Geniposide suppresses NLRP3 inflammasome-mediated pyroptosis via the AMPK signaling pathway to mitigate myocardial ischemia/reperfusion injury

β-Sitosterol suppresses NLRP3 Inflammasome activation and Pyroptosis in myocardial ischemia/reperfusion injury via inhibition of PPARγ2

BACKGROUND

β-Sitosterol, a plant-derived sterol, has demonstrated potential therapeutic effects in cardiovascular diseases, particularly myocardial ischemia-reperfusion injury (MIRI). Our study investigates its underlying mechanism through regulation of pyroptosis.

METHODS

To understand the role of β-sitosterol in protecting cardiomyocytes, MIRI rats were treated with β-sitosterol. Rats' cardiac functions were monitored, and hearts were harvested for histology and Western Blot analysis. Immunofluorescence, immunoblot, enzyme-linked immunosorbent assay, as well as overexpression and knockdown techniques were utilized in this study to investigate the molecular mechanisms underlying the cardioprotective effects of β-sitosterol.

RESULTS

Our results showed that β-Sitosterol significantly reduced H/R-induced pyroptosis in cardiomyocytes by decreasing cleaved caspase-1, gasdermin D (GSDMD), interleukin-1β (IL-1β), and interleukin-18 (IL-18). Immunofluorescence staining confirmed suppression of NLRP3 inflammasome activation. Notably, β-Sitosterol inhibited pyroptosis induced by ATP and ATP/LPS through the regulation of PPARγ2. Moreover, PPARγ2 upregulation promoted ATP and ATP/LPS-induced pyroptosis through the NLRP3/caspase-1/GSDMD pathway. In vivo, β-sitosterol alleviates myocardial ischemia-reperfusion injury-induced cardiac dysfunction and myocardial fibrosis in rats.

CONCLUSIONS

These findings provide new evidence supporting β-sitosterol as a potential therapeutic agent for cardiovascular diseases involving ischemic injury. Its protective effects may be mediated through targeting PPARγ2 and modulating NLRP3-dependent pyroptosis.

Programmed cardiomyocyte death in myocardial infarction

Cardiovascular disease (CVD) is a leading cause of human mortality worldwide, with patients often at high risk of heart failure (HF) in myocardial infarction (MI), a common form of CVD that results in cardiomyocyte death and myocardial necrosis due to inadequate myocardial perfusion. As terminally differentiated cells, cardiomyocytes possess a severely limited capacity for regeneration, and an excess of dead cardiomyocytes will further stress surviving cells, potentially exacerbating to more extensive heart disease. The article focuses on the relationship between programmed cell death (PCD) of cardiomyocytes, including different forms of apoptosis, necrosis, and autophagy, and MI, as well as the potential application of these mechanisms in the treatment of MI. By gaining a deeper understanding of the mechanisms of cardiomyocyte death, it aims to provide new insights into the prevention and treatment of MI.

Chromofungin mitigates free fatty acids-induced endothelial inflammation via inhibition of NOD-like receptor thermal protein domain-associated protein 3 mediated by adenosine 5'-monophosphate-activated protein kinase

Free fatty acids (FFAs) have emerged as significant risk factors for atherosclerosis (AS). Prolonged exposure to FFAs induces vascular endothelial injury, including inflammatory responses and oxidative stress, which are central events in AS. Chromofungin (CHR), a peptide derived from chromogranin A (CGA), has been implicated in various biological functions. However, its physiological roles in endothelial biology and its involvement in the pathological development of AS have not been previously reported. In the present study, we investigated the underlying mechanisms through which CHR exerts its beneficial effects on FFA-challenged human aortic endothelial cells (HAECs). We found that treatment with CHR ameliorated the FFA-induced reduction in cell viability and increase in lactate dehydrogenase (LDH) release. Additionally, CHR mitigated oxidative stress by reducing mitochondrial reactive oxygen species (ROS) levels and increasing superoxide dismutase (SOD) activity. Furthermore, exposure to FFAs increased NADPH oxidase (NOX) 4 expression at both the mRNA and protein levels, which were attenuated by CHR in a dose-dependent manner. Notably, CHR reduced the levels of nucleotide-binding domain and leucine-rich repeat-containing (NLR) family pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), and cleaved caspase-1 (p10), key components of the NLRP3 inflammasome complex, as well as interleukin 1β (IL-1β) and interleukin-18 (IL-18) expression. Mechanistically, it was demonstrated that FFAs reduced the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC), which were rescued by CHR in a dose-dependent manner. Conversely, inhibition of AMPK with its specific inhibitor compound C abolished the protective effects of CHR against FFA-induced activation of the NLRP3 inflammasome in HAECs. Based on these findings, we conclude that CHR may serve as a promising agent for maintaining normal endothelial cell function and treating AS.

Different types of cell death and their interactions in myocardial ischemia-reperfusion injury

Myocardial ischemia-reperfusion (I/R) injury is a multifaceted process observed in patients with coronary artery disease when blood flow is restored to the heart tissue following ischemia-induced damage. Cardiomyocyte cell death, particularly through apoptosis, necroptosis, autophagy, pyroptosis, and ferroptosis, is pivotal in myocardial I/R injury. Preventing cell death during the process of I/R is vital for improving ischemic cardiomyopathy. These multiple forms of cell death can occur simultaneously, interact with each other, and contribute to the complexity of myocardial I/R injury. In this review, we aim to provide a comprehensive summary of the key molecular mechanisms and regulatory patterns involved in these five types of cell death in myocardial I/R injury. We will also discuss the crosstalk and intricate interactions among these mechanisms, highlighting the interplay between different types of cell death. Furthermore, we will explore specific molecules or targets that participate in different cell death pathways and elucidate their mechanisms of action. It is important to note that manipulating the molecules or targets involved in distinct cell death processes may have a significant impact on reducing myocardial I/R injury. By enhancing researchers' understanding of the mechanisms and interactions among different types of cell death in myocardial I/R injury, this review aims to pave the way for the development of novel interventions for cardio-protection in patients affected by myocardial I/R injury.

Identification and functional analysis of energy metabolism and pyroptosis-related genes in diabetic nephropathy

Background

Energy metabolism and pyroptosis are integral to the pathogenesis of diabetic nephropathy (DN). However, the precise roles of energy metabolism and pyroptosis in DN development remain unclear. This study aims to elucidate the roles of energy metabolism- and pyroptosis-related differentially expressed genes (EMAPRDEGs) in DN development.

Methods

EMAPRDEGs were identified by querying the GeneCards and Gene Expression Omnibus (GEO) databases. Subsequent analyses included Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, Gene Set Enrichment Analysis (GSEA), and Protein-Protein Interaction (PPI) network analysis. Additionally, mRNA-miRNA, mRNA-drug, and mRNA-transcription factor (TF) interaction networks were constructed. Differential expression and receiver operating characteristic (ROC) curve analyses were performed to evaluate the diagnostic potential of EMAPRDEGs. Immune cell infiltration in DN was assessed using the ssGSEA algorithm, and the expression levels of EMAPRDEGs in DN tissues were validated by quantitative real-time PCR (qRT-PCR).

Results

Thirteen EMAPRDEGs were identified, with GO and KEGG analyses indicating their involvement in energy metabolism pathways. GSEA revealed significant enrichment of these genes in biological pathways associated with diabetic nephropathy. PPI network analysis highlighted the central role of these genes within the relevant pathways. Predictive modeling demonstrated interactions between EMAPRDEGs, 69 miRNAs, and 117 TFs. Immune infiltration analysis showed substantial alterations in immune cell populations, with ADH1B and PC showing a significant correlation with natural killer cells and memory B cells. ROC curve analysis confirmed the diagnostic potential of EMAPRDEGs for diabetic nephropathy. qRT-PCR validated the expression patterns of CASP1, IL-18, PDK4, and FBP1, which were consistent with the bioinformatics predictions.

Conclusion

Bioinformatics analysis identified 13 candidate EMAPRDEGs, among which CASP1, IL-18, PDK4, and FBP1 emerge as potential biomarkers for diabetic nephropathy.

