Model Of Chronic Heart Failure Research Articles

Synergistic effect on cardiac energetics by targeting the creatine kinase system: in vivo application of high-resolution 31P-CMRS in the mouse

BackgroundPhosphorus cardiovascular magnetic resonance spectroscopy (31P-CMRS) has emerged as an important tool for the preclinical assessment of myocardial energetics in vivo. However, the high rate and diminutive size of the mouse heart is a challenge, resulting in low resolution and poor signal-to-noise. Here we describe a refined high-resolution 31P-CMRS technique and apply it to a novel double transgenic mouse (dTg) with elevated myocardial creatine and creatine kinase (CK) activity. We hypothesised a synergistic effect to augment energetic status, evidenced by an increase in the ratio of phosphocreatine-to-adenosine-triphosphate (PCr/ATP). Methods and resultsSingle transgenic Creatine Transporter overexpressing (CrT-OE, n = 7) and dTg mice (CrT-OE and CK, n = 6) mice were anaesthetised with isoflurane to acquire 31P-CMRS measurements of the left ventricle (LV) utilising a two-dimensional (2D), threefold under-sampled density-weighted chemical shift imaging (2D-CSI) sequence, which provided high-resolution data with nominal voxel size of 8.5 µl within 70 min. (1H-) cine-CMR data for cardiac function assessment were obtained in the same imaging session. Under a separate examination, mice received invasive haemodynamic assessment, after which tissue was collected for biochemical analysis. Myocardial creatine levels were elevated in all mouse hearts, but only dTg exhibited significantly elevated CK activity, resulting in a 51% higher PCr/ATP ratio in heart (3.01 ± 0.96 vs. 2.04 ± 0.57—mean ± SD; dTg vs. CrT-OE), that was absent from adjacent skeletal muscle. No significant differences were observed for any parameters of LV structure and function, confirming that augmentation of CK activity does not have unforeseen consequences for the heart. ConclusionsWe have developed an improved 31P-CMRS methodology for the in vivo assessment of energetics in the murine heart which enabled high-resolution imaging within acceptable scan times. Mice over-expressing both creatine and CK in the heart exhibited a synergistic elevation in PCr/ATP that can now be tested for therapeutic potential in models of chronic heart failure.

Advances in animal models of chronic heart failure and its applications in traditional Chinese medicine

Chronic heart failure(CHF) is a series of clinical syndromes in which various heart diseases progress to their end stage. Its morbidity and mortality are increasing year by year, which seriously threatens people's life and health. The diseases causing CHF are complex and varied, such as coronary heart disease, hypertension, diabetes, cardiomyopathy and so on. It is of great significance to establish animal models of CHF according to different etiologies to explore the pathogenesis of CHF and develop drugs to prevent and treat CHF induced by different diseases. Therefore, based on the classification of the etiology of CHF, this paper summarizes the animal models of CHF widely used in recent 10 years, and the application of these animal models in traditional Chinese medicine(TCM) research, in order to provide ideas and strategies for studying the pathogenesis and treatment of CHF, and provide ideas for TCM modernization research.

Comparative pharmacokinetics of seven bioactive components after oral administration of crude and processed Qixue Shuangbu Prescription in chronic heart failure rats by microdialysis combined with UPLC-MS/MS

