LIM Domain Only 2 Regulates Endothelial Proliferation, Angiogenesis, and Tissue Regeneration.

PubMed

Meng, Shu; Matrone, Gianfranco; Lv, Jie; Chen, Kaifu; Wong, Wing Tak; Cooke, John P

2016-10-06

LIM domain only 2 (LMO2, human gene) is a key transcription factor that regulates hematopoiesis and vascular development. However, its role in adult endothelial function has been incompletely characterized. In vitro loss- and gain-of-function studies on LMO2 were performed in human umbilical vein endothelial cells with lentiviral overexpression or short hairpin RNA knockdown (KD) of LMO2, respectively. LMO2 KD significantly impaired endothelial proliferation. LMO2 controls endothelial G1/S transition through transcriptional regulation of cyclin-dependent kinase 2 and 4 as determined by reverse transcription polymerase chain reaction (PCR), western blot, and chromatin immunoprecipitation, and also influences the expression of Cyclin D1 and Cyclin A1. LMO2 KD also impaired angiogenesis by reducing transforming growth factor-β (TGF-β) expression, whereas supplementation of exogenous TGF-β restored defective network formation in LMO2 KD human umbilical vein endothelial cells. In a zebrafish model of caudal fin regeneration, RT-PCR revealed that the lmo2 (zebrafish gene) gene was upregulated at day 5 postresection. The KD of lmo2 by vivo-morpholino injections in adult Tg(fli1:egfp) y1 zebrafish reduced 5-bromo-2'-deoxyuridine incorporation in endothelial cells, impaired neoangiogenesis in the resected caudal fin, and substantially delayed fin regeneration. The transcriptional factor LMO2 regulates endothelial proliferation and angiogenesis in vitro. Furthermore, LMO2 is required for angiogenesis and tissue healing in vivo. Thus, LMO2 is a critical determinant of vascular and tissue regeneration. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Macrophages commit postnatal endothelium-derived progenitors to angiogenesis and restrict endothelial to mesenchymal transition during muscle regeneration.

PubMed

Zordan, P; Rigamonti, E; Freudenberg, K; Conti, V; Azzoni, E; Rovere-Querini, P; Brunelli, S

2014-01-30

The damage of the skeletal muscle prompts a complex and coordinated response that involves the interactions of many different cell populations and promotes inflammation, vascular remodeling and finally muscle regeneration. Muscle disorders exist in which the irreversible loss of tissue integrity and function is linked to defective neo-angiogenesis with persistence of tissue necrosis and inflammation. Here we show that macrophages (MPs) are necessary for efficient vascular remodeling in the injured muscle. In particular, MPs sustain the differentiation of endothelial-derived progenitors to contribute to neo-capillary formation, by secreting pro-angiogenic growth factors. When phagocyte infiltration is compromised endothelial-derived progenitors undergo a significant endothelial to mesenchymal transition (EndoMT), possibly triggered by the activation of transforming growth factor-β/bone morphogenetic protein signaling, collagen accumulates and the muscle is replaced by fibrotic tissue. Our findings provide new insights in EndoMT in the adult skeletal muscle, and suggest that endothelial cells in the skeletal muscle may represent a new target for therapeutic intervention in fibrotic diseases.

Corneal endothelium: developmental strategies for regeneration

PubMed Central

Zavala, J; López Jaime, G R; Rodríguez Barrientos, C A; Valdez-Garcia, J

2013-01-01

The main treatment available for restoration of the corneal endothelium is keratoplasty. This procedure is faced with several difficulties, including the shortage of donor tissue, post-surgical complications associated with the use of drugs to prevent immune rejection, and a significant increase in the occurrence of glaucoma. Recently, surgical procedures such as Descemet's stripping endothelial keratoplasty have focused on the transplant of corneal endothelium, yielding better visual results but still facing the need for donor tissue. The emergent strategies in the field of cell biology and tissue cultivation of corneal endothelial cells aim at the production of transplantable endothelial cell sheets. Cell therapy focuses on the culture of corneal endothelial cells retrieved from the donor, in the donor's cornea, followed by transplantation into the recipient. Recently, research has focused on overcoming the challenge of harvesting human corneal endothelial cells and the generation of new biomembranes to be used as cell scaffolds in surgical procedures. The use of corneal endothelial precursors from the peripheral cornea has also demonstrated to be effective and represents a valuable tool for reducing the risk of rejection in allogeneic transplants. Several animal model reports also support the use of adult stem cells as therapy for corneal diseases. Current results represent important progresses in the development of new strategies based on alternative sources of tissue for the treatment of corneal endotheliopathies. Different databases were used to search literature: PubMed, Google Books, MD Consult, Google Scholar, Gene Cards, and NCBI Books. The main search terms used were: ‘cornea AND embryology AND transcription factors', ‘human endothelial keratoplasty AND risk factors', ‘(cornea OR corneal) AND (endothelium OR endothelial) AND cell culture', ‘mesenchymal stem cells AND cell therapy', ‘mesenchymal stem cells AND cornea', and ‘stem cells AND (cornea OR corneal) AND (endothelial OR endothelium)'. PMID:23470788

Pleiotropy of tissue-specific growth factors: from neurons to vessels via the bone marrow

PubMed Central

Duda, Dan G.; Jain, Rakesh K.

2005-01-01

Recent evidence has demonstrated that endothelial-specific growth factors affect the development of apparently unrelated organs and cells. Expanding this evidence further, new findings in this issue of the JCI show that neurotrophic factors can affect neovascularization. Neurotrophic factors achieve proangiogenic effects not only by directly affecting endothelial cells, but also by recruiting hematopoietic precursors. Further understanding of the biology of angiogenic factors, as well as of the function of hematopoietic cells in tissue neovascularization, will lead to improved therapeutic strategies for the treatment of diseases ranging from ischemia to cancer. PMID:15765145

Semiquantitative immunohistochemical marker staining and localization in canine thyroid carcinoma and normal thyroid gland.

PubMed

Pessina, P; Castillo, V; Sartore, I; Borrego, J; Meikle, A

2016-09-01

Immunoreactive proteins in follicular cells, fibroblasts and endothelial cells were assessed in canine thyroid carcinomas and healthy thyroid glands. No differences were detected in thyrotropin receptor and thyroglobulin staining between cancer and normal tissues, but expression was higher in follicular cells than in fibroblasts. Fibroblast growth factor-2 staining was more intense in healthy follicular cells than in those of carcinomas. Follicular cells in carcinomas presented two- to three-fold greater staining intensity of thyroid transcription factor-1 and proliferating cell nuclear antigen, respectively, than healthy cells, and a similar trend was found for the latter antigen in fibroblasts. Vascular endothelial growth factor staining was more intense in the endothelial cells of tumours than in those of normal tissues. In conclusion, greater expression of factors related to proliferation and angiogenesis was demonstrated in several cell types within thyroid carcinomas compared to healthy tissues, which may represent mechanisms of tumour progression in this disease. © 2014 John Wiley & Sons Ltd.

Endoglin (CD105) expression in the development of haemorrhoids.

PubMed

Chung, Y-C; Hou, Y-C; Pan, A C-H

2004-02-01

Conventional pathogenesis of haemorrhoid emphasized the anchoring connective tissue system, whereas the vascular changes were ignored. The aim of this study was to clarify vascular changes of haemorrhoid disease. Forty-six samples of grade III and grade IV haemorrhoid tissue were selected for an in vitro study. We assessed the expressions in endoglin (CD105), an accessory protein in transforming growth factor-beta receptor complex, in CD34 and in vascular endothelial growth factor by using an immunohistochemical method. Microvascular density was calculated to correlate the expression of endoglin. Microvascular density was higher in haemorrhoid tissue than in normal anal and lower rectal tissues. CD34 was demonstrated in whole vessels in the haemorrhoids. However, endoglin, a proliferative marker of neovascularization, was present in only 25 of 46 (54%) haemorrhoidal vessels, and its immunoactivity was prominent in venules larger than 100 micro m. Thrombosis formation and stromal vascular endothelial growth factor was significantly associated with the presence of endoglin immunoactivity. The results of this study suggest that neovascularization is one important phenomenon of haemorrhoid disease, along with conventional venous dilatation and arteriovenous communication. In addition, thrombosis and stromal vascular endothelial growth factor might be important factors in promoting vascular proliferation.

Vascular endothelial growth factor-D is a key molecule that enhances lymphatic metastasis of soft tissue sarcomas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yanagawa, Takashi, E-mail: tyanagaw@med.gunma-u.ac.jp; Shinozaki, Tetsuya; Watanabe, Hideomi

2012-04-15

Studies on lymph node metastasis of soft tissue sarcomas are insufficient because of its rarity. In this study, we examined the expressions of vascular endothelial growth factor (VEGF)-C and VEGF-D in soft tissue sarcomas metastasized to lymph nodes. In addition, the effects of the two molecules on the barrier function of a lymphatic endothelial cell monolayer against sarcoma cells were analyzed. We examined 7 patients who had soft tissue sarcomas with lymph node metastases and who had undergone neither chemotherapy nor radiotherapy before lymphadenectomy. Immunohistochemistry revealed that 2 of 7 sarcomas that metastasized to lymph nodes expressed VEGF-C both inmore » primary and metastatic lesions. On the other hand, VEGF-D expression was detected in 4 of 7 primary and 7 of 7 metastatic lesions, respectively. Interestingly, 3 cases that showed no VEGF-D expression at primary sites expressed VEGF-D in metastatic lesions. Recombinant VEGF-C at 10{sup -8} and VEGF-D at 10{sup -7}and 10{sup -8} g/ml significantly increased the random motility of lymphatic endothelial cells compared with controls. VEGF-D significantly increased the migration of sarcoma cells through lymphatic endothelial monolayers. The fact that VEGF-D induced the migration of fibrosarcomas through the lymphatic endothelial monolayer is the probable reason for the strong relationship between VEGF-D expression and lymph node metastasis in soft tissue sarcomas. The important propensities of this molecule for the increase of lymph node metastases are not only lymphangiogenesis but also down-regulation of the barrier function of lymphatic endothelial monolayers, which facilitates sarcoma cells entering the lymphatic circulation.« less

Improved vascularization of planar membrane diffusion devices following continuous infusion of vascular endothelial growth factor.

PubMed

Trivedi, N; Steil, G M; Colton, C K; Bonner-Weir, S; Weir, G C

2000-01-01

Improving blood vessel formation around an immunobarrier device should improve the survival of the encapsulated tissue. In the present study we investigated the formation of new blood vessels around a planar membrane diffusion device (the Baxter Theracyte System) undergoing a continuous infusion of vascular endothelial growth factor through the membranes and into the surrounding tissue. Each device (20 microl) had both an inner immunoisolation membrane and an outer vascularizing membrane. Human recombinant vascular endothelial growth factor-165 was infused at 100 ng/day (low dose: n = 6) and 500 ng/day (high dose: n = 7) for 10 days into devices implanted s.c. in Sprague-Dawley rats; noninfused devices transplanted for an identical period were used as controls (n = 5). Two days following the termination of VEGF infusion, devices were loaded with 20 microl of Lispro insulin (1 U/kg) and the kinetics of insulin release from the lumen of the device was assessed. Devices were then explanted and the number of blood vessels (capillary and noncapillary) was quantified using morphometry. High-dose vascular endothelial growth factor infusion resulted in two- to threefold more blood vessels around the device than that obtained with the noninfused devices and devices infused with low-dose vascular endothelial growth factor. This increase in the number of blood vessels was accompanied by a modest increase in insulin diffusion from the device in the high-dose vascular endothelial growth factor infusion group. We conclude that vascular endothelial growth factor can be used to improve blood vessel formation adjacent to planar membrane diffusion devices.

Constructing a blood vessel on the porous scaffold modified with vascular endothelial growth factor and basic fibroblast growth factor

NASA Astrophysics Data System (ADS)

Sevostyanova, V. V.; Matveeva, V. G.; Antonova, L. V.; Velikanova, E. A.; Shabaev, A. R.; Senokosova, E. A.; Krivkina, E. O.; Vasyukov, G. Yu.; Glushkova, T. V.; Kudryavtseva, Yu. A.; Barbarash, O. L.; Barbarash, L. S.

2016-11-01

Incorporation of the growth factors into biodegradable polymers is a promising approach for the fabrication of tissue-engineered vascular grafts. Here we blended poly(ɛ-caprolactone) (PCL) with poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) following incorporation of either vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF) and then fabricated electrospun 2 mm diameter vascular grafts. Grafts without the growth factors were used as a control group. Structure of the grafts was assessed utilizing scanning electron microscopy. We further implanted our grafts into rat abdominal aorta for 1 and 3 months with the aim to test endothelialization, cell infiltration, and patency in vivo. Histological and immunofluorescence examination demonstrated enhanced endothelialization and cell infiltration of the grafts with either VEGF or bFGF compared to those without the growth factors. Grafts with VEGF showed higher patency compared to those with bFGF; however, bFGF promoted migration of smooth muscle cells and fibroblasts into the graft. Therefore, we conclude that incorporation of VEGF and bFGF into the inner and medial/outer layer, respectively, can be a promising option for the fabrication of tissue-engineered vascular grafts.

Ulex europaeus I lectin as a marker for vascular endothelium in human tissues.

PubMed

Holthöfer, H; Virtanen, I; Kariniemi, A L; Hormia, M; Linder, E; Miettinen, A

1982-07-01

Ulex europaeus I agglutinin, a lectin specific for some alpha-L-fucose-containing glycocompounds, was used in fluorescence microscopy to stain cryostat sections of human tissues. The endothelium of vessels of all sizes was stained ubiquitously in all tissues studied as judged by double staining with a known endothelial marker, antibodies against human clotting factor VIII. Cultured human umbilical vein endothelial cells, but not fibroblasts, also bound Ulex lectin. The staining was not affected by the blood group type of the tissue donor. In some tissues Ulex lectin presented additional binding to epithelial structures. Also, this was independent on the blood group or the ability of the tissue donor to secrete soluble blood group substances. Lotus tetragonolobus agglutinin, another lectin specific for some alpha-L-fucose-containing moieties failed to react with endothelial cells. Our results suggest that Ulex europaeus I agglutinin is a good histologic marker for endothelium in human tissues.

Vascular endothelial growth factor c/vascular endothelial growth factor receptor 3 signaling regulates chemokine gradients and lymphocyte migration from tissues to lymphatics.

PubMed

Iwami, Daiki; Brinkman, C Colin; Bromberg, Jonathan S

2015-04-01

Circulation of leukocytes via blood, tissue and lymph is integral to adaptive immunity. Afferent lymphatics form CCL21 gradients to guide dendritic cells and T cells to lymphatics and then to draining lymph nodes (dLN). Vascular endothelial growth factor C and vascular endothelial growth factor receptor 3 (VEGFR-3) are the major lymphatic growth factor and receptor. We hypothesized these molecules also regulate chemokine gradients and lymphatic migration. CD4 T cells were injected into the foot pad or ear pinnae, and migration to afferent lymphatics and dLN quantified by flow cytometry or whole mount immunohistochemistry. Vascular endothelial growth factor receptor 3 or its signaling or downstream actions were modified with blocking monoclonal antibodies (mAbs) or other reagents. Anti-VEGFR-3 prevented migration of CD4 T cells into lymphatic lumen and significantly decreased the number that migrated to dLN. Anti-VEGFR-3 abolished CCL21 gradients around lymphatics, although CCL21 production was not inhibited. Heparan sulfate (HS), critical to establish CCL21 gradients, was down-regulated around lymphatics by anti-VEGFR-3 and this was dependent on heparanase-mediated degradation. Moreover, a Phosphoinositide 3-kinase (PI3K)α inhibitor disrupted HS and CCL21 gradients, whereas a PI3K activator prevented the effects of anti-VEGFR-3. During contact hypersensitivity, VEGFR-3, CCL21, and HS expression were all attenuated, and anti-heparanase or PI3K activator reversed these effects. Vascular endothelial growth factor C/VEGFR-3 signaling through PI3Kα regulates the activity of heparanase, which modifies HS and CCL21 gradients around lymphatics. The functional and physical linkages of these molecules regulate lymphatic migration from tissues to dLN. These represent new therapeutic targets to influence immunity and inflammation.

A Model for Breast Cancer-Induced Angiogenesis

DTIC Science & Technology

1997-09-01

Protein kinase C isozyme expression in phorbol ester- sensitive and -resistant EL4 thymoma cells . J. Biol. Chem. 266:5676-568 1. Jalava A, Akerman K...that exogenous angiogenic factors were unable to stimulate endothelial cell proliferation. Furthermore, under non- stimulated conditions, endothelial... cell proliferation was restricted to the adipose tissue and perilobular connective tissue. The endothelium within the fibrous stroma could almost never

Axon guidance molecules in vascular patterning.

PubMed

Adams, Ralf H; Eichmann, Anne

2010-05-01

Endothelial cells (ECs) form extensive, highly branched and hierarchically organized tubular networks in vertebrates to ensure the proper distribution of molecular and cellular cargo in the vertebrate body. The growth of this vascular system during development, tissue repair or in disease conditions involves the sprouting, migration and proliferation of endothelial cells in a process termed angiogenesis. Surprisingly, specialized ECs, so-called tip cells, which lead and guide endothelial sprouts, share many feature with another guidance structure, the axonal growth cone. Tip cells are motile, invasive and extend numerous filopodial protrusions sensing growth factors, extracellular matrix and other attractive or repulsive cues in their tissue environment. Axonal growth cones and endothelial tip cells also respond to signals belonging to the same molecular families, such as Slits and Roundabouts, Netrins and UNC5 receptors, Semaphorins, Plexins and Neuropilins, and Eph receptors and ephrin ligands. Here we summarize fundamental principles of angiogenic growth, the selection and function of tip cells and the underlying regulation by guidance cues, the Notch pathway and vascular endothelial growth factor signaling.

Angiocrine functions of organ-specific endothelial cells

PubMed Central

Rafii, Shahin; Butler, Jason M; Ding, Bi-Sen

2016-01-01

Preface Endothelial cells lining blood vessel capillaries are not just passive conduits for delivering blood. Tissue-specific endothelium establish specialized vascular niches that deploy specific sets of growth factors, known as angiocrine factors, which actively participate in inducing, specifying, patterning, and guiding organ regeneration and maintaining homeostasis and metabolism. Angiocrine factors upregulated in response to injury orchestrates self-renewal and differentiation of tissue-specific repopulating resident stem and progenitor cells into functional organs. Uncovering the precise mechanisms whereby physiological-levels of angiocrine factors are spatially and temporally produced, and distributed by organotypic endothelium to repopulating cells, will lay the foundation for driving organ repair without scarring. PMID:26791722

Regulator of Calcineurin 1 in Periodontal Disease

PubMed Central

Peters, Ulrike; Solominidou, Eleni; Korkmaz, Yüksel; Rüttermann, Stefan; Klocke, Astrid; Flemmig, Thomas Frank; Beikler, Thomas

2016-01-01

Nuclear factor of activated T-cells (NFAT) and NF-kB pathway associated processes are involved in the pathogenesis of various inflammatory disorders, for example, periodontal disease. The activation of these pathways is controlled by the regulator of calcineurin 1 (RCAN1). The aim of this study was to elucidate the role of RCAN1 in periodontal disease. Healthy and inflamed periodontal tissues were analyzed by immunohistochemistry and immunofluorescence using specific rabbit polyclonal anti-RCAN1 antibodies. For expression analysis human umbilical vein endothelial cells (HUVEC) were used. HUVEC were incubated for 2 h with Vascular Endothelial Growth Factor (VEGF) or with wild type and laboratory strains of Porphyromonas gingivalis (P. gingivalis). Expression analysis of rcan1 and cox2 was done by real time PCR using specific primers for rcan1.4 and cox2. The expression of rcan1 was found to be significantly suppressed in endothelial cells of chronically inflamed periodontal tissues compared to healthy controls. Rcan1 and cox2 were significantly induced by VEGF and wild type and laboratory P. gingivalis strains. Interestingly, the magnitude of the rcan1 and cox2 induction was strain dependent. The results of this study indicate that RCAN1 is suppressed in endothelial cells of chronically inflamed periodontal tissues. During an acute infection, however, rcan1 seems to be upregulated in endothelial cells, indicating a modulating role in immune homeostasis of periodontal tissues. PMID:27403036

Instructive role of the vascular niche in promoting tumour growth and tissue repair by angiocrine factors

PubMed Central

Butler, Jason M.; Kobayashi, Hideki; Rafii, Shahin

2010-01-01

The precise mechanisms whereby anti-angiogenesis therapy blocks tumour growth or causes vascular toxicity are unknown. We propose that endothelial cells establish a vascular niche that promotes tumour growth and tissue repair not only by delivering nutrients and O2 but also through an ‘angiocrine’ mechanism by producing stem and progenitor cell-active trophogens. Identification of endothelial-derived instructive angiocrine factors will allow direct tumour targeting, while diminishing the unwanted side effects associated with the use of anti-angiogenic agents. PMID:20094048

Instructive role of the vascular niche in promoting tumour growth and tissue repair by angiocrine factors.

PubMed

Butler, Jason M; Kobayashi, Hideki; Rafii, Shahin

2010-02-01

The precise mechanisms whereby anti-angiogenesis therapy blocks tumour growth or causes vascular toxicity are unknown. We propose that endothelial cells establish a vascular niche that promotes tumour growth and tissue repair not only by delivering nutrients and O2 but also through an 'angiocrine' mechanism by producing stem and progenitor cell-active trophogens. Identification of endothelial-derived instructive angiocrine factors will allow direct tumour targeting, while diminishing the unwanted side effects associated with the use of anti-angiogenic agents.

Tissue factor expression by endothelial cells in sickle cell anemia.

PubMed

Solovey, A; Gui, L; Key, N S; Hebbel, R P

1998-05-01

The role of the vascular endothelium in activation of the coagulation system, a fundamental homeostatic mechanism of mammalian biology, is uncertain because there is little evidence indicating that endothelial cells in vivo express tissue factor (TF), the system's triggering mechanism. As a surrogate for vessel wall endothelium, we examined circulating endothelial cells (CEC) from normals and patients with sickle cell anemia, a disease associated with activation of coagulation. We find that sickle CEC abnormally express TF antigen (expressed as percent CEC that are TF-positive), with 66+/-13% positive in sickle patients in steady-state, 83+/-19% positive in sickle patients presenting with acute vasoocclusive episodes, and only 10+/-13% positive in normal controls. Repeated samplings confirmed this impression that TF expression is greater when sickle patients develop acute vasoocclusive episodes. Sickle CEC are also positive for TF mRNA, with excellent concurrence between antigen and mRNA expression. The TF expressed on the antigen-positive CEC is functional, as demonstrated by a binding assay for Factor VIIa and a chromogenic assay sensitive to generation of Factor Xa. By establishing that endothelial cells in vivo can express TF, these data imply that the vast endothelial surface area does provide an important pathophysiologic trigger for coagulation activation.

EFFECTS OF IRRADIATION ON BRAIN VASCULATURE USING AN IN SITU TUMOR MODEL

PubMed Central

Zawaski, Janice A.; Gaber, M. Waleed; Sabek, Omaima M.; Wilson, Christy M.; Duntsch, Christopher D.; Merchant, Thomas E.

2013-01-01

Purpose Damage to normal tissue is a limiting factor in clinical radiotherapy (RT). We tested the hypothesis that the presence of tumor alters the response of normal tissues to irradiation using a rat in situ brain tumor model. Methods and Materials Intravital microscopy was used with a rat cranial window to assess the in situ effect of rat C6 glioma on peritumoral tissue with and without RT. The RT regimen included 40 Gy at 8 Gy/day starting Day 5 after tumor implant. Endpoints included blood–brain barrier permeability, clearance index, leukocyte-endothelial interactions and staining for vascular endothelial growth factor (VEGF) glial fibrillary acidic protein, and apoptosis. To characterize the system response to RT, animal survival and tumor surface area and volume were measured. Sham experiments were performed on similar animals implanted with basement membrane matrix absent of tumor cells. Results The presence of tumor alone increases permeability but has little effect on leukocyte–endothelial interactions and astrogliosis. Radiation alone increases tissue permeability, leukocyte-endothelial interactions, and astrogliosis. The highest levels of permeability and cell adhesion were seen in the model that combined tumor and irradiation; however, the presence of tumor appeared to reduce the volume of rolling leukocytes. Unirradiated tumor and peritumoral tissue had poor clearance. Irradiated tumor and peritumoral tissue had a similar clearance index to irradiated and unirradiated sham-implanted animals. Radiation reduces the presence of VEGF in peritumoral normal tissues but did not affect the amount of apoptosis in the normal tissue. Apoptosis was identified in the tumor tissue with and without radiation. Conclusions We developed a novel approach to demonstrate that the presence of the tumor in a rat intracranial model alters the response of normal tissues to irradiation. PMID:22197233

Molecular Signatures of Tissue-Specific Microvascular Endothelial Cell Heterogeneity in Organ Maintenance and Regeneration

PubMed Central

Nolan, Daniel J.; Ginsberg, Michael; Israely, Edo; Palikuqi, Brisa; Poulos, Michael G.; James, Daylon; Ding, Bi-Sen; Schachterle, William; Liu, Ying; Rosenwaks, Zev; Butler, Jason M.; Xiang, Jenny; Rafii, Arash; Shido, Koji; Rabbany, Sina Y.; Elemento, Olivier; Rafii, Shahin

2013-01-01

SUMMARY Microvascular endothelial cells (ECs) within different tissues are endowed with distinct but as yet unrecognized structural, phenotypic, and functional attributes. We devised EC purification, cultivation, profiling, and transplantation models that establish tissue-specific molecular libraries of ECs devoid of lymphatic ECs or parenchymal cells. These libraries identify attributes that confer ECs with their organotypic features. We show that clusters of transcription factors, angiocrine growth factors, adhesion molecules, and chemokines are expressed in unique combinations by ECs of each organ. Furthermore, ECs respond distinctly in tissue regeneration models, hepatectomy, and myeloablation. To test the data set, we developed a transplantation model that employs generic ECs differentiated from embryonic stem cells. Transplanted generic ECs engraft into regenerating tissues and acquire features of organotypic ECs. Collectively, we demonstrate the utility of informational databases of ECs toward uncovering the extravascular and intrinsic signals that define EC heterogeneity. These factors could be exploited therapeutically to engineer tissue-specific ECs for regeneration. PMID:23871589

Platelet-rich fibrin matrix improves wound angiogenesis via inducing endothelial cell proliferation.

PubMed

Roy, Sashwati; Driggs, Jason; Elgharably, Haytham; Biswas, Sabyasachi; Findley, Muna; Khanna, Savita; Gnyawali, Urmila; Bergdall, Valerie K; Sen, Chandan K

2011-11-01

The economic, social, and public health burden of chronic ulcers and other compromised wounds is enormous and rapidly increasing with the aging population. The growth factors derived from platelets play an important role in tissue remodeling including neovascularization. Platelet-rich plasma (PRP) has been utilized and studied for the last four decades. Platelet gel and fibrin sealant, derived from PRP mixed with thrombin and calcium chloride, have been exogenously applied to tissues to promote wound healing, bone growth, hemostasis, and tissue sealing. In this study, we first characterized recovery and viability of as well as growth factor release from platelets in a novel preparation of platelet gel and fibrin matrix, namely platelet-rich fibrin matrix (PRFM). Next, the effect of PRFM application in a delayed model of ischemic wound angiogenesis was investigated. The study, for the first time, shows the kinetics of the viability of platelet-embedded fibrin matrix. A slow and steady release of growth factors from PRFM was observed. The vascular endothelial growth factor released from PRFM was primarily responsible for endothelial mitogenic response via extracellular signal-regulated protein kinase activation pathway. Finally, this preparation of PRFM effectively induced endothelial cell proliferation and improved wound angiogenesis in chronic wounds, providing evidence of probable mechanisms of action of PRFM in healing of chronic ulcers. 2011 by the Wound Healing Society.

Immunohistochemical expression of vascular endothelial growth factor in canine oral squamous cell carcinomas.

PubMed

Martano, Manuela; Restucci, Brunella; Ceccarelli, Dora Maria; Lo Muzio, Lorenzo; Maiolino, Paola

2016-01-01

Angiogenesis is crucial for the growth and metastasis of malignant tumours, and various proangiogenic factors promote this process. One of these factors is vascular endothelial growth factor (VEGF), which appears to play a key role in tumour angiogenesis. The aim of the present study was to assess whether VEGF expression is associated with angiogenesis, disease progression and neoplastic proliferation in canine oral squamous cell carcinoma (OSCC) tissue. VEGF immunoreactivity was quantified by immunohistochemistry in 30 specimens, including normal oral mucosa and OSCC tissues graded as well, moderately or poorly differentiated. VEGF expression was correlated with tumour cell proliferation, as assessed using the proliferating cell nuclear antigen (PCNA) marker and microvessel density (data already published). The present results revealed that VEGF and PCNA expression increased significantly between normal oral tissue and neoplastic tissue, and between well and moderately/poorly differentiated tumours. In addition, VEGF expression was strongly correlated with PCNA expression and microvessel density. It was concluded that VEGF may promote angiogenesis through a paracrine pathway, stimulating endothelial cell proliferation and, similarly, may induce tumour cell proliferation through an autocrine pathway. The present results suggest that the evaluation of VEGF may be a useful additional criterion for estimating malignancy and growth potential in canine OSCCs.

Priming Dental Pulp Stem Cells With Fibroblast Growth Factor-2 Increases Angiogenesis of Implanted Tissue-Engineered Constructs Through Hepatocyte Growth Factor and Vascular Endothelial Growth Factor Secretion

PubMed Central

Gorin, Caroline; Rochefort, Gael Y.; Bascetin, Rumeyza; Ying, Hanru; Lesieur, Julie; Sadoine, Jérémy; Beckouche, Nathan; Berndt, Sarah; Novais, Anita; Lesage, Matthieu; Hosten, Benoit; Vercellino, Laetitia; Merlet, Pascal; Le-Denmat, Dominique; Marchiol, Carmen; Letourneur, Didier; Nicoletti, Antonino; Vital, Sibylle Opsahl; Poliard, Anne; Salmon, Benjamin; Germain, Stéphane

2016-01-01

Tissue engineering strategies based on implanting cellularized biomaterials are promising therapeutic approaches for the reconstruction of large tissue defects. A major hurdle for the reliable establishment of such therapeutic approaches is the lack of rapid blood perfusion of the tissue construct to provide oxygen and nutrients. Numerous sources of mesenchymal stem cells (MSCs) displaying angiogenic potential have been characterized in the past years, including the adult dental pulp. Establishment of efficient strategies for improving angiogenesis in tissue constructs is nevertheless still an important challenge. Hypoxia was proposed as a priming treatment owing to its capacity to enhance the angiogenic potential of stem cells through vascular endothelial growth factor (VEGF) release. The present study aimed to characterize additional key factors regulating the angiogenic capacity of such MSCs, namely, dental pulp stem cells derived from deciduous teeth (SHED). We identified fibroblast growth factor-2 (FGF-2) as a potent inducer of the release of VEGF and hepatocyte growth factor (HGF) by SHED. We found that FGF-2 limited hypoxia-induced downregulation of HGF release. Using three-dimensional culture models of angiogenesis, we demonstrated that VEGF and HGF were both responsible for the high angiogenic potential of SHED through direct targeting of endothelial cells. In addition, FGF-2 treatment increased the fraction of Stro-1+/CD146+ progenitor cells. We then applied in vitro FGF-2 priming to SHED before encapsulation in hydrogels and in vivo subcutaneous implantation. Our results showed that FGF-2 priming is more efficient than hypoxia at increasing SHED-induced vascularization compared with nonprimed controls. Altogether, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both HGF and VEGF. Significance The results from the present study show that fibroblast growth factor-2 (FGF-2) priming is more efficient than hypoxia at increasing dental pulp stem cells derived from deciduous teeth (SHED)-induced vascularization compared with nonprimed controls. Together, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both hepatocyte growth factor and vascular endothelial growth factor. PMID:26798059

CIRCULATING MICROPARTICLES IN PATIENTS WITH ANTIPHOSPHOLIPID ANTIBODIES: CHARACTERIZATION AND ASSOCIATIONS

PubMed Central

Chaturvedi, Shruti; Cockrell, Erin; Espinola, Ricardo; Hsi, Linda; Fulton, Stacey; Khan, Mohammad; Li, Liang; Fonseca, Fabio; Kundu, Suman; McCrae, Keith R.

2014-01-01

The antiphospholipid syndrome is characterized by venous or arterial thrombosis and/or recurrent fetal loss in the presence of circulating antiphospholipid antibodies. These antibodies cause activation of endothelial and other cell types leading to the release of microparticles with procoagulant and pro-inflammatory properties. The aims of this study were to characterize the levels of endothelial cell, monocyte, platelet derived, and tissue factor-bearing microparticles in patients with antiphospholipid antibodies, to determine the association of circulating microparticles with anticardiolipin and anti-β2-glycoprotein antibodies, and to define the cellular origin of microparticles that express tissue factor. Microparticle content within citrated blood from 47 patients with antiphospholipid antibodies and 144 healthy controls was analyzed within 2 hours of venipuncture. Levels of Annexin-V, CD105 and CD144 (endothelial derived), CD41 (platelet derived) and tissue factor positive microparticles were significantly higher in patients than controls. Though levels of CD14 (monocyte-derived) microparticles in patient plasma were not significantly increased, increased levels of CD14 and tissue factor positive microparticles were observed in patients. Levels of microparticles that stained for CD105 and CD144 showed a positive correlation with IgG (R = 0.60, p=0.006) and IgM anti-beta2-glycoprotein I antibodies (R=0.58, p=0.006). The elevation of endothelial and platelet derived microparticles in patients with APS and their correlation with anti-β2-glycoprotein I antibodies suggests a chronic state of vascular cell activation in these individuals and an important role for β2-glycoprotein I in development of the pro-thrombotic state associated with antiphospholipid antibodies. PMID:25467081

Isolation and genome-wide expression and methylation characterization of CD31+ cells from normal and malignant human prostate tissue

PubMed Central

Luo, Wei; Hu, Qiang; Wang, Dan; Deeb, Kristin K.; Ma, Yingyu; Morrison, Carl D.; Liu, Song; Johnson, Candace S.; Trump, Donald L.

2013-01-01

Endothelial cells (ECs) are an important component involved in the angiogenesis. Little is known about the global gene expression and epigenetic regulation in tumor endothelial cells. The identification of gene expression and epigenetic difference between human prostate tumor-derived endothelial cells (TdECs) and those in normal tissues may uncover unique biological features of TdEC and facilitate the discovery of new anti-angiogenic targets. We established a method for isolation of CD31+ endothelial cells from malignant and normal prostate tissues obtained at prostatectomy. TdECs and normal-derived ECs (NdECs) showed >90% enrichment in primary culture and demonstrated microvascular endothelial cell characteristics such as cobblestone morphology in monolayer culture, diI-acetyl-LDL uptake and capillary-tube like formation in Matrigel®. In vitro primary cultures of ECs maintained expression of endothelial markers such as CD31, von Willebrand factor, intercellular adhesion molecule, vascular endothelial growth factor receptor 1, and vascular endothelial growth factor receptor 2. We then conducted a pilot study of transcriptome and methylome analysis of TdECs and matched NdECs from patients with prostate cancer. We observed a wide spectrum of differences in gene expression and methylation patterns in endothelial cells, between malignant and normal prostate tissues. Array-based expression and methylation data were validated by qRT-PCR and bisulfite DNA pyrosequencing. Further analysis of transcriptome and methylome data revealed a number of differentially expressed genes with loci whose methylation change is accompanied by an inverse change in gene expression. Our study demonstrates the feasibility of isolation of ECs from histologically normal prostate and prostate cancer via CD31+ selection. The data, although preliminary, indicates that there exist widespread differences in methylation and transcription between TdECs and NdECs. Interestingly, only a small proportion of perturbed genes were overlapped between American (AA) and Caucasian American (CA) patients with prostate cancer. Our study indicates that identifying gene expression and/or epigenetic differences between TdECs and NdECs may provide us with new anti-angiogenic targets. Future studies will be required to further characterize the isolated ECs and determine the biological features that can be exploited in the prognosis and therapy of prostate cancer. PMID:23978847

Breast Angiosarcoma: Case Series and Expression of Vascular Endothelial Growth Factor

PubMed Central

Brar, Rondeep; West, Robert; Witten, Daniela; Raman, Bhargav; Jacobs, Charlotte; Ganjoo, Kristen

2009-01-01

Purpose Angiosarcoma of the breast is a rare, malignant tumor for which little is known regarding prognostic indicators and optimal therapeutic regimens. To address this issue, we performed a retrospective analysis of breast angiosarcoma cases seen at Stanford University along with immunohistochemical analysis for markers of angiogenesis. Methods Breast angiosarcoma cases seen between 1980 and 2008 were examined. Viable tissue blocks were analyzed for expression of vascular endothelial growth factor and its receptors. Results A total of 16 cases were identified. Data was collected regarding epidemiology, treatment, response rates, disease-free survival, and the use of various imaging modalities. Five tissue blocks remained viable for immunohistochemical analysis. Vascular endothelial growth factor-A was positively expressed in 3 of these samples. Conclusion Angiosarcoma of the breast is an aggressive malignancy with a propensity for both local recurrence and distant metastases. Angiogenesis inhibition may represent a novel therapeutic modality in this rare, vascular malignancy. PMID:20737044

Canine splenic haemangiosarcoma: influence of metastases, chemotherapy and growth pattern on post-splenectomy survival and expression of angiogenic factors.

PubMed

Göritz, M; Müller, K; Krastel, D; Staudacher, G; Schmidt, P; Kühn, M; Nickel, R; Schoon, H-A

2013-07-01

Splenic haemangiosarcomas (HSAs) from 122 dogs were characterized and classified according to their patterns of growth, survival time post splenectomy, metastases and chemotherapy. The most common pattern of growth was a mixture of cavernous, capillary and solid tumour tissue. Survival time post splenectomy was independent of the growth pattern; however, it was influenced by chemotherapy and metastases. Immunohistochemical assessment of the expression of angiogenic factors (fetal liver kinase-1, angiopoietin-2, angiopoietin receptor-2 and vascular endothelial growth factor A) and conventional endothelial markers (CD31, factor VIII-related antigen) revealed variable expression, particularly in undifferentiated HSAs. Therefore, a combination of endothelial markers should be used to confirm the endothelial origin of splenic tumours. Copyright © 2012 Elsevier Ltd. All rights reserved.

[Histocompatibility of nano-hydroxyapatite/poly-co-glycolic acid tissue engineering bone modified by mesenchymal stem cells with vascular endothelial frowth factor].

PubMed

Zhang, Minglei; Wang, Dapeng; Yin, Ruofeng

2015-10-06

To explorec Histocompatibility of nano-hydroxyapatite/poly-co-glycolic acid tissue engineering bone modified by mesenchymal stem cells with vascular endothelial frowth factor transinfected. Rat bone marrow mesenchymal stem cells (BMSCs) was separated, using BMSCs as target cells, and then vascular endothelial growth factor (VEGF) gene was transfected. Composite bone marrow mesenchymal stem cells and cells transfected with nano-hydroxyapatite (HA)/polylactic-co-glycolic acid (PLGA). The composition of cell and scaffold was observed. The blank plasmid transfection was 39.1%, 40.1% in VEGF group. The cell adhesion and growth was found on the scaffold pore wall after 5 days, and the number of adherent cells in the nano-HA/PLGA composite scaffold material basically had no significant difference in both. Although the nano-HA/PLGA scaffold material is still not fully meet the requirements of the matrix material for bone tissue engineering, but good biocompatibility, structure is its rich microporous satisfaction in material mechanics, toughening, enhanced obviously. Composition scaffold with BMSCs transfected by VEGF plasmid, the ability of angiogenesis is promoted.

Platelet-independent adhesion of calcium-loaded erythrocytes to von Willebrand factor

PubMed Central

Bierings, Ruben; Meems, Henriet; Mul, Frederik P. J.; Geerts, Dirk; Vlaar, Alexander P. J.; Voorberg, Jan; Hordijk, Peter L.

2017-01-01

Adhesion of erythrocytes to endothelial cells lining the vascular wall can cause vaso-occlusive events that impair blood flow which in turn may result in ischemia and tissue damage. Adhesion of erythrocytes to vascular endothelial cells has been described in multiple hemolytic disorders, especially in sickle cell disease, but the adhesion of normal erythrocytes to endothelial cells has hardly been described. It was shown that calcium-loaded erythrocytes can adhere to endothelial cells. Because sickle erythrocyte adhesion to ECs can be enhanced by ultra-large von Willebrand factor multimers, we investigated whether calcium loading of erythrocytes could promote binding to endothelial cells via ultra-large von Willebrand factor multimers. We used (immunofluorescent) live-cell imaging of washed erythrocytes perfused over primary endothelial cells at venular flow rate. Using this approach, we show that calcium-loaded erythrocytes strongly adhere to histamine-stimulated primary human endothelial cells. This adhesion is mediated by ultra-large von Willebrand factor multimers. Von Willebrand factor knockdown or ADAMTS13 cleavage abolished the binding of erythrocytes to activated endothelial cells under flow. Platelet depletion did not interfere with erythrocyte binding to von Willebrand factor. Our results reveal platelet-independent adhesion of calcium-loaded erythrocytes to endothelium-derived von Willebrand factor. Erythrocyte adhesion to von Willebrand factor may be particularly relevant for venous thrombosis, which is characterized by the formation of erythrocyte-rich thrombi. PMID:28249049

Phloretin suppresses thrombin-mediated leukocyte-platelet-endothelial interactions.

PubMed

Kim, Min Soo; Park, Sin-Hye; Han, Seon-Young; Kim, Yun-Ho; Lee, Eun-Jung; Yoon Park, Jung Han; Kang, Young-Hee

2014-04-01

Thrombin playing a pivotal role in coagulation cascade may influence the onset and progression of atherosclerosis as a pro-inflammatory mediator. This study investigated whether phloretin found in apple tree leaves, severed a linkage between thrombosis and atherosclerosis by thrombin. Human endothelial cells were pre-treated with 1-20 μM phloretin and stimulated with 10 U/mL thrombin. Phloretin attenuated adhesion of THP-1 monocytes and platelets to thrombin-inflamed endothelial cells with concurrent inhibition of protease-activated receptor (PAR-1) induction. The thrombin induction of endothelial CD40, endothelial integrin β3 and P-selectin, and monocytic CD40L was dampened by phloretin. Additionally, phloretin inhibited monocyte secretion of MCP-1, IL-6 and IL-8 responsible for pro-inflammatory activity of thrombin inducing endothelial CD40. The monocyte COX-2 induction and PGE2 secretion due to thrombin were down-regulated by phloretin, deterring endothelial CD40 expression. Thrombin promoted production of PAI-1 and tissue factor in monocytes was attenuated by phloretin through blocking PAR-1 and CD40. Thrombin up-regulated the induction of endothelial connective tissue growth factor independent of PAR-1 activation, which was reversed by phloretin. Phloretin disturbed tethering and stable adhesion of monocytes and platelets onto endothelium during increased thrombosis by thrombin. Phloretin would be a potent agent preventing thrombosis and atherosclerosis. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High-density lipoprotein from patients with coronary heart disease loses anti-thrombotic effects on endothelial cells: impact on arterial thrombus formation.

PubMed

Holy, Erik W; Besler, Christian; Reiner, Martin F; Camici, Giovanni G; Manz, Jasmin; Beer, Jürg H; Lüscher, Thomas F; Landmesser, Ulf; Tanner, Felix C

2014-11-01

Thrombus formation is determined by the balance between pro- thrombotic mediators and anti-thrombotic factors.High-density lipoprotein (HDL) from healthy subjects exerts anti-thrombotic properties. Whether this is also the case for HDL from patients with stable coronary heart disease (CHD) or acute coronary syndrome (ACS) is unknown.In human aortic endothelial cells in culture,HDL (50 µg/ml) from healthy subjects (HS) inhibited thrombin-induced tissue factor (TF) expression and activity, while HDL (50 µg/ml) from CHD and ACS patients did not. Similarly, only healthy HDL increased endothelial tissue factor pathway inhibitor (TFPI) expression and tissue plasminogen activator (tPA) release, while HDL from CHD and ACS patients had no effect. Healthy HDL inhibited thrombin-induced plasminogen activator inhibitor type 1 (PAI-1) expression, while HDL from ACS patients enhanced endothelial PAI-1 expression. Inhibition of nitric oxide (NO) formation with L-NAME (100 µmol/l) abolished the anti-thrombotic effects of healthy HDL on TF, TFPI, and tPA expression. The exogenous nitric oxide donor, DETANO, mimicked the effects of healthy HDL and counterbalanced the loss of anti-thrombotic effects of HDL from CHD and ACS patients in endothelial cells. In line with this observation, healthy HDL, in contrast to HDL from CHD and ACS patients, increased endothelial NO production. In the laser-injured carotid artery of the mouse, thrombus formation was delayed in animals treated with healthy HDL compared with mice treated with vehicle or HDL from patients with CHD or ACS. In conclusion, HDL from CHD and ACS patients loses the ability of healthy HDL to suppress TF and to increase TFPI and t-PA and instead enhances PAI-1 and arterial thrombus formation.

Air Pollution Upregulates Endothelial Cell Procoagulant Activity Via Ultrafine Particle-Induced Oxidant Signaling and Tissue Factor Expression

EPA Science Inventory

Air pollution exposure is associated with cardiovascular events triggered by clot formation. Endothelial activation and initiation of coagulation are pathophysiological mechanisms that could link inhaled air pollutants to vascular events. Here we investigated the underlying mecha...

Soluble tissue factor has unique angiogenic activities that selectively promote migration and differentiation but not proliferation of endothelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

He Yingbo; Chang Guodong; Zhan Shunli

2008-06-06

The level of circulating tissue factor (TF) is up-regulated in human angiogenesis-related malignancies. However, whether circulating TF has angiogenic activities has not been determined. Soluble TF (sTF) is the main domain of circulating TF. Here, using cell migration, wound healing, and tubule formation assays, human recombinant sTF was found to significantly promote the migration and differentiation of endothelial cells. The stress fiber formation and rearrangement induced by sTF observed through immunofluorescence microscope may be responsible for the stimulatory migration effect of sTF. Nevertheless, sTF had no effects on endothelial cell proliferation. Interestingly, sTF can be internalized by endothelial cells, whichmore » implies a novel mechanism for sTF in angiogenesis. These results suggest that sTF has unique angiogenic activities and may serve as a potential therapeutic target to treat diseases associated with angiogenesis such as cancer and rheumatoid arthritis.« less

Aging impairs transcriptional regulation of vascular endothelial growth factor in human microvascular endothelial cells: implications for angiogenesis and cell survival.

PubMed

Ahluwalia, A; Jones, M K; Szabo, S; Tarnawski, A S

2014-04-01

In some tissues, aging impairs angiogenesis and reduces expression of vascular endothelial growth factor A (VEGF), a fundamental regulator of angiogenesis. We previously examined angiogenesis in aging and young gastric mucosa in vivo and in vitro and showed that an imbalance between expressions of VEGF (pro-angiogenic factor) and endostatin (anti-angiogenic protein) results in an aging-related impairment of angiogenesis in rats. However, the human relevance of these findings, and whether these mechanisms apply to endothelial cells derived from other tissues, is not clear. Since P-STAT3 and P-CREB are transcription factors that, in association with HIF-1α, can activate VEGF gene expression in some cells (e.g., liver cancer cells, vascular smooth muscle cells), we examined the expression of these two proteins in human dermal microvascular endothelial cells (HMVECs) derived from aging and neonatal individuals. We examined and quantified in vitro angiogenesis, expression of VEGF, P-STAT3, P-CREB and importin-α in HMVECs isolated from neonates (neonatal) and a 66 year old subject (aging). We also examined the effects of treatment with exogenous VEGF and endostatin on in vitro angiogenesis in these cells. Endothelial cells isolated from aging individuals had impaired angiogenesis (vs. neonatal endothelial cells) and reduced expression of VEGF mRNA and protein. Aged HMVECs also had reduced importin-α expression, and reduced expression and nuclear translocation of P-STAT3 and P-CREB. Reduced VEGF gene expression in aged HMVECs strongly correlated with the decreased levels of P-STAT3, P-CREB and importin-α in these cells. Our study clearly demonstrates that endothelial cells from aging individuals have impaired angiogenesis and reduced expression of VEGF likely due to impaired nuclear transport of P-STAT3 and P-CREB transcription factors in these cells.

Proton Pump Inhibitors Decrease Soluble fms-Like Tyrosine Kinase-1 and Soluble Endoglin Secretion, Decrease Hypertension, and Rescue Endothelial Dysfunction.

PubMed

Onda, Kenji; Tong, Stephen; Beard, Sally; Binder, Natalie; Muto, Masanaga; Senadheera, Sevvandi N; Parry, Laura; Dilworth, Mark; Renshall, Lewis; Brownfoot, Fiona; Hastie, Roxanne; Tuohey, Laura; Palmer, Kirsten; Hirano, Toshihiko; Ikawa, Masahito; Kaitu'u-Lino, Tu'uhevaha; Hannan, Natalie J

2017-03-01

Preeclampsia is a severe complication of pregnancy. Antiangiogenic factors soluble fms-like tyrosine kinase-1 (sFlt-1) and soluble endoglin are secreted in excess from the placenta, causing hypertension, endothelial dysfunction, and multiorgan injury. Oxidative stress and vascular inflammation exacerbate the endothelial injury. A drug that can block these pathophysiological steps would be an attractive treatment option. Proton pump inhibitors (PPIs) are safe in pregnancy where they are prescribed for gastric reflux. We performed functional studies on primary human tissues and animal models to examine the effects of PPIs on sFlt-1 and soluble endoglin secretion, vessel dilatation, blood pressure, and endothelial dysfunction. PPIs decreased sFlt-1 and soluble endoglin secretion from trophoblast, placental explants from preeclamptic pregnancies, and endothelial cells. They also mitigated tumor necrosis factor-α-induced endothelial dysfunction: PPIs blocked endothelial vascular cell adhesion molecule-1 expression, leukocyte adhesion to endothelium, and disruption of endothelial tube formation. PPIs decreased endothelin-1 secretion and enhanced endothelial cell migration. Interestingly, the PPI esomeprazole vasodilated maternal blood vessels from normal pregnancies and cases of preterm preeclampsia, but its vasodilatory effects were lost when the vessels were denuded of their endothelium. Esomeprazole decreased blood pressure in a transgenic mouse model where human sFlt-1 was overexpressed in placenta. PPIs upregulated endogenous antioxidant defenses and decreased cytokine secretion from placental tissue and endothelial cells. We have found that PPIs decrease sFlt-1 and soluble endoglin secretion and endothelial dysfunction, dilate blood vessels, decrease blood pressure, and have antioxidant and anti-inflammatory properties. They have therapeutic potential for preeclampsia and other diseases where endothelial dysfunction is involved. © 2017 American Heart Association, Inc.

Ten-fold augmentation of endothelial uptake of vascular endothelial growth factor with ultrasound after systemic administration

NASA Technical Reports Server (NTRS)

Mukherjee, D.; Wong, J.; Griffin, B.; Ellis, S. G.; Porter, T.; Sen, S.; Thomas, J. D.

2000-01-01

OBJECTIVES: In this study, the feasibility of delivering and enhancing the uptake of vascular endothelial growth factor (VEGF) into the intact endothelium by using ultrasound (US) facilitation was determined. BACKGROUND: A limitation of tissue-targeted drug delivery is the need for direct arterial cannulation. We postulate a mechanism by which agents injected intravenously may be targeted to a tissue using US and ultrasonic contrast agents. METHODS: We used a rat model to test the ability of US and an ultrasonic contrast agent perflurocarbon exposed sonicated dextrose albumin (PESDA) to increase uptake of VEGF in the myocardium. Continuous wave Doppler US (0.6 W/cm2 at 1 MHz for 15 min) was applied to the chest wall overlying the myocardium during intravenous injection with either VEGF (100 microg/kg) alone or a combination of VEGF and PESDA (0.1%). Control rats had VEGF infused without US or PESDA. The VEGF uptake was measured quantitatively in the heart, lung, liver and kidneys by enzyme-linked immunosorbent assay (ng/g of tissue) and morphologically by fluorescence microscopy. RESULTS: There was an eight-fold increase in VEGF uptake in the heart by US alone (16.86 +/- 1.56 vs. 2.11 +/- 0.953 ng/g of tissue, p < 0.0001) and a 13-fold increase with US + PESDA (26.78 +/- 2.88 vs. 2.11 +/- 0.953 ng/g of tissue, p < 0.0001) compared with control rats. Fluorescence microscopy revealed deposition of VEGF in the endothelium of small intramyocardial arterioles. CONCLUSIONS: These results show a marked increase in endothelial VEGF uptake with US and US + PESDA. Thus, US may be used to augment endothelial VEGF uptake 10-fold to 13-fold.

Priming Dental Pulp Stem Cells With Fibroblast Growth Factor-2 Increases Angiogenesis of Implanted Tissue-Engineered Constructs Through Hepatocyte Growth Factor and Vascular Endothelial Growth Factor Secretion.

PubMed

Gorin, Caroline; Rochefort, Gael Y; Bascetin, Rumeyza; Ying, Hanru; Lesieur, Julie; Sadoine, Jérémy; Beckouche, Nathan; Berndt, Sarah; Novais, Anita; Lesage, Matthieu; Hosten, Benoit; Vercellino, Laetitia; Merlet, Pascal; Le-Denmat, Dominique; Marchiol, Carmen; Letourneur, Didier; Nicoletti, Antonino; Vital, Sibylle Opsahl; Poliard, Anne; Salmon, Benjamin; Muller, Laurent; Chaussain, Catherine; Germain, Stéphane

2016-03-01

Tissue engineering strategies based on implanting cellularized biomaterials are promising therapeutic approaches for the reconstruction of large tissue defects. A major hurdle for the reliable establishment of such therapeutic approaches is the lack of rapid blood perfusion of the tissue construct to provide oxygen and nutrients. Numerous sources of mesenchymal stem cells (MSCs) displaying angiogenic potential have been characterized in the past years, including the adult dental pulp. Establishment of efficient strategies for improving angiogenesis in tissue constructs is nevertheless still an important challenge. Hypoxia was proposed as a priming treatment owing to its capacity to enhance the angiogenic potential of stem cells through vascular endothelial growth factor (VEGF) release. The present study aimed to characterize additional key factors regulating the angiogenic capacity of such MSCs, namely, dental pulp stem cells derived from deciduous teeth (SHED). We identified fibroblast growth factor-2 (FGF-2) as a potent inducer of the release of VEGF and hepatocyte growth factor (HGF) by SHED. We found that FGF-2 limited hypoxia-induced downregulation of HGF release. Using three-dimensional culture models of angiogenesis, we demonstrated that VEGF and HGF were both responsible for the high angiogenic potential of SHED through direct targeting of endothelial cells. In addition, FGF-2 treatment increased the fraction of Stro-1+/CD146+ progenitor cells. We then applied in vitro FGF-2 priming to SHED before encapsulation in hydrogels and in vivo subcutaneous implantation. Our results showed that FGF-2 priming is more efficient than hypoxia at increasing SHED-induced vascularization compared with nonprimed controls. Altogether, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both HGF and VEGF. ©AlphaMed Press.

Neuropilin2 expressed in gastric cancer endothelial cells increases the proliferation and migration of endothelial cells in response to VEGF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Woo Ho; Lee, Sun Hee; Jung, Myung Hwan

2009-08-01

The structure and characteristics of the tumor vasculature are known to be different from those of normal vessels. Neuropilin2 (Nrp2), which is expressed in non-endothelial cell types, such as neuronal or cancer cells, functions as a receptor for both semaphorin and vascular endothelial growth factor (VEGF). After isolating tumor and normal endothelial cells from advanced gastric cancer tissue and normal gastric mucosa tissues, respectively, we identified genes that were differentially expressed in gastric tumor endothelial (TEC) and normal endothelial cells (NEC) using DNA oligomer chips. Using reverse transcriptase-PCR, we confirmed the chip results by showing that Nrp2 gene expression ismore » significantly up-regulated in TEC. Genes that were found to be up-regulated in TEC were also observed to be up-regulated in human umbilical vein endothelial cells (HUVECs) that were co-cultured with gastric cancer cells. In addition, HUVECs co-cultured with gastric cancer cells showed an increased reactivity to VEGF-induced proliferation and migration. Moreover, overexpression of Nrp2 in HUVECs significantly enhanced the proliferation and migration induced by VEGF. Observation of an immunohistochemical analysis of various human tumor tissue arrays revealed that Nrp2 is highly expressed in the tumor vessel lining and to a lesser extent in normal tissue microvessels. From these results, we suggest that Nrp2 may function to increase the response to VEGF, which is more significant in TEC than in NEC given the differential expression, leading to gastric TEC with aggressive angiogenesis phenotypes.« less

Submacular hemorrhage in neovascular age-related macular degeneration: A synthesis of the literature.

PubMed

Stanescu-Segall, Dinu; Balta, Florian; Jackson, Timothy L

2016-01-01

Large submacular hemorrhage, an uncommon manifestation of neovascular age-related macular degeneration, may also occur with idiopathic polypoidal choroidal vasculopathy. Submacular hemorrhage damages photoreceptors owing to iron toxicity, fibrin meshwork contraction, and reduced nutrient flux, with subsequent macular scarring. Clinical and experimental studies support prompt treatment, as tissue damage can occur within 24 hours. Without treatment the natural history is poor, with a mean final visual acuity (VA) of 20/1600. Reported treatments include retinal pigment epithelial patch, macular translocation, pneumatic displacement, intravitreal or subretinal tissue plasminogen activator, intravitreal anti-vascular endothelial growth factor (VEGF) drugs, and combinations thereof. In the absence of comparative studies, we combined eligible studies to assess the VA change before and after each treatment option. The greatest improvement occurred after combined pars plana vitrectomy, subretinal tissue plasminogen activator, intravitreal gas, and anti-vascular endothelial growth factor treatment, with VA improving from 20/1000 to 20/400. The best final VA occurred using combined intravitreal tissue plasminogen activator, gas, and anti-vascular endothelial growth factor therapy, with VA improving from 20/200 to 20/100. Both treatments had an acceptable safety profile, but most studies were small, and larger randomized controlled trials are needed to determine both safety and efficacy. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

Porcine endothelium induces DNA-histone complex formation in human whole blood: a harmful effect of histone on coagulation and endothelial activation.

PubMed

Yoo, Hyun Ju; Kim, Ji-Eun; Gu, Ja Yoon; Lee, Sae Bom; Lee, Hyun Joo; Hwang, Ho Young; Hwang, Yoohwa; Kim, Young Tae; Kim, Hyun Kyung

2016-11-01

Neutrophils play a role in xenograft rejection. When neutrophils are stimulated, they eject the DNA-histone complex into the extracellular space, called neutrophil extracellular traps (NET). We investigated whether NET formation actively occurs in the xenograft and contributes to coagulation and endothelial activation. Human whole blood was incubated with porcine aortic endothelial cells (pEC) from wild-type or α1,3-galactosyltransferase gene-knockout (GTKO) pigs. In the supernatant plasma from human blood, the level of the DNA-histone complex was measured by ELISA, and thrombin generation was measured using a calibrated automated thrombogram. Histone-induced tissue factor and adhesion molecule expression were measured by flow cytometry. pEC from both wild-type and GTKO pigs significantly induced DNA-histone complex formation in human whole blood. The DNA-histone complex produced shortened the thrombin generation time and clotting time. Histone alone dose-dependently induced tissue factor and adhesion molecule expression in pEC. Aurintricarboxylic acid pretreatment partially inhibited pEC-induced DNA-histone complex formation. DNA-histone complex actively generated upon xenotransplantation is a novel target to inhibit coagulation and endothelial activation. To prevent tissue factor and adhesion molecule expression, a strategy to block soluble histone may be required in xenotransplantation. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effects of vitamin D(3)-binding protein-derived macrophage activating factor (GcMAF) on angiogenesis.

PubMed

Kanda, Shigeru; Mochizuki, Yasushi; Miyata, Yasuyoshi; Kanetake, Hiroshi; Yamamoto, Nobuto

2002-09-04

The vitamin D(3)-binding protein (Gc protein)-derived macrophage activating factor (GcMAF) activates tumoricidal macrophages against a variety of cancers indiscriminately. We investigated whether GcMAF also acts as an antiangiogenic factor on endothelial cells. The effects of GcMAF on angiogenic growth factor-induced cell proliferation, chemotaxis, and tube formation were examined in vitro by using cultured endothelial cells (murine IBE cells, porcine PAE cells, and human umbilical vein endothelial cells [HUVECs]) and in vivo by using a mouse cornea micropocket assay. Blocking monoclonal antibodies to CD36, a receptor for the antiangiogenic factor thrombospondin-1, which is also a possible receptor for GcMAF, were used to investigate the mechanism of GcMAF action. GcMAF inhibited the endothelial cell proliferation, chemotaxis, and tube formation that were all stimulated by fibroblast growth factor-2 (FGF-2), vascular endothelial growth factor-A, or angiopoietin 2. FGF-2-induced neovascularization in murine cornea was also inhibited by GcMAF. Monoclonal antibodies against murine and human CD36 receptor blocked the antiangiogenic action of GcMAF on the angiogenic factor stimulation of endothelial cell chemotaxis. In addition to its ability to activate tumoricidal macrophages, GcMAF has direct antiangiogenic effects on endothelial cells independent of tissue origin. The antiangiogenic effects of GcMAF may be mediated through the CD36 receptor.

Treating fat grafts with human endothelial progenitor cells promotes their vascularization and improves their survival in diabetes mellitus.

PubMed

Hamed, Saher; Ben-Nun, Ohad; Egozi, Dana; Keren, Aviad; Malyarova, Nastya; Kruchevsky, Danny; Gilhar, Amos; Ullmann, Yehuda

2012-10-01

Bone marrow-derived endothelial progenitor cells are required for vascularization of a fat graft to form a functional microvasculature within the graft and to facilitate its integration into the surrounding tissues. Organ transplantation carries a high risk of graft loss and rejection in patients with diabetes mellitus because endothelial progenitor cell function is impaired. The authors investigated the influence of endothelial progenitor cell treatment on the phenotype and survival of human fat grafts in immunocompromised mice with experimentally induced diabetes mellitus. The authors injected 1 ml of human fat tissue into the scalps of 14 nondiabetic and 28 diabetic immunocompromised mice, and then treated some of the grafts with endothelial progenitor cells that was isolated from the blood of a human donor. The phenotype of the endothelial progenitor cell-treated fat grafts from the 14 diabetic mice was compared with that of the untreated fat grafts from 14 nondiabetic and 14 diabetic mice, 18 days and 15 weeks after fat transplantation. Determination of graft phenotype included measurements of weight and volume, vascular endothelial growth factor levels, vascular endothelial growth factor receptor-2, endothelial nitric oxide synthase, and caspase 3 expression levels, and histologic analysis of the extent of vascularization. The untreated grafts from the diabetic mice were fully resorbed 15 weeks after fat transplantation. The phenotype of endothelial progenitor cell-treated fat grafts from the diabetic mice was similar to that of the untreated fat grafts from the nondiabetic mice. Endothelial progenitor cell treatment of transplanted fat can increase the survival of a fat graft by inducing its vascularization and decreasing the extent of apoptosis.

Influence of epidermal growth factor (EGF) and hydrocortisone on the co-culture of mature adipocytes and endothelial cells for vascularized adipose tissue engineering.

PubMed

Huber, Birgit; Czaja, Alina Maria; Kluger, Petra Juliane

2016-05-01

The composition of vascularized adipose tissue is still an ongoing challenge as no culture medium is available to supply adipocytes and endothelial cells appropriately. Endothelial cell medium is typically supplemented with epidermal growth factor (EGF) as well as hydrocortisone (HC). The effect of EGF on adipocytes is discussed controversially. Some studies say it inhibits adipocyte differentiation while others reported of improved adipocyte lipogenesis. HC is known to have lipolytic activities, which might result in mature adipocyte dedifferentiation. In this study, we evaluated the influence of EGF and HC on the co-culture of endothelial cells and mature adipocytes regarding their cell morphology and functionality. We showed in mono-culture that high levels of HC promoted dedifferentiation and proliferation of mature adipocytes, whereas EGF seemed to have no negative influence. Endothelial cells kept their typical cobblestone morphology and showed a proliferation rate comparable to the control independent of EGF and HC concentration. In co-culture, HC promoted dedifferentiation of mature adipocytes, which was shown by a higher glycerol release. EGF had no negative impact on adipocyte morphology. No negative impact on endothelial cell morphology and functionality could be seen with reduced EGF and HC supplementation in co-culture with mature adipocytes. Taken together, our results demonstrate that reduced levels of HC are needed for co-culturing mature adipocytes and endothelial cells. In co-culture, EGF had no influence on mature adipocytes. Therefore, for the composition of vascularized adipose tissue constructs, the media with low levels of HC and high or low levels of EGF can be used. © 2016 International Federation for Cell Biology.

Vascular Endothelial Growth Factor (VEGF) and Platelet (PF-4) Factor 4 Inputs Modulate Human Microvascular Endothelial Signaling in a Three-Dimensional Matrix Migration Context*

PubMed Central

Hang, Ta-Chun; Tedford, Nathan C.; Reddy, Raven J.; Rimchala, Tharathorn; Wells, Alan; White, Forest M.; Kamm, Roger D.; Lauffenburger, Douglas A.

2013-01-01

The process of angiogenesis is under complex regulation in adult organisms, particularly as it often occurs in an inflammatory post-wound environment. As such, there are many impacting factors that will regulate the generation of new blood vessels which include not only pro-angiogenic growth factors such as vascular endothelial growth factor, but also angiostatic factors. During initial postwound hemostasis, a large initial bolus of platelet factor 4 is released into localized areas of damage before progression of wound healing toward tissue homeostasis. Because of its early presence and high concentration, the angiostatic chemokine platelet factor 4, which can induce endothelial anoikis, can strongly affect angiogenesis. In our work, we explored signaling crosstalk interactions between vascular endothelial growth factor and platelet factor 4 using phosphotyrosine-enriched mass spectrometry methods on human dermal microvascular endothelial cells cultured under conditions facilitating migratory sprouting into collagen gel matrices. We developed new methods to enable mass spectrometry-based phosphorylation analysis of primary cells cultured on collagen gels, and quantified signaling pathways over the first 48 h of treatment with vascular endothelial growth factor in the presence or absence of platelet factor 4. By observing early and late signaling dynamics in tandem with correlation network modeling, we found that platelet factor 4 has significant crosstalk with vascular endothelial growth factor by modulating cell migration and polarization pathways, centered around P38α MAPK, Src family kinases Fyn and Lyn, along with FAK. Interestingly, we found EphA2 correlational topology to strongly involve key migration-related signaling nodes after introduction of platelet factor 4, indicating an influence of the angiostatic factor on this ambiguous but generally angiogenic signal in this complex environment. PMID:24023389

Epoxyeicosanoids promote organ and tissue regeneration.

PubMed

Panigrahy, Dipak; Kalish, Brian T; Huang, Sui; Bielenberg, Diane R; Le, Hau D; Yang, Jun; Edin, Matthew L; Lee, Craig R; Benny, Ofra; Mudge, Dayna K; Butterfield, Catherine E; Mammoto, Akiko; Mammoto, Tadanori; Inceoglu, Bora; Jenkins, Roger L; Simpson, Mary A; Akino, Tomoshige; Lih, Fred B; Tomer, Kenneth B; Ingber, Donald E; Hammock, Bruce D; Falck, John R; Manthati, Vijaya L; Kaipainen, Arja; D'Amore, Patricia A; Puder, Mark; Zeldin, Darryl C; Kieran, Mark W

2013-08-13

Epoxyeicosatrienoic acids (EETs), lipid mediators produced by cytochrome P450 epoxygenases, regulate inflammation, angiogenesis, and vascular tone. Despite pleiotropic effects on cells, the role of these epoxyeicosanoids in normal organ and tissue regeneration remains unknown. EETs are produced predominantly in the endothelium. Normal organ and tissue regeneration require an active paracrine role of the microvascular endothelium, which in turn depends on angiogenic growth factors. Thus, we hypothesize that endothelial cells stimulate organ and tissue regeneration via production of bioactive EETs. To determine whether endothelial-derived EETs affect physiologic tissue growth in vivo, we used genetic and pharmacological tools to manipulate endogenous EET levels. We show that endothelial-derived EETs play a critical role in accelerating tissue growth in vivo, including liver regeneration, kidney compensatory growth, lung compensatory growth, wound healing, corneal neovascularization, and retinal vascularization. Administration of synthetic EETs recapitulated these results, whereas lowering EET levels, either genetically or pharmacologically, delayed tissue regeneration, demonstrating that pharmacological modulation of EETs can affect normal organ and tissue growth. We also show that soluble epoxide hydrolase inhibitors, which elevate endogenous EET levels, promote liver and lung regeneration. Thus, our observations indicate a central role for EETs in organ and tissue regeneration and their contribution to tissue homeostasis.

Vascular tissue engineering by computer-aided laser micromachining.

PubMed

Doraiswamy, Anand; Narayan, Roger J

2010-04-28

Many conventional technologies for fabricating tissue engineering scaffolds are not suitable for fabricating scaffolds with patient-specific attributes. For example, many conventional technologies for fabricating tissue engineering scaffolds do not provide control over overall scaffold geometry or over cell position within the scaffold. In this study, the use of computer-aided laser micromachining to create scaffolds for vascular tissue networks was investigated. Computer-aided laser micromachining was used to construct patterned surfaces in agarose or in silicon, which were used for differential adherence and growth of cells into vascular tissue networks. Concentric three-ring structures were fabricated on agarose hydrogel substrates, in which the inner ring contained human aortic endothelial cells, the middle ring contained HA587 human elastin and the outer ring contained human aortic vascular smooth muscle cells. Basement membrane matrix containing vascular endothelial growth factor and heparin was to promote proliferation of human aortic endothelial cells within the vascular tissue networks. Computer-aided laser micromachining provides a unique approach to fabricate small-diameter blood vessels for bypass surgery as well as other artificial tissues with complex geometries.

Low intensity shear stress increases endothelial ELR+ CXC chemokine production via a focal adhesion kinase-p38{beta} MAPK-NF-{kappa}B pathway.

PubMed

Shaik, Sadiq S; Soltau, Thomas D; Chaturvedi, Gaurav; Totapally, Balagangadhar; Hagood, James S; Andrews, William W; Athar, Mohammad; Voitenok, Nikolai N; Killingsworth, Cheryl R; Patel, Rakesh P; Fallon, Michael B; Maheshwari, Akhil

2009-02-27

CXC chemokines with a glutamate-leucine-arginine (ELR) tripeptide motif (ELR(+) CXC chemokines) play an important role in leukocyte trafficking into the tissues. For reasons that are not well elucidated, circulating leukocytes are recruited into the tissues mainly in small vessels such as capillaries and venules. Because ELR(+) CXC chemokines are important mediators of endothelial-leukocyte interaction, we compared chemokine expression by microvascular and aortic endothelium to investigate whether differences in chemokine expression by various endothelial types could, at least partially, explain the microvascular localization of endothelial-leukocyte interaction. Both in vitro and in vivo models indicate that ELR(+) CXC chemokine expression is higher in microvascular endothelium than in aortic endothelial cells. These differences can be explained on the basis of the preferential activation of endothelial chemokine production by low intensity shear stress. Low shear activated endothelial ELR(+) CXC chemokine production via cell surface heparan sulfates, beta(3)-integrins, focal adhesion kinase, the mitogen-activated protein kinase p38beta, mitogen- and stress-associated protein kinase-1, and the transcription factor.

Expression and distribution of endocan in human tissues.

PubMed

Zhang, S M; Zuo, L; Zhou, Q; Gui, S Y; Shi, R; Wu, Q; Wei, W; Wang, Y

2012-04-01

Endocan is a novel human endothelial cell specific molecule. Its expression is regulated by cytokines and vascular endothelial growth factor (VEGF). The distribution of endocan in normal human tissues, however, remains unclear. We examined the expression of endocan in normal human tissue using immunohistochemical stains. Endocan was expressed in actively proliferative or neogeneic tissues and cells such as glandular tissues, endothelium of neovasculature, bronchial epithelium, germinal centers of lymph nodes etc. Endocan was not present in silent or resting tissues or cells such as endothelium of great arteries and spleen etc. Our findings suggest that endocan may act as a marker for angiogenesis or oncogenesis and could be regarded as a candidate gene for inflammatory tissue, neoplasia, tumor development and metastasis. The expression level of endocan may assist early diagnosis and prognosis of some tumors.

Vascular endothelial growth factor is upregulated by l-dopa in the parkinsonian brain: implications for the development of dyskinesia

PubMed Central

Francardo, Veronica; Lindgren, Hanna S.; Sillivan, Stephanie E.; O’Sullivan, Sean S.; Luksik, Andrew S.; Vassoler, Fair M.; Lees, Andrew J.; Konradi, Christine

2011-01-01

Angiogenesis and increased permeability of the blood–brain barrier have been reported to occur in animal models of Parkinson’s disease and l-dopa-induced dyskinesia, but the significance of these phenomena has remained unclear. Using a validated rat model of l-dopa-induced dyskinesia, this study demonstrates that chronic treatment with l-dopa dose dependently induces the expression of vascular endothelial growth factor in the basal ganglia nuclei. Vascular endothelial growth factor was abundantly expressed in astrocytes and astrocytic processes in the proximity of blood vessels. When co-administered with l-dopa, a small molecule inhibitor of vascular endothelial growth factor signalling significantly attenuated the development of dyskinesia and completely blocked the angiogenic response and associated increase in blood–brain barrier permeability induced by the treatment. The occurrence of angiogenesis and vascular endothelial growth factor upregulation was verified in post-mortem basal ganglia tissue from patients with Parkinson’s disease with a history of dyskinesia, who exhibited increased microvascular density, microvascular nestin expression and an upregulation of vascular endothelial growth factor messenger ribonucleic acid. These congruent findings in the rat model and human patients indicate that vascular endothelial growth factor is implicated in the pathophysiology of l-dopa-induced dyskinesia and emphasize an involvement of the microvascular compartment in the adverse effects of l-dopa pharmacotherapy in Parkinson’s disease. PMID:21771855

Pathophysiological consequences of VEGF-induced vascular permeability

NASA Astrophysics Data System (ADS)

Weis, Sara M.; Cheresh, David A.

2005-09-01

Although vascular endothelial growth factor (VEGF) induces angiogenesis, it also disrupts vascular barrier function in diseased tissues. Accordingly, VEGF expression in cancer and ischaemic disease has unexpected pathophysiological consequences. By uncoupling endothelial cell-cell junctions VEGF causes vascular permeability and oedema, resulting in extensive injury to ischaemic tissues after stroke or myocardial infarction. In cancer, VEGF-mediated disruption of the vascular barrier may potentiate tumour cell extravasation, leading to widespread metastatic disease. Therefore, by blocking the vascular permeability promoting effects of VEGF it may be feasible to reduce tissue injury after ischaemic disease and minimize the invasive properties of circulating tumour cells.

Angiogenesis and lymphangiogenesis are downregulated in primary breast cancer

PubMed Central

Boneberg, E-M; Legler, D F; Hoefer, M M; Öhlschlegel, C; Steininger, H; Füzesi, L; Beer, G M; Dupont-Lampert, V; Otto, F; Senn, H-J; Fürstenberger, G

2009-01-01

Background: Angiogenesis and lymphangiogenesis are considered to play key roles in tumour growth, progression and metastasis. However, targeting tumour angiogenesis in clinical trials showed only modest efficacy. We therefore scrutinised the concept of tumour angiogenesis and lymphangiogenesis by analysing the expression of crucial markers involved in these processes in primary breast cancer. Methods: We analysed the expression of angiogenic, lymphangiogenic or antiangiogenic factors, their respective receptors and specific markers for endothelial and lymphendothelial cells by quantitative real-time RT-PCR in primary breast cancer and compared the expression profiles to non-cancerous, tumour-adjacent tissues and breast tissues from healthy women. Results: We found decreased mRNA amounts of major angiogenic and lymphangiogenic factors in tumour compared to healthy tissues, whereas antiangiogenic factors were upregulated. Concomitantly, angiogenic and lymphangiogenic receptors were downregulated in breast tumours. This antiangiogenic, antilymphangiogenic microenvironment was even more pronounced in aggressive tumours and accompanied by reduced amounts of endothelial and lymphatic endothelial cell markers. Conclusion: Primary breast tumours are not a site of highly active angiogenesis and lymphangiogenesis. Selection for tumour cells that survive with minimal vascular supply may account for this observation in clinical apparent tumours. PMID:19672262

Trypsinogen 4 boosts tumor endothelial cells migration through proteolysis of tissue factor pathway inhibitor-2.

PubMed

Ghilardi, Carmen; Silini, Antonietta; Figini, Sara; Anastasia, Alessia; Lupi, Monica; Fruscio, Robert; Giavazzi, Raffaella; Bani, Maria Rosa

2015-09-29

Proteases contribute to cancer in many ways, including tumor vascularization and metastasis, and their pharmacological inhibition is a potential anticancer strategy. We report that human endothelial cells (EC) express the trypsinogen 4 isoform of the serine protease 3 (PRSS3), and lack both PRSS2 and PRSS1. Trypsinogen 4 expression was upregulated by the combined action of VEGF-A, FGF-2 and EGF, angiogenic factors representative of the tumor microenvironment. Suppression of trypsinogen 4 expression by siRNA inhibited the angiogenic milieu-induced migration of EC from cancer specimens (tumor-EC), but did not affect EC from normal tissues. We identified tissue factor pathway inhibitor-2 (TFPI-2), a matrix associated inhibitor of cell motility, as the functional target of trypsinogen 4, which cleaved TFPI-2 and removed it from the matrix put down by tumor-EC. Silencing tumor-EC for trypsinogen 4 accumulated TFPI2 in the matrix. Showing that angiogenic factors stimulate trypsinogen 4 expression, which hydrolyses TFPI-2 favoring a pro-migratory situation, our study suggests a new pathway linking tumor microenvironment signals to endothelial cell migration, which is essential for angiogenesis and blood vessel remodeling. Abolishing trypsinogen 4 functions might be an exploitable strategy as anticancer, particularly anti-vascular, therapy.

Trypsinogen 4 boosts tumor endothelial cells migration through proteolysis of tissue factor pathway inhibitor-2

PubMed Central

Ghilardi, Carmen; Silini, Antonietta; Figini, Sara; Anastasia, Alessia; Lupi, Monica; Fruscio, Robert; Giavazzi, Raffaella; Bani, MariaRosa

2015-01-01

Proteasescontribute to cancer in many ways, including tumor vascularization and metastasis, and their pharmacological inhibition is a potential anticancer strategy. We report that human endothelial cells (EC) express the trypsinogen 4 isoform of the serine protease 3 (PRSS3), and lack both PRSS2 and PRSS1. Trypsinogen 4 expression was upregulated by the combined action of VEGF-A, FGF-2 and EGF, angiogenic factors representative of the tumor microenvironment. Suppression of trypsinogen 4 expression by siRNA inhibited the angiogenic milieu-induced migration of EC from cancer specimens (tumor-EC), but did not affect EC from normal tissues. We identified tissue factor pathway inhibitor-2 (TFPI-2), a matrix associated inhibitor of cell motility, as the functional target of trypsinogen 4, which cleaved TFPI-2 and removed it from the matrix put down by tumor-EC. Silencing tumor-EC for trypsinogen 4 accumulated TFPI2 in the matrix. Showing that angiogenic factors stimulate trypsinogen 4 expression, which hydrolyses TFPI-2 favoring a pro-migratory situation, our study suggests a new pathway linking tumor microenvironment signals to endothelial cell migration, which is essential for angiogenesis and blood vessel remodeling. Abolishing trypsinogen 4 functions might be an exploitable strategy as anticancer, particularly anti-vascular, therapy. PMID:26318044

Cross talk between primary human renal tubular cells and endothelial cells in cocultures.

PubMed

Tasnim, Farah; Zink, Daniele

2012-04-15

Interactions between renal tubular epithelial cells and adjacent endothelial cells are essential for normal renal functions but also play important roles in renal disease and repair. Here, we investigated cocultures of human primary renal proximal tubular cells (HPTC) and human primary endothelial cells to address the cross talk between these cell types. HPTC showed improved proliferation, marker gene expression, and enzyme activity in cocultures. Also, the long-term maintenance of epithelia formed by HPTC was improved, which was due to the secretion of transforming growth factor-β1 and its antagonist α2-macroglobulin. HPTC induced endothelial cells to secrete increased amounts of these factors, which balanced each other functionally and only displayed in combination the observed positive effects. In addition, in the presence of HPTC endothelial cells expressed increased amounts of hepatocyte growth factor and vascular endothelial growth factor, which have well-characterized effects on renal tubular epithelial cells as well as on endothelial cells. Together, the results showed that HPTC stimulated endothelial cells to express a functionally balanced combination of various factors, which in turn improved the performance of HPTC. The results give new insights into the cross talk between renal epithelial and endothelial cells and suggest that cocultures could be also useful models for the analysis of cellular communication in renal disease and repair. Furthermore, the characterization of defined microenvironments, which positively affect HPTC, will be helpful for improving the performance of this cell type in in vitro applications including in vitro toxicology and kidney tissue engineering.

Negative effects of a high tumour necrosis factor-α concentration on human gingival mesenchymal stem cell trophism: the use of natural compounds as modulatory agents.

PubMed

Giacomelli, Chiara; Natali, Letizia; Nisi, Marco; De Leo, Marinella; Daniele, Simona; Costa, Barbara; Graziani, Filippo; Gabriele, Mario; Braca, Alessandra; Trincavelli, M Letizia; Martini, Claudia

2018-05-11

Adult mesenchymal stem cells (MSCs) play a crucial role in the maintenance of tissue homeostasis and in regenerative processes. Among the different MSC types, the gingiva-derived mesenchymal stem cells (GMSCs) have arisen as a promising tool to promote the repair of damaged tissues secreting trophic mediators that affect different types of cells involved in regenerative processes. Tumour necrosis factor (TNF)-α is one of the key mediators of inflammation that could affect tissue regenerative processes and modify the MSC properties in in-vitro applications. To date, no data have been reported on the effects of TNF-α on GMSC trophic activities and how its modulation with anti-inflammatory agents from natural sources could modulate the GMSC properties. GMSCs were isolated and characterized from healthy subjects. The effects of TNF-α were evaluated on GMSCs and on the well-being of endothelial cells. The secretion of cytokines was measured and related to the modification of GMSC-endothelial cell communication using a conditioned-medium method. The ability to modify the inflammatory response was evaluated in the presence of Ribes nigrum bud extract (RBE). TNF-α differently affected GMSC proliferation and the expression of inflammatory-related proteins (interleukin (IL)-6, IL-10, transforming growth factor (TGF)-β, and cyclooxygenase (COX)-2) dependent on its concentration. A high TNF-α concentration decreased the GMSC viability and impaired the positive cross-talk between GMSCs and endothelial cells, probably by enhancing the amount of pro-inflammatory cytokines in the GMSC secretome. RBE restored the beneficial effects of GMSCs on endothelial viability and motility under inflammatory conditions. A high TNF-α concentration decreased the well-being of GMSCs, modifying their trophic activities and decreasing endothelial cell healing. These data highlight the importance of controlling TNF-α concentrations to maintain the trophic activity of GMSCs. Furthermore, the use of natural anti-inflammatory agents restored the regenerative properties of GMSCs on endothelial cells, opening the way to the use and development of natural extracts in wound healing, periodontal regeneration, and tissue-engineering applications that use MSCs.

Tissue engineering of bladder using vascular endothelial growth factor gene-modified endothelial progenitor cells.

PubMed

Chen, Bai-Song; Xie, Hua; Zhang, Sheng-Li; Geng, Hong-Quan; Zhou, Jun-Mei; Pan, Jun; Chen, Fang

2011-12-01

This study assessed the use of vascular endothelial growth factor (VEGF) gene-modified endothelial progenitor cells (EPCs) seeded onto bladder acellular matrix grafts (BAMGs), to enhance the blood supply in tissue-engineered bladders in a porcine model. Autologous porcine peripheral EPCs were isolated, cultured, expanded, characterized, and modified with the VEGF gene using an adenovirus vector. The expression of VEGF was examined using reverse transcriptase polymerase chain reaction (RT-PCR) and an enzyme-linked immunosorbent assay (ELISA). VEGF gene modified EPCs were seeded onto BAMG and cultured for 3 days before implantation into pigs for bladder tissue engineering. A partial bladder cystectomy was performed in 12 pigs. The experimental group (6 pigs) received VEGF gene-modified EPC-seeded BAMG. The control group (6 pigs) received BAMG without seeded EPCs. The resulting tissue-engineered bladders were subject to a general and histological analysis. Microvessel density (MVD) was assessed using immunohistochemistry. The ex vivo transfection efficiency of EPCs was greater than 60%-70% when concentrated adenovirus was used. The genetically modified cells expressed both VEGF and green fluorescent protein (GFP). Scanning electron microscopy (SEM) and Masson's trichrome staining of cross sections of the cultured cells seeded to BAMG showed cell attachment and proliferation on the surface of the BAMG. Histological examination revealed bladder regeneration in a time-dependent fashion. Significant increases in MVD were observed in the experimental group, in comparison with the control group. VEGF-modified EPCs significantly enhanced neovascularization, compared with BAMG alone. These results indicate that EPCs, combined with VEGF gene therapy, may be a suitable approach for increasing blood supply in the tissue engineering of bladders. Thus, a useful strategy to achieve a tissue-engineered bladder is indicated.

Specific Accumulation of Tumor-Derived Adhesion Factor in Tumor Blood Vessels and in Capillary Tube-Like Structures of Cultured Vascular Endothelial Cells

NASA Astrophysics Data System (ADS)

Akaogi, Kotaro; Okabe, Yukie; Sato, Junji; Nagashima, Yoji; Yasumitsu, Hidetaro; Sugahara, Kazuyuki; Miyazaki, Kaoru

1996-08-01

Tumor-derived adhesion factor (TAF) was previously identified as a cell adhesion molecule secreted by human bladder carcinoma cell line EJ-1. To elucidate the physiological function of TAF, we examined its distribution in human normal and tumor tissues. Immunochemical staining with an anti-TAF monoclonal antibody showed that TAF was specifically accumulated in small blood vessels and capillaries within and adjacent to tumor nests, but not in those in normal tissues. Tumor blood vessel-specific staining of TAF was observed in various human cancers, such as esophagus, brain, lung, and stomach cancers. Double immunofluorescent staining showed apparent colocalization of TAF and type IV collagen in the vascular basement membrane. In vitro experiments demonstrated that TAF preferentially bound to type IV collagen among various extracellular matrix components tested. In cell culture experiments, TAF promoted adhesion of human umbilical vein endothelial cells to type IV collagen substrate and induced their morphological change. Furthermore, when the endothelial cells were induced to form capillary tube-like structures by type I collagen, TAF and type IV collagen were exclusively detected on the tubular structures. The capillary tube formation in vitro was prevented by heparin, which inhibited the binding of TAF to the endothelial cells. These results strongly suggest that TAF contributes to the organization of new capillary vessels in tumor tissues by modulating the interaction of endothelial cells with type IV collagen.

Upregulation of angiogenesis in oral lichen planus.

PubMed

Al-Hassiny, A; Friedlander, L T; Parachuru, V P B; Seo, B; Hussaini, H M; Rich, A M

2018-02-01

As angiogenesis is fundamental to the pathogenesis of many chronic inflammatory disorders, this study investigated the expression of various vascular markers in oral lichen planus and non-specific oral mucosal inflammatory tissues. Archival specimens of oral lichen planus (n = 15) and inflamed tissues (n = 13) were stained using immunohistochemistry with antibodies to CD34, vascular endothelial growth factor, vascular endothelial growth factor receptor and vasohibin. Nine representative sites at the epithelial-connective tissue junction and through the fibrous connective tissue were selected, and automated analysis techniques were used to determine the extent of positivity expressed as the percentage of positive cells. Significance was denoted when P < .05. The expression of pro-angiogenic factors was higher in lichen planus samples compared with inflamed controls. A higher level of CD34 was observed in the deeper parts of the connective tissue of Oral lichen planus (OLP) (P = .04), whereas VEGF and VEGFR2 expressions were higher all through the tissues (respectively, P < .02 and P < .01). The expression of the anti-angiogenic VASH1 was higher in inflamed tissue compared with lichen planus in all sites evaluated (P < .01). The findings indicate that angiogenic factors are differentially expressed in oral lichen planus compared with inflamed controls, with increased expression of pro-angiogenic factors and decreased anti-angiogenic expression. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

In Situ Detection of Anaplasma spp. by DNA Target-Primed Rolling-Circle Amplification of a Padlock Probe and Intracellular Colocalization with Immunofluorescently Labeled Host Cell von Willebrand Factor ▿

PubMed Central

Wamsley, Heather L.; Barbet, Anthony F.

2008-01-01

Endothelial cell culture and preliminary immunofluorescent staining of Anaplasma-infected tissues suggest that endothelial cells may be an in vivo nidus of mammalian infection. To investigate endothelial cells and other potentially cryptic sites of Anaplasma sp. infection in mammalian tissues, a sensitive and specific isothermal in situ technique to detect localized Anaplasma gene sequences by using rolling-circle amplification of circularizable, linear, oligonucleotide probes (padlock probes) was developed. Cytospin preparations of uninfected or Anaplasma-infected cell cultures were examined using this technique. Via fluorescence microscopy, the technique described here, and a combination of differential interference contrast microscopy and von Willebrand factor immunofluorescence, Anaplasma phagocytophilum and Anaplasma marginale were successfully localized in situ within intact cultured mammalian cells. This work represents the first application of this in situ method for the detection of a microorganism and forms the foundation for future applications of this technique to detect, localize, and analyze Anaplasma nucleotide sequences in the tissues of infected mammalian and arthropod hosts and in cell cultures. PMID:18495855

Interactions of Histophilus somni with Host Cells.

