Antisense Therapy Attenuates Phospholamban p.(Arg14del) Cardiomyopathy in Mice and Reverses Protein Aggregation.

Inherited cardiomyopathy caused by the p.(Arg14del) pathogenic variant of the phospholamban (PLN) gene is characterized by intracardiomyocyte PLN aggregation and can lead to severe dilated cardiomyopathy. We recently reported that pre-emptive depletion of PLN attenuated heart failure (HF) in several cardiomyopathy models. Here, we investigated if administration of a Pln-targeting antisense oligonucleotide (ASO) could halt or reverse disease progression in mice with advanced PLN-R14del cardiomyopathy. To this aim, homozygous PLN-R14del (PLN-R14 Δ/Δ) mice received PLN-ASO injections starting at 5 or 6 weeks of age, in the presence of moderate or severe HF, respectively. Mice were monitored for another 4 months with echocardiographic analyses at several timepoints, after which cardiac tissues were examined for pathological remodeling. We found that vehicle-treated PLN-R14 Δ/Δ mice continued to develop severe HF, and reached a humane endpoint at 8.1 ± 0.5 weeks of age. Both early and late PLN-ASO administration halted further cardiac remodeling and dysfunction shortly after treatment start, resulting in a life span extension to at least 22 weeks of age. Earlier treatment initiation halted disease development sooner, resulting in better heart function and less remodeling at the study endpoint. PLN-ASO treatment almost completely eliminated PLN aggregates, and normalized levels of autophagic proteins. In conclusion, these findings indicate that PLN-ASO therapy may have beneficial outcomes in PLN-R14del cardiomyopathy when administered after disease onset. Although existing tissue damage was not reversed, further cardiomyopathy progression was stopped, and PLN aggregates were resolved.

Doxorubicin induces wide-spread transcriptional changes in the myocardium of hearts distinguishing between mice with preserved and impaired cardiac function.

AIMS: Doxorubicin (DOX) is an important drug for the treatment of various tumor entities. However, the occurrence of heart failure limits its application. This study investigated differential gene expression profiles in the left and right ventricles of DOX treated mice with either preserved or impaired myocardial function. We provide new mechanistic insights into the pathophysiology of DOX-induced heart failure and have discovered pathways that counteract DOX-induced cardiotoxicity. MAIN METHODS: We used in total 48 male mice and applied a chronic low dose DOX administration (5 mg/kg per injection, in total 20 mg/kg over 4 weeks) to induce heart failure. Echocardiographic parameters were evaluated one week after the final dose and mice were separated according to functional parameters into doxorubicin responding and non-responding animals. Post mortem, measurements of reactive oxygen species (ROS) and gene expression profiling was performed in separated right and left hearts. KEY FINDINGS: We detected significant ROS production in the left heart of the mice in response to DOX treatment, although interestingly, not in the right heart. We found that transcriptional changes differ between right and left heart correlating with the occurrence of myocardial dysfunction. SIGNIFICANCE: Doxorubicin induces changes in gene expression in the entire heart of animals without necessarily impairing cardiac function. We identified a set of transcripts that are associated with DOX cardiotoxicity. These might represent promising targets to ameliorate DOX-induced heart failure. Moreover, our results emphasize that parameters of left and right heart function should be evaluated during standardized echocardiography in patients undergoing DOX therapy.

Liquiritigenin attenuates isoprenaline­induced myocardial fibrosis in mice through the TGF­ß1/Smad2 and AKT/ERK signaling pathways.

Myocardial fibrosis is a pathological process characterized by excessive accumulation of extracellular matrix in myocardial interstitial spaces. Myocardial fibrosis is a fundamental process in ventricular remodeling and a primary contributor to the progression of heart failure. Liquiritigenin (LQ) is a flavanone compound with anti­oxidative, anti­carcinogenic, anti­inflammatory and estrogenic properties. The present study aimed to investigate the regulatory potential of LQ treatment in a mouse model of isoprenaline (ISO)­induced cardiac fibrosis and in cultured H9C2 cardiomyocytes stimulated with angiotensin II (Ang II). The treatment of ISO­induced mice with LQ significantly decreased the levels of cardiac injury­related proteins in the serum and ECM accumulation in mouse heart tissues. LQ treatment also effectively alleviated cardiac dysfunction in ISO­treated mice. Further analyses revealed that LQ inhibited ISO­induced collagen formation and activation of the transforming growth factor­ß1 (TGF­ß1)/Smad2 and protein kinase B (AKT)/extracellular signal­regulated kinase (ERK) signaling pathways. As a major pathological event in myocardial fibrosis, the apoptosis of cardiomyocytes has been considered a key mechanism contributing to impaired left ventricle performance. The pretreatment of rat cardiomyocytes with LQ significantly reduced the apoptosis of H9C2 cells, and inhibited Ang II­induced activation of the TGF­ß1/Smad2 and AKT/ERK pathways. In conclusion, the present study revealed that LQ ameliorated ISO­induced myocardial fibrosis in mice and inhibited the apoptosis of cardiomyocytes in vitro by inhibiting the TGF­ß1/Smad2 and AKT/ERK signaling pathways. These results suggested the anti­fibrotic and cardioprotective potential of LQ in fibrosis, thus supporting the use of LQ for the management of cardiomyocyte injury and myocardial fibrosis in patients with cardiac diseases.

