Mechanism of Qili Qiangxin Capsule for Heart Failure Based on miR133a-Endoplasmic Reticulum Stress.

OBJECTIVE: To investigate the pharmacological mechanism of Qili Qiangxin Capsule (QLQX) improvement of heart failure (HF) based on miR133a-endoplasmic reticulum stress (ERS) pathway. METHODS: A left coronary artery ligation-induced HF after myocardial infarction model was used in this study. Rats were randomly assigned to the sham group, the model group, the QLQX group [0.32 g/(kg·d)], and the captopril group [2.25 mg/(kg·d)], 15 rats per group, followed by 4 weeks of medication. Cardiac function such as left ventricular ejection fraction (EF), fractional shortening (FS), left ventricular systolic pressure (LVSP), left ventricular end diastolic pressure (LVEDP), the maximal rate of increase of left ventricular pressure (+dp/dt max), and the maximal rate of decrease of left ventricular pressure (-dp/dt max) were monitored by echocardiography and hemodynamics. Hematoxylin and eosin (HE) and Masson stainings were used to visualize pathological changes in myocardial tissue. The mRNA expression of miR133a, glucose-regulated protein78 (GRP78), inositol-requiring enzyme 1 (IRE1), activating transcription factor 6 (ATF6), X-box binding protein1 (XBP1), C/EBP homologous protein (CHOP) and Caspase 12 were detected by RT-PCR. The protein expression of GRP78, p-IRE1/IRE1 ratio, cleaved-ATF6, XBP1-s (the spliced form of XBP1), CHOP and Caspase 12 were detected by Western blot. TdT-mediated dUTP nick-end labeling (TUNEL) staining was used to detect the rate of apoptosis. RESULTS: QLQX significantly improved cardiac function as evidenced by increased EF, FS, LVSP, +dp/dt max, -dp/dt max, and decreased LVEDP (P<0.05, P<0.01). HE staining showed that QLQX ameliorated cardiac pathologic damage to some extent. Masson staining indicated that QLQX significantly reduced collagen volume fraction in myocardial tissue (P<0.01). Results from RT-PCR and Western blot showed that QLQX significantly increased the expression of miR133a and inhibited the mRNA expressions of GRP78, IRE1, ATF6 and XBP1, as well as decreased the protein expressions of GRP78, cleaved-ATF6 and XBP1-s and decreased p-IRE1/IRE1 ratio (P<0.05, P<0.01). Further studies showed that QLQX significantly reduced the expression of CHOP and Caspase12, resulting in a significant reduction in apoptosis rate (P<0.05, P<0.01). CONCLUSION: The pharmacological mechanism of QLQX in improving HF is partly attributed to its regulatory effect on the miR133a-IRE1/XBP1 pathway.

Multisize Electrode Field-of-View: Validation by High Resolution Gadolinium-Enhanced Cardiac Magnetic Resonance.

BACKGROUND: Voltage mapping to detect ventricular scar is important for guiding catheter ablation, but the field-of-view of unipolar, bipolar, conventional, and microelectrodes as it relates to the extent of viable myocardium (VM) is not well defined. OBJECTIVES: The purpose of this study was to evaluate electroanatomic voltage-mapping (EAVM) with different-size electrodes for identifying VM, validated against high-resolution ex-vivo cardiac magnetic resonance (HR-LGE-CMR). METHODS: A total of 9 swine with early-reperfusion myocardial infarction were mapped with the QDOT microcatheter. HR-LGE-CMR (0.3-mm slices) were merged with EAVM. At each EAVM point, the underlying VM in multisize transmural cylinders and spheres was quantified from ex vivo CMR and related to unipolar and bipolar voltages recorded from conventional and microelectrodes. RESULTS: In each swine, 220 mapping points (Q1, Q3: 216, 260 mapping points) were collected. Infarcts were heterogeneous and nontransmural. Unipolar and bipolar voltage increased with VM volumes from >175 mm3 up to >525 mm3 (equivalent to a 5-mm radius cylinder with height >6.69 mm). VM volumes in subendocardial cylinders with 1- or 3-mm depth correlated poorly with all voltages. Unipolar voltages recorded with conventional and microelectrodes were similar (difference 0.17 ± 2.66 mV) and correlated best to VM within a sphere of radius 10 and 8 mm, respectively. Distance-weighting did not improve the correlation. CONCLUSIONS: Voltage increases with transmural volume of VM but correlates poorly with small amounts of VM, which limits EAVM in defining heterogeneous scar. Microelectrodes cannot distinguish thin from thick areas of subendocardial VM. The field-of-view for unipolar recordings for microelectrodes and conventional electrodes appears to be 8 to 10 mm, respectively, and unexpectedly similar.