PubMed

Behling-Kelly, Erica; Rivera-Rivas, Jose; Czuprynski, Charles J

2016-01-01

Histophilus somni resides as part of the normal microflora in the upper respiratory tract of healthy cattle. From this site, the organism can make its way into the lower respiratory tract, where it is one of the important bacterial agents of the respiratory disease complex. If H. somni cells disseminate to the bloodstream, they frequently result in thrombus formation. A series of in vitro investigations have examined potential mechanisms that might contribute to such thrombus formation. Earlier work showed that H. somni can stimulate some bovine endothelial cells to undergo apoptosis. More recent studies indicate that H. somni stimulates endothelial cell tissue factor activity and disrupts intercellular junctions. The net effect is to enhance procoagulant activity on the endothelium surface and to make the endothelial monolayer more permeable to molecules, leukocytes, and perhaps H. somni cells. H. somni also activates bovine platelets, which also can enhance tissue factor activity on the endothelium surface. When exposed to H. somni, bovine neutrophils and mononuclear phagocytes form extracellular traps in vitro. Ongoing research is investigating how the interplay among endothelial cells, platelets, and leukocytes might contribute to the thrombus formation seen in infected cattle.

Systemic administration of thrombin peptide TP508 enhances VEGF-stimulated angiogenesis and attenuates effects of chronic hypoxia

PubMed Central

Olszewska-Pazdrak, Barbara; Carney, Darrell H.

2015-01-01

Revascularization of chronic wounds and ischemic tissue is attenuated by endothelial dysfunction and the inability of angiogenic factors to stimulate angiogenesis. We recently showed that TP508, a nonproteolytic thrombin peptide, increases perfusion and NO-dependent vasodilation in hearts with chronic ischemia and stimulates NO production by endothelial cells. In this study, we investigated systemic in vivo effects of TP508 on VEGF-stimulated angiogenesis in vitro using aortic explants in normoxic and hypoxic conditions. Mice were injected with saline or TP508 and 24h later aortas were removed and cultured to quantify endothelial sprouting. TP508 injection increased endothelial sprouting and potentiated the in vitro response to VEGF. Exposure of control explants to hypoxia inhibited basal and VEGF-stimulated endothelial cell sprouting. This effect of hypoxia was significantly prevented by TP508 injection. Thus, TP508 systemic administration increases responsiveness of aortic endothelial cells to VEGF and diminishes the effect of chronic hypoxia on endothelial cell sprouting. Studies using human endothelial cells in culture suggest that protective effects of TP508 during hypoxia may involve stimulation of endothelial cell NO production. These data suggest potential clinical benefit of using a combination of systemic TP508 and local VEGF as a therapy for revascularization of ischemic tissue. PMID:23594718

A Cost-Minimization Analysis of Tissue-Engineered Constructs for Corneal Endothelial Transplantation

PubMed Central

Tan, Tien-En; Peh, Gary S. L.; George, Benjamin L.; Cajucom-Uy, Howard Y.; Dong, Di; Finkelstein, Eric A.; Mehta, Jodhbir S.

2014-01-01

Corneal endothelial transplantation or endothelial keratoplasty has become the preferred choice of transplantation for patients with corneal blindness due to endothelial dysfunction. Currently, there is a worldwide shortage of transplantable tissue, and demand is expected to increase further with aging populations. Tissue-engineered alternatives are being developed, and are likely to be available soon. However, the cost of these constructs may impair their widespread use. A cost-minimization analysis comparing tissue-engineered constructs to donor tissue procured from eye banks for endothelial keratoplasty was performed. Both initial investment costs and recurring costs were considered in the analysis to arrive at a final tissue cost per transplant. The clinical outcomes of endothelial keratoplasty with tissue-engineered constructs and with donor tissue procured from eye banks were assumed to be equivalent. One-way and probabilistic sensitivity analyses were performed to simulate various possible scenarios, and to determine the robustness of the results. A tissue engineering strategy was cheaper in both investment cost and recurring cost. Tissue-engineered constructs for endothelial keratoplasty could be produced at a cost of US$880 per transplant. In contrast, utilizing donor tissue procured from eye banks for endothelial keratoplasty required US$3,710 per transplant. Sensitivity analyses performed further support the results of this cost-minimization analysis across a wide range of possible scenarios. The use of tissue-engineered constructs for endothelial keratoplasty could potentially increase the supply of transplantable tissue and bring the costs of corneal endothelial transplantation down, making this intervention accessible to a larger group of patients. Tissue-engineering strategies for corneal epithelial constructs or other tissue types, such as pancreatic islet cells, should also be subject to similar pharmacoeconomic analyses. PMID:24949869

A cost-minimization analysis of tissue-engineered constructs for corneal endothelial transplantation.

PubMed

Tan, Tien-En; Peh, Gary S L; George, Benjamin L; Cajucom-Uy, Howard Y; Dong, Di; Finkelstein, Eric A; Mehta, Jodhbir S

2014-01-01

Corneal endothelial transplantation or endothelial keratoplasty has become the preferred choice of transplantation for patients with corneal blindness due to endothelial dysfunction. Currently, there is a worldwide shortage of transplantable tissue, and demand is expected to increase further with aging populations. Tissue-engineered alternatives are being developed, and are likely to be available soon. However, the cost of these constructs may impair their widespread use. A cost-minimization analysis comparing tissue-engineered constructs to donor tissue procured from eye banks for endothelial keratoplasty was performed. Both initial investment costs and recurring costs were considered in the analysis to arrive at a final tissue cost per transplant. The clinical outcomes of endothelial keratoplasty with tissue-engineered constructs and with donor tissue procured from eye banks were assumed to be equivalent. One-way and probabilistic sensitivity analyses were performed to simulate various possible scenarios, and to determine the robustness of the results. A tissue engineering strategy was cheaper in both investment cost and recurring cost. Tissue-engineered constructs for endothelial keratoplasty could be produced at a cost of US$880 per transplant. In contrast, utilizing donor tissue procured from eye banks for endothelial keratoplasty required US$3,710 per transplant. Sensitivity analyses performed further support the results of this cost-minimization analysis across a wide range of possible scenarios. The use of tissue-engineered constructs for endothelial keratoplasty could potentially increase the supply of transplantable tissue and bring the costs of corneal endothelial transplantation down, making this intervention accessible to a larger group of patients. Tissue-engineering strategies for corneal epithelial constructs or other tissue types, such as pancreatic islet cells, should also be subject to similar pharmacoeconomic analyses.

The involvement of endothelial mediators in leprosy.

PubMed

Nogueira, Maria Renata Sales; Latini, Ana Carla Pereira; Nogueira, Maria Esther Salles

2016-10-01

Leprosy is a chronic infectious disease that requires better understanding since it continues to be a significant health problem in many parts of the world. Leprosy reactions are acute inflammatory episodes regarded as the central etiology of nerve damage in the disease. The activation of endothelium is a relevant phenomenon to be investigated in leprosy reactions. The present study evaluated the expression of endothelial factors in skin lesions and serum samples of leprosy patients. Immunohistochemical analysis of skin samples and serum measurements of VCAM-1, VEGF, tissue factor and thrombomodulin were performed in 77 leprosy patients and 12 controls. We observed significant increase of VCAM-1 circulating levels in non-reactional leprosy (p = 0.0009). The immunostaining of VEGF and tissue factor was higher in endothelium of non-reactional leprosy (p = 0.02 for both) than healthy controls. Patients with type 1 reaction presented increased thrombomodulin serum levels, compared with non-reactional leprosy (p = 0.02). In type 2 reaction, no significant modifications were observed for the endothelial factors investigated. The anti-inflammatory and antimicrobial activities of the endotfhelial factors may play key-roles in the pathogenesis of leprosy and should be enrolled in studies focusing on alternative targets to improve the management of leprosy and its reactions.

Impairment of endothelial cell differentiation from bone marrow-derived mesenchymal stem cells: new insight into the pathogenesis of systemic sclerosis.

PubMed

Cipriani, P; Guiducci, S; Miniati, I; Cinelli, M; Urbani, S; Marrelli, A; Dolo, V; Pavan, A; Saccardi, R; Tyndall, A; Giacomelli, R; Cerinic, M Matucci

2007-06-01

Systemic sclerosis (SSc) is a disorder characterized by vascular damage and fibrosis of the skin and internal organs. Despite marked tissue hypoxia, there is no evidence of compensatory angiogenesis. The ability of mesenchymal stem cells (MSCs) to differentiate into endothelial cells was recently demonstrated. The aim of this study was to determine whether impaired differentiation of MSCs into endothelial cells in SSc might contribute to disease pathogenesis by decreasing endothelial repair. MSCs obtained from 7 SSc patients and 15 healthy controls were characterized. The number of colony-forming unit-fibroblastoid colonies was determined. After culture in endothelial-specific medium, the endothelial-like MSC (EL-MSC) phenotype was assessed according to the surface expression of vascular endothelial growth factor receptors (VEGFRs). Senescence, chemoinvasion, and capillary morphogenesis studies were also performed. MSCs from SSc patients displayed the same phenotype and clonogenic activity as those from controls. In SSc MSCs, a decreased percentage of VEGFR-2+, CXCR4+, VEGFR-2+/CXCR4+ cells and early senescence was detected. After culturing, SSc EL-MSCs showed increased expression of VEGFR-1, VEGFR-2, and CXCR4, did not express CD31 or annexin V, and showed significantly decreased migration after specific stimuli. Moreover, the addition of VEGF and stromal cell-derived factor 1 to cultured SSc EL-MSCs increased their angiogenic potential less than that in controls. Our data strongly suggest that endothelial repair may be affected in SSc. The possibility that endothelial progenitor cells could be used to increase vessel growth in chronic ischemic tissues may open up new avenues in the treatment of vascular damage caused by SSc.

[Effect of Leonurus Heterophyllus Sweet on tissue factor transcription and expression in human umbilical vein endothelial cells in vitro].

PubMed

Zheng, Lian; Fang, Chi-hua

2007-06-01

To investigate the effect of Leonurus Heterophyllus Sweet, (LHS) on tissue factor (TF) transcription and expression induced by thrombin in human umbilical vein endothelial cells (HUVECs). HUVECs were incubated with different concentrations of LHS and the TF mRNA expression was detected by reverse transcript-polymerase chain reaction (RT-PCR). LHS treatment of HUVECs at different concentrations and for different times resulted in significant differences in TF expression (Plt;0.01). The transcription of TF in LHS-treated cells was significantly different from that of the blank control group (Plt;0.01). LHS can decrease the expression of TF and intervene with TF transcription in HUVECs in vitro.

Collagen-binding VEGF mimetic peptide: Structure, matrix interaction, and endothelial cell activation

NASA Astrophysics Data System (ADS)

Chan, Tania R.

Long term survival of artificial tissue constructs depends greatly on proper vascularization. In nature, differentiation of endothelial cells and formation of vasculature are directed by dynamic spatio-temporal cues in the extracellular matrix that are difficult to reproduce in vitro. In this dissertation, we present a novel bifunctional peptide that mimics matrix-bound vascular endothelial growth factor (VEGF), which can be used to encode spatially controlled angiogenic signals in collagen-based scaffolds. The peptide, QKCMP, contains a collagen mimetic domain (CMP) that binds to type I collagen by a unique triple helix hybridization mechanism and a VEGF mimetic domain (QK) with pro-angiogenic activity. We demonstrate QKCMP's ability to hybridize with native and heat denatured collagens through a series of binding studies on collagen and gelatin substrates. Circular dichroism experiments show that the peptide retains the triple helical structure vital for collagen binding, and surface plasmon resonance study confirms the molecular interaction between the peptide and collagen strands. Cell culture studies demonstrate QKCMP's ability to induce endothelial cell morphogenesis and network formation as a matrix-bound factor in 2D and 3D collagen scaffolds. We also show that the peptide can be used to spatially modify collagen-based substrates to promote localized endothelial cell activation and network formation. To probe the biological events that govern these angiogenic cellular responses, we investigated the cell signaling pathways activated by collagen-bound QKCMP and determined short and long-term endothelial cell response profiles for p38, ERK1/2, and Akt signal transduction cascades. Finally, we present our efforts to translate the peptide's in vitro bioactivity to an in vivo burn injury animal model. When implanted at the wound site, QKCMP functionalized biodegradable hydrogels induce enhanced neovascularization in the granulation tissue. The results show QKCMP's efficacy as a matrix-bound angiogenic factor that directs endothelial cell proliferation and migration. These findings suggest that QKCMP can be used to enhance microvasculature formation during wound healing as well as to promote spatially controlled microvasculature for tissue engineering applications.

Factor X/Xa elicits protective signaling responses in endothelial cells directly via PAR-2 and indirectly via endothelial protein C receptor-dependent recruitment of PAR-1.

PubMed

Bae, Jong-Sup; Yang, Likui; Rezaie, Alireza R

2010-11-05

We recently demonstrated that the Gla domain-dependent interaction of protein C with endothelial protein C receptor (EPCR) leads to dissociation of the receptor from caveolin-1 and recruitment of PAR-1 to a protective signaling pathway. Thus, the activation of PAR-1 by either thrombin or PAR-1 agonist peptide elicited a barrier-protective response if endothelial cells were preincubated with protein C. In this study, we examined whether other vitamin K-dependent coagulation protease zymogens can modulate PAR-dependent signaling responses in endothelial cells. We discovered that the activation of both PAR-1 and PAR-2 in endothelial cells pretreated with factor FX (FX)-S195A, but not other procoagulant protease zymogens, also results in initiation of protective intracellular responses. Interestingly, similar to protein C, FX interaction with endothelial cells leads to dissociation of EPCR from caveolin-1 and recruitment of PAR-1 to a protective pathway. Further studies revealed that, FX activated by factor VIIa on tissue factor bearing endothelial cells also initiates protective signaling responses through the activation of PAR-2 independent of EPCR mobilization. All results could be recapitulated by the receptor agonist peptides to both PAR-1 and PAR-2. These results suggest that a cross-talk between EPCR and an unknown FX/FXa receptor, which does not require interaction with the Gla domain of FX, recruits PAR-1 to protective signaling pathways in endothelial cells.

A Bilayer Construct Controls Adipose-Derived Stem Cell Differentiation into Endothelial Cells and Pericytes without Growth Factor Stimulation

DTIC Science & Technology

2011-01-01

A Bilayer Construct Controls Adipose-Derived Stem Cell Differentiation into Endothelial Cells and Pericytes Without Growth Factor Stimulation...Ph.D.3 This work describes the differentiation of adipose-derived mesenchymal stem cells (ASC) in a composite hy- drogel for use as a vascularized...tissue from a single population of ASC. This work underscores the importance of the extracellular matrix in controlling stem cell phenotype. It is our

Neo-vascularization of the stroke cavity by implantation of human neural stem cells on VEGF-releasing PLGA microparticles

PubMed Central

Bible, Ellen; Qutachi, Omar; Chau, David Y.S.; Alexander, Morgan R.; Shakesheff, Kevin M.; Modo, Michel

2012-01-01

Replacing the tissue lost after a stroke potentially provides a new neural substrate to promote recovery. However, significant neurobiological and biotechnological challenges need to be overcome to make this possibility into a reality. Human neural stem cells (hNSCs) can differentiate into mature brain cells, but require a structural support that retains them within the cavity and affords the formation of a de novo tissue. Nevertheless, in our previous work, even after a week, this primitive tissue is void of a vasculature that could sustain its long-term viability. Therefore, tissue engineering strategies are required to develop a vasculature. Vascular endothelial growth factor (VEGF) is known to promote the proliferation and migration of endothelial cells during angio- and arteriogenesis. VEGF by itself here did not affect viability or differentiation of hNSCs, whereas growing cells on poly(D,L-lactic acid-co-glycolic acid) (PLGA) microparticles, with or without VEGF, doubled astrocytic and neuronal differentiation. Secretion of a burst and a sustained delivery of VEGF from the microparticles in vivo attracted endothelial cells from the host into this primate tissue and in parts established a neovasculature, whereas in other parts endothelial cells were merely interspersed with hNSCs. There was also evidence of a hypervascularization indicating that further work will be required to establish an adequate level of vascularization. It is therefore possible to develop a putative neovasculature within de novo tissue that is forming inside a tissue cavity caused by a stroke. PMID:22818980

* Central Growth Factor Loaded Depots in Bone Tissue Engineering Scaffolds for Enhanced Cell Attraction.

PubMed

Quade, Mandy; Knaack, Sven; Akkineni, Ashwini Rahul; Gabrielyan, Anastasia; Lode, Anja; Rösen-Wolff, Angela; Gelinsky, Michael

2017-08-01

Tissue engineering, the application of stem and progenitor cells in combination with an engineered extracellular matrix, is a promising strategy for bone regeneration. However, its success is limited by the lack of vascularization after implantation. The concept of in situ tissue engineering envisages the recruitment of cells necessary for tissue regeneration from the host environment foregoing ex vivo cell seeding of the scaffold. In this study, we developed a novel scaffold system for enhanced cell attraction, which is based on biomimetic mineralized collagen scaffolds equipped with a central biopolymer depot loaded with chemotactic agents. In humid milieu, as after implantation, the signaling factors are expected to slowly diffuse out of the central depot forming a gradient that stimulates directed cell migration toward the scaffold center. Heparin, hyaluronic acid, and alginate have been shown to be capable of depot formation. By using vascular endothelial growth factor (VEGF) as model factor, it was demonstrated that the release kinetics can be adjusted by varying the depot composition. While alginate and hyaluronic acid are able to reduce the initial burst and prolong the release of VEGF, the addition of heparin led to a much stronger retention that resulted in an almost linear release over 28 days. The biological activity of released VEGF was proven for all variants using an endothelial cell proliferation assay. Furthermore, migration experiments with endothelial cells revealed a relationship between the degree of VEGF retention and migration distance: cells invaded deepest in scaffolds containing a heparin-based depot indicating that the formation of a steep gradient is crucial for cell attraction. In conclusion, this novel in situ tissue engineering approach, specifically designed to recruit and accommodate endogenous cells upon implantation, appeared highly promising to stimulate cell invasion, which in turn would promote vascularization and finally new bone formation.

Laser-guided direct writing for three-dimensional tissue engineering: Analysis and application of radiation forces

NASA Astrophysics Data System (ADS)

Nahmias, Yaakov Koby

Tissue Engineering aims for the creation of functional tissues or organs using a combination of biomaterials and living cells. Artificial tissues can be implanted in patients to restore tissue function that was lost due to trauma, disease, or genetic disorder. Tissue equivalents may also be used to screen the effects of drugs and toxins, reducing the use of animals in research. One of the principle limitations to the size of engineered tissue is oxygen and nutrient transport. Lacking their own vascular bed, cells embedded in the engineered tissue will consume all available oxygen within hours while out branching blood vessels will take days to vascularize the implanted tissue. Establishing capillaries within the tissue prior to implantation can potentially eliminate this limitation. One approach to establishing capillaries within the tissue is to directly write endothelial cells with micrometer accuracy as it is being built. The patterned endothelial cells will then self-assemble into vascular structures within the engineering tissue. The cell patterning technique known as laser-guided direct writing can confine multiple cells in a laser beam and deposit them as a steady stream on any non-absorbing surface with micrometer scale accuracy. By applying the generalized Lorenz-Mie theory for light scattering on laser-guided direct writing we were able to accurately predict the behavior of with various cells and particles in the focused laser. In addition, two dimensionless parameters were identified for general radiation-force based system design. Using laser-guided direct writing we were able to direct the assembly of endothelial vascular structures with micrometer accuracy in two and three dimensions. The patterned vascular structures provided the backbone for subsequent in vitro liver morphogenesis. Our studies show that hepatocytes migrate toward and adhere to endothelial vascular structures in response to endothelial-secreted hepatocyte growth factor (HGF). Our approach has the advantage of retaining the natural heterotypic cell-cell interaction and spatial arrangement of native tissue, which is important for proper tissue function.* *This dissertation is a compound document (contains both a paper copy and a CD as part of the dissertation). The CD requires the following system requirements: Microsoft Office; Windows MediaPlayer or RealPlayer.

Expression of Vascular Notch Ligand Delta-Like 4 and Inflammatory Markers in Breast Cancer

PubMed Central

Jubb, Adrian M.; Soilleux, Elizabeth J.; Turley, Helen; Steers, Graham; Parker, Andrew; Low, Irene; Blades, Jennifer; Li, Ji-Liang; Allen, Paul; Leek, Russell; Noguera-Troise, Irene; Gatter, Kevin C.; Thurston, Gavin; Harris, Adrian L.

2010-01-01

Delta-like ligand 4 (Dll4) is a Notch ligand that is predominantly expressed in the endothelium. Evidence from xenografts suggests that inhibiting Dll4 may overcome resistance to antivascular endothelial growth factor therapy. The aims of this study were to characterize the expression of Dll4 in breast cancer and assess whether it is associated with inflammatory markers and prognosis. We examined 296 breast adenocarcinomas and 38 ductal carcinoma in situ tissues that were represented in tissue microarrays. Additional whole sections representing 10 breast adenocarcinomas, 10 normal breast tissues, and 16 angiosarcomas were included. Immunohistochemistry was then performed by using validated antibodies against Dll4, CD68, CD14, Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin (DC-SIGN), CD123, neutrophil elastase, CD31, and carbonic anhydrase 9. Dll4 was selectively expressed by intratumoral endothelial cells in 73% to 100% of breast adenocarcinomas, 18% of in situ ductal carcinomas, and all lactating breast cases, but not normal nonlactating breast. High intensity of endothelial Dll4 expression was a statistically significant adverse prognostic factor in univariate (P = 0.002 and P = 0.01) and multivariate analyses (P = 0.03 and P = 0.04) of overall survival and relapse-free survival, respectively. Among the inflammatory markers, only CD68 and DC-SIGN were significant prognostic factors in univariate (but not multivariate) analyses of overall survival (P = 0.01 and 0.002, respectively). In summary, Dll4 was expressed by endothelium associated with breast cancer cells. In these retrospective subset analyses, endothelial Dll4 expression was a statistically significant multivariate prognostic factor. PMID:20167860

Expression and localization of endocrine gland-derived vascular endothelial growth factor (EG-VEGF) in human pancreas and pancreatic adenocarcinoma.

PubMed

Morales, Angélica; Vilchis, Felipe; Chávez, Bertha; Chan, Carlos; Robles-Díaz, Guillermo; Díaz-Sánchez, Vicente

2007-10-01

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) was recently identified as the first tissue-specific angiogenic molecule. EG-VEGF (the gene product of PROK-1) appears to be expressed exclusively in steroid-producing organs such as the ovary, testis, adrenals and placenta. Since the human pancreatic cells retain steroidogenic activity, in the present study we ascertained whether this angiogenic factor is expressed in normal pancreas and pancreatic adenocarcinoma. Tissue samples from normal males (n=5), normal females (n=5) and from surgically resected adenocarcinomas (n=2) were processed for RT-PCR and immunohistochemical studies. Results from semi-quantitative analysis by RT-PCR suggest a distinct expression level for EG-VEGF in the different tissue samples. The relative amount of EG-VEGF mRNA in pancreas was more abundant in female adenocarcinoma (0.89) followed by male adenocarcinoma (0.71), than normal female (0.64) and normal male (0.38). The expression of mRNA for EG-VEGF in normal tissue was significantly higher in females than in males. All samples examined showed specific immunostaining for EG-VEGF. In male preparations, the positive labeling was localized predominantly within the pancreatic islets while in female preparations the main staining was detected towards the exocrine portion. Specific immunolabeling was also observed in endothelial cells of pancreatic blood vessels. Our data provide evidence that the human pancreas expresses the EG-VEGF, a highly specific mitogen which regulates proliferation and differentiation of the vascular endothelium. The significance of this finding could be interpreted as either, EG-VEGF is not exclusive of endocrine organs, or the pancreas should be considered as a functional steroidogenic tissue. The extent of the expression of EG-VEGF appears to have a dimorphic pattern in normal and tumoral pancreatic tissue.

Air pollution upregulates endothelial cell procoagulant activity via ultrafine particle-induced oxidant signaling and tissue factor expression.

PubMed

Snow, S J; Cheng, W; Wolberg, A S; Carraway, M S

2014-07-01

Air pollution exposure is associated with cardiovascular events triggered by clot formation. Endothelial activation and initiation of coagulation are pathophysiological mechanisms that could link inhaled air pollutants to vascular events. Here we investigated the underlying mechanisms of increased endothelial cell procoagulant activity following exposure to soluble components of ultrafine particles (soluble UF). Human coronary artery endothelial cells (HCAEC) were exposed to soluble UF and assessed for their ability to trigger procoagulant activity in platelet-free plasma. Exposed HCAEC triggered earlier thrombin generation and faster fibrin clot formation, which was abolished by an anti-tissue factor (TF) antibody, indicating TF-dependent effects. Soluble UF exposure increased TF mRNA expression without compensatory increases in key anticoagulant proteins. To identify early events that regulate TF expression, we measured endothelial H2O2 production following soluble UF exposure and identified the enzymatic source. Soluble UF exposure increased endothelial H2O2 production, and antioxidants attenuated UF-induced upregulation of TF, linking the procoagulant responses to reactive oxygen species (ROS) formation. Chemical inhibitors and RNA silencing showed that NOX-4, an important endothelial source of H2O2, was involved in UF-induced upregulation of TF mRNA. These data indicate that soluble UF exposure induces endothelial cell procoagulant activity, which involves de novo TF synthesis, ROS production, and the NOX-4 enzyme. These findings provide mechanistic insight into the adverse cardiovascular effects associated with air pollution exposure. Published by Oxford University Press on behalf of Toxicological Sciences 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Neuropilin-2 promotes extravasation and metastasis by interacting with endothelial α5 integrin.

PubMed

Cao, Ying; Hoeppner, Luke H; Bach, Steven; E, Guangqi; Guo, Yan; Wang, Enfeng; Wu, Jianmin; Cowley, Mark J; Chang, David K; Waddell, Nicola; Grimmond, Sean M; Biankin, Andrew V; Daly, Roger J; Zhang, Xiaohui; Mukhopadhyay, Debabrata

2013-07-15

Metastasis, the leading cause of cancer death, requires tumor cell intravasation, migration through the bloodstream, arrest within capillaries, and extravasation to invade distant tissues. Few mechanistic details have been reported thus far regarding the extravasation process or re-entry of circulating tumor cells at metastatic sites. Here, we show that neuropilin-2 (NRP-2), a multifunctional nonkinase receptor for semaphorins, vascular endothelial growth factor (VEGF), and other growth factors, expressed on cancer cells interacts with α5 integrin on endothelial cells to mediate vascular extravasation and metastasis in zebrafish and murine xenograft models of clear cell renal cell carcinoma (RCC) and pancreatic adenocarcinoma. In tissue from patients with RCC, NRP-2 expression is positively correlated with tumor grade and is highest in metastatic tumors. In a prospectively acquired cohort of patients with pancreatic cancer, high NRP-2 expression cosegregated with poor prognosis. Through biochemical approaches as well as Atomic Force Microscopy (AFM), we describe a unique mechanism through which NRP-2 expressed on cancer cells interacts with α5 integrin on endothelial cells to mediate vascular adhesion and extravasation. Taken together, our studies reveal a clinically significant role of NRP-2 in cancer cell extravasation and promotion of metastasis. ©2013 AACR.

Serum vascular endothelial growth factor in dogs with soft tissue sarcomas.

PubMed

de Queiroz, G Fernandes; Dagli, M Lúcia Zaidan; Meira, S Aparecida; Matera, J Maria

2013-09-01

This work aimed to evaluate serum vascular endothelial growth factor (VEGF) in 25 dogs with soft tissue sarcoma, and in 30 healthy dogs. Blood was collected once time from the control animals and three times, in the same way, from animals with sarcoma. Blood count was performed in the blood collected, and serum VEGF was measured by enzyme-linked immunosorbent assay quantitative method. Serum VEGF in control animals was similar to patients with soft tissue sarcoma. There was a reduction in serum VEGF after the sarcoma resection. There was positive correlation between serum VEGF and neutrophil counts, and negative between VEGF and hemoglobin content in animals with sarcoma. Animals with hemangiopericytoma showed higher serum VEGF levels compared to the patients with malignant peripheral nerve sheath. Circulating blood cells can contribute to elevate VEGF serum concentrations in dogs with soft tissue sarcomas and a possible role of VEGF in the angiogenesis of these tumors. © 2012 John Wiley & Sons Ltd.

Detecting Tie2, an endothelial growth factor receptor, by using immunohistochemistry in mouse lungs.

PubMed

Guha, Prajna P; David, Sascha A; Ghosh, Chandra C

2014-01-01

Immunohistochemical (IHC) staining is an invaluable, sensitive, and effective method to detect the presence and localization of proteins in the cellular compartment in tissues. The basic concept of IHC is detecting the antigen in tissues by means of specific antibody binding, which is then demonstrated with a colored histochemical reaction that can be observed under a light microscope. The most challenging aspect of IHC techniques is optimizing the precise experimental conditions that are required to get a specific and a strong signal. The critical steps of IHC are specimen acquisition, fixation, permeabilization, detection system, and selection of the antigen specific antibody and its optimization. Here, we elaborate the technique using the endothelial growth factor binding receptor Tie2 in mouse lungs.

Preparation and features of polycaprolactone vascular grafts with the incorporated vascular endothelial growth factor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sevostyanova, V. V., E-mail: sevostyanova.victoria@gmail.com; Khodyrevskaya, Y. I.; Glushkova, T. V.

The development of tissue-engineered small-diameter vascular grafts is an urgent issue in cardiovascular surgery. In this study, we assessed how the incorporation of the vascular endothelial growth factor (VEGF) affects morphological and mechanical properties of polycaprolactone (PCL) vascular grafts along with its release kinetics. Vascular grafts were prepared using two-phase electrospinning. In pursuing our aims, we performed scanning electron microscopy, mechanical testing, and enzyme-linked immunosorbent assay. Our results demonstrated the preservation of a highly porous structure and improvement of PCL/VEGF scaffold mechanical properties as compared to PCL grafts. A prolonged VEGF release testifies the use of this construct as amore » scaffold for tissue-engineered vascular grafts.« less

Endothelial connexin 32 regulates tissue factor expression induced by inflammatory stimulation and direct cell-cell interaction with activated cells.

PubMed

Okamoto, Takayuki; Akita, Nobuyuki; Hayashi, Tatsuya; Shimaoka, Motomu; Suzuki, Koji

2014-10-01

Endothelial cell (EC) interacts with adjacent EC through gap junction, and abnormal expression or function of Cxs is associated with cardiovascular diseases. In patients with endothelial dysfunction, the up-regulation of tissue factor (TF) expression promotes the pathogenic activation of blood coagulation, however the relationship between gap junctions and TF expression in ECs remains uncharacterized. ECs express the gap junction (GJ) proteins connexin32 (Cx32), Cx37, Cx40 and Cx43. We investigated the role of endothelial gap junctions, particularly Cx32, in modulating TF expression during vascular inflammation. Human umbilical vein endothelial cells (HUVECs) were stimulated with tumor necrosis factor-α (TNF-α) and TF activity was assessed in the presence of GJ blockers and an inhibitory anti-Cx32 monoclonal antibody. Treatment with GJ blockers and anti-Cx32 monoclonal antibody enhanced the TNF-α-induced TF activity and mRNA expression in HUVECs. TNF-α-activated effector HUVECs or mouse MS-1 cells were co-cultured with non-stimulated acceptor HUVECs and TF expression in acceptor HUVECs was detected. Effector EC induced TF expression in adjacent acceptor HUVECs through direct cell-cell interaction. Cell-cell interaction induced TF expression was reduced by anti-intercellular adhesion molecule-1 (ICAM1) monoclonal antibody. Soluble ICAM1-Fc fusion protein promotes TF expression. GJ blockers and anti-Cx32 monoclonal antibody enhanced TF expression induced by cell-cell interaction and ICAM1-Fc treatment. Blockade of endothelial Cx32 increased TF expression induced by TNF-α stimulation and cell-cell interaction which was at least partly dependent upon ICAM1. These results suggest that direct Cx32-mediated interaction modulates TF expression in ECs during vascular inflammation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

The secretome of endothelial progenitor cells promotes brain endothelial cell activity through PI3-kinase and MAP-kinase.

PubMed

Di Santo, Stefano; Seiler, Stefanie; Fuchs, Anna-Lena; Staudigl, Jennifer; Widmer, Hans Rudolf

2014-01-01

Angiogenesis and vascular remodelling are crucial events in tissue repair mechanisms promoted by cell transplantation. Current evidence underscores the importance of the soluble factors secreted by stem cells in tissue regeneration. In the present study we investigated the effects of paracrine factors derived from cultured endothelial progenitor cells (EPC) on rat brain endothelial cell properties and addressed the signaling pathways involved. Endothelial cells derived from rat brain (rBCEC4) were incubated with EPC-derived conditioned medium (EPC-CM). The angiogenic response of rBCEC4 to EPC-CM was assessed as effect on cell number, migration and tubular network formation. In addition, we have compared the outcome of the in vitro experiments with the effects on capillary sprouting from rat aortic rings. The specific PI3K/AKT inhibitor LY294002 and the MEK/ERK inhibitor PD98059 were used to study the involvement of these two signaling pathways in the transduction of the angiogenic effects of EPC-CM. Viable cell number, migration and tubule network formation were significantly augmented upon incubation with EPC-CM. Similar findings were observed for aortic ring outgrowth with significantly longer sprouts. The EPC-CM-induced activities were significantly reduced by the blockage of the PI3K/AKT and MEK/ERK signaling pathways. Similarly to the outcome of the rBCEC4 experiments, inhibition of the PI3K/AKT and MEK/ERK pathways significantly interfered with capillary sprouting induced by EPC-CM. The present study demonstrates that EPC-derived paracrine factors substantially promote the angiogenic response of brain microvascular endothelial cells. In addition, our findings identified the PI3K/AKT and MEK/ERK pathways to play a central role in mediating these effects.

Hypoxia-driven angiogenesis: role of tip cells and extracellular matrix scaffolding.

PubMed

Germain, Stéphane; Monnot, Catherine; Muller, Laurent; Eichmann, Anne

2010-05-01

Angiogenesis is a highly coordinated tissue remodeling process leading to blood vessel formation. Hypoxia triggers angiogenesis via induction of expression of growth factors such as vascular endothelial growth factor (VEGF). VEGF instructs endothelial cells to form tip cells, which lead outgrowing capillary sprouts, whereas Notch signaling inhibits sprout formation. Basement membrane deposition and mechanical cues from the extracellular matrix (ECM) induced by hypoxia may participate to coordinated vessel sprouting in conjunction with the VEGF and Notch signaling pathways. Hypoxia regulates ECM composition, deposition, posttranslational modifications and rearrangement. In particular, hypoxia-driven vascular remodeling is dynamically regulated through modulation of ECM-modifying enzyme activities that eventually affect both matricellular proteins and growth factor availability. Better understanding of the complex interplay between endothelial cells and soluble growth factors and mechanical factors from the ECM will certainly have significant implications for understanding the regulation of developmental and pathological angiogenesis driven by hypoxia.

Ceramide-1-phosphate regulates migration of multipotent stromal cells (MSCs) and endothelial progenitor cells (EPCs) – implications for tissue regeneration

PubMed Central

Kim, ChiHwa; Schneider, Gabriela; Abdel-Latif, Ahmed; Mierzejewska, Kasia; Sunkara, Manjula; Borkowska, Sylwia; Ratajczak, Janina; Morris, Andrew J.; Kucia, Magda; Ratajczak, Mariusz Z.

2012-01-01

Ceramide-1-phosphate (C1P) is a bioactive lipid that, in contrast to ceramide, is an anti-apoptotic molecule released from cells that are damaged and “leaky”. As reported recently, C1P promotes migration of hematopoietic cells. In the current paper, we tested the hypothesis that C1P released upon tissue damage may play an underappreciated role in chemoattraction of various types of stem cells and endothelial cells involved in tissue/organ regeneration. We show for a first time that C1P is upregulated in damaged tissues and chemoattracts BM-derived multipotent stroma cells (MSCs), endothelial progenitor cells (EPCs), and very small embryonic-like stem cells (VSELs). Furthermore, compared to other bioactive lipids, C1P more potently chemoattracted human umbilical vein endothelial cells (HUVECs) and stimulated tube formation by these cells. C1P also promoted in vivo vascularization of Matrigel implants and stimulated secretion of stromal derived factor-1 (SDF-1) from BM-derived fibroblasts. Thus, our data demonstrate, for the first time, that C1P is a potent bioactive lipid released from damaged cells that potentially plays an important and novel role in recruitment of stem/progenitor cells to damaged organs and may promote their vascularization. PMID:23193025

Tissue factor is an angiogenic-specific receptor for factor VII-targeted immunotherapy and photodynamic therapy.

PubMed

Hu, Zhiwei; Cheng, Jijun; Xu, Jie; Ruf, Wolfram; Lockwood, Charles J

2017-02-01

Identification of target molecules specific for angiogenic vascular endothelial cells (VEC), the inner layer of pathological neovasculature, is critical for discovery and development of neovascular-targeting therapy for angiogenesis-dependent human diseases, notably cancer, macular degeneration and endometriosis, in which vascular endothelial growth factor (VEGF) plays a central pathophysiological role. Using VEGF-stimulated vascular endothelial cells (VECs) isolated from microvessels, venous and arterial blood vessels as in vitro angiogenic models and unstimulated VECs as a quiescent VEC model, we examined the expression of tissue factor (TF), a membrane-bound receptor on the angiogenic VEC models compared with quiescent VEC controls. We found that TF is specifically expressed on angiogenic VECs in a time-dependent manner in microvessels, venous and arterial vessels. TF-targeted therapeutic agents, including factor VII (fVII)-IgG1 Fc and fVII-conjugated photosensitizer, can selectively bind angiogenic VECs, but not the quiescent VECs. Moreover, fVII-targeted photodynamic therapy can selectively and completely eradicate angiogenic VECs. We conclude that TF is an angiogenic-specific receptor and the target molecule for fVII-targeted therapeutics. This study supports clinical trials of TF-targeted therapeutics for the treatment of angiogenesis-dependent diseases such as cancer, macular degeneration and endometriosis.

Elevated circulating soluble thrombomodulin activity, tissue factor activity and circulating procoagulant phospholipids: new and useful markers for pre-eclampsia?

PubMed

Rousseau, Aurélie; Favier, Rémi; Van Dreden, Patrick

2009-09-01

One of the most frequently proposed mechanisms for pre-eclampsia refers to uteroplacental thrombosis. However, the contribution of classical thrombotic risk factors remains questionable. The aims of this study were to investigate the activities of thrombomodulin, tissue factor and procoagulant phospholipids to assess endothelial cell injury in pregnant women with pre-eclampsia and to compare them with other classical markers of vascular injury and thrombotic risk. Using three new functional assays we studied the plasma levels of these new markers in 35 healthy women, 30 healthy pregnant women, and 35 women with pre-eclampsia. We found that plasma levels of thrombomodulin activity, tissue factor activity and procoagulant phospholipids were significantly elevated in women with pre-eclampsia versus normal pregnant and non-pregnant women. It is thus suggested that elevated levels of these parameters in pre-eclampsia may reflect vascular endothelium damage, and may be a more valuable biomarker than antigen for the assessment of endothelial damage in pre-eclampsia. The high increased levels of procoagulant phospholipids and tissue factor activities in pre-eclampsia could suggest that the procoagulant potential may be implicated in this complication and makes these markers very promising for the understanding, follow-up and therapeutic handling of complicated pregnancy.

[Expression of vascular endothelial growth factor and its significance in pulmonary bronchoalveolar carcinoma].

PubMed

Song, Weian; Li, Hui; Wang, Huasheng; Zhang, Weidong; Zhao, Xiaogang

2004-02-20

To study the relationship between the vascular endothelial growth factor (VEGF) and the clinicopathological characteristics of the patients with pulmonary bronchoalveolar carcinoma, and to research the possible role of VEGF in the malignant growth of pulmonary bronchoalveolar carcinoma. The expression of VEGF and MVD were detected in 38 pulmonary bronchoalveolar carcinoma and 20 normal lung tissues by immunohistochemical method. The positive rate of VEGF expression (73.68%,28/38) and MVD (63.81±19.26) in pulmonary bronchoalveolar carcinoma tissues were both remarkably higher than those in normal lung tissues (0, 18.44±6.53)( P < 0.005,P < 0.001). The positive rate of VEGF expression was significantly related to the size of tumor ( P < 0.05), lymphatic metastasis ( P < 0.025) and TNM stage ( P < 0.05), and so did the MVD ( P < 0.05, P < 0.05, P < 0.05). MVD was remarkably higher in VEGF (+) carcinoma tissues than that in VEGF (-) carcinoma tissues ( P < 0.05). VEGF correlates with the clinicopathological characteristics of pulmonary bronchoalveolar carcinoma. It may play an important role in the development of pulmonary bronchoalveolar carcinoma.

Effect of Flow on Gene Regulation in Smooth Muscle Cells and Macromolecular Transport Across Endothelial Cell Monolayers

NASA Technical Reports Server (NTRS)

McIntire, Larry V.; Wagner, John E.; Papadaki, Maria; Whitson, Peggy A.; Eskin, Suzanne G.

1996-01-01

Endothelial cells line all of the vessels of the circulatory system, providing a non-thrombogenic conduit for blood flow; they regulate many complex functions in the vasculature, such as coagulation, fibrinolysis, platelet aggregation, vessel tone and growth, and leukocyte traffic; and they form the principal barrier to transport of substances between the blood and the surrounding tissue space. The permeability of endothelial cell changes with environmental stimuli; shear stress, in particular, applied either in vivo, or in vitro, induces changes in protein expression and secretion of vasoactive factors by endothelial cells. The ability to study the effects of shear on the macromolecular permeability of the cerebral vasculature is particularly important, since in no other place is the barrier function of the endothelium more important than in the brain. The endothelial cells of this organ have developed special barrier properties that keep the cerebral system from experiencing any drastic change in composition; together with glial cells, they form the blood brain barrier (BBB). We have studied the effect of flow on bovine BBB using flow chambers and tissue culture systems.

LYVE1 and PROX1 in the reconstruction of hepatic sinusoids after partial hepatectomy in mice.

PubMed

Meng, F

2017-01-01

Revascularisation is crucial to liver regeneration after liver injury, but the process remains unclear. This study investigated changes in the levels and distribution of lymphatic vessel endothelial hyaluronan receptor 1 (LYVE1) and prospero homeobox protein 1 (PROX1) in liver tissue sections after partial hepatectomy in mice. Mice were subjected to partial hepatectomy. Control animals were sham-operated. From days 1 through 8, the remaining liver tissues were collected from 8 animals each day. Histology showed that after partial hepatectomy, the remaining liver tissue samples underwent initial degeneration and then hepatocyte proliferation and regeneration. Using immunohistochemical analysis, relative to the control a significantly higher number of vascular endothelial growth factor A (VEGFA)-positive hepatocytes was observed on days 4 and 5 after partial hepatectomy. LYVE1 was mainly present in the liver sinusoidal endothelial cells and the number of LYVE1-positive cells gradually increased with time. PROX1 was detected in some of the hepatocytes, but liver sinusoidal endothelial cells, artery, and vein were negative for PROX1 staining in the early stage after liver injury. The presence of PROX1 could be observed in some central veins as well as liver sinusoidal endothelial cells. Seven days after partial hepatectomy, colocalisation of PROX1 and LYVE1 was observed in liver sinusoidal endothelial cells and veins. This study revealed the dynamic process of revascularisation and hepatic sinusoid reconstruction during liver regeneration in response to liver injury in mice. PROX1 and LYVE1 may participate in this process and serve as biomarkers for identification of newly formed liver sinusoidal endothelial cells.

Endothelial sirtuin 1 inactivation enhances capillary rarefaction and fibrosis following kidney injury through Notch activation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kida, Yujiro; Zullo, Joseph A.; Renal Research Institute, Department of Physiology, New York Medical College, Valhalla, NY

Peritubular capillary (PTC) rarefaction along with tissue fibrosis is a hallmark of chronic kidney disease (CKD). However, molecular mechanisms of PTC loss have been poorly understood. Previous studies have demonstrated that functional loss of endothelial sirtuin 1 (SIRT1) impairs angiogenesis during development and tissue damage. Here, we found that endothelial SIRT1 dysfunction causes activation of endothelial Notch1 signaling, which leads to PTC rarefaction and fibrosis following kidney injury. In mice lacking functional SIRT1 in the endothelium (Sirt1 mutant), kidney injury enhanced apoptosis and senescence of PTC endothelial cells with impaired endothelial proliferation and expanded myofibroblast population and collagen deposition. Comparedmore » to wild-type kidneys, Sirt1 mutant kidneys up-regulated expression of Delta-like 4 (DLL4, a potent Notch1 ligand), Hey1 and Hes1 (Notch target genes), and Notch intracellular domain-1 (NICD1, active form of Notch1) in microvascular endothelial cells (MVECs) post-injury. Sirt1 mutant primary kidney MVECs reduced motility and vascular assembly and enhanced senescence compared to wild-type kidney MVECs. This difference in the phenotype was negated with Notch inhibition. Concurrent stimulation of DLL4 and transforming growth factor (TGF)-β1 increased trans-differentiation of primary kidney pericytes into myofibroblast more than TGF-β1 treatment alone. Collectively, these results indicate that endothelial SIRT1 counteracts PTC rarefaction by repression of Notch1 signaling and antagonizes fibrosis via suppression of endothelial DLL4 expression. - Highlights: • SIRT1 represses Notch1 signaling in capillary endothelial cells in the kidney. • Endothelial SIRT1 is depleted in the kidney following injury. • Activation of endothelial Notch impairs angiogenesis in the kidney. • Increased expression of endothelial DLL4 enhances renal fibrosis.« less

Nerve growth factor injected into the gastric ulcer base incorporates into endothelial, neuronal, glial and epithelial cells: implications for angiogenesis, mucosal regeneration and ulcer healing.

PubMed

Tanigawa, T; Ahluwalia, A; Watanabe, T; Arakawa, T; Tarnawski, A S

2015-08-01

A previous study has demonstrated that locally administered growth factors such as epidermal growth factor, basic fibroblast growth factor and hepatocyte growth factor can accelerate healing of experimental gastric ulcers in rats. That study indicates that locally administered growth factors can exert potent biological effects resulting in enhanced gastric ulcers healing. However, the fate of injected growth factors, their retention and localization to specific cellular compartments have not been examined. In our preliminary study, we demonstrated that local injection of nerve growth factor to the base of experimental gastric ulcers dramatically accelerates ulcer healing, increases angiogenesis - new blood vessel formation, and improves the quality of vascular and epithelial regeneration. Before embarking on larger, definitive and time sequence studies, we wished to determine whether locally injected nerve growth factor is retained in gastric ulcer's tissues and taken up by specific cells during gastric ulcer healing. Gastric ulcers were induced in anesthetized rats by local application of acetic acid using standard methods; and, 60 min later fluorescein isothiocyanate-labeled nerve growth factor was injected locally to the ulcer base. Rats were euthanized 2, 5 and 10 days later. Gastric specimens were obtained and processed for histology. Unstained paraffin sections were examined under a fluorescence microscope, and the incorporation of fluorescein isothiocyanate-labeled nerve growth factor into various gastric tissue cells was determined and quantified. In addition, we performed immunostaining for S100β protein that is expressed in neural components. Five and ten days after ulcer induction labeled nerve growth factor (injected to the gastric ulcer base) was incorporated into endothelial cells of blood vessels, neuronal, glial and epithelial cells, myofibroblasts and muscle cells. This study demonstrates for the first time that during gastric ulcer healing locally administered exogenous nerve growth factor is retained in gastric tissue and is taken up by endothelial, neural, muscle and epithelial cells. This is likely the basis for the therapeutic action of locally administered nerve growth factor and its stimulation of angiogenesis, tissue regeneration and gastric ulcer healing.

Induction of vascular endothelial phenotype and cellular proliferation from human cord blood stem cells cultured in simulated microgravity

NASA Astrophysics Data System (ADS)

Chiu, Brian; Z-M Wan, Jim; Abley, Doris; Akabutu, John

2005-05-01

Recent studies have demonstrated that stem cells derived from adult hematopoietic tissues are capable of trans-differentiation into non-hematopoietic cells, and that the culture in microgravity ( μg) may modulate the proliferation and differentiation. We investigated the application of μg to human umbilical cord blood stem cells (CBSC) in the induction of vascular endothelial phenotype expression and cellular proliferation. CD34+ mononuclear cells were isolated from waste human umbilical cord blood samples and cultured in simulated μg for 14 days. The cells were seeded in rotary wall vessels (RWV) with or without microcarrier beads (MCB) and vascular endothelial growth factor was added during culture. Controls consisted of culture in 1 G. The cell cultures in RWV were examined by inverted microscopy. Cell counts, endothelial cell and leukocyte markers performed by flow-cytometry and FACS scan were assayed at days 1, 4, 7 and at the termination of the experiments. Culture in RWV revealed significantly increased cellular proliferation with three-dimensional (3D) tissue-like aggregates. At day 4, CD34+ cells cultured in RWV bioreactor without MCB developed vascular tubular assemblies and exhibited endothelial phenotypic markers. These data suggest that CD34+ human umbilical cord blood progenitors are capable of trans-differentiation into vascular endothelial cell phenotype and assemble into 3D tissue structures. Culture of CBSC in simulated μg may be potentially beneficial in the fields of stem cell biology and somatic cell therapy.

Effects of radiotherapy and chemotherapy on angiogenesis and leukocyte infiltration in rectal cancer.

PubMed

Baeten, Coen I M; Castermans, Karolien; Lammering, Guido; Hillen, Femke; Wouters, Bradly G; Hillen, Harry F P; Griffioen, Arjan W; Baeten, Cornelius G M I

2006-11-15

We and others have shown that angiogenesis and leukocyte infiltration are important prognostic factors in rectal cancer. However, little is known about its possible changes in response to radiotherapy (RTX), which is frequently given to rectal tumors as a neoadjuvant treatment to improve the prognosis. We therefore investigated the biologic effects of RTX on these parameters using fresh-frozen biopsy samples of tumor and normal mucosa tissue before and after RTX. Biopsy samples were taken from a total of 34 patients before and after either a short course or long course of RTX combined with chemotherapy. The following parameters were analyzed by immunohistochemistry, flow cytometry, or quantitative real-time polymerase chain reaction: Microvessel density, leukocyte infiltration, proliferating epithelial and tumor cells, proliferating endothelial cells, adhesion molecule expression on endothelial cells, and the angiogenic mRNA profile. The tumor biopsy samples taken after RTX treatment demonstrated a significant decrease in microvessel density and the number of proliferating tumor cells and proliferating endothelial cells (p < 0.001). In contrast, the leukocyte infiltration, the levels of basic fibroblast growth factor in carcinoma tissue, and the adhesion molecule expression on endothelial cells in normal as well as carcinoma tissue increased significantly (p < 0.05). Our data show that together with an overall decrease in tumor cell and endothelial cell proliferation, RTX results in an increase in the expression of adhesion molecules that stimulate leukocyte infiltration. This suggests the possibility that, in addition to its direct cytotoxic effect, radiation may also stimulate an immunologic tumor response that could contribute to the documented improvement in local tumor control and distal failure rate of rectal cancers.

Antiangiogenic activity of vitexicarpine in experimentally induced hepatocellular carcinoma: Impact on vascular endothelial growth factor pathway.

PubMed

Hassoun, Shimaa M; Abdel-Rahman, Noha; Eladl, Entsar I; El-Shishtawy, Mamdouh M

2017-06-01

Angiogenesis plays important roles in progression of hepatocellular carcinoma. The antiangiogenic mechanisms of vitexicarpine are not fully defined. Therefore, we conducted the following study to evaluate the antiangiogenic mechanism and antitumor activity of vitexicarpine in vivo model of hepatocellular carcinoma through modulation of vascular endothelial growth factor signaling pathway. Hepatocellular carcinoma was induced in Sprague Dawley rats by thioacetamide. Hepatocellular carcinoma was assessed by measuring serum alpha-fetoprotein and investigating liver sections stained with hematoxylin/eosin. Hepatocellular carcinoma rats were injected with vitexicarpine (150 mg/kg) for 2 weeks. Hepatic vascular endothelial growth factor was measured by enzyme-linked immunosorbent assay. Protein and expression of hepatic phospho-Ser473-AKT (p-AKT) and phospho-Tyr419-Src (p-Src) were determined. The apoptotic pathway was evaluated by assessment of protein expression of caspase-3. Vitexicarpine increased rats' survival time and decreased serum alpha-fetoprotein as well as it ameliorated fibrosis and massive hepatic tissue breakdown. It attenuated hepatocellular carcinoma-induced protein and gene expression of vascular endothelial growth factor, p-AKT, p-Src, and caspase-3. In conclusion, this study suggests that vitexicarpine possesses both antiangiogenic and antitumor activities through inhibition of vascular endothelial growth factor, p-AKT/AKT, and p-Src with subsequent inhibition of apoptotic pathway.

Regulation by basic fibroblast growth factor of glycosaminoglycan biosynthesis in cultured vascular endothelial cells.

PubMed

Kaji, T; Hiraga, S; Ohkawara, S; Inada, M; Yamamoto, C; Kozuka, H; Koizumi, F

1995-05-01

The alteration of glycosaminoglycans (GAGs) in cultured bovine aortic endothelial cells after exposure to basic fibroblast growth factor (bFGF) was investigated. It was found that the incorporation of [3H]glucosamine into GAGs was markedly increased by bFGF in both the cell layer and the conditioned medium; however, that of [35S]sulfate was not changed by the growth factor. These results indicated that bFGF enhanced the sugar-chain formation but did not affect their sulfation in endothelial GAG production. Similar changes were observed in either bovine aortic smooth-muscle cells and human fibroblastic IMR-90 cells to greater and lesser degrees, respectively. Characterization of GAGs in the endothelial cell layer and the conditioned medium revealed that bFGF enhanced both heparan sulfate and the other GAGs to a similar degree. The present data suggest that bFGF may be involved in the regulation of the blood coagulation system via altering GAGs of the vascular tissue when the endothelium was damaged.

Endothelial keratoplasty with infant donor tissue

PubMed Central

Kobayashi, Akira; Yokogawa, Hideaki; Yamazaki, Natsuko; Masaki, Toshinori; Sugiyama, Kazuhisa

2014-01-01

Here we report a case of endothelial keratoplasty with infant donor tissue obtained after brain death. A 52-year-old man with endothelial dysfunction of unknown cause in the right eye underwent non-Descemet stripping automated endothelial keratoplasty (nDSAEK) with tissue from an infant donor (2 years). Intraoperative and postoperative complications were recorded. Best corrected visual acuity and donor central endothelial cell density were recorded preoperatively and postoperatively. Infant donor tissue preparation with a microkeratome set at 300 μm was successful; the donor tissue was extremely elastic and soft compared with adult tissue. The central endothelial cell density of the infant donor tissue was as high as 4,291 cells/mm2. No complications were observed during donor tissue (8.0 mm in diameter) insertion with the double-glide technique (Busin glide with intraocular lens sheet glide) or any of the other procedures. Best corrected visual acuity improved from 1.7 logMAR (logarithm of the minimum angle of resolution; 0.02 decimal visual acuity) preoperatively to 0.2 logMAR (0.6) after 6 months and 0.1 logMAR (0.8) after 1 year. The central endothelial cell density after 6 months was 4,098 cells/mm2 (representing a 4.5% cell loss from preoperative donor cell measurements), and the central endothelial cell density after 1 year was 4,032 cells/mm2 (6.0% decrease). Infant donor tissue may be preferably used for DSAEK/nDASEK, since it may not be suitable for penetrating keratoplasty or Descemet membrane endothelial keratoplasty. PMID:25246761

Endothelial Progenitor Cells=EPC=Elemental Pernicious Complexity

PubMed Central

Ushio-Fukai, Masuko

2011-01-01

Abstract Endothelial progenitor cells (EPCs) represent a heterogeneous population of cells with a pro-angiogenic potential that are derived not only from bone marrow but also from other tissues. Depending on the model and cell type used, the pro-angiogenic effect is a consequence of direct vascular integration, the paracrine release of growth factors and cytokines, or complex interactions with other cellular components like monocytes or platelets. The pro-angiogenic potential of EPCs is dependent on the particular type of EPC studied and modulated by the risk and life style factors of the patient as well as by local factors determining the homing to diseased tissue and the EPC proteome. In this Forum on EPCs these aspects will be covered in individual review articles, which are accompanied by two original research studies on the role of NADPH oxidases for EPC mobilization and the impact of organic nitrates on EPCs. Antioxid. Redox Signal. 15, 911–914. PMID:21128729

Differential Effects of Leptin and Adiponectin in Endothelial Angiogenesis

PubMed Central

Adya, Raghu; Tan, Bee K.; Randeva, Harpal S.

2015-01-01

Obesity is a major health burden with an increased risk of cardiovascular morbidity and mortality. Endothelial dysfunction is pivotal to the development of cardiovascular disease (CVD). In relation to this, adipose tissue secreted factors termed “adipokines” have been reported to modulate endothelial dysfunction. In this review, we focus on two of the most abundant circulating adipokines, that is, leptin and adiponectin, in the development of endothelial dysfunction. Leptin has been documented to influence a multitude of organ systems, that is, central nervous system (appetite regulation, satiety factor) and cardiovascular system (endothelial dysfunction leading to atherosclerosis). Adiponectin, circulating at a much higher concentration, exists in different molecular weight forms, essentially made up of the collagenous fraction and a globular domain, the latter being investigated minimally for its involvement in proinflammatory processes including activation of NF-κβ and endothelial adhesion molecules. The opposing actions of the two forms of adiponectin in endothelial cells have been recently demonstrated. Additionally, a local and systemic change to multimeric forms of adiponectin has gained importance. Thus detailed investigations on the potential interplay between these adipokines would likely result in better understanding of the missing links connecting CVD, adipokines, and obesity. PMID:25650072

Increased expression of high mobility group box protein 1 and vascular endothelial growth factor in placenta previa.

PubMed

Xie, Han; Qiao, Ping; Lu, Yi; Li, Ying; Tang, Yuping; Huang, Yiying; Bao, Yirong; Ying, Hao

2017-12-01

Placenta previa is often associated with preterm delivery, reduced birth weight, a higher frequency of placental accreta and postpartum haemorrhage, and increased likelihood of blood transfusion. The present study aimed to examine the expression of high mobility group box protein 1 (HMGB1) in the placenta of women with or without placenta previa. The study group consisted of placental tissues obtained from women with or without placenta previa. The expression levels of HMGB1 and vascular endothelial growth factor (VEGF) were evaluated in the placental tissues using reverse transcription‑quantitative polymerase chain reaction, western blotting and immunohistochemistry. The mRNA expression levels of HMGB1 and VEGF were significantly increased in the placenta previa group compared with in the normal group. In addition, the placenta previa group exhibited increased HMGB1 and VEGF staining in vascular endothelial cells and trophoblasts. There were no significant differences in the expression of HMGB1 or VEGF between groups with or without placenta accreta or postpartum haemorrhage. The present study hypothesised that the increased expression of HMGB1 in the placenta may be associated with the pathogenesis of placenta previa by regulating the expression of the proangiogenic factor VEGF.

Tissue Vibration Induces Carotid Artery Endothelial Dysfunction: A Mechanism Linking Snoring and Carotid Atherosclerosis?

PubMed Central

Cho, Jin-Gun; Witting, Paul K.; Verma, Manisha; Wu, Ben J.; Shanu, Anu; Kairaitis, Kristina; Amis, Terence C.; Wheatley, John R.

2011-01-01

Study Objectives: We have previously identified heavy snoring as an independent risk factor for carotid atherosclerosis. In order to explore the hypothesis that snoring-associated vibration of the carotid artery induces endothelial dysfunction (an established atherogenic precursor), we utilized an animal model to examine direct effects of peri-carotid tissue vibration on carotid artery endothelial function and structure. Design: In supine anesthetized, ventilated rabbits, the right carotid artery (RCA) was directly exposed to vibrations for 6 h (peak frequency 60 Hz, energy matched to that of induced snoring in rabbits). Similarly instrumented unvibrated rabbits served as controls. Features of OSA such as hypoxemia, large intra-pleural swings and blood pressure volatility were prevented. Carotid endothelial function was then examined: (1) biochemically by measurement of tissue cyclic guanosine monophosphate (cGMP) to acetylcholine (ACh) and sodium nitroprusside (SNP); and (2) functionally by monitoring vessel relaxation with acetylcholine in a myobath. Measurement and Results: Vessel cGMP after stimulation with ACh was reduced in vibrated RCA compared with unvibrated (control) arteries in a vibration energy dose-dependent manner. Vibrated RCA also showed decreased vasorelaxation to ACh compared with control arteries. Notably, after addition of SNP (nitric oxide donor), cGMP levels did not differ between vibrated and control arteries, thereby isolating vibration-induced dysfunction to the endothelium alone. This dysfunction occurred in the presence of a morphologically intact endothelium without increased apoptosis. Conclusions: Carotid arteries subjected to 6 h of continuous peri-carotid tissue vibration displayed endothelial dysfunction, suggesting a direct plausible mechanism linking heavy snoring to the development of carotid atherosclerosis. Citation: Cho JG; Witting PK; Verma M; Wu BJ; Shanu A; Kairaitis K; Amis TC; Wheatley JR. Tissue vibration induces carotid artery endothelial dysfunction: a mechanism linking snoring and carotid atherosclerosis?. SLEEP 2011;34(6):751-757. PMID:21629363

MicroRNAs as Regulators of Endothelial Cell Functions in Cardiometabolic Diseases

PubMed Central

Araldi, Elisa; Suárez, Yajaira

2016-01-01

Endothelial cells (ECs) provide nutrients and oxygen essential for tissue homeostasis. Metabolic imbalances and other environmental stimuli, like cytokines or low shear stress, trigger endothelial inflammation, increase permeability, compromise vascular tone, promote cell proliferation and ultimately cause cell death. These factors contribute to EC dysfunction, which is crucial in the development of cardiometabolic diseases. microRNAs (miRNAs) are small non-coding RNAs that have important functions in the regulation of ECs. In the present review, we discuss the role of miRNAs in various aspects of EC pathology in cardiometabolic diseases like atherosclerosis, type 2 diabetes, obesity, and the metabolic syndrome, and in complication of those pathologies, like ischemia. We also discuss the potential therapeutic applications of miRNAs in promoting angiogenesis and neovascularization in tissues where the endothelium is damaged in different cardiometabolic diseases. PMID:26825686

Inhibition of TGF-β Signaling in SHED Enhances Endothelial Differentiation.

PubMed

Xu, J G; Gong, T; Wang, Y Y; Zou, T; Heng, B C; Yang, Y Q; Zhang, C F

2018-02-01

Low efficiency of deriving endothelial cells (ECs) from adult stem cells hampers their utilization in tissue engineering studies. The purpose of this study was to investigate whether suppression of transforming growth factor beta (TGF-β) signaling could enhance the differentiation efficiency of dental pulp-derived stem cells into ECs. We initially used vascular endothelial growth factor A (VEGF-A) to stimulate 2 dental pulp-derived stem cells (dental pulp stem cells and stem cells from human exfoliated deciduous teeth [SHED]) and compared their differentiation capacity into ECs. We further evaluated whether the vascular endothelial growth factor receptor I (VEGF-RI)-specific ligand placental growth factor-1 (PlGF-1) could mediate endothelial differentiation. Finally, we investigated whether the TGF-β signaling inhibitor SB-431542 could enhance the inductive effect of VEGF-A on endothelial differentiation, as well as the underlying mechanisms involved. ECs differentiated from dental pulp-derived stem cells exhibited the typical phenotypes of primary ECs, with SHED possessing a higher endothelial differentiation potential than dental pulp stem cells. VEGFR1-specific ligand-PLGF exerted a negligible effect on SHED-ECs differentiation. Compared with VEGF-A alone, the combination of VEGF-A and SB-431542 significantly enhanced the endothelial differentiation of SHED. The presence of SB-431542 inhibited the phosphorylation of Suppressor of Mothers Against Decapentaplegic 2/3 (SMAD2/3), allowing for VEGF-A-dependent phosphorylation and upregulation of VEGFR2. Our results indicate that the combination of VEGF-A and SB-431542 could enhance the differentiation of dental pulp-derived stem cells into endothelial cells, and this process is mediated through enhancement of VEGF-A-VEGFR2 signaling and concomitant inhibition of TGF-β-SMAD2/3 signaling.

Engineering a Microvascular Capillary Bed in a Tissue-Like Collagen Construct

PubMed Central

Unger, Ronald E.; Brochhausen, Christoph; Brown, Robert A.; Kirkpatrick, James C.

2014-01-01

Previous studies have shown that plastic compression (PC) of collagen gels allows a rapid and controlled fabrication of matrix- and cell-rich constructs in vitro that closely mimic the structure and characteristics of tissues in vivo. Microvascular endothelial cells, the major cell type making up the blood vessels in the body, were added to the PC collagen to determine whether cells attach, survive, grow, and express endothelial cell characteristics when seeded alone or in coculture with other cells. Endothelial cells seeded on the PC collagen containing human foreskin fibroblasts (HFF) or human osteoblasts (HOS) formed vessel-like structures over 3 weeks in culture without the addition of exogenous growth factors in the medium. In contrast, on the PC scaffolds without HFF or HOS, human dermal microvascular endothelial cells (HDMEC) exhibited a typical cobblestone morphology for 21 days under the same conditions. We propose that the coculture of primary endothelial cells with PC collagen constructs, containing a stromal cell population, is a valuable technique for in vitro modeling of proangiogenic responses toward such biomimetic constructs in vivo. A major observation in the cocultures was the absence of gel contraction, even after 3 weeks of fibroblast culture. This collagen form could, for example, be of great value in tissue engineering of the skin, as contractures are both aesthetically and functionally disabling. PMID:24684395

[Effect of vascular endothelial growth factor and tumor necrosis factor receptor for treatment of avascular necrosis of the femoral head in rabbits].

PubMed

Hu, Zhi-ming; Zhou, Ming-qian; Gao, Ji-min

2008-12-01

To evaluate the therapeutic effect of vascular endothelial growth factor (VEGF) and tumor necrosis factor receptor (TNFR) on avascular necrosis of the femoral head in rabbits. Avascular necrosis of the femoral head was induced in 26 New Zealand white rabbits by injections of horse serum and prednisolone. The rabbits were then divided into VEGF/TNFR treatment group, VEGF treatment group, and untreated model group, with another 4 normal rabbits as the normal control group. In the two treatment groups, the therapeutic agents were injected percutaneously into the femoral head. Enzyme-linked immunosorbent assay was performed to determine the concentration of TNF-alpha in rabbit serum followed by pathological examination of the changes in the bone tissues, bone marrow hematopoietic tissue and the blood vessels in the femoral head. Compared with the model group, the rabbits with both VEGF and TNFR treatment showed decreased serum concentration of TNF-alpha with obvious new vessel formation, decreased empty bone lacunae in the femoral head and hematopoietic tissue proliferation in the bone marrow cavity. Percutaneous injection of VEGF and TNFR into the femoral head can significantly enhance bone tissue angiogenesis and ameliorate osteonecrosis in rabbits with experimental femoral head necrosis.

Resveratrol, a polyphenolic compound found in wine, inhibits tissue factor expression in vascular cells : A possible mechanism for the cardiovascular benefits associated with moderate consumption of wine.

PubMed

Pendurthi, U R; Williams, J T; Rao, L V

1999-02-01

A number of studies suggest that moderate consumption of red wine may be more effective than other alcoholic beverages in decreasing the risk of coronary heart disease mortality. The phytochemical resveratrol found in wine, derived from grapes, has been thought to be responsible for cardiovascular benefits associated with wine consumption because it was shown to have antioxidant and antiplatelet activities. In the present investigation, we examined the effect of resveratrol on induction of tissue factor (TF) expression in vascular cells that were exposed to pathophysiological stimuli. The data presented herein show that resveratrol, in a dose-dependent manner, inhibited the expression of TF in endothelial cells stimulated with a variety of agonists, including interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNFalpha) and lipopolysaccharide (LPS). A similar inhibition of TF induction was also seen in LPS stimulated monocytes that were pretreated with resveratrol before their stimulation with LPS. In addition, resveratrol was shown to inhibit the LPS-induced expression of TNFalpha mRNA in endothelial cells and of TNFalpha and IL-1beta mRNA in monocytes. Nuclear run-on analysis in endothelial cells showed that resveratrol inhibited TF expression at the level of transcription. However, resveratrol did not significantly alter the binding of the transcription factors c-Fos/c-Jun and c-Rel/p65, the transcription factors required for the induction of TF promoter in both endothelial cells and monocytes. Similarly, resveratrol had no significant effect on the binding of NF-kappaB in endothelial cells stimulated with IL-1beta, TNFalpha, and LPS. Overall, our data show that resveratrol could effectively suppress the aberrant expression of TF and cytokines in vascular cells, but it requires further investigation to understand how resveratrol exerts its inhibitory effect.

Prothrombotic changes in diabetes mellitus.

PubMed

Morel, Olivier; Jesel, Laurence; Abbas, Malak; Morel, Nicolas

2013-07-01

Although our understanding of vascular pathology has greatly improved in recent years, the cellular and molecular mechanisms underlying the enhanced thrombotic propensity in type 2 diabetes mellitus (T2DM) remain incompletely characterized. Detrimental interactions between activated vascular cells (i.e., platelets, leukocytes, endothelial cells) and the vulnerable atheromatous plaque are a major determinant of the increased atherothrombotic burden in T2DM patients. Endothelial damage and accelerated senescence, impairment of the endothelial progenitor cell repair system, plaque neovascularization and inflammation, decreased clearance of detrimental molecules within the plaque, and increased expression of matrix metalloproteinases may collectively contribute to intraplaque hemorrhage and subsequent rupture. Notably, recent data demonstrates the central importance of the tissue factor-microparticle-mediated pathway in diabetic thrombophilia and cardiovascular complications. Acting as detrimental amplifiers of various biological responses (including thrombogenicity and plaque remodeling), microparticles have also emerged as a key marker of global vascular damage in T2DM patients. Available evidence suggests that targeting the tissue factor-microparticle pathway may be a promising approach for reducing the burden of the atherosclerotic complications of diabetes. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Expression of an insulin-regulatable glucose carrier in muscle and fat endothelial cells

NASA Astrophysics Data System (ADS)

Vilaró, Senen; Palacín, Manuel; Pilch, Paul F.; Testar, Xavier; Zorzano, Antonio

1989-12-01

INSULIN rapidly stimulates glucose use in the major target tissues, muscle and fat, by modulating a tissue-specific glucose transporter isoform1-6. Access of glucose to the target tissue is restricted by endothelial cells which line the walls of nonfenestrated capillaries of fat and muscle7. Thus, we examined whether the capillary endothelial cells are actively involved in the modulation of glucose availability by these tissues. We report here the abundant expression of the muscle/fat glucose transporter isoform in endothelial cells, using an immunocytochemical analysis with a monoclonal antibody specific for this isoform1. This expression is restricted to endothelial cells from the major insulin target tissues, and it is not detected in brain and liver where insulin does not activate glucose transport. The expression of the muscle/fat transporter isoform in endothelial cells is significantly greater than in the neighbouring muscle and fat cells. Following administration of insulin to animals in vivo, there occurs a rapid increase in the number of muscle/fat transporters present in the lumenal plasma membrane of the capillary endothelial cells. These results document that insulin promotes the translocation of the muscle/fat glucose transporter in endothelial cells. It is therefore likely that endothelial cells play an important role in the regulation of glucose use by the major insulin target tissues in normal and diseased states.

More than a biomarker: the systemic consequences of heparan sulfate fragments released during endothelial surface layer degradation (2017 Grover Conference Series)

PubMed Central

Oshima, Kaori; Haeger, Sarah M.; Hippensteel, Joseph A.; Herson, Paco S.

2017-01-01

Advances in tissue fixation and imaging techniques have yielded increasing appreciation for the glycosaminoglycan-rich endothelial glycocalyx and its in vivo manifestation, the endothelial surface layer (ESL). Pathological loss of the ESL during critical illness promotes local endothelial dysfunction and, consequently, organ injury. Glycosaminoglycan fragments, such as heparan sulfate, are released into the plasma of animals and humans after ESL degradation and have thus served as a biomarker of endothelial injury. The development of state-of-the-art glycomic techniques, however, has revealed that these circulating heparan sulfate fragments are capable of influencing growth factor and other signaling pathways distant to the site of ESL injury. This review summarizes the current state of knowledge concerning the local (i.e. endothelial injury) and systemic (i.e. para- or endocrine) consequences of ESL degradation and identifies opportunities for future, novel investigations. PMID:29199903

Granulocyte-Colony Stimulating Factor Receptor, Tissue Factor, and VEGF-R Bound VEGF in Human Breast Cancer In Loco.

PubMed

Wojtukiewicz, Marek Z; Sierko, Ewa; Skalij, Piotr; Kamińska, Magda; Zimnoch, Lech; Brekken, Ralf A; Thorpe, Philip E

2016-01-01

Doxorubicin and docetaxel-based chemotherapy regimens used in breast cancer patients are associated with high risk of febrile neutropenia (FN). Granulocyte colony-stimulating factors (G-CSF) are recommended for both treating and preventing chemotherapy-induced neutropenia. Increased thrombosis incidence in G-CSF treated patients was reported; however, the underlying mechanisms remain unclear. The principal activator of blood coagulation in cancer is tissue factor (TF). It additionally contributes to cancer progression and stimulates angiogenesis. The main proangiogenic factor is vascular endothelial growth factor (VEGF). The aim of the study was to evaluate granulocyte-colony stimulating factor receptor (G-CSFR), tissue factor (TF) expression and vascular endothelial growth factor receptor (VEGF-R) bound VEGF in human breast cancer in loco. G-CSFR, TF and VEGFR bound VEGF (VEGF: VEGFR) were assessed in 28 breast cancer tissue samples. Immunohistochemical (IHC) methodologies according to ABC technique and double staining IHC procedure were employed utilizing antibodies against G-CSFR, TF and VEGF associated with VEGFR (VEGF: VEGFR). Expression of G-CSFR was demonstrated in 20 breast cancer tissue specimens (71%). In 6 cases (21%) the expression was strong (IRS 9-12). Strong expression of TF was observed in all investigated cases (100%). Moreover, expression of VEGF: VEGFR was visualized in cancer cells (IRS 5-8). No presence of G-CSFR, TF or VEGF: VEGFR was detected on healthy breast cells. Double staining IHC studies revealed co-localization of G-CSFR and TF, G-CSFR and VEGF: VEGFR, as well as TF and VEGF: VEGFR on breast cancer cells and ECs. The results of the study indicate that GCSFR, TF and VEGF: VEGFR expression as well as their co-expression might influence breast cancer biology, and may increase thromboembolic adverse events incidence.

The skeletal vascular system - Breathing life into bone tissue.

PubMed

Stegen, Steve; Carmeliet, Geert

2017-08-26

During bone development, homeostasis and repair, a dense vascular system provides oxygen and nutrients to highly anabolic skeletal cells. Characteristic for the vascular system in bone is the serial organization of two capillary systems, each typified by specific morphological and physiological features. Especially the arterial capillaries mediate the growth of the bone vascular system, serve as a niche for skeletal and hematopoietic progenitors and couple angiogenesis to osteogenesis. Endothelial cells and osteoprogenitor cells interact not only physically, but also communicate to each other by secretion of growth factors. A vital angiogenic growth factor is vascular endothelial growth factor and its expression in skeletal cells is controlled by osteogenic transcription factors and hypoxia signaling, whereas the secretion of angiocrine factors by endothelial cells is regulated by Notch signaling, blood flow and possibly hypoxia. Bone loss and impaired fracture repair are often associated with reduced and disorganized blood vessel network and therapeutic targeting of the angiogenic response may contribute to enhanced bone regeneration. Copyright © 2017 Elsevier Inc. All rights reserved.

Expression of Biglycan in First Trimester Chorionic Villous Sampling Placental Samples and Altered Function in Telomerase-Immortalized Microvascular Endothelial Cells.

PubMed

Chui, Amy; Gunatillake, Tilini; Brennecke, Shaun P; Ignjatovic, Vera; Monagle, Paul T; Whitelock, John M; van Zanten, Dagmar E; Eijsink, Jasper; Wang, Yao; Deane, James; Borg, Anthony J; Stevenson, Janet; Erwich, Jan Jaap; Said, Joanne M; Murthi, Padma

2017-06-01

Biglycan (BGN) has reduced expression in placentae from pregnancies complicated by fetal growth restriction (FGR). We used first trimester placental samples from pregnancies with later small for gestational age (SGA) infants as a surrogate for FGR. The functional consequences of reduced BGN and the downstream targets of BGN were determined. Furthermore, the expression of targets was validated in primary placental endothelial cells isolated from FGR or control pregnancies. APPROACH AND RESULTS: BGN expression was determined using real-time polymerase chain reaction in placental tissues collected during chorionic villous sampling performed at 10 to 12 weeks' gestation from pregnancies that had known clinical outcomes, including SGA. Short-interference RNA reduced BGN expression in telomerase-immortalized microvascular endothelial cells, and the effect on proliferation, angiogenesis, and thrombin generation was determined. An angiogenesis array identified downstream targets of BGN, and their expression in control and FGR primary placental endothelial cells was validated using real-time polymerase chain reaction. Reduced BGN expression was observed in SGA placental tissues. BGN reduction decreased network formation of telomerase-immortalized microvascular endothelial cells but did not affect thrombin generation or cellular proliferation. The array identified target genes, which were further validated: angiopoetin 4 ( ANGPT4 ), platelet-derived growth factor receptor α ( PDGFRA ), tumor necrosis factor superfamily member 15 ( TNFSF15 ), angiogenin ( ANG ), serpin family C member 1 ( SERPIN1 ), angiopoietin 2 ( ANGPT2 ), and CXC motif chemokine 12 ( CXCL12 ) in telomerase-immortalized microvascular endothelial cells and primary placental endothelial cells obtained from control and FGR pregnancies. This study reports a temporal relationship between altered placental BGN expression and subsequent development of SGA. Reduction of BGN in vascular endothelial cells leads to disrupted network formation and alterations in the expression of genes involved in angiogenesis. Therefore, differential expression of these may contribute to aberrant angiogenesis in SGA pregnancies. © 2017 American Heart Association, Inc.

EGF and hydrocortisone as critical factors for the co-culture of adipogenic differentiated ASCs and endothelial cells.

PubMed

Volz, Ann-Cathrin; Huber, Birgit; Schwandt, Alina Maria; Kluger, Petra Juliane

In vitro composed vascularized adipose tissue is and will continue to be in great demand e.g. for the treatment of extensive high-graded burns or the replacement of tissue after tumor removal. Up to date, the lack of adequate culture conditions, mainly a culture medium, decelerates further achievements. In our study, we evaluated the influence of epidermal growth factor (EGF) and hydrocortisone (HC), often supplemented in endothelial cell (EC) specific media, on the co-culture of adipogenic differentiated adipose-derived stem cells (ASCs) and microvascular endothelial cells (mvECs). In ASCs, EGF and HC are thought to inhibit adipogenic differentiation and have lipolytic activities. Our results showed that in indirect co-culture for 14 days, adipogenic differentiated ASCs further incorporated lipids and partly gained an univacuolar morphology when kept in media with low levels of EGF and HC. In media with high EGF and HC levels, cells did not incorporate further lipids, on the contrary, cells without lipid droplets appeared. Glycerol release, to measure lipolysis, also increased with elevated amounts of EGF and HC in the culture medium. Adipogenic differentiated ASCs were able to release leptin in all setups. MvECs were functional and expressed the cell specific markers, CD31 and von Willebrand factor (vWF), independent of the EGF and HC content as long as further EC specific factors were present. Taken together, our study demonstrates that adipogenic differentiated ASCs can be successfully co-cultured with mvECs in a culture medium containing low or no amounts of EGF and HC, as long as further endothelial cell and adipocyte specific factors are available. Copyright © 2017 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

Eye-bank preparation of endothelial tissue.

PubMed

Boynton, Grace E; Woodward, Maria A

2014-07-01

Eye-bank preparation of endothelial tissue for keratoplasty continues to evolve. Although eye-bank personnel have become comfortable and competent at Descemet's stripping automated endothelial keratoplasty (DSAEK), tissue preparation and tissue transport, optimization of preparation methods continues. Surgeons and eye-bank personnel should be up to date on the research in the field. As surgeons transit to Descemet's membrane endothelial keratoplasty (DMEK), eye banks have risen to the challenge of preparing tissue. Eye banks are refining their DMEK preparation and transport techniques. This article covers refinements to DSAEK tissue preparation, innovations to prepare DMEK tissue, and nuances to improve donor cornea tissue quality. As eye bank-supplied corneal tissue is the main source of tissue for many corneal surgeons, it is critical to stay informed about tissue handling and preparation. Ultimately, the surgeon is responsible for the transplantation, so involvement of clinicians in eye-banking practices and advocacy for pursuing meaningful research in this area will benefit clinical patient outcomes.

Effects of antibodies to EG-VEGF on angiogenesis in the chick embryo chorioallantoic membrane.

PubMed

Feflea, Stefana; Cimpean, Anca Maria; Ceausu, Raluca Amalia; Gaje, Pusa; Raica, Marius

2012-01-01

Endocrine gland-related vascular endothelial growth factor (EG-VEGF), is an angiogenic factor specifically targeting endothelial cells derived from endocrine tissues. The inhibition of the EG-VEGF/prokineticin receptor pathway could represent a selective antiangiogenic and anticancer strategy. to evaluate the impact of an antibody to EG-VEGF on the rapidly growing capillary plexus of the chick embryo chorioallantoic membrane (CAM). The in ovo CAM assay was performed for the humanized EG-VEGF antibody. Hemorrhagic damage was induced in the capillaries, which led to early death of the embryos. Upon morphological staining, there was evidence of vascular disruption and extravasation of red blood cells in the chorion. Signs of vacuolization of the covering epithelium were also observed. Blocking endogenous EG-VEGF might represent a valuable approach of impairing or inhibiting angiogenesis in steroidogenic-derived embryonic tissues.

Plasmodium falciparum-infected erythrocytes induce Tissue Factor expression in endothelial cells and support the assembly of multimolecular coagulation complexes

PubMed Central

Francischetti, Ivo MB; Seydel, Karl B; Monteiro, Robson Q; Whitten, Richard O; Erexson, Cindy R; Noronha, Almério LL; Ostera, Graciela R.; Kamiza, Steve B; Molyneux, Malcolm E; Ward, Jerrold M; Taylor, Terrie E

2010-01-01

Summary Background Plasmodium falciparum malaria infects 300–500 million people every year causing 1–2 million deaths annually. Evidence of a coagulation disorder, activation of endothelial cells (EC) and increase in inflammatory cytokines are often present in malaria. Objectives We have asked whether parasitized red blood cells (pRBC) interaction with EC induces Tissue Factor expression in vitro and in vivo. The potential of phosphatidylserine-containing pRBC to support the assembly of blood coagulation complexes was also investigated. Results We demonstrate that mature forms of pRBC induce functional expression of tissue factor (TF) by endothelial cells (EC) in vitro with productive assembly of the extrinsic Xnase complex and initiation of the coagulation cascade. Late stage pRBC also support the prothrombinase and intrinsic Xnase complex formation in vitro, and may function as activated platelets in the amplification phase of the blood coagulation. Notably, postmortem brain sections obtained from P. falciparum-infected children who died from Cerebral Malaria and other causes display a consistent staining for TF in the EC. Conclusions These findings place TF expression by endothelium and the amplification of the coagulation cascade by pRBC and/or activated platelets as potentially critical steps in the pathogenesis of malaria. Furthermore, it may allow investigators to test other therapeutic alternatives targeting TF or modulators of EC function in the treatment of malaria and/or its complications. PMID:17002660

Enhanced expression by the brain matrix of P-glycoprotein in brain capillary endothelial cells.

PubMed

Tatsuta, T; Naito, M; Mikami, K; Tsuruo, T

1994-10-01

P-glycoprotein (PGP), an active efflux pump of antitumor agents in multidrug-resistant tumor cells, exists in brain capillary endothelium and could be functionally involved in the blood-brain barrier. To study the regulatory mechanism of PGP expression in brain capillary endothelium, various mouse tissue matrices were tested for their abilities to enhance the expression of PGP in mouse brain capillary endothelial cells (MBEC), which express relatively small amounts of PGP. Of the four tissue matrices we examined, PGP expression in MBEC cultured on the brain matrix increased 2.0-fold. The PGP-inducing activity was similarly detected in bovine brain matrix, and the activity was enriched in the fraction of pl 9.0 by isoelectric focusing. The fraction, named PIC-fraction (PGP-inducing component), increased the PGP expression in MBEC 3.5-fold. By Northern blot analysis, a 3.3-fold enhancement of mdr gene expression was observed in MBEC cultured on the PIC-fraction. The PGP-inducing activity of the PIC-fraction was reduced by the treatment with trypsin but not with collagenase, suggesting that a proteinaceous factor distinct from type I collagen might be responsible for the PGP-inducing activity of PIC-fraction. Although the PIC-fraction increased the PGP expression in other mouse brain capillary endothelial cells, the PIC-fraction did not increase PGP expression in mouse aortic endothelial cells and KB carcinoma cell lines expressing various amounts of PGP. These observations suggest that PGP expression in brain capillary endothelium is specifically regulated by a tissue-specific factor in the brain matrix.

The Interplay of Dental Pulp Stem Cells and Endothelial Cells in an Injectable Peptide Hydrogel on Angiogenesis and Pulp Regeneration In Vivo

PubMed Central

Dissanayaka, Waruna Lakmal; Hargreaves, Kenneth M.; Jin, Lijian; Samaranayake, Lakshman P.

2015-01-01

Securing an adequate blood supply for the survival of cell transplants is critical for a successful outcome in tissue engineering. Interactions between endothelial and progenitor/stem cells are important for vascularization of regenerating tissue. Recently, self-assembling peptide nanofibers were described as a promising environment for pulp regeneration due to their synthetic nature and controlled physicochemical properties. In this study, the peptide hydrogel PuraMatrix™ was used as a scaffold system to investigate the role of dental pulp stem cells (DPSCs) in triggering angiogenesis and the potential for regenerating vascularized pulp in vivo. Human umbilical vein endothelial cells (HUVECs), DPSCs, or cocultures of both cell types were encapsulated in three-dimensional PuraMatrix. The peptide nanofiber microenvironment supported cell survival, cell migration, and capillary network formation in the absence of exogenous growth factors. DPSCs increased early vascular network formation by facilitating the migration of HUVECs and by increasing vascular endothelial growth factor (VEGF) expression. Both the DPSC-monoculture and coculture groups exhibited vascularized pulp-like tissue with patches of osteodentin after transplantation in mice. The cocultured groups exhibited more extracellular matrix, vascularization, and mineralization than the DPSC-monocultures in vivo. The DPSCs play a critical role in initial angiogenesis, whereas coordinated efforts by the HUVECs and DPSCs are required to achieve a balance between extracellular matrix deposition and mineralization. The findings of this study also highlighted the importance of a microenvironment that supports cell–cell interactions and cell migration, which contribute to successful dental pulp regeneration. PMID:25203774

Fabrication of hydrogel based nanocomposite scaffold containing bioactive glass nanoparticles for myocardial tissue engineering.

PubMed

Barabadi, Zahra; Azami, Mahmoud; Sharifi, Esmaeel; Karimi, Roya; Lotfibakhshaiesh, Nasrin; Roozafzoon, Reza; Joghataei, Mohammad Taghi; Ai, Jafar

2016-12-01

Selecting suitable cell sources and angiogenesis induction are two important issues in myocardial tissue engineering. Human endometrial stromal cells (EnSCs) have been introduced as an abundant and easily available resource in regenerative medicine. Bioactive glass is an agent that induces angiogenesis and has been studied in some experiments. The aim of this study was to investigate in vitro differentiation capacity of endometrial stem cells into cardiomyocyte lineage and to evaluate capability of bioactive glass nanoparticles toward EnSCs differentiation into endothelial lineage and angiogenesis on hydrogel scaffold. Our findings suggests that endometrial stem cells could be programmed into cardiomyocyte linage and considered a suitable cell source for myocardial regeneration. This experiment also revealed that inclusion of bioactive glass nanoparticles in hydrogel scaffold could improve angiogenesis through differentiating EnSCs toward endothelial lineage and increasing level of vascular endothelial growth factor secretion. Copyright © 2016 Elsevier B.V. All rights reserved.

Targeted endothelial nanomedicine for common acute pathological conditions

PubMed Central

Shuvaev, Vladimir V.; Brenner, Jacob S.; Muzykantov, Vladimir R.

