogenase release) and apoptosis as well as key gene expressions. These results indicate that Dex exhibited the protective function against myocardial I/R injury via fatty acid metabolism pathways and Elovl6 plays a key role in the process, which was further confirmed using palmitate exposure in both cells, as well as in an in vivo rat model. Overall, this study systematically evaluates the protective effects of Dex on the myocardial I/R injury and provides better understanding on the fatty acid metabolism underlying the beneficial effects of Dex., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In myocardial infarction, ischemia-reperfusion injury (IRI) poses a significant challenge due to a lack of effective treatments. Bilirubin, a natural compound known for its anti-inflammatory and antioxidant properties, has been identified as a potential therapeutic agent for IRI. Currently, there are no reports about proteomic studies related to IRI and bilirubin treatment. In this study, we explored the effects of bilirubin nanoparticles in a rat model of myocardial IRI. A total of 3616 protein groups comprising 76,681 distinct peptides were identified using LC-MS/MS, where we distinguished two kinds of protein groups: those showing increased expression in IRI and decreased expression in IRI with bilirubin treatment, and vice versa, accounting for 202 and 35 proteins, respectively. Our proteomic analysis identified significant upregulation in the Wnt and insulin signaling pathways and increased Golgi markers, indicating their role in mediating bilirubin nanoparticle's protective effects. This research contributes to the proteomic understanding of myocardial IRI and suggests bilirubin nanoparticles as a promising strategy for cardiac protection, warranting further investigation in human models.

Fucoxanthin (Fx), a xanthophyll carotenoid abundant in brown algae, possesses several biological functions, such as antioxidant, anti-inflammatory, and cardiac-protective activities. However, the role of Fx in myocardial ischemia/reperfusion (MI/R) is still unclear. Thus, the aim of this study was to investigate the effect of Fx on MI/R-induced injury and explore the underlying mechanisms. Our results showed that in vitro, Fx treatment significantly suppressed inflammatory response, oxidative stress, and apoptosis in rat cardiomyocytes exposed to hypoxia/reoxygenation (H/R). In addition, Fx led to increased phosphorylation of AMPK, AKT, and GSK-3β, and enhanced activation of Nrf2 in cardiomyocytes under H/R conditions. Notably, pretreatment with Compound C (AMPK inhibitor), partially reduced the beneficial effects of Fx in cardiomyocytes exposed to H/R. In vivo, Fx ameliorated myocardial damage, inhibited inflammatory response, oxidative stress, and apoptosis, and activated the AMPK/GSK-3β/Nrf2 signaling in myocardial tissues in MI/R rat model. Taken together, these findings indicated that Fx attenuates MI/R-induced injury by inhibiting oxidative stress, inflammatory response, and apoptosis. The AMPK/GSK-3β/Nrf2 pathway is involved in the cardioprotective effect of Fx in MI/R injury. Thus, Fx may be a promising drug for the treatment of MI/R., (© 2024 John Wiley & Sons Ltd.)

Gastric precancerous lesion (GPL) is a crucial stage in the development of gastric cancer, characterized by incomplete intestinal epithelial chemotaxis and heterogeneous hyperplasia with high malignant potential. Early intervention in GPL is vital for preventing gastric cancer. Additionally, there are shared risk factors and pathogenesis between tumors and coronary heart disease (CHD), with an increasing number of tumor patients GPL complicated with CHD due to improved survival rates. Reperfusion therapy in CHD can result in myocardial ischemia-reperfusion injury (MIRI). Traditional Chinese medicine (TCM) has demonstrated unique advantages in treating GPL and MIRI by promoting blood circulation and removing blood stasis. Panax ginseng total saponin (PNS), a component of TCM known for its blood circulation benefits, has shown positive effects in inhibiting tumor growth and improving myocardial ischemia. This study utilized a GPL-MIRI mouse model to investigate the effects of PNS in treatment. Results indicated that PNS significantly improved typical GPL lesions in mice, such as incomplete intestinal epithelialization and heteroplasia, and also reduced myocardial infarction. At the molecular level, PNS exhibited a bidirectional regulatory role in the GPL-MIRI model. It enhanced the autophagic process in gastric mucosal cells by inhibiting the PI3K/Akt/mTOR signaling pathway, while suppressed excessive autophagy in cardiomyocytes. These findings offer new insights and treatment strategies for managing GPL and MIRI using the TCM compound PNS., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Masson SAS.)

