| 1. |
- Caolo, Vincenza, et al.
(författare)
-
Shear Stress and VE-Cadherin : The Molecular Mechanism of Vascular Fusion
- 2018
-
Ingår i: Arteriosclerosis, Thrombosis and Vascular Biology. - : LIPPINCOTT WILLIAMS & WILKINS. - 1079-5642 .- 1524-4636. ; 38:9, s. 2174-2183
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: Vascular fusion represents an important mechanism of vessel enlargement during development; however, its significance in postnatal vessel enlargement is still unknown. During fusion, 2 adjoining vessels merge to share 1 larger lumen. The aim of this research was to identify the molecular mechanism responsible for vascular fusion.Approach and Results: We previously showed that both low shear stress and DAPT (N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester) treatment in the embryo result in a hyperfused vascular plexus and that increasing shear stress levels could prevent DAPT-induced fusion. We, therefore, investigated vascular endothelial-cadherin (VEC) phosphorylation because this is a common downstream target of low shear stress and DAPT treatment. VEC phosphorylation increases after DAPT treatment and decreased shear stress. The increased phosphorylation occurred independent of the cleavage of the Notch intracellular domain. Increasing shear stress rescues hyperfusion by DAPT treatment by causing the association of the phosphatase vascular endothelial-protein tyrosine phosphatase with VEC, counteracting VEC phosphorylation. Finally, Src (proto-oncogene tyrosine-protein kinase Src) inhibition prevents VEC phosphorylation in endothelial cells and can rescue hyperfusion induced by low shear stress and DAPT treatment. Moesin, a VEC target that was previously reported to mediate endothelial cell rearrangement during lumenization, relocalizes to cell membranes in vascular beds undergoing hyperfusion.Conclusions: This study provides the first evidence that VEC phosphorylation, induced by DAPT treatment and low shear stress, is involved in the process of fusion during vascular remodeling.
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Kreuger, Johan, et al.
(författare)
-
Early lymph vessel development from embryonic stem cells
- 2006
-
Ingår i: Arteriosclerosis, Thrombosis and Vascular Biology. - 1079-5642 .- 1524-4636. ; 26:5, s. 1073-1078
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: The purpose of this study was to establish a model system for lymph vessel development based on directed differentiation of murine embryonic stem cells. METHODS AND RESULTS: Stem cells were aggregated to form embryoid bodies, and subsequently cultured in 3-dimensional collagen matrix for up to 18 days. Treatment with vascular endothelial growth factor (VEGF)-C and VEGF-A individually enhanced formation of lymphatic vessel structures, although combined treatment with VEGF-C and VEGF-A was most potent and gave rise to a network of LYVE-1, podoplanin, Prox1, and VEGF receptor-3 positive lymphatic vessel structures running parallel to and apparently emanating from, capillaries. In contrast, fibroblast growth factor-2, hepatocyte growth factor, or hypoxia had little or no effect on the development of the early lymphatics. Further, cells of hematopoietic origin were shown to express lymphatic markers. In summary, different subpopulations of lymphatic endothelial cells were identified on the basis of differential expression of several lymphatic and blood vessel markers, indicating vascular heterogeneity. CONCLUSIONS: We conclude that the present model closely mimics the early steps of lymph vessel development in mouse embryos.
|
|
| 6. |
- Le Jan, Sébastien, et al.
(författare)
-
Functional Overlap Between Chondroitin and Heparan Sulfate Proteoglycans During VEGF-Induced Sprouting Angiogenesis
- 2012
-
Ingår i: Arteriosclerosis, Thrombosis and Vascular Biology. - 1079-5642 .- 1524-4636. ; 32:5, s. 1255-1263
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Heparan sulfate proteoglycans regulate key steps of blood vessel formation. The present study was undertaken to investigate if there is a functional overlap between heparan sulfate proteoglycans and chondroitin sulfate proteoglycans during sprouting angiogenesis.METHODS AND RESULTS: Using cultures of genetically engineered mouse embryonic stem cells, we show that angiogenic sprouting occurs also in the absence of heparan sulfate biosynthesis. Cells unable to produce heparan sulfate instead increase their production of chondroitin sulfate that binds key angiogenic growth factors such as vascular endothelial growth factor A, TGFβ, and platelet-derived growth factor B. Lack of heparan sulfate proteoglycan production however leads to increased pericyte numbers and reduced adhesion of pericytes to nascent sprouts, likely due to dysregulation of TGFβ and platelet-derived growth factor B signal transduction.CONCLUSIONS: The present study provides direct evidence for a previously undefined functional overlap between chondroitin sulfate proteoglycans and heparan sulfate proteoglycans during sprouting angiogenesis. Our findings provide information relevant for potential future drug design efforts that involve targeting of proteoglycans in the vasculature.
|
|
| 7. |
|
|
| 8. |
- Magnusson, Peetra U., et al.
