Model Of Chronic Heart Failure Research Articles

Calcium ATPase (PMCA) and GLUT-4 Upregulation in the Transverse Tubule Membrane of Skeletal Muscle from a Rat Model of Chronic Heart Failure.

Intolerance to exercise is a symptom associated with chronic heart failure (CHF) resulting in SM waste and weakness in humans. The effect of CHF on skeletal muscle (SM) arose from experimental evidence in rat models to explain the underlying mechanism. We investigated SM mechanical and metabolic properties in sham rats and with coronary ligation-induced CHF. After twelve weeks of CHF, rats were catheterized to measure right auricular pressure, SM mechanical properties, SERCA-ATPase activity and plasma membrane Ca2+-ATPase (PMCA) hydrolytic activity in isolated sarcoplasmic reticulum (SR) and transverse tubule (TT membrane), respectively, in the sham and CHF. The right auricular pressure and plasma nitrite concentration in CHF increased two-fold with respect to the sham. Pleural effusion and ascites were detected in CHF, confirming CHF. SERCA activity was conserved in CHF. In TT membranes from CHF, the glucose transporter GLUT4 increased seven-fold, and the PMCA hydrolytic activity increased five-fold, but in isolated muscle, the mechanical properties were unaffected. The absence of a deleterious effect of coronary ligation-induced CHF in the rat model on SM could be explained by the increased activity of PMCA and increased presence of GLUT-4 on the TT membrane, which may be involved in the mechanical outcome of the EDL.

Ex vivo modelling of cardiac injury identifies ferroptosis-related pathways as a potential therapeutic avenue for translational medicine

BackgroundHeart failure (HF) is a burgeoning health problem worldwide. Often arising as a result of cardiac injury, HF has become a major cause of mortality with limited availability of effective treatments. Ferroptotic pathways, triggering an iron-dependent form of cell death, are known to be potential key players in heart disease. This form of cell death does not exhibit typical characteristics of programmed cell death, and is mediated by impaired iron metabolism and lipid peroxidation signalling. ObjectivesThe aim of this study is to establish an ex-vivo model of myocardial injury in living myocardial slices (LMS) and to identify novel underlying mechanisms and potential therapeutic druggable target(s). Methods and resultsIn this study, we employed LMS as an ex vivo model of cardiac injury to investigate underlying mechanisms and potential therapeutic targets. Cryoinjury was induced in adult rat LMS, resulting in 30 % tissue damage. Cryoinjured LMS demonstrated impaired contractile function, cardiomyocyte hypertrophy, inflammation, and cardiac fibrosis, closely resembling in vivo cardiac injury characteristics. Proteomic analysis revealed an enrichment of factors associated with ferroptosis in the injured LMS, suggesting a potential causative role. To test this hypothesis, we pharmacologically inhibited ferroptotic pathways using ferrostatin (Fer-1) in the cryoinjured rat LMS, resulting in attenuation of structural changes and repression of pro-fibrotic processes. Furthermore, LMS generated from failing human hearts were used as a model of chronic heart failure. In this model, Fer-1 treatment was observed to reduce the expression of ferroptotic genes, enhances contractile function and improves tissue viability. Blocking ferroptosis-associated pathways in human cardiac fibroblasts (HCFs) resulted in a downregulation of fibroblast activation genes, a decrease in fibroblast migration capacity, and a reduction in reactive oxygen species production. RNA sequencing analysis of Fer-1-treated human LMS implicated metallothioneins as a potential underlying mechanism for the inhibition of these pathways. This effect is possibly mediated through the replenishment of glutathione reserves. ConclusionsOur findings highlight the potential of targeting ferroptosis-related pathways and metallothioneins as a promising strategy for the treatment of heart disease.

Integrating bioinformatics and ferroptosis to reveal the protective mechanism of Astragaloside IV on chronic heart failure rats

Ferroptosis is an important pathological mechanism of chronic heart failure (CHF). This study aimed to investigate the protective mechanism of Astragaloside IV (AS-IV) on CHF rats by integrating bioinformatics and ferroptosis. CHF-related targets and ferroptosis-related targets were collected. After the intersection, the common targets were obtained. The PPI network of the common targets was constructed, and topological analysis of the network was carried out. The target with the highest topological parameter values was selected as the key target. The key target p53 was obtained through bioinformatics analysis, and its molecular docking model with AS-IV was obtained, as well as molecular dynamics simulation analysis. The rat models of CHF after myocardial infarction were established by ligation of left coronary artery and treated with AS-IV for 4 weeks. AS-IV treatment significantly improved cardiac function in CHF rats, improved cardiomyocyte morphology and myocardial fibrosis, reduced mitochondrial damage, decreased myocardial MDA and Fe2+ content, increased GSH content, inhibited the expression of p53 and p-p53, and up-regulated the expression of SLC7A11 and GPX4. In conclusion, AS-IV improved cardiac function in CHF rats, presumably by regulating p53/SLC7A11/GPX4 signaling pathway and inhibiting myocardial ferroptosis.