2017-01-01

Endothelium, a thin monolayer of specialized cells lining the lumen of blood vessels is the key regulatory interface between blood and tissues. Endothelial abnormalities are implicated in many diseases, including common acute conditions with high morbidity and mortality lacking therapy, in part because drugs and drug carriers have no natural endothelial affinity. Precise endothelial drug delivery may improve management of these conditions. Using ligands of molecules exposed to the bloodstream on the endothelial surface enables design of diverse targeted endothelial nanomedicine agents. Target molecules and binding epitopes must be accessible to drug carriers, carriers must be free of harmful effects, and targeting should provide desirable sub-cellular addressing of the drug cargo. The roster of current candidate target molecules for endothelial nanomedicine includes peptidases and other enzymes, cell adhesion molecules and integrins, localized in different domains of the endothelial plasmalemma and differentially distributed throughout the vasculature. Endowing carriers with an affinity to specific endothelial epitopes enables an unprecedented level of precision of control of drug delivery: binding to selected endothelial cell phenotypes, cellular addressing and duration of therapeutic effects. Features of nanocarrier design such as choice of epitope and ligand control delivery and effect of targeted endothelial nanomedicine agents. Pathological factors modulate endothelial targeting and uptake of nanocarriers. Selection of optimal binding sites and design features of nanocarriers are key controllable factors that can be iteratively engineered based on their performance from in vitro to pre-clinical in vivo experimental models. Targeted endothelial nanomedicine agents provide antioxidant, anti-inflammatory and other therapeutic effects unattainable by non-targeted counterparts in animal models of common acute severe human disease conditions. The results of animal studies provide the basis for the challenging translation endothelial nanomedicine into the clinical domain. PMID:26435455

Fibroblast Growth Factor Signaling Mediates Pulmonary Endothelial Glycocalyx Reconstitution

PubMed Central

Yang, Yimu; Haeger, Sarah M.; Suflita, Matthew A.; Zhang, Fuming; Dailey, Kyrie L.; Colbert, James F.; Ford, Joshay A.; Picon, Mario A.; Stearman, Robert S.; Lin, Lei; Liu, Xinyue; Han, Xiaorui; Linhardt, Robert J.

2017-01-01

The endothelial glycocalyx is a heparan sulfate (HS)–rich endovascular structure critical to endothelial function. Accordingly, endothelial glycocalyx degradation during sepsis contributes to tissue edema and organ injury. We determined the endogenous mechanisms governing pulmonary endothelial glycocalyx reconstitution, and if these reparative mechanisms are impaired during sepsis. We performed intravital microscopy of wild-type and transgenic mice to determine the rapidity of pulmonary endothelial glycocalyx reconstitution after nonseptic (heparinase-III mediated) or septic (cecal ligation and puncture mediated) endothelial glycocalyx degradation. We used mass spectrometry, surface plasmon resonance, and in vitro studies of human and mouse samples to determine the structure of HS fragments released during glycocalyx degradation and their impact on fibroblast growth factor receptor (FGFR) 1 signaling, a mediator of endothelial repair. Homeostatic pulmonary endothelial glycocalyx reconstitution occurred rapidly after nonseptic degradation and was associated with induction of the HS biosynthetic enzyme, exostosin (EXT)-1. In contrast, sepsis was characterized by loss of pulmonary EXT1 expression and delayed glycocalyx reconstitution. Rapid glycocalyx recovery after nonseptic degradation was dependent upon induction of FGFR1 expression and was augmented by FGF-promoting effects of circulating HS fragments released during glycocalyx degradation. Although sepsis-released HS fragments maintained this ability to activate FGFR1, sepsis was associated with the downstream absence of reparative pulmonary endothelial FGFR1 induction. Sepsis may cause vascular injury not only via glycocalyx degradation, but also by impairing FGFR1/EXT1–mediated glycocalyx reconstitution. PMID:28187268

Angiogenesis in mucous retention cyst: a human in vivo-like model of endothelial cell differentiation in mucous substrate.

PubMed

Swelam, Wael; Ida-Yonemochi, Hiroko; Saku, Takashi

2005-01-01

Mucous retention cysts contain a mucous pool in the lumina, in which pure angiogenic processes are occasionally observed. By using this unique human material, our aim was to understand the in vivo angiogenic process. Fifteen surgical tissue samples of mucous retention cysts of the lip were examined for expression of vascular endothelial markers and extracellular matrix molecules by immunohistochemistry and in situ hybridization (ISH). Endothelial cells forming new vascular channels showed immunopositivities for CD31, CD34, vascular endothelial growth factor (VEGF), and von Willebrand factor (vWF). These newly formed capillaries were surrounded by tenascin-positive matrices and further by a dense infiltration of CD68-positive cells with foamy to epitheloid appearances. Some of these cells were simultaneously positive for CD34, VEGF, and one of its receptors, Flk-1, and they showed definite mRNA as well as protein signals for tenascin. In addition, these cells often tended to be aligned, which suggested tubule formation. The results suggest that monocyte/macrophage lineage cells are a major source for endothelial cells at least in mucous retention cysts and that tenascin produced by those cells plays an important role in differentiation of endothelial cells.

Alginate Sulfates Mitigate Binding Kinetics of Proangiogenic Growth Factors with Receptors toward Revascularization.

PubMed

Schmidt, John; Lee, Min Kyung; Ko, Eunkyung; Jeong, Jae Hyun; DiPietro, Luisa A; Kong, Hyunjoon

2016-07-05

Ever since proangiogenic growth factors have been used as a vascular medicine to treat tissue ischemia, efforts have been increasingly made to develop a method to enhance efficacy of growth factors in recreating microvascular networks, especially at low dose. To this end, we hypothesized that polysaccharides substituted with sulfate groups would amplify growth factor receptor activation and stimulate phenotypic activities of endothelial cells involved in neovascularization. We examined this hypothesis by modifying alginate with a controlled number of sulfates and using it to derive a complex with vascular endothelial growth factor (VEGF), as confirmed with fluorescence resonance energy transfer (FRET) assay. Compared with the bare VEGF and with a mixture of VEGF and unmodified alginates, the VEGF complexed with alginate sulfates significantly reduced the dissociation rate with the VEGFR-2, elevated VEGFR-2 phosphorylation level, and increased the number of endothelial sprouts in vitro. Furthermore, the VEGF-alginate sulfate complex improved recovery of perfusion in an ischemic hindlimb of a mouse due to the increase of the capillary density. Overall, this study not only demonstrates an important cofactor of VEGF but also uncovers an underlying mechanism by which the cofactor mitigates the VEGF-induced signaling involved in the binding kinetics and activation of VEGFR. We therefore believe that the results of this study will be highly useful in improving the therapeutic efficacy of various growth factors and expediting their uses in clinical treatments of wounds and tissue defects.

Reduced endothelial activation after exercise is associated with improved HbA1c in patients with type 2 diabetes and coronary artery disease.

PubMed

Byrkjeland, Rune; Njerve, Ida U; Arnesen, Harald; Seljeflot, Ingebjørg; Solheim, Svein

2017-03-01

We have previously reported insignificant changes in HbA 1c after exercise in patients with both type 2 diabetes and coronary artery disease. In this study, we investigated the effect of exercise on endothelial function and possible associations between changes in endothelial function and HbA 1c . Patients with type 2 diabetes and coronary artery disease ( n = 137) were randomised to 12 months exercise or standard follow-up. Endothelial function was assessed by circulating biomarkers (E-selectin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, von Willebrand factor, tissue plasminogen activator antigen, asymmetric dimethylarginine and L-arginine/asymmetric dimethylarginine ratio). Differences between the randomised groups were analysed by analysis of covariance and correlations by Spearman's rho or Pearson's correlation. No effect of exercise on endothelial function was demonstrated. The changes in HbA 1c in the exercise group correlated with changes in E-selectin ( r = 0.56, p < 0.001), intercellular adhesion molecule-1 ( r = 0.27, p = 0.052), vascular cell adhesion molecule-1 ( r = 0.32, p = 0.022) and tissue plasminogen activator antigen ( r = 0.35, p =  0.011). HbA 1c decreased significantly more in patients with versus without a concomitant reduction in E-selectin ( p =  0.002), intercellular adhesion molecule-1 ( p =  0.011), vascular cell adhesion molecule-1 ( p =  0.028) and tissue plasminogen activator antigen ( p =  0.009). Exercise did not affect biomarkers of endothelial function in patients with both type 2 diabetes and coronary artery disease. However, changes in biomarkers of endothelial activation correlated with changes in HbA 1c , and reduced endothelial activation was associated with improved HbA 1c after exercise.

Vascular Endothelial Cell-Specific Connective Tissue Growth Factor (CTGF) Is Necessary for Development of Chronic Hypoxia-Induced Pulmonary Hypertension.

PubMed

Pi, Liya; Fu, Chunhua; Lu, Yuanquing; Zhou, Junmei; Jorgensen, Marda; Shenoy, Vinayak; Lipson, Kenneth E; Scott, Edward W; Bryant, Andrew J

2018-01-01

Chronic hypoxia frequently complicates the care of patients with interstitial lung disease, contributing to the development of pulmonary hypertension (PH), and premature death. Connective tissue growth factor (CTGF), a matricellular protein of the Cyr61/CTGF/Nov (CCN) family, is known to exacerbate vascular remodeling within the lung. We have previously demonstrated that vascular endothelial-cell specific down-regulation of CTGF is associated with protection against the development of PH associated with hypoxia, though the mechanism for this effect is unknown. In this study, we generated a transgenic mouse line in which the Ctgf gene was floxed and deleted in vascular endothelial cells that expressed Cre recombinase under the control of VE-Cadherin promoter (eCTGF KO mice). Lack of vascular endothelial-derived CTGF protected against the development of PH secondary to chronic hypoxia, as well as in another model of bleomycin-induced pulmonary hypertension. Importantly, attenuation of PH was associated with a decrease in infiltrating inflammatory cells expressing CD11b or integrin α M (ITGAM), a known adhesion receptor for CTGF, in the lungs of hypoxia-exposed eCTGF KO mice. Moreover, these pathological changes were associated with activation of-Rho GTPase family member-cell division control protein 42 homolog (Cdc42) signaling, known to be associated with alteration in endothelial barrier function. These data indicate that endothelial-specific deletion of CTGF results in protection against development of chronic-hypoxia induced PH. This protection is conferred by both a decrease in inflammatory cell recruitment to the lung, and a reduction in lung Cdc42 activity. Based on our studies, CTGF inhibitor treatment should be investigated in patients with PH associated with chronic hypoxia secondary to chronic lung disease.

Tumor Endothelial Cells

PubMed Central

Dudley, Andrew C.

2012-01-01

The vascular endothelium is a dynamic cellular “organ” that controls passage of nutrients into tissues, maintains the flow of blood, and regulates the trafficking of leukocytes. In tumors, factors such as hypoxia and chronic growth factor stimulation result in endothelial dysfunction. For example, tumor blood vessels have irregular diameters; they are fragile, leaky, and blood flow is abnormal. There is now good evidence that these abnormalities in the tumor endothelium contribute to tumor growth and metastasis. Thus, determining the biological basis underlying these abnormalities is critical for understanding the pathophysiology of tumor progression and facilitating the design and delivery of effective antiangiogenic therapies. PMID:22393533

THE ENDOTHELIUM IN SEPSIS

PubMed Central

Ince, Can; Mayeux, Philip R.; Nguyen, Trung; Gomez, Hernando; Kellum, John A.; Ospina-Tascón, Gustavo A.; Hernandez, Glenn; Murray, Patrick; De Backer, Daniel

2017-01-01

Sepsis affects practically all aspects of endothelial cell (EC) function and is thought to be the key factor in the progression from sepsis to organ failure. Endothelial functions affected by sepsis include vasoregulation, barrier function, inflammation, and hemostasis. These are among other mechanisms often mediated by glycocalyx shedding, such as abnormal nitric oxide metabolism, up-regulation of reactive oxygen species generation due to down-regulation of endothelial-associated antioxidant defenses, transcellular communication, proteases, exposure of adhesion molecules, and activation of tissue factor. This review covers current insight in EC-associated hemostatic responses to sepsis and the EC response to inflammation. The endothelial cell lining is highly heterogeneous between different organ systems and consequently also in its response to sepsis. In this context, we discuss the response of the endothelial cell lining to sepsis in the kidney, liver, and lung. Finally, we discuss evidence as to whether the EC response to sepsis is adaptive or maladaptive. This study is a result of an Acute Dialysis Quality Initiative XIV Sepsis Workgroup meeting held in Bogota, Columbia, between October 12 and 15, 2014. PMID:26871664

Dietary glutamine supplementation enhances endothelial progenitor cell mobilization in streptozotocin-induced diabetic mice subjected to limb ischemia.

PubMed

Su, Shiau-Tsz; Yeh, Chiu-Li; Hou, Yu-Chen; Pai, Man-Hui; Yeh, Sung-Ling

2017-02-01

Diabetes is a metabolic disorder with increased risk of vascular diseases. Tissue ischemia may occur with diabetic vascular complications. Bone marrow-derived endothelial progenitor cells (EPCs) constitute a reparative response to ischemic injury. This study investigated the effects of oral glutamine (GLN) supplementation on circulating EPC mobilization and expression of tissue EPC-releasing markers in diabetic mice subjected to limb ischemia. Diabetes was induced by a daily intraperitoneal injection of streptozotocin for 5 days. Diabetic mice were divided into 2 nonischemic groups and 6 ischemic groups. One of the nonischemic and 3 ischemic groups were fed the control diet, while the remaining 4 groups received diets with identical components except that part of the casein was replaced by GLN. The respective diets were fed to the mice for 3 weeks, and then the nonischemic mice were sacrificed. Unilateral hindlimb ischemia was created in the ischemic groups, and mice were sacrificed at 1, 7 or 21 days after ischemia. Their blood and ischemic muscle tissues were collected for further analyses. Results showed that plasma matrix metallopeptidase (MMP)-9 and the circulating EPC percentage increased after limb ischemia in a diabetic condition. Compared to groups without GLN, GLN supplementation up-regulated plasma stromal cell-derived factor (SDF)-1 and muscle MMP-9, SDF-1, hypoxia-inducible factor-1 and vascular endothelial growth factor gene expression. The CD31-immunoreactive intensities were also higher in the ischemic limb. These findings suggest that GLN supplementation enhanced circulating EPC mobilization that may promote endothelium repair at ischemic tissue in diabetic mice subjected to limb ischemia. Copyright © 2016 Elsevier Inc. All rights reserved.

The role of vascular endothelial growth factor-B in metabolic homoeostasis: current evidence.

PubMed

Zafar, Mohammad Ishraq; Zheng, Juan; Kong, Wen; Ye, Xiaofeng; Gou, Luoning; Regmi, Anita; Chen, Lu-Lu

2017-08-31

It has been shown that adipose tissue and skeletal muscles in lean individuals respond to meal-induced hyperinsulinemia by increase in perfusion, the effect not observed in patients with metabolic syndrome. In conditions of hyperglycaemia and hypertriglyceridemia, this insufficient vascularization leads to the liberation of reactive oxygen species (ROS), and disruption of nitric oxide (NO) synthesis and endothelial signalling responsible for the uptake of circulating fatty acids (FAs), whose accumulation in skeletal muscles and adipose tissue is widely associated with the impairment of insulin signalling. While the angiogenic role of VEGF-A and its increased circulating concentrations in obesity have been widely confirmed, the data related to the metabolic role of VEGF-B are diverse. However, recent discoveries indicate that this growth factor may be a promising therapeutic agent in patients with metabolic syndrome. Preclinical studies agree over two crucial metabolic effects of VEGF-B: (i) regulation of FAs uptake and (ii) regulation of tissue perfusion via activation of VEGF-A/vascular endothelial growth factor receptor (VEGFR) 2 (VEGFR2) pathway. While in some preclinical high-fat diet studies, VEGF-B overexpression reverted glucose intolerance and stimulated fat burning, in others it further promoted accumulation of lipids and lipotoxicity. Data from clinical studies point out the changes in circulating or tissue expression levels of VEGF-B in obese compared with lean patients. Potentially beneficial effects of VEGF-B, achieved through enhanced blood flow (increased availability of insulin and glucose uptake in target organs) and decreased FAs uptake (prevention of lipotoxicity and improved insulin signalling), and its safety for clinical use, remain to be clarified through future translational research. © 2017 The Author(s).

Histopathological and Immunohistochemical Evaluation of Pannus Tissue in Patients with Prosthetic Valve Dysfunction.

PubMed

Karakoyun, Süleyman; Ozan Gürsoy, Mustafa; Yesin, Mahmut; Kalçık, Macit; Astarcıoğlu, Mehmet Ali; Gündüz, Sabahattin; Emrah Oğuz, Ali; Çoban Kökten, Şermin; Nimet Karadayı, Ayşe; Tuncer, Altuğ; Köksal, Cengiz; Gökdeniz, Tayyar; Özkan, Mehmet

2016-01-01

Prosthetic valve dysfunction due to pannus formation is a rare but serious complication. Currently, limited data are available concerning the pathogenesis and immunohistochemical properties of pannus. The study aim was to investigate the morphological, histopathological and immunohistochemical characteristics of pannus formation in patients with prosthetic valve dysfunction. A total of 35 patients (10 males, 25 females; mean age 44 ± 16 years) who had undergone re-do valve surgery due to prosthetic valve obstruction was enrolled in the study. Immunohistochemical studies were aimed at evaluating the expression of alphasmooth muscle actin (α-SMA) and desmin in myofibroblasts and smooth muscle cells; epithelial membrane antigen (EMA) in epithelial cells; and CD34, Factor VIII and vascular endothelial growth factor (VEGF) in endothelial cells. Matrix metalloproteinases (MMPs) -2 and -9, and transforming growth factor-beta (TGF-β) were used to demonstrate cytokine release from macrophages, leukocytes, fibroblasts and myofibroblasts. Pannus appeared as a tough and thick tissue hyperplasia which began from outside the suture ring in the periannular region and extended to the inflow and outflow surfaces of the prosthetic valves. Histopathological analysis showed the pannus tissue to consist of chronic inflammatory cells (lymphocytes, plasma cells, macrophages and foreign body giant cells), spindle cells such as myofibroblasts, capillary blood vessels and endothelial cells laying down the lumens. Calcification was present in the pannus tissue of 19 explanted prostheses. Immunohistochemical studies revealed positive α-SMA expression in all patients, whereas 60.5% of patients were positive for desmin, 50% for EMA, 42.1% for VEGF, 39.5% for TBF-β, 42.1% for MMP-2, 86.8% for CD34, and 97.4% for Factor VIII. MMP-9 was negative in all patients. Pannus tissue appears to be formed as the result of a neointimal response in periannular regions of prosthetic valves that consist of periannular tissue migration, myofibroblast and extracellular matrix proliferation with vascular components. It is a chronic active process in which mediators such as TGF-β, VEGF and MMP-2 play roles in both matrix formation and degradation.

Targeting Heparin to Collagen within Extracellular Matrix Significantly Reduces Thrombogenicity and Improves Endothelialization of Decellularized Tissues.

PubMed

Jiang, Bin; Suen, Rachel; Wertheim, Jason A; Ameer, Guillermo A

2016-12-12

Thrombosis within small-diameter vascular grafts limits the development of bioartificial, engineered vascular conduits, especially those derived from extracellular matrix (ECM). Here we describe an easy-to-implement strategy to chemically modify vascular ECM by covalently linking a collagen binding peptide (CBP) to heparin to form a heparin derivative (CBP-heparin) that selectively binds a subset of collagens. Modification of ECM with CBP-heparin leads to increased deposition of functional heparin (by ∼7.2-fold measured by glycosaminoglycan composition) and a corresponding reduction in platelet binding (>70%) and whole blood clotting (>80%) onto the ECM. Furthermore, addition of CBP-heparin to the ECM stabilizes long-term endothelial cell attachment to the lumen of ECM-derived vascular conduits, potentially through recruitment of heparin-binding growth factors that ultimately improve the durability of endothelialization in vitro. Overall, our findings provide a simple yet effective method to increase deposition of functional heparin on the surface of ECM-based vascular grafts and thereby minimize thrombogenicity of decellularized tissue, overcoming a significant challenge in tissue engineering of bioartificial vessels and vascularized organs.

Alteration of human umbilical vein endothelial cell gene expression in different biomechanical environments.

PubMed

Shoajei, Shahrokh; Tafazzoli-Shahdpour, Mohammad; Shokrgozar, Mohammad Ali; Haghighipour, Nooshin

2014-05-01

Biomechanical environments affect the function of cells. In this study we analysed the effects of five mechanical stimuli on the gene expression of human umbilical vein endothelial cells (HUVECs) in mRNA level using real-time PCR. The following loading regimes were applied on HUVECs for 48 h: intermittent (0-5 dyn/cm(2) , 1 Hz) and uniform (5 dyn/cm(2) ) shear stresses concomitant by 10% intermittent equiaxial stretch (1 Hz), uniform shear stress alone (5 dyn/cm(2) ), and intermittent uniaxial and equiaxial stretches (10%, 1 Hz). A new bioreactor was made to apply uniform/cyclic shear and tensile loadings. Three endothelial suggestive specific genes (vascular endothelial growth factor receptor-2 (VEGFR-2, also known as FLK-1), von Willebrand Factor (vWF) and vascular endothelial-cadherin (VE-cadherin)), and two smooth muscle genes (α-smooth muscle actin (α-SMA) and smooth muscle myosin heavy chain (SMMHC)) were chosen for assessment of alteration in gene expression of endothelial cells and transdifferentiation toward smooth cells following load applications. Shear stress alone enhanced the endothelial gene expression significantly, while stretching alone was identified as a transdifferentiating factor. Cyclic equiaxial stretch contributed less to elevation of smooth muscle genes compared to uniaxial stretch. Cyclic shear stress in comparison to uniform shear stress concurrent with cyclic stretch was more influential on promotion of endothelial genes expression. Influence of different mechanical stimuli on gene expression may open a wider horizon to regulate functions of cell for tissue engineering purposes. © 2013 International Federation for Cell Biology.

Nerve Growth Factor-Induced Angiogenesis: 1. Endothelial Cell Tube Formation Assay.

PubMed

Lazarovici, Philip; Lahiani, Adi; Gincberg, Galit; Haham, Dikla; Fluksman, Arnon; Benny, Ofra; Marcinkiewicz, Cezary; Lelkes, Peter I

2018-01-01

Nerve growth factor (NGF) is a neurotrophin promoting survival, proliferation, differentiation, and neuroprotection in the embryonal and adult nervous system. NGF also induces angiogenic effects in the cardiovascular system, which may be beneficial in engineering new blood vessels and for developing novel anti-angiogenesis therapies for cancer. Angiogenesis is a cellular process characterized by a number of events, including endothelial cell migration, invasion, and assembly into capillaries. In vitro endothelial tube formation assays are performed using primary human umbilical vein endothelial cells, human aortic endothelial cells, and other human or rodent primary endothelial cells isolated from the vasculature of both tumors and normal tissues. Immortalized endothelial cell lines are also used for these assays. When seeded onto Matrigel, these cells reorganize to create tubelike structure, which may be used as models for studying some aspects of in vitro angiogenesis. Image acquisition by light and fluorescence microscopy and/or quantification of fluorescently labeled cells can be carried out manually or digitally, using commercial software and automated image processing. Here we detail materials, procedure, assay conditions, and cell labeling for quantification of endothelial cell tube formation. This model can be applied to study cellular and molecular mechanisms by which NGF or other neurotrophins promote angiogenesis. This model may also be useful for the development of potential angiogenic and/or anti-angiogenic drugs targeting NGF receptors.

Contribution of endothelial progenitors and proangiogenic hematopoietic cells to vascularization of tumor and ischemic tissue

PubMed Central

Kopp, Hans-Georg; Ramos, Carlos A.; Rafii, Shahin

2010-01-01

Purpose of review During the last several years, a substantial amount of evidence from animal as well as human studies has advanced our knowledge of how bone marrow derived cells contribute to neoangiogenesis. In the light of recent findings, we may have to redefine our thinking of endothelial cells as well as of perivascular mural cells. Recent findings Inflammatory hematopoietic cells, such as macrophages, have been shown to promote neoangiogenesis during tumor growth and wound healing. Dendritic cells, B lymphocytes, monocytes, and other immune cells have also been found to be recruited to neoangiogenic niches and to support neovessel formation. These findings have led to the concept that subsets of hematopoietic cells comprise proangiogenic cells that drive adult revascularization processes. While evidence of the importance of endothelial progenitor cells in adult vasculogenesis increased further, the role of these comobilized hematopoietic cells has been intensely studied in the last few years. Summary Angiogenic factors promote mobilization of vascular endothelial growth factor receptor 1-positive hematopoietic cells through matrix metalloproteinase-9 mediated release of soluble kit-ligand and recruit these proangiogenic cells to areas of hypoxia, where perivascular mural cells present stromal-derived factor 1 (CXCL-12) as an important retention signal. The same factors are possibly involved in mobilization of vascular endothelial growth factor receptor 2-positive endothelial precursors that may participate in neovessel formation. The complete characterization of mechanisms, mediators and signaling pathways involved in these processes will provide novel targets for both anti and proangiogenic therapeutic strategies. PMID:16567962

Over-expression of thymosin β4 in granulomatous lung tissue with active pulmonary tuberculosis.

PubMed

Kang, Yun-Jeong; Jo, Jin-Ok; Ock, Mee Sun; Yoo, Young-Bin; Chun, Bong-Kwon; Oak, Chul-Ho; Cha, Hee-Jae

2014-05-01

Recent studies have shown that thymosin β4 (Tβ4) stimulates angiogenesis by inducing vascular endothelial growth factor (VEGF) expression and stabilizing hypoxia inducible factor-1α (HIF-1α) protein. Pulmonary tuberculosis (TB), a type of granulomatous disease, is accompanied by intense angiogenesis and VEGF levels have been reported to be elevated in serum or tissue inflamed by pulmonary tuberculosis. We investigated the expression of Tβ4 in granulomatous lung tissues at various stages of active pulmonary tuberculosis, and we also examined the expression patterns of VEGF and HIF-1α to compare their Tβ4 expression patterns in patients' tissues and in the tissue microarray of TB patients. Tβ4 was highly expressed in both granulomas and surrounding lymphocytes in nascent granulomatous lung tissue, but was expressed only surrounding tissues of necrotic or caseous necrotic regions. The expression pattern of HIF-1α was similar to that of Tβ4. VEGF was expressed in both granulomas and blood vessels surrounding granulomas. The expression pattern of VEGF co-localized with CD31 (platelet endothelial cell adhesion molecule, PECAM-1), a blood endothelial cell marker, and partially co-localized with Tβ4. However, the expression of Tβ4 did not co-localize with alveolar macrophages. Stained alveolar macrophages were present surrounding regions of granuloma highly expressing Tβ4. We also analyzed mRNA expression in the sputum of 10 normal and 19 pulmonary TB patients. Expression of Tβ4 was significantly higher in patients with pulmonary tuberculosis than in normal controls. These data suggest that Tβ4 is highly expressed in granulomatous lung tissue with active pulmonary TB and is associated with HIF-1α- and VEGF-mediated inflammation and angiogenesis. Furthermore, the expression of Tβ4 in the sputum of pulmonary tuberculosis patients can be used as a potential marker for diagnosis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cell sheet engineering using the stromal vascular fraction of adipose tissue as a vascularization strategy.

PubMed

Costa, Marina; Cerqueira, Mariana T; Santos, Tírcia C; Sampaio-Marques, Belém; Ludovico, Paula; Marques, Alexandra P; Pirraco, Rogério P; Reis, Rui L

2017-06-01

Current vascularization strategies for Tissue Engineering constructs, in particular cell sheet-based, are limited by time-consuming and expensive endothelial cell isolation and/or by the complexity of using extrinsic growth factors. Herein, we propose an alternative strategy using angiogenic cell sheets (CS) obtained from the stromal vascular fraction (SVF) of adipose tissue that can be incorporated into more complex constructs. Cells from the SVF were cultured in normoxic and hypoxic conditions for up to 8days in the absence of extrinsic growth factors. Immunocytochemistry against CD31 and CD146 revealed spontaneous organization in capillary-like structures, more complex after hypoxic conditioning. Inhibition of HIF-1α pathway hindered capillary-like structure formation in SVF cells cultured in hypoxia, suggesting a role of HIF-1α. Moreover, hypoxic SVF cells showed a trend for increased secretion of angiogenic factors, which was reflected in increased network formation by endothelial cells cultured on matrigel using that conditioned medium. In vivo implantation of SVF CS in a mouse hind limb ischemia model revealed that hypoxia-conditioned CS led to improved restoration of blood flow. Both in vitro and in vivo data suggest that SVF CS can be used as simple and cost-efficient tools to promote functional vascularization of TE constructs. Neovascularization after implantation is a major obstacle for producing clinically viable cell sheet-based tissue engineered constructs. Strategies using endothelial cells and extrinsic angiogenic growth factors are expensive and time consuming and may raise concerns of tumorigenicity. In this manuscript, we describe a simplified approach using angiogenic cell sheets fabricated from the stromal vascular fraction of adipose tissue. The strong angiogenic behavior of these cell sheets, achieved without the use of external growth factors, was further stimulated by low oxygen culture. When implanted in an in vivo model of hind limb ischemia, the angiogenic cell sheets contributed to blood flux recovery. These cell sheets can therefore be used as a straightforward tool to increase the neovascularization of cell sheet-based thick constructs. Copyright © 2017. Published by Elsevier Ltd.

Adipose-derived cells.

PubMed

Meliga, Emanuele; Strem, Brian M; Duckers, H J; Serruys, Patrick W

2007-01-01

Heart failure is by far the most common cause of hospitalization in Western countries, with onerous economic consequences. Cell therapy holds great promise for use in tissue regeneration and is increasingly used in an effort to improve outcomes in cardiac disease. Recently it has been shown that adipose tissue, in addition to committed adipogenic, endothelial progenitor cells and pluripotent vascular progenitor cells, also contains multipotent cell types (adipose-derived stem cells, ADSCs) that, in cell culture conditions, have shown to have an impressive developmental plasticity including the ability to undergo multilineage differentiation and self-renewal. ADSCs express multiple CD marker antigens similar to those observed on MSCs and are also capable of secreting a large number of angiogenesis-related cytokines, including vascular endothelial growth factor, granulocyte/macrophage colony stimulating factor, stromal-derived factor-1alpha, and hepatocyte growth factor. Adipose tissue can be harvested in large quantities with minimal morbidity in several regions of the body and, on average, 100 ml of human adipose tissue yields about 1 x 10(6) stem cells. Studies conducted in porcine AMI models have shown a significant LV functional improvement, with no report of any potentially fatal arrhythmias. The APOLLO trial, a prospective, double blind, randomized, placebo-controlled trial currently in the recruiting phase, is a "first-in-man" study that explores the safety and feasibility of ADSC transplantation in patients with acute MI.

Dynamic regulation of canonical TGFβ signalling by endothelial transcription factor ERG protects from liver fibrogenesis.

PubMed

Dufton, Neil P; Peghaire, Claire R; Osuna-Almagro, Lourdes; Raimondi, Claudio; Kalna, Viktoria; Chuahan, Abhishek; Webb, Gwilym; Yang, Youwen; Birdsey, Graeme M; Lalor, Patricia; Mason, Justin C; Adams, David H; Randi, Anna M

2017-10-12

The role of the endothelium in protecting from chronic liver disease and TGFβ-mediated fibrosis remains unclear. Here we describe how the endothelial transcription factor ETS-related gene (ERG) promotes liver homoeostasis by controlling canonical TGFβ-SMAD signalling, driving the SMAD1 pathway while repressing SMAD3 activity. Molecular analysis shows that ERG binds to SMAD3, restricting its access to DNA. Ablation of ERG expression results in endothelial-to-mesenchymal transition (EndMT) and spontaneous liver fibrogenesis in EC-specific constitutive hemi-deficient (Erg cEC-Het ) and inducible homozygous deficient mice (Erg iEC-KO ), in a SMAD3-dependent manner. Acute administration of the TNF-α inhibitor etanercept inhibits carbon tetrachloride (CCL 4 )-induced fibrogenesis in an ERG-dependent manner in mice. Decreased ERG expression also correlates with EndMT in tissues from patients with end-stage liver fibrosis. These studies identify a pathogenic mechanism where loss of ERG causes endothelial-dependent liver fibrogenesis via regulation of SMAD2/3. Moreover, ERG represents a promising candidate biomarker for assessing EndMT in liver disease.The transcription factor ERG is key to endothelial lineage specification and vascular homeostasis. Here the authors show that ERG balances TGFβ signalling through the SMAD1 and SMAD3 pathways, protecting the endothelium from endothelial-to-mesenchymal transition and consequent liver fibrosis in mice via a SMAD3-dependent mechanism.

Adipose tissue-derived stem cells inhibit neointimal formation in a paracrine fashion in rat femoral artery.

PubMed

Takahashi, Masao; Suzuki, Etsu; Oba, Shigeyoshi; Nishimatsu, Hiroaki; Kimura, Kenjiro; Nagano, Tetsuo; Nagai, Ryozo; Hirata, Yasunobu

2010-02-01

Subcutaneous adipose tissue contains a lot of stem cells [adipose-derived stem cells (ASCs)] that can differentiate into a variety of cell lineages. In this study, we isolated ASCs from Wistar rats and examined whether ASCs would efficiently differentiate into vascular endothelial cells (ECs) in vitro. We also administered ASCs in a wire injury model of rat femoral artery and examined their effects. ASCs expressed CD29 and CD90, but not CD34, suggesting that ASCs resemble bone marrow-derived mesenchymal stem cells. When induced to differentiate into ECs with endothelial growth medium (EGM), ASCs expressed Flt-1, but not Flk-1 or mature EC markers such as CD31 and vascular endothelial cadherin. ASCs produced angiopoietin-1 when they were cultured in EGM. ASCs stimulated the migration of EC, as assessed by chemotaxis assay. When ASCs that were cultured in EGM were injected in the femoral artery, the ASCs potently and significantly inhibited neointimal formation without being integrated in the endothelial layer. EGM-treated ASCs significantly suppressed neointimal formation even when they were administered from the adventitial side. ASC administration significantly promoted endothelial repair. These results suggested that although ASCs appear to have little capacity to differentiate into mature ECs, ASCs have the potential to secrete paracrine factors that stimulate endothelial repair. Our results also suggested that ASCs inhibited neointimal formation via their paracrine effect of stimulation of EC migration in situ rather than the direct integration into the endothelial layer.

Role of Vascular Endothelial Growth Factor and Transforming Growth Factor-β2 in Rat Bone Tissue after Bone Fracture and Placement of Titanium Implants with Bioactive Bioresorbable Coatings.

PubMed

Kalinichenko, S G; Matveeva, N Yu; Kostiv, R E; Puz', A V

2017-03-01

The study established enhanced expression of vascular endothelial growth factor (VEGF) in the subpopulation of osteoblasts located in the regeneration region of femoral bone fracture near the titanium implants with bioactive calcium phosphate and hydroxyapatite coatings and suppressed activity of transforming growth factor-β2 (TGF-β2) in chondroblasts during the two weeks after surgery. In the delayed posttraumatic period, the distribution of TGF-β2 inversely related to its maximal activity. The data revealed the up-regulating effect of bioresorbable coatings on expression of VEGF and TGF-β2 and their implication in the control over various stages of reparative osteogenesis.

Eye-bank Preparation of Endothelial Tissue

PubMed Central

Boynton, Grace E.; Woodward, Maria A.

2014-01-01

Purpose of review Eyebank preparation of endothelial tissue for keratoplasty continues to evolve. While eye bank personnel have become comfortable and competent at Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) tissue preparation and tissue transport, optimization of preparation methods continues. Surgeons and eye bank personnel should be up to date on the research in the field. As surgeons transition to Descemet Membrane Endothelial Keratoplasty (DMEK), eye banks have risen to the challenge of preparing tissue. Eye banks are refining their DMEK preparation and transport techniques Recent findings This article covers refinements to DSAEK tissue preparation, innovations to prepare DMEK tissue, and nuances to improve donor cornea tissue quality. Summary As eye bank supplied corneal tissue is the main source of tissue for many corneal surgeons, it is critical to stay informed about tissue handling and preparation. Ultimately the surgeon is responsible for the transplantation, so involvement of clinicians in eye banking practices and advocacy for pursuing meaningful research in this area will benefit clinical patient outcomes. PMID:24837574

Human in vitro 3D co-culture model to engineer vascularized bone-mimicking tissues combining computational tools and statistical experimental approach.

PubMed

Bersini, Simone; Gilardi, Mara; Arrigoni, Chiara; Talò, Giuseppe; Zamai, Moreno; Zagra, Luigi; Caiolfa, Valeria; Moretti, Matteo

2016-01-01

The generation of functional, vascularized tissues is a key challenge for both tissue engineering applications and the development of advanced in vitro models analyzing interactions among circulating cells, endothelium and organ-specific microenvironments. Since vascularization is a complex process guided by multiple synergic factors, it is critical to analyze the specific role that different experimental parameters play in the generation of physiological tissues. Our goals were to design a novel meso-scale model bridging the gap between microfluidic and macro-scale studies, and high-throughput screen the effects of multiple variables on the vascularization of bone-mimicking tissues. We investigated the influence of endothelial cell (EC) density (3-5 Mcells/ml), cell ratio among ECs, mesenchymal stem cells (MSCs) and osteo-differentiated MSCs (1:1:0, 10:1:0, 10:1:1), culture medium (endothelial, endothelial + angiopoietin-1, 1:1 endothelial/osteo), hydrogel type (100%fibrin, 60%fibrin+40%collagen), tissue geometry (2 × 2 × 2, 2 × 2 × 5 mm(3)). We optimized the geometry and oxygen gradient inside hydrogels through computational simulations and we analyzed microvascular network features including total network length/area and vascular branch number/length. Particularly, we employed the "Design of Experiment" statistical approach to identify key differences among experimental conditions. We combined the generation of 3D functional tissue units with the fine control over the local microenvironment (e.g. oxygen gradients), and developed an effective strategy to enable the high-throughput screening of multiple experimental parameters. Our approach allowed to identify synergic correlations among critical parameters driving microvascular network development within a bone-mimicking environment and could be translated to any vascularized tissue. Copyright © 2015 Elsevier Ltd. All rights reserved.

Obesity-Induced Endoplasmic Reticulum Stress Causes Lung Endothelial Dysfunction and Promotes Acute Lung Injury.

PubMed

Shah, Dilip; Romero, Freddy; Guo, Zhi; Sun, Jianxin; Li, Jonathan; Kallen, Caleb B; Naik, Ulhas P; Summer, Ross

2017-08-01

Obesity is a significant risk factor for acute respiratory distress syndrome. The mechanisms underlying this association are unknown. We recently showed that diet-induced obese mice exhibit pulmonary vascular endothelial dysfunction, which is associated with enhanced susceptibility to LPS-induced acute lung injury. Here, we demonstrate that lung endothelial dysfunction in diet-induced obese mice coincides with increased endoplasmic reticulum (ER) stress. Specifically, we observed enhanced expression of the major sensors of misfolded proteins, including protein kinase R-like ER kinase, inositol-requiring enzyme α, and activating transcription factor 6, in whole lung and in primary lung endothelial cells isolated from diet-induced obese mice. Furthermore, we found that primary lung endothelial cells exposed to serum from obese mice, or to saturated fatty acids that mimic obese serum, resulted in enhanced expression of markers of ER stress and the induction of other biological responses that typify the lung endothelium of diet-induced obese mice, including an increase in expression of endothelial adhesion molecules and a decrease in expression of endothelial cell-cell junctional proteins. Similar changes were observed in lung endothelial cells and in whole-lung tissue after exposure to tunicamycin, a compound that causes ER stress by blocking N-linked glycosylation, indicating that ER stress causes endothelial dysfunction in the lung. Treatment with 4-phenylbutyric acid, a chemical protein chaperone that reduces ER stress, restored vascular endothelial cell expression of adhesion molecules and protected against LPS-induced acute lung injury in diet-induced obese mice. Our work indicates that fatty acids in obese serum induce ER stress in the pulmonary endothelium, leading to pulmonary endothelial cell dysfunction. Our work suggests that reducing protein load in the ER of pulmonary endothelial cells might protect against acute respiratory distress syndrome in obese individuals.

Comparison of skin microvascular reactivity with hemostatic markers of endothelial dysfunction and damage in type 2 diabetes

PubMed Central

Beer, Sandra; Feihl, François; Ruiz, Juan; Juhan-Vague, Irène; Aillaud, Marie-Françoise; Wetzel, Sandrine Golay; Liaudet, Lucas; Gaillard, Rolf C; Waeber, Bernard

2008-01-01

Aim: Patients with non-insulin-dependent diabetes mellitus (NIDDM) are at increased cardiovascular risk due to an accelerated atherosclerotic process. The present study aimed to compare skin microvascular function, pulse wave velocity (PWV), and a variety of hemostatic markers of endothelium injury [von Willebrand factor (vWF), plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (t-PA), tissue factor pathway inhibitor (TFPI), and the soluble form of thrombomodulin (s-TM)] in patients with NIDDM. Methods: 54 patients with NIDDM and 38 sex- and age-matched controls were studied. 27 diabetics had no overt micro- and/or macrovascular complications, while the remainder had either or both. The forearm skin blood flow was assessed by laser-Doppler imaging, which allowed the measurement of the response to iontophoretically applied acetylcholine (endothelium-dependent vasodilation) and sodium nitroprusside (endothelium-independent vasodilation), as well as the reactive hyperemia triggered by the transient occlusion of the circulation. Results: Both endothelial and non-endothelial reactivity were significantly blunted in diabetics, regardless of the presence or the absence of vascular complications. Plasma vWF, TFPI and s-TM levels were significantly increased compared with controls only in patients exhibiting vascular complications. Concentrations of t-PA and PAI-1 were significantly increased in the two groups of diabetics versus controls. Conclusion: In NIDDM, both endothelium-dependent and -independent microvascular skin reactivity are impaired, whether or not underlying vascular complications exist. It also appears that microvascular endothelial dysfunction is not necessarily associated in NIDDM with increased circulating levels of hemostatic markers of endothelial damage known to reflect a hypercoagulable state. PMID:19337558

Omega-3 Fatty acids and inflammation: novel interactions reveal a new step in neutrophil recruitment.

PubMed

Tull, Samantha P; Yates, Clara M; Maskrey, Benjamin H; O'Donnell, Valerie B; Madden, Jackie; Grimble, Robert F; Calder, Philip C; Nash, Gerard B; Rainger, G Ed

2009-08-01

Inflammation is a physiological response to tissue trauma or infection, but leukocytes, which are the effector cells of the inflammatory process, have powerful tissue remodelling capabilities. Thus, to ensure their precise localisation, passage of leukocytes from the blood into inflamed tissue is tightly regulated. Recruitment of blood borne neutrophils to the tissue stroma occurs during early inflammation. In this process, peptide agonists of the chemokine family are assumed to provide a chemotactic stimulus capable of supporting the migration of neutrophils across vascular endothelial cells, through the basement membrane of the vessel wall, and out into the tissue stroma. Here, we show that, although an initial chemokine stimulus is essential for the recruitment of flowing neutrophils by endothelial cells stimulated with the inflammatory cytokine tumour necrosis factor-alpha, transit of the endothelial monolayer is regulated by an additional and downstream stimulus. This signal is supplied by the metabolism of the omega-6-polyunsaturated fatty acid (n-6-PUFA), arachidonic acid, into the eicosanoid prostaglandin-D(2) (PGD(2)) by cyclooxygenase (COX) enzymes. This new step in the neutrophil recruitment process was revealed when the dietary n-3-PUFA, eicosapentaenoic acid (EPA), was utilised as an alternative substrate for COX enzymes, leading to the generation of PGD(3). This alternative series eicosanoid inhibited the migration of neutrophils across endothelial cells by antagonising the PGD(2) receptor. Here, we describe a new step in the neutrophil recruitment process that relies upon a lipid-mediated signal to regulate the migration of neutrophils across endothelial cells. PGD(2) signalling is subordinate to the chemokine-mediated activation of neutrophils, but without the sequential delivery of this signal, neutrophils fail to penetrate the endothelial cell monolayer. Importantly, the ability of the dietary n-3-PUFA, EPA, to inhibit this process not only revealed an unsuspected level of regulation in the migration of inflammatory leukocytes, it also contributes to our understanding of the interactions of this bioactive lipid with the inflammatory system. Moreover, it indicates the potential for novel therapeutics that target the inflammatory system with greater affinity and/or specificity than supplementing the diet with n-3-PUFAs.

Capture of endothelial cells under flow using immobilized vascular endothelial growth factor

PubMed Central

Smith, Randall J.; Koobatian, Maxwell T.; Shahini, Aref; Swartz, Daniel D.; Andreadis, Stelios T.

2015-01-01

We demonstrate the ability of immobilized vascular endothelial growth factor (VEGF) to capture endothelial cells (EC) with high specificity under fluid flow. To this end, we engineered a surface consisting of heparin bound to poly-L-lysine to permit immobilization of VEGF through the C-terminal heparin-binding domain. The immobilized growth factor retained its biological activity as shown by proliferation of EC and prolonged activation of KDR signaling. Using a microfluidic device we assessed the ability to capture EC under a range of shear stresses from low (0.5 dyne/cm2) to physiological (15 dyne/cm2). Capture was significant for all shear stresses tested. Immobilized VEGF was highly selective for EC as evidenced by significant capture of human umbilical vein and ovine pulmonary artery EC but no capture of human dermal fibroblasts, human hair follicle derived mesenchymal stem cells, or mouse fibroblasts. Further, VEGF could capture EC from mixtures with non-EC under low and high shear conditions as well as from complex fluids like whole human blood under high shear. Our findings may have far reaching implications, as they suggest that VEGF could be used to promote endothelialization of vascular grafts or neovascularization of implanted tissues by rare but continuously circulating EC. PMID:25771020

Development of In Vitro Embryo Production System Using Collagen Matrix Gel Attached with Vascular Endothelial Growth Factor Derived from Interleukin-1 Beta-Treated Porcine Endometrial Tissue.

PubMed

Han, Hye-In; Lee, Sang-Hee; Park, Choon-Keun

2017-07-01

The aim of this study was to establish an embryo culture system using collagen gel attached with vascular endothelial growth factor (VEGF) derived from interleukin-1 beta (IL-1β)-treated endometrial tissues from pigs. Endometria were separated from the porcine uterus at the follicular phase of the estrous cycle and were cultured with IL-1β. The collagen gels coincubated with IL-1β-treated endometria (C, without endometrial tissue; CE, with endometrial tissue; and CEI, IL-1β-treated endometrial tissue) were used for embryo culture. We found that, compared with the comparable figures in the control group, prostaglandin synthase-2 (PTGS-2) mRNA was increased in IL-1β-treated endometrial tissue (p < 0.05). The VEGF protein was not observed in collagen gel coincubated without endometrial tissue (C); however, it was detected in collagen gels coincubated with endometrial tissue (CE and CEI). The embryo cleavage rates and blastocyst formation did not differ among the treatment groups. The proportion of blastocysts did not differ among the groups. However, the number of blastocyst cells was significantly (p < 0.05) higher in the CEI group than in the other groups. These results clarify the effects of the intrauterine environment on preimplantation embryos and may be useful in research on the effects of extracellular matrix- and cytokine-treated endometrial tissue on embryo development.

Low Immunogenic Endothelial Cells Maintain Morphological and Functional Properties Required for Vascular Tissue Engineering.

PubMed

Lau, Skadi; Eicke, Dorothee; Carvalho Oliveira, Marco; Wiegmann, Bettina; Schrimpf, Claudia; Haverich, Axel; Blasczyk, Rainer; Wilhelmi, Mathias; Figueiredo, Constança; Böer, Ulrike

2018-03-01

The limited availability of native vessels suitable for the application as hemodialysis shunts or bypass material demands new strategies in cardiovascular surgery. Tissue-engineered vascular grafts containing autologous cells are considered ideal vessel replacements due to the low risk of rejection. However, endothelial cells (EC), which are central components of natural blood vessels, are difficult to obtain from elderly patients of poor health. Umbilical cord blood represents a promising alternative source for EC, but their allogeneic origin corresponds with the risk of rejection after allotransplantation. To reduce this risk, the human leukocyte antigen class I (HLA I) complex was stably silenced by lentiviral vector-mediated RNA interference (RNAi) in EC from peripheral blood and umbilical cord blood and vein. EC from all three sources were transduced by 93.1% ± 4.8% and effectively, HLA I-silenced by up to 67% compared to nontransduced (NT) cells or transduced with a nonspecific short hairpin RNA, respectively. Silenced EC remained capable to express characteristic endothelial surface markers such as CD31 and vascular endothelial cadherin important for constructing a tight barrier, as well as von Willebrand factor and endothelial nitric oxide synthase important for blood coagulation and vessel tone regulation. Moreover, HLA I-silenced EC were still able to align under unidirectional flow, to take up acetylated low-density lipoprotein, and to form capillary-like tube structures in three-dimensional fibrin gels similar to NT cells. In particular, addition of adipose tissue-derived mesenchymal stem cells significantly improved tube formation capability of HLA I-silenced EC toward long and widely branched vascular networks necessary for prevascularizing vascular grafts. Thus, silencing HLA I by RNAi represents a promising technique to reduce the immunogenic potential of EC from three different sources without interfering with EC-specific morphological and functional properties required for vascular tissue engineering. This extends the spectrum of available cell sources from autologous to allogeneic sources, thereby accelerating the generation of tissue-engineered vascular grafts in acute clinical cases.

[Pathogenesis of skin scleroderma--literature review].

PubMed

Wojas-Pelc, Anna; Lipko-Godlewska, Sylwia

2005-01-01

The pathogenesis of skin scleroderma (LS) is still unknown. Disturbances of vessels system, connective tissue metabolism and humoral and cellular immunological response is observed. Antinuclear antibodies are detected in 30-80% of patients with different types of skin scleroderma. They are present more often in patients with disseminated lesions and linear type of LS compared to morphoea au plaque. In our own analysis 28.5% of patients had also antibodies directed against Borrelia burgdorferi. It is believed that the injury of endothelial cells and proliferation in medial part of small vessels - which both lead to chronic ischemia - are the earliest disturbances observed in histopathological examination of the skin taken from systemic as well as from skin scleroderma patients. During last few years, there were some interesting reports concerning functional changes of endothelial cells which led to disturbances in tension of vessels smooth muscles. Free radicals - in genetically predispose people--can also provoke scleroderma lesions through their injury action on endothelial cells and stimulation of fibroblasts. In morphoea, the process of fibrosis begins around vessels. Deposition of connective tissue matrix is observed, especially collagen type I and III. This stimulation of fibroblasts as well as accumulation of connective tissue matrix are secondary to some stimulatory factors. These are: PDF, bFGF, TGFbeta and some cytokines. In morphoea patients serum levels of IL-1, IL-2, IL-4, IL-6 and IL-8 were elevated. In literature, levels and production of collagenases were decreased, although more authors say that tissue inhibitors of metalloproteinases are the main factor in fibrosis. The analysis of data tends to suspicion that enormous fibrosis observed in different types of scleroderma can be the result of increased production of collagen and other components of connective tissue as well as their incomplete degradation. Presented clinical and laboratory data show how many different factors influence etiopathogenesis of morphoea.

Live imaging of wound angiogenesis reveals macrophage orchestrated vessel sprouting and regression.

PubMed

Gurevich, David B; Severn, Charlotte E; Twomey, Catherine; Greenhough, Alexander; Cash, Jenna; Toye, Ashley M; Mellor, Harry; Martin, Paul

2018-06-04

Wound angiogenesis is an integral part of tissue repair and is impaired in many pathologies of healing. Here, we investigate the cellular interactions between innate immune cells and endothelial cells at wounds that drive neoangiogenic sprouting in real time and in vivo Our studies in mouse and zebrafish wounds indicate that macrophages are drawn to wound blood vessels soon after injury and are intimately associated throughout the repair process and that macrophage ablation results in impaired neoangiogenesis. Macrophages also positively influence wound angiogenesis by driving resolution of anti-angiogenic wound neutrophils. Experimental manipulation of the wound environment to specifically alter macrophage activation state dramatically influences subsequent blood vessel sprouting, with premature dampening of tumour necrosis factor-α expression leading to impaired neoangiogenesis. Complementary human tissue culture studies indicate that inflammatory macrophages associate with endothelial cells and are sufficient to drive vessel sprouting via vascular endothelial growth factor signalling. Subsequently, macrophages also play a role in blood vessel regression during the resolution phase of wound repair, and their absence, or shifted activation state, impairs appropriate vessel clearance. © 2018 The Authors. Published under the terms of the CC BY 4.0 license.

Crosstalk between reticular adherens junctions and platelet endothelial cell adhesion molecule-1 regulates endothelial barrier function.

PubMed

Fernández-Martín, Laura; Marcos-Ramiro, Beatriz; Bigarella, Carolina L; Graupera, Mariona; Cain, Robert J; Reglero-Real, Natalia; Jiménez, Anaïs; Cernuda-Morollón, Eva; Correas, Isabel; Cox, Susan; Ridley, Anne J; Millán, Jaime

2012-08-01

Endothelial cells provide a barrier between the blood and tissues, which is reduced during inflammation to allow selective passage of molecules and cells. Adherens junctions (AJ) play a central role in regulating this barrier. We aim to investigate the role of a distinctive 3-dimensional reticular network of AJ found in the endothelium. In endothelial AJ, vascular endothelial-cadherin recruits the cytoplasmic proteins β-catenin and p120-catenin. β-catenin binds to α-catenin, which links AJ to actin filaments. AJ are usually described as linear structures along the actin-rich intercellular contacts. Here, we show that these AJ components can also be organized in reticular domains that contain low levels of actin. Reticular AJ are localized in areas where neighboring cells overlap and encompass the cell adhesion receptor platelet endothelial cell adhesion molecule-1 (PECAM-1). Superresolution microscopy revealed that PECAM-1 forms discrete structures distinct from and distributed along AJ, within the voids of reticular domains. Inflammatory tumor necrosis factor-α increases permeability by mechanisms that are independent of actomyosin-mediated tension and remain incompletely understood. Reticular AJ, but not actin-rich linear AJ, were disorganized by tumor necrosis factor-α. This correlated with PECAM-1 dispersal from cell borders. PECAM-1 inhibition with blocking antibodies or small interfering RNA specifically disrupted reticular AJ, leaving linear AJ intact. This disruption recapitulated typical tumor necrosis factor-α-induced alterations of barrier function, including increased β-catenin phosphorylation, without altering the actomyosin cytoskeleton. We propose that reticular AJ act coordinately with PECAM-1 to maintain endothelial barrier function in regions of low actomyosin-mediated tension. Selective disruption of reticular AJ contributes to permeability increase in response to tumor necrosis factor-α.

The microenvironment of proliferative diabetic retinopathy supports lymphatic neovascularization.

PubMed

Gucciardo, Erika; Loukovaara, Sirpa; Korhonen, Ani; Repo, Pauliina; Martins, Beatriz; Vihinen, Helena; Jokitalo, Eija; Lehti, Kaisa

2018-06-01

Proliferative diabetic retinopathy (PDR) is a major diabetic microvascular complication characterized by pathological angiogenesis. Several retinopathy animal models have been developed to study the disease mechanisms and putative targets. However, knowledge on the human proliferative disease remains incomplete, relying on steady-state results from thin histological neovascular tissue sections and vitreous samples. New translational models are thus required to comprehensively understand the disease pathophysiology and develop improved therapeutic interventions. We describe here a clinically relevant model, whereby the native multicellular PDR landscape and neo(fibro)vascular processes can be analysed ex vivo and related to clinical data. As characterized by three-dimensional whole-mount immunofluorescence and electron microscopy, heterogeneity in patient-derived PDR neovascular tissues included discontinuous capillaries coupled with aberrantly differentiated, lymphatic-like and tortuous endothelia. Spatially confined apoptosis and proliferation coexisted with inflammatory cell infiltration and unique vascular islet formation. Ex vivo-cultured explants retained multicellularity, islet patterning and capillary or fibrotic outgrowth in response to vitreoretinal factors. Strikingly, PDR neovascular tissues, whose matched vitreous samples enhanced lymphatic endothelial cell sprouting, contained lymphatic-like capillaries in vivo and developed Prox1 + capillaries and sprouts with lymphatic endothelial ultrastructures ex vivo. Among multiple vitreal components, vascular endothelial growth factor C was one factor found at lymphatic endothelium-activating concentrations. These results indicate that the ischaemia-induced and inflammation-induced human PDR microenvironment supports pathological neolymphovascularization, providing a new concept regarding PDR mechanisms and targeting options. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

The SCL gene specifies haemangioblast development from early mesoderm.

PubMed

Gering, M; Rodaway, A R; Göttgens, B; Patient, R K; Green, A R

1998-07-15

The SCL gene encodes a basic helix-loop-helix (bHLH) transcription factor that is essential for the development of all haematopoietic lineages. SCL is also expressed in endothelial cells, but its function is not essential for specification of endothelial progenitors and the role of SCL in endothelial development is obscure. We isolated the zebrafish SCL homologue and show that it was co-expressed in early mesoderm with markers of haematopoietic, endothelial and pronephric progenitors. Ectopic expression of SCL mRNA in zebrafish embryos resulted in overproduction of common haematopoietic and endothelial precursors, perturbation of vasculogenesis and concomitant loss of pronephric duct and somitic tissue. Notochord and neural tube formation were unaffected. These results provide the first evidence that SCL specifies formation of haemangioblasts, the proposed common precursor of blood and endothelial lineages. Our data also underline the striking similarities between the role of SCL in haematopoiesis/vasculogenesis and the function of other bHLH proteins in muscle and neural development.

Neuropilin-1 Is Expressed on Lymphoid Tissue Residing LTi-like Group 3 Innate Lymphoid Cells and Associated with Ectopic Lymphoid Aggregates.

PubMed

Shikhagaie, Medya Mara; Björklund, Åsa K; Mjösberg, Jenny; Erjefält, Jonas S; Cornelissen, Anne S; Ros, Xavier Romero; Bal, Suzanne M; Koning, Jasper J; Mebius, Reina E; Mori, Michiko; Bruchard, Melanie; Blom, Bianca; Spits, Hergen

2017-02-14

Here, we characterize a subset of ILC3s that express Neuropilin1 (NRP1) and are present in lymphoid tissues, but not in the peripheral blood or skin. NRP1 + group 3 innate lymphoid cells (ILC3s) display in vitro lymphoid tissue inducer (LTi) activity. In agreement with this, NRP1 + ILC3s are mainly located in proximity to high endothelial venules (HEVs) and express cell surface molecules involved in lymphocyte migration in secondary lymphoid tissues via HEVs. NRP1 was also expressed on mouse fetal LTi cells, indicating that NRP1 is a conserved marker for LTi cells. Human NRP1 + ILC3s are primed cells because they express CD45RO and produce higher amounts of cytokines than NRP1 - cells, which express CD45RA. The NRP1 ligand vascular endothelial growth factor A (VEGF-A) served as a chemotactic factor for NRP1 + ILC3s. NRP1 + ILC3s are present in lung tissues from smokers and patients with chronic obstructive pulmonary disease, suggesting a role in angiogenesis and/or the initiation of ectopic pulmonary lymphoid aggregates. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Effect of living cellular sheets on the angiogenic potential of human microvascular endothelial cells.

PubMed

Villar, Cristina C; Zhao, Xiang R; Livi, Carolina B; Cochran, David L

2015-05-01

A fundamental issue limiting the efficacy of surgical approaches designed to correct periodontal mucogingival defects is that new tissues rely on limited sources of blood supply from the adjacent recipient bed. Accordingly, therapies based on tissue engineering that leverage local self-healing potential may represent promising alternatives for the treatment of mucogingival defects by inducing local vascularization. The aim of this study is to evaluate the effect of commercially available living cellular sheets (LCS) on the angiogenic potential of neonatal dermal human microvascular endothelial cells (HMVEC-dNeo). The effect of LCS on HMVEC-dNeo proliferation, migration, capillary tube formation, gene expression, and production of angiogenic factors was evaluated over time. LCS positively influenced HMVEC-dNeo proliferation and migration. Moreover, HMVEC-dNeo incubated with LCS showed transcriptional profiles different from those of untreated cells. Whereas increased expression of angiogenic genes predominated early on in response to LCS, late-phase responses were characterized by up- and downregulation of angiostatic and angiogenic genes. However, this trend was not confirmed at the protein level, as LCS induced increased production of most of the angiogenic factors tested (i.e., epidermal growth factor [EGF], heparin-binding EGF-like growth factor, interleukin 6, angiopoietin, platelet-derived growth factor-BB, placental growth factor, and vascular endothelial growth factor) throughout the investigational period. Finally, although LCS induced HMVEC-dNeo proliferation, migration, and expression of angiogenic factors, additional factors and environmental pressures are likely to be required to promote the development of complex, mesh-like vascular structures. LCS favor initial mechanisms that govern angiogenesis but failed to enhance or accelerate HMVEC-dNeo morphologic transition to complex vascular structures.

Stimulation of Transforming Growth Factor-β1-Induced Endothelial-To-Mesenchymal Transition and Tissue Fibrosis by Endothelin-1 (ET-1): A Novel Profibrotic Effect of ET-1.

PubMed

Wermuth, Peter J; Li, Zhaodong; Mendoza, Fabian A; Jimenez, Sergio A

2016-01-01

TGF-β-induced endothelial-to-mesenchymal transition (EndoMT) is a newly recognized source of profibrotic activated myofibroblasts and has been suggested to play a role in the pathogenesis of various fibrotic processes. Endothelin-1 (ET-1) has been implicated in the development of tissue fibrosis but its participation in TGF-β-induced EndoMT has not been studied. Here we evaluated the role of ET-1 on TGF-β1-induced EndoMT in immunopurified CD31+/CD102+ murine lung microvascular endothelial cells. The expression levels of α-smooth muscle actin (α-SMA), of relevant profibrotic genes, and of various transcription factors involved in the EndoMT process were assessed employing quantitative RT-PCR, immunofluorescence histology and Western blot analysis. TGF-β1 caused potent induction of EndoMT whereas ET-1 alone had a minimal effect. However, ET-1 potentiated TGF-β1-induced EndoMT and TGF-β1-stimulated expression of mesenchymal cell specific and profibrotic genes and proteins. ET-1 also induced expression of the TGF-β receptor 1 and 2 genes, suggesting a plausible autocrine mechanism to potentiate TGF-β-mediated EndoMT and fibrosis. Stimulation of TGF-β1-induced skin and lung fibrosis by ET-1 was confirmed in vivo in an animal model of TGF-β1-induced tissue fibrosis. These results suggest a novel role for ET-1 in the establishment and progression of tissue fibrosis.

Expression of Molecular Markers in Brain, Serum, and Lung Tissues Following Hypobaric Hypoxia

DTIC Science & Technology

2018-01-01

8 4.2 HIF-1α ELISA Results...9 4.3 Prolyl-4-hydroxylase Alpha Polypeptide I (P4Ha1) ELISA Results...10 4.4 Vascular Endothelial Growth Factor ELISA Results .......................................................12

Adipokines and the cardiovascular system: mechanisms mediating health and disease.

PubMed

Northcott, Josette M; Yeganeh, Azadeh; Taylor, Carla G; Zahradka, Peter; Wigle, Jeffrey T

2012-08-01

This review focuses on the role of adipokines in the maintenance of a healthy cardiovascular system, and the mechanisms by which these factors mediate the development of cardiovascular disease in obesity. Adipocytes are the major cell type comprising the adipose tissue. These cells secrete numerous factors, termed adipokines, into the blood, including adiponectin, leptin, resistin, chemerin, omentin, vaspin, and visfatin. Adipose tissue is a highly vascularised endocrine organ, and different adipose depots have distinct adipokine secretion profiles, which are altered with obesity. The ability of many adipokines to stimulate angiogenesis is crucial for adipose tissue expansion; however, excessive blood vessel growth is deleterious. As well, some adipokines induce inflammation, which promotes cardiovascular disease progression. We discuss how these 7 aforementioned adipokines act upon the various cardiovascular cell types (endothelial progenitor cells, endothelial cells, vascular smooth muscle cells, pericytes, cardiomyocytes, and cardiac fibroblasts), the direct effects of these actions, and their overall impact on the cardiovascular system. These were chosen, as these adipokines are secreted predominantly from adipocytes and have known effects on cardiovascular cells.

Accelerated wound healing of oral soft tissues and angiogenic effect induced by a pool of aminoacids combined to sodium hyaluronate (AMINOGAM).

PubMed

Favia, G; Mariggio, M A; Maiorano, F; Cassano, A; Capodiferro, S; Ribatti, D

2008-01-01

In this study we investigated the property of a new medical substance, in the form of a gel compound containing four aminoacids (glycine, leucine, proline, lysine) and sodium hyaluronate (AMINOGAM), to accelerate the wound healing process of the soft oral tissues and to promote angiogenesis in vivo in the vascular proliferation in chick embryo chorioallantoic membrane (CAM) assay. Furthermore, we investigated the capacity of AMINOGAM to induce the expression of an angiogenic cytokine, namely vascular endothelial growth factor (VEGF) in human fibroblasts in vitro. Results showed that AMINOGAM promoted wound healing in post-surgical wounds (after teeth extraction, oral laser surgery with secondary healing without direct suture of the surgical wound, and after dental implant insertion). Stimulated angiogenesis in vivo in the CAM assay and the response was similar to that obtained with vascular endothelial growth factor, a well-known angiogenic cytokine, tested in the same assay, and confirmed by clinical outcomes, which showed reduction of the healing time of oral soft tissues after three different kinds of surgery and also the absence of post-operative infections.

Neutrophil proteinase 3 (PR3) acts on protease-activated receptor-2 (PAR-2) to enhance vascular endothelial cell barrier function

PubMed Central

Kuckleburg, Christopher J.; Newman, Peter J.

2013-01-01

The principle role of the vascular endothelium is to present a semi-impermeable barrier to soluble factors and circulating cells, while still permitting the passage of leukocytes from the bloodstream into the tissue. The process of diapedesis involves the selective disruption of endothelial cell junctions, an event that could in theory compromise vascular integrity. It is therefore somewhat surprising that neutrophil transmigration does not significantly impair endothelial barrier function. We examined whether neutrophils might secrete factors that promote vascular integrity during the latter stages of neutrophil transmigration, and found that neutrophil proteinase 3 (PR3) – a serine protease harbored in azurophilic granules – markedly enhanced barrier function in endothelial cells. PR3 functioned in this capacity both in its soluble form and in a complex with cell-surface NB1. PR3-mediated enhancement of endothelial cell junctional integrity required its proteolytic activity, as well as endothelial cell expression of the protease-activated receptor, PAR-2. Importantly, PR3 suppressed the vascular permeability changes and disruption of junctional proteins induced by the action of PAR-1 agonists. These findings establish the potential for neutrophil-derived PR3 to play a role in reestablishing vascular integrity following leukocyte transmigration, and in protecting endothelial cells from PAR-1-induced permeability changes that occur during thrombotic and inflammatory events. PMID:23202369

STATs MEDIATE FIBROBLAST GROWTH FACTOR INDUCED VASCULAR ENDOTHELIAL MORPHOGENESIS

PubMed Central

Yang, Xinhai; Qiao, Dianhua; Meyer, Kristy; Friedl, Andreas

2009-01-01

The fibroblast growth factors (FGFs) play diverse roles in development, wound healing and angiogenesis. The intracellular signal transduction pathways which mediate these pleiotropic activities remain incompletely understood. We show here that the proangiogenic factors FGF2 and FGF8b can activate signal transducers and activators of transcription (STATs) in mouse microvascular endothelial cells. Both FGF2 and FGF8b activate STAT5 and to a lesser extent STAT1, but not STAT3. The FGF2-dependent activation of endothelial STAT5 was confirmed in vivo with the matrigel plug angiogenesis assay. In tissue samples of human gliomas, a tumor type where FGF-induced angiogenesis is important, STAT5 is detected in tumor vessel endothelial cell nuclei, consistent with STAT5 activation. By forced expression of constitutively active or dominant-negative mutant STAT5A in mouse brain endothelial cells, we further show that STAT5 activation is both necessary and sufficient for FGF-induced cell migration, invasion and tube formation, which are key events in vascular endothelial morphogenesis and angiogenesis. In contrast, STAT5 is not required for brain endothelial cell mitogenesis. The cytoplasmic tyrosine kinases Src and Janus kinase 2 (Jak2) both appear to be involved in the activation of STAT5, as their inhibition reduces FGF2 and FGF8b induced STAT5 phosphorylation and endothelial cell tube formation. Constitutively active STAT5A partially restores tube formation in the presence of Src or Jak2 inhibitors. These observations demonstrate that FGFs utilize distinct signaling pathways to induce angiogenic phenotypes. Together, our findings implicate the FGF-Jak2/Src-STAT5 cascade as a critical angiogenic FGF signaling pathway. PMID:19176400

Upcyte® Microvascular Endothelial Cells Repopulate Decellularized Scaffold

PubMed Central

Dally, Iris; Hartmann, Nadja; Münst, Bernhard; Braspenning, Joris; Walles, Heike

2013-01-01

A general problem in tissue engineering is the poor and insufficient blood supply to guarantee tissue cell survival as well as physiological tissue function. To address this limitation, we have developed an in vitro vascularization model in which a decellularized porcine small bowl segment, representing a capillary network within a collagen matrix (biological vascularized scaffold [BioVaSc]), is reseeded with microvascular endothelial cells (mvECs). However, since the supply of mvECs is limited, in general, and as these cells rapidly dedifferentiate, we have applied a novel technology, which allows the generation of large batches of quasi-primary cells with the ability to proliferate, whilst maintaining their differentiated functionality. These so called upcyte mvECs grew for an additional 15 population doublings (PDs) compared to primary cells. Upcyte mvECs retained endothelial characteristics, such as von Willebrandt Factor (vWF), CD31 and endothelial nitric oxide synthase (eNOS) expression, as well as positive Ulex europaeus agglutinin I staining. Upcyte mvECs also retained biological functionality such as tube formation, cell migration, and low density lipoprotein (LDL) uptake, which were still evident after PD27. Initial experiments using MTT and Live/Dead staining indicate that upcyte mvECs repopulate the BioVaSc Scaffold. As with conventional cultures, these cells also express key endothelial molecules (vWF, CD31, and eNOS) in a custom-made bioreactor system even after a prolonged period of 14 days. The combination of upcyte mvECs and the BioVaSc represents a novel and promising approach toward vascularizing bioreactor models which can better reflect organs, such as the liver. PMID:22799502

Structure and Function of the Splice Variants of TMPRSS2-ERG, a Prevalent Genomic Alteration in Prostate Cancer

DTIC Science & Technology

2011-09-01

the ETS family of transcription factors showing diverse expression patterns in human tissues (Turner and Watson, 2008). ERG, similar to other...and adult mouse tissues . Most striking of these observations was highly selective and abundant expression of erg protein in endothelial cells of...mouse tissues . We for the first time clarified that endogenous ERG was not expressed in normal mouse prostate epithelium (Mohamed et al., 2010

Endothelial Microparticles From Acute Coronary Syndrome Patients Induce Premature Coronary Artery Endothelial Cell Aging and Thrombogenicity: Role of the Ang II/AT1 Receptor/NADPH Oxidase-Mediated Activation of MAPKs and PI3-Kinase Pathways.

PubMed

Abbas, Malak; Jesel, Laurence; Auger, Cyril; Amoura, Lamia; Messas, Nathan; Manin, Guillaume; Rumig, Cordula; León-González, Antonio J; Ribeiro, Thais P; Silva, Grazielle C; Abou-Merhi, Raghida; Hamade, Eva; Hecker, Markus; Georg, Yannick; Chakfe, Nabil; Ohlmann, Patrick; Schini-Kerth, Valérie B; Toti, Florence; Morel, Olivier

2017-01-17

Microparticles (MPs) have emerged as a surrogate marker of endothelial dysfunction and cardiovascular risk. This study examined the potential of MPs from senescent endothelial cells (ECs) or from patients with acute coronary syndrome (ACS) to promote premature EC aging and thrombogenicity. Primary porcine coronary ECs were isolated from the left circumflex coronary artery. MPs were prepared from ECs and venous blood from patients with ACS (n=30) and from healthy volunteers (n=4) by sequential centrifugation. The level of endothelial senescence was assessed as senescence-associated β-galactosidase activity using flow cytometry, oxidative stress using the redox-sensitive probe dihydroethidium, tissue factor activity using an enzymatic Tenase assay, the level of target protein expression by Western blot analysis, platelet aggregation using an aggregometer, and shear stress using a cone-and-plate viscometer. Senescence, as assessed by senescence-associated β-galactosidase activity, was induced by the passaging of porcine coronary artery ECs from passage P1 to P4, and was associated with a progressive shedding of procoagulant MPs. Exposure of P1 ECs to MPs shed from senescent P3 cells or circulating MPs from ACS patients induced increased senescence-associated β-galactosidase activity, oxidative stress, early phosphorylation of mitogen-activated protein kinases and Akt, and upregulation of p53, p21, and p16. Ex vivo, the prosenescent effect of circulating MPs from ACS patients was evidenced only under conditions of low shear stress. Depletion of endothelial-derived MPs from ACS patients reduced the induction of senescence. Prosenescent MPs promoted EC thrombogenicity through tissue factor upregulation, shedding of procoagulant MPs, endothelial nitric oxide synthase downregulation, and reduced nitric oxide-mediated inhibition of platelet aggregation. These MPs exhibited angiotensin-converting enzyme activity and upregulated AT1 receptors and angiotensin-converting enzyme in P1 ECs. Losartan, an AT1 receptor antagonist, and inhibitors of either mitogen-activated protein kinases or phosphoinositide 3-kinase prevented the MP-induced endothelial senescence. These findings indicate that endothelial-derived MPs from ACS patients induce premature endothelial senescence under atheroprone low shear stress and thrombogenicity through angiotensin II-induced redox-sensitive activation of mitogen-activated protein kinases and phosphoinositide 3-kinase/Akt. They further suggest that targeting endothelial-derived MP shedding and their bioactivity may be a promising therapeutic strategy to limit the development of an endothelial dysfunction post-ACS. © 2016 American Heart Association, Inc.

Biomimetic transport and rational drug delivery.

PubMed

Ranney, D F

2000-01-15

Medicine and pharmaceutics are encountering critical needs and opportunities for transvascular drug delivery that improves site targeting and tissue permeation by mimicking natural tissue addressing and transport mechanisms. This is driven by the accelerated development of genomic agents requiring targeted controlled release. Although rationally designed for in vitro activity, such agents are not highly effective in vivo, due to opsonization and degradation by plasma constituents, and failure to transport across the local vascular endothelium and tissue matrix. A growing knowledge of the addresses of the body can be applied to engineer "Bio-Logically" staged delivery systems with sequential bioaddressins complementary to the discontinuous compartments encountered--termed discontinuum pharmaceutics. Effective tissue targeting is accomplished by leukocytes, bacteria, and viruses. We are increasingly able to mimic their bioaddressins by genomic means. Approaches described in this commentary include: (a) endothelial-directed adhesion mediated by oligosaccharides and carbohydrates (e.g. dermatan sulfate as a mimic of sulfated CD44) and peptidomimetics interacting with adhesins, selectins, integrins, hyaluronans, and locally induced growth factors (e.g. vascular endothelial growth factor, VEGF) and coagulation factors (e.g. factor VIII antigen); (b) improved tissue permeation conferred by hydrophilically "cloaked" carrier systems; (c) "uncloaking" by matrix dilution or selective triggering near the target cells; and (d) target binding-internalization by terminally exposed hydrophobic moieties, cationic polymers, and receptor-binding lectins, peptides, or carbohydrates. This commentary also describes intermediate technology solutions (e.g. "hybrid drugs"), and highlights the high-resolution, dynamic magnetic resonance imaging and radiopharmaceutical imaging technologies plus the groups and organizations capable of accelerating these important initiatives.

Preliminary results comparing the recovery of basic fibroblast growth factor (FGF-2) in adipose tissue and benign and malignant renal tissue.

PubMed

Mydlo, J H; Kral, J G; Macchia, R J

1998-06-01

Basic fibroblast growth factor (bFGF or FGF-2) is mitogenic to numerous epithelial, mesodermal and endothelial cells, and thus may play a role in the neovascularity and progression of several tumors. Furthermore, FGF-2 is reported to be elevated in the serum and urine of patients with various cancers, including renal cancer. Obesity, with increased body fat, is a risk factor for renal cancer through unknown mechanisms. Since adipose tissue is a source of FGF-2, we determined the quantity and quality of activity of FGF-2 in omental adipose tissue and compared it to normal and cancerous renal tissue. Using heparin-Sepharose chromatography we extracted proteins from human omental adipose tissue, renal cell carcinoma (RCC) and benign renal tissue (BRT). Using FGF-2 antisera we performed western blot analysis to confirm their homology to FGF-2. We also assessed recovery, mitogenicity and angiogenicity of each of the proteins using thymidine incorporation into human umbilical vein endothelial cells (HUVEC) and the chorioallantoic membrane (CAM) assay. Each of the three purified mitogenic proteins eluted with NaCl concentrations between 1.4 M. and 1.8 M., similar to control FGF-2. There was greater recovery of FGF-2 from omental adipose tissue compared with renal cell carcinoma or benign renal tissue (42 microg. vs. 24 microg. and 18 microg., respectively; ANOVA p <0.05). Moreover, FGF-2 from adipose tissue had greater mitogenic activity (96.% versus 68% and 38%; p <0.05) and greater angiogenic activity (5.5 vessels versus 2.7 and 1.6 vessels; p <0.05) on the CAM assay. We suggest that human omental adipose tissue FGF-2 may demonstrate greater mitogenic and angiogenic activity than either benign or cancerous renal tissue FGF-2. It is not known if FGF-2 from adipose tissue may play a role in the relationship between obesity and renal cancer.

Febuxostat attenuates paroxysmal atrial fibrillation-induced regional endothelial dysfunction.

PubMed

Li, YanGuang; Chen, FuKun; Deng, Long; Lin, Kun; Shi, Xiangmin; Zhaoliang, Shan; Wang, YuTang

2017-01-01

Paroxysmal atrial fibrillation (PAF) can increase thrombogenesis risk, especially in the left atrium (LA). The exact mechanism is still unclear. We assessed the effects of PAF on endothelial function, and investigated if febuxostat (FX) can attenuate endothelial dysfunction by inhibition of xanthine oxidase (XO). Eighteen male New Zealand white rabbits were divided randomly into sham-operated (S), PAF (P) or FX+pacing (FP) groups. Group P and group FP received rapid atrial pacing (RAP). Group FP was administered febuxostat (FX) for 7days before RAP. Post-procedure, blood samples were collected from the LA, right atrium (RA) and peripheral circulation. Tissues from the LA and RA were obtained. Endothelial dysfunction (thrombomodulin [TM], von Willebrand factor [VWF], asymmetric dimethylarginine [ADMA]), and indirect thrombin generation (thrombin-antithrombin complex [TAT], prothrombin fragment 1+2 [F1.2]) and oxidative stress in atrial tissue (xanthine oxidase [XO], superoxide dismutase [SOD], malondialdehyde [MDA]) were measured using an Enzyme-linked immunosorbent assay. Atrial endothelial expression of TM and VWF was measured by histology/western blotting. Endothelial dysfunction (TM, VWF, ADMA), TAT generation and oxidative stress (XO, SOD, MDA) in group P were more significant compared with that in group S (p<0.05, respectively). In group P, all of these changes occurred to a greater extent in the LA compared with those in the RA or peripheral circulation. In group FP, FX attenuated endothelial dysfunction and reduced TAT levels by inhibition of XO-mediated oxidative stress. PAF can lead to endothelial dysfunction and TAT generation by XO-mediated oxidative stress. The LA is more susceptible to these effects. FX can attenuate these changes by inhibition XO and XO-mediated oxidative stress. Copyright © 2016. Published by Elsevier Ltd.

FGF-dependent metabolic control of vascular development

PubMed Central

Yu, Pengchun; Alves, Tiago C.; Fang, Jennifer S.; Xie, Yi; Zhu, Jie; Chen, Zehua; De Smet, Frederik; Zhang, Jiasheng; Jin, Suk-Won; Sun, Lele; Sun, Hongye; Kibbey, Richard G.; Hirschi, Karen K.; Hay, Nissim; Carmeliet, Peter; Chittenden, Thomas W.; Eichmann, Anne; Potente, Michael; Simons, Michael

2017-01-01

Blood and lymphatic vasculatures are intimately involved in tissue oxygenation and fluid homeostasis maintenance. Assembly of these vascular networks involves sprouting, migration and proliferation of endothelial cells. Recent studies have suggested that changes in cellular metabolism are of importance to these processes1. While much is known about vascular endothelial growth factor (VEGF)-dependent regulation of vascular development and metabolism2,3, little is understood about the role of fibroblast growth factors (FGFs) in this context4. Here we identify FGF receptor (FGFR) signaling as a critical regulator of vascular development. This is achieved by FGF-dependent control of c-MYC (MYC) expression that, in turn, regulates expression of the glycolytic enzyme hexokinase 2 (HK2). A decrease in HK2 levels in the absence of FGF signaling inputs results in decreased glycolysis leading to impaired endothelial cell proliferation and migration. Pan-endothelial- and lymphatic-specific Hk2 knockouts phenocopy blood and/or lymphatic vascular defects seen in Fgfr1/r3 double mutant mice while HK2 overexpression partially rescues the defects caused by suppression of FGF signaling. Thus, FGF-dependent regulation of endothelial glycolysis is a pivotal process in developmental and adult vascular growth and development. PMID:28467822

FGF-dependent metabolic control of vascular development.

PubMed

Yu, Pengchun; Wilhelm, Kerstin; Dubrac, Alexandre; Tung, Joe K; Alves, Tiago C; Fang, Jennifer S; Xie, Yi; Zhu, Jie; Chen, Zehua; De Smet, Frederik; Zhang, Jiasheng; Jin, Suk-Won; Sun, Lele; Sun, Hongye; Kibbey, Richard G; Hirschi, Karen K; Hay, Nissim; Carmeliet, Peter; Chittenden, Thomas W; Eichmann, Anne; Potente, Michael; Simons, Michael

2017-05-11

Blood and lymphatic vasculatures are intimately involved in tissue oxygenation and fluid homeostasis maintenance. Assembly of these vascular networks involves sprouting, migration and proliferation of endothelial cells. Recent studies have suggested that changes in cellular metabolism are important to these processes. Although much is known about vascular endothelial growth factor (VEGF)-dependent regulation of vascular development and metabolism, little is understood about the role of fibroblast growth factors (FGFs) in this context. Here we identify FGF receptor (FGFR) signalling as a critical regulator of vascular development. This is achieved by FGF-dependent control of c-MYC (MYC) expression that, in turn, regulates expression of the glycolytic enzyme hexokinase 2 (HK2). A decrease in HK2 levels in the absence of FGF signalling inputs results in decreased glycolysis, leading to impaired endothelial cell proliferation and migration. Pan-endothelial- and lymphatic-specific Hk2 knockouts phenocopy blood and/or lymphatic vascular defects seen in Fgfr1/Fgfr3 double mutant mice, while HK2 overexpression partly rescues the defects caused by suppression of FGF signalling. Thus, FGF-dependent regulation of endothelial glycolysis is a pivotal process in developmental and adult vascular growth and development.

An immunohistochemical analysis of canine haemangioma and haemangiosarcoma.

PubMed

Sabattini, S; Bettini, G

2009-01-01

The aim of the present study was to investigate immunohistochemically aspects of the biology of canine endothelial neoplasia. Forty samples of canine cutaneous and visceral haemangiosarcoma (HSA), 29 samples of cutaneous and visceral haemangioma (HA) and 10 control samples of granulation tissue (GT) were labelled with antisera specific for vimentin, smooth muscle actin, von Willebrand factor (vWF), CD117 (KIT), vascular endothelial growth factor receptor-3 (VEGFR-3), vascular endothelial growth factor-C (VEGFC) and CD44. Further antisera were employed to determine the level of cellular proliferation (MIB-1 index) and toluidine blue staining was used to detect populations of tumour-infiltrating mast cells (MCs). There was greater expression of CD117, VEGFR-3 and CD44 in HSA than in HA, suggesting that these proteins might be suitable targets for the future development of novel therapeutic approaches to canine HSA. Marked infiltration of MC was detected in HA, suggesting a possible role for these cells in the pathogenesis of benign vascular neoplasia in the dog.

Endothelial transcription factor KLF2 negatively regulates liver regeneration via induction of activin A

PubMed Central

Manavski, Yosif; Abel, Tobias; Hu, Junhao; Kleinlützum, Dina; Buchholz, Christian J.; Belz, Christina; Augustin, Hellmut G.; Dimmeler, Stefanie

2017-01-01

Endothelial cells (ECs) not only are important for oxygen delivery but also act as a paracrine source for signals that determine the balance between tissue regeneration and fibrosis. Here we show that genetic inactivation of flow-induced transcription factor Krüppel-like factor 2 (KLF2) in ECs results in reduced liver damage and augmentation of hepatocyte proliferation after chronic liver injury by treatment with carbon tetrachloride (CCl4). Serum levels of GLDH3 and ALT were significantly reduced in CCl4-treated EC-specific KLF2-deficient mice. In contrast, transgenic overexpression of KLF2 in liver sinusoidal ECs reduced hepatocyte proliferation. KLF2 induced activin A expression and secretion from endothelial cells in vitro and in vivo, which inhibited hepatocyte proliferation. However, loss or gain of KLF2 expression did not change capillary density and liver fibrosis, but significantly affected hepatocyte proliferation. Taken together, the data demonstrate that KLF2 induces an antiproliferative secretome, including activin A, which attenuates liver regeneration. PMID:28348240

Uncaria rhynchophylla induces angiogenesis in vitro and in vivo.

PubMed

Choi, Do-Young; Huh, Jeong-Eun; Lee, Jae-Dong; Cho, Eun-Mi; Baek, Yong-Hyeon; Yang, Ha-Ru; Cho, Yoon-Je; Kim, Kang-Il; Kim, Deog-Yoon; Park, Dong-Suk

2005-12-01

Angiogenesis consists of the proliferation, migration, and differentiation of endothelial cells, and angiogenic factors and matrix protein interactions modulate this process. The aim of this study was to determine the angiogenic properties of Uncaria rhynchophylla. Uncaria rhynchophylla significantly enhanced human umbilical vein endothelial cells (HUVECs) proliferation in a dose-dependent manner. Neutralization of vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF) by monoclonal antibody suppressed the Uncaria rhynchophylla stimulatory effect on proliferation. In addition, Uncaria rhynchophylla significantly increased chemotactic-migration on gelatin and tubular structures on Matrigel of HUVECs in a dose-dependent manner. Interestingly, Uncaria rhynchophylla dose-dependently increased VEGF, and bFGF gene expression and protein secretion of HUVEC. The angiogenic activity of Uncaria rhynchophylla was confirmed using an in vivo Matrigel angiogenesis model, showing promotion of blood vessel formation. These results suggest that Uncaria rhynchophylla could potentially used to accelerate vascular wound healing or to promote the growth of collateral blood vessel in ischemic tissues.

Diabetes mellitus increases risk of unsuccessful graft preparation in Descemet membrane endothelial keratoplasty: a multicenter study.

PubMed

Greiner, Mark A; Rixen, Jordan J; Wagoner, Michael D; Schmidt, Gregory A; Stoeger, Christopher G; Straiko, Michael D; Zimmerman, M Bridget; Kitzmann, Anna S; Goins, Kenneth M

2014-11-01

The aim of this study was to evaluate preparation outcomes of tissue prepared for Descemet membrane endothelial keratoplasty (DMEK) from diabetic and nondiabetic donors. In this nonrandomized, consecutive case series, DMEK grafts were prepared from diabetic and nondiabetic donors by experienced technicians in 2 eye banks using slightly different, modified submerged manual preparation techniques to achieve "prestripped" graft tissue. Graft preparation results were analyzed retrospectively. The main outcome measure was the rate of unsuccessful (failed) DMEK graft preparations, defined as tears through the graft area that prevent tissue use. A total of 359 corneas prepared from 290 donors (114 diabetic and 245 nondiabetic) were included in the statistical analysis of graft preparation failure. There were no significant differences between diabetic and nondiabetic donor tissue characteristics with respect to donor age, death to preservation time, death to preparation time, endothelial cell density, percent hexagonality, or coefficient of variation. DMEK tissue preparation was unsuccessful in 19 (5.3%) cases. There was a significant difference in the site-adjusted rate of DMEK preparation failure between diabetic [15.3%; 95% confidence interval (CI), 9.0-25.0] and nondiabetic donors (1.9%; 95% CI, 0.8-4.8), and the corresponding site-adjusted odds ratio of DMEK graft preparation failure in diabetic donor tissue versus nondiabetic donor tissue was 9.20 (95% CI, 2.89-29.32; P = 0.001). Diabetes may be a risk factor for unsuccessful preparation of donor tissue for DMEK. We recommend caution in the use of diabetic tissue for DMEK graft preparation. Further study is needed to identify what subset of diabetic donors is at risk for unsuccessful DMEK graft preparation.

An emerging cell-based strategy in orthopaedics: endothelial progenitor cells.

PubMed

Atesok, Kivanc; Matsumoto, Tomoyuki; Karlsson, Jon; Asahara, Takayuki; Atala, Anthony; Doral, M Nedim; Verdonk, Rene; Li, Ru; Schemitsch, Emil

2012-07-01

The purpose of this article was to analyze the results of studies in the literature, which evaluated the use of endothelial progenitor cells (EPCs) as a cell-based tissue engineering strategy. EPCs have been successfully used in regenerative medicine to augment neovascularization in patients after myocardial infarction and limb ischemia. EPCs' important role as vasculogenic progenitors presents them as a potential source for cell-based therapies to promote bone healing. EPCs have been shown to have prominent effects in promoting bone regeneration in several animal models. Evidence indicates that EPCs promote bone regeneration by stimulating both angiogenesis and osteogenesis through a differentiation process toward endothelial cell lineage and formation of osteoblasts. Moreover, EPCs increase vascularization and osteogenesis by increased secretion of growth factors and cytokines through paracrine mechanisms. EPCs offer the potential to emerge as a new strategy among other cell-based therapies to promote bone regeneration. Further investigations and human trials are required to address current questions with regard to biology and mechanisms of action of EPCs in bone tissue engineering.

Proteomic analysis of corneal endothelial cell-descemet membrane tissues reveals influence of insulin dependence and disease severity in type 2 diabetes mellitus.

