Molecular machinery and interplay of apoptosis and autophagy in coronary heart disease

BECN1 regulates FADD/RIPK1/Caspase-8 complex formation via RIPK1 ubiquitination by downregulating OTUD1 in MI/R induced myocyte apoptosis

BACKGROUND

Cardiomyocyte apoptosis plays a vital role in myocardial ischemia-reperfusion (MI/R) injury; however, the role of beclin1 (BECN1) remains unclear. This study aimed at revealing the function of BECN1 during cardiomyocyte apoptosis after MI/R injury.

METHODS

In vivo, TTC and Evan's blue double staining was applied to verify the gross morphological alteration in both wild type (WT) mice and BECN1 transgene mice (BECN1-TG), and TUNEL staining and western blot were adopted to evaluate the cardiomyocyte apoptosis. In vitro, a hypoxia/reoxygenation (H/R) model was established in H9c2 cells to simulate MI/R injury. Proteomics analysis was preformed to verify if apoptosis occurs in the H/R cellular model. And apoptosis factors, RIPK1, Caspase-1, Caspase-3, and cleaved Caspase-3, were investigated using western bolting. In addition, the mRNA level were verified using RT-PCR. To further investigate the protein interactions small interfering RNA and lentiviral transfection were used. To continue investigate the protein interactions, immunofluorescence and coimmunoprecipitation were applied.

RESULTS

Morphologically, BECN1 significantly attenuated the apoptosis from TTC-Evan's staining, TUNEL, and cardiac tissue western blot. After H/R, a RIPK1-induced complex (complex II) containing RIPK1, Caspase-8, and FADD was formed. Thereafter, cleaved Caspase-3 was activated, and myocyte apoptosis occurred. However, BECN1 decreased the expression of RIPK1, Caspase-8, and FADD. Nevertheless, BECN1 overexpression increased RIPK1 ubiquitination before apoptosis by inhibiting OTUD1.

CONCLUSIONS

BECN1 regulates FADD/RIPK1/Caspase-8 complex formation via RIPK1 ubiquitination by downregulating OTUD1 in C-Caspase-3-induced myocyte apoptosis after MI/R injury. Therefore, BECN1 can function as a cardioprotective candidate.

Network pharmacology analysis and experimental verification of the antithrombotic active compounds of trichosanthis pericarpium (Gualoupi) in treating coronary heart disease

ETHNOPHARMACOLOGICAL RELEVANCE

Trichosanthis pericarpium (TP; Gualoupi, pericarps of Trichosanthes kirilowii Maxim) has been used in traditional Chinese medicine (TCM) to reduce heat, resolve phlegm, promote Qi, and clear chest congestion. It is also an essential herbal ingredient in the "Gualou Xiebai" formula first recorded by Zhang Zhongjing (from the Eastern Han Dynasty) in the famous TCM classic "Jin-Guì-Yào-Lüe" for treating chest impediments. According to its traditional description, Gualou Xiebai is indicated for symptoms of chest impediments, which correspond to coronary heart diseases (CHD).

AIM OF THE STUDY

This study aimed to identify the antithrombotic compounds in Gualoupi for the treatment of CHD.

MATERIALS AND METHODS

A CHD rat model was established with a combination of high-fat diet and isoproterenol hydrochloride (ISO) administration via subcutaneous multi-point injection in the back of the neck. This model was used to evaluate the antithrombotic effect of two mainstream cultivars of TP ("HaiShi GuaLou" and "WanLou") by analyzing the main components and their effects. Network pharmacology, molecular docking-based studies, and a zebrafish (Danio rerio) thrombosis model induced by phenylhydrazine was used to validate the antithrombosis components of TP.

RESULTS

TP significantly reduced the body weight of the CHD rats, improved myocardial ischemia, and reduced collagen deposition and fibrosis around the infarcted tissue. It reduced thrombosis in a dose-dependent manner and significantly reduced inflammation and oxidative stress damage. Cynaroside, isoquercitrin, rutin, citrulline, and arginine were identified as candidate active TP compounds with antithrombotic effects. The key potential targets of TP in thrombosis treatment were initially identified by molecular docking-based analysis, which showed that the candidate active compounds have a strong binding affinity to the potential targets (protein kinase C alpha type [PKCα], protein kinase C beta type [PKCβ], von Willebrand factor [vWF], and prostaglandin-endoperoxide synthase 1 [PTGS1], fibrinogen alpha [Fga], fibrinogen beta [Fgb], fibrinogen gamma [Fgg], coagulation factor II [F2], and coagulation factor VII [F7]). In addition, the candidate active compounds reduced thrombosis, improved oxidative stress damage, and down-regulated the expression of thrombosis-related genes (PKCα, PKCβ, vWF, PTGS1, Fga, Fgb, Fgg, F2, and F7) in the zebrafish model.

CONCLUSION

Cynaroside, isoquercitrin, rutin, citrulline, and arginine were identified as the active antithrombotic compounds of TP used to treat CHD. Mechanistically, the active compounds were found to be involved in oxidative stress injury, platelet activation pathway, and complement and coagulation cascade pathways.

The role of hydrogen in the prevention and treatment of coronary atherosclerotic heart disease

Coronary atherosclerotic heart disease (CHD) is a primary cardiovascular disease caused by atherosclerosis (AS), which is characterized by chronic inflammation and lipid oxidative deposition. Molecular hydrogen (H2) is an effective anti-inflammatory agent and has potential to ameliorate glycolipid metabolism disorders, which is believed to exert beneficial effects on the prevention and treatment of CHD. It is suggested that H2 reduces inflammation in CHD by regulating multiple pathways, including NF-κB inflammatory pathway, pyroptosis, mitophagy, endoplasmic reticulum (ER) stress, and Nrf2 antioxidant pathway. Additionally, H2 may improve glycolipid metabolism by mediation of PI3K and AMPK signalling pathways, contributing to inhibition of the occurrence and development of CHD. This review elaborates pathogenesis of CHD and evaluates the role of H2 in CHD. Moreover, possible molecular mechanisms have been discussed and speculated, aiming to provide more strategies and directions for subsequent studies of H2 in CHD.

Emodin alleviates intestinal ischemia/reperfusion-induced lung injury by upregulating HO-1 expression via PI3K/AkT pathway

BACKGROUND

Emodin, a natural anthraquinone derivative found in various Chinese medicinal herbs, has been proved to be an effective therapeutic agent in the treatment of many diseases. However, its effect on lung injury after intestinal ischemia/reperfusion injury remains unknown. This research was designed to investigate whether emodin protects against intestinal ischemia/reperfusion-induced lung injury and to elucidate the underlying molecular mechanisms in vivo and in vitro.

METHODS

Intestinal ischemia/reperfusion injury was induced by occluding the superior mesenteric artery in mice, and mouse lung epithelial-12 cells were subjected to oxygen-glucose deprivation and reoxygenation to establish an in vitro model.

RESULTS

Our data indicated that emodin treatment reduced intestinal ischemia/reperfusion-induced oxidative stress, inflammation and apoptosis in lung tissues and alleviated lung injury. However, the protective effects of emodin on intestinal ischemia/reperfusion-induced lung injury were reversed by the protein kinase B inhibitor triciribine or the heme oxygenase-1 inhibitor tin protoporphyrin IX. The protein kinase inhibitor triciribine also downregulated the expression of heme oxygenase-1.

CONCLUSION

In conclusion, our data suggest that emodin treatment protects against intestinal ischemia/reperfusion-induced lung injury by enhancing heme oxygenase-1 expression via activation of the PI3K/protein kinase pathway. Emodin may act as a potential therapeutic agent for the prevention and treatment of lung injury induced by intestinal ischemia/reperfusion.

Salvianolic acid A alleviates H2O2-induced endothelial oxidative injury via miR-204-5p

Oxidative stress induced endothelial dysfunction plays a particularly important role in promoting the development of cardiovascular diseases (CVDs). Salvianolic acid A (SalA) is a water-soluble component of traditional Chinese medicine Salvia miltiorrhiza Bunge with anti-oxidant potency. This study aims to explore the regulatory effect of SalA on oxidative injury using an in vitro model of H2O2-induced injury in human umbilical vein endothelial cells (HUVECs). In the study, we determined cell viability, the activities of Lactate dehydrogenase (LDH) and Superoxide dismutase (SOD), cell proliferation rate and intracellular reactive oxygen species (ROS). Flow cytometry was used to detect cell apoptosis. Western-blotting was used to evaluate the expression of cell senescence, apoptosis, autophagy and pyroptosis protein factors. The expression level of miRNA was determined by qRT-PCR. Compared with H2O2-induced HUVECs, SalA promoted cell viability and cell proliferation rate; decreased LDH and ROS levels; and increased SOD activity. SalA also significantly attenuated endothelial senescence, inhibited cell apoptosis, reversed the increase of LC3 II/I ratio and NLRP3 accumulation. Furthermore, miR-204-5p was regulated by SalA. Importantly, miR-204-5p inhibitor had similar effect to that of SalA on H2O2-induced HUVECs. Our results indicated that SalA could alleviate H2O2-induced oxidative injury by downregulating miR-204-5p in HUVECs.

The activation of LBH-CRYAB signaling promotes cardiac protection against I/R injury by inhibiting apoptosis and ferroptosis

Myocardial ischemia-reperfusion (I/R) injury stands out among cardiovascular diseases, and current treatments are considered unsatisfactory. For cardiomyocytes (CMs) in ischemic tissues, the upregulation of Limb-bud and Heart (LBH) and αB-crystallin (CRYAB) and their subsequent downregulation in the context of cardiac fibrosis have been verified in our previous research. Here, we focused on the effects and mechanisms of activated LBH-CRYAB signaling on damaged CMs during I/R injury, and confirmed the occurrence of mitochondrial apoptosis and ferroptosis during I/R injury. The application of inhibitors, ectopic expression vectors, and knockout mouse models uniformly verified the role of LBH in alleviating both apoptosis and ferroptosis of CMs. p53 was identified as a mutual downstream effector for both LBH-CRYAB-modulated apoptosis and ferroptosis inhibition. In mouse models, LBH overexpression was confirmed to exert enhanced cardiac protection against I/R-induced apoptosis and ferroptosis, suggesting that LBH could serve as a promising target for the development of I/R therapy.