In Vivo Testing of a Second-Generation Prototype Accessory for Single Transapical Left Ventricular Assist Device Implantation.

A new accessory was developed to allow implantation of left ventricular assist devices (LVADs) without requiring an anastomosis to the ascending aorta. The accessory combines the LVAD inflow and outflow into a dual-lumen device. Initial prototypes encountered reduced pump performance in vitro, but a second-generation prototype successfully addressed this issue. This feasibility study aimed to demonstrate the anatomic fit, safe implantation, and hemodynamic effectiveness of the LVAD with the accessory. The accessory was implanted in ten female pigs (104 ± 13 kg). Following sternotomy and apical coring under cardiopulmonary bypass, a balloon catheter was retrogradely inserted and exteriorized through the coring site, where it was inflated within the distal third of the outflow graft. It was utilized to pull the accessory's outflow across the aortic valve. After LVAD attachment, the catheter was removed. Echocardiography revealed no relevant valve regurgitation post-implantation. During ramp testing, pump flow increased from 3.7 ± 1.2 to 5.4 ± 1.2 L/min. Necropsy confirmed correct accessory placement in nine animals. No valve lesions or device thrombosis were observed. The accessory enabled LVAD implantation without compromising pump performance. Future work includes design refinements for implantation without cardiopulmonary bypass and long-term testing in a chronic heart failure model.

Abstract We072: Effects of electronic cigarettes on mouse cardiac lymphatic vessels after TAC surgery

Introduction: Heart failure is a public health concern worldwide. It is known that tobacco smoking is a risk factor of heart failure. Tobacco smoking also causes inflammation reaction and lymphatic dysfunction in the lung. However, the effects of electronic cigarettes (ECIG), as a new method of smoking, on the heart and cardiac lymphatic vessels (lymphatics) are not clear yet. The lymphatic vessels play an important role in maintaining cardiac function by modulating fluid homeostasis and transporting macromolecules. It has been reported that cardiac lymphatic vessel formation limits pressure overload-induced heart failure in C57Bl/6 but not in Balb/c mice. How cardiac lymphatics might contribute to the pathogenesis induced by ECIG is not known. Research Questions: The roles of cardiac lymphatic vessels in responses to ECIG exposure are not investigated. I hypothesize that the toxic effects of ECIG on the heart are partially caused by damaging the cardiac lymphatic vessels. Aim: To determine the effects of ECIG exposure on cardiac lymphatics after Transverse aortic constriction (TAC). Methods: I perform TAC surgery on mice as a heart hypertrophy and chronic heart failure model. Mice after TAC or Sham surgery are treated with different vaping components from ECIG: ECIG, propylene glycol and glycerin (PGVG) as vehicle, and air. After 4 weeks of treatment, hearts were harvested for histological analyses. The lymphatic vessel coverage percentage and morphology were examined by immunostaining. Results: Prior research suggested that genetic background in mice might affect the responses of cardiac lymphatic vessels to TAC-induced heart failure. I have established the TAC model using CD-1 mice. My results showed that CD-1 mice treated with PGVG after TAC do not show a significant difference in cardiac lymphatic vessel density compared to Sham group (p value=0.5951). ECIG treatment also did not affect the lymphatic density significantly compared to PGVG treated mice after sham operation (p value=0.8937). ECIG treated mice after TAC surgery showed a trend of increased lymphatic coverage and more mice are still being processed and will be presented at the conference. Conclusion: PGVG treated CD-1 mice do not show changes in lymphatic vessel density 4 weeks post TAC. Longer time points and more mouse numbers are needed to compare the effects of PGVG and ECIG after TAC induced hypertrophy and heart failure. This research is supported by California TRDRP grant.

Achieving consensus on the key elements of a nurse-led multidisciplinary chronic heart failure service in Thailand: An e-Delphi study.

