Vascular biology
Abstract
Previously we reported heightened expression of human endogenous retroviral protein HERV-K deoxyuridine triphosphate nucleotidohydrolase (dUTPase) in circulating monocytes and pulmonary arterial (PA) adventitial macrophages of PA hypertension (PAH) patients. Furthermore, recombinant HERV-K dUTPase increased IL6 in PA endothelial cells (PAECs) and caused pulmonary hypertension in rats. Here we show that monocytes overexpressing HERV-K dUTPase as opposed to GFP, can release HERV-K dUTPase in extracellular vesicles (EVs) that cause pulmonary hypertension in mice in association with endothelial mesenchymal transition (EndMT) related to induction of SNAIL/SLUG, and proinflammatory molecules IL6 as well as VCAM1. In PAECs, HERV-K dUTPase requires TLR4-myeloid differentiation primary response (MYD)-88 to increase IL6 and SNAIL/SLUG, and HERV-K dUTPase interaction with melanoma cell adhesion molecule (MCAM) is necessary to upregulate VCAM1. TLR4 engagement induces p-p38 activation of NF-κB in addition to pJNK-pSMAD3 required for SNAIL, and pSTAT1 for IL6. HERV-K dUTPase interaction with MCAM also induces p-p38 activation of NF-κB in addition to pERK1/2-activating transcription factor (ATF)-2 to increase VCAM1. Thus in PAH, monocytes or macrophages can release HERV-K dUTPase in EVs, and HERV-K dUTPase can engage dual receptors and signaling pathways to subvert PAEC transcriptional machinery to induce EndMT and associated pro-inflammatory molecules.
Authors
Shoichiro Otsuki, Toshie Saito, Shalina Taylor, Dan Li, Jan-Renier Moonen, David P. Marciano, Rebecca L. Harper, Aiqin Cao, Lingli Wang, Maria E. Ariza, Marlene Rabinovitch
Abstract
AAA is a disease with high morbidity and mortality, especially when ruptured. The rational of this study was to evaluate the repurposing of lenvatinib, a multi tyrosine kinase inhibitor, in limiting experimental abdominal aortic aneurysm (AAA) growth targeting vascular smooth muscle cells (VSMC) and angiogenesis. We applied systemic and local lenvatinib treatment to elastase-induced murine aortic aneurysms, and RNA profiling identified myosin heavy chain 11 (Myh11) as the most deregulated transcript. Daily oral treatment significantly reduced aneurysm formation in two independent mouse models. In addition, a large animal aneurysm model in hypercholesterolemic low-density lipoprotein receptor knockout (LDLR-/-) Yucatan minipigs was applied to endovascularly deliver Lenvatinib via drug-eluting balloons (DEB). Here, a single local endovascular delivery blocked AAA progression successfully compared to a DEB-delivered control treatment. Reduced VSMC proliferation and a restored contractile phenotype were observed in animal tissues (murine and porcine), as well as AAA patient-derived cells. Apart from increasing MYH11 levels, lenvatinib reduced downstream ERK signaling. Hence, Lenvatinib is a promising new therapy to limit aortic aneurysm expansion upon local endovascular delivery. The tyrosine kinase inhibitor was able to positively affect pathways of key relevance to human AAA disease, even in a potentially new local delivery using DEBs.