Exploring the Mechanism of Fufang Danshen Tablet against Atherosclerosis by Network Pharmacology and Experimental Validation

Atherosclerosis is the main pathological basis of cardiovascular diseases (CVDs). Fufang Danshen Tablet (FDT) is a traditional Chinese medicine that has been clinically used to treat CVDs for more than 40 years. Nevertheless, owing to the complexity of the ingredients, the pharmacological mechanism of FDT in the treatment of CVDs has not been fully elucidated. In this study, an integrated strategy of UFLC-Q-TOF-MS/MS, network pharmacology, molecular biology, and transcriptomics was used to elucidate the mechanisms of action of FDT in the treatment of atherosclerosis. In total, 22 absorbed constituents were identified in rat serum after oral administration of FDT. In silico, network pharmacology studies have shown that FDT regulates four key biological functional modules for the treatment of atherosclerosis: oxidative stress, cell apoptosis, energy metabolism, and immune/inflammation. In animal experiments, FDT exerted protective effects against atherosclerosis by reducing the plaque area and lipid levels in ApoE-/- mice. Furthermore, we found that FDT inhibited inflammatory macrophage accumulation by regulating the expression of Selp and Ccl2, which are both involved in monocyte adhesion and migration. The inhibition of monocyte recruitment by FDT is a new perspective to elucidate the anti-atherosclerotic mechanism of FDT, which has not been adopted in previous studies on FDT. Our results may help to elucidate the therapeutic mechanism of FDT against CVDs and provide potential therapeutic targets.

PCSK9 induces endothelial cell autophagy by regulating the PI3K/ATK pathway in atherosclerotic coronary heart disease

OBJECTIVE

Atherosclerosis is a chronic inflammatory disease of the arteries, and its pathogenesis is related to endothelial dysfunction. It has been found that the protein convertase subtilin/kexin9 type (PCSK9) plays an important role in AS, but its specific mechanism is still unclear.

METHODS

In this study, we first cultured human umbilical vein endothelial cells (HUVECs) with 50 or 100μg/ml oxidized low-density lipoprotein (ox-LDL) for 24 hours to establish a coronary atherosclerosis cell model.

RESULTS

The results showed that ox-LDL induced HUVEC injury and autophagy and upregulated PCSK9 protein expression in HUVECs in a concentration-dependent manner. Silencing PCSK9 expression with siRNA inhibited ox-LDL-induced HUVEC endothelial dysfunction, inhibited the release of inflammatory factors, promoted HUVEC proliferation and inhibited apoptosis. In addition, ox-LDL increased the expression of LC3B-I and LC3B-II and decreased the expression of p62. However, these processes are reversed by sh-PCSK9. In addition, sh-PCSK9 can inhibit PI3K, AKT and mTOR phosphorylation and promote autophagy.

CONCLUSION

Taken together, our research shows that silencing PCSK9 inhibits the PI3K/ATK/mTOR pathway to activate ox-LDL-induced autophagy in vascular endothelial cells, alleviating endothelial cell injury and inflammation.

Genetic diversity, clinical uses, and phytochemical and pharmacological properties of safflower (Carthamus tinctorius L.): an important medicinal plant

Safflower (Carthamus tinctorius L.), a member of the Asteraceae family, is widely used in traditional herbal medicine. This review summarized agronomic conditions, genetic diversity, clinical application, and phytochemicals and pharmacological properties of safflower. The genetic diversity of the plant is rich. Abundant in secondary metabolites like flavonoids, phenols, alkaloids, polysaccharides, fatty acids, polyacetylene, and other bioactive components, the medicinal plant is effective for treating cardiovascular diseases, neurodegenerative diseases, and respiratory diseases. Especially, Hydroxysafflor yellow A (HYSA) has a variety of pharmacological effects. In terms of treatment and prevention of some space sickness in space travel, safflower could be a potential therapeutic agent. Further studies are still required to support the development of safflower in medicine. Our review indicates that safflower is an important medicinal plant and research prospects regarding safflower are very broad and worthy of further investigation.

Quercetin Ameliorates Myocardial Injury in Diabetic Rats by Regulating Autophagy and Apoptosis through AMPK/mTOR Signaling Pathway

A high-glucose environment is involved in the progression of diabetes mellitus (DM). This study aims to explore the regulatory effects of quercetin (QUE) on autophagy and apoptosis after myocardial injury in rats with DM. The type 2 DM rat models were constructed using low-dose streptozotocin (STZ) treatment combined with a high-carbohydrate (HC) diet in vivo. Compared with the control group, the body weight was decreased, whereas blood pressure, blood glucose, and the LVW/BW ratio were increased in the diabetic group. The results showed that the myocardial fibers were disordered in the diabetic group. Moreover, we found that the myocardial collagen fibers, PAS-positive cells, and apoptosis were increased, whereas the mitochondrial structure was destroyed and autophagic vacuoles were significantly reduced in the diabetic group compared with the control group. The expression levels of autophagy-related proteins LC3 and Beclin1 were decreased, whereas the expression levels of P62, Caspae-3, and Bax/Bcl-2 were increased in the diabetic group in vitro and in vivo. Moreover, QUE treatment alleviated the cellular oxidative stress reaction under high-glucose environments. The results of immunoprecipitation (IP) showed that the autophagy protein Beclin1 was bound to Bcl-2, and the binding capacity increased in the HG group, whereas it decreased after QUE treatment, suggesting that QUE inhibited the binding capacity between Beclin1 and Bcl-2, thus leading to the preservation of Beclin1-induced autophagy. In addition, the blood pressure, blood glucose, and cardiac function of rats were improved following QUE treatment. In conclusion, QUE suppressed diabetic myocardial injury and ameliorated cardiac function by regulating myocardial autophagy and inhibition of apoptosis in diabetes through the AMPK/mTOR signaling pathway.

A bibliometric analysis of the application of the PI3K-AKT-mTOR signaling pathway in cancer

PI3K-AKT-mTOR plays as important role in the growth, metabolism, proliferation, and migration of cancer cells, and in apoptosis, autophagy, inflammation, and angiogenesis in cancer. In this study, the aim was to comprehensively review the current research landscape regarding the PI3K-AKT-mTOR pathway in cancer, using bibliometrics to analyze research hotspots, and provide ideas for future research directions. Literature published on the topic between January 2006 and May 2023 was retrieved from the Web of Science core database, and key information and a visualization map were analyzed using CiteSpace and VOSviewer. A total of 5800 articles from 95 countries/regions were collected, including from China and the USA. The number of publications on the topic increased year on year. The major research institution was the University of Texas MD Anderson Cancer Center. Oncotarget and Clinical Cancer Research were the most prevalent journals in the field. Of 26,621 authors, R Kurzrock published the most articles, and J Engelman was cited most frequently. "A549 cell," "first line treatment," "first in human phase I," and "inhibitor" were the keywords of emerging research hotspots. Inhibitors of the PI3K-AKT-mTOR pathway and their use in clinical therapeutic strategies for cancer were the main topics in the field, and future research should also focus on PI3K-AKT-mTOR pathway inhibitors. This study is the first to comprehensively summarize trends and development s in research into the PI3K-AKT-mTOR pathway in cancer. The information that was obtained clarified recent research frontiers and directions, providing references for scholars of cancer management.

Construction of preclinical evidence for propofol in the treatment of reperfusion injury after acute myocardial infarction: A systematic review and meta-analysis

Propofol, a commonly used intravenous anesthetic, has demonstrated potential in protecting against myocardial ischemia/reperfusion injury (MIRI) based on preclinical animal studies. However, the clinical benefits of propofol in this context are subject to debate. We conducted a systematic search across eight databases to identify all relevant animal studies investigating the preventive effects of propofol on MIRI until October 30, 2023. We assessed the methodological quality of the included studies using SYRCLE's bias risk tool. Statistical analysis was performed using STATA 15.1. The primary outcome measures analyzed in this study were myocardial infarct size (IS) and myocardial injury biomarkers. This study presents a comprehensive analysis of 48 relevant animal studies investigating propofol's preventive effects on MIRI. Propofol administration demonstrated a reduction in myocardial IS and decreased levels of myocardial injury biomarkers (CK-MB, LDH, cTnI). Moreover, propofol improved myocardial function parameters (+dp/dtmax, -dP/dtmax, LVEF, LVFS), exhibited favorable effects on inflammatory markers (IL-6, TNF-α) and oxidative stress markers (SOD, MDA), and reduced myocardial cell apoptotic index (AI). These findings suggest propofol exerts cardioprotective effects by reducing myocardial injury, decreasing infarct size, and improving heart function. However, the absence of animal models that accurately represent comorbidities such as aging and hypertension, as well as inconsistent administration methods that align with clinical practice, may hinder its clinical translation. Further robust investigations are required to validate these findings, elucidate the underlying mechanisms of propofol, and facilitate its potential translation into clinical practice.