Introduction: Acute hyperglycemia (HG) enhances inflammatory and oxidative stress and exacerbates myocardial infarct size during ischemia-reperfusion injury by activating splenic leukocytes. Formyl peptide receptor 1 (FPR1) on leukocytes is activated by and mediates myocardial ischemia-reperfusion injury. We hypothesize that selective FPR1 antagonist cinnamoyl-F-(D)L-F-(D)L-F (CF) or potent reducing agent tris (2-carboxyethyl) phosphine hydrochloride (TCEP) could abrogate hyperglycemic infarct exacerbation, both alone and synergistically via a novel CF-TCEP compound that would target leukocytes for antioxidative effect., Methods: Acute HG was induced in wild type mice with an intraperitoneal dextrose injection followed by left coronary artery occlusion (30 min) and reperfusion (60 min). In treatment groups, CF (0.1 mg/kg or 1 mg/kg), TCEP (1 mg/kg or 20 mg/kg), or the CF-TCEP conjugate (0.1 mg/kg) was administered intravenously before reperfusion. The hearts were harvested to measure infarct size (IF)., Results: HG resulted in >50% increase in IF compared to euglycemic mice (52.1 ± 3.0 versus 34.0 ± 3.2%, P < 0.05). Neither CF nor TCEP independently exerted an infarct-sparing effect at lower doses (46.2 ± 2.1% or 50.9 ± 4.1%, P > 0.05 versus HG control) but at high doses, significantly attenuated IF exacerbation (23.2 ± 5.2% or 33.9 ± 3.6%, P < 0.05 versus HG control). However, the low-dose CF-TCEP conjugate significantly reduced IF (39.1 ± 1.7%, P < 0.05 versus HG control). IF was decreased to near euglycemic control levels (P > 0.05)., Conclusions: The CF-TECP conjugate synergistically attenuated HG infarct exacerbation at significantly lower respective doses of CF and TCEP. In addition to the intrinsic anti-inflammatory effect of blocking FPR1, CF is also a feasible tool for leukocyte-targeted therapy to treat IRI., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Ethnopharmacological Relevance: Positive evidence from clinical trials highlights the promising potential of traditional Chinese medication, Qili qiangxin capsule (QLQX), on chronic heart failure; however, limited data are available regarding its effects and mechanism in myocardial ischemia-reperfusion injury (MIRI). Herein, we aimed to explore cardioprotective effects and the underlying mechanism of QLQX in MIRI in vivo and in vitro., Materials and Methods: Mice were subjected to left anterior descending coronary artery ligation for 30 min followed by 24 h of reperfusion with or without 7-day pretreatment with QLQX (0.234, 0.468, or 0.936 g/kg). Cardiac function, myocardial infarction, and morphological changes were evaluated. The mechanism underlying the cardio-protection of QLQX on MIRI was determined by network pharmacology based on the common genes of potential targets of QLQX and MIRI-related genes, further validated by H9c2 cardiomyocytes exposing hypoxia/reoxygenation (H/R). The viability, apoptosis, as well as autophagy and relevant signaling proteins in H9c2 were analyzed., Results: QLQX pretreatment markedly improved cardiac function and decreased myocardium infarct size, apoptotic cardiomyocyte number, and LHD, CK-MB, and TnT levels in MIRI mice. QLQX could mitigate H/R-induced H9c2 cardiomyocyte injury, as evidenced by decreased cell apoptosis and LDH release and increased ATP production. QLQX effectively attenuates excessive autophagy in cardiomyocytes both in vivo and in vitro. Mechanically, network pharmacology analysis demonstrated the cardio-protection of QLQX on MIRI involving in PI3K/Akt signaling; the effects of QLQX on H/R-induced H9c2 cardiomyocytes were abolished by a specific PI3K inhibitor., Conclusion: QLQX protects against cardiomyocyte apoptosis and excessive autophagy via PI3K/Akt signaling during MIRI., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024 Elsevier B.V. All rights reserved.)

