Sacubitril/Valsartan Improves Cardiac Function and Decreases Myocardial Fibrosis Via Downregulation of Exosomal miR-181a in a Rodent Chronic Myocardial Infarction Model

The potential roles of exosomes in pathological cardiomyocyte hypertrophy mechanisms and therapy: A review

Pathological cardiac hypertrophy, characterized by the enlargement of cardiac muscle cells, leads to serious cardiac conditions and stands as a major global health issue. Exosomes, comprising small lipid bilayer vesicles, are produced by various cell types and found in numerous bodily fluids. They play a pivotal role in intercellular communication by transferring bioactive cargos to recipient cells or activating signaling pathways in target cells. Exosomes from cardiomyocytes, endothelial cells, fibroblasts, and stem cells are key in regulating processes like cardiac hypertrophy, cardiomyocyte survival, apoptosis, fibrosis, and angiogenesis within the context of cardiovascular diseases. This review delves into exosomes' roles in pathological cardiac hypertrophy, first elucidating their impact on cell communication and signaling pathways. It then advances to discuss how exosomes affect key hypertrophic processes, including metabolism, fibrosis, oxidative stress, and angiogenesis. The review culminates by evaluating the potential of exosomes as biomarkers and their significance in targeted therapeutic strategies, thus emphasizing their critical role in the pathophysiology and management of cardiac hypertrophy.

The good, the bad and the ugly: the impact of extracellular vesicles on the cardiovascular system

Cardiovascular diseases (CVDs), which encompass a myriad of pathological conditions that affect the heart and/or the blood vessels, remain the major cause of morbidity and mortality worldwide. By transferring a wide variety of bioactive molecules, including proteins and microRNAs (miRNAs), extracellular vesicles (EVs) are recognized as key players in long-range communication across the cardiovascular system. It has been demonstrated that these highly heterogeneous nanosized vesicles participate both in the maintenance of homeostasis of the heart and vessels, and contribute to the pathophysiology of CVDs, thus emerging as promising tools for diagnosis, prognosis and treatment of multiple CVDs. In this review, we highlight the beneficial roles of EV-mediated communication in regulating vascular homeostasis, and inter-organ crosstalk as a potential mechanism controlling systemic metabolic fitness. In addition, the impact of EV secretion in disease development is described, particularly focusing on cardiac remodelling following ischaemia, atherogenesis and atrial fibrillation progression. Finally, we discuss the potential of endogenous and bioengineered EVs as therapeutic tools for CVDs, as well as the suitability of assessing the molecular signature of circulating EVs as a non-invasive predictive marker of CVD onset and progression. This rapidly expanding field of research has established the role of EVs as key conveyors of both cardioprotective and detrimental signals, which might be of relevance in uncovering novel therapeutic targets and biomarkers of CVDs.

A Machine Learning Model Based on microRNAs for the Diagnosis of Essential Hypertension

INTRODUCTION

Hypertension is a major and modifiable risk factor for cardiovascular diseases. Essential, primary, or idiopathic hypertension accounts for 90-95% of all cases. Identifying novel biomarkers specific to essential hypertension may help in understanding pathophysiological pathways and developing personalized treatments. We tested whether the integration of circulating microRNAs (miRNAs) and clinical risk factors via machine learning modeling may provide useful information and novel tools for essential hypertension diagnosis and management.

MATERIALS AND METHODS

In total, 174 participants were enrolled in the present observational case-control study, among which, there were 89 patients with essential hypertension and 85 controls. A discovery phase was conducted using small RNA sequencing in whole blood samples obtained from age- and sex-matched hypertension patients (n = 30) and controls (n = 30). A validation phase using RT-qPCR involved the remaining 114 participants. For machine learning, 170 participants with complete data were used to generate and evaluate the classification model.

RESULTS

Small RNA sequencing identified seven miRNAs downregulated in hypertensive patients as compared with controls in the discovery group, of which six were confirmed with RT-qPCR. In the validation group, miR-210-3p/361-3p/362-5p/378a-5p/501-5p were also downregulated in hypertensive patients. A machine learning support vector machine (SVM) model including clinical risk factors (sex, BMI, alcohol use, current smoker, and hypertension family history), miR-361-3p, and miR-501-5p was able to classify hypertension patients in a test dataset with an AUC of 0.90, a balanced accuracy of 0.87, a sensitivity of 0.83, and a specificity of 0.91. While five miRNAs exhibited substantial downregulation in hypertension patients, only miR-361-3p and miR-501-5p, alongside clinical risk factors, were consistently chosen in at least eight out of ten sub-training sets within the SVM model.

CONCLUSIONS

This study highlights the potential significance of miRNA-based biomarkers in deepening our understanding of hypertension's pathophysiology and in personalizing treatment strategies. The strong performance of the SVM model highlights its potential as a valuable asset for diagnosing and managing essential hypertension. The model remains to be extensively validated in independent patient cohorts before evaluating its added value in a clinical setting.

Sacubitril/valsartan mitigates cardiac remodeling, systolic dysfunction, and preserves mitochondrial quality in a rat model of mitral regurgitation

Sacubitril/valsartan (SAC/VAL), an angiotensin receptor blocker-neprilysin inhibitor, has been widely used to treat several types of heart failure. Nevertheless, the effects of drugs in mitral regurgitation patients, from the molecular level to therapeutic effects, remain unclear. This study investigates the roles of SAC/VAL on cardiac function, mitochondrial quality, autophagy, mitophagy, and natriuretic peptides in a rat model of chronic mitral regurgitation. Male Sprague-Dawley rats underwent MR induction (n = 16) and sham surgeries (n = 8). Four weeks post-surgery confirmed MR rats were randomly divided into MR (n = 8) and SAC/VAL (n = 8) groups. The SAC/VAL group was administered SAC/VAL, whereas the MR and the sham rats received vehicle via oral gavage daily for 8 weeks. Cardiac geometry, function, and myocardial fibrosis were assessed by echocardiography and histopathology. Spectrophotometry and real-time PCR were performed to assess the pharmacological effects on mitochondrial quality, autophagy, mitophagy, and natriuretic peptides. MR rats demonstrated significant left heart dilation and left ventricular systolic dysfunction compared with the sham group, which could be significantly improved by SAC/VAL. In addition, SAC/VAL significantly reduced myocardial cardiac remodeling and fibrosis in MR rats. SAC/VAL improved the mitochondrial quality by attenuating mitochondrial reactive oxygen species production and mitochondrial depolarization compared with the MR group. Also, the upregulation of autophagy-related, mitophagy-related, and natriuretic peptide system gene expression in MR rats was attenuated by SAC/VAL treatment. In conclusion, this study demonstrated that SAC/VAL treatment could provide numerous beneficial effects in MR conditions, suggesting that this drug may be an effective treatment for MR.

Vericiguat preserved cardiac function and mitochondrial quality in a rat model of mitral regurgitation

AIMS

New drugs for heart failure (HF) that target restoring the impaired NO-sGC-cGMP pathway are being developed. We aimed to investigate the effects of vericiguat, an sGC stimulator, on cardiac function, blood pressure (BP), cardiac mitochondrial quality, and cardiac fibrosis in rat models of chronic mitral regurgitation (MR).

MATERIALS AND METHODS

We surgically induced MR in 20 Sprague-Dawley rats and performed sham procedures on 10 rats (negative control). Four weeks post-surgery, we randomly divided the MR rats into two groups: MR group and MR + vericiguat group. Vericiguat (0.5 mg/kg, PO) was administered once a day via oral gavage for 8 weeks, while the sham and MR groups received equivalent volumes of drinking water instead. We took echocardiography and BP measurements at baseline (4 weeks post-surgery) and at the end of study (8 weeks after treatment). At the study end, all rats were euthanized and their hearts were immediately collected, weighed, and used for histopathology and mitochondrial quality assessments.

KEY FINDINGS

Vericiguat preserved cardiac functions and structural remodeling in the MR rats, with significantly lower systolic BPs than baseline values (P < 0.05). Additionally, vericiguat significantly improved the mitochondrial quality by attenuating ROS production, depolarization and swelling when comparing the values in both groups (P < 0.05). The fibrosis area also significantly decreased in the MR + vericiguat group (P < 0.05).

SIGNIFICANCE

Vericiguat demonstrated cardioprotective effects on cardiac function, BP, and fibrosis by preserving mitochondrial quality in rats with HF due to MR.

Circulating MicroRNAs Identify Early Phenotypic Changes in Sarcomeric Hypertrophic Cardiomyopathy

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is the most common genetic cardiomyopathy. Pathogenic germline variation in genes encoding the sarcomere is the predominant cause of disease. However diagnostic features, including unexplained left ventricular hypertrophy, typically do not develop until late adolescence or after. The early stages of disease pathogenesis and the mechanisms underlying the transition to a clinically overt phenotype are not well understood. In this study, we investigated if circulating microRNAs (miRNAs) could stratify disease stage in sarcomeric HCM.