Exploring the effective compounds and potential mechanisms of Shengxian Decoction against coronary heart disease by UPLC-Q-TOF/MS and network pharmacology analysis

As a well-known classical Chinese medicine prescription, Shengxian Decoction (SXD) has been applied for a century to treat cardiovascular diseases, especially coronary heart disease (CHD), but the potentially effective compounds and underlying mechanisms remain unclear. With ultra-performance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-Q-TOF/MS) and network pharmacology analysis, the potential effective compounds of SXD and their pharmacological mechanisms against CHD were identified and revealed. 57 effective compounds with favorable pharmacokinetic characteristics and biological activities were screened through UPLC-Q-TOF/MS analysis, database and literature mining, interacting with 96 CHD-related targets to support potential synergistic therapeutic actions. Systematic analysis of the PPI network and microarray data further revealed six core targets, including TNF, IL-1β, IL-6, TP53, VEGFA and PTGS2, which were mainly involved in fluid shear stress and atherosclerosis, lipid and atherosclerosis, PI3K-Akt signaling pathway et al. Moreover, the proposed contribution indexes of effective compounds indicated these compounds, including isoferulic acid, quercetin, calycosin, ferulic acid, kaempferol, calycosin 7-O-glycoside, formononetin, astragaloside IV and saikosaponin D, as the core compounds of SXD. The molecular docking results confirmed that those core compound-target pairs exhibited strong binding energy. Furthermore, we validated that SXD significantly alleviated myocardial tissue injury in CHD rats and reversed H/R-induced decreases in H9c2 cell viability by attenuating the production of TNF, IL-6 and IL-1β, and reducing cardiomyocyte apoptosis via down-regulating the TP53, caspase3 and cytochrome C mRNA expression levels as well as caspase3, caspase9 and cytochrome C protein expression levels according to RT-qPCR and Western blot results. Our findings explained the pharmacological mechanisms underlying the effectiveness of SXD in the treatment of CHD, and laid a foundation for future basic and clinical research of SXD.

Teneligliptin mitigates diabetic cardiomyopathy by inhibiting activation of the NLRP3 inflammasome

BACKGROUND

Diabetic cardiomyopathy (DCM), which is a complication of diabetes, poses a great threat to public health. Recent studies have confirmed the role of NLRP3 (NOD-like receptor protein 3) activation in DCM development through the inflammatory response. Teneligliptin is an oral hypoglycemic dipeptidyl peptidase-IV inhibitor used to treat diabetes. Teneligliptin has recently been reported to have anti-inflammatory and protective effects on myocardial cells.

AIM

To examine the therapeutic effects of teneligliptin on DCM in diabetic mice.

METHODS

Streptozotocin was administered to induce diabetes in mice, followed by treatment with 30 mg/kg teneligliptin.

RESULTS

Marked increases in cardiomyocyte area and cardiac hypertrophy indicator heart weight/tibia length reductions in fractional shortening, ejection fraction, and heart rate; increases in creatine kinase-MB (CK-MB), aspartate transaminase (AST), and lactate dehydrogenase (LDH) levels; and upregulated NADPH oxidase 4 were observed in diabetic mice, all of which were significantly reversed by teneligliptin. Moreover, NLRP3 inflammasome activation and increased release of interleukin-1β in diabetic mice were inhibited by teneligliptin. Primary mouse cardiomyocytes were treated with high glucose (30 mmol/L) with or without teneligliptin (2.5 or 5 µM) for 24 h. NLRP3 inflammasome activation. Increases in CK-MB, AST, and LDH levels in glucose-stimulated cardiomyocytes were markedly inhibited by teneligliptin, and AMP (p-adenosine 5'-monophosphate)-p-AMPK (activated protein kinase) levels were increased. Furthermore, the beneficial effects of teneligliptin on hyperglycaemia-induced cardiomyocytes were abolished by the AMPK signaling inhibitor compound C.

CONCLUSION

Overall, teneligliptin mitigated DCM by mitigating activation of the NLRP3 inflammasome.

Targeting autophagy with natural products as a potential therapeutic approach for diabetic microangiopathy

As the quality of life improves, the incidence of diabetes mellitus and its microvascular complications (DMC) continues to increase, posing a threat to people's health and wellbeing. Given the limitations of existing treatment, there is an urgent need for novel approaches to prevent and treat DMC. Autophagy, a pivotal mechanism governing metabolic regulation in organisms, facilitates the removal of dysfunctional proteins and organelles, thereby sustaining cellular homeostasis and energy generation. Anomalous states in pancreatic β-cells, podocytes, Müller cells, cardiomyocytes, and Schwann cells in DMC are closely linked to autophagic dysregulation. Natural products have the property of being multi-targeted and can affect autophagy and hence DMC progression in terms of nutrient perception, oxidative stress, endoplasmic reticulum stress, inflammation, and apoptosis. This review consolidates recent advancements in understanding DMC pathogenesis via autophagy and proposes novel perspectives on treating DMC by either stimulating or inhibiting autophagy using natural products.

Ginsenoside Rd Attenuates Myocardial Ischemia/Reperfusion Injury by Inhibiting Inflammation and Apoptosis through PI3K/Akt Signaling Pathway

Myocardial ischemia/reperfusion (I/R) injury is the leading cause of death worldwide. Ginsenoside Rd (GRd) has cardioprotective properties but its efficacy and mechanism of action in myocardial I/R injury have not been clarified. This study investigated GRd as a potent therapeutic agent for myocardial I/R injury. Oxygen-glucose deprivation and reperfusion (OGD/R) and left anterior descending (LAD) coronary artery ligation were used to establish a myocardial I/R injury model in vitro and in vivo. In vivo, GRd significantly reduced the myocardial infarct size and markers of myocardial injury and improved the cardiac function in myocardial I/R injury mice. In vitro, GRd enhanced cell viability and protected the H9c2 rat cardiomyoblast cell line from OGD-induced injury GRd. The network pharmacology analysis predicted 48 potential targets of GRd for the treatment of myocardial I/R injury. GO and KEGG enrichment analysis indicated that the cardioprotective effects of GRd were closely related to inflammation and apoptosis mediated by the PI3K/Akt signaling pathway. Furthermore, GRd alleviated inflammation and cardiomyocyte apoptosis in vivo and inhibited OGD/R-induced apoptosis and inflammation in cardiomyocytes. GRd also increased PI3K and Akt phosphorylation, suggesting activation of the PI3K/Akt pathway, whereas LY294002, a PI3K inhibitor, blocked the GRd-induced inhibition of OGD/R-induced apoptosis and inflammation in H9c2 cells. The therapeutic effect of GRd in vivo and in vitro against myocardial I/R injury was primarily dependent on PI3K/Akt pathway activation to inhibit inflammation and cardiomyocyte apoptosis. This study provides new evidence for the use of GRd as a cardiovascular drug.

The Flt3-inhibitor quizartinib augments apoptosis and promotes maladaptive remodeling after myocardial infarction in mice

BACKGROUND

Tyrosine kinase inhibitors (TKIs) targeting fms-like tyrosine kinase 3 (Flt3) such as quizartinib were specifically designed for acute myeloid leukemia treatment, but also multi-targeting TKIs applied to solid tumor patients inhibit Flt3. Flt3 is expressed in the heart and its activation is cytoprotective in myocardial infarction (MI) in mice.

OBJECTIVES

We sought to test whether Flt3-targeting TKI treatment aggravates cardiac injury after MI.

METHODS AND RESULTS

Compared to vehicle, quizartinib (10 mg/kg/day, gavage) did not alter cardiac dimensions or function in healthy mice after four weeks of therapy. Pretreated mice were randomly assigned to MI or sham surgery while receiving quizartinib or vehicle for one more week. Quizartinib did not aggravate the decline in ejection fraction, but significantly enhanced ventricular dilatation one week after infarction. In addition, apoptotic cell death was significantly increased in the myocardium of quizartinib-treated compared to vehicle-treated mice. In vitro, quizartinib dose-dependently decreased cell viability in neonatal rat ventricular myocytes and in H9c2 cells, and increased apoptosis as assessed in the latter. Together with H2O2, quizartinib potentiated the phosphorylation of the pro-apoptotic mitogen activated protein kinase p38 and augmented H2O2-induced cell death and apoptosis beyond additive degree. Pretreatment with a p38 inhibitor abolished apoptosis under quizartinib and H2O2.

CONCLUSION

Quizartinib potentiates apoptosis and promotes maladaptive remodeling after MI in mice at least in part via a p38-dependent mechanism. These findings are consistent with the multi-hit hypothesis of cardiotoxicity and make cardiac monitoring in patients with ischemic heart disease under Flt3- or multi-targeting TKIs advisable.

Research Progress on Histone Deacetylases Regulating Programmed Cell Death in Atherosclerosis

Histone deacetylases (HDACs) are epigenetic modifying enzyme that is closely related to chromatin structure and gene transcription, and numerous studies have found that HDACs play an important regulatory role in atherosclerosis disease. Apoptosis, autophagy and programmed necrosis as the three typical programmed cell death modalities that can lead to cell loss and are closely related to the developmental process of atherosclerosis. In recent years, accumulating evidence has shown that the programmed cell death mediated by HDACs is increasingly important in the pathophysiology of atherosclerosis. This paper first gives a brief overview of HDACs, the mechanism of programmed cell death, and their role in atherosclerosis, and then further elaborates on the role and mechanism of HDACs in regulating apoptosis, autophagy, and programmed necrosis in atherosclerosis, respectively, to provide new effective measures and theoretical basis for the prevention and treatment of atherosclerosis.

Predicting Endothelium-Dependent Diastolic Function (FMD) and Its Correlation with the Degree of Coronary Artery Disease (CAD) and Plaque Vulnerability for Cardiovascular Events

Objective

This study aims to investigate the correlation between vascular endothelium-dependent diastolic function (FMD) and the degree of coronary artery disease (CAD), plaque vulnerability, and its predictive value for cardiovascular events.

Methods

Initially, patients (n=100) who were admitted from January 2020 to January 2021 and intended to undergo percutaneous coronary intervention (PCI) were selected. Further, FMD in all patients was determined before the procedure and divided into a high-FMD group (≥4.2%) and a low-FMD group (<4.2%). Further, the data of two groups, including general information, coronary artery lesions, and plaque fibrous cap, were compared. Finally, the relationship between FMD and the degree of coronary artery lesions and plaque vulnerability was analyzed.