Ethnopharmacological relevanceQixue Shuangbu Prescription (QSP) is a classical traditional Chinese medicine prescription, which has widely used for the treatment of chronic heart failure (CHF). Preliminary clinical studies have shown that the efficacy of processed QSP (P-QSP) in treating CHF is greater than crude QSP (C-QSP). However, the pharmacokinetic characteristics of its major bioactive components under pathological conditions are unclear. Aim of studyThis study aims to compare pharmacokinetics of seven bioactive components after oral administration of C-QSP and P-QSP in CHF model rats. Materials and methodsGinsenoside Rb1, ginsenoside Re, ginsenoside Rg1, ferulic acid, astragaloside IV, calycosin-7-O-β-D-glucoside, and paeoniflorin in QSP were used as the target components. CHF model in rats was induced by the intraperitoneal injection of doxorubicin. A microdialysis combined with UPLC-MS/MS method was first established to compare the pharmacokinetics of seven major bioactive components in CHF model rats after oral administration of C-QSP and P-QSP. ResultsThis method was successfully applied to the pharmacokinetic investigation of seven major components of C-QSP and P-QSP following oral administration in CHF model rats. Compared with the C-QSP group, the Cmax, AUC0-t and AUC0−∞ of ginsenoside Rb1, ginsenoside Re, ginsenoside Rg1, ferulic acid, astragaloside IV and paeoniflorin significantly increased (P < 0.05) in the P-QSP group, which suggested that the absorptivity and bioavailability were increased. Lower T1/2, MRT0−t of ginsenoside Rb1, gerulic acid and higher T1/2, MRT0−t of ginsenoside Rb1, astragaloside IV, paeoniflorin in the P-QSP group, which indicated that eliminated more quickly or slowly, respectively. ConclusionsThe pharmacokinetic parameters of bioactive components were significantly changed for better bioavailability and absorption, longer lasting time elimination, which were beneficial for enhancing therapeutic efficacy in the P-QSP group. This study will provide a new perspective to explain the pharmacokinetic-pharmacodynamic correlation of P-QSP on the treatment of CHF.

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.

Evaluation of the Effectiveness and Reproducibility of Biological Models of Chronic Heart Failure

Evaluation of the Effectiveness and Reproducibility of Biological Models of Chronic Heart Failure

Simvastatin attenuates the c-Raf/Erk and calcineurin-NFATc2 pathways via inhibition of Hsp90 activity during the development of heart failure

Hsp90 is a molecular chaperone that contributes to the activation and stabilization of client proteins. In our previous studies, we found that inhibition of Hsp90 delayed cardiac remodeling during the development of chronic heart failure in animal models. Simvastatin, an inhibitor of HMG-CoA reductase, has been shown to inhibit Hsp90. However, it is unclear whether simvastatin can prevent cardiac remodeling by inhibiting Hsp90. Therefore, the effects of simvastatin were examined in a rat model of chronic heart failure following myocardial infarction. The results showed that simvastatin reduced cardiac remodeling by inhibiting cardiac fibrosis. Furthermore, simvastatin decreased the expression of c-Raf and calcineurin, which are involved in intracellular signaling during the development of myocardial remodeling. In vitro, we found that the interaction of Hsp90 with c-Raf and calcineurin was reduced and the expression levels these client proteins were decreased in fibroblasts cultured in the presence of simvastatin. In addition, simvastatin also reduced proliferation, migration, and collagen production of fibroblasts. These results suggest that Hsp90 inhibition is partly responsible for the inhibitory effect of simvastatin on the development of myocardial remodeling.

Nuanxinkang prevents the development of myocardial infarction-induced chronic heart failure by promoting PINK1/Parkin-mediated mitophagy

