Dataset Information

Mechanical Stretch Increases Expression of CXCL1 in Liver Sinusoidal Endothelial Cells to Recruit Neutrophils, Generate Sinusoidal Microthombi, and Promote Portal Hypertension.

ABSTRACT: BACKGROUND & AIMS:Mechanical forces contribute to portal hypertension (PHTN) and fibrogenesis. We investigated the mechanisms by which forces are transduced by liver sinusoidal endothelial cells (LSECs) into pressure and matrix changes. METHODS:We isolated primary LSECs from mice and induced mechanical stretch with a Flexcell device, to recapitulate the pulsatile forces induced by congestion, and performed microarray and RNA-sequencing analyses to identify gene expression patterns associated with stretch. We also performed studies with C57BL/6 mice (controls), mice with deletion of neutrophil elastase (NE-/-) or peptidyl arginine deiminase type IV (Pad4-/-) (enzymes that formation of neutrophil extracellular traps [NETs]), and mice with LSEC-specific deletion of Notch1 (Notch1i?EC). We performed partial ligation of the suprahepatic inferior vena cava (pIVCL) to simulate congestive hepatopathy-induced portal hypertension in mice; some mice were given subcutaneous injections of sivelestat or underwent bile-duct ligation. Portal pressure was measured using a digital blood pressure analyzer and we performed intravital imaging of livers of mice. RESULTS:Expression of the neutrophil chemoattractant CXCL1 was up-regulated in primary LSECs exposed to mechanical stretch, compared with unexposed cells. Intravital imaging of livers in control mice revealed sinusoidal complexes of neutrophils and platelets and formation of NETs after pIVCL. NE-/- and Pad4-/- mice had lower portal pressure and livers had less fibrin compared with control mice after pIVCL and bile-duct ligation; neutrophil recruitment into sinusoidal lumen of liver might increase portal pressure by promoting sinusoid microthrombi. RNA-sequencing of LSECs identified proteins in mechanosensitive signaling pathways that are altered in response to mechanical stretch, including integrins, Notch1, and calcium signaling pathways. Mechanical stretch of LSECs increased expression of CXCL1 via integrin-dependent activation of transcription factors regulated by Notch and its interaction with the mechanosensitive piezo calcium channel. CONCLUSIONS:In studies of LSECs and knockout mice, we identified mechanosensitive angiocrine signals released by LSECs which promote PHTN by recruiting sinusoidal neutrophils and promoting formation of NETs and microthrombi. Strategies to target these pathways might be developed for treatment of PHTN. RNA-sequencing accession number: GSE119547.

SUBMITTER: Hilscher MB

PROVIDER: S-EPMC6581607 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Mechanical Stretch Increases Expression of CXCL1 in Liver Sinusoidal Endothelial Cells to Recruit Neutrophils, Generate Sinusoidal Microthombi, and Promote Portal Hypertension.

Hilscher Moira B MB Sehrawat Tejasav T Arab Juan P JP Zeng Zhutian Z Gao Jinhang J Liu Mengfei M Kostallari Enis E Gao Yandong Y Simonetto Douglas A DA Yaqoob Usman U Cao Sheng S Revzin Alexander A Beyder Arthur A Wang Rong A RA Kamath Patrick S PS Kubes Paul P Shah Vijay H VH

Gastroenterology 20190311 1

<h4>Background & aims</h4>Mechanical forces contribute to portal hypertension (PHTN) and fibrogenesis. We investigated the mechanisms by which forces are transduced by liver sinusoidal endothelial cells (LSECs) into pressure and matrix changes.<h4>Methods</h4>We isolated primary LSECs from mice and induced mechanical stretch with a Flexcell device, to recapitulate the pulsatile forces induced by congestion, and performed microarray and RNA-sequencing analyses to identify gene expression patterns ...[more]

PMID: 30872106

Similar Datasets

Project description:Abstract: Background and aims: Portal hypertension (PH) is the most frequent and severe clinical syndrome associated to chronic liver disease (CLD), defined by a pathological increase in the hepatic venous pressure gradient (HVPG). Considering the known mechanobiological effects of hydrostatic pressure and shear stress on endothelial cells, we hypothesized that PH could not only be a consequence of, but significantly influence the phenotype of liver sinusoidal endothelial cells (LSECs) during disease progression. The aim of this study was to investigate the effects of pathological hydrodynamic pressure on LSECs and to identify endothelial-derived biomarkers of PH. Methods: Primary LSECs were cultured under normal or increased hydrodynamic pressure within a pathophysiological range (1 vs 12 mmHg) using a microfluidic liver-on-a-chip device. RNAseq was used to identify pressure-sensitive genes, which were validated in liver biopsies from two independent cohorts of CLD patients with PH (n=73) vs subjects without PH (n=23). Biomarker discovery was performed in plasma from a third independent cohort of 64 patients (46 with PH vs 18 w/o). Results: Transcriptomic analysis revealed a marked deleterious effect of pathological pressure in LSECs and identified chromobox 7 (CBX7) as a key transcription factor diminished by pressure. Hepatic CBX7 downregulation was validated in patients with PH and significantly correlated with HVPG. MicroRNA 181a-5p was identified as pressure-induced upstream regulator of CBX7. Analysis of two downstream targets of CBX7, ECAD and SPINK1, were found increased in the bloodstream of patients with PH and were highly predictive of PH and clinically significant PH, with a sensitivity of 91.3% and 91.4% respectively. Conclusions: We describe the detrimental effects of increased hydrodynamic pressure on the sinusoidal endothelium, identify CBX7 as a pressure-sensitive transcription factor, and propose that the combination of two of its reported products could be used as plasma biomarkers of PH.

Dataset Information

Mechanical Stretch Increases Expression of CXCL1 in Liver Sinusoidal Endothelial Cells to Recruit Neutrophils, Generate Sinusoidal Microthombi, and Promote Portal Hypertension.

Publications

Mechanical Stretch Increases Expression of CXCL1 in Liver Sinusoidal Endothelial Cells to Recruit Neutrophils, Generate Sinusoidal Microthombi, and Promote Portal Hypertension.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets