Ameliorate Heart Failure Research Articles

Effects of empagliflozin on cardio-renal interaction in heart failure with reduced ejection fraction: results from in-vivo experiments and the CINNAMON-study

Abstract Background Heart failure is often accompanied by renal dysfunction, which indicates a pathophysiological connection between the heart and kidneys. Empagliflozin, a SGLT2 inhibitor, showed beneficial effects on both cardiovascular and renal endpoints. Mechanistically, however, it is unclear whether the empagliflozin-dependent renal protection is mediated via the inhibition of renal SGLT2 or rather indirectly via improved cardiac function. Interestingly, in the EMPEROR trials, there was a significant interaction of empagliflozin-dependent kidney protection with systolic contractile dysfunction. We hypothesized that Empagliflozin treatment ameliorates heart failure in response to chronic pressure overload in mice leading to improved renal function. We correlated these findings with data from our prospective, single-armed trial. Methods Transverse aortic constriction (TAC) or sham surgery was performed in C57BL/6J (wildtype, WT) and SGLT2 deficient mice (SGLT2-/-). Animals received either Empagliflozin (10 mg/kg bodyweight) or vehicle by daily oral gavage. Cardiac function was evaluated by echocardiography and kidney function by transdermal FITC-Sinistrin measurement (GFR), urinary albumin/creatinine ratio (UACR) and Siriusred fibrosis staining. Results After 10 weeks, echocardiography confirmed TAC induced pressure-overload, leading to reduced left ventricular ejection fraction (LVEF) and diastolic dysfunction. Empagliflozin attenuated changes in LVEF (Fig. A) and improved diastolic dysfunction (data not shown). Interestingly, at 10 weeks, TAC reduced GFR, increased UACR and tended to increase renal fibrosis, which was attenuated by empagliflozin (Fig. B, C and D). To test if direct inhibition of SGLT2 in the heart and kidney is mechanistically involved, TAC surgery was repeated in SGLT2-deficient mice (SGLT2-/-). In fact, exposure to TAC resulted in comparable reduction of LVEF in SGLT2-/- mice and Empagliflozin prevented this deterioration similar to WT mice (Fig. E vs. A). Surprisingly, Empagliflozin also prevented GFR deterioration 10 weeks after TAC in mice lacking SGLT2 (SGLT2-/-) with comparable magnitude as in WT mice (Fig. F), suggesting that the reno-protective effect of Empagliflozin was independent from renal SGLT2 inhibition. The effect of empagliflozin on the heart and kidney was also investigated in patients with HF (prospective, single-arm CINNAMON-study, DRKS00031101). After 180 days of Empagliflozin treatment (10 mg), there was a significant improvement in LVEF, NT-proBNP levels and KCCQ-12 Scores (Fig. G-I) and the effects on UACR and GFR are subject of investigation. Conclusion This is the first study investigating the role of SGLT2 in Empagliflozin-dependent kidney protection of mice that develop heart failure after TAC. Importantly, empagliflozin treatment prevented deterioration of LVEF and GFR independent of the presence of SGLT2 in mice and improved cardiac markers and quality of life in patients.

Chromatin remodelling drives immune cell-fibroblast communication in heart failure.

Chronic inflammation and tissue fibrosis are common responses that worsen organ function, yet the molecular mechanisms governing their cross-talk are poorly understood. In diseased organs, stress-induced gene expression changes fuel maladaptive cell state transitions1 and pathological interaction between cellular compartments. Although chronic fibroblast activation worsens dysfunction in the lungs, liver, kidneys and heart, and exacerbates many cancers2, the stress-sensing mechanisms initiating transcriptional activation of fibroblasts are poorly understood. Here we show that conditional deletion of the transcriptional co-activator Brd4 in infiltrating Cx3cr1+ macrophages ameliorates heart failure in mice and significantly reduces fibroblast activation. Analysis of single-cell chromatin accessibility and BRD4 occupancy in vivo in Cx3cr1+ cells identified a large enhancer proximal to interleukin-1β (IL-1β, encoded by Il1b), and a series of CRISPR-based deletions revealed the precise stress-dependent regulatory element that controls Il1b expression. Secreted IL-1β activated a fibroblast RELA-dependent (also known as p65) enhancer near the transcription factor MEOX1, resulting in a profibrotic response in human cardiac fibroblasts. In vivo, antibody-mediated IL-1β neutralization improved cardiac function and tissue fibrosis in heart failure. Systemic IL-1β inhibition or targeted Il1b deletion in Cx3cr1+ cells prevented stress-induced Meox1 expression and fibroblast activation. The elucidation of BRD4-dependent cross-talk between a specific immune cell subset and fibroblasts through IL-1β reveals how inflammation drives profibrotic cell states and supports strategies that modulate this process in heart disease and other chronic inflammatory disorders featuring tissue remodelling.