Unlocking the Therapeutic Potential of Natural Products for Alzheimer's Disease

Alzheimer's disease (AD) is a progressive neurodegenerative condition marked by memory loss and cognitive decline. With current treatments offering limited effectiveness, researchers are turning to natural products that can target various aspects of AD pathology. Clinically approved natural products, such as galantamine and huperzine A, have shown success in AD treatments. Furthermore, compounds such as epigallocatechin gallate, quercetin, and resveratrol are in clinical trials. This Perspective examines nearly 100 natural compounds with promising neuroprotective effects in preclinical and clinical studies. These compounds exhibit diverse pharmacological actions that help to prevent neurodegeneration while improving cognitive functions. Their unique structures further enhance their biological activities, making them promising candidates for drug discovery. This Perspective stresses the importance of further clinical research to maximize the medical benefits of these compounds and highlights their potential as innovative remedies for AD. Continued exploration of these compounds is crucial to fully leverage their capabilities in combating AD.

Peptide amphiphiles alleviate myocardial endoplasmic reticulum stress to enhance cardiomyocyte-macrophage communication and promote macrophage M2 polarization

Myocardial ischemia-reperfusion (I/R) injury represents a significant clinical challenge with limited therapeutic options. Single-cell RNA sequencing and bioinformatics analyses have revealed complex cellular interactions within cardiac tissue, highlighting the crucial role of cardiomyocytes in intercellular communication. During I/R injury, cardiomyocytes experience severe endoplasmic reticulum (ER) stress, leading to detrimental intercellular communication that affects surrounding cells, particularly promoting the transformation of macrophages toward a pro-inflammatory phenotype. This amplifies the inflammatory cascade and exacerbates tissue damage. Targeting injured cardiomyocytes and inhibiting their ER stress presents a promising therapeutic strategy to restore beneficial intercellular communication and maintain myocardial homeostasis, thereby reducing I/R injury. However, the lack of an effective ER stress inhibitor specifically targeting damaged cardiomyocytes constitutes a major barrier to translating mechanistic understanding into therapeutic implementation. Peptide amphiphiles (PA), with their unique amphiphilicity and bioactive functions, constitute ideal candidates for targeted drug delivery. In this study, we developed a cascade-responsive drug delivery system, CT-PA@Sal, which selectively targets damaged cardiomyocytes and controls the release of the ER stress inhibitor Salubrinal. CT-PA@Sal demonstrates superior targeting efficiency and enhanced drug bioavailability, enabling responsive release within injured cardiomyocytes. In vitro and in vivo experiments further show that CT-PA@Sal improves cardiomyocyte-macrophage communication, reduces cardiomyocyte apoptosis, and promotes anti-inflammatory M2 macrophage polarization. These effects preserve cardiac function and enhance tissue recovery following I/R injury. We envision that this investigation offers a prospective framework for developing targeted drugs to treat myocardial I/R injury.

TRIM44 alleviates renal ischemia-reperfusion injury by inhibiting pyroptosis through the NLRP3 pathway

BACKGROUND

Renal ischemia-reperfusion injury (IRI) is a prevailing manifestation of acute kidney injury (AKI) with limited treatment options. TRIM44 has emerged as a possible target for treatment due to its regulatory function in inflammatory pathways.

METHODS

In vivo and in vitro models were employed to ascertain the TRIM44 impact on renal IRI. In vivo, we induced IRI in mice and assessed histological changes, oxidative stress markers, and pyroptosis-related proteins. In vitro, we subjected renal cells to hypoxia/reoxygenation (H/R) and manipulated TRIM44 expression to evaluate its effects on cell viability and pyroptosis.

RESULTS

IRI significantly increased inflammation, oxidative stress, and pyroptosis in both animal and cell models, evidenced by elevated cleaved caspase-1, GSDMD-N, and IL-1β/-18 levels. IRI conditions experienced a mitigated TRIM44 expression. Overexpression of TRIM44 in renal cells reduced pyroptosis, as shown by decreased levels of pyroptosis-related proteins and inflammatory cytokines and improved cell viability. Mechanistically, TRIM44 inhibited the NLRP3 inflammasome, as evidenced with reduced NLRP3 and cleaved caspase-1 levels upon TRIM44 overexpression and NLRP3 inhibition. In vivo, intravenous administration of TRIM44-expressing adenovirus post-IRI ameliorated renal damage, as reported with mitigated serum creatinine and blood urea nitrogen levels.

CONCLUSION

TRIM44 protects against renal IRI by inhibiting pyroptosis via the NLRP3 pathway, suggesting its potential to be targeted therapeutically for treating AKI.

Therapeutic Potential of Gasdermin D-Mediated Myocardial Pyroptosis in Ischaemic Heart Disease: Expanding the Paradigm From Bench to Clinical Insights

Ischaemic heart disease (IHD) remains a leading cause of global morbidity and mortality. One significant contributor to the pathology of IHD is the excessive release of inflammatory mediators during the disease progression. Pyroptosis is a form of programmed cell death (PCD) triggered by the activation of inflammasomes and caspase 1. The activation of inflammatory caspase 1 proteolytically cleaves gasdermin D (GSDMD) to the activated form amino acid terminus (GSDMD-NT), leading to disruption of the plasma membrane. This cascade of events is considered the canonical pathway of pyroptosis. IHD also caused oxidative stress, thereby triggering noncanonical pyroptosis via the activation of caspases 4/5/11. Previous studies have provided compelling evidence of the close relationship between pyroptosis and the aetiology of IHD (e.g., acute myocardial infarction, myocardial ischaemia and reperfusion injury and chronic myocardial infarction), as well as the association of pyroptosis with unfavourable clinical outcomes. Several interventions aimed at targeting pyroptosis have demonstrated promising therapeutic benefits against IHD-related pathologies. This review provides mechanistic insights into the roles of pyroptosis in IHD from in vitro, in vivo and clinical perspectives. In-depth understanding into this area could also pave the way for the future development of novel therapeutic strategies targeting pyroptosis in IHD.

Identification of VDAC1 as a cardioprotective target of Ginkgolide B

Ginkgolide B (GB), a compound derived from Ginkgo biloba, exhibits significant cardioprotective properties, although its precise molecular target has yet to be identified. In this study, we synthesized a biotin-labeled GB probe (GB-biotin) to identify the molecular targets of GB. Our experiments demonstrated that treatment with GB or GB-biotin reduced mitochondrial injury, restored mitochondrial membrane potential, and decreased cell apoptosis in a concentration-dependent manner. Additionally, GB increased mitochondrial oxygen consumption rate, indicating improved mitochondrial bioenergetics. Proteomic analysis revealed that the voltage-dependent anion channel 1 (VDAC1) is a key protein that interacts with GB-biotin. This finding was further confirmed through cellular thermal shift assay (CETSA) and molecular docking, which revealed hydrogen bond formation between GB and VDAC1. Furthermore, overexpression of VDAC1 diminished the protective effects of GB, highlighting the crucial role of VDAC1 in GB-mediated cardioprotection. These findings identify VDAC1 as a therapeutic target for GB in vitro, providing valuable insights into the cardioprotective mechanisms of GB and the development of novel cardioprotective strategies.

Active ingredients of traditional Chinese medicine inhibit NOD-like receptor protein 3 inflammasome: a novel strategy for preventing and treating heart failure

Heart failure (HF) has emerged as a significant global public health challenge owing to its high rates of morbidity and mortality. Activation of the NOD-like receptor protein 3 (NLRP3) inflammasome is regarded as a pivotal factor in the onset and progression of HF. Therefore, inhibiting the activation of the NLRP3 inflammasome may represent a promising therapeutic approach for preventing and treating HF. The active ingredients serve as the foundation for the therapeutic effects of traditional Chinese medicine (TCM). Recent research has revealed significant advantages of TCM active ingredients in inhibiting the activation of the NLRP3 inflammasome and enhancing cardiac structure and function in HF. The study aimed to explore the impact of NLRP3 inflammasome activation on the onset and progression of HF, and to review the current advancements in utilizing TCM active ingredients to inhibit the NLRP3 inflammasome for preventing and treating HF. This provides a novel perspective for the future development of precise intervention strategies targeting the NLRP3 inflammasome to prevent and treat HF.