BackgroundMitochondrial dysfunction is an important pathological feature of chronic heart failure (CHF). Regulation of mitophagy can effectively maintain mitochondrial homeostasis and energy metabolism, thereby inhibiting the development of CHF. Nuanxinkang (NXK), a Chinese herbal compound preparation, has significant cardioprotective effects on CHF; however, its underlying mechanism on mitophagy has not been completely clarified. This research intended to investigate the mechanism of NXK in treating myocardial infarction (MI)-induced CHF. MethodsThe left anterior descending coronary artery (LAD) ligation surgery was performed to establish an MI-induced CHF model in male C57BL/6 mice. From 1 day after surgery, mice were given NXK (0.41, 0.82 or 1.65 g/kg/d), Perindopril (PDPL, 0.607 mg/kg/d), or an equivalent amount of sterile water by gavage for 28 continuous days. Then, mice were examined for cardiac function, myocardial fibrosis, cardiomyocyte apoptosis, mitochondrial structure and mitophagy levels of cardiomyocytes, etc. In addition, a hypoxic injury model was created using HL-1 cardiomyocytes from wild-type (WT) mice. HL-1 cells were pretreated with or without NXK-containing serum. Mitochondrial function and mitophagy levels were examined in HL-1 cells. ResultsIn MI-induced CHF mice, cardiac dysfunction, severe cardiac remodeling, elevated levels of oxidative stress, reduced ATP levels, and inhibition of PINK1/Parkin-mediated mitophagy were observed. High-dose NXK treatment (1.65 g/kg/d) significantly improved myocardial energy metabolism, inhibited cardiac remodeling, improved cardiac function, and restored cardiac PINK1/Parkin-mediated mitophagy levels to some extent in MI mice. In vitro, elevated levels of mitochondrial reactive oxygen species (ROS) with impaired mitochondrial membrane potential (ΔΨm) were observed in hypoxic HL-1 cells. While NXK treatment significantly protected cardiomyocytes from hypoxia-induced mitochondrial dysfunction, which is consistent with the in vivo results. Further studies showed that NXK could increase PINK1/Parkin-mediated mitophagy levels in cardiomyocytes, which could be blocked by the mitophagy inhibitor Mdivi-1. ConclusionIn conclusion, NXK could prevent cardiac mitochondrial dysfunction and improve cardiac function against MI-induced CHF by promoting Pink1/Parkin-mediated mitophagy, which represents a very prospective strategy for the treatment of CHF.

Protective effect of Shenfu Injection on rats with chronic heart failure based on HMGB1/TLR4/NF-κB signaling pathway

The study aimed to explore the mechanism and targets of Shenfu Injection in the regulation of inflammatory injury in chronic heart failure rats based on the high mobility group box-1/Toll like receptor 4/nuclear factor kappa-B(HMGB1/TLR4/NF-κB) signaling pathway. The rat model of chronic heart failure was established using isoproterenol. The modeled rats were divided into three groups by random number table: the model group, Shenfu group and glycopyrrolate group, and the normal group was also set. The rats were administrated for 15 consecutive days, and on the following day after the last administration, they were sacrificed for sample collection. The cardiac mass index and left ventricular mass index of the rats in each group were measured, and the echocardiogram was used to analyze the cardiac function indices, and ELISA to test the inflammatory indices in rat serum. The pathological morphology and fibrosis status of rat heart tissues were observed by HE staining and Masson staining, respectively. The content of HMGB1 was determined by immunofluorescence staining. The protein and mRNA expression of HMGB1/TLR4/TLR4 signaling pathway was detected by Western blot and RT-qPCR, respectively. The results showed that the chronic heart failure rat model was successfully prepared. The rats in the model group had reduced cardiac function, increased levels of HMGB1 and inflammatory factors(P&lt;0.05), and elevated protein and mRNA expression of HMGB1, TLR4, MyD88, and NF-κB P65 in myocardial tissue(P&lt;0.05), with fibrous connective tissue hyperplasia, inflammatory cell infiltration and severe fibrosis. Shenfu Injection improved cardiac function, decreased the levels of HMGB1 and inflammatory factors(P&lt;0.05) and the protein and mRNA expression of HMGB1, TLR4, MyD88, and NF-κB P65 in myocardial tissue(P&lt;0.05), ameliorated interstitial fibrous connective tissue hyperplasia and inflammatory cell infiltration, and reduced fibrosis. In conclusion, Shenfu Injection can reduce inflammatory damage and improve cardiac function in chronic heart failure rats by regulating the HMGB1/TLR4/NF-κB signaling pathway.