Heterogeneous repolarization creates ventricular tachycardia circuits in healed myocardial infarction scar.

Arrhythmias originating in scarred ventricular myocardium are a major cause of death, but the underlying mechanism allowing these rhythms to exist remains unknown. This gap in knowledge critically limits identification of at-risk patients and treatment once arrhythmias become manifest. Here we show that potassium voltage-gated channel subfamily E regulatory subunits 3 and 4 (KCNE3, KCNE4) are uniquely upregulated at arrhythmia sites within scarred myocardium. Ventricular arrhythmias occur in areas with a distinctive cardiomyocyte repolarization pattern, where myocyte tracts with short repolarization times connect to myocytes tracts with long repolarization times. We found this unique pattern of repolarization heterogeneity only in ventricular arrhythmia circuits. In contrast, conduction abnormalities were ubiquitous within scar. These repolarization heterogeneities are consistent with known functional effects of KCNE3 and KCNE4 on the slow delayed-rectifier potassium current. We observed repolarization heterogeneity using conventional cardiac electrophysiologic techniques that could potentially translate to identification of at-risk patients. The neutralization of the repolarization heterogeneities could represent a potential strategy for the elimination of ventricular arrhythmia circuits.

Quantification of murine myocardial infarct size using 2-D and 4-D high-frequency ultrasound.

Ischemic heart disease is the leading cause of death in the United States, Canada, and worldwide. Severe disease is characterized by coronary artery occlusion, loss of blood flow to the myocardium, and necrosis of tissue, with subsequent remodeling of the heart wall, including fibrotic scarring. The current study aims to demonstrate the efficacy of quantitating infarct size via two-dimensional (2-D) echocardiographic akinetic length and four-dimensional (4-D) echocardiographic infarct volume and surface area as in vivo analysis techniques. We further describe and evaluate a new surface area strain analysis technique for estimating myocardial infarction (MI) size after ischemic injury. Experimental MI was induced in mice via left coronary artery ligation. Ejection fraction and infarct size were measured through 2-D and 4-D echocardiography. Infarct size established via histology was compared with ultrasound-based metrics via linear regression analysis. Two-dimensional echocardiographic akinetic length (r = 0.76, P = 0.03), 4-D echocardiographic infarct volume (r = 0.85, P = 0.008), and surface area (r = 0.90, P = 0.002) correlate well with histology. Although both 2-D and 4-D echocardiography were reliable measurement techniques to assess infarct, 4-D analysis is superior in assessing asymmetry of the left ventricle and the infarct. Strain analysis performed on 4-D data also provides additional infarct sizing techniques, which correlate with histology (surface strain: r = 0.94, P < 0.001, transmural thickness: r = 0.76, P = 0.001). Two-dimensional echocardiographic akinetic length, 4-D echocardiography ultrasound, and strain provide effective in vivo methods for measuring fibrotic scarring after MI.NEW & NOTEWORTHY Our study supports that both 2-D and 4-D echocardiographic analysis techniques are reliable in quantifying infarct size though 4-D ultrasound provides a more holistic image of LV function and structure, especially after myocardial infarction. Furthermore, 4-D strain analysis correctly identifies infarct size and regional LV dysfunction after MI. Therefore, these techniques can improve functional insight into the impact of pharmacological interventions on the pathophysiology of cardiac disease.

Structure and function of the ventricular tachycardia isthmus.

Catheter ablation of postinfarction reentrant ventricular tachycardia (VT) has received renewed interest owing to the increased availability of high-resolution electroanatomic mapping systems that can describe the VT circuits in greater detail, and the emergence and need to target noninvasive external beam radioablation. These recent advancements provide optimism for improving the clinical outcome of VT ablation in patients with postinfarction and potentially other scar-related VTs. The combination of analyses gleaned from studies in swine and canine models of postinfarction reentrant VT, and in human studies, suggests the existence of common electroanatomic properties for reentrant VT circuits. Characterizing these properties may be useful for increasing the specificity of substrate mapping techniques and for noninvasive identification to guide ablation. Herein, we describe properties of reentrant VT circuits that may assist in elucidating the mechanisms of onset and maintenance, as well as a means to localize and delineate optimal catheter ablation targets.