PubMed

Skeie, Jessica M; Aldrich, Benjamin T; Goldstein, Andrew S; Schmidt, Gregory A; Reed, Cynthia R; Greiner, Mark A

2018-01-01

The objective of this study was to characterize the proteome of the corneal endothelial cell layer and its basement membrane (Descemet membrane) in humans with various severities of type II diabetes mellitus compared to controls, and identify differentially expressed proteins across a range of diabetic disease severities that may influence corneal endothelial cell health. Endothelium-Descemet membrane complex tissues were peeled from transplant suitable donor corneas. Protein fractions were isolated from each sample and subjected to multidimensional liquid chromatography and tandem mass spectrometry. Peptide spectra were matched to the human proteome, assigned gene ontology, and grouped into protein signaling pathways unique to each of the disease states. We identified an average of 12,472 unique proteins in each of the endothelium-Descemet membrane complex tissue samples. There were 2,409 differentially expressed protein isoforms that included previously known risk factors for type II diabetes mellitus related to metabolic processes, oxidative stress, and inflammation. Gene ontology analysis demonstrated that diabetes progression has many protein footprints related to metabolic processes, binding, and catalysis. The most represented pathways involved in diabetes progression included mitochondrial dysfunction, cell-cell junction structure, and protein synthesis regulation. This proteomic dataset identifies novel corneal endothelial cell and Descemet membrane protein expression in various stages of diabetic disease. These findings give insight into the mechanisms involved in diabetes progression relevant to the corneal endothelium and its basement membrane, prioritize new pathways for therapeutic targeting, and provide insight into potential biomarkers for determining the health of this tissue.

In vitro differentiation of human tooth germ stem cells into endothelial- and epithelial-like cells.

PubMed

Doğan, Ayşegül; Demirci, Selami; Şahin, Fikrettin

2015-01-01

Current clinical techniques in dental practice include stem cell and tissue engineering applications. Dental stem cells are promising primary cell source for mainly tooth tissue engineering. Interaction of mesenchymal stem cell with epithelial and endothelial cells is strictly required for an intact tooth morphogenesis. Therefore, it is important to investigate whether human tooth germ stem cells (hTGSCs) derived from wisdom tooth are suitable for endothelial and epithelial cell transformation in dental tissue regeneration approaches. Differentiation into endothelial and epithelial cell lineages were mimicked under defined conditions, confirmed by real time PCR, western blotting and immunocytochemical analysis by qualitative and quantitative methods. HUVECs and HaCaT cells were used as positive controls for the endothelial and epithelial differentiation assays, respectively. Immunocytochemical and western blotting analysis revealed that terminally differentiated cells expressed cell-lineage markers including CD31, VEGFR2, VE-Cadherin, vWF (endothelial cell markers), and cytokeratin (CK)-17, CK-19, EpCaM, vimentin (epithelial cell markers) in significant levels with respect to undifferentiated control cells. Moreover, high expression levels of VEGFR1, VEGFR2, VEGF, CK-18, and CK-19 genes were detected in differentiated endothelial and epithelial-like cells. Endothelial-like cells derived from hTGSCs were cultured on Matrigel, tube-like structure formations were followed as an indication for functional endothelial differentiation. hTGSCs successfully differentiate into various cell types with a broad range of functional abilities using an in vitro approach. These findings suggest that hTGSCs may serve a potential stem cell source for tissue engineering and cell therapy of epithelial and endothelial tissue. © 2014 International Federation for Cell Biology.

Real space flight travel is associated with ultrastructural changes, cytoskeletal disruption and premature senescence of HUVEC.

PubMed

Kapitonova, M Y; Muid, S; Froemming, G R A; Yusoff, W N W; Othman, S; Ali, A M; Nawawi, H M

2012-12-01

Microgravity, hypergravity, vibration, ionizing radiation and temperature fluctuations are major factors of outer space flight affecting human organs and tissues. There are several reports on the effect of space flight on different human cell types of mesenchymal origin while information regarding changes to vascular endothelial cells is scarce. Ultrastructural and cytophysiological features of macrovascular endothelial cells in outer space flight and their persistence during subsequent culturing were demonstrated in the present investigation. At the end of the space flight, endothelial cells displayed profound changes indicating cytoskeletal lesions and increased cell membrane permeability. Readapted cells of subsequent passages exhibited persisting cytoskeletal changes, decreased metabolism and cell growth indicating cellular senescence.

Gene expression analysis of immunostained endothelial cells isolated from formaldehyde-fixated paraffin embedded tumors using laser capture microdissection--a technical report.

PubMed

Kaneko, Tomoatsu; Okiji, Takashi; Kaneko, Reika; Suda, Hideaki; Nör, Jacques E

2009-12-01

Laser capture microdissection (LCM) allows microscopic procurement of specific cell types from tissue sections that can then be used for gene expression analysis. In conventional LCM, frozen tissues stained with hematoxylin are normally used to the molecular analysis. Recent studies suggested that it is possible to carry out gene expression analysis of formaldehyde-fixated paraffin embedded (FFPE) tissues that were stained with hematoxylin. However, it is still unclear if quantitative gene expression analyses can be performed from LCM cells from FFPE tissues that were subjected to immunostaining to enhance identification of target cells. In this proof-of-principle study, we analyzed by reverse transcription-PCR (RT-PCR) and real time PCR the expression of genes in factor VIII immunostained human endothelial cells that were dissected from FFPE tissues by LCM. We observed that immunostaining should be performed at 4 degrees C to preserve the mRNA from the cells. The expression of Bcl-2 in the endothelial cells was evaluated by RT-PCR and by real time PCR. Glyceraldehyde-3-phosphate dehydrogenase and 18S were used as house keeping genes for RT-PCR and real time PCR, respectively. This report unveils a method for quantitative gene expression analysis in cells that were identified by immunostaining and retrieved by LCM from FFPE tissues. This method is ideally suited for the analysis of relatively rare cell types within a tissue, and should improve on our ability to perform differential diagnosis of pathologies as compared to conventional LCM.

Angiogenic properties of endometrial mesenchymal stromal cells in endothelial co-culture: an in vitro model of endometriosis.

PubMed

Canosa, S; Moggio, A; Brossa, A; Pittatore, G; Marchino, G L; Leoncini, S; Benedetto, C; Revelli, A; Bussolati, B

2017-03-01

Can endometrial mesenchymal stromal cells (E-MSCs) differentiate into endothelial cells in an in vitro co-culture system with human umbilical vein endothelial cells (HUVECs)? E-MSCs can acquire endothelial markers and function in a direct co-culture system with HUVECs. E-MSCs have been identified in the human endometrium as well as in endometriotic lesions. E-MSCs appear to be involved in formation of the endometrial stromal vascular tissue and the support of tissue growth and vascularization. The use of anti-angiogenic drugs appears as a possible therapeutic strategy against endometriosis. This is an in vitro study comprising patients receiving surgical treatment of ovarian endometriosis (n = 9). E-MSCs were isolated from eutopic and ectopic endometrial tissue and were characterized for the expression of mesenchymal and endothelial markers by FACS analysis and Real-Time PCR. CD31 acquisition was evaluated by FACS analysis and immunofluorescence after a 48 h-direct co-culture with green fluorescent protein +-HUVECs. A tube-forming assay was set up in order to analyze the functional potential of their interaction. Finally, co-cultures were treated with the anti-angiogenic agent Cabergoline. A subpopulation of E-MSCs acquired CD31 expression and integrated into tube-like structures when directly in contact with HUVECs, as observed by both FACS analysis and immunofluorescence. The isolation of CD31+ E-MSCs revealed significant increases in CD31, vascular endothelial growth factor receptor 2, TEK receptor tyrosine kinase and vascular endothelial-Cadherin mRNA expression levels with respect to basal and to CD31neg cells (P < 0.05). On the other hand, the expression of mesenchymal genes such as c-Myc, Vimentin, neuronal-Cadherin and sushi domain containing 2 remained unchanged. Cabergoline treatment induced a significant reduction of the E-MSC angiogenic potential (P < 0.05 versus control). Not applicable. Further studies are necessary to investigate the cellular and molecular mechanisms underlying the endothelial cell differentiation. E-MSCs may undergo endothelial differentiation, and be potentially involved in the development of endometriotic implants. Cell culture systems that more closely mimic the cellular complexity typical of endometriotic tissues in vivo are required to develop novel strategies for treatment. This study was supported by the 'Research Fund ex-60%', University of Turin, Turin, Italy. All authors declare that their participation in the study did not involve actual or potential conflicts of interests. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Comparative Biology of Decellularized Lung Matrix: Implications of Species Mismatch in Regenerative Medicine

PubMed Central

Balestrini, Jenna L.; Gard, Ashley L.; Gerhold, Kristin A.; Wilcox, Elise C.; Liu, Angela; Schwan, Jonas; Le, Andrew V.; Baevova, Pavlina; Dimitrievska, Sashka; Zhao, Liping; Sundaram, Sumati; Sun, Huanxing; Rittié, Laure; Dyal, Rachel; Broekelmann, Tom J.; Mecham, Robert P.; Schwartz, Martin A.; Niklason, Laura E.; White, Eric S.

2016-01-01

Lung engineering is a promising technology, relying on re-seeding of either human or xenographic decellularized matrices with patient-derived pulmonary cells. Little is known about the species-specificity of decellularization in various models of lung regeneration, or if species dependent cell-matrix interactions exist within these systems. Therefore decellularized scaffolds were produced from rat, pig, primate and human lungs, and assessed by measuring residual DNA, mechanical properties, and key matrix proteins (collagen, elastin, glycosaminoglycans). To study intrinsic matrix biologic cues, human endothelial cells were seeded onto acellular slices and analyzed for markers of cell health and inflammation. Despite similar levels of collagen after decellularization, human and primate lungs were stiffer, contained more elastin, and retained fewer glycosaminoglycans than pig or rat lung scaffolds. Human endothelial cells seeded onto human and primate lung tissue demonstrated less expression of vascular cell adhesion molecule and activation of nuclear factor-κB compared to those seeded onto rodent or porcine tissue. Adhesion of endothelial cells was markedly enhanced on human and primate tissues. Our work suggests that species-dependent biologic cues intrinsic to lung extracellular matrix could have profound effects on attempts at lung regeneration. PMID:27344365

Central Role of eNOS in the Maintenance of Endothelial Homeostasis

PubMed Central

Rodriguez-Mateos, Ana; Kelm, Malte

2015-01-01

Abstract Significance: Disruption of endothelial function is considered a key event in the development and progression of atherosclerosis. Endothelial nitric oxide synthase (eNOS) is a central regulator of cellular function that is important to maintain endothelial homeostasis. Recent Advances: Endothelial homeostasis encompasses acute responses such as adaption of flow to tissue's demand and more sustained responses to injury such as re-endothelialization and sprouting of endothelial cells (ECs) and attraction of circulating angiogenic cells (CAC), both of which support repair of damaged endothelium. The balance and the intensity of endothelial damage and repair might be reflected by changes in circulating endothelial microparticles (EMP) and CAC. Flow-mediated vasodilation (FMD) is a generally accepted clinical read-out of NO-dependent vasodilation, whereas EMP are upcoming prognostically validated markers of endothelial injury and CAC are reflective of the regenerative capacity with both expressing a functional eNOS. These markers can be integrated in a clinical endothelial phenotype, reflecting the net result between damage from risk factors and endogenous repair capacity with NO representing a central signaling molecule. Critical Issues: Improvements of reproducibility and observer independence of FMD measurements and definitions of relevant EMP and CAC subpopulations warrant further research. Future Directions: Endothelial homeostasis may be a clinical therapeutic target for cardiovascular health maintenance. Antioxid. Redox Signal. 22, 1230–1242. PMID:25330054

Decellularized skin/adipose tissue flap matrix for engineering vascularized composite soft tissue flaps.

PubMed

Zhang, Qixu; Johnson, Joshua A; Dunne, Lina W; Chen, Youbai; Iyyanki, Tejaswi; Wu, Yewen; Chang, Edward I; Branch-Brooks, Cynthia D; Robb, Geoffrey L; Butler, Charles E

2016-04-15

Using a perfusion decellularization protocol, we developed a decellularized skin/adipose tissue flap (DSAF) comprising extracellular matrix (ECM) and intact vasculature. Our DSAF had a dominant vascular pedicle, microcirculatory vascularity, and a sensory nerve network and retained three-dimensional (3D) nanofibrous structures well. DSAF, which was composed of collagen and laminin with well-preserved growth factors (e.g., vascular endothelial growth factor, basic fibroblast growth factor), was successfully repopulated with human adipose-derived stem cells (hASCs) and human umbilical vein endothelial cells (HUVECs), which integrated with DSAF and formed 3D aggregates and vessel-like structures in vitro. We used microsurgery techniques to re-anastomose the recellularized DSAF into nude rats. In vivo, the engineered flap construct underwent neovascularization and constructive remodeling, which was characterized by the predominant infiltration of M2 macrophages and significant adipose tissue formation at 3months postoperatively. Our results indicate that DSAF co-cultured with hASCs and HUVECs is a promising platform for vascularized soft tissue flap engineering. This platform is not limited by the flap size, as the entire construct can be immediately perfused by the recellularized vascular network following simple re-integration into the host using conventional microsurgical techniques. Significant soft tissue loss resulting from traumatic injury or tumor resection often requires surgical reconstruction using autologous soft tissue flaps. However, the limited availability of qualitative autologous flaps as well as the donor site morbidity significantly limits this approach. Engineered soft tissue flap grafts may offer a clinically relevant alternative to the autologous flap tissue. In this study, we engineered vascularized soft tissue free flap by using skin/adipose flap extracellular matrix scaffold (DSAF) in combination with multiple types of human cells. Following vascular reanastomosis in the recipient site, the engineered products successful regenerated large-scale fat tissue in vivo. This approach may provide a translatable platform for composite soft tissue free flap engineering for microsurgical reconstruction. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Collagen-binding vascular endothelial growth factor attenuates CCl4-induced liver fibrosis in mice

PubMed Central

Wu, Kangkang; Huang, Rui; Wu, Hongyan; Liu, Yong; Yang, Chenchen; Cao, Shufeng; Hou, Xianglin; Chen, Bing; Dai, Jianwu; Wu, Chao

2016-01-01

Vascular endothelial growth factor (VEGF) serves an important role in promoting angiogenesis and tissue regeneration. However, the lack of an effective delivery system that can target this growth factor to the injured site reduces its therapeutic efficacy. Therefore, in the current study, collagen-binding VEGF was constructed by fusing a collagen-binding domain (CBD) to the N-terminal of native VEGF. The CBD-VEGF can specifically bind to collagen which is the major component of the extracellular matrix in fibrotic liver. The anti-fibrotic effects of this novel material were investigated by the carbon tetrachloride (CCl4)-induced liver fibrotic mouse model. Mice were injected with CCl4 intraperitoneally to induce liver fibrosis. CBD-VEGF was injected directly into the liver tissue of mice. The liver tissues were stained with hematoxylin and eosin for general observation or with Masson's trichrome staining for detection of collagen deposition. The hepatic stellate cell activation, blood vessel formation and hepatocyte proliferation were measured by immunohistochemical staining for α-smooth muscle actin, CD31 and Ki67 in the liver tissue. The fluorescent TUNEL assay was performed to evaluate the hepatocyte apoptosis. The present study identified that the CBD-VEGF injection could significantly promote vascularization of the liver tissue of fibrotic mice and attenuate liver fibrosis. Furthermore, hepatocyte apoptosis and hepatic stellate cell activation were attenuated by CBD-VEGF treatment. CBD-VEGF treatment could additionally promote hepatocyte regeneration in the liver tissue of fibrotic mice. Thus, it was suggested that CBD-VEGF may be used as a novel therapeutic intervention for liver fibrosis. PMID:27748931

Angiogenin distribution in human term placenta, and expression by cultured trophoblastic cells

PubMed Central

Pavlov, Nadine; Hatzi, Elissavet; Bassaglia, Yann; Frendo, Jean-Louis; Evain-Brion, Danièle; Badet, Josette

2003-01-01

Human angiogenin is a 14-kDa secreted protein with angiogenic and ribonucleolytic activities. Angiogenin is associated with tumour development but is also present in normal biological fluids and tissues. To further address the physiological role of angiogenin, we studied its expression in situ and in vitro, using the human term placenta as a model of physiological angiogenesis. Angiogenin was immunodetected by light and transmission electron microscopy, and its cellular distribution was established by double immunolabelling with cell markers including von Willebrand factor, platelet/endothelial cell adhesion molecule-1 (PECAM-1), CD34, Tie-2, vascular endothelial cadherin (VE-cadherin), vascular endothelial growth factor receptor-2 (VEGF-R2), erythropoeitin receptor (Epo-R), alpha-smooth muscle actin, CD45, cytokeratin 7, and Ki-67. Angiogenin immunoreactivity was detected in villous and extravillous trophoblasts, the trophoblast basement membrane, the endothelial basal lamina, foetal blood vessels, foetal and maternal red blood cells, and amnionic cells. Its expression was confirmed by in situ hybridisation with a digoxygenin-labelled cDNA probe and reverse transcriptase-polymerase chain reaction amplification. Villous cytotrophoblasts, isolated and differentiated in vitro into a functional syncytiotrophoblast, expressed and secreted angiogenin. Given its known biological activities in vitro and its observed pattern of expression, these data suggest that, in human placenta, angiogenin has a role not only in angiogenesis but also in vascular and tissue homeostasis, maternal immune tolerance of the foetus, and host defences. PMID:15166501

Systemic Hypoxia Changes the Organ-Specific Distribution of Vascular Endothelial Growth Factor and Its Receptors

NASA Astrophysics Data System (ADS)

Marti, Hugo H.; Risau, Werner

1998-12-01

Vascular endothelial growth factor (VEGF) plays a key role in physiological blood vessel formation and pathological angiogenesis such as tumor growth and ischemic diseases. Hypoxia is a potent inducer of VEGF in vitro. Here we demonstrate that VEGF is induced in vivo by exposing mice to systemic hypoxia. VEGF induction was highest in brain, but also occurred in kidney, testis, lung, heart, and liver. In situ hybridization analysis revealed that a distinct subset of cells within a given organ, such as glial cells and neurons in brain, tubular cells in kidney, and Sertoli cells in testis, responded to the hypoxic stimulus with an increase in VEGF expression. Surprisingly, however, other cells at sites of constitutive VEGF expression in normal adult tissues, such as epithelial cells in the choroid plexus and kidney glomeruli, decreased VEGF expression in response to the hypoxic stimulus. Furthermore, in addition to VEGF itself, expression of VEGF receptor-1 (VEGFR-1), but not VEGFR-2, was induced by hypoxia in endothelial cells of lung, heart, brain, kidney, and liver. VEGF itself was never found to be up-regulated in endothelial cells under hypoxic conditions, consistent with its paracrine action during normoxia. Our results show that the response to hypoxia in vivo is differentially regulated at the level of specific cell types or layers in certain organs. In these tissues, up- or down-regulation of VEGF and VEGFR-1 during hypoxia may influence their oxygenation after angiogenesis or modulate vascular permeability.

Exosomes of human placenta-derived mesenchymal stem cells stimulate angiogenesis.

PubMed

Komaki, Motohiro; Numata, Yuri; Morioka, Chikako; Honda, Izumi; Tooi, Masayuki; Yokoyama, Naoki; Ayame, Hirohito; Iwasaki, Kengo; Taki, Atsuko; Oshima, Noriko; Morita, Ikuo

2017-10-03

The therapeutic potential of mesenchymal stem cells (MSCs) may be attributed partly to humoral factors such as growth factors, cytokines, and chemokines. Human term placental tissue-derived MSCs (PlaMSCs), or conditioned medium left over from cultures of these cells, have been reported to enhance angiogenesis. Recently, the exosome, which can transport a diverse suite of macromolecules, has gained attention as a novel intercellular communication tool. However, the potential role of the exosome in PlaMSC therapeutic action is not well understood. The purpose of this study was to evaluate PlaMSC-derived exosome angiogenesis promotion in vitro and in vivo. MSCs were isolated from human term placental tissue by enzymatic digestion. Conditioned medium was collected after 48-h incubation in serum-free medium (PlaMSC-CM). Angiogenic factors present in PlaMSC-CM were screened by a growth factor array. Exosomes were prepared by ultracentrifugation of PlaMSC-CM, and confirmed by transmission electron microscopy, dynamic light scattering, and western blot analyses. The proangiogenic activity of PlaMSC-derived exosomes (PlaMSC-exo) was assessed using an endothelial tube formation assay, a cell migration assay, and reverse transcription-PCR analysis. The in-vivo angiogenic activity of PlaMSC-exo was evaluated using a murine auricle ischemic injury model. PlaMSC-CM contained both angiogenic and angiostatic factors, which enhanced endothelial tube formation. PlaMSC-exo were incorporated into endothelial cells; these exosomes stimulated both endothelial tube formation and migration, and enhanced angiogenesis-related gene expression. Laser Doppler blood flow analysis showed that PlaMSC-exo infusion also enhanced angiogenesis in an in-vivo murine auricle ischemic injury model. PlaMSC-exo enhanced angiogenesis in vitro and in vivo, suggesting that exosomes play a role in the proangiogenic activity of PlaMSCs. PlaMSC-exo may be a novel therapeutic approach for treating ischemic diseases.

Topical Administration of Oxygenated Hemoglobin Improved Wound Healing in an Ischemic Rabbit Ear Model.

PubMed

Xie, Ping; Jia, Shengxian; Tye, Ross; Xu, Wei; Zhong, Aimei; Hong, Seok J; Galiano, Robert D; Mustoe, Thomas A

2016-02-01

Localized oxygen deficiency plays a central role in the pathogenesis of chronic wounds; thus, rectifying localized ischemia with oxygen therapy has been postulated to be an integral aspect of the management of chronic wounds. The efficacy of a novel approach for oxygen therapy on chronic wound healing was evaluated. Oxygen was delivered to ischemic wounds by means of the topical application of oxygenated, chemically modified bovine hemoglobin (IKOR 2084) in a validated rabbit ear ischemic wound model. The wound healing was evaluated histologically by measuring epithelial gap and neo-granulation tissue area. In situ expression of endothelial cells (CD31) and proliferative cells (Ki-67) was examined by immunohistochemistry analysis. The mRNA of vascular endothelial growth factor, endothelial nitric oxide synthase, and matrix metalloproteinase-9 was quantified by real-time reverse-transcriptase polymerase chain reaction. The collagen was detected by Sirius red staining. In comparison with topical application of saline, the administration of oxygenated IKOR 2084 increases wound reepithelialization and formation of neo-granulation tissue in a dose-dependent manner, and cellular proliferation (Ki-67). Conversely, the administration of deoxygenated IKOR 2084 aggravated the ischemic wound healing process. Moreover, the topical administration of oxygenated IKOR 2084 induces angiogenesis as evidenced by concomitant increases in CD31 protein and vascular endothelial growth factor and endothelial nitric oxide synthase mRNA expression in treated wounds. Oxygenated IKOR 2084 administration also increased collagen deposition in wounds, with decreases in the expression of matrix metalloproteinase-9 mRNA. This study suggests that the topical application of oxygenated IKOR 2084 ameliorates the reparative progress of ischemic wounds through enhanced angiogenesis, cellular proliferation, and collagen deposition.

Vascular endothelial growth factor and soft tissue sarcomas: tumor expression correlates with grade.

PubMed

Chao, C; Al-Saleem, T; Brooks, J J; Rogatko, A; Kraybill, W G; Eisenberg, B

2001-04-01

Vascular endothelial growth factor (VEGF), an endothelial-specific mitogen overexpressed in various epithelial malignancies is thought to be a potent regulator of angiogenesis. We hypothesized that some soft tissue sarcomas, due to their high propensity for hematogenous metastases (1) would overexpress VEGF, (2) that the degree of expression may represent a significant biologic predictor for disease-specific survival, and (3) that recurrent tumor would express as high or higher VEGF compared with the primary tumor. Selected paraffin-embedded tissue of surgical specimens from 79 patients with soft tissue sarcomas, treated between 1989 and 1995 were stained with a rabbit polyclonal anti-VEGF antibody at a concentration of 2 microg/ml. Slides were assessed for VEGF expression as high or low by two investigators blinded to the clinicopathologic data. Twelve patients had VEGF expression of their primary tumors, and their recurrent tumors were compared. The Fishers' exact test assessed for differences in VEGF expression; survival analyses were performed according to the methods of Kaplan and Meier. Seventy-eight percent (29 of 37) of patients who died of disease had high VEGF expression. However, VEGF expression was not an independent predictor of either overall or disease-free survival. Tumor grade correlated with VEGF expression significantly. For the low-grade tumors, 7 of 13 expressed low VEGF, whereas for high-grade tumors, 53 of 66 expressed high VEGF (P = .016). Seven of the 12 paired tumor samples expressed identical VEGF immunostaining. The majority of high-grade soft tissue sarcomas in this study have high intensity VEGF expression. This finding may provide useful information on individual soft tissue sarcomas and offer the basis for therapeutic and biologic targeting in high-risk patients using anti-angiogenesis strategies. However, in our analysis, after accounting for tumor grade, VEGF does not seem to be an independent predictor of clinical outcome.

Therapeutic Angiogenesis via Solar Cell-Facilitated Electrical Stimulation.

PubMed

Jeong, Gun-Jae; Oh, Jin Young; Kim, Yeon-Ju; Bhang, Suk Ho; Jang, Hyeon-Ki; Han, Jin; Yoon, Jeong-Kee; Kwon, Sang-Mo; Lee, Tae Il; Kim, Byung-Soo

2017-11-08

Cell therapy has been suggested as a treatment modality for ischemic diseases, but the poor survival and engraftment of implanted cells limit its therapeutic efficacy. To overcome such limitation, we used electrical stimulation (ES) derived from a wearable solar cell for inducing angiogenesis in ischemic tissue. ES enhanced the secretion of angiogenic growth factors and the migration of mesenchymal stem cells (MSCs), myoblasts, endothelial progenitor cells, and endothelial cells in vitro. In a mouse ischemic hindlimb model, ES generated by a solar cell and applied to the ischemic region promoted migration of MSCs toward the ischemic site and upregulated expression of angiogenic paracrine factors (vascular endothelial, basic fibroblast, and hepatocyte growth factors; and stromal cell-derived factor-1α). Importantly, solar cell-generated ES promoted the formation of capillaries and arterioles at the ischemic region, attenuated muscle necrosis and fibrosis, and eventually prevented loss of the ischemic limb. Solar cell ES therapy showed higher angiogenic efficacy than conventional MSC therapy. This study shows the feasibility of using solar cell ES as a novel treatment for therapeutic angiogenesis.

Predictive model of thrombospondin-1 and vascular endothelial growth factor in breast tumor tissue.

PubMed

Rohrs, Jennifer A; Sulistio, Christopher D; Finley, Stacey D

2016-01-01

Angiogenesis, the formation of new blood capillaries from pre-existing vessels, is a hallmark of cancer. Thus far, strategies for reducing tumor angiogenesis have focused on inhibiting pro-angiogenic factors, while less is known about the therapeutic effects of mimicking the actions of angiogenesis inhibitors. Thrombospondin-1 (TSP1) is an important endogenous inhibitor of angiogenesis that has been investigated as an anti-angiogenic agent. TSP1 impedes the growth of new blood vessels in many ways, including crosstalk with pro-angiogenic factors. Due to the complexity of TSP1 signaling, a predictive systems biology model would provide quantitative understanding of the angiogenic balance in tumor tissue. Therefore, we have developed a molecular-detailed, mechanistic model of TSP1 and vascular endothelial growth factor (VEGF), a promoter of angiogenesis, in breast tumor tissue. The model predicts the distribution of the angiogenic factors in tumor tissue, revealing that TSP1 is primarily in an inactive, cleaved form due to the action of proteases, rather than bound to its cellular receptors or to VEGF. The model also predicts the effects of enhancing TSP1's interactions with its receptors and with VEGF. To provide additional predictions that can guide the development of new anti-angiogenic drugs, we simulate administration of exogenous TSP1 mimetics that bind specific targets. The model predicts that the CD47-binding TSP1 mimetic dramatically decreases the ratio of receptor-bound VEGF to receptor-bound TSP1, in favor of anti-angiogenesis. Thus, we have established a model that provides a quantitative framework to study the response to TSP1 mimetics.

Hypoxia-Inducible Factor-1α (HIF-1α) Expression on Endothelial Cells in Juvenile Nasopharyngeal Angiofibroma: A Review of 70 cases and Tissue Microarray Analysis.

PubMed

Song, Xiaole; Yang, Chenhe; Zhang, Huankang; Wang, Jingjing; Sun, Xicai; Hu, Li; Liu, Zhuofu; Wang, Dehui

2018-06-01

To examine the expression of hypoxia-inducible factor-1α (HIF-1α) and its related molecules (cellular repressor of E1A-stimulated genes [CREG], osteopontin [OPN], proto-oncogene tyrosine-protein kinase Src [c-Src], and vascular endothelial growth factor [VEGF]) in juvenile nasopharyngeal angiofibroma (JNA) and explore the correlation between clinical prognosis and HIF-1α expression. The study performed a retrospective review of the clinical records of patients with JNA treated between 2003 and 2007. Specimens were analyzed by immunohistochemistry for HIF-1α, CREG, OPN, c-Src, and VEGF expression, and microvessel density (MVD) was assessed by tissue microarray. The correlation between expression levels and clinicopathological features including age, tumor stage, intraoperative blood loss, and recurrence was analyzed. HIF-1α, CREG, OPN, c-Src, and VEGF were upregulated in endothelial cells (ECs) of patients with JNA, and strong correlations in the expression of these molecules were observed. HIF-1α expression was higher in young patients ( P = .032) and in recurrent cases ( P = .01). Survival analysis showed that low HIF-1α levels in ECs predicted longer time to recurrence (log rank test P = .006). Receiver operating characteristic curve analysis showed that HIF-1α was a prognostic factor for recurrence (area under the curve = 0.690, P = .019). No correlation was found between the expression of molecules and Radkowski stage or intraoperative blood loss. In cases of JNA treated surgically, HIF-1α expression in ECs is a useful prognostic factor for tumor recurrence.

Outcomes of Spatially Fractionated Radiotherapy (GRID) for Bulky Soft Tissue Sarcomas in a Large Animal Model

PubMed Central

Gieger, Tracy L.; Karakashian, Alexander A.; Nikolova-Karakashian, Mariana N.; Posner, Lysa P.; Roback, Donald M.; Rivera, Judith N.; Chang, Sha

2017-01-01

GRID directs alternating regions of high- and low-dose radiation at tumors. A large animal model mimicking the geometries of human treatments is needed to complement existing rodent systems (eg, microbeam) and clarify the physical and biological attributes of GRID. A pilot study was undertaken in pet dogs with spontaneous soft tissue sarcomas to characterize responses to GRID. Subjects were treated with either 20 Gy (3 dogs) or 25 Gy (3 dogs), delivered using 6 MV X-rays and a commercial GRID collimator. Acute toxicity and tumor responses were assessed 2, 4, and 6 weeks later. Acute Radiation Therapy Oncology Group grade I skin toxicity was observed in 3 of the 6 dogs; none experienced a measurable response, per Response Evaluation Criteria in Solid Tumors. Serum vascular endothelial growth factor, tumor necrosis factor α, and secretory sphingomyelinase were assayed at baseline, 1, 4, 24, and 48 hours after treatment. There was a trend toward platelet-corrected serum vascular endothelial growth factor concentration being lower 1 and 48 hours after GRID than at baseline. There was a significant decrease in secretory sphingomyelinase activity 48 hours after 25 Gy GRID (P = .03). Serum tumor necrosis factor α was quantified measurable at baseline in 4 of the 6 dogs and decreased in each of those subjects at all post-GRID time points. The new information generated by this study includes the observation that high-dose, single fraction application of GRID does not induce measurable reduction in volume of canine soft tissue sarcomas. In contrast to previously published data, these data suggest that GRID may be associated with at least short-term reduction in serum concentration of vascular endothelial growth factor and serum activity of secretory sphingomyelinase. Because GRID can be applied safely, and these tumors can be subsequently surgically resected as part of routine veterinary care, pet dogs with sarcomas are an appealing model for studying the radiobiologic responses to spatially fractionated radiotherapy. PMID:28168937

Nonselective inhibition of prostaglandin-endoperoxide synthase by naproxen ameliorates hepatic injury in animals with acute or chronic liver injury

PubMed Central

Bahde, Ralf; Kapoor, Sorabh; Gupta, Sanjeev

2014-01-01

The rising prevalence of hepatic injury due to toxins, metabolites, viruses, etc., necessitates development of further mechanisms for protecting the liver and for treating acute or chronic liver diseases. To examine whether inhibition of inflammation directed by cyclo-oxygenase pathways, we performed animal studies with naproxen, which inhibits prostaglandin-endoperoxide synthases 1 and 2 and is in extensive clinical use. We administered carbon tetrachloride to induce acute liver injury and ligated the common bile duct to induce chronic liver injury in adult rats. These experimental manipulations produced abnormalities in liver tests, tissue necrosis, compensatory hepatocyte or biliary proliferation, and onset of fibrosis, particularly after bile duct ligation. After carbon tetrachloride-induced acute injury, naproxen decreased liver test abnormalities, tissue necrosis and compensatory hepatocellular proliferation. After bile duct ligation-induced chronic injury, naproxen decreased liver test abnormalities, tissue injury and compensatory biliary hyperplasia. Moreover, after bile duct ligation, naproxen-treated rats showed more periductular oval liver cells, which have been classified as hepatic progenitor cells. In naproxen-treated rats, we found greater expression in hepatic stellate cells and mononuclear cells of cytoprotective factors, such as vascular endothelial growth factor. The ability of naproxen to induce expression of vascular endothelial growth factor was verified in cell culture studies with CFSC-8B clone of rat hepatic stellate cells. Whereas assays for carbon tetrachloride toxicity using cultured primary hepatocytes established that naproxen was not directly cytoprotective, we found conditioned medium containing vascular endothelial growth factor from naproxen-treated CFSC-8B cells protected hepatocytes from carbon tetrachloride toxicity. Therefore, naproxen was capable of ameliorating toxic liver injury, which involved naproxen-induced release of physiological cytoprotective factors in nonparenchymal liver cells. Such drug-induced release of endogenous cytoprotectants will advance therapeutic development for hepatic injury. PMID:24220607

UPREGULATION OF TISSUE FACTOR IN HUMAN ENDOTHELIAL CELLS FOLLOWING ULTRAFINE PARTICLE EXPOSURE

EPA Science Inventory

Epidemiology studies have linked the exposure to air pollutant particles with increased cardiovascular mortality and morbidity, but the mechanisms remain unknown. In our laboratory we have tested the hypothesis that the ultrafine fraction of ambient pollutant particles would cau...

Microparticles released by vascular endothelial cells increase hypoxia inducible factor expression in human proximal tubular HK-2 cells.

PubMed

Fernandez-Martínez, Ana Belen; Torija, Ana Valdehita; Carracedo, Julia; Ramirez, Rafael; de Lucio-Cazaña, Francisco Javier

2014-08-01

Microparticles are produced by vesiculation of the cell plasma membrane and serve as vectors of cell-to-cell communication. Co-culture experiments have shown that hypoxia-inducible factor-α (HIF-α)-regulated-genes are up-regulated in human renal proximal tubular HK-2 cells by endothelial cell factors which might be transported inside endothelial microparticles (EMP). Here we aimed to study in HK-2 cells the effect of EMP, produced by activated endothelial cells, on HIF-α and HIF-α-regulated vascular endothelial growth factor-A (VEGF-A). EMP, at a concentration much lower than that found in plasma, increased the expression of HIF-α/VEGF-A in a COX-2/EP2 receptor dependent manner. Since the EMP/cells ratio was ∼1/1000, we hypothesized that paracrine mediators produced by HK-2 cells amplified the initial signal. This hypothesis was confirmed by two facts which also suggested that the mediators were conveyed by particles released by HK-2 cells: (i) HIF-α was up-regulated in HK-2 cells treated with the pellet obtained from the conditioned medium of the EMP-treated HK-2 cells. (ii) In transwell experiments, EMP-treated cells increased the expression of HIF-α in untreated HK-2 cells. Interestingly, we detected these cells, particles that were released by EMP-treated HK-2 cells. Depending on the pathological context, activation of HIF-α and VEGF-A signaling in renal tissue/cells may have either beneficial or harmful effects. Therefore, our results suggest that their presence in the urinary space of EMP produced by activated endothelial cells may influence the outcome of a number of renal diseases. Copyright © 2014 Elsevier Ltd. All rights reserved.

A systems biology approach identified different regulatory networks targeted by KSHV miR-K12-11 in B cells and endothelial cells.

PubMed

Yang, Yajie; Boss, Isaac W; McIntyre, Lauren M; Renne, Rolf

2014-08-08

Kaposi's sarcoma associated herpes virus (KSHV) is associated with tumors of endothelial and lymphoid origin. During latent infection, KSHV expresses miR-K12-11, an ortholog of the human tumor gene hsa-miR-155. Both gene products are microRNAs (miRNAs), which are important post-transcriptional regulators that contribute to tissue specific gene expression. Advances in target identification technologies and molecular interaction databases have allowed a systems biology approach to unravel the gene regulatory networks (GRNs) triggered by miR-K12-11 in endothelial and lymphoid cells. Understanding the tissue specific function of miR-K12-11 will help to elucidate underlying mechanisms of KSHV pathogenesis. Ectopic expression of miR-K12-11 differentially affected gene expression in BJAB cells of lymphoid origin and TIVE cells of endothelial origin. Direct miRNA targeting accounted for a small fraction of the observed transcriptome changes: only 29 genes were identified as putative direct targets of miR-K12-11 in both cell types. However, a number of commonly affected biological pathways, such as carbohydrate metabolism and interferon response related signaling, were revealed by gene ontology analysis. Integration of transcriptome profiling, bioinformatic algorithms, and databases of protein-protein interactome from the ENCODE project identified different nodes of GRNs utilized by miR-K12-11 in a tissue-specific fashion. These effector genes, including cancer associated transcription factors and signaling proteins, amplified the regulatory potential of a single miRNA, from a small set of putative direct targets to a larger set of genes. This is the first comparative analysis of miRNA-K12-11's effects in endothelial and B cells, from tissues infected with KSHV in vivo. MiR-K12-11 was able to broadly modulate gene expression in both cell types. Using a systems biology approach, we inferred that miR-K12-11 establishes its GRN by both repressing master TFs and influencing signaling pathways, to counter the host anti-viral response and to promote proliferation and survival of infected cells. The targeted GRNs are more reproducible and informative than target gene identification, and our approach can be applied to other regulatory factors of interest.

Kaposi's Sarcoma Associated Herpes Virus (KSHV) Induced COX-2: A Key Factor in Latency, Inflammation, Angiogenesis, Cell Survival and Invasion

PubMed Central

Sharma-Walia, Neelam; Sadagopan, Sathish; Veettil, Mohanan Valiya; Kerur, Nagaraj; Chandran, Bala

2010-01-01

Kaposi's sarcoma (KS), an enigmatic endothelial cell vascular neoplasm, is characterized by the proliferation of spindle shaped endothelial cells, inflammatory cytokines (ICs), growth factors (GFs) and angiogenic factors. KSHV is etiologically linked to KS and expresses its latent genes in KS lesion endothelial cells. Primary infection of human micro vascular endothelial cells (HMVEC-d) results in the establishment of latent infection and reprogramming of host genes, and cyclooxygenase-2 (COX-2) is one of the highly up-regulated genes. Our previous study suggested a role for COX-2 in the establishment and maintenance of KSHV latency. Here, we examined the role of COX-2 in the induction of ICs, GFs, angiogenesis and invasive events occurring during KSHV de novo infection of endothelial cells. A significant amount of COX-2 was detected in KS tissue sections. Telomerase-immortalized human umbilical vein endothelial cells supporting KSHV stable latency (TIVE-LTC) expressed elevated levels of functional COX-2 and microsomal PGE2 synthase (m-PGES), and secreted the predominant eicosanoid inflammatory metabolite PGE2. Infected HMVEC-d and TIVE-LTC cells secreted a variety of ICs, GFs, angiogenic factors and matrix metalloproteinases (MMPs), which were significantly abrogated by COX-2 inhibition either by chemical inhibitors or by siRNA. The ability of these factors to induce tube formation of uninfected endothelial cells was also inhibited. PGE2, secreted early during KSHV infection, profoundly increased the adhesion of uninfected endothelial cells to fibronectin by activating the small G protein Rac1. COX-2 inhibition considerably reduced KSHV latent ORF73 gene expression and survival of TIVE-LTC cells. Collectively, these studies underscore the pivotal role of KSHV induced COX-2/PGE2 in creating KS lesion like microenvironment during de novo infection. Since COX-2 plays multiple roles in KSHV latent gene expression, which themselves are powerful mediators of cytokine induction, anti-apoptosis, cell survival and viral genome maintainence, effective inhibition of COX-2 via well-characterized clinically approved COX-2 inhibitors could potentially be used in treatment to control latent KSHV infection and ameliorate KS. PMID:20169190

Particulate matter induces prothrombotic microparticle shedding by human mononuclear and endothelial cells.

PubMed

Neri, Tommaso; Pergoli, Laura; Petrini, Silvia; Gravendonk, Lotte; Balia, Cristina; Scalise, Valentina; Amoruso, Angela; Pedrinelli, Roberto; Paggiaro, Pierluigi; Bollati, Valentina; Celi, Alessandro

2016-04-01

Particulate airborne pollution is associated with increased cardiopulmonary morbidity. Microparticles are extracellular vesicles shed by cells upon activation or apoptosis involved in physiological processes such as coagulation and inflammation, including airway inflammation. We investigated the hypothesis that particulate matter causes the shedding of microparticles by human mononuclear and endothelial cells. Cells, isolated from the blood and the umbilical cords of normal donors, were cultured in the presence of particulate from a standard reference. Microparticles were assessed in the supernatant as phosphatidylserine concentration. Microparticle-associated tissue factor was assessed by an one-stage clotting assay. Nanosight technology was used to evaluate microparticle size distribution. Particulate matter induces a dose- and time- dependent, rapid (1h) increase in microparticle generation in both cells. These microparticles express functional tissue factor. Particulate matter increases intracellular calcium concentration and phospholipase C inhibition reduces microparticle generation. Nanosight analysis confirmed that upon exposure to particulate matter both cells express particles with a size range consistent with the definition of microparticles (50-1000 nm). Exposure of mononuclear and endothelial cells to particulate matter upregulates the generation of microparticles at least partially mediated by calcium mobilization. This observation might provide a further link between airborne pollution and cardiopulmonary morbidity. Copyright © 2016 Elsevier B.V. All rights reserved.

Acemannan sponges stimulate alveolar bone, cementum and periodontal ligament regeneration in a canine class II furcation defect model.

PubMed

Chantarawaratit, P; Sangvanich, P; Banlunara, W; Soontornvipart, K; Thunyakitpisal, P

2014-04-01

Periodontal disease is a common infectious disease, found worldwide, causing the destruction of the periodontium. The periodontium is a complex structure composed of both soft and hard tissues, thus an agent applied to regenerate the periodontium must be able to stimulate periodontal ligament, cementum and alveolar bone regeneration. Recent studies demonstrated that acemannan, a polysaccharide extracted from Aloe vera gel, stimulated both soft and hard tissue healing. This study investigated effect of acemannan as a bioactive molecule and scaffold for periodontal tissue regeneration. Primary human periodontal ligament cells were treated with acemannan in vitro. New DNA synthesis, expression of growth/differentiation factor 5 and runt-related transcription factor 2, expression of vascular endothelial growth factor, bone morphogenetic protein-2 and type I collagen, alkaline phosphatase activity, and mineralized nodule formation were determined using [(3)H]-thymidine incorporation, reverse transcription-polymerase chain reaction, enzyme-linked immunoabsorbent assay, biochemical assay and alizarin red staining, respectively. In our in vivo study, premolar class II furcation defects were made in four mongrel dogs. Acemannan sponges were applied into the defects. Untreated defects were used as a negative control group. The amount of new bone, cementum and periodontal ligament formation were evaluated 30 and 60 d after the operation. Acemannan significantly increased periodontal ligament cell proliferation, upregulation of growth/differentiation factor 5, runt-related transcription factor 2, vascular endothelial growth factor, bone morphogenetic protein 2, type I collagen and alkaline phosphatase activity, and mineral deposition as compared with the untreated control group in vitro. Moreover, acemannan significantly accelerated new alveolar bone, cementum and periodontal ligament formation in class II furcation defects. Our data suggest that acemannan could be a candidate biomolecule for periodontal tissue regeneration. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Corneal donor tissue preparation for endothelial keratoplasty.

PubMed

Woodward, Maria A; Titus, Michael; Mavin, Kyle; Shtein, Roni M

2012-06-12

Over the past ten years, corneal transplantation surgical techniques have undergone revolutionary changes. Since its inception, traditional full thickness corneal transplantation has been the treatment to restore sight in those limited by corneal disease. Some disadvantages to this approach include a high degree of post-operative astigmatism, lack of predictable refractive outcome, and disturbance to the ocular surface. The development of Descemet's stripping endothelial keratoplasty (DSEK), transplanting only the posterior corneal stroma, Descemet's membrane, and endothelium, has dramatically changed treatment of corneal endothelial disease. DSEK is performed through a smaller incision; this technique avoids 'open sky' surgery with its risk of hemorrhage or expulsion, decreases the incidence of postoperative wound dehiscence, reduces unpredictable refractive outcomes, and may decrease the rate of transplant rejection. Initially, cornea donor posterior lamellar dissection for DSEK was performed manually resulting in variable graft thickness and damage to the delicate corneal endothelial tissue during tissue processing. Automated lamellar dissection (Descemet's stripping automated endothelial keratoplasty, DSAEK) was developed to address these issues. Automated dissection utilizes the same technology as LASIK corneal flap creation with a mechanical microkeratome blade that helps to create uniform and thin tissue grafts for DSAEK surgery with minimal corneal endothelial cell loss in tissue processing. Eye banks have been providing full thickness corneas for surgical transplantation for many years. In 2006, eye banks began to develop methodologies for supplying precut corneal tissue for endothelial keratoplasty. With the input of corneal surgeons, eye banks have developed thorough protocols to safely and effectively prepare posterior lamellar tissue for DSAEK surgery. This can be performed preoperatively at the eye bank. Research shows no significant difference in terms of the quality of the tissue or patient outcomes using eye bank precut tissue versus surgeon-prepared tissue for DSAEK surgery. For most corneal surgeons, the availability of precut DSAEK corneal tissue saves time and money, and reduces the stress of performing the donor corneal dissection in the operating room. In part because of the ability of the eye banks to provide high quality posterior lamellar corneal in a timely manner, DSAEK has become the standard of care for surgical management of corneal endothelial disease. The procedure that we are describing is the preparation of the posterior lamellar cornea at the eye bank for transplantation in DSAEK surgery (Figure 1).

Impact of high-fat diet and voluntary running on body weight and endothelial function in LDL receptor knockout mice.

PubMed

Langbein, Heike; Hofmann, Anja; Brunssen, Coy; Goettsch, Winfried; Morawietz, Henning

2015-05-01

Obesity and physical inactivity are important cardiovascular risk factors. Regular physical exercise has been shown to mediate beneficial effects in the prevention of cardiovascular diseases. However, the impact of physical exercise on endothelial function in proatherosclerotic low-density lipoprotein receptor deficient (LDLR(-/-)) mice has not been studied so far. Six-week-old male LDLR(-/-) mice were fed a standard diet or a high-fat diet (39 kcal% fat diet) for 20 weeks. The impact of high-fat diet and voluntary running on body weight and amount of white adipose tissue was monitored. Basal tone and endothelial function was investigated in aortic rings using a Mulvany myograph. LDLR(-/-) mice on high-fat diet had increased cumulative food energy intake, but also higher physical activity compared to mice on control diet. Body weight and amount of visceral and retroperitoneal white adipose tissue of LDLR(-/-) mice were significantly increased by high-fat diet and partially reduced by voluntary running. Endothelial function in aortae of LDLR(-/-) mice was impaired after 20 weeks on standard and high-fat diet and could not be improved by voluntary running. Basal tone showed a trend to be increased by high-fat diet. Voluntary running reduced body weight and amount of white adipose tissue in LDLR(-/-) mice. Endothelial dysfunction in LDLR(-/-) mice could not be improved by voluntary running. In a clinical context, physical exercise alone might not have an influence on functional parameters and LDL-C levels in patients with familial hypercholesterolemia. However, physical activity in these patients may be in general beneficial and should be performed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Surface modification and endothelialization of biomaterials as potential scaffolds for vascular tissue engineering applications.

PubMed

Ren, Xiangkui; Feng, Yakai; Guo, Jintang; Wang, Haixia; Li, Qian; Yang, Jing; Hao, Xuefang; Lv, Juan; Ma, Nan; Li, Wenzhong

2015-08-07

Surface modification and endothelialization of vascular biomaterials are common approaches that are used to both resist the nonspecific adhesion of proteins and improve the hemocompatibility and long-term patency of artificial vascular grafts. Surface modification of vascular grafts using hydrophilic poly(ethylene glycol), zwitterionic polymers, heparin or other bioactive molecules can efficiently enhance hemocompatibility, and consequently prevent thrombosis on artificial vascular grafts. However, these modified surfaces may be excessively hydrophilic, which limits initial vascular endothelial cell adhesion and formation of a confluent endothelial lining. Therefore, the improvement of endothelialization on these grafts by chemical modification with specific peptides and genes is now arousing more and more interest. Several active peptides, such as RGD, CAG, REDV and YIGSR, can be specifically recognized by endothelial cells. Consequently, graft surfaces that are modified by these peptides can exhibit targeting selectivity for the adhesion of endothelial cells, and genes can be delivered by targeting carriers to specific tissues to enhance the promotion and regeneration of blood vessels. These methods could effectively accelerate selective endothelial cell recruitment and functional endothelialization. In this review, recent developments in the surface modification and endothelialization of biomaterials in vascular tissue engineering are summarized. Both gene engineering and targeting ligand immobilization are promising methods to improve the clinical outcome of artificial vascular grafts.

Laminar shear stress modulates endothelial luminal surface stiffness in a tissue-specific manner.

PubMed

Merna, Nick; Wong, Andrew K; Barahona, Victor; Llanos, Pierre; Kunar, Balvir; Palikuqi, Brisa; Ginsberg, Michael; Rafii, Shahin; Rabbany, Sina Y

2018-04-17

Endothelial cells form vascular beds in all organs and are exposed to a range of mechanical forces that regulate cellular phenotype. We sought to determine the role of endothelial luminal surface stiffness in tissue-specific mechanotransduction of laminar shear stress in microvascular mouse cells and the role of arachidonic acid in mediating this response. Microvascular mouse endothelial cells were subjected to laminar shear stress at 4 dynes/cm 2 for 12 hours in parallel plate flow chambers that enabled real-time optical microscopy and atomic force microscopy measurements of cell stiffness. Lung endothelial cells aligned parallel to flow, while cardiac endothelial cells did not. This rapid alignment was accompanied by increased cell stiffness. The addition of arachidonic acid to cardiac endothelial cells increased alignment and stiffness in response to shear stress. Inhibition of arachidonic acid in lung endothelial cells and embryonic stem cell-derived endothelial cells prevented cellular alignment and decreased cell stiffness. Our findings suggest that increased endothelial luminal surface stiffness in microvascular cells may facilitate mechanotransduction and alignment in response to laminar shear stress. Furthermore, the arachidonic acid pathway may mediate this tissue-specific process. An improved understanding of this response will aid in the treatment of organ-specific vascular disease. © 2018 John Wiley & Sons Ltd.

Extracellular IL-33 cytokine, but not endogenous nuclear IL-33, regulates protein expression in endothelial cells.

PubMed

Gautier, Violette; Cayrol, Corinne; Farache, Dorian; Roga, Stéphane; Monsarrat, Bernard; Burlet-Schiltz, Odile; Gonzalez de Peredo, Anne; Girard, Jean-Philippe

2016-10-03

IL-33 is a nuclear cytokine from the IL-1 family that plays important roles in health and disease. Extracellular IL-33 activates a growing number of target cells, including group 2 innate lymphoid cells, mast cells and regulatory T cells, but it remains unclear whether intracellular nuclear IL-33 has additional functions in the nucleus. Here, we used a global proteomic approach based on high-resolution mass spectrometry to compare the extracellular and intracellular roles of IL-33 in primary human endothelial cells, a major source of IL-33 protein in human tissues. We found that exogenous extracellular IL-33 cytokine induced expression of a distinct set of proteins associated with inflammatory responses in endothelial cells. In contrast, knockdown of endogenous nuclear IL-33 expression using two independent RNA silencing strategies had no reproducible effect on the endothelial cell proteome. These results suggest that IL-33 acts as a cytokine but not as a nuclear factor regulating gene expression in endothelial cells.

Risk factors for eye bank preparation failure of Descemet membrane endothelial keratoplasty tissue.

PubMed

Vianna, Lucas M M; Stoeger, Christopher G; Galloway, Joshua D; Terry, Mark; Cope, Leslie; Belfort, Rubens; Jun, Albert S

2015-05-01

To assess the results of a single eye bank preparing a high volume of Descemet membrane endothelial keratoplasty (DMEK) tissues using multiple technicians to provide an overview of the experience and to identify possible risk factors for DMEK preparation failure. Cross-sectional study. setting: Lions VisionGift and Wilmer Eye Institute at Johns Hopkins Hospital. All 563 corneal tissues processed by technicians at Lions VisionGift for DMEK between October 2011 and May 2014 inclusive. Tissues were divided into 2 groups: DMEK preparation success and DMEK preparation failure. We compared donor characteristics, including past medical history. The overall tissue preparation failure rate was 5.2%. Univariate analysis showed diabetes mellitus (P = .000028) and its duration (P = .023), hypertension (P = .021), and hyperlipidemia or obesity (P = .0004) were more common in the failure group. Multivariate analysis showed diabetes mellitus (P = .0001) and hyperlipidemia or obesity (P = .0142) were more common in the failure group. Elimination of tissues from donors either with diabetes or with hyperlipidemia or obesity reduced the failure rate from 5.2% to 2.2%. Trends toward lower failure rates occurring with increased technician experience also were found. Our work showed that tissues from donors with diabetes mellitus (especially with longer disease duration) and hyperlipidemia or obesity were associated with higher failure rates in DMEK preparation. Elimination of tissues from donors either with diabetes mellitus or with hyperlipidemia or obesity reduced the failure rate. In addition, our data may provide useful initial guidelines and benchmark values for eye banks seeking to establish and maintain DMEK programs. Copyright © 2015 Elsevier Inc. All rights reserved.

Role of Vitamin C in the Function of the Vascular Endothelium

PubMed Central

Harrison, Fiona E.

2013-01-01

Abstract Significance: Vitamin C, or ascorbic acid, has long been known to participate in several important functions in the vascular bed in support of endothelial cells. These functions include increasing the synthesis and deposition of type IV collagen in the basement membrane, stimulating endothelial proliferation, inhibiting apoptosis, scavenging radical species, and sparing endothelial cell-derived nitric oxide to help modulate blood flow. Although ascorbate may not be able to reverse inflammatory vascular diseases such as atherosclerosis, it may well play a role in preventing the endothelial dysfunction that is the earliest sign of many such diseases. Recent Advances: Beyond simply preventing scurvy, evidence is mounting that ascorbate is required for optimal function of many dioxygenase enzymes in addition to those involved in collagen synthesis. Several of these enzymes regulate the transcription of proteins involved in endothelial function, proliferation, and survival, including hypoxia-inducible factor-1α and histone and DNA demethylases. More recently, ascorbate has been found to acutely tighten the endothelial permeability barrier and, thus, may modulate access of ascorbate and other molecules into tissues and organs. Critical Issues: The issue of the optimal cellular content of ascorbate remains unresolved, but it appears that low millimolar ascorbate concentrations are normal in most animal tissues, in human leukocytes, and probably in the endothelium. Although there may be little benefit of increasing near maximal cellular ascorbate concentrations in normal people, many diseases and conditions have either systemic or localized cellular ascorbate deficiency as a cause for endothelial dysfunction, including early atherosclerosis, sepsis, smoking, and diabetes. Future Directions: A key focus for future studies of ascorbate and the vascular endothelium will likely be to determine the mechanisms and clinical relevance of ascorbate effects on endothelial function, permeability, and survival in diseases that cause endothelial dysfunction. Antioxid. Redox Signal. 19, 2068–2083. PMID:23581713

[Progress of researches on the mechanism of cupping therapy].

PubMed

Cui, Shuai; Cui, Jin

2012-12-01

Cupping therapy of Chinese medicine is able to relieve a variety of diseases or clinical conditions, which results from the comprehensive effects of multiple types of stimulation exerted onto the regional acupoint areas. Among the stimuli, the negative pressure from cupping is one of the main factors inducing therapeutic effects. In the present paper, the authors review development of researches on the underlying mechanism of therapeutic effects of cupping-negative pressure from 1) the factor of intra-cup negative pressure; 2) influence of intra-cup negative pressure on cup-blackspot formation; 3) influence of cupping on regional blood vessels and blood flow; 4) effect of cupping on regional ultrastructure of the capillary in the raw-surface tissue; 5) effect of cupping-negative pressure on regional endothelial cells; and 6) biological effects of negative pressure drainage. Generally, cupping induced negative pressure can dilate local blood vessels to improve microcirculation, promote capillary endothelial cells repair, accelerate granulation and angiogenesis, etc., in the regional tissues, normalizing the patients' functional state at last.

Detection and quantification of mast cell, vascular endothelial growth factor, and microvessel density in human inflammatory periapical cysts and granulomas.

PubMed

Fonseca-Silva, T; Santos, C C O; Alves, L R; Dias, L C; Brito, M; De Paula, A M B; Guimarães, A L S

2012-09-01

To identify and quantify mast cell (MC), vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in human periapical cysts and granulomas. Archived samples of cysts (n = 40) and granulomas (n = 28) were sectioned and stained with toluidine blue. MCs were identified and counted. Immunohistochemical reactions were employed to evaluate the tissue expression of VEGF and vessels. MVD was estimated by determining the areas of tissue labelled with CD31 antibody. The data were analysed using the Mann-Whitney test (P < 0.05). MCs were observed in the peripheral regions of both lesion types, whilst VEGF and MVD were distributed in the stroma. The presence of MCs was higher in cysts than in granulomas (P < 0.05). VEGF and MVD expression were similar in these lesions. The highest number of MCs was observed in cysts. Moreover, the identification of VEGF and MVD was consistent with the immune mechanisms involved in the lesions. © 2012 International Endodontic Journal.

Epithelioid haemangiosarcoma in the ocular tissue of horses.

PubMed

Arenas-Gamboa, A M; Mansell, J

2011-05-01

Haemangiosarcomas (HSAs) are malignant tumours of endothelial cell origin. Epithelioid HSA is a variant of the histologically conventional HSA that has little or no morphological evidence of a vascular origin and has been reported rarely in domestic animals. The following report documents six cases of equine epithelioid HSA occurring in the ocular tissues of horses with a mean age of 19.8 years at the time of diagnosis. Microscopically, all of the lesions consisted of solid sheets or cords of epithelioid cells with rare narrow clefts or small spaces containing erythrocytes that were often the only feature indicating a vascular origin. On immunohistochemistry, the neoplastic cells expressed vimentin, CD31 and factor VIII-related antigen, but not cytokeratin, indicating an endothelial nature. Copyright © 2010 Elsevier Ltd. All rights reserved.

Nitric-oxide synthase trafficking inducer is a pleiotropic regulator of endothelial cell function and signaling

PubMed Central

2017-01-01

Endothelial nitric-oxide synthase (eNOS) and its bioactive product, nitric oxide (NO), mediate many endothelial cell functions, including angiogenesis and vascular permeability. For example, vascular endothelial growth factor (VEGF)-mediated angiogenesis is inhibited upon reduction of NO bioactivity both in vitro and in vivo. Moreover, genetic disruption or pharmacological inhibition of eNOS attenuates angiogenesis during tissue repair, resulting in delayed wound closure. These observations emphasize that eNOS-derived NO can promote angiogenesis. Intriguingly, eNOS activity is regulated by nitric-oxide synthase trafficking inducer (NOSTRIN), which sequesters eNOS, thereby attenuating NO production. This has prompted significant interest in NOSTRIN's function in endothelial cells. We show here that NOSTRIN affects the functional transcriptome of endothelial cells by down-regulating several genes important for invasion and angiogenesis. Interestingly, the effects of NOSTRIN on endothelial gene expression were independent of eNOS activity. NOSTRIN also affected the expression of secreted cytokines involved in inflammatory responses, and ectopic NOSTRIN overexpression functionally restricted endothelial cell proliferation, invasion, adhesion, and VEGF-induced capillary tube formation. Furthermore, NOSTRIN interacted directly with TNF receptor-associated factor 6 (TRAF6), leading to the suppression of NFκB activity and inhibition of AKT activation via phosphorylation. Interestingly, TNF-α-induced NFκB pathway activation was reversed by NOSTRIN. We found that the SH3 domain of NOSTRIN is involved in the NOSTRIN-TRAF6 interaction and is required for NOSTRIN-induced down-regulation of endothelial cell proteins. These results have broad biological implications, as aberrant NOSTRIN expression leading to deactivation of the NFκB pathway, in turn triggering an anti-angiogenic cascade, might inhibit tumorigenesis and cancer progression. PMID:28235804

Comparison of the relaxing actions of acetylcholine and substance P in smooth muscle of the guinea-pig aorta.

PubMed

Hozumi, T; Fukuta, H; Suzuki, H

1997-04-01

The relationship between relaxation produced by acetylcholine (ACh) or substance P (SP) and tissue cyclic GMP content was investigated in the isolated guinea-pig aorta. ACh and SP relaxed aortic rings precontracted with noradrenaline (NA) or high-K solution ([K+]o = 38.8 mM), in an endothelium-dependent manner. The amplitude of relaxation was larger for SP than for ACh. Nitroarginine inhibited ACh-induced but not SP-induced relaxation in NA-contraction, while this chemical inhibited both ACh- and SP-induced relaxations in high-K contraction. The tissue cyclic GMP content was not changed by nitroarginine or by removal of endothelial cells, but was elevated by stimulation with NA, ACh or SP by a factor of about 3, 5 or 11 times, respectively. These actions of ACh or SP were endothelium-dependent, and were inhibited by nitroarginine and remained unaltered by high-K solution. Thus, ACh and SP relax muscles indirectly by releasing endothelial factors, and the former by releasing mainly an endothelium-derived relaxing factor (EDRF), and the latter by releasing EDRF and other unidentified factors. As the relaxing actions of the latter factors are inhibited by high-K solution with no relation to the production of cyclic GMP, an involvement of hyperpolarizing factor, possibly EDHF, is suggested.

Increase in acid sphingomyelinase level in human retinal endothelial cells and CD34+ circulating angiogenic cells isolated from diabetic individuals is associated with dysfunctional retinal vasculature and vascular repair process in diabetes

PubMed Central

Kady, Nermin; Yan, Yuanqing; Salazar, Tatiana; Wang, Qi; Chakravarthy, Harshini; Huang, Chao; Beli, Eleni; Navitskaya, Svetlana; Grant, Maria; Busik, Julia

2017-01-01

Background Diabetic retinopathy (DR) is a microvascular disease that results from retinal vascular degeneration and defective repair due to diabetes induced endothelial progenitor dysfunction. Objective Understanding key molecular factors involved in vascular degeneration and repair is paramount for developing effective DR treatment strategies. We propose that diabetes-induced activation of acid sphingomyelinase (ASM) plays essential role in retinal endothelial and CD34+ circulating angiogenic cell (CAC) dysfunction in diabetes. Methods Human retinal endothelial cells (HRECs) isolated from control and diabetic donor tissue and human CD34+ CACs from control and diabetic patients were used in this study. ASM mRNA and protein expression was assessed by quantitative PCR and ELISA, respectively. To evaluate the effect of diabetes-induced ASM on HRECs and CD34+ CACs function, tube formation, CAC incorporation into endothelial tubes, and diurnal release of CD34+ CACs in diabetic individuals was determined. Results ASM expression level was significantly increased in HRECs isolated from diabetic compared to control donor tissue, as well as CD34+CACs and plasma of diabetic patients. A significant decrease in tube area was observed in HRECs from diabetic donors as compared to control HRECs. The tube formation deficiency was associated with increased expression of ASM in diabetic HRECs. Moreover, diabetic CD34+ CACs with high ASM showed defective incorporation into endothelial tubes. Diurnal release of CD34+ CACs was disrupted with the rhythmicity lost in diabetic patients. Conclusion Collectively, these findings support that diabetes-induced ASM upregulation has a marked detrimental effect on both retinal endothelial cells and CACs. PMID:28457994

Tissue Inhibitor of Metalloproteinase-3 (TIMP3) Promotes Endothelial Apoptosis via a Caspase-Independent Mechanism

PubMed Central

Qi, Jian Hua; Anand-Apte, Bela

2015-01-01

Tissue Inhibitor of Metalloproteinases-3 (TIMP3) is a tumor suppressor and a potent inhibitor of angiogenesis. TIMP3 exerts its anti-angiogenic effect via a direct interaction with vascular endothelial growth factor (VEGF) receptor-2 (KDR) and inhibition of proliferation, migration and tube formation of endothelial cells (ECs). TIMP3 has also been shown to induce apoptosis in some cancer cells and vascular smooth muscle cells via MMP inhibition and caspase-dependent mechanisms. In this study, we examined the molecular mechanisms of TIMP3-mediated apoptosis in endothelial cells. We have previously demonstrated that mice developed smaller tumors with decreased vascularity when injected with breast carcinoma cells overexpressing TIMP3, than with control breast carcinoma cells. TIMP3 overexpression resulted in increased apoptosis in human breast carcinoma (MDA-MB435) in vivo but not in vitro. However, TIMP3 could induce apoptosis in endothelial cells (ECs) in vitro. The apoptotic activity of TIMP3 in ECs appears to be independent of MMP inhibitory activity. Furthermore, the equivalent expression of functional TIMP3 promoted apoptosis and caspase activation in endothelial cells expressing KDR (PAE/KDR), but not in endothelial cells expressing PDGF beta-receptor (PAE/β-R). Surprisingly, the apoptotic activity of TIMP3 appears to be independent of caspases. TIMP3 inhibited matrix-induced focal adhesion kinase (FAK) tyrosine phosphorylation and association with paxillin and disrupted the incorporation of β3 integrin, FAK and paxillin into focal adhesion contacts on the matrix, which were not affected by caspase inhibitors. Thus, TIMP3 may induce apoptosis in ECs by triggering a caspase-independent cell death pathway and targeting a FAK-dependent survival pathway. PMID:25558000

Photonic Monitoring in Real-time of Vascular Endothelial Growth Factor Receptor 2 (VEGFR2) Gene Expression Under Relaxin-induced Conditions in a Novel Murine Wound Model

USDA-ARS?s Scientific Manuscript database

Relaxin is known to promote vascular endotheilial growth factor (VEGF) expression in reproductive tissue and successful wound-healing is dependent upon good vascularization of wound sites, a process that relaxin may facilitate. Thus, the objective of this study was to evaluate the efficacy of relaxi...

Placenta growth factor not vascular endothelial growth factor A or C can predict the early recurrence after radical resection of hepatocellular carcinoma.

PubMed

Ho, Ming-Chih; Chen, Chiung-Nien; Lee, Hsinyu; Hsieh, Fon-Jou; Shun, Chia-Tung; Chang, Chi-Lun; Lai, Yeun-Tyng; Lee, Po-Huang

2007-06-08

The purpose of this study was to evaluate the relationship between the expression of PlGF in tumor tissue and clinical outcomes in HCC patients. Tumor PlGF and vascular endothelial growth factor (VEGF)-A and VEGF-C mRNA were analyzed. Results demonstrated that patients with PlGF expression levels higher than median tended to have early recurrence compared to patients with PlGF expression lower than median (P=.031). In patients with AJCC stage II-III disease, this difference was even more significant (P=.002). In contrast, VEGF-A and VEGF-C could not predict early recurrence-free survival. Since PlGF expression correlated with early recurrence of HCC, PlGF may be an important prognostic indicator in HCC.

Characterization of the expression and clinical features of epidermal growth factor receptor and vascular endothelial growth factor receptor-2 in esophageal carcinoma

PubMed Central

NIYAZ, MADINIYAT; ANWER, JURAT; LIU, HUI; ZHANG, LIWEI; SHAYHEDIN, ILYAR; AWUT, IDIRIS

2015-01-01

The present study aimed to understand the expression characteristics of epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor-2 (VEGFR-2) in individuals of Uygur, Han and Kazak ethnicity with esophageal carcinoma in Xinjiang (China) and their interrelation analysis, and to investigate the expression differences in these genes between esophageal carcinoma and pericarcinoma tissue samples, and between the three ethnic groups. The expression levels of EGFR and VEGFR-2 from 119 pairs of esophageal carcinoma tissue and corresponding pericarcinoma tissue from Uygur, Han and Kazak patients with esophageal carcinoma were detected by immunohistochemistry following surgical resection, and an additional five carcinoma in situ specimens were also tested. The relative expression was analyzed among the ethnic groups and clinicopathological parameters. The positive rate of EGFR in esophageal carcinoma tissue from patients of Uygur, Han and Kazak heritage was 70.73, 68.42 and 67.5%, respectively. For VEGFR-2 the positive rate was 73.17, 68.42 and 67.5%, respectively. No significant difference was detected in their expression between the three ethnic groups (P>0.05); however, EGFR and VEGFR-2 overexpression were correlated with lymph node metastasis (P<0.05). VEGF expression was also correlated with the expression of VEGFR-2 in esophageal carcinoma tissues. EGFR was positive in carcinoma in situ samples, while VEGFR-2 was negative. The overexpression of EGFR is therefore an early event and may have a significant role in the progression of esophageal carcinoma pathogenesis. EGFR overexpression may correlate with the expression of VEGFR-2 in esophageal cancer. These results may aid the early diagnosis of esophageal cancer, and the development of individual target treatment in the future. PMID:26788193

Vascular Morphogenesis in the Context of Inflammation: Self-Organization in a Fibrin-Based 3D Culture System.

PubMed

Rüger, Beate M; Buchacher, Tanja; Giurea, Alexander; Kubista, Bernd; Fischer, Michael B; Breuss, Johannes M

2018-01-01

Introduction: New vessel formation requires a continuous and tightly regulated interplay between endothelial cells with cells of the perivascular microenvironment supported by mechanic-physical and chemical cues from the extracellular matrix. Aim: Here we investigated the potential of small fragments of synovial tissue to form de novo vascular structures in the context of inflammation within three dimensional (3D) fibrin-based matrices in vitro , and assessed the contribution of mesenchymal stromal cell (MSC)-immune cell cross-talk to neovascularization considering paracrine signals in a fibrin-based co-culture model. Material and Methods: Synovial tissue fragments from patients with rheumatoid arthritis (RA) and inflammatory osteoarthritis (OA) were cultivated within 3D fibrin matrices for up to 4 weeks. Cellular and structural re-arrangement of the initially acellular matrix were documented by phase contrast microscopy and characterized by confocal laser-scanning microscopy of topographically intact 3D cultures and by immunohistochemistry. MSC-peripheral blood mononuclear cell (PBMC) co-cultures in the 3D fibrin system specifically addressed the influence of perivascular cell interactions to neo-vessel formation in a pro-inflammatory microenvironment. Cytokine levels in the supernatants of cultured explant tissues and co-cultures were evaluated by the Bio-Plex cytokine assay and ELISA. Results: Vascular outgrowth from the embedded tissue into the fibrin matrix was preceded by leukocyte egress from the tissue fragments. Neo-vessels originating from both the embedded sample and from clusters locally formed by emigrated mononuclear cells were consistently associated with CD45 + leukocytes. MSC and PBMC in co-culture formed vasculogenic clusters. Clusters and cells with endothelial phenotype emerging from them, were surrounded by a collagen IV scaffold. No vascular structures were observed in control 3D monocultures of PBMC or MSC. Paracrine signals released by cultured OA tissue fragments corresponded with elevated levels of granulocyte-colony stimulating factor, vascular endothelial growth factor and interleukin-6 secreted by MSC-PBMC co-cultures. Conclusion: Our results show that synovial tissue fragments with immune cell infiltrates have the potential to form new vessels in initially avascular 3D fibrin-based matrices. Cross-talk and cluster formation of MSC with immune cells within the 3D fibrin environment through self-organization and secretion of pro-angiogenic paracrine factors can support neo-vessel growth.

Synergistic Effects of Vascular Endothelial Growth Factor on Bone Morphogenetic Proteins Induced Bone Formation In Vivo: Influencing Factors and Future Research Directions

PubMed Central

Li, Bo; Wang, Hai; Qiu, Guixing; Su, Xinlin

2016-01-01

Vascular endothelial growth factor (VEGF) and bone morphogenetic proteins (BMPs), as key mediators in angiogenesis and osteogenesis, are used in a combined delivery manner as a novel strategy in bone tissue engineering. VEGF has the potential to enhance BMPs induced bone formation. Both gene delivery and material-based delivery systems were incorporated in previous studies to investigate the synergistic effects of VEGF and BMPs. However, their results were controversial due to variation of methods incorporated in different studies. Factors influencing the synergistic effects of VEGF on BMPs induced bone formation were identified and analyzed in this review to reduce confusion on this issue. The potential mechanisms and directions of future studies were also proposed here. Further investigating mechanisms of the synergistic effects and optimizing these influencing factors will help to generate more effective bone regeneration. PMID:28070506

Vascular biology in altered gravity conditions

NASA Astrophysics Data System (ADS)

Bradamante, Silvia; Maier, Janette A. M.; Duncker, Dirk J.

2005-10-01

The physical environment of Endothelial Cells profoundly affects their gene expression, structure, function, growth differentiation and apoptosis. However, the mechanisms by which the genetic and local growth determinants driving morphogenesis are established and maintained remain unknown. Understanding how gravity affects vascular cells will offer new insights for novel therapeutical approaches for cardiovascular disease in general. In terms of tissue engineering and stem-cell therapy, significant future developments will depend on a profound understanding of the cellular and molecular basis of angiogenesis and of the biology of circulating Endothelial Precursor Cells. this MAP project has demonstrated how modelled microgravity influences endothelial proliferation and differentiation with the involvement of anti-angiogenic factors that may be responsible for the non-spontaneous formation of blood vessels.

Endothelial cell regulation of leukocyte infiltration in inflammatory tissues

PubMed Central

Mantovani, A.; Introna, M.; Dejana, E.

1995-01-01

Endothelial cells play an important, active role in the onset and regulation of inflammatory and immune reactions. Through the production of chemokines they attract leukocytes and activate their adhesive receptors. This leads to the anchorage of leukocytes to the adhesive molecules expressed on the endothelial surface. Leukocyte adhesion to endothelial cells is frequently followed by their extravasation. The mechanisms which regulate the passage of leukocytes through endothelial clefts remain to be clarified. Many indirect data suggest that leukocytes might transfer signals to endothelial cells both through the release of active agents and adhesion to the endothelial cell surface. Adhesive molecules (such as PECAM) on the endothelial cell surface might also ‘direct’ leukocytes through the intercellular junction by haptotaxis. The information available on the molecular structure and functional properties of endothelial chemokines, adhesive molecules or junction organization is still fragmentary. Further work is needed to clarify how they interplay in regulating leukocyte infiltration into tissues. PMID:18475659

Age-related changes in endothelial function and blood flow regulation.

PubMed

Toda, Noboru

2012-02-01

Vascular endothelial dysfunction is regarded as a primary phenotypic expression of normal human aging. This senescence-induced disorder is the likely culprit underlying the increased cardiovascular and metabolic disease risks associated with aging. The rate of this age-dependent deterioration is largely influenced by the poor-quality lifestyle choice, such as smoking, sedentary daily life, chronic alcohol ingestion, high salt intake, unbalanced diet, and mental stress; and it is accelerated by cardiovascular and metabolic diseases. Although minimizing these detrimental factors is the best course of action, nonetheless chronological age steadily impairs endothelial function through reduced endothelial nitric oxide synthase (eNOS) expression/action, accelerated nitric oxide (NO) degradation, increased phosphodiesterase activity, inhibition of NOS activity by endogenous NOS inhibitors, increased production of reactive oxygen species, inflammatory reactions, decreased endothelial progenitor cell number and function, and impaired telomerase activity or telomere shortening. Endothelial dysfunction in regional vasculatures results in cerebral hypoperfusion triggering cognitive dysfunction and Alzheimer's disease, coronary artery insufficiency, penile erectile dysfunction, and circulatory failures in other organs and tissues. Possible prophylactic measures to minimize age-related endothelial dysfunction are also summarized in this review. Copyright © 2011 Elsevier Inc. All rights reserved.

Delayed brain radiation necrosis: pathological review and new molecular targets for treatment.

PubMed

Furuse, Motomasa; Nonoguchi, Naosuke; Kawabata, Shinji; Miyatake, Shin-Ichi; Kuroiwa, Toshihiko

2015-12-01

Delayed radiation necrosis is a well-known adverse event following radiotherapy for brain diseases and has been studied since the 1930s. The primary pathogenesis is thought to be the direct damage to endothelial and glial cells, particularly oligodendrocytes, which causes vascular hyalinization and demyelination. This primary pathology leads to tissue inflammation and ischemia, inducing various tissue protective responses including angiogenesis. Macrophages and lymphocytes then infiltrate the surrounding areas of necrosis, releasing inflammatory cytokines such as interleukin (IL)-1α, IL-6, and tumor necrosis factor (TNF)-α. Microglia also express these inflammatory cytokines. Reactive astrocytes play an important role in angiogenesis, expressing vascular endothelial growth factor (VEGF). Some chemokine networks, like the CXCL12/CXCR4 axis, are upregulated by tissue inflammation. Hypoxia may mediate the cell-cell interactions among reactive astrocytes, macrophages, and microglial cells around the necrotic core. Recently, bevacizumab, an anti-VEGF antibody, has demonstrated promising results as an alternative treatment for radiation necrosis. The importance of VEGF in the pathophysiology of brain radiation necrosis is being recognized. The discovery of new molecular targets could facilitate novel treatments for radiation necrosis. This literature review will focus on recent work characterizing delayed radiation necrosis in the brain.

Diabetes mellitus and ischemic diseases: molecular mechanisms of vascular repair dysfunction.

PubMed

Howangyin, Kiave Yune; Silvestre, Jean-Sébastien

2014-06-01

In patients with diabetes mellitus, the ability of ischemic tissue to synchronize the molecular and cellular events leading to restoration of tissue perfusion in response to the atherosclerotic occlusion of a patent artery is markedly impaired. As a consequence, adverse tissue remodeling and the extent of ischemic injury are intensified, leading to increased morbidity and mortality. Growing evidence from preclinical and clinical studies has implicated alterations in hypoxia-inducible factor 1 levels in the abrogation of proangiogenic pathways, including vascular endothelial growth factor A/phosphoinositide 3' kinase/AKT/endothelial nitric oxide synthase and in the activation of antiangiogenic signals characterized by accumulation of advanced glycation end products, reactive oxygen species overproduction, and endoplasmic reticulum stress. In addition, the diabetic milieu shows a switch toward proinflammatory antiregenerative pathways. Finally, the mobilization, subsequent recruitment, and the proangiogenic potential of the different subsets of angiogenesis-promoting bone marrow-derived cells are markedly impaired in the diabetic environment. In this review, we will give an overview of the current understanding on the signaling molecules contributing to the diabetes mellitus-induced impairment of postischemic revascularization mainly in the setting of myocardial infarction or critical limb ischemia. © 2014 American Heart Association, Inc.

Potential applications of low-energy shock waves in functional urology.

PubMed

Wang, Hung-Jen; Cheng, Jai-Hong; Chuang, Yao-Chi

2017-08-01

A shock wave, which carries energy and can propagate through a medium, is a type of continuous transmitted sonic wave with a frequency of 16 Hz-20 MHz. It is accompanied by processes involving rapid energy transformations. The energy associated with shock waves has been harnessed and used for various applications in medical science. High-energy extracorporeal shock wave therapy is the most successful application of shock waves, and has been used to disintegrate urolithiasis for 30 years. At lower energy levels, however, shock waves have enhanced expression of vascular endothelial growth factor, endothelial nitric oxide synthase, proliferating cell nuclear antigen, chemoattractant factors and recruitment of progenitor cells; shock waves have also improved tissue regeneration. Low-energy shock wave therapy has been used clinically with musculoskeletal disorders, ischemic cardiovascular disorders and erectile dysfunction, through the mechanisms of neovascularization, anti-inflammation and tissue regeneration. Furthermore, low-energy shock waves have been proposed to temporarily increase tissue permeability and facilitate intravesical drug delivery. The present review article provides information on the basics of shock wave physics, mechanisms of action on the biological system and potential applications in functional urology. © 2017 The Japanese Urological Association.

Multilineage differentiation of rhesus monkey embryonic stem cells in three-dimensional culture systems

NASA Technical Reports Server (NTRS)

Chen, Silvia S.; Revoltella, Roberto P.; Papini, Sandra; Michelini, Monica; Fitzgerald, Wendy; Zimmerberg, Joshua; Margolis, Leonid

2003-01-01

In the course of normal embryogenesis, embryonic stem (ES) cells differentiate along different lineages in the context of complex three-dimensional (3D) tissue structures. In order to study this phenomenon in vitro under controlled conditions, 3D culture systems are necessary. Here, we studied in vitro differentiation of rhesus monkey ES cells in 3D collagen matrixes (collagen gels and porous collagen sponges). Differentiation of ES cells in these 3D systems was different from that in monolayers. ES cells differentiated in collagen matrixes into neural, epithelial, and endothelial lineages. The abilities of ES cells to form various structures in two chemically similar but topologically different matrixes were different. In particular, in collagen gels ES cells formed gland-like circular structures, whereas in collagen sponges ES cells were scattered through the matrix or formed aggregates. Soluble factors produced by feeder cells or added to the culture medium facilitated ES cell differentiation into particular lineages. Coculture with fibroblasts in collagen gel facilitated ES cell differentiation into cells of a neural lineage expressing nestin, neural cell adhesion molecule, and class III beta-tubulin. In collagen sponges, keratinocytes facilitated ES cell differentiation into cells of an endothelial lineage expressing factor VIII. Exogenous granulocyte-macrophage colony-stimulating factor further enhanced endothelial differentiation. Thus, both soluble factors and the type of extracellular matrix seem to be critical in directing differentiation of ES cells and the formation of tissue-like structures. Three-dimensional culture systems are a valuable tool for studying the mechanisms of these phenomena.

UP-REGULATION OF TISSUE FACTOR IN HUMAN PULMONARY ARTERY ENDOTHELIAL CELLS AFTER ULTRAFINE PARTICLE EXPOSURE

EPA Science Inventory

Background: Epidemiology studies have linked exposure to pollutant particles to

increased cardiovascular mortality and morbidity, but the mechanisms remain unknown.

Objectives: We tested the hypothesis that the ultrafine fraction of ambient pollutant

particle...

[Endothelial microparticles (EMP) in physiology and pathology].

PubMed

Sierko, Ewa; Sokół, Monika; Wojtukiewicz, Marek Z

2015-08-18

Endothelial microparticles (EMP) are released from endothelial cells (ECs) in the process of activation and/or apoptosis. They harbor adhesive molecules, enzymes, receptors and cytoplasmic structures and express a wide range of various constitutive antigens, typical for ECs, at their surface. Under physiological conditions the concentration of EMP in the blood is clinically insignificant. However, it was reported that under pathological conditions EMP concentration in the blood might slightly increase and contribute to blood coagulation, angiogenesis and inflammation. It has been shown that EMP directly and indirectly contribute to the activation of blood coagulation. Endothelial microparticles directly participate in blood coagulation through their surface tissue factor (TF) - a major initiator of blood coagulation. Furthermore, EMP exhibit procoagulant potential via expression of negatively charged phospholipids at their surface, which may promote assembly of coagulation enzymes (TF/VII, tenases and prothrombinase complexes), leading to thrombus formation. In addition, they provide a binding surface for coagulation factors: IXa, VIII, Va and IIa. Moreover, it is possible that EMP transfer TF from TF-bearing EMP to activated platelets and monocytes by binding them through adhesion molecules. Also, EMP express von Willebrand factor, which may facilitate platelet aggregation. Apart from their procoagulant properties, it was demonstrated that EMP may express adhesive molecules and metalloproteinases (MMP-2, MMP-9) at their surface and release growth factors, which may contribute to angiogenesis. Additionally, surface presence of C3 and C4 - components of the classical pathway - suggests pro-inflammatory properties of these structures. This article contains a summary of available data on the biology and pathophysiology of endothelial microparticles and their potential role in blood coagulation, angiogenesis and inflammation.

Supercritical carbon dioxide extracted extracellular matrix material from adipose tissue.

PubMed

Wang, Jun Kit; Luo, Baiwen; Guneta, Vipra; Li, Liang; Foo, Selin Ee Min; Dai, Yun; Tan, Timothy Thatt Yang; Tan, Nguan Soon; Choong, Cleo; Wong, Marcus Thien Chong

2017-06-01

Adipose tissue is a rich source of extracellular matrix (ECM) material that can be isolated by delipidating and decellularizing the tissue. However, the current delipidation and decellularization methods either involve tedious and lengthy processes or require toxic chemicals, which may result in the elimination of vital proteins and growth factors found in the ECM. Hence, an alternative delipidation and decellularization method for adipose tissue was developed using supercritical carbon dioxide (SC-CO 2 ) that eliminates the need of any harsh chemicals and also reduces the amount of processing time required. The resultant SC-CO 2 -treated ECM material showed an absence of nuclear content but the preservation of key proteins such as collagen Type I, collagen Type III, collagen Type IV, elastin, fibronectin and laminin. In addition, other biological factors such as glycosaminoglycans (GAGs) and growth factors such as basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) were also retained. Subsequently, the resulting SC-CO 2 -treated ECM material was used as a bioactive coating on tissue culture plastic (TCP). Four different cell types including adipose tissue-derived mesenchymal stem cells (ASCs), human umbilical vein endothelial cells (HUVECs), immortalized human keratinocyte (HaCaT) cells and human monocytic leukemia cells (THP-1) were used in this study to show that the SC-CO 2 -treated ECM coating can be potentially used for various biomedical applications. The SC-CO 2 -treated ECM material showed improved cell-material interactions for all cell types tested. In addition, in vitro scratch wound assay using HaCaT cells showed that the presence of SC-CO 2 -treated ECM material enhanced keratinocyte migration whilst the in vitro cellular studies using THP-1-derived macrophages showed that the SC-CO 2 -treated ECM material did not evoke pro-inflammatory responses from the THP-1-derived macrophages. Overall, this study shows the efficacy of SC-CO 2 method for delipidation and decellularization of adipose tissue whilst retaining its ECM and its subsequent utilization as a bioactive surface coating material for soft tissue engineering, angiogenesis and wound healing applications. Copyright © 2017 Elsevier B.V. All rights reserved.

[Establishment and evaluation of extracorporeal circulation model in rats].

PubMed

Xie, Xiao-Jun; Tao, Kai-Yu; Tang, Meng-Lin; Du, Lei; An, Qi; Lin, Ke; Gan, Chang-Ping; Chen, You-Wen; Luo, Shu-Hua

2012-09-01

To establish an extracorporeal circulation (ECC) rat model, and evaluate the inflammatory response and organ injury induced in the model. SD rats were anesthetized and cannulated from right common carotid artery to left femoral vein to establish the bypass of extracorporeal circulation. Then the rats were randomly divided into ECC group and sham group. The rats in ECC group were subjected to extracorporeal circulation for 2 hours and then rest for 2 hours, while the rats in sham group were only observed for 4 hours without extracorporeal circulation. After that, blood routine examination, blood gas analysis, the measurement of pro-inflammatory factors in bronchoalveolar lavage fluid and lung tissue were performed to evaluate the lung injury induced by ECC. Circulating endothelial cells were also calculated by flow cytometry to assess the vascular endothelial injury. At 2 hours after ECC, red blood cell counts in both groups kept normal, while leukocyte and neutrophil counts, plasmatic tumor necrosis factor-a level and neutrophil elastase level, circulating endothelial cells in the rats of ECC group were significantly higher than those in sham group. Tumor necrosis factor-alpha in bronchoalveolar lavage fluid and water content in lung of the ECC rats were also significantly higher, while the oxygenation index was significantly lower. Neutrophil infiltration was also observed in lung tissues with increased thickness of alveolar membrane in ECC group. The ECC model established from right common carotid artery to left femoral vein in our study can successfully induce systemic inflammatory response, and acute lung injury associated with inflammation.

Markers of endothelial dysfunction and severity of hypoxaemia in the Eisenmenger syndrome.