METHODS

We performed arrays for 381 miRNAs using serum from HCM sarcomere variant carriers with and without a diagnosis of HCM and healthy controls. To identify differentially expressed circulating miRNAs between groups, multiple approaches were used including random forest, Wilcoxon rank sum test, and logistic regression. The abundance of all miRNAs was normalized to miRNA-320.

RESULTS

Of 57 sarcomere variant carriers, 25 had clinical HCM and 32 had subclinical HCM with normal left ventricular wall thickness (21 with early phenotypic manifestations and 11 with no discernible phenotypic manifestations). Circulating miRNA profile differentiated healthy controls from sarcomere variant carriers with subclinical and clinical disease. Additionally, circulating miRNAs differentiated clinical HCM from subclinical HCM without early phenotypic changes; and subclinical HCM with and without early phenotypic changes. Circulating miRNA profiles did not differentiate clinical HCM from subclinical HCM with early phenotypic changes, suggesting biologic similarity between these groups.

CONCLUSIONS

Circulating miRNAs may augment the clinical stratification of HCM and improve understanding of the transition from health to disease in sarcomere gene variant carriers.

The emerging role of sacubitril/valsartan in pulmonary hypertension with heart failure

Pulmonary hypertension due to left heart disease (PH-LHD) represents approximately 65%-80% of all patients with PH. The progression, prognosis, and mortality of individuals with left heart failure (LHF) are significantly influenced by PH and right ventricular (RV) dysfunction. Consequently, cardiologists should devote ample attention to the interplay between HF and PH. Patients with PH and HF may not receive optimal benefits from the therapeutic effects of prostaglandins, endothelin receptor antagonists, or phosphodiesterase inhibitors, which are specific drugs for pulmonary arterial hypertension (PAH). Sacubitril/valsartan, the angiotensin receptor II blocker-neprilysin inhibitor (ARNI), was recommended as the first-line therapy for patients with heart failure with reduced ejection fraction (HFrEF) by the 2021 European Society of Cardiology Guidelines. Although ARNI is effective in treating left ventricular (LV) enlargement and lower ejection fraction, its efficacy in treating individuals with PH and HF remains underexplored. Considering its vasodilatory effect at the pre-capillary level and a natriuretic drainage role at the post-capillary level, ARNI is believed to have a broad range of potential applications in treating PH-LHD. This review discusses the fundamental pathophysiological connections between PH and HF, emphasizing the latest research and potential benefits of ARNI in PH with various types of LHF and RV dysfunction.

Comprehensive analysis of the RNA transcriptome expression profiles and construction of the ceRNA network in heart failure patients with sacubitril/valsartan therapeutic heterogeneity after acute myocardial infarction

Sacubitril/valsartan has a noteworthy advantage in improving ventricular remodelling, as well as reducing cardiovascular mortality and the rate of heart failure (HF) readmission. However, clinically, some patients with HF still have low sensitivity to sacubitril/valsartan, indicating sacubitril/valsartan resistance (SVR). A total of 46 patients with HF after AMI (23 SVR and 23 non-sacubitril/valsartan resistance (NSVR)) were selected. Five SVR and 5 matched NSVR samples were screened for differentially expressed ncRNAs along with mRNAs. A total of 124 differentially expressed miRNAs, 137 circRNAs, 237 lncRNAs and 50 mRNAs were screened by RNA sequencing technology. After quantitative real-time PCR (qRT‒PCR) verification of selected biomarkers in 18 pairs of samples, we found that for patients with SVR, hsa-miR-543, hsa-miR-642b-5p, hsa-miR-760, hsa_circ_0137499, ENST00000474394, ENST00000528337, E2F1, NEAT1, and YTHDF2 were upregulated, and hsa-miR-424-5p, hsa-miR-21-3p, hsa_circRNA_0003275, hsa_circRNA_0004494, hsa_circ_0093522, ENST00000467951, ENST00000558177, ACTA2, ANPEP, and CAMP were downregulated. Then, with the help of our constructed ceRNA network and functional annotation enrichment, we speculated that inflammatory pathways (such as the apelin signalling pathway) and lipid metabolism pathways (such as fatty acid metabolism) may be involved in the regulation of SVR. These discoveries lay a foundation for further mechanistic research and provide a direction for individualized drug administration.

Post-myocardial infarction fibrosis: Pathophysiology, examination, and intervention

Cardiac fibrosis plays an indispensable role in cardiac tissue homeostasis and repair after myocardial infarction (MI). The cardiac fibroblast-to-myofibroblast differentiation and extracellular matrix collagen deposition are the hallmarks of cardiac fibrosis, which are modulated by multiple signaling pathways and various types of cells in time-dependent manners. Our understanding of the development of cardiac fibrosis after MI has evolved in basic and clinical researches, and the regulation of fibrotic remodeling may facilitate novel diagnostic and therapeutic strategies, and finally improve outcomes. Here, we aim to elaborate pathophysiology, examination and intervention of cardiac fibrosis after MI.

The history and mystery of sacubitril/valsartan: From clinical trial to the real world

Heart failure is a serious threat to human health, with morbidity and mortality rates increasing despite the existence of multiple treatment options. Therefore, it is necessary to identify new therapeutic targets for this disease. Sacubitril/valsartan is a supramolecular sodium salt complex of the enkephalinase inhibitor prodrug sacubitril and the angiotensin receptor blocker valsartan. Its combined action increases endogenous natriuretic peptides while inhibiting the renin-angiotensin-aldosterone system and exerting cardioprotective effects. Clinical evidence suggests that sacubitril/valsartan is superior to conventional renin-angiotensin-aldosterone inhibitor therapy for patients with reduced ejection fraction heart failure who can tolerate angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers. The therapy reduces the risk of heart failure hospitalization, cardiovascular mortality, and all-cause mortality and has a better safety and tolerability record. This review describes the potential pathophysiological mechanisms of cardiomyocyte injury amelioration by sacubitril/valsartan. We explore the protective effects of sacubitril/valsartan and outline the therapeutic value in patients with heart failure by summarizing the results of recent large clinical trials. Furthermore, a preliminary outlook shows that sacubitril/valsartan may be effective at treating other diseases, and provides some exploratory observations that lay the foundation for future studies on this drug.

Impact of Sacubitril/Valsartan on Circulating microRNA in Patients with Heart Failure

Sacubitril/Valsartan, used for the treatment of heart failure (HF), is a combination of two drugs, an angiotensin receptor inhibitor, and a neprilysin inhibitor, which activates vasoactive peptides. Even though its beneficial effects on cardiac functions have been demonstrated, the mechanisms underpinning these effects remain poorly understood. To achieve more mechanistic insights, we analyzed the profiles of circulating miRNAs in plasma from patients with stable HF with reduced ejection function (HFrEF) and treated with Sacubitril/Valsartan for six months. miRNAs are short (22-24 nt) non-coding RNAs, which are not only emerging as sensitive and stable biomarkers for various diseases but also participate in the regulation of several biological processes. We found that in patients with high levels of miRNAs, specifically miR-29b-3p, miR-221-3p, and miR-503-5p, Sacubitril/Valsartan significantly reduced their levels at follow-up. We also found a significant negative correlation of miR-29b-3p, miR-221-3p, and miR-503-5p with VO2 at peak exercise, whose levels decrease with HF severity. Furthermore, from a functional point of view, miR-29b-3p, miR-221-3p, and miR-503-5p all target Phosphoinositide-3-Kinase Regulatory Subunit 1, which encodes regulatory subunit 1 of phosphoinositide-3-kinase. Our findings support that an additional mechanism through which Sacubitril/Valsartan exerts its functions is the modulation of miRNAs with potentially relevant roles in HFrEF pathophysiology.

The Role of ncRNAs in Cardiac Infarction and Regeneration

Myocardial infarction is the most prevalent cardiovascular disease worldwide, and it is defined as cardiomyocyte cell death due to a lack of oxygen supply. Such a temporary absence of oxygen supply, or ischemia, leads to extensive cardiomyocyte cell death in the affected myocardium. Notably, reactive oxygen species are generated during the reperfusion process, driving a novel wave of cell death. Consequently, the inflammatory process starts, followed by fibrotic scar formation. Limiting inflammation and resolving the fibrotic scar are essential biological processes with respect to providing a favorable environment for cardiac regeneration that is only achieved in a limited number of species. Distinct inductive signals and transcriptional regulatory factors are key components that modulate cardiac injury and regeneration. Over the last decade, the impact of non-coding RNAs has begun to be addressed in many cellular and pathological processes including myocardial infarction and regeneration. Herein, we provide a state-of-the-art review of the current functional role of diverse non-coding RNAs, particularly microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), in different biological processes involved in cardiac injury as well as in distinct experimental models of cardiac regeneration.

