Assessment of cardiac function in large animal telemetry studies: Model sensitivity and historical results

Background: Cardiac expression of the Ca-dependent inotropic protein S100A1 is decreased in human end-stage heart failure (HF) and cardiomyocyte-targeted viral-based S100A1 gene transfer rescued failing myocardium in small animal models in vivo and in vitro via improved systolic and diastolic sarcoplasmic reticulum Ca-handling. We therefore hypothesized that cardioselective AAV9-S100A1 gene therapy will improve cardiac performance in a large animal experimental HF model under clinical conditions. Methods and Results: Left ventricular (LV) posterolateral myocardial infarction (MI) was induced in pigs by occlusion of the left coronary circumflex artery and resulted in LV failure (HF) 2 weeks post-MI reflected by a 40% and 27% reduction in LV +dp/dt max. and EF, respectively, as assessed by LV catheterization and echocardiography. Post-MI HF pigs were then randomized for retroinfusion of AAV9-luciferase (luc; n=6, 1.5×10 13 total viral particles, tvp) and AAV9-S100A1 (S100A1; n=6, 1.5×10 13 tvp) driven by a cardioselective promoter via the anterior cardiac vein while the left anterior descending artery was temporarily occluded. 14 weeks after cardiac gene transfer, the S100A1-treated HF group showed significantly enhanced S100A1 protein expression (+46.7±17.9%, P<0.05 vs. control groups) in targeted remote LV myocardium and improved indices of cardiac function and remodeling (luc vs. S100A1: +dp/dtmax: 983±81 vs. 1526±83 mmHg/s, EF: 39±2.1 vs. 61±3.7 %, P<0.05 S100A1 vs. luc, LV endsystolic diameter: luc 4.45±0.1 vs. S100A1 3.43 ±0.1 cm, P<0.05 S100A1 vs. luc, HR: 72±4 vs. 69±2, beats/min, P=n.s. S100A1 vs. luc). Importantly, analyses of renal, hepatic and hematopoetic function showed no alteration as assessed by unchanged transaminases, retention values and white blood cell counts compared to sham pigs. Conclusions: Our translational study provides proof of concept that AAV9-S100A1 based HF gene therapy is feasible and restores cardiac function in a large animal HF model under clinical conditions. Next, certified toxicological analysis and different AAV9-S100A1 dosage protocols will be assessed to eventually advance to first phase I/II clinical studies determining therapeutic efficiency of cardiac S100A1 gene therapy in HF patients.

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Application of a cloud analysis program for beat to beat analysis of cardiac function in large animal telemetry

Journal of Pharmacological and Toxicological Methods ◽

10.1016/j.vascn.2015.08.071 ◽

2015 ◽

Vol 75 ◽

pp. 178-179

Author(s):

Lewis Buchanan ◽

William Warner ◽

Geoff Lewen ◽

Paul Levesque ◽

Michael Gill

Keyword(s):

Cardiac Function ◽

Large Animal ◽

Analysis Program ◽

Cloud Analysis

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Abstract 16434: Temporal Metabolomic and Transcriptomic Changes in a Large-Animal Model of Hfpef

Circulation ◽

10.1161/circ.142.suppl_3.16434 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Andrew A Gibb ◽

Emma K Murray ◽

Deborah M Eaton ◽

Anh T Huynh ◽

Dhanendra Tomar ◽

...

Keyword(s):

Cardiac Function ◽

Disease Progression ◽

Mitochondrial Function ◽

Pulmonary Mechanics ◽

Pathway Enrichment Analysis ◽

Sham Operation ◽

Large Animal ◽

Aortic Banding ◽

Metabolomics Data ◽

Lipid Species

Heart failure with preserved ejection fraction (HFpEF) accounts for ~50% of HF cases, with no effective treatments. We previously reported that a feline aortic banding model recapitulates many of the multi-factorial features of HFpEF, including: LV hypertrophy, left atrial enlargement, elevated LV filling pressures, impaired pulmonary mechanics and fibrosis. Importantly, this model lacks obesity and hypertension enabling the discovery of cardiac centric targets independent of comorbidities. We examined early changes in metabolism and transcription to gain mechanistic insight into HFpEF development. Male short-hair kittens (2mo old) underwent aortic banding or sham operation. Cardiac function was assessed at baseline and 1mo post-banding prior to tissue collection and downstream analyses. Following banding, we observed significant cardiac hypertrophy and initiation of LV fibrosis in the absence of changes in cardiac function. We observed LV mitochondrial dysfunction, indicated by impaired complex-I and -II respiration prompting the examination of cardiac metabolism by unbiased metabolomics. 82 metabolites were significantly different (≥ 1.25 fold, p ≤ 0.1) between 1mo banded and sham hearts, with an overrepresentation of amino acid (aa) and lipid species. Pathway enrichment analysis highlighted an increase in aa metabolism (e.g. serine, proline) that is associated with ECM remodeling and tissue fibrosis. Additionally, an increase in lipid species (i.e. acyl-carnitines) suggests reduced fatty acid utilization and a shift towards glycolysis. Correlations of metabolomics data with mitochondrial function and cardiac phenotyping revealed strong associations between mitochondrial function and the cardiac energy state, as well as aa and LV fibrosis. RNA-seq and enrichment analyses revealed a significant inflammatory response early in disease progression and a decrease in protein/histone acetylation. Collectively, this systems-based approach provides new insights into the cellular biology underlying HFpEF-like disease progression. The metabolic and transcriptional signature that precede the clinical features of HFpEF, will provide new pre-clinical research directions and may yield novel therapeutic targets.