Effect of injection of different doses of isoproterenol on the hearts of mice

BackgroundHeart failure (HF) is one of the diseases that seriously threaten human health today and its mechanisms are very complex. Our study aims to confirm the optimal dose ISO-induced chronic heart failure mice model for better study of HF-related mechanisms and treatments in the future.MethodsC57BL/6 mice were used to establish mice model of chronic heart failure. We injected isoproterenol subcutaneously in a dose gradient of 250 mg/kg, 200 mg/kg, 150 mg/kg, 100 mg/kg and 50 mg/kg. Echocardiography and ELISA were performed to figure out the occurrence of HF. We also supplemented the echocardiographic changes in mice over 30 days.ResultsExcept group S and group E, echocardiographic abnormalities were found in other groups, suggesting a decrease in cardiac function. Except group S, myofibrolysis were found in the hearts of mice in other groups. Brain natriuretic peptide was significantly increased in groups B and D, and C-reactive protein was significantly increased in each group.ConclusionOur research finally found that the HFrEF mice model created by injection at a dose of 100 mg/kg for 7 days was the most suitable and a relatively stable chronic heart failure model could be obtained by placing it for 21 days.

Activation of the sigma-1 receptor exerts cardioprotection in a rodent model of chronic heart failure by stimulation of angiogenesis

BackgroundAngiogenesis plays a critical role on post-infarction heart failure (PIHF), the presence of which facilitates additional blood supply to maintain the survival of residual cardiomyocytes. The sigma-1 receptor (S1R) has been substantiated to stimulate angiogenesis, with the effect on a model of PIHF remaining unknown.AimsThis study aims to investigate the effects of S1R on PIHF and the underlying mechanisms involved.MethodsRats were implemented left anterior descending artery ligation followed by rearing for 6 weeks to induce a phenotype of heart failure. Daily intraperitoneal injection of S1R agonist or antagonist for 5 weeks was applied from 2nd week after surgery. The effects exerted by S1R were detected by echocardiography, hemodynamic testing, western blot, Sirius red dyeing, ELISA, immunohistochemistry and fluorescence. We also cultured HUVECs to verify the mechanisms in vitro.ResultsStimulation of S1R significantly ameliorated the cardiac function resulted from PIHF, in addition to the observation of reduced fibrosis in the peri-infarct region and the apoptosis of residual cardiomyocytes, which were associated with augmentation of microvascular density in peri-infarct region through activation of the JAK2/STAT3 pathway. We also indicated that suppression of JAK2/STAT3 pathway by specific inhibitor in vitro reversed the pro-angiogenic effects of S1R on HUVECs, which further confirmed that angiogenesis, responsible for PIHF amelioration, by S1R stimulation was in a JAK2/STAT3 pathway-dependent manner.ConclusionS1R stimulation improved PIHF-induced cardiac dysfunction and ventricular remodeling through promoting angiogenesis by activating the JAK2/STAT3 pathway.

Investigation into the protective effects of hypaconitine and glycyrrhetinic acid against chronic heart failure of the rats

BackgroundThe present study aimed to determine the protective effects of hypaconitine (HA) and glycyrrhetinic acid (GA) against chronic heart failure (CHF) in the rats and to explore the underlying molecular mechanisms.MethodsThe CHF rat model was established by transverse-aortic constriction (TAC) operation. Transthoracic echocardiography and hematoxylin eosin (HE) staining were used to evaluate the pathophysiological and histopathological changes of CHF model. The total cholesterol (TCHO) and triglyceride (TG) levels were determined by ELISA assay. The protein expression of fibroblast growth factor 2 (FGF2), vascular endothelial growth factor A (VEGFA) and endothelial nitric oxide synthase (eNOS) in the rat ventricular tissues was determined by immunohistochemistry. The serum metabolites were determined by LC-MS/MS assay.ResultsAfter applied the HA + GA, the cardiac tissue and structure were obviously improved, and the HA + GA treatment also significantly reduced the plasma levels of TCHO and TG in the CHF rats. The expression of FGF2 and VEGFA protein was up-regulated and the expression of eNOS protein was down-regulated in the ventricular tissues of CHF rats, which was significantly restored after HA + GA treatment. HA + GA treatment down-regulated serum isonicotinic acid, phosphatidylcholine, cardiolipin, estrogen glucuronide, and glycocholic acid, up-regulated serum sphingosine and deoxycholic acid in the CHF rats.ConclusionsIn conclusion, HA + GA showed protective effects on CHF in the rats, and the HA + GA may exert protective effects by reducing lipid levels, up-regulating the expression of FGF2 and VEGFA proteins, attenuating eNOS protein expression, and modulating metabolic pathways. However, the molecular mechanisms underlying HA + GA-mediated effects still require further examination.