Progress in Chinese medicine monomers and their nanoformulations on myocardial ischemia/reperfusion injury

Myocardial ischemia/reperfusion injury (MIRI) is the entire process of myocardial injury resulting from ischemia and hypoxia following acute myocardial infarction, which involves complicated pathogenesis including energy metabolism disorders, calcium overload, oxidative stress and mitochondrial dysfunction. Traditional Chinese medicine (TCM) has attracted intensive attention in the treatment of MIRI owing to its multitarget therapeutic effects and low systemic toxicity. Increasing evidence indicates the promising application of TCM on the protection of cardiomyocytes, improvement of endothelial cell functions and regulation of energy metabolism and inflammatory response. Although the efficacy of TCM has been well-proven, the underlying mechanisms remain unclear. Additionally, the clinical application of much TCM had been hampered due to its low aqueous solubility, poor gastrointestinal absorption, and decreased bioavailability. In this review, we examined the pathological mechanism of MIRI and highlighted recent research studies on the therapeutic effects and molecular mechanisms of monomer compounds derived from TCM. We also summarized the latest studies in nanoformulation-based strategies for improving the targeting and stability of TCM monomers and exerting synergistic effects. The aim of this study was to provide a scientific basis for the treatment of MIRI with TCM monomers combined with nanomaterials, revealing their clinical significance and development prospects.

HMGB1 lactylation drives neutrophil extracellular trap formation in lactate-induced acute kidney injury

Rationale

Acute kidney injury (AKI) is a clinical syndrome associated with a multitude of conditions. Although renal replacement therapy (RRT) remains the cornerstone of treatment for advanced AKI, its implementation can potentially pose risks and may not be readily accessible across all healthcare settings and regions. Elevated lactate levels are implicated in sepsis-induced AKI; however, it remains unclear whether increased lactate directly induces AKI or elucidates the underlying mechanisms.

Methods

For human, the measurement of lactate in arterial blood gas is performed using the direct determination of L-lactate through an electrode oxidation method by a blood gas analyzer. For mice, enzyme-linked immunosorbent assay (ELISA) kits were employed to quantify the concentrations of lactate and AKI biomarkers in blood and cell supernatant. The mouse model of AKI was performed with a single intraperitoneal (i.p.) administration of lactate (30 mg/kg) and low-dose LPS (2 mg/kg) for 24 h. Proteomic analysis was conducted to identify lactylated proteins in kidney tissues. Techniques such as, immunoprecipitation, western blotting and immunofluorescence were used to evaluate the levels of HMGB1 lactylation, neutrophil extracellular traps (NETs)and to assess related molecular signaling pathways.

Main results

Our findings indicate that lactate serves as an independent predictor of AKI in patients with acute decompensated heart failure (ADHF). We observed that co-administration of lactate with low-dose lipopolysaccharide (LPS) resulted in lactate overproduction, which subsequently elevated serum levels of creatinine (Cre) and blood urea nitrogen (BUN). Furthermore, the combined application of lactate and low-dose LPS was shown to provoke HMGB1 lactylation within renal tissues. Notably, pretreatment with HMGB1 small interfering RNA (siRNA) effectively diminished lactate-mediated HMGB1 lactylation and alleviated the severity of AKI. Additionally, lactate accumulation was found to enhance the expression levels of NETs in the bloodstream, with circulating NETs levels positively correlating with HMGB1 lactylation. Importantly, pre-administration of HMGB1 inhibitors (glycyrrhizin) or lactate dehydrogenase A (LDH-A) inhibitors (oxamate) reversed the upregulation of NETs induced by lactate and low-dose LPS in both the blood and polymorphonuclear neutrophils (PMNs) cell supernatant, thereby ameliorating AKI associated with lactate accumulation.

Conclusions

These findings illuminate the role of lactate-mediated HMGB1 lactylation in inducing AKI in mice through the activation of the HMGB1-NETs signaling pathway.

Deciphering Oxidative Stress in Cardiovascular Disease Progression: A Blueprint for Mechanistic Understanding and Therapeutic Innovation

Oxidative stress plays a pivotal role in the pathogenesis and progression of cardiovascular diseases (CVDs). This review focuses on the signaling pathways of oxidative stress during the development of CVDs, delving into the molecular regulatory networks underlying oxidative stress in various disease stages, particularly apoptosis, inflammation, fibrosis, and metabolic imbalance. By examining the dual roles of oxidative stress and the influences of sex differences on oxidative stress levels and cardiovascular disease susceptibility, this study offers a comprehensive understanding of the pathogenesis of cardiovascular diseases. The study integrates key findings from current research in three comprehensive ways. First, it outlines the major CVDs associated with oxidative stress and their respective signaling pathways, emphasizing oxidative stress's central role in cardiovascular pathology. Second, it summarizes the cardiovascular protective effects, mechanisms of action, and animal models of various antioxidants, offering insights into future drug development. Third, it discusses the applications, advantages, limitations, and potential molecular targets of gene therapy in CVDs, providing a foundation for novel therapeutic strategies. These tables underscore the systematic and integrative nature of this study while offering a theoretical basis for precision treatment for CVDs. A major contribution of this study is the systematic review of the differential effects of oxidative stress across different stages of CVDs, in addition to the proposal of innovative, multi-level intervention strategies, which open new avenues for precision treatment of the cardiovascular system.

Construction of AMPK-related circRNA network in mouse myocardial ischemia-reperfusion injury model

OBJECTIVE

To screen Myocardial ischemia-reperfusion Injury in mice. adenosine monophate-activatedprotein kinase (AMPK) -related differentially expressed circularRNA (circRNA) in MIRI model, Ampk-related circRNA network was drawn to provide possible ideas for the prevention and treatment of MIRI.

METHODS

The mouse MIRI model was constructed by ligation of the left anterior descending artery. After the model was successfully established, the related indicators of cardiac function were detected, and high-throughput sequencing was performed on the myocardial tissue of the mice.

RESULTS

MIRI model was successfully constructed, and two AMPK related differentially expressed loops (novel_circ_043550 and novel_circ_035243) were screened out. A circRNA-miRNA-mRNA network consisting of 2 circRNA, 28 microRNA(miRNA) and 229 messengerRNA (mRNA) was constructed.

CONCLUSIONS

This study reveals the differential expression of several AMPK-related circRNAs in MIRI in mice, and the AMPK-related circRNA regulatory network is constructed, suggesting that AMPK-related circRNA may have potential clinical application prospects as a potential molecular marker and therapeutic target for MIRI.

Identification of Diagnostically Relevant Biomarkers in Patients with Coronary Artery Disease by Comprehensive Analysis

Background

Peripheral biomarkers are becoming an important method by which to monitor the progression of coronary artery disease (CAD). Not only are they minimally invasive and early detection, but they can also be used for classification and diagnosis of disease as well as prognostic assessment. Currently, this approach is still in the exploratory stage. The purpose of this research is to determine the diagnostic value and therapeutic potential of the endoplasmic reticulum stress (ERS) genes in CAD.

Methods

The clinical information and RNA sequence data were obtained from the GEO database and subsequently subjected to a series of optimization and visualization processes using various analytical techniques, including WGCNA, LASSO, SVM-RFE feature selection, random forest (RF), and XGBoost, as well as R software and Cytoscape. Finally, immunofluorescence was used to validate the analysis.

Results

We identify 6 key ERS differentially expressed genes (ERS-DEGs) (UFL1, HSPA1A, ERLIN1, LRRK2, ERN1, SERINC3) for constructing diagnostic models. They showed qualified diagnostic ability as biomarkers of CAD within training dataset (AUC = 0.803) and validation dataset (AUC = 0.776 and 0.797). Association analyses showed that peripheral immune cells, immune checkpoint genes and Human Leukocyte Antigen (HLA) genes had characteristic distributions in CAD and were closely related to specific ERS genes. Meanwhile, we found that HSPA1A may involve the MAPK signaling pathway in CAD.

Conclusion

We constructed an efficient diagnostic model based on 6 key ERS-DEGs and explored their regulatory networks and effects on the CAD immune microenvironment. UFL1, HSPA1A, ERLIN1, LRRK2, ERN1, SERINC3 are expected to be biomarkers for CAD.