Results

No significant differences were observed concerning general information, number of coronary arteries-associated branches, lesion type, involvement of the left main stem (LM), the proportion of chronic occluded lesions (CTO), and lipid pool angle between the low-FMD group and the high-FMD group (P > 0.05). Nevertheless, the degree of stenosis of the lesions in the low-FMD group was significantly higher than in the high-FMD group (P < 0.05). In addition, the thickness of the fibrous cap was considerably lower than that in the high-FMD group (P < 0.05). Moreover, the incidence rate of TCFA was significantly higher than the high-FMD group (P < 0.05). The correlation analysis showed that FMD was significantly negatively correlated with the degree of coronary artery lesion stenosis and TCFA (P < 0.05) and positively correlated with the fibrous cap thickness (P < 0.05).

Conclusion

Overall, a negative correlation between FMD and the degree of coronary stenosis, plaque vulnerability, and a high predictive value for post-PCI cardiovascular events suggested that FMD could be a critical diagnostic marker for CAD.

Prothioconazole exposure disrupts oocyte maturation and fertilization by inducing mitochondrial dysfunction and apoptosis in mice

Prothioconazole (PTC), a novel broad-spectrum triazole fungicide, has attracted widespread concern due to its wide use and toxicological effects on non-target organisms. However, little is known about the impact of PTC on oocyte quality and female fertility, especially on oocyte maturation and fertilization. In the present study, we reported that PTC exposure affects the oocyte developmental competence and oocyte fertilization ability to weaken female fertility. Firstly, PTC compromises oocyte development ability by disrupting spindle morphology and chromosome alignment, as well as decreasing acetylation level of α-tubulin and disrupting kinetochore-microtubule attachments. In addition, PTC compromises oocyte fertilization ability by weakening the sperm binding ability and impairing the dynamics of Juno, Cortical granule and Ovastacin. Finally, single-cell transcriptome analysis revealed that PTC exposure has potentially toxic effects on oocyte development and fertilization, which is caused by the mitochondrial dysfunction and the occurrence of oxidative stress and apoptosis. In summary, our results indicated that PTC exposure had potentially toxic effects on female fertility and led to poor oocyte quality in female mice.

The Role of Pyroptosis and Autophagy in the Nervous System

Autophagy is a conservative self-degradation system, which includes the two major processes of enveloping abnormal proteins, organelles and other macromolecules, and transferring them into lysosomes for the subsequent degradation. It holds the stability of the intracellular environment under stress. So far, three types of autophagy have been found: microautophagy, chaperone-mediated autophagy and macroautophagy. Many diseases have the pathological process of autophagy dysfunction, such as nervous system diseases. Pyroptosis is one kind of programmed cell death mediated by gasdermin (GSDM). In this process of pyroptosis, the activated caspase-3, caspase-4/5/11, or caspase-1 cleaves GSDM into the N-terminal pore-forming domain (PFD). The oligomer of PFD combines with the cell membrane to form membrane holes, thus leading to pyroptosis. Pyroptosis plays a key role in multiple tissues and organs. Many studies have revealed that autophagy and pyroptosis participate in the nervous system, but the mechanisms need to be fully clarified. Here, we focused on the recent articles on the role and mechanism of pyroptosis and autophagy in the pathological processes of the nervous system.

Cell death in atherosclerosis

A complex and evolutionary process that involves the buildup of lipids in the arterial wall and the invasion of inflammatory cells results in atherosclerosis. Cell death is a fundamental biological process that is essential to the growth and dynamic equilibrium of all living things. Serious cell damage can cause a number of metabolic processes to stop, cell structure to be destroyed, or other irreversible changes that result in cell death. It is important to note that studies have shown that the two types of programmed cell death, apoptosis and autophagy, influence the onset and progression of atherosclerosis by controlling these cells. This could serve as a foundation for the creation of fresh atherosclerosis prevention and treatment strategies. Therefore, in this review, we summarized the molecular mechanisms of cell death, including apoptosis, pyroptosis, autophagy, necroptosis, ferroptosis and necrosis, and discussed their effects on endothelial cells, vascular smooth muscle cells and macrophages in the process of atherosclerosis, so as to provide reference for the next step to reveal the mechanism of atherosclerosis.

Sodium butyrate exerts a neuroprotective effect in rats with acute carbon monoxide poisoning by activating autophagy through the mTOR signaling pathway

Acute carbon monoxide (CO) poisoning is a prevalent type of poisoning that causes significant harm globally. Delayed encephalopathy after acute carbon monoxide poisoning (DEACMP) is a severe complication that occurs after acute CO poisoning; however, the exact underlying pathological cause of DEACMP remains unclear. Accumulating evidence indicates that abnormal inflammation and immune-mediated brain damage, cellular apoptosis and autophagy, and direct neuronal toxicity are involved in the development of delayed neurologic sequelae. Sodium butyrate, a histone deacetylase inhibitor, has gained increasing attention for its numerous beneficial effects on various diseases, such as obesity, diabetes, inflammatory diseases, and cerebral damage. In this study, an acute carbon monoxide poisoning (ACOP) model is established in rats to investigate the mechanism of CO poisoning and the therapeutic potential of sodium butyrate. The results suggested that the ACOP rats had impaired spatial memory, and cell apoptosis was observed in the hippocampi with activated autophagy. Sodium butyrate treatment further increased the activation of autophagy in the hippocampi of CO-exposed rats, inhibited apoptosis, and consolidated spatial memory. These findings indicated that sodium butyrate may improve memory and cognitive function in ACMP rats by promoting autophagy and inhibiting apoptosis.

LncRNA 220, a newly discovered long non-conding RNA inhibiting apoptosis and autophagy in Kupffer cells in LPS-induced endotoxemic mice through the XBP1u-PI3K-AKT pathway

Sepsis is recognized as a potentially fatal condition characterized by acute organ dysfunction resulting from an imbalanced immune response to infection. Acute liver injury (ALI) arises as an inflammatory outcome of immune response dysregulation associated with sepsis. Kupffer cells, which are liver-specific macrophages, are known to have a significant impact on ALI, although the precise regulatory mechanism remains unclear. Numerous studies have showcased the regulatory impact of long non-coding RNAs (lncRNAs) on the progression of diverse ailments, yet their precise regulatory mechanisms remain predominantly unexplored. In this study, a novel long non-coding RNA (lncRNA), referred to as lncRNA 220, was discovered using high-throughput sequencing. The expression of lncRNA 220 was found to be significantly elevated in the livers of mice with lipopolysaccharide (LPS)-induced endotoxemia, specifically during the 8-hour time period. Furthermore, in Kupffer cells treated with LPS, lncRNA 220 was observed to inhibit apoptosis and autophagy by activating the PI3K-AKT-mTORC1 pathway. This effect was achieved through the reduction of X-box protein 1 unspliced (Xbp1u) mRNA stability and suppression of its translation in the context of endoplasmic reticulum stress (ERS). Ultimately, this intervention mitigated the progression of LPS-induced ALI. To summarize, our study establishes lncRNA 220 as a newly identified regulator that suppresses apoptosis and autophagy in Kupffer cells subjected to LPS treatment, indicating its potential as a molecular target for ALI in endotoxemic mice.

Efficacy and safety of tongxinluo capsule for angina pectoris of coronary heart disease: an overview of systematic reviews and meta-analysis

Background

Tongxinluo capsule (TXLC) is a common drug for treating angina pectoris of coronary heart disease (CHD). In recent years, many systematic reviews (SRs) and meta-analyses (MAs) have reported the efficacy and safety of TXLC for improving angina symptoms in patients with CHD. We aimed to comprehensively evaluate the existing SRs and MAs of TXLC in treating angina pectoris of CHD, summarize the evidence quality, and provide scientific evidence and recommendations.

Methods

We searched seven databases for relevant SRs/MAs published up to 1 June 2023. Two reviewers independently completed the literature retrieval, screening, and data extraction. We used A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2) to evaluate the methodological quality, the Risk of Bias in Systematic Reviews (ROBIS) to assess the risk of bias, and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) to determine the strength of the evidence. RevMan 5.3 was used to synthesize data.

Results

We identified 15 SRs/MAs, including 329 RCTs and 33,417 patients. According to the evaluation results of AMSTAR-2, only one SR was of high methodological quality, the others were very low. ROBIS assessment showed that one SR (6.67%) had a low risk, 3 SRs (20%) had an unclear risk, and 11 SRs (73.33%) had a high risk. We assessed 42 outcomes by the GRADE, 10 (23.81%) for moderate-quality evidence, 17 (40.48%) for low-quality evidence, and 15 (35.71%) for very-low-quality evidence. Mate-analysis showed that TXLC combined with conventional western medications improved electrocardiogram efficacy (RR = 1.38, 95% CI: 1.23-1.43, P < 0.001) and angina efficacy (OR = 3.58, 95% CI: 3.02-4.24, P < 0.001), reduced angina attack frequency (SMD = -0.54, 95% CI: -0.64 to -0.44, P < 0.001) and angina duration (SMD = -0.42, 95% CI: -0.57 to -0.28, P < 0.001), with general heterogeneity. The pooled results showed that TXLC appears to have some efficacy in improving cardiac function and relieving angina symptoms, but there is limited evidence that it improves cardiovascular event rates, hemorheology, lipids, or hs-CRP. In the assessment of drug safety, TXLC was associated with different degrees of adverse drug reactions.

Conclusion

Based on the evidence, TXLC may be effective as an adjuvant treatment for angina pectoris of CHD. However, the quality of the evidence is low, and the drug's safety must be carefully interpreted. In future studies, high-quality randomized controlled trials are needed to confirm the effectiveness and safety of TXLC.

Systematic Review Registration

http://www.crd.york.ac.uk/PROSPERO/, identifier (CRD42022365372).