(författare)
-
Platelet-derived growth factor receptor-beta constitutive activity promotes angiogenesis in vivo and in vitro
- 2007
-
Ingår i: Arteriosclerosis, Thrombosis and Vascular Biology. - 1079-5642 .- 1524-4636. ; 27:10, s. 2142-2149
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE - Knockout studies have demonstrated crucial roles for the platelet-derived growth factor-B and its cognate receptor, platelet-derived growth factor receptor-β (PDGFR-β), in blood vessel maturation, that is, the coverage of newly formed vessels with mural cells/pericytes. This study describes the consequences of a constitutively activating mutation of the PDGFR-β (Pdgfrb) introduced into embryonic stem cells with respect to vasculogenesis/angiogenesis in vitro and in vivo. METHODS AND RESULTS - Embryonic stem cells were induced to either form teratomas in vivo or embryoid bodies, an in vitro model for mouse embryogenesis. Western blotting studies on embryoid bodies showed that expression of a single allele of the mutant Pdgfrb led to increased levels of PDGFR-β tyrosine phosphorylation and augmented downstream signal transduction. This was accompanied by enhanced vascular development, followed by exaggerated angiogenic sprouting with abundant pericyte coating as shown by immunohistochemistry/immunofluorescence. Pdgfrb embryoid bodies were characterized by increased expression of vascular endothelial growth factor (VEGF)-A and VEGF receptor-2; neutralizing antibodies against VEGF-A/VEGF receptor-2 blocked vasculogenesis and angiogenesis in mutant embryoid bodies. Moreover, Pdgfrb embryonic stem cell-derived teratomas in nude mice were more densely vascularized than wild-type teratomas. CONCLUSION - Increased PDGFR-β kinase activity is associated with elevated expression of VEGF-A and VEGF receptor-2, acting directly on endothelial cells and resulting in increased vessel formation.
|
|
| 9. |
- Matsumoto, Taro, et al.
(författare)
-
Ninein Is Expressed in the Cytoplasm of Angiogenic Tip-Cells and Regulates Tubular Morphogenesis of Endothelial Cells
- 2008
-
Ingår i: Arteriosclerosis, Thrombosis and Vascular Biology. - 1079-5642 .- 1524-4636. ; 28, s. 2123-2130
-
Tidskriftsartikel (refereegranskat)abstract
- Objective— Angiogenesis is an integral part of many physiologicalprocesses but may also aggravate pathological conditions suchas cancer. Development of effective angiogenesis inhibitorsrequires a thorough understanding of the molecular mechanismsregulating vessel formation. The aim of this project was toidentify proteins that regulate tubular morphogenesis of endothelialcells.Methods and Results— Phosphotyrosine-dependent affinity-purificationand mass spectrometry showed tyrosine phosphorylation of nineinduring tubular morphogenesis of endothelial cells. Ninein wasrecently identified as a centrosomal microtubule-anchoring protein.Our results show that ninein is localized in the cytoplasm inendothelial cells, and that it is highly expressed in the vasculaturein normal and pathological human tissues. Using embryoid bodiesas a model of vascular development, we found that ninein isabundantly expressed in the cytoplasm of endothelial cells duringsprouting angiogenesis, in particular in the sprouting tip-cell.In accordance, siRNA-dependent silencing of ninein in endothelialcells inhibited tubular morphogenesis.Conclusions— In this study, we show that ninein is expressedin developing vessels and in endothelial tip cells, and thatninein is critical for formation of the vascular tube. Thesedata strongly implicate ninein as an important new regulatorof angiogenesis.Proteins orchestrating morphological changes accompanying formationof the vascular tube constitute new targets for antiangiogenictherapy. In this study, we identify the microtubule-anchoringprotein ninein as an important new regulator of tubular morphogenesisof endothelial cells. This is the first report of a functionalrole of ninein in angiogenesis.
|
|