Thorough QT/QTc Evaluation of the Cardiac Safety of Enarodustat (JTZ-951), an Oral Erythropoiesis-Stimulating Agent, in Healthy Adults.

This study evaluated the effect of enarodustat on cardiac repolarization in healthy subjects. Enarodustat (20 and 150 mg [supratherapeutic dose]), placebo, and moxifloxacin (positive control, 400 mg) were administered orally to males and females (N = 54) in a crossover fashion. Continuous 12-lead Holter electrocardiogram (ECG) data were obtained before and after dosing, and blood samples were obtained for pharmacokinetic assessments of enarodustat, its circulating metabolite (R)-M2, and moxifloxacin. Central tendency analysis was performed for relevant ECG parameters, the relationship between individual-corrected interval from beginning of the QRS complex to end of the T wave in the frontal plane (QTcI, the primary end point) and plasma concentrations of enarodustat and (R)-M2 were assessed, and ECG waveforms were evaluated for morphological changes. The supratherapeutic dose resulted in 7- and 9-fold higher geometric mean maximum concentrations for enarodustat and (R)-M2, respectively, than the 20 mg dose. Based on time point analysis, the upper bound of the 2-sided 90% confidence interval (CI) for QTcI did not exceed 10 milliseconds at any of the time points for either dose. Based on QTcI-concentration analysis, the slopes for enarodustat and (R)-M2 were not statistically different than 0, and the upper bounds of the 2-sided 90% CI for QTcI at the geometric mean maximum concentrations for the supratherapeutic dose were 1.97 and 1.68 milliseconds for enarodustat and (R)-M2, respectively. The lower bound of the 2-sided 90% CI for moxifloxacin was ≥5 milliseconds, demonstrating assay sensitivity. The study demonstrated no clinically relevant effect of enarodustat and (R)-M2 on cardiac repolarization. There was no evidence of any clinically significant effect on the PR interval and QRS duration, and ECG waveforms showed no new clinically relevant morphological changes.

Hydrogen Sulfide Restored the Diurnal Variation in Cardiac Function of Aging Mice.

The present study was performed to investigate whether H2S could restore the diurnal variation in cardiac function of aging mice and explore the potential mechanisms. We found that ejection fraction (EF) and fractional shortening (FS) in 3-month-old mice exhibited diurnal variations over a 24-hour period. However, the diurnal variations were disrupted in 18-month-old mice, and there was a decline in EF and FS. In addition, the plasma malondialdehyde (MDA) levels were increased, and H2S concentrations and superoxide dismutase (SOD) activities were decreased in 18-month-old mice. Then, CSE KO mice were used to determine if there was a relationship between endogenous H2S and diurnal variations in EF and FS. There was no difference in 12-hour averaged EF and FS between dark and light periods in CSE KO mice accompanying increased MDA levels and decreased SOD activities in plasma, indicating that deficiency of endogenous H2S blunted diurnal variations of cardiac function. To determine whether oxidative stress disrupted the diurnal variations in cardiac function, D-galactose-induced subacute aging mice were employed. After 3-month D-gal treatment, both 12-hour averaged EF and FS in dark or light periods were decreased; meanwhile, there was no difference in 12-hour averaged EF and FS between dark and light periods. After 3-month NaHS treatment in the D-gal group, the plasma MDA levels were decreased and SOD activities were increased. The EF and FS were lower during the 12-hour light period than those during the 12-hour dark period which was fit to sine curves in the D-gal+NaHS group. Identical findings were also observed in 18-month-old mice. In conclusion, our studies revealed that the disrupted diurnal variation in cardiac function was associated with increased oxidative stress and decreased H2S levels in aging mice. H2S could restore the diurnal variation in cardiac function of aging mice by reducing oxidative stress.