Cardiac Spinal Afferent Denervation Attenuates Renal Dysfunction in Rats With Cardiorenal Syndrome Type 2

Cardiorenal syndrome type 2 (CRS2) is defined as a chronic cardiovascular disease, usually chronic heart failure (CHF), resulting in chronic kidney disease. We hypothesized that the cardiac spinal afferent reflex (CSAR) plays a critical role in the development of CRS2. Our data suggest that cardiac afferent ablation by resiniferatoxin not only improves cardiac function but also benefits the kidneys and increases long-term survival in the myocardial infarction model of CHF. We also found that renal denervation has a similar reno-protective effect in CHF rats. We believe this novel work contributes to the development of a unique neuromodulation therapy to treat CHF patients.

Dapagliflozin Attenuates Myocardial Fibrosis by Inhibiting the TGF-β1/Smad Signaling Pathway in a Normoglycemic Rabbit Model of Chronic Heart Failure.

Recent studies have shown that sodium-glucose cotransporter-2 (SGLT2) inhibitors play a beneficial role for normoglycemic patients with heart failure (HF). However, the underlying mechanism remains largely unexplored. In the present study, we aimed to investigate the cardioprotective effect of SGLT2 inhibitors in a normoglycemic rabbit model of chronic heart failure (CHF) and its potential mechanism was also explored. A total of 24 male New Zealand white rabbits were randomly divided into the sham group, HF group, perindopril group, and dapagliflozin (DAPA) group. The normoglycemic CHF model was established by aortic constriction for 12 weeks. In the 13th week, DAPA (1 mg/kg/day) or perindopril (0.5 mg/kg/day) was administered by oral gavage daily for 10 weeks. Both the sham group and HF group were given normal saline via gavage. After 10 weeks, the heart structure and function were evaluated by echocardiography and plasma NT-proBNP. Moreover, cardiac fibrosis was analyzed using immunohistochemistry, Masson’s trichrome staining, and Western blotting analysis. The results showed that DAPA improved the myocardial structure and function of normoglycemic CHF rabbits and ameliorated myocardial fibrosis. Further study indicated that DAPA suppressed cardiac fibrosis by inhibiting the transforming growth factor β1 (TGF-β1)/Smad signaling pathway. Collectively, our findings showed that DAPA could ameliorate cardiac fibrosis in normoglycemic CHF rabbits by inhibiting the TGF-β1/Smad signaling pathway.

Human umbilical cord-derived stem cell sheets improve left ventricular function in rat models of ischemic heart failure

IntroductionHuman umbilical cord-derived mesenchymal stem cells (UC-MSCs) are among the most promising cell therapy sources used to treat ischemic heart disease. Cell sheet engineering has been used to transplant stem cells and improve their therapeutic effectiveness. We aimed to evaluate the effectiveness of UC-MSC sheets in the treatment of chronic ischemic heart failure. Methods and resultsFlow cytometric analysis showed that UC-MSCs were positive for CD73, CD90, and CD105. UC-MSC sheets were produced from UC-MSCs using temperature-responsive culture dishes. Afterward, these sheets were transplanted onto the epicardial surface at the infarct heart in rat models of chronic ischemic heart failure. At four weeks after the transplantation, echocardiography analysis revealed that the cardiac function of the UC-MSC sheets group was significantly better than that of the suspension and myocardial infarction (MI) only groups. Furthermore, histological examinations revealed that the left ventricular remodeling was attenuated compared with the suspension and MI-only groups. In the UC-MSC slice group, the neovascular den and cell size in the infarct margin region were was significantly improved than in the suspension and MI-only groups. Also, the UC-MSC sheets inhibited the PI3K/AKT/mTOR signaling pathway in chronic ischemic heart failure. ConclusionsUC-MSC sheets can maintain cardiac function and attenuate ventricular remodeling in chronic ischemic heart failure, indicating that this strategy would be a promising therapeutic option in the clinical scenario.