To describe the outcomes of an e(electronic)-Delphi survey used to achieve consensus on the essential elements that should be included in a multidisciplinary, nurse-led service for patients with chronic heart failure (CHF). The study design was based on a three-round e-Delphi survey. A series of three survey rounds were used to gather expert opinions and achieve consensus on the key elements that should be included in a CHF disease management program from a sample of healthcare professionals and organizational leaders with expertise in existing CHF services. Consensus for each item was defined as at least 90% agreement. There were 20 participants (18 healthcare professionals and 2 organizational leaders) in round-1, 22 (20 healthcare professionals and 2 organizational leaders) in round-2, and 17 (15 healthcare professionals and 2 organizational leaders) in round-3. Fifteen participants attended a final online meeting (13 healthcare professionals and 2 organizational leaders). Consensus was obtained on five essential components: (i) consumer education, (ii) treatment optimization using a multidisciplinary approach, (iii) discharge planning, (iv) provision of supportive community care and (v) mechanisms to respond to early symptoms of decompensated CHF. Participants focused on mechanisms to improve treatment effectiveness, patient and family knowledge, communication between healthcare providers and supportive care in the community. The proposed model of care may be useful to other health service providers who are designing or adapting CHF models of care for the South-East Asian environment. This research provides a solid basis for using a Delphi method to resolve the challenges and issues of transferring global model-based recommendations in CHF knowledge. The Delphi method proved successful as an important step in developing a culturally acceptable model of chronic care that meets the goals of local healthcare providers.

Disorder of neuroplasticity aggravates cognitive impairment via neuroinflammation associated with intestinal flora dysbiosis in chronic heart failure.

Chronic heart failure (CHF) impairs cognitive function, yet its effects on brain structure and underlying mechanisms remain elusive. This study aims to explore the mechanisms behind cognitive impairment. CHF models in rats were induced by ligation of the left anterior descending coronary artery. Cardiac function was analyzed by cardiac ultrasound and hemodynamics. ELISA, immunofluorescence, Western blot, Golgi staining and transmission electron microscopy were performed on hippocampal tissues. The alterations of intestinal flora under the morbid state were investigated via 16S rRNA sequencing. The connection between neuroinflammation and synapses is confirmed by a co-culture system of BV2 microglia and HT22 cells in vitro. Results: CHF rats exhibited deteriorated cognitive behaviors. CHF induced neuronal structural disruption, loss of Nissl bodies, and synaptic damage, exhibiting alterations in multiple parameters. CHF rats showed increased hippocampal levels of inflammatory cytokines and activated microglia and astrocytes. Furthermore, the study highlights dysregulated PDE4-dependent cAMP signaling and intestinal flora dysbiosis, closely associated with neuroinflammation, and altered synaptic proteins. In vitro, microglial neuroinflammation impaired synaptic plasticity via PDE4-dependent cAMP signaling. Neuroinflammation worsens CHF-related cognitive impairment through neuroplasticity disorder, tied to intestinal flora dysbiosis. PDE4 emerges as a potential therapeutic target. These findings provide insightful perspectives on the heart-gut-brain axis.

Shenfu Injection regulates macrophage polarization via TLR4/NF-κB pathway to reduce inflammation in chronic heart failure

This study aimed to investigate the therapeutic effect of Shenfu Injection on mice with chronic heart failure(CHF) and its effect on macrophage polarization. C57BL/6J mice were randomly assigned to the normal and model groups. The CHF model was established by intraperitoneal injection of isoproterenol(ISO, 7.5 mg·kg~(-1), 28 d). The successful modeling was determined by asses-sing the cardiac function and N-terminal pro-brain natriuretic peptide(NT-proBNP). The modeled mice were randomly divided into the model group, Shenfu Injection group, and TAK-242 group, and were injected intraperitoneally with the corresponding drugs for 15 days. Cardiac function was evaluated using echocardiography. Hematoxylin-eosin(HE) staining was used to detect the pathomorphology. Enzyme-linked immunosorbent assay(ELISA) was used to detect the values of serum NT-proBNP, interleukin-6(IL-6), tumor necrosis factor-α(TNF-α), IL-10, and arginase 1(Arg-1). Flow cytometry was applied to detect the relative content and M1/M2 polarization of cardiac macrophages. Quantitative polymerase chain reaction(qPCR) and Western blot were used to detect the changes in the Toll-like receptor 4(TLR4)/nuclear factor-κB(NF-κB) pathway-related mRNA and protein expressions. Compared with the normal group, mice in the model group had lower values of left ventricular ejection fraction(LVEF) and left ventricular fractional shorte-ning(LVFS), higher values of left ventricular internal diastolic end-diastolic(LVIDd), left ventricular internal diastolic end-systolic(LVIDs), NT-proBNP, TNF-α, and IL-6(P<0.01); the number of macrophages increased in cardiac tissues(P<0.05), and the values of M1-F4/80~+CD86~+ were increased(P<0.01), while the values of M2-F4/80~+CD163~+ decreased(P<0.05); the mRNA and protein expressions of TLR4, myeloid differentiation factor 88(MyD88), IκB kinase α(IKKα), and NF-κB p65 in myocardial tissues were significantly elevated(P<0.05, P<0.01). Compared with the model group, mice in the Shenfu Injection and TAK-242 groups showed elevated LVEF, LVFS, IL-10, and Arg-1 levels, and decreased LVIDd, LVIDs, NT-proBNP, TNF-α, and IL-6 levels(P<0.05, P<0.01); the cardiac F4/80~+CD11b~+(macrophage) and M1-F4/80~+ CD86~+ values were significantly down-regulated, while M2-F4/80~+CD163~+ values were increased(P<0.05, P<0.01); and the mRNA and protein expressions of TLR4, MyD88, IKKα, and NF-κB p65 in myocardial tissues were notably decreased(P<0.05, P<0.01). CHF mice have an imbalance of M1/M2 macrophage polarization, with M1-type macrophages predominating. Shenfu Injection promotes macrophage polarization towards M2, inhibits M1-type macrophage activation, and attenuates inflammatory responses in heart failure by regulating the TLR4/NF-κB signaling pathway.