Xuesaitong injection treating acute myocardial infarction: A systematic review and meta-analysis.

BACKGROUND: Although the incidence of acute myocardial infarction (AMI) is decreasing, the mortality in AMI patients remains substantial. Traditional Chinese medicine has shown its role in the prevention and management of AMI. The purpose of this study is to evaluate the clinical efficacy of Xuesaitong injection (XST) for the treatment of AMI by a meta-analysis. METHODS: A literature search was performed in 5 medical databases up to June 1, 2020. Randomized controlled trials involving XST combined with conventional treatment versus conventional treatment were included. A meta-analysis of clinical efficacy, left ventricular function and other objective parameters was performed to evaluate the effects of XST on AMI. RESULTS: Five randomized controlled trials involving 539 participants were eventually included. Meta-analysis showed that the combination of XST and conventional treatment could achieve significantly better effect on improving clinical efficacy (risk ratio: 1.09 [1.01, 1.17]; P = .04), left ventricular ejection fraction (mean difference [MD]: 3.18 [1.69, 4.67]; P < .0001), hypersensitive C-reactive protein (MD: -2.58 [-5.04, -0.12]; P = .04), interleukin 6 (MD: -26.00 [-38.85, -13.16]; P < .0001), cardiac troponin T (MD: -15.85 [-18.09, -13.61]; P < .00001) and creatine kinase myocardial isoenzyme (MD: -73.06 [-79.74, -66.37]; P < .00001). CONCLUSION: XST combined with conventional treatment can achieve better efficacy on clinical performance and some of the AMI related parameters. However the interpretation of the results should be cautious, due to the relatively low quality of included trials. More rigorously designed, large-scaled, randomized controlled trials are warranted to support its clinical use in the future.

Psycho-cardiology therapeutic effects of Shuangxinfang in rats with depression-behavior post acute myocardial infarction: Focus on protein S100A9 from proteomics.

BACKGROUND: Depressive disorders induced by acute myocardial infarction (AMI) play a pivotal role in the deterioration of cardiac function, and Shuangxinfang (Psycho-cardiology Formula, PCF) was reported to alleviate heart function damage and improve depression-like behavior, but the complex mechanism in such process has not been clarified. METHODS: AMI models were established and PCF was administered in rats. Subjects were then assessed in open field test (OFT) and forced swimming test (FST) recapitulating symptoms of depressive disorder. Afterward, pharmacoproteomic profiling of the hippocampus and peri-infarct border zone (BZ) was performed using a label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS) technique, to identify contributing proteins and pathways responsible for myocardial ischemia and behavioral allostasis. Bioinformatics analysis was processed for further investigation, while western blotting was employed for testing dominating proteins to validate proteomic results. RESULTS: Rats in the AMI group showed depression-like behavior in OFT and FST, which was improved by PCF. There were 131 differentially expressed proteins (DEPs) in BZ and 64 proteins in the hippocampus being detected and quantified shared by the sham group, the AMI group, and the PCF group. Subsequently, pertinent pathways and molecular functions were further identified. Altered molecules were discovered to be enriched in the apoptotic process, innate immune response, and NF-κB transcription factor activity in BZ, as well as chemical synaptic transmission, axon, collagen binding, cell adhesion, response to carbohydrate, laminin binding, and cellular response to nitric oxide in the hippocampus. Groups of signal transducers were also able to select multiple pathways, including innate immunity and arginine biosynthesis in the heart, also integrin signaling in the brain. DEPs were intersected from the myocardium and hippocampus to screen out the protein S100A9, which was up-regulated in the AMI group compared with the sham, and showed a down-regulation trend after treatment with PCF. CONCLUSION: Taken together, we present a comprehensive proteomics analysis of rat models with depression post-AMI. Reviewing the literatures concerned, it's hypothesized that macrophage/microglia inflammation mediated by S100A9 might be the pivotal pathogenic process of psycho-cardiology disease, as well as potential mechanisms for the treatment of PCF.

Postinfarct ventricular tachycardia substrate: Characterization and ablation of conduction channels using ripple mapping.