Epigallocatechin-3-gallate exerts cardioprotective effects related to energy metabolism in pressure overload-induced cardiac dysfunction

BackgroundTo investigate the mechanisms of potential cardioprotective effects of epigallocatechin-3-gallate (EGCG) in pressure overload-induced cardiac dysfunction. MethodsA chronic heart failure model was established using abdominal aortic constriction (AAC) surgery, rats were divided into sham, AAC, and AAC + EGCG groups. Echocardiography and tissue section staining were performed to evaluate cardiac function and pathology, respectively. Gene expression level were detected with quantitative real-time polymerase chain reactions. Label-free quantitative proteomics was used to investigate the whole proteomes of heart, and the differentially expressed proteins were analyzed using bioinformatics methods. Western blot was performed to validate the levels and the reliability of the differential proteins. ResultsCompared with the AAC group, systolic dysfunction was improved in AAC + EGCG group after EGCG treatment. EGCG inhibited myocardial fibrosis and cardiac hypertrophy after AAC, along with reducing atrial natriuretic protein, B-type natriuretic peptide, collagen types 1 and 3 alpha 1, and transforming growth factor β-1. Quantitative proteomics identified a total of 162 differentially expressed proteins, among them, 18 were closely related to cardiovascular disorders. Bioinformatics analyses showed that EGCG played a therapeutic role mainly by changing energy metabolism processes, such as oxidative phosphorylation and lipid metabolism. Furthermore, NADH: ubiquinone oxidoreductase subunit S4, an important component of the mitochondrial respiratory chain, was increased after AAC and then reversed by EGCG, which was consistent with the proteomics results. ConclusionsEGCG may correct cardiac systolic dysfunction and prevent cardiac remodeling after heart failure via enhancing the energy metabolism, which provides us with new insights into cardioprotective effects of EGCG related to the energy metabolisms in pressure overload-induced cardiac dysfunction.

Cardiac contractility modulation ameliorates myocardial metabolic remodeling in a rabbit model of chronic heart failure through activation of AMPK and PPAR-α pathway.

Metabolic remodeling contributes to the pathological process of heart failure (HF). We explored the effects of cardiac contractility modulation (CCM) on myocardial metabolic remodeling in the rabbit model with HF. The HF in rabbit model was established by pressure uploading and then CCM was applied. We evaluated the cardiac structure and function by echocardiography, serum BNP level, and hematoxylin and eosin and Masson’s trichrome staining. We detected the accumulation of glycogen and lipid droplets in myocardial tissues by periodic acid-Schiff and Oil Red O staining. Then, we measured the contents of glucose, free fatty acid (FFA), lactic acid, pyruvate, and adenosine triphosphate (ATP) levels in myocardial tissues by corresponding kits and the expression levels of key factors related to myocardial substrate uptake and utilization by western blotting were analyzed. CCM significantly restored the cardiac structure and function in the rabbit model with HF. CCM therapy further decreased the accumulation of glycogen and lipid droplets. Furthermore, CCM reduced the contents of FFA, glucose, and lactic acid, and increased pyruvate and ATP levels in HF tissues. The protein expression levels related to myocardial substrate uptake and utilization were markedly improved with CCM treatment by further activating adenosine monophosphate-activated protein kinase and peroxisome proliferator-activated receptor-α signaling pathways.

Chronic, Combined Cardiac and Renal Dysfunction Exacerbates Renal Venous Pressure-Induced Suppression of Renal Function in Rats.