Authors
Albert Busch, Jessica Pauli, Greg Winski, Sonja Bleichert, Ekaterina Chernogubova, Susanne Metschl, Hanna Winter, Matthias Trenner, Armin Wiegering, Christoph Otto, Johannes Fischer, Judith Reiser, Julia Werner, Joy Roy, Christine Brostjan, Christoph Knappich, Hans-Henning Eckstein, Valentina Paloschi, Lars Maegdefessel
Abstract
Gorham-Stout disease (GSD) is a sporadically occurring lymphatic disorder. Patients with GSD develop ectopic lymphatic vessels in bone, gradually lose bone, and can have life-threatening complications such as chylothorax. The etiology of GSD is poorly understood and current treatments for this disease are inadequate for most patients. To explore the pathogenesis of GSD, we performed targeted high-throughput sequencing with samples from a GSD patient and identified an activating somatic mutation in KRAS (p.G12V). To characterize the effect of hyperactive KRAS signaling on lymphatic development, we expressed an active form of KRAS (p.G12D) in murine lymphatics (iLECKras mice). We found that iLECKras mice developed lymphatics in bone, which is a hallmark of GSD. We also found that lymphatic valve development and maintenance was altered in iLECKras mice. Because most iLECKras mice developed chylothorax and died before they had significant bone disease, we analyzed the effect of trametinib (an FDA-approved MEK1/2 inhibitor) on lymphatic valve regression in iLECKras mice. Notably, we found that trametinib suppressed this phenotype in iLECKras mice. Together, our results demonstrate that somatic activating mutations in KRAS can be associated with GSD and reveal that hyperactive KRAS signaling stimulates the formation of lymphatics in bone and impairs the development of lymphatic valves. These findings provide insight into the pathogenesis of GSD and suggest that trametinib could be an effective treatment for GSD.
Authors
Nassim Homayun Sepehr, Anna L. McCarter, Raphaël Helaers, Christine Galant, Laurence M. Boon, Pascal Brouillard, Miikka Vikkula, Michael T. Dellinger
Abstract
The stimulator of interferon genes (STING) protein senses cyclic di-nucleotides released in response to double stranded DNA, and functions as an adaptor molecule for type I interferon (IFN-I) signaling by activating IFN-I stimulated genes (ISG). We found impaired T cell infiltration into the peritoneum in response to TNF-α in global and EC-specific STING-/- mice and discovered that T cell transendothelial migration (TEM) across mouse and human endothelial cells (EC) deficient in STING was strikingly reduced compared to control EC, whereas T cells adhesion was not impaired. STING-/- T cells showed no defect in TEM or adhesion to EC, or immobilized endothelial cell expressed molecules ICAM-1 and VCAM-1 compared to WT T cells. Mechanistically, CXCL10, an ISG and a chemoattractant for T cells, was dramatically reduced in TNF-α-stimulated STING-/- EC and genetic loss or pharmacologic antagonism of IFN-type I interferon receptor (IFNAR) pathway reduced T cell TEM. Our data demonstrate a central role for EC STING during T cell TEM that is dependent on the ISG CXCL10 and on IFN-I-IFNAR signaling.
Authors
Marina Anastasiou, Gail A. Newton, Kuljeet Kaur, Francisco J. Carrillo-Salinas, Sasha A. Smolgovsky, Abraham L. Bayer, Vladimir Ilyukha, Shruti Sharma, Alexander Poltorak, Francis W. Luscinskas, Pilar Alcaide
Abstract
SOCS3 is the main inhibitor of the JAK/STAT3 pathway. This pathway is activated by interleukin 6 (IL-6), a major mediator of the cytokine storm during shock. To determine its role in the vascular response to shock, we challenged mice lacking SOCS3 in the adult endothelium (SOCS3iEKO) with a non-lethal dose of lipopolysaccharide (LPS). SOCS3iEKO mice died 16-24 hours post-injection after severe kidney failure. Loss of SOCS3 led to an LPS-induced type I interferon-like program, and high expression of pro-thrombotic and pro-adhesive genes. Consistently, we observed intraluminal leukocyte adhesion and NETosis, as well as retinal venular leukoembolization. Notably, heterozygous mice displayed an intermediate phenotype, suggesting a gene dose effect. In vitro studies were performed to study the role of SOCS3 protein levels in the regulation of the inflammatory response. In HUVEC, pulse-chase experiments showed that SOCS3 protein has a half-life below 20 minutes. Inhibition of SOCS3 ubiquitination and proteasomal degradation leads to protein accumulation and a stronger inhibition of IL-6 signaling and barrier function loss. Together, our data demonstrates that the regulation of SOCS3 protein levels is critical to inhibit IL-6-mediated endotheliopathy during shock and provides a promising new therapeutic avenue to prevent MODS though stabilization of endothelial SOCS3.