Neprilysin Inhibition in the Prevention of Anthracycline-Induced Cardiotoxicity

Anthracycline-induced cardiotoxicity (AIC) poses a clinical challenge in the management of cancer patients. AIC is characterized by myocardial systolic dysfunction and remodeling, caused by cardiomyocyte DNA damage, oxidative stress, mitochondrial dysfunction, or renin-angiotensin-aldosterone system (RAAS) dysregulation. In the past decade, after positive results of a PARADIGM-HF trial, a new class of drugs, namely angiotensin receptor/neprilysin inhibitors (ARNi), was incorporated into the management of patients with heart failure with reduced ejection fraction. As demonstrated in a variety of preclinical studies of cardiovascular diseases, the cardioprotective effects of ARNi administration are associated with decreased oxidative stress levels, the inhibition of myocardial inflammatory response, protection against mitochondrial damage and endothelial dysfunction, and improvement in the RAAS imbalance. However, data on ARNi's effectiveness in the prevention of AIC remains limited. Several reports of ARNi administration in animal models of AIC have shown promising results, as ARNi prevented ventricular systolic dysfunction and electrocardiographic changes and ameliorated oxidative stress, mitochondrial dysfunction, endoplasmic reticulum stress, and the inflammatory response associated with anthracyclines. There is currently an ongoing PRADAII trial aimed to assess the efficacy of ARNi in patients receiving breast cancer treatment, which is expected to be completed by late 2025.

Extracellular Vesicles and Pathological Cardiac Hypertrophy

Pathological cardiac hypertrophy is a well-recognized risk factor for cardiovascular diseases (CVDs). Although lots of efforts have been made to illustrate the underlying molecular mechanisms, many issues remain undiscovered. Recently, intercellular communication by delivering small molecules between different cell types in the progression of cardiac hypertrophy has been reported, including bioactive nucleic acids or proteins. These extracellular vesicles (EVs) may act in an autocrine or paracrine manner between cardiomyocytes and noncardiomyocytes to provoke or inhibit cardiac remodeling and hypertrophy. Besides, EVs can be used as novel diagnostic or prognostic biomarkers in cardiac hypertrophy and also may serve as potential therapeutic targets due to its biocompatible nature and low immunogenicity. In this chapter, we will first summarize the current knowledge about EVs from different cells in pathological cardiac hypertrophy. Then, we will focus on the value of EVs as therapeutic agents and biomarkers for pathological myocardial hypertrophy.

The Role of microRNA in the Development, Diagnosis, and Treatment of Cardiovascular Disease: Recent Developments

Since their discovery in 1993, microRNAs (miRNAs) have emerged as important regulators of many crucial cellular processes, and their dysregulation have been shown to contribute to multiple pathologic conditions, including cardiovascular disease (CVD). miRNAs have been found to regulate the expression of various genes involved in cardiac development and function and in the development and progression of CVD. Many miRNAs are master regulators fine-tuning the expression of multiple, often interrelated, genes involved in inflammation, apoptosis, fibrosis, senescence, and other processes crucial for the development of different forms of CVD. This article presents a review of recent developments in our understanding of the role of miRNAs in the development of CVD and surveys their potential applicability as therapeutic targets and biomarkers to facilitate CVD diagnosis, prognosis, and treatment. There are currently multiple potential miRNA-based therapeutic agents in different stages of development, which can be grouped into two classes: miRNA mimics (replicating the sequence and activity of their corresponding miRNAs) and antagomiRs (antisense inhibitors of specific miRNAs). However, in spite of promising preliminary data and our ever-increasing knowledge about the mechanisms of action of specific miRNAs, miRNA-based therapeutics and biomarkers have yet to be approved for clinical applications. SIGNIFICANCE STATEMENT: Over the last few years microRNAs have emerged as crucial, specific regulators of the cardiovascular system and in the development of cardiovascular disease, by posttranscriptional regulation of their target genes. The minireview presents the most recent developments in this area of research, including the progress in diagnostic and therapeutic applications of microRNAs. microRNAs seem very promising candidates for biomarkers and therapeutic agents, although some challenges, such as efficient delivery and unwanted effects, need to be resolved.

Extracellular vesicles mediate biological information delivery: A double-edged sword in cardiac remodeling after myocardial infarction

Acute myocardial infarction (AMI) is a severe ischemic disease with high morbidity and mortality worldwide. Maladaptive cardiac remodeling is a series of abnormalities in cardiac structure and function that occurs following myocardial infarction (MI). The pathophysiology of this process can be separated into two distinct phases: the initial inflammatory response, and the subsequent longer-term scar revision that includes the regression of inflammation, neovascularization, and fibrotic scar formation. Extracellular vesicles are nano-sized lipid bilayer vesicles released into the extracellular environment by eukaryotic cells, containing bioinformatic transmitters which are essential mediators of intercellular communication. EVs of different cellular origins play an essential role in cardiac remodeling after myocardial infarction. In this review, we first introduce the pathophysiology of post-infarction cardiac remodeling, as well as the biogenesis, classification, delivery, and functions of EVs. Then, we explore the dual role of these small molecule transmitters delivered by EVs in post-infarction cardiac remodeling, including the double-edged sword of pro-and anti-inflammation, and pro-and anti-fibrosis, which is significant for post-infarction cardiac repair. Finally, we discuss the pharmacological and engineered targeting of EVs for promoting heart repair after MI, thus revealing the potential value of targeted modulation of EVs and its use as a drug delivery vehicle in the therapeutic process of post-infarction cardiac remodeling.

Combined Therapy of Low-Dose Angiotensin Receptor-Neprilysin Inhibitor and Sodium-Glucose Cotransporter-2 Inhibitor Prevents Doxorubicin-Induced Cardiac Dysfunction in Rodent Model with Minimal Adverse Effects

Although cancer-therapy-related cardiac dysfunction (CTRCD) is a critical issue in clinical practice, there is a glaring lack of evidence regarding cardiotoxicity management. To determine an effective and suitable dosage of treatment using angiotensin receptor-neprilysin inhibitors (ARNI) with sodium-glucose cotransporter 2 inhibitors (SGLT2i), we adopted a clinically relevant rodent model with doxorubicin, which would mimic cardiac dysfunction in CTRCD patients. After the oral administration of drugs (vehicle, SGLT2i, ARNI, Low-ARNI/SGLT2i, ARNI/SGLT2i), several physiologic parameters, including hemodynamic change, cardiac function, and histopathology, were evaluated. Bulk RNA-sequencing was performed to obtain insights into the molecular basis of a mouse heart response to Low-ARNI/SGLT2i treatment. For the first time, we report that the addition of low-dose ARNI with SGLT2i resulted in greater benefits than ARNI, SGLT2i alone or ARNI/SGLT2i combination in survival rate, cardiac function, hemodynamic change, and kidney function against doxorubicin-induced cardiotoxicity through peroxisome proliferator-activated receptor signaling pathway. Low-dose ARNI with SGLT2i combination treatment would be practically beneficial for improving cardiac functions against doxorubicin-induced heart failure with minimal adverse effects. Our findings suggest the Low-ARNI/SGLT2i combination as a feasible novel strategy in managing CTRCD patients.

Effects of sacubitril-valsartan on heart failure patients with mid-range ejection fractions: A systematic review and meta-analysis

Aim: The effect of sacubitril-valsartan (ARNI) in heart failure (HF) patients with mid-range ejection fractions (HFmrEF) remains unclear. This study aimed to investigate the effects of ARNI in HFmrEF patients. Methods: From inception to 15 February 2022, articles were searched via PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, Whip, and Wanfang databases. Left ventricular functions, indicators related to HF, quality of life score, 6-Minute Walk Test, total effective rate, mortality, readmission rate, and adverse events were the outcomes. Relative risk (RR), weighted mean difference (WMD), and 95% confidence interval (CI) were used to evaluate the outcomes. The heterogeneity test was conducted for each indicator and measured by I2 statistics. Subgroup analysis was performed regarding the type of study and duration of treatment. Results: Sixteen studies involving 1,937 patients were included in this study. Our results showed ARNI was likely to improve left ventricular function by increasing the left ventricular ejection fraction (LVEF) (WMD: 2.36, 95%CI: 1.09-3.62), stroke volume (WMD: 16.800, 95%CI: 11.385-22.215), and left ventricular short-axis shortening rate (WMD: 2.05, 95%CI: 0.25-3.86), decreasing left ventricular end-diastolic dimension (WMD: -2.48, 95%CI: -3.83 to -1.13), left atrial diameter (WMD: -2.23, 95%CI: -2.83 to -1.63), C-reactive protein level (WMD: -1.40, 95%CI: -2.62 to -0.18), and N-terminal-pro B-type natriuretic peptide level (WMD: -494.92, 95%CI: -641.34 to -348.50). ARNI has a higher total effective rate (RR: 1.15, 95%CI: 1.08-1.21), Kansas City cardiomyopathy questionnaire (WMD: 4.13, 95%CI: 3.46-4.81), and 6-Minute Walk Test (WMD: 51.35, 95%CI: 26.99-75.71) compared with angiotensin-converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB). In addition, ARNI decreased the readmission rate (RR: 0.54, 95%CI: 0.43-0.68) (all p < 0.05). Nevertheless, there were no significant differences in the adverse outcomes. Conclusion: This meta-analysis suggests ARNI may be an effective strategy with which to improve the left ventricular function, and quality of life, and reduce the readmission rate in HFmrEF patients. However, long-term clinical studies with large samples are still needed to further explore the efficacy and safety of ARNI compared with ACEI or ARB in the HFmrEF population.