Xinbao pill attenuated water retention by regulating the CaSR/AQP2 pathway in LAD-induced chronic heart failure rats

BackgroundWater retention is one of the important factors in the development and exacerbation of chronic heart failure (CHF). Xinbao Pill (XBP) is widely used as an adjuvant therapy for CHF. However, the therapeutic effect of XBP on water retention in CHF remains unclear. PurposeOur research was aimed to investigate the effect and mechanism of XBP on water retention in CHF. MethodsMale Sprague-Dawley (SD) rats underwent left anterior descending (LAD) artery ligation to establish the CHF model and were subsequently administrated with different doses of XBP or Qili Qiangxin (QLQX). Cardiac functions were assessed using M-mode echocardiography. Cardiac remodeling and myocardial fibrosis were observed using HE and Masson staining. Additionally, the expression of the CaSR/AQP2 signaling pathway in the renal was detected using western blotting analysis, quantitative PCR analysis, immunofluorescence staining, immunohistochemistry, and co-immunoprecipitation assays. Furthermore, CaSR inhibitor NPS2143 was used to confirm the role of CaSR on the effect of XBP for water retention. ResultsIn the LAD-induced CHF rat model, XBP improved EF (ejection fraction) and LVFS (fractional shortening), and alleviated cardiac fibrosis. Importantly, XBP significantly increased the 24-h urine volume and decreased urinary protein level after CHF. Further mechanism studies showed that XBP treatment could decrease the expression of renal AQP2 at the protein and mRNA levels. Moreover, XBP promoted renal AQP2 ubiquitination by upregulating CaSR and p-p38-MAPK expression. Meanwhile, XBP suppressed the expression of p-CREB to inhibit the mRNA expression of AQP2 in the renal tissue. However, NPS2143 blocked the beneficial effects of XBP on cardiac function and water retention, even stopped the inhibitory effect on AQP2 expression by XBP. ConclusionOur study revealed that XBP improved water retention against CHF via promoting CaSR/p38-MAPK-mediated AQP2 ubiquitination and regulating CaSR/CREB-mediated AQP2 transcription.

Effect of moxibustion at "Xinshu" (BL15) and "Feishu" (BL13) on expression of TRPV1 and CGRP in the myocardial tissue of chronic heart failure rats.

To observe the effect of moxibustion at "Xinshu" (BL15) and "Feishu" (BL13) on transient receptor potential vanilloid type 1(TRPV1), calcitonin gene-related peptide (CGRP), and serum interleukin-10 (IL-10) in the myocardial tissue of rats with chronic heart failure (CHF), so as to explore its underlying mechanisms in improvement of CHF. Male SD rats were randomly divided into the normal, model, moxibustion, capsaicin, moxibustion + capsaicin, and moxibustion + solvent groups, with 10 rats in each group. The CHF model was established by permanent ligation of the anterior descending branch of the left coronary artery. Mild moxibustion was applied to bilateral BL13 and BL15 for 30 min once daily for 4 weeks. Rats in the capsaicin group were smeared with capsaicin in the acupoint area once a day for 4 weeks. For rats of the moxibustion + capsaicin and moxibustion + solvent groups, capsaicin and solvent were applied to the acupoint area before moxibustion for 4 weeks, respectively. The ejection fraction (EF) and left ventricular fractional shortening rate (FS) were examined by echocardiography. HE staining was used to observe the myecardial morphological structure. The mRNA and protein expression levels of TRPV1, CGRP and galectin-3 (Gal-3) in myocardial tissue were detected by real-time quantitative PCR and Western blot, respectively. The content of IL-10 in serum was detected by ELISA. After modeling, the pathological changes of myocardium (as cardiac muscle fiber disorder, inflammatory cell infiltration, etc.) were obvious, and the EF, FS, serum IL-10, protein and mRNA exspression of TRPV1 and CGRP were significantly decreased (P<0.01) in the model group compared with the normal group, while the protein and mRNA exspression of Gal-3 were significantly up-regulated (P<0.01). Following the interventions, the above-mentioned indexes were all reversed in moxibustion, capsaicin, and moxibustion + capsaicin groups (P<0.01), and the effect of moxibustion + capsaicin was the best (P<0.05, P<0.01). Moxibustion can reduce myocardial injury and improve cardiac function in CHF rats, which may be related to its effects in up-regulating the expression of TRPV1 and CGRP, and down-regulating the expression of Gal-3 to alleviate myocardial fibrosis.