Peptide-Amphiphilic Nanoassemblies as a Responsive Senolytic Navigator for Targeted Removal of Senescent Cardiomyocytes to Ameliorate Heart Failure.

Heart failure (HF) represents the terminal stage of numerous cardiovascular disorders and lacks effective therapeutic strategies. The accumulation of senescent cardiomyocytes is a cardinal characteristic of HF, contributing to myocardial dysfunction and deteriorating the myocardial microenvironment through the development of senescence-associated secretory phenotypes (SASPs), ultimately culminating in pathological remodeling. Senolytics, a promising therapeutic strategy that selectively induces apoptosis in senescent cells, faces challenges due to nonspecific effects, raising concerns for clinical implementation. In this study, we developed peptide-amphiphilic nanoassemblies as responsive drug navigators for targeted delivery. The modular nanoassemblies comprise a hydrophilic domain containing a CD9-binding peptide, a hydrophobic domain incorporating a reactive oxygen species (ROS)-responsive motif, and an alkyl tail for encapsulation of the senolytic ABT263. The CD9-targeted and ROS-responsive nanoassemblies (AP@ABT263) specifically recognized senescent cardiomyocytes and modulated the release of ABT263 in the presence of elevated intracellular ROS levels. AP@ABT263 treatment significantly enhanced the targeted delivery of ABT263 to senescent cells in both in vitro and in vivo while showing minimal toxicity to normal cardiomyocytes and other tissues. Our findings provide compelling evidence that AP@ABT263 efficiently eradicated senescent cardiomyocytes, enhanced cardiac function, and attenuated the deleterious effects of SASP, thereby preventing adverse cardiac remodeling. In summary, AP@ABT263 represents a highly promising approach for responsive and controlled drug release in senescent cardiomyocytes, providing valuable insights into the development of intelligent pharmaceutical interventions for the management of HF.

Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) Ameliorate Heart Failure through Reductions in Oxidative Stress: A Systematic Review and Meta-Analysis.

The objectives of this study were to explore the role that eicosapentaenoic acid (EPA) and/or docosahexaenoic acid (DHA) plays in heart failure (HF), highlighting the potential connection to oxidative stress pathways. Following PRISMA guidelines, we conducted electronic searches of the literature in MEDLINE and EMBASE focusing on serum EPA and/or DHA and EPA and/or DHA supplementation in adult patients with heart failure or who had heart failure as an outcome of this study. We screened 254 studies, encompassing RCTs, observational studies, and cohort studies that examined HF outcomes in relation to either serum concentrations or dietary supplementation of EPA and/or DHA. The exclusion criteria were pediatric patients, non-HF studies, abstracts, editorials, case reports, and reviews. Eleven studies met our criteria. In meta-analyses, high serum concentrations of DHA were associated with a lower rate of heart failure with a hazard ratio of 0.74 (CI = 0.59-0.94). High serum concentrations of EPA also were associated with an overall reduction in major adverse cardiovascular events with a hazard ratio of 0.60 (CI = 0.46-0.77). EPA and DHA, or n3-PUFA administration, were associated with an increased LVEF with a mean difference of 1.55 (CI = 0.07-3.03)%. A potential explanation for these findings is the ability of EPA and DHA to inhibit pathways by which oxidative stress damages the heart or impairs cardiac systolic or diastolic function producing heart failure. Specifically, EPA may lower oxidative stress within the heart by reducing the concentration of reactive oxygen species (ROS) within cardiac tissue by (i) upregulating nuclear factor erythroid 2-related factor 2 (Nrf2), which increases the expression of antioxidant enzyme activity, including heme oxygenase-1, thioredoxin reductase 1, ferritin light chain, ferritin heavy chain, and manganese superoxide dismutase (SOD), (ii) increasing the expression of copper-zinc superoxide dismutase (MnSOD) and glutathione peroxidase, (iii) targeting Free Fatty Acid Receptor 4 (Ffar4), (iv) upregulating expression of heme-oxygenase-1, (v) lowering arachidonic acid levels, and (vi) inhibiting the RhoA/ROCK signaling pathway. DHA may lower oxidative stress within the heart by (i) reducing levels of mitochondrial-fission-related protein DRP-1(ser-63), (ii) promoting the incorporation of cardiolipin within the mitochondrial membrane, (iii) reducing myocardial fibrosis, which leads to diastolic heart failure, (iv) reducing the expression of genes such as Appa, Myh7, and Agtr1α, and (v) reducing inflammatory cytokines such as IL-6, TNF-α. In conclusion, EPA and/or DHA have the potential to improve heart failure, perhaps mediated by their ability to modulate oxidative stress.