Ethnopharmacological Relevance: Dehydrocorydaline (DHC), an active component of Corydalis yanhusuo (Y.H. Chou & Chun C. Hsu) W.T. Wang ex Z.Y. Su & C.Y. Wu (Papaveraceae), exhibits protective and pain-relieving effects on coronary heart disease, but the underlying mechanism still remains unknown., Aim of the Study: Network pharmacology and experimental validation both in vivo and in vitro were applied to assess whether DHC can treat myocardial ischemia-reperfusion injury (MIRI) by regulating the forkhead box O (FoxO) signalling pathway to inhibit apoptosis., Materials and Methods: DHC and MIRI targets were retrieved from various databases. Molecular docking and microscale thermophoresis (MST) determined potential binding affinity. An in vivo mouse model of MIRI was established by ligating the left anterior descending coronary artery. C57BL/6N mice were divided into sham, MIRI, and DHC (intraperitoneal injection of 5 mg/kg DHC) groups. Haematoxylin and eosin, Masson, and immunohistochemical stainings verified DHC treatment effects and the involved signalling pathways. In vitro, H9c2 cells were incubated with DHC and underwent hypoxia/reoxygenation. TUNEL, JC-1, and reactive oxygen species stainings and western blots were used to explore the protective effects of DHC and the underlying mechanisms., Results: Venny analysis identified 120 common targets from 121 DHC and 23,354 MIRI targets. DHC exhibited high affinity for CCND1, CDK2, and MDM2 (<-7 kcal/mol). In vivo, DHC attenuated decreases in left ventricular ejection fraction and fractional shortening, reduced infarct sizes, and decreased cTnI and lactate dehydrogenase levels. In vitro, DHC alleviated apoptosis and oxidative stress in the hypoxia/reoxygenation model by attenuating ΔΨm disruption; reducing the production of reactive oxygen species; upregulating Bax and CCND1 via the FoxO signalling pathway, as well as cleaved-caspase 8; downregulating the apoptosis-associated proteins Bcl-2, Bid, cleaved-caspase 3, and cleaved-caspase 9; and promoting the phosphorylation of FOXO1A and MDM2., Conclusion: By upregulating the FoxO signaling pathway to inhibit apoptosis, DHC exerts a cardioprotective effect, which could serve as a potential therapeutic option for MIRI., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Citrus grandis fruit is a famous traditional Chinese medicine with various bioactivities, including cardioprotective effects. Polysaccharides are one of the key active ingredients responsible for its cardioprotective effects. This study aimed to investigate the structure and cardioprotective effect of a homogeneous polysaccharide from C. grandis fruit (CGP80-1) and explore its mechanism against myocardial ischemia-reperfusion (MI/R) injury. Structure analysis showed that CGP80-1 (11,917 Da) is an arabinan with compact coil chain conformation, containing →5)-α-L-Araf-(1→, →3,5)-α-L-Araf-(1→, and →2,3,5)-α-L-Araf-(1→ as the backbone, as well as →5)-α-L-Araf-(1→ and t-α-L-Araf as side-chains substituted at the C2 and C3 positions. Pharmacological experiments showed that pre-treatment with CGP80-1 could effectively alleviate MI/R injury by improving endogenous antioxidant enzymes and cardiac enzymes, reducing reactive oxygen species levels, and regulating apoptosis-related proteins such as caspase-3, Bax, and Bcl-2. The protective effects were correlated with the Nrf2/Keap1 and IRE1/GRP78 signaling pathways. Further analysis of structure-activity relationships revealed that the myocardial protection effects of CGP80-1 might be attributed to its appropriate molecular weight, high arabinose content, and unique compact coil chain conformation. Overall, our results provide insight into the chemical structure of CGP80-1 and its mechanism of action, suggesting that CGP80-1 could be a candidate drug for myocardial protection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Myocardial ischemia-reperfusion injury (MIRI) is a complex pathological process that results from the restoration of blood flow to ischemic myocardium, leading to a series of detrimental effects including oxidative stress and inflammation. Stachyose, a naturally occurring oligosaccharide found in traditional Chinese medicinal herbs, has been suggested to possess therapeutic properties against various pathological conditions. However, its impact on MIRI and the underlying mechanisms have not been fully elucidated. In this study, we aimed to investigate the therapeutic effects of stachyose on MIRI and to uncover the molecular mechanisms involved. Using