Tyrobp deficiency blocks NLRP3-mediated inflammation and pyroptosis to alleviate myocardial ischemia-reperfusion injury through regulating Syk

PURPOSE

The present study aims to investigate the biological function of Tyrobp in myocardial ischemia-reperfusion injury (MIRI) and to clarify its potential reaction mechanisms.

METHODS

AC16 cells were induced by oxygen-glucose deprivation/reoxygenation (OGD/R) to simulate the MIRI in vitro. The cell transfection technology was used to downregulate Tyrobp, followed by assessment of cell damage, apoptosis and cytokines production via Cell Counting Kit (CCK)-8 assay, lactate dehydrogenase (LDH) release assay, TUNEL and ELISA assays, respectively. Immunofluorescence assay was performed to assess GSDMD. Corresponding proteins were detected via western blotting, and Co-immunoprecipitation (Co-IP) assay was used to validate proteins interaction.

RESULTS

Tyrobp was upregulated in OGD/R-exposed AC16 cells, and Tyrobp deficiency significantly alleviated OGD/R-caused cell viability loss, LDH release and cell apoptosis in AC16 cells. Meanwhile, Tyrobp deficiency inhibited the activation of NLRP3 inflammasome, reduced the production of cytokines and inhibited GSDMD intensity and GSDMD-N expression. Additionally, Tyrobp could interact with Syk and regulate Syk/NF-κB signaling. The rescue experiments showed that the above effects of Tyrobp deficiency on OGD/R-exposed AC16 cells were partly weakened by Syk overexpression.

CONCLUSION

Tyrobp deficiency alleviated MIRI by inhibiting NLRP3-mediated inflammation and pyroptosis through regulating Syk, providing a novel target for the treatment of MIRI.

Moderate-intensity aerobic exercise inhibits cell pyroptosis to improve myocardial ischemia-reperfusion injury

BACKGROUND

Myocardial ischemia-reperfusion injury (MI/RI) significantly impacts the patients with acute myocardial infarction (AMI), with the NLRP3-mediated necrosis exacerbates the pathological progression of myocardial infarction. Exercise, recognized as a crucial approach for both disease prevention and treatment, is widely utilized in clinical practice worldwide and has demonstrated broad effectiveness in cardiovascular disease (CVD) prevention.

PURPOSE

To explore the cardio protective effect of exercise preconditioning and the mechanism by which exercise modulation of NLRP3 improves myocardial ischemia and reperfusion injury.

METHODS AND RESULTS

In this study, C57BL/6 N mice were employed to establish an exercise preconditioning model and a MI/RI model. The exercise intervention involved moderate-intensity aerobic exercise on a treadmill (50-70% VO2max) for small animals. Our research findings indicate that moderate-intensity aerobic exercise intervention improved cardiac function, reduced myocardial injury and inflammatory response, decreased myocardial infarction area and degree of cell apoptosis in mice compared to those raised under conventional conditions. Additionally, the expression of NLRP3 in the myocardial tissue of mice with MI/RI was reduced after exercise intervention. Moreover, exercise inhibited the activation of apoptosis related proteins such as Caspase-1 and GSDMD, while reducing the levels of inflammatory factors such as IL-1β and IL-18.

CONCLUSIONS

This study found that moderate-intensity aerobic exercise can reduce the inflammatory response, reduce the degree of cell pyroptosis, reduce myocardial ischemia and reperfusion injury, and achieve endogenous protective effects on the myocardium.

Bone Morphogenetic Protein 9 Protects Against Myocardial Infarction by Improving Lymphatic Drainage Function and Triggering DECR1-Mediated Mitochondrial Bioenergetics

BACKGROUND

BMP9 (bone morphogenetic protein 9) is a member of the TGF-β (transforming growth factor β) family of cytokines with pleiotropic effects on glucose metabolism, fibrosis, and lymphatic development. However, the role of BMP9 in myocardial infarction (MI) remains elusive.

METHODS

The expressional profiles of BMP9 in cardiac tissues and plasma samples of subjects with MI were determined by immunoassay or immunoblot. The role of BMP9 in MI was determined by evaluating the impact of BMP9 deficiency and replenishment with adeno-associated virus-mediated BMP9 expression or recombinant human BMP9 protein in mice.

RESULTS

We show that circulating BMP9 and its cardiac levels are markedly increased in humans and mice with MI and are negatively associated with cardiac function. It is important to note that BMP9 deficiency exacerbates left ventricular dysfunction, increases infarct size, and augments cardiac fibrosis in mice with MI. In contrast, replenishment of BMP9 significantly attenuates these adverse effects. We further demonstrate that BMP9 improves lymphatic drainage function, thereby leading to a decrease of cardiac edema. In addition, BMP9 increases the expression of mitochondrial DECR1 (2,4-dienoyl-CoA [coenzyme A] reductase 1), a rate-limiting enzyme involved in β-oxidation, which, in turn, promotes cardiac mitochondrial bioenergetics and mitigates MI-induced cardiomyocyte injury. Moreover, DECR1 deficiency exacerbates MI-induced cardiac damage in mice, whereas this adverse effect is restored by the treatment of adeno-associated virus-mediated DECR1. Consistently, DECR1 deletion abrogates the beneficial effect of BMP9 against MI-induced cardiomyopathy and cardiac damage in mice.

CONCLUSIONS

These results suggest that BMP9 protects against MI by fine-tuning the multiorgan cross-talk among the liver, lymph, and the heart.

(Pro)renin receptor aggravates myocardial pyroptosis in diabetic cardiomyopathy through AMPK-NLRP3 pathway

Introduction

As one of the most common complications of diabetes, diabetic cardiomyopathy (DCM) is the main cause of heart failure in patients with diabetes. However, the lack of effective treatments for DCM remains a clinical challenge. (Pro) renin receptor (PRR) is a member of renin angiotensin aldosterone system (RAAS). Here, we aim to determine whether PRR is involved in myocardial pyroptosis in diabetic cardiomyopathy.

Methods

We established diabetic rats model by intraperitoneal injection of streptozotocin (STZ). PRR overexpression adenovirus or PRR knockdown adenovirus was injected into the tail vein. Western blot, histopathology and immunohistochemistry staining, ELISA and Echocardiography were used to detect cardiac function changes and myocardial injury levels of DCM rats. Primary cardiomyocytes were stimulated with high glucose and PRR overexpression or PRR knockdown was achieved by adenovirus transfection, we also used the inhibitor of AMPK to decrease the activity of AMPK. Western blot, Real-time PCR, Immunofluorescence and ELISA were used to detect the level of PRR and pyroptosis in cardiomyocyte.

Results

We found that high glucose increased the expression of PRR in heart. After overexpression of PRR, the expression of the pyroptosis related proteins such as Caspase-1, IL-1β, IL-18, and NLRP3 was significantly increased, the phosphorylation level of AMPK was significantly decreased, and the fibrosis level was significantly increased, thus aggravating the cardiac function injury of DCM. On the contrary, PRR knockdown can alleviate the level of myocardial pyroptosis in DCM and improve cardiac function. The related mechanism was that PRR could inhibit AMPK phosphorylation and promote the activation of NLRP3 inflammasome.

Discussion

PRR aggravated pyroptosis of cardiomyocyte, increased the dysfunction of cardiomyocyte, and may be related to the decrease of AMPK phosphorylation and the overactivation of NLRP3. This may provide new ideas and targets for the treatment of DCM.

Myocardial ischemia-reperfusion injury: The balance mechanism between mitophagy and NLRP3 inflammasome

Myocardial ischemia-reperfusion injury (MIRI) is an injury to cardiomyocytes due to restoration of blood flow after myocardial infarction (MI). It has recently gained much attention in clinical research with special emphasis on the roles of mitochondrial autophagy and inflammation. A mild inflammatory response promotes recovery of post-ischemic cardiomyocyte function and vascular regeneration, but a severe inflammatory response can cause irreversible and substantial cellular damage. Similarly, moderate mitochondrial autophagy can help inhibit excessive inflammation and protect cardiomyocytes. However, MIRI is aggravated when mitochondrial function is disrupted, such as inadequate clearance of damaged mitochondria or excessive activation of mitophagy. How to moderately control mitochondrial autophagy while promoting its balance with nucleotide-binding oligomerization structural domain receptor protein 3 (NLRP3) inflammasome activation is critical. In this paper, we reviewed the molecular mechanisms of mitochondrial autophagy and NLRP3 inflammasome, described the interaction between NLRP3 inflammasome and mitochondrial autophagy, and the effects of different signaling pathways and molecular proteins on MIRI, to provide a reference for future research.