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Abstract 113: SUMO1 Gene Transfer Rescues Cardiac Function in a Large Animal Model of Heart Failure

Circulation Research ◽

10.1161/res.111.suppl_1.a113 ◽

2012 ◽

Vol 111 (suppl_1) ◽

Author(s):

Lisa M Tilemann ◽

Kiyotake Ishikawa ◽

Changwon Kho ◽

Ahyoung Lee ◽

Jaime Aguero ◽

...

Keyword(s):

Heart Failure ◽

Gene Transfer ◽

Cardiac Function ◽

Therapeutic Potential ◽

Critical Role ◽

Balloon Occlusion ◽

Large Animal Model ◽

Swine Model ◽

Large Animal ◽

Cardiac Sarcoplasmic Reticulum

Recently, small ubiquitin-related modifier 1 (SUMO1) was found to enhance the activity and stability of the cardiac sarcoplasmic reticulum Ca2+ ATPase, SERCA2a. In both, human and rodent models of heart failure (HF), the total amount of myocardial SUMO1 is decreased and its knock down results in severe HF. Adeno-associated vector (AAV) mediated SUMO1 gene transfer significantly improves cardiac function in murine models of HF. As a critical step towards clinical translation, we evaluated the effects of SUMO1 gene transfer in a swine model of ischemic heart failure. One month after balloon occlusion of the proximal LAD, 21 animals were randomized to receive either AAV1.SUMO1 at two doses, AAV1.SERCA2a, AAV1.SUMO1+AAV1.SERCA2a, or saline via antegrade coronary infusion. In addition, three pigs served as controls and underwent sham procedures. The ejection fraction and the maximum dP/dt significantly increased after gene transfer of SUMO1 at both doses, SERCA2a and the combination of SUMO1 and SERCA2a (p=0.034, p=0.028) compared to saline infusion. The increase in maximum dP/dt was most pronounced in the group that received both SUMO1 and SERCA2a. Furthermore, the increase in end-systolic and end-diastolic volumes was normalized in the treatment groups, while they further deteriorated in the saline group (p=0.001, p=0.022). SUMO1 and SERCA2a gene transfer significantly improved cardiac function and concomitant gene delivery of SUMO1 and SERCA2a had a synergistic effect on improving these parameters in the HF animals. These results strongly support the critical role of SUMO1 for SERCA2a function and underline the therapeutic potential in heart failure patients.

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Cardiac Function in a Long-Term Follow-Up Study of Moderate and Severe Porcine Model of Chronic Myocardial Infarction

BioMed Research International ◽

10.1155/2015/209315 ◽

2015 ◽

Vol 2015 ◽

pp. 1-11 ◽

Cited By ~ 3

Author(s):

Renate de Jong ◽

Gerardus P. J. van Hout ◽

Jaco H. Houtgraaf ◽

S. Takashima ◽

Gerard Pasterkamp ◽

...

Keyword(s):

Cardiac Function ◽

Ischemia Reperfusion ◽

Time Frame ◽

Large Animal Model ◽

Large Animal ◽

Loop Analysis ◽

Circumflex Artery ◽

Left Circumflex Artery ◽

2D Echocardiography

Background. Novel therapies need to be evaluated in a relevant large animal model that mimics the clinical course and treatment in a reasonable time frame. To reliably assess therapeutic efficacy, knowledge regarding the translational model and the course of disease is needed.Methods. Landrace pigs were subjected to a transient occlusion of the proximal left circumflex artery (LCx)(n=6)or mid-left anterior descending artery (LAD)(n=6)for 150 min. Cardiac function was evaluated before by 2D echocardiography or 3D echocardiography and pressure-volume loop analysis. At 12 weeks of follow-up the heart was excised for histological analysis and infarct size calculations.Results. Directly following AMI, LVEF was severely reduced compared to baseline in the LAD group-17.1±1.6%, P=0.009compared to only a moderate reduction in the LCx group-5.9±1.5%, P=0.02and this effect remained unchanged during 12 weeks of follow-up.Conclusion. Two models of chronic MI, representative for different patient groups, can reproducibly be created through clinically relevant ischemia-reperfusion of the mid-LAD and proximal LCx.