Background and ObjectiveIncreased renal venous pressure (RVP) is common in combined heart and kidney failure. We previously showed that acute RVP elevation depresses renal blood flow (RBF), glomerular filtration rate (GFR), and induces renal vasoconstriction in the absence of changes in blood pressure in healthy rats. We used our established rodent model of chronic combined heart and kidney failure (H/KF) to test whether RVP elevation would impair cardiovascular stability, renal perfusion and exacerbate renal dysfunction.MethodsMale rats were subjected to 5/6 nephrectomy (SNx or Sham) and 6% high salt diet followed 7 weeks later by ligation of the left anterior descending coronary artery (CL or Sham). Experimental groups: CL + SNx (n = 12), Sham CL + SNx (n = 9), CL+ Sham SNx (n = 6), and Sham Control (n = 6). Six weeks later, anesthetized rats were subjected to an acute experiment whereupon mean arterial pressure (MAP), heart rate (HR), RVP, RBF, and GFR were measured at baseline and during elevation of RVP to 20–25 mmHg for 120 min.ResultsBaseline MAP, HR, RBF, and renal vascular conductance (RVC) were comparable among groups. Baseline GFR was significantly depressed in CL + SNx and Sham CL + SNx groups compared to Sham Control and CL + Sham SNx groups. Upon RVP increase, MAP and HR fell in all groups. Increased RVP exacerbated the reduction in RBF in CL + SNx (−6.4 ± 0.9 ml/min) compared to Sham Control (−3.7 ± 0.9 ml/min, p < 0.05) with intermediate responses in Sham CL + SNx (−6.8 ± 1.3 ml/min) and CL + Sham SNx (−5.1 ± 0.4 ml/min) groups. RVP increase virtually eliminated GFR in CL + SNx (−99 ± 1%), Sham CL + SNx (−95 ± 5%), and CL + Sham SNx (−100%) groups compared to Sham Control (−84 ± 15% from baseline; p < 0.05). Renal vascular conductance dropped significantly upon RVP increase in rats with HF (CL + SNx: −0.035 ± 0.011; CL + Sham SNx: −0.050 ± 0.005 ml/min·mmHg−1, p < 0.05) but not Sham CL + SNx (−0.001 ± 0.019 ml/min·mmHg−1) or Control (−0.033 ± mL/min·mmHg−1).ConclusionChronic combined heart and kidney failure primarily impairs renal hemodynamic stability in response to elevated RVP compared to healthy rats.

MiR-129-5p restores cardiac function in rats with chronic heart failure by targeting the E3 ubiquitin ligase Smurf1 and promoting PTEN expression

ABSTRACT Chronic heart failure (CHF) is a prevalent health concern with complex pathogenesis. This current study set out to estimate the function of the miR-129-5p/Smurf1/PTEN axis on cardiac function injury in CHF. The model of CHF in rats was established. The cardiac function indexes, myocardial tissue damage, and oxidative stress-related factors in CHF rats were evaluated after the interference of Smurf1/miR-129-5p/PTEN. The targeting relationships between miR-129-5p and Smurf1 and between PTEN and Smurf1 were verified. It was found that that after modeling, cardiac functions were impaired, heart/left ventricular/lung weight and the myocardial structure was destroyed, and the degree of fibrosis of myocardial tissue was increased. After Smurf1 knockdown, the cardiac function, myocardial structure, and oxidative stress were improved, and the fibrosis in myocardial tissue was decreased. Smurf1 was a target of miR-129-5p. miR-129-5p could annul the protective effect of Smurf1 silencing on CHF rats. Smurf1 inhibited PTEN expression by promoting PTEN ubiquitination, while miR-129-5p enhanced PTEN expression by inhibiting Smurf1. Meanwhile, overexpression of PTEN annulled the cardiac dysfunction in CHF rats induced by Smurf1. In conclusion, miR-129-5p targeted Smurf1 and repressed the ubiquitination of PTEN, and promoted PTEN expression, thus improving the cardiac function of CHF rats.