Disruption of BACH1 Protects AC16 Cardiomyocytes Against Hypoxia/Reoxygenation-Evoked Injury by Diminishing CDKN3 Transcription

Reperfusion after myocardial infarction (MI) can lead to myocardial ischemia/reperfusion (I/R) damage. The transcription factor (TF) broad-complex, tramtrack, and bric-a-brac (BTB) and cap'n'collar (CNC) homology 1 (BACH1) is implicated in the injury. However, the downstream mechanisms of BACH1 in affecting myocardial hypoxia/reoxygenation (H/R) damage are still fully understood. AC16 cells were stimulated with H/R conditions to model cardiomyocytes under H/R. mRNA analysis was performed by quantitative real-time PCR. Protein levels were gauged by immunoblot analysis. The effect of BACH1/cyclin-dependent kinase inhibitor 3 (CDKN3) on H/R-evoked injury was assessed by measuring cell viability via Cell Counting Kit-8 (CCK-8), apoptosis (flow cytometry and caspase 3 activity), ferroptosis via Fe2+, glutathione (GSH), reactive oxygen species (ROS) and malondialdehyde (MDA) markers and inflammation cytokines interleukin-1beta (IL-1β) and tumor necrosis factor alpha (TNF-α). The BACH1/CDKN3 relationship was examined by chromatin immunoprecipitation (ChIP) experiment and luciferase assay. BACH1 was increased in MI serum and H/R-stimulated AC16 cardiomyocytes. Functionally, disruption of BACH1 mitigated H/R-evoked in vitro apoptosis, ferroptosis and inflammation of AC16 cardiomyocytes. Mechanistically, BACH1 activated CDKN3 transcription and enhanced CDKN3 protein expression in AC16 cardiomyocytes. Our rescue experiments validated that BACH1 disruption attenuated H/R-evoked AC16 cardiomyocyte apoptosis, ferroptosis and inflammation by downregulating CDKN3. Additionally, BACH1 disruption could activate the adenosine monophosphate-activated protein kinase (AMPK) signaling by downregulating CDKN3 in H/R-stimulated AC16 cardiomyocytes. Our study demonstrates that BACH1 activates CDKN3 transcription to induce H/R-evoked damage of AC16 cardiomyocytes partially via AMPK signaling.

TRPC6 regulates necroptosis in myocardial ischemia/reperfusion injury via Ca2+/CaMKII signaling pathway

Myocardial ischemia-reperfusion injury (MIRI) frequently complicates postoperative cardiovascular disease treatment. Necroptosis, a cell death mechanism similar to apoptosis, is regulated by specific signaling pathways and plays an important role in MIRI. Receptor-interacting protein 3 (RIP3), a key protein regulating necroptosis during MIRI, directly phosphorylates calmodulin-dependent protein kinase II (CaMKII). Leading to mitochondrial permeablity transition pore (mPTP) opening and inducing necroptosis. Transient receptor potential canonical channel 6 (TRPC6) regulats Ca2+ entry, is linked to CaMKII as an important upstream effector. However, the connection between TRPC6 and MIRI necroptosis remains unclear. The study aimed to investigate the relationship between TRPC6 and MIRI necroptosis, with a specific focus on elucidating the role of TRPC6 in regulating CaMKII phosphorylation during cardiac necroptosis via Ca2+ modulation. METHODS AND RESULTS: The experiment used wild-type (WT) and TRPC6 knockout (TRPC6-/-) mice for I/R model construction, and H9c2 myocardial cell line for H/R model. After ischemia-reperfusion (I/R), TRPC6 protein levels in mice significantly increased, exacerbating myocardial injury, infarct size (IS), and cardiac function in WT mice. In contrast, TRPC6 knockout attenuated myocardial injury, IS, and improved cardiac function. The results showed a significant correlation between changes in CaMKII and TRPC6. TRPC6 knockout led to decreased intracellular calcium levels, CaMKII phosphorylation, reactive oxygen species levels, mPTP opening, and improve mitochondrial structure. CONCLUSION: I/R upregulates TRPC6, which mediates Ca2+ entry and CaMKII phosphorylation, exacerbates oxidative stress, and induces necroptosis. These findings suggest a potential therapeutic avenue for mitigating MIRI by targeting TRPC6.

Pyroptosis in health and disease: mechanisms, regulation and clinical perspective

Pyroptosis is a type of programmed cell death characterized by cell swelling and osmotic lysis, resulting in cytomembrane rupture and release of immunostimulatory components, which play a role in several pathological processes. Significant cellular responses to various stimuli involve the formation of inflammasomes, maturation of inflammatory caspases, and caspase-mediated cleavage of gasdermin. The function of pyroptosis in disease is complex but not a simple angelic or demonic role. While inflammatory diseases such as sepsis are associated with uncontrollable pyroptosis, the potent immune response induced by pyroptosis can be exploited as a therapeutic target for anti-tumor therapy. Thus, a comprehensive review of the role of pyroptosis in disease is crucial for further research and clinical translation from bench to bedside. In this review, we summarize the recent advancements in understanding the role of pyroptosis in disease, covering the related development history, molecular mechanisms including canonical, non-canonical, caspase 3/8, and granzyme-mediated pathways, and its regulatory function in health and multiple diseases. Moreover, this review also provides updates on promising therapeutic strategies by applying novel small molecule inhibitors and traditional medicines to regulate pyroptosis. The present dilemmas and future directions in the landscape of pyroptosis are also discussed from a clinical perspective, providing clues for scientists to develop novel drugs targeting pyroptosis.

Streptococcus suis Induces Macrophage M1 Polarization and Pyroptosis

Streptococcus suis is an important bacterial pathogen that affects the global pig industry. The immunosuppressive nature of S. suis infection is recognized, and our previous research has confirmed thymus atrophy with a large number of necrotic cells. In this current work, we aimed to uncover the role of pyroptosis in cellular necrosis in thymic cells of S. suis-infected mice. Confocal microscopy revealed that S. suis activated the M1 phenotype and primed pyroptosis in the macrophages of atrophied thymus. Live cell imaging further confirmed that S. suis could induce porcine alveolar macrophage (PAM) pyroptosis in vitro, displaying cell swelling and forming large bubbles on the plasma membrane. Meanwhile, the levels of p-p38, p-extracellular signal-regulated kinase (ERK) and protein kinase B (AKT) were increased, which indicated the mitogen-activated protein kinase (MAPK) and AKT pathways were also involved in the inflammation of S. suis-infected PAMs. Furthermore, RT-PCR revealed significant mRNA expression of pro-inflammatory mediators, including interleukin (IL)-1β, IL-6, IL-18, tumor necrosis factor (TNF)-α and chemokine CXCL8. The data indicated that the inflammation induced by S. suis was in parallel with pro-inflammatory activities of M1 macrophages, pyroptosis and MAPK and AKT pathways. Pyroptosis contributes to necrotic cells and thymocyte reduction in the atrophied thymus of mice.

Ginsenoside RD prevents acute liver injury in mice by inhibiting STAT3-mediated NLRP3/GSDMD activation

We investigated the role and mechanism of ginsenoside RD (GRD) in acute liver injury. Network pharmacology was used to analyze the correlations among GRD-liver injury-pyroptosis targets. A mouse model of acute liver injury was established by lipopolysaccharide + d-galactose（LPS + d/Gal). After pretreatment with GRD, the changes in mouse liver function were detected. The histopathological changes were assayed by hematoxylin and eosin and Masson staining, the tissue expressions of inflammatory cytokines were detected by enzyme-linked immunosorbent assay, and the protein expressions were assayed by immunohistochemical staining and Western blotting. Meanwhile, mechanism research was conducted using STAT3-knockout transgenic mice and STAT3-IN13, a STAT3 inhibitor. GRD inhibited liver injury, mitigated tissue inflammation, and suppressed STAT3-mediated pyroptosis in mice. After applying STAT3-knockout mouse model or STAT3-IN13, GRD did not further inhibit the liver injury. GRD can resist liver injury by inhibiting the STAT3-mediated pyroptosis, which is one of the hepatoprotective mechanisms of GRD.