Alkylation Repair Homolog 5 Regulates N(6)-methyladenosine (m6A) Methylation of Mitsugumin 53 to Attenuate Myocardial Infarction by Inhibiting Apoptosis and Oxidative Stress

ABSTRACT

N(6)-methyladenosine (m6A) methylation modification is involved in the progression of myocardial infarction (MI). In this study, we investigated the effects of demethylase alkylation repair homolog 5 (ALKBH5) on cell apoptosis and oxidative stress in MI. The ischemia/reperfusion (I/R) injury mouse model and hypoxia/reoxygenation (H/R) cell model were established. The levels of ALKBH5 and mitsugumin 53 (MG53) were measured by quantitative real-time polymerase chain reaction, immunohistochemical, and immunofluorescence analysis. Apoptosis was evaluated by TUNEL assay, flow cytometry, and western blot. Oxidative stress was assessed by antioxidant index kits. Methylation was analyzed by RNA binding protein immunoprecipitation (RIP), MeRIP, and dual-luciferase reporter assay. We observed that ALKBH5 and MG53 were highly expressed in MI. Overexpression of ALKBH5 inhibited H/R-induced cardiomyocyte apoptosis and oxidative stress in vitro, and it inhibited I/R-induced collagen deposition, cardiac function, and apoptosis in vivo. ALKBH5 could bind to MG53, inhibit m6A methylation of MG53, and increase its mRNA stability. Silencing of MG53 counteracted the inhibition of apoptosis and oxidative stress induced by ALKBH5. In conclusion, ALKBH5 suppressed m6A methylation of MG53 and inhibited MG53 degradation to inhibit apoptosis and oxidative stress of cardiomyocytes, thereby attenuating MI. The results provided a theoretical basis that ALKBH5 is a potential target for MI treatment.

Screening and Validation of Key Genes of Autophagy in Acute Myocardial Infarction Based on Bioinformatics

Aims

Autophagy plays a significant role in the development of acute myocardial infarction (AMI), and cardiomyocyte autophagy is of major importance in maintaining cardiac function. We aimed to identify key genes associated with autophagy in AMI through bioinformatics analysis and verify them through clinical validation.

Materials and Methods

We downloaded an AMI expression profile dataset GSE166780 from Gene Expression Omnibus (GEO). Autophagy-associated genes potentially differentially expressed in AMI were screened using R software. Then, to identify key autophagy-related genes, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, protein-protein interaction (PPI) analysis, Receiver Operating Characteristic (ROC) curve analysis, and correlation analysis were performed on the differentially expressed autophagy-related genes in AMI. Finally, we used quantificational real-time polymerase chain reaction (qRT-PCR) to verify the RNA expression of the screened key genes.

Results

TSC2, HSPA8, and HIF1A were screened out as key autophagy-related genes. qRT-PCR results showed that the expression levels of HSPA8 and TSC2 in AMI blood samples were lower, while the expression level of HIF1A was higher than that in the healthy controls.

Conclusions

TSC2, HSPA8, and HIF1A were identified as key autophagy-related genes in this study. They may influence the development of AMI through autophagy. These findings may help deepen our understanding of AMI and may be useful for the treatment of AMI.

Knowledge domain and emerging trends of autophagy in cardiovascular research: A bibliometric analysis

BACKGROUND

Autophagy is essential for the homeostasis and function of the cardiovascular system. Citespace is a visual analysis software developed in the context of scientometrics and data visualization. The purpose of this study is to use Citespace software to conduct bibliometric and visual analysis of the research on autophagy in cardiovascular diseases, identify the current status, hot spots and trends in this field, help researchers clarify the future research focus and direction of autophagy in cardiovascular diseases, and provide more positive and broader ideas for the treatment and drug development of cardiovascular diseases.

METHODS

In the Web of Science Core Collection database to download the data from 2004 to 2022 regarding autophagy in cardiovascular research. CitespaceV was used to collect the research status, hotspots and development trends for visual analysis.

RESULTS

The 3568 articles were published by 547 authors from 397 institutions in 75 countries. From 2004 to 2021, the annual publications increased over time. The top 3 productive nations were China, the United States, and Germany. The leading institution was China's Fudan University. The most cited paper is Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition). The research hotpots include monitoring methods for autophagy activity, changes in autophagy levels in different types of cardiovascular diseases, autophagy signal transduction mechanism in cardiovascular diseases, etc.

CONCLUSION

Bibliometric analysis provided valuable information for autophagy research in cardiovascular disease, which is full of opportunities and challenges. The research of autophagy in the field of cardiovascular diseases is still worthy of in-depth exploration. A challenge with autophagy-targeted therapies is their dichotomy in which the goal is to target maladaptive autophagy while maintaining a baseline level of cell survival to optimize a beneficial outcome. It is necessary for scientists to develop new methods to evaluate the level of autophagy from basic application to human body and reveal the signaling mechanism of autophagy in different types of cardiovascular diseases.

Unveiling HPV's hidden link: Cardiovascular diseases and the viral intrigue

Cardiovascular diseases (CVD) remain a major global health challenge, with an escalating impact on mortality despite advancements in managing conventional risk factors. This review investigates the intricate relationship between human papillomavirus (HPV) and CVD, shedding light on a novel aspect of cardiovascular health. Despite significant progress in understanding and managing traditional CVD risk factors, a substantial proportion of CVD cases lack these conventional markers. Recent research has unveiled HPV, a prevalent sexually transmitted infection, as a potential unconventional risk factor for CVD. This review delves into the underlying mechanisms linking HPV to CVD pathogenesis. HPV's influence on vascular endothelium and induction of systemic inflammation are key contributors. Additionally, HPV disrupts host lipid metabolism, further exacerbating the development of atherosclerosis. The link between HPV and CAD is not merely correlative; it encompasses a complex interplay of virological, immunological, and metabolic factors. Understanding the connection between HPV and CVD holds transformative potential. Insights from this review not only underscore the significance of considering HPV as a crucial risk factor but also advocate for targeted HPV screening and vaccination strategies to mitigate CVD risks. This multidisciplinary exploration bridges the gap between infectious diseases and cardiovascular health, emphasizing the need for a comprehensive approach to combating the global burden of cardiovascular disease. Further research and clinical guidelines in this realm are essential to harness the full scope of preventive and therapeutic interventions, ultimately shaping a healthier cardiovascular landscape.

The research progress of crosstalk mechanism of autophagy and apoptosis in diabetic vascular endothelial injury

In recent years, the widespread prevalence of diabetes has become a major killer that threatens the health of people worldwide. Of particular concern is hyperglycemia-induced vascular endothelial injury, which is one of the factors that aggravate diabetic vascular disease. During the process of diabetic vascular endothelial injury, apoptosis is an important pathological manifestation and autophagy is a key regulatory mechanism. Autophagy and apoptosis interact with each other. Hence, the crosstalk mechanism between the two processes is an important means of regulating diabetic vascular endothelial injury. This article reviews the research progress in apoptosis in the context of diabetic vascular endothelial injury and discusses the crosstalk mechanism of autophagy and apoptosis and its role in this injury. The purpose is to guide the prevention and treatment of diabetic vascular endothelial injury in the future.

Correlation of Serum Endocan Level With Apoptosis Indicators and Severity of Atherosclerotic Lesions of Coronary Arteries in Patients With Coronary Heart Disease

Aim    To study the relationship of blood serum concentration of endocan with indexes of apoptosis and clinical and instrumental characteristics of patients with ischemic heart disease (IHD).Material and methods    The study included 176 subjects (105 men and 71 women). 150 of them were diagnosed with IHD and 26 were healthy volunteers. Anthropometric measurements, coronary angiography, echocardiography, duplex ultrasound scanning of extracranial parts of the brachiocephalic arteries were performed for all patients. Concentrations of endocan (ng / ml), glucose (mmol / l), and apoptotic markers Bcl-2 (ng / ml), Bax (ng / ml), Bcl-2 / Bax, TRAIL (pg / ml), and p53 (ng / ml) were measured in blood serum. Patients were divided into groups based on their SYNTAX scores: group 1 with moderate atherosclerotic lesions of the coronary arteries (CA) (score < 22, 78 patients); group 2 with severe CA atherosclerosis (score 23-32, 37 patients); and group 3 with extremely severe CA lesions (score >33, 35 patients). The control group consisted of healthy volunteers (26 subjects). All groups were age- and sex-matched. Differences were considered statistically significant at p<0.05.Results    A correlation was found between endocan concentration and IHD severity (r=0.32, p<0.001). In group 1, the median endocan concentration was 14.57 ng / ml [8.21; 23.66], in group 2, 19.34 ng / ml [8.425; 26.645], in group 3, 32.13 ng / ml [18.2; 39.12], and in the control group, 6.92 ng / ml [4.62; 9.18]. Correlations of varying strength and significance were observed between the endocan concentration and a number of clinical and instrumental characteristics. Endocan concentrations significantly differed in groups of patients with multifocal atherosclerosis (p<0.01), angina pectoris (p<0.01), a history of myocardial infarction (p<0.001), and obesity (p<0.05) from patients without these signs. Also, a correlation was found between serum endocan concentration and apoptotic markers: TRAIL (r= -0.448, p<0.001); BCL-2 (r= -0.552, p<0.001), Bax (r= -0.519, p<0.001), Bcl-2 / Bax (r= -0.576, p<0.001) and p53 (r= -0.520, p <0.001).Conclusion    The study demonstrated a potential role of endocan as a promising biomarker for risk stratification, prognosis and therapeutic monitoring of IHD patients.

Luteolin Pretreatment Ameliorates Myocardial Ischemia/Reperfusion Injury by lncRNA-JPX/miR-146b Axis

Background

In the present study, we aimed to find out whether luteolin (Lut) pretreatment could ameliorate myocardial ischemia/reperfusion (I/R) injury by regulating the lncRNA just proximal to XIST (JPX)/microRNA-146b (miR-146b) axis.

Methods

We established the models in vitro (HL-1 cells) and in vivo (C57BL/6J mice) to certify the protection mechanism of Lut pretreatment on myocardial I/R injury. Dual luciferase reporter gene assay was utilized for validating that JPX could bind to miR-146b. JPX and miR-146b expression levels were determined by RT-qPCR. Western blot was utilized to examine apoptosis-related protein expression levels, including cleaved caspase-9, caspase-9, cleaved caspase-3, caspase-3, Bcl-2, Bax, and BAG-1. Apoptosis was analyzed by Annexin V-APC/7-AAD dualstaining, Hoechst 33342 staining, as well as flow cytometry. Animal echocardiography was used to measure cardiac function (ejection fraction (EF) and fractional shortening (FS) indicators).