Perspective on the development of a bioengineered patch to treat heart failure: rationale and proposed design of phase I clinical trial

This perspective focuses on the development of tissue engineered (TE) cell-based therapies to treat left ventricular (LV) dysfunction and chronic heart failure (CHF). The development of induced pluripotent stem cells enabled investigators to seed or co-culture human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) alone and in combination with other cells onto bioengineered scaffolds applied to the epicardial surface of the damaged left ventricle. Using our work as an example, we show how a xenograft implant of a bioengineered scaffold embedded with human neonatal fibroblasts and seeded with hiPSC-CMs partially reversed maladaptive LV remodeling and improved LV systolic/diastolic function in an immune-competent rat model of CHF. The fibroblasts lay down an extracellular matrix and secrete growth factors that increase myocardial blood flow. This approach provides an improved cell payload that covers a larger area of the damaged left ventricle as opposed to direct cell injections into the heart or down the coronary arteries. These studies combined with ongoing studies in immune-competent Yucatan mini swine treated with the same xenograft led to the preliminary design of a proposed Phase I clinical trial that will be presented to the Federal Drug Administration. For the proposed Phase I clinical, this TE patch will be implanted onto the epicardial surface of non-immunosuppressed patients undergoing elective Coronary Artery Bypass Grafting with Ejection Fractions ≥ 20% and ≤ 45%. The primary endpoints will be adverse events/severe adverse events associated with placing the TE patch on the heart. While Phase I trials are primarily safety trials, this proposed trial is designed to obtain some potential efficacy endpoints to help with the design of future Phase II/III clinical trials. These endpoints include changes in LV remodeling that were seen in the pre-clinical animal models as well as including endpoints that focus on patient well-being.

Shexiang Tongxin Dropping Pill Protects Against Chronic Heart Failure in Mice via Inhibiting the ERK/MAPK and TGF-β Signaling Pathways.

Background: Chronic heart failure (CHF) is a major public health problem with high mortality and morbidity worldwide. Shexiang Tongxin Dropping Pill (STDP) is a widely used traditional Chinese medicine preparation for coronary heart disease and growing evidence proves that STDP exerts beneficial effects on CHF in the clinic. However, the molecular mechanism of the therapeutic effects of STDP on CHF remains largely unknown. Objective: This study aimed to elucidate the mechanism of action of STDP against CHF by integrating network pharmacology analysis and whole-transcriptome sequencing. Methods: First, the mouse model of CHF was established by the transverse aortic constriction (TAC) surgery, and the efficacy of STDP against CHF was evaluated by assessing the alterations in cardiac function, myocardial fibrosis, and cardiomyocyte hypertrophy with echocardiography, Masson’s trichrome staining, and wheat germ agglutinin staining. Next, a CHF disease network was constructed by integrating cardiovascular disease-related genes and the transcriptome sequencing data, which was used to explore the underlying mechanism of action of STDP. Then, the key targets involved in the effects of STDP on CHF were determined by network analysis algorithms, and pathway enrichment analysis was performed to these key genes. Finally, important targets in critical pathway were verified in vivo. Results: STDP administration obviously improved cardiac function, relieved cardiomyocyte hypertrophy, and ameliorated myocardial fibrosis in CHF mice. Moreover, STDP significantly reversed the imbalanced genes that belong to the disease network of CHF in mice with TAC, and the number of genes with the reverse effect was 395. Pathway analysis of the crucial genes with recovery efficiency revealed that pathways related to fibrosis and energy metabolism were highly enriched, while TGF-β pathway and ERK/MAPK pathway were predicted to be significantly affected. Consistently, validation experiments confirmed that inhibiting ERK/MAPK and TGF-β signaling pathways via reduction of the phosphorylation level of Smad3 and ERK1/2 is the important mechanism of STDP against CHF. Conclusion: Our data demonstrated that STDP can recover the imbalanced CHF network disturbed by the modeling of TAC through the multi-target and multi-pathway manner in mice, and the mechanisms are mainly related to inhibition of ERK/MAPK and TGF-β signaling pathways.