Exosomes and Exosomal Cargos: A Promising World for Ventricular Remodeling Following Myocardial Infarction

Exosomes are a pluripotent group of extracellular nanovesicles secreted by all cells that mediate intercellular communications. The effective information within exosomes is primarily reflected in exosomal cargos, including proteins, lipids, DNAs, and non-coding RNAs (ncRNAs), the most intensively studied molecules. Cardiac resident cells (cardiomyocytes, fibroblasts, and endothelial cells) and foreign cells (infiltrated immune cells, cardiac progenitor cells, cardiosphere-derived cells, and mesenchymal stem cells) are involved in the progress of ventricular remodeling (VR) following myocardial infarction (MI) via transferring exosomes into target cells. Here, we summarize the pathological mechanisms of VR following MI, including cardiac myocyte hypertrophy, cardiac fibrosis, inflammation, pyroptosis, apoptosis, autophagy, angiogenesis, and metabolic disorders, and the roles of exosomal cargos in these processes, with a focus on proteins and ncRNAs. Continued research in this field reveals a novel diagnostic and therapeutic strategy for VR.

Investigating the cardioprotective effects of Fuzheng Yangxin recipe based on network pharmacology and experimental evaluation

Background: Under Chinese medicine theory guidance, Fuzheng Yangxin Recipe (FZYX) is clinically effective for the treatment of heart failure (HF) caused by ischemic heart disease (IHD). This study aimed to investigate the mechanism of the myocardial protective effects of FZYX on HF.

Materials and methods: The Gene expression omnibus database was used to identify differential genes of the IHD subtype. Through network pharmacological methods, the targets of the active components of FZYX were obtained. We also constructed IHD-induced HF model rats by ligating the left anterior descending coronary artery. Echocardiography, pathological section staining, enzyme-linked immunosorbent assay, western blotting, immunohistochemistry, and quantitative real-time PCR analyses were performed to verify the protective effects of FZYX on the myocardium.

Results: We identified 53 active components and 37 potential targets of FZYX associated with the IHD subtype. Signal transducer and activator of transcription 3 (STAT3) is a key protein in the protein-protein interaction (PPI) network. A total of 146 biological processes, 10 cellular components and 40 molecular function subcategories were identified by Gene Ontology (GO) enrichment analysis, and 18 signalling pathways, including apoptosis, were identified by Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. In vivo experiments showed that FZYX significantly inhibited cardiomyocyte apoptosis, promoted the expression and phosphorylation of STAT3, and improved cardiac function.

Conclusion: FZXY improves cardiac function and protects cardiomyocytes from injury via multi-component, multi-target and multi-pathway action, especially its possible role in regulating STAT3 expression and anti-apoptotic effect.

Sacubitril Valsartan Enhances Cardiac Function and Alleviates Myocardial Infarction in Rats through a SUV39H1/SPP1 Axis

Sacubitril valsartan (lcz696) has been demonstrated as a substitute for angiotensin-converting enzyme inhibitors and angiotensin receptor blockers for the treatment of heart failure. This research is aimed at examining the effects of lcz696 and its target molecules on myocardial infarction (MI). A rat model of MI was induced by left anterior descending artery ligation and treated with lcz696. Lcz696 treatment significantly reduced cardiac injury and heart failure, restored the left ventricular fractional shortening and ejection fraction, and reduced oxidative stress and inflammatory responses in rat myocardium. By analyzing the heart failure-related GSE47495 dataset and performing gene ontology (GO) functional enrichment analysis, we obtained histone lysine methyltransferase SUV39H1 and secreted phosphoprotein 1 (SPP1) as two molecules implicated in the oxidative stress and inflammation processes. An elevation of SUV39H1 whereas a decline of SPP1 were detected in cardiac tissues after lcz696 treatment. Enrichments of SUV39H1 and H3K9me3 at the SPP1 promoter were identified by chromatin immunoprecipitation assay. SUV39H1 catalyzed H3K9me3 modification to suppress the expression of SPP1. Preconditioning of SUV39H1 silencing blocked the protective roles of lcz696, but SPP1 silencing alleviated the myocardial injury. In conclusion, this study demonstrates that lcz696 enhances cardiac function and alleviates MI in rats through a SUV39H1/SPP1 axis.

Novel Therapies for the Treatment of Cardiac Fibrosis Following Myocardial Infarction

Cardiac fibrosis is a common pathological consequence of most myocardial diseases. It is associated with the excessive accumulation of extracellular matrix proteins as well as fibroblast differentiation into myofibroblasts in the cardiac interstitium. This structural remodeling often results in myocardial dysfunctions such as arrhythmias and impaired systolic function in patients with heart conditions, ultimately leading to heart failure and death. An understanding of the precise mechanisms of cardiac fibrosis is still limited due to the numerous signaling pathways, cells, and mediators involved in the process. This review article will focus on the pathophysiological processes associated with the development of cardiac fibrosis. In addition, it will summarize the novel strategies for anti-fibrotic therapies such as epigenetic modifications, miRNAs, and CRISPR technologies as well as various medications in cellular and animal models.

The impact of Sacubitril/Valsartan on cardiac fibrosis early after myocardial infarction in hypertensive rats

BACKGROUND

Sacubitril/Valsartan, a dual inhibitor of the neprilysin and angiotensin receptor, exerts cardioprotective effects in heart failure. Little is known on the impact of Sacubitril/Valsartan in hypertensive patients early post myocardial infarction.

METHODS

Spontaneously hypertensive rats (SHR) were pretreated by daily angiotensin receptor blocker (ARB; 30 mg/kg intraperitoneally), Sacubitril/Valsartan (ARNI; 60 mg/kg intraperitoneally) or the same dosage of physiological saline for 1 week. Then each group underwent myocardial infarction induction and received the same treatment for another week. The blood pressure and cardiac function were evaluated prior to sacrifice. We performed histological and molecular evaluation of fibrosis in vivo and in vitro.

RESULTS

The blood pressure was comparable between three groups both 1 week prior to and post myocardial infarction. ARNI and ARB restore the decreased ejection fraction (57.3 ± 7.6 vs. 42.9 ± 5.2%, P < 0.05; 54.3 ± 6.9 vs. 42.9 ± 5.2%, P < 0.01, respectively) and fractional shortening (31.6 ± 5.4 vs. 22.1 ± 3.1%, P < 0.05; 29.4 ± 4.5 vs. 22.1 ± 3.1%, P < 0.05, respectively) post myocardial infarction. The infarct size and collagen deposition were also significantly mitigated in ARNI and ARB groups. In addition, ARNI and ARB treatment reduced the expression of cardiac remodeling-related factors, such as Bnp, α-SMA, Vimentin, and Col1a1 (all P < 0.05 vs. MI group). Finally, ARNI and ARB decreased the expression of α-SMA in cardiac fibroblasts treated with Ang II.

CONCLUSION

In conclusion, pretreatment with ARNI maintained cardiac function and reduced myocardial fibrosis in myocardial infarction, probably prior to any anti-hypertensive effect.

Sacubitril/valsartan (LCZ696) ameliorates hyperthyroid-induced cardiac hypertrophy in male rats through modulation of miR-377, let-7 b, autophagy, and fibrotic signaling pathways

Hyperthyroidism is associated with cardiac hypertrophy, fibrosis, and increased risk of cardiovascular mortality. Sacubitril/valsartan (LCZ696) is a new combined drug that has shown promise for the treatment of hyperthyroidism-associated heart failure; however, the underlying molecular mechanisms, including the contributions of epigenetic regulation, remain unclear. The present study was designed to investigate the therapeutic efficacy of LCZ696 and the potential contributions of microRNA regulation in a rat model of hyperthyroidism-induced cardiac hypertrophy. Cardiac hypertrophy was induced by intraperitoneal administration of levothyroxine. Sixty adult male Wistar rats were randomly allocated to four equal groups (15 rats each): control, cardiac hypertrophy (CH), CH + valsartan, and CH + LCZ696. Treatment with LCZ696 or valsartan significantly improved hemodynamic abnormalities, normalized serum concentrations of natriuretic peptide, fibroblast growth factor-23, and cardiac inflammatory markers compared to CH group rats. Treatment with LCZ696 or valsartan also normalized myocardial expression levels of autophagy markers, fibrotic markers, PPAR-ϒ, mir-377, and let-7b. In addition, both valsartan and LCZ696 ameliorated collagen deposition, ventricular degeneration, and various ultrastructural abnormalities induced by levothyroxine. The beneficial effects of LCZ696 were superior to those of valsartan alone. The superior efficacy of LCZ696 may be explained by the stronger modulation of miR-377 and let-7b.