PubMed

de P S Soares, Rosangela; Maeda, Nair Y; Bydlowski, Sérgio P; Lopes, Antonio Augusto

2005-10-01

Endothelial dysfunction has been reported in hypoxaemic patients with the Eisenmenger syndrome, but a direct correlation between levels of endothelial markers and the severity of hypoxaemia has not been explored. With this in mind, we compared the levels in the plasma of tissue-type plasminogen activator, thrombomodulin, and von Willebrand factor in 25 patients with the Eisenmenger syndrome. They had a median age of 31 years, and were divided into 2 groups according to their recent clinical history. Thus, 18 patients were stable, being in functional class II or III, seen as outpatients, and having peripheral saturations of oxygen of 89 plus or minus 5 percent. In contrast, 7 patients were unstable, showing episodes of symptoms placing them in functional class IV, requiring care in hospital, and manifesting saturations of oxygen of 77 plus or minus 5 percent. We were able to follow 12 patients, 8 who were stable and 4 unstable, for 24 months. At baseline, levels of von Willebrand factor were higher in the unstable patients when compared to those who were stable, at 142 plus or minus 29 and 110 plus or minus 25 units per decilitre, respectively (p equal to 0.013). This correlated positively with oxygen desaturation (p less than 0.020). The structural abnormalities also correlated positively with the magnitude of hypoxaemia (p less than 0.020). Levels remained higher in the unstable patients throughout the period of follow-up (p equal to 0.006). Tissue-type plasminogen activator was also increased, at 14.3 plus or minus 8.4 versus 6.5 plus or minus 2.7 nanograms per millilitre in controls (p less than 0.001), whereas thrombomodulin was decreased, with values of 14.4 versus 34.6 nanograms per millilitre in controls (p for median values of less than 0.001). There was no correlation with saturations of oxygen. We conclude that measurement of von Willebrand factor, as compared with tissue-type plasminogen activator and thrombomodulin, will prove a better marker of endothelial response to hypoxaemia in patients with the Eisenmenger syndrome.

Evaluation of Energy Balance on Human Telomerase Reverse Transcriptase (hTERT) Alternative Splicing by Semi-quantitative RT-PCR in Human Umbilical Vein Endothelial Cells.

PubMed

Behjati, Mohaddeseh; Hashemi, Mohammad; Kazemi, Mohammad; Salehi, Mansoor; Javanmard, Shaghayegh Haghjooy

2017-01-01

Decreased high-energy phosphate level is involved in endothelial cell injury and dysfunction. Reduced telomerase activity in endothelial cells in parallel with reduced energy levels might be due to altered direction of alternative splicing machine as a complication of depleted energy during the process of atherosclerosis. Isolated human umbilical vein endothelial cells (HUVECs) were treated for 24 hours by oligomycine (OM) and 2-deoxy glucose (2-DG). After 24 hours, the effect of energy depletion on telomerase splicing pattern was evaluated using RT-PCR. Indeed, in both treated and untargeted cells, nitric oxide (NO) and von Willebrand factor (vWF) were measured. ATP was depleted in treated cells by 43.9% compared with control group. We observed a slight decrease in NO levels ( P = 0.09) and vWF ( P = 0.395) in the setting of 49.36% ATP depletion. In both groups, no telomerase gene expression was seen. Telomerase and housekeeping gene expression were found in positive control group (colon cancer tissue) and sample tissue. The absence of telomerase gene expression in HUVECs might be due to the mortality of these cells or the low level of telomerase gene expression in these cells under normal circumstances.

Biomarkers of coronary endothelial health: correlation with invasive measures of collateral function, flow and resistance in chronically occluded coronary arteries and the effect of recanalization.

PubMed

Ladwiniec, Andrew; Ettelaie, Camille; Cunnington, Michael S; Rossington, Jennifer; Thackray, Simon; Alamgir, Farquad; Hoye, Angela

2016-06-01

In the presence of a chronically occluded coronary artery, the collateral circulation matures by a process of arteriogenesis; however, there is considerable variation between individuals in the functional capacity of that collateral network. This could be explained by differences in endothelial health and function. We aimed to examine the relationship between the functional extent of collateralization and levels of biomarkers that have been shown to relate to endothelial health. We measured four potential biomarkers of endothelial health in 34 patients with mature collateral networks who underwent a successful percutaneous coronary intervention (PCI) for a chronic total coronary occlusion (CTO) before PCI and 6-8 weeks after PCI, and examined the relationship of biomarker levels with physiological measures of collateralization. We did not find a significant change in the systemic levels of sICAM-1, sE-selectin, microparticles or tissue factor 6-8 weeks after PCI. We did find an association between estimated retrograde collateral flow before CTO recanalization and lower levels of sICAM-1 (r=0.39, P=0.026), sE-selectin (r=0.48, P=0.005) and microparticles (r=0.38, P=0.03). Recanalization of a CTO and resultant regression of a mature collateral circulation do not alter systemic levels of sICAM-1, sE-selectin, microparticles or tissue factor. The identified relationship of retrograde collateral flow with sICAM-1, sE-selectin and microparticles is likely to represent an association with an ability to develop collaterals rather than their presence and extent.

Improvement of adipose tissue-derived cells by low-energy extracorporeal shock wave therapy.

PubMed

Priglinger, Eleni; Schuh, Christina M A P; Steffenhagen, Carolin; Wurzer, Christoph; Maier, Julia; Nuernberger, Sylvia; Holnthoner, Wolfgang; Fuchs, Christiane; Suessner, Susanne; Rünzler, Dominik; Redl, Heinz; Wolbank, Susanne

2017-09-01

Cell-based therapies with autologous adipose tissue-derived cells have shown great potential in several clinical studies in the last decades. The majority of these studies have been using the stromal vascular fraction (SVF), a heterogeneous mixture of fibroblasts, lymphocytes, monocytes/macrophages, endothelial cells, endothelial progenitor cells, pericytes and adipose-derived stromal/stem cells (ASC) among others. Although possible clinical applications of autologous adipose tissue-derived cells are manifold, they are limited by insufficient uniformity in cell identity and regenerative potency. In our experimental set-up, low-energy extracorporeal shock wave therapy (ESWT) was performed on freshly obtained human adipose tissue and isolated adipose tissue SVF cells aiming to equalize and enhance stem cell properties and functionality. After ESWT on adipose tissue we could achieve higher cellular adenosine triphosphate (ATP) levels compared with ESWT on the isolated SVF as well as the control. ESWT on adipose tissue resulted in a significantly higher expression of single mesenchymal and vascular marker compared with untreated control. Analysis of SVF protein secretome revealed a significant enhancement in insulin-like growth factor (IGF)-1 and placental growth factor (PLGF) after ESWT on adipose tissue. Summarizing we could show that ESWT on adipose tissue enhanced the cellular ATP content and modified the expression of single mesenchymal and vascular marker, and thus potentially provides a more regenerative cell population. Because the effectiveness of autologous cell therapy is dependent on the therapeutic potency of the patient's cells, this technology might raise the number of patients eligible for autologous cell transplantation. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Effect of Melilotus suaveolens extract on pulmonary microvascular permeability by downregulating vascular endothelial growth factor expression in rats with sepsis

PubMed Central

LIU, MING-WEI; SU, MEI-XIAN; ZHANG, WEI; WANG, YUN HUI; QIN, LAN-FANG; LIU, XU; TIAN, MAO-LI; QIAN, CHUAN-YUN

2015-01-01

A typical indicator of sepsis is the development of progressive subcutaneous and body-cavity edema, which is caused by the breakdown of endothelial barrier function, leading to a marked increase in vascular permeability. Microvascular leakage predisposes to microvascular thrombosis, breakdown of microcirculatory flow and organ failure, which are common events preceding mortality in patients with severe sepsis. Melilotus suaveolens (M. suaveolens) is a Traditional Tibetan Medicine. Previous pharmacological studies have demonstrated that an ethanolic extract of M. suaveolens has powerful anti-inflammatory activity and leads to an improvement in capillary permeability. However, the mechanisms underlying its pharmacological activity remain elusive. The present study aimed to assess the impact of M. suaveolens extract tablets on pulmonary vascular permeability, and their effect on regulating lung inflammation and the expression of vascular endothelial growth factor (VEGF) in the lung tissue of rats with sepsis. A cecal ligation and puncture (CLP) sepsis model was established for both the control and treatment groups. ~2 h prior to surgery, 25 mg/kg of M. suaveolens extract tablet was administered to the treatment group. Polymerase chain reaction and western blot analyses were used to assess the expression of nuclear factor (NF)-κB and VEGF in the lung tissue, and ELISA was applied to detect changes in serum tumor necrosis factor-α as well as interleukins (IL) -1, -4, -6, and -10. The lung permeability, wet/dry weight ratio and lung pathology were determined. The results demonstrated that in the lung tissue of CLP-rats with sepsis, M. suaveolens extract inhibited the expression of NF-κB, reduced the inflammatory response and blocked the expression of VEGF, and thus significantly decreased lung microvascular permeability. The effects of M. Suaveolens extract may be of potential use in the treatment of CLP-mediated lung microvascular permeability. PMID:25571852

A novel culture device for the evaluation of three-dimensional extracellular matrix materials.

PubMed

Akhyari, Payam; Ziegler, Heiko; Gwanmesia, Patricia; Barth, Mareike; Schilp, Soeren; Huelsmann, Joern; Hoffmann, Stefanie; Bosch, Julia; Kögler, Gesine; Lichtenberg, Artur

2014-09-01

Cell-matrix interactions in a three-dimensional (3D) extracellular matrix (ECM) are of fundamental importance in living tissue, and their in vitro reconstruction in bioartificial structures represents a core target of contemporary tissue engineering concepts. For a detailed analysis of cell-matrix interaction under highly controlled conditions, we developed a novel ECM evaluation culture device (EECD) that allows for a precisely defined surface-seeding of 3D ECM scaffolds, irrespective of their natural geometry. The effectiveness of EECD was evaluated in the context of heart valve tissue engineering. Detergent decellularized pulmonary cusps were mounted in EECD and seeded with endothelial cells (ECs) to study EC adhesion, morphology and function on a 3D ECM after 3, 24, 48 and 96 h. Standard EC monolayers served as controls. Exclusive top-surface-seeding of 3D ECM by viable ECs was demonstrated by laser scanning microscopy (LSM), resulting in a confluent re-endothelialization of the ECM after 96 h. Cell viability and protein expression, as demonstrated by MTS assay and western blot analysis (endothelial nitric oxide synthase, von Willebrand factor), were preserved at maintained levels over time. In conclusion, EECD proves as a highly effective system for a controlled repopulation and in vitro analysis of cell-ECM interactions in 3D ECM. Copyright © 2012 John Wiley & Sons, Ltd.

Excess Visceral Adipose Tissue Worsens the Vascular Endothelial Function in Patients with Type 2 Diabetes Mellitus.

PubMed

Kurozumi, Akira; Okada, Yosuke; Arao, Tadashi; Tanaka, Yoshiya

Objective Visceral fat obesity and metabolic syndrome correlate with atherosclerosis in part due to insulin resistance and various other factors. The aim of this study was to determine the relationship between vascular endothelial dysfunction and excess visceral adipose tissue (VAT) in Japanese patients with type 2 diabetes mellitus (T2DM). Methods In 71 T2DM patients, the reactive hyperemia index (RHI) was measured using an Endo-PAT 2000, and VAT and subcutaneous adipose tissue (SAT) were measured via CT. We also measured various metabolic markers, including high-molecular-weight adiponectin (HMW-AN). Results VAT correlated negatively with the natural logarithm of RHI (L_RHI), the primary endpoint (p=0.042, r=-0.242). L_RHI did not correlate with SAT, VAT/SAT, abdominal circumference, homeostasis model assessment for insulin resistance, urinary C-peptide reactivity, HMW-AN, or alanine amino transferase, the secondary endpoints. A linear multivariate analysis via the forced entry method using age, sex, VAT, and smoking history as independent variables and L_RHI as the dependent variable revealed a lack of any determinants of L_RHI. Conclusion Excess VAT worsens the vascular endothelial function, represented by RHI which was analyzed using Endo-PAT, in Japanese patients with T2DM.

Fibrosis in connective tissue disease: the role of the myofibroblast and fibroblast-epithelial cell interactions

PubMed Central

Krieg, Thomas; Abraham, David; Lafyatis, Robert

2007-01-01

Fibrosis, characterized by excessive extracellular matrix accumulation, is a common feature of many connective tissue diseases, notably scleroderma (systemic sclerosis). Experimental studies suggest that a complex network of intercellular interactions involving endothelial cells, epithelial cells, fibroblasts and immune cells, using an array of molecular mediators, drives the pathogenic events that lead to fibrosis. Transforming growth factor-β and endothelin-1, which are part of a cytokine hierarchy with connective tissue growth factor, are key mediators of fibrogenesis and are primarily responsible for the differentiation of fibroblasts toward a myofibroblast phenotype. The tight skin mouse (Tsk-1) model of cutaneous fibrosis suggests that numerous other genes may also be important. PMID:17767742

Adipose-derived mesenchymal stromal cells from aged patients with coronary artery disease keep mesenchymal stromal cell properties but exhibit characteristics of aging and have impaired angiogenic potential.

PubMed

Efimenko, Anastasia; Dzhoyashvili, Nina; Kalinina, Natalia; Kochegura, Tatiana; Akchurin, Renat; Tkachuk, Vsevolod; Parfyonova, Yelena

2014-01-01

Tissue regeneration is impaired in aged individuals. Adipose-derived mesenchymal stromal cells (ADSCs), a promising source for cell therapy, were shown to secrete various angiogenic factors and improve vascularization of ischemic tissues. We analyzed how patient age affected the angiogenic properties of ADSCs. ADSCs were isolated from subcutaneous fat tissue of patients with coronary artery disease (CAD; n = 64, 43-77 years old) and without CAD (n = 31, 2-82 years old). ADSC phenotype characterized by flow cytometry was CD90(+)/CD73(+)/CD105(+)/CD45(-)/CD31(-) for all samples, and these cells were capable of adipogenic and osteogenic differentiation. ADSCs from aged patients had shorter telomeres (quantitative reverse transcription polymerase chain reaction) and a tendency to attenuated telomerase activity. ADSC-conditioned media (ADSC-CM) stimulated capillary-like tube formation by endothelial cells (EA.hy926), and this effect significantly decreased with the age of patients both with and without CAD. Angiogenic factors (vascular endothelial growth factor, placental growth factor, hepatocyte growth factor, angiopoetin-1, and angiogenin) in ADSC-CM measured by enzyme-linked immunosorbent assay significantly decreased with patient age, whereas levels of antiangiogenic factors thrombospondin-1 and endostatin did not. Expression of angiogenic factors in ADSCs did not change with patient age (real-time polymerase chain reaction); however, gene expression of factors related to extracellular proteolysis (urokinase and its receptor, plasminogen activator inhibitor-1) and urokinase-type plasminogen activator receptor surface expression increased in ADSCs from aged patients with CAD. ADSCs from aged patients both with and without CAD acquire aging characteristics, and their angiogenic potential declines because of decreasing proangiogenic factor secretion. This could restrict the effectiveness of autologous cell therapy with ADSCs in aged patients.

Key Features of the Intragraft Microenvironment that Determine Long-Term Survival Following Transplantation

PubMed Central

Bruneau, Sarah; Woda, Craig Bryan; Daly, Kevin Patrick; Boneschansker, Leonard; Jain, Namrata Gargee; Kochupurakkal, Nora; Contreras, Alan Gabriel; Seto, Tatsuichiro; Briscoe, David Michael

2012-01-01

In this review, we discuss how changes in the intragraft microenvironment serve to promote or sustain the development of chronic allograft rejection. We propose two key elements within the microenvironment that contribute to the rejection process. The first is endothelial cell proliferation and angiogenesis that serve to create abnormal microvascular blood flow patterns as well as local tissue hypoxia, and precedes endothelial-to-mesenchymal transition. The second is the overexpression of local cytokines and growth factors that serve to sustain inflammation and, in turn, function to promote a leukocyte-induced angiogenesis reaction. Central to both events is overexpression of vascular endothelial growth factor (VEGF), which is both pro-inflammatory and pro-angiogenic, and thus drives progression of the chronic rejection microenvironment. In our discussion, we focus on how inflammation results in angiogenesis and how leukocyte-induced angiogenesis is pathological. We also discuss how VEGF is a master control factor that fosters the development of the chronic rejection microenvironment. Overall, this review provides insight into the intragraft microenvironment as an important paradigm for future direction in the field. PMID:22566935

Changes in thrombospondin-1 levels in the endothelial cells of the anterior pituitary during estrogen-induced prolactin-secreting pituitary tumors

PubMed Central

Sarkar, Abby J; Chaturvedi, Kirti; Chen, Cui Ping; Sarkar, Dipak K

2010-01-01

Thrombospondin-1 (TSP-1), a multifunctional matrix glycoprotein, has been shown to control tumor growth by inhibiting angiogenesis in various tissues. However, the role of this glycoprotein in pituitary angiogenesis is not well studied. In this report, we determined the changes in the production and action of TSP-1 on endothelial cells in anterior pituitary following estradiol treatment, which is known to increase prolactin-secreting tumor growth and vascularization in this tissue. We showed that TSP-1 immunoreactive protein is distributed in the anterior pituitary, particularly in the endothelial cells. Estradiol treatment for 2 and 4 weeks decreased the total tissue immunoreactive level of TSP-1 as well as the endothelial cell-specific immunoreactive level of this protein in the anterior pituitary. The steroid treatment also decreased the protein levels of TSP-1 in anterior pituitary tissues and in purified pituitary endothelial cells in primary cultures. Determination of the effects of TSP-1 on proliferation and migration of pituitary-derived endothelial cells in primary cultures elucidated an inhibitory action of TSP-1 on these vascular cell functions. These results suggest that locally produced TSP-1 may regulate estrogen angiogenic action on the pituitary. PMID:17283240

Hydrogels with precisely controlled integrin activation dictate vascular patterning and permeability

NASA Astrophysics Data System (ADS)

Li, Shuoran; Nih, Lina R.; Bachman, Haylee; Fei, Peng; Li, Yilei; Nam, Eunwoo; Dimatteo, Robert; Carmichael, S. Thomas; Barker, Thomas H.; Segura, Tatiana

2017-09-01

Integrin binding to bioengineered hydrogel scaffolds is essential for tissue regrowth and regeneration, yet not all integrin binding can lead to tissue repair. Here, we show that through engineering hydrogel materials to promote α3/α5β1 integrin binding, we can promote the formation of a space-filling and mature vasculature compared with hydrogel materials that promote αvβ3 integrin binding. In vitro, α3/α5β1 scaffolds promoted endothelial cells to sprout and branch, forming organized extensive networks that eventually reached and anastomosed with neighbouring branches. In vivo, α3/α5β1 scaffolds delivering vascular endothelial growth factor (VEGF) promoted non-tortuous blood vessel formation and non-leaky blood vessels by 10 days post-stroke. In contrast, materials that promote αvβ3 integrin binding promoted endothelial sprout clumping in vitro and leaky vessels in vivo. This work shows that precisely controlled integrin activation from a biomaterial can be harnessed to direct therapeutic vessel regeneration and reduce VEGF-induced vascular permeability in vivo.

Hydrogels with precisely controlled integrin activation dictate vascular patterning and permeability

PubMed Central

Li, Shuoran; Nih, Lina R.; Bachman, Haylee; Fei, Peng; Li, Yilei; Nam, Eunwoo; Dimatteo, Robert; Carmichael, S. Thomas; Barker, Thomas H.; Segura, Tatiana

2017-01-01

Integrin binding to bioengineered hydrogel scaffolds is essential for tissue regrowth and regeneration, yet not all integrin binding can lead to tissue repair. Here, we show that through engineering hydrogel materials to promote α3/α5β1 integrin binding, we can promote the formation of a space filling and mature vasculature compared to hydrogel materials that promote a αvβ3 integrin binding. In vitro, α3/α5β1 scaffolds promoted endothelial cells to sprout and branch, forming organized extensive networks that eventually reached and anastomosed with neighboring branches. In vivo, α3/α5β1 scaffolds delivering vascular endothelial growth factor (VEGF) promoted non-tortuous blood vessel formation and non-leaky blood vessels by 10-days post stroke. In contrast, materials that promote αvβ3 integrin binding promoted endothelial sprout clumping in vitro and leaky vessels in vivo. This work shows that precisely controlled integrin activation from a biomaterial can be harnessed to direct therapeutic vessel regeneration and reduce VEGF induced vascular permeability in vivo. PMID:28783156

New insights into insulin action and resistance in the vasculature

PubMed Central

Manrique, Camila; Lastra, Guido; Sowers, James R.

2014-01-01

Two-thirds of adults in the United States are overweight or obese, and another 26 million have type 2 diabetes. Decreased insulin sensitivity in cardiovascular tissue is an underlying abnormality in these individuals. Insulin metabolic signaling increases endothelial cell nitric oxide production. Impaired vascular insulin sensitivity is an early defect leading to impaired vascular relaxation. In overweight and obese persons, as well as in those with hypertension, systemic and vascular insulin resistance often occurs in conjunction with activation of the cardiovascular tissue renin–angiotensin–aldosterone system (RAAS). Activated angiotensin II type 1 receptor and mineralocorticoid receptor signaling promote the development of vascular insulin resistance and impaired endothelial nitric oxide–mediated relaxation. Research in this area has implicated excessive serine phosphorylation and proteasomal degradation of the docking protein insulin receptor substrate and enhanced signaling through hybrid insulin/insulin-like growth factor (IGF-1) receptor as important mechanisms underlying RAAS impediment of downstream vascular insulin metabolic signaling. This review will present recent evidence supporting the notion that RAAS signaling represents a potential pathway for the development of vascular insulin resistance and impaired endothelial-mediated vasodilation. PMID:24650277

Tissue factor activity and ECM-related gene expression in human aortic endothelial cells grown on electrospun biohybrid scaffolds.

PubMed

Han, Jingjia; Gerstenhaber, Jonathan A; Lazarovici, Philip; Lelkes, Peter I

2013-05-13

All blood vessels are lined with a quiescent endothelium, which aids in regulating regular blood flow and avoiding thrombus formation. Current attempts at replacing diseased blood vessels frequently fail due to the intrinsic thrombogenicity of the materials used as vascular grafts. In extending our previous work where we introduced a new candidate scaffolds for vascular grafts electrospun from a blend solution of PLGA, gelatin, and elastin (PGE), this study aimed to evaluate the potential of PGE scaffolds to support nonthrombogenic monolayers of primary isolates of human aortic endothelial cells (HAECs), as assessed by a combination of biochemical, molecular, and bioinformatics-based analyses. After 24 h of culture on 3-D fibrous PGE scaffolds, HAECs formed a confluent, nonthrombogenic, and physiologically competent monolayer, as assessed by tissue factor (TF) gene expression and protein activity assays. The levels of TF mRNA/protein activity in HAECs grown on PGE scaffolds were similar to those on gelatin or collagen IV-coated 2-D surfaces. In addition, bioinformatics-based analysis of a focused microarray containing 84 ECM-related cDNA probes demonstrated that HAECs essentially expressed a histotypic ECM-related "transcriptome" on PGE scaffolds, where cells were more quiescent than cells cultured on 2-D coverslips coated with gelatin (a well-known "inert" substrate for conventional EC culture), but less so than on 2-D PGE films. These data suggest an important role for nanorough substrates (PGE films) in passivating endothelial cells and confirm the crucial effect of substrate composition in this process. Principal component analysis of microarray data on the above substrates (including collagen IV) implied that substrate composition plays a greater role than surface topography in affecting the endothelial ECM-related "transcriptome". Taken together, our findings suggest that electrospun PGE scaffolds are potentially suitable for application in small diameter vascular tissue engineering.

Eye Bank-Prepared Femtosecond Laser-Assisted Automated Descemet Membrane Endothelial Grafts.

PubMed

Jardine, Griffin J; Holiman, Jeffrey D; Galloway, Joshua D; Stoeger, Christopher G; Chamberlain, Winston D

2015-07-01

The aim of this study was to investigate the use of a femtosecond laser (FL) in the eye bank preparation of corneas for Descemet membrane (DM) automated endothelial keratoplasty (fDMAEK) and to compare endothelial cell death in graft preparations between fDMAEK, Descemet stripping endothelial keratoplasty (DSEK), and DM endothelial keratoplasty (DMEK). Twenty cadaveric tissues were used to test the fDMAEK method. A 9.0-mm-diameter lamellar incision was made using the FL with a 6.0-mm perpendicular anterior ring cut that enabled a stromal rim by acting as a venting incision for bubble expansion. DM was pneumodissected off the central 6.0 mm of the tissue. The fDMAEK grafts were trephined and stained with a viability dye, calcein AM. The entire stained endothelial surface was digitally captured and the endothelial cell loss (ECL) was calculated using trainable segmentation software. For comparison, a series of 6 DSEK grafts and 8 DMEK grafts were created and analyzed. Six of 20 tissues (30%) were lost during fDMAEK preparation. In the 14 successful tissues, the average ECL was 30.4% [95% confidence interval (CI), 25.3-35.6] compared with 21.1% (95% CI, 13.2-28.9, P = 0.09) in the 6 DSEK grafts and 22.5% (95% CI, 18.0-27.0, P = 0.04) in the 8 DMEK grafts. FLs are useful in preparing DMAEK tissue at the eye bank and may promote predictable and precise big bubbles and stromal rims. The fDMAEK preparation success improved with experience and laser adjustments. In fDMAEK, the ECL is higher than was previously reported in DMEK and DSEK, likely due to greater tissue manipulation, although not significantly higher than DSEK controls.

The Interactions Between Kynurenine, Folate, Methionine and Pteridine Pathways in Obesity.

PubMed

Engin, Ayse Basak; Engin, Atilla

2017-01-01

Obesity activates both innate and adaptive immune responses in adipose tissue. Elevated levels of eosinophils with depression of monocyte and neutrophil indicate the deficiencies in the immune system of morbidly obese individuals. Actually, adipose tissue macrophages are functional antigen-presenting cells that promote the proliferation of interferon-gamma (IFN-gamma)-producing CD4+ T cells in adipose tissue of obese subjects. Eventually, diet-induced obesity is associated with the loss of tissue homeostasis and development of type 1 inflammatory responses in visceral adipose tissue. Activity of inducible indoleamine 2,3-dioxygenase-1 (IDO-1) plays a major role under pro-inflammatory, IFN-gamma dominated settings. One of the two rate-limiting enzymes which can metabolize tryptophan to kynurenine is IDO-1. Tumor necrosis factor-alpha (TNF-alpha) correlates with IDO-1 in adipose compartments. Actually, IDO-1-mediated tryptophan catabolism due to chronic immune activation is the cause of reduced tryptophan plasma levels and be considered as the driving force for food intake in morbidly obese patients. Thus, decrease in plasma tryptophan levels and subsequent reduction in serotonin (5-HT) production provokes satiety dysregulation that leads to increased caloric uptake and obesity. However, after bariatric surgery, weight reduction does not lead to normalization of IDO-1 activity. Furthermore, there is a connection between arginine and tryptophan metabolic pathways in the generation of reactive nitrogen intermediates. Hence, abdominal obesity is associated with vascular endothelial dysfunction and reduced nitric oxide (NO) availability. IFN-gamma-induced activation of the inducible nitric oxide synthase (iNOS) and dissociation of endothelial adenosine monophosphate activated protein kinase (AMPK)- phosphoinositide 3-kinase (PI3K)-protein kinase B (Akt)- endothelial NO synthase (eNOS) pathway enhances oxidative stress production secondary to high-fat diet. Thus, reduced endothelial NO availability correlates with the increase in plasma non-esterified fatty acids and triglycerides levels. Additionally, in obese patients, folate-deficiency leads to hyperhomocysteinemia. Folic acid confers protection against hyperhomocysteinemia-induced oxidative stress.

Combined chemical and structural signals of biomaterials synergistically activate cell-cell communications for improving tissue regeneration.

PubMed

Xu, Yachen; Peng, Jinliang; Dong, Xin; Xu, Yuhong; Li, Haiyan; Chang, Jiang

2017-06-01

Biomaterials are only used as carriers of cells in the conventional tissue engineering. Considering the multi-cell environment and active cell-biomaterial interactions in tissue regeneration process, in this study, structural signals of aligned electrospun nanofibers and chemical signals of bioglass (BG) ionic products in cell culture medium are simultaneously applied to activate fibroblast-endothelial co-cultured cells in order to obtain an improved skin tissue engineering construct. Results demonstrate that the combined biomaterial signals synergistically activate fibroblast-endothelial co-culture skin tissue engineering constructs through promotion of paracrine effects and stimulation of gap junctional communication between cells, which results in enhanced vascularization and extracellular matrix protein synthesis in the constructs. Structural signals of aligned electrospun nanofibers play an important role in stimulating both of paracrine and gap junctional communication while chemical signals of BG ionic products mainly enhance paracrine effects. In vivo experiments reveal that the activated skin tissue engineering constructs significantly enhance wound healing as compared to control. This study indicates the advantages of synergistic effects between different bioactive signals of biomaterials can be taken to activate communication between different types of cells for obtaining tissue engineering constructs with improved functions. Tissue engineering can regenerate or replace tissue or organs through combining cells, biomaterials and growth factors. Normally, for repairing a specific tissue, only one type of cells, one kind of biomaterials, and specific growth factors are used to support cell growth. In this study, we proposed a novel tissue engineering approach by simply using co-cultured cells and combined biomaterial signals. Using a skin tissue engineering model, we successfully proved that the combined biomaterial signals such as surface nanostructures and bioactive ions could synergistically stimulate the cell-cell communication in co-culture system through paracrine effects and gap junction activation, and regulated expression of growth factors and extracellular matrix proteins, resulting in an activated tissue engineering constructs that significantly enhanced skin regeneration. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Mechanical Stretching Promotes Skin Tissue Regeneration via Enhancing Mesenchymal Stem Cell Homing and Transdifferentiation.

PubMed

Liang, Xiao; Huang, Xiaolu; Zhou, Yiwen; Jin, Rui; Li, Qingfeng

2016-07-01

Skin tissue expansion is a clinical procedure for skin regeneration to reconstruct cutaneous defects that can be accompanied by severe complications. The transplantation of mesenchymal stem cells (MSCs) has been proven effective in promoting skin expansion and helping to ameliorate complications; however, systematic understanding of its mechanism remains unclear. MSCs from luciferase-Tg Lewis rats were intravenously transplanted into a rat tissue expansion model to identify homing and transdifferentiation. To clarify underlying mechanisms, a systematic approach was used to identify the differentially expressed genes between mechanically stretched human MSCs and controls. The biological significance of these changes was analyzed through bioinformatic methods. We further investigated genes and pathways of interest to disclose their potential role in mechanical stretching-induced skin regeneration. Cross sections of skin samples from the expanded group showed significantly more luciferase(+) and stromal cell-derived factor 1α (SDF-1α)(+), luciferase(+)keratin 14(+), and luciferase(+)CD31(+) cells than the control group, indicating MSC transdifferentiation into epidermal basal cells and endothelial cells after SDF-1α-mediated homing. Microarray analysis suggested upregulation of genes related to hypoxia, vascularization, and cell proliferation in the stretched human MSCs. Further investigation showed that the homing of MSCs was blocked by short interfering RNA targeted against matrix metalloproteinase 2, and that mechanical stretching-induced vascular endothelial growth factor A upregulation was related to the Janus kinase/signal transducer and activator of transcription (Jak-STAT) and Wnt signaling pathways. This study determines that mechanical stretching might promote skin regeneration by upregulating MSC expression of genes related to hypoxia, vascularization, and cell proliferation; enhancing transplanted MSC homing to the expanded skin; and transdifferentiation into epidermal basal cells and endothelial cells. Skin tissue expansion is a clinical procedure for skin regeneration to cover cutaneous defects that can be accompanied by severe complications. The transplantation of mesenchymal stem cells (MSCs) has been proven effective in promoting skin expansion and ameliorating complications. This study, which sought to provide a systematic understanding of the mechanism, determined that mechanical stretching could upregulate MSC expression of genes related to hypoxia, vascularization, and cell proliferation; enhance transplanted MSC homing to the expanded skin tissue; and promote their transdifferentiation into epidermal basal cells and endothelial cells. ©AlphaMed Press.

Human iPS cell-engineered cardiac tissue sheets with cardiomyocytes and vascular cells for cardiac regeneration

PubMed Central

Masumoto, Hidetoshi; Ikuno, Takeshi; Takeda, Masafumi; Fukushima, Hiroyuki; Marui, Akira; Katayama, Shiori; Shimizu, Tatsuya; Ikeda, Tadashi; Okano, Teruo; Sakata, Ryuzo; Yamashita, Jun K.

2014-01-01

To realize cardiac regeneration using human induced pluripotent stem cells (hiPSCs), strategies for cell preparation, tissue engineering and transplantation must be explored. Here we report a new protocol for the simultaneous induction of cardiomyocytes (CMs) and vascular cells [endothelial cells (ECs)/vascular mural cells (MCs)], and generate entirely hiPSC-engineered cardiovascular cell sheets, which showed advantageous therapeutic effects in infarcted hearts. The protocol adds to a previous differentiation protocol of CMs by using stage-specific supplementation of vascular endothelial cell growth factor for the additional induction of vascular cells. Using this cell sheet technology, we successfully generated physically integrated cardiac tissue sheets (hiPSC-CTSs). HiPSC-CTS transplantation to rat infarcted hearts significantly improved cardiac function. In addition to neovascularization, we confirmed that engrafted human cells mainly consisted of CMs in >40% of transplanted rats four weeks after transplantation. Thus, our HiPSC-CTSs show promise for cardiac regenerative therapy. PMID:25336194

Trophic factors from adipose tissue-derived multi-lineage progenitor cells promote cytodifferentiation of periodontal ligament cells.

PubMed

Sawada, Keigo; Takedachi, Masahide; Yamamoto, Satomi; Morimoto, Chiaki; Ozasa, Masao; Iwayama, Tomoaki; Lee, Chun Man; Okura, Hanayuki; Matsuyama, Akifumi; Kitamura, Masahiro; Murakami, Shinya

2015-08-14

Stem and progenitor cells are currently being investigated for their applicability in cell-based therapy for periodontal tissue regeneration. We recently demonstrated that the transplantation of adipose tissue-derived multi-lineage progenitor cells (ADMPCs) enhances periodontal tissue regeneration in beagle dogs. However, the molecular mechanisms by which transplanted ADMPCs induce periodontal tissue regeneration remain to be elucidated. In this study, trophic factors released by ADMPCs were examined for their paracrine effects on human periodontal ligament cell (HPDL) function. ADMPC conditioned medium (ADMPC-CM) up-regulated osteoblastic gene expression, alkaline phosphatase activity and calcified nodule formation in HPDLs, but did not significantly affect their proliferative response. ADMPCs secreted a number of growth factors, including insulin-like growth factor binding protein 6 (IGFBP6), hepatocyte growth factor and vascular endothelial growth factor. Among these, IGFBP6 was most highly expressed. Interestingly, the positive effects of ADMPC-CM on HPDL differentiation were significantly suppressed by transfecting ADMPCs with IGFBP6 siRNA. Our results suggest that ADMPCs transplanted into a defect in periodontal tissue release trophic factors that can stimulate the differentiation of HPDLs to mineralized tissue-forming cells, such as osteoblasts and cementoblasts. IGFBP6 may play crucial roles in ADMPC-induced periodontal regeneration. Copyright © 2015 Elsevier Inc. All rights reserved.

Expression of vascular endothelial growth factor in Juvenile Angiofibroma.

PubMed

Hota, Ashutosh; Sarkar, Chitra; Gupta, Siddhartha Datta; Kumar, Rakesh; Bhalla, Ashu Seith; Thakar, Alok

2015-06-01

To examine Juvenile Angiofibroma (JA) tissue for expression of vascular endothelial growth factor (VEGF), and to explore its relationship with puberty status, stage, recurrence and the intraoperative blood loss. Retrospective cohort study of 36 histologically proven cases of JA. Minimum follow up period was 3 years. VEGF expression on tumor cells assessed by immunohistochemistry and graded on two criteria--percentage of cells expressing positivity and the intensity of positivity. These two parameters assessed for impact on puberty status, stage, recurrence, and blood loss. VEGF expression noted on the tumor endothelial cells in 36/36, and on the tumor stromal cells in 34/36. The percentage of cells expressing VEGF and the intensity of expression were not significantly related to puberty status, tumor stage, recurrence, or intra-operative blood loss (p values 0.3-1.0). VEGF expression is near universal in JA. Such expression is independent of puberty status and stage, and does not impact on intra operative blood loss and recurrence. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Therapeutic potential of ixmyelocel-T, an expanded autologous multicellular therapy for treatment of ischemic cardiovascular diseases.

PubMed

Ledford, Kelly J; Murphy, Nikki; Zeigler, Frank; Bartel, Ronnda L; Tubo, Ross

2015-03-13

Bone marrow derived cellular therapies are an emerging approach to promoting therapeutic angiogenesis in ischemic cardiovascular disease. However, the percentage of regenerative cells in bone marrow mononuclear cells (BMMNCs) is small, and large amounts of BMMNCs are required. Ixmyelocel-T, an expanded autologous multicellular therapy, is manufactured from a small sample of bone marrow aspirate. Ixmyelocel-T contains expanded populations of mesenchymal stromal cells (MSCs) and M2-like macrophages, as well as many of the CD45+ cells found in the bone marrow. It is hypothesized that this expanded multi-cellular therapy would induce angiogenesis and endothelial repair. A rat model of hind limb ischemia was used to determine the effects of ixmyelocel-T on blood flow recovery. To further determine the effects on endothelial cells, ixmyelocel-T was co-cultured with human umbilical vein endothelial cells (HUVEC) in non-contacting Transwell® inserts. Co-culture of HUVECs with ixmyelocel-T resulted secretion of a variety of pro-angiogenic factors. HUVECs stimulated by ixmyelocel-T exhibited enhanced migration, proliferation, and branch formation. Ixmyelocel-T co-culture also resulted in increased endothelial nitric oxide synthase (eNOS) expression and nitric oxide (NO) production. In tumor necrosis factor alpha (TNFα)-stimulated HUVECs, ixmyelocel-T co-culture decreased apoptosis and reactive oxygen species generation, increased super oxide dismutase activity, and decreased nuclear factor kappa B (NFκB) activation. Treatment with ixmyelocel-T in a rat model of hind limb ischemia resulted in significantly increased blood flow perfusion and capillary density, gene expression and plasma levels of the anti-inflammatory cytokine interleukin (IL)-10, plasma nitrates, plasma platelet-derived growth factor (PDGF)-BB, vascular endothelial growth factor (VEGF) expression, and significantly decreased plasma thiobarbituric acid reactive substances (TBARS). This work demonstrates that ixmyelocel-T interacts with endothelial cells in a paracrine manner, resulting in angiogenesis and endothelial protection. This data suggests that ixmyelocel-T could be useful for promoting of angiogenesis and tissue repair in ischemic cardiovascular diseases. In conclusion, ixmyelocel-T therapy may provide a new aspect of therapeutic angiogenesis in this patient population where expanded populations of regenerative cells might be required.

Adipose Tissue as an Endocrine Organ: An Update on Pro-inflammatory and Anti-inflammatory Microenvironment.

PubMed

Smitka, Kvido; Marešová, Dana

2015-01-01

Adipose tissue is recognized as an active endocrine organ that produces a number of endocrine substances referred to as "adipokines" including leptin, adiponectin, adipolin, visfatin, omentin, tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), resistin, pigment epithelium-derived factor (PEDF), and progranulin (PGRN) which play an important role in the food intake regulation and significantly influence insulin sensitivity and in some cases directly affect insulin resistance in skeletal muscle, liver, and adipose tissue. The review summarizes current knowledge about adipose tissue-derived hormones and their influence on energy homeostasis regulation. The possible therapeutic potential of these adipokines in the treatment of insulin resistance, endothelial dysfunction, a pro-inflammatory response, obesity, eating disorders, progression of atherosclerosis, type 1 diabetes, and type 2 diabetes is discussed.

The Interaction Between IGF-1, Atherosclerosis and Vascular Aging

PubMed Central

Higashi, Yusuke; Quevedo, Henry C.; Tiwari, Summit; Sukhanov, Sergiy; Shai, Shaw-Yung; Anwar, Asif; Delafontaine, Patrice

2014-01-01

The process of vascular aging encompasses alterations in the function of endothelial (EC) and vascular smooth muscle cells (VSMCs) via oxidation, inflammation, cell senescence and epigenetic modifications, increasing the probability of atherosclerosis. Aged vessels exhibit decreased endothelial antithrombogenic properties, increased reactive oxygen species (ROS) generation and inflammatory signaling, increased migration of VSMCs to the subintimal space, impaired angiogenesis and increased elastin degradation. The key initiating step in atherogenesis is subendothelial accumulation of apolipoprotein-B containing low density lipoproteins resulting in activation of endothelial cells and recruitment of monocytes. Activated endothelial cells secrete “chemokines” that interact with cognate chemokine receptors on monocytes and promote directional migration. Recruitment of immune cells establishes a pro-inflammatory status, further causing elevated oxidative stress, which in turn triggers a series of events including apoptotic or necrotic death of vascular and non-vascular cells. Increased oxidative stress is also considered to be a key factor in mechanisms of aging-associated changes in tissue integrity and function. Experimental evidence indicates that insulin-like growth factor-1 (IGF-1) exerts anti-oxidant, anti-inflammatory and pro-survival effects on the vasculature, reducing atherosclerotic plaque burden and promoting features of atherosclerotic plaque stability. PMID:24943302

Label-free assessment of endothelial cell metabolic state using autofluorescent microscopy

NASA Astrophysics Data System (ADS)

Pullen, Benjamin J.; Nguyen, Tam; Gosnell, Martin; Anwer, Ayad G.; Goldys, Ewa; Nicholls, Stephen J.; Psaltis, Peter J.

2016-12-01

To examine the process of endothelial cell aging we utilised hyperspectral imaging to collect broad autofluorescence emission at the individual cellular level and mathematically isolate the characteristic spectra of nicotinamide and flavin adenine dinucleotides (NADH and FAD, respectively). Quantitative analysis of this data provides the basis for a non-destructive spatial imaging method for cells and tissue. FAD and NADH are important factors in cellular metabolism and have been shown to be involved with the redox state of the cell; with the ratio between the two providing the basis for an `optical redox ratio'.

Angiogenesis and expression of vascular endothelial growth factor, tumour necrosis factor-α and hypoxia inducible factor-1α in canine renal cell carcinoma.

PubMed

Yhee, J Y; Yu, C H; Kim, J H; Im, K S; Kim, N H; Brodersen, B W; Doster, A R; Sur, J-H

2012-01-01

The aim of the present study was to determine the distribution and characteristics of microvessels in various histological types of canine renal cell carcinoma (RCC). The study compared microvessel density (MVD) and distribution of blood vessels according to histological type and evaluated the presence of angiogenesis-related proteins. Nine archival samples of canine RCC were studied. MVD was calculated as the mean number of blood vessels per mm(2). The diameter of blood vessels was calculated by determining either the length of the long axis of blood vessels (diameter(max)) or the mean distance from the centre of each blood vessel to the tunica adventia (diameter(mean)). A significant difference in MVD was evident between RCCs and normal kidneys (46.6 ± 28.0 versus 8.4 ± 2.2 microvessels/mm(2)). Diameter(max) in canine RCCs (34.1 ± 14.7 μm) was also significantly different from normal canine kidney (23.2 ± 3.4 μm). Vascular endothelial growth factor (VEGF) was expressed by tumour cells and vascular endothelial cells and tumour necrosis factor (TNF)-α expression was observed in vascular endothelial cells in both neoplastic and normal kidney. Although VEGF is involved in angiogenesis and correlates with tumour stage of development, no correlation was found between VEGF expression and MVD. Tumour-associated macrophages expressing TNF-α and hypoxia inducible factor 1α were identified in peritumoural tissue and may play an important role in angiogenesis. Copyright © 2011 Elsevier Ltd. All rights reserved.

Expression of Vascular Endothelial Growth Factor in Odontogenic Cysts: Is There Any Impression on Clinical Outcome?

PubMed

Sadri, Donia; Farhadi, Sareh; Shahabi, Zahra; Sarshar, Samaneh

2016-01-01

The recent scientific reports have shown that angiogenesis can affect biological behavior of pathologic lesions. Regarding unique clinical outcome of Odontogenic keratocyst (OKC), the present study was aimed to compare angiogenesis in Odontogenic keratocyst and Dentigerous cyst (DC). In this experimental study, tissue sections of 46 samples of OKC and DC were stained through immunohistochemical method using Vascular Endothelial Growth Factor (VEGF) antibody. VEGF expression was evaluated in epithelial cells, fibroblasts and endothelial cells. The average percentage of stained cells in any samples was categorized to 3 groups as follows: SCORE 0: 10% of cells or less are positive. SCORE 1: 10 to 50% of cells are positive. SCORE 2: more than 50% of cells are positive. Mann-U-Whitney, T-test and chi-square was used for statistical analysis. The average of VEGF expression in 24 samples of DC was 20.2% and in 22 samples of OKC was 52.6%, respectively. The average of VEGF expression in these two cysts had statistical significant differences. (PV= 0.045). There was significant statistical differences between two cysts in the terms of VEGF SCORE (PV= 0.000). OKC samples had significantly higher SCORE for the purpose of VEGF incidence than DC. Also, there were no differences between VEGF expression in epithelial cells of two cysts (PV= 0.268) there were significant statistical differences between two cysts in terms of endothelial cell staining. The endothelial cell staining was significantly higher in OKC than DC (PV= 0.037%). Regarding higher expression of Vascular Endothelial Growth factor in OKC than DC, it seems that angiogenesis may have great impression on clinical outcome of OKC.

Validation of an endothelial roll preparation for Descemet Membrane Endothelial Keratoplasty by a cornea bank using "no touch" dissection technique.

PubMed

Marty, Anne-Sophie; Burillon, Carole; Desanlis, Adeline; Damour, Odile; Kocaba, Viridiana; Auxenfans, Céline

2016-06-01

Descemet Membrane Endothelial Keratoplasty (DMEK) selectively replaces the damaged posterior part of the cornea. However, the DMEK technique relies on a manually-performed dissection that is time-consuming, requires training and presents a potential risk of endothelial graft damages leading to surgery postponement when performed by surgeons in the operative room. To validate precut corneal tissue preparation for DMEK provided by a cornea bank in order to supply a quality and security precut endothelial tissue. The protocol was a technology transfer from the Netherlands Institute for Innovative Ocular Surgery (NIIOS) to Lyon Cornea Bank, after formation in NIIOS to the DMEK "no touch" dissection technique. The technique has been validated in selected conditions (materials, microscope) and after a learning curve, cornea bank technicians prepared endothelial tissue for DMEK. Endothelial cells densities (ECD) were evaluated before and after preparation, after storage and transport to the surgery room. Microbiological and histological controls have been done. Twenty corneas were manually dissected; 18 without tears. Nineteen endothelial grafts formed a double roll. The ECD loss after cutting was 3.3 % (n = 19). After transportation 7 days later, we found an ECD loss of 25 % (n = 12). Three days after cutting and transportation, we found 2.1 % of ECD loss (n = 7). Histology found an endothelial cells monolayer lying on Descemet membrane. The mean thickness was 12 ± 2.2 µm (n = 4). No microbial contamination was found (n = 19). Endothelial roll stability has been validated at 3 days in our cornea bank. Cornea bank technicians trained can deliver to surgeons an ECD controlled, safety and ready to use endothelial tissue, for DMEK by "no touch" technique, allowing time saving, quality and security for surgeons.

Vascular endothelial growth factor and platelet-derived growth factor are potential angiogenic and metastatic factors in human breast cancer.

PubMed

Anan, K; Morisaki, T; Katano, M; Ikubo, A; Kitsuki, H; Uchiyama, A; Kuroki, S; Tanaka, M; Torisu, M

1996-03-01

Angiogenesis is a prerequisite for tumor growth and metastasis. Tumor angiogenesis may be mediated by several angiogenic factors such as vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), transforming growth factor-alpha, and basic fibroblast growth factor. Differential mRNA expressions of VEGF, PDGF (A chain), transforming growth factor-alpha and basic fibroblast growth factor in 32 primary invasive breast tumors were examined by reverse transcriptase-polymerase chain reaction. We analyzed relationships between mRNA expressions of these angiogenic factors and the degree of angiogenesis, tumor size, and metastasis. Quantification of angiogenesis was achieved by the immunohistochemical staining of endothelial cells with antibody to CD31. VEGF and PDGF-A mRNAs were expressed more frequently in breast tumors than in nontumor breast tissues, whereas no difference was found in expression frequency of either transforming growth factor-alpha or basic fibroblast growth factor mRNA. Vascular counts in tumors correlated with each expression frequency of VEGF and PDGF-A mRNA. PDGF-A mRNA was expressed more frequently in tumors with lymph node metastasis than in those without metastasis. Expression of VEGF and PDGF mRNAs detected by reverse transcriptase-polymerase chain reaction in breast tumors correlates with tumor-related characteristics of angiogenesis and metastatic potential. Analysis of these mRNAs by reverse transcriptase-polymerase chain reaction may be useful for assessing the biologic behavior of a breast tumor before surgical treatment.

Dual ECM Biomimetic Scaffolds for Dental Pulp Regenerative Applications

PubMed Central

Huang, Chun-Chieh; Narayanan, Raghuvaran; Warshawsky, Noah; Ravindran, Sriram

2018-01-01

Dental pulp is a highly vascularized and innervated tissue that provides sensitivity and vitality to the tooth. Chronic caries results in an infected pulp tissue prone to necrosis. Existing clinical treatments replace the living pulp tissue with a non-responsive resin filling resulting in loss of tooth vitality. Tissue engineering approaches to dental pulp tissue regeneration have been investigated to preserve tooth vitality and function. However, a critical criterion is the choice of growth factors that may promote mesenchymal stem cell differentiation and more importantly, vascularization. But, the problems associated with growth factor dosage, delivery, safety, immunological and ectopic complications affect their translatory potential severely. The purpose of this study is to develop, characterize and evaluate a biomimetic native extracellular matrix (ECM) derived dual ECM scaffold that consists of a pulp-specific ECM to promote MSC attachment, proliferation and differentiation and an endothelial ECM to promote migration of host endothelial cells and eventual vascularization in vivo. Our results show that the dual ECM scaffolds possess similar properties as a pulp-ECM scaffold to promote MSC attachment and odontogenic differentiation in vitro. Additionally, when implanted subcutaneously in a tooth root slice model in vivo, the dual ECM scaffolds promoted robust odontogenic differentiation of both dental pulp and bone marrow derived MSCs and also extensive vascularization when compared to respective controls. These scaffolds are mass producible for clinical use and hence have the potential to replace root canal therapy as a treatment for chronic dental caries. PMID:29887803

Angiogenic mechanisms of human dental pulp and their relationship with substance P expression in response to occlusal trauma.

PubMed

Caviedes-Bucheli, J; Gomez-Sosa, J F; Azuero-Holguin, M M; Ormeño-Gomez, M; Pinto-Pascual, V; Munoz, H R

2017-04-01

Angiogenesis is the formation of new blood vessels based on a pre-existing vasculature. It comprises two processes, sprouting of endothelial cells and the division of vessels due to abnormal growth of the microvasculature. It has been demonstrated that substance P (SP) can induce angiogenesis either by modulating endothelial cell growth (direct mechanism) or by attracting cells with angiogenic potential to the injury site (indirect mechanism). Therefore, the purpose of this article is to review the angiogenic mechanisms that regulate mineralized tissue formation in human dental pulp tissue and their relationship with SP expression as a defence response to stimuli such as the masticatory function and occlusal trauma. Articles included in this review were searched in PubMed, Scopus and ISI Web of Science databases, combining the following keywords: human dentine pulp, angiogenesis, angiogenic growth factors, neuropeptides, substance P, neurogenic inflammation, dentine matrix, dentinogenesis, occlusal trauma and dental occlusion. It is concluded that human dental pulp tissue responds to occlusal trauma and masticatory function with a neurogenic inflammatory phenomenon in which SP plays an important role in the direct and indirect mechanisms of angiogenesis by the action evoked via NK1 receptors at different cells, such as fibroblasts, endothelial and inflammatory cells, leading to new blood vessel formation which are needed to stimulate mineralized tissue formation as a defence mechanism. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Inflammatory Mediators and Angiogenic Factors in Choroidal Neovascularization: Pathogenetic Interactions and Therapeutic Implications

PubMed Central

Campa, Claudio; Costagliola, Ciro; Incorvaia, Carlo; Sheridan, Carl; Semeraro, Francesco; De Nadai, Katia; Sebastiani, Adolfo; Parmeggiani, Francesco

2010-01-01

Choroidal neovascularization (CNV) is a common and severe complication in heterogeneous diseases affecting the posterior segment of the eye, the most frequent being represented by age-related macular degeneration. Although the term may suggest just a vascular pathological condition, CNV is more properly definable as an aberrant tissue invasion of endothelial and inflammatory cells, in which both angiogenesis and inflammation are involved. Experimental and clinical evidences show that vascular endothelial growth factor is a key signal in promoting angiogenesis. However, many other molecules, distinctive of the inflammatory response, act as neovascular activators in CNV. These include fibroblast growth factor, transforming growth factor, tumor necrosis factor, interleukins, and complement. This paper reviews the role of inflammatory mediators and angiogenic factors in the development of CNV, proposing pathogenetic assumptions of mutual interaction. As an extension of this concept, new therapeutic approaches geared to have an effect on both the vascular and the extravascular components of CNV are discussed. PMID:20871825

Scaffold Composition Determines the Angiogenic Outcome of Cell-Based Vascular Endothelial Growth Factor Expression by Modulating Its Microenvironmental Distribution.

PubMed

Gaudiello, Emanuele; Melly, Ludovic; Cerino, Giulia; Boccardo, Stefano; Jalili-Firoozinezhad, Sasan; Xu, Lifen; Eckstein, Friedrich; Martin, Ivan; Kaufmann, Beat A; Banfi, Andrea; Marsano, Anna

2017-12-01

Delivery of genetically modified cells overexpressing Vascular Endothelial Growth Factor (VEGF) is a promising approach to induce therapeutic angiogenesis in ischemic tissues. The effect of the protein is strictly modulated by its interaction with the components of the extracellular matrix. Its therapeutic potential depends on a sustained but controlled release at the microenvironmental level in order to avoid the formation of abnormal blood vessels. In this study, it is hypothesized that the composition of the scaffold plays a key role in modulating the binding, hence the therapeutic effect, of the VEGF released by 3D-cell constructs. It is found that collagen sponges, which poorly bind VEGF, prevent the formation of localized hot spots of excessive concentration, therefore, precluding the development of aberrant angiogenesis despite uncontrolled expression by a genetically engineered population of adipose tissue-derived stromal cells. On the contrary, after seeding on VEGF-binding egg-white scaffolds, the same cell population caused aberrantly enlarged vascular structures after 14 d. Collagen-based engineered tissues also induced a safe and efficient angiogenesis in both the patch itself and the underlying myocardium in rat models. These findings open new perspectives on the control and the delivery of proangiogenic stimuli, and are fundamental for the vascularization of engineered tissues/organs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Secretomes from bone marrow-derived mesenchymal stromal cells enhance periodontal tissue regeneration.

PubMed

Kawai, Takamasa; Katagiri, Wataru; Osugi, Masashi; Sugimura, Yukiko; Hibi, Hideharu; Ueda, Minoru

2015-04-01

Periodontal tissue regeneration with the use of mesenchymal stromal cells (MSCs) has been regarded as a future cell-based therapy. However, low survival rates and the potential tumorigenicity of implanted MSCs could undermine the efficacy of cell-based therapy. The use of conditioned media from MSCs (MSC-CM) may be a feasible approach to overcome these limitations. The aim of this study was to confirm the effect of MSC-CM on periodontal regeneration. MSC-CM were collected during their cultivation. The concentrations of the growth factors in MSC-CM were measured with the use of enzyme-linked immunoassay. Rat MSCs (rMSCs) and human umbilical vein endothelial cells cultured in MSC-CM were assessed on wound-healing and angiogenesis. The expressions of osteogenetic- and angiogenic-related genes of rMSCs cultured in MSC-CM were quantified by means of real-time reverse transcriptase-polymerase chain reaction analysis. In vivo, periodontal defects were prepared in the rat models and the collagen sponges with MSC-CM were implanted. MSC-CM includes insulin-like growth factor-1, vascular endothelial growth factor, transforming growth factor-β1 and hepatocyte growth factor. In vitro, wound-healing and angiogenesis increased significantly in MSC-CM. The levels of expression of osteogenetic- and angiogenic-related genes were significantly upregulated in rMSCs cultured with MSC-CM. In vivo, in the MSC-CM group, 2 weeks after implantation, immunohistochemical analysis showed several CD31-, CD105-or FLK-1-positive cells occurring frequently. At 4 weeks after implantation, regenerated periodontal tissue was observed in MSC-CM groups. The use of MSC-CM may be an alternative therapy for periodontal tissue regeneration because several cytokines included in MSC-CM will contribute to many processes of complicated periodontal tissue regeneration. Copyright © 2015 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Gastrin-releasing peptide induces monocyte adhesion to vascular endothelium by upregulating endothelial adhesion molecules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Mi-Kyoung; Park, Hyun-Joo; Department of Dental Pharmacology, BK21 PLUS Project, School of Dentistry, Pusan National University, Yangsan 626-870

Gastrin-releasing peptide (GRP) is a neuropeptide that plays roles in various pathophysiological conditions including inflammatory diseases in peripheral tissues; however, little is known about whether GRP can directly regulate endothelial inflammatory processes. In this study, we showed that GRP promotes the adhesion of leukocytes to human umbilical vein endothelial cells (HUVECs) and the aortic endothelium. GRP increased the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) by activating nuclear factor-κB (NF-κB) in endothelial cells. In addition, GRP activated extracellular signal-regulated kinase 1/2 (ERK1/2), p38MAPK, and AKT, and the inhibition of these signaling pathways significantly reduced GRP-inducedmore » monocyte adhesion to the endothelium. Overall, our results suggested that GRP may cause endothelial dysfunction, which could be of particular relevance in the development of vascular inflammatory disorders. - Highlights: • GRP induces adhesion of monocytes to vascular endothelium. • GRP increases the expression of endothelial adhesion molecules through the activation of NF-κB. • ERK1/2, p38MAPK, and Akt pathways are involved in the GRP-induced leukocyte adhesiveness to endothelium.« less

Scleroderma Related Lung Disease: Is There a Pathogenic Role for Adipokines?

PubMed Central

Haley, Shannon; Shah, Dilip; Romero, Freddy; Summer, Ross

2013-01-01

Scleroderma is a systemic autoimmune disease of unknown etiology whose hallmark features include endothelial cell dysfunction, fibroblast proliferation and immune dysregulation. Although virtually any organ can be pathologically involved in scleroderma, lung complications including interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH) are the leading cause of death in patients with this condition. Currently, the molecular mechanisms leading to development of scleroderma-related lung disease are poorly understood; however, the systemic nature of this condition has led many to implicate circulating factors in the pathogenesis of some of its organ impairment. In this article, we focus on a new class of circulating factors derived from adipose-tissue called adipokines, which are known to be altered in scleroderma. Recently, the adipokines adiponectin and leptin have been found to regulate biological activities in endothelial, fibroblast and immune cell types in lung and in many other tissues. The pleiotropic nature of these circulating factors and their functional activity on many cell types implicated in the pathogenesis of ILD and PAH suggest these hormones may play a mechanistic role in the onset and/or progression of scleroderma-related lung diseases. PMID:24173692

Effects of exercise training on chronic inflammation in obesity : current evidence and potential mechanisms.

PubMed

You, Tongjian; Arsenis, Nicole C; Disanzo, Beth L; Lamonte, Michael J

2013-04-01

Chronic, systemic inflammation is an independent risk factor for several major clinical diseases. In obesity, circulating levels of inflammatory markers are elevated, possibly due to increased production of pro-inflammatory cytokines from several tissues/cells, including macrophages within adipose tissue, vascular endothelial cells and peripheral blood mononuclear cells. Recent evidence supports that adipose tissue hypoxia may be an important mechanism through which enlarged adipose tissue elicits local tissue inflammation and further contributes to systemic inflammation. Current evidence supports that exercise training, such as aerobic and resistance exercise, reduces chronic inflammation, especially in obese individuals with high levels of inflammatory biomarkers undergoing a longer-term intervention. Several studies have reported that this effect is independent of the exercise-induced weight loss. There are several mechanisms through which exercise training reduces chronic inflammation, including its effect on muscle tissue to generate muscle-derived, anti-inflammatory 'myokine', its effect on adipose tissue to improve hypoxia and reduce local adipose tissue inflammation, its effect on endothelial cells to reduce leukocyte adhesion and cytokine production systemically, and its effect on the immune system to lower the number of pro-inflammatory cells and reduce pro-inflammatory cytokine production per cell. Of these potential mechanisms, the effect of exercise training on adipose tissue oxygenation is worth further investigation, as it is very likely that exercise training stimulates adipose tissue angiogenesis and increases blood flow, thereby reducing hypoxia and the associated chronic inflammation in adipose tissue of obese individuals.

Targeting vascular (endothelial) dysfunction

PubMed Central

Steven, Sebastian; Weber, Alina; Shuvaev, Vladimir V.; Muzykantov, Vladimir R.; Laher, Ismail; Li, Huige; Lamas, Santiago

2016-01-01

Abstract Cardiovascular diseases are major contributors to global deaths and disability‐adjusted life years, with hypertension a significant risk factor for all causes of death. The endothelium that lines the inner wall of the vasculature regulates essential haemostatic functions, such as vascular tone, circulation of blood cells, inflammation and platelet activity. Endothelial dysfunction is an early predictor of atherosclerosis and future cardiovascular events. We review the prognostic value of obtaining measurements of endothelial function, the clinical techniques for its determination, the mechanisms leading to endothelial dysfunction and the therapeutic treatment of endothelial dysfunction. Since vascular oxidative stress and inflammation are major determinants of endothelial function, we have also addressed current antioxidant and anti‐inflammatory therapies. In the light of recent data that dispute the prognostic value of endothelial function in healthy human cohorts, we also discuss alternative diagnostic parameters such as vascular stiffness index and intima/media thickness ratio. We also suggest that assessing vascular function, including that of smooth muscle and even perivascular adipose tissue, may be an appropriate parameter for clinical investigations. Linked Articles This article is part of a themed section on Redox Biology and Oxidative Stress in Health and Disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.12/issuetoc PMID:27187006

Mechanisms of Angiogenesis and Lymphangiogenesis in TSC Skin Tumors

DTIC Science & Technology

2011-09-16

associated macrophage PKD Polycystic kidney disease TGF-β Transforming growth factor-β pS6 Phospho ribosomal protein S6 TNF-α Tumor necrosis factor...blood supply. They are found in the skin and other tissues except the central nervous system, bone marrow and avascular structures including epidermis...273:8413-8418 232. Cha HS, Bae EK, Koh JH, Chai JY, Jeon CH, Ahn KS, Kim J, Koh EM: Tumor necrosis factor-alpha induces vascular endothelial

Platelet lysate-based pro-angiogenic nanocoatings.

PubMed

Oliveira, Sara M; Pirraco, Rogério P; Marques, Alexandra P; Santo, Vítor E; Gomes, Manuela E; Reis, Rui L; Mano, João F

2016-03-01

Human platelet lysate (PL) is a cost-effective and human source of autologous multiple and potent pro-angiogenic factors, such as vascular endothelial growth factor A (VEGF A), fibroblast growth factor b (FGF b) and angiopoietin-1. Nanocoatings previously characterized were prepared by layer-by-layer assembling incorporating PL with marine-origin polysaccharides and were shown to activate human umbilical vein endothelial cells (HUVECs). Within 20 h of incubation, the more sulfated coatings induced the HUVECS to the form tube-like structures accompanied by an increased expression of angiogenic-associated genes, such as angiopoietin-1 and VEGF A. This may be a cost-effective approach to modify 2D/3D constructs to instruct angiogenic cells towards the formation of neo-vascularization, driven by multiple and synergistic stimulations from the PL combined with sulfated polysaccharides. The presence, or fast induction, of a stable and mature vasculature inside 3D constructs is crucial for new tissue formation and its viability. This has been one of the major tissue engineering challenges, limiting the dimensions of efficient tissue constructs. Many approaches based on cells, growth factors, 3D bioprinting and channel incorporation have been proposed. Herein, we explored a versatile technique, layer-by-layer assembling in combination with platelet lysate (PL), that is a cost-effective source of many potent pro-angiogenic proteins and growth factors. Results suggest that the combination of PL with sulfated polyelectrolytes might be used to introduce interfaces onto 2D/3D constructs with potential to induce the formation of cell-based tubular structures. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

ETS transcription factor ETV2/ER71/Etsrp in hematopoietic and vascular development, injury, and regeneration.

PubMed

Zhao, Haiyong; Xu, Canxin; Lee, Tae-Jin; Liu, Fang; Choi, Kyunghee

2017-04-01

The major goal in regenerative medicine is to repair and restore injured, diseased or aged tissue function, thereby promoting general health. As such, the field of regenerative medicine has great translational potential in undertaking many of the health concerns and needs that we currently face. In particular, hematopoietic and vascular systems supply oxygen and nutrients and thus play critical roles in tissue development and tissue regeneration. Additionally, tissue vasculature serves as a tissue stem cell niche and thus contributes to tissue homeostasis. Notably, hematopoietic and vascular systems are sensitive to injury and subject to regeneration. As such, successful hematopoietic and vascular regeneration is prerequisite for efficient tissue repair and organismal survival and health. Recent studies have established that the interplay among the ETS transcription factor ETV2, vascular endothelial growth factor, and its receptor VEGFR2/FLK1 is essential for hematopoietic and vascular development. Emerging studies also support the role of these three factors and possible interplay in hematopoietic and vascular regeneration. Comprehensive understanding of the molecular mechanisms involved in the regulation and function of these three factors may lead to more effective approaches in promoting tissue repair and regeneration. Developmental Dynamics 246:318-327, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Evening primrose oil or forskolin ameliorates celecoxib-enhanced upregulation of tissue factor expression in mice subjected to lipopolysaccharide-induced endotoxemia.

PubMed

Mosaad, Sarah M; Zaitone, Sawsan A; Ahmed, Amal A M; Abo-Elmatty, Dina M; El-Baz, Amani A; Moustafa, Yasser M

2017-05-01

Celecoxib, a selective cyclooxygenase-2 inhibitor, produces thrombotic events in patients predisposed to cardiovascular risk factors. One theory reported an increase in endothelial expression of tissue factor (TF) as a predisposing factor. This work explored the effect of evening primrose oil (EPO), a source of prostaglandin E1, and forskolin (a cyclic adenosine monophosphate stimulator) against the prothrombotic effect of celecoxib in mice. Lipopolysaccharide mouse model of endotoxemia was used to induce an upregulation of TF activity. Male mice received celecoxib (25 mg/kg), celecoxib plus EPO, or celecoxib plus forskolin for 4 weeks and then subjected to a prothrombotic challenge in the form of an intraperitoneal injection of lipopolysaccharide. Results showed an increase in plasma TF activity, endothelial TF expression, and thrombin-antithrombin (TAT) but lower antithrombin III (ATIII) level in mice that received celecoxib in comparison to those that received the vehicle. Adding EPO or forskolin to celecoxib regimen significantly decreased the prothrombotic effect of celecoxib. A positive correlation (r = 0.8501) was found between TF activity and TAT. Co-administration of EPO or forskolin decreased the activity of TF and mitigated the prothrombotic effect of celecoxib. Therefore, these combinations may have the utility to abrogate the prothrombotic adverse effect of celecoxib in clinical setting.

Low-Energy Ultrasound Treatment Improves Regional Tumor Vessel Infarction by Retargeted Tissue Factor.

PubMed

Brand, Caroline; Dencks, Stefanie; Schmitz, Georg; Mühlmeister, Mareike; Stypmann, Jörg; Ross, Rebecca; Hintelmann, Heike; Schliemann, Christoph; Müller-Tidow, Carsten; Mesters, Rolf M; Berdel, Wolfgang E; Schwöppe, Christian

2015-07-01

To enhance the regional antitumor activity of the vascular-targeting agent truncated tissue factor (tTF)-NGR by combining the therapy with low-energy ultrasound (US) treatment. For the in vitro US exposure of human umbilical vein endothelial cells (HUVECs), cells were put in the focus of a US transducer. For analysis of the US-induced phosphatidylserine (PS) surface concentration on HUVECs, flow cytometry was used. To demonstrate the differences in the procoagulatory efficacy of TF-derivative tTF-NGR on binding to HUVECs with a low versus high surface concentration of PS, we performed factor X activation assays. For low-energy US pretreatment, HT1080 fibrosarcoma xenotransplant-bearing nude mice were treated by tumor-regional US-mediated stimulation (ie, destruction) of microbubbles. The therapy cohorts received the tumor vessel-infarcting tTF-NGR protein with or without US pretreatment (5 minutes after US stimulation via intraperitoneal injection on 3 consecutive days). Combination therapy experiments with xenotransplant-bearing nude mice significantly increased the antitumor activity of tTF-NGR by regional low-energy US destruction of vascular microbubbles in tumor vessels shortly before application of tTF-NGR (P < .05). Mechanistic studies proved the upregulation of anionic PS on the outer leaflet of the lipid bilayer of endothelial cell membranes by low-energy US and a consecutive higher potential of these preapoptotic endothelial cells to activate coagulation via tTF-NGR and coagulation factor X as being a basis for this synergistic activity. Combining retargeted tTF to tumor vessels with proapoptotic stimuli for the tumor vascular endothelium increases the antitumor effects of tumor vascular infarction. Ultrasound treatment may thus be useful in this respect for regional tumor therapy. © 2015 by the American Institute of Ultrasound in Medicine.

Anti-Cancer Activity of an Osthole Derivative, NBM-T-BMX-OS01: Targeting Vascular Endothelial Growth Factor Receptor Signaling and Angiogenesis

PubMed Central

Chiu, Pei-Ting; Ho, Shiau-Jing; Wang, Chi-Han; Chi, Chih-Chin; Huang, Yu-Han; Lee, Cheng-Feng; Li, Ying-Shiuan; Ou, George; Hsu, Ming-Jen

2013-01-01

Angiogenesis occurs during tissue growth, development and wound healing. It is also required for tumor progression and represents a rational target for therapeutic intervention. NBM-T-BMX-OS01 (BMX), derived from the semisynthesis of osthole, an active ingredient isolated from Chinese herb Cnidium monnieri (L.) Cuss., was recently shown to enhance learning and memory in rats. In this study, we characterized the anti-angiogenic activities of NBM-T-BMX-OS01 (BMX) in an effort to develop novel inhibitors to suppress angiogenesis and tumor growth. BMX inhibited vascular endothelial growth factor (VEGF)-induced proliferation, migration and endothelial tube formation in human umbilical endothelial cells (HUVECs). BMX also attenuated VEGF-induced microvessel sprouting from aortic rings ex vivo and reduced HCT116 colorectal cancer cells-induced angiogenesis in vivo. Moreover, BMX inhibited the phosphorylation of VEGFR2, FAK, Akt and ERK in HUVECs exposed to VEGF. BMX was also shown to inhibit HCT116 cell proliferation and to suppress the growth of subcutaneous xenografts of HCT116 cells in vivo. Taken together, this study provides evidence that BMX modulates vascular endothelial cell remodeling and leads to the inhibition of tumor angiogenesis. These results also support the role of BMX as a potential drug candidate and warrant the clinical development in the treatment of cancer. PMID:24312323

Thymosin β4 promotes endothelial progenitor cell angiogenesis via a vascular endothelial growth factor‑dependent mechanism.

PubMed

Zhao, Yanbo; Song, Jiale; Bi, Xukun; Gao, Jing; Shen, Zhida; Zhu, Junhui; Fu, Guosheng

2018-06-20

Endothelial progenitor cells (EPCs) are a promising cell source for tissue repair and regeneration, predominantly through angiogenesis promotion. Paracrine functions serve a pivotal role in EPC‑mediated angiogenesis, which may be impaired by various cardiovascular risk factors. Therefore, it is important to identify a solution that optimizes the paracrine function of EPCs. Thymosin β4 (Tβ4) is a peptide with the potential to promote tissue regeneration and wound healing. A previous study demonstrated that Tβ4 enhances the EPC‑mediated angiogenesis of the ischemic myocardium. In the present study, whether Tβ4 improved angiogenesis by enhancing the paracrine effects of EPCs was investigated. A tube formation assay was used to assess the effect of angiogenesis, and the paracrine effects were measured using an ELISA kit. The results indicated that Tβ4 improved the paracrine effects of EPCs, evidenced by an increase in the expression of vascular endothelial growth factor (VEGF). EPC‑conditioned medium (EPC‑CM) significantly promoted human umbilical vein endothelial cell angiogenesis in vitro, which was further enhanced by pretreatment with Tβ4. The effect of Tβ4 pretreated EPC‑CM on angiogenesis was abolished by VEGF neutralizing antibody in vitro, indicating that increased VEGF secretion had a pivotal role in Tβ4‑mediated EPC angiogenesis. Furthermore, transplantation of EPCs pretreated with Tβ4 into infarcted rat hearts resulted in significantly higher VEGF expression in the border zone, compared with EPC transplantation alone. To further investigate whether the Akt/eNOS pathway was involved in Tβ4‑induced VEGF secretion in EPCs, the expression levels of VEGF in EPC‑CM were significantly decreased following knockdown of Akt or eNOS by small interfering RNA transfection. In conclusion, Tβ4 significantly increased angiogenesis by enhancing the paracrine effects of EPCs, evidenced by the increased expression of VEGF. The RAC‑α serine/threonine‑protein kinase/endothelial nitric oxide synthase signal transduction pathway was involved in the regulation of Tβ4‑induced VEGF secretion in EPCs. Further studies are required to investigate the long‑term prognosis of patients with coronary heart disease following Tβ4‑pretreated EPC transplantation.

Human endothelial cell growth and phenotypic expression on three dimensional poly(lactide-co-glycolide) sintered microsphere scaffolds for bone tissue engineering.

PubMed

Jabbarzadeh, Ehsan; Jiang, Tao; Deng, Meng; Nair, Lakshmi S; Khan, Yusuf M; Laurencin, Cato T

2007-12-01

Bone tissue engineering offers promising alternatives to repair and restore tissues. Our laboratory has employed poly(lactide-co-glycolide) PLAGA microspheres to develop a three dimensional (3-D) porous bioresorbable scaffold with a biomimetic pore structure. Osseous healing and integration with the surrounding tissue depends in part on new blood vessel formation within the porous structure. Since endothelial cells play a key role in angiogenesis (formation of new blood vessels from pre-existing vasculature), the purpose of this study was to better understand human endothelial cell attachment, viability, growth, and phenotypic expression on sintered PLAGA microsphere scaffold. Scanning electron microscopy (SEM) examination showed cells attaching to the surface of microspheres and bridging the pores between the microspheres. Cell proliferation studies indicated that cell number increased during early stages and reached a plateau between days 10 and 14. Immunofluorescent staining for actin showed that cells were proliferating three dimensionally through the scaffolds while staining for PECAM-1 (platelet endothelial cell adhesion molecule) displayed typical localization at cell-cell contacts. Gene expression analysis showed that endothelial cells grown on PLAGA scaffolds maintained their normal characteristic phenotype. The cell proliferation and phenotypic expression were independent of scaffold pore architecture. These results demonstrate that PLAGA sintered microsphere scaffolds can support the growth and biological functions of human endothelial cells. The insights from this study should aid future studies aimed at enhancing angiogenesis in three dimensional tissue engineered scaffolds.

Angiogenic Potential and Secretome of Human Apical Papilla Mesenchymal Stem Cells in Various Stress Microenvironments.

PubMed

Bakopoulou, Athina; Kritis, Aristeidis; Andreadis, Dimitrios; Papachristou, Eleni; Leyhausen, Gabriele; Koidis, Petros; Geurtsen, Werner; Tsiftsoglou, Asterios

2015-11-01

Stem cells from the apical papilla (SCAP) of human adult teeth are considered an accessible source of cells with angiogenic properties. The aims of this study were to investigate the endothelial transdifferentiation of SCAP, the secretion of pro- and antiangiogenic factors from SCAP, and the paracrine effects of SCAP when exposed to environmental stress to stimulate tissue damage. SCAP were exposed to serum deprivation (SD), glucose deprivation (GD), and oxygen deprivation/hypoxia (OD) conditions, individually or in combination. Endothelial transdifferentiation was evaluated by in vitro capillary-like formation assays, real-time polymerase chain reaction, western blot, and flow cytometric analyses of angiogenesis-related markers; secretome by antibody arrays and enzyme-linked immunosorbent assays (ELISA); and paracrine impact on human umbilical vein endothelial cells (HUVECs) by in vitro transwell migration and capillary-like formation assays. The short-term exposure of SCAP to glucose/oxygen deprivation (GOD) in the presence, but mainly in deprivation, of serum (SGOD) elicited a proangiogenesis effect indicated by expression of angiogenesis-related genes involved in vascular endothelial growth factor (VEGF)/VEGFR and angiopoietins/Tie pathways. This effect was unachievable under SD in normoxia, suggesting that the critical microenvironmental condition inducing rapid endothelial shift of SCAP is the combination of SGOD. Interestingly, SCAP showed high adaptability to these adverse conditions, retaining cell viability and acquiring a capillary-forming phenotype. SCAP secreted higher numbers and amounts of pro- (angiogenin, IGFBP-3, VEGF) and lower amounts of antiangiogenic factors (serpin-E1, TIMP-1, TSP-1) under SGOD compared with SOD or SD alone. Finally, secretome obtained under SGOD was most effective in inducing migration and capillary-like formation by HUVECs. These data provide new evidence on the microenvironmental factors favoring endothelial transdifferentiation of SCAP, uncovering the molecular mechanisms regulating their fate. They also validate the angiogenic properties of their secretome giving insights into preconditioning strategies enhancing their therapeutic potential.

Effect of the PI3K/AKT signaling pathway on hypoxia-induced proliferation and differentiation of bone marrow-derived mesenchymal stem cells

PubMed Central

Sheng, Lingling; Mao, Xiyuan; Yu, Qingxiong; Yu, Dong

2017-01-01

Bone marrow-derived mesenchymal stem cell (BM-MSC) transplantation has been demonstrated to be an effective way of augmenting angiogenesis of ischemic tissue. The low oxygen conditions in ischemic tissue directly affect the biological behavior of engrafted cells. However, to date, the mechanism through which hypoxia regulates self-renewal, differentiation and paracrine function of BM-MSCs remains unclear. Clarification of this mechanism would be beneficial to the use of stem cell-based therapy. The PI3K/AKT pathway has been extensively investigated for its role in cell proliferation, cell transformation, paracrine function and angiogenesis. The present study aimed to analyze the role of PI3K/AKT pathway in hypoxia-induced proliferation of BM-MSCs and their differentiation into endothelial cells in vitro by the application of LY294002, a PI3K/AKT pathway inhibitor, with cells cultured in normoxia serving as a control. The results showed that rat BM-MSCs at passage 3 and 4 displayed only few phenotypical differences in the expression of surface antigens as detected by flow cytometry. When compared with the cells treated in normoxia, the proliferation of BM-MSCs in hypoxia was promoted, a greater number of cells expressed CD31 and a higher expression of vascular endothelial growth factor was observed after culture in hypoxic conditions. However, by inhibiting with LY294002, these changes induced by hypoxia were partly inhibited. In conclusion, the present study showed that the PI3K/AKT pathway served an important role in hypoxia-enhanced in vitro proliferation of BM-MSCs and their differentiation into endothelial cells and paracrine vascular endothelial growth factor. PMID:28123468

The Effect of Levonorgestrel on Fibrinolytic Factors in Human Endometrial Endothelial Cells.

PubMed

Pakrashi, Tarita; Taylor, Joelle E; Nelson, Ashley; Archer, David F; Jacot, Terry

2016-11-01

The levonorgestrel-releasing intrauterine system is considered a highly effective treatment of heavy menstrual bleeding (HMB). While LNG has established effects on the stromal and glandular compartments of the endometrial tissue, its effect on the endometrial endothelial cells has not been investigated. We examined whether LNG regulates fibrinolytic factors, tissue plasminogen activator (tPA), and urokinase plasminogen activator (uPA) secreted by human endometrial endothelial cells (HEECs) and determined the steroid receptor through which LNG exerts its effect on the endothelium. The HEECs were treated with LNG or progesterone and levels of tPA and plasminogen activator inhibitor 1 (PAI-1) measured. The HEECs were specifically examined for the presence of androgen receptors through Western blot. Levonorgestrel ± flutamide were added to HEECs and the levels of tPA and uPA were examined. An enzyme-linked immunosorbent assay performed on culture media confirmed a statistically significant decrease in tPA levels in cells treated with LNG (77.80% ± 8.0% of control; n = 5, P < .05 vs control) but not progesterone. The androgen receptor (110 kDa) was detected in HEEC lysates. The decrease in tPA was blocked by the addition of flutamide (101.3% ± 16% of control), a classic nonsteroidal androgen receptor blocker. There was no change in uPA or PAI-1 levels in cells treated with LNG. Levonorgestrel decreases tPA levels through the androgen receptor in HEECs. Thus, LNG inhibits tPA secretion by the endometrial endothelial cell. This response suggests reduction in HMB with LNG-IUS could reflect an LNG-mediated promotion of hemostasis. © The Author(s) 2016.

Expression of the stem cell factor in fibroblasts, endothelial cells, and macrophages in periapical tissues in human chronic periapical diseases.

PubMed

Shen, S Q; Wang, R; Huang, S G

2017-03-08

Stem cell factor (SCF), an important stem cell cytokine, has multiple functions. Fibroblasts (FBs), mature mast cells, endothelial cells (ECs), and eosinophil granulocytes can produce SCF in the inflammatory process. Therefore, we aimed to observe SCF expression in FBs, ECs, and macrophages (MPs) in periapical tissues in human chronic periapical disease and investigate the effects of cells expressing SCF in pathogenesis of the disease. Healthy (N = 20), periapical cyst (N = 15), and periapical granuloma (N = 15) tissues were fixed in 10% formalin for 48 h, embedded in paraffin, and stained with hematoxylin and eosin to observe histological changes. SCF expression was observed in FBs, ECs, and MPs in periapical tissues by double immunofluorescence. CD334, CD31, and CD14 are specific markers of FBs, ECs, and MPs, respectively. Results showed that densities of CD334-SCF double-positive FBs, CD31-SCF double-positive ECs, and CD14-SCF double-positive MPs were significantly increased in periapical tissue groups (P < 0.01). There were no significant differences in CD334-SCF double-positive FB and CD31-SCF double-positive EC levels between the two periapical tissue groups (P > 0.05). CD14-SCF double-positive MP density was considerably higher in periapical granulomas than in cysts (P < 0.01). FB, EC, and MP levels were significantly high and densities of CD334-SCF double-positive FBs, CD31-SCF double-positive ECs, and CD14-SCF double-positive MPs improved considerably in chronic periapical tissues, suggesting that the cells might be related to occurrence, development, and pathogenesis of chronic periapical disease.

Tissue quality of eye-bank-prepared precut corneas for Descemet's stripping automated endothelial keratoplasty.

PubMed

Nelson, Brian A; Ritenour, Rusty J

2014-02-01

To evaluate endothelial cell density (ECD) of eye-bank-prepared tissue for use in Descemet's stripping automated endothelial keratoplasty (DSAEK). Prospective case series of consecutive corneal tissue prepared for DSAEK surgery. Sixty-seven sequential corneal-scleral tissue specimens representing 48 human donors processed for use in DSAEK surgery by the Regional Tissue Bank (Halifax, Nova Scotia). Corneal-scleral donor tissue was obtained by in situ recovery. ECD was recorded using the EB-3000 XYZ (HAI Laboratories Inc, Lexington, MA) specular microscope within 24 hours of preservation. Before the tissue was dissected, the corneal thickness was measured using the DGH-550 PACHETTE 2 (DGH Technology, Exton, PA) ultrasound pachymeter. The dissection was performed using a 300-μm Moria ALTK model microkeratome (Moria Inc). The posterior bed thickness was measured, and the anterior flap was replaced. Endothelial cell count density was obtained after re-preservation. Complete measurements were obtained for 42 of 67 corneas. In 25 corneas it was not possible to obtain a postdissection ECD measurement. The mean ECD before dissection was 2806 ± 317 cells/mm(2). The mean ECD after dissection was 2772 ± 318 cells/mm(2). There was an average loss of 34 cells/mm(2) (95% CI -110 to 40 cells/mm(2), p = 0.3). This case series confirms that ECD is preserved when DSAEK tissue is prepared in advance of surgery by trained eye-bank technicians in a low-volume Canadian eye bank. It was difficult to obtain clear images of the endothelial cell layer postdissection, possibly because of tissue swelling or distortion. Sixty-six of 67 corneas included in the study were used for surgery. © 2013 Canadian Ophthalmological Society Published by Canadian Ophthalmological Society All rights reserved.

Heterologous expression of Streptococcus mutans Cnm in Lactococcus lactis promotes intracellular invasion, adhesion to human cardiac tissues and virulence.

PubMed

Freires, Irlan A; Avilés-Reyes, Alejandro; Kitten, Todd; Simpson-Haidaris, P J; Swartz, Michael; Knight, Peter A; Rosalen, Pedro L; Lemos, José A; Abranches, Jacqueline

2017-01-02

In S. mutans, the expression of the surface glycoprotein Cnm mediates binding to extracellular matrix proteins, endothelial cell invasion and virulence in the Galleria mellonella invertebrate model. To further characterize Cnm as a virulence factor, the cnm gene from S. mutans strain OMZ175 was expressed in the non-pathogenic Lactococcus lactis NZ9800 using a nisin-inducible system. Despite the absence of the machinery necessary for Cnm glycosylation, Western blot and immunofluorescence microscopy analyses demonstrated that Cnm was effectively expressed and translocated to the cell wall of L. lactis. Similar to S. mutans, expression of Cnm in L. lactis enabled robust binding to collagen and laminin, invasion of human coronary artery endothelial cells and increased virulence in G. mellonella. Using an ex vivo human heart tissue colonization model, we showed that Cnm-positive strains of either S. mutans or L. lactis outcompete their Cnm-negative counterparts for tissue colonization. Finally, Cnm expression facilitated L. lactis adhesion and colonization in a rabbit model of infective endocarditis. Collectively, our results provide unequivocal evidence that binding to extracellular matrices mediated by Cnm is an important virulence attribute of S. mutans and confirm the usefulness of the L. lactis heterologous system for further characterization of bacterial virulence factors.

Mesenchymal Stem/Multipotent Stromal Cells from Human Decidua Basalis Reduce Endothelial Cell Activation.

PubMed

Alshabibi, Manal A; Al Huqail, Al Joharah; Khatlani, Tanvir; Abomaray, Fawaz M; Alaskar, Ahmed S; Alawad, Abdullah O; Kalionis, Bill; Abumaree, Mohamed Hassan

2017-09-15

Recently, we reported the isolation and characterization of mesenchymal stem cells from the decidua basalis of human placenta (DBMSCs). These cells express a unique combination of molecules involved in many important cellular functions, which make them good candidates for cell-based therapies. The endothelium is a highly specialized, metabolically active interface between blood and the underlying tissues. Inflammatory factors stimulate the endothelium to undergo a change to a proinflammatory and procoagulant state (ie, endothelial cell activation). An initial response to endothelial cell activation is monocyte adhesion. Activation typically involves increased proliferation and enhanced expression of adhesion and inflammatory markers by endothelial cells. Sustained endothelial cell activation leads to a type of damage to the body associated with inflammatory diseases, such as atherosclerosis. In this study, we examined the ability of DBMSCs to protect endothelial cells from activation through monocyte adhesion, by modulating endothelial proliferation, migration, adhesion, and inflammatory marker expression. Endothelial cells were cocultured with DBMSCs, monocytes, monocyte-pretreated with DBMSCs and DBMSC-pretreated with monocytes were also evaluated. Monocyte adhesion to endothelial cells was examined following treatment with DBMSCs. Expression of endothelial cell adhesion and inflammatory markers was also analyzed. The interaction between DBMSCs and monocytes reduced endothelial cell proliferation and monocyte adhesion to endothelial cells. In contrast, endothelial cell migration increased in response to DBMSCs and monocytes. Endothelial cell expression of adhesion and inflammatory molecules was reduced by DBMSCs and DBMSC-pretreated with monocytes. The mechanism of reduced endothelial proliferation involved enhanced phosphorylation of the tumor suppressor protein p53. Our study shows for the first time that DBMSCs protect endothelial cells from activation by inflammation triggered by monocyte adhesion and increased endothelial cell proliferation. These events are manifest in inflammatory diseases, such as atherosclerosis. Therefore, our results suggest that DBMSCs could be usefully employed as a therapeutic strategy for atherosclerosis.

Regulation and function of endothelial glycocalyx layer in vascular diseases.

PubMed

Sieve, Irina; Münster-Kühnel, Anja K; Hilfiker-Kleiner, Denise

2018-01-01

In the vascular system, the endothelial surface layer (ESL) as the inner surface of blood vessels affects mechanotransduction, vascular permeability, rheology, thrombogenesis, and leukocyte adhesion. It creates barriers between endothelial cells and blood and neighbouring cells. The glycocalyx, composed of glycoconjugates and proteoglycans, is an integral component of the ESL and a key element in inter- and intracellular communication and tissue homeostasis. In pathophysiological conditions (atherosclerosis, infection, ischemia/reperfusion injury, diabetes, trauma and acute lung injury) glycocalyx-degrading factors, i.e. reactive oxygen and nitrogen species, matrix metalloproteinases, heparanase and sialidases, damage the ESL, thereby impairing endothelial functions. This leads to increased capillary permeability, leucocyte-endothelium interactions, thrombosis and vascular inflammation, the latter further driving glycocalyx destruction. The present review highlights current knowledge on the vasculoprotective role of the ESL, with specific emphasis on its remodelling in inflammatory vascular diseases and discusses its potential as a novel therapeutic target to treat vascular pathologies. Copyright © 2017 Elsevier Inc. All rights reserved.

VEGF-incorporated biomimetic poly(lactide-co-glycolide) sintered microsphere scaffolds for bone tissue engineering.