Sacubitril/valsartan ameliorates cardiac function and ventricular remodeling in CHF rats via the inhibition of the tryptophan/kynurenine metabolism and inflammation

Sacubitril/valsartan has been highly recognized as a treatment for Chronic heart failure (CHF). Its potential cardioprotective benefits and mechanisms, however, remain to be explored. Metabolomics can be used to identify the metabolic characteristics and related markers, as well as the influence of drugs, thereby opening up the new mechanism for sacubitril/valsartan therapy in CHF disease. In this study, the ligation of left anterior descending and exhaustive swimming were used to induce a rat model of CHF after myocardial infarction. The efficacy was appraised with echocardiography, serum NT-proBNP, and histopathologica. UPLC-Q/TOF–MS combined with multivariate statistical analysis approach were used to analyze the effect of sacubitril/valsartan on CHF rats. RT-qPCR and western blot were performed to investigate the tryptophan/kynurenine metabolism pathway. Accordingly, the basal cardiac function were increased, while the serum NT-proBNP and collagen volume fraction decreased in CHF rats with sacubitril/valsartan. Sacubitril/valsartan regulated the expression of kynurenine et.al 8 metabolomic biomarkers in CHF rats serum, and it contributed to the cardioprotective effects through tryptophan metabolism pathway. In addition, the mRNA and protein expression of the indoleamine 2,3-dioxygenase (IDO) in the myocardial tissue of CHF rats, were down-regulated by sacubitril/valsartan, which was the same with the IL-1β, IFN-γ, TNF-α, COX-2, and IL-6 mRNA expression, and IL-1β, IFN-γ, and TNF-α expression in serum. In conclusion, sacubitril/valsartan can ameliorate cardiac function and ventricular remodeling in CHF rats, at least in part through inhibition of tryptophan/kynurenine metabolism.

Exploring the Efficacy Enhancement Mechanism of Qixue Shuangbu prescription after TCM processing for treating chronic heart failure by regulating ERK/Bcl-2/Bax/Caspases-3 signaling pathway

Qixue Shuangbu prescription (QSP) has been used for the treatment of chronic heart failure (CHF) with remarkable curative effect. Processed QSP (PQSP) could significantly improve the treatment of CHF after traditional Chinese medicine (TCM) processing. This study elucidated the underlying efficacy enhancement mechanism of QSP after TCM processing for treating CHF in vitro and in vivo. The injury of rat cardiomyoblast H9c2 cells was induced by anoxia/reoxygenation to mimic CHF state in vitro. Sixty Sprague-Dawley rats were used to established CHF model by intraperitoneally injecting doxorubicin (the accumulative dose 15 mg/kg). Biochemical examinations were performed in serum and cellular supernatant, respectively. Cardiac functions and histopathological changes were evaluated in CHF model rats. The protein and mRNA levels of ERK1/2, Bcl-2, Bax and Caspase-3 were evaluated by Western blot and RT-PCR, respectively. All above results of low dose crude QSP-treated group (L-CQSP), high dose CQSP-treated group (H-CQSP), low dose PQSP-treated group (L-PQSP), high dose PQSP-treated group (H-PQSP) were compared to systematically explore correlations between TCM processing and the efficacy enhancement for treating CHF of PQSP. Compared with the model group, the L-CQSP group showed significant improvement in cardiac function at 8th weeks, while no significant improvement in cardiomyocyte apoptosis and fibrosis. Both H-CQSP, L-PQSP and H-PQSP exerted beneficial therapeutic effects in injured H9c2 cardiomyocytes and CHF model rats. L-PQSP and H-PQSP significantly increased cell viability and the activity of SOD, decreased the activities of LDH, MDA and NO, up-regulated the expression of ERK1/2 and Bcl-2, down-regulated the expression of Bax and Caspase-3 compared to the same dosage of CQSP. The efficacy enhancement mechanism of PQSP after TCM processing for treating CHF was directly related to the regulation of ERK/Bcl-2/Bax/Caspases-3 signaling pathway.