Authors
Nina Martino, Ramon Bossardi Ramos, Shuhan Lu, Kara Leyden, Lindsay Tomaszek, Sudeshna Sadhu, Gabrielle Fredman, Ariel Jaitovich, Peter A. Vincent, Alejandro P. Adam
Abstract
Excessive proliferation of vascular smooth muscle cells (SMCs) remains a significant cause of in-stent restenosis. Integrins, which are heterodimeric transmembrane receptors, play a crucial role in SMC biology by binding to the extracellular matrix protein with the actin cytoskeleton within the SMC. Integrin α9 plays an important role in cell motility and autoimmune diseases; however, its role in SMC biology and remodeling remains unclear. Herein, we demonstrate that stimulated human coronary SMCs upregulate α9 expression. Targeting α9 in stimulated human coronary SMCs, using anti–integrin α9 antibody, suppresses synthetic phenotype and inhibits SMC proliferation and migration. To provide definitive evidence, we generated an SMC-specific α9-deficient mouse strain. Genetic ablation of α9 in SMCs suppressed synthetic phenotype and reduced proliferation and migration in vitro. Mechanistically, suppressed synthetic phenotype and reduced proliferation were associated with decreased focal adhesion kinase/steroid receptor coactivator signaling and downstream targets, including phosphorylated ERK, p38 MAPK, glycogen synthase kinase 3β, and nuclear β-catenin, with reduced transcriptional activation of β-catenin target genes. Following vascular injury, SMC-specific α9-deficient mice or wild-type mice treated with murine anti–integrin α9 antibody exhibited reduced injury-induced neointimal hyperplasia at day 28 by limiting SMC migration and proliferation. Our findings suggest that integrin α9 regulates SMC biology, suggesting its potential therapeutic application in vascular remodeling.
Authors
Manish Jain, Rishabh Dev, Prakash Doddapattar, Shigeyuki Kon, Nirav Dhanesha, Anil K. Chauhan
Abstract
Epigenetic modifications of the genome, including DNA methylation, histone methylation/acetylation and noncoding RNAs, have been reported to play a fundamental role in regulating immune response during the progression of atherosclerosis. SETDB2 is a member of the KMT1 family of lysine methyltransferases and members of this family typically methylate histone H3 Lys9 (H3K9), an epigenetic mark associated with gene silencing and previous studies have shown SETDB2 is involved in innate and adaptive immunity, the pro-inflammatory response and hepatic lipid metabolism. Here we report that the expression of SETDB2 is markedly upregulated in human and murine atherosclerotic lesions. The upregulation of SETDB2 is observed in pro-inflammatory M1, but not anti-inflammatory M2 macrophages (MΦ). Notably, we found that genetic deletion of SETDB2 in hematopoietic cells promotes vascular inflammation and enhances the progression of atherosclerosis in bone marrow transfer studies in LDLR knockout mice. Single cell RNA-Seq analysis in isolated CD45+ cells from atherosclerotic plaques from mice with SETDB2 deficient bone marrow revealed a significant increase in inflammatory macrophage population and enhanced expression of genes involved in inflammation, myeloid cell recruitment and lipid metabolism. Additionally, we found that loss of SETDB2 in hematopoietic cells is associated with macrophage accumulation in atherosclerotic lesions, macrophage proliferation and attenuated efferocytosis. Overall, these studies identify SETDB2 as an important inflammatory cell regulator that controls macrophage activation in atherosclerotic plaques.
Authors
Xinbo Zhang, Jonathan Sun, Alberto Canfrán-Duque, Binod Aryal, George Tellides, Ying Ju Chang, Yajaira Suárez, Timothy F. Osborne, Carlos Fernández-Hernando
Abstract
Transitions between cell fates commonly occur in development and disease. However, reversing an unwanted cell transition in order to treat disease remains an unexplored area. Here, we report a successful process of guiding ill-fated transitions toward normalization in vascular calcification. Vascular calcification is a severe complication that increases all-cause mortality of cardiovascular disease but lacks medical therapy. The vascular endothelium is a contributor of osteoprogenitor cells to vascular calcification through endothelial-mesenchymal transitions, in which endothelial cells (ECs) gain plasticity and ability to differentiate into osteoblast-like cells. We created a high throughput screening and identified SB216763, an inhibitor of glycogen synthase kinase 3 (GSK3), as an inducer of osteoblastic-endothelial transition. We demonstrated that SB216763 limits osteogenic differentiation in ECs at an early stage of vascular calcification. Lineage tracing showed that SB216763 redirected osteoblast-like cells to the endothelial lineage and reduced late-stage calcification. We also find that deletion of GSK3beta in osteoblasts recapitulated osteoblastic-endothelial transition and reduced vascular calcification. Overall, inhibition of GSK3beta promoted the transition of cells with osteoblastic characteristic to endothelial differentiation thereby ameliorating vascular calcification.