BACKGROUND: Conduction channels have been demonstrated within the postinfarct scar and seem to be co-located with the isthmus of ventricular tachycardia (VT). Mapping the local scar potentials (SPs) that define the conduction channels is often hindered by large far-field electrograms generated by healthy myocardium. OBJECTIVE: The purpose of this study was to map conduction channel using ripple mapping to categorize SPs temporally and anatomically. We tested the hypothesis that ablation of early SPs would eliminate the latest SPs without direct ablation. METHODS: Ripple maps of postinfarct scar were collected using the PentaRay (Biosense Webster) during normal rhythm. Maps were reviewed in reverse, and clusters of SPs were color-coded on the geometry, by timing, into early, intermediate, late, and terminal. Ablation was delivered sequentially from clusters of early SPs, checking for loss of terminal SPs as the endpoint. RESULTS: The protocol was performed in 11 patients. Mean mapping time was 65 ± 23 minutes, and a mean 3050 ± 1839 points was collected. SP timing ranged from 98.1 ± 60.5 ms to 214.8 ± 89.8 ms post QRS peak. Earliest SPs were present at the border, occupying 16.4% of scar, whereas latest SPs occupied 4.8% at the opposing border or core. Analysis took 15 ± 10 minutes to locate channels and identify ablation targets. It was possible to eliminate latest SPs in all patients without direct ablation (mean ablation time 16.3 ± 11.1 minutes). No VT recurrence was recorded (mean follow-up 10.1 ± 7.4 months). CONCLUSION: Conduction channels can be located using ripple mapping to analyze SPs. Ablation at channel entrances can eliminate the latest SPs and is associated with good medium-term results.

A Robust Percutaneous Myocardial Infarction Model in Pigs and Its Effect on Left Ventricular Function.

In this study, we created a reproducible myocardial infarction (MI) model in pigs characterized by a low mortality rate and significant changes in left ventricular function. After administering an arrhythmia prevention regimen, we created a 90-min balloon-induced percutaneous MI in 42 pigs below the first diagonal branch (D1) of the left anterior descending artery. Echocardiograms were performed before and 14 days after MI induction. Pigs with a > 30% decrease in left ventricular ejection fraction (LVEF) underwent electrophysiological mapping by the NOGA system. Our mortality rate was 4.8%. The incidence of ventricular fibrillation (VF) was 28.6%; all VF events were successfully resuscitated. At day 14, echocardiography and NOGA mapping confirmed transmural scar. LVEF decreased 41% from baseline. Radial and circumferential strain significantly decreased in the LAD distal to D1, and the LV showed dyssynchrony. An anti-arrhythmia regimen decreased mortality significantly, and our model induced dramatic functional changes. The basic procedures of the model included an arrhythmia prevention protocol and myocardial infarction creation, which effectively decreased mortality and provided a robust change in left ventricular (LV) function after 14 days.

Plasma fatty acids and kidney function decline in post-myocardial infarction patients of the Alpha Omega Cohort.

BACKGROUND AND AIMS: Age-related kidney function decline is accelerated in patients with coronary heart disease (CHD). CHD and chronic kidney disease may share common etiologies. We examined plasma fatty acids (FAs) as novel biomarkers of kidney function decline after myocardial infarction (MI). METHODS AND RESULTS: The analysis included 2329 Dutch post-MI patients aged 60-80y (Alpha Omega Cohort) most receiving state-of-the-art medications. Plasma FAs (% total FAs) in cholesteryl esters were assessed at baseline (2002-2006), and ∼40 months change in creatinine-cystatin C based glomerular filtration rate was estimated (eGFR, in ml/min per 1.73 m2). Beta coefficients for annual eGFR change in relation to plasma linoleic acid (LA; 50.1% of total FAs in CE), omega-3 FAs (EPA + DHA; 1.7%), odd-chain FAs (C15:0 and C17:0; 0.2%), and C14:0 (0.7%) were obtained from linear regression analyses adjusted for age, sex, smoking, and alcohol intake. Mean baseline eGFR ±SD was 78.5 ± 18.7, which declined by 4.7 ± 13.1 during follow-up, or 1.4 ± 3.9 per year. The annual decline in eGFR was less in patients with higher plasma LA (adjusted beta: 0.40 for LA >47 vs ≤ 47%, 95% CI: 0.01; 0.78; p = 0.046). Associations of plasma LA with annual eGFR decline were stronger in 437 patients with diabetes (1.21, 0.24; 2.19) and in 402 patients with CKD (eGFR<60; 0.90, -0.09; 1.89). Weaker, non-significant associations with kidney function decline were observed for the other plasma FAs. CONCLUSION: Higher plasma LA may be a good predictor of less kidney function decline after MI, particularly in patients with diabetes. The Alpha Omega Cohort is registered with clinicaltrials.gov, NCT03192410.