Preventive and Therapeutic Effects of Crocetin in Rats with Heart Failure.

Gardenia is both a food and medicine plant. It is widely used for cardiovascular protection, and its main bioactive ingredient is crocetin. This study aims to observe the therapeutic effects of crocetin on chronic heart failure in rats induced by various etiologies. It further compares the efficacy differences between preventative and treatment administration, varying dosages, and treatment durations, to provide improved guidance for medication in heart failure rats and determine which categories of chronic heart failure rats might benefit most from crocetin. Chronic heart failure models induced by abdominal aorta constriction, renal hypertension, and coronary artery ligation were constructed. By examining cardiac function, blood biochemistry, and histopathology, the study assessed the preventive and therapeutic effects of crocetin on load-induced and myocardial ischemia-induced heart failure. The results showed that in all three models, both treatment and preventative administration of crocetin significantly improved chronic heart failure in rats, especially in preventative administration. The results indicate crocetin may be beneficial for improving symptoms and functional capacity in rats with heart failure. Furthermore, long-term administration was more effective than short-term administration across all three rat models, with therapeutic onset observed over 6 weeks.

Effect of moxibustion combined with intraperitoneal injection of benazepril on endoplasmic reticulum stress-related protein phosphorylation in rats with chronic heart failure.

To observe the effect of moxibustion at "Xinshu"(BL15) and "Feishu"(BL13) combined with intraperitoneal injection of benazepril on cardiac function and phosphorylation of protein kinase R-like endoplasmic reticulum kinase (PERK) and eukaryotic initiation factor 2α (elF2α) proteins in myocardium of rats with chronic heart failure (CHF), so as to explore its potential mechanism underlying improvement of CHF. A total of 42 male SD rats were randomly assigned to blank control (n=10), CHF model (n=7), medication (benazepril, n=8), moxibustion (n=8) and moxibustion+benazepril (n=9) groups, after cardiac ultrasound model identification and elimination of the dead. The CHF model was established by intraperitoneal injection of doxorubicin hydrochloride (DOX), once every week for 6 weeks. Mild moxibustion was applied to bilateral BL15 and BL13 regions for 20 min, once daily for 3 weeks. The rats of the medication group and moxibustion+benazepril group (benazepril was given first, followed by moxibustion) received intraperitoneal injection of benazepril (0.86 mg/kg) solution once daily for 3 weeks . The cardiac ejection fraction (EF) and left ventricular fractional shortening (FS) were measured using echocardiography. Histopathological changes of the cardiac muscle tissue were observed under light microscope after hematoxylin-eosin (H.E.) staining. Serum contents of B-type brain natriuretic peptide (BNP) and angiotensin Ⅱ (AngⅡ) were measured by enzyme-linked immunosorbent assay (ELISA). The expressions of phospho-PERK (p-PERK) and phospho-elF2α (p-elF2α) in the myocardium were detected by Western blot. Compared with the blank control group, the EF and FS of the left cardiac ventricle were significantly decreased (P<0.01), while the contents of serum BNP and AngⅡ, and expression levels of p-PERK and p-eIF2α significantly increased in the model group (P<0.01). In comparison with the model group, both the decreased EF and FS and the increased BNP and AngⅡ contents as well as p-PERK and p-elF2α expression levels were reversed by moxibustion, medication and moxibustion+benazepril (P<0.01). The effects of moxibustion+benazepril were markedly superior to those of simple moxibustion and simple medication in raising the levels of EF and FS rate and in down-regulating the contents of BNP, Ang Ⅱ, levels of p-PERK and p-elF2α (P<0.01, P<0.05). Outcomes of H.E. staining showed irregular arrangement of cardiomyocytes, cell swelling, vacuole and inflammatory infiltration in the model group, which was relatively milder in the 3 treatment groups. The effects of moxibustion+benazepril were superior to those of moxibustion or benazepril. Moxibustion combined with Benazepril can improve the cardiac function in CHF rats, which may be related to its functions in down-regulating the expression levels of myocardial p-PERK and p-elF2α to inhibit endoplasmic reticulum stress response.