Ginsenoside Rb1 ameliorates heart failure through DUSP-1-TMBIM-6-mediated mitochondrial quality control and gut flora interactions

BackgroundThere is currently no specific therapeutic drug available for heart failure in clinical practice. Numerous studies have validated the efficacy of Ginsenoside Rb1, an active component found in various herbal remedies used for heart failure treatment, in effectively ameliorating myocardial ischemia. However, the precise mechanism of action and molecular targets of Ginsenoside Rb1 remain unclear. PurposeThis study aims to explore the molecular mechanisms through which Ginsenoside Rb1 synergistically modulates the gut flora and mitochondrial quality control network in heart failure by targeting the DUSP-1-TMBIM-6-VDAC1 axis. Study designThis study utilized DUSP-1/VDAC1 knockout (DUSP-1-/-/VDAC1-/-) and DUSP-1/VDAC1 transgenic (DUSP-1+/+/VDAC1+/+) mouse models of heart failure, established through Transverse Aortic Constriction (TAC) surgery and genetic modification techniques. The mice were subsequently subjected to treatment with Ginsenoside Rb1. MethodsA series of follow-up multi-omics analyses were conducted, including assessments of intestinal flora, gene transcription sequencing, single-cell databases, and molecular biology assays of primary cardiomyocytes, to investigate the mechanism of action of Ginsenoside Rb1. ResultsGinsenoside Rb1 was found to have multiple regulatory mechanisms on mitochondria. Notably, DUSP-1 was discovered to be a crucial molecular target of Ginsenoside Rb1, controlling both intestinal flora and mitochondrial function. The regulatory effects of DUSP-1 on inflammation and mitochondrial quality control were mediated by changes in TMBIM-6 and VDAC1. Furthermore, NLRP3-mediated inflammatory responses were found to interact with mitochondrial quality control, exacerbating myocardial injury under stress conditions. Ginsenoside Rb1 modulated the DUSP-1-TMBIM-6-VDAC1 axis, inhibited the release of pro-inflammatory factors, altered the structural composition of the gut flora, and protected impaired heart function. These effects indirectly influenced the crosstalk between inflammation, mitochondria, and gut flora. ConclusionThe DUSP-1-TMBIM-6-VDAC1 axis, an upstream pathway regulated by Ginsenoside Rb1, is a profound mechanism through which Ginsenoside Rb1 improves cardiac function in heart failure by modulating inflammation, mitochondria, and gut flora.

Gene therapy with phosphodiesterases 2A and 4B ameliorates heart failure and arrhythmias by improving subcellular cAMP compartmentation.

Gene therapy with cardiac phosphodiesterases (PDEs), such as phosphodiesterase 4B (PDE4B), has recently been described to effectively prevent heart failure (HF) in mice. However, exact molecular mechanisms of its beneficial effects, apart from general lowering of cardiomyocyte cyclic adenosine monophosphate (cAMP) levels, have not been elucidated. Here, we studied whether gene therapy with two types of PDEs, namely PDE2A and PDE4B, can prevent pressure-overload-induced HF in mice by acting on and restoring altered cAMP compartmentation in distinct subcellular microdomains. HF was induced by transverse aortic constriction followed by tail-vein injection of adeno-associated-virus type 9 vectors to overexpress PDE2A3, PDE4B3, or luciferase for 8 weeks. Heart morphology and function was assessed by echocardiography and histology which showed that PDE2A and especially PDE4B gene therapy could attenuate cardiac hypertrophy, fibrosis, and decline of contractile function. Live cell imaging using targeted cAMP biosensors showed that PDE overexpression restored altered cAMP compartmentation in microdomains associated with ryanodine receptor type 2 (RyR2) and caveolin-rich plasma membrane. This was accompanied by ameliorated caveolin-3 decline after PDE2A3 overexpression, reduced RyR2 phosphorylation in PDE4B3 overexpressing hearts, and antiarrhythmic effects of both PDEs measured under isoproterenol stimulation in single cells. Strong association of overexpressed PDE4B but not PDE2A with RyR2 microdomain could prevent calcium leak and arrhythmias in human-induced pluripotent stem-derived cardiomyocytes with the A2254V mutation in RyR2 causing catecholaminergic polymorphic ventricular tachycardia. Our data indicate that gene therapy with phosphodiesterases can prevent HF including associated cardiac remodelling and arrhythmias by restoring altered cAMP compartmentation in functionally relevant subcellular microdomains.

