			Home About us Contact

Cardiac Phenotype (cardiac + phenotype)

Distribution by Scientific Domains

Medical Sciences	50%
Life Sciences	50%

Selected Abstracts

BMP-2 and FGF-2 Synergistically Facilitate Adoption of a Cardiac Phenotype in Somatic Bone Marrow c-kit+/Sca-1+ Stem Cells

CLINICAL AND TRANSLATIONAL SCIENCE, Issue 2 2008
Brent R. DeGeorge, Jr. B.S.
Abstract The aim of this study was to explore the effect of bone morphogenetic protein-2 (BMP-2) and fibroblast growth factor-2 (FGF-2), paracrine factors implicated in both cardiac embryogenesis and cardiac repair following myocardial infarction (MI),on murine bone marrow stem cell (mBMSC) differentiation in an ex vivo cardiac microenvironment. For this purpose, green fluorescent protein (GFP) expressing hematopoietic lineage negative (lin-) c-kit ligand (c-kit) and stem cell antigen-1 (Sca-1) positive (GFP-lin-/c-kit+/sca+) mBMSC were co-cultured with neonatal rat ventricular cardiomyocytes (NVCMs). GFP+ mBMSC significantly induced the expression of BMP-2 and FGF-2 in NVCMs, and approximately 4% GFP+ mBMSCs could be recovered from the co-culture at day 10. The addition of BMP-2 in concert with FGF-2 significantly enhanced the amount of integrated GFP+ mBMSCs by 5-fold (,20%), whereas the addition of anti-BMP-2 and/or anti-FGF-2 antibodies completely abolished this effect. An analysis of calcium cycling revealed robust calcium transients in GFP+ mBMSCs treated with BMP-2/FGF-2 compared to untreated co-cultures. BMP-2 and FGF-2 addition led to a significant induction of early (NK2 transcription factor related, locus 5; Nkx2.5, GATA binding protein 4; GATA-4) and late (myosin light chain kinase [MLC-2v], connexin 43 [Cx43]) cardiac marker mRNA expression in mBMSCs following co-culture. In addition, re-cultured fluorescence-activated cell sorting (FACS)-purified BMP-2/FGF-2-treated mBMSCs revealed robust calcium transients in response to electrical field stimulation which were inhibited by the L-type calcium channel (LTCC) inhibitor, nifedipine, and displayed caffeine-sensitive intracellular calcium stores. In summary, our results show that mBMSCs can adopt a functional cardiac phenotype through treatment with factors essential to embryonic cardiogenesis that are induced after cardiac ischemia. This study provides the first evidence that mBMSCs with long-term self-renewal potential possess the capability to serve as a functional cardiomyocyte precursor through the appropriate paracrine input and cross-talk within an appropriate cardiac microenvironment. [source]

Characterization of the cardiac phenotype in neonatal Ts65Dn mice

DEVELOPMENTAL DYNAMICS, Issue 2 2008
Austin D. Williams
Abstract The Ts65Dn mouse is the most-studied of murine models for Down syndrome. Homology between the triplicated murine genes and those on human chromosome 21 correlates with shared anomalies of Ts65Dn mice and Down syndrome patients, including congenital heart defects. Lethality is associated with inheritance of the T65Dn chromosome, and anomalies such as right aortic arch with Kommerell's diverticulum and interrupted aortic arch were found in trisomic neonates. The incidence of gross vascular abnormalities was 17% in the trisomic population. Histological analyses revealed interventricular septal defects and broad foramen ovale, while immunohistochemistry showed abnormal muscle composition in the cardiac valves of trisomic neonates. These findings confirm that the gene imbalance present in Ts65Dn disrupts crucial pathways during cardiac development. The candidate genes for congenital heart defects that are among the 104 triplicated genes in Ts65Dn mice are, therefore, implicated in the dysregulation of normal cardiogenic pathways in this model. Developmental Dynamics 237:426,435, 2008. © 2007 Wiley-Liss, Inc. [source]

Cardiovascular magnetic resonance reveals similar damage to the heart of patients with becker and limb-girdle muscular dystrophy but no cardiac symptoms

JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2009
Ali Yilmaz MD
Abstract Cardiac involvement in patients with a sarcoglycanopathy (limb-girdle muscular dystrophy) has been described previously; however, this is the first cardiovascular magnetic resonance (CMR) study in such a patient demonstrating an interesting pattern of myocardial damage using late gadolinium enhancement (LGE) imaging. Moreover, the wall motion abnormality and the subepicardial pattern of LGE in this patient with a sarcoglycanopathy is in agreement with the findings in another patient with Becker muscular dystrophy. The predominance of LGE in the subepicardial layers of the left ventricular inferolateral wall suggests that such a myocardial damage pattern represents a nonspecific cardiac phenotype in response to exaggerated mechanical stress in this region, at least in patients with a sarcoglycanopathy or dystrophinopathy. J. Magn. Reson. Imaging 2009;30:876,877. © 2009 Wiley-Liss, Inc. [source]

Proteomic insights into cardiac cell death and survival

PROTEOMICS - CLINICAL APPLICATIONS, Issue 6 2008
W. Robb MacLellan
Abstract Cardiovascular disease is the leading cause of death and disability in the developed world. To design novel therapeutic strategies to treat and prevent this disease, better understanding of cardiac cell function is necessary. In addition to (and, indeed, in combination with) genetics, physiology and molecular biology, proteomics plays a critical role in our understanding of cardiovascular systems at multiple scales. The purpose of this review is to examine recent developments in the field of myocardial injury and protection, examining how proteomics has informed investigations into organelles, signaling complexes, and cardiac phenotype. [source]

BMP-2 and FGF-2 Synergistically Facilitate Adoption of a Cardiac Phenotype in Somatic Bone Marrow c-kit+/Sca-1+ Stem Cells

Age-dependent cardiomyopathy in mitochondrial mutator mice is attenuated by overexpression of catalase targeted to mitochondria

AGING CELL, Issue 4 2010
Dao-Fu Dai
Summary Mitochondrial defects have been found in aging and several age-related diseases. Mice with a homozygous mutation in the exonuclease encoding domain of mitochondrial DNA polymerase gamma (Polgm/m) are prone to age-dependent accumulation of mitochondrial DNA mutations and have shown a broad spectrum of aging-like phenotypes. However, the mechanism of cardiac phenotypes in relation to the role of mitochondrial DNA mutations and oxidative stress in this mouse model has not been fully addressed. We demonstrate age-dependent cardiomyopathy in Polgm/m mice, which by 13,14 months of age displays marked cardiac hypertrophy and dilatation, impairment of systolic and diastolic function, and increased cardiac fibrosis. This age-dependent cardiomyopathy is associated with increases in mitochondrial DNA (mtDNA) deletions and protein oxidative damage, increased expression of apoptotic and senescence markers, as well as a decline in signaling for mitochondrial biogenesis. The relationship of these changes to mitochondrial reactive oxygen species (ROS) was tested by crossing Polgm/m mice with mice that overexpress mitochondrial targeted catalase (mCAT). All of the above phenotypes were partially rescued in Polgm/m/mCAT mice. These data indicate that accumulation of mitochondrial DNA damage with age can lead to cardiomyopathy and that this phenotype is partly mediated by mitochondrial oxidative stress. [source]