Phase 1 Concentration-QTc and Cardiac Safety Analysis of the MDM2 Antagonist KRT-232 in Patients With Advanced Solid Tumors, Multiple Myeloma, or Acute Myeloid Leukemia.

Cardiac safety and plasma concentration-QTc interval analyses were completed using data from 2 phase 1 studies of the selective mouse double minute chromosome 2 antagonist, KRT-232, in patients with solid tumors or multiple myeloma and acute myeloid leukemia (AML) who received KRT-232 doses of 15 to 480 mg once daily (QD; N = 130). A linear mixed-effects model related change from baseline Fridericia-corrected QT interval (ΔQTcF) to KRT-232 plasma concentrations. The final model included parameters for the intercept (with between-subject variability), KRT-232 concentration-ΔQTcF slope, and baseline QTcF effect on the intercept. Diagnostic plots indicated an adequate model fit. Mean (90% confidence interval) predicted ΔQTcF values at the maximum clinical dose (480 mg QD) were 2.04 (0.49-3.60) milliseconds for patients with solid tumors and 4.52 (2.35-6.69) milliseconds for patients with AML. Because the 90% confidence interval upper bound of the mean ΔQTcF was predicted to be below 10 milliseconds at doses up to 480 mg QD in patients with solid tumors, multiple myeloma, or AML, KRT-232 does not result in clinically meaningful QT prolongation at the doses currently under investigation in clinical trials. No significant cardiac safety concerns were identified at these doses.

Garlic Derived Diallyl Trisulfide in Experimental Metabolic Syndrome: Metabolic Effects and Cardioprotective Role.

This study aimed to examine the effects of diallyl trisulfide (DATS), the most potent polysulfide derived from garlic, on metabolic syndrome and myocardial function in rats with metabolic syndrome (MetS). For that purpose, we used 36 male Wistar albino rats divided into control rats, rats with MetS and MetS rats treated with 40 mg/kg of DATS every second day for 3 weeks. In the first part, we studied the impact of DATS on MetS control and found that DATS significantly raised H2S, decreased homocysteine and glucose levels and enhanced lipid and antioxidative, while reducing prooxidative parameters. Additionally, this polysulfide improved cardiac function. In the second part, we investigated the impact of DATS on ex vivo induced ischemia/reperfusion (I/R) heart injury and found that DATS consumption significantly improved cardiodynamic parameters and prevented oxidative and histo-architectural variation in the heart. In addition, DATS significantly increased relative gene expression of eNOS, SOD-1 and -2, Bcl-2 and decreased relative gene expression of NF-κB, IL-17A, Bax, and caspases-3 and -9. Taken together, the data show that DATS can effectively mitigate MetS and have protective effects against ex vivo induced myocardial I/R injury in MetS rat.

Protective effects of valsartan administration on doxorubicin­induced myocardial injury in rats and the role of oxidative stress and NOX2/NOX4 signaling.

Clinical application of doxorubicin (DOX) is hampered by its potential cardiotoxicity, however angiotensin receptor blockers could attenuate DOX­induced cardiomyopathy. The present study tested the hypothesis that simultaneous administration of valsartan (Val) with DOX could prevent DOX­induced myocardial injury by modulating myocardial NAD(P)H oxidase (NOX) expression in rats. Eight­week­old male Sprague­Dawley rats were randomly divided into control (CON), DOX, and DOX+Val groups. After 10 weeks, surviving rats underwent echocardiography examination, myocardial mRNA and protein expression detection of NOX1, NOX2 and NOX4. H9C2 cells were used to perform in vitro experiments, reactive oxygen species (ROS) production and apoptosis were observed under the conditions of down­ or upregulation of NOX2 and NOX4 in DOX­ and DOX+Val­treated H9C2 cells. Cardiac function was significantly improved, pathological lesion and collagen volume fraction were significantly reduced in the DOX+Val group compared with the DOX group (all P<0.05). Myocardial protein and mRNA expression of NOX2 and NOX4 was significantly downregulated in DOX+Val group compared with in the DOX group (all P<0.05). In vitro, ROS production and apoptosis in DOX­treated H9C2 cells was significantly reduced by NOX2­small interfering (si)RNA and NOX4­siRNA, and significantly increased by overexpressing NOX2 and NOX4. To conclude, Val applied simultaneously with DOX could prevent DOX­induced myocardial injury and reduce oxidative stress by downregulating the myocardial expression of NOX2 and NOX4 in rats.