Chlorogenic acid ameliorates heart failure by attenuating cardiomyocyte ferroptosis

ObjectiveTo elucidate the effects of chlorogenic acid (CGA), a bioactive polyphenol compound prevalent in traditional Chinese medicine and various foods, including Lonicera japonica Thunb. (Jin Yin Hua), Eucommia ulmoides Oliv. (Du Zhong Ye), tea, and coffee, on cardiomyocyte ferroptosis and heart failure. MethodsWe assessed the effect of CGA on cardiac function using a mouse model of heart failure induced by transverse aortic constriction (TAC). These indicators included the left ventricular ejection fraction (LVEF), fractional shortening (LVFS), end-systolic volume (LVESV), end-diastolic volume (LVEDV), end-systolic diameter (LVESD), and end-diastolic diameter (LVEDD). An isoprenaline hydrochloride (ISO)-induced H9c2 cardiomyocyte cell model was also established, and the cells were treated with various concentrations of CGA. To assess the effect of CGA on ferroptosis in cardiomyocytes, we measured cell viability and evaluated the levels of intracellular reactive oxygen species (ROS), ferrous ions (Fe2+), and lipid peroxidation using fluorescent staining. To clarify the ferroptosis signaling pathway regulated by CGA, western blotting was used to examine the expression of ferroptosis biomarkers, specifically solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4), in H9c2 cardiomyocytes and mouse myocardial tissues. ResultsCGA significantly enhanced cardiac performance indices such as LVEF, LVFS, LVESV, LVEDV, LVESD, and LVEDD. H9c2 cardiomyocytes exposed to ISO showed decreased cell viability and increased ROS levels, Fe2+ content, and lipid peroxidation levels. However, CGA treatment significantly ameliorated these changes. Additionally, in both H9c2 cardiomyocytes and myocardial tissue obtained from mice with TAC, CGA increased the expression of ferroptosis-related proteins, including SLC7A11 and GPX4. ConclusionCGA has the potential to enhance cardiac function and diminish lipid peroxidation and ROS levels in cardiomyocytes via the SLC7A11/GPX4 signaling pathway. This process alleviates ferroptosis in cardiomyocytes. These results provide new insights into the clinical use of CGA and the management of heart failure.

PPARδ activation improves cardiac mitochondrial homeostasis in desmin deficient mice but does not alleviate systolic dysfunction

Peroxisome proliferator-activated receptor (PPAR) δ is a major transcriptional regulator of cardiac energy metabolism with pleiotropic properties, including anti-inflammatory, anti-oxidative and cardioprotective action. In this study, we sought to investigate whether pharmacological activation of PPARδ via intraperitoneal administration of the selective ligand GW0742 could ameliorate heart failure and mitochondrial dysfunction that have been previously reported in a characterized genetic model of heart failure, the desmin null mice (Des−/−). Our studies demonstrate that treatment of Des−/− mice with the PPARδ agonist attenuated cardiac inflammation, fibrosis and cardiac remodeling. In addition, PPARδ activation alleviated oxidative stress in the failing myocardium as evidenced by decreased ROS levels. Importantly, PPARδ activation stimulated mitochondrial biogenesis, prevented mitochondrial and sarcoplasmic reticulum vacuolar degeneration and improved the mitochondrial intracellular distribution. Finally, PPARδ activation alleviated the mitochondrial respiratory dysfunction, prevented energy depletion and alleviated excessive autophagy and mitophagy in Des−/− hearts. Nevertheless, improvement of all these parameters did not suffice to overcome the significant structural deficiencies that desmin deletion incurs in cardiomyocytes and cardiac function did not improve significantly. In conclusion, pharmacological PPARδ activation in Des−/− hearts exerts protective effects during myocardial degeneration and heart failure by preserving the function and quality of the mitochondrial network. These findings implicate PPARδ agonists as a supplemental constituent of heart failure medications.

Abstract P2058: Mesenchymal Stem Cells Reduce Endothelin-1 Induced Hypertrophy In Hypoplastic Left Heart Syndrome Patients’ Cardiomyocytes

Introduction: Hypoplastic left heart syndrome (HLHS) is one of the most difficult congenital cardiovascular conditions. There are no proven therapeutic strategies for systemic right ventricular (RV) heart failure till now. Hypothesis: We investigated whether mesenchymal stem cells (MSCs) can ameliorate heart failure (HF) in HLHS patients. Methods & Results: We analyzed the cardiac tissues of patients with HLHS (N = 20) and healthy donors (N = 12). Compared to the controls, the cross-sectional area of cardiomyocytes determined by wheat germ agglutinin staining significantly increased in the HLHS hearts. Furthermore, quantitative RT-PCR (qRT-PCR) confirmed the expression of fetal genes, including atrial natriuretic factor (ANF), natriuretic peptide B (BNP), and myosin heavy chain-β (MHC-β), were significantly upregulated in the HLHS. The results indicated severe pathological hypertrophy in HLHS patients. To investigate our hypothesis, we employed HLHS patients’ iPSCs and differentiated them into cardiomyocytes (iCMs). Differentiated HLHS-iCMs were confirmed by expression of the cardiac markers, cardiac troponin T. In vitro , 10nM Endothelin-1 (ET-1) stimulation successfully induced cardiac hypertrophy confirmed by cell size and fetal gene expression. Interestingly, co-cultured HLHS-iCMs with mesenchymal stem cells (MSCs) in the trans-well plates reduced the ET-1 induced hypertrophy. The results indicated that secretome from MSCs played a critical role in referring to the anti-hypertrophic effects. Compared to the control conditioned media from fibroblasts, GDF-15 was highly expressed in the MSC-conditioned medium. GDF-15 alone also reduced ET-1 induced hypertrophy in the HLHS-iCMs. Conclusions: In HLHS patients, RV hypertrophy is a hallmark of heart failure. MSCs potentially inhibited hypertrophic remodeling in HLHS patient-specific cardiomyocytes through beneficial secretomes, such as GDF-15.