PubMed

Jabbarzadeh, Ehsan; Deng, Meng; Lv, Qing; Jiang, Tao; Khan, Yusuf M; Nair, Lakshmi S; Laurencin, Cato T

2012-11-01

Regenerative engineering approaches utilizing biomimetic synthetic scaffolds provide alternative strategies to repair and restore damaged bone. The efficacy of the scaffolds for functional bone regeneration critically depends on their ability to induce and support vascular infiltration. In the present study, three-dimensional (3D) biomimetic poly(lactide-co-glycolide) (PLAGA) sintered microsphere scaffolds were developed by sintering together PLAGA microspheres followed by nucleation of minerals in a simulated body fluid. Further, the angiogenic potential of vascular endothelial growth factor (VEGF)-incorporated mineralized PLAGA scaffolds were examined by monitoring the growth and phenotypic expression of endothelial cells on scaffolds. Scanning electron microscopy micrographs confirmed the growth of bone-like mineral layers on the surface of microspheres. The mineralized PLAGA scaffolds possessed interconnectivity and a compressive modulus of 402 ± 61 MPa and compressive strength of 14.6 ± 2.9 MPa. Mineralized scaffolds supported the attachment and growth and normal phenotypic expression of endothelial cells. Further, precipitation of apatite layer on PLAGA scaffolds resulted in an enhanced VEGF adsorption and prolonged release compared to nonmineralized PLAGA and, thus, a significant increase in endothelial cell proliferation. Together, these results demonstrated the potential of VEGF-incorporated biomimetic PLAGA sintered microsphere scaffolds for bone tissue engineering as they possess the combined effects of osteointegrativity and angiogenesis. Copyright © 2012 Wiley Periodicals, Inc.

Simultaneous isolation of vascular endothelial cells and mesenchymal stem cells from the human umbilical cord.

PubMed

Kadam, Sachin S; Tiwari, Shubha; Bhonde, Ramesh R

2009-01-01

The umbilical cord represents the link between mother and fetus during pregnancy. This cord is usually discarded as a biological waste after the child's birth; however, its importance as a "store house" of stem cells has been explored recently. We developed a method of simultaneous isolation of endothelial cells (ECs) from the vein and mesenchymal stem cells from umbilical cord Wharton's jelly of the same cord. The isolation protocol has been simplified, modified, and improvised with respect to choice of enzyme and enzyme mixture, digestion time, cell yield, cell growth, and culture medium. Isolated human umbilical vascular ECs (hUVECs) were positive for von-Willibrand factor, a classical endothelial marker, and could form capillary-like structures when seeded on Matrigel, thus proving their functionality. The isolated human umbilical cord mesenchymal stem cells (hUCMSCs) were found positive for CD44, CD90, CD 73, and CD117 and were found negative for CD33, CD34, CD45, and CD105 surface markers; they were also positive for cytoskeleton markers of smooth muscle actin and vimentin. The hUCMSCs showed multilineage differentiation potential and differentiated into adipogenic, chondrogenic, osteogenic, and neuronal lineages under influence of lineage specific differentiation medium. Thus, isolating endothelial cells as well as mesenchymal cells from the same umbilical cord could lead to complete utilization of the available tissue for the tissue engineering and cell therapy.

The regulatory mechanism of Hsp90{alpha} secretion from endothelial cells and its role in angiogenesis during wound healing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Xiaomin; Beijing Key Laboratory for Protein Therapeutics, Tsinghua University, Beijing 100084; Cancer Biology Laboratory, School of Life Sciences, Tsinghua University, Beijing 100084

2010-07-16

Research highlights: {yields} Growth factors such as bFGF, VEGF, PDGF and SDF-1 stimulate Hsp90{alpha} secretion from endothelial cells. {yields} Secreted Hsp90{alpha} localizes on the leading edge of activated endothelial cells. {yields} Secreted Hsp90{alpha} promotes angiogenesis in wound healing. -- Abstract: Heat shock protein 90{alpha} (Hsp90{alpha}) is a ubiquitously expressed molecular chaperone, which is essential for the maintenance of eukaryote homeostasis. Hsp90{alpha} can also be secreted extracellularly and is associated with several physiological and pathological processes including wound healing, cancer, infectious diseases and diabetes. Angiogenesis, defined as the sprouting of new blood vessels from pre-existing capillaries via endothelial cell proliferation andmore » migration, commonly occurs in and contributes to the above mentioned processes. However, the secretion of Hsp90{alpha} from endothelial cells and also its function in angiogenesis are still unclear. Here we investigated the role of extracellular Hsp90{alpha} in angiogenesis using dermal endothelial cells in vitro and a wound healing model in vivo. We find that the secretion of Hsp90{alpha} but not Hsp90{beta} is increased in activated endothelial cells with the induction of angiogenic factors and matrix proteins. Secreted Hsp90{alpha} localizes on the leading edge of endothelial cells and promotes their angiogenic activities, whereas Hsp90{alpha} neutralizing antibodies reverse the effect. Furthermore, using a mouse skin wound healing model in vivo, we demonstrate that extracellular Hsp90{alpha} localizes on blood vessels in granulation tissues of wounded skin and promotes angiogenesis during wound healing. Taken together, our study reveals that Hsp90{alpha} can be secreted by activated endothelial cells and is a positive regulator of angiogenesis, suggesting the potential application of Hsp90{alpha} as a stimulator for wound repair.« less

Stromal cells in chronic inflammation and tertiary lymphoid organ formation.

PubMed

Buckley, Christopher D; Barone, Francesca; Nayar, Saba; Bénézech, Cecile; Caamaño, Jorge

2015-01-01

Inflammation is an unstable state. It either resolves or persists. Why inflammation persists and the factors that define tissue tropism remain obscure. Increasing evidence suggests that tissue-resident stromal cells not only provide positional memory but also actively regulate the differential accumulation of inflammatory cells within inflamed tissues. Furthermore, at many sites of chronic inflammation, structures that mimic secondary lymphoid tissues are observed, suggesting that chronic inflammation and lymphoid tissue formation share common activation programs. Similarly, blood and lymphatic endothelial cells contribute to tissue homeostasis and disease persistence in chronic inflammation. This review highlights our increasing understanding of the role of stromal cells in inflammation and summarizes the novel immunological role that stromal cells exert in the persistence of inflammatory diseases.

Covalently immobilized platelet-derived growth factor-BB promotes angiogenesis in biomimetic poly(ethylene glycol) hydrogels

PubMed Central

Saik, Jennifer E.; Gould, Daniel J.; Watkins, Emily M.; Dickinson, Mary E.; West, Jennifer L.

2011-01-01

The field of tissue engineering is severely limited by a lack of microvascularization in tissue engineered constructs. Biomimetic poly(ethylene glycol) hydrogels containing covalently immobilized platelet-derived growth factor BB (PDGF-BB) were developed to promote angiogenesis. Poly(ethylene glycol) hydrogels resist protein absorption and subsequent non-specific cell adhesion, thus providing a “blank slate”, which can be modified through the incorporation of cell adhesive ligands and growth factors. PDGF-BB is a key angiogenic protein able to support neovessel stabilization by inducing functional anastomoses and recruiting pericytes. Due to the widespread effects of PDGF in the body and a half-life of only 30 min in circulating blood, immobilization of PDGF-BB may be necessary. In this work bioactive, covalently immobilized PDGF-BB was shown to induce tubulogenesis on two-dimensional modified surfaces, migration in three-dimensional (3D) degradable hydrogels and angiogenesis in a mouse cornea micro-pocket angiogenesis assay. Covalently immobilized PDGF-BB was also used in combination with covalently immobilized fibroblast growth factor-2, which led to significantly increased endothelial cell migration in 3D degradable hydrogels compared with the presentation of each factor alone. When a co-culture of endothelial cells and mouse pericyte precursor 10T1/2 cells was seeded onto modified surfaces tubule formation was independent of surface modifications with covalently immobilized growth factors. Furthermore, the combination of soluble PDGF-BB and immobilized PDGF-BB induced a more robust vascular response compared with soluble PDGF-BB alone when implanted into an in vivo mouse cornea micropocket angiogenesis assay. Based on these results, we believe bioactive hydrogels can be tailored to improve the formation of functional microvasculature for tissue engineering. PMID:20801242

Platelet lysate gel and endothelial progenitors stimulate microvascular network formation in vitro: tissue engineering implications.

PubMed

Fortunato, Tiago M; Beltrami, Cristina; Emanueli, Costanza; De Bank, Paul A; Pula, Giordano

2016-05-04

Revascularisation is a key step for tissue regeneration and complete organ engineering. We describe the generation of human platelet lysate gel (hPLG), an extracellular matrix preparation from human platelets able to support the proliferation of endothelial colony forming cells (ECFCs) in 2D cultures and the formation of a complete microvascular network in vitro in 3D cultures. Existing extracellular matrix preparations require addition of high concentrations of recombinant growth factors and allow only limited formation of capillary-like structures. Additional advantages of our approach over existing extracellular matrices are the absence of any animal product in the composition hPLG and the possibility of obtaining hPLG from patients to generate homologous scaffolds for re-implantation. This discovery has the potential to accelerate the development of regenerative medicine applications based on implantation of microvascular networks expanded ex vivo or the generation of fully vascularised organs.

Platelet lysate gel and endothelial progenitors stimulate microvascular network formation in vitro: tissue engineering implications

PubMed Central

Fortunato, Tiago M.; Beltrami, Cristina; Emanueli, Costanza; De Bank, Paul A.; Pula, Giordano

2016-01-01

Revascularisation is a key step for tissue regeneration and complete organ engineering. We describe the generation of human platelet lysate gel (hPLG), an extracellular matrix preparation from human platelets able to support the proliferation of endothelial colony forming cells (ECFCs) in 2D cultures and the formation of a complete microvascular network in vitro in 3D cultures. Existing extracellular matrix preparations require addition of high concentrations of recombinant growth factors and allow only limited formation of capillary-like structures. Additional advantages of our approach over existing extracellular matrices are the absence of any animal product in the composition hPLG and the possibility of obtaining hPLG from patients to generate homologous scaffolds for re-implantation. This discovery has the potential to accelerate the development of regenerative medicine applications based on implantation of microvascular networks expanded ex vivo or the generation of fully vascularised organs. PMID:27141997

Patterning of Endothelial Cells and Mesenchymal Stem Cells by Laser-Assisted Bioprinting to Study Cell Migration.

PubMed

Bourget, Jean-Michel; Kérourédan, Olivia; Medina, Manuela; Rémy, Murielle; Thébaud, Noélie Brunehilde; Bareille, Reine; Chassande, Olivier; Amédée, Joëlle; Catros, Sylvain; Devillard, Raphaël

2016-01-01

Tissue engineering of large organs is currently limited by the lack of potent vascularization in vitro . Tissue-engineered bone grafts can be prevascularized in vitro using endothelial cells (ECs). The microvascular network architecture could be controlled by printing ECs following a specific pattern. Using laser-assisted bioprinting, we investigated the effect of distance between printed cell islets and the influence of coprinted mesenchymal cells on migration. When printed alone, ECs spread out evenly on the collagen hydrogel, regardless of the distance between cell islets. However, when printed in coculture with mesenchymal cells by laser-assisted bioprinting, they remained in the printed area. Therefore, the presence of mesenchymal cell is mandatory in order to create a pattern that will be conserved over time. This work describes an interesting approach to study cell migration that could be reproduced to study the effect of trophic factors.

Patterning of Endothelial Cells and Mesenchymal Stem Cells by Laser-Assisted Bioprinting to Study Cell Migration

PubMed Central

Medina, Manuela; Rémy, Murielle; Thébaud, Noélie Brunehilde; Bareille, Reine; Chassande, Olivier; Amédée, Joëlle; Catros, Sylvain

2016-01-01

Tissue engineering of large organs is currently limited by the lack of potent vascularization in vitro. Tissue-engineered bone grafts can be prevascularized in vitro using endothelial cells (ECs). The microvascular network architecture could be controlled by printing ECs following a specific pattern. Using laser-assisted bioprinting, we investigated the effect of distance between printed cell islets and the influence of coprinted mesenchymal cells on migration. When printed alone, ECs spread out evenly on the collagen hydrogel, regardless of the distance between cell islets. However, when printed in coculture with mesenchymal cells by laser-assisted bioprinting, they remained in the printed area. Therefore, the presence of mesenchymal cell is mandatory in order to create a pattern that will be conserved over time. This work describes an interesting approach to study cell migration that could be reproduced to study the effect of trophic factors. PMID:27833916

Tissue-specific mechanical and geometrical control of cell viability and actin cytoskeleton alignment

NASA Astrophysics Data System (ADS)

Wang, Dong; Zheng, Wenfu; Xie, Yunyan; Gong, Peiyuan; Zhao, Fang; Yuan, Bo; Ma, Wanshun; Cui, Yan; Liu, Wenwen; Sun, Yi; Piel, Matthieu; Zhang, Wei; Jiang, Xingyu

2014-08-01

Different tissues have specific mechanical properties and cells of different geometries, such as elongated muscle cells and polygonal endothelial cells, which are precisely regulated during embryo development. However, the mechanisms that underlie these processes are not clear. Here, we built an in vitro model to mimic the cellular microenvironment of muscle by combining both mechanical stretch and geometrical control. We found that mechanical stretch was a key factor that determined the optimal geometry of myoblast C2C12 cells under stretch, whereas vascular endothelial cells and fibroblasts had no such dependency. We presented the first experimental evidence that can explain why myoblasts are destined to take the elongated geometry so as to survive and maintain parallel actin filaments along the stretching direction. The study is not only meaningful for the research on myogenesis but also has potential application in regenerative medicine.

Endothelial cell stimulating angiogenesis factor.

PubMed

Weiss, J B; McLaughlin, B

1998-04-01

Endothelial cell stimulating angiogenesis factor (ESAF) is a small (> 1000 Da) dialysable non-peptide molecule with potent angiogenic activity. ESAF activates the major pro-matrix metalloproteinases and also uniquely reactivates the complex of these active enzymes with their tissue inhibitors resulting in both active enzyme and inhibitor. These actions may be pivotal in its role as an angiogenic factor. ESAF is primarily involved in angiogenic conditions where inflammatory cells are not evident such as foetal bone growth and electrically stimulated skeletal muscles and proliferative retinopathy. However, high levels also occur in actively growing human intracranial tumours but it is not noticeably elevated in rheumatoid arthritic synovial fluid. Its extreme potency and low molecular mass make its structural determination difficult. Possible therapeutic applications would be in the treatment of ischaemic ulcers, acceleration of fracture repair, infertility and more modestly in the correction of baldness. Analogues of ESAF could be of value in treating angiogenic diseases such as psoriasis and proliferative retinopathy.

Exercise Training Prevents Coronary Endothelial Dysfunction in Type 2 Diabetic Mice.

PubMed

Lee, Sewon; Park, Yoonjung; Zhang, Cuihua

2011-10-01

Type 2 diabetes (T2D) is a leading risk factor for cardiovascular diseases including atherosclerosis and coronary heart disease. Exercise training (ET) is thought to have a beneficial effect on these disorders, but the basis for this effect is not fully understood. Because endothelial dysfunction plays a key role in the pathological events leading to cardiovascular complications in T2D, we hypothesized that the effects of ET will be evidenced by improvements in coronary endothelial function. To test this hypothesis, we assessed the effects of ET on vascular function of diabetic (db/db, Lepr(db)) mice by evaluating endothelial function of isolated coronary arterioles of wild-type (WT) and db/db mice with/without ET. Although dilation of vessels to the endothelial-independent vasodilator, sodium nitroprusside was not different between db/db and WT, dilation to the endothelial-dependent agonist, acetylcholine (ACh), was impaired in db/db compared to WT mice. Vasodilation to ACh was restored in db/db with ET and insulin sensitivity was improved in the db/db after ET. Exercise did not change body weight of db/db, but superoxide dismutase (SOD1 and SOD2) and phosphorylated- eNOS protein (Ser1177) expression in heart tissue was up-regulated whereas tumor necrosis factor-alpha (TNF-α) protein level was decreased by ET. Serum level of interleukin-6 (IL-6) was higher in db/db mice but ET decreased IL-6. This suggests that ET may improve endothelial function by increasing nitric oxide bioavailability as well as decreasing chronic inflammation. We suggest this connection may be the basis for the benefit of ET in T2D.

Effects of trauma, hemorrhagic shock, and chronic stress on lung vascular endothelial growth factor.

PubMed

Loftus, Tyler J; Thomson, Andrew J; Kannan, Kolenkode B; Alamo, Ines G; Ramos, Harry N; Whitley, Elizabeth E; Efron, Philip A; Mohr, Alicia M

2017-04-01

Vascular endothelial growth factor (VEGF) and its receptors (VEGFR-1 and VEGFR-2) regulate vascular permeability and endothelial cell survival. We hypothesized that hemorrhagic shock (HS) and chronic stress (CS) would increase expression of lung VEGF and its receptors, potentiating pulmonary edema in lung tissue. Male Sprague-Dawley rats aged 8-9 wk were randomized: naïve control, lung contusion (LC), LC followed by HS (LCHS), and LCHS with CS in a restraint cylinder for 2 h/d (LCHS/CS). Animals were sacrificed on days 1 and 7. Expressions of lung VEGF, VEGFR-1, and VEGFR-2 were determined by polymerase chain reaction. Lung Injury Score (LIS) was graded on light microscopy by inflammatory cell counts, interstitial edema, pulmonary edema, and alveolar integrity (range: 0 = normal; 8 = severe injury). Seven days after LC, lung VEGF and VEGFR-1 were increased, and lung tissue healed (LIS: 0.8 ± 0.8). However, 7 d after LCHS and LCHS/CS, lung VEGF and VEGFR-1 expressions were decreased. VEGFR-2 was also decreased after LCHS/CS. LIS was elevated 7 d after LCHS and LCHS/CS (6.5 ± 1.0 and 8.2 ± 0.8). Increased LIS after LCHS and LCHS/CS was because of higher inflammatory cell counts, increased interstitial edema, and loss of alveolar integrity, whereas pulmonary edema was unchanged. Elevation of lung VEGF and VEGFR-1 expressions after LC alone was associated with healing of injured lung tissue. Expressions of VEGF, VEGFR-1, and VEGFR-2 were reduced after LCHS and LCHS/CS, and injured lung tissue did not heal. Persistent lung injury after severe trauma was because of inflammation rather than pulmonary edema. Copyright © 2016 Elsevier Inc. All rights reserved.

A Review of String Vessels or Collapsed, Empty Basement Membrane Tubes

PubMed Central

Brown, William R.

2011-01-01

String vessels are thin connective tissue strands, remnants of capillaries, with no endothelial cells; they do not carry blood flow. They occur in numerous species, particularly in the central nervous system, but can occur in any tissue where capillaries have died. String vessels are often associated with pathologies such as Alzheimer’s disease, ischemia, and irradiation, but are also found in normal human brains from preterm babies to the aged. They provide a record of the original blood vessel location, but gradually disappear after months or years. There have been numerous studies of string vessels (acellular capillaries) in the retina, because retinal vessels can be seen in great detail in whole mounts after trypsin digestion. Capillary regression occurs by apoptosis, synchronously along capillary segments, with macrophages engulfing apoptotic endothelial cells. Macrophages may cause the apoptosis, or the regression may be triggered by loss of the endothelial cell survival factor VEGF. VEGF expression is induced by hypoxia and promotes capillary growth. Cessation of blood flow eliminates the shear stress that helps maintain endothelial cell survival. Capillaries can re-grow by proliferation and migration of endothelial cells into empty basement membrane tubes, which provide a structural scaffold, replete with signaling molecules. This is a problem in tumor control, but useful for recovery from capillary loss. There is an age-related waning of VEGF expression in response to hypoxia. This causes an age-related decline in cerebral angiogenesis and results in neuronal loss. It may also contribute to the proposed age-related loss of brain reserve. PMID:20634580

"All-laser" endothelial corneal transplant in human patients

NASA Astrophysics Data System (ADS)

Rossi, Francesca; Menabuoni, Luca; Malandrini, Alex; Canovetti, Annalisa; Lenzetti, Ivo; Pini, Roberto

2012-03-01

Femtosecond laser sculpturing of corneal tissue is commonly used for the preparation of endothelial flaps. Diode laser welding of ocular tissues is a procedure that enables minimally invasive suturing of tissues. The combination of these laser based techniques results in a new approach to minimally invasive ophthalmic surgery, such as in endothelial corneal transplant (or endothelial keratoplasty - EK). In this work we present the "all laser" EK performed in human subjects. 24 pseudophakic patients with bullous keratopathy underwent EK: the femtosecond laser was used to prepare the 100 ìm thick and 8.5 mm diameter donor Descemet endothelial flap. After staining the stromal layer of the donor flap with a liquid ICG solution, the donor flap was inserted in the recipient eye by the use of the Busin injector. Then, the endothelial layer was laser-welded to the recipient eye (10 laser spots around the periphery of the flap), in order to reduce the risk of postoperative dislocation of the transplanted flap. A transplanted flap engraftment was observed in all the treated eyes. The staining procedure used to perform laser welding also enabled to evidence the stromal side of the donor flap, so as the flap was always placed in the right side position. The endothelial cells counts in both the laserwelded flaps and in a control group were in good agreement. The proposed technique is easy to perform and enables the reduction of postoperative endothelial flap dislocations.

Scaffold-Free Tubular Tissues Created by a Bio-3D Printer Undergo Remodeling and Endothelialization when Implanted in Rat Aortae

PubMed Central

Itoh, Manabu; Nakayama, Koichi; Noguchi, Ryo; Kamohara, Keiji; Furukawa, Kojirou; Uchihashi, Kazuyoshi; Toda, Shuji; Oyama, Jun-ichi; Node, Koichi; Morita, Shigeki

2015-01-01

Background Small caliber vascular prostheses are not clinically available because synthetic vascular prostheses lack endothelial cells which modulate platelet activation, leukocyte adhesion, thrombosis, and the regulation of vasomotor tone by the production of vasoactive substances. We developed a novel method to create scaffold-free tubular tissue from multicellular spheroids (MCS) using a “Bio-3D printer”-based system. This system enables the creation of pre-designed three-dimensional structures using a computer controlled robotics system. With this system, we created a tubular structure and studied its biological features. Methods and Results Using a “Bio-3D printer,” we made scaffold-free tubular tissues (inner diameter of 1.5 mm) from a total of 500 MCSs (2.5× 104 cells per one MCS) composed of human umbilical vein endothelial cells (40%), human aortic smooth muscle cells (10%), and normal human dermal fibroblasts (50%). The tubular tissues were cultured in a perfusion system and implanted into the abdominal aortas of F344 nude rats. We assessed the flow by ultrasonography and performed histological examinations on the second (n = 5) and fifth (n = 5) day after implantation. All grafts were patent and remodeling of the tubular tissues (enlargement of the lumen area and thinning of the wall) was observed. A layer of endothelial cells was confirmed five days after implantation. Conclusions The scaffold-free tubular tissues made of MCS using a Bio-3D printer underwent remodeling and endothelialization. Further studies are warranted to elucidate the underlying mechanism of endothelialization and its function, as well as the long-term results. PMID:26325298

Targeting tissue factor-expressing tumor angiogenesis and tumors with EF24 conjugated to factor VIIa.

PubMed

Shoji, Mamoru; Sun, Aiming; Kisiel, Walter; Lu, Yang J; Shim, Hyunsuk; McCarey, Bernard E; Nichols, Christopher; Parker, Ernest T; Pohl, Jan; Mosley, Cara A; Alizadeh, Aaron R; Liotta, Dennis C; Snyder, James P

2008-04-01

Tissue factor (TF) is aberrantly expressed on tumor vascular endothelial cells (VECs) and on cancer cells in many malignant tumors, but not on normal VECs, making it a promising target for cancer therapy. As a transmembrane receptor for coagulation factor VIIa (fVIIa), TF forms a high-affinity complex with its cognate ligand, which is subsequently internalized through receptor-mediated endocytosis. Accordingly, we developed a method for selectively delivering EF24, a potent synthetic curcumin analog, to TF-expressing tumor vasculature and tumors using fVIIa as a drug carrier. EF24 was chemically conjugated to fVIIa through a tripeptide-chloromethyl ketone. After binding to TF-expressing targets by fVIIa, EF24 will be endocytosed along with the drug carrier and will exert its cytotoxicity. Our results showed that the conjugate inhibits vascular endothelial growth factor-induced angiogenesis in a rabbit cornea model and in a Matrigel model in athymic nude mice. The conjugate-induced apoptosis in tumor cells and significantly reduced tumor size in human breast cancer xenografts in athymic nude mice as compared with the unconjugated EF24. By conjugating potent drugs to fVIIa, this targeted drug delivery system has the potential to enhance therapeutic efficacy, while reducing toxic side effects. It may also prove to be useful for treating drug-resistant tumors and micro-metastases in addition to primary tumors.

Increased endothelial apoptotic cell density in human diabetic erectile tissue--comparison with clinical data.

PubMed

Costa, Carla; Soares, Raquel; Castela, Angela; Adães, Sara; Hastert, Véronique; Vendeira, Pedro; Virag, Ronald

2009-03-01

Erectile dysfunction (ED) is a common complication of diabetes. Endothelial cell (EC) dysfunction is one of the main mechanisms of diabetic ED. However, loss of EC integrity has never been assessed in human diabetic corpus cavernosum. To identify and quantify apoptotic cells in human diabetic and normal erectile tissue and to compare these results with each patient's clinical data and erection status. Eighteen cavernosal samples were collected, 13 from diabetics with ED and 5 from nondiabetic individuals. Cavernosal structure and cell proliferation status were evaluated by immunohistochemistry. Tissue integrity was assessed by terminal transferase dUTP nick end labeling assay, an index of apoptotic cell density (ACD) established and compared with each patient age, type of diabetes, arterial risk factors number, arterial/veno-occlusive disease, response to intracavernous vasoactive injections (ICI), and penile nitric oxide release test (PNORT). Establish an index of ACD and correlate those results with patient clinical data. Nondiabetic samples presented few scattered cells in apoptosis and an ACD of 7.15 +/- 0.44 (mean apoptotic cells/tissue area mm(2) +/- standard error). The diabetic group showed an increased ACD of 23.82 +/- 1.53, and apoptotic cells were located specifically at vascular sites. Rehabilitation of these endothelial lesions seemed impaired, as no evidence of EC proliferation was observed. Furthermore, higher ACD in diabetic individuals correlated to poor response to PNORT and to ICI. We provided evidence for the first time that loss of cavernosal EC integrity is a crucial event involved in diabetic ED. Furthermore, we were able to establish a threshold between ACD values and cavernosal tissue functionality, as assessed by PNORT and vasoactive ICI.

Mechanisms in the loss of capillaries in systemic sclerosis: angiogenesis versus vasculogenesis

PubMed Central

Manetti, Mirko; Guiducci, Serena; Ibba-Manneschi, Lidia; Matucci-Cerinic, Marco

2010-01-01

Abstract Systemic sclerosis (SSc, scleroderma) is a chronic, multisystem connective tissue disorder affecting the skin and various internal organs. Although the disease is characterized by a triad of widespread microangiopathy, fibrosis and autoimmunity, increasing evidence indicates that vascular damage is a primary event in the pathogenesis of SSc. The progressive vascular injury includes persistent endothelial cell activation/damage and apoptosis, intimal thickening, delamination, vessel narrowing and obliteration. These profound vascular changes lead to vascular tone dysfunction and reduced capillary blood flow, with consequent tissue ischemia and severe clinical manifestations, such as digital ulceration or amputation, pulmonary arterial hypertension and scleroderma renal crisis. The resulting tissue hypoxia induces complex cellular and molecular mechanisms in the attempt to recover endothelial cell function and tissue perfusion. Nevertheless, in SSc patients there is no evidence of significant angiogenesis and the disease evolves towards chronic tissue ischemia, with progressive and irreversible structural changes in multiple vascular beds culminating in the loss of capillaries. A severe imbalance between pro-angiogenic and angiostatic factors may also lead to impaired angiogenic response during SSc. Besides insufficient angiogenesis, defective vasculogenesis with altered numbers and functional defects of bone marrow-derived endothelial progenitor cells may contribute to the vascular pathogenesis of SSc. The purpose of this article is to review the contribution of recent studies to the understanding of the complex mechanisms of impaired vascular repair in SSc. Indeed, understanding the pathophysiology of SSc-associated vascular disease may be the key in dissecting the disease pathogenesis and developing novel therapies. Either angiogenic or vasculogenic mechanisms may potentially become in the future the target of therapeutic strategies to promote capillary regeneration in SSc. PMID:20132409

Development and characterization of hybrid tubular structure of PLCL porous scaffold with hMSCs/ECs cell sheet.

PubMed

Pangesty, Azizah Intan; Arahira, Takaaki; Todo, Mitsugu

2017-09-15

Tissue engineering offers an alternate approach to providing vascular graft with potential to grow similar with native tissue by seeding autologous cells into biodegradable scaffold. In this study, we developed a combining technique by layering a sheet of cells onto a porous tubular scaffold. The cell sheet prepared from co-culturing human mesenchymal stem cells (hMSCs) and endothelial cells (ECs) were able to infiltrate through porous structure of the tubular poly (lactide-co-caprolactone) (PLCL) scaffold and further proliferated on luminal wall within a week of culture. Moreover, the co-culture cell sheet within the tubular scaffold has demonstrated a faster proliferation rate than the monoculture cell sheet composed of MSCs only. We also found that the co-culture cell sheet expressed a strong angiogenic marker, including vascular endothelial growth factor (VEGF) and its receptor (VEGFR), as compared with the monoculture cell sheet within 2 weeks of culture, indicating that the co-culture system could induce differentiation into endothelial cell lineage. This combined technique would provide cellularization and maturation of vascular construct in relatively short period with a strong expression of angiogenic properties.

HIF-1α and VEGF expression correlates with thrombus remodeling in cases of intravascular papillary endothelial hyperplasia

PubMed Central

Kim, Sunzoo; Jun, Jae Hun; Kim, Jeongshik; Kim, Do Won; Jang, Yong Hyun; Lee, Weon Ju; Chung, Ho Yun; Lee, Seok-Jong

2013-01-01

Intravascular papillary endothelial hyperplasia (IPEH) is histopathologically characterized by endothelium-lined papillary structures encircling an acellular fibrin core. The process of IPEH pathogenesis is unclear. The purpose of our study was to identify histopathological and immunohistochemical characteristics of IPEH to better understand the pathogenesis of this disease. After reviewing microscopic and medical records from Kyungpook National University Hospital, we selected 16 cases of IPEH. Masson’s trichrome and immunohistochemical staining as well as hematoxylin-eosin staining for 16 cases of IPH were performed. Immunohistochemical studies included CD31, CD68, mast cell tryptase, hypoxia-inducible factor-1 (HIF-1α), and vascular endothelial growth factor (VEGF). Sections from all our cases showed three distinct histological regions including a papillary portion with hyalinized fibrous or fibroblastic cores, an area containing an unorganized thrombus, and organization area with an ingrowth of endothelial cells, myofibroblasts, and fibroblasts. In the organization area, HIF-1α-positive cells were identified in the loose connective tissue. Endothelial cells forming vascular channels were negative for HIF-1α while VEGF was highly expressed in both interstitial mononuclear and endothelial cells. In the papillary portion, the cellular cores were strongly positive for both HIF-1α and VEGF, but the acellular cores were negative. Our investigation confirmed that IPEH is a reactive lesion that incidentally arises during the organization process of older thrombi. It was also found that HIF-1α and VEGF expression was dependent on the thrombus remodeling stage in cases of IPEH. PMID:24294378

Human endothelial colony-forming cells expanded with an improved protocol are a useful endothelial cell source for scaffold-based tissue engineering.

PubMed

Denecke, Bernd; Horsch, Liska D; Radtke, Stefan; Fischer, Johannes C; Horn, Peter A; Giebel, Bernd

2015-11-01

One of the major challenges in tissue engineering is to supply larger three-dimensional (3D) bioengineered tissue transplants with sufficient amounts of nutrients and oxygen and to allow metabolite removal. Consequently, artificial vascularization strategies of such transplants are desired. One strategy focuses on endothelial cells capable of initiating new vessel formation, which are settled on scaffolds commonly used in tissue engineering. A bottleneck in this strategy is to obtain sufficient amounts of endothelial cells, as they can be harvested only in small quantities directly from human tissues. Thus, protocols are required to expand appropriate cells in sufficient amounts without interfering with their capability to settle on scaffold materials and to initiate vessel formation. Here, we analysed whether umbilical cord blood (CB)-derived endothelial colony-forming cells (ECFCs) fulfil these requirements. In a first set of experiments, we showed that marginally expanded ECFCs settle and survive on different scaffold biomaterials. Next, we improved ECFC culture conditions and developed a protocol for ECFC expansion compatible with 'Good Manufacturing Practice' (GMP) standards. We replaced animal sera with human platelet lysates and used a novel type of tissue-culture ware. ECFCs cultured under the new conditions revealed significantly lower apoptosis and increased proliferation rates. Simultaneously, their viability was increased. Since extensively expanded ECFCs could still settle on scaffold biomaterials and were able to form tubular structures in Matrigel assays, we conclude that these ex vivo-expanded ECFCs are a novel, very potent cell source for scaffold-based tissue engineering. Copyright © 2013 John Wiley & Sons, Ltd.

Vascular endothelial growth factor receptor 1 (VEGFR1) tyrosine kinase signaling facilitates granulation tissue formation with recruitment of VEGFR1+ cells from bone marrow.

PubMed

Park, Keiichi; Amano, Hideki; Ito, Yoshiya; Mastui, Yoshio; Kamata, Mariko; Yamazaki, Yasuharu; Takeda, Akira; Shibuya, Masabumi; Majima, Masataka

2018-06-01

Vascular endothelial growth factor (VEGF)-A facilitates wound healing. VEGF-A binds to VEGF receptor 1 (VEGFR1) and VEGFR2 and induces wound healing through the receptor's tyrosine kinase (TK) domain. During blood flow recovery and lung regeneration, expression of VEGFR1 is elevated. However, the precise mechanism of wound healing, especially granulation formation on VEGFR1, is not well understood. We hypothesized that VEGFR1-TK signaling induces wound healing by promoting granulation tissue formation. A surgical sponge implantation model was made by implanting a sponge disk into dorsal subcutaneous tissue of mice. Granulation formation was estimated from the weight of the sponge and the granulation area from the immunohistochemical analysis of collagen I. The expression of fibroblast markers was estimated from the expression of transforming growth factor-beta (TGF-β) and cellular fibroblast growth factor-2 (FGF-2) using real-time PCR (polymerase chain reaction) and from the immunohistochemical analysis of S100A4. VEGFR1 TK knockout (TK -/- ) mice exhibited suppressed granulation tissue formation compared to that in wild-type (WT) mice. Expression of FGF-2, TGF-β, and VEGF-A was significantly suppressed in VEGFR1 TK -/- mice, and the accumulation of VEGFR1 + cells in granulation tissue was reduced in VEGFR1 TK -/- mice compared to that in WT mice. The numbers of VEGFR1 + cells and S100A4 + cells derived from bone marrow (BM) were higher in WT mice transplanted with green fluorescent protein (GFP) transgenic WT BM than in VEGFR1 TK -/- mice transplanted with GFP transgenic VEGFR1 TK -/- BM. These results indicated that VEGFR1-TK signaling induced the accumulation of BM-derived VEGFR1 + cells expressing F4/80 and S100A4 and contributed to granulation formation around the surgically implanted sponge area in a mouse model.

Gene Electrotransfer of Plasmid with Tissue Specific Promoter Encoding shRNA against Endoglin Exerts Antitumor Efficacy against Murine TS/A Tumors by Vascular Targeted Effects.

PubMed

Stimac, Monika; Dolinsek, Tanja; Lampreht, Ursa; Cemazar, Maja; Sersa, Gregor

2015-01-01

Vascular targeted therapies, targeting specific endothelial cell markers, are promising approaches for the treatment of cancer. One of the targets is endoglin, transforming growth factor-β (TGF-β) co-receptor, which mediates proliferation, differentiation and migration of endothelial cells forming neovasculature. However, its specific, safe and long-lasting targeting remains the challenge. Therefore, in our study we evaluated the transfection efficacy, vascular targeted effects and therapeutic potential of the plasmid silencing endoglin with the tissue specific promoter, specific for endothelial cells marker endothelin-1 (ET) (TS plasmid), in comparison to the plasmid with constitutive promoter (CON plasmid), in vitro and in vivo. Tissue specificity of TS plasmid was demonstrated in vitro on several cell lines, and its antiangiogenic efficacy was demonstrated by reducing tube formation of 2H11 endothelial cells. In vivo, on a murine mammary TS/A tumor model, we demonstrated good antitumor effect of gene electrotransfer (GET) of either of both plasmids in treatment of smaller tumors still in avascular phase of growth, as well as on bigger tumors, already well vascularized. In support to the observations on predominantly vascular targeted effects of endoglin, histological analysis has demonstrated an increase in necrosis and a decrease in the number of blood vessels in therapeutic groups. A significant antitumor effect was observed in tumors in avascular and vascular phase of growth, possibly due to both, the antiangiogenic and the vascular disrupting effect. Furthermore, the study indicates on the potential use of TS plasmid in cancer gene therapy since the same efficacy as of CON plasmid was determined.

Standardizing Descemet Membrane Endothelial Keratoplasty Graft Preparation Method in the Eye Bank-Experience of 527 Descemet Membrane Endothelial Keratoplasty Tissues.

PubMed

Parekh, Mohit; Baruzzo, Mattia; Favaro, Elisa; Borroni, Davide; Ferrari, Stefano; Ponzin, Diego; Ruzza, Alessandro

2017-12-01

To share the experience and provide a standardized protocol for Descemet membrane endothelial keratoplasty (DMEK) graft preparation. A retrospective study based on 527 prestripped DMEK tissues that were prepared between 2014 and 2017. The experience of using different instruments and techniques has been described, and a standardized technique for preparing DMEK grafts has been identified. The tissues in general were prepared by superficially tapping the endothelial side with a Moria trephine (9.5 mm diameter). The plane of cleavage was identified using a cleavage hook, and the DMEK graft was deadhered from the trephined site throughout the circumference for ease of excising the graft. The DMEK graft was peeled using either one or multiple quadrant methods depending on the challenges faced during excision. The graft was finally marked with the letter "F" to identify the orientation during surgery. Data on endothelial cell loss (ECL) and challenging cases were observed, monitored, and recorded during this period. Less than 1 percent trypan blue-positive cells with tissue wastage of <6% was observed during the study period. Our standardized stripping technique has resulted in an overall ECL of 4.6%. Marking Descemet membrane showed 0.5% cell mortality. Standardizing DMEK technique using specific tools and simple techniques would help new surgeons to decide the instruments and improve their tissue preparation skills also in challenging cases such as previous cataract incisions or horseshoe-shaped tears, further reducing ECL or tissue wastage.

An adipoinductive role of inflammation in adipose tissue engineering: key factors in the early development of engineered soft tissues.

PubMed

Lilja, Heidi E; Morrison, Wayne A; Han, Xiao-Lian; Palmer, Jason; Taylor, Caroline; Tee, Richard; Möller, Andreas; Thompson, Erik W; Abberton, Keren M

2013-05-15

Tissue engineering and cell implantation therapies are gaining popularity because of their potential to repair and regenerate tissues and organs. To investigate the role of inflammatory cytokines in new tissue development in engineered tissues, we have characterized the nature and timing of cell populations forming new adipose tissue in a mouse tissue engineering chamber (TEC) and characterized the gene and protein expression of cytokines in the newly developing tissues. EGFP-labeled bone marrow transplant mice and MacGreen mice were implanted with TEC for periods ranging from 0.5 days to 6 weeks. Tissues were collected at various time points and assessed for cytokine expression through ELISA and mRNA analysis or labeled for specific cell populations in the TEC. Macrophage-derived factors, such as monocyte chemotactic protein-1 (MCP-1), appear to induce adipogenesis by recruiting macrophages and bone marrow-derived precursor cells to the TEC at early time points, with a second wave of nonbone marrow-derived progenitors. Gene expression analysis suggests that TNFα, LCN-2, and Interleukin 1β are important in early stages of neo-adipogenesis. Increasing platelet-derived growth factor and vascular endothelial cell growth factor expression at early time points correlates with preadipocyte proliferation and induction of angiogenesis. This study provides new information about key elements that are involved in early development of new adipose tissue.

Harnessing Sphingosine-1-Phosphate Signaling and Nanotopographical Cues To Regulate Skeletal Muscle Maturation and Vascularization.

PubMed

Tsui, Jonathan H; Janebodin, Kajohnkiart; Ieronimakis, Nicholas; Yama, David M P; Yang, Hee Seok; Chavanachat, Rakchanok; Hays, Aislinn L; Lee, Haeshin; Reyes, Morayma; Kim, Deok-Ho

2017-12-26

Despite possessing substantial regenerative capacity, skeletal muscle can suffer from loss of function due to catastrophic traumatic injury or degenerative disease. In such cases, engineered tissue grafts hold the potential to restore function and improve patient quality of life. Requirements for successful integration of engineered tissue grafts with the host musculature include cell alignment that mimics host tissue architecture and directional functionality, as well as vascularization to ensure tissue survival. Here, we have developed biomimetic nanopatterned poly(lactic-co-glycolic acid) substrates conjugated with sphingosine-1-phosphate (S1P), a potent angiogenic and myogenic factor, to enhance myoblast and endothelial maturation. Primary muscle cells cultured on these functionalized S1P nanopatterned substrates developed a highly aligned and elongated morphology and exhibited higher expression levels of myosin heavy chain, in addition to genes characteristic of mature skeletal muscle. We also found that S1P enhanced angiogenic potential in these cultures, as evidenced by elevated expression of endothelial-related genes. Computational analyses of live-cell videos showed a significantly improved functionality of tissues cultured on S1P-functionalized nanopatterns as indicated by greater myotube contraction displacements and velocities. In summary, our study demonstrates that biomimetic nanotopography and S1P can be combined to synergistically regulate the maturation and vascularization of engineered skeletal muscles.

"Deep-media culture condition" promoted lumen formation of endothelial cells within engineered three-dimensional tissues in vitro.

PubMed

Sekiya, Sachiko; Shimizu, Tatsuya; Yamato, Masayuki; Okano, Teruo

2011-03-01

In the field of tissue engineering, the induction of microvessels into tissues is an important task because of the need to overcome diffusion limitations of oxygen and nutrients within tissues. Powerful methods to create vessels in engineered tissues are needed for creating real living tissues. In this study, we utilized three-dimensional (3D) highly cell dense tissues fabricated by cell sheet technology. The 3D tissue constructs are close to living-cell dense tissue in vivo. Additionally, creating an endothelial cell (EC) network within tissues promoted neovascularization promptly within the tissue after transplantation in vivo. Compared to the conditions in vivo, however, common in vitro cell culture conditions provide a poor environment for creating lumens within 3D tissue constructs. Therefore, for determining adequate conditions for vascularizing engineered tissue in vitro, our 3D tissue constructs were cultured under a "deep-media culture conditions." Compared to the control conditions, the morphology of ECs showed a visibly strained cytoskeleton, and the density of lumen formation within tissues increased under hydrostatic pressure conditions. Moreover, the increasing expression of vascular endothelial cadherin in the lumens suggested that the vessels were stabilized in the stimulated tissues compared with the control. These findings suggested that deep-media culture conditions improved lumen formation in engineered tissues in vitro.

Signaling pathways effecting crosstalk between cartilage and adjacent tissues: Seminars in cell and developmental biology: The biology and pathology of cartilage.

PubMed

Maes, Christa

2017-02-01

Endochondral ossification, the mechanism responsible for the development of the long bones, is dependent on an extremely stringent coordination between the processes of chondrocyte maturation in the growth plate, vascular expansion in the surrounding tissues, and osteoblast differentiation and osteogenesis in the perichondrium and the developing bone center. The synchronization of these processes occurring in adjacent tissues is regulated through vigorous crosstalk between chondrocytes, endothelial cells and osteoblast lineage cells. Our knowledge about the molecular constituents of these bidirectional communications is undoubtedly incomplete, but certainly some signaling pathways effective in cartilage have been recognized to play key roles in steering vascularization and osteogenesis in the perichondrial tissues. These include hypoxia-driven signaling pathways, governed by the hypoxia-inducible factors (HIFs) and vascular endothelial growth factor (VEGF), which are absolutely essential for the survival and functioning of chondrocytes in the avascular growth plate, at least in part by regulating the oxygenation of developing cartilage through the stimulation of angiogenesis in the surrounding tissues. A second coordinating signal emanating from cartilage and regulating developmental processes in the adjacent perichondrium is Indian Hedgehog (IHH). IHH, produced by pre-hypertrophic and early hypertrophic chondrocytes in the growth plate, induces the differentiation of adjacent perichondrial progenitor cells into osteoblasts, thereby harmonizing the site and time of bone formation with the developmental progression of chondrogenesis. Both signaling pathways represent vital mediators of the tightly organized conversion of avascular cartilage into vascularized and mineralized bone during endochondral ossification. Copyright © 2016. Published by Elsevier Ltd.

Trophic factors from adipose tissue-derived multi-lineage progenitor cells promote cytodifferentiation of periodontal ligament cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sawada, Keigo; Takedachi, Masahide, E-mail: takedati@dent.osaka-u.ac.jp; Yamamoto, Satomi

Stem and progenitor cells are currently being investigated for their applicability in cell-based therapy for periodontal tissue regeneration. We recently demonstrated that the transplantation of adipose tissue-derived multi-lineage progenitor cells (ADMPCs) enhances periodontal tissue regeneration in beagle dogs. However, the molecular mechanisms by which transplanted ADMPCs induce periodontal tissue regeneration remain to be elucidated. In this study, trophic factors released by ADMPCs were examined for their paracrine effects on human periodontal ligament cell (HPDL) function. ADMPC conditioned medium (ADMPC-CM) up-regulated osteoblastic gene expression, alkaline phosphatase activity and calcified nodule formation in HPDLs, but did not significantly affect their proliferative response.more » ADMPCs secreted a number of growth factors, including insulin-like growth factor binding protein 6 (IGFBP6), hepatocyte growth factor and vascular endothelial growth factor. Among these, IGFBP6 was most highly expressed. Interestingly, the positive effects of ADMPC-CM on HPDL differentiation were significantly suppressed by transfecting ADMPCs with IGFBP6 siRNA. Our results suggest that ADMPCs transplanted into a defect in periodontal tissue release trophic factors that can stimulate the differentiation of HPDLs to mineralized tissue-forming cells, such as osteoblasts and cementoblasts. IGFBP6 may play crucial roles in ADMPC-induced periodontal regeneration. - Highlights: • ADMPC-derived humoral factors stimulate cytodifferentiation of HPDLs. • ADMPCs secret growth factors including IGFBP6, VEGF and HGF. • IGFBP6 is involved in the promotion effect of ADMPC-CM on HPDL cytodifferentiation.« less

Gelatin-based hydrogel for vascular endothelial growth factor release in peripheral nerve tissue engineering.

PubMed

Gnavi, S; di Blasio, L; Tonda-Turo, C; Mancardi, A; Primo, L; Ciardelli, G; Gambarotta, G; Geuna, S; Perroteau, I

2017-02-01

Hydrogels are promising materials in regenerative medicine applications, due to their hydrophilicity, biocompatibility and capacity to release drugs and growth factors in a controlled manner. In this study, biocompatible and biodegradable hydrogels based on blends of natural polymers were used in in vitro and ex vivo experiments as a tool for VEGF-controlled release to accelerate the nerve regeneration process. Among different candidates, the angiogenic factor VEGF was selected, since angiogenesis has been long recognized as an important and necessary step during tissue repair. Recent studies have pointed out that VEGF has a beneficial effect on motor neuron survival and Schwann cell vitality and proliferation. Moreover, VEGF administration can sustain and enhance the growth of regenerating peripheral nerve fibres. The hydrogel preparation process was optimized to allow functional incorporation of VEGF, while preventing its degradation and denaturation. VEGF release was quantified through ELISA assay, whereas released VEGF bioactivity was validated in human umbilical vein endothelial cells (HUVECs) and in a Schwann cell line (RT4-D6P2T) by assessing VEGFR-2 and downstream effectors Akt and Erk1/2 phosphorylation. Moreover, dorsal root ganglia explants cultured on VEGF-releasing hydrogels displayed increased neurite outgrowth, providing confirmation that released VEGF maintained its effect, as also confirmed in a tubulogenesis assay. In conclusion, a gelatin-based hydrogel system for bioactive VEGF delivery was developed and characterized for its applicability in neural tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

Tissue Engineering of the Corneal Endothelium: A Review of Carrier Materials

PubMed Central

Teichmann, Juliane; Valtink, Monika; Nitschke, Mirko; Gramm, Stefan; Funk, Richard H.W.; Engelmann, Katrin; Werner, Carsten

2013-01-01

Functional impairment of the human corneal endothelium can lead to corneal blindness. In order to meet the high demand for transplants with an appropriate human corneal endothelial cell density as a prerequisite for corneal function, several tissue engineering techniques have been developed to generate transplantable endothelial cell sheets. These approaches range from the use of natural membranes, biological polymers and biosynthetic material compositions, to completely synthetic materials as matrices for corneal endothelial cell sheet generation. This review gives an overview about currently used materials for the generation of transplantable corneal endothelial cell sheets with a special focus on thermo-responsive polymer coatings. PMID:24956190

Dental stem cells: a future asset of ocular cell therapy.

PubMed

Yam, Gary Hin-Fai; Peh, Gary Swee-Lim; Singhal, Shweta; Goh, Bee-Tin; Mehta, Jodhbir S

2015-11-10

Regenerative medicine using patient's own stem cells (SCs) to repair dysfunctional tissues is an attractive approach to complement surgical and pharmacological treatments for aging and degenerative disorders. Recently, dental SCs have drawn much attention owing to their accessibility, plasticity and applicability for regenerative use not only for dental, but also other body tissues. In ophthalmology, there has been increasing interest to differentiate dental pulp SC and periodontal ligament SC (PDLSC) towards ocular lineage. Both can commit to retinal fate expressing eye field transcription factors and generate rhodopsin-positive photoreceptor-like cells. This proposes a novel therapeutic alternative for retinal degeneration diseases. Moreover, as PDLSC shares similar cranial neural crest origin and proteoglycan secretion with corneal stromal keratoctyes and corneal endothelial cells, this offers the possibility of differentiating PDLSC to these corneal cell types. The advance could lead to a shift in the medical management of corneal opacities and endothelial disorders from highly invasive corneal transplantation using limited donor tissue to cell therapy utilizing autologous cells. This article provides an overview of dental SC research and the perspective of utilizing dental SCs for ocular regenerative medicine.

The effect of Setarud (IMOD(TM)) on angiogenesis in transplanted human ovarian tissue to nude mice.

PubMed

Hormozi, Maryam; Talebi, Saeed; Khorram Khorshid, Hamid Reza; Zarnani, Amir-Hassan; Kamali, Koorosh; Jeddi-Tehrani, Mahmood; Soltangoraee, Haleh; Akhondi, Mohammad Mehdi

2015-10-01

One of the promising methods in fertility preservation among women with cancer is cryopreservation of ovarian cortex but there are many drawbacks such as apoptosis and considerable reduction of follicular density in the transplanted ovary. One solution to reduce ischemic damage is enhancing angiogenesis after transplantation of ovarian cortex tissue. The aim of this study was to investigate the effect of Setarud, on angiogenesis in transplanted human ovarian tissue. In this case control study, twenty four nude mice were implanted subcutaneously, with human ovarian tissues, from four women. The mice were randomly divided into two groups (n=12): the experimental group was treated with Setarud, while control group received only vehicle. Each group was divided into three subgroups (n=4) based on the graft recovery days post transplantation (PT). The transplanted fragments were removed on days 2, 7, and 30 PT and the expression of Angiopoietin-1, Angiopoietin-2, and Vascular endothelial growth factor at both gene and protein levels and vascular density were studied in the grafted ovarian tissues. On the 2(nd) and 7(th) day PT, the level of Angiopoietin-1 gene expression in case group was significantly lower than that in control group, while the opposite results were obtained for Angiopoietin-2 and Vascular endothelial growth factor. These results were also confirmed at the protein level. The density of vessels in Setarud group elevated significantly on day 7 PT compared to pre-treatment state. Our results showed that administration of Setarud may stimulates angiogenesis in transplanted human ovarian tissues, although further researches are needed before a clear judgment is made.

The effect of Setarud (IMODTM) on angiogenesis in transplanted human ovarian tissue to nude mice

PubMed Central

Hormozi, Maryam; Talebi, Saeed; Khorram Khorshid, Hamid Reza; Zarnani, Amir-Hassan; Kamali, Koorosh; Jeddi-Tehrani, Mahmood; Soltangoraee, Haleh; Akhondi, Mohammad Mehdi

2015-01-01

Background: One of the promising methods in fertility preservation among women with cancer is cryopreservation of ovarian cortex but there are many drawbacks such as apoptosis and considerable reduction of follicular density in the transplanted ovary. One solution to reduce ischemic damage is enhancing angiogenesis after transplantation of ovarian cortex tissue. Objective: The aim of this study was to investigate the effect of Setarud, on angiogenesis in transplanted human ovarian tissue. Materials and Methods: In this case control study, twenty four nude mice were implanted subcutaneously, with human ovarian tissues, from four women. The mice were randomly divided into two groups (n=12): the experimental group was treated with Setarud, while control group received only vehicle. Each group was divided into three subgroups (n=4) based on the graft recovery days post transplantation (PT). The transplanted fragments were removed on days 2, 7, and 30 PT and the expression of Angiopoietin-1, Angiopoietin-2, and Vascular endothelial growth factor at both gene and protein levels and vascular density were studied in the grafted ovarian tissues. Results: On the 2nd and 7th day PT, the level of Angiopoietin-1 gene expression in case group was significantly lower than that in control group, while the opposite results were obtained for Angiopoietin-2 and Vascular endothelial growth factor. These results were also confirmed at the protein level. The density of vessels in Setarud group elevated significantly on day 7 PT compared to pre-treatment state. Conclusion: Our results showed that administration of Setarud may stimulates angiogenesis in transplanted human ovarian tissues, although further researches are needed before a clear judgment is made. PMID:26644788

Cell-Responsive Hydrogel for Encapsulation of Vascular Cells

PubMed Central

Kraehenbuehl, Thomas P.; Ferreira, Lino S.; Zammaretti, Prisca; Hubbell, Jeffrey A.; Langer, Robert

2014-01-01

The in vitro potential of a synthetic matrix metalloproteinase (MMP)-responsive polyethylene glycol) (PEG)-based hydrogel as a bioactive co-encapsulation system for vascular cells and a small bioactive peptide, thymosin β4 (Tp4), was examined. We show that the physical incorporation of Tβ4 in this bioactive matrix creates a three-dimensional (3D) environment conducive for human umbilical vein endothelial cell (HUVEC) adhesion, survival, migration and organization. Gels with entrapped Tβ4 increased the survival of HUVEC compared to gels without Tp4, and significantly up-regulated the endothelial genes vascular endothelial-cadherin and angiopoietin-2, whereas von Willebrand factor was significantly down-regulated. Incorporation of Tβ4 significantly increased MMP-2 and MMP-9 secretion of encapsulated HUVEC. The gel acts as a controlled Tβ4-release system, as MMP-2 and MMP-9 enzymes trigger the release. In addition, Tβ4 facilitated HUVEC attachment and induced vascular-like network formation upon the PEG-hydrogels. These MMP-responsive PEG-hydrogels may thus serve as controlled co-encapsulation system of vascular cells and bioactive factors for in situ regeneration of ischemic tissues. PMID:19500842

Reactive oxygen species' role in endothelial dysfunction by electron paramagnetic resonance

NASA Astrophysics Data System (ADS)

Wassall, Cynthia D.

The endothelium is a single layer of cells lining the arteries and is involved in many physiological reactions which are responsible for vascular tone. Free radicals are important participants in these chemical reactions in the endothelium. Here we quantify free radicals, ex vivo, in biological tissue with continuous wave electron paramagnetic resonance (EPR). In all of the experiments in this thesis, we use a novel EPR spin trapping technique that has been developed for tissue segments. EPR spin trapping is often considered the 'gold standard' in reactive oxygen species (ROS) detection because of its sensitivity and non-invasive nature. In all experiments, tissue was placed in physiological saline solution with 190-mM PBN (N-tert -butyl-α-phenylnitrone), 10% by volume dimethyl-sulphoxide (DMSO) for cryopreservation, and incubated in the dark for between 30 minutes up to 2 hours at 37°C while gently being stirred. Tissue and supernatant were then loaded into a syringe and frozen at -80°C until EPR analysis. In our experiments, the EPR spectra were normalized with respect to tissue volume. Conducting experiments at liquid nitrogen temperature leads to some experimental advantages. The freezing of the spin adducts renders them stable over a longer period, which allows ample time to analyze tissue samples for ROS. The dielectric constant of ice is greatly reduced over its liquid counterpart; this property of water enables larger sample volumes to be inserted into the EPR cavity without overloading it and leads to enhanced signal detection. Due to Maxwell-Boltzmann statistics, the population difference goes up as the temperature goes down, so this phenomenon enhances the signal intensity as well. With the 'gold standard' assertion in mind, we investigated whether slicing tissue to assay ROS that is commonly used in fluorescence experiments will show more free radical generation than tissue of a similar volume that remains unsliced. Sliced tissue exhibited a 76% increase in ROS generation; this implies that higher ROS concentrations in sliced tissue indicate extraneous ROS generation not associated with the ROS stimulus of interest. We also investigated the role of ROS in chronic flow overload (CFO). Elevation of shear stress that increases production of vascular ROS has not been well investigated. We hypothesize that CFO increases ROS production mediated in part by NADPH oxidase, which leads to endothelial dysfunction. ROS production increased threefold in response to CFO. The endothelium dependent vasorelaxation was compromised in the CFO group. Treatment with apocynin significantly reduced ROS production in the vessel wall, preserved endothelial function, and inhibited expressions of p22/p47phox and NOX2/NOX4. The present data implicate NADPH oxidase produced ROS and eNOS uncoupling in endothelial dysfunction at 1 wk of CFO. In further work, a swine right ventricular hypertrophy (RVH) model induced by pulmonary artery (PA) banding was used to study right coronary artery (RCA) endothelial function and ROS level. Endothelial function was compromised in RCA of RVH as attributed to insufficient endothelial nitric oxide synthase cofactor tetrahydrobiopterin. In conclusion, stretch due to outward remodeling of RCA during RVH (at constant wall shear stress), similar to vessel stretch in hypertension, appears to induce ROS elevation, endothelial dysfunction, and an increase in basal tone. Finally, although hypertension-induced vascular stiffness and dysfunction are well established in patients and animal models, we hypothesize that stretch or distension due to hypertension and outward expansion is the cause of endothelial dysfunction mediated by angiotensin II type 1 (AT1) receptor in coronary arteries. The expression and activation of AT1 receptor and the production of ROS were up regulated and endothelial function deteriorated in the RCA. The acute inhibition of AT1 receptor and NADPH oxidase partially restored the endothelial function. Stretch or distension activates the AT1 receptor which mediates ROS production; this collectively leads to endothelial dysfunction in coronary arteries.

Endocrine gland-derived vascular endothelial growth factor in rat pancreas: genetic expression and testosterone regulation.

PubMed

Morales, Angélica; Morimoto, Sumiko; Díaz, Lorenza; Robles, Guillermo; Díaz-Sánchez, Vicente

2008-05-01

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is an endothelial cell mitogen, expressed essentially in steroidogenic cells. Recently, the expression of EG-VEGF in normal human pancreas and pancreatic adenocarcinoma has been demonstrated. Epidemiologically, pancreatic carcinogenesis is more frequent in males than females, and given that androgen receptors and testosterone biotransformation have been described in pancreas, we hypothesized that testosterone could participate in the regulation of EG-VEGF expression. In this study, we investigated the regulation of EG-VEGF gene expression by testosterone in normal rat pancreatic tissue and rat insulinoma cells (RINm5F). Total RNA was extracted from rat pancreas and cultured cells. Gene expression was studied by real-time PCR and protein detection by immunohistochemistry. Serum testosterone was quantified by RIA. Results showed that EG-VEGF is expressed predominantly in pancreatic islets and vascular endothelium, as well as in RINm5F cells. EG-VEGF gene expression was lower in the pancreas of rats with higher testosterone serum levels. A similar effect that was reverted by flutamide was observed in testosterone-treated RINm5F cells. In summary, testosterone down-regulated EG-VEGF gene expression in rat pancreatic tissue and RINm5F cells. This effect could be mediated by the androgen receptor. To our knowledge, this is the first time that a direct effect of testosterone on EG-VEGF gene expression in rat pancreas and RINm5F cells is demonstrated.

Clinicopathologic and prognostic implications of progranulin in breast carcinoma.

PubMed

Li, Li-qin; Huang, Hui-lian; Ping, Jin-liang; Wang, Xiao-hong; Zhong, Jing; Dai, Li-cheng

2011-07-05

Progranulin is a newly discovered 88-kDa glycoprotein originally purified from the highly tumorigenic mouse teratoma-derived cell line PC. Its expression is closely correlated with the development and metastasis of several cancers. However, no immunohistochemical evidence currently exists to correlate progranulin expression with clinicopathologic features in breast carcinoma biopsies, and the role of progranulin as a new marker of metastatic risk and prognosis in breast cancer has not yet been studied. The aim of this study was to investigate the clinicopathologic and prognostic implications of progranulin expression in breast carcinoma and its correlation with tumor angiogenesis. Progranulin expression was determined immunohistochemically in 183 surgical specimens from patients with breast cancer and 20 tissue samples from breast fibroadenomas. The tumor angiogenesis-related biomarker, vascular endothelial growth factor was assayed and microvessel density was assessed by counting vascular endothelial cells in tumor tissues labeled with endoglin antibody. The relationship between progranulin expression and the clinicopathologic data were analyzed. Progranulin proteins were overexpressed in breast cancer. The level of progranulin expression was significantly correlated with tumor size (P = 0.004), lymph node metastasis (P < 0.001) and TNM staging (P < 0.001). High progranulin expression was associated with higher tumor angiogenesis, reflected by increased vascular endothelial growth factor expression (P < 0.001) and higher microvessel density (P = 0.002). Progranulin may be a valuable marker for assessing the metastasis and prognosis of breast cancer, and could provide the basis for new combination regimens with antiangiogenic activity.

A gene therapy induced emphysema model and the protective role of stem cells.

PubMed

Zarogoulidis, Paul; Hohenforst-Schmidt, Wolfgang; Huang, Haidong; Sahpatzidou, Despoina; Freitag, Lutz; Sakkas, Leonidas; Rapti, Aggeliki; Kioumis, Ioannis; Pitsiou, Georgia; Kouzi-Koliakos, Kokkona; Papamichail, Anna; Papaiwannou, Antonis; Tsiouda, Theodora; Tsakiridis, Kosmas; Porpodis, Konstantinos; Lampaki, Sofia; Organtzis, John; Gschwendtner, Andreas; Zarogoulidis, Konstantinos

2014-11-14

Chronic obstructive pulmonary disease presents with two different phenotypes: chronic bronchitis and emphysema with parenchymal destruction. Decreased expression of vascular endothelial growth factor and increased endothelial cell apoptosis are considered major factors for emphysema. Stem cells have the ability of vascular regeneration and function as a repair mechanism for the damaged endothelial cells. Currently, minimally invasive interventional procedures such as placement of valves, bio-foam or coils are performed in order to improve the disturbed mechanical function in emphysema patients. However, these procedures cannot restore functional lung tissue. Additionally stem cell instillation into the parenchyma has been used in clinical studies aiming to improve overall respiratory function and quality of life. In our current experiment we induced emphysema with a DDMC non-viral vector in BALBC mice and simultaneously instilled stem cells testing the hyposthesis that they might have a protective role against the development of emphysema. The mice were divided into four groups: a) control, b) 50.000 cells, c) 75.000 and d) 100.000 cells. Lung pathological findings revealed that all treatment groups had less damage compared to the control group. Additionally, we observed that emphysema lesions were less around vessels in an area of 10 μm. Our findings indicate that stem cell instillation can have a regenerative role if applied upon a tissue scaffold with vessel around. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_195.

Effects of Fe particle irradiation on human endothelial barrier structure and function

NASA Astrophysics Data System (ADS)

Sharma, Preety; Guida, Peter; Grabham, Peter

2014-07-01

Space travel involves exposure to biologically effective heavy ion radiation and there is consequently a concern for possible degenerative disorders in humans. A significant target for radiation effects is the microvascular system, which is crucial to healthy functioning of the tissues. Its pathology is linked to disrupted endothelial barrier function and is not only a primary event in a range of degenerative diseases but also an important influencing factor in many others. Thus, an assessment of the effects of heavy ion radiation on endothelial barrier function would be useful for estimating the risks of space travel. This study was aimed at understanding the effects of high LET Fe particles (1 GeV/n) and is the first investigation of the effects of charged particles on the function of the human endothelial barrier. We used a set of established and novel endpoints to assess barrier function after exposure. These include, trans-endothelial electrical resistance (TEER), morphological effects, localization of adhesion and cell junction proteins (in 2D monolayers and in 3D tissue models), and permeability of molecules through the endothelial barrier. A dose of 0.50 Gy was sufficient to cause a progressive reduction in TEER measurements that were significant 48 hours after exposure. Concurrently, there were morphological changes and a 14% loss of cells from monolayers. Gaps also appeared in the normally continuous cell-border localization of the tight junction protein - ZO-1 but not the Platelet endothelial cell adhesion molecule (PECAM-1) in both monolayers and in 3D vessel models. Disruption of barrier function was confirmed by increased permeability to 3 kDa and 10 kDa dextran molecules. A dose of 0.25 Gy caused no detectible change in cell number, morphology, or TEER, but did cause barrier disruption since there were gaps in the cell border localization of ZO-1 and an increased permeability to 3 kDa dextran. These results indicate that Fe particles potently have impact on human endothelial barrier function and represent a risk for degenerative diseases in the space environment.

A Pilot Study Linking Endothelial Injury in Lungs and Kidneys in Chronic Obstructive Pulmonary Disease

PubMed Central

Laucho-Contreras, Maria E.; Petersen, Hans; Bijol, Vanesa; Sholl, Lynette M.; Choi, Mary E.; Divo, Miguel; Pinto-Plata, Victor; Chetta, Alfredo; Tesfaigzi, Yohannes; Celli, Bartolomé R.

2017-01-01

Rationale: Patients with chronic obstructive pulmonary disease (COPD) frequently have albuminuria (indicative of renal endothelial cell injury) associated with hypoxemia. Objectives: To determine whether (1) cigarette smoke (CS)-induced pulmonary and renal endothelial cell injury explains the association between albuminuria and COPD, (2) CS-induced albuminuria is linked to increases in the oxidative stress–advanced glycation end products (AGEs) receptor for AGEs (RAGE) pathway, and (3) enalapril (which has antioxidant properties) limits the progression of pulmonary and renal injury by reducing activation of the AGEs–RAGE pathway in endothelial cells in both organs. Methods: In 26 patients with COPD, 24 ever-smokers without COPD, 32 nonsmokers who underwent a renal biopsy or nephrectomy, and in CS-exposed mice, we assessed pathologic and ultrastructural renal lesions, and measured urinary albumin/creatinine ratios, tissue oxidative stress levels, and AGEs and RAGE levels in pulmonary and renal endothelial cells. The efficacy of enalapril on pulmonary and renal lesions was assessed in CS-exposed mice. Measurements and Main Results: Patients with COPD and/or CS-exposed mice had chronic renal injury, increased urinary albumin/creatinine ratios, and increased tissue oxidative stress and AGEs-RAGE levels in pulmonary and renal endothelial cells. Treating mice with enalapril attenuated CS-induced increases in urinary albumin/creatinine ratios, tissue oxidative stress levels, endothelial cell AGEs and RAGE levels, pulmonary and renal cell apoptosis, and the progression of chronic renal and pulmonary lesions. Conclusions: Patients with COPD and/or CS-exposed mice have pulmonary and renal endothelial cell injury linked to increased endothelial cell AGEs and RAGE levels. Albuminuria could identify patients with COPD in whom angiotensin-converting enzyme inhibitor therapy improves renal and lung function by reducing endothelial injury. PMID:28085500

In Vitro Vascular Cell Adhesion and Proliferation on Alkaline Degraded Poly-lactic/glycolic Acid Polymers

DTIC Science & Technology

2002-04-01

implanted gr~itf often leads to intimal hyperplasia which has resulted in occlusion of the regenerated vascular tissue [1, 2]. Since an endothelial... fibrovascular tissue ingrowth [I]. Clearly, the inability of poly(lactic acid) containing polymers to promote sufficient endothelialization presents serious

Exosome-Like Vesicles Derived from Adipose Tissue Provide Biochemical Cues for Adipose Tissue Regeneration.

PubMed

Dai, Minjia; Yu, Mei; Zhang, Yan; Tian, Weidong

2017-11-01

There is an emerging need for soft tissue replacements in the field of reconstructive surgery for the treatment of congenital deformities, posttraumatic repair, and cancer rehabilitation. Previous studies have shown that the bioactive adipose tissue extract can induce adipogenesis without additional stem cells or growth factors. In this study, we innovatively investigated whether exosome-like vesicles derived from adipose tissue (ELV-AT) could direct stem cell differentiation and trigger adipose tissue regeneration. In vitro, ELV-AT can induce adipogenesis of adipose-derived stem cells and promote proliferation, migration, and angiogenic potential of the aorta endothelial cells. In vivo, ELV-AT were transplanted to a chamber on the back of nude mice and neoadipose tissues were formed. Our findings indicated that ELV-AT could be used as a cell-free therapeutic approach for adipose tissue regeneration.

Paracrine control of vascularization and neurogenesis by neurotrophins.

PubMed

Emanueli, Costanza; Schratzberger, Peter; Kirchmair, Rudolf; Madeddu, Paolo

2003-10-01

The neuronal system plays a fundamental role in the maturation of primitive embryonic vascular network by providing a paracrine template for blood vessel branching and arterial differentiation. Furthermore, postnatal vascular and neural regeneration cooperate in the healing of damaged tissue. Neurogenesis continues in adulthood although confined to specific brain regions. Following ischaemic insult, neural staminal cells contribute towards the healing process through the stimulation of neurogenesis and vasculogenesis. Evidence indicates that nerves and blood vessels exert a reciprocal control of their own growth by paracrine mechanisms. For instance, guidance factors, including vascular endothelial growth factor A (VEGF-A) and semaphorins, which share the ability of binding neuropilin receptors, play a pivotal role in the tridimensional growth pattern of arterial vessels and nerves. Animal models and clinical studies have demonstrated a role of VEGF-A in the pathogenesis of ischaemic and diabetic neuropathies. Further, supplementation with VEGF-A ameliorates neuronal recovery by exerting protective effects on nerves and stimulating reparative neovascularization. Human tissue kallikrein, a recently discovered angiogenic and arteriogenic factor, accelerates neuronal recovery by stimulating the growth of vasa nervorum. Conversely, the neurotrophin nerve growth factor, known to regulate neuronal survival and differentiation, is now regarded as a stimulator of angiogenesis and arteriogenesis. These results indicate that angiogenesis and neurogenesis are paracrinally regulated by growth factors released by endothelial cells and neurons. Supplementation of these growth factors, alone or in combination, could benefit the treatment of ischaemic diseases and neuropathies.

Regulation of vascular endothelial growth factor-C by tumor necrosis factor-α in the conjunctiva and pterygium.

PubMed

Dong, Yoko; Kase, Satoru; Dong, Zhenyu; Fukuhara, Junichi; Tagawa, Yoshiaki; Ishizuka, Erdal Tan; Murata, Miyuki; Shinmei, Yasuhiro; Ohguchi, Takeshi; Kanda, Atsuhiro; Noda, Kousuke; Ishida, Susumu

2016-08-01

Vascular endothelial growth factor C (VEGF-C) plays an important role in the development of a pterygium through lymphangiogenesis. We examined the association between VEGF-C and tumor necrosis factor-α (TNF-α) in the pathogenesis of pterygia. Cultured conjunctival epithelial cells were treated with TNF-α, and the gene expression levels of VEGFC were evaluated by quantitative polymerase chain reaction (qPCR) and VEGF-C protein expression levels were measured using an enzyme-linked immunosorbent assay (ELISA). In addition, using ELISA, we evaluated the VEGF-C protein expression in the supernatants of cultured conjunctival epithelial cells, in which we neutralized TNF-α using anti‑TNF-α antibody. The gene expression of tumor necrosis factor receptor superfamily, member 1A (TNFRSF1A), known as TNF receptor 1 (TNFR1), was confirmed using reverse transcription PCR in cultured conjunctival epithelial cells. Immunofluorescence microscopy was used to examine the localization of VEGF-C and TNFR1 in pterygium tissues and TNFR1 expression in cultured conjunctival epithelial cells. Immunohistochemistry was used to examine the localization of TNFR1 in pterygia and normal conjunctival tissues. VEGFC gene expression increased in cultured conjunctival epithelial cells 24 h after the addition of TNF-α. The secretion of VEGF-C protein was significantly increased 48 h after the stimulation of cultured conjunctival epithelial cells with TNF-α. Increased VEGF-C protein secretion stimulated by TNF-α was significantly reduced by anti-TNF-α neutralizing antibody treatment. In cultured conjunctival epithelial cells, TNFRSF1A and TNFR1 were expressed. TNFR1 was immunolocalized in normal conjunctival tissues and in human pterygium tissues as well as in VEGF‑C‑positive epithelial cells from human pterygia. Our data demonstrate that TNF-α mediates VEGF-C expression, which plays a critical role in the pathogenesis of pterygia.

Migration of bone marrow and cord blood mesenchymal stem cells in vitro is regulated by stromal-derived factor-1-CXCR4 and hepatocyte growth factor-c-met axes and involves matrix metalloproteinases.

PubMed

Son, Bo-Ra; Marquez-Curtis, Leah A; Kucia, Magda; Wysoczynski, Marcin; Turner, A Robert; Ratajczak, Janina; Ratajczak, Mariusz Z; Janowska-Wieczorek, Anna

2006-05-01

Human mesenchymal stem cells (MSCs) are increasingly being considered in cell-based therapeutic strategies for regeneration of various organs/tissues. However, the signals required for their homing and recruitment to injured sites are not yet fully understood. Because stromal-derived factor (SDF)-1 and hepatocyte growth factor (HGF) become up-regulated during tissue/organ damage, in this study we examined whether these factors chemoattract ex vivo-expanded MSCs derived from bone marrow (BM) and umbilical cord blood (CB). Specifically, we investigated the expression by MSCs of CXCR4 and c-met, the cognate receptors of SDF-1 and HGF, and their functionality after early and late passages of MSCs. We also determined whether MSCs express matrix metalloproteinases (MMPs), including membrane type 1 (MT1)-MMP, matrix-degrading enzymes that facilitate the trafficking of hematopoietic stem cells. We maintained expanded BM- or CB-derived MSCs for up to 15-18 passages with monitoring of the expression of 1) various tissue markers (cardiac and skeletal muscle, neural, liver, and endothelial cells), 2) functional CXCR4 and c-met, and 3) MMPs. We found that for up to 15-18 passages, both BM- and CB-derived MSCs 1) express mRNA for cardiac, muscle, neural, and liver markers, as well as the vascular endothelial (VE) marker VE-cadherin; 2) express CXCR4 and c-met receptors and are strongly attracted by SDF-1 and HGF gradients; 3) express MMP-2 and MT1-MMP transcripts and proteins; and 4) are chemo-invasive across the reconstituted basement membrane Matrigel. These in vitro results suggest that the SDF-1-CXCR4 and HGF-c-met axes, along with MMPs, may be involved in recruitment of expanded MSCs to damaged tissues.

Reactive Oxygen Species in Inflammation and Tissue Injury

PubMed Central

Mittal, Manish; Siddiqui, Mohammad Rizwan; Tran, Khiem; Reddy, Sekhar P.

2014-01-01

Abstract Reactive oxygen species (ROS) are key signaling molecules that play an important role in the progression of inflammatory disorders. An enhanced ROS generation by polymorphonuclear neutrophils (PMNs) at the site of inflammation causes endothelial dysfunction and tissue injury. The vascular endothelium plays an important role in passage of macromolecules and inflammatory cells from the blood to tissue. Under the inflammatory conditions, oxidative stress produced by PMNs leads to the opening of inter-endothelial junctions and promotes the migration of inflammatory cells across the endothelial barrier. The migrated inflammatory cells not only help in the clearance of pathogens and foreign particles but also lead to tissue injury. The current review compiles the past and current research in the area of inflammation with particular emphasis on oxidative stress-mediated signaling mechanisms that are involved in inflammation and tissue injury. Antioxid. Redox Signal. 20, 1126–1167. PMID:23991888

Novel culture system of mesenchymal stromal cells from human subcutaneous adipose tissue.

PubMed

Iwashima, Shigejiro; Ozaki, Takenori; Maruyama, Shoichi; Saka, Yousuke; Kobori, Masato; Omae, Kaoru; Yamaguchi, Hirotake; Niimi, Tomoaki; Toriyama, Kazuhiro; Kamei, Yuzuru; Torii, Shuhei; Murohara, Toyoaki; Yuzawa, Yukio; Kitagawa, Yasuo; Matsuo, Seiichi

2009-05-01

Accumulating evidence suggests that the delivery of human adipose tissue-derived stromal cells (hASCs) has great potential as regenerative therapy. This was performed to develop a method for expanding hASCs by reducing the amount of serum required. We demonstrate that hASCs were able to expand efficiently in media containing 2% serum and fibroblast growth factor-2. These cells, or low serum cultured hASCs (hLASCs), expressed cell surface markers similar to those on bone marrow-derived mesenchymal stem cells, and could be differentiated into cells of mesenchymal lineage. Of interest, hLASCs secreted higher levels of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) than hASCs cultured in 20% serum (hHASCs). Moreover, hLASC-conditioned media significantly increased endothelial cell (EC) proliferation and decreased EC apoptosis compared to that obtained from hHASCs or control media only. Antibodies against VEGF and HGF virtually negated these effects. When hASCs were administered into the ischemic hindlimbs of nude rats, hLASCs improved blood flow, increased capillary density, and raised the levels of VEGF and HGF in the muscles as compared with hHASCs. In conclusion, we demonstrate a novel low serum culture system for hASCs, which may have great potential in regenerative cell therapy for damaged organs in the clinical setting.

In Vitro Human Umbilical Vein Endothelial Cells Response to Ionic Dissolution Products from Lithium-Containing 45S5 Bioactive Glass

PubMed Central

Haro Durand, Luis A.; Vargas, Gabriela E.; Vera-Mesones, Rosa; Baldi, Alberto; Zago, María P.; Fanovich, María A.; Boccaccini, Aldo R.; Gorustovich, Alejandro

2017-01-01

Since lithium (Li+) plays roles in angiogenesis, the localized and controlled release of Li+ ions from bioactive glasses (BGs) represents a promising alternative therapy for the regeneration and repair of tissues with a high degree of vascularization. Here, microparticles from a base 45S5 BG composition containing (wt %) 45% SiO2, 24.5% Na2O, 24.5% CaO, and 6% P2O5, in which Na2O was partially substituted by 5% Li2O (45S5.5Li), were obtained. The results demonstrate that human umbilical vein endothelial cells (HUVECs) have greater migratory and proliferative response and ability to form tubules in vitro after stimulation with the ionic dissolution products (IDPs) of the 45S5.5Li BG. The results also show the activation of the canonical Wnt/β-catenin pathway and the increase in expression of proangiogenic cytokines insulin like growth factor 1 (IGF1) and transforming growth factor beta (TGFβ). We conclude that the IDPs of 45S5.5Li BG would act as useful inorganic agents to improve tissue repair and regeneration, ultimately stimulating HUVECs behavior in the absence of exogenous growth factors. PMID:28773103

PHD-2 Suppression in Mesenchymal Stromal Cells Enhances Wound Healing.

PubMed

Ko, Sae Hee; Nauta, Allison C; Morrison, Shane D; Hu, Michael S; Zimmermann, Andrew S; Chung, Michael T; Glotzbach, Jason P; Wong, Victor W; Walmsley, Graham G; Peter Lorenz, H; Chan, Denise A; Gurtner, Geoffrey C; Giaccia, Amato J; Longaker, Michael T

2018-01-01

Cell therapy with mesenchymal stromal cells is a promising strategy for tissue repair. Restoration of blood flow to ischemic tissues is a key step in wound repair, and mesenchymal stromal cells have been shown to be proangiogenic. Angiogenesis is critically regulated by the hypoxia-inducible factor (HIF) superfamily, consisting of transcription factors targeted for degradation by prolyl hydroxylase domain (PHD)-2. The aim of this study was to enhance the proangiogenic capability of mesenchymal stromal cells and to use these modified cells to promote wound healing. Mesenchymal stromal cells harvested from mouse bone marrow were transduced with short hairpin RNA (shRNA) against PHD-2; control cells were transduced with scrambled shRNA (shScramble) construct. Gene expression quantification, human umbilical vein endothelial cell tube formation assays, and wound healing assays were used to assess the effect of PHD knockdown mesenchymal stromal cells on wound healing dynamics. PHD-2 knockdown mesenchymal stromal cells overexpressed HIF-1α and multiple angiogenic factors compared to control (p < 0.05). Human umbilical vein endothelial cells treated with conditioned medium from PHD-2 knockdown mesenchymal stromal cells exhibited increased formation of capillary-like structures and enhanced migration compared with human umbilical vein endothelial cells treated with conditioned medium from shScramble-transduced mesenchymal stromal cells (p < 0.05). Wounds treated with PHD-2 knockdown mesenchymal stromal cells healed at a significantly accelerated rate compared with wounds treated with shScramble mesenchymal stromal cells (p < 0.05). Histologic studies revealed increased blood vessel density and increased cellularity in the wounds treated with PHD-2 knockdown mesenchymal stromal cells (p < 0.05). Silencing PHD-2 in mesenchymal stromal cells augments their proangiogenic potential in wound healing therapy. This effect appears to be mediated by overexpression of HIF family transcription factors and up-regulation of multiple downstream angiogenic factors.

Localization of matrix metalloproteinases, (MMPs) their tissue inhibitors, and vascular endothelial growth factor (VEGF) in growth plates of children and adolescents indicates a role for MMPs in human postnatal growth and skeletal maturation.

PubMed

Haeusler, G; Walter, I; Helmreich, M; Egerbacher, M

2005-05-01

Numerous studies have focused on the expression, regulation, and biological significance of matrix metalloproteinases (MMPs) in the growth plate. Findings in mouse knockout models and in vitro data from various species indicate that MMPs not only degrade extracellular matrix components but may regulate the activity of local growth factors. In this study we investigated the presence, distribution, and activity of various MMPs and inhibitors, tissue transglutaminase (tTG or TG2) and vascular endothelial growth factor (VEGF) in the human child and adolescent growth plates by means of immunohistochemistry and gelatin zymography. Tissue was derived during orthopedic surgery (epiphysiodesis) in two prepubertal and four pubertal patients.MMP-2 and MMP-14 were present in reserve cell chondrocytes. MMP-14 was the most prominent MMP within all zones of the growth plate including proliferating chondrocytes. MMP-1 and MMP-13 (collagenases 1 and 3), MMP-9 (gelatinases B), MMP-10, and MMP-11 (stromelysins) and VEGF were positive in hypertrophic chondrocytes and osteoblasts. MMP-2 showed the same expression pattern but was negative in osteoblasts. Osteoclasts stained positive for MMP-9, MMP-2, and TG2. Tissue inhibitor of MMP (TIMP)-1 was present in all zones of the growth plate, osteoblasts, and osteoclasts; TIMP-2 was found in hypertrophic chondrocytes and osteoblasts. In summary, the presence of MMPs, TIMPs, TG2, and VEGF in our study indicated that the MMPs are relevant in growth plate physiology during the postnatal period in humans. The specific location of MMP expression within the growth plate may be the basis for further studies on the role of MMPs in the local regulation of chondrocyte differentiation, proliferation, and ossification at the chondroosseus junction.

Angiogenesis and Vascular Architecture in Pheochromocytomas

PubMed Central

Favier, Judith; Plouin, Pierre-François; Corvol, Pierre; Gasc, Jean-Marie

2002-01-01

Angiogenesis is a critical step in tumor growth and metastatic invasion. We here report the study of the vascular status of 10 benign and 9 malignant pheochromocytomas. We examined the vascular architecture after immunostaining endothelial cells (CD34) and vascular smooth muscle cells (α-actin) and identified a vascular pattern characteristic of malignant lesions. To define a gene expression profile indicative of the invasive phenotype, we studied by in situ hybridization the expression of genes encoding several pro- and anti-angiogenic factors [hypoxia-inducible factor (HIF-1α), EPAS1, vascular endothelial growth factor (VEGF), VEGF receptors, angiopoietins and their receptor Tie2, five genes of the endothelin system, and thrombospondin 1]. A semiquantitative evaluation of the labeling revealed an induction of genes encoding EPAS1, VEGF, VEGFR-1, VEGFR-2, endothelin receptor, type B (ETB) and endothelin receptor, type A (ETA) in malignant pheochromocytomas as compared to benign tumors. These differences were observed in tumor cells, in endothelial cells, or in both. Quantification by real-time reverse-transcriptase polymerase chain reaction showed an increase of EPAS1, VEGF, and ETB transcripts of 4.5-, 3.5-, and 10-fold, respectively, in malignant versus benign tumors. Furthermore, we observed a strong correlation between the expression of EPAS1 and VEGF in tumoral tissue and between EPAS1 and ETB in endothelial cells. Altogether, our observations show that analysis of angiogenesis provides promising new criteria for the diagnosis of malignant pheochromocytomas. PMID:12368197

Co-Culture of Human Endothelial Cells and Foreskin Fibroblasts on 3D Silk-Fibrin Scaffolds Supports Vascularization.

PubMed

Samal, Juhi; Weinandy, Stefan; Weinandy, Agnieszka; Helmedag, Marius; Rongen, Lisanne; Hermanns-Sachweh, Benita; Kundu, Subhas C; Jockenhoevel, Stefan

2015-10-01

A successful strategy to enhance the in vivo survival of engineered tissues would be to prevascularize them. In this study, fabricated silk fibroin scaffolds from mulberry and non-mulberry silkworms are investigated and compared for supporting the co-culture of human umbilical vein endothelial cells and human foreskin fibroblasts. Scaffolds are cytocompatible and when combined with fibrin gel support capillary-like structure formation. Density and interconnectivity of the formed structures are found to be better in mulberry scaffolds. ELISA shows that levels of vascular endothelial growth factor (VEGF) released in co-cultures with fibrin gel are significantly higher than in co-cultures without fibrin gel. RT PCR shows an increase in VEGFR2 expression in mulberry scaffolds indicating these scaffolds combined with fibrin provide a suitable microenvironment for the development of capillary-like structures. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Stem cells derived from tooth periodontal ligament enhance functional angiogenesis by endothelial cells.

PubMed

Yeasmin, Shamima; Ceccarelli, Jacob; Vigen, Marina; Carrion, Bita; Putnam, Andrew J; Tarle, Susan A; Kaigler, Darnell

2014-04-01

In regenerative medicine approaches involving cell therapy, selection of the appropriate cell type is important in that the cells must directly (differentiation) or indirectly (trophic effects) participate in the regenerative response. Regardless of the mode of action of the cells, angiogenesis underlies the success of these approaches. Stem cells derived from tooth tissues, specifically the periodontal ligament of teeth (periodontal ligament stem cells [PDLSCs]), have recently been identified as a good source of multipotent cells for cell therapies. PDLSCs have demonstrated properties similar to mesenchymal stem cells (MSCs), yet, unlike MSCs, their vascular potential has not been previously demonstrated. Thus, the aim of this study was to determine if PDLSCs could modulate angiogenesis. In comparison to MSCs and stem cells derived from tooth pulp tissues (SHEDs), we first determined if PDLSCs released soluble proangiogenic factors with the capacity to induce vessel formation by endothelial cells (ECs). Next, the ability of PDLSCs to modulate angiogenesis was examined through their cotransplantation with ECs in subcutaneous sites of immunocompromised mice. Finally, the stability of the PDLSC-mediated vasculature was determined through evaluation of the maturity and functionality of the vessels formed following PDLSC transplantation. It was determined that PDLSCs produced appreciable levels of vascular endothelial growth factor and basic fibroblast growth factor-2, and additionally, were able to initiate in vitro angiogenesis of ECs comparable to MSC- and SHED-mediated angiogenesis. In vivo cotransplantation of ECs with PDLSCs significantly (>50% increase) enhanced the number of blood vessels formed relative to transplantation of ECs alone. Finally, vessels formed following PDLSC cotransplantation were more mature and less permeable than those formed after transplantation of EC alone. These data demonstrate for the first time that PDLSCs have vascular potential, which could make them a very attractive cell population for utilization in regenerative cell therapies.

α-Naphthoflavone Increases Lipid Accumulation in Mature Adipocytes and Enhances Adipocyte-Stimulated Endothelial Tube Formation.

