Posts in Category: Heart Failure & Cardiac Disease

Induced Pluripotent Stem Cells 10 Years Later For Cardiac Applications

Induced Pluripotent Stem Cells 10 Years Later: For Cardiac Applications

Yoshinori Yoshida, Shinya Yamanaka

Factors which possibly cause clonal differences of induced pluripotent stem cells (iPSCs). [Powerpoint File]

Induced Pluripotent Stem Cells 10 Years Later: For Cardiac Applications

Induced Pluripotent Stem Cells 10 Years Later: For Cardiac Applications

Yoshinori Yoshida, Shinya Yamanaka

Patient stratification based on drug responsiveness using induced pluripotent stem cells–derived cardiac myocytes. [Powerpoint File]

Critical Issues for the Translation of Cardioprotection

Critical Issues for the Translation of Cardioprotection

Gerd Heusch

Lack of robust preclinical data, lack of phase II dosing and timing studies, and too loose inclusion criteria in clinical trials contribute to poor translation. Adapted from Rossello and Yellon6 with permission of the publisher. Copyright ©2016, American Heart Association, Inc. Authorization for this adaptation has been obtained both from the owner of the copyright in the original work and from the owner of copyright in the translation or adaptation. TIMI indicates thrombolysis in myocardial infarction. [Powerpoint File]

Cell Therapy Trials in Congenital Heart Disease

Cell Therapy Trials in Congenital Heart Disease

Hidemasa Oh

Preclinical study of intracoronary cardiosphere-derived cell (CDC) infusion in a rat model of right heart failure. A–K, Pulmonary artery (PA) banding was created to induce pressure overload right heart failure in rats (weighing 250–300 g). The left thorax was opened to expose the pulmonary artery. A silk suture was tied tightly around an 18-gauge needle alongside the pulmonary artery, followed by a rapid removal of the needle to leave the pulmonary artery constricted in the lumen equal to the diameter of the needle. Intracoronary infusion was performed 4 weeks after pulmonary artery banding. The ascending aorta and the pulmonary artery were occluded with a snare twice for a 20-s interval, 10 min apart, during which time rats received an infusion of CDCs or vehicle into the aortic root directly. Animals were euthanized at 4 weeks after treatment to obtain immuno-histological data. Masson-trichrome staining and hematoxylin and eosin (H&E) staining are shown. One month after pulmonary artery banding, significant right ventricular hypertrophy and fibrosis were observed. Note that CDC treatment reduced cardiac fibrosis, but not hypertrophy, one month after infusion (F and I). Bars, 2 mm in A to C; 20 μm in D to I. J, Animals were separated into 4 groups: (1) sham-operated animals (n=12), (2) rats subjected to pulmonary artery banding for 4 weeks with vehicle treatment (n=12), and (3 and 4) rats subjected to banding for 4 weeks with 2 doses of CDC infusion (0.5×105 or 1×105 cells: n=12 in each). Cardiac fibrosis induced by right ventricle pressure overload was measured. CDC infusion significantly reduced the fibrotic area in a cell dose-dependent manner. K, CDC treatment did not affect the diameter of myocytes, which are mechanically enlarged by pressure overload. L, Rat CDCs were infected by lentiviral vectors harboring human cytomegalovirus promoter-driven LacZ reporter gene and were subjected to intracoronary transfer into rats 4 weeks after pulmonary artery banding. Clear CDC engraftment could be detected along the endocardium and surrounding capillary vessels where the cells had been injected. M, Cardiomyocytes were stained with α-sarcomeric actin (red). Newly regenerated LacZ-positive cardiac muscle cells could be detected by β-galactosidase staining (green). Substantial cardiomyocyte regeneration was verified 4 weeks after CDC delivery. Bars, 50 μm. N, Engrafted LacZ-positive CDCs were evaluated by X-gal staining and corrected by the number of total nuclei appreciated within the respective area. Fibrotic and nonfibrotic areas were determined by Masson-trichrome staining derived from serial sections. O, Differentiated cardiomyocytes after CDC infusion were verified by the cells coexpressing both α-sarcomeric actin (red) and β-galactosidase (LacZ, green). The frequency of the cells coexpressing α-sarcomeric actin among the β-galactosidase–positive cells is shown. Data are expressed as the means (SD). [Powerpoint File]

Contemporary Approaches to Modulating the Nitric Oxide–cGMP Pathway in Cardiovascular Disease

Contemporary Approaches to Modulating the Nitric Oxide–cGMP Pathway in Cardiovascular Disease

Jan R. Kraehling, William C. Sessa

Proteins and enzymes involved in the nitric oxide (NO)-nitric oxide–sensitive guanylate cyclase (NOsGC)–cGMP pathway and its modulators. Key players of the pathway are shown in blue, the positive modulators are shown in yellow, and the negative modulators in purple. Endothelial cells (EC) are shown in green (top), whereas the vascular smooth muscle cell (VSMC) is shown in red (bottom). The space between the 2 cells is called myoendothelial junction (MEJ). cGMP mediates its cellular functions through cGMP-modulated (cyclic nucleotide-gated [CNG]) cation channels, cGMP-dependent protein kinases (cGKs) and cGMP-regulated phosphodiesterases (PDEs). BH4 indicates tetrahydrobiopterin; CAV1, caveolin-1; CYB5R3, NADH-cytochrome b5 reductase 3; eNOS, endothelial nitric oxide synthase (NOS3); Hb2+/Hb3+, hemoglobin α (reduced/oxidized); and PDE, phosphodiesterase. [Powerpoint File]

Contemporary Approaches to Modulating the Nitric Oxide–cGMP Pathway in Cardiovascular Disease

Contemporary Approaches to Modulating the Nitric Oxide–cGMP Pathway in Cardiovascular Disease

Jan R. Kraehling, William C. Sessa

Mechanism of action of nitric oxide–sensitive guanylate cyclase (NOsGC) stimulators and activators. NOsGC stimulators bind to the enzyme and act in an allosteric manner. NO and NOsGC stimulators enhance the NOsGC activity synergistically. NOsGC activators occupy the heme binding site and work therefore only additively with NO. The oxidation of the heme-Fe2+ to heme-Fe3+ results in a weaker binding of heme to NOsGC, hence allowing the NOsGC activators to occupy the heme binding site easier. The schematic is derived from Zorn and Wells.111 [Powerpoint File]

Myocardial Viability: Survival Mechanisms and Molecular Imaging Targets in Acute and Chronic Ischemia

Myocardial Viability: Survival Mechanisms and Molecular Imaging Targets in Acute and Chronic Ischemia

Henry Gewirtz, Vasken Dilsizian

Diagrammatic representation of myocardial cell and potential targets of radiotracer imaging and mapping of the surface renin–angiotensin system. ACE indicates angiotensin-converting enzyme; AGT, angiotensinogen; Ang II, angiotensin II; AT1R, angiotensin II type 1 receptor; and AT2R, angiotensin II type 2 receptor. Reproduced with permission from Schindler and Dilsizian.61 Copyright © 2012, Elsevier. [Powerpoint File]

Gut Microbiota in Cardiovascular Health and Disease

Gut Microbiota in Cardiovascular Health and Disease

W.H. Wilson Tang, Takeshi Kitai, Stanley L. Hazen

Gut microbiota and possible molecular pathways linked to cardiovascular and cardiometabolic diseases. BAT indicates brown adipose tissue; FXR, farnesoid X receptor; GLP, glucagon-like peptide; GPR, G-protein–coupled receptor; LPS, lipopolysaccharide; PYY, peptide YY; TLR, toll-like receptor; TMA, trimethylamine; and TMAO, trimethylamine N-oxide. [Powerpoint File]

Myocardial Viability: Survival Mechanisms and Molecular Imaging Targets in Acute and Chronic Ischemia

Myocardial Viability: Survival Mechanisms and Molecular Imaging Targets in Acute and Chronic Ischemia

Henry Gewirtz, Vasken Dilsizian

Myocyte metabolic pathways outlined for glucose and fatty acid metabolism with focus on the mitochondrion. The electron transport chain (ETC), complexes I–V, is a series of proton pumps. The last of which, complex V, supplies protons to a proton-sensitive ATPase and thereby generates ATP. CPT1,2 indicates carnitine palmitoyltransferase 1,2; FA, fatty acid; PDH, pyruvate dehydrogenase; and TCA, tricarboxylic acid (Krebs cycle). Reproduced with permission from Huss and Kelly.30 Copyright © 2005, American Society for Clinical Investigation. [Powerpoint File]

Myocardial Viability: Survival Mechanisms and Molecular Imaging Targets in Acute and Chronic Ischemia

Myocardial Viability: Survival Mechanisms and Molecular Imaging Targets in Acute and Chronic Ischemia

Henry Gewirtz, Vasken Dilsizian

Key myocyte organelles and ion channels and their function under conditions of ischemia and reperfusion. Ischemia (left panel) causes influx of Ca2+ and decline in pH, both of which, if not severe, facilitate maintenance of closed mitochondrial permeability transition pore (mPTP). On reperfusion (right panel), key events include restoration of physiological pH, burst of reactive oxygen species (ROS) from mitochondria, release of Ca2+ from the sarcoplasmic reticulum (SR), and opening of mPTP which results in collapse of its Δψ. Reproduced with permission from Hausenloy and Yellon.27 Copyright © 2013, American Society for Clinical Investigation. [Powerpoint File]