Neutrophils are indispensable for adverse cardiac remodeling in heart failure

Persistent immune activation contributes significantly to left ventricular (LV) dysfunction and adverse remodeling in heart failure (HF). In contrast to their well-known essential role in acute myocardial infarction (MI) as first responders that clear dead cells and facilitate subsequent reparative macrophage polarization, the role of neutrophils in the pathobiology of chronic ischemic HF is poorly defined. To determine the importance of neutrophils in the progression of ischemic cardiomyopathy, we measured their production, levels, and activation in a mouse model of chronic HF 8 weeks after permanent coronary artery ligation and large MI. In HF mice, neutrophils were more abundant both locally in failing myocardium (more in the border zone) and systemically in the blood, spleen, and bone marrow, together with increased BM granulopoiesis. There were heightened stimuli for neutrophil recruitment and trafficking in HF, with increased myocardial expression of the neutrophil chemoattract chemokines CXCL1 and CXCL5, and increased neutrophil chemotactic factors in the circulation. HF neutrophil NETotic activity was increased in vitro with coordinate increases in circulating neutrophil extracellular traps (NETs) in vivo. Neutrophil depletion with either antibody-based or genetic approaches abrogated the progression of LV remodeling and fibrosis at both intermediate and late stages of HF. Moreover, analogous to murine HF, the plasma milieu in human acute decompensated HF strongly promoted neutrophil trafficking. Collectively, these results support a key tissue-injurious role for neutrophils and their associated cytotoxic products in ischemic cardiomyopathy and suggest that neutrophils are potential targets for therapeutic immunomodulation in this disease.

Canagliflozin combined with aerobic exercise protects against chronic heart failure in rats

To determine the efficacy and potential protective mechanism of canagliflozin combined with aerobic exercise in treating chronic heart failure (CHF). Isoproterenol was injected into rats to create CHF models. The rats were then subsequently divided into saline, canagliflozin (3mg/kg/d), aerobic exercise training, and canagliflozin combined with aerobic exercise training. Compared to the CHF group, the canagliflozin combined with the aerobic exercise group had superior ventricular remodeling and cardiac function. In rats treated with canagliflozin combined with aerobic exercise, the expression of cytochrome P450 (CYP) 4A3, CYP4A8, COL1A1, COL3A1, and FN1 was reduced, while the expression of CYP26B1, ALDH1A2, and CYP1A1 increased significantly. Additionally, canagliflozin combined with aerobic exercise decreased the phosphorylation of AKT and ERK1/2. Canagliflozin combined with aerobic exercise has a positive effect on the development of CHF via the regulation of retinol metabolism and the AKT/ERK signaling pathway.

Correlation of the Left Ventricular Systolic Dysfunction and Ventricular Depolarization in a Post-Infarction Model of Chronic Heart Failure.

The body surface potential mapping of the heart during the period of ventricular depolarization and the inotropic function of the ventricles were studied in rats under conditions of a translational model of post-infarction chronic heart failure developed by us. We revealed a statistically significant (p<0.001) correlation between the left-ventricular ejection fraction and the values of the maximum positive and negative extrema of the cardioelectric field on the body surface of rats with post-infarction chronic heart failure caused by anterior transmural myocardial infarction. The calculated linear regression equations have high predictive efficiency, which makes it possible to use the amplitude characteristics of the heart cardioelectric field as a marker of the development of chronic heart failure.

Lung-to-Heart Nano-in-Micro Peptide Promotes Cardiac Recovery in a Pig Model of Chronic Heart Failure

BackgroundThe lack of disease-modifying drugs is one of the major unmet needs in patients with heart failure (HF). Peptides are highly selective molecules with the potential to act directly on cardiomyocytes. However, a strategy for effective delivery of therapeutics to the heart is lacking. ObjectivesIn this study, the authors sought to assess tolerability and efficacy of an inhalable lung-to-heart nano-in-micro technology (LungToHeartNIM) for cardiac-specific targeting of a mimetic peptide (MP), a first-in-class for modulating impaired L-type calcium channel (LTCC) trafficking, in a clinically relevant porcine model of HF. MethodsHeart failure with reduced ejection fraction (HFrEF) was induced in Göttingen minipigs by means of tachypacing over 6 weeks. In a setting of overt HFrEF (left ventricular ejection fraction [LVEF] 30% ± 8%), animals were randomized and treatment was started after 4 weeks of tachypacing. HFrEF animals inhaled either a dry powder composed of mannitol-based microparticles embedding biocompatible MP-loaded calcium phosphate nanoparticles (dpCaP-MP) or the LungToHeartNIM only (dpCaP without MP). Efficacy was evaluated with the use of echocardiography, invasive hemodynamics, and biomarker assessment. ResultsDpCaP-MP inhalation restored systolic function, as shown by an absolute LVEF increase over the treatment period of 17% ± 6%, while reversing cardiac remodeling and reducing pulmonary congestion. The effect was recapitulated ex vivo in cardiac myofibrils from treated HF animals. The treatment was well tolerated, and no adverse events occurred. ConclusionsThe overall tolerability of LungToHeartNIM along with the beneficial effects of the LTCC modulator point toward a game-changing treatment for HFrEF patients, also demonstrating the effective delivery of a therapeutic peptide to the diseased heart.