both in vivo and in vitro models of MIRI, we evaluated the effects of stachyose on cardiac function and cell death pathways. Our results indicate that stachyose significantly improves cardiac function and reduces infarct size in MIRI mice. Mechanistically, stachyose modulates the ferroptotic pathway in cardiomyocytes by upregulating the expression of glutathione peroxidase 4 (GPX4) and reducing lipid peroxides and iron levels. Additionally, stachyose inhibits the pyroptotic pathway in macrophages by downregulating the expression of NLRP3, gasdermin D (GSMD-N), and cleaved-caspase-1, leading to decreased levels of proinflammatory cytokines interleukin (IL)-1β and IL-18. This study demonstrates that stachyose exerts a protective effect against MIRI by targeting both ferroptosis and pyroptosis pathways, suggesting its potential as a novel therapeutic agent for the treatment of MIRI. Further research is warranted to explore the detailed mechanisms and therapeutic potential of stachyose in clinical settings., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Hydroxyl Safflower Yellow A (HSYA) is the primary bioactive compound derived from Safflower, which has been scientifically proven to possess anti-inflammatory, anti-apoptotic, and ameliorative properties against mitochondrial damage during acute myocardial ischemia-reperfusion injury (MIRI); however, its effects during the recovery stage remain unknown. Angiogenesis plays a crucial role in the rehabilitation process., Aim of the Study: The objective of this study was to investigate the long-term angiogenic effect of HSYA and its contribution to recovery after myocardial ischemia, as well as explore its underlying mechanism using non-targeted metabolomics and network pharmacology., Materials and Methods: The MIRI model in rat was established by ligating the left anterior descending branch of the coronary artery. The effect of HSYA was assessed based on myocardial infarction volume and histopathology. Immunofluorescence staining was employed to evaluate angiogenesis, while ELISA was used to detect markers of myocardial injury. Additionally, a rat myocardial microvascular endothelial cell (CMECs) injury model was established using oxygen-glucose deprivation/reoxygenation (OGD/R), followed by scratch assays, migration assays, and tube formation experiments to assess angiogenesis. Western blot analysis was conducted to validate the underlying mechanism., Results: Our findings provide compelling evidence for the therapeutic efficacy of HSYA in reducing myocardial infarction size, facilitating cardiac functional recovery, and reversing pathological alterations within the heart. Furthermore, we elucidate that HSYA exerts its effects on promoting migration and generation of myocardial microvascular endothelial cells through activation of the HIF-1α-VEGFA-Notch1 signaling pathway., Conclusion: These results underscore how HSYA enhances cardiac function via angiogenesis promotion and activation of the aforementioned signaling cascade., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Objective: The aim of this study was to clarify whether Protein kinase B (PKB)/AKT is nitrated in myocardial ischemia and reperfusion injury (MIRI) resveratrol (RSV)'s protective effect during this process., Methods: We blocked blood flow of the left coronary artery (LAD) of mice and used H9c2 cells under an oxygen-glucose deprivation (OGD) environment as animal and cell models of MIRI. N-methyl-D-aspartic acid receptor (NMDAR) inhibitor MK801, neuronal nitric oxide synthase (nNOS) inhibitor 7-NI and RSV were used as interventions. Nitration of proteins, infarction area, cardiomyocyte apoptosis and AKT nitration sites were detected during this study., Results: During in-vivo study, AKT nitration was induced through the NMDAR/nNOS/peroxynitrite (ONOO - ) pathway, leading to decreased phosphorylation of AKT and increased cardiomyocyte apoptosis. AKT nitration was decreased and phosphorylation was elevated when administrated with RSV, MK801 and 7-NI. In in-vitro study, AKT nitration and TUNEL positive cells was elevated when administrated with NO donor H9c2 cells after OGD/R, when administrated with RSV, MK801 and 7-NI, AKT nitration and apoptosis was deceased in H9c2 cells. Mass spectrometry revealed that nitration sites of AKT included 14 Tyrosine residues., Discussion: RSV could inhibit AKT nitration and elevated phosphorylation through suppressing NMDAR/nNOS/ONOO - pathway and further reduce the apoptosis of cardiomyocytes in of myocardial I/R.