Geniposide for treating atherosclerotic cardiovascular disease: a systematic review on its biological characteristics, pharmacology, pharmacokinetics, and toxicology

In recent years, the prevalence and fatality rates of atherosclerotic cardiovascular disease have not only shown a consistent rise that cannot be ignored, but have also become a pressing social health problem that requires urgent attention. While interventional surgery and drug therapy offer significant therapeutic results, they often come with common side effects. Geniposide, an active component extracted from the Chinese medicine Gardenia jasminoides Ellis, shows promise in the management of cardiac conditions. This review comprehensively outlines the underlying pharmacological mechanisms by which geniposide exerts its effects on atherosclerosis. Geniposide exhibits a range of beneficial effects including alleviating inflammation, inhibiting the development of macrophage foam cells, improving lipid metabolism, and preventing platelet aggregation and thrombosis. It also demonstrates mitochondrial preservation, anti-apoptotic effects, and modulation of autophagy. Moreover, geniposide shows potential in improving oxidative stress and endoplasmic reticulum stress by maintaining the body's antioxidant and oxidative balance. Additionally, this review comprehensively details the biological properties of geniposide, including methods of extraction and purification, as well as its pharmacokinetics and toxicological characteristics. It further discusses the clinical applications of related biopharmaceuticals, emphasizing the potential of geniposide in the prevention and treatment of atherosclerotic cardiovascular diseases. Furthermore, it highlights the limitations of current research, aiming to provide insights for future studies.

Programmed death of cardiomyocytes in cardiovascular disease and new therapeutic approaches

Cardiovascular diseases (CVDs) have a complex pathogenesis and pose a major threat to human health. Cardiomyocytes have a low regenerative capacity, and their death is a key factor in the morbidity and mortality of many CVDs. Cardiomyocyte death can be regulated by specific signaling pathways known as programmed cell death (PCD), including apoptosis, necroptosis, autophagy, pyroptosis, and ferroptosis, etc. Abnormalities in PCD can lead to the development of a variety of cardiovascular diseases, and there are also molecular-level interconnections between different PCD pathways under the same cardiovascular disease model. Currently, the link between programmed cell death in cardiomyocytes and cardiovascular disease is not fully understood. This review describes the molecular mechanisms of programmed death and the impact of cardiomyocyte death on cardiovascular disease development. Emphasis is placed on a summary of drugs and potential therapeutic approaches that can be used to treat cardiovascular disease by targeting and blocking programmed cell death in cardiomyocytes.

Modified Danzhi XiaoyaoSan inhibits neuroinflammation via regulating TRIM31/NLRP3 inflammasome in the treatment of CUMS depression

The NLRP3 inflammasome is critically involved in the development of depression. The E3 ubiquitin ligase TRIM31 negatively regulates this process by promoting the degradation of NLRP3 through the ubiquitin-proteasome pathway. Modified Danzhi Xiaoyaosan (MDZXYS) has shown good therapeutic effect in both preclinical and clinical depression treatments, yet the underlying mechanisms of its antidepressant effects are not fully understood. In the present study, we aimed to explore the antidepressant mechanisms of MDZXYS, focusing on NLRP3 activation and ubiquitin-mediated degradation. We employed rats with depression induced by chronic unpredictable mild stress (CUMS) and conducted various behavioral tests, including the sucrose preference, forced swimming, and open field tests. Neuronal damage in CUMS-treated rats was assessed using Nissl staining. We measured proinflammatory cytokine levels using ELISA kits and analyzed NLRP3/TRIM31 protein expression via Western blotting and immunofluorescence staining. Our results disclosed that MDZXYS reversed CUMS-induced depression-like behaviors in rats, reduced proinflammatory cytokine levels (IL-1β), and ameliorated neuronal damage in the prefrontal cortex. Additionally, CUMS activated the NLRP3 inflammasome in the prefrontal cortex and upregulated the protein expression of TRIM31. After MDZXYS administration, the expression of NLRP3 inflammasome-associated proteins was reduced, while the expression level of TRIM31 was further increased. Through co-localized immunofluorescence staining, we observed a significant elevation in the co-localization expression of NLRP3 and TRIM31 in the prefrontal cortex of the MDZXYS group. These findings suggest that inhibiting NLRP3 inflammasome-mediated neuroinflammation by modulating the TRIM31signaling pathway may underlie the antidepressant effects of MDZXYS, and further support targeting NLRP3 as a novel approach for the prevention and treatment of depression.

Oleuropein alleviates myocardial ischemia-reperfusion injury by suppressing oxidative stress and excessive autophagy via TLR4/MAPK signaling pathway

BACKGROUND

Myocardial ischemia/reperfusion injury (MIRI) is an important complication of reperfusion therapy, and has a lack of effective prevention and treatment methods. Oleuropein (OP) is a natural strong antioxidant with many protective effects on cardiovascular diseases, but its protective effect on MIRI has not yet been studied in depth.

METHODS

Tert-Butyl hydroperoxide (tBHP) was used to establish an in vitro oxidative stress model. Cell viability was detected by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) and lactate dehydrogenase (LDH). Flow cytometry and fluorescence assays were performed for evaluating the ROS levels and mitochondrial membrane potential (MMP). Immunofluorescence analysis detected the NRF2 nuclear translocation and autophagy indicators. Further, Western blotting and quantitative real-time PCR were performed to evaluate the expression levels of proteins and mRNAs. Molecular docking, CETSA, and molecular interaction analysis explored the binding between OP and TLR4. The protective effects of OP in vivo were determined using a preclinical MIRI rat model.

RESULTS

OP protected against tBHP-treated injury, reduced ROS levels and reversed the damaged MMP. Mechanistically, OP activated NRF2-related antioxidant pathways, inhibited autophagy and attenuated the TLR4/MAPK signaling pathway in tBHP-treated H9C2 cells with a high binding affinity to TLR4 (KD = 37.5 µM). The TLR4 inhibitor TAK242 showed a similar effect as OP. In vivo, OP could alleviate cardiac ischemia/reperfusion injury and it ameliorated adverse cardiac remodeling. Consistent with in vitro studies, OP inhibited TLR4/MAPK and autophagy pathway and activated NRF2-dependent antioxidant pathways in vivo.

CONCLUSION

This study shows that OP binds to TLR4 to regulate oxidative stress and autophagy for protecting damaged cardiomyocytes, supporting that OP can be a potential therapeutic agent for MIRI.

Bardoxolone methyl attenuates doxorubicin-induced cardiotoxicity by inhibiting the TXNIP-NLRP3 pathway through Nrf2 activation

Bardoxolone methyl, which triggers nuclear factor erythroid 2-related factor (Nrf2), has therapeutic effects against myocardial infarction, heart failure, and other diseases. Nrf2 can inhibit the activation of the thioredoxin-interacting protein (TXNIP)/NLR family pyrin domain-containing protein 3 (NLRP3) pathway. Doxorubicin is an anthracycline chemotherapeutic drug associated with cardiotoxicity, limiting its clinical use. In this study, we explored the specific mechanism of the Nrf2-TXNIP-NLRP3 pathway in doxorubicin-induced cardiotoxicity using bardoxolone methyl in animal and cell models. Using in vivo and in vitro experiments, we show that doxorubicin can induce oxidative stress and pyroptosis in the heart. Western blot and co-immunoprecipitation experimental results found that doxorubicin can reduce the interaction between TXNIP and TRX, increase the interaction between TXNIP and NLRP3, and activate the pyroptosis process. Bardoxolone methyl reduces the accumulation of reactive oxygen species in cardiomyocytes through the Nrf2 pathway, inhibits the interaction between TXNIP and NLRP3, and alleviates the progression of myocardial damage and cardiac fibrosis. Bardoxolone methyl lost its therapeutic effect when the expression of Nrf2 was decreased. Additionally, repressing the expression of TXNIP can inhibit the activation of NLRP3 and alleviate myocardial damage caused by doxorubicin. Collectively, our findings confirm that bardoxolone methyl alleviates doxorubicin-induced cardiotoxicity by activating Nrf2 and inhibiting the TXNIP-NLRP3 pathway.