Non-coding RNAs: Important participants in cardiac fibrosis

Cardiac remodeling is a pathophysiological process activated by diverse cardiac stress, which impairs cardiac function and leads to adverse clinical outcome. This remodeling partly attributes to cardiac fibrosis, which is a result of differentiation of cardiac fibroblasts to myofibroblasts and the production of excessive extracellular matrix within the myocardium. Non-coding RNAs mainly include microRNAs and long non-coding RNAs. These non-coding RNAs have been proved to have a profound impact on biological behaviors of various cardiac cell types and play a pivotal role in the development of cardiac fibrosis. This review aims to summarize the role of microRNAs and long non-coding RNAs in cardiac fibrosis associated with pressure overload, ischemia, diabetes mellitus, aging, atrial fibrillation and heart transplantation, meanwhile shed light on the diagnostic and therapeutic potential of non-coding RNAs for cardiac fibrosis.

MALAT1 regulates hypertrophy of cardiomyocytes by modulating the miR-181a/HMGB2 pathway

Noncoding RNAs are important for the regulation of cardiac hypertrophy. The function of MALAT1 (a long noncoding mRNA), miR-181a, and HMGB2, their contribution to cardiac hypertrophy, and the regulatory relationship between them during this process remain unknown. In the present study, we treated primary cardiomyocytes with angiotensin II (Ang II) to mimic cardiac hypertrophy. MALAT1 expression was significantly downregulated in Ang II-treated cardiomyocytes compared with control cardiomyocytes. Ang II-induced cardiac hypertrophy was suppressed by overexpression of MALAT1 and promoted by genetic knockdown of MALAT1. A dual-luciferase reporter assay demonstrated that MALAT1 acted as a sponge for miR-181a and inhibited its expression during cardiac hypertrophy. Cardiac hypertrophy was suppressed by overexpression of an miR-181a inhibitor and enhanced by overexpression of an miR-181a mimic. HMGB2 was downregulated during cardiac hypertrophy and was identified as a target of miR-181a by bioinformatics analysis and a dual-luciferase reporter assay. miR-181a overexpression decreased the mRNA and protein levels of HMGB2. Rescue experiments indicated that MALAT1 overexpression reversed the effect of miR-181a on HMGB2 expression. In summary, the results of the present study show that MALAT1 acts as a sponge for miR-181a and thereby regulates expression of HMGB2 and development of cardiac hypertrophy. The novel MALAT1/miR-181a/HMGB2 axis might play a crucial role in cardiac hypertrophy and serve as a new therapeutic target.

Angiotensin receptor/Neprilysin inhibitor effects in CRTd non-responders: From epigenetic to clinical beside

OBJECTIVES

We evaluated whether Angiotensin receptor/Neprilysin inhibitors (ARNI) reduce heart failure (HF) hospitalizations and deaths in cardiac resynchronization therapy with defibrillator (CRTd) non-responders patients at 12 months of follow-up, modulating microRNAs (miRs) implied in adverse cardiac remodeling.

BACKGROUND

adverse cardiac remodeling characterized by left ventricle ejection fraction (LVEF) reduction, left ventricular end-systolic volume (LVESv) increase, and the 6-minute walking test (6MWT) reduction are relevant pathological mechanisms in CRTd non-responders and could be linked to changes in miRNAs (miRs), regulating cardiac fibrosis, apoptosis, and hypertrophy.

METHODS

miRs levels and clinical outcomes (LVEF, cardiac deaths, and 6MWT) were evaluated at baseline and one year of follow-up in CRTd non-responders divided into ARNI-users and Non-ARNI users.

RESULTS

At baseline, there were no differences in levels of inflammatory markers, miR-18, miR-145, and miR-181 (p > 0.05) between Non-ARNI users (n 106) and ARNI-users (n 312). At one year of follow-up, ARNI-users vs. Non-ARNI users showed lowest inflammatory markers (p < 0.01) and miR-181 levels (p < 0.01) and higher values of miR-18 (p < 0.01)and miR-145 (p < 0.01). At one year of follow-up, ARNI-users had a higher increase of LVEF (p < 0.01) and 6MWT (p < 0.01) along with a more significant reduction of LVESv (p < 0.01) compared to Non-ARNI users. Cox regression analysis evidenced that ARNI-based therapies increase the probability of anti-remodeling effects of CRTd. Based on symptomatic improvements, echocardiographic and functional classification improvements, 37 (34.9%) patients among ARNI-users became responders, while only twenty (6.4%) patients became responders among Non-ARNi-users.

CONCLUSIONS

ARNI might influence epigenetic mechanisms modulating miRs implicated in the adverse cardiac remodeling responses to CRTd.

LncRNA LINC00961 regulates endothelial‑mesenchymal transition via the PTEN‑PI3K‑AKT pathway

The long noncoding RNA LINC00961 plays a crucial role in cancer and cardiovascular diseases. In the present study, the role and underlying mechanism of LINC00961 in endothelial-mesenchymal transition (EndMT) induced by transforming growth factor beta (TGF-β), was investigated. Human cardiac microvascular endothelial cells were transfected with LV-LINC00961 or short hairpin LINC00961 plasmids to overexpress or knock down LINC00961 in the cells, respectively. The cells were then exposed to TGF-β in serum-free medium for 48 h to induce EndMT. Flow cytometric analysis, Cell Counting Kit-8 assay and immunofluorescence staining were performed to examine the cell apoptosis rate, assess cell viability, and identify CD31⁺/α-SMA⁺ double-positive cells, respectively. Western blotting and reverse transcription- quantitative polymerase chain reaction were used to evaluate protein and mRNA expression, respectively. Injury to endothelial cells and EndMT was induced by TGF-β in a time-dependent manner. LINC00961 overexpression promoted injury and EndMT, whereas LINC00961 knockdown had the opposite effects. Knockdown of LINC00961 attenuated EndMT and injury to endothelial cells induced by TGF-β via the PTEN-PI3K-AKT pathway. Inhibition of LINC00961 expression may prevent the occurrence of EndMT-related cardiovascular diseases, such as myocardial fibrosis and heart failure. Therefore, LINC00961 shows potential as a therapeutic target for cardiovascular diseases.

Sacubitril/Valsartan Improves Sexual Function and Fibrosis of the Clitoral and Vaginal Tissues in Female Spontaneously Hypertensive Rats

ABSTRACT

Female sexual dysfunction is common in hypertension. The effects of sacubitril/valsartan (SAC/VAL) as a potential therapy for hypertension and heart failure have not been studied in relation to sexual function and genital fibrosis in female spontaneously hypertensive rats (SHRs). Thirty female SHRs were administered VAL, SAC/VAL, or saline. Ten normotensive female Wistar-Kyoto (WKY) rats were included in the control group. We assessed estrous cyclicity and sexual behavior in the female rats. In addition, the morphology of clitoral and vaginal tissues was evaluated by histological analyses. Western blotting and enzyme-linked immunosorbent assays were used to assess the levels of fibrotic markers in vaginal and clitoral tissues. Furthermore, the protein levels of phosphatase and tensin homolog deleted from chromosome 10 (PTEN), phosphoinositide-3-kinase (PI3K), and AKT expression were measured by Western blotting. SAC/VAL treatment improved hypertension-induced sexual dysfunction, exhibited as a prolonged estrus phase, increased receptivity and proceptive events, and decreased aggressive events, compared with those of VAL treatment and control SHRs without treatments. In addition, SAC/VAL-treated SHRs had lower levels of fibrotic markers, estradiol, and estrogen receptor α/β than the levels of VAL-treated SHRs or SHRs without treatment. Moreover, SAC/VAL decreased p-PTEN expression and increased p-PI3K and p-AKT expression at the protein level compared with those in VAL treatment alone. VAL and SAC/VAL treatments have significantly increased sexual receptivity and proceptivity, decreased aggressiveness, and improved the fibrosis of vaginal and clitoral tissues in female SHRs. However, SAC/VAL treatment shows more effective results compared with VAL treatment, which may be related to the PTEN/PI3K/AKT pathway.

Effects of Sacubitril/Valsartan Versus Telmisartan in Type 2 Diabetic or Pre-Diabetic Patients with Hypertension and Without Heart Failure: The Rationale and Design of A Randomized Clinical Trial

BACKGROUND

Sacubitril/valsartan has revealed superior glycemic and blood pressure control compared with enalapril and irbesartan in patients with heart failure and type 2 diabetes and in individuals with chronic kidney disease. However, whether the effects of sacubitril/valsartan remain the same in those without heart failure is unknown.

METHODS

A multicenter randomized double-blinded trial will be carried out in five military hospitals in Taiwan for a period of 1 year. Participants with prior cardiovascular diseases and heart failure will be excluded. The purpose of the study is to compare the effects of sacubitril/valsartan (97/103 mg once or twice daily) on the temporal changes in fasting blood glucose, HbA1c, insulin resistance and blood pressure levels with telmisartan (40 mg once or twice daily) in individuals with stage 1-3 hypertension and newly diagnosed type 2 diabetes or prediabetes who have an HbA1c ≥6.0% and a systolic blood pressure ≥130 mmHg or a diastolic blood pressure ≥85 mmHg. The inclusion criteria include the age of 35-70 years, women who are not pregnant, estimated glomerular filtration rate ≥45 ml/min per 1.73m2 and B-type natriuretic peptide levels <400 pg/ml.