Warming Yang Promoting Blood Circulation and Diuresis Alleviates Myocardial Damage by Inhibiting Collagen Fiber and Myocardial Fibrosis and Attenuating Mitochondria Signaling Pathway Mediated Apoptosis in Chronic Heart Failure Rats.

Warming Yang promoting blood circulation and diuresis (WYPBD) has been proven effective in treating some diseases. This study aimed to evaluate therapeutic effect of WYPBD in treating chronic heart failure (CHF). CHF rats were established by intraperitoneally injecting doxorubicin (DOX). Therapeutic effects of WYPBD on cardiac function and hemodynamic parameters of myocardial tissues were analyzed. Collagen fiber production and myocardial fibrosis were evaluated. Transcriptions of COL1A1 gene, COL3A1 gene, and TGFB1 gene were evaluated with RT-PCR. Expression of BNP, AVP, PARP, caspase-3, and Bcl-2 in myocardial tissues were evaluated. TUNEL assay was used to identify apoptosis of cardiomyocytes. WYPBD alleviated degree of myocardial hypertrophy in CHF rats compared to the rats in CHF model group (P < 0.05). WYPBD significantly improved cardiac hemodynamics (increased LVEF and LVSF) of CHF rats compared to rats in the CHF model group (P < 0.05). WYPBD protected myocardial structure and inhibited collagen fiber production in myocardial tissues of CHF rats. WYPBD markedly decreased myocardial fibrosis mediators (Col1α, Col3α, TGF-β1) transcription in myocardial tissues of CHF rats compared to rats in CHF model group (P < 0.05). WYPBD significantly reduced BNP and AVP expression in myocardial tissues of CHF rats compared to rats in the CHF model group (P < 0.05). WYPBD markedly reduced the expression of PRAP and caspase-3, and increased Bcl-2 expression in myocardial tissues of CHF rats compared to rats in the CHF model group (P < 0.05). In conclusion, WYPBD alleviated CHF myocardial damage by inhibiting collagen fiber and myocardial fibrosis, attenuating apoptosis associated with the mitochondria signaling pathway of cardiomyocytes.

Shenfu Injection improves chronic heart failure by regulating pyroptosis based on NLRP3/caspase-1 pathway

This study investigated the mechanisms and targets of Shenfu Injection in the intervention in chronic heart failure(CHF) through the NOD-like receptor thermal protein domain associated protein 3(NLRP3)/caspase-1 signaling pathway. A CHF model was induced in rats by subcutaneous injection of isoproterenol. Model rats were randomly divided into a model group, a Shenfu Injection group, and a MCC950(NLRP3 inhibitor) group, and a blank group was also set up as a control. After 15 days of treatment, echocardiography was performed to measure cardiac function parameters [left ventricular ejection fraction(LVEF) and left ventricular fractional shortening(LVFS)]. Enzyme-linked immunosorbent assay(ELISA) was used to measure serum levels of N-terminal pro-brain natriuretic peptide(NT-proBNP), interleukin(IL)-1β, and IL-18. Hematoxylin-eosin(HE) and Masson staining were used to observe morphological changes in myocardial tissues, and Western blot was used to measure the expression levels of NLRP3/caspase-1 pathway-related proteins [NLRP3, caspase-1, apoptosis-associated speck-like protein containing a CARD(ASC), gasdermin D(GSDMD), IL-1β, and IL-18]. The study found that isoproterenol-induced CHF in rats resulted in decreased cardiac function, worsened myocardial fibrosis, increased expression levels of NLRP3, ASC, caspase-1, GSDMD-N, IL-1β, and IL-18 in myocardial tissues, elevated serum inflammatory factors, and induced myocardial cell pyroptosis. Following Shenfu Injection intervention, the Shenfu Injection group showed significantly improved LVEF and LVFS, a significant decrease in NT-proBNP, a marked downregulation of NLRP3, ASC, caspase-1, GSDMD-N, IL-1β, and IL-18 protein expression levels, reduced serum inflammatory factors IL-1β and IL-18 expression in CHF rats, and a decrease in the rate of TUNEL-positive cells. Shenfu Injection can significantly improve cardiac function in CHF, inhibit myocardial fibrosis, and alleviate the progression of myocardial cell pyroptosis through the inhibition of the NLRP3/caspase-1 pathway.