STUB1 is acetylated by KAT5 and alleviates myocardial ischemia-reperfusion injury through LATS2-YAP-β-catenin axis

Myocardial ischemia-reperfusion injury (MIRI) is involved in the pathogenesis of multiple cardiovascular diseases. This study elucidated the biological function of lysine acetyltransferase 5 (KAT5) in cardiomyocyte pyroptosis during MIRI. Oxygen-glucose deprivation/reoxygenation and left anterior descending coronary artery ligation were used to establish MIRI models. Here we show, KAT5 and STIP1 homology and U-box-containing protein 1 (STUB1) were downregulated, while large tumor suppressor kinase 2 (LATS2) was upregulated in MIRI models. KAT5/STUB1 overexpression or LATS2 silencing repressed cardiomyocyte pyroptosis. Mechanistically, KAT5 promoted STUB1 transcription via acetylation modulation, and subsequently caused ubiquitination and degradation of LATS2, which activated YAP/β-catenin pathway. Notably, the inhibitory effect of STUB1 overexpression on cardiomyocyte pyroptosis was abolished by LATS2 overexpression or KAT5 depletion. Our findings suggest that KAT5 overexpression inhibits NLRP3-mediated cardiomyocyte pyroptosis to relieve MIRI through modulation of STUB1/LATS2/YAP/β-catenin axis, providing a potential therapeutic target for MIRI.

AMPK, a key molecule regulating aging-related myocardial ischemia-reperfusion injury

Aging leads to the threat of more diseases to the biological anatomical structure and the decline of disease resistance, increasing the incidence and mortality of myocardial ischemia-reperfusion injury (MI/RI). Moreover, MI/RI promotes damage to an aging heart. Notably, 5'-adenosine monophosphate-activated protein kinase (AMPK) regulates cellular energy metabolism, stress response, and protein metabolism, participates in aging-related signaling pathways, and plays an essential role in ischemia-reperfusion (I/R) injury diseases. This study aims to introduce the aging theory, summarize the interaction between aging and MI/RI, and describe the crosstalk of AMPK in aging and MI/RI. We show how AMPK can offer protective effects against age-related stressors, lifestyle factors such as alcohol consumption and smoking, and hypertension. We also review some of the clinical prospects for the development of interventions that harness the effect of AMPK to treat MI/RI and other age-related cardiovascular diseases.

Network pharmacology and in vivo evidence of the pharmacological mechanism of geniposide in the treatment of atherosclerosis

BACKGROUND

Atherosclerosis (AS) is a fundamental pathological state in various cardiovascular diseases. Geniposide, which is the main active component of Gardenia jasminides, is effective against AS. However, the underlying molecular mechanisms remain unclear. Here, we sought to elucidate them.

METHODS

The targets of AS and geniposide were collected from online public databases. The potential mechanism of Geniposide in treating AS was predicted by constructing a protein-protein interaction (PPI) network and conducting Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway enrichment analyses. Hub proteins and core pathways were verified by molecular docking and in vivo experiments. Moreover, the effect of geniposide on AS was assessed by measuring the atherosclerotic plaque area in the thoracic aorta of mice. ApoE-/- mice were used to establish AS models and randomly divided into different groups. Two different doses of geniposide were administered to the mice. Hematoxylin and eosin (HE) staining was performed to evaluate the effects of geniposide on AS. Oil Red O and Sirius Red staining were used to evaluate plaque stability. The protein expression of key markers involved in the signalling pathways was examined using western blotting and immunofluorescence.

RESULTS

A total of 239 active targets, 3418 AS-related disease targets, and 129 overlapping targets were identified. Hub genes were detected, and molecular docking revealed that geniposide strongly interacted with hub proteins (AKT1, VEGFA, CTNNB1, MMP9, and EGFR). Moreover, 109 signalling pathways, including the Rap1 signalling pathway, were identified using enrichment analysis. The results of in vivo experiments demonstrated that geniposide reduced body weight and blood lipid levels, alleviated the formation of atherosclerotic plaques, enhanced plaque stability, and inhibited inflammation, at least partially, by activating the Rap1/PI3K/Akt signalling pathway in ApoE-/- mice.

CONCLUSION

Geniposide can alleviate AS and enhance the stability of atherosclerotic plaques by regulating the Rap1/PI3K/Akt signalling pathway.

Phillygenin Alleviates Arthritis through the Inhibition of the NLRP3 Inflammasome and Ferroptosis by AMPK

We investigated the potential arthritis-inducing effects of Phillygenin and its underlying mechanisms. RAW264.7 cells were stimulated with lipopolysaccharide to induce inflammation. Phillygenin was found to reduce arthritis score, histopathological changes, paw edema, spleen index, and ALP levels in a dose-dependent manner in a model of arthritis. Additionally, Phillygenin was able to decrease levels of inflammation markers in serum samples of mice with arthritis and also inhibited inflammation markers in the cell supernatant of an in vitro model of arthritis. Phillygenin increased cell viability and JC-1 disaggregation, enhanced calcien-AM/CoCl2, reduced LDH activity levels and IL-1a levels, and inhibited Calcein/PI levels and iron concentration in an in vitro model. Phillygenin was also found to reduce ROS-induced oxidative stress and Ferroptosis, and suppress the NLRP3 inflammasome in both in vivo and in vitro models through AMPK. In the in vivo model, Phillygenin was observed to interact with AMPK protein. These findings suggest that Phillygenin may be a potential therapeutic target for preventing arthritis by inhibiting NLRP3 inflammasome and Ferroptosis through AMPK. This indicates that Phillygenin could have disease-modifying effects on arthritis.

Geniposide alleviated hydrogen peroxide-induced apoptosis of human hepatocytes via altering DNA methylation

Geniposide (GP) is the homology of medicine and food with bioactive effects of antioxidation and resistance to apoptosis in the liver. It's of great significance to explore the biosafety exposure limits and action mechanisms of GP. This study detected the global DNA methylation microenvironment and the regulation of specific genes in GP against cellular apoptosis induced by hydrogen peroxide (H2O2) of human hepatocyte L-02 cells. The half inhibitory concentration (IC50) of GP on normal L-02 cells was 57.7 mg/mL. GP exerted new epigenetic activity, increased DNMT1, decreased TET1 and TET2 expression, and reversed the demethylation effect to some extent, thereby increasing the overall genomic DNA methylation level at the concentration of 900 μg/mL. GP pretreatment could also adjust the level of P53, Bcl-2 and AKT altered by H2O2, reducing their specific DNA methylation levels in the promoter regions of AKT and Bcl-2 to inhibit apoptosis. Taken together, GP regulates the global DNA methylation level and controls the expression changes of P53, Bcl-2 and AKT, jointly inhibiting the occurrence of apoptosis in human hepatocytes and providing the newly theoretical references for its safety evaluation.

Geniposide ameliorates acute kidney injury via enhancing the phagocytic ability of macrophages towards neutrophil extracellular traps

Acute kidney injury (AKI) is a clinically serious disorder associated with high mortality rates and an increased risk of progression to end-stage renal disease. As an essential supportive treatment for patients with respiratory failure, mechanical ventilation not only save many critically ill patients, but also affect glomerular filtration function by changing renal hemodynamics, neurohumoral and positive end-expiratory pressure, eventually leading to AKI. AMP-activated protein kinase (AMPK), a crucial energy homeostasis regulator, could enhance macrophage phagocytic ability and inhibit inflammation, but whether it can engulf neutrophil extracellular traps (NETs) and alleviate mechanical ventilation-associated AKI is still unclear. In this study, we found that geniposide significantly ameliorated histopathological damage, reduced serum Cre and BUN levels. Besides, geniposide can also induce AMPK activation and enhance macrophage phagocytic ability toward NETs. Moreover, geniposide can markedly reduce the levels of high mobility group box 1 (HMGB1), and these effects were dependent on AMPK-PI3K/Akt signaling. Altogether, these results indicated that geniposide promoted macrophage efferocytosis by inducing AMPK-PI3K/Akt signaling activation, clearing NETs and ameliorating AKI.