RESULTS

The sample size is estimated to be 502 participants for randomization according to an assumption of between-person standard deviation in systolic blood pressure of 15 mmHg or in HbA1c of 1.5%, which provides ≥80% power (at p =0.05) to detect a difference in systolic blood pressure of 4 mmHg or in HbA1c of 0.3% at the final follow-up. All participants will receive a comprehensive physical examination and tests for blood cell counts, blood biochemistry, urine analysis, 12-lead electrocardiography and an echocardiography every 3 months.

CONCLUSION

All analyses will be performed based on the intention-to-treat principle among all randomized participants.

Tackling the effects of extracellular vesicles in fibrosis

Fibrosis is a physiological process of tissue repair that turns into pathological when becomes chronic, damaging the functional structure of the tissue. In this review we outline the current status of extracellular vesicles as modulators of the fibrotic process at different levels. In adipose tissue, extracellular vesicles mediate the intercellular communication not only between adipocytes, but also between adipocytes and other cells of the stromal vascular fraction. Thus, they could be altering essential processes for the functionality of adipose tissue, such as adipocyte hypertrophy/hyperplasia, tissue plasticity, adipogenesis and/or inflammation, and ultimately trigger fibrosis. This process is particularly important in obesity, and may eventually, influence the development of obesity-associated alterations. In this regard, obesity is now recognized as an independent risk factor for the development of chronic kidney disease, although the role of extracellular vesicles in this connection has not been explored so far. Nonetheless, the role of extracellular vesicles in the onset and progression of renal fibrosis has been highlighted due to the critical role of fibrosis as a common feature of kidney diseases. In fact, the content of extracellular vesicles disturbs cellular signaling cascades involved in fibrosis in virtually all types of renal cells. What is certain is that the study of extracellular vesicles is complex, as their isolation and manipulation is still difficult to reproduce, which complicates the overview of their physiopathological effects. Nevertheless, new strategies have been developed to exploit the potential of extracellular vesicles and their cargo, both as biomarkers and as therapeutic tools to prevent the progression of fibrosis towards an irreversible event.

Exosomal miRNA-181a-5p from the cells of the hair follicle dermal papilla promotes the hair follicle growth and development via the Wnt/β-catenin signaling pathway

Exosomal miRNAs are verified critical biomarkers, which participate in several biological processes. The growth and development of the hair follicle (HF) are typically controlled by the exosomal miRNAs via cell-to-cell communication. This study identified a high expression of miR-181a-5p in the low-passage DPC-Exos (exosomes derived from dermal papilla cell), revealing the transportation patterns of the DPC-Exos-derived miR-181a-5p entering the HFSC (hair follicle stem cell). The exosomal miR-181a-5p activates the Wnt/β-catenin signaling pathway by targeting the Wnt inhibitor WIF1 and thereby regulates the proteins and genes related to HF growth and development. Moreover, the exosomal miR-181a-5p was found to suppress the HFSC apoptosis but promoted the HFSC proliferation. The in vitro culture of the HF organ revealed that the exosomal miR-181a-5p possesses a positive role in hair growth. Collectively, the exosomal miR-181a-5p affects the HF growth and development through the Wnt/β-catenin signaling pathway. The exosomal miR-181a-5p might, therefore, act as the novel biomarker and therapeutic target for treating hair-related diseases and wool production in mammals.

Modified Exosomes: a Good Transporter for miRNAs within Stem Cells to Treat Ischemic Heart Disease

Stem cell-based therapy for ischemic heart disease (IHD) has become a promising but controversial strategy during the past two decades. The fate and effects of stem cells engrafted into ischemia myocardium are still not fully understood. Stem cell-derived exosomes, a subcategory of extracellular vesicles with nano size, have been considered as an efficient and safe transporter for microRNAs (miRNAs) and a central mediator of the cardioprotective potentials of the parental cells. Hypoxia, pharmacological intervention, and gene manipulation could alter the exosomal miRNAs cargos from stem cells and promote therapeutic potential. Furthermore, several bioengineering methods were also successfully applied to modify miRNAs content and components of exosomal membrane proteins recently. In this review, we outline relevant results about exosomal miRNAs from stem cells and focus on the current strategies to promote their therapeutic efficiency in IHD.

Comparing the efficacy of angiotensin receptor-neprilysin inhibitor and enalapril in acute anterior STEMI patients after primary percutaneous coronary intervention: a prospective randomized trial

BACKGROUND

For patients with heart failure (HF), the effect of angiotensin receptor-neprilysin inhibitors (ARNIs, sacubitril/valsartan) on cardiac remodeling has been found to be superior to angiotensin-converting enzyme inhibitors (ACEI). However, little data have described the impact of early-initiation ARNI in patients with acute anterior ST-segment elevation myocardial infarction (STEMI).

METHODS

In this prospective, randomized, double-blind, parallel-group trial, we enrolled 131 anterior STEMI patients who were treated with primary percutaneous coronary intervention (PCI) between February 2019 and December 2019. All patients received standard STEMI management and were divided into 2 groups (ARNI/enalapril). Primary efficacy outcomes were the between-group difference in change (from baseline to 4-, 12-, and 24-week) in N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentration, left ventricular ejection fraction (LVEF), and left ventricular end-systolic volumes and end-diastolic volumes (LVESV and LVEDV). Secondary outcomes were determined by a composite of death, reinfarction, outpatient HF or HF hospitalization, malignant arrhythmia, and stroke. Safety outcomes included worsening renal function, hypotension, hyperkalemia, angioedema and cough.

RESULTS

We found that NT-proBNP concentration decreased more in the ARNI group than in the enalapril group [4 weeks: ratio of ARNI vs. enalapril 0.36, 95% confidence interval (CI): 0.24 to 0.52, P<0.001; 12 weeks: 0.54, 95% CI: 0.35 to 0.79, P<0.001; 24 weeks: 0.53, 95% CI: 0.32 to 0.83, P<0.001). When compared to the enalapril group, the ARNI group patients had a significant reduction in LVEDV (P<0.001) and LVESV (P<0.001), and an improvement in LVEF (P=0.011) at 24 weeks. Secondary outcomes occurred in 13 participants (20.3%) in the ARNI group and 22 participants (34.4%) in the enalapril group [hazard ratio (HR), 0.56; 95% CI: 0.28 to 1.12; P=0.102]. The incidence of outpatient HF or HF hospitalization in the ARNI group was significantly lower than that in the enalapril group (HR, 0.36; 95% CI: 0.14 to 0.94; P=0.037). There were no significant differences in the safety between the 2 groups.

CONCLUSIONS

For patients with acute anterior STEMI undergoing primary PCI, early initiation of ARNI provided significant clinical benefits.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR2100042944) registered on February 1, 2021.

Huoxue Qianyang Qutan recipe attenuates Ang II-induced cardiomyocyte hypertrophy by regulating reactive oxygen species production

Continuous and irreversible cardiac hypertrophy can induce cardiac maladaptation and cardiac remodeling, resulting in increased risk of developing cardiovascular diseases. The present study was conducted to investigate the therapeutic effect of Huoxue Qianyang Qutan recipe (HQQR) on angiotensin II (Ang II)-induced cardiomyocyte hypertrophy. Primary cardiomyocytes were isolated from the cardiac tissue of neonatal rats, followed by flow cytometry detection to confirm the proportion of primary cardiomyocytes. Cell Counting Kit-8 assay and immunofluorescence detection were performed to examine the effect of Ang II and HQQR on cardiomyocyte hypertrophy. Reactive oxygen species (ROS) and a series of metabolic indicators were quantified to investigate the effect of HQQR on Ang II-induced cardiomyocyte hypertrophy. Mitochondrial electron transport chain complex activity and related coding gene expression were determined to explore the effect of HQQR on mitochondrial function. HQQR significantly inhibited Ang II-induced cardiomyocyte hypertrophy and restored Ang II-induced ROS accumulation, metabolic indicators, and membrane potential levels. HQQR also regulated the mitochondrial function related to the sirtuin 1 pathway in Ang II-induced cardiomyocytes by increasing the activity of the mitochondrial electron transport chain complex and affecting the expression of genes encoding mitochondrial electron transport chain complex subunits. HQQR could alleviate Ang II-induced cardiomyocyte hypertrophy by modulating oxidative stress, accumulating ROS and increasing mitochondrial electron transport chain activity.

Inhibition of DNA methylation in newborns reprograms ischemia-sensitive biomarkers resulting in development of a heart ischemia-sensitive phenotype late in life

Adverse environmental stress exposure at critical perinatal stages can alter cardiovascular development, which could persist into adulthood and develop a cardiovascular dysfunctional phenotype late in life. However, the underlying molecular mechanisms remain largely unknown. The present study provided a direct evidence that DNA methylation is a key epigenetic mechanism contributing to the developmental origins of adult cardiovascular disease. We hypothesized that DNA hypomethylation at neonatal stage alters gene expression patterns in the heart, leading to development of a cardiac ischemia-sensitive phenotype late in life. To test this hypothesis, a DNA methylation inhibitor 5-Aza-2-deoxycytidine (5-Aza) was administered in newborn rats from postnatal day 1-3. Cardiac function and related key genes were measured in 2-week- and 2-month-old animals, respectively. 5-Aza treatment induced an age- and sex-dependent inhibition of global and gene-specific DNA methylation levels in left ventricles, resulting in a long-lasting growth restriction but an asymmetry increase in the heart-to-body weight ratio. In addition, treatment with 5-Aza enhanced ischemia and reperfusion-induced cardiac dysfunction and injury in adults as compared with the saline controls, which was associated with up-regulations of miRNA-181a and angiotensin II receptor type 1 & 2 gene expressions, but down-regulations of PKCε, Atg5, and GSK3β gene expressions in left ventricles. In conclusion, our results provide compelling evidence that neonatal DNA methylation deficiency is a key mechanism contributing to differentially reprogram cardiac gene expression patterns, leading to development of a heart ischemia-sensitive phenotype late in life.

