Project description:Vascular permeability is frequently associated with inflammation and it is triggered by chemokines and by a cohort of secreted permeability factors, such as VEGF. In contrast, here we showed that the physiological vascular permeability that precedes implantation is directly controlled by progesterone receptor (PR) and it is independent of VEGF. Both global and endothelial-specific deletion of PR block physiological vascular permeability in the uterus while misexpression of PR in the endothelium of other organs results in ectopic vascular leakage. Integration of genome-wide transcriptional profile of endothelium and ChIP-sequencing revealed that PR induces a NR4A1 (Nur77/TR3) specific transcriptional program that broadly regulates vascular permeability in response to progesterone. This program triggers concurrent suppression of several junctional proteins and leads to an effective, timely and venule-specific regulation of vascular barrier function. Silencing NR4A1 blocks PR-mediated permeability responses indicating a direct link between PR and NR4A1. These results reveal a previously unknown function for progesterone receptor on endothelial cell biology with consequences to physiological vascular permeability and implications to the clinical use of progestins and anti-progestins on blood vessel integrity. Examination of PR target genes in human umbilical vein endothelial cells (HUVECs) using RNA-seq (PR infected only -PR only and PR infected followed by ligand treatment-PR+P)
Project description:Vascular permeability is frequently associated with inflammation and it is triggered by chemokines and by a cohort of secreted permeability factors, such as VEGF. In contrast, here we showed that the physiological vascular permeability that precedes implantation is directly controlled by progesterone receptor (PR) and it is independent of VEGF. Both global and endothelial-specific deletion of PR block physiological vascular permeability in the uterus while misexpression of PR in the endothelium of other organs results in ectopic vascular leakage. Integration of genome-wide transcriptional profile of endothelium and ChIP-sequencing revealed that PR induces a NR4A1 (Nur77/TR3) specific transcriptional program that broadly regulates vascular permeability in response to progesterone. This program triggers concurrent suppression of several junctional proteins and leads to an effective, timely and venule-specific regulation of vascular barrier function. Silencing NR4A1 blocks PR-mediated permeability responses indicating a direct link between PR and NR4A1. These results reveal a previously unknown function for progesterone receptor on endothelial cell biology with consequences to physiological vascular permeability and implications to the clinical use of progestins and anti-progestins on blood vessel integrity. Examination of PR binding sites in HUVEC cells using ChIP-seq (non-infected-negative control, PR infected followed by ligand treatment-PR+P or vehicle PR)
Project description:Vascular permeability is frequently associated with inflammation and it is triggered by chemokines and by a cohort of secreted permeability factors, such as VEGF. In contrast, here we showed that the physiological vascular permeability that precedes implantation is directly controlled by progesterone receptor (PR) and it is independent of VEGF. Both global and endothelial-specific deletion of PR block physiological vascular permeability in the uterus while misexpression of PR in the endothelium of other organs results in ectopic vascular leakage. Integration of genome-wide transcriptional profile of endothelium and ChIP-sequencing revealed that PR induces a NR4A1 (Nur77/TR3) specific transcriptional program that broadly regulates vascular permeability in response to progesterone. This program triggers concurrent suppression of several junctional proteins and leads to an effective, timely and venule-specific regulation of vascular barrier function. Silencing NR4A1 blocks PR-mediated permeability responses indicating a direct link between PR and NR4A1. These results reveal a previously unknown function for progesterone receptor on endothelial cell biology with consequences to physiological vascular permeability and implications to the clinical use of progestins and anti-progestins on blood vessel integrity.
Project description:Vascular permeability is frequently associated with inflammation and it is triggered by chemokines and by a cohort of secreted permeability factors, such as VEGF. In contrast, here we showed that the physiological vascular permeability that precedes implantation is directly controlled by progesterone receptor (PR) and it is independent of VEGF. Both global and endothelial-specific deletion of PR block physiological vascular permeability in the uterus while misexpression of PR in the endothelium of other organs results in ectopic vascular leakage. Integration of genome-wide transcriptional profile of endothelium and ChIP-sequencing revealed that PR induces a NR4A1 (Nur77/TR3) specific transcriptional program that broadly regulates vascular permeability in response to progesterone. This program triggers concurrent suppression of several junctional proteins and leads to an effective, timely and venule-specific regulation of vascular barrier function. Silencing NR4A1 blocks PR-mediated permeability responses indicating a direct link between PR and NR4A1. These results reveal a previously unknown function for progesterone receptor on endothelial cell biology with consequences to physiological vascular permeability and implications to the clinical use of progestins and anti-progestins on blood vessel integrity.