PubMed

Wang, Mei-Lin; Lin, Shyh-Hsiang; Hou, Yuan-Yu; Chen, Yue-Hwa

2015-04-30

The aryl hydrocarbon receptor (AhR) is a ligand-activated factor that regulates biological effects associated with obesity. The AhR agonists, such as environmental contaminants 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and β-naphthoflavone (BNF), inhibit preadipocyte differentiation and interfere with the functions of adipose tissue, whereas the antagonist may have opposite or protective effects in obesity. This study investigated the effects of α-naphthoflavone (α-NF), an AhR antagonist, on adipogenesis- and angiogenesis-associated factors in mature adipocytes and on cross-talk of mature adipocytes with endothelial cells (ECs). Besides, the roles of the AhR on lipid accumulation and on secretion of vascular endothelial growth factor were also determined by introducing siRNA of AhR. Differentiated 3T3-L1 cells were treated with α-naphthoflavone (α-NF) (1-5 μM) for 16 h. Lipid accumulation and the expressions of AhR-associated factors in the cells were determined. The interaction between adipocytes and ECs was investigated by cultivating ECs with conditioned medium (CM) from α-NF-treated mature adipocytes, followed by the determination of endothelial tube formation. The results showed that α-NF significantly increased triglyceride (TG) accumulation in mature adipocytes, which was associated with increased expression of hormone-sensitive lipase (HSL), estrogen receptor (ER), as well as decreased expression of AhR, AhR nuclear translocator (ARNT), cytochrome P4501B1 (CYP1B1), and nuclear factor erythroid-2-related factor (NRF-2) proteins. In addition, CM stimulated formation of tube-like structures in ECs, and α-NF further enhanced such stimulation in association with modulated the secretions of various angiogenic mediators by mature adipocytes. Similarly, increased TG accumulation and vascular endothelial growth factor (VEGF) secretion were observed in AhR-knockout cells. In conclusion, α-NF increased TG accumulation in mature adipocytes and enhanced mature adipocyte-stimulated tube formation in ECs, suggesting that the AhR may suppress obesity-induced adverse effects, and α-NF abolished the protective effects of the AhR.

Induction of angiogenesis in tissue-engineered scaffolds designed for bone repair: a combined gene therapy-cell transplantation approach.

PubMed

Jabbarzadeh, Ehsan; Starnes, Trevor; Khan, Yusuf M; Jiang, Tao; Wirtel, Anthony J; Deng, Meng; Lv, Qing; Nair, Lakshmi S; Doty, Steven B; Laurencin, Cato T

2008-08-12

One of the fundamental principles underlying tissue engineering approaches is that newly formed tissue must maintain sufficient vascularization to support its growth. Efforts to induce vascular growth into tissue-engineered scaffolds have recently been dedicated to developing novel strategies to deliver specific biological factors that direct the recruitment of endothelial cell (EC) progenitors and their differentiation. The challenge, however, lies in orchestration of the cells, appropriate biological factors, and optimal factor doses. This study reports an approach as a step forward to resolving this dilemma by combining an ex vivo gene transfer strategy and EC transplantation. The utility of this approach was evaluated by using 3D poly(lactide-co-glycolide) (PLAGA) sintered microsphere scaffolds for bone tissue engineering applications. Our goal was achieved by isolation and transfection of adipose-derived stromal cells (ADSCs) with adenovirus encoding the cDNA of VEGF. We demonstrated that the combination of VEGF releasing ADSCs and ECs results in marked vascular growth within PLAGA scaffolds. We thereby delineate the potential of ADSCs to promote vascular growth into biomaterials.

Induction of angiogenesis in tissue-engineered scaffolds designed for bone repair: A combined gene therapy–cell transplantation approach

PubMed Central

Jabbarzadeh, Ehsan; Starnes, Trevor; Khan, Yusuf M.; Jiang, Tao; Wirtel, Anthony J.; Deng, Meng; Lv, Qing; Nair, Lakshmi S.; Doty, Steven B.; Laurencin, Cato T.

2008-01-01

One of the fundamental principles underlying tissue engineering approaches is that newly formed tissue must maintain sufficient vascularization to support its growth. Efforts to induce vascular growth into tissue-engineered scaffolds have recently been dedicated to developing novel strategies to deliver specific biological factors that direct the recruitment of endothelial cell (EC) progenitors and their differentiation. The challenge, however, lies in orchestration of the cells, appropriate biological factors, and optimal factor doses. This study reports an approach as a step forward to resolving this dilemma by combining an ex vivo gene transfer strategy and EC transplantation. The utility of this approach was evaluated by using 3D poly(lactide-co-glycolide) (PLAGA) sintered microsphere scaffolds for bone tissue engineering applications. Our goal was achieved by isolation and transfection of adipose-derived stromal cells (ADSCs) with adenovirus encoding the cDNA of VEGF. We demonstrated that the combination of VEGF releasing ADSCs and ECs results in marked vascular growth within PLAGA scaffolds. We thereby delineate the potential of ADSCs to promote vascular growth into biomaterials. PMID:18678895

Direct 3D bioprinting of prevascularized tissue constructs with complex microarchitecture

PubMed Central

Zhu, Wei; Qu, Xin; Zhu, Jie; Ma, Xuanyi; Patel, Sherrina; Liu, Justin; Wang, Pengrui; Lai, Cheuk Sun Edwin; Gou, Maling; Xu, Yang; Zhang, Kang; Chen, Shaochen

2017-01-01

Living tissues rely heavily on vascular networks to transport nutrients, oxygen and metabolic waste. However, there still remains a need for a simple and efficient approach to engineer vascularized tissues. Here, we created prevascularized tissues with complex three-dimensional (3D) microarchitectures using a rapid bioprinting method – microscale continuous optical bioprinting (μCOB). Multiple cell types mimicking the native vascular cell composition were encapsulated directly into hydrogels with precisely controlled distribution without the need of sacrificial materials or perfusion. With regionally controlled biomaterial properties the endothelial cells formed lumen-like structures spontaneously in vitro. In vivo implantation demonstrated the survival and progressive formation of the endothelial network in the prevascularized tissue. Anastomosis between the bioprinted endothelial network and host circulation was observed with functional blood vessels featuring red blood cells. With the superior bioprinting speed, flexibility and scalability, this new prevascularization approach can be broadly applicable to the engineering and translation of various functional tissues. PMID:28192772

Direct 3D bioprinting of prevascularized tissue constructs with complex microarchitecture.

PubMed

Zhu, Wei; Qu, Xin; Zhu, Jie; Ma, Xuanyi; Patel, Sherrina; Liu, Justin; Wang, Pengrui; Lai, Cheuk Sun Edwin; Gou, Maling; Xu, Yang; Zhang, Kang; Chen, Shaochen

2017-04-01

Living tissues rely heavily on vascular networks to transport nutrients, oxygen and metabolic waste. However, there still remains a need for a simple and efficient approach to engineer vascularized tissues. Here, we created prevascularized tissues with complex three-dimensional (3D) microarchitectures using a rapid bioprinting method - microscale continuous optical bioprinting (μCOB). Multiple cell types mimicking the native vascular cell composition were encapsulated directly into hydrogels with precisely controlled distribution without the need of sacrificial materials or perfusion. With regionally controlled biomaterial properties the endothelial cells formed lumen-like structures spontaneously in vitro. In vivo implantation demonstrated the survival and progressive formation of the endothelial network in the prevascularized tissue. Anastomosis between the bioprinted endothelial network and host circulation was observed with functional blood vessels featuring red blood cells. With the superior bioprinting speed, flexibility and scalability, this new prevascularization approach can be broadly applicable to the engineering and translation of various functional tissues. Copyright © 2017 Elsevier Ltd. All rights reserved.

Jaceosidin, a natural flavone, promotes angiogenesis via activation of VEGFR2/FAK/PI3K/AKT/NF-κB signaling pathways in endothelial cells.

PubMed

Lee, Tae Hoon; Jung, Hana; Park, Keun Hyung; Bang, Myun Ho; Baek, Nam-In; Kim, Jiyoung

2014-10-01

Angiogenesis, the growth of new blood vessels from pre-existing vasculature, plays an important role in physiological and pathological processes such as embryonic development wound healing and revascularization of tissues after exposure to ischemia. We investigated the effects of jaceosidin, a main constituent of medicinal herbs of the genus Artemisia, on angiogenesis and signaling pathways in endothelial cells. Jaceosidin stimulated proliferation, migration and tubulogenesis of ECs as well as ex vivo sprouting from aorta rings, which are phenomena typical of angiogenesis. Jaceosidin activated vascular endothelial growth factor receptor 2 (VEGFR2, FLk-1/KDR) and angiogenic signaling molecules such as focal adhesion kinase, phosphatidylinositol 3-kinase, and its downstream target, the serine-threonine kinase AKTWe also demonstrated that jaceosidin activated the NF-κB-driven expression of a luciferase reporter gene and NF-κB binding to DNA. Jaceosidin-induced proliferation and migration of human umbilical vascular endothelial cells were strongly inhibited by the phosphatidylinositol 3-kinase inhibitor LY294002 and NF-κB inhibitor BAY11-7082, indicating that the PI3K/AKT/NF-κB signaling pathway is involved in jaceosidin-induced angiogenesis. Our results suggest that jaceosidin stimulates angiogenesis by activating the VEGFR2/FAK/PI3K/AKT/NF-κB signaling pathway and that it may be useful in developing angiogenic agents to promote the growth of collateral blood vessels in ischemic tissues. © 2014 by the Society for Experimental Biology and Medicine.

Human endothelial precursor cells express tumor endothelial marker 1/endosialin/CD248.

PubMed

Bagley, Rebecca G; Rouleau, Cecile; St Martin, Thia; Boutin, Paula; Weber, William; Ruzek, Melanie; Honma, Nakayuki; Nacht, Mariana; Shankara, Srinivas; Kataoka, Shiro; Ishida, Isao; Roberts, Bruce L; Teicher, Beverly A

2008-08-01

Angiogenesis occurs during normal physiologic processes as well as under pathologic conditions such as tumor growth. Serial analysis of gene expression profiling revealed genes [tumor endothelial markers (TEM)] that are overexpressed in tumor endothelial cells compared with normal adult endothelial cells. Because blood vessel development of malignant tumors under certain conditions may include endothelial precursor cells (EPC) recruited from bone marrow, we investigated TEM expression in EPC. The expression of TEM1 or endosialin (CD248) and other TEM has been discovered in a population of vascular endothelial growth factor receptor 2+/CD31+/CD45-/VE-cadherin+ EPC derived from human CD133+/CD34+ cells. EPC share some properties with fully differentiated endothelial cells from normal tissue, yet reverse transcription-PCR and flow cytometry reveal that EPC express higher levels of endosialin at the molecular and protein levels. The elevated expression of endosialin in EPC versus mature endothelial cells suggests that endosialin is involved in the earlier stages of tumor angiogenesis. Anti-endosialin antibodies inhibited EPC migration and tube formation in vitro. In vivo, immunohistochemistry indicated that human EPC continued to express endosialin protein in a Matrigel plug angiogenesis assay established in nude mice. Anti-endosialin antibodies delivered systemically at 25 mg/kg were also able to inhibit circulating murine EPC in nude mice bearing s.c. SKNAS tumors. EPC and bone marrow-derived cells have been shown previously to incorporate into malignant blood vessels in some instances, yet they remain controversial in the field. The data presented here on endothelial genes that are up-regulated in tumor vasculature and in EPC support the hypothesis that the angiogenesis process in cancer can involve EPC.

Neurotrophins promote revascularization by local recruitment of TrkB+ endothelial cells and systemic mobilization of hematopoietic progenitors

PubMed Central

Kermani, Pouneh; Rafii, Dahlia; Jin, David K.; Whitlock, Paul; Schaffer, Wendy; Chiang, Anne; Vincent, Loic; Friedrich, Matthias; Shido, Koji; Hackett, Neil R.; Crystal, Ronald G.; Rafii, Shahin; Hempstead, Barbara L.

2005-01-01

The neurotrophin brain-derived neurotrophic factor (BDNF) is required for the maintenance of cardiac vessel wall stability during embryonic development through direct angiogenic actions on endothelial cells expressing the tropomysin receptor kinase B (TrkB). However, the role of BDNF and a related neurotrophin ligand, neurotrophin-4 (NT-4), in the regulation of revascularization of the adult tissues is unknown. To study the potential angiogenic capacity of BDNF in mediating the neovascularization of ischemic and non-ischemic adult mouse tissues, we utilized a hindlimb ischemia and a subcutaneous Matrigel model. Recruitment of endothelial cells and promotion of channel formation within the Matrigel plug by BDNF and NT-4 was comparable to that induced by VEGF-A. The introduction of BDNF into non-ischemic ears or ischemic limbs induced neoangiogenesis, with a 2-fold increase in the capillary density. Remarkably, treatment with BDNF progressively increased blood flow in the ischemic limb over 21 days, similar to treatment with VEGF-A. The mechanism by which BDNF enhances capillary formation is mediated in part through local activation of the TrkB receptor and also by recruitment of Sca-1+CD11b+ pro-angiogenic hematopoietic cells. BDNF induces a potent direct chemokinetic action on subsets of marrow-derived Sca-1+ hematopoietic cells co-expressing TrkB. These studies suggest that local regional delivery of BDNF may provide a novel mechanism for inducing neoangiogenesis through both direct actions on local TrkB-expressing endothelial cells in skeletal muscle and recruitment of specific subsets of TrkB+ bone marrow–derived hematopoietic cells to provide peri-endothelial support for the newly formed vessels. PMID:15765148

Cannabinoids inhibit angiogenic capacities of endothelial cells via release of tissue inhibitor of matrix metalloproteinases-1 from lung cancer cells.

PubMed

Ramer, Robert; Fischer, Sascha; Haustein, Maria; Manda, Katrin; Hinz, Burkhard

2014-09-15

Cannabinoids inhibit tumor neovascularization as part of their tumorregressive action. However, the underlying mechanism is still under debate. In the present study the impact of cannabinoids on potential tumor-to-endothelial cell communication conferring anti-angiogenesis was studied. Cellular behavior of human umbilical vein endothelial cells (HUVEC) associated with angiogenesis was evaluated by Boyden chamber, two-dimensional tube formation and fibrin bead assay, with the latter assessing three-dimensional sprout formation. Viability was quantified by the WST-1 test. Conditioned media (CM) from A549 lung cancer cells treated with cannabidiol, Δ(9)-tetrahydrocannabinol, R(+)-methanandamide or the CB2 agonist JWH-133 elicited decreased migration as well as tube and sprout formation of HUVEC as compared to CM of vehicle-treated cancer cells. Inhibition of sprout formation was further confirmed for cannabinoid-treated A549 cells co-cultured with HUVEC. Using antagonists to cannabinoid-activated receptors the antimigratory action was shown to be mediated via cannabinoid receptors or transient receptor potential vanilloid 1. SiRNA approaches revealed a cannabinoid-induced expression of tissue inhibitor of matrix metalloproteinases-1 (TIMP-1) as well as its upstream trigger, the intercellular adhesion molecule-1, to be causally linked to the observed decrease of HUVEC migration. Comparable anti-angiogenic effects were not detected following direct exposure of HUVEC to cannabinoids, but occurred after addition of recombinant TIMP-1 to HUVEC. Finally, antimigratory effects were confirmed for CM of two other cannabinoid-treated lung cancer cell lines (H460 and H358). Collectively, our data suggest a pivotal role of the anti-angiogenic factor TIMP-1 in intercellular tumor-endothelial cell communication resulting in anti-angiogenic features of endothelial cells. Copyright © 2014 Elsevier Inc. All rights reserved.

Autologous human plasma in stem cell culture and cryopreservation in the creation of a tissue-engineered vascular graft.

PubMed

Zhang, Ping; Policha, Aleksandra; Tulenko, Thomas; DiMuzio, Paul

2016-03-01

Previous work demonstrated the effectiveness of autologous adipose-derived stem cells (ASCs) as endothelial cell (EC) substitutes in vascular tissue engineering. We further this work toward clinical translation by evaluating ASC function after (1) replacement of fetal bovine serum (FBS) with autologous human plasma (HP) in culture and (2) cryopreservation. Human ASCs and plasma, isolated from periumbilical fat and peripheral blood, respectively, were collected from the same donors. ASCs were differentiated in endothelial growth medium supplemented with FBS (2%) vs HP (2%). Proliferation was measured by growth curves and MTT assay. Endothelial differentiation was measured by quantitative polymerase chain reaction, assessment of acetylated low-density lipoprotein uptake, and cord formation after plating on Matrigel (BD Biosciences, San Jose, Calif). Similar studies were conducted before and after cryopreservation of ASCs and included assessment of cell retention on the luminal surface of a vascular graft. ASCs expanded in HP-supplemented medium showed (1) similar proliferation to FBS-cultured ASCs, (2) consistent differentiation toward an EC lineage (increases in CD31, von Willebrand factor, and CD144 message; acetylated low-density lipoprotein uptake; and cord formation on Matrigel), and (3) retention on the luminal surface after seeding and subsequent flow conditioning. Cryopreservation did not significantly alter ASC viability, proliferation, acquisition of endothelial characteristics, or retention after seeding onto a vascular graft. This study suggests that (1) replacement of FBS with autologous HP--a step necessary for the translation of this technology into human use--does not significantly impair proliferation or endothelial differentiation of ASCs used as EC substitutes and (2) ASCs are tolerant to cryopreservation in terms of maintaining EC characteristics and retention on a vascular graft. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Estrogen receptor 1 (ESR1) regulates VEGFA in adipose tissue.

PubMed

Fatima, L A; Campello, R S; Santos, R de Souza; Freitas, H S; Frank, A P; Machado, U F; Clegg, D J

2017-12-01

Vascular endothelial growth factor A (VEGFA) is a key factor in the regulation of angiogenesis in adipose tissue. Poor vascularization during adipose tissue proliferation causes fibrosis and local inflammation, and is associated with insulin resistance. It is known that 17-beta estradiol (E2) regulates adipose tissue function and VEGFA expression in other tissues; however, the ability of E2 to regulate VEGFA in adipose tissue is currently unknown. In this study, we showed that, in 3T3-L1 cells, E2 and the estrogen receptor 1 (ESR1) agonist PPT induced VEGFA expression, while ESR1 antagonist (MPP), and selective knockdown of ESR1 using siRNA decreased VEGFA and prevented the ability of E2 to modulate its expression. Additionally, we found that E2 and PPT induced the binding of hypoxia inducible factor 1 alpha subunit (HIF1A) in the VEGFA gene promoter. We further found that VEGFA expression was lower in inguinal and gonadal white adipose tissues of ESR1 total body knockout female mice compared to wild type mice. In conclusion, our data provide evidence of an important role for E2/ESR1 in modulating adipose tissue VEGFA, which is potentially important to enhance angiogenesis, reduce inflammation and improve adipose tissue function.

Vitamin C restores healthy aging in a mouse model for Werner syndrome

PubMed Central

Massip, Laurent; Garand, Chantal; Paquet, Eric R.; Cogger, Victoria C.; O’Reilly, Jennifer N.; Tworek, Leslee; Hatherell, Avril; Taylor, Carla G.; Thorin, Eric; Zahradka, Peter; Le Couteur, David G.; Lebel, Michel

2013-01-01

Werner syndrome (WS) is a premature aging disorder caused by mutations in a RecQ-like DNA helicase. Mice lacking the helicase domain of the WRN homologue exhibit many phenotypic features of WS, including a prooxidant status and a shorter mean life span compared to wild-type animals. Here, we show that Wrn mutant mice also develop premature liver sinusoidal endothelial defenestration along with inflammation and metabolic syndrome. Vitamin C supplementation rescued the shorter mean life span of Wrn mutant mice and reversed several age-related abnormalities in adipose tissues and liver endothelial defenestration, genomic integrity, and inflammatory status. At the molecular level, phosphorylation of age-related stress markers like Akt kinase-specific substrates and the transcription factor NF-κB, as well as protein kinase Cδ and Hif-1α transcription factor levels, which are increased in the liver of Wrn mutants, were normalized by vitamin C. Vitamin C also increased the transcriptional regulator of lipid metabolism PPARα. Finally, microarray and gene set enrichment analyses on liver tissues revealed that vitamin C decreased genes normally up-regulated in human WS fibroblasts and cancers, and it increased genes involved in tissue injury response and adipocyte dedifferentiation in obese mice. Vitamin C did not have such effect on wild-type mice. These results indicate that vitamin C supplementation could be beneficial for patients with WS. PMID:19741171

Endothelial quality of pre-cut posterior corneal lamellae for Descemet membrane endothelial keratoplasty with a stromal rim (DMEK-S): two-year outcome of manual preparation in an ocular tissue bank.

PubMed

Krabcova, Ivana; Studeny, Pavel; Jirsova, Katerina

2013-06-01

To assess the quantitative and qualitative parameters of pre-cut posterior corneal lamellae for Descemet membrane endothelial keratoplasty with a stromal rim (DMEK-S) prepared manually in the Ocular Tissue Bank Prague. All 65 successfully prepared pre-cut posterior corneal lamellae provided for grafting during a 2-year period were analyzed retrospectively. The lamellae, consisting of a central zone of endothelium-Descemet membrane surrounded by a supporting peripheral stromal rim, were prepared manually from corneoscleral buttons having an endothelial cell density higher than 2,500 cells/mm(2). The live endothelial cell density, the percentage of dead cells, the hexagonality and the coefficient of variation were assessed before and immediately after preparation as well as after 2 days of organ culture storage at 31 °C. Altogether, the endothelium of 57 lamellae was assessed. Immediately after preparation, the mean live endothelial cell density was 2,835 cells/mm(2) and, on average, 1.8 % of dead cells were found. After 2 days of storage, the cell density decreased significantly to 2,757 cells/mm(2) and the percentage of dead cells to 1.0 %. There was a significant change in the mean hexagonality and the coefficient of variation after lamellar preparation and subsequent storage. The amount of tissue wasted during the preparation was 23 %. The endothelial cell density of posterior corneal lamellae sent for DMEK-S was higher than 2,700 cells/mm(2) in average with a low percentage of dead cells; 65 pre-cut tissues were used for grafting during a 2-year period.

Outcomes of Descemet Stripping Endothelial Keratoplasty Using Eye Bank-Prepared Preloaded Grafts.

PubMed

Palioura, Sotiria; Colby, Kathryn

2017-01-01

To evaluate the feasibility of Descemet stripping endothelial keratoplasty using grafts preloaded by an eye bank in a commercially available insertion device. In this retrospective case series, a series of 35 eyes in 34 consecutive patients who underwent Descemet stripping endothelial keratoplasty for Fuchs endothelial dystrophy or previously failed full-thickness grafts at a single tertiary care center from March 2013 to March 2014 was included. The donor tissue had undergone pre-lamellar dissection, trephination, and loading into EndoGlide Ultrathin inserters at the Lions Eye Institute for Transplant and Research (Tampa, FL) and was shipped overnight in Optisol GS to the surgeon (K.C.). Surgery was performed within 24 hours from tissue preparation and loading by the eye bank. Donor and recipient characteristics, endothelial cell density (ECD), best-corrected visual acuity, and central corneal thickness were recorded. The main outcome measures were intraoperative and postoperative complications and ECD loss at 3, 6, and 12 months. One primary graft failure (2.8%), 2 rebubblings (5.7%), and 1 graft rejection (2.8%) occurred. Mean preoperative donor ECD was 2821 ± 199 cells/mm. Six months postoperatively, the mean endothelial cell loss was 25.3% ± 17.2% (n = 32), which remained stable at 1 year (31.5% ± 17.9%, n = 32). Mean best-corrected visual acuity improved from 20/100 preoperatively to 20/25 at a mean follow-up of 1 year (n = 32). Mean central corneal thickness was reduced from 711 ± 110 μm to 638 ± 66 μm at the last follow-up visit. Donor graft tissue preloaded by an eye bank can be used successfully for endothelial keratoplasty. Preloading reduces intraoperative tissue manipulation.

Angiogenic effect of the aqueous extract of Cynodon dactylon on human umbilical vein endothelial cells and granulation tissue in rat.

PubMed

Soraya, Hamid; Moloudizargari, Milad; Aghajanshakeri, Shahin; Javaherypour, Soheil; Mokarizadeh, Aram; Hamedeyazdan, Sanaz; Esmaeli Gouvarchin Ghaleh, Hadi; Mikaili, Peyman; Garjani, Alireza

2015-01-29

Cynodon dactylon, a valuable medicinal plant, is widely used in Iranian folk medicine for the treatment of various cardiovascular diseases such as heart failure and atherosclerosis. Moreover, its anti-diabetic, anti-cancer and anti-microbial properties have been also reported. Concerning the critical role of angiogenesis in the incidence and progression of tumors and also its protective role in cardiovascular diseases, we investigated the effects of the aqueous extract prepared from the rhizomes of C. dactylon on vascular endothelial growth factor (VEGF) expressions in Human Umbilical Vein Endothelial Cells (HUVECs) and also on angiogenesis in carrageenan induced air-pouch model in rats. In the air-pouch model, carrageenan was injected into an air-pouch on the back of the rats and following an IV injection of carmine red dye on day 6, granulation tissue was processed for the assessment of the dye content. Furthermore, in an in vitro study, angiogenic property of the extract was assessed through its effect on VEGF expression in HUVECs. Oral administration of 400 mg/kg/day of the extract significantly increased angiogenesis (p<0.05) and markedly decreased neutrophil (p<0.05) and total leukocyte infiltration (p<0.001) into the granulation tissues. Moreover, the extract increased the expression of total VEGF in HUVECs at a concentration of (100 μl/ml). The present study showed that the aqueous extract of C. dactylon promotes angiogenesis probably through stimulating VEGF expression.

Angiogenesis in calcium phosphate scaffolds by inorganic copper ion release.

PubMed

Barralet, Jake; Gbureck, Uwe; Habibovic, Pamela; Vorndran, Elke; Gerard, Catherine; Doillon, Charles J

2009-07-01

Angiogenesis in a tissue-engineered device may be induced by incorporating growth factors (e.g., vascular endothelial growth factor [VEGF]), genetically modified cells, and=or vascular cells. It represents an important process during the formation and repair of tissue and is essential for nourishment and supply of reparative and immunological cells. Inorganic angiogenic factors, such as copper ions, are therefore of interest in the fields of regenerative medicine and tissue engineering due to their low cost, higher stability, and potentially greater safety compared with recombinant proteins or genetic engineering approaches. The purpose of this study was to compare tissue responses to 3D printed macroporous bioceramic scaffolds implanted in mice that had been loaded with either VEGF or copper sulfate. These factors were spatially localized at the end of a single macropore some 7 mm from the surface of the scaffold. Controls without angiogenic factors exhibited only poor tissue growth within the blocks; in contrast, low doses of copper sulfate led to the formation of microvessels oriented along the macropore axis. Further, wound tissue ingrowth was particularly sensitive to the quantity of copper sulfate and was enhanced at specific concentrations or in combination with VEGF. The potential to accelerate and guide angiogenesis and wound healing by copper ion release without the expense of inductive protein(s) is highly attractive in the area of tissue-engineered bone and offers significant future potential in the field of regenerative biomaterials.

Mechanism of the protective effects of the combined treatment with rhynchophylla total alkaloids and sinapine thiocyanate against a prothrombotic state caused by vascular endothelial cell inflammatory damage

PubMed Central

Li, Yunlun; Zhang, Xinya; Yang, Wenqing; Li, Chao; Chu, Yanjun; Jiang, Haiqiang; Shen, Zhenzhen

2017-01-01

The aim of the present study was to investigate the effect and the underlying mechanism of the combined treatment of rhynchophylla total alkaloids (RTA) and sinapine thiocyanate for protection against a prothrombotic state (PTS) associated with the tumor necrosis factor-alpha (TNF-α)-induced inflammatory injury of vascular endothelial cells (VECs). A TNF-α-induced VEC inflammatory injury model was established, and cell morphology of VECs was evaluated using scanning electron microscopy. In addition, reverse transcription-quantitative polymerase chain reaction and western blot analysis were performed to examine the mRNA and protein expression of coagulation-related factors, including nuclear factor-κB (NF-κB), transforming growth factor-β1 (TGF-β1), tissue factor (TF), plasminogen activator inhibitor (PAI-1), protease-activation receptors (PAR-1) and protein kinase C (PKC-α) in VECs. Combined treatment with RTA and sinapine thiocyanate was demonstrated to reduce, to a varying extent, the mRNA and protein expression of NF-κB, TGF-β1, TF, PAR-1, PKC-α and PAI-1. Furthermore, combined treatment with RTA and sinapine thiocyanate was able to downregulate the expression of coagulation-related factors in injured VECs, thereby inhibiting the PTS induced by vascular endothelial injury. The underlying mechanism is partially associated with the TF-mediated activation of the thrombin-receptor signaling pathway that suppresses coagulation during inflammation and balances fibrinolysis in order to inhibit fibrin generation and deposition. PMID:28587383

Mechanism of the protective effects of the combined treatment with rhynchophylla total alkaloids and sinapine thiocyanate against a prothrombotic state caused by vascular endothelial cell inflammatory damage.

PubMed

Li, Yunlun; Zhang, Xinya; Yang, Wenqing; Li, Chao; Chu, Yanjun; Jiang, Haiqiang; Shen, Zhenzhen

2017-06-01

The aim of the present study was to investigate the effect and the underlying mechanism of the combined treatment of rhynchophylla total alkaloids (RTA) and sinapine thiocyanate for protection against a prothrombotic state (PTS) associated with the tumor necrosis factor-alpha (TNF-α)-induced inflammatory injury of vascular endothelial cells (VECs). A TNF-α-induced VEC inflammatory injury model was established, and cell morphology of VECs was evaluated using scanning electron microscopy. In addition, reverse transcription-quantitative polymerase chain reaction and western blot analysis were performed to examine the mRNA and protein expression of coagulation-related factors, including nuclear factor-κB (NF-κB), transforming growth factor-β1 (TGF-β1), tissue factor (TF), plasminogen activator inhibitor (PAI-1), protease-activation receptors (PAR-1) and protein kinase C (PKC-α) in VECs. Combined treatment with RTA and sinapine thiocyanate was demonstrated to reduce, to a varying extent, the mRNA and protein expression of NF-κB, TGF-β1, TF, PAR-1, PKC-α and PAI-1. Furthermore, combined treatment with RTA and sinapine thiocyanate was able to downregulate the expression of coagulation-related factors in injured VECs, thereby inhibiting the PTS induced by vascular endothelial injury. The underlying mechanism is partially associated with the TF-mediated activation of the thrombin-receptor signaling pathway that suppresses coagulation during inflammation and balances fibrinolysis in order to inhibit fibrin generation and deposition.

Membrane Signaling Induced by High Doses of Ionizing Radiation in the Endothelial Compartment. Relevance in Radiation Toxicity

PubMed Central

Corre, Isabelle; Guillonneau, Maëva; Paris, François

2013-01-01

Tumor areas can now be very precisely delimited thanks to technical progress in imaging and ballistics. This has also led to the development of novel radiotherapy protocols, delivering higher doses of ionizing radiation directly to cancer cells. Despite this, radiation toxicity in healthy tissue remains a major issue, particularly with dose-escalation in these new protocols. Acute and late tissue damage following irradiation have both been linked to the endothelium irrigating normal tissues. The molecular mechanisms involved in the endothelial response to high doses of radiation are associated with signaling from the plasma membrane, mainly via the acid sphingomyelinase/ceramide pathway. This review describes this signaling pathway and discusses the relevance of targeting endothelial signaling to protect healthy tissues from the deleterious effects of high doses of radiation. PMID:24252908

Endothelial necrosis at 1h post-burn predicts progression of tissue injury

PubMed Central

Hirth, Douglas; McClain, Steve A.; Singer, Adam J.; Clark, Richard A.F.

2013-01-01

Burn injury progression has not been well characterized at the cellular level. To define burn injury progression in terms of cell death, histopathologic spatiotemporal relationships of cellular necrosis and apoptosis were investigated in a validated porcine model of vertical burn injury progression. Cell necrosis was identified by High Mobility Group Box 1 protein and apoptosis by Caspase 3a staining of tissue samples taken 1h, 24h and 7 days post-burn. Level of endothelial cell necrosis at 1h was predictive of level of apoptosis at 24h (Pearson's r=0.87) and of level of tissue necrosis at 7 days (Pearson's r=0.87). Furthermore, endothelial cell necrosis was deeper than interstitial cell necrosis at 1h (p<0.001). Endothelial cell necrosis at 1h divided the zone of injury progression (Jackson's zone of stasis) into an upper subzone with necrotic endothelial cells and initially viable adnexal and interstitial cells at 1h that progressed to necrosis by 24h, and a lower zone with initially viable endothelial cells at 1h, but necrosis and apoptosis of all cell types by 24h. Importantly, this spatiotemporal series of events and rapid progression resembles myocardial infarction and stroke, and implicates mechanisms of these injuries, ischemia, ischemia reperfusion, and programmed cell death, in burn progression. PMID:23627744

Effect of ambient temperature on the proliferation of brown adipocyte progenitors and endothelial cells during postnatal BAT development in Syrian hamsters.

PubMed

Nagaya, Kazuki; Okamatsu-Ogura, Yuko; Nio-Kobayashi, Junko; Nakagiri, Shohei; Tsubota, Ayumi; Kimura, Kazuhiro

2018-04-02

In Syrian hamsters, brown adipose tissue (BAT) develops postnatally through the proliferation and differentiation of brown adipocyte progenitors. In the study reported here, we investigated how ambient temperature influenced BAT formation in neonatal hamsters. In both hamsters raised at 23 or 30 °C, the interscapular fat changed from white to brown coloration in an age-dependent manner and acquired the typical morphological features of BAT by day 16. However, the expression of uncoupling protein 1, a brown adipocyte marker, and of vascular endothelial growth factor α were lower in the group raised at 30 °C than in that raised at 23 °C. Immunofluorescent staining revealed that the proportion of Ki67-expressing progenitors and endothelial cells was lower in the 30 °C group than in the 23 °C group. These results indicate that warm ambient temperature suppresses the proliferation of brown adipocyte progenitors and endothelial cells and negatively affects the postnatal development of BAT in Syrian hamsters.

Involvement of Vascular Endothelial Growth Factor in Kaposi's Sarcoma Associated with Acquired Immunodeficiency Syndrome

PubMed Central

Sakurada, Shinsaku; Kato, Tetsuji; Mashiba, Kohichi; Mori, Shigeo

1996-01-01

To examine the role of vascular endothelial growth factor (VEGF) in the development of edema associated with Kaposi's sarcoma (KS) in acquired immunodeficiency syndrome (AIDS), we exploited animal model systems to detect the activity that induces vascular hyper‐permeability (VHP) using cultured AIDS‐KS spindle cells. Cultured AIDS‐KS spindle cells and conditioned medium (AIDS‐KS‐CM) that had been semi‐purified through a heparin affinity column were tested for the ability to induce VHP in animals. The AIDS‐KS spindle cells and AIDS‐KS‐CM induced VHP that was histamine‐independent. The VHP‐inducing activity was detected in the 0.5 M NaCl fraction from the heparin affinity column and was blocked by anti‐VEGF neutralizing antibody. In addition, the production of VEGF was demonstrated in fresh AIDS‐KS tissue as well as in cultured AIDS‐KS cells, while control cells were negative for VEGF production. From these observations, we concluded that AIDS‐KS cells produce a factor(s) that promotes VHP, and this factor could be VEGF. PMID:9045943

Regression of vessels in the tunica vasculosa lentis is initiated by coordinated endothelial apoptosis: a role for vascular endothelial growth factor as a survival factor for endothelium.

PubMed

Mitchell, C A; Risau, W; Drexler, H C

1998-11-01

The development of the embryonic lens is dependent on the formation and regression of the tunica vasculosa lentis (TVL), which is a transiently occurring capillary plexus that surrounds the posterior part of the lens. In this study, by using the terminal deoxy-nucleotidyl transferase mediated nick end-labelling technique (TUNEL), electron microscopy, radioactive end-labelling of DNA extracted from TVL, and the Comet assay, we show that widespread apoptosis of the endothelial cells that constitute the TVL is occurring already at embryonic day 17.5 (E17.5) of mouse development, much earlier than was reported previously (Jack [1972a] Am. J. Ophthalmol. 74:261-272; Lang [1997] Cell Death Diff. 4:12-20). In addition to apoptotic cell death, regression of this structure is associated with loss of capillary integrity, leakage of erythrocytes into the vitreal compartment, and phagocytosis of the apoptotic endothelium by tissue macrophages (hyalocytes). In situ hybridization experiments with probes for the flk-1 receptor and its high-affinity ligand, vascular endothelial growth factor (VEGF; Terman et al. [1992] Biochem. Biophys. Res. Commun. 187:1579-1586; Millauer et al. [1993] Cell 72:835-846), revealed strong endothelial cell expression for flk-1 in the eyes of E13.5-E17.5 embryos. VEGF mRNA was detected in lens epithelial cells located at the posterior pole of the developing lens in E13.5 embryos, in close proximity to the TVL capillaries. At later times (E14.5-E17.5), when the lens epithelial cells have differentiated into primary lens fiber cells, and a thick lenticular capsule is formed, the expression of VEGF mRNA becomes restricted to the anterior and equatorial portions of the lens. The physical separation of the VEGF-producing cells from the flk-1-expressing endothelium (due to the differentiation of the lens epithelial cells into lens fiber cells and the formation of the lenticular capsule) may deprive the endothelium of an essential survival factor and, thus, may constitute the primary mechanism that is responsible for the induction of endothelial cell apoptosis in this model.

Vascular Injury Triggers Krüppel-Like Factor 6 (KLF6) Mobilization and Cooperation with Sp1 to Promote Endothelial Activation through Upregulation of the Activin Receptor-Like Kinase 1 (ALK1) Gene

PubMed Central

Garrido-Martín, Eva M.; Blanco, Francisco J.; Roquè, Mercé; Novensà, Laura; Tarocchi, Mirko; Lee, Ursula E.; Suzuki, Toru; Friedman, Scott L.; Botella, Luisa M.; Bernabéu, Carmelo

2012-01-01

Rationale Activin receptor-Like Kinase-1 (ALK1) is an endothelial TGF-β receptor involved in angiogenesis. ALK1 expression is high in the embryo vasculature, becoming less detectable in the quiescent endothelium of adult stages. However, ALK1 expression becomes rapidly increased after angiogenic stimuli such as vascular injury. Objective To characterize the molecular mechanisms underlying the regulation of ALK1 upon vascular injury. Methods and Results Alk1 becomes strongly upregulated in endothelial (EC) and vascular smooth muscle cells (vSMC) of mouse femoral arteries after wire-induced endothelial denudation. In vitro, denudation of monolayers of Human Umbilical Vein Endothelial Cells (HUVEC) also leads to an increase in ALK1. Interestingly, a key factor in tissue remodeling, Krüppel-like factor 6 (KLF6), translocates to the cell nucleus during wound healing, concomitantly with an increase in the ALK1 gene transcriptional rate. KLF6 knock down in HUVECs promotes ALK1 mRNA downregulation. Moreover, Klf6+/− mice have lower levels of Alk1 in their vasculature compared with their wild type siblings. Chromatin immunoprecipitation assays show that KLF6 interacts with ALK1 promoter in ECs, and this interaction is enhanced during wound healing. We demonstrate that KLF6 is transactivating ALK1 gene, and this transactivation occurs by a synergistic cooperative mechanism with Sp1. Finally, Alk1 levels in vSMCs are not directly upregulated in response to damage, but in response to soluble factors, such as IL-6, released from ECs after injury. Conclusions ALK1 is upregulated in ECs during vascular injury by a synergistic cooperative mechanism between KLF6 and Sp1, and in vSMCs by an EC-vSMC paracrine communication during vascular remodeling. PMID:23048070

A modified collagen gel enhances healing outcome in a preclinical swine model of excisional wounds.

PubMed

Elgharably, Haytham; Roy, Sashwati; Khanna, Savita; Abas, Motaz; Dasghatak, Piya; Das, Amitava; Mohammed, Kareem; Sen, Chandan K

2013-01-01

Collagen-based dressings are of great interest in wound care. However, evidence supporting their mechanism of action is scanty. This work provides first results from a preclinical swine model of excisional wounds, elucidating the mechanism of action of a modified collagen gel (MCG) dressing. Following wounding, wound-edge tissue was collected at specific time intervals (3, 7, 14, and 21 days postwounding). On day 7, histological analysis showed significant increase in the length of rete ridges, suggesting improved biomechanical properties of the healing wound tissue. Rapid and transient mounting of inflammation is necessary for efficient healing. MCG significantly accelerated neutrophil and macrophage recruitment to the wound site on day 3 and day 7 with successful resolution of inflammation on day 21. MCG induced monocyte chemotactic protein-1 expression in neutrophil-like human promyelocytic leukemia-60 cells in vitro. In vivo, MCG-treated wound tissue displayed elevated vascular endothelial growth factor expression. Consistently, MCG-treated wounds displayed significantly higher abundance of endothelial cells with increased blood flow to the wound area indicating improved vascularization. This observation was explained by the finding that MCG enhanced proliferation of wound-site endothelial cells. In MCG-treated wound tissue, Masson's trichrome and picrosirius red staining showed higher abundance of collagen and increased collagen type I:III ratio. This work presents first evidence from a preclinical setting explaining how a collagen-based dressing may improve wound closure by targeting multiple key mechanisms. The current findings warrant additional studies to determine whether the responses to the MCG are different from other collagen-based products used in clinical setting. © 2013 by the Wound Healing Society.

Vascular Gene Expression in Nonneoplastic and Malignant Brain

PubMed Central

Madden, Stephen L.; Cook, Brian P.; Nacht, Mariana; Weber, William D.; Callahan, Michelle R.; Jiang, Yide; Dufault, Michael R.; Zhang, Xiaoming; Zhang, Wen; Walter-Yohrling, Jennifer; Rouleau, Cecile; Akmaev, Viatcheslav R.; Wang, Clarence J.; Cao, Xiaohong; St. Martin, Thia B.; Roberts, Bruce L.; Teicher, Beverly A.; Klinger, Katherine W.; Stan, Radu-Virgil; Lucey, Brenden; Carson-Walter, Eleanor B.; Laterra, John; Walter, Kevin A.

2004-01-01

Malignant gliomas are uniformly lethal tumors whose morbidity is mediated in large part by the angiogenic response of the brain to the invading tumor. This profound angiogenic response leads to aggressive tumor invasion and destruction of surrounding brain tissue as well as blood-brain barrier breakdown and life-threatening cerebral edema. To investigate the molecular mechanisms governing the proliferation of abnormal microvasculature in malignant brain tumor patients, we have undertaken a cell-specific transcriptome analysis from surgically harvested nonneoplastic and tumor-associated endothelial cells. SAGE-derived endothelial cell gene expression patterns from glioma and nonneoplastic brain tissue reveal distinct gene expression patterns and consistent up-regulation of certain glioma endothelial marker genes across patient samples. We define the G-protein-coupled receptor RDC1 as a tumor endothelial marker whose expression is distinctly induced in tumor endothelial cells of both brain and peripheral vasculature. Further, we demonstrate that the glioma-induced gene, PV1, shows expression both restricted to endothelial cells and coincident with endothelial cell tube formation. As PV1 provides a framework for endothelial cell caveolar diaphragms, this protein may serve to enhance glioma-induced disruption of the blood-brain barrier and transendothelial exchange. Additional characterization of this extensive brain endothelial cell gene expression database will provide unique molecular insights into vascular gene expression. PMID:15277233

High Dietary Fructose: Direct or Indirect Dangerous Factors Disturbing Tissue and Organ Functions.

PubMed

Zhang, Dong-Mei; Jiao, Rui-Qing; Kong, Ling-Dong

2017-03-29

High dietary fructose is a major contributor to insulin resistance and metabolic syndrome, disturbing tissue and organ functions. Fructose is mainly absorbed into systemic circulation by glucose transporter 2 (GLUT2) and GLUT5, and metabolized in liver to produce glucose, lactate, triglyceride (TG), free fatty acid (FFA), uric acid (UA) and methylglyoxal (MG). Its extrahepatic absorption and metabolism also take place. High levels of these metabolites are the direct dangerous factors. During fructose metabolism, ATP depletion occurs and induces oxidative stress and inflammatory response, disturbing functions of local tissues and organs to overproduce inflammatory cytokine, adiponectin, leptin and endotoxin, which act as indirect dangerous factors. Fructose and its metabolites directly and/or indirectly cause oxidative stress, chronic inflammation, endothelial dysfunction, autophagy and increased intestinal permeability, and then further aggravate the metabolic syndrome with tissue and organ dysfunctions. Therefore, this review addresses fructose-induced metabolic syndrome, and the disturbance effects of direct and/or indirect dangerous factors on the functions of liver, adipose, pancreas islet, skeletal muscle, kidney, heart, brain and small intestine. It is important to find the potential correlations between direct and/or indirect risk factors and healthy problems under excess dietary fructose consumption.

High Dietary Fructose: Direct or Indirect Dangerous Factors Disturbing Tissue and Organ Functions

PubMed Central

Zhang, Dong-Mei; Jiao, Rui-Qing; Kong, Ling-Dong

2017-01-01

High dietary fructose is a major contributor to insulin resistance and metabolic syndrome, disturbing tissue and organ functions. Fructose is mainly absorbed into systemic circulation by glucose transporter 2 (GLUT2) and GLUT5, and metabolized in liver to produce glucose, lactate, triglyceride (TG), free fatty acid (FFA), uric acid (UA) and methylglyoxal (MG). Its extrahepatic absorption and metabolism also take place. High levels of these metabolites are the direct dangerous factors. During fructose metabolism, ATP depletion occurs and induces oxidative stress and inflammatory response, disturbing functions of local tissues and organs to overproduce inflammatory cytokine, adiponectin, leptin and endotoxin, which act as indirect dangerous factors. Fructose and its metabolites directly and/or indirectly cause oxidative stress, chronic inflammation, endothelial dysfunction, autophagy and increased intestinal permeability, and then further aggravate the metabolic syndrome with tissue and organ dysfunctions. Therefore, this review addresses fructose-induced metabolic syndrome, and the disturbance effects of direct and/or indirect dangerous factors on the functions of liver, adipose, pancreas islet, skeletal muscle, kidney, heart, brain and small intestine. It is important to find the potential correlations between direct and/or indirect risk factors and healthy problems under excess dietary fructose consumption. PMID:28353649

[(Pro) renin receptor in the pathogenesis of proliferative diabetic retinopathy].

PubMed

Kanda, Atsuhiro

2014-11-01

The renin-angiotensin system (RAS), originally regarded as an important controller of systemic blood pressure (circulatory RAS), plays a pivotal role in pathological vascular conditions including inflammation and angiogenesis (tissue RAS). (Pro) renin receptor [(P) RR] is known to bind with prorenin causing the dual activation of tissue renin-angiotensin system (RAS) together with RAS-independent intracellular signaling pathways and contributes to the molecular pathogenesis of end-organ damage. In this review, we investigated localization and expression of (P)RR in fibrovascular tissues and vitreous fluids from patients with proliferative diabetic retinopathy and evaluated the molecular mechanisms in vitro in order to confirm the conclusions regarding (P) RR from animal studies. (P)RR immunoreactivity was detected in vascular endothelial cells, co-localized with prorenin, phosphorylated extracellular signal-regulated kinase and vascular endothelial growth factor (VEGF). Protein levels of soluble (P) RR in the vitreous fluids were higher in proliferative diabetic retinopathy (PDR) eyes than in non-diabetic control eyes, and were significantly correlated with vitreous VEGF levels and the vascular density of fibrovascular tissues. We herein report the first evidence that shows the close association of (P) RR with angiogenic activity in human PDR. The present data suggest the validity of (P) RR as a molecular target for the treatment of PDR.

Bioprinted Osteogenic and Vasculogenic Patterns for Engineering 3D Bone Tissue.

PubMed

Byambaa, Batzaya; Annabi, Nasim; Yue, Kan; Trujillo-de Santiago, Grissel; Alvarez, Mario Moisés; Jia, Weitao; Kazemzadeh-Narbat, Mehdi; Shin, Su Ryon; Tamayol, Ali; Khademhosseini, Ali

2017-08-01

Fabricating 3D large-scale bone tissue constructs with functional vasculature has been a particular challenge in engineering tissues suitable for repairing large bone defects. To address this challenge, an extrusion-based direct-writing bioprinting strategy is utilized to fabricate microstructured bone-like tissue constructs containing a perfusable vascular lumen. The bioprinted constructs are used as biomimetic in vitro matrices to co-culture human umbilical vein endothelial cells and bone marrow derived human mesenchymal stem cells in a naturally derived hydrogel. To form the perfusable blood vessel inside the bioprinted construct, a central cylinder with 5% gelatin methacryloyl (GelMA) hydrogel at low methacryloyl substitution (GelMA LOW ) was printed. We also develop cell-laden cylinder elements made of GelMA hydrogel loaded with silicate nanoplatelets to induce osteogenesis, and synthesized hydrogel formulations with chemically conjugated vascular endothelial growth factor to promote vascular spreading. It was found that the engineered construct is able to support cell survival and proliferation during maturation in vitro. Additionally, the whole construct demonstrates high structural stability during the in vitro culture for 21 days. This method enables the local control of physical and chemical microniches and the establishment of gradients in the bioprinted constructs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chronic social isolation in the prairie vole induces endothelial dysfunction: implications for depression and cardiovascular disease

PubMed Central

Peuler, Jacob D.; Scotti, Melissa-Ann L.; Phelps, Laura E.; McNeal, Neal; Grippo, Angela J.

2012-01-01

Humans with depression show impaired endothelium-dependent vasodilation, one recent demonstration of which was in the form of a reduced acetylcholine (ACh)-induced relaxation of adrenergically-precontracted small arteries biopsied from older depressed patients. Results from such uses of ACh in general have been validated as the most predictive marker of endothelium-related cardiovascular diseases. Accordingly, we examined vascular reactivity to ACh in the socially isolated prairie vole, a new animal model relevant to human depression and cardiovascular disease. Thoracic aortas were carefully dissected from female prairie voles after one month of social isolation (versus pairing with a sibling). Only aortas that contracted to the adrenergic agent phenylephrine (PE) and then relaxed to ACh were evaluated. Among those, ACh-induced relaxations were significantly reduced by social isolation (p<0.05), with maximum relaxation reaching only 30% (of PE-induced precontraction) compared to 47% in aortas from paired (control) animals. Experimental removal of the endothelium from an additional set of aortic tissues abolished all ACh relaxations including that difference. In these same tissues, maximally-effective concentrations of the nitric oxide-donor nitroprusside still completely relaxed all PE-induced precontraction of the endothelial-free smooth muscle, and to the same degree in tissues from isolated versus paired animals. Finally, in the absence of PE-induced precontraction ACh did not relax but rather contracted aortic tissues, and to a significantly greater extent in tissues from socially isolated animals if the endothelium was intact (p<0.05). Thus, social isolation in the prairie vole may 1) impair normal release of protective anti-atherosclerotic factors like nitric oxide from the vascular endothelium (without altering the inherent responsiveness of the vascular smooth muscle to such factors) and 2) cause the endothelium to release contracting factors. To our knowledge this is the first demonstration of this phenomenon in an animal model of depression induced solely by social isolation. These findings have implications for understanding mechanisms involved in depression and cardiovascular disease. PMID:22469565

Alternagin-C (ALT-C), a Disintegrin-Like Cys-Rich Protein Isolated from the Venom of the Snake Rhinocerophis alternatus, Stimulates Angiogenesis and Antioxidant Defenses in the Liver of Freshwater Fish, Hoplias malabaricus

PubMed Central

Monteiro, Diana Amaral; Selistre-de-Araújo, Heloisa Sobreiro; Tavares, Driele; Kalinin, Ana Lúcia; Rantin, Francisco Tadeu

2017-01-01

Alternagin-C (ALT-C) is a disintegrin-like protein isolated from Rhinocerophis alternatus snake venom, which induces endothelial cell proliferation and angiogenesis. The aim of this study was to evaluate the systemic effects of a single dose of alternagin-C (0.5 mg·kg−1, via intra-arterial) on oxidative stress biomarkers, histological alterations, vascular endothelial growth factor (VEGF) production, and the degree of vascularization in the liver of the freshwater fish traíra, Hoplias malabaricus, seven days after the initiation of therapy. ALT-C treatment increased VEGF levels and hepatic angiogenesis. ALT-C also enhanced hepatic antioxidant enzymes activities such as superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase, decreasing the basal oxidative damage to lipids and proteins in the fish liver. These results indicate that ALT-C improved hepatic tissue and may play a crucial role in tissue regeneration mechanisms. PMID:28956818

A modified collagen gel dressing promotes angiogenesis in a preclinical swine model of chronic ischemic wounds.

PubMed

Elgharably, Haytham; Ganesh, Kasturi; Dickerson, Jennifer; Khanna, Savita; Abas, Motaz; Ghatak, Piya Das; Dixit, Sriteja; Bergdall, Valerie; Roy, Sashwati; Sen, Chandan K

2014-01-01

We recently performed proteomic characterization of a modified collagen gel (MCG) dressing and reported promising effects of the gel in healing full-thickness excisional wounds. In this work, we test the translational relevance of our aforesaid findings by testing the dressing in a swine model of chronic ischemic wounds recently reported by our laboratory. Full-thickness excisional wounds were established in the center of bipedicle ischemic skin flaps on the backs of animals. Ischemia was verified by laser Doppler imaging, and MCG was applied to the test group of wounds. Seven days post wounding, macrophage recruitment to the wound was significantly higher in MCG-treated ischemic wounds. In vitro, MCG up-regulated expression of Mrc-1 (a reparative M2 macrophage marker) and induced the expression of anti-inflammatory cytokine interleukin (IL)-10 and of fibroblast growth factor-basic (β-FGF). An increased expression of CCR2, an M2 macrophage marker, was noted in the macrophages from MCG treated wounds. Furthermore, analyses of wound tissues 7 days post wounding showed up-regulation of transforming growth factor-β, vascular endothelial growth factor, von Willebrand's factor, and collagen type I expression in MCG-treated ischemic wounds. At 21 days post wounding, MCG-treated ischemic wounds displayed higher abundance of proliferating endothelial cells that formed mature vascular structures and increased blood flow to the wound. Fibroblast count was markedly higher in MCG-treated ischemic wound-edge tissue. In addition, MCG-treated wound-edge tissues displayed higher abundance of mature collagen with increased collagen type I : III deposition. Taken together, MCG helped mount a more robust inflammatory response that resolved in a timely manner, followed by an enhanced proliferative phase, angiogenic outcome, and postwound tissue remodeling. Findings of the current study warrant clinical testing of MCG in a setting of ischemic chronic wounds. © 2014 by the Wound Healing Society.

Avian leukosis virus subgroup J induces VEGF expression via NF-κB/PI3K-dependent IL-6 production.

PubMed

Gao, Yanni; Zhang, Yao; Yao, Yongxiu; Guan, Xiaolu; Liu, Yongzhen; Qi, Xiaole; Wang, Yongqiang; Liu, Changjun; Zhang, Yanping; Gao, Honglei; Nair, Venugopal; Wang, Xiaomei; Gao, Yulong

2016-12-06

Avian leukosis virus subgroup J (ALV-J) is an oncogenic virus causing hemangiomas and myeloid tumors in chickens. Interleukin-6 (IL-6) is a multifunctional pro-inflammatory interleukin involved in many types of cancer. We previously demonstrated that IL-6 expression was induced following ALV-J infection in chickens. The aim of this study is to characterize the mechanism by which ALV-J induces IL-6 expression, and the role of IL-6 in tumor development. Our results demonstrate that ALV-J infection increases IL-6 expression in chicken splenocytes, peripheral blood lymphocytes, and vascular endothelial cells. IL-6 production is induced by the ALV-J envelope protein gp85 and capsid protein p27 via PI3K- and NF-κB-mediated signaling. IL-6 in turn induced expression of vascular endothelial growth factor (VEGF)-A and its receptor, VEGFR-2, in vascular endothelial cells and embryonic vascular tissues. Suppression of IL-6 using siRNA inhibited the ALV-J induced VEGF-A and VEGFR-2 expression in vascular endothelial cells, indicating that the ALV-J-induced VEGF-A/VEGFR-2 expression is mediated by IL-6. As VEGF-A and VEGFR-2 are important factors in oncogenesis, our findings suggest that ALV-J hijacks IL-6 to promote tumorigenesis, and indicate that IL-6 could potentially serve as a therapeutic target in ALV-J infections.

A biological approach to assembling tissue modules through endothelial capillary network formation.

PubMed

Riesberg, Jeremiah J; Shen, Wei

2015-09-01

To create functional tissues having complex structures, bottom-up approaches to assembling small tissue modules into larger constructs have been emerging. Most of these approaches are based on chemical reactions or physical interactions at the interface between tissue modules. Here we report a biological assembly approach to integrate small tissue modules through endothelial capillary network formation. When adjacent tissue modules contain appropriate extracellular matrix materials and cell types that support robust endothelial capillary network formation, capillary tubules form and grow across the interface, resulting in assembly of the modules into a single, larger construct. It was shown that capillary networks formed in modules of dense fibrin gels seeded with human umbilical vein endothelial cells (HUVECs) and mesenchymal stem cells (MSCs); adjacent modules were firmly assembled into an integrated construct having a strain to failure of 117 ± 26%, a tensile strength of 2208 ± 83 Pa and a Young's modulus of 2548 ± 574 Pa. Under the same culture conditions, capillary networks were absent in modules of dense fibrin gels seeded with either HUVECs or MSCs alone; adjacent modules disconnected even when handled gently. This biological assembly approach eliminates the need for chemical reactions or physical interactions and their associated limitations. In addition, the integrated constructs are prevascularized, and therefore this bottom-up assembly approach may also help address the issue of vascularization, another key challenge in tissue engineering. Copyright © 2015 John Wiley & Sons, Ltd.

Targeting NCK-Mediated Endothelial Cell Front-Rear Polarity Inhibits Neo-Vascularization

PubMed Central

Dubrac, Alexandre; Genet, Gael; Ola, Roxana; Zhang, Feng; Pibouin-Fragner, Laurence; Han, Jinah; Zhang, Jiasheng; Thomas, Jean-Léon; Chedotal, Alain; Schwartz, Martin A.; Eichmann, Anne

2015-01-01

Background Sprouting angiogenesis is a key process driving blood vessel growth in ischemic tissues and an important drug target in a number of diseases, including wet macular degeneration and wound healing. Endothelial cells forming the sprout must develop front-rear polarity to allow sprout extension. The adaptor proteins Nck1 and 2 are known regulators of cytoskeletal dynamics and polarity, but their function in angiogenesis is poorly understood. Here we show that the Nck adaptors are required for endothelial cell front-rear polarity and migration downstream of the angiogenic growth factors VEGF-A and Slit2. Methods and Results Mice carrying inducible, endothelial-specific Nck1/2 deletions fail to develop front-rear polarized vessel sprouts and exhibit severe angiogenesis defects in the postnatal retina and during embryonic development. Inactivation of NCK1 and 2 inhibits polarity by preventing Cdc42 and Pak2 activation by VEGF-A and Slit2. Mechanistically, NCK binding to ROBO1 is required for both Slit2 and VEGF induced front-rear polarity. Selective inhibition of polarized endothelial cell migration by targeting Nck1/2 prevents hypersprouting induced by Notch or Bmp signaling inhibition, as well as pathological ocular neovascularization and wound healing. Conclusions These data reveal a novel signal integration mechanism involving NCK1/2, ROBO1/2 and VEGFR2 that controls endothelial cell front-rear polarity during sprouting angiogenesis. PMID:26659946

Targeting NCK-Mediated Endothelial Cell Front-Rear Polarity Inhibits Neovascularization.

PubMed

Dubrac, Alexandre; Genet, Gael; Ola, Roxana; Zhang, Feng; Pibouin-Fragner, Laurence; Han, Jinah; Zhang, Jiasheng; Thomas, Jean-Léon; Chedotal, Alain; Schwartz, Martin A; Eichmann, Anne

2016-01-26

Sprouting angiogenesis is a key process driving blood vessel growth in ischemic tissues and an important drug target in a number of diseases, including wet macular degeneration and wound healing. Endothelial cells forming the sprout must develop front-rear polarity to allow sprout extension. The adaptor proteins Nck1 and 2 are known regulators of cytoskeletal dynamics and polarity, but their function in angiogenesis is poorly understood. Here, we show that the Nck adaptors are required for endothelial cell front-rear polarity and migration downstream of the angiogenic growth factors VEGF-A and Slit2. Mice carrying inducible, endothelial-specific Nck1/2 deletions fail to develop front-rear polarized vessel sprouts and exhibit severe angiogenesis defects in the postnatal retina and during embryonic development. Inactivation of NCK1 and 2 inhibits polarity by preventing Cdc42 and Pak2 activation by VEGF-A and Slit2. Mechanistically, NCK binding to ROBO1 is required for both Slit2- and VEGF-induced front-rear polarity. Selective inhibition of polarized endothelial cell migration by targeting Nck1/2 prevents hypersprouting induced by Notch or Bmp signaling inhibition, and pathological ocular neovascularization and wound healing, as well. These data reveal a novel signal integration mechanism involving NCK1/2, ROBO1/2, and VEGFR2 that controls endothelial cell front-rear polarity during sprouting angiogenesis. © 2015 American Heart Association, Inc.

The p38 pathway, a major pleiotropic cascade that transduces stress and metastatic signals in endothelial cells

PubMed Central

Corre, Isabelle; Paris, François; Huot, Jacques

2017-01-01

By gating the traffic of molecules and cells across the vessel wall, endothelial cells play a central role in regulating cardiovascular functions and systemic homeostasis and in modulating pathophysiological processes such as inflammation and immunity. Accordingly, the loss of endothelial cell integrity is associated with pathological disorders that include atherosclerosis and cancer. The p38 mitogen-activated protein kinase (MAPK) cascades are major signaling pathways that regulate several functions of endothelial cells in response to exogenous and endogenous stimuli including growth factors, stress and cytokines. The p38 MAPK family contains four isoforms p38α, p38β, p38γ and p38δ that are encoded by four different genes. They are all widely expressed although to different levels in almost all human tissues. p38α/MAPK14, that is ubiquitously expressed is the prototype member of the family and is referred here as p38. It regulates the production of inflammatory mediators, and controls cell proliferation, differentiation, migration and survival. Its activation in endothelial cells leads to actin remodeling, angiogenesis, DNA damage response and thereby has major impact on cardiovascular homeostasis, and on cancer progression. In this manuscript, we review the biology of p38 in regulating endothelial functions especially in response to oxidative stress and during the metastatic process. PMID:28903453

IL-11 facilitates a novel connection between RA joint fibroblasts and endothelial cells.

PubMed

Elshabrawy, Hatem A; Volin, Michael V; Essani, Abdul B; Chen, Zhenlong; McInnes, Iain B; Van Raemdonck, Katrien; Palasiewicz, Karol; Arami, Shiva; Gonzalez, Mark; Ashour, Hossam M; Kim, Seung-Jae; Zhou, Guofei; Fox, David A; Shahrara, Shiva

2018-05-01

IL-11 has been detected in inflamed joints; however, its role in the pathogenesis of arthritis is not yet clear. Studies were conducted to characterize the expression and functional significance of IL-11 and IL-11Rα in rheumatoid arthritis (RA). IL-11 levels were elevated in RA synovial fluid (SF) compared to osteoarthritis (OA) SF and plasma from RA, OA and normal individuals (NLs). Morphologic studies established that IL-11 was detected in lining fibroblasts and macrophages in addition to sublining endothelial cells and macrophages at higher levels in RA compared to NL synovial tissues. Since IL-11Rα was exclusively expressed in RA fibroblasts and endothelial cells, macrophages were not involved in IL-11 effector function. Ligation of IL-11 to IL-11Rα strongly provoked fibroblast infiltration into RA joint, while cell proliferation was unaffected by this process. Secretion of IL-8 and VEGF from IL-11 activated RA fibroblasts was responsible for the indirect effect of IL-11 on endothelial cell transmigration and tube formation. Moreover, IL-11 blockade impaired RA SF capacity to elicit endothelial cell transmigration and tube formation. We conclude that IL-11 binding to endothelial IL-11Rα can directly induce RA angiogenesis. In addition, secretion of proangiogenic factors from migrating fibroblasts potentiated by IL-11 can indirectly contribute to RA neovascularization.

Sarcoidosis with high serum levels of vascular endothelial growth factor (VEGF), showing RS3PE-like symptoms in extremities.

PubMed

Matsuda, Masayuki; Sakurai, Kumi; Fushimi, Tomohisa; Yamamoto, Kanji; Rokuhara, Shiho; Hosaka, Naritoshi; Ikeda, Shu-ichi

2004-06-01

We report a patient with sarcoidosis who showed edema in the distal portion of all extremities, particularly the legs, as seen in remitting seronegative symmetrical synovitis with pitting edema (RS3PE). Magnetic resonance imaging demonstrated diffuse abnormal intensity in subcutaneous tissues of both legs, and skin biopsy led to a diagnosis of sarcoidosis. Vascular endothelial growth factor (VEGF) showed a high serum level, which decreased soon after starting oral prednisolone, in parallel with an improvement in the limb edema. In this patient VEGF as well as infiltration by sarcoid granuloma in the skin might have played an important role in the pathogenesis of RS3PE-like symptoms in the extremities. When painful pitting edema is seen predominantly in the distal portion of all extremities, sarcoidosis as well as RS3PE should be considered as a possible diagnosis.

Generation of a felinized swine endothelial cell line by expression of feline decay-accelerating factor.

PubMed

Izuhara, Luna; Tatsumi, Norifumi; Miyagawa, Shuji; Iwai, Satomi; Watanabe, Masahito; Yamanaka, Shuichiro; Katsuoka, Yuichi; Nagashima, Hiroshi; Okano, Hirotaka J; Yokoo, Takashi

2015-01-01

Embryonic stem cell research has facilitated the generation of many cell types for the production of tissues and organs for both humans and companion animals. Because ≥30% of pet cats suffer from chronic kidney disease (CKD), xenotransplantation between pigs and cats has been studied. For a successful pig to cat xenotransplant, the immune reaction must be overcome, especially hyperacute rejection. In this study, we isolated the gene for feline decay-accelerating factor (fDAF), an inhibitor of complement proteins, and transfected a swine endothelial cell line with fDAF to "felinize" the pig cells. These fDAF-expressing cells were resistant to feline serum containing anti-pig antibodies, suggesting that felinized pig cells were resistant to hyperacute rejection. Our results suggest that a "felinized" pig kidney can be generated for the treatment of CKD in cats in the future.

p38 Signaling and Receptor Recycling Events in a Microfluidic Endothelial Cell Adhesion Assay

PubMed Central

Vickers, Dwayne A. L.; Chory, Emma J.; Harless, Megan C.; Murthy, Shashi K.

2013-01-01

Adhesion-based microfluidic cell separation has proven to be very useful in applications ranging from cancer diagnostics to tissue engineering. This process involves functionalizing microchannel surfaces with a capture molecule. High specificity and purity capture can be achieved using this method. Despite these advances, little is known about the mechanisms that govern cell capture within these devices and their relationships to basic process parameters such as fluid shear stress and the presence of soluble factors. This work examines how the adhesion of human endothelial cells (ECs) is influenced by a soluble tetrapeptide, Arg-Glu-Asp-Val (REDV) and fluidic shear stress. The ability of these ECs to bind within microchannels coated with REDV is shown to be governed by shear- and soluble-factor mediated changes in p38 mitogen-activated protein kinase expression together with recycling of adhesion receptors from the endosome. PMID:23762436

Systemic sclerosis and infections.

PubMed

Randone, Silvia Bellando; Guiducci, Serena; Cerinic, Marco Matucci

2008-10-01

Systemic sclerosis (SSc) is an autoimmune disease characterized by vascular obliteration, excessive extracellular matrix deposition and fibrosis of the connective tissues of the skin, lungs, gastrointestinal tract, heart, and kidneys. Numerous infectious agents (bacterial and viral) have been proposed as possible triggering factors (Parvovirus B19, Cytomegalovirus, Epstein-Barr virus, Retroviruses). Homology between viruses and autoantibody targets suggests that molecular mimicry may have a role in initiating antibody response in different disorders characterized by diffuse vascular disease, including SSc. Endothelial cell may be infected bacteria or viruses that play a particular role in inducing vasculitis. The pathogenic hypothesis include: a mechanism of molecular mimicry, the role played by endothelial cell damage, the presence of superantigens and the role of microchimeric cells. Although several studies provide important information linking infectious agents to SSc, a direct casual association between infections and SSc is still missing. In SSc viral products could synergize with other factors in the microenvironment predisposing to SSc development.

Blocking NF-κB: an inflammatory issue.

PubMed

Rahman, Arshad; Fazal, Fabeha

2011-11-01

The nuclear factor (NF)-κB is considered the master regulator of inflammatory responses. Studies in mouse models have established this transcription factor as an important mediator of many inflammatory disease states, including pulmonary diseases such as acute lung injury and acute respiratory distress syndrome. Endothelial cells provide the first barrier for leukocytes migrating to the inflamed sites and hence offer an attractive cellular context for targeting NF-κB for treatment of these diseases. However, recent studies showing that NF-κB also plays an important role in resolution phase of inflammation and in tissue repair and homeostasis have challenged the view of therapeutic inhibition of NF-κB. This article reviews the regulation of NF-κB in the context of endothelial cell signaling and provides a perspective on why "dampening" rather than "abolishing" NF-κB activation may be a safe and effective treatment strategy for inflammation-associated pulmonary and other inflammatory diseases.

Endothelial-derived interleukin-6 induces cancer stem cell motility by generating a chemotactic gradient towards blood vessels.

PubMed

Kim, Hong Sun; Chen, Yu-Chih; Nör, Felipe; Warner, Kristy A; Andrews, April; Wagner, Vivian P; Zhang, Zhaocheng; Zhang, Zhixiong; Martins, Manoela D; Pearson, Alexander T; Yoon, Euisik; Nör, Jacques E

2017-11-21

Recent evidence suggests that the metastatic spread of head and neck squamous cell carcinomas (HNSCC) requires the function of cancer stem cells endowed with multipotency, self-renewal, and high tumorigenic potential. We demonstrated that cancer stem cells reside in perivascular niches and are characterized by high aldehyde dehydrogenase (ALDH) activity and high CD44 expression (ALDH high CD44 high ) in HNSCC. Here, we hypothesize that endothelial cell-secreted interleukin-6 (IL-6) contributes to tumor progression by enhancing the migratory phenotype and survival of cancer stem cells. Analysis of tissue microarrays generated from the invasive fronts of 77 HNSCC patients followed-up for up to 11 years revealed that high expression of IL-6 receptor (IL-6R) (p=0.0217) or co-receptor gp130 (p=0.0422) correlates with low HNSCC patient survival. We observed that endothelial cell-secreted factors induce epithelial to mesenchymal transition (EMT) and enhance invasive capacity of HNSCC cancer stem cells. Conditioned medium from CRISPR/Cas9-mediated IL-6 knockout primary human endothelial cells is less chemotactic for cancer stem cells in a microfluidics-based system than medium from control endothelial cells (p<0.05). Blockade of the IL-6 pathway with a humanized anti-IL-6R antibody (tocilizumab) inhibited endothelial cell-induced motility in vitro and decreased the fraction of cancer stem cells in vivo . Notably, xenograft HNSCC tumors vascularized with IL-6-knockout endothelial cells exhibited slower tumor growth and smaller cancer stem cell fraction. These findings demonstrate that endothelial cell-secreted IL-6 enhances the motility and survival of highly tumorigenic cancer stem cells, suggesting that endothelial cells can create a chemotactic gradient that enables the movement of carcinoma cells towards blood vessels.

Co-immobilization of adhesive peptides and VEGF within a dextran-based coating for vascular applications.

PubMed

Noel, Samantha; Fortier, Charles; Murschel, Frederic; Belzil, Antoine; Gaudet, Guillaume; Jolicoeur, Mario; De Crescenzo, Gregory

2016-06-01

Multifunctional constructs providing a proper environment for adhesion and growth of selected cell types are needed for most tissue engineering and regenerative medicine applications. In this context, vinylsulfone (VS)-modified dextran was proposed as a matrix featuring low-fouling properties as well as multiple versatile moieties. The displayed VS groups could indeed react with thiol, amine or hydroxyl groups, be it for surface grafting, crosslinking or subsequent tethering of biomolecules. In the present study, a library of dextran-VS was produced, grafted to aminated substrates and characterized in terms of degree of VS modification (%VS), cell-repelling properties and potential for the oriented grafting of cysteine-tagged peptides. As a bioactive coating of vascular implants, ECM peptides (e.g. RGD) as well as vascular endothelial growth factor (VEGF) were co-immobilized on one of the most suitable dextran-VS coating (%VS=ca. 50% of saccharides units). Both RGD and VEGF were efficiently tethered at high densities (ca. 1nmol/cm(2) and 50fmol/cm(2), respectively), and were able to promote endothelial cell adhesion as well as proliferation. The latter was enhanced to the same extent as with soluble VEGF and proved selective to endothelial cells over smooth muscle cells. Altogether, multiple biomolecules could be efficiently incorporated into a dextran-VS construct, while maintaining their respective biological activity. This work addresses the need for multifunctional coatings and selective cell response inherent to many tissue engineering and regenerative medicine applications, for instance, vascular graft. More specifically, a library of dextrans was first generated through vinylsulfone (VS) modification. Thoroughly selected dextran-VS provided an ideal platform for unbiased study of cell response to covalently grafted biomolecules. Considering that processes such as healing and angiogenesis require multiple factors acting synergistically, vascular endothelial growth factor (VEGF) was then co-immobilized with the cell adhesive RGD peptide within our dextran coating through a relevant strategy featuring orientation and specificity. Altogether, both adhesive and proliferative cues could be incorporated into our construct with additive, if not synergetic, effects. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Vascular endothelial growth factor and nitric oxide synthase expression in human tooth germ development.

PubMed

Mastrangelo, F; Sberna, M T; Tettamanti, L; Cantatore, G; Tagliabue, A; Gherlone, E

2016-01-01

Vascular Endothelia Growth Factor (VEGF) and Nitric Oxide Synthase (NOS) expression, were evaluated in human tooth germs at two different stages of embryogenesis, to clarify the role of angiogenesis during tooth tissue differentiation and growth. Seventy-two third molar germ specimens were selected during oral surgery. Thirty-six were in the early stage and 36 in the later stage of tooth development. The samples were evaluated with Semi-quantitative Reverse Transcription-Polymerase chain Reaction analyses (RT-PcR), Western blot analysis (WB) and immunohistochemical analysis. Western blot and immunohistochemical analysis showed a VEGF and NOS 1-2-3 positive reaction in all samples analysed. VEGF high positive decrease reaction was observed in stellate reticulum cells, ameloblast and odontoblast clusters in early stage compared to later stage of tooth germ development. Comparable VEGF expression was observed in endothelial cells of early and advanced stage growth. NOS1 and NOS3 expressions showed a high increased value in stellate reticulum cells, and ameloblast and odontoblast clusters in advanced stage compared to early stage of development. The absence or only moderate positive reaction of NOS2 was detected in all the different tissues. Positive NOS2 expression showed in advanced stage of tissue development compared to early stage. The action of VEGF and NOS molecules are important mediators of angiogenesis during dental tissue development. VEGF high positive expression in stellate reticulum cells in the early stage of tooth development compared to the later stage and the other cell types, suggests a critical role of the stellate reticulum during dental embryo-morphogenesis.

Nrf2 Activation Induced by Sirt1 Ameliorates Acute Lung Injury After Intestinal Ischemia/Reperfusion Through NOX4-Mediated Gene Regulation.

PubMed

Chai, DongDong; Zhang, Lei; Xi, SiWei; Cheng, YanYong; Jiang, Hong; Hu, Rong

2018-01-01

Nuclear erythroid 2-related factor-2 (Nrf2) is a major stress-response transcription factor that has been implicated in regulating ischemic angiogenesis. We investigated the effects of Nrf2 in regulating revascularization and modulating acute lung injury. The expression of Nrf2 and sirtuin1 (Sirt1) was assessed in lung tissue by western blotting and immunofluorescence staining after intestinal ischemia/reperfusion (IIR) in Nrf2-/- and wild-type (WT) mice. The involvement of Nrf2 in angiogenesis, cell viability, and migration was investigated in human pulmonary microvascular endothelial cells (PMVECs). Additionally, the influence of Nrf2 expression on NOX pathway activation was measured in PMVECs after oxygen-glucose deprivation/reoxygenation. We found activation and nuclear accumulation of Nrf2 in lung tissue after IIR. Compared to IIR in WT mice, IIR in Nrf2-/- mice significantly enhanced leukocyte infiltration and collagen deposit, and inhibited endothelial cell marker CD31 expression. Nrf2 upregulation and translocation into the nucleus stimulated by Sirt1 overexpression exhibited remission of histopathologic changes and enhanced CD31 expression. Nrf2 knockdown repressed non-phagocytic cell oxidase 4 (NOX4), hypoxia-inducible factor (HIF-1α) and vascular endothelial growth factor (VEGF) expression after IIR. Nrf2 upregulation by Sirt1 enhances NOX4, HIF-1α and VEGF expression after IIR in WT mice. Furthermore, Nrf2 knockdown suppressed cell viability, capillary tube formation and cell migration in PMVECs after oxygen-glucose deprivation/reoxygenation and also inhibited NOX4, HIF-1 and VEGF expression. Moreover, NOX4 knockdown in PMVECs decreased the levels of VEGF, HIF-1α and angiogenesis. Nrf2 stimulation by Sirt1 plays an important role in sustaining angiogenic potential through NOX4-mediated gene regulation. © 2018 The Author(s). Published by S. Karger AG, Basel.

Assessment of eye bank-prepared posterior lamellar corneal tissue for endothelial keratoplasty.

PubMed

Rose, Linda; Briceño, César A; Stark, Walter J; Gloria, Dante G; Jun, Albert S

2008-02-01

To evaluate eye bank-prepared tissue for Descemet's stripping automated endothelial keratoplasty (DSAEK). Experimental study and retrospective case series. Seventeen human donor corneas and 4 recipient patients undergoing DSAEK surgery. Corneal-scleral discs were obtained. Specular microscopy and pachymetry were performed. A designated Tissue Banks International technician used a microkeratome to prepare a flap. Posterior bed thickness was measured. The sectioned tissue was stored, and at 24 and 48 hours, pachymetry was repeated. At 48 hours, specular microscopy was repeated, and endothelial cell viability was assessed with trypan blue. Descemet's stripping automated endothelial keratoplasty was performed in 4 patients using eye bank-prepared posterior lamellar tissue. Corneal tissue was assessed with the following parameters: corneal thickness measured with ultrasonic pachymetry, cell density counts measured with a keratoanalyzer, and cell viability as observed with trypan blue exclusion. Patient outcomes were measured by changes in visual acuity (VA) and the presence of a clear graft. Donor corneal pachymetry before sectioning averaged 599+/-52 microm. Immediately after sectioning with a microkeratome set at a depth of 300 microm, mean posterior bed thickness was 328+/-95 microm. Thus, the mean cutting depth achieved by the microkeratome when set at 300 micrometers averaged 271+/-83 microm. After storage for 24 hours, the posterior beds measured 352 microm, an average swelling of 24 (7%) microm (P = 0.14). After 48 hours, the posterior beds measured 382 microm, an average swelling of 54 (16%) microm (P = 0.02). Cell counts 48 hours after sectioning decreased by an average of 11% (P = 0.10). Endothelial cell staining confirmed improvement in postsectioning morphology and survival with increased technician experience. All 4 patients receiving eye bank-prepared DSAEK tissue showed uncomplicated postoperative results, with improvement in VA. The microkeratome cutting depth was moderately accurate. Pachymetry, cell density, and cell viability of sectioned tissue after 48 hours in storage were encouraging overall. Initial clinical results of eye bank-prepared DSAEK tissue showed uncomplicated postoperative courses and improved VA. Additional studies are needed to follow the long-term outcomes in the recipients of these tissues.

Quantification of STAT3 and VEGF expression for molecular diagnosis of lymph node metastasis in breast cancer

PubMed Central

Chen, Yujuan; Liu, Ya; Wang, Yu; Li, Wen; Wang, Xiaolu; Liu, Xuejuan; Chen, Yao; Ouyang, Chibin; Wang, Jing

2017-01-01

Abstract Background: Axillary lymph node metastasis is associated with increased risk of regional recurrence, distant metastasis, and poor survival in breast malignant neoplasm. Expression of signal transducer and activator of transcription 3 (STAT3) is significantly associated with tumor formation, migration, and invasion in various cancers. In addition, vascular endothelial growth factor (VEGF) expression could promote angiogenesis and increase the risk of tumorigenesis. To determine correlations among STAT3 expression, VEGF, and clinicopathological data on lymph node involvement in breast cancer patients after surgery. Methods: The mRNA expression levels of STAT3 and VEGFs were measured in 45 breast invasive ductal carcinoma tissues, 45 peritumoral tissues, and 45 adjacent nontumor tissues by real-time quantitative reverse transcription-polymerase chain reaction (RT-qPCR). Postoperative pathological examination revealed explicit axillary lymph node involvement in all patients. Results: Average mRNA levels of STAT3 and VEGFs were the highest in breast invasive ductal carcinoma tissues, followed by peritumoral tissues. High expression of STAT3 showed significant positive correlation with high axillary lymph node involvement and progesterone receptor (PR), VEGF-C, VEGF-D, and vascular endothelial growth factor receptor (VEGFR)-3 expression. The expression levels of STAT3, VEGF-C, and VEGFR-3 were significantly higher in the tumor tissues of patients with axillary lymph node metastasis than in those of patients without the metastasis. Expression levels of VEGF-C and VEGFR-3 were also significantly higher in peritumoral tissues of patients with axillary lymph node metastasis. Positive correlations were found between STAT3 and VEGF-C/-D mRNA levels. Conclusion: These data suggest that STAT3/VEGF-C/VEGFR-3 signaling pathway plays an important role in carcinogenesis and lymph-angiogenesis. Our findings suggest that STAT3 may be a potential molecular biomarker for predicting the involvement of axillary lymph nodes in breast cancer, and therapies targeting STAT3 may be important for preventing breast cancer metastasis. PMID:29137038

Vascular Endothelial Growth Factor and Angiogenesis in the Regulation of Cutaneous Wound Repair

PubMed Central

Johnson, Kelly E.; Wilgus, Traci A.

2014-01-01

Significance: Angiogenesis, the growth of new blood vessels from existing vessels, is an important aspect of the repair process. Restoration of blood flow to damaged tissues provides oxygen and nutrients required to support the growth and function of reparative cells. Vascular endothelial growth factor (VEGF) is one of the most potent proangiogenic growth factors in the skin, and the amount of VEGF present in a wound can significantly impact healing. Recent Advances: The activity of VEGF was once considered to be specific for endothelial cells lining the inside of blood vessels, partly because VEGF receptor (VEGFR) expression was believed to be restricted to endothelial cells. It is now known, however, that VEGFRs can be expressed by a variety of other cell types involved in wound repair. For example, keratinocytes and macrophages, which both carry out important functions during wound healing, express VEGFRs and are capable of responding directly to VEGF. Critical Issues: The mechanisms by which VEGF promotes angiogenesis are well established. Recent studies, however, indicate that VEGF can directly affect the activity of several nonendothelial cell types present in the skin. The implications of these extra-angiogenic effects of VEGF on wound repair are not yet known, but they suggest that this growth factor may play a more complex role during wound healing than previously believed. Future Directions: Despite the large number of studies focusing on VEGF and wound healing, it is clear that the current knowledge of how VEGF contributes to the repair of skin wounds is incomplete. Further research is needed to obtain a more comprehensive understanding of VEGF activities during the wound healing process. PMID:25302139

Astrocytic TYMP and VEGFA drive blood–brain barrier opening in inflammatory central nervous system lesions

PubMed Central

Chapouly, Candice; Tadesse Argaw, Azeb; Horng, Sam; Castro, Kamilah; Zhang, Jingya; Asp, Linnea; Loo, Hannah; Laitman, Benjamin M.; Mariani, John N.; Straus Farber, Rebecca; Zaslavsky, Elena; Nudelman, German; Raine, Cedric S.

2015-01-01

In inflammatory central nervous system conditions such as multiple sclerosis, breakdown of the blood–brain barrier is a key event in lesion pathogenesis, predisposing to oedema, excitotoxicity, and ingress of plasma proteins and inflammatory cells. Recently, we showed that reactive astrocytes drive blood–brain barrier opening, via production of vascular endothelial growth factor A (VEGFA). Here, we now identify thymidine phosphorylase (TYMP; previously known as endothelial cell growth factor 1, ECGF1) as a second key astrocyte-derived permeability factor, which interacts with VEGFA to induce blood–brain barrier disruption. The two are co-induced NFκB1-dependently in human astrocytes by the cytokine interleukin 1 beta (IL1B), and inactivation of Vegfa in vivo potentiates TYMP induction. In human central nervous system microvascular endothelial cells, VEGFA and the TYMP product 2-deoxy-d-ribose cooperatively repress tight junction proteins, driving permeability. Notably, this response represents part of a wider pattern of endothelial plasticity: 2-deoxy-d-ribose and VEGFA produce transcriptional programs encompassing angiogenic and permeability genes, and together regulate a third unique cohort. Functionally, each promotes proliferation and viability, and they cooperatively drive motility and angiogenesis. Importantly, introduction of either into mouse cortex promotes blood–brain barrier breakdown, and together they induce severe barrier disruption. In the multiple sclerosis model experimental autoimmune encephalitis, TYMP and VEGFA co-localize to reactive astrocytes, and correlate with blood–brain barrier permeability. Critically, blockade of either reduces neurologic deficit, blood–brain barrier disruption and pathology, and inhibiting both in combination enhances tissue preservation. Suggesting importance in human disease, TYMP and VEGFA both localize to reactive astrocytes in multiple sclerosis lesion samples. Collectively, these data identify TYMP as an astrocyte-derived permeability factor, and suggest TYMP and VEGFA together promote blood–brain barrier breakdown. PMID:25805644

In vitro 3D regeneration-like growth of human patient brain tissue.

PubMed

Tang-Schomer, M D; Wu, W B; Kaplan, D L; Bookland, M J

2018-05-01

In vitro culture of primary neurons is widely adapted with embryonic but not mature brain tissue. Here, we extended a previously developed bioengineered three-dimensional (3D) embryonic brain tissue model to resected normal patient brain tissue in an attempt to regenerate human neurons in vitro. Single cells and small sized (diameter < 100 μm) spheroids from dissociated brain tissue were seeded into 3D silk fibroin-based scaffolds, with or without collagen or Matrigel, and compared with two-dimensional cultures and scaffold-free suspension cultures. Changes of cell phenotypes (neuronal, astroglial, neural progenitor, and neuroepithelial) were quantified with flow cytometry and analyzed with a new method of statistical analysis specifically designed for percentage comparison. Compared with a complete lack of viable cells in conventional neuronal cell culture condition, supplements of vascular endothelial growth factor-containing pro-endothelial cell condition led to regenerative growth of neurons and astroglial cells from "normal" human brain tissue of epilepsy surgical patients. This process involved delayed expansion of Nestin+ neural progenitor cells, emergence of TUJ1+ immature neurons, and Vimentin+ neuroepithelium-like cell sheet formation in prolonged cultures (14 weeks). Micro-tissue spheroids, but not single cells, supported the brain tissue growth, suggesting importance of preserving native cell-cell interactions. The presence of 3D scaffold, but not hydrogel, allowed for Vimentin+ cell expansion, indicating a different growth mechanism than pluripotent cell-based brain organoid formation. The slow and delayed process implied an origin of quiescent neural precursors in the neocortex tissue. Further optimization of the 3D tissue model with primary human brain cells could provide personalized brain disease models. Copyright © 2018 John Wiley & Sons, Ltd.

ACE/DD genotype is associated with hemostasis balance disturbances reflecting hypercoagulability and endothelial dysfunction in patients with untreated hypertension.

PubMed

Makris, T K; Stavroulakis, G A; Dafni, U G; Gialeraki, A E; Krespi, P G; Hatzizacharias, A N; Tsoukala, C G; Vythoulkas, J S; Kyriakidis, M K

2000-11-01

Angiotensin-converting enzyme (ACE) gene polymorphism has been associated with an increased incidence of myocardial infarction. Recent studies have investigated a potential influence of ACE gene polymorphism on fibrinolysis or endothelial function. It has been previously established that essential hypertension is accompanied by endothelial dysfunction and fibrinolytic balance disorders. The aim of our study was to study the relation between ACE gene polymorphism and fibrinolytic/hemostatic factors as well as endothelial cell damage markers in patients with hypertension. The following parameters were evaluated in 104 patients with previously untreated hypertension: plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (tPA) antigen, fibrinogen, D-dimer, and von Willebrand factor (vWF). The genotype of the ACE gene was also determined (by the polymerase chain reaction method), and patients were characterized according to the observed alleles as deletion/deletion (DD), insertion/insertion (II), or insertion/deletion (ID). Those with DD genotype (n = 42) had significantly higher plasma levels of PAI-1 antigen (P =. 012), tPA antigen (P =.0001), fibrinogen (P =.0002), D-dimer (P =. 0001) and vWF (P =.0004) compared with ID (n = 30) or II (n = 32) genotypes. The ACE gene genotypes appeared to be significant predictors for plasma PAI-1 antigen, tPA antigen, fibrinogen, D -dimer, and vWF even after adjustment for age, sex, body mass index, triglyceride and cholesterol levels, and blood pressure. Our findings suggest that the ACE/DD genotype is associated with hemostasis balance disturbances reflecting hypercoagulability and endothelial damage in patients with untreated hypertension.

Endothelial NOS is required for SDF-1alpha/CXCR4-mediated peripheral endothelial adhesion of c-kit+ bone marrow stem cells.