Authors
Jiayi Yao, Xiuju Wu, Xiaojing Qiao, Daoqin Zhang, Li Zhang, Jocelyn A. Ma, Xinjiang Cai, Kristina I. Boström, Yucheng Yao
Abstract
The molecular mechanisms by which endothelial cells (ECs) regulate pulmonary vascularization and contribute to alveolar epithelial cell development during lung morphogenesis remain unknown. We tested the hypothesis that delta-like 4 (DLL4), an EC Notch ligand, is critical for alveolarization by combining lung mapping and functional studies in human tissue and DLL4-haploinsufficient mice (Dll4+/lacz). DLL4 expressed in a PECAM-restricted manner in capillaries, arteries, and the alveolar septum from the canalicular to alveolar stage in mice and humans. Dll4 haploinsufficiency resulted in exuberant, nondirectional vascular patterning at E17.5 and P6, followed by smaller capillaries and fewer intermediate blood vessels at P14. Vascular defects coincided with polarization of lung EC expression toward JAG1-NICD-HES1 signature and decreased tip cell-like (Car4) markers. Dll4+/lacZ mice had impaired terminal bronchiole development at the canalicular stage and impaired alveolarization upon lung maturity. We discovered that alveolar type I cell (Aqp5) markers progressively decreased in Dll4+/lacZ mice after birth. Moreover, in human lung EC, DLL4 deficiency programmed a hypersprouting angiogenic phenotype cell autonomously. In conclusion, DLL4 is expressed from the canalicular to alveolar stage in mice and humans, and Dll4 haploinsufficiency programs dysmorphic microvascularization, impairing alveolarization. Our study reveals an obligate role for DLL4-regulated angiogenesis in distal lung morphogenesis.
Authors
Sheng Xia, Heather L. Menden, Nick Townley, Sherry M. Mabry, Jeffrey Johnston, Michael F. Nyp, Daniel P. Heruth, Thomas Korfhagen, Venkatesh Sampath
Abstract
After 9/11, threat of nuclear attack on American urban centers prompted government agencies to develop medical radiation countermeasures to mitigate hematopoietic-acute radiation syndrome (H-ARS) and higher-dose gastrointestinal-ARS (GI-ARS) lethality. While re-purposing leukemia drugs that enhance bone marrow repopulation successfully treats H-ARS in pre-clinical models, no mitigator potentially deliverable under mass casualty conditions preserves GI tract. Here we generate anti-ceramide 6B5 single-chain variable fragment (scFv) and show subcutaneous 6B5 scFv delivery at 24h after a 90% lethal GI-ARS dose of 15Gy mitigates mouse lethality, despite administration after DNA repair is complete. We define an alternate target to DNA repair, an evolving pattern of ceramide-mediated endothelial apoptosis post-radiation, which when disrupted by 6B5 scFv, initiates a durable program of tissue repair, permitting crypt, organ and mouse survival. We posit successful pre-clinical development will render anti-ceramide 6B5 scFv a candidate for inclusion in the Strategic National Stockpile for distribution after a radiation catastrophe.
Authors
Jimmy A. Rotolo, Chii Shyang Fong, Sahra Bodo, Prashanth K. B. Nagesh, John D. Fuller, Thivashnee Sharma, Alessandra Piersigilli, Zhigang Zhang, Zvi Fuks, Vijay K. Singh, Richard Kolesnick
No posts were found with this tag.