Results

miR-146b was demonstrated to bind and recognize the JPX sequence site by dual luciferase reporter gene assay. The expression level of miR-146b was corroborated to be enhanced by H/R using RT-qPCR (P < 0.001 vs. Con). Moreover, JPX could reduce the expression of miR-146b, whereas inhibiting JPX could reverse the alteration (P < 0.001 vs. H/R, respectively). Western blot analysis demonstrated that Lut pretreatment increased BAG-1 expression level and Bcl-2/Bax ratio, but diminished the ratio of cleaved caspase 9/caspase 9 and cleaved caspase 3/caspase 3 (P < 0.001 vs. H/R, respectively). Moreover, the cell apoptosis change trend, measured by Annexin V-APC/7-AAD dualstaining, Hoechst 33342 staining, along with flow cytometry, was consistent with that of apoptosis-related proteins. Furthermore, pretreatment with Lut improved cardiac function (EF and FS) (P < 0.001 vs. I/R, respectively), as indicated in animal echocardiography.

Conclusion

Our results demonstrated that in vitro and in vivo, Lut pretreatment inhibited apoptosis via the JPX/miR-146b axis, ultimately improving myocardial I/R injury.

Everolimus prevents doxorubicin-induced apoptosis in H9c2 cardiomyocytes but not in MCF-7 cancer cells: Cardioprotective roles of autophagy, mitophagy, and AKT

Cardiotoxicity is a severe side effect of the chemotherapeutic agent doxorubicin (DOX). We recently showed that DOX-induced cardiomyocyte apoptosis and death were attenuated through autophagy pre-induction. Herein, we assessed how the autophagy/mitophagy-inducing antitumor drug everolimus (EVL) affected DOX-induced cytotoxicity in the rat cardiomyocyte cell line H9c2 and human breast cancer cell line MCF-7. Apoptosis was assessed using annexin V assay. Autophagy and mitophagy were assessed using fluorescence assays. Cellular protein levels were determined using western blotting. Pretreatment with EVL (1 nM) before DOX exposure inhibited mammalian target of rapamycin (mTOR) activity, induced autophagy and mitophagy, and activated protein kinase B (AKT) in H9c2 cells. In mitochondria, DOX (1 μM) induced structural damage (decreased membrane potential and release of cytochrome c), increased superoxide levels, decreased apoptosis inhibitor Bcl-2, and increased apoptosis inducer Bax, leading to apoptosis and reduced viability in H9c2 cells. EVL pretreatment suppressed DOX-induced changes. EVL anti-apoptotic effects were inhibited by treatment with MK-2206, a selective AKT inhibitor. Furthermore, EVL suppressed DOX-induced cardiotoxicity through autophagy/mitophagy and AKT activation but did not attenuate DOX-induced apoptosis or reduction in viability in MCF-7 cells. Altogether, EVL can protect cardiomyocytes from DOX-induced apoptosis and toxicity without reducing DOX antitumor effects, allowing safer chemotherapy.

Anti-heart failure mechanism of saponin extract of black ginseng based on metabolomics

OBJECTIVE

This study aimed to explore the mechanism of total saponin of black ginseng (TSBG) in treating heart failure (HF) in DOX-induced HF model rats.

METHODS

Rats with HF induced by the intraperitoneal injection of DOX were treated with TSBG (low dose, 30 mg/kg/day; medium dose, 60 mg/kg/day; high dose, 120 mg/kg/day) and shakubar trivalsartan (80 mg/kg/day, positive control) for four weeks. Serum BNP and ANP levels were tested by ELISA, and pathological tissue sections were examined. Serum metabolites were measured using nontargeted metabolomic techniques. The expression of Akt/mTOR autophagy-associated proteins in heart tissue was detected using Western blot, including Beclin1, p62, LCII and LC3I.

RESULTS

Compared with the model group, rats in the TSBG-H group had a significantly lower heart index (p < 0.05), significantly lower serum levels of BNP (p < 0.01) and ANP (p < 0.01) and significantly fewer cardiac histopathological changes. Metabolomic results showed that TSBG significantly back-regulated 12 metabolites (p < 0.05), including cholesterol, histamine, sphinganine, putrescine, arachidonic acid, 3-sulfinoalanine, hypotaurine, gluconic acid and lysoPC (18:0:0). These metabolite changes were involved in taurine and hypotaurine metabolism, arachidonic acid metabolism, sphingolipid metabolism, etc. The protein expression level of p-Akt/Akt and p-mTOR/mTOR was significantly up-regulated (p < 0.001), whereas that of Beclin1, p62 (p < 0.001) and LCII/LC3I was down-regulated (p < 0.05).

CONCLUSION

TSBG has an excellent therapeutic effect on DOX-induced HF in rats, probably by regulating the Akt/mTOR autophagy signalling pathway, resulting in the improvement of taurine and hypotaurine metabolism, arachidonic acid metabolism and sphingolipid metabolism, which may provide a reference for elucidating the potential mechanism of action of TSBG against HF.

Salvianolic acid B promotes angiogenesis and inhibits cardiomyocyte apoptosis by regulating autophagy in myocardial ischemia

BACKGROUND

Myocardial ischemia (MI) can cause angina, myocardial infarction, and even death. Angiogenesis is beneficial for ensuring oxygen and blood supply to ischemic tissue, promoting tissue repair, and reducing cell damage. In this study, we evaluated the effects of Salvianolic acid B (Sal B) against myocardial ischemia and explored its underlying mechanism on autophagy.

METHODS

The anti-apoptosis effect of Sal B was conducted by staining Annexin V-FITC/PI and Hoechst as well as evaluating apoptosis bio-markers at protein level in H9c2 cells at glucose deprivation condition. HUVECs were co-cultured with H9c2, and the tube formation assay was used to monitor Sal B's impact on angiogenesis. The MI model of mice was induced by intraperitoneal injection of isoproterenol (ISO). The effect of Sal B on MI mice was evaluated by HE, Masson, immunohistochemistry, WB and kits. In addition, Atg5 siRNA was applied to verify whether the protective effect of Sal B was regulated to autophagy.

RESULTS

In H9c2, Sal B reduced the levels of lactate dehydrogenase (LDH), malondialdehyde (MDA) and reactive oxygen species (ROS), improved the levels of superoxide dismutase (SOD) and mitochondrial membrane potential, downregulated the expressions of Bax and cleaved-Caspase3, upregulated the expression of Bcl-2. Therefore, Sal B could significantly inhibit the damage of H9c2 caused by glucose deprivation. In the co-culture system of H9c2 and HUVECs, vascular endothelial growth factor (VEGF) level in the supernatant was dramatically raised by Sal B. Sal B upregulated the expressions of VEGF, platelet derived growth factor (PDGF) and endothelial marker CD31. It implied that Sal B exerted a significant pro-angiogenic effect. Moreover, Sal B increased the expression of LC3, Atg5, and Beclin1, while reducing the level of P62. When the expression of Atg5 was inhibited, the protective effects of Sal B on apoptosis and angiogenesis was reversed.

CONCLUSIONS

Sal B inhibited cardiomyocyte apoptosis and promoted angiogenesis by regulating autophagy, thereby improving MI.

Association of inflammatory indicators with intensive care unit mortality in critically ill patients with coronary heart disease

Objective

Coronary heart disease (CHD) is one of the major cardiovascular diseases, a common chronic disease in the elderly and a major cause of disability and death in the world. Currently, intensive care unit (ICU) patients have a high probability of concomitant coronary artery disease, and the mortality of this category of patients in the ICU is receiving increasing attention. Therefore, the aim of this study was to verify whether the composite inflammatory indicators are significantly associated with ICU mortality in ICU patients with CHD and to develop a simple personalized prediction model.

Method

7115 patients from the Multi-Parameter Intelligent Monitoring in Intensive Care Database IV were randomly assigned to the training cohort (n = 5692) and internal validation cohort (n = 1423), and 701 patients from the eICU Collaborative Research Database served as the external validation cohort. The association between various inflammatory indicators and ICU mortality was determined by multivariate Logistic regression analysis and Cox proportional hazards model. Subsequently, a novel predictive model for mortality in ICU patients with CHD was developed in the training cohort and performance was evaluated in the internal and external validation cohorts.

Results

Various inflammatory indicators were demonstrated to be significantly associated with ICU mortality, 30-day ICU mortality, and 90-day ICU mortality in ICU patients with CHD by Logistic regression analysis and Cox proportional hazards model. The area under the curve of the novel predictive model for ICU mortality in ICU patients with CHD was 0.885 for the internal validation cohort and 0.726 for the external validation cohort. The calibration curve showed that the predicted probabilities of the model matched the actual observed probabilities. Furthermore, the decision curve analysis showed that the novel prediction model had a high net clinical benefit.

Conclusion

In ICU patients with CHD, various inflammatory indicators were independent risk factors for ICU mortality. We constructed a novel predictive model of ICU mortality risk in ICU patients with CHD that had great potential to guide clinical decision-making.

The Enhanced Effects of Swimming and Running Preconditioning in an Experimental Model of Myocardial Ischemia/Reperfusion Injury

Background and Objectives: This study was conducted to examine the influence of different swimming and running protocols as forms of physiological preconditioning on an isolated rat heart's ischemia/reperfusion injury. Materials and Methods: This study was conducted on 60 male Wistar albino rats (6 weeks old, bw: 200 ± 20 g), divided into: CTRL group-a sedentary control group; sAeT-a group that underwent aerobic swimming conditioning using a swimming protocol for 8 weeks; sAnT-a group that underwent anaerobic swimming conditioning; rAeT-a group that underwent aerobic running conditioning; and rAnT-a group that underwent anaerobic running conditioning. After the preconditioning protocols, ex vivo estimating of myocardial function according to the Langendorff technique was performed. Results: The anaerobic running training decreased heart rate and the anaerobic swimming training reduced coronary flow, demonstrating the difference in the physiological heart response of aerobic/anaerobic physical training (p < 0.05). Heart rate was significantly reduced in both training swimming groups after a period of ischemia (p < 0.05). On the other hand, the anaerobic running protocol induced a significantly decreased heart rate in comparison with the aerobic running group and the sedentary group (p < 0.05). Conclusions: The data from this experimental study support many protective training effects, i.e., improved contractility, improved resting heart rate, and increased physical work capacity and exercise tolerance. Physical training in the form of anaerobic running induces greater heart preconditioning for reperfusion injury in comparison with anaerobic swimming training.