Gut microflora plays an important role in relieving myocardial no-reflow (NR), formononetin (FMN) has potential effects on NR, however, the relationship between this effect and gut microflora remains unclear. This study aimed to evaluate the role of FMN in alleviating NR by regulating gut microflora. We used a myocardial NR rat model to confirm the effect and mechanism of action of FMN in alleviating NR. The rats were randomly divided into sham operation group (Sham), NR group, FMN group and sodium nitroprusside (SNP) group. Thioflavin S staining, Hematoxylin Eosin (HE), myocardial enzyme activity, ultrasonic cardiogram and RT-PCR detection showed that FMN could effectively reduce inflammatory cell infiltration, NR and ischemic area, improve cardiac structure and function and reduce TNF-α and NF-κB gene expression in NR rats. The results of 16S rRNA high-throughput sequencing showed that FMN could increase the abundance of anti-inflammatory bacteria such as Ligilactobacillus, Coprococcus, Blautia and Muribaculaceae and decrease the abundance of pro-inflammatory bacteria such as Treponema in Spirochaetota and Campylobacterota. The correlation between the differential bacteria in the gut microflora(anti-inflammatory bacteria and pro-inflammatory bacteria) and TNF-α and NF-κB, showed that they had a strong correlation. Therefore, the anti-NR mechanism of FMN may be related to increasing the abundance of anti-inflammatory bacteria and reducing the abundance of pro-inflammatory bacteria to inhibit inflammation. This study provides innovative mechanistic insights into the relationship between gut microbiota and myocardial protection, suggesting potential strategy for future treatment of NR., Competing Interests: Declaration of competing interest The authors declare that no conflicts of interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The early restoration of hemodynamics/reperfusion in acute myocardial infarction (AMI) is an effective therapeutic strategy to reduce sudden death and improve patient prognosis. However, reperfusion induces additional cardiomyocyte damage and cardiac tissue dysfunction. In this context, turmeric‑derived curcumin (Cur) has been shown to exhibit a protective effect against myocardial ischemia/reperfusion injury (I/RI). The molecular mechanism of its activity, however, remains unclear. The current study investigated the protective effect of Cur and its molecular mechanism via in vitro experiments. The Cell Counting Kit‑8 and lactate dehydrogenase (LDH) assay kit were used to assess the cell viability and cytotoxicity. The contents of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase, glutathione (GSH)/glutathione disulfide (GSSG), total iron, ferrous iron, caspase‑3 and reactive oxygen species (ROS) were measured using an appropriate kit. Western blotting was used to detect the expression of relevant proteins. The levels of apoptosis, mitochondrial permeability transition pore (MPTP) opening, and mitochondrial membrane potential (MMP) were detected by flow cytometry. The study findings indicated that anoxia/reoxygenation (A/R) injury significantly decreased cell viability, increased in LDH and caspase‑3 activities, induced ferroptosis, increased apoptosis and overactivated autophagy. However, pretreatment with Cur or ferrostatin‑1 (Fer‑1, a ferroptosis inhibitor) significantly increased A/R‑reduced cell viability, SOD, glutathione peroxidase activity, GSH/GSSH ratio and HES1 and glutathione peroxidase 4 protein expression; attenuated A/R‑induced LDH, MDA, total iron, ferrous iron, prostaglandin‑endoperoxide synthase 2 protein expression and prevented ROS overproduction and MMP loss. In addition, Cur inhibited caspase‑3 activity, upregulated the Bcl‑2/Bax ratio, reduced apoptotic cell number and inhibited MPTP over‑opening. Furthermore, Cur increased P62, LC3II/I, NDUFB8 and UQCRC2 expression and upregulated the p‑AMPK/AMPK ratio. However, erastin (a ferroptosis activator), pAD/HES1‑short hairpin RNA, rapamycin (an autophagy activator) and Compound C (an AMPK inhibitor) blocked the protective effect of Cur. In conclusion, Cur pretreatment inhibited ferroptosis, autophagy overactivation and oxidative stress; improved mitochondrial dysfunction; maintained energy homeostasis; attenuated apoptosis; and ultimately protected the myocardium from A/R injury via increased HES1 expression.