Resveratrol Inhibits Ischemia-Induced Myocardial Senescence Signals and NLRP3 Inflammasome Activation.

AIMS: The aim of this study was to investigate whether resveratrol (RSV) could ameliorate ischemia- and hypoxia-associated cardiomyocyte apoptosis and injury via inhibiting senescence signaling and inflammasome activation. MATERIALS AND METHODS: Mice were treated with RSV by gastric tube (320 mg/kg/day) or vehicle one week before left coronary artery ligation or sham surgery until the end of the experiments. After pressure-volume loop analysis, mouse hearts were harvested for histopathological (including PSR, TTC, TUNEL staining, immunohistochemistry, and immunofluorescence) and molecular analysis by western blotting and RT-PCR. In addition, neonatal rat cardiomyocytes (NRCMs), cardiac fibroblasts (CFs), and macrophages were isolated for in vitro experiments. Key Findings. RSV treatment decreased mortality and improved cardiac hemodynamics. RSV inhibited the expression of senescence markers (p53, p16, and p19), inflammasome markers (NLRP3 and Cas1 p20), and nuclear translocation of NF-κB, hence alleviating infarction area, fibrosis, and cell apoptosis. RSV also inhibited expression of interleukin- (IL-) 1ß, IL-6, tumor necrosis factor-α, and IL-18 in vivo. In in vitro experiment, RSV prevented hypoxia-induced NRCM senescence and apoptosis. After inhibition of sirtuin 1 (Sirt1) by EX27, RSV failed to inhibit p53 acetylation and expression. Moreover, RSV could inhibit expression of NLRP3 and caspase 1 p20 in NRCMs, CFs, and macrophages, respectively, in in vitro experiments. Significance. Our findings revealed that RSV protected against ischemia-induced mouse heart injury in vivo and hypoxia-induced NRCM injury in vitro via regulating Sirt1/p53-mediated cell senescence and inhibiting NLRP3-mediated inflammasome activation.

Hydrogen Sulfide Treatment Improves Post-Infarct Remodeling and Long-Term Cardiac Function in CSE Knockout and Wild-Type Mice.

Hydrogen sulfide (H2S) is recognized as an endogenous gaseous signaling molecule generated by cystathionine γ-lyase (CSE) in cardiovascular tissues. H2S up-regulation has been shown to reduce ischemic injury, and H2S donors are cardioprotective in rodent models when administered concurrent with myocardial ischemia. We evaluated the potential utility of H2S therapy in ameliorating cardiac remodeling with administration delayed until 2 h post-infarction in mice with or without cystathionine γ-lyase gene deletion (CSE-/-). The slow-release H2S donor, GYY4137, was administered from 2 h after surgery and daily for 28 days following myocardial infarction (MI) induced by coronary artery ligation, comparing responses in CSE-/- with wild-type (WT) mice (n = 5-10/group/genotype). Measures of cardiac function and expression of key genes associated with cardiac hypertrophy, fibrosis, and apoptosis were documented in atria, ventricle, and kidney tissues. Post-MI GYY4137 administration reduced infarct area and restored cardiac function, accompanied by reduction of the elevated ventricular expression of genes mediating cardiac remodeling to near-normal levels. Few differences between WT and CSE-/- mice were observed, except CSE-/- mice had higher blood pressures, and higher atrial Mir21a expression across all treatment groups. These findings suggest endogenous CSE gene deletion does not substantially exacerbate the long-term response to MI. Moreover, the H2S donor GYY4137 administered after onset of MI preserves cardiac function and protects against adverse cardiac remodeling in both WT and CSE-deficient mice.

Paeoniflorin Attenuates Myocardial Fibrosis in Isoprenaline-induced Chronic Heart Failure Rats via Inhibiting P38 MAPK Pathway.