Cornerstone Cellular Pathways for Metabolic Disorders and Diabetes Mellitus: Non-Coding RNAs, Wnt Signaling, and AMPK

Metabolic disorders and diabetes (DM) impact more than five hundred million individuals throughout the world and are insidious in onset, chronic in nature, and yield significant disability and death. Current therapies that address nutritional status, weight management, and pharmacological options may delay disability but cannot alter disease course or functional organ loss, such as dementia and degeneration of systemic bodily functions. Underlying these challenges are the onset of aging disorders associated with increased lifespan, telomere dysfunction, and oxidative stress generation that lead to multi-system dysfunction. These significant hurdles point to the urgent need to address underlying disease mechanisms with innovative applications. New treatment strategies involve non-coding RNA pathways with microRNAs (miRNAs) and circular ribonucleic acids (circRNAs), Wnt signaling, and Wnt1 inducible signaling pathway protein 1 (WISP1) that are dependent upon programmed cell death pathways, cellular metabolic pathways with AMP-activated protein kinase (AMPK) and nicotinamide, and growth factor applications. Non-coding RNAs, Wnt signaling, and AMPK are cornerstone mechanisms for overseeing complex metabolic pathways that offer innovative treatment avenues for metabolic disease and DM but will necessitate continued appreciation of the ability of each of these cellular mechanisms to independently and in unison influence clinical outcome.

The impact of aging and oxidative stress in metabolic and nervous system disorders: programmed cell death and molecular signal transduction crosstalk

Life expectancy is increasing throughout the world and coincides with a rise in non-communicable diseases (NCDs), especially for metabolic disease that includes diabetes mellitus (DM) and neurodegenerative disorders. The debilitating effects of metabolic disorders influence the entire body and significantly affect the nervous system impacting greater than one billion people with disability in the peripheral nervous system as well as with cognitive loss, now the seventh leading cause of death worldwide. Metabolic disorders, such as DM, and neurologic disease remain a significant challenge for the treatment and care of individuals since present therapies may limit symptoms but do not halt overall disease progression. These clinical challenges to address the interplay between metabolic and neurodegenerative disorders warrant innovative strategies that can focus upon the underlying mechanisms of aging-related disorders, oxidative stress, cell senescence, and cell death. Programmed cell death pathways that involve autophagy, apoptosis, ferroptosis, and pyroptosis can play a critical role in metabolic and neurodegenerative disorders and oversee processes that include insulin resistance, β-cell function, mitochondrial integrity, reactive oxygen species release, and inflammatory cell activation. The silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), AMP activated protein kinase (AMPK), and Wnt1 inducible signaling pathway protein 1 (WISP1) are novel targets that can oversee programmed cell death pathways tied to β-nicotinamide adenine dinucleotide (NAD+), nicotinamide, apolipoprotein E (APOE), severe acute respiratory syndrome (SARS-CoV-2) exposure with coronavirus disease 2019 (COVID-19), and trophic factors, such as erythropoietin (EPO). The pathways of programmed cell death, SIRT1, AMPK, and WISP1 offer exciting prospects for maintaining metabolic homeostasis and nervous system function that can be compromised during aging-related disorders and lead to cognitive impairment, but these pathways have dual roles in determining the ultimate fate of cells and organ systems that warrant thoughtful insight into complex autofeedback mechanisms.

Naringin improves post-ischemic myocardial injury by activation of KATP channels

Naringin (NRG) is a flavonoid with recognized cardioprotective effects. Then, it was investigated the cardioprotective mechanisms of NRG against ischemia-reperfusion (I/R) injury. The rats were pretreated for 7 days (v.o.) with NRG (25 mg/kg) or n-acetylcysteine (NAC, 100 mg/kg) and their isolated hearts were subjected to global ischemia (30 min) and reperfusion (60 min). Furthermore, isolated hearts were perfused with 5 μM NRG in the presence of 10 μM glibenclamide (GLI) and subjected to I/R protocol. In healthy ventricular cardiomyocyte, it was evaluated the acute effect of 5 μM NRG on the GLI sensitive current. The results showed that NRG pretreatment restored the cardiac function and electrocardiogram (ECG) alterations induced by I/R injury, decreasing arrhythmia scores and the occurrence of severe arrhythmias. Lactate dehydrogenase and infarct area were decreased while superoxide dismutase (SOD), catalase and citrate synthase activities increased. Expression of SOD CuZn and SOD Mn not was altered. NRG treatment decreased reactive oxygen species (ROS) generation and lipid peroxidation without alter sulfhydryl groups and protein carbonylation. Also, NRG (5 μM) increased the glibenclamide sensitive current in isolated cardiomyocytes. In isolated heart, the cardioprotection of NRG was significantly reduced by GLI. Furthermore, NRG promoted downregulation of Bax expression and Bax/Bcl-2. Histopathological analysis showed that NRG decreased cell edema, cardiomyocytes and nucleus diameter. Thus, NRG has a cardioprotective effect against cardiac I/R injury which is mediated by its antioxidant and antiapoptotic actions and KATP channels activation.

The purified extract of steamed Panax ginseng protects cardiomyocyte from ischemic injury via caveolin-1 phosphorylation-mediating calcium influx

Background

Caveolin-1, the scaffolding protein of cholesterol-rich invaginations, plays an important role in store-operated Ca2+ influx and its phosphorylation at Tyr14 (p-caveolin-1) is vital to mobilize protection against myocardial ischemia (MI) injury. SOCE, comprising STIM1, ORAI1 and TRPC1, contributes to intracellular Ca2+ ([Ca2+]i) accumulation in cardiomyocytes. The purified extract of steamed Panax ginseng (EPG) attenuated [Ca2+]i overload against MI injury. Thus, the aim of this study was to investigate the possibility of EPG affecting p-caveolin-1 to further mediate SOCE/[Ca2+]i against MI injury in neonatal rat cardiomyocytes and a rat model.

Methods

PP2, an inhibitor of p-caveolin-1, was used. Cell viability, [Ca2+]i concentration were analyzed in cardiomyocytes. In rats, myocardial infarct size, pathological damages, apoptosis and cardiac fibrosis were evaluated, p-caveolin-1 and STIM1 were detected by immunofluorescence, and the levels of caveolin-1, STIM1, ORAI1 and TRPC1 were determined by RT-PCR and Western blot. And, release of LDH, cTnI and BNP was measured.

Results

EPG, ginsenosides accounting for 57.96%, suppressed release of LDH, cTnI and BNP, and protected cardiomyocytes by inhibiting Ca2+ influx. And, EPG significantly relieved myocardial infarct size, cardiac apoptosis, fibrosis, and ultrastructure abnormality. Moreover, EPG negatively regulated SOCE via increasing p-caveolin-1 protein, decreasing ORAI1 mRNA and protein levels of ORAI1, TRPC1 and STIM1. More importantly, inhibition of the p-caveolin-1 significantly suppressed all of the above cardioprotection of EPG.

Conclusions

Caveolin-1 phosphorylation is involved in the protective effects of EPG against MI injury via increasing p-caveolin-1 to negatively regulate SOCE/[Ca2+]i.

Association of the L3MBTL3 rs1125970 and rs4897367 Gene Polymorphisms With Coronary Heart Disease Susceptibility in the Chinese Population: A Case-Control Study

ABSTRACT

Coronary heart disease (CHD) is a prevalent heart disease with high incidence and mortality rates worldwide, and its pathogenesis is related to genetic factors. L3MBTL3 has been reported to be potentially linked to CHD susceptibility. This study aims to explore the correlation between L3MBTL3 single nucleotide polymorphisms (SNPs) and CHD risk in the Chinese population. Three SNPs (rs1125970 A/T, rs4897367 T/C, and rs2068957 A/G) in L3MBTL3 from 649 patients with CHD and 649 healthy controls were genotyped using the Agena MassARRAY platform. The relationship between SNPs and CHD risk was evaluated by logistic regression analysis. Our study indicated that rs1125970 (TT: odds ratio [OR] = 0.76, P = 0.014) and rs4897367 (TT: OR = 0.74, P = 0.021) were related to a decreased susceptibility to CHD. Stratified analyses showed that rs1125970 could reduce the risk of CHD in males, subjects aged <60 years, with a body mass index <24 kg/m 2 , and nonhypertensive patients. rs4897367 exerted a risk-decreasing influence on CHD in nondiabetic patients. In the haplotype analysis, individuals with the T rs4897367 A rs2068957 haplotype were less likely to develop CHD (OR = 0.74, P = 0.024). In summary, L3MBTL3 rs1125970 and rs4897367 were significantly correlated with a decreased susceptibility to CHD in the Chinese population.

Potential relationship between autophagy and ferroptosis in myocardial ischemia/reperfusion injury

Autophagy is an evolutionarily conserved process involved in the degradation of long-lived proteins and excessive or dysfunctional organelles. As a pivotal cellular response, autophagy has been extensively studied and is known to be involved in various diseases. Ferroptosis is a recently discovered form of regulated cell death characterized by iron overload, leading to the accumulation of lethal levels of lipid hydroperoxides. Recently, an increasing number of studies have revealed a link between autophagy and ferroptosis. Myocardial ischemia/reperfusion injury (MIRI) is an urgent dilemma after myocardial infarction recanalization, which is regulated by several cell death pathways, including autophagy and ferroptosis. However, the potential relationship between autophagy and ferroptosis in MIRI remains unexplored. In this study, we briefly review the mechanisms of autophagy and ferroptosis, including their roles in MIRI. Moreover, we provide an overview of the potential crosstalk in MIRI. Clarifying the relationship between different cell death pathways may provide new ideas for the treatment of MIRI in the future.