Oral administration of vancomycin alleviates heart failure triggered by chronic kidney disease

Chronic kidney disease (CKD) induces an imbalance in the intestinal microbiota, affecting various physiological functions and leading to cardiovascular inflammation and fibrosis. However, the cardiotoxic impact of intestinal microbiota-derived uremic substances in advanced renal dysfunction remains unexplored. Therefore, we developed a 5/6 nephrectomy (5/6Nx) mouse model to investigate the intestinal microbiota and the effects of administering vancomycin (VCM) on the microbiota and the cardiac pathology associated with CKD. Despite VCM administration after the development of irreversible glomerulosclerosis and tubulointerstitial fibrosis, blood indoxyl sulfate and phenyl sulfate levels, which are intestinal bacteria-derived uremic substances, brain natriuretic peptide levels, and the fibrotic area in the heart were decreased. Moreover, VCM administration prevented 5/6Nx-induced weight loss and prolonged survival time. Our findings suggest that VCM-induced changes in the intestinal microbiota composition ameliorate heart failure and improve survival rates by reducing intestinal microbiota-derived cardiotoxic substances despite advanced renal dysfunction. This highlights the potential of using the intestinal microbiota as a target to prevent and treat cardiovascular conditions associated with CKD.

Novel pterostilbene derivatives ameliorate heart failure by reducing oxidative stress and inflammation through regulating Nrf2/NF-κB signaling pathway

Pterostilbene is a demethylated resveratrol derivative with attractive anti-inflammatory, anti-tumor and anti-oxidative stress activities. However, the clinical use of pterostilbene is limited by its poor selectivity and druggability. Heart failure is a leading cause of morbidity and mortality worldwide, which is closely related to enhanced oxidative stress and inflammation. There is an urgent need for new effective therapeutic drugs that can reduce oxidative stress and inflammatory responses. Therefore, we designed and synthesized a series of novel pterostilbene chalcone and dihydropyrazole derivatives with antioxidant and anti-inflammatory activities by the molecular hybridization strategy. The preliminary anti-inflammatory activities and structure-activity relationships of these compounds were evaluated by nitric oxide (NO) inhibitory activity in lipopolysaccharide (LPS)-treated RAW264.7 cells, and compound E1 exhibited the most potent anti-inflammatory activities. Furthermore, pretreatment with compound E1 decreased reactive oxygen species (ROS) generation both in RAW264.7 and H9C2 cells by increasing the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), as well as downstream antioxidant enzymes superoxide dismutase 1 (SOD1), catalase (CAT) and glutathione peroxidase 1 (GPX1). In addition, compound E1 also significantly inhibited LPS or doxorubicin (DOX)-induced inflammation in both RAW264.7 and H9C2 cells through reducing the expression of inflammatory cytokines by inhibiting nuclear factor-κB (NF-κB) signaling pathway. Moreover, we found that compound E1 improved DOX-induced heart failure by inhibiting inflammation and oxidative stress in mouse model, which is mediated by the potential of antioxidant and anti-inflammatory activities. In conclusion, this study demonstrated the novel pterostilbene dihydropyrazole derivative E1 was identified as a promising agent for heart failure treatment.

6-Shogaol, an Active Component of Ginger, Inhibits p300 Histone Acetyltransferase Activity and Attenuates the Development of Pressure-Overload-Induced Heart Failure.

Hypertrophic stress-induced cardiac remodeling is a compensatory mechanism associated with cardiomyocyte hypertrophy and cardiac fibrosis. Continuation of this response eventually leads to heart failure. The histone acetyltransferase p300 plays an important role in the development of heart failure, and may be a target for heart failure therapy. The phenolic phytochemical 6-shogaol, a pungent component of raw ginger, has various bioactive effects; however, its effect on cardiovascular diseases has not been investigated. One micromolar of 6-shogaol suppressed phenylephrine (PE)-induced increases in cardiomyocyte hypertrophy in rat primary cultured cardiomyocytes. In rat primary cultured cardiac fibroblasts, 6-shogaol suppressed transforming growth factor-beta (TGF-β)-induced increases in L-proline incorporation. It also blocked PE- and TGF-β-induced increases in histone H3K9 acetylation in the same cells and in vitro. An in vitro p300-HAT assay revealed that 6-shogaol suppressed histone acetylation. The mice underwent transverse aortic constriction (TAC) surgery, and were administered 0.2 or 1 mg/kg of 6-shogaol daily for 8 weeks. 6-shogaol prevented TAC-induced systolic dysfunction and cardiac hypertrophy in a dose-dependent manner. Furthermore, it also significantly inhibited TAC-induced increases in histone H3K9 acetylation. These results suggest that 6-shogaol may ameliorate heart failure through a variety of mechanisms, including the inhibition of p300-HAT activity.