Paeoniforin (Pae) is a monoterpenoid glycoside compound and has many biological activities, such as immunosuppression, anti-inflammation and anti-cell proliferation. However, the effects and mechanisms of Pae on chronic heart failure (CHF) remain unclear. This study was conducted to assess the effects and mechanisms of Pae on myocardial fbrosis in isoprenaline (Iso)-induced CHF rats. Pae (20 mg/kg) was intragastrically administrated to CHF rats for 6 weeks. Cardiac structure and function were assessed. The protein and mRNA levels of transforming growth factor ß1 (TGF-ß1) and p38 were detected. Compared to Iso group, Pae could alleviate myocardial fibrosis and improve cardiac function in CHF rats. The levels of collagen volume fraction (13.75%±3.77% vs. 30.97%±4.22%, P<0.001) and perivascular collagen volume area (14.32%±2.50% vs. 28.31%±3.16%, P<0.001) were signifcantly reduced in Pae group as compared with those in Iso group. The expression of TGF-ß1 protein (0.30±0.07 vs. 0.66±0.07, P<0.05) and mRNA (3.51±0.44 vs. 7.58±0.58, P<0.05) decreased signifcantly in Pae group as compared with that in Iso group. The expression of p38 protein (0.36±0.12 vs. 0.81±0.38, P<0.05) and mRNA (3.84±0.05 vs. 4.40±0.17, P<0.05) also decreased markedly in Pae group as compared with that in Iso group. Pae could attenuate myocardial fbrosis and improve cardiac function in CHF rats by down-regulating the p38 MAPK signaling pathway.

Innate Lymphoid Cells Play a Pathogenic Role in Pericarditis.

We find that cardiac group 2 innate lymphoid cells (ILC2s) are essential for the development of IL-33-induced eosinophilic pericarditis. We show a pathogenic role for ILC2s in cardiac inflammation, in which ILC2s activated by IL-33 drive the development of eosinophilic pericarditis in collaboration with cardiac fibroblasts. ILCs, not T and B cells, are required for the development of pericarditis. ILC2s transferred to the heart of Rag2-/-Il2rg-/- mice restore their susceptibility to eosinophil infiltration. Moreover, ILC2s direct cardiac fibroblasts to produce eotaxin-1. We also find that eosinophils reside in the mediastinal cavity and that eosinophils transferred to the mediastinal cavity of eosinophil-deficient ΔdblGATA1 mice following IL-33 treatment migrate to the heart. Thus, the serous cavities may serve as a reservoir of cardiac-infiltrating eosinophils. In humans, patients with pericarditis show higher amounts of ILCs in pericardial fluid than do healthy controls and patients with other cardiac diseases. We demonstrate that ILCs play a critical role in pericarditis.

Chinese herbal preparations for chronic heart failure: Study protocol for an umbrella review of systematic reviews and meta-analyses.

BACKGROUND: Chinese herbal preparations (CHPs) have been reported to be effective in the management of chronic heart failure (CHF); they are beneficial in improving cardiac function, reducing hospital stays and readmission. However, the credibility of their effectiveness evidence has not been evaluated. We aim to summarize and evaluate current effectiveness evidence of traditional Chinese medicine in the management of CHF. METHODS: We will search PubMed, Embase, the Cochrane Database of Systemic Review (CDSR), and Web of Science from inception to December 2019 for systematic reviews that assessing the effectiveness of CHPs for CHF. The search will be performed without language restriction. Experimental interventions will include any type of CHPs, and control interventions will include placebo, sham interventions, usual care, or no controls. The primary outcome will be the changes in heart function classification defined by the New York Heart Association. Secondary outcomes include left ventricular ejection fraction, Six Minute Walk Test, other efficacy outcomes, and adverse events. We will use I statistics to assess the between-study heterogeneity in each meta-analysis, Eager test to detect publication bias, and the ratio of observed versus expected number of trials with positive findings. We will summarize the evidence and classify them into convincing, highly suggestive, suggestive, or weak. RESULTS: The results of this study will be published in a peer-reviewed journal. ETHICS AND DISSEMINATION: No ethical approval and patient consent are required since this study data is based on published literature. The results of the study will be submitted to a peer-reviewed journal. PROTOCOL REGISTRATION NUMBER: PROSPERO CRD 42019139649 (https://www.crd.york.ac.uk/PROSPERO/#joinuppage).

Platelet-derived growth factor-AB improves scar mechanics and vascularity after myocardial infarction.

