Cardiovascular Gene Research Articles

423: Functional genomic analysis of TTTS recipient amniotic fluid supernatant reveals major alterations in nervous and cardiovascular system gene expression

amniotic fluid supernatant reveals major alterations in nervous and cardiovascular system gene expression LISA HUI, Heather Wick, Kenneth Moise, Anthony Johnson, Michael Belfort, Kirby Johnson, Diana Bianchi Tufts Medical Center, Mother Infant Research Institute, Boston, MA, Tufts University, Computer Science, Medford, MA, Baylor College of Medicine, Obstetrics and Gynecology, Houston, TX OBJECTIVE: To understand the molecular mechanisms underlying the recipient’s response to twin-twin transfusion syndrome (TTTS) and develop fetal biomarkers by performing functional genomic analysis of amniotic fluid supernatant (AFS). STUDY DESIGN: We have previously shown that AFS contains RNA from multiple fetal organs, including brain. This was a prospective study analyzing cell-free RNA transcripts in recipient AFS from women undergoing clinically-indicated laser surgery. Normal AFS was obtained from singleton fetuses undergoing genetic amniocentesis. The independent t test with the Benjamini-Hochberg correction was used to evaluate up-regulated genes in TTTS vs normal controls, and Quintero Stage III vs stage II cases. Functional analyses of the significantly up-regulated genes were performed with Ingenuity software. RESULTS: AFS samples from 8 recipient twins (4 Stage II and 4 Stage III, EGA 17-21 w) and 4 euploid controls (EGA 17-22 w) were included. Compared with controls, 811 genes were significantly upregulated in TTTS cases. The most statistically significant biological process that differed between cases and controls was nervous system development and function. There were 19 up-regulated nervous system genes in TTTS cases including microtubule-associated protein tau, a biomarker of adult neurodegeneration. Other important upregulated transcripts in TTTS were vascular endothelial growth factor 1 and angiotensin II receptor type 2. The most statistically significant up-regulated biological process in Stage III vs Stage II fetuses was cardiovascular disease. Among the 58 cardiovascular disease genes up-regulated in Stage III recipients were some specifically associated with hypertension and left ventricular dysfunction (TRPC4) and congenital pulmonary stenosis (NTRK3). CONCLUSION: Our study provides novel molecular evidence of the impact of TTTS on the developing nervous system. We also identified the cardiovascular genes specifically associated with Stage III vs Stage II disease. These results further our understanding of the pathophysiology of TTTS and provide potential prognostic fetal biomarkers. 424 Gender equality in fetal reduction (FR) patient decision preferences: major cultural change in the USA Mara Rosner, Stephanie Andriole, Avishai Alkalay, Rachel Greenbaum, Juliana Gebb, Mark Evans Montefiore Medical Center/Albert Einstein College of Medicine, Obstetrics & Gynecology and Women’s Health, Bronx, NY, Comprehensive Genetics, Genetic Counseling, New York, NY, Albert Einstein College of Medicine/ Montefiore Medical Center, Obstetrics and Gynecology & Women’s Health, Bronx, NY, Comprehensive Genetics, Ultrasound, New York, NY, Comprehensive Genetics & Mt. Sinai School of Medicine, Obstetrics & Gynecology, New York, NY OBJECTIVE: 20 years ago, a disproportionate % of gender preference requests for prenatal diagnosis, terminations, and reductions were from patients of ethnic groups that valued boys over girls. We refused to participate. As patient interest expanded to all ethnic groups and gender preference seemed to equalize, our bioethicist had us re-evaluate and incorporate patient preference. STUDY DESIGN: We prioritize FR decisions by: 1. documented major (M) anomaly; 2. suspicious or minor (m) findings; 3. if neither, we consider gender preference. We retrospectively reviewed patient choices in our last 400 CVS/FR cases starting with triplets or twins. Patients were categorized based on type of reduction (3i2, 3i1, or 2i1), presence or absence of M or m findings, and whether all fetuses were the same gender (SG) or a gender choice was possible. Higher order and non-CVS pregnancies were excluded. RESULTS: 178/321 (56%) had either M/m or SG. Of 3i2 with option, 71/79 reduced to M/F of which about 1/3rd had no preference. 1 chose MM and 7 chose FF. Most 3i1 included MZ twins for whom we reduced MZ in 33/35 cases. Of 20 3i1 with option, 10 chose M and 10 chose F. Of 44 2i1 with option, 20 chose M & 24 chose F. CONCLUSION: There has been a major shift in culture from a generation ago. Male preponderance has ended in the USA. The vast majority of our patients who reduced to 2 preferred one of each or had no preference. When reducing to 1, a non-significant trend towards female preference was found. In addition to identifying abnormalities, CVS prior to FR expands patient autonomy. Poster Session III Doppler Assessment, Fetus, Prematurity www.AJOG.org