Ginsenoside Rb1 promotes the activation of PPARα pathway via inhibiting FADD to ameliorate heart failure

PurposeGinsenoside Rb1 (GRb1), a dammarane-type triterpene saponin compound mainly distributed in ginseng (Panax ginseng), has been demonstrated to ameliorate cardiovascular diseases. However, it remains unclear whether GRb1 alleviates heart failure (HF) by maintaining cardiac energy metabolism balance. Therefore, this work aimed to investigate the cardiac benefits of GRb1 against cardiac energy deficit and explore its mechanism of action. Methods and resultsIsoproterenol (ISO) induced HF Sprague–Dawley rats were administrated with GRb1 or fenofibrate for 6 weeks. ISO-induced primary neonatal rat cardiomyocytes (NRCMs) were used as the in vitro model. In vivo, GRb1 significantly improved the structural and metabolic disorder, as demonstrated by the restoration of cardiac function, inhibition of cardiac hypertrophy and fibrosis, and increased adenosine triphosphate (ATP) generation. In vitro, GRb1 effectively protected mitochondrial function and scavenged excessive reactive oxygen species. Moreover, in ISO-induced NRCMs, GRb1 significantly inhibited the abnormal upregulation of Fas-associated death domain (FADD), promoted transcriptional activation of peroxisome proliferator-activated receptor-alpha (PPARα), improved the aberrant expression of cardiac energy metabolism-related enzymes and cardiac fatty acid oxidation, and subsequently increased the synthesis of ATP. Noticeably, GRb1 could inhibit the increased binding between FADD and PPARα, which contributed to the activation of PPARα. Furthermore, GRb1 strengthened the thermal stabilization of FADD and might bind to FADD directly. ConclusionsCollectively, it’s part of the in-depth mechanism of GRb1’s cardio-protection that GRb1 could directly bind to FADD and counteract its negative role in the transcription of PPARα thus ameliorating cardiac energy derangement and HF.

Combined analysis of plasma metabolome and intestinal microbiome sequencing to explore jiashen prescription and its potential role in changing intestine-heart axis and effect on chronic heart failure.

Heart failure (HF) is a syndrome with global clinical and socioeconomic burden worldwide owing to its poor prognosis. Jiashen Prescription (JSP), a traditional Chinese medicine (TCM) formula, exhibits unambiguous effects on treating HF. Previously, we have reported that underlying mechanisms of JSP by an untargeted metabolomics approach, but the contribution of gut microbiota and metabolic interaction to the cardioprotective efficacy of JSP remains to be elucidated. Firstly, the rat model of heart failure was established by the permanent ligation of the left anterior descending coronary artery. The efficacy evaluation of JSP in treating HF rats was per-formed by left ventricular ejection fraction (LVEF). Then, 16S rRNA gene sequencing and LC/MS-based metabolomic analysis were utilized to explore the characteristics of cecal-contents microecology and plasma metabolic profile, respectively. After that, the correlation between intestinal micro-ecological characteristics and plasma metabolic characteristics was analyzed to explore the potential mechanism of the JSP treatment in HF. JSP could improve the cardiac function of heart failure rats and thus ameliorate heart failure via enhancing rat LVEF. Results of intestinal flora analysis revealed that JSP not only adjusted gut microbiota disturbances by enriching species diversity, reducing the abundance of pathogenic bacteria (such as Allobaculum, Brevinema), as well as increasing the abundance of beneficial bacteria (such as Lactobacillus, Lachnospiraceae_NK4A136_group), but also improved metabolic disorders by reversing metabolite plasma levels to normality. Through the conjoint analysis of 8 metabolites and the OTUs relative abundance data in the 16srRNA sequencing results by WGCNA method, 215 floras significantly related to the eight compounds were identified. The results of the correlation analysis demonstrated a significant association between intestinal microbiota and plasma metabolic profile, especially the significant correlation of Ruminococcaceae_UCG-014 and Protoporphyrin IX, Ruminococcaceae_UCG-005, Christensenellaceae_R-7_group and nicotinamide, dihydrofolic acid. The present study illustrated the underlying mechanism of JSP to treat heart failure by affecting intestinal flora and plasma metabolites, provide a potential therapeutic strategy against heart failure.