Dexmedetomidine abates myocardial ischemia reperfusion injury through inhibition of pyroptosis via regulation of miR-665/MEF2D/Nrf2 axis

The current study intended to delve into the mechanisms of dexmedetomidine (Dex) in regulating myocardial pyroptosis against myocardial ischemia/reperfusion injury (MIRI). The rat MIRI models were induced by ligation/release of the coronary artery in vivo and Langendorff perfusion ex vivo. Hemodynamic parameters, infarction sizes, and histopathological changes were assessed to understand the effects of Dex on MIRI. We explored the mechanisms through functional experiments on an H9c2 cell hypoxia/reoxygenation (H/R) model. Cell viability and apoptosis were evaluated using cell counting kit 8 (CCK-8) and AV/PI dual staining respectively. The expressions of miR-665 and MEF2D mRNA were detected by qRT-PCR. Western blot was employed to determine the expression levels of pyroptosis- and signaling pathway- related proteins. The interplays between miR-665 and MEF2D were validated by Dual-luciferase reporter assays. Our findings indicated that Dex preconditioning dramatically attenuated hemodynamic derangements, infarct size, and histopathological damage in rats undergoing MIRI. Dex markedly augmented cell viability, while suppressing cell apoptosis and expressions of NLRP3, cleaved-caspase-1, ASC, GSDMD, IL-1β, and IL-18 in H9c2 cells subjected to H/R injury. MiR-665 was significantly upregulated, MEF2D and Nrf2 downregulated following H/R, whereas Dex preconditioning reversed these changes. MEF2D was validated to be a target gene of miR-665. Overexpression of miR-665 decreased the expression of MEF2D and blunted the protective effects of Dex in H9c2 cells. Moreover, the functional rescue experiment further verified that Dex regulated MEF2D/Nrf2 pathway via miR-665. In conclusion, Dex mitigates MIRI through inhibiting pyroptosis via regulating miR-665/MEF2D/Nrf2 axis.

Protective effect and possible mechanisms of geniposide for ischemia-reperfusion injury: A systematic review with meta-analysis and network pharmacology of preclinical evidence

Background

Geniposide, as a pharmacologically bioactive component, is derived from a classic and common Chinese herb, Gardenia jasminoides Ellis. Geniposide has been shown to be effective for treating I/R injury in recent studies. Current effectively pharmaceutical treatments are scarce, and treatment based on geniposide may become a novel option. As far as we know, this research is the initial systematic evaluation of the protective effects of geniposide in I/R injury.

Aim of the study

This study is engrossed in evaluating the mechanism of action of geniposide in I/R injury through a preclinical systematic review with meta-analysis and network pharmacology.

Materials and methods

We built a systematic review which provided a view of effect and mechanism of geniposide for I/R injury. Based on seven databases, an open-ended search from their inception to August 31st, 2022, was conducted. Animal studies on the effects of geniposide in I/R injury were considered. The data was analyzed using Review Manager 5.3, and bias was assessed using the CAMARADES 10-item scale. 13 articles including 279 animals were selected finally. And network pharmacology was joined to elucidate the mechanism.

Results

According to the meta-analysis, in I/R injury, geniposide can attenuate cardiomyocytes viability and the size of MI, decrease the volume of cerebral infraction and neurological score, decrease serum ALT and AST activity, and downregulated serum Cr and BUN. The review found that geniposide protects against I/R injury by inhibiting apoptosis, oxidation, inflammation and improvement of autophagy and mitochondrial respiration, which is consistent with the results of the network pharmacology screening.

Conclusion

This preclinical systematic review including meta-analysis and network pharmacology, which was the first one summarizing the relationship between geniposide and ischemia diseases, shows a novel therapy for I/R injury and appears an enticing implication of geniposide in I/R injury, and further research is looked forward. Given the restricted quantity of included researches and the unclear risk of bias of the studies, we should interpret the results with caution.

Geniposide alleviated bile acid-associated NLRP3 inflammasome activation by regulating SIRT1/FXR signaling in bile duct ligation-induced liver fibrosis

BACKGROUND

Geniposide (GE), the active compound derived from Gardeniae Fructus, possesses valuable bioactivity for liver diseases, but GE effects on bile duct ligation (BDL)-induced cholestasis remain unclear. This study aimed to elucidate the influence of GE on BDL-induced liver fibrosis and to investigate the underlying mechanisms.

METHODS

GE (25 or 50 mg/kg) were intragastrical administered to C57BL/6 J mice for two weeks to characterize the hepatoprotective effect of GE on BDL-induced liver fibrosis. NLRP3 inflammasome activation was detected in vivo, and BMDMs were isolated to explore whether GE directly inhibited NLRP3 inflammasome activation. Serum bile acid (BA) profiles were assessed utilizing UPLC-MS/MS, and the involvement of SIRT1/FXR pathways was identified to elucidate the role of SIRT1/FXR in the hepaprotective effect of GE. The veritable impact of SIRT1/FXR signaling was further confirmed by administering the SIRT1 inhibitor EX527 (10 mg/kg) to BDL mice treated with GE.

RESULTS

GE treatment protected mice from BDL-induced liver fibrosis, with NLRP3 inflammasome inhibition. However, development in vitro experiments revealed that GE could not directly inhibit NLRP3 activation under ATP, monosodium urate, and nigericin stimulation. Further mechanistic data showed that GE activated SIRT1, which subsequently deacetylated FXR and restored CDCA, TUDCA, and TCDCA levels, thereby contributing to the observed hepaprotective effect of GE. Notably, EX527 treatment diminished the hepaprotective effect of GE on BDL-induced liver fibrosis.

CONCLUSION

This study first proved the hepaprotective effect of GE on liver fibrosis in BDL mice, which was closely associated with the restoration of BA homeostasis and NLRP3 inflammasome inhibition. The activation of SIRT1 and the subsequent FXR deacetylation restored the BA profiles, especially CDCA, TUDCA, and TCDCA contents, which was the main contributor to NLRP3 inhibition and the hepaprotective effect of GE. Overall, our work provides novel insights that GE as well as Gardeniae Fructus might be the potential attractive candidate for ameliorating BDL-induced liver fibrosis.

Therapeutic interventions target the NLRP3 inflammasome in ulcerative colitis: Comprehensive study

One of the significant health issues in the world is the prevalence of ulcerative colitis (UC). UC is a chronic disorder that mainly affects the colon, beginning with the rectum, and can progress from asymptomatic mild inflammation to extensive inflammation of the entire colon. Understanding the underlying molecular mechanisms of UC pathogenesis emphasizes the need for innovative therapeutic approaches based on identifying molecular targets. Interestingly, in response to cellular injury, the NLR family pyrin domain containing 3 (NLRP3) inflammasome is a crucial part of the inflammation and immunological reaction by promoting caspase-1 activation and the release of interleukin-1β. This review discusses the mechanisms of NLRP3 inflammasome activation by various signals and its regulation and impact on UC.

Pyroptosis: A Newly Discovered Therapeutic Target for Ischemia-Reperfusion Injury

Ischemia-reperfusion (I/R) injury, uncommon among patients suffering from myocardial infarction, stroke, or acute kidney injury, can result in cell death and organ dysfunction. Previous studies have shown that different types of cell death, including apoptosis, necrosis, and autophagy, can occur during I/R injury. Pyroptosis, which is characterized by cell membrane pore formation, pro-inflammatory cytokine release, and cell burst, and which differentiates itself from apoptosis and necroptosis, has been found to be closely related to I/R injury. Therefore, targeting the signaling pathways and key regulators of pyroptosis may be favorable for the treatment of I/R injury, which is far from adequate at present. This review summarizes the current status of pyroptosis and its connection to I/R in different organs, as well as potential treatment strategies targeting it to combat I/R injury.