Integrating network pharmacology and experimental evidence to decipher the cardioprotective mechanism of Yiqihuoxue decoction in rats after myocardial infarction.

ETHNOPHARMACOLOGICAL RELEVANCE: "Qi deficiency and blood stasis" syndrome is one of the most common syndromes treated with Traditional Chinese Medicine among ischemic heart disease (IHD) patients in clinic. As a Chinese herbal formula with the function of tonifying Qi and activating blood, Yiqihuoxue Decoction (YQHX) has been frequently proven to be effective in the clinical treatment of IHD. AIM OF THE STUDY: The cardioprotective mechanisms of YQHX in treating ischemic heart disease were investigated, with emphasis on the key targets and pathways. MATERIALS AND METHODS: In the present study, the potential targets of compounds identified in YQHX were predicted using PharmMapper, Symmap, and STITCH databases, and a "herb-compound-target" network was constructed using Cytoscape. Subsequently, the GO and KEGG functional enrichment analyses were analyzed using the DAVID database. Furthermore, a protein-protein interaction network was constructed using STRING to obtain the key target information. Besides, we used a myocardial ischemia rat model to investigate the cardioprotective effects of YQHX. Transmission electron microscopy and Western blotting were used to observe apoptotic bodies and confirm protein expressions of key candidate targets, respectively. RESULTS: Network pharmacology showed that a total of 141 potential targets were obtained from these databases. The functional analysis results revealed that the targets of YQHX were largely associated with apoptosis, and the PI3K-AKT and MAPK pathways might represent key functional pathways. The hub genes of network include ALB, TP53, AKT1, TNF, VEGFA, EGFR, MAPK1, CASP3, JUN, FN1, MMP9, and MAPK8. In vivo, YQHX significantly improved cardiac function and suppressed apoptosis in ischemic rat myocardium. Furthermore, YQHX could significantly upregulate Nrf2 and HO-1 expression, and inhibit JNK phosphorylation. CONCLUSIONS: Based on network pharmacology and experimental evidence, this study proves that the cardioprotective effects and mechanisms of YQHX depend on multi-component, multi-target, and multi-pathway. In particular, YQHX exerts anti-apoptotic effects potentially by regulating the Nrf2/HO-1 and JNK-MAPK pathways.

Effect of Guanxin V in animal model of acute myocardial infarction.

BACKGROUND: Acute myocardial infarction (AMI) is the most serious and lethal manifestation of coronary heart disease worldwide, presenting extremely high disability and mortality. Our previous studies have shown that Guanxin V (GXV) could significantly improve the cardiac function and the blood flow dynamics, and reduce serum levels of inflammatory factors in AMI rats, thus triggering ventricular remodeling (VR) at post-AMI. METHODS: An in vivo AMI model was established in Syrian hamsters by performing the ligation of the left anterior descending coronary artery. Syrian hamsters were randomly divided into four groups, namely Sham operation group (n = 12), AMI group (n = 12), GXV group (GXV 6 g/Kg/d, n = 12), and Tranilast group (Tra 105 mg/Kg/d, n = 12). Drug intervention was conducted for consecutive 8 weeks. Relative biological indicators were measured in the 4th and 8th week, respectively. RESULTS: Cardiac functions were improved, and the infarcted size and heart weight index were limited in Syrian hamsters of GXV and Tra groups compared with those in AMI group. Furthermore, GXV was able to decrease the number of mast cells and chymase level in Syrian hamsters with AMI. Administration of GXV remarkably inactivated the renin-angiotension-aldosterone system, and alleviated myocardial fibrosis and cardiomyocyte apoptosis, thus slowing down VR at post-AMI. CONCLUSION: GXV slows down the process of VR at post-AMI by reducing chymase level and mast cells number, as well as inactivating the reninangiotension-aldosterone system..

The miRNA199a/SIRT1/P300/Yy1/sST2 signaling axis regulates adverse cardiac remodeling following MI.