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A Bioengineered Neuregulin-Hydrogel Therapy Reduces Scar Size and Enhances Post-Infarct Ventricular Contractility in an Ovine Large Animal Model

Journal of Cardiovascular Development and Disease ◽

10.3390/jcdd7040053 ◽

2020 ◽

Vol 7 (4) ◽

pp. 53

Author(s):

Jeffrey E. Cohen ◽

Andrew B. Goldstone ◽

Hanjay Wang ◽

Brendan P. Purcell ◽

Yasuhiro Shudo ◽

...

Keyword(s):

Cardiac Function ◽

Systolic Pressure ◽

Left Ventricular ◽

Left Ventricular Ejection ◽

Coronary Artery Ligation ◽

Large Animal ◽

Ventricular Contractility ◽

Intramyocardial Injection ◽

Ventricular Ejection Fraction ◽

Scar Size

The clinical efficacy of neuregulin (NRG) in the treatment of heart failure is hindered by off-target exposure due to systemic delivery. We previously encapsulated neuregulin in a hydrogel (HG) for targeted and sustained myocardial delivery, demonstrating significant induction of cardiomyocyte proliferation and preservation of post-infarct cardiac function in a murine myocardial infarction (MI) model. Here, we performed a focused evaluation of our hydrogel-encapsulated neuregulin (NRG-HG) therapy’s potential to enhance cardiac function in an ovine large animal MI model. Adult male Dorset sheep (n = 21) underwent surgical induction of MI by coronary artery ligation. The sheep were randomized to receive an intramyocardial injection of saline, HG only, NRG only, or NRG-HG circumferentially around the infarct borderzone. Eight weeks after MI, closed-chest intracardiac pressure–volume hemodynamics were assessed, followed by heart explant for infarct size analysis. Compared to each of the control groups, NRG-HG significantly augmented left ventricular ejection fraction (p = 0.006) and contractility based on the slope of the end-systolic pressure–volume relationship (p = 0.006). NRG-HG also significantly reduced infarct scar size (p = 0.002). Overall, using a bioengineered hydrogel delivery system, a one-time dose of NRG delivered intramyocardially to the infarct borderzone at the time of MI in adult sheep significantly reduces scar size and enhances ventricular contractility at 8 weeks after MI.

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A Large Animal Model of Diminished Cardiac Function: Monensin Toxicosis in the Bovine Calf

Journal of Cardiac Failure ◽

10.1016/j.cardfail.2005.06.181 ◽

2005 ◽

Vol 11 (6) ◽

pp. S138

Keyword(s):

Animal Model ◽

Cardiac Function ◽

Large Animal Model ◽

Large Animal

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Towards regenerating the mammalian heart: challenges in evaluating experimentally induced adult mammalian cardiomyocyte proliferation

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00697.2015 ◽

2016 ◽

Vol 310 (9) ◽

pp. H1045-H1054 ◽

Cited By ~ 39

Author(s):

David C. Zebrowski ◽

Robert Becker ◽

Felix B. Engel

Keyword(s):

Cell Cycle ◽

Cardiac Function ◽

Therapeutic Target ◽

Cell Cycle Regulation ◽

Animal Studies ◽

Large Animal ◽

Cardiomyocyte Proliferation ◽

Mammalian Heart ◽

Cycle Regulation

In recent years, there has been a dramatic increase in research aimed at regenerating the mammalian heart by promoting endogenous cardiomyocyte proliferation. Despite many encouraging successes, it remains unclear if we are any closer to achieving levels of mammalian cardiomyocyte proliferation for regeneration as seen during zebrafish regeneration. Furthermore, current cardiac regenerative approaches do not clarify whether the induced cardiomyocyte proliferation is an epiphenomena or responsible for the observed improvement in cardiac function. Moreover, due to the lack of standardized protocols to determine cardiomyocyte proliferation in vivo, it remains unclear if one mammalian regenerative factor is more effective than another. Here, we discuss current methods to identify and evaluate factors for the induction of cardiomyocyte proliferation and challenges therein. Addressing challenges in evaluating adult cardiomyocyte proliferation will assist in determining 1) which regenerative factors should be pursued in large animal studies; 2) if a particular level of cell cycle regulation presents a better therapeutic target than another (e.g., mitogenic receptors vs. cyclins); and 3) which combinatorial approaches offer the greatest likelihood of success. As more and more regenerative studies come to pass, progress will require a system that not only can evaluate efficacy in an objective manner but can also consolidate observations in a meaningful way.

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