Therapies that target scar formation after myocardial infarction (MI) could prevent ensuing heart failure or death from ventricular arrhythmias. We have previously shown that recombinant human platelet-derived growth factor-AB (rhPDGF-AB) improves cardiac function in a rodent model of MI. To progress clinical translation, we evaluated rhPDGF-AB treatment in a clinically relevant porcine model of myocardial ischemia-reperfusion. Thirty-six pigs were randomized to sham procedure or balloon occlusion of the proximal left anterior descending coronary artery with 7-day intravenous infusion of rhPDGF-AB or vehicle. One month after MI, rhPDGF-AB improved survival by 40% compared with vehicle, and cardiac magnetic resonance imaging showed left ventricular (LV) ejection fraction improved by 11.5%, driven by reduced LV end-systolic volumes. Pressure volume loop analyses revealed improved myocardial contractility and energetics after rhPDGF-AB treatment with minimal effect on ventricular compliance. rhPDGF-AB enhanced angiogenesis and increased scar anisotropy (high fiber alignment) without affecting overall scar size or stiffness. rhPDGF-AB reduced inducible ventricular tachycardia by decreasing heterogeneity of the ventricular scar that provides a substrate for reentrant circuits. In summary, we demonstrated that rhPDGF-AB promotes post-MI cardiac wound repair by altering the mechanics of the infarct scar, resulting in robust cardiac functional improvement, decreased ventricular arrhythmias, and improved survival. Our findings suggest a strong translational potential for rhPDGF-AB as an adjunct to current MI treatment and possibly to modulate scar in other organs.

An epicardial delivery of nitroglycerine by active hydraulic ventricular support drug delivery system improves cardiac function in a rat model.

We have used a novel active hydraulic ventricular support drug delivery system (ASD) device, which is a non-transplant surgical approach, can adhere to heart surface, and deliver the drug directly into the epicardium. This study is intended to compare the effect of administration of nitroglycerine (NTG) through ASD and intravenous injection on the ischemic injury during acute myocardial infarction (AMI). 30 male SD rats were allocated into five groups (n = 6): sham, AMI, I.V., ASD high dose (ASDH), and ASD low dose (ASDL) respectively. Ligation of the left anterior descending (LAD) coronary artery was performed to induce myocardial infarction. Electrocardiograms were monitored, and serum myoglobin (Mb) was assessed. Hemodynamics was observed on pre- and post-operation. Hematoxylin and eosin (H&E) staining was performed for histological diagnosis. In all model animals, ligation of LAD provoked ST segment elevation and Mb level augmentation. In ASDH group, Mb showed obvious decrease as compared with other treatment groups. Hemodynamic parameters showed significant improvement in ASDH and ASDL groups than the I.V. group. H&E staining showed that AMI group rats had wavy fibers and loss of transverse striations while ASD group rats had obvious improvement. Unlike the I.V. group, ASD group rats showed significant vasodilation. Therefore, delivery of NTG through ASD to the cardiomyocytes could improve the therapeutic efficacy. A novel effective route for local delivery of agents to manage AMI has been proved.

Nortriptyline serum concentration as a predictor for cardiac risk in amitriptyline-treated patients.

PURPOSE: Tricyclic antidepressants have been shown to affect electrocardiogram (ECG) parameters, but there is limited evidence in relation to the serum concentrations. Therefore, we aimed to evaluate a prediction of cardiac risk in amitriptyline- and doxepin-treated patients by serum concentrations. PATIENTS AND METHODS: The association between serum concentrations of amitriptyline (n = 100) and doxepin (n = 71) and ECG parameters was retrospectively examined using linear regression analysis. Mann-Whitney U tests were applied to evaluate differences in QTc intervals in patients with serum concentrations above and below the upper limit of the therapeutic reference range, as well as the alert level of each target drug. RESULTS: The sum serum concentration of amitriptyline and the nortriptyline serum concentration were significantly associated with an increased PQ interval (p = 0.020, p = 0.007), as well as with increased QTcB (p = 0.012, p < 0.001) and QTcF intervals (p = 0.025, p < 0.001). The nortriptyline concentration was significantly associated with the QRS interval (p = 0.003). In patients with active moiety concentrations above the alert level (300 ng/ml) and nortriptyline concentrations above the reference range (170 ng/ml), the QTcB interval was significantly prolonged (p = 0.032, p = 0.007). No significant association with any ECG parameter was detected for doxepin serum concentrations. CONCLUSION: The effect of amitriptyline on ECG parameters may be explained by nortriptyline alone. Accordingly, with increasing nortriptyline concentrations, the potential risk for an atrioventricular block, a bundle branch block, and prolongation of QTc interval may increase significantly.

LongShengZhi capsule inhibits doxorubicin-induced heart failure by anti-oxidative stress.