Left ventricular remodeling following myocardial infarction (MI) is related to adverse outcome. It has been shown that an up-regulation of plasma soluble ST2 (sST2) levels are associated with lower pre-discharge left ventricular (LV) ejection fraction, adverse cardiovascular outcomes and mortality outcome after MI. The mechanisms involved in its modulation are unknown and there is not specific treatment capable of lowering plasma sST2 levels in acute-stage HF. We recently identified Yin-yang 1 (Yy1) as a transcription factor related to circulating soluble ST2 isoform (sST2) expression in infarcted myocardium. However, the underlying mechanisms involved in this process have not been thoroughly elucidated. This study aimed to evaluate the pathophysiological implication of miR-199a-5p in cardiac remodeling and the expression of the soluble ST2 isoform. Myocardial infarction (MI) was induced by permanent ligation of the left anterior coronary artery in C57BL6/J mice that randomly received antimiR199a therapy, antimiR-Ctrl or saline. A model of biomechanical stretching was also used to characterize the underlying mechanisms involved in the activation of Yy1/sST2 axis. Our results show that the significant upregulation of miR-199a-5p after myocardial infarction increases pathological cardiac hypertrophy by upregulating circulating soluble sST2 levels. AntimiR199a therapy up-regulates Sirt1 and inactivates the co-activator P300 protein, thus leading to Yy1 inhibition which decreases both expression and release of circulating sST2 by cardiomyocytes after myocardial infarction. Pharmacological inhibition of miR-199a rescues cardiac hypertrophy and heart failure in mice, offering a potential therapeutic approach for cardiac failure.

Sodium Tanshinone IIA sulfonate for acute myocardial infarction: a systematic review and Meta-analysis.

OBJECTIVE: To investigate the efficacy and safety of Sodium tanshinone ⅡA sulfonate (STS) plus the conventional treatment on acute myocardial infarction (AMI) patients. METHODS: We searched several electrical databases and hand searched several Chinese medical journals up to January 2019. Randomized controlled trials (RCTs) comparing STS plus conventional treatment with conventional treatment were retrieved. Study screening, data extraction, quality assessment, and data analysis were conducted in accordance with the Cochrane standards. RESULTS: Sixteen trials involving 1383 people were included. The Meta-analysis showed STS combined with conventional treatment was a better treatment option than conventional treatment alone in reducing the risk of mortality, heart failure, arrhythmia and shock. In addition, STS was associated with improvement in left ventricular ejection fraction (LVEF) and left ventricular end diastolic dimension (LVEDD). No significant difference of STS was found on recurrent angina and recurrent AMI. However, the safety of STS remained uncertain for limite data. CONCLUSION: Compared with conventional treatment alone, STS combined with conventional treatment may provide more benefits for patients with AMI. Due to the fact that the overall quality of all included trials is generally low, further large-scale high quality trials are warranted.

Chinese medicine GeGen-DanShen extract protects from myocardial ischemic injury through promoting angiogenesis via up-regulation of VEGF/VEGFR2 signaling pathway.

HEADINGS ETHNOPHARMACOLOGICAL RELEVANCE: Coronary heart disease (CHD) usually refers to myocardial ischemia or myocardial necrosis caused by coronary artery stenosis. GeGen and DanShen (GD) are popular Chinese herbs for the treatment of angina pectoris and myocardial infarction (MI). This sentence needs to be a separate paragraph. AIM OF THE STUDY: This study was to investigate the role of GD extract in promoting ischemic myocardial angiogenesis, and to explore its signaling mechanism, so as to provide a more reliable scientific basis for the clinical treatment of ischemic cardiovascular disease. MATERIALS AND METHODS: GD extract was initially analyzed by HPLC-Q-TOF MS. In vitro, migration assay and tube formation assay were subsequently used to detect the angiogenesis activity of GD extract in human umbilical vein endothelial cells (HUVECs). Following the in vitro study, an MI rat model was established by ligating the left anterior descending coronary artery (LAD), immediately followed by a 4-week daily GD extract treatment by intragastric administration. After the animal sacrifice, hematoxylin-eosin (HE) staining was conducted to observe the pathological changes of the infarct margin. Besides, the MI area was measured by 2,3,5-triphenyltetrazoliumchloride (TTC) staining. The microvascular density (MVD) was also quantified through CD31 immunohistochemistry. Moreover, the levels of VEGF, TXB2 and 6-keto-PGF1α in serum were detected by enzyme-linked immunosorbent assay. The expression of VEGFR2 and ERK were detected by immunohistochemistry as well. RESULTS: In vitro study, GD extract was found to induce significant angiogenesis in HUVECs. In vivo, smaller infarct size was found in treatment groups than that of the model group, and the protein expression of VEGFR2 as well as ERK in the marginal zone of MI in treatment groups were significantly increased. The morphological changes of myocardium were observed with a significant growth in the number of new blood vessels. Regarding the effect of GD extract, the serum levels of CK, LDH and TXB2 were consequently reduced, whereas the levels of VEGF, 6-keto-PGF1α were significantly increased. CONCLUSIONS: Based on the findings of this study, GD extract had a protective effect against MI in rats. The possible mechanism is to promote angiogenesis by regulating the VEGF/VEGFR2 signaling pathway after MI occurrence.

