ABSTRACT: Expression profile of human lymphatic endothelial cells under static or oscillatory shear stress conditions in the presence or absence of FOXC2
Project description:Lymphatic valves are specialized units regularly distributed along collecting vessels that allow unidirectional forward propulsion of the lymph, and its efficient transport from tissues to the bloodstream. Lymphatic endothelial cells that cover lymphatic valve sinuses are subjected to complex flow patterns, due to recirculation of the lymph during the collecting vessel pumping cycle. They also express high levels of FOXC2 transcription factor. We used microarrays to study the transcriptional networks controlled by FOXC2 in human lymphatic endothelial cells subjected to oscillatory shear stress or cultured under static conditions. Human lymphatic endothelial cells were transfected with control or FOXC2 siRNAs and subjected to 24-hour oscillatory shear stress (1 dyn/cm2; 1/4 Hz) or kept under static conditions as a control. RNA were amplified and hybridized on Affymetrix Human Gene 1.0 ST Arrays. The experiment was run twice independently, using each time a different siRNA to knockdown FOXC2, as previously described (Sabine et al, 2012, Dev Cell).
Project description:Lymphatic valves are specialized units regularly distributed along collecting vessels that allow unidirectional forward propulsion of the lymph, and its efficient transport from tissues to the bloodstream. Lymphatic endothelial cells that cover lymphatic valve sinuses are subjected to complex flow patterns, due to recirculation of the lymph during the collecting vessel pumping cycle. They also express high levels of FOXC2 transcription factor. We used microarrays to study the transcriptional networks controlled by FOXC2 in human lymphatic endothelial cells subjected to oscillatory shear stress or cultured under static conditions.
Project description:To profile shear stress-regulated endothelial transcriptomes, we performed RNA-seq with HUVECs subjected to different shear flow conditions, including atheroprotective pulsatile shear (PS, 12±4 dyn/cm2) and atheroprone oscillatory shear (OS, 0.5±4 dyn/cm2), or kept as static control (ST) for four time periods (1, 4, 12 and 24 hours)
Project description:Laminar shear stress due to constant blood flow is known to play a critical role in maintaining vascular health. In contrast, endothelial cell senescence appears to be closely associated with the incidence of vascular disorder. In an attempt to identify functional biomarkers for age-related vascular health/disease, the present study investigated differential gene expression of young and senescent human umbilical vein endothelial cells (HUVECs) under static and laminar shear stress. We used a cDNA microarray method to compare gene expression profiles of young and senescent HUVECs under static and laminar shear stress conditions. Experiment Overall Design: Senescent cells were prepared by continuous subculture in vitro, and a cone-and-plate device was used to impose laminar shear stress onto cells. Young and senescent cells were exposed to laminar shear stress or maintained under static conditions. Total mRNA was extracted and gene expression profiles were analyzed by cDNA microarray.
Project description:While variations in gene transcription networks in models of atherosclerosis have been reported, the underlying changes in the chromatin landscape induced by pro-atherogenic stimuli remain elusive. In the present study, we report changes in chromatin regulatory elements that mediate transcriptional control upon the application of oscillatory shear stress of ±3 dyn/cm2 in primary cultured human umbilical vein endothelial cells (HUVECs) at 6 h time point of oscillatory shear stress stimulation compared to static condition.
Project description:The goal of this study was to find longitudinal transcriptional response of Human Umbilical Vein Endothelial Cells (HUVECs) to pulsatile shear (PS) and oscillatory shear (OS). PS is associated with an atheroprotective endothelial phenotype, while OS is associated with an atheroprone endothelial phenotype. Using RNASeq method (single-ended 50-bp sequencing on Illumina Hi-seq 2000 instrument), we measured the transcriptional response at 10 time-points (1, 2, 3, 4, 6, 9, 12, 16, 20, 24 hr) under PS and OS conditions. Low flow scenario was used as static condition. Two replicates were used for each condition/time-point. Results: Through combining the temporal data on differentially expressed transcription factors and their targets with existing knowledge on relevant functional pathways, we infer the causal relationships between disparate endothelial functions through common transcriptional regulation mechanisms. Our study presents the first comprehensive temporally longitudinal experimental study and mechanistic model of shear stress response. By comparing the relative endothelial expressions of genes between OS and PS, we provide novel insights and an integrated perspective into endothelial cell function in response to differential shear.
Project description:This data set reveals the changes of histone modifications and chromatin accessibility in human umbilical vein endothelial cells (HUVECs) under atheroprotective pulsatile shear (PS), atheroprone oscillatory shear (OS), or with KLF4 overexpression. Using ChIP-Seq, we defined the H3K27ac and H3K4me1 enrichment under PS and OS conditions. Using ATAC-seq, we identified the chromatin accessibility under KLF4 overexpression.
Project description:This data set reveals the changes of histone modifications and chromatin accessibility in human umbilical vein endothelial cells (HUVECs) under atheroprotective pulsatile shear (PS), atheroprone oscillatory shear (OS), or with KLF4 overexpression. Using ChIP-Seq, we defined the H3K27ac and H3K4me1 enrichment under PS and OS conditions. Using ATAC-seq, we identified the chromatin accessibility under KLF4 overexpression.
Project description:Many studies have characterized the results of shear stress changes on cultured endothelial cells in different bioreactor systems. However it is still unclear how an invasive intervention like stent procedure may influence the transcriptional response of endothelium. To study the simultaneous effects of shear stress changes and stent application on endothelial gene expression, we have used an experimental apparatus of laminar flow bioreactor (LFB) system with human cultured endothelial cells exposed or not exposed to stent procedure with different flow conditions. Microarray analysis was evaluated in each experimental protocol. HUVECs (2nd and 5th passage) covered on Thermanox slides were submitted to static, low and physiological (0, 1, 5 and 10 dyne/cm2) shear stress in absence (AS) or presence (PS) of stent in LFB system for 24h. Affymetryx analysis has been performed in duplicate by Consortium for Genomic Technologies (Cogentech; Milan, Italy)
Project description:Laminar shear stress due to constant blood flow is known to play a critical role in maintaining vascular health. In contrast, endothelial cell senescence appears to be closely associated with the incidence of vascular disorder. In an attempt to identify functional biomarkers for age-related vascular health/disease, the present study investigated differential gene expression of young and senescent human umbilical vein endothelial cells (HUVECs) under static and laminar shear stress. We used a cDNA microarray method to compare gene expression profiles of young and senescent HUVECs under static and laminar shear stress conditions. Keywords: stress response, age state analysis