Noninvasive Imaging in Adult Congenital Heart Disease

Noninvasive Imaging in Adult Congenital Heart Disease

Luke J. Burchill, Jennifer Huang, Justin T. Tretter, Abigail M. Khan, Andrew M. Crean, Gruschen R. Veldtman, Sanjiv Kaul, Craig S. Broberg

Three-dimensional (3D) echocardiographic quantification. In this example, left atrial and left ventricular volumes are measured using semiautomated border detection in a 3D echocardiogram. Ejection fraction can be derived without the geometric assumptions that limited 2D-derived measures, such as Simpson biplane and the area–length method. [Powerpoint File]

Noninvasive Imaging in Adult Congenital Heart Disease

Noninvasive Imaging in Adult Congenital Heart Disease

Luke J. Burchill, Jennifer Huang, Justin T. Tretter, Abigail M. Khan, Andrew M. Crean, Gruschen R. Veldtman, Sanjiv Kaul, Craig S. Broberg

Liver imaging in Fontan-associated liver disease. A, Contrast computed tomographic scan of upper abdomen in a patient with heterotaxy and a Fontan circulation demonstrating a well-circumscribed tumor measuring 5 cm in diameter in the right lobe of a midline liver (yellow asterix). B, Fluorodeoxyglucose-positron emission tomographic scan in the same patient demonstrating abnormal uptake in the right lobe of the liver in the region of the tumor. [Powerpoint File]

Current Interventional and Surgical Management of Congenital Heart Disease: Specific Focus on Valvular Disease and Cardiac Arrhythmias

Current Interventional and Surgical Management of Congenital Heart Disease: Specific Focus on Valvular Disease and Cardiac Arrhythmias

Kimberly A. Holst, Sameh M. Said, Timothy J. Nelson, Bryan C. Cannon, Joseph A. Dearani

Schematic representation of the possible lines of ablation to treat macro reentrant atrial tachycardia in the presence of various atrial anomalies associated with complex congenital heart disease. avn indicates atrioventricular node; CS, coronary sinus; FO, foramen ovale; HV, hepatic vein; IVC, inferior vena cava; LAA, left atrial appendage; LSVC, left superior vena cava; MV, mitral valve; PV, pulmonary valve; RAA, right atrial appendage; RSVC, right superior vena cava; TAPVR, total anomalous pulmonary venous return; and TV, tricuspid valve. Reproduced from Mavroudis et al53 with permission of the publisher. Copyright ©2008, The Society of Thoracic Surgeons. [Powerpoint File]

Gene Editing With CRISPR/Cas9 RNA-Directed Nuclease

Gene Editing With CRISPR/Cas9 RNA-Directed Nuclease

Thomas Doetschman, Teodora Georgieva

Large deletions, marker insertions, and single-nucleotide polymorphism (SNP) insertions. A, Multiple exons can be deleted by nonhomologous end joining (NHEJ) by designing single-guide RNAs (sgRNAs) that flank the region to be deleted. In the presence of Cas9 double-strand DNA breaks (DSBs) will occur resulting in small indels at the site of end joining. The double bar at the sgRNA:gene hybridization site represents the DSB caused by Cas9. Cas9 can be introduced as either mRNA or recombinant protein. B, Marker gene insertion can be achieved through homology-directed repair (HDR) in which the homologous regions are introduced in a plasmid as would be done by gene targeting. C, A chromosomal region deletion has been done using HDR in which 2 sgRNAs were designed at each end of the region to be deleted. The homology template was an single-strand DNA (ssDNA) oligo with homology at each end of the region to be deleted. D, SNP insertion using HDR with ssDNA oligo as homology template. [Powerpoint File]

Gene Editing With CRISPR/Cas9 RNA-Directed Nuclease

Gene Editing With CRISPR/Cas9 RNA-Directed Nuclease

Thomas Doetschman, Teodora Georgieva

Cas9 RNA-guided nuclease system. Schematic representation of the Streptococcus pyogenes Cas9 nuclease (green) targeted to genomic DNA by a single-guide RNA (sgRNA) consisting of an ≈20-nt guide sequence (blue) and a scaffold (red). The guide sequence is directly upstream of the protospacer adjacent motif (PAM), NGG (orange circles). Cas9 mediates a double-strand DNA break (DSB) ≈3 bp upstream of the PAM (red triangles). The break is repaired by 1 of 2 mechanisms: nonhomologous end joining (NHEJ) that creates random insertions or deletions at the target site or homology-directed repair (HDR). Two types of template can be used for HDR: small single-stranded DNA (ssDNA) oligonucleotide donor with short 60- 70-bp homology arms and a linear or circular dsDNA plasmid with long homology arms of 1 to 3 kb. [Powerpoint File]