Ketone Ester Treatment Improves Cardiac Function and Reduces Pathologic Remodeling in Preclinical Models of Heart Failure.

BACKGROUND: Accumulating evidence suggests that the failing heart reprograms fuel metabolism toward increased utilization of ketone bodies and that increasing cardiac ketone delivery ameliorates cardiac dysfunction. As an initial step toward development of ketone therapies, we investigated the effect of chronic oral ketone ester (KE) supplementation as a prevention or treatment strategy in rodent heart failure models. METHODS: Two independent rodent heart failure models were used for the studies: transverse aortic constriction/myocardial infarction (MI) in mice and post-MI remodeling in rats. Seventy-five mice underwent a prevention treatment strategy with a KE comprised of hexanoyl-hexyl-3-hydroxybutyrate KE (KE-1) diet, and 77 rats were treated in either a prevention or treatment regimen using a commercially available ß-hydroxybutyrate-(R)-1,3-butanediol monoester (DeltaG; KE-2) diet. RESULTS: The KE-1 diet in mice elevated ß-hydroxybutyrate levels during nocturnal feeding, whereas the KE-2 diet in rats induced ketonemia throughout a 24-hour period. The KE-1 diet preventive strategy attenuated development of left ventricular dysfunction and remodeling post-transverse aortic constriction/MI (left ventricular ejection fraction±SD, 36±8 in vehicle versus 45±11 in KE-1; P=0.016). The KE-2 diet therapeutic approach also attenuated left ventricular dysfunction and remodeling post-MI (left ventricular ejection fraction, 41±11 in MI-vehicle versus 61±7 in MI-KE-2; P<0.001). In addition, ventricular weight, cardiomyocyte cross-sectional area, and the expression of ANP (atrial natriuretic peptide) were significantly attenuated in the KE-2-treated MI group. However, treatment with KE-2 did not influence cardiac fibrosis post-MI. The myocardial expression of the ketone transporter and 2 ketolytic enzymes was significantly increased in rats fed KE-2 diet along with normalization of myocardial ATP levels to sham values. CONCLUSIONS: Chronic oral supplementation with KE was effective in both prevention and treatment of heart failure in 2 preclinical animal models. In addition, our results indicate that treatment with KE reprogrammed the expression of genes involved in ketone body utilization and normalized myocardial ATP production following MI, consistent with provision of an auxiliary fuel. These findings provide rationale for the assessment of KEs as a treatment for patients with heart failure.

Machine Learned Cellular Phenotypes in Cardiomyopathy Predict Sudden Death.

RATIONALE: Susceptibility to VT/VF (ventricular tachycardia/fibrillation) is difficult to predict in patients with ischemic cardiomyopathy either by clinical tools or by attempting to translate cellular mechanisms to the bedside. OBJECTIVE: To develop computational phenotypes of patients with ischemic cardiomyopathy, by training then interpreting machine learning of ventricular monophasic action potentials (MAPs) to reveal phenotypes that predict long-term outcomes. METHODS AND RESULTS: We recorded 5706 ventricular MAPs in 42 patients with coronary artery disease and left ventricular ejection fraction ≤40% during steady-state pacing. Patients were randomly allocated to independent training and testing cohorts in a 70:30 ratio, repeated K=10-fold. Support vector machines and convolutional neural networks were trained to 2 end points: (1) sustained VT/VF or (2) mortality at 3 years. Support vector machines provided superior classification. For patient-level predictions, we computed personalized MAP scores as the proportion of MAP beats predicting each end point. Patient-level predictions in independent test cohorts yielded c-statistics of 0.90 for sustained VT/VF (95% CI, 0.76-1.00) and 0.91 for mortality (95% CI, 0.83-1.00) and were the most significant multivariate predictors. Interpreting trained support vector machine revealed MAP morphologies that, using in silico modeling, revealed higher L-type calcium current or sodium-calcium exchanger as predominant phenotypes for VT/VF. CONCLUSIONS: Machine learning of action potential recordings in patients revealed novel phenotypes for long-term outcomes in ischemic cardiomyopathy. Such computational phenotypes provide an approach which may reveal cellular mechanisms for clinical outcomes and could be applied to other conditions.