Quantitative 3D Tracing of Gene-delivery Viral Vectors in Human Cells and Animal Tissues

Trafficking through a variety of cellular structures and organelles is essential for the interaction between gene-delivery vectors (i.e., adeno-associated virus (AAV) and liposomes) and host cells/tissues. Here, we present a method of computer-assisted quantitative 3D biodistribution microscopy that samples the whole population of fluorescently-labeled vectors and document their trafficking routes. Using AAV as a working model, we first experimentally defined numerical parameters for the singularity of Cy5-labeled particles by combining confocal microscopy and atomic force microscopy (AFM). We then developed a robust approach that integrates single-particle fluorescence imaging with 3D deconvolution and isosurface rendering to quantitate viral distribution and trafficking in human cells as well as animal tissues at the single-particle level. Using this quantitative method, we uncovered an as yet uncharacterized rate-limiting step during viral cell entry, while delineating nuclear accumulation of virions during the first 8 hours postinfection. Further, our studies revealed for the first time that following intramuscular injection, AAV spread progressively across muscle tissues through endomysium between myofibers instead of traversing through target cells. Such 3D resolution and quantitative dissection of vector-host interactions at the subcellular level should significantly improve our ability to resolve trafficking mechanisms of gene-delivery particles and facilitate the development of enhanced viral vectors.

The relationship studies between the profiling of blood biomarker and the CT imaging characteristics on coronary atherosclerosis

Background and ObjectiveStudies showed that the metabolic disorder of lipid and inflammatory factor in blood might lead to the injury of endothelium, and then generate artherosclerosis gradually. It is difficult...

Getting to the Heart of Things in the Field of Cardiovascular Gene Therapy

Getting to the Heart of Things in the Field of Cardiovascular Gene Therapy

Progress and prospects: hurdles to cardiovascular gene therapy clinical trials

Several gene therapy approaches have been designed for the treatment of cardiovascular diseases. A positive finding is that the safety of cardiovascular gene therapy has been excellent even in long-term follow-up. However, several hurdles to this field are still present. A major disappointing feature of the trials is that while preclinical and uncontrolled phase-I gene therapy trials have been positive, none of the randomized controlled phase-II/III cardiovascular gene therapy trials have shown clinically relevant positive effects. Low gene transfer efficiency seems to be associated with several trials. A sophisticated efficient delivery method for cardiovascular applications is still lacking and only low concentrations of the gene product are produced in the target tissues. Only a few gene therapy vectors can be produced in large scale. In addition, inflammatory reactions against vectors and inability to regulate gene expression are still present. Furthermore, a strong placebo effect is affecting the results in gene therapy trials, and long-term trials have become more difficult to conduct because of the multiplicity of therapies applied simultaneously on the patients. This review summarizes advances and obstacles of current cardiovascular clinical gene therapy trials.

Association of genomic loci from a cardiovascular gene SNP array with fibrinogen levels in European Americans and African-Americans from six cohort studies: the Candidate Gene Association Resource (CARe)

AbstractSeveral common genomic loci, involving various immunity- and metabolism-related genes, have been associated with plasma fibrinogen in European Americans (EAs). The genetic determinants of fibrinogen in African Americans (AAs) are poorly characterized. Using a vascular gene-centric array in 23 634 EA and 6657 AA participants from 6 studies comprising the Candidate Gene Association Resource project, we examined the association of 47 539 common and lower frequency variants with fibrinogen concentration. We identified a rare Pro265Leu variant in FGB (rs6054) associated with lower fibrinogen. Common fibrinogen gene single nucleotide polymorphisms (FGB rs1800787 and FGG rs2066861) significantly associated with fibrinogen in EAs were prevalent in AAs and showed consistent associations. Several fibrinogen locus single nucleotide polymorphism associated with lower fibrinogen were exclusive to AAs; these include a newly reported association with FGA rs10050257. For IL6R, IL1RN, and NLRP3 inflammatory gene loci, associations with fibrinogen were concordant between EAs and AAs, but not at other loci (CPS1, PCCB, and SCL22A5-IRF1). The association of FGG rs2066861 with fibrinogen differed according to assay type used to measure fibrinogen. Further characterization of common and lower-frequency genetic variants that contribute to interpopulation differences in fibrinogen phenotype may help refine our understanding of the contribution of hemostasis and inflammation to atherothrombotic risk.

Study on cardiovascular diseases marker gene expression profile of familial aggregation hypertension

To explore the cardiovascular diseases marker gene expression profile of the familial aggregation hypertension patients,and to screen differentially expressed genes. The patients who had directly related family members for more than three generations suffering from hypertension were selected as experiment group, and healthy individuals as control group. Oligo GEArray gene chip technique was used to detect the expression of cardiovascular diseases marker gene in peripheral blood. The ratio of positive/negative standard value >2.0, or ≤0.5 and >0 was identified as differential gene. Compared with control group, there were 10 up-regulated differential genes in experiment group, composing genes involved in lipid metabolism, immune response-related molecules, cell adhesion molecules, extracellular molecules and coagulation, including apolipoprotein E (ApoE), epithelial V-like antigen-1 (EVA-1), interferon-γ (IFN-γ), interleukin-1β (IL-1β), IL-8, integrin-β1 (ITGB-1), matrix metalloproteinase-9 (MMP-9), nuclear factor-ΚB (NF-ΚB), platelet endothelial cell adhesion molecule-1 (PECAM-1), selectin-P (SEL-P). There were 3 down-regulated genes, including coagulation factors-III (F-III), lectin-like oxidized low density lipoprotein receptor-1 (LOX-1), and serine protease inhibitor-1 (SERPINE-1). This study suggested that familial aggregation hypertension related to a variety of gene markers of cardiovascular disease, especially elements concerning coagulation and extracellular protease inhibitor-related genes.

Chondro/osteoblastic and cardiovascular gene modulation in human artery smooth muscle cells that calcify in the presence of phosphate and calcitriol or paricalcitol

Vitamin D sterol administration, a traditional treatment for secondary hyperparathyroidism, may increase serum calcium and phosphorus, and has been associated with increased vascular calcification (VC). In vitro studies suggest that in the presence of uremic concentrations of phosphorus, vitamin D sterols regulate gene expression associated with trans-differentiation of smooth muscle cells (SMCs) to a chondro/osteoblastic cell type. This study examined effects of vitamin D sterols on gene expression profiles associated with phosphate-enhanced human coronary artery SMC (CASMC) calcification. Cultured CASMCs were exposed to phosphate-containing differentiation medium (DM) with and without calcitriol, paricalcitol, or the calcimimetic R-568 (10−11–10−7 M) for 7 days. Calcification of CASMCs, determined using colorimetry following acid extraction, was dose dependently increased (1.6- to 1.9-fold) by vitamin D sterols + DM. In contrast, R-568 did not increase calcification. Microarray analysis demonstrated that, compared with DM, calcitriol (10−8 M) + DM or paricalcitol (10−8 M) + DM similarly and significantly (P < 0.05) regulated genes of various pathways including: metabolism, CYP24A1; mineralization, ENPP1; apoptosis, GIP3; osteo/chondrogenesis, OPG, TGFB2, Dkk1, BMP4, BMP6; cardiovascular, HGF, DSP1, TNC; cell cycle, MAPK13; and ion channels, SLC22A3 KCNK3. R-568 had no effect on CASMC gene expression. Thus, SMC calcification observed in response to vitamin D sterol + DM may be partially mediated through targeting mineralization, apoptotic, osteo/chondrocytic, and cardiovascular pathway genes, although some gene changes may protect against calcification. Further studies to determine precise roles of these genes in development of, or protection against VC and cardiovascular disease are required. J. Cell. Biochem. 111: 911–921, 2010. © 2010 Wiley-Liss, Inc.