Low-carbohydrate diets containing plant-derived fat but not animal-derived fat ameliorate heart failure

Cardiovascular disease (CVD) is a global health burden in the world. Although low-carbohydrate diets (LCDs) have beneficial effects on CVD risk, their preventive effects remain elusive. We investigated whether LCDs ameliorate heart failure (HF) using a murine model of pressure overload. LCD with plant-derived fat (LCD-P) ameliorated HF progression, whereas LCD with animal-derived fat (LCD-A) aggravated inflammation and cardiac dysfunction. In the hearts of LCD-P-fed mice but not LCD-A, fatty acid oxidation-related genes were highly expressed, and peroxisome proliferator-activated receptor α (PPARα), which regulates lipid metabolism and inflammation, was activated. Loss- and gain-of-function experiments indicated the critical roles of PPARα in preventing HF progression. Stearic acid, which was more abundant in the serum and heart of LCD-P-fed mice, activated PPARα in cultured cardiomyocytes. We highlight the importance of fat sources substituted for reduced carbohydrates in LCDs and suggest that the LCD-P-stearic acid-PPARα pathway as a therapeutic target for HF.

Empagliflozin suppressed cardiac fibrogenesis through sodium-hydrogen exchanger inhibition and modulation of the calcium homeostasis

BackgroundThe novel sodium-glucose co-transporter 2 inhibitor (SGLT2i) potentially ameliorates heart failure and reduces cardiac arrhythmia. Cardiac fibrosis plays a pivotal role in the pathophysiology of HF and atrial myopathy, but the effect of SGLT2i on fibrogenesis remains to be elucidated. This study investigated whether SGLT2i directly modulates fibroblast activities and its underlying mechanisms.Methods and resultsMigration, proliferation analyses, intracellular pH assay, intracellular inositol triphosphate (IP3) assay, Ca2+ fluorescence imaging, and Western blotting were applied to human atrial fibroblasts. Empagliflozin (an SGLT2i, 1, or 5 μmol/L) reduced migration capability and collagen type I, and III production. Compared with control cells, empagliflozin (1 μmol/L)- treated atrial fibroblasts exhibited lower endoplasmic reticulum (ER) Ca2+ leakage, Ca2+ entry, inositol trisphosphate (IP3), lower expression of phosphorylated phospholipase C (PLC), and lower intracellular pH. In the presence of cariporide (an Na+-H+ exchanger (NHE) inhibitor, 10 μmol/L), control and empagliflozin (1 μmol/L)-treated atrial fibroblasts revealed similar intracellular pH, ER Ca2+ leakage, Ca2+ entry, phosphorylated PLC, pro-collagen type I, type III protein expression, and migration capability. Moreover, empagliflozin (10 mg/kg/day orally for 28 consecutive days) significantly increased left ventricle systolic function, ß-hydroxybutyrate and decreased atrial fibrosis, in isoproterenol (100 mg/kg, subcutaneous injection)-induced HF rats.ConclusionsBy inhibiting NHE, empagliflozin decreases the expression of phosphorylated PLC and IP3 production, thereby reducing ER Ca2+ release, extracellular Ca2+ entry and the profibrotic activities of atrial fibroblasts.

Plasma metabolomic analysis reveals the therapeutic effects of Jiashen tablets on heart failure.

Heart failure is a chronic progressive condition that significantly affects the quality of life of patients with high hospitalization and mortality rates. Jiashen tablets (JST), a Chinese herbal formula, have been reported to be an effective treatment against heart failure, however the underlying mechanisms remain obscure. This study was designed to determine the effect of JST on the treatment of heart failure and delineate the underlying mechanisms by an untargeted metabolomics approach. The chronic heart failure model was established by the permanent ligation of the left anterior descending coronary artery in rats. The cardiac functions of rats, including left ventricular ejection fraction (LVEF) and fractional shortening (LVFS), left ventricular internal diameter end diastole (LVIDd) and end systole (LVIDs), and interventricular septum thickness in diastole (IVSd) and in systole (IVSs), were measured by echocardiography. Biochemical analysis and histopathological examination were also performed to evaluate therapeutic effects of JST for treating heart failure. UHPLC-QTOF-MS/MS coupled with multivariate statistical analyses were applied for plasma metabolic profiling to identify biomarkers and potential mechanisms of JST in the treatment of heart failure. Jiashen tablets could improve the cardiac function of heart failure rats and thus ameliorate heart failure via enhancing rat LVEF and LVFS and decreasing LVIDd, LVIDs, IVSd, and IVSs. Results of biochemical analysis and histopathological examination revealed that JST could reduce the serum lactate dehydrogenase (LDH) activity and the level of NT-pro BNP, markers of heart failure and myocardial damage, and inhibit myocardial fibrosis. Furthermore, in metabolomics analysis, a total of 210 metabolites with significant differences were identified between heart failure rats and normal rats, among which 29 metabolites were significantly restored after JST treatment. These metabolites were primarily involved in tryptophan metabolism, branched-chain amino acid metabolism, fatty acids β-oxidation, and glycerophospholipid metabolism. The present study illustrated the therapeutic effect of JST for the treatment of heart failure and delineated the underlying mechanisms mainly relating to the regulation of amino acid metabolism and lipid metabolism in heart failure rats.