Comparative and Combinatorial Effects of Resveratrol and Sacubitril/Valsartan alongside Valsartan on Cardiac Remodeling and Dysfunction in MI-Induced Rats

The development and progression of heart failure (HF) due to myocardial infarction (MI) is a major concern even with current optimal therapy. Resveratrol is a plant polyphenol with cardioprotective properties. Sacubitril/valsartan is known to be beneficial in chronic HF patients. In this study, we investigated the comparative and combinatorial benefits of resveratrol with sacubitril/valsartan alongside an active comparator valsartan in MI-induced male Sprague Dawley rats. MI-induced and sham-operated animals received vehicle, resveratrol, sacubitril/valsartan, valsartan alone or sacubitril/valsartan + resveratrol for 8 weeks. Echocardiography was performed at the endpoint to assess cardiac structure and function. Cardiac oxidative stress, inflammation, fibrosis, brain natriuretic peptide (BNP), creatinine and neutrophil gelatinase associated lipocalin were measured. Treatment with resveratrol, sacubitril/valsartan, valsartan and sacubitril/valsartan + resveratrol significantly prevented left ventricular (LV) dilatation and improved LV ejection fraction in MI-induced rats. All treatments also significantly reduced myocardial tissue oxidative stress, inflammation and fibrosis, as well as BNP. Treatment with the combination of sacubitril/valsartan and resveratrol did not show additive effects. In conclusion, resveratrol, sacubitril/valsartan, and valsartan significantly prevented cardiac remodeling and dysfunction in MI-induced rats. The reduction in cardiac remodeling and dysfunction in MI-induced rats was mediated by a reduction in cardiac oxidative stress, inflammation and fibrosis.

Exosomal miR-218-5p/miR-363-3p from Endothelial Progenitor Cells Ameliorate Myocardial Infarction by Targeting the p53/JMY Signaling Pathway

Accumulating evidence has shown that endothelial progenitor cell-derived exosomes (EPC-Exos) can ameliorate myocardial fibrosis. The purpose of the present study was to investigate the effects of EPC-Exos-derived microRNAs (miRNAs) on myocardial infarction (MI). A miRNA-Seq dataset of miRNAs differentially expressed between EPCs and exosomes was collected. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to validate the miRNA expression indicated by miRNA-Seq. Immunofluorescence, cell proliferation, and angiogenesis assays were employed to investigate the effects of miRNAs on cardiac fibroblasts (CFs) in vitro. Interactions between miRNAs and their respective targets were examined via immunoblotting, qRT-PCR, and luciferase reporter assays. An MI rat model was constructed, and various staining and immunohistochemical assays were performed to explore the mechanisms underlying the miRNA-mediated effects on MI. miR-363-3p and miR-218-5p were enriched in EPC-Exos, and miR-218-5p and miR-363-3p mimic or inhibitor enhanced or suppressed CF proliferation and angiogenesis, respectively. miR-218-5p and miR-363-3p regulated p53 and junction-mediating and regulatory protein (JMY) by binding to the promoter region of p53 and the 3′ untranslated region of JMY. Additionally, treatment of CFs with Exo-miR-218-5p or Exo-miR-363-3p upregulated p53 and downregulated JMY expression, promoted mesenchymal-endothelial transition, and inhibited myocardial fibrosis. Administration of exosomes containing miR-218-5p mimic or miR-363-3p mimic ameliorated left coronary artery ligation-induced MI and restored myocardial tissue integrity in the MI model rats. In summary, these results show that the protective ability of EPC-Exos against MI was mediated by the shuttled miR-218-5p or miR-363-3p via targeting of the p53/JMY signaling pathway.

Reducing Cardiac Injury during ST-Elevation Myocardial Infarction: A Reasoned Approach to a Multitarget Therapeutic Strategy

The significant reduction in ‘ischemic time’ through capillary diffusion of primary percutaneous intervention (pPCI) has rendered myocardial-ischemia reperfusion injury (MIRI) prevention a major issue in order to improve the prognosis of ST elevation myocardial infarction (STEMI) patients. In fact, while the ischemic damage increases with the severity and the duration of blood flow reduction, reperfusion injury reaches its maximum with a moderate amount of ischemic injury. MIRI leads to the development of post-STEMI left ventricular remodeling (post-STEMI LVR), thereby increasing the risk of arrhythmias and heart failure. Single pharmacological and mechanical interventions have shown some benefits, but have not satisfactorily reduced mortality. Therefore, a multitarget therapeutic strategy is needed, but no univocal indications have come from the clinical trials performed so far. On the basis of the results of the consistent clinical studies analyzed in this review, we try to design a randomized clinical trial aimed at evaluating the effects of a reasoned multitarget therapeutic strategy on the prevention of post-STEMI LVR. In fact, we believe that the correct timing of pharmacological and mechanical intervention application, according to their specific ability to interfere with survival pathways, may significantly reduce the incidence of post-STEMI LVR and thus improve patient prognosis.

Extracellular Vesicles in Organ Fibrosis: Mechanisms, Therapies, and Diagnostics

Fibrosis is the unrelenting deposition of excessively large amounts of insoluble interstitial collagen due to profound matrigenic activities of wound-associated myofibroblasts during chronic injury in diverse tissues and organs. It is a highly debilitating pathology that affects millions of people globally and leads to decreased function of vital organs and increased risk of cancer and end-stage organ disease. Extracellular vesicles (EVs) produced within the chronic wound environment have emerged as important vehicles for conveying pro-fibrotic signals between many of the cell types involved in driving the fibrotic response. On the other hand, EVs from sources such as stem cells, uninjured parenchymal cells, and circulation have in vitro and in vivo anti-fibrotic activities that have provided novel and much-needed therapeutic options. Finally, EVs in body fluids of fibrotic individuals contain cargo components that may have utility as fibrosis biomarkers, which could circumvent current obstacles to fibrosis measurement in the clinic, allowing fibrosis stage, progression, or regression to be determined in a manner that is accurate, safe, minimally-invasive, and conducive to repetitive testing. This review highlights the rapid and recent progress in our understanding of EV-mediated fibrotic pathogenesis, anti-fibrotic therapy, and fibrosis staging in the lung, kidney, heart, liver, pancreas, and skin.

Sacubitril/Valsartan Decreases Atrial Fibrillation Susceptibility by Inhibiting Angiotensin II-Induced Atrial Fibrosis Through p-Smad2/3, p-JNK, and p-p38 Signaling Pathways

Sacubitril/valsartan (SAC/VAL) prevents angiotensin II (AngII) from binding AT1-R and blocks degradation of natriuretic peptides. Despite its efficacy in reducing ventricular fibrosis and preserving cardiac functions, which has been extensively demonstrated in myocardial infarction or pressure overload models, few studies have been conducted to determine whether SAC/VAL could attenuate atrial fibrosis and decrease atrial fibrillation (AF) susceptibility. Our study provided evidence for the inhibition of atrial fibrosis and reduced susceptibility to AF by SAC/VAL. After 28 days of AngII continuous subcutaneous stimulation, rats in SAC/VAL group exhibited reduced extent of atrial fibrosis, inhibited proliferation, migration, and differentiation of atrial fibroblasts, and decreased susceptibility to AF. We further found that inhibition of p-Smad2/3, p-JNK, and p-p38MAPK pathways is involved in the role of SAC/VAL on AngII-induced atrial fibrosis in vivo. These results emphasize the importance of SAC/VAL in the prevention of AngII-induced atrial fibrosis and may help to enrich the options for AF pharmacotherapy.

Protective Effects of Sacubitril/Valsartan on Cardiac Fibrosis and Function in Rats With Experimental Myocardial Infarction Involves Inhibition of Collagen Synthesis by Myocardial Fibroblasts Through Downregulating TGF-β1/Smads Pathway

Objectives: To investigate the effect and mechanism of sacubitril/valsartan on myocardial fibrosis in rats following experimental myocardial infarction and in TGF-β1-treated myocardial fibroblasts.