Prospects of increasing the effectiveness of cardio-vascular gene and cell therapy: genetically modified cells

Prospects of increasing the effectiveness of cardio-vascular gene and cell therapy: genetically modified cells

Development of Viral Vectors for Use in Cardiovascular Gene Therapy

Cardiovascular disease represents the most common cause of mortality in the developed world but, despite two decades of promising pre-clinical research and numerous clinical trials, cardiovascular gene transfer has so far failed to demonstrate convincing benefits in the clinical setting. In this review we discuss the various targets which may be suitable for cardiovascular gene therapy and the viral vectors which have to date shown the most potential for clinical use. We conclude with a summary of the current state of clinical cardiovascular gene therapy and the key trials which are ongoing.

Selective Effects of Intrinsic A2AAR Activity on Cardiac and Coronary Injuries with LPS Challenge

We assessed the impact of A2A adenosine receptor (A2AAR) knockout (KO) on LPS-triggered cardiovascular injuries, inflammation, gene expression and mortality. LPS precipitated cardiac injury, with 7-fold elevations in serum cardiac troponin I (cTnI) and 25–35% reductions in ventricular contractility. Coronary dysfunction was evident as a 20% reduction in reactive hyperaemic flows. A2AAR KO augmented cTnI release 3-fold without modifying ventricular dysfunction. Coronary effects of LPS and A2AAR KO were identical, and LPS no longer modified hyperaemia in A2AAR KO hearts.

Local gene delivery via endovascular stents coated with dodecylated chitosan&amp;ndash;plasmid DNA nanoparticles

Development of efficacious therapeutic strategies to prevent and inhibit the occurrences of restenosis after percutaneous transluminal coronary angioplasty is critical for the treatment of cardiovascular diseases. In this study, the feasibility and efficiency of stents coated with dodecylated chitosan–plasmid DNA nanoparticles (DCDNPs) were evaluated as scaffolds for localized and prolonged delivery of reporter genes into the diseased blood vessel wall. Dodecylated chitosan–plasmid DNA complexes formed stable positive charged nanospheres with mean diameter of approximately 90–180 nm and zeta potential of +28 ± 3 mV. As prepared DCDNPs were spray-coated on stents, a thin layer of dense DCDNPs was successfully distributed onto the metal struts of the endovascular stents as demonstrated by scanning electron microscopy. The DCDNP stents were characterized for the release kinetics of plasmid DNA, and further evaluated for gene delivery and expression both in vitro and in vivo. In cell culture, DCDNP stents containing plasmid EGFP-C1 exhibited high level of GFP expression in cells grown on the stent surface and along the adjacent area. In animal studies, reporter gene activity was observed in the region of the artery in contact with the DCDNP stents, but not in adjacent arterial segments or distal organs. The DCDNP stent provides a very promising strategy for cardiovascular gene therapy.

Cardiac signaling genes exhibit unexpected sequence diversity in sporadic cardiomyopathy, revealing HSPB7 polymorphisms associated with disease.

Sporadic heart failure is thought to have a genetic component, but the contributing genetic events are poorly defined. Here, we used ultra-high-throughput resequencing of pooled DNAs to identify SNPs in 4 biologically relevant cardiac signaling genes, and then examined the association between allelic variants and incidence of sporadic heart failure in 2 large Caucasian populations. Resequencing of DNA pools, each containing DNA from approximately 100 individuals, was rapid, accurate, and highly sensitive for identifying common and rare SNPs; it also had striking advantages in time and cost efficiencies over individual resequencing using conventional Sanger methods. In 2,606 individuals examined, we identified a total of 129 separate SNPs in the 4 cardiac signaling genes, including 23 nonsynonymous SNPs that we believe to be novel. Comparison of allele frequencies between 625 Caucasian nonaffected controls and 1,117 Caucasian individuals with systolic heart failure revealed 12 SNPs in the cardiovascular heat shock protein gene HSPB7 with greater proportional representation in the systolic heart failure group; all 12 SNPs were confirmed in an independent replication study. These SNPs were found to be in tight linkage disequilibrium, likely reflecting a single genetic event, but none altered amino acid sequence. These results establish the power and applicability of pooled resequencing for comparative SNP association analysis of target subgenomes in large populations and identify an association between multiple HSPB7 polymorphisms and heart failure.

Modification of cardiovascular ion channels by gene therapy

Delivery of genes to the heart and vasculature for therapeutic purposes is an exciting strategy that is approaching clinical reality. Abnormalities of expression or function of ion channels is central to many cardiovascular diseases and gene delivery to modify ion channels is an appealing alternative to traditional therapy with small-molecule drugs. Potential therapeutic targets include hypertrophy and heart failure, atrioventricular node modification in atrial fibrillation, ventricular tachycardia and hypertension. Numerous approaches for gene delivery are under development, including use of tissue-specific promoters in viral vectors. For other applications, such as development of biological pacemakers, cells can be transduced with pacemaker genes in vitro, and then the cells implanted within the heart. There are short-term hurdles to therapeutic gene delivery to modify cardiovascular ion channels, but in the intermediate and longer term, the outlook is promising.

Biomedicinal implications of high-density lipoprotein: its composition, structure, functions, and clinical applications

High-density lipoprotein (HDL) is a proven biomarker for the monitoring of changes in antioxidant and anti-inflammation capability of body fluids. The beneficial virtues of HDL are highly dependent on its lipids and protein compositions, and their ratios. In normal state, the HDL particle is enriched with lipids and several HDL-associated enzymes, which are responsible for its antioxidant activity. Lower HDL-cholesterol levels (40 mg/dL) have been recognized as an independent risk factor for coronary artery disease, as well as being a known component of metabolic syndrome. Functional and structural changes of HDL have been recognized as factors pivotal to the evaluation of HDL-quality. In this review, I have elected to focus on the functional and structural correlations of HDL and the roles of HDL-associated apolipoproteins and enzymes. Recent clinical applications of HDL have also been reviewed, particularly the therapeutic targeting of HDL metabolism and reconstituted HDL; these techniques represent promising emerging strategies for the treatment of cardiovascular disease, for drug or gene therapy.

Common Variants in the ATP-binding Cassette Transporter 1 Gene with Decreased HDL-Cholesterol Levels and Coronary Artery Disease

Our aim was to determine whether the common variants within the coding sequence of ABCA1 gene affects low plasma high-density lipoprotein cholesterol (HDL-C) levels in Turkish patients with coronary artery disease (CAD). The study group was composed of 552 CAD patients, of which 251 had HDL-C levels < or =40 mg/dL, and 301 had HDL-C levels >40 mg/dL. PCR-RFLP was used to determine the A2589G and G3456C DNA polymorphisms of the ABCA1 gene. The study group was analyzed for potential clinical predictors of low HDL-C. The GG variant of the ABCA1 gene A2589G polymorphism was found in 3.6% patients within the HDL-C < or =40 mg/dL group and in 4% of HDL-C levels >40 mg/dL group. Frequency distributions of the A2589G genotypes were not found to differ significantly among groups. The CC genotype of the G3456C polymorphism was found in 6.8% of HDL-C < or =40 mg/dL group and in 11.6% individuals of the HDL-C levels >40 mg/dL group. Frequency distributions of the G3456G genotypes were not significantly different among groups. The A2589G genotypes were not found to be effective over the analyzed lipid parameters. Among G3456C genotypes, in CAD patients with HDL-C < or =40 mg/dL the low-density lipoprotein (LDL-C) levels were elevated, whereas HDL-C levels decreased in CC genotype carriers compared to GG and GC. No significant association was found between cardiovascular endpoints and ABCA1 gene A2589G and G3456C genotypes in this study population.

Abstract 2882: Directed Evolution of Cardiac Specific Adeno-Associated Vector Variants

Adeno-associated vectors (AAV) have gained popularity in cardiovascular gene transfer because of their distinct characteristics: long-term expression, minimal immune response and strong tropism to cardiac tissue for specific serotypes (such as AAV9). However AAVs have certain limitations: Neutralizing antibodies in 40% of humans for each AAV serotype and non-specificity of the AAV serotypes to various organs. Chimeric viruses composed of capsid proteins of different serotypes, show distinct transduction profiles. To identify hybrid viruses that can selectively transduce cardiomyocytes in vivo, we generated a library of diverse AAV variants, obtained by DNA shuffling, with an enrichment of cardiotropic AAV variants, called biological nanoparticles (BNPs). We selected five BNPs from these experiments: BNP 108, 109, 111, 689, and 693. We then injected these different BNPs using GFP as a marker gene under the control of CMV along with AAV9 into rats (3 in each group and each time point) through their tail vein at a concentration of 1011 vg (viral genomes). We sacrificed the animals at one and four weeks and examined expression in the heart, liver, lung, kidneys, and aorta. We found that at 1 week, BNP 108 and 109 had the best expression in the heart (61±12% of the myocytes with green fluorescence) while BNP 111 and AAV9 had strong cardiac expression at 4 weeks (93±11% and 79±12% of the myocytes with green fluorescence). None of the BNPs showed expression in the liver, lung, kidneys, and aorta, while AAV9 demonstrated widespread expression in all these tissues. Transcoronary injection of BNP111 at a concentration of 1012 vg demonstrated the efficiency of BNP in transducing myocardium of large animals. We also found that all the BNPs are resistant to preexisting neutralizing antibodies against parent serotypes. These results show that directed evolution of AAV variants can yield BNPs that are highly cardiotropic and highly efficient of transducing cardiac tissue without infecting other organs and having resistance to preexisting neutralizing antibodies against parent serotypes. These BNPs may become very useful for clinical applications.

Short Hairpin RNA Interference Therapy for Ischemic Heart Disease

During hypoxia, upregulation of hypoxia inducible factor-1 alpha transcriptional factor can activate several downstream angiogenic genes. However, hypoxia inducible factor-1 alpha is naturally degraded by prolyl hydroxylase-2 (PHD2) protein. Here we hypothesize that short hairpin RNA (shRNA) interference therapy targeting PHD2 can be used for treatment of myocardial ischemia and this process can be followed noninvasively by molecular imaging. PHD2 was cloned from mouse embryonic stem cells by comparing the homolog gene in human and rat. The best candidate shRNA sequence for inhibiting PHD2 was inserted into the pSuper vector driven by the H1 promoter followed by a separate hypoxia response element-incorporated promoter driving a firefly luciferase reporter gene. This construct was used to transfect mouse C2C12 myoblast cell line for in vitro confirmation. Compared with the control short hairpin scramble (shScramble) as control, inhibition of PHD2 increased levels of hypoxia inducible factor-1 alpha protein and several downstream angiogenic genes by >30% (P<0.01). Afterward, shRNA targeting PHD2 (shPHD2) plasmid was injected intramyocardially following ligation of left anterior descending artery in mice. Animals were randomized into shPHD2 experimental group (n=25) versus shScramble control group (n=20). Bioluminescence imaging detected plasmid-mediated transgene expression for 4 to 5 weeks. Echocardiography showed the shPHD2 group had improved fractional shortening compared with the shScramble group at Week 4 (33.7%+/-1.9% versus 28.4%+/-2.8%; P<0.05). Postmortem analysis showed increased presence of small capillaries and venules in the infarcted zones by CD31 staining. Finally, Western blot analysis of explanted hearts also confirmed that animals treated with shPHD2 had significantly higher levels of hypoxia inducible factor-1 alpha protein. This is the first study to image the biological role of shRNA therapy for improving cardiac function. Inhibition of PHD2 by shRNA led to significant improvement in angiogenesis and contractility by in vitro and in vivo experiments. With further validation, the combination of shRNA therapy and molecular imaging can be used to track novel cardiovascular gene therapy applications in the future.

Gene therapy for coronary and peripheral artery disease

Background: Coronary and peripheral artery diseases are highly prevalent diseases, which are characterised by an unmet medical need in the more advanced stages of disease. These comprise the need for vessel regeneration using therapeutic angiogenic gene therapy as well as the prevention of restenosis post-angioplasty using local gene therapy. Both problems have been addressed by extensive research. Objective: Therefore, this article reviews the patents for therapeutic strategies using gene therapy for the prevention of restenosis and induction of therapeutic angiogenesis in the years 1994 – 2008. Methods: Current publications, websites and patents of a number of potentially suitable gene constructs are reviewed. Conclusion: Cardiovascular gene therapy, particularly in therapeutic angiogenesis, has quietly made its way to the first Phase III approval gene therapy trial. There are chances for more gene constructs to reach this stage.

Percutaneous transplantation of genetically-modified autologous fibro-blasts in the rabbit femoral artery: a novel approach for cardiovascular gene therapy

Percutaneous transplantation of genetically-modified autologous fibro-blasts in the rabbit femoral artery: a novel approach for cardiovascular gene therapy