The present study aimed to investigate the role of PI3K‑mediated ferroptosis signaling induced by mild therapeutic hypothermia (MTH), which was defined as a temperature of 34˚C, in protecting against myocardial ischemia-reperfusion (I/R) injury (MIRI). To meet this aim, H9C2 cells underwent hypoxia‑reperfusion (H/R) and/or MTH. The MTT assay was used to assess cell viability, cytotoxicity was measured using a lactate dehydrogenase cytotoxicity assay, and Annexin V‑FITC/PI flow cytometric analysis was used to analyze early and late cell apoptosis. In addition, 84 healthy adult male Sprague‑Dawley rats were randomly divided into seven groups (n=12), and underwent I/R and various treatments. Hemodynamics were monitored, and the levels of myocardial injury marker enzymes and oxidative stress markers in myocardial tissue were measured using ELISA. The expression levels of PI3K, AKT, transient receptor potential cation channel subfamily M member 7 (TRPM7), glutathione peroxidase 4 (GPX4) and acyl‑CoA synthetase long chain family member 4 (ACSL4) in animals and cells were measured using western blot analysis. These experiments revealed that MTH could effectively reduce myocardial infarct size, improve hemodynamic performance following MIRI and suppress myocardial apoptosis, thereby contributing to the recovery from H/R injury. Mechanistically, MTH was revealed to be able to activate the PI3K/AKT signaling pathway in cells, upregulating GPX4, and downregulating the expression levels of TRPM7 and ACSL4. Treatment with 2‑aminoethoxydiphenyl borate (an inhibitor of TRPM7) could further strengthen the myocardial protective effects of MTH, whereas treatment with erastin (promoter of ferroptosis) and wortmannin (inhibitor of PI3K) led to the effective elimination of the myocardial protective effects of MTH. Compared with in the I/R group, the PI3K/AKT activation level and the expression levels of GPX4 were both significantly increased, whereas the expression levels of TRPM7 and ACSL4 were significantly decreased in the I/R + MTH group. Taken together, the results of the present study indicated that MTH may activate the PI3K/AKT signaling pathway to inhibit TRPM7 and suppress ferroptosis induced by MIRI.

Background and Purpose: Adenosine receptor activation induces delayed, sustained cardioprotection against ischaemia-reperfusion (IR) injury (24-72 h), but the mechanisms underlying extended cardioprotection duration remain unresolved. We hypothesized that a positive feedback loop involving adenosine receptor-induced proteasomal degradation of adenosine kinase (ADK) and decreased myocardial adenosine metabolism extends the duration of cardioprotection., Experimental Approach: Mice were administered an ADK inhibitor, ABT-702, to induce endogenous adenosine signalling. Cardiac ADK protein and mRNA levels were analysed 24-120 h later. Theophylline or bortezomib was administered 24 h after ABT-702 to examine the late roles of adenosine receptors or proteasomal activity, respectively, in ADK expression and cardioprotection at 72 h. Coronary flow and IR tolerance were analysed by Langendorff technique. The potential for continuous adenosinergic cardioprotection was examined using heterozygous, cardiac-specific ADK KO (cADK +/- ) mice. Cardiac ADK expression was also examined after A 1 or A 3 receptor agonist, phenylephrine, lipopolysaccharide or sildenafil administration., Key Results: ABT-702 treatment decreased ADK protein content and provided cardioprotection from 24 to 72 h. ADK mRNA upregulation restored ADK protein after 96-120 h. Adenosine receptor or proteasome inhibition at 24 h reversed ABT-702-induced ADK protein deficit and cardioprotection at 72 h. cADK +/- hearts exhibited continuous cardioprotection. Diverse preconditioning agents also diminished cardiac ADK protein expression., Conclusion and Implications: A positive feedback loop driven by adenosine receptor-induced ADK degradation and renewed adenosine signalling extends the duration of cardioprotection by ABT-702 and possibly other preconditioning agents. The therapeutic potential of continuous adenosinergic cardioprotection is demonstrated in cADK +/- hearts., (© 2024 The Author(s). British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)

