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Jones, E. A. V.

Publications and source records attributed to Jones, E. A. V..

3 recordsLinked to original sources

Matrix stiffness shifts the endothelial shear stress set point for angiogenic activation

AimsEndothelial cells (ECs) are simultaneously exposed to wall shear stress (SS) from blood flow and substrate stiffness (SFN) from the extracellular matrix, yet how these cues are integrated to shape endothelial behavior remains incompletely understood. We applied an unbiased transcriptomics strategy to define how SS and substrate SFN jointly encode endothelial state transitions and determine angiogenic activation thresholds. Methods and ResultsWe generated a factorial RNA-Seq dataset of human ECs exposed to 14 combinations of SS (0-40 dynes/cm{superscript 2}) and SFN (1-100 kPa). DESeq2 with likelihood ratio testing identified genes whose expression was significantly associated with SS, SFN, or their interaction. SS was the dominant driver of global transcriptional variation and elicited non-linear transcriptional responses, whereas substrate SFN had a smaller direct effect but significantly modulated the endothelial response to flow. Interaction analyses identified gene programs associated with vascular remodeling, including angiogenesis and migration. Pathway-level analyses revealed that substrate SFN shifts the SS threshold at which angiogenic transcriptional programs become activated, indicating that SFN tunes the endothelial angiogenic set point rather than scaling the response magnitude. Moreover, activated states differed qualitatively across mechanical contexts, reflecting context-dependent reweighting of shared inflammatory, stress, and adaptive/remodeling programs. Finally, siRNA-mediated YAP1 knockdown confirmed its contribution to SS-SFN-dependent gene regulation. ConclusionThis study provides a systems-level experimental and bioinformatic framework for disentangling multifactorial mechanotransduction in ECs. Although SS predominates in shaping endothelial transcriptomes, substrate SFN critically modulates how ECs interpret flow by shifting the threshold for angiogenic transcriptional activation and reweighting downstream pathways. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=145 SRC="FIGDIR/small/740002v1_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@b615d7org.highwire.dtl.DTLVardef@54121dorg.highwire.dtl.DTLVardef@1715e4corg.highwire.dtl.DTLVardef@1e6018e_HPS_FORMAT_FIGEXP M_FIG C_FIG Translational PerspectiveBy systematically combining substrate stiffness and shear stress across physiological and pathological ranges, we provide a reference dataset for vascular mechanobiology. These data enable interpretation of endothelial responses across clinically relevant mechanical environments, including stiffness ranges in different organs (1- brain; 10-muscle or fibrotic liver; 100-aortic valves; kPa), shear stress ranges in different vascular beds (5-veins, 25-capillaries, 40-valves; dynes/cm2), and disease-associated changes such as matrix stiffening. Incorporating interactions between mechanical cues may improve the design of in vitro vascular models and enhance computational prediction of vascular remodeling.

cell biology↗

Vascular contribution to cognitive impairment in heart failure with preserved ejection fraction: TRPV4 and KLF2 as key mediators of neurovascular dysfunction in the ZSF1 model

Vascular cognitive impairment (VCI) shares major risk factors with heart failure with preserved ejection fraction (HFpEF), including obesity, diabetes and hypertension. Yet VCI research often relies on single-stimulus models, whereas patients experience combined risk factors. We therefore assessed cerebrovascular and cognitive phenotypes in an HFpEF model and investigated underlying mechanisms. Male Lean and Obese ZSF1 rats underwent longitudinal assessments of blood pressure, glucose, cardiac function, and behavioural performance. Cerebral blood flow and neurovascular coupling were assessed by laser speckle contrast imaging. White matter integrity, blood-brain barrier (BBB) permeability, and vascular density were analysed by (immuno)histochemistry. Cortical microvessels were isolated for transcriptomic profiling, and selected targets were validated using multiplex in-situ hybridization. Obese rats exhibited neurovascular uncoupling and impaired short- and long-term memory and spatial learning, accompanied by brain atrophy and reduced myelin. BBB permeability increased at 22-23 weeks and vascular density at 34-35 weeks in Obese vs Lean rats. Transcriptomic analysis of brain microvessels revealed altered processes related to angiogenesis, vasoreactivity, immune mechanisms and vascular remodelling, with consistent downregulation of Trpv4 and Klf2. Obese ZSF1 rats develop progressive neurovascular dysfunction associated with HFpEF onset and reduced Trpv4 and Klf2 expression in cerebral microvessels, two key vasoprotective genes.

neuroscience↗

Piezo1 channel activates ADAM10 sheddase to regulate Notch1 and gene expression

Mechanical force has emerged as a determinant of Notch signalling but the mechanisms of force sensing and coupling to Notch are unclear. Here we propose a role for Piezo1 channels, the recently identified mechanosensors of mammalian systems. Piezo1 channel opening in response to shear stress or a chemical agonist led to activation of a disintegrin and metalloproteinase domain-containing protein 10 (ADAM10), a Ca2+-regulated transmembrane sheddase that mediates S2 Notch1 cleavage. Consistent with this observation there was increased Notch1 intracellular domain (NICD) that depended on ADAM10 and the downstream S3 cleavage enzyme, {gamma}-secretase. Endothelial-specific disruption of Piezo1 in mice led to decreased Notch1-regulated gene expression in hepatic vasculature, consistent with prior evidence that Notch1 controls hepatic perfusion. The data suggest Piezo1 as a mechanism for coupling physiological force at the endothelium to ADAM10, Notch1, gene expression and vascular function.

cell biology↗