Transferrin improved the generation of cardiomyocyte from human pluripotent stem cells for myocardial infarction repair.

Human pluripotent stem cell (hPSC)-derived cardiomyocytes (CMs) hold great promise for the repair of the injured heart, but optimal cell production in a fully chemically defined and cost-effective system is essential for the efficacy and safety of cell transplantation therapies. In this study, we provided a simple and efficient strategy for cardiac differentiation from hPSCs and performed functional evaluation in a rat model of myocardial infarction. Using a chemically defined medium including four components, recombinant human albumin, ascorbic acid, human transferrin, and RPMI 1640, we developed a manageable and cost-effective protocol for robust generation of CMs from hPSCs. Interestingly, the addition of transferrin helped hPSCs to transit from TeSR-E8 medium to the simple cardiac differentiation medium and successfully initiated mesoderm differentiation without significant cell death. The CM generation efficiency was up to 85% based on cTnT expression. We performed transcriptome profiling from differentiation day 0 to 35, and characterized interesting dynamic change of cardiac genes. CMs derived from transferrin-supplemented simple medium have similar transcriptome and the maturation level compared to those generated in B27 minus insulin medium as well as their in vivo counterparts. Importantly, after transplantation, hPSC-derived CMs survived in the infarcted rat heart, significantly improved the physiological function and reduced fibrosis. Our study offers an easy-to-use and cost-effective method for cardiac differentiation and facilitates the translational application of hPSC-derived CMs for heart repair.

The cardioprotective and anxiolytic effects of Chaihujialonggumuli granule on rats with anxiety after acute myocardial infarction is partly mediated by suppression of CXCR4/NF-κB/GSDMD pathway.

AIMS: Over-expression of CXCR4 activates nuclear translocation of NF-κB, induces high expression of NLRP3, GSDMD, IL-1ß and IL-18, which promotes severe inflammatory response following myocardial infarction. Previous studies revealed inflammation induces anxiety after myocardial infarction. The Chaihujialonggumuli granule has anti-inflammatory properties and could tranquillize mind. But the mechanism of its efficacy remains unknown. This study was to investigate the possible mechanism of BFG on cardioprotective and anxiolytic. METHODS: The expression of CXCR4, NF-κB, NLRP3and GSDMD was measured with western-blot, QRT-PCR. The expression location of CXCR4, NLRP3, GSDMD were determined by immunohistochemistry. IL-1ß、IL-18 in the peripheral blood were measured by ELISA. HE staining, Masson staining and transmission electron microscopy were used to observe morphological changes of cardiomyocytes. Echocardiography was used to assess cardiac function after cardiac surgery. Elevated cross maze test and open field test were used to evaluate behaviours. Western blot was used to detect the protein expressions of 5-HT, DA, IL-1ß, IL-18 and neuron damage was investigated by Nissl staining in the hippocampus. RESULTS: The up-regulation of CXCR4, NF-κB, NLRP3 and GSDMD were found in the infarcted area after left coronary artery ligation. Pathological staining and analysis showed that more severe inflammatory cytokines infiltration, myocardial fibrosis, were found in myocardial tissue of the complex group rats. And when compared to the sham group, the levels of IL-1ß, IL-18 was increased of the complex group in both peripheral blood and brain. Behavioural test and echocardiography indicated that the rats in complex group exploration behaviours was significantly reduced, and with poor cardiac functional recovery. The AMD3100 had an inhibitory impact of CXCR4 on the activition of its downstream effectors, alleviating inflammatory reaction. Furthermore, the BFG decreased the expression level of CXCR4, NF-κB, GSDMD, NLRP3 in the infarcted area after myocardial infarction, when compared to the complex group. The assays in the brain indicated the BFG suppressed expression and activity of IL-1ß, IL-18, and improved 5-HT and DA synthesis. CONCLUSIONS: In sum, our study indicated that BFG may reduce inflammation, treat co-existing anxiety after myocardial infarction through inhibition of CXCR4/NF-κB/GSDMD signalling.