Objective: This study aimed to investigate the mechanism of emulsified isoflurane in reducing myocardial ischemia-reperfusion injury (MIRI)., Materials and Methods: Forty-eight healthy male Sprague-Dawley rats were randomly divided into four groups ( n  = 12). In the sham group (group S) and ischemia-reperfusion group (group I/R), saline (4 ml/kg/h) was administered intravenously for 30 min. In intralipid group (group L), intralipid (4 ml/kg/h) was administered intravenously. In the emulsified isoflurane group (group EI), emulsified isoflurane (4 ml/kg/h) was administered intravenously. The infusion was then discontinued for 15 min during the washout period. Apart from group S, ischemia was produced by occlusion of the left anterior descending artery (LADA) for 30 min. After 30 min of occlusion, all groups received reperfusion for two hours., Results: Creatine kinase MB (CK-MB), cardiac troponin I (cTnI), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) were measured by enzyme-linked immunosorbent assay (ELISA). Myocardial infarct size was measured using triphenyl tetrazolium chloride staining. According to the result, pretreatment with emulsified isoflurane attenuated CK-MB and cTnI concentrations ( p  < 0.05). And serum TNF-α and IL-6 levels and infarct size in the emulsified isoflurane group obviously decreased. An obvious decrease in the expression of the toll-like receptor-4 (TLR-4) mRNA in group EI was observed compared with group I/R., Discussion and Conclusion: Emulsified isoflurane precondition had a potent cardioprotective effect against myocardial ischemia-reperfusion injury. The mechanisms involved may be related to the decrease in the expression of TLR-4 and the reduced inflammatory response.

Acute myocardial infarction, characterized by high morbidity and mortality, has now become a serious health hazard for human beings. Conventional surgical interventions to restore blood flow can rapidly relieve acute myocardial ischemia, but the ensuing myocardial ischemia-reperfusion injury (MI/RI) and subsequent heart failure have become medical challenges that researchers have been trying to overcome. The pathogenesis of MI/RI involves several mechanisms, including overproduction of reactive oxygen species, abnormal mitochondrial function, calcium overload, and other factors that induce cell death and inflammatory responses. These mechanisms have led to the exploration of antioxidant and inflammation-modulating therapies, as well as the development of myocardial protective factors and stem cell therapies. However, the short half-life, low bioavailability, and lack of targeting of these drugs that modulate these pathological mechanisms, combined with liver and spleen sequestration and continuous washout of blood flow from myocardial sites, severely compromise the expected efficacy of clinical drugs. To address these issues, employing conventional nanocarriers and integrating them with contemporary biomimetic nanocarriers, which rely on passive targeting and active targeting through precise modifications, can effectively prolong the duration of therapeutic agents within the body, enhance their bioavailability, and augment their retention at the injured myocardium. Consequently, these approaches significantly enhance therapeutic effectiveness while minimizing toxic side effects. This article reviews current drug delivery systems used for MI/RI, aiming to offer a fresh perspective on treating this disease.

Background: Microvascular dysfunction (MVD) is common in patients with myocardial infarction receiving reperfusion therapy and is associated with adverse cardiac prognosis. Accumulating evidence suggests a protective role of Shexiang Tongxin dropping pill (STDP) in MVD. However, the specific effects and the underlying mechanisms of STDP in the context of MVD after myocardial ischemia-reperfusion (IR) remains unclear., Aims: We aimed to elucidate the role of STDP in MVD induced by IR and the potential mechanisms involved., Methods: Mice were orally administered with STDP or normal saline for 5 days before receiving myocardial IR. Cardiac function and microvascular obstruction was measured. Proteomics and single-cell RNA sequencing was performed on mouse hearts. In vitro hyoxia/reoxygenation model was established on mouse cardiac microvascular endothelial cells (MCMECs)., Results: STDP improved cardiac function and decreased microvascular obstruction (MVO) in mice after myocardial IR. Proteomics identified ALOX12 as an important target of STDP. Single-cell RNA sequencing further revealed that downregulation of ALOX12 by STDP mainly occurred in endothelial cells. The involvement of ALOX12 in the effect of STDP on MVO was validated by manipulating ALOX12 via endothelial-specific adeno-associated virus transfection in vivo and in vitro. In vivo, overexpression of ALOX12 increased whereas knockdown of ALOX12 decreased MVO and thrombus formation. STDP treatment alleviated the detrimental effects of overexpression of ALOX12. In vitro, overexpression of ALOX12 increased endothelial cell inflammation and platelet adhesion to endothelial cells, which was abolished by STDP treatment., Conclusion: Our findings suggest that STDP alleviates MVO after IR, with ALOX12 playing a crucial role., Competing Interests: Declaration of competing interest On behalf of all authors, the corresponding author states that there is no conflict of interest and all authors agree to submit the manuscript to your journal., (Copyright © 2024 Elsevier B.V. All rights reserved.)