Heart failure is a major cause of morbidity and mortality worldwide. LongShengZhi capsule (LSZ), a traditional Chinese medicine, is used for treatment of patients with vascular diseases. Herein we investigated the effect of LSZ treatment on doxorubicin (DOX)-induced heart failure in mice. C57BL/6 mice randomly in 3 groups received following treatment: Control group, mice were fed normal chow; DOX group, mice were intraperitoneally injected DOX to induce heart failure and fed normal chow; and LSZ group, mice were injected DOX and fed normal chow containing LSZ. DOX induced heart failure as evidenced by increased serum creatine kinase, lactic dehydrogenase and α-hydroxybutyrate dehydrogenase, and cardiac fibrosis. However, LSZ treatment substantially inhibited DOX-induced heart failure parameters. Mechanistically, LSZ reduced collagen content and fibrosis by inhibiting expression of collagen type I α1 (COL1α1), COL1α2, α-smooth muscle actin and transforming growth factor ß1. In addition, DOX-induced cell apoptosis was inhibited by LSZ, coupled with reduced caspase 3 activity and mRNA expression. LSZ decreased inflammatory cytokine levels. More importantly, LSZ decreased oxidative stress by inducing expression of anti-oxidative stress enzymes including superoxide dismutase 1 (SOD1), SOD2, catalase and glutathione peroxidase 1 through activation of forkhead box O3A and sirtuin 3. In conclusion, our study demonstrates that LSZ reduces heart failure by reducing production of reactive oxygen species and inhibiting inflammation/apoptosis. Our study also suggests the potential application of LSZ for heart failure treatment.

Three-dimensional integrated quantitative modeling and fluorescent imaging of doxorubicin-induced cardiotoxicity in a whole organ using a deconvolution microscope.

The quantification and visualization of fluorescent staining at the whole organ level remain a challenge. Deconvolution image systems allow multi-dimensional imaging and stereo-measurement via rapid 3D reconstruction. To demonstrate this technique, we investigated doxorubicin-induced cardiotoxicity in zebrafish. Fluorogenic probe and immunofluorescence were employed to identify cardiac reactive oxygen species generation and myocardial apoptosis, respectively. We revealed the spatial distribution of fluorescent staining across the whole heart by this approach. In addition, the fluorescence intensities and fluorescence-dyed volumes in the zebrafish heart were quantified automatically. Importantly, doxorubicin treatment induced more ROS generation in the ventricle as compared to the atrium, while the levels of activated caspase-3 were much higher in the atrioventricular junction. These results would have been difficult to observe using traditional 2D images. Therefore, our deconvolution imaging strategy allows the 3D quantification and visualization of fluorescent staining at the whole organ level, and will thus support in vivo studies.

Effects of the combination of tanshinone IIA and puerarin on cardiac function and inflammatory response in myocardial ischemia mice.