Fatty acid metabolism disorders and potential therapeutic traditional Chinese medicines in cardiovascular diseases

Cardiovascular diseases are currently the primary cause of mortality in the whole world. Growing evidence indicated that the disturbances in cardiac fatty acid metabolism are crucial contributors in the development of cardiovascular diseases. The abnormal cardiac fatty acid metabolism usually leads to energy deficit, oxidative stress, excessive apoptosis, and inflammation. Targeting fatty acid metabolism has been regarded as a novel approach to the treatment of cardiovascular diseases. However, there are currently no specific drugs that regulate fatty acid metabolism to treat cardiovascular diseases. Many traditional Chinese medicines have been widely used to treat cardiovascular diseases in clinics. And modern studies have shown that they exert a cardioprotective effect by regulating the expression of key proteins involved in fatty acid metabolism, such as peroxisome proliferator-activated receptor α and carnitine palmitoyl transferase 1. Hence, we systematically reviewed the relationship between fatty acid metabolism disorders and four types of cardiovascular diseases including heart failure, coronary artery disease, cardiac hypertrophy, and diabetic cardiomyopathy. In addition, 18 extracts and eight monomer components from traditional Chinese medicines showed cardioprotective effects by restoring cardiac fatty acid metabolism. This work aims to provide a reference for the finding of novel cardioprotective agents targeting fatty acid metabolism.

Germacrone mitigates cardiac remodeling by regulating PI3K/AKT-mediated oxidative stress, inflammation, and apoptosis

Cardiac remodeling is a common consequence of cardiovascular diseases and is closely associated with oxidative stress, inflammation, and apoptosis. Germacrone, a bioactive compound present in Rhizoma curcuma, has been shown to possess anti-oxidative, anti-inflammatory, and anti-apoptotic properties. The aim of this study was to investigate the protective effect of germacrone against cardiac remodeling. Here, C57BL/6 mice were subcutaneous injection with isoproterenol (ISO) once daily for two weeks and were concurrent intragastric injection of germacrone. In vitro, neonatal rat cardiomyocytes (NRCMs) were used to verify the protective effect of germacrone on ISO-induced cardiac injury. Our findings indicated that ISO induce oxidative stress, inflammation, and apoptosis in vivo and in vitro, while germacrone treatment significantly attenuates these effects, thereby attenuating myocardium remodeling and cardiac dysfunction. Mechanistically, germacrone reduced cardiac remodeling-induced activation of phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway, and the cardioprotective effects of germacrone were abrogated by a PI3K agonist. In conclusion, our results suggest that germacrone attenuates oxidative stress, inflammation, and apoptosis in cardiac remodeling by inhibiting the PI3K/AKT pathway, and may therefore represent a promising therapeutic approach for the treatment of cardiac remodeling.

p53 contributes to cardiovascular diseases via mitochondria dysfunction: A new paradigm

Cardiovascular diseases (CVDs) are leading causes of global mortality; however, their underlying mechanisms remain unclear. The tumor suppressor factor p53 has been extensively studied for its role in cancer and is also known to play an important role in regulating CVDs. Abnormal p53 expression levels and modifications contribute to the occurrence and development of CVDs. Additionally, mounting evidence underscores the critical involvement of mitochondrial dysfunction in CVDs. Notably, studies indicate that p53 abnormalities directly correlate with mitochondrial dysfunction and may even interact with each other. Encouragingly, small molecule inhibitors targeting p53 have exhibited remarkable effects in animal models of CVDs. Moreover, therapeutic strategies aimed at mitochondrial-related molecules and mitochondrial replacement therapy have demonstrated their advantageous potential. Therefore, targeting p53 or mitochondria holds immense promise as a pioneering therapeutic approach for combating CVDs. In this comprehensive review, we delve into the mechanisms how p53 influences mitochondrial dysfunction, including energy metabolism, mitochondrial oxidative stress, mitochondria-induced apoptosis, mitochondrial autophagy, and mitochondrial dynamics, in various CVDs. Furthermore, we summarize and discuss the potential significance of targeting p53 or mitochondria in the treatment of CVDs.

Dexmedetomidine Ameliorates Cardiac Ischemia/Reperfusion Injury by Enhancing Autophagy Through Activation of the AMPK/SIRT3 Pathway

Objective

Myocardial ischemia-reperfusion (I/R) injury is a detrimental disease, resulting in high morbidity and mortality globally. In this study, we aimed to investigate the role of Dex in mitigating cardiac I/R injury.

Methods

H9c2 cells were treated with Dex (1 μM) for 24 h followed by oxygen-glucose deprivation/re-oxygenation (OGD/R). ANP and BNP mRNA of H9c2 cells and the LDH release were measured. Apoptosis of H9c2 cells was analyzed by flow cytometry. Mitochondrial membrane potential and superoxide production were detected by JC-1 staining and MitoSOXTM Red, respectively. Cell aerobic respiration was measured using Seahorse analysis. In vivo, mice were injected with Dex (25 μg/kg, i.p., once daily) for 5 days and then subjected to heart I/R. Heart function was analyzed by echocardiography. CK-MB and LDH were measured by Elisa. Infarct size was measured using TTC-Evans blue staining. Mitochondrial ultrastructure was observed using transmission electron microscopy. DHE staining, SOD activity, the content of MDA, and the content of GSH/GSSG of heart were measured to evaluate the oxidative stress. In addition, inflammatory cytokines were measured in vivo and in vitro. Furthermore, AMPK, SIRT3, and autophagy-related protein expression in the heart were detected by Western blot.

Results

Dex reduced the H9c2 cells injury exposed to OGD/R, accompanied by improved mitochondrial function and membrane potential. In vivo, Dex improved heart function, myocardial injury, and the mitochondria ultrastructure following I/R injury. Meanwhile, Dex inhibited myocardial oxidative stress and inflammation in the myocardial I/R. Furthermore, Compound C (an AMPK inhibitor) could inhibit Dex-induced autophagy in the I/R heart and the 3-MA (an autophagy inhibitor) could partially interfere with the effects of Dex on the protection of I/R heart.

Conclusion

Dex suppressed oxidative stress and inflammation by promoting autophagy through activating the AMPK/SIRT3 pathway, thus protecting the heart against the I/R injury.

The Mechanisms of Ferroptosis Under Hypoxia

Ferroptosis is a new form of programmed cell death, which is characterized by the iron-dependent accumulation of lipid peroxidation and increase of ROS, resulting in oxidative stress and cell death. Iron, lipid, and multiple signaling pathways precisely control the occurrence and implementation of ferroptosis. The pathways mainly include Nrf2/HO-1 signaling pathway, p62/Keap1/Nrf2 signaling pathway. Activating p62/Keap1/Nrf2 signaling pathway inhibits ferroptosis. Nrf2/HO-1 signaling pathway promotes ferroptosis. Furthermore, some factors also participate in the occurrence of ferroptosis under hypoxia, such as HIF-1, NCOA4, DMT1. Meanwhile, ferroptosis is related with hypoxia-related diseases, such as MIRI, cancers, and AKI. Accordingly, ferroptosis appears to be a therapeutic target for hypoxia-related diseases.

Knockdown of Mmu-circ-0001380 Attenuates Myocardial Ischemia/Reperfusion Injury via Modulating miR-106b-5p/Phlpp2 Axis

Myocardial ischemia/reperfusion (MI/R) injury induces myocardial damage and dysfunction. Increasing evidence has confirmed that circular RNAs (circRNAs) play crucial roles in regulating MI/R. Mmu-circ-0001380 has identified to be highly expressed in myocardium of MI/R mouse model. However, its biological function and molecular mechanism in MI/R injury are still unclear. Here, we demonstrated that knockdown of cric-0001380 attenuated myocardial injury of MI/R mice. In vitro, silence of circ-0001380 significantly enhanced viability, and inhibited apoptosis and oxidative stress in HL-1 cells under oxygen-glucose deprivation/reoxygenation (OGD/R). Mmu-miR-106b-5p interacted with circ-0001380, and suppressed the expression of pleckstrin homology domain and leucine rich repeat protein phosphatase 2 (Phlpp2). The miR-106b-5p/Phlpp2 axis mediated the effect of circ-0001380 on OGD/R-induced apoptosis through regulating the phosphorylation of p38, and further involved in regulating the viability and oxidative stress of HL-1 cells. In conclusion, circ-0001380 downregulation relieves MI/R injury via regulating the miR-106b-5p/Phlpp2 axis. The present study indicates that mmu-circ-0001380 exacerbates the myocardial ischemia/reperfusion injury through modulating the miR-106b-5p/Phlpp2 axis in vitro and in vivo.

Complement C3 Reduces Apoptosis via Interaction with the Intrinsic Apoptotic Pathway

Myocardial ischemia/reperfusion (I/R) elicits an acute inflammatory response involving complement factors. Recently, we reported that myocardial necrosis was decreased in complement C3-/- mice after heart I/R. The current study used the same heart model to test the effect of C3 on myocardial apoptosis and investigated if C3 regulation of apoptosis occurred in human cardiomyocytes. Comparative proteomics analyses found that cytochrome c was present in the myocardial C3 complex of WT mice following I/R. Incubation of exogenous human C3 reduced apoptosis in a cell culture system of human cardiomyocytes that did not inherently express C3. In addition, human C3 inhibited the intrinsic apoptosis pathway in a cell-free apoptosis system. Finally, human pro-C3 was found to bind with an apoptotic factor, pro-caspase 3, in a cell-free system. Thus, we present firsthand evidence showing that C3 readily reduces myocardial apoptosis via interaction with the intrinsic apoptotic pathway.