Methods: Male Sprague-Dawley (SD) rats were subjected to coronary artery ligation to establish myocardial infarction and intragastrically fed vehicle, valsartan (Val, 32 mg/kg, once-daily) or sacubitril/valsartan (Sac/Val, 68 mg/kg, once-daily) for 4 weeks. In parallel, myocardial fibroblasts (MFs) isolated from neonatal SD rats were exposed to hypoxia and treated with TGF-β1 (5 ng/ml) plus vehicle, Val (10⁷–10^–5 M) or Sac/Val (10⁷–10⁵ M). Rat cardiac function and fibrosis were measured by echocardiography and histological method, respectively. MFs viability and collagen synthesis were determined by cell counting kit-8 and enzyme-linked immunosorbent assay, respectively. Protein expressions of TGF-β1, Smad3, phosphorylated Smad3 (p-Smad3), and p-Smad3 subcellular localization were detected by immunoblotting and immunocytochemistry.

Results: Sac/Val significantly improved cardiac structure and function in rats after myocardial infarction, including decreased left ventricular end-diastolic diameter and interventricular septal thickness, increased ejection fraction, and reduced myocardial collagen volume fraction and type Ⅰ and type Ⅲ collagen levels, and this effect was superior to that of Val. Besides, Sac/Val inhibited myocardial TGF-β1 and p-Smad3 protein expression better than Val. Mechanically, Sac/Val significantly attenuated TGF-β1-induced proliferation and collagen synthesis of MFs, and inhibit Smad3 phosphorylation and nucleus translocation, and this effect outperformed Val. Overexpression and silencing of Smad3 enhanced and reversed the inhibitory effects of Sac/Val on TGF-β1-induced collagen synthesis by MFs, respectively.

Conclusions: Sacubitril/valsartan improves cardiac function and fibrosis in rats after experimental myocardial infarction, and this effect is related to the inhibition of collagen synthesis in myocardial fibroblasts by inhibiting the TGF/Smads signaling pathway.

A Brief Review on the Biology and Effects of Cellular and Circulating microRNAs on Cardiac Remodeling after Infarction

Despite advances in diagnostic, prognostic, and treatment modalities, myocardial infarction (MI) remains a leading cause of morbidity and mortality. Impaired cellular signaling after an MI causes maladaptive changes resulting in cardiac remodeling. MicroRNAs (miRNAs/miR) along with other molecular components have been investigated for their involvement in cellular signaling in the pathogenesis of various cardiac conditions like MI. miRNAs are small non-coding RNAs that negatively regulate gene expression. They bind to complementary mRNAs and regulate the rate of protein synthesis by altering the stability of their targeted mRNAs. A single miRNA can modulate several cellular signaling pathways by targeting hundreds of mRNAs. This review focuses on the biogenesis and beneficial effects of cellular and circulating (exosomal) miRNAs on cardiac remodeling after an MI. Particularly, miR-1, -133, 135, and -29 that play an essential role in cardiac remodeling after an MI are described in detail. The limitations that will need to be addressed in the future for the further development of miRNA-based therapeutics for cardiovascular conditions will also be discussed.

Myocardial Infarction: The Protective Role of MiRNAs in Myocardium Pathology

Cardiovascular diseases have been regarded as the leading cause of death around the world, with myocardial infarction (MI) being the most severe form. MI leads to myocardial apoptosis, cardiomyocyte fibrosis, and cardiomyocyte hypertrophy, ultimately leading to heart failure, and death. Micro RNAs (miRNAs) participate in the genesis and progression of myocardial pathology after MI by playing an important regulatory role. This review aims to summarize all available knowledge on the role of miRNAs in the myocardial pathological process after MI to uncover potential major target pathways. In addition, the main therapeutic methods and their latest progress are also reviewed. miRNAs can regulate the main signaling pathways as well as pathological processes. Thus, they have the potential to induce therapeutic effects. Hence, the combination of miRNAs with recently developed exosome nanocomplexes may represent the future direction of therapeutics.

Sacubitril/Valsartan Reduces Fibrosis and Alleviates High-Salt Diet-Induced HFpEF in Rats

Previous studies have confirmed the clinical efficacy of sacubitril/valsartan (Sac/Val) for the treatment of heart failure with reduced ejection fraction (HFrEF). However, the role of Sac/Val in heart failure with preserved ejection fraction (HFpEF) remains unclear. Sac/Val is a combination therapeutic medicine comprising sacubitril and valsartan that acts as a first angiotensin receptor blocker and neprilysin inhibitor (angiotensin-receptor neprilysin inhibitor (ARNI)). Here, we investigated the role of Sac/Val in high-salt diet-induced HFpEF coupled with vascular injury as well as the underlying mechanism. Rats were fed with high-salt feed, followed by intragastric administration of Sac/Val (68 mg/kg; i.g.). The results of functional tests revealed that a high-salt diet caused pathological injuries in the heart and vascular endothelium, which were significantly reversed by treatment with Sac/Val. Moreover, Sac/Val significantly decreased the levels of fibrotic factors, including type I collagen and type Ⅲ collagen, thus, reducing the ratio of MMP2/TIMP2 while increasing Smad7 levels. Further investigation suggested that Sac/Val probably reversed the effects of high-salt diet-induced HFpEF by inhibiting the activation of the TGF-β1/Smad3 signaling pathway. Thus, treatment with Sac/Val effectively alleviated the symptoms of high-salt diet-induced HFpEF, probably by inhibiting fibrosis via the TGF-β1/Smad3 signaling pathway, supporting the therapeutic potential of Sac/Val for the treatment of HFpEF.

Reprogramming of miR-181a/DNA methylation patterns contribute to the maternal nicotine exposure-induced fetal programming of cardiac ischemia-sensitive phenotype in postnatal life

Background: E-cigarette and other novel electronic nicotine delivery systems (ENDS) have recently entered the market at a rapid pace. The community desperately needs answers about the health effects of ENDS. The present study tested the hypothesis that perinatal nicotine exposure (PNE) causes a gender-dependent increase in vulnerability of the heart to ischemia-reperfusion (I/R) injury and cardiac dysfunction in male rat offspring via reprogramming of the miRNA-181a (miR-181a)-mediated signaling pathway and that miR-181a antisense could rescue this phenotype. Methods: Nicotine or saline was administered to pregnant rats via subcutaneous osmotic minipumps from gestational day 4 until postnatal day 10. Cardiac function and molecular biological experiments were conducted in ~3- month-old offspring. Results: PNE enhanced I/R-induced cardiac dysfunction and infarction in adult male but not in female offspring, which was associated with miR-181a over-expression in left ventricle tissues. In addition, PNE enhanced offspring cardiac angiotensin receptor (ATR) expressions via specific CpG hypomethylation of AT₁R/AT₂R promoter. Furthermore, PNE attenuated cardiac lncRNA H19 levels, but up-regulated cardiac TGF-β/Smads family proteins and consequently up-regulated autophagy-related protein (Atg-5, beclin-1, LC3 II, p62) expression in the male offspring. Of importance, treatment with miR-181a antisense eliminated the PNE's effect on miR-181a expression/H19 levels and reversed PNE-mediated I/R-induced cardiac infarction and dysfunction in male offspring. Furthermore, miR-181a antisense also attenuated the effect of PNE on AT₁R/AT₂R/TGF-β/Smads/autophagy-related biomarkers in the male offspring. Conclusion: Our data suggest that PNE could induce a reprogramming of cardiac miR-181a expression/DNA methylation pattern, which epigenetically modulates ATR/TGF-β/autophagy signaling pathways, leading to gender-dependent development of ischemia-sensitive phenotype in postnatal life. Furthermore, miR-181a could severe as a potential therapeutic target for rescuing this phenotype.

Sacubitril/Valsartan Improves Cardiac Function and Decreases Myocardial Fibrosis Via Downregulation of Exosomal miR-181a in a Rodent Chronic Myocardial Infarction Model

Background Exosomes are small extracellular vesicles that function as intercellular messengers and effectors. Exosomal cargo contains regulatory small molecules, including miRNAs, mRNAs, lncRNAs, and small peptides that can be modulated by different pathological stimuli to the cells. One of the main mechanisms of action of drug therapy may be the altered production and/or content of the exosomes. Methods and Results We studied the effects on exosome production and content by neprilysin inhibitor/angiotensin receptor blockers, sacubitril/valsartan and valsartan alone, using human-induced pluripotent stem cell-derived cardiomyocytes under normoxic and hypoxic injury model in vitro, and assessed for physiologic correlation using an ischemic myocardial injury rodent model in vivo. We demonstrated that the treatment with sacubitril/valsartan and valsartan alone resulted in the increased production of exosomes by induced pluripotent stem cell-derived cardiomyocytes in vitro in both conditions as well as in the rat plasma in vivo. Next-generation sequencing of these exosomes exhibited downregulation of the expression of rno-miR-181a in the sacubitril/valsartan treatment group. In vivo studies employing chronic rodent myocardial injury model demonstrated that miR-181a antagomir has a beneficial effect on cardiac function. Subsequently, immunohistochemical and molecular studies suggested that the downregulation of miR-181a resulted in the attenuation of myocardial fibrosis and hypertrophy, restoring the injured rodent heart after myocardial infarction. Conclusions We demonstrate that an additional mechanism of action of the pleiotropic effects of sacubitril/valsartan may be mediated by the modulation of the miRNA expression level in the exosome payload.