While 3-N-butylphthalide (NBP) has demonstrated notable cardioprotective effects, its precise role in mitigating myocardial arrhythmia following ischemia/reperfusion (IR) injury in diabetes remains unclear. This study aimed to explore the potential mechanisms through which NBP mitigates reperfusion-induced myocardial arrhythmia in diabetic rats, with a particular focus on mitochondrial function and biogenesis, endoplasmic reticulum (ER) stress, and oxidative/inflammatory responses. Sixty Sprague-Dawley rats were divided into non-diabetic and diabetic groups, subjected to in-vivo myocardial IR injury, and treated with NBP (100 mg/kg, intraperitoneally) through different modalities: preconditioning, postconditioning, or a combination of both. Electrocardiography (ECG) was employed to assess the incidence and severity of arrhythmia. Fluorometric, Western blotting and ELISA analyses were utilized to measure the mitochondrial, ER stress, and cellular outcomes. Treatment of non-diabetic rats with NBP in preconditioned, postconditioned, and combined approaches significantly reduced cardiotroponin-I and the frequency and severity of arrhythmias induced by IR injury. However, only the combined preconditioning plus postconditioning approach of NBP had protective and antiarrhythmic effects in diabetic rats, in an additive manner. Moreover, the NBP combined approach improved mitochondrial function and upregulated the expression of PGC-1?, Sirt1, and glutathione while concurrently downregulating ER stress and oxidative and pro-inflammatory-related proteins in diabetic rats. In conclusion, the combined approach of NBP treatment was effective in mitigating myocardial arrhythmia in diabetic rats. This approach coordinates interactions within the mitochondria-endoplasmic reticulum network and inhibits oxidative and inflammatory mediators, offering a promising strategy for managing myocardial arrhythmia in diabetic patients. Key words: Myocardial Infarction, Mitochondria, Arrhythmia, Reperfusion, Diabetes, Ischemia.

Myocardial ischaemia reperfusion injury (IRI) occurring from acute coronary artery disease or cardiac surgical interventions such as bypass surgery can result in myocardial dysfunction, presenting as, myocardial "stunning", arrhythmias, infarction, and adverse cardiac remodelling, and may lead to both a systemic and a localised inflammatory response. This localised cardiac inflammatory response is regulated through the nucleotide-binding oligomerisation domain (NACHT), leucine-rich repeat (LRR)-containing protein family pyrin domain (PYD)-3 (NLRP3) inflammasome, a multimeric structure whose components are present within both cardiomyocytes and in cardiac fibroblasts. The NLRP3 inflammasome is activated via numerous danger signals produced by IRI and is central to the resultant innate immune response. Inhibition of this inherent inflammatory response has been shown to protect the myocardium and stop the occurrence of the systemic inflammatory response syndrome following the re-establishment of cardiac circulation. Therapies to prevent NLRP3 inflammasome formation in the clinic are currently lacking, and therefore, new pharmacotherapies are required. This review will highlight the role of the NLRP3 inflammasome within the myocardium during IRI and will examine the therapeutic value of inflammasome inhibition with particular attention to carbon monoxide, nitric oxide, and hydrogen sulphide as potential pharmacological inhibitors of NLRP3 inflammasome activation.