Project description:Cyclic mechanical loads applied to the skeleton increase bone formation. Dynamic fluid flow is a potent anabolic stimulus for cultured osteoblasts. In this study, gene profiles involved in mediating the anabolic response of MC3T3 osteoblasts to dynamic fluid flow are investigated. MC3T3 osteoblast RNA was harvested 30-minutes and 1-hour post-stimulation respectively as experimental samples for comparison to the control group without dynamic fluid flow.
Project description:Cyclic mechanical loads applied to the skeleton increase bone formation. Dynamic fluid flow is a potent anabolic stimulus for cultured osteoblasts. In this study, gene profiles involved in mediating the anabolic response of MC3T3 osteoblasts to dynamic fluid flow are investigated.
Project description:Osteoblasts are responsive to shear stress. We investigated the effect of of laminar fluid flow (LFF) on osteoblast-like MC3T3-E1 cells at two timepoints. We used microarray analysis to detail the global gene expression of MC3T3-E1 cells in response to 1 hour of laminar fluid flow directly and 4 hours after treatment.
Project description:All living cells are constantly exposed to a number of physical forces. The study aims to investigate the response of fibroblasts to dynamic mechanical forces.This experiment captures the expression data obtained by performing microarray based analysis on dermal fibroblasts subjected to 75 and 150 µl/min fluid flow rate.
Project description:RNA-seq technology was used to reveal the transcriptome changes of tubular epithelia in response to fluid flow and determine the role of primary cilia in this process. Many fluid flow-sensitive genes were identified, among which are those regulated by primary cilia sensing of fluid flow. These genes were further validated by RT-qPCR.
Project description:Renal epithelial cells are exposed to mechanical forces due to flow-induced shear stress within the nephrons. We applied RNA sequencing to get a comprehensive overview of fluid-shear regulated genes and pathways in the immortalized renal proximal tubular epithelial cell line. Cells were exposed to laminar fluid shear stress (1.9 dyn/cm2) in a cone-plate device and compared to static controls.
Project description:Pkd1-/- renal epithelial cells are exposed to mechanical forces due to flow-induced shear stress within the nephrons. We applied RNA sequencing to get a comprehensive overview of fluid-shear regulated genes and pathways in the immortalized Pkd1-/- renal proximal tubular epithelial cell line. Cells were exposed to laminar fluid shear stress (1.9 dyn/cm2) in a cone-plate device and compared to static controls.
Project description:The highly negatively charged endothelial surface glycocalyx (ESG) functions as mechano-sensor detecting shear forces generated by the blood flow on the luminal side of brain endothelial cells (ECs) and contributes to the physical barrier of the blood-brain barrier (BBB). Despite the importance of ESG in the regulation of BBB permeability in physiological conditions and in diseases, this is an underresearched area. Microfluidic lab-on-a-chip (LOC) devices allow the study of BBB properties in dynamic conditions. We studied a BBB model, human endothelial cells derived from hematopoetic stem cells in co-culture with brain pericytes, in an LOC device to understand the role of fluid flow in the regulation of ESG-related genes and surface charge. The MACE gene sequencing study showed differentially expressed core protein genes of the ESG after fluid flow, as well as enriched pathways for the extracellular matrix molecules. We observed increased barrier properties, a higher intensity glycocalyx staining and a more negative surface charge of human brain ECs in dynamic conditions. Our study is the first to provide data on ESG of human ECs in an LOC device under dynamic conditions and confirm the importance of fluid flow for BBB culture models.
Project description:Objective: Shear forces play a key role in the maintenance of vessel wall integrity. Current understanding regarding shear-dependent gene expression is mainly based on in vitro or in vivo observations with experimentally deranged shear, hence reflecting acute molecular events in relation to flow. Our objective was to combine computational fluid dynamic (CFD) simulations with global microarray analysis to study flow-dependent vessel wall biology in portions of the entire aorta under physiological conditions. Methods and Results: Animal-specific WSS magnitude and vector direction were estimated using CFD based on aortic geometry and flow information acquired by MRI. Two distinct flow pattern regions were identified in the normal rat aorta; the distal part of the inner curvature being exposed to low WSS and a non-uniform vector direction, and a region along the outer curvature being subjected to markedly higher levels of WSS and a uniform vector direction. Microarray analysis identified numerous novel mechanosensitive genes, including Hand2, trpc4 and slain2, and confirmed well-known ones, such as klf2 and BMP4. Three genes were further validated for protein , including Hand2, which showed higher expression in the endothelium in regions exposed to disturbed flow. Gene ontology analysis revealed an over-representation of genes involved in transcriptional regulation.
Project description:Amniotic fluid stem cells (AFSCs) are of interest in regenerative medicine as a non-controversial and potentially 'abundant' source of stem cells. Progress has been made in understanding amniotic fluid stem cell biology, and amniotic fluid-derived cells have been induced to form neurons, osteoblasts, muscle cells, and others. Our study evaluates change in the genome-wide expression profile of amniotic fluid stem cells during in-vitro culture, using Affymetrix U133 Plus 2.0 microarray chips. We found that only 3.08% of gene probes were differentially expressed from early to late passage of AFSC culture. The differentially expressed genes were related to biological processes or cellular function - including transcription factors, protein kinases, and cytokines/growth factors. Other gene-sets of interest were oncogenes and tumor suppressor genes, which were a very small number of genes. We further analyzed the gene sets of interest using NIH DAVID and GSEA bioinformatics databases for gene annotations analysis. Applying false discovery rate correction, there was no significant difference in the genome-wide expression profiling between early and late passage. AFSCs maintain their genome-wide expression profile during in-vitro culture. Amniotic fluid-derived c-kit-positive cells were maintained in stem cell culture and genome-wide expression changes were studied and compared between early passage and late passage in culture.