Canagliflozin mitigates ferroptosis and ameliorates heart failure in rats with preserved ejection fraction

Recently, hypoglycemic drugs belonging to sodium-glucose cotransporter 2 inhibitors (SGLT2i) have generated significant interest due to their clear cardiovascular benefits for heart failure with preserved ejection fraction (HFpEF) since there are no effective drugs that may improve clinical outcomes for these patients over a prolonged period. But, the underlying mechanisms remain unclear, particularly its effects on ferroptosis, a newly defined mechanism of iron-dependent non-apoptotic cell death during heart failure (HF). Here, with proteomics, we demonstrated that ferroptosis might be a key mechanism in a rat model of high-salt diet-induced HFpEF, characterized by iron overloading and lipid peroxidation, which was blocked following treatment with canagliflozin. Data are available via ProteomeXchange with identifier PXD029031. The ferroptosis was evaluated with the levels of acyl-CoA synthetase long-chain family member 4, glutathione peroxidase 4, ferritin heavy chain 1, transferrin receptor, Ferroportin 1, iron, glutathione, malondialdehyde, and 4-hydroxy-trans-2-nonenal. These findings highlight the fact that targeting ferroptosis may serve as a cardioprotective strategy for HFpEF prevention and suggest that canagliflozin may exert its cardiovascular benefits partly via its mitigation of ferroptosis.

Exploration of Mechanisms of Sacubitril/Valsartan in the Treatment of Cardiac Arrhythmias Using a Network Pharmacology Approach.

Significant reductions in the incidence of cardiac arrhythmia (CA) and sudden cardiac death (SCD), along with amelioration of heart failure, have been reported for treatment with Sacubitril/valsartan (SV). However, its anti-arrhythmic mechanism remains unclear. The current study aims to explore the anti-arrhythmic molecular mechanism of SV. The direct protein targets (DPT) of SV were extracted from DrugBank. The protein-protein interaction (PPI) network of SV DPTs was constructed using STRING, and the indirect protein targets (IPTs) were also identified. A search for arrhythmia-related genes was conducted using GeneCards and the Comparative Toxicogenomics Database (CTD). The DTPs, ITPs, and arrhythmia-related genes from the two datasets were combined in a Venn diagram, and the overlapping genes were identified as core target genes. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses identified the top 20 biological processes and signaling pathways related to disease and the therapeutic effects of SV. The renin-angiotensin system, adrenergic signaling in cardiomyocytes, and gap junction pathways are strongly implicated in the effects of SV on CA. In conclusion, our bioinformatics analyses provided evidence pertaining to the possible antiarrhythmic mechanisms of SV and may contribute to the development of novel drugs for CA.

Citri Reticulatae Pericarpium alleviates postmyocardial infarction heart failure by upregulating PPARγ expression.

Heart failure after myocardial infarction (MI) is the leading cause of death worldwide. Citri Reticulatae Pericarpium (CRP) is a traditional Chinese herbal medicine that has been used in the clinic for centuries. In this study, we aimed to investigate the roles of CRP in cardiac remodelling and heart failure after MI, as well as the molecular mechanisms involved. Male C57BL/6 mice aged 8 weeks were subjected to coronary artery ligation to mimic the clinical situation in vivo. Echocardiography was used to assess the systolic function of the mouse heart. Masson trichrome staining and Wheat germ agglutinin (WGA) staining were utilised to determine the fibrotic area and cross-sectional area of the mouse heart, respectively. Cardiomyocytes and fibroblasts were isolated from neonatal rats aged 0-3 days in vitro using enzyme digestion. TUNEL staining and EdU staining were performed to evaluate apoptosis and proliferation, respectively. Gene expression changes were analysed by qRT-PCR, and protein expression changes were assessed by Western blotting. Our findings revealed that CRP attenuated cardiac hypertrophy, fibrosis and apoptosis and alleviated heart failure after MI in vivo. Furthermore, CRP mitigated cardiomyocyte apoptosis and fibroblast proliferation and differentiation into myofibroblasts. In addition, the PPARγ inhibitor T0070907 completely abolished the abovementioned beneficial effects of CRP, and the PPARγ activator rosiglitazone failed to further ameliorate cardiac apoptosis and fibrosis in vitro. CRP alleviates cardiac hypertrophy, fibrosis, and apoptosis and can ameliorate heart failure after MI via activation of PPARγ.