Project description:Rationale: Slit2 is a possible modulator of vascular endothelial growth factor (VEGF) - induced angiogenesis, but its effects have not been tested in large animal models. Objective: We studied the effect of Slit2 on therapeutic angiogenesis induced by VEGF receptor 2 (VEGFR2) ligands Vammin and VEGF-DΔNΔC in vivo in rabbit skeletal muscles. The Slit2 target genes were also studied by RNA sequencing (RNA-Seq) in endothelial cells. Methods and Results: Adenoviral intramuscular gene transfers were performed into rabbit hindlimbs. Confocal and multiphoton microscopy were used for blood vessel imaging. Signaling experiments and gene expression analyses were performed to study mechanisms of Slit2 action. Slit2 decreased VEGFR2-mediated vascular permeability. It also reduced VEGFR2-mediated increase in blood perfusion and capillary enlargement, whereas sprouting of the capillaries was increased. Slit2 gene transfer alone did not have any effects on vascular functions or morphology. VEGFR2 activation was not affected by Slit2, but eNOS phosphorylation was diminished. The transcriptome profiling showed Slit2 downregulating angiogenesis-related genes such as nuclear receptor subfamily 4 group A member 1 (NR4A1) and Stanniocalcin-1 (STC-1) as well as genes related to endothelial cell migration and vascular permeability. Conclusions: Combining Slit2 with VEGFs adjusts VEGFR2-mediated angiogenic effects into a more physiological direction. This possibly allows the use of higher VEGF vector doses to achieve a more widespread vector and VEGF distribution in the target tissues leading to a better therapeutic outcome while reducing excess vascular permeability. HUVEC mRNA profiles after adenoviral vector gene transfers in duplicate.
Project description:Rationale: Slit2 is a possible modulator of vascular endothelial growth factor (VEGF) - induced angiogenesis, but its effects have not been tested in large animal models. Objective: We studied the effect of Slit2 on therapeutic angiogenesis induced by VEGF receptor 2 (VEGFR2) ligands Vammin and VEGF-DΔNΔC in vivo in rabbit skeletal muscles. The Slit2 target genes were also studied by RNA sequencing (RNA-Seq) in endothelial cells. Methods and Results: Adenoviral intramuscular gene transfers were performed into rabbit hindlimbs. Confocal and multiphoton microscopy were used for blood vessel imaging. Signaling experiments and gene expression analyses were performed to study mechanisms of Slit2 action. Slit2 decreased VEGFR2-mediated vascular permeability. It also reduced VEGFR2-mediated increase in blood perfusion and capillary enlargement, whereas sprouting of the capillaries was increased. Slit2 gene transfer alone did not have any effects on vascular functions or morphology. VEGFR2 activation was not affected by Slit2, but eNOS phosphorylation was diminished. The transcriptome profiling showed Slit2 downregulating angiogenesis-related genes such as nuclear receptor subfamily 4 group A member 1 (NR4A1) and Stanniocalcin-1 (STC-1) as well as genes related to endothelial cell migration and vascular permeability. Conclusions: Combining Slit2 with VEGFs adjusts VEGFR2-mediated angiogenic effects into a more physiological direction. This possibly allows the use of higher VEGF vector doses to achieve a more widespread vector and VEGF distribution in the target tissues leading to a better therapeutic outcome while reducing excess vascular permeability.
Project description:Angiogenesis is an essential process in human physiology and disease pathology. Particularly, in ischemic disease condition, the proper induction of angiogenesis without vascular leakage will be crucial for its effective therapy. Ginsenosides, triterpenoid saponins from a well-known medicinal plant ginseng, have been considered as a strong candidate for modulating angiogenesis. However, the biologic activity of individual gensenoside compounds and their target pathway have not been elucidated systematically. To find the candidates of vascular-related therapeutic agents, we evaluated in vitro angiogenic efficacy of 10 ginsenosides using tube formation assay with human umbilical vein endothelial cells (HUVECs). Among them, F1 and Rh1 showed strong in vitro angiogenic properties including EC tube formation, proliferation, and migration similar to vascular endothelial growth factor (VEGF). However, RNA transcriptome analysis showed that F1 and Rh1 differentially regulate gene expressions in HUVECs compared to VEGF. Not only that, F1 and Rh1 significantly inhibited vascular endothelial growth factor (VEGF)-induced vascular leakage both in vitro and in vivo. From RNA transcriptome analysis, we identified that nuclear receptor subfamily 4 group A member 1 (NR4A1) is regulated by F1 and Rh1 for suppression of VEGF-induced vascular leakage. By suppressing the expression and transcriptional activity of NR4A1, F1 and Rh1 could stabilize the expression and localization of junctional vascular endothelial (VE)-cadherin. These findings demonstrate that F1 and Rh1 could be potential compounds in the development of vascular pharmaceuticals.
Project description:Enhanced vascular permeability in the pre-metastatic niche facilitates tumor cell extravasation and metastasis. Extracellular vesicles and particles (EVPs) are pivotal mediators of cancer progression, including induction of vascular permeability. We identify a novel mechanism whereby melanoma and osteosarcoma EVPs (B16F10 and K7M2) enhance endothelial cell permeability, tumor extravasation and lung metastasis.In contrast, EVPs from breast tumors (4T1 and 67NR) elicited only mild vascular permeability, tumor cell extravasation, and metastasis. EVP induced vascular leakiness is observed within 48h following tumor implantation and as early one hour following direct injection of the B16F10 or K7M2 derived EVPs in non-tumor bearing mice. Rather than acting directly on endothelial cells, EVPs activated interstitial macrophages (IMs) anddepletion of IM with a CSF1R antibody significantly reduced vascular leakiness and metastatic potential.Subsequent activation of JAK/STAT signaling in IMs induces IL-6 secretion which in turn induces endothelial permeability.B16F10 and K7M2 EVPs highly expressed ITGα5 compared to breast tumors, and knock down ofintegrin-α5impairs IM signaling, vascular permeability and metastasis. Furthermore, in patients Il-6 expression is elevated in tumor-adjacent IMs compared to distant tissues. Our findings identify a key role for IMs in mediating tumor type-specific EVP-driven vascular permeability and metastasis, offering promising targets for therapeutic intervention.