BACKGROUND: Ventricular remodeling is a major pathological process of normal heart failure. With the aging of society, poor diet control, social, psychological and other risk factors in our country, the incidence of myocardial infarction and hypertension is reported to increase yearly. Many treatment methods have effectively delayed the occurrence of ventricular remodeling. However, in order to prevent and delay the occurrence and development of ventricular remodeling, the new treatment strategy cannot be ignored. METHODS: In this study, we used male C57BL/6 mice (8 weeks old), weight 23 g-27 g, SPF grade. According to the established methods of the research group, the left anterior descending branch of the coronary artery (LAD) was used to make the model of myocardial ischemia, and which was evaluated by the change of EF value in mice. The experiment included seven groups: sham operation group, model group, metoprolol group, puerarin group, tanshinone IIA group, tanshinone IIA: puerarin =1:1 group, tanshinone IIA: puerarin =1:2 group. The changes of cardiac function in each group were observed by echocardiography and hemodynamics after the drug delivery cycle was 3d, 7d, 14d and 28d. Detection of 3d serum enzyme indexes LDH, CK and CK-MB by automatic biochemical analyzer. The expression of CD11b, F4/80, Ly6C in cardiac tissues were detected by flow cytometry at 3d and 7d. The expression of IL-1ß and TNF- α in serum were detected by ELISA. IL-1ß, IL-6, IL-10, iNOS and other related genes were detected by RT-PCR method. HE, Masson staining and immunohistochemical staining were used to observe the changes of myocardial histomorphology in mice. We also examined the effects of different drug treatments on the proliferation and function of Raw264.7 cells, H9C2 cells and HUVECs. Western blot examined the effects of different drug treatments on the expression of inflammatory pathway related proteins TLR4 and C/EBP-ß. RESULTS: 1. Echocardiographic results showed that with the prolongation of ischemic time, the ejection fraction of the model group, the shortening rate of the short axis of the left ventricle, the flow rate of the outflow tract were significantly decreased, and the structure of the ventricle was significantly changed. Hemodynamic tests showed that the maximum and maximum rate of decline in the post-ischemia model group were significantly reduced, with increased systolic and diastolic volume, and a decrease in pressure difference. After treatment with drugs, all groups improved, but tanshinone IIA: puerarin = 1:1 group can significantly improve the above indicators after 28d of administration, which can effectively relieve the deterioration of cardiac function caused by acute myocardial infarction. 2. After administration for 3 and 7 days, the inflammatory cell CD11b monocytes and the F4/80 phenotype macrophages in heart tissue were detected by flow cytometry, and it was found that tanshinone IIA: puerarin = 1:1 can inhibit the release of inflammatory cells. The results of RT-PCR showed that the tanshinone IIA: puerarin = 1:1 group significantly improved the expression of inflammatory cytokines such as IL-1ß, IL-6, IL-10, and iNOS. In the immunohistochemical analysis of iNOS and Arg-1, the tanshinone IIA and puerarin 1:1 treatment group was able to inhibit the expression of M1 macrophages in the early stage of inflammation and promote the expression of M2 macrophages. 3. The cardiac index increased significantly and the serum TGF-ß increased after 28d. The combination of tanshinone IIA and puerarin could significantly reduce these indexes. HE, Masson, Sirius red and immunohistochemical staining were found in the combination of tanshinone IIA and puerarin can significantly reduce the structure of acute ischemic myocardial cell damage and interstitial edema, reduce collagen synthesis, and fibroblasts release, thereby inhibiting myocardial fibrosis and heart remodeling. 4. MTT assay showed a significantly greater proliferation of above two cells types treated with tanshinone IIA: puerarin =1:1 and more nodes and meshes were found in tanshinone IIA: puerarin =1:1 group compared with other groups. 5. The combination of tanshinone IIA and puerarin could regulate inflammation through inhibiting the expression of TLR4 protein, but up-regulating the expression of C/EBP-ß protein. CONCLUSION: The combination of tanshinone IIA and puerarin inhibits the immersion of inflammatory cells. Improving hemodynamics by improving cardiac function, reducing the destruction of cardiac myocytes, reducing collagen synthesis, inhibiting myocardial fibrosis and ventricular remodeling. Through the whole experiment, tanshinone IIA: puerarin = 1:1 is the best.

Effect of Empagliflozin on Cardiac Function, Adiposity, and Diffuse Fibrosis in Patients with Type 2 Diabetes Mellitus.

Empagliflozin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor, significantly improves cardiovascular outcomes in diabetic patients; however, the mechanism is unclear. We hypothesized that empagliflozin might have beneficial effects on cardiac function, structure, adiposity, and myocardial diffuse fibrosis. This prospective study enrolled 35 patients (48.6% men, age 63.5 ± 9.7 years) with type 2 diabetes mellitus (T2DM) from June 1, 2017, to November 31, 2018. The patients received an SGLT2 inhibitor (empagliflozin 25 or 12.5 mg/d) for 6 months in addition to stable oral hypoglycaemic treatment. All patients underwent cardiac magnetic resonance imaging (CMRI) before and after empagliflozin treatment. Left ventricular (LV) function and structure were quantified using cine CMRI. Cardiac adiposity was defined based on pericardial fat and intracardiac triglyceride contents, whereas myocardial diffuse fibrosis was indicated by extracellular volume (ECV). The statistical significance of parameter changes was assessed using paired t-test and stepwise multiple linear regression. There were no significant differences in LV function and structure changes. Cardiac adiposity and diffuse fibrosis indices were also not different before and after empagliflozin treatment. Concerning clinical parameters, only a significant decrease in systolic blood pressure (by 6.4 mmHg) was observed (p = 0.013). Stepwise multiple linear regression revealed that worse baseline MRI parameters were associated with better improvements. Intracardiac triglyceride content decrease was inversely associated with baseline intracardiac triglyceride content (p < 0.001). Pericardial fat changes were negatively correlated with baseline pericardial fat (p < 0.001) and ECV changes (p = 0.028). ECV changes were inversely associated with baseline ECV (p < 0.001), baseline LV ejection fraction (p < 0.001), and LV mass index changes (p = 0.020). This study demonstrated that 6 months of empagliflozin treatment did not significantly improve the LV function, structure, adiposity, and diffuse fibrosis in patients with T2DM. Further, the beneficial effects of empagliflozin treatment might be more evident in patients with worse baseline LV substrate and structure.