Project description:Patients with bicuspid aortic valve (BAV) have increased risk of thoracic ascending aortic aneurysm (AscAA) and dissection compared to those with a normal tricuspid aortic valve (TAV). The present study was undertaken to evaluate whether differences in gene expression exist in aortas from BAV and TAV patients with AscAA. Experiment Overall Design: Aneurysmal tissue of ascending aorta was collected from 13 patients with bicuspid aortic valve (BAV) and 12 patients with tricuspid aortic valve (TAV). Patients were selected on the basis of aortic diameter, age and other disease conditions. Patients with giant cell aortitis, cardiovascular abnormalities, inherited connective tissue disorders such as Marfan and Ehlers-Danlos syndrome were excluded from the study. RNA was extracted using Invitrogen RNA extraction kit and shown to be of adequate quality before application to Affymetrix microarray U133A gene chips probing for over 16,000 genes per chip. Two different methods of data analysis were performed: a linear model and GeneSpring.
Project description:Bicuspid aortic valve is well known as a risk factor of dilation of ascending aorta. But the mechanisms of dialation are unknown. Morever, patients with bicuspid aortic valve tend to be aortic valve disease at younger age. After aortic valve surgery, if ascending aorta is dilated, the patient must be performed re-operation. For that reason, surgery for aortic root or ascending aorta is recommended to patient with bicuspid aortic valve with dilated ascending aorta. We thought that abnormality of cell cycle of the structure protein participated in ascending aorta dilation of patient with bicuspid aortic valve. We resected the wall of the ascending aota from patient undergoing aortic valve replacement for aortic valve stenosis during operation, and performed immunohistochemical staining for akt. Anti Akt antibodys were stained much on aortic media with bicuspoed aortic valve. Akt is a protein that is involved in mTOR / PI3K, and modulate the cell differenciation and proliferation. Further, the same samples were analyzed using a microarray method. On bicuspid aortic valve patients, the expression of TSC2 is reduced, and GβL is increased. TSC2 inhibit this pathway, and MLST8 activate this pathway. In the ascending aorta of BAV patients, PI3K / mTOR system is considered to be activated. When this pathway is activated, cell proliferation and cytodifferentiation are promoted abnormally,
Project description:Genome wide DNA methylation profiling of ascending aorta tissue samples from normal, aortic dissection and bicuspid aortic valve patients with aortic dilation. The Illumina Infinium 450k Human DNA methylation Beadchip was used to obtain DNA methylation profiles across more than 450,000 CpGs in ascending aorta samples. Samples included 6 normal donors, 12 patients with aortic dissection and 6 patients with bicuspid aortic valve and dilated aorta.
Project description:Patients with bicuspid aortic valve (BAV) have increased risk of thoracic ascending aortic aneurysm (AscAA) and dissection compared to those with a normal tricuspid aortic valve (TAV). The present study was undertaken to evaluate whether differences in gene expression exist in aortas from BAV and TAV patients with AscAA. Keywords: disease state analysis
Project description:The molecular basis of aortic valve degeneration (AVD) is unclear. The extracellular matrix (ECM) of the valve is in dynamic reciprocity with its surrounding microenvironment and contains molecular traits of the pathophysiological processes. We compared abundances of ECM proteins from excised valve tissues of 88 patients with isolated AVD of normal tricuspid (TAV) and congenital bicuspid aortic valves (BAV) by employing a new method for protein preparation and quantitative mass-spectrometry analysis.
Project description:The objective of this study was to identify genes differentially expressed between calcified bicuspid aortic valves (BAV) and tricuspid valves with (TAVc) and without (TAVn) aortic valve stenosis. Ten human BAV and nine TAVc were collected from male who underwent primary aortic valve replacement. Eight TAVn were obtained from male who underwent heart transplantation. mRNA levels were measured using Illumina HumanHT-12 v4 Expression BeadChip and compared between valve groups.
Project description:Conducted proteomics on samples from patients with aortic aneurysm and from non-dilated controls. Furthermore, we investigated both patients with bicuspid aortic valves (BAV) and also the more normal tricuspid aortic valves (TAV). The aim was to elucidate the molecular mechanisms behind the higher propensity of BAV patients to develop aorta dilation and consequent aortic aneurysm.
Project description:Bicuspid aortic valve (BAV) is a common congenital cardiac anomaly, with an estimated incidence of 1-2%. It is responsible for the greatest burden of aortic valve disease in patients younger than 70 years in North America. We performed microRNA profiling in end-stage valve leaflets with BAV and TAV. Patients undergoing elective aortic valve replacement for aortic stenosis at St. Michael’s Hospital, University of Toronto, between June 2010 and June 2011 were enrolled. Aortic valve leaflets were obtained intraoperatively from patients with congenital bicuspid (BAV; N=10) and tricuspid aortic valves (TAV; N=10) at the time of valve replacement. Leaflets were flash frozen in liquid nitrogen. MiRNA was isolated using the miRNeasy kit (Qiagen, Hilden, Germany) according to the manufacturer`s instructions. For miRNA microarray analysis, total RNA was directly labeled with biotin and hybridized to the GenoExplorer microRNA human array containing 1583 human miRNA probes (Genosensor, Tempe, AZ) and the fluorescent signals were then scanned using a GenePix 4000b Biochip. The average of 3 mean fluorescence signal intensities for each miRNA probe was normalized to that for tRNAmet. Precursor miRNAs detected at 2-fold greater than background were considered to be expressed. Data were analyzed with GenePix 5.0 software, provided by GenoSensor Corp.
Project description:BACKGROUND: The vast majority of thoracic aortic aneurysms (TAAs) are observed either together with a bicuspid aortic valve (BAV), a common congenital disorder, or in idiopathic cases such as patients with a normal tricuspid aortic valve (TAV). The main objective of our study was to identify shared and unique gene expression properties underlying the aortic dilation of BAV and TAV patients. METHODS AND RESULTS: Tissue biopsies for RNA and histological analyses were obtained from aorta of non-dilated (<40mm) and dilated (>45mm) aorta of BAV and TAV patients (in total 131 patients). Additional controls were from mammary artery of the same patients (n=88) and aorta from transplant donors (n=13). Gene expression profiles generated using Affymetrix Exon arrays were analyzed from controls and from aorta intima-media and adventitia of patients (in total 345 samples). 606 genes in aortic intima-media were found to be differentially expressed with dilation. Of these, only few (<4%) were differentially expressed in both BAV and TAV patients. Gene set enrichment analysis identified cell adhesion and extracellular region gene ontology sets as common features of TAA in BAV and TAV patients. The set of immune response genes was observed to be particularly overexpressed in aortic media of dilated TAV samples. CONCLUSION: The divergent gene expression profiles indicate fundamental differences in TAA etiology of BAV and TAV patients. Immune response activation solely in the aorta media of TAV patients suggests that inflammation is a causal factor of TAA in this patient group. Biobank of patient material. Each tissue sample is from a different patient as indicated by patient ID.
Project description:Purpose: The molecular mechanisms leading to premature development of aortic valve stenosis (AS) in individuals with a bicuspid aortic valve (BAV) are unknown. The objective of this study was to identify genes differentially expressed between calcified BAV and tricuspid valves with (TAVc) and without (TAVn) calcification using RNA sequencing (RNA-Seq). Methods: Ten human calcified BAV and nine TAVc were collected from men who underwent aortic valve replacement. Eight TAVn were obtained from men who underwent heart transplantation. mRNA levels were measured using the Illumina HiSeq 2000 system. Reads were aligned with TopHat. Cuffdiff, DESeq, edgeR, and SAMSeq were used to compare gene expression. Genes with adjusted P < 0.05 in the four methods were called differentially expressed. Pathway analysis was performed with IPA. Results: Two genes were up-regulated and none were down-regulated in BAV compared to TAVc. There were 462 genes up-regulated and 282 down-regulated in BAV compared to TAVn. Compared to TAVn, 329 genes were up- and 170 were down-regulated in TAVc. Conclusions: This is the first transcriptome study on calcified and normal aortic valves using RNA-Seq. BAV and TAVc have a highly similar expression profile. These results contribute to our molecular understanding of AS and the identification of new therapeutic targets that are urgently needed to prevent, slow the development or treat AS in patients with bicuspid and tricuspid valves.