PubMed

Kaminski, Alexander; Ma, Nan; Donndorf, Peter; Lindenblatt, Nicole; Feldmeier, Gregor; Ong, Lee-Lee; Furlani, Dario; Skrabal, Christian A; Liebold, Andreas; Vollmar, Brigitte; Steinhoff, Gustav

2008-01-01

In the era of intravascular approaches for regenerative cell therapy, the underlying mechanisms of stem cell migration to non-marrow tissue have not been clarified. We hypothesized that next to a local inflammatory response implying adhesion molecule expression, endothelial nitric oxide synthase (eNOS)-dependent signaling is required for stromal- cell-derived factor-1 alpha (SDF-1alpha)-induced adhesion of c-kit+ cells to the vascular endothelium. SDF-1alpha/tumor necrosis factor-alpha (TNF-alpha)-induced c-kit+-cell shape change and migration capacity was studied in vitro using immunohistochemistry and Boyden chamber assays. In vivo interaction of c-kit+ cells from bone marrow with the endothelium in response to SDF-1alpha/TNF-alpha stimulation was visualized in the cremaster muscle microcirculation of wild-type (WT) and eNOS (-/-) mice using intravital fluorescence microscopy. In addition, NOS activity was inhibited with N-nitro-L-arginine-methylester-hydrochloride in WT mice. To reveal c-kit+-specific adhesion behavior, endogenous leukocytes (EL) and c-kit+ cells from peripheral blood served as control. Moreover, intercellular adhesion molecule-1 (ICAM-1) and CXCR4 were blocked systemically to determine their role in inflammation-related c-kit+-cell adhesion. In vitro, SDF-1alpha enhanced c-kit+-cell migration. In vivo, SDF-1alpha alone triggered endothelial rolling-not firm adherence-of c-kit+ cells in WT mice. While TNF-alpha alone had little effect on adhesion of c-kit+ cells, it induced maximum endothelial EL adherence. However, after combined treatment with SDF-1alpha+TNF-alpha, endothelial adhesion of c-kit+ cells increased independent of their origin, while EL adhesion was not further incremented. Systemic treatment with anti-ICAM-1 and anti-CXCR4-monoclonal antibody completely abolished endothelial c-kit+-cell adhesion. In N-nitro-L-arginine-methylester-hydrochloride-treated WT mice as well as in eNOS (-/-) mice, firm endothelial adhesion of c-kit+ cells was entirely abrogated, while EL adhesion was significantly increased. The chemokine SDF-1alpha mediates firm adhesion c-kit+ cells only in the presence of TNF-alpha stimulation via an ICAM-1- and CXCR4-dependent mechanism. The presence of eNOS appears to be a crucial and specific factor for firm c-kit+-cell adhesion to the vascular endothelium.

Bioglass Activated Skin Tissue Engineering Constructs for Wound Healing.

PubMed

Yu, Hongfei; Peng, Jinliang; Xu, Yuhong; Chang, Jiang; Li, Haiyan

2016-01-13

Wound healing is a complicated process, and fibroblast is a major cell type that participates in the process. Recent studies have shown that bioglass (BG) can stimulate fibroblasts to secrete a multitude of growth factors that are critical for wound healing. Therefore, we hypothesize that BG can stimulate fibroblasts to have a higher bioactivity by secreting more bioactive growth factors and proteins as compared to untreated fibroblasts, and we aim to construct a bioactive skin tissue engineering graft for wound healing by using BG activated fibroblast sheet. Thus, the effects of BG on fibroblast behaviors were studied, and the bioactive skin tissue engineering grafts containing BG activated fibroblasts were applied to repair the full skin lesions on nude mouse. Results showed that BG stimulated fibroblasts to express some critical growth factors and important proteins including vascular endothelial growth factor, basic fibroblast growth factor, epidermal growth factor, collagen I, and fibronectin. In vivo results revealed that fibroblasts in the bioactive skin tissue engineering grafts migrated into wound bed, and the migration ability of fibroblasts was stimulated by BG. In addition, the bioactive BG activated fibroblast skin tissue engineering grafts could largely increase the blood vessel formation, enhance the production of collagen I, and stimulate the differentiation of fibroblasts into myofibroblasts in the wound site, which would finally accelerate wound healing. This study demonstrates that the BG activated skin tissue engineering grafts contain more critical growth factors and extracellular matrix proteins that are beneficial for wound healing as compared to untreated fibroblast cell sheets.

SSeCKS/AKAP12 induces repulsion between human prostate cancer and microvessel endothelial cells through the activation of Semaphorin 3F.

PubMed

Xie, Wen; Su, Wei; Zhang, Lijuan; Shang, Qingkun; Su, Bing

2017-09-02

Metastasis remains the primary cause of prostate cancer related death. Cancer cells need to contact endothelial cells and disrupt endothelial junctions to cross the endothelium for invasion and metastasis. The suppression of heterotypic repulsion between cancer and endothelial cells allows cancer cells to invade into the surrounding tissue. Here, we demonstrate that SSeCKS/AKAP12 induced repulsion between human prostate cancer and microvessel endothelial cells, which was mediated by an angiogenesis inhibitor Semaphorin 3F. Moreover, we examined AKAP12 and Semaphorin 3F mRNA expression in 42 prostate cancer and 30 benign prostatic hyperplasia tissue samples, and found that the expression of AKAP12 and Semaphorin 3F mRNA was inversely associated with the degree of aggressiveness of prostate cancer cells and tissues. An ordinal logistic regression analysis indicates that there is a positive association between the expression of AKAP12 and Semaphorin 3F in prostate cancer, suggesting that the activation of Semaphorin 3F by SSeCKS/AKAP12 may be involved in prostate cancer progression and metastasis. Copyright © 2017 Elsevier Inc. All rights reserved.

Macrophages in tissue repair, regeneration, and fibrosis

PubMed Central

Wynn, Thomas A.; Vannella, Kevin M.

2016-01-01

Inflammatory monocytes and resident tissue macrophages are key regulators of tissue repair, regeneration, and fibrosis. Following tissue injury, monocytes and macrophages undergo marked phenotypic and functional changes to play critical roles during the initiation, maintenance, and resolution phases of tissue repair. Disturbances in macrophage function can lead to aberrant repair, with uncontrolled inflammatory mediator and growth factor production, deficient generation of anti-inflammatory macrophages, or failed communication between macrophages and epithelial cells, endothelial cells, fibroblasts, and stem or tissue progenitor cells all contributing to a state of persistent injury, which may lead to the development of pathological fibrosis. In this review, we discuss the mechanisms that instruct macrophages to adopt pro-inflammatory, pro-wound healing, pro-fibrotic, anti-inflammatory, anti-fibrotic, pro-resolving, and tissue regenerating phenotypes following injury, and highlight how some of these mechanisms and macrophage activation states could be exploited therapeutically. PMID:26982353

Cell sheet-based tissue engineering for fabricating 3-dimensional heart tissues.

PubMed

Shimizu, Tatsuya

2014-01-01

In addition to stem cell biology, tissue engineering is an essential research field for regenerative medicine. In contrast to cell injection, bioengineered tissue transplantation minimizes cell loss and has the potential to repair tissue defects. A popular approach is scaffold-based tissue engineering, which utilizes a biodegradable polymer scaffold for seeding cells; however, new techniques of cell sheet-based tissue engineering have been developed. Cell sheets are harvested from temperature-responsive culture dishes by simply lowering the temperature. Monolayer or stacked cell sheets are transplantable directly onto damaged tissues and cell sheet transplantation has already been clinically applied. Cardiac cell sheet stacking produces pulsatile heart tissue; however, lack of vasculature limits the viable tissue thickness to 3 layers. Multistep transplantation of triple-layer cardiac cell sheets cocultured with endothelial cells has been used to form thick vascularized cardiac tissue in vivo. Furthermore, in vitro functional blood vessel formation within 3-dimensional (3D) tissues has been realized by successfully imitating in vivo conditions. Triple-layer cardiac cell sheets containing endothelial cells were layered on vascular beds and the constructs were media-perfused using novel bioreactor systems. Interestingly, cocultured endothelial cells migrate into the vascular beds and form perfusable blood vessels. An in vitro multistep procedure has also enabled the fabrication of thick, vascularized heart tissues. Cell sheet-based tissue engineering has revealed great potential to fabricate 3D cardiac tissues and should contribute to future treatment of severe heart diseases and human tissue model production.

Tissue Engineering Research

DTIC Science & Technology

2002-01-01

al. 1999; Petersen et al. 1999); the differentiation (Pittenger et al. 1999) and clinical use of mesenchymal stem cells (Osiris Therapeutics...endothelialization of vascular prostheses, and use of mesenchymal stem cells for bone repair. Current Condition Factors determining cell source and design...the use of mesenchymal stem cells for bone repair. The UK has taken an active interest in further research on the use of ES cells . This is aided by

Effect of Diabetes Mellitus on Adipocyte-Derived Stem Cells in Rat.

PubMed

Jumabay, Medet; Moon, Jeremiah H; Yeerna, Huwate; Boström, Kristina I

2015-11-01

Diabetes mellitus affects the adipose tissue and mesenchymal stem cells derived from the adipose stroma and other tissues. Previous reports suggest that bone morphogenetic protein 4 (BMP4) is involved in diabetic complications, at the same time playing an important role in the maintenance of stem cells. In this study, we used rats transgenic for human islet amyloid polypeptide (HIP rats), a model of type 2 diabetes, to study the effect of diabetes on adipocyte-derived stem cells, referred to as dedifferentiated fat (DFAT) cells. Our results show that BMP4 expression in inguinal adipose tissue is significantly increased in HIP rats compared to controls, whereas matrix Gla protein (MGP), an inhibitor of BMP4 is decreased as determined by quantitative PCR, and immunofluorescence. In addition, adipose vascularity and expression of multiple endothelial cell markers was increased in the diabetic tissue, visualized by immunofluorescence for endothelial markers. The endothelial markers co-localized with the enhanced BMP4 expression, suggesting that vascular cells play a role BMP4 induction. The DFAT cells are multipotent stem cells derived from white mature adipocytes that undergo endothelial and adipogenic differentiation. DFAT cells prepared from the inguinal adipose tissue in HIP rats exhibited enhanced proliferative capacity compared to wild type. In addition, their ability to undergo both endothelial cell and adipogenic lineage differentiation was enhanced, as well as their response to BMP4, as assessed by lineage marker expression. We conclude that the DFAT cells are affected by diabetic changes and may contribute to the adipose dysfunction in diabetes. © 2015 Wiley Periodicals, Inc.

Quantitative Analysis of Endothelial Cell Loss in Preloaded Descemet Membrane Endothelial Keratoplasty Grafts.

PubMed

Wolle, Meraf A; DeMill, David L; Johnson, Lauren; Lentz, Stephen I; Woodward, Maria A; Mian, Shahzad I

2017-11-01

Availability of preloaded Descemet membrane endothelial keratoplasty (pDMEK) tissue may increase acceptance of DMEK in surgical management of endothelial disease. The goal of this study was to determine the safety of pDMEK grafts for 24 hours before surgery by analyzing endothelial cell loss (ECL) using 2 image analysis software programs. A total of 18 cadaveric corneas were prepared for DMEK using a standardized technique and loaded in a modified Jones tube injector. Nine of the corneas were injected into Calcein AM vital dye after 1 minute (controls), and the remaining 9 corneas were left preloaded for 24 hours before injection into vital dye for staining. The stained corneas were imaged using an inverted confocal microscope. ECL was then analyzed and quantified by 2 different graders using 2 image analysis software programs. The control DMEK tissue resulted in 22.0% ± 4.0% ECL compared with pDMEK tissue, which resulted in 19.2% ± 7.2% ECL (P = 0.31). Interobserver agreement was 0.93 for MetaMorph and 0.92 for Fiji. The average time required to process images with MetaMorph was 2 ± 1 minutes and with Fiji was 20 ± 10 minutes. Intraobserver agreement was 0.97 for MetaMorph and 0.93 for Fiji. Preloading DMEK tissue is safe and may provide an alternative technique for tissue distribution and surgery for DMEK. The use of MetaMorph software for quantifying ECL is a novel and accurate imaging method with increased efficiency and reproducibility compared with the previously validated Fiji.

Platelet released growth factors boost expansion of bone marrow derived CD34(+) and CD133(+) endothelial progenitor cells for autologous grafting.

PubMed

Lippross, Sebastian; Loibl, Markus; Hoppe, Sven; Meury, Thomas; Benneker, Lorin; Alini, Mauro; Verrier, Sophie

2011-01-01

Stem cell based autologous grafting has recently gained mayor interest in various surgical fields for the treatment of extensive tissue defects. CD34(+) and CD133(+) cells that can be isolated from the pool of bone marrow mononuclear cells (BMC) are capable of differentiating into mature endothelial cells in vivo. These endothelial progenitor cells (EPC) are believed to represent a major portion of the angiogenic regenerative cells that are released from bone marrow when tissue injury has occurred. In recent years tissue engineers increasingly looked at the process of vessel neoformation because of its major importance for successful cell grafting to replace damaged tissue. Up to now one of the greatest problems preventing a clinical application is the large scale of expansion that is required for such purpose. We established a method to effectively enhance the expansion of CD34(+) and CD133(+) cells by the use of platelet-released growth factors (PRGF) as a media supplement. PRGF were prepared from thrombocyte concentrates and used as a media supplement to iscove's modified dulbecco's media (IMDM). EPC were immunomagnetically separated from human bone morrow monocyte cells and cultured in IMDM + 10% fetal calf serum (FCS), IMDM + 5%, FCS + 5% PRGF and IMDM + 10% PRGF. We clearly demonstrate a statistically significant higher and faster cell proliferation rate at 7, 14, 21, and 28 days of culture when both PRGF and FCS were added to the medium as opposed to 10% FCS or 10% PRGF alone. The addition of 10% PRGF to IMDM in the absence of FCS leads to a growth arrest from day 14 on. In histochemical, immunocytochemical, and gene-expression analysis we showed that angiogenic and precursor markers of CD34(+) and CD133(+) cells are maintained during long-term culture. In summary, we established a protocol to boost the expansion of CD34(+) and CD133(+) cells. Thereby we provide a technical step towards the clinical application of autologous stem cell transplantation.

The endogenous zinc finger transcription factor, ZNF24, modulates the angiogenic potential of human microvascular endothelial cells

PubMed Central

Jia, Di; Huang, Lan; Bischoff, Joyce; Moses, Marsha A.

2015-01-01

We have previously identified a zinc finger transcription factor, ZNF24 (zinc finger protein 24), as a novel inhibitor of tumor angiogenesis and have demonstrated that ZNF24 exerts this effect by repressing the transcription of VEGF in breast cancer cells. Here we focused on the role of ZNF24 in modulating the angiogenic potential of the endothelial compartment. Knockdown of ZNF24 by siRNA in human primary microvascular endothelial cells (ECs) led to significantly decreased cell migration and invasion compared with control siRNA. ZNF24 knockdown consistently led to significantly impaired VEGF receptor 2 (VEGFR2) signaling and decreased levels of matrix metalloproteinase-2 (MMP-2), with no effect on levels of major regulators of MMP-2 activity such as the tissue inhibitors of metalloproteinases and MMP-14. Moreover, silencing ZNF24 in these cells led to significantly decreased EC proliferation. Quantitative PCR array analyses identified multiple cell cycle regulators as potential ZNF24 downstream targets which may be responsible for the decreased proliferation in ECs. In vivo, knockdown of ZNF24 specifically in microvascular ECs led to significantly decreased formation of functional vascular networks. Taken together, these results demonstrate that ZNF24 plays an essential role in modulating the angiogenic potential of microvascular ECs by regulating the proliferation, migration, and invasion of these cells.— Jia, D., Huang, L., Bischoff, J., Moses, M. A. The endogenous zinc finger transcription factor, ZNF24, modulates the angiogenic potential of human microvascular endothelial cells. PMID:25550468

Von Willebrand factor regulation of blood vessel formation.

PubMed

Randi, Anna M; Smith, Koval E; Castaman, Giancarlo

2018-06-04

Several important physiological processes, from permeability to inflammation to haemostasis, take place at the vessel wall and are regulated by endothelial cells (EC). Thus, proteins that have been identified as regulators of one process are increasingly found to be involved in other vascular functions. Such is the case for Von Willebrand Factor (VWF), a large glycoprotein best known for its critical role in haemostasis. In vitro and in vivo studies have shown that lack of VWF causes enhanced vascularisation, both constitutively and following ischemia. This evidence is supported by studies on blood outgrowth endothelial cells (BOEC) from patients with lack of VWF synthesis (type 3 von Willebrand disease [VWD]). The molecular pathways are likely to involve VWF binding partners, such as integrin αvβ3, and components of Weibel Palade bodies (WPB), such as Angiopoietin-2 and Galectin-3, whose storage is regulated by VWF; these converge on the master regulator of angiogenesis and endothelial homeostasis, vascular endothelial growth factor (VEGF) signalling. Recent studies suggest that the roles of VWF may be tissue-specific. The ability of VWF to regulate angiogenesis has clinical implications for a subset of VWD patients with severe, intractable gastrointestinal bleeding due to vascular malformations. In this article, we review the evidence showing that VWF is involved in blood vessel formation, discuss the role of VWF high molecular weight multimers in regulating angiogenesis, and the value of studies on BOEC in developing a precision medicine approach to validate novel treatments for angiodysplasia in congenital VWD and acquired von Willebrand syndrome. Copyright © 2018 American Society of Hematology.

[A new possible strategy for prevention and preventive treatment of age-related macular degeneration resting on recent clinical and pathophysiological observations].

PubMed

Fischer, Tamás

2009-03-15

The beneficial effect achieved by the treatment of endothelial dysfunction in chronic cardiovascular diseases is already an evidence belonging to the basic treatment of the disease. Given the fact that the vascular system is uniform and consubstantial both physiologically, pathophysiologically and in terms of therapy, and that it plays a key role in age-related macular degeneration (AMD)--a disease leading to tragic loss of vision with its etiology and therapy being unknown--endothelial dysfunction should be treated. The pleiotropic effects of ACE-inhibitors, AR-blockers and statins and third generation beta blockers help to restitute the balance between vasodilators and vasoconstrictors in endothelial dysfunction caused by oxidative stress, the balance of growth factors and their inhibitors, pro- and anti-inflammatory substances and prothrombotic and fibrinolytic factors, inhibit the formation of oxidative stress and its harmful effects; while aspirin with its pleiotropic effects acting as an antiaggregation substance on platelets helps to set the endothelial layer back to its normal balance regarding its vasodilating, antithrombotic, antiadhesive and anti-inflammatory functions; trimetazidine as an adjuvant agent helps to normalize, to restore the disturbed metabolism of the retinal tissue functioning insufficiently, in the end. The angiotensin II receptor blocker telmisartan with its peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonist effect inhibits the development of choroidal neovascularisation (CNV) and improves it clinically favourably. The third generation beta adrenergic receptor blocker carvedilol and nebivolol as well as the peroxisome proliferator-activated receptor-gamma agonist pioglitazone elicit their antioxidant vascular protective effects mitochondrially. For the above reasons it is suggested that, as a part of long term primary and/or secondary prevention, the following groups of patients with AMD receive--taking into consideration all possible side effects--ACE-inhibitor and/or AR blocker and statin and aspirin treatment, and trimetazidine as adjuvant medicine, and third generation beta adrenergic receptor blockers: 1. those without macular degeneration but being above the age of 50 and having risk factors inducing endothelial dysfunction; 2. those, who already developed AMD in one eye as a prevention in the second, unaffected eye; and 3. those patients who developed AMD in both eyes in order to ameliorate or merely slow the progression of the disease. Besides, it is advisory and important to eliminate AMD risk factors (cardiovascular risk factors also) inducing oxidative stress with consecutive endothelial dysfunction.

Optimized adipose tissue engineering strategy based on a neo-mechanical processing method.

PubMed

He, Yunfan; Lin, Maohui; Wang, Xuecen; Guan, Jingyan; Dong, Ziqing; Feng, Lu; Xing, Malcolm; Feng, Chuanbo; Li, Xiaojian

2018-05-26

Decellularized adipose tissue (DAT) represents a promising scaffold for adipose tissue engineering. However, the unique and prolonged lipid removal process required for adipose tissue can damage extracellular matrix (ECM) constituents. Moreover, inadequate vascularization limits the recellularization of DAT in vivo. We proposed a neo-mechanical protocol for rapidly breaking adipocytes and removing lipid content from adipose tissue. The lipid-depleted adipose tissue was then subjected to a fast and mild decellularization to fabricate high-quality DAT (M-DAT). Adipose liquid extract (ALE) derived from this mechanical process was collected and incorporated into M-DAT to further optimize in vivo recellularization. Ordinary DAT was fabricated and served as a control. This developed strategy was evaluated based on decellularization efficiency, ECM quality, and recellularization efficiency. Angiogenic factor components and angiogenic potential of ALE were evaluated in vivo and in vitro. M-DAT achieved the same decellularization efficiency, but exhibited better retention of ECM components and recellularization, compared to those with ordinary DAT. Protein quantification revealed considerable levels of angiogenic factors (basic fibroblast growth factor, epidermal growth factor, transforming growth factor-β1, and vascular endothelial growth factor) in ALE. ALE promoted tube formation in vitro and induced intense angiogenesis in M-DAT in vivo; furthermore, higher expression of the adipogenic factor PPARγ and greater numbers of adipocytes were evident following ALE treatment, compared to those in the M-DAT group. Mechanical processing of adipose tissue led to the production of high-quality M-DAT and angiogenic factor-enriched ALE. The combination of ALE and M-DAT could be a promising strategy for engineered adipose tissue construction. This article is protected by copyright. All rights reserved. © 2018 by the Wound Healing Society.

Tenascin-C in the extracellular matrix promotes the selection of highly proliferative and tubulogenesis-defective endothelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alves, Tercia Rodrigues; Universidade Federal do Rio de Janeiro; Carvalho da Fonseca, Anna Carolina

2011-09-10

The extracellular matrix (ECM) contains important cues for tissue homeostasis and morphogenesis. The matricellular protein tenascin-C (TN-C) is overexpressed in remodeling tissues and cancer. In the present work, we studied the effect of different ECM-which exhibited a significant diversity in their TN-C content-in endothelial survival, proliferation and tubulogenic differentiation: autologous (endothelial) ECM devoid of TN-C, but bearing large amounts of FN; fibroblast ECM, bearing both high TN-C and FN contents; and finally, glioma-derived matrices, usually poor in FN, but very rich in TN-C. HUVECs initially adhered to the immobilized matrix produced by U373 MG glioma cells, but significantly detached andmore » died by anoikis (50 to 80%) after 24 h, as compared with cells incubated with endothelial and fibroblast matrices. Surviving endothelial cells (20 to 50%) became up to 6-fold more proliferative and formed 74-97% less tube-like structures in vitro than cells grown on non-tumoral matrices. An antibody against the EGF-like repeats of tenascin-C (TN-C) partially rescued cells from the tubulogenic defect, indicating that this molecule is responsible for the selection of highly proliferative and tubulogenic defective endothelial cells. Interestingly, by using defined substrata, in conditions that mimic glioma and normal cell ECM composition, we observed that fibronectin (FN) modulates the TN-C-induced selection of endothelial cells. Our data show that TN-C is able to modulate endothelial branching morphogenesis in vitro and, since it is prevalent in matrices of injured and tumor tissues, also suggest a role for this protein in vascular morphogenesis, in these physiological contexts.« less

Cigarette Smoke–Induced CXCR3 Receptor Up-Regulation Mediates Endothelial Apoptosis

PubMed Central

Green, Linden A.; Petrusca, Daniela; Rajashekhar, Gangaraju; Gianaris, Tom; Schweitzer, Kelly S.; Wang, Liang; Justice, Matthew J.; Petrache, Irina

2012-01-01

Endothelial monocyte–activating polypeptide II (EMAP II) and interferon-inducible protein (IP)–10 are proinflammatory mediators, which in addition to their chemokine activities, selectively induce apoptosis in endothelial cells and are up-regulated in the lungs of cigarette smoke–exposed humans. Previously, we showed that EMAP II is an essential mediator of cigarette smoke–induced lung emphysema in mice linking endothelial cell apoptosis with inflammation. Here we addressed the role of the CXCR3 receptor in EMAP II–induced and IP-10–induced apoptosis in endothelial cells and its regulation by cigarette smoke. We found that both neutralizing antibodies and small inhibitory RNA to CXCR3 abrogated EMAP II–induced and IP-10–induced endothelial caspase-3 activation and DNA fragmentation. CXCR3 receptor surface expression in human lung microvascular endothelial cells and in lung tissue endothelium was up-regulated by exposure to cigarette smoke. In tissue culture conditions, EMAP II–induced and IP-10–induced apoptosis was enhanced by preincubation with cigarette smoke extract. Interestingly, serum starvation also induced CXCR3 up-regulation and enhanced EMAP II–induced endothelial apoptosis. Signal transduction via p38 mitogen-activated protein kinase activation was essential for CXCR3-induced cell death, but not for CXCR3 receptor up-regulation by cigarette smoke. In turn, protein nitration was required for CXCR3 receptor up-regulation by cigarette smoke and consequently for subsequent CXCR3-induced cell death. In conclusion, the concerted up-regulation of proinflammatory EMAP II, IP-10, and CXCR3 by cigarette smoke could sustain a cascade of cell death that may promote the alveolar tissue loss noted in human emphysema. PMID:22936405

Tissue factor expression in rheumatoid synovium: a potential role in pannus invasion of rheumatoid arthritis.

PubMed

Chen, Lujun; Lu, Yahua; Chu, Yang; Xie, Jun; Ding, Wen'ge; Wang, Fengming

2013-09-01

Angiogenesis, as well as pannus formation within the joint, plays an important role in the erosion of articular cartilage and bone in the pathological process of rheumatoid arthritis (RA). Tissue factor (TF), an essential initiator of the extrinsic pathway of blood coagulation, is also involved in the angiogenesis and the pannus formation of RA progression. In the present study, we used immunofluorescence and confocal scanning methods to characterize TF immunolocalization in RA synovium. We showed that positive staining of TF could be immunolocalized in synoviocytes, CD19(+) B cells and CD68(+) macrophages, whereas weak or negative staining of tissue factor could be found in CD34(+) endothelial cells of neo-vessels, CD3(+) T cells and CD14(+) monocytes in RA synovium tissues. Our study demonstrates a detailed local expression of TF in the rheumatoid synovium, and supports the notion that TF, expressed not only by the synoviocytes themselves, but also the infiltrating CD19(+) B cells and CD68(+) macrophages, is involved in the pannus invasion in the progression of rheumatoid arthritis. Copyright © 2013 Elsevier GmbH. All rights reserved.

Calcium-Alginate Hydrogel-Encapsulated Fibroblasts Provide Sustained Release of Vascular Endothelial Growth Factor

PubMed Central

Hunt, Nicola C.; Shelton, Richard M.; Henderson, Deborah J.

2013-01-01

Vascularization of engineered or damaged tissues is essential to maintain cell viability and proper tissue function. Revascularization of the left ventricle (LV) of the heart after myocardial infarction is particularly important, since hypoxia can give rise to chronic heart failure due to inappropriate remodeling of the LV after death of cardiomyocytes (CMs). Fibroblasts can express vascular endothelial growth factor (VEGF), which plays a major role in angiogenesis and also acts as a chemoattractant and survival factor for CMs and cardiac progenitors. In this in vitro model study, mouse NIH 3T3 fibroblasts encapsulated in 2% w/v Ca-alginate were shown to remain viable for 150 days. Semiquantitative reverse transcription–polymerase chain reaction and immunohistochemistry demonstrated that over 21 days of encapsulation, fibroblasts continued to express VEGF, while enzyme-linked immunosorbent assay showed that there was sustained release of VEGF from the Ca-alginate during this period. The scaffold degraded gradually over the 21 days, without reduction in volume. Cells released from the Ca-alginate at 7 and 21 days as a result of scaffold degradation were shown to retain viability, to adhere to fibronectin in a normal manner, and continue to express VEGF, demonstrating their potential to further contribute to maintenance of cardiac function after scaffold degradation. This model in vitro study therefore demonstrates that fibroblasts encapsulated in Ca-alginate provide sustained release of VEGF. PMID:23082964

Effect of peritoneal dialysis on expression of vascular endothelial growth factor, basic fibroblast growth factor and endostatin of the peritoneum in peritoneal dialysis patients.

PubMed

Gao, Dan; Zhao, Zhan-Zheng; Liang, Xian-Hui; Li, Yan; Cao, Ying; Liu, Zhang-Suo

2011-11-01

The aim of this study is to investigate the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and endostatin (ES) in human peritoneum and investigate the relationship between them and peritoneum neoangiogensis in the patients with uraemia and peritoneal dialysis (PD). Peritoneal biopsies were obtained from normal subjects (n = 8), uraemic predialysis patients (n = 12) and PD patients (n = 10). The mRNA expression of VEGF, bFGF and ES in peritoneal tissues were measured through real-time polymerase chain reaction. The protein expression of VEGF, bFGF and ES in peritoneal tissues were determined through western blot. Microvessel density (MVD) of peritoneal tissue was assessed using immunohistochemistry with CD34 monoclonal antibody. The mRNA and protein of VEGF, bFGF and ES were expressed in all peritoneal samples. Compared with the normal control group, the mRNA and protein expression of VEGF and bFGF in peritoneal tissues were all significantly upregulated in the uraemic predialysis and PD group (all P < 0.05). Compared with the normal control group, the protein expression of ES were significantly upregulated in the uraemic predialysis and PD group (all (P < 0.05), but the mRNA expression of ES did not have obvious differences in the uraemic predialysis and PD group as compared to the normal control group (P > 0.05). MVD of peritoneal tissue were increased in the uraemic predialysis and PD group compared with the normal group (all P < 0.05). A significant positive correlation was found between VEGF mRNA expression and MVD, bFGF mRNA expression and MVD. The mRNA expression of VEGF and bFGF, the protein expression of VEGF, bFGF, and ES and microvessel density (MVD) are increased both in the uraemic predialysis and PD patients. These results show that uraemia circumstances and non-physiological compatibility of peritoneal dialysis solution might increase VEGF, bFGF and ES expression and MVD, which might participate in the increment of the peritoneum neoangiogensis and ultrafiltration failure in PD patients. © 2011 The Authors. Nephrology © 2011 Asian Pacific Society of Nephrology.

Vacuum-assisted closure therapy increases local interleukin-8 and vascular endothelial growth factor levels in traumatic wounds.

PubMed

Labler, Ludwig; Rancan, Mario; Mica, Ladislav; Härter, Luc; Mihic-Probst, Daniela; Keel, Marius

2009-03-01

Clinical observations are suggesting accelerated granulation tissue formation in traumatic wounds treated with vacuum-assisted closure (VAC). Aim of this study was to determine the impact of VAC therapy versus alternative Epigard application on local inflammation and neovascularization in traumatic soft tissue wounds. Thirty-two patients with traumatic wounds requiring temporary coverage (VAC n = 16; Epigard n = 16) were included. At each change of dressing, samples of wound fluid and serum were collected (n = 80). The cytokines interleukin (IL)-6, IL-8, vascular endothelial growth factor (VEGF), and fibroblast growth factor-2 were measured by ELISA. Wound biopsies were examined histologically for inflammatory cells and degree of neovascularization present. All cytokines were found to be elevated in wound fluids during both VAC and Epigard treatment, whereas serum concentrations were negligible or not detectable. In wound fluids, significantly higher IL-8 (p < 0.001) and VEGF (p < 0.05) levels were detected during VAC therapy. Furthermore, histologic examination revealed increased neovascularization (p < 0.05) illustrated by CD31 and von Willebrand factor immunohistochemistry in wound biopsies of VAC treatment. In addition, there was an accumulation of neutrophils as well as an augmented expression of VEGF (p < 0.005) in VAC wound biopsies. This study suggests that VAC therapy of traumatic wounds leads to increased local IL-8 and VEGF concentrations, which may trigger accumulation of neutrophils and angiogenesis and thus, accelerate neovascularization.

N-Isopropylacrylamide-co-glycidylmethacrylate as a Thermoresponsive Substrate for Corneal Endothelial Cell Sheet Engineering

PubMed Central

Madathil, Bernadette K.; Anil Kumar, Pallickaveedu RajanAsari; Kumary, Thrikkovil Variyath

2014-01-01

Endothelial keratoplasty is a recent shift in the surgical treatment of corneal endothelial dystrophies, where the dysfunctional endothelium is replaced whilst retaining the unaffected corneal layers. To overcome the limitation of donor corneal shortage, alternative use of tissue engineered constructs is being researched. Tissue constructs with intact extracellular matrix are generated using stimuli responsive polymers. In this study we evaluated the feasibility of using the thermoresponsive poly(N-isopropylacrylamide-co-glycidylmethacrylate) polymer as a culture surface to harvest viable corneal endothelial cell sheets. Incubation below the lower critical solution temperature of the polymer allowed the detachment of the intact endothelial cell sheet. Phase contrast and scanning electron microscopy revealed the intact architecture, cobble stone morphology, and cell-to-cell contact in the retrieved cell sheet. Strong extracellular matrix deposition was also observed. The RT-PCR analysis confirmed functionally active endothelial cells in the cell sheet as evidenced by the positive expression of aquaporin 1, collagen IV, Na+-K+ ATPase, and FLK-1. Na+-K+ ATPase protein expression was also visualized by immunofluorescence staining. These results suggest that the in-house developed thermoresponsive culture dish is a suitable substrate for the generation of intact corneal endothelial cell sheet towards transplantation for endothelial keratoplasty. PMID:25003113

Pulsed high oxygen induces a hypoxic-like response in human umbilical endothelial cells and in humans.

PubMed

Cimino, F; Balestra, C; Germonpré, P; De Bels, D; Tillmans, F; Saija, A; Speciale, A; Virgili, F

2012-12-01

It has been proposed that relative changes of oxygen availability, rather than steady-state hypoxic or hyperoxic conditions, play an important role in hypoxia-inducible factor (HIF) transcriptional effects. According to this hypothesis describing the "normobaric oxygen paradox", normoxia following a hyperoxic event is sensed by tissues as an oxygen shortage, upregulating HIF-1 activity. With the aim of confirming, at cellular and at functional level, that normoxia following a hyperoxic event is "interpreted" as a hypoxic event, we report a combination of experiments addressing the effects of an intermittent increase of oxygen concentration on HIF-1 levels and the activity level of specific oxygen-modulated proteins in cultured human umbilical vein endothelial cells and the effects of hemoglobin levels after intermittent breathing of normobaric high (100%) and low (15%) oxygen in vivo in humans. Our experiments confirm that, during recovery after hyperoxia, an increase of HIF expression occurs in human umbilical vein endothelial cells, associated with an increase of matrix metalloproteinases activity. These data suggest that endothelial cells "interpret" the return to normoxia after hyperoxia as a hypoxic stimulus. At functional level, our data show that breathing both 15 and 100% oxygen 30 min every other day for a period of 10 days induces an increase of hemoglobin levels in humans. This effect was enhanced after the cessation of the oxygen breathing. These results indicate that a sudden decrease in tissue oxygen tension after hyperoxia may act as a trigger for erythropoietin synthesis, thus corroborating the hypothesis that "relative" hypoxia is a potent stimulator of HIF-mediated gene expressions.

Evidence for CXCL16 as a potent angiogenic mediator and endothelial progenitor cell chemotactic factor

PubMed Central

Isozaki, Takeo; Arbab, Ali S.; Haas, Christian S.; Amin, M. Asif; Arendt, Monica D.; Koch, Alisa E.; Ruth, Jeffrey H.

2013-01-01

Background We examined the possibility that CXCL16 recruits endothelial cells (ECs) to developing neovasculature in rheumatoid arthritis (RA) synovium. Methods We utilized the RA synovial tissue (ST) severe combined immunodeficient (SCID) mouse chimera system to examine human dermal microvascular endothelial cell (HMVEC) and human endothelial progenitor cell (EPC) recruitment into engrafted human synovium injected intragraft with RA synovial fluid (SF) immunodepleted of CXCL16. CXCR6 deficient (CXCR6−/−) and wild-type (Wt) C57BL/6 mice were primed to develop K/BxN serum induced arthritis and evaluated for angiogenesis. HMVECs and EPCs from human cord blood were also examined for CXCR6 expression by immunofluorescence and signaling activity for CXCL16. Results We found that CXCR6 is prominently expressed on human EPCs and HMVECs and can be upregulated by interleukin-1β (IL-1β). SCID mice injected intragraft with RA SF immunodepleted of CXCL16 showed a significant reduction in EPC recruitment. Using the K/BxN serum induced inflammatory arthritis model, CXCR6−/− mice showed profound reductions in hemoglobin (Hb) levels that correlated with reductions in monocyte and T-cell recruitment to arthritic joint tissue in CXCR6−/− compared to wildtype (Wt) mice. We also found that HMVECs and EPCs respond to CXCL16 stimulation but have unique signal transduction pathways and homing properties. Conclusion These results indicate that CXCL16 and its receptor CXCR6 may be a central ligand-receptor pair that can be highly correlated with EPC recruitment and blood vessel formation in the RA joint. PMID:23633118

Proangiogenic hematopoietic cells of monocytic origin: roles in vascular regeneration and pathogenic processes of systemic sclerosis.

PubMed

Yamaguchi, Yukie; Kuwana, Masataka

2013-02-01

New blood vessel formation is critical, not only for organ development and tissue regeneration, but also for various pathologic processes, such as tumor development and vasculopathy. The maintenance of the postnatal vascular system requires constant remodeling, which occurs through angiogenesis, vasculogenesis, and arteriogenesis. Vasculogenesis is mediated by the de novo differentiation of mature endothelial cells from endothelial progenitor cells (EPCs). Early studies provided evidence that bone marrow-derived CD14⁺ monocytes can serve as a subset of EPCs because of their expression of endothelial markers and ability to promote neovascularization in vitro and in vivo. However, the current consensus is that monocytic cells do not give rise to endothelial cells in vivo, but function as support cells, by promoting vascular formation and repair through their immediate recruitment to the site of vascular injury, secretion of proangiogenic factors, and differentiation into mural cells. These monocytes that function in a supporting role in vascular repair are now termed monocytic pro-angiogenic hematopoietic cells (PHCs). Systemic sclerosis (SSc) is a multisystem connective tissue disease characterized by excessive fibrosis and microvasculopathy, along with poor vascular formation and repair. We recently showed that in patients with SSc, circulating monocytic PHCs increase dramatically and have enhanced angiogenic potency. These effects may be induced in response to defective vascular repair machinery. Since CD14⁺ monocytes can also differentiate into fibroblast-like cells that produce extracellular matrix proteins, here we propose a new hypothesis that aberrant monocytic PHCs, once mobilized into circulation, may also contribute to the fibrotic process of SSc.

Co-delivery of vascular endothelial growth factor and angiopoietin-1 using injectable microsphere/hydrogel hybrid systems for therapeutic angiogenesis.

PubMed

Shin, Seung-Hwa; Lee, Jangwook; Ahn, Dong-Gyun; Lee, Kuen Yong

2013-08-01

We hypothesized that combined delivery of vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) using microsphere/hydrogel hybrid systems could enhance mature vessel formation compared with administration of each factor alone. Hybrid delivery systems composed of alginate hydrogels and poly(D,L-lactic-co-glycolic acid) (PLGA) microspheres containing angiogenic factors were prepared. The release behavior of angiogenic factors from hybrid systems was monitored in vitro. The hybrid systems were injected into an ischemic rodent model, and blood vessel formation at the ischemic site was evaluated. The sustained release over 4 weeks of both VEGF and Ang-1 from hybrid systems was achieved in vitro. Co-delivery of VEGF and Ang-1 was advantageous to retain muscle tissues and significantly induced vessel enlargement at the ischemic site, compared to mice treated with either VEGF or Ang-1 alone. Sustained and combined delivery of VEGF and Ang-1 significantly enhances vessel enlargement at the ischemic site, compared with sustained delivery of either factor alone. Microsphere/hydrogel hybrid systems may be a promising vehicle for delivery of multiple drugs for many therapeutic applications.

Heterogeneity of proangiogenic features in mesenchymal stem cells derived from bone marrow, adipose tissue, umbilical cord, and placenta.

PubMed

Du, Wen Jing; Chi, Ying; Yang, Zhou Xin; Li, Zong Jin; Cui, Jun Jie; Song, Bao Quan; Li, Xue; Yang, Shao Guang; Han, Zhi Bo; Han, Zhong Chao

2016-11-10

Mesenchymal stem cells (MSCs) have been widely proven effective for therapeutic angiogenesis in ischemia animal models as well as clinical vascular diseases. Because of the invasive method, limited resources, and aging problems of adult tissue-derived MSCs, more perinatal tissue-derived MSCs have been isolated and studied as promising substitutable MSCs for cell transplantation. However, fewer studies have comparatively studied the angiogenic efficacy of MSCs derived from different tissues sources. Here, we evaluated whether the in-situ environment would affect the angiogenic potential of MSCs. We harvested MSCs from adult bone marrow (BMSCs), adipose tissue (AMSCs), perinatal umbilical cord (UMSCs), and placental chorionic villi (PMSCs), and studied their "MSC identity" by flow cytometry and in-vitro trilineage differentiation assay. Then we comparatively studied their endothelial differentiation capabilities and paracrine actions side by side in vitro. Our data showed that UMSCs and PMSCs fitted well with the minimum standard of MSCs as well as BMSCs and AMSCs. Interestingly, we found that MSCs regardless of their tissue origins could develop similar endothelial-relevant functions in vitro, including producing eNOS and uptaking ac-LDL during endothelial differentiation in spite of their feeble expression of endothelial-related genes and proteins. Additionally, we surprisingly found that BMSCs and PMSCs could directly form tubular structures in vitro on Matrigel and their conditioned medium showed significant proangiogenic bioactivities on endothelial cells in vitro compared with those of AMSCs and UMSCs. Besides, several angiogenic genes were upregulated in BMSCs and PMSCs in comparison with AMSCs and UMSCs. Moreover, enzyme-linked immunosorbent assay further confirmed that BMSCs secreted much more VEGF, and PMSCs secreted much more HGF and PGE2. Our study demonstrated the heterogeneous proangiogenic properties of MSCs derived from different tissue origins, and the in vivo isolated environment might contribute to these differences. Our study suggested that MSCs derived from bone marrow and placental chorionic villi might be preferred in clinical application for therapeutic angiogenesis.

Botulinum toxin A improves adipose tissue engraftment by promoting cell proliferation, adipogenesis and angiogenesis

PubMed Central

Tang, Qi; Chen, Chang; Wang, Xiaqi; Li, Wei; Zhang, Yan; Wang, Muyao; Jing, Wei; Wang, Hang; Guo, Weihua; Tian, Weidong

2017-01-01

Adipose tissue engraftment has become a well-established therapy in plastic and reconstructive surgery used to restore age-related or injury-related soft tissue loss. However, the unpredictable absorption rates limit its further application. Some clinicians have noted that more optimal aesthetic results are achieved when botulinum toxin A (BoNTA) is applied prior to adipose tissue grafting. In the present study, we transplanted allogeneic adipose tissue treated with or without BoNTA in SD rats in vivo. We subsequently evaluated the survival rate (weight, volume, apoptosis and cellular integrity) and revascularization of the adipose tissue. The results revealed that BoNTA improved the long-term weight and volume retention of the graft, and preserved cellular integrity. BoNTA significantly increased the expression levels of CD31 and vascular endothelial growth factor (VEGF), suggesting enhanced vasodilation and endothelial cell proliferation. In vitro, adipose-derived stem cells (ASCs) were isolated, identified and induced to proliferate and differentiate with or without BoNTA. Furthermore, to evaluate the proliferative, adipogenic and angiogenic ability of the ASCs, CCK-8 assay and Oil Red O staining were conducted. Gene and protein expression levels were analyzed by RT-qPCR and western blot analysis. The results revealed that 8×10−2 U/ml BoNTA as the optimal dose increased ASC proliferation and adipogenic differentiation capacity, as well as the expression level of the key cytokine of angiogenesis. On the whole, our findings indicate that BoNTA improves adipose tissue engraftment and promotes ASC regeneration, which could benefit future clinical applications. PMID:28731141

Expression of angiogenic factors and plexiform lesions in the lungs of broiler and layer chickens: A comparison.

PubMed

Tan, X; Shao, F-J; Fan, G-J; Ying, Y-T

2018-05-01

Plexiform lesions are characteristic histological changes of pulmonary arteries in human patients with severe pulmonary arterial hypertension (PAH) and are regarded as angiogenic lesions. Meat-type broiler chickens are susceptible to PAH and can develop plexiform lesions spontaneously. Whether the lesion development in broilers is associated with PAH predisposition and lung angiogenic environment remains unclear. Moreover, little is known about the cellular origin of these structures. In this work, plexiform lesions were detected in both layer chickens (a strain known to be resistant to PAH) and broiler chickens aged between 1 and 6 wk with normal pulmonary arterial pressures. Within each of the sampled ages, the lesion density did not differ between strains, with an exception of wk 4 when broiler was higher than layer. In contrast to the trend of age-related decline in layers, lesion densities in broilers demonstrated bi-phasic alterations characterized by a gradual decrease during wk 1 to 3 followed by a sudden increase at wk 4. The mRNA of 6 angiogenic factors in the lung tissue, namely, vascular endothelial growth factor receptor (VEGFR)-2, angiopoietin (Ang)-1, angiopoietin receptor Tie-2, transforming growth factor (TGF)-β1, hepatocyte growth factor (HGF), and interleukin (IL)-8, were differentially expressed between strains. However, none of them was found to be significantly correlated with the lesion density by strain and age-adjusted partial correlation analysis. An in vivo experiment revealed impaired differentiation of endothelial progenitor cells (EPC) into endothelial cells during the producing of plexiform lesions, as evidenced by increased expression of endothelial CD133, a maker of EPC, but reduced expression of CD31, a marker of mature endothelial cells, in the parent vessels of plexiform lesions compared to normal vessels. Collectively, it appears unlikely that the predisposition to PAH or intrapulmonary angiogenic environment contributes to the lesion development in broilers when compared with layers. It is suggested that the lesion development is associated with increased pulmonary arterial pressure, and that local EPC dysfunction may play a role in the process.

Molecular controls of arterial morphogenesis

PubMed Central

Simons, Michael; Eichmann, Anne

2015-01-01

Formation of arterial vasculature, here termed arteriogenesis, is a central process in embryonic vascular development as well as in adult tissues. While the process of capillary formation, angiogenesis, is relatively well understood, much remains to be learned about arteriogenesis. Recent discoveries point to the key role played by vascular endothelial growth factor receptor 2 (VEGFR2) in control of this process and to newly identified control circuits that dramatically influence its activity. The latter can present particularly attractive targets for a new class of therapeutic agents capable of activation of this signaling cascade in a ligand-independent manner, thereby promoting arteriogenesis in diseased tissues. PMID:25953926

Integrative analysis of DNA methylation and gene expression data identifies EPAS1 as a key regulator of COPD.

PubMed

Yoo, Seungyeul; Takikawa, Sachiko; Geraghty, Patrick; Argmann, Carmen; Campbell, Joshua; Lin, Luan; Huang, Tao; Tu, Zhidong; Foronjy, Robert F; Feronjy, Robert; Spira, Avrum; Schadt, Eric E; Powell, Charles A; Zhu, Jun

2015-01-01

Chronic Obstructive Pulmonary Disease (COPD) is a complex disease. Genetic, epigenetic, and environmental factors are known to contribute to COPD risk and disease progression. Therefore we developed a systematic approach to identify key regulators of COPD that integrates genome-wide DNA methylation, gene expression, and phenotype data in lung tissue from COPD and control samples. Our integrative analysis identified 126 key regulators of COPD. We identified EPAS1 as the only key regulator whose downstream genes significantly overlapped with multiple genes sets associated with COPD disease severity. EPAS1 is distinct in comparison with other key regulators in terms of methylation profile and downstream target genes. Genes predicted to be regulated by EPAS1 were enriched for biological processes including signaling, cell communications, and system development. We confirmed that EPAS1 protein levels are lower in human COPD lung tissue compared to non-disease controls and that Epas1 gene expression is reduced in mice chronically exposed to cigarette smoke. As EPAS1 downstream genes were significantly enriched for hypoxia responsive genes in endothelial cells, we tested EPAS1 function in human endothelial cells. EPAS1 knockdown by siRNA in endothelial cells impacted genes that significantly overlapped with EPAS1 downstream genes in lung tissue including hypoxia responsive genes, and genes associated with emphysema severity. Our first integrative analysis of genome-wide DNA methylation and gene expression profiles illustrates that not only does DNA methylation play a 'causal' role in the molecular pathophysiology of COPD, but it can be leveraged to directly identify novel key mediators of this pathophysiology.

Hemangiopericytoma in a male breast. Report of a case with cytologic, histologic and immunochemical studies.

PubMed

Jiménez-Ayala, M; Díez-Nau, M D; Larrad, A; Ferrer-Vergara, L; Rodriguez-Costa, J; Lacruz, C; Escalona-Zapata, J

1991-01-01

A hemangiopericytoma in a male breast was studied by fine needle aspiration (FNA) biopsy. The FNA smears contained tissue clumps showing knob-like formations of atypical cells, spindle-shaped cells and fragments of capillaries lined by normal endothelial cells. Immunocytochemical study showed a positive reaction for vimentin, but a negative reaction for desmin and keratin. Staining for Factor VIII was positive only in the capillaries and endothelial cells. The cytodiagnosis was "mesenchymal tumor." Histopathologic study of the mastectomy specimen made the final diagnosis of hemangiopericytoma. While FNA cytology and immunocytochemistry cannot make a definitive diagnosis of this rare vascular tumor, they can be decisive in planning the surgical treatment, as in the present case.

Surgical option for the correction of Peyronie's disease: an autologous tissue-engineered endothelialized graft.

PubMed

Imbeault, Annie; Bernard, Geneviève; Ouellet, Gabrielle; Bouhout, Sara; Carrier, Serge; Bolduc, Stéphane

2011-11-01

Surgical treatment is indicated in severe cases of Peyronie's disease. Incision of the plaque with subsequent graft material implantation is the option of choice. Ideal graft tissue is not yet available. To evaluate the use of an autologous tissue-engineered endothelialized graft by the self-assembly method, for tunica albuginea (TA) reconstruction in Peyronie's disease. Two TA models were created. Human fibroblasts were isolated from a skin biopsy and cultured in vitro until formation of fibroblast sheets. After 4 weeks of maturation, human umbilical vein endothelial cells (HUVEC) were seeded on fibroblasts sheets and wrapped around a tubular support to form a cylinder of about 10 layers. After 21 days of tube maturation, HUVEC were seeded into the lumen of the fibroblast tubes for the endothelialized tunica albuginea (ETA). No HUVEC were seeded into the lumen for the TA model. Both constructs were placed under perfusion in a bioreactor for 1 week. Histology, immunohistochemistry, and burst pressure were performed to characterize mature tubular graft. Animal manipulations were also performed to demonstrate the impact of endothelial cells in vivo. Histology showed uniform multilayered fibroblasts. Extracellular matrix, produced entirely by fibroblasts, presented a good staining for collagen 1. Some elastin fibers were also present. For the TA model, anti-human von Willebrand antibody revealed the endothelial cells forming capillary-like structures. TA model reached a burst pressure of 584 mm Hg and ETA model obtained a burst pressure of 719 mm Hg. This tissue-engineered endothelialized tubular graft is structurally similar to normal TA and presents an adequate mechanical resistance. The self-assembly method used and the autologous property of this model could represent an advantage comparatively to other available grafts. Further evaluation including functional testing will be necessary to characterize in vivo implantation and behavior of the graft. © 2011 International Society for Sexual Medicine.

Unraveling the role of hypoxia-inducible factor (HIF)-1α and HIF-2α in the adaption process of human microvascular endothelial cells (HMEC-1) to hypoxia: Redundant HIF-dependent regulation of macrophage migration inhibitory factor.

PubMed

Hahne, Martin; Schumann, Peggy; Mursell, Mathias; Strehl, Cindy; Hoff, Paula; Buttgereit, Frank; Gaber, Timo

2018-03-01

Hypoxia driven angiogenesis is a prominent feature of tissue regeneration, inflammation and tumor growth and is regulated by hypoxia-inducible factor (HIF)-1 and -2. The distinct functions of HIFs in the hypoxia-induced angiogenesis and metabolic switch of endothelial cells are still unknown and therefore aim of this study. We investigated the role of HIF-1 and -2 in the adaptation of immortalized human microvascular endothelial cells (HMEC-1) to hypoxic conditions (1% O 2 ) in terms of angiogenesis, cytokine secretion, gene expression and ATP/ADP-ratio using shRNA-mediated reduction of the oxygen sensitive α-subunits of either HIF-1 or HIF-2 or the combination of both. Reduction of HIF-1α diminished cellular energy, hypoxia-induced glycolytic gene expression, and angiogenesis not altering pro-angiogenic factors. Reduction of HIF-2α diminished hypoxia-induced pro-angiogenic factors, enhanced anti-angiogenic factors and attenuated angiogenesis not altering glycolytic gene expression. Reduction of both HIFs reduced cell survival, gene expression of glycolytic enzymes and pro-angiogenic factors as compared to the corresponding control. Finally, we identified the macrophage migration inhibitory factor (MIF) to be redundantly regulated by HIF-1 and HIF-2 and to be essential in the process of hypoxia-driven angiogenesis. Our results demonstrate a major impact of HIF-1 and HIF-2 on hypoxia-induced angiogenesis indicating distinct but also overlapping functions of HIF-1 and HIF-2. These findings open new possibilities for therapeutic approaches by specifically targeting the HIF-1 and HIF-2 or their target MIF. Copyright © 2017 Elsevier Inc. All rights reserved.

Inhibition of HMGCoA reductase by simvastatin protects mice from injurious mechanical ventilation.

PubMed

Manitsopoulos, Nikolaos; Orfanos, Stylianos E; Kotanidou, Anastasia; Nikitopoulou, Ioanna; Siempos, Ilias; Magkou, Christina; Dimopoulou, Ioanna; Zakynthinos, Spyros G; Armaganidis, Apostolos; Maniatis, Nikolaos A

2015-02-14

Mortality from severe acute respiratory distress syndrome exceeds 40% and there is no available pharmacologic treatment. Mechanical ventilation contributes to lung dysfunction and mortality by causing ventilator-induced lung injury. We explored the utility of simvastatin in a mouse model of severe ventilator-induced lung injury. Male C57BL6 mice (n = 7/group) were pretreated with simvastatin or saline and received protective (8 mL/kg) or injurious (25 mL/kg) ventilation for four hours. Three doses of simvastatin (20 mg/kg) or saline were injected intraperitoneally on days -2, -1 and 0 of the experiment. Lung mechanics, (respiratory system elastance, tissue damping and airway resistance), were evaluated by forced oscillation technique, while respiratory system compliance was measured with quasi-static pressure-volume curves. A pathologist blinded to treatment allocation scored hematoxylin-eosin-stained lung sections for the presence of lung injury. Pulmonary endothelial dysfunction was ascertained by bronchoalveolar lavage protein content and lung tissue expression of endothelial junctional protein Vascular Endothelial cadherin by immunoblotting. To assess the inflammatory response in the lung, we determined bronchoalveolar lavage fluid total cell content and neutrophil fraction by microscopy and staining in addition to Matrix-Metalloprotease-9 by ELISA. For the systemic response, we obtained plasma levels of Tumor Necrosis Factor-α, Interleukin-6 and Matrix-Metalloprotease-9 by ELISA. Statistical hypothesis testing was undertaken using one-way analysis of variance and Tukey's post hoc tests. Ventilation with high tidal volume (HVt) resulted in significantly increased lung elastance by 3-fold and decreased lung compliance by 45% compared to low tidal volume (LVt) but simvastatin abrogated lung mechanical alterations of HVt. Histologic lung injury score increased four-fold by HVt but not in simvastatin-pretreated mice. Lavage pleocytosis and neutrophilia were induced by HVt but were significantly attenuated by simvastatin. Microvascular protein permeability increase 20-fold by injurious ventilation but only 4-fold with simvastatin. There was a 3-fold increase in plasma Tumor Necrosis Factor-α, a 7-fold increase in plasma Interleukin-6 and a 20-fold increase in lavage fluid Matrix-Metalloprotease-9 by HVt but simvastatin reduced these levels to control. Lung tissue vascular endothelial cadherin expression was significantly reduced by injurious ventilation but remained preserved by simvastatin. High-dose simvastatin prevents experimental hyperinflation lung injury by angioprotective and anti-inflammatory effects.

Identification of candidate angiogenic inhibitors processed by matrix metalloproteinase 2 (MMP-2) in cell-based proteomic screens: disruption of vascular endothelial growth factor (VEGF)/heparin affin regulatory peptide (pleiotrophin) and VEGF/Connective tissue growth factor angiogenic inhibitory complexes by MMP-2 proteolysis.

PubMed

Dean, Richard A; Butler, Georgina S; Hamma-Kourbali, Yamina; Delbé, Jean; Brigstock, David R; Courty, José; Overall, Christopher M

2007-12-01

Matrix metalloproteinases (MMPs) exert both pro- and antiangiogenic functions by the release of cytokines or proteolytically generated angiogenic inhibitors from extracellular matrix and basement membrane remodeling. In the Mmp2-/- mouse neovascularization is greatly reduced, but the mechanistic aspects of this remain unclear. Using isotope-coded affinity tag labeling of proteins analyzed by multidimensional liquid chromatography and tandem mass spectrometry we explored proteome differences between Mmp2-/- cells and those rescued by MMP-2 transfection. Proteome signatures that are hallmarks of proteolysis revealed cleavage of many known MMP-2 substrates in the cellular context. Proteomic evidence of MMP-2 processing of novel substrates was found. Insulin-like growth factor binding protein 6, follistatin-like 1, and cystatin C protein cleavage by MMP-2 was biochemically confirmed, and the cleavage sites in heparin affin regulatory peptide (HARP; pleiotrophin) and connective tissue growth factor (CTGF) were sequenced by matrix-assisted laser desorption ionization-time of flight mass spectrometry. MMP-2 processing of HARP and CTGF released vascular endothelial growth factor (VEGF) from angiogenic inhibitory complexes. The cleaved HARP N-terminal domain increased HARP-induced cell proliferation, whereas the HARP C-terminal domain was antagonistic and decreased cell proliferation and migration. Hence the unmasking of cytokines, such as VEGF, by metalloproteinase processing of their binding proteins is a new mechanism in the control of cytokine activation and angiogenesis.

Identification of Candidate Angiogenic Inhibitors Processed by Matrix Metalloproteinase 2 (MMP-2) in Cell-Based Proteomic Screens: Disruption of Vascular Endothelial Growth Factor (VEGF)/Heparin Affin Regulatory Peptide (Pleiotrophin) and VEGF/Connective Tissue Growth Factor Angiogenic Inhibitory Complexes by MMP-2 Proteolysis▿ †

PubMed Central

Dean, Richard A.; Butler, Georgina S.; Hamma-Kourbali, Yamina; Delbé, Jean; Brigstock, David R.; Courty, José; Overall, Christopher M.

2007-01-01

Matrix metalloproteinases (MMPs) exert both pro- and antiangiogenic functions by the release of cytokines or proteolytically generated angiogenic inhibitors from extracellular matrix and basement membrane remodeling. In the Mmp2−/− mouse neovascularization is greatly reduced, but the mechanistic aspects of this remain unclear. Using isotope-coded affinity tag labeling of proteins analyzed by multidimensional liquid chromatography and tandem mass spectrometry we explored proteome differences between Mmp2−/− cells and those rescued by MMP-2 transfection. Proteome signatures that are hallmarks of proteolysis revealed cleavage of many known MMP-2 substrates in the cellular context. Proteomic evidence of MMP-2 processing of novel substrates was found. Insulin-like growth factor binding protein 6, follistatin-like 1, and cystatin C protein cleavage by MMP-2 was biochemically confirmed, and the cleavage sites in heparin affin regulatory peptide (HARP; pleiotrophin) and connective tissue growth factor (CTGF) were sequenced by matrix-assisted laser desorption ionization-time of flight mass spectrometry. MMP-2 processing of HARP and CTGF released vascular endothelial growth factor (VEGF) from angiogenic inhibitory complexes. The cleaved HARP N-terminal domain increased HARP-induced cell proliferation, whereas the HARP C-terminal domain was antagonistic and decreased cell proliferation and migration. Hence the unmasking of cytokines, such as VEGF, by metalloproteinase processing of their binding proteins is a new mechanism in the control of cytokine activation and angiogenesis. PMID:17908800

Combined effect of substance P and curcumin on cutaneous wound healing in diabetic rats.

PubMed

Kant, Vinay; Kumar, Dinesh; Prasad, Raju; Gopal, Anu; Pathak, Nitya N; Kumar, Pawan; Tandan, Surender K

2017-05-15

Our earlier studies demonstrated that topically applied substance P (SP) or curcumin on excision skin wound accelerated the wound healing in streptozotocin-induced diabetic rats. In the present study, we aimed to evaluate the wound healing potential of combination of SP and curcumin in diabetic rats. Open cutaneous excision wound was created on the back of each of the 60 diabetic rats. Wound-inflicted rats were equally divided into three groups namely, control, gel treated, and SP + curcumin treated. Normal saline, pluronic gel, and SP (0.5 × 10 -6 M) + curcumin (0.15%) were topically applied once daily for 19 d to these control, gel-treated, and SP + curcumin groups, respectively. SP + curcumin combination significantly accelerated wound closure and decreased messenger RNA expressions of tumor necrosis factor-alpha, interleukin-1beta, and matrix metalloproteinase-9, whereas the combination markedly increased the expressions of interleukin-10, vascular endothelial growth factor, transforming growth factor-beta1, hypoxia-inducible factor 1-alpha, stromal cell-derived factors-1alpha, heme oxygenase-1 and endothelial nitric oxide synthase, and activities of superoxide dismutase, catalase, and glutathione peroxidase in granulation-healing tissue, compared with control and gel-treated groups. In combination group, granulation tissue was better, as was evidenced by improved fibroblast proliferation, collagen deposition, microvessel density, growth-associated protein 43-positive nerve fibers, and thick regenerated epithelial layer. The combination of SP and curcumin accelerated wound healing in diabetic rats and both the drugs were compatible at the doses used in this study. Copyright © 2017 Elsevier Inc. All rights reserved.

Glutathione adducts on sarcoplasmic/endoplasmic reticulum Ca2+ ATPase Cys-674 regulate endothelial cell calcium stores and angiogenic function as well as promote ischemic blood flow recovery.

PubMed

Thompson, Melissa D; Mei, Yu; Weisbrod, Robert M; Silver, Marcy; Shukla, Praphulla C; Bolotina, Victoria M; Cohen, Richard A; Tong, Xiaoyong

2014-07-18

The sarco/endoplasmic reticulum Ca(2+) ATPase (SERCA) is key to Ca(2+) homeostasis and is redox-regulated by reversible glutathione (GSH) adducts on the cysteine (C) 674 thiol that stimulate Ca(2+) uptake activity and endothelial cell angiogenic responses in vitro. We found that mouse hind limb muscle ischemia induced S-glutathione adducts on SERCA in both whole muscle tissue and endothelial cells. To determine the role of S-glutathiolation, we used a SERCA 2 C674S heterozygote knock-in (SKI) mouse lacking half the key thiol. Following hind limb ischemia, SKI animals had decreased SERCA S-glutathione adducts and impaired blood flow recovery. We studied SKI microvascular endothelial cells in which total SERCA 2 expression was unchanged. Cultured SKI microvascular endothelial cells showed impaired migration and network formation compared with wild type (WT). Ca(2+) studies showed decreased nitric oxide (·NO)-induced (45)Ca(2+) uptake into the endoplasmic reticulum (ER) of SKI cells, while Fura-2 studies revealed lower Ca(2+) stores and decreased vascular endothelial growth factor (VEGF)- and ·NO-induced Ca(2+) influx. Adenoviral overexpression of calreticulin, an ER Ca(2+) binding protein, increased ionomycin-releasable stores, VEGF-induced Ca(2+) influx and endothelial cell migration. Taken together, these data indicate that the redox-sensitive Cys-674 thiol on SERCA 2 is required for normal endothelial cell Ca(2+) homeostasis and ischemia-induced angiogenic responses, revealing a novel redox control of angiogenesis via Ca(2+) stores. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Platelet activation by Histophilus somni and its lipooligosaccharide induces endothelial cell proinflammatory responses and platelet internalization.

PubMed

Kuckleburg, Christopher J; McClenahan, Dave J; Czuprynski, Charles J

2008-02-01

Histophilus somni is a gram-negative coccobacillus that causes respiratory and reproductive disease in cattle. The hallmark of systemic H. somni infection is diffuse vascular inflammation that can lead to an acute central nervous system disease known as thrombotic meningoencephalitis. Previously, we demonstrated that H. somni and its lipooligosaccharide (LOS) activate bovine platelets, leading to expression of P selectin, CD40L, and FasL. Because activated platelets have been reported to induce endothelial cell cytokine production and adhesion molecule expression, we sought to determine if bovine platelets induce proinflammatory and procoagulative changes in bovine pulmonary artery endothelial cells. Endothelial cells were incubated with platelets activated with adenosine diphosphate, H. somni, or H. somni LOS. Incubation with activated bovine platelets significantly increased expression of in adhesion molecules (intercellular adhesion molecule 1, E selectin) and tissue factor, as measured by flow cytometry, real-time polymerase chain reaction, and Western blot analysis. Activated platelets also up-regulated expression of endothelial cell IL-1beta, monocyte chemoattractant protein 1, and macrophage inflammatory protein 1alpha as determined by real-time polymerase chain reaction and an IL-1beta enzyme-linked immunosorbent assay. An interesting and surprising finding was that bovine platelets activated by H. somni or its LOS were internalized by bovine endothelial cells as visualized by transmission electron microscopy. This internalization seemed to correlate with endothelial cell activation and morphological changes indicative of cell stress. These findings suggest that activated platelets might play a role in promoting vascular inflammation during H. somni infection.

Functional Definition of Progenitors Versus Mature Endothelial Cells Reveals Key SoxF-Dependent Differentiation Process.

PubMed

Patel, Jatin; Seppanen, Elke J; Rodero, Mathieu P; Wong, Ho Yi; Donovan, Prudence; Neufeld, Zoltan; Fisk, Nicholas M; Francois, Mathias; Khosrotehrani, Kiarash

2017-02-21

During adult life, blood vessel formation is thought to occur via angiogenic processes involving branching from existing vessels. An alternate proposal suggests that neovessels form from endothelial progenitors able to assemble the intimal layers. We here aimed to define vessel-resident endothelial progenitors in vivo in a variety of tissues in physiological and pathological situations such as normal aorta, lungs, and wound healing, tumors, and placenta, as well. Based on protein expression levels of common endothelial markers using flow cytometry, 3 subpopulations of endothelial cells could be identified among VE-Cadherin+ and CD45- cells. Lineage tracing by using Cdh5cre ERt2 /Rosa-YFP reporter strategy demonstrated that the CD31-/loVEGFR2lo/intracellular endothelial population was indeed an endovascular progenitor (EVP) of an intermediate CD31intVEGFR2lo/intracellular transit amplifying (TA) and a definitive differentiated (D) CD31hiVEGFR2hi/extracellular population. EVP cells arose from vascular-resident beds that could not be transferred by bone marrow transplantation. Furthermore, EVP displayed progenitor-like status with a high proportion of cells in a quiescent cell cycle phase as assessed in wounds, tumors, and aorta. Only EVP cells and not TA and D cells had self-renewal capacity as demonstrated by colony-forming capacity in limiting dilution and by transplantation in Matrigel plugs in recipient mice. RNA sequencing revealed prominent gene expression differences between EVP and D cells. In particular, EVP cells highly expressed genes related to progenitor function including Sox9 , Il33 , Egfr , and Pdfgrα. Conversely, D cells highly expressed genes related to differentiated endothelium including Ets1&2 , Gata2 , Cd31 , Vwf , and Notch . The RNA sequencing also pointed to an essential role of the Sox18 transcription factor. The role of SOX18 in the differentiation process was validated by using lineage-tracing experiments based on S ox18Cre ERt2 /Rosa-YFP mice. Besides, in the absence of functional SOX18/SOXF, EVP progenitors were still present, but TA and D populations were significantly reduced. Our findings support an entirely novel endothelial hierarchy, from EVP to TA to D, as defined by self-renewal, differentiation, and molecular profiling of an endothelial progenitor. This paradigm shift in our understanding of vascular-resident endothelial progenitors in tissue regeneration opens new avenues for better understanding of cardiovascular biology. © 2016 American Heart Association, Inc.

Angiogenesis in the female reproductive organs: pathological implications

PubMed Central

Reynolds, Lawrence P; Grazul-Bilska, Anna T; Redmer, Dale A

2002-01-01

The female reproductive organs (ovary, uterus, and placenta) are some of the few adult tissues that exhibit regular intervals of rapid growth. They also are highly vascular and have high rates of blood flow. Angiogenesis, or vascular growth, is therefore an important component of the growth and function of these tissues. As with many other tissues, vascular endothelial growth factors (VEGFs) and fibroblast growth factors (FGFs) appear to be major angiogenic factors in the female reproductive organs. A variety of pathologies of the female reproductive organs are associated with disturbances of the angiogenic process, including dysfunctional uterine bleeding, endometrial hyperplasia and carcinoma, endometriosis, failed implantation and subnormal foetal growth, myometrial fibroids (uterine leiomyomas) and adenomyosis, ovarian hyperstimulation syndrome, ovarian carcinoma, and polycystic ovary syndrome. These pathologies are also associated with altered expression of VEGFs and/or FGFs. In the near future, angiogenic or antiangiogenic compounds may prove to be effective therapeutic agents for treating these pathologies. In addition, monitoring of angiogenesis or angiogenic factor expression may provide a means of assessing the efficacy of these therapies. PMID:12485460

Mitochondria-targeted antioxidant SkQ1 improves impaired dermal wound healing in old mice.

PubMed

Demyanenko, Ilya A; Popova, Ekaterina N; Zakharova, Vlada V; Ilyinskaya, Olga P; Vasilieva, Tamara V; Romashchenko, Valeria P; Fedorov, Artem V; Manskikh, Vasily N; Skulachev, Maxim V; Zinovkin, Roman A; Pletjushkina, Olga Yu; Skulachev, Vladimir P; Chernyak, Boris V

2015-07-01

The process of skin wound healing is delayed or impaired in aging animals. To investigate the possible role of mitochondrial reactive oxygen species (mtROS) in cutaneous wound healing of aged mice, we have applied the mitochondria-targeted antioxidant SkQ1. The SkQ1 treatment resulted in accelerated resolution of the inflammatory phase, formation of granulation tissue, vascularization and epithelization of the wounds. The wounds of SkQ1-treated mice contained increased amount of myofibroblasts which produce extracellular matrix proteins and growth factors mediating granulation tissue formation. This effect resembled SkQ1-induced differentiation of fibroblasts to myofibroblast, observed earlierin vitro. The Transforming Growth Factor beta (TGFb) produced by SkQ1-treated fibroblasts was found to stimulated motility of endothelial cells in vitro, an effect which may underlie pro-angiogenic action of SkQ1 in the wounds. In vitro experiments showed that SkQ1 prevented decomposition of VE-cadherin containing contacts and following increase in permeability of endothelial cells monolayer, induced by pro-inflammatory cytokine TNF. Prevention of excessive reaction of endothelium to the pro-inflammatory cytokine(s) might account for anti-inflammatory effect of SkQ1. Our findings point to an important role of mtROS in pathogenesis of age-related chronic wounds.

Mitochondria-targeted antioxidant SkQ1 improves impaired dermal wound healing in old mice

PubMed Central

Zakharova, Vlada V.; Ilyinskaya, Olga P.; Vasilieva, Tamara V.; Romashchenko, Valeria P.; Fedorov, Artem V.; Manskikh, Vasily N.; Skulachev, Maxim V.; Zinovkin, Roman A.; Pletjushkina, Olga Yu.; Skulachev, Vladimir P.; Chernyak, Boris V.

2015-01-01

The process of skin wound healing is delayed or impaired in aging animals. To investigate the possible role of mitochondrial reactive oxygen species (mtROS) in cutaneous wound healing of aged mice, we have applied the mitochondria-targeted antioxidant SkQ1. The SkQ1 treatment resulted in accelerated resolution of the inflammatory phase, formation of granulation tissue, vascularization and epithelization of the wounds. The wounds of SkQ1-treated mice contained increased amount of myofibroblasts which produce extracellular matrix proteins and growth factors mediating granulation tissue formation. This effect resembled SkQ1-induced differentiation of fibroblasts to myofibroblast, observed earlier in vitro. The Transforming Growth Factor beta (TGFβ)produced by SkQ1-treated fibroblasts was found to stimulated motility of endothelial cells in vitro, an effect which may underlie pro-angiogenic action of SkQ1 in the wounds. In vitro experiments showed that SkQ1 prevented decomposition of VE-cadherin containing contacts and following increase in permeability of endothelial cells monolayer, induced by pro-inflammatory cytokine TNF. Prevention of excessive reaction of endothelium to the pro-inflammatory cytokine(s) might account for anti-inflammatory effect of SkQ1. Our findings point to an important role of mtROS in pathogenesis of age-related chronic wounds. PMID:26187706

6-Methylsulfinylhexyl isothiocyanate modulates endothelial cell function and suppresses leukocyte adhesion.

PubMed

Okamoto, Takayuki; Akita, Nobuyuki; Nagai, Masashi; Hayashi, Tatsuya; Suzuki, Koji

2014-01-01

6-Methylsulfinylhexyl isothiocyanate (6-MSITC) is an active compound in wasabi (Wasabia japonica Matsum.), which is one of the most popular spices in Japan. 6-MSITC suppresses lipopolysaccharide-induced macrophage activation, arachidonic- or adenosine diphosphate-induced platelet activation, and tumor cell proliferation. These data indicate that 6-MSITC has several biological activities involving anti-inflammatory, anti-coagulant, and anti-apoptosis properties. Endothelial cells (ECs) maintain vascular homeostasis and play crucial roles in crosstalk between blood coagulation and vascular inflammation. In this study, we determined the anti-coagulant and anti-inflammatory effects of 6-MSITC on human umbilical vein endothelial cells (HUVECs). 6-MSITC slightly reduced tissue factor expression, but did not alter von Willebrand factor release in activated HUVECs. 6-MSITC modulated the generation of activated protein C, which is essential for negative regulation of blood coagulation, on normal ECs. In addition, 6-MSITC reduced tumor necrosis factor-α (TNF-α)-induced interleukin-6 and monocyte chemoattractant protein-1 expression. 6-MSITC markedly attenuated TNF-α-induced adhesion of human monoblast U937 cells to HUVECs and reduced vascular cell adhesion molecule-1 and E-selectin mRNA expression in activated ECs. These results showed that 6-MSITC modulates EC function and suppresses cell adhesion. This study provides new insight into the mechanism of the anti-inflammatory effect of 6-MSITC, suggesting that 6-MSITC has therapeutic potential as a treatment for vasculitis and vascular inflammation.

Potential regulatory molecules in the human trabecular meshwork of patients with glaucoma: immunohistochemical profile of a number of inflammatory cytokines.

PubMed

Taurone, Samanta; Ripandelli, Guido; Pacella, Elena; Bianchi, Enrica; Plateroti, Andrea Maria; De Vito, Stefania; Plateroti, Pasquale; Grippaudo, Francesca Romana; Cavallotti, Carlo; Artico, Marco

2015-02-01

Glaucoma occurs when there are imbalances between the production and the drainage of the eye liquid. The vast majority of the aqueous humor leaves the eye through the trabecular meshwork (TM). The cause of hypertonicity may be due to an alteration in the thickness of the TM. In the majority of cases the molecular changes that determine primary open‑angle glaucoma (POAG) are unclear. However, it has been hypothesized that the significant increase in the extracellular matrix (ECM) of the fibrillary bands in the TM is associated with possible inflammatory conditions. In this study the tissue distribution of interleukin (IL)‑6, IL‑1β, transforming growth factor-β1 (TGF‑β1), vascular endothelial growth factor (VEGF) and tumor necrosis factor α (TNF‑α) was analyzed in TM samples from patients with POAG by immunohistochemistry. Seven specimens from patients with POAG and three control tissues were analyzed by immunohistochemistry using specific antibodies against these cytokines. Morphological changes in the TM, such as increased cell content, macrophages, fibrosis and accumulation of neutrophils, were observed by transmission electron microscopy. In human TM tissues, an evident immunoreactivity for IL‑6, IL‑1β and TNF‑α was observed in patients with POAG when compared with the control subjects, indicating that these cytokines may be correlated with disease activity. TM endothelial cells secrete a number of factors and cytokines that modulate the functions of the cells and the ECM of the conventional outflow pathway. In the TM in glaucoma, macrophages produce cytokines, including IL‑6, IL‑1β and TNF‑α, leading to an acute inflammatory response and recruitment of other immune cells, including T lymphocytes. In addition, TGF‑β1 regulates and induces the expression of IL‑6 in TM that indirectly induces angiogenesis by stimulating VEGF expression. The present results support previous evidence that suggests that growth factors and cytokines can induce ECM remodelling and alter cytoskeletal interactions in the TM.

Endothelial function is associated with myocardial diastolic function in women with systemic lupus erythematosus.

PubMed

Chin, Calvin W L; Chin, Chee-Yang; Ng, Marie X R; Le, Thu-Thao; Huang, Fei-Qiong; Fong, Kok-Yong; Thumboo, Julian; Tan, Ru-San

2014-09-01

Endothelial dysfunction is associated with traditional and systemic lupus erythematosus (SLE)-specific risk factors, and early data suggest reversibility of endothelial dysfunction with therapy. The clinical relevance of endothelial function assessment has been limited by the lack of studies, demonstrating its prognostic significance and impact on early myocardial function. Therefore, we aimed to determine the association between endothelial and myocardial diastolic function in SLE women. Women with SLE and no coronary artery disease were prospectively recruited and underwent radionuclide myocardial perfusion imaging (MPI) (Jetstream, Philips, the Netherlands) to exclude subclinical myocardial ischemia. Cardiac and vascular functions were assessed in all patients (Alpha 10, Aloka, Tokyo). Diastolic function was assessed using pulse wave early (E) and late mitral blood inflow and myocardial tissue Doppler (mean of medial and lateral annulus e') velocities. Endothelial function was measured using brachial artery flow-mediated vasodilatation (FMD%). Univariate and multivariate linear regressions were used to assess the association between FMD% and myocardial diastolic function, adjusting for potential confounders. Thirty-eight patients without detectable myocardial ischemia on MPI were studied (mean age 44 ± 10 years; mean disease duration 14 ± 6 years). About 61 % of patients had normal diastolic function (E/e' ≤ 8), and 5 % of patients had definite diastolic dysfunction with E/e' > 13 (mean 7.1 ± 2.9). FMD% was associated with E/e' (regression coefficient β = -0.35; 95 % CI -0.62 to -0.08; p = 0.01) independent of systolic blood pressure, age, and SLICC/ACR Damage Index.

Exercise training improves endothelial function in resistance arteries of young prehypertensives.

PubMed

Beck, D T; Martin, J S; Casey, D P; Braith, R W

2014-05-01

Prehypertension is associated with reduced conduit artery endothelial function and perturbation of oxidant/antioxidant status. It is unknown whether endothelial dysfunction persists to resistance arteries and whether exercise training affects oxidant/antioxidant balance in young prehypertensives. We examined resistance artery function using venous occlusion plethysmography measurement of forearm (FBF) and calf blood flow (CBF) at rest and during reactive hyperaemia (RH), as well as lipid peroxidation (8-iso-PGF2α) and antioxidant capacity (Trolox-equivalent antioxidant capacity; TEAC) before and after exercise intervention or time control. Forty-three unmedicated prehypertensive and 15 matched normotensive time controls met screening requirements and participated in the study (age: 21.1±0.8 years). Prehypertensive subjects were randomly assigned to resistance exercise training (PHRT; n=15), endurance exercise training (PHET; n=13) or time-control groups (PHTC; n=15). Treatment groups exercised 3 days per week for 8 weeks. Peak and total FBF were lower in prehypertensives than normotensives (12.7±1.2 ml min(-1) per100 ml tissue and 89.1±7.7 ml min(-1) per 100 ml tissue vs 16.3±1.0 ml min(-1) per 100 ml tissue and 123.3±6.4 ml min(-1) per 100 ml tissue, respectively; P<0.05). Peak and total CBF were lower in prehypertensives than normotensives (15.3±1.2 ml min(-1) per 100 ml tissue and 74±8.3 ml min(-1) per 100 ml tissue vs 20.9±1.4 ml min(-1) per 100 ml tissue and 107±9.2 ml min(-1) per 100 ml tissue, respectively; P<0.05). PHRT and PHET improved humoral measures of TEAC (+24 and +30%) and 8-iso-PGF2α (-43 and -40%, respectively; P < or = 0.05). This study provides evidence that young prehypertensives exhibit reduced resistance artery endothelial function and that short-term (8 weeks) resistance or endurance training are effective in improving resistance artery endothelial function and oxidant/antioxidant balance in young prehypertensives.

Hepatocyte Growth Factor Inhibits Apoptosis by the Profibrotic Factor Angiotensin II via Extracellular Signal-regulated Kinase 1/2 in Endothelial Cells and Tissue Explants

DTIC Science & Technology

2010-12-01

were subjected to SDS- polyacryl - amide gel electrophoresis and electroblotted onto nitrocellulose membrane. Membranes were blocked with 5% bovine...1 mM sodium fluoride, 0.1 mM sodium orthovanadate, 1 mM tetrasodium pyrophosphate, 2 mM phenylmethylsulfonyl fluoride, 10 g/ml leupeptin, and 10 g...buffer [50 mM Tris-HCl, 1 mM EGTA, 1% (wt/vol) CHAPS, 10% glycerol, 50 mM sodium fluoride, 1 mM sodium orthovanadate, 2 mM phenylmethylsulfonyl fluoride

Purification of Growth Factor mRNA in Renal Tissues:bFGF-2, FGF-2, TGFα, and EGFR.

PubMed

Mydlo, J H

2001-01-01

Growth factors are polypeptides that induce cell mitogenicity, and thus play an important role in the etiology and progression of tumors (1). Fibroblast growth factors (FGF) constitute a family of structurally related polypeptides of 146 amino acids, which exhibit a wide spectrum of biologic activities, including angiogenesis or the formation of a vascular network. FGFs are mitogenic towards many mesodermal and ectodermal cell types, and can also induce and/or inhibit differentiation of cells (2). These heparin-binding factors are categorized as FGF-1 through FGF-10. Acidic FGF, or FGF-1, is found mostly in brain and other neural tissues. Basic FGF, or FGF- 2, a protein of 18 kDa mw, is one of the most ubiqitous growth factors. It is found in numerous benign and cancerous human and animal tissues, including kidney, prostate, and bladder (3-6). In some cases it has also been demonstrated to have potential as a tumor marker (7-11). One group reported greater recovery of both FGF-2 protein and FGF-2 mRNA from renal-cancer tissue compared to equal amounts of normal renal tissue (5). Furthermore, when purified FGF-2 from renal cell carcinoma (RCC) is added exogenously to other established renal tumorcell lines and endothelial cell lines, it demonstrates significant mitogenic activity (6). Thus, renal tumors may use FGF-2 in an autocrine manner to sustain themselves.

The oncogenic gene fusion TMPRSS2: ERG is not a diagnostic or prognostic marker for ovarian cancer

PubMed Central

Huang, Lillian; Schauer, Isaiah G; Zhang, Jing; Mercado-Uribe, Imelda; Deavers, Michael T; Huang, Jiaoti; Liu, Jinsong

2011-01-01

TMPRSS2:ERG is a gene fusion resulting from the chromosomal rearrangement of the androgen-regulated TMPRSS2 gene and the ETS transcription factor ERG, leading to the over-expression of the oncogenic molecule ERG. This gene rearrangement has been found in approximately half of all prostate cancers and ERG overexpression is considered as a novel diagnostic marker for prostate carcinoma. However, little is known about the role of the TMPRSS2:ERG gene fusion in ovarian cancer. The purpose of this study was to test ERG expression in ovarian cancer and its potential as a diagnostic marker for ovarian carcinoma progression. A tissue microarray containing 180 ovarian cancer tissues of various pathological types and grades were examined by immunohistochemical analysis for expression of ERG. We also used 40 prostate carcinoma tissues and 40 normal tissues for comparison in parallel experiments. ERG-positive expression was detected in 40% of the prostate tumor cancer, as well as in internal positive control endothelial cells, confirming over-expression of ERG in prostate cancer at relatively the same rate observed by others. In contrast, all of the ovarian tumor patient tissues of varying histologic types were ERG-negative, despite some positivity in endothelial cells. These results suggest that the oncogenic gene fusion TMPRSS2:ERG does not occur in ovarian cancer relative to prostate cancer. Therefore, development of ERG expression profile would not be a useful diagnostic or prognostic marker for ovarian cancer patient screening. PMID:22076164

The oncogenic gene fusion TMPRSS2: ERG is not a diagnostic or prognostic marker for ovarian cancer.

PubMed

Huang, Lillian; Schauer, Isaiah G; Zhang, Jing; Mercado-Uribe, Imelda; Deavers, Michael T; Huang, Jiaoti; Liu, Jinsong

2011-01-01

TMPRSS2:ERG is a gene fusion resulting from the chromosomal rearrangement of the androgen-regulated TMPRSS2 gene and the ETS transcription factor ERG, leading to the over-expression of the oncogenic molecule ERG. This gene rearrangement has been found in approximately half of all prostate cancers and ERG overexpression is considered as a novel diagnostic marker for prostate carcinoma. However, little is known about the role of the TMPRSS2:ERG gene fusion in ovarian cancer. The purpose of this study was to test ERG expression in ovarian cancer and its potential as a diagnostic marker for ovarian carcinoma progression. A tissue microarray containing 180 ovarian cancer tissues of various pathological types and grades were examined by immunohistochemical analysis for expression of ERG. We also used 40 prostate carcinoma tissues and 40 normal tissues for comparison in parallel experiments. ERG-positive expression was detected in 40% of the prostate tumor cancer, as well as in internal positive control endothelial cells, confirming over-expression of ERG in prostate cancer at relatively the same rate observed by others. In contrast, all of the ovarian tumor patient tissues of varying histologic types were ERG-negative, despite some positivity in endothelial cells. These results suggest that the oncogenic gene fusion TMPRSS2:ERG does not occur in ovarian cancer relative to prostate cancer. Therefore, development of ERG expression profile would not be a useful diagnostic or prognostic marker for ovarian cancer patient screening.

Heparin-Based Coacervate of FGF2 Improves Dermal Regeneration by Asserting a Synergistic Role with Cell Proliferation and Endogenous Facilitated VEGF for Cutaneous Wound Healing.

PubMed

Wu, Jiang; Ye, Jingjing; Zhu, Jingjing; Xiao, Zecong; He, Chaochao; Shi, Hongxue; Wang, Yadong; Lin, Cai; Zhang, Hongyu; Zhao, Yingzheng; Fu, Xiaobing; Chen, Hong; Li, Xiaokun; Li, Lin; Zheng, Jie; Xiao, Jian

2016-06-13

Effective wound healing requires complicated, coordinated interactions and responses at protein, cellular, and tissue levels involving growth factor expression, cell proliferation, wound closure, granulation tissue formation, and vascularization. In this study, we develop a heparin-based coacervate consisting of poly(ethylene argininylaspartate digylceride) (PEAD) as a storage matrix, heparin as a bridge, and fibroblast growth factor-2 (FGF2) as a cargo (namely heparin-FGF2@PEAD) for wound healing. First, in vitro characterization demonstrates the loading efficiency and control release of FGF2 from the heparin-FGF2@PEAD coacervate. The following in vivo studies examine the wound healing efficiency of the heparin-FGF2@PEAD coacervate upon delivering FGF2 to full-thickness excisional skin wounds in vivo, in comparison with the other three control groups with saline, heparin@PEAD as vehicle, and free FGF2. Collective in vivo data show that controlled release of FGF2 to the wounds by the coacervate significantly accelerates the wound healing by promoting cell proliferation, stimulating the secretion of vascular endothelial growth factor (VEGF) for re-epithelization, collagen deposition, and granulation tissue formation, and enhancing the expression of platelet endothelial cell adhesion molecule (CD31) and alpha-smooth muscle actin (α-SMA) for blood vessel maturation. In parallel, no obvious wound healing effect is found for the control, vehicle, and free FGF2 groups, indicating the important role of the coavervate in the wound healing process. This work designs a suitable delivery system that can protect and release FGF2 in a sustained and controlled manner, which provides a promising therapeutic potential for topical treatment of wounds.

Increased expression of placental growth factor in high-grade endometrial carcinoma

PubMed Central

COENEGRACHTS, LIEVE; SCHRAUWEN, STEFANIE; VAN BREE, RITA; DESPIERRE, EVELYN; LUYTEN, CATHERINE; JONCKX, BART; STASSEN, JEAN MARIE; VERGOTE, IGNACE; AMANT, FRÉDÉRIC

2013-01-01

Placental growth factor (PlGF), a homolog of vascular endothelial growth factor (VEGF), exerts pleiotropic functions in cancer by affecting tumor cells as well as endothelial and inflammatory cells. Moreover, PlGF expression correlates with tumor stage, recurrence, metastasis and patient outcome in different types of cancer. Recently, administration of anti-PlGF therapy reduced tumor growth and metastasis in preclinical tumor models. In the present study, we evaluated the diagnostic and prognostic value of systemic and local expression of PlGF in primary endometrial carcinomas. PlGF levels in tumor lysates (n=128) and serum (n=88) of patients with primary endometrial cancer were determined using ELISA. PlGF mRNA expression in endometrial carcinoma tissues was quantified by quantitative qRT-PCR. Results were compared to endometrial cancer stage and grade. Systemic PlGF levels were not altered in patients with endometrial cancer (FIGO stage I-II-III) as compared to healthy controls. Only in FIGO stage IV patients, serum PlGF levels were slightly increased. Local PlGF mRNA and protein expression in endometrial tumors progressively increased with tumor grade. In endometrioid carcinomas, PlGF mRNA expression was significantly increased in endometrioid grade 3 tumors as compared to normal endometrial tissue. PlGF protein expression was significantly increased in endometrioid grade 2 and 3 carcinomas and in serous carcinomas as compared to normal endometrial tissue. Our study showed that systemic/serum PlGF levels cannot be used as a diagnostic or prognostic marker in endometrial cancer. However, the increased local expression of PlