Project description:This SuperSeries is composed of the following subset Series:; GSE13835: Smooth muscle cells in atherosclerosis-prone and resistant regions of the aorta of C57Bl/6 mice at age of 4 months; GSE13836: Smooth muscle cells in atherosclerosis-prone and resistant regions of the aorta of apoE-/- mice at age of 4 months Experiment Overall Design: Refer to individual Series
Project description:This study compared gene expression in smooth muscle cells (SMCs) in atherosclerosis-prone and atherosclerosis-resistant aorta segments in 4 months old apolipoprotein E-deficient (apoE-/-) mice before plaque development. In a parallel experiment, both regions were compared in young C57Bl/6 mice. Aortas of 3 male and 3 female ApoE-/- mice were isolated, perfused with triton X-100 to remove endothelial cells and divided in an atherosclerosis-prone region (AA: ascending aorta, aortic arch and proximal 2 mm of thoracic aorta) and a resistant region (TA: central thoracic aorta, i.e. 6 mm distal from the proximal 2 mm). Microarray analysis (VIB-MAF) of pooled total RNA showed differential expression (>2-fold difference) for 244 genes. Up- or downregulation in the AA was observed for 186 and 58 genes respectively. Differential expression of 6 genes was confirmed using real-time PCR. The 201 genes that showed exclusively differential expression in apoE-/- mice were related to processes involved in atherosclerosis, such as cell adhesion, proliferation, differentiation, motility and death, lipid metabolism and immune responses. Furthermore, the transcription profile of the AA was in accordance with a more synthetic SMC phenotype. These results point to an altered transcriptome in SMCs in the aorta of apoE-/- mice at the atherosclerosis-prone location before actual lesion development. This suggests that SMCs, in addition to endothelial cells, can facilitate plaque formation at predilection sites.
Project description:This study compared gene expression in smooth muscle cells (SMCs) in atherosclerosis-prone and atherosclerosis-resistant regions of the aorta of C57Bl/6 mice. In a parallel experiment, both regions were compared in young, plaque-free apolipoprotein E-deficient (apoE-/-) mice. Aortas of 3 male and 3 female C57Bl6 mice were isolated, perfused with triton X-100 to remove endothelial cells and divided in an atherosclerosis-prone region (AA: ascending aorta, aortic arch and proximal 2 mm of thoracic aorta) and an atherosclerosis-resistant region (TA: central thoracic aorta,i.e. 6 mm distal from the proximal 2mm of the thoracic aorta). Microarray analysis (VIB-MAF) of pooled total RNA showed differential expression (>2-fold difference) for 70 genes. Up- or downregulation in the AA was observed for 33 and 37 genes respectively. Differential expression of 3 genes (ATPase, Na+/K+ transporting, beta 1 polypeptide, sarcolipin and homeo box B7) was confirmed using real-time PCR. Twenty five genes showed exclusively differential expression in C57BL6 mice. Only 7 could be linked to specific processes: development (4) and cell growth (3). The other 18 genes were all involved in different processes. Among the 45 genes showing differential expression in C57Bl/6 as well as apoE-/- mice, most were related to development (13), cell growth (8) and transcription (10). These results point to an altered transcriptome in SMCs of the C57Bl/6 aorta at an atherosclerosis-prone location. This is in agreement with findings in endothelial cells in atherosclerosis-prone regions. It could be due to biomechanical differences, for instance in wall tension or shear stress, or the different embryological origin of SMCs in AA and TA.
Project description:This study compared gene expression in smooth muscle cells (SMCs) in atherosclerosis-prone and atherosclerosis-resistant aorta segments in 4 months old apolipoprotein E-deficient (apoE-/-) mice before plaque development. In a parallel experiment, both regions were compared in young C57Bl/6 mice. Aortas of 3 male and 3 female ApoE-/- mice were isolated, perfused with triton X-100 to remove endothelial cells and divided in an atherosclerosis-prone region (AA: ascending aorta, aortic arch and proximal 2 mm of thoracic aorta) and a resistant region (TA: central thoracic aorta, i.e. 6 mm distal from the proximal 2 mm). Microarray analysis (VIB-MAF) of pooled total RNA showed differential expression (>2-fold difference) for 244 genes. Up- or downregulation in the AA was observed for 186 and 58 genes respectively. Differential expression of 6 genes was confirmed using real-time PCR. The 201 genes that showed exclusively differential expression in apoE-/- mice were related to processes involved in atherosclerosis, such as cell adhesion, proliferation, differentiation, motility and death, lipid metabolism and immune responses. Furthermore, the transcription profile of the AA was in accordance with a more synthetic SMC phenotype. These results point to an altered transcriptome in SMCs in the aorta of apoE-/- mice at the atherosclerosis-prone location before actual lesion development. This suggests that SMCs, in addition to endothelial cells, can facilitate plaque formation at predilection sites. Experiment Overall Design: samples were hyrbidized in dye-swap.
Project description:This study compared gene expression in smooth muscle cells (SMCs) in atherosclerosis-prone and atherosclerosis-resistant regions of the aorta of C57Bl/6 mice. In a parallel experiment, both regions were compared in young, plaque-free apolipoprotein E-deficient (apoE-/-) mice. Aortas of 3 male and 3 female C57Bl6 mice were isolated, perfused with triton X-100 to remove endothelial cells and divided in an atherosclerosis-prone region (AA: ascending aorta, aortic arch and proximal 2 mm of thoracic aorta) and an atherosclerosis-resistant region (TA: central thoracic aorta,i.e. 6 mm distal from the proximal 2mm of the thoracic aorta). Microarray analysis (VIB-MAF) of pooled total RNA showed differential expression (>2-fold difference) for 70 genes. Up- or downregulation in the AA was observed for 33 and 37 genes respectively. Differential expression of 3 genes (ATPase, Na+/K+ transporting, beta 1 polypeptide, sarcolipin and homeo box B7) was confirmed using real-time PCR. Twenty five genes showed exclusively differential expression in C57BL6 mice. Only 7 could be linked to specific processes: development (4) and cell growth (3). The other 18 genes were all involved in different processes. Among the 45 genes showing differential expression in C57Bl/6 as well as apoE-/- mice, most were related to development (13), cell growth (8) and transcription (10). These results point to an altered transcriptome in SMCs of the C57Bl/6 aorta at an atherosclerosis-prone location. This is in agreement with findings in endothelial cells in atherosclerosis-prone regions. It could be due to biomechanical differences, for instance in wall tension or shear stress, or the different embryological origin of SMCs in AA and TA. Experiment Overall Design: Samples were hybridized in dye-swap design.
Project description:AimsCellular communication network factor 2 (CCN2) is a matricellular protein implicated in fibrotic diseases, with ongoing clinical trials evaluating anti-CCN2-based therapies. By uncovering CCN2 as abundantly expressed in non-diseased artery tissue, this study aimed to investigate the hypothesis that CCN2 plays a pivotal role in maintaining smooth muscle cell (SMC) phenotype and protection against atherosclerosis.Methods and resultsGlobal- and SMC-specific Ccn2 knockout mouse models were employed to demonstrate that Ccn2 deficiency leads to SMC de-differentiation, medial thickening, and aorta elongation under normolipidaemic conditions. Inducing hyperlipidaemia in both models resulted in severe aorta malformation and a 17-fold increase in atherosclerosis formation. Lipid-rich lesions developed at sites of the vasculature typically protected from atherosclerosis development by laminar blood flow, covering 90% of aortas and extending to other vessels, including coronary arteries. Evaluation at earlier time points revealed medial lipid accumulation as a lesion-initiating event. Fluorescently labelled LDL injection followed by confocal microscopy showed increased LDL retention in the medial layer of Ccn2 knockout aortas, likely attributed to marked proteoglycan enrichment of the medial extracellular matrix. Analyses leveraging data from the Athero-Express study cohort indicated the relevance of CCN2 in established human lesions, as CCN2 correlated with SMC marker transcripts across 654 transcriptomically profiled carotid plaques. These findings were substantiated through in situ hybridization showing CCN2 expression predominantly in the fibrous cap.ConclusionThis study identifies CCN2 as a major constituent of the normal artery wall, critical in regulating SMC differentiation and aorta integrity and possessing a protective role against atherosclerosis development. These findings underscore the need for further investigation into the potential effects of anti-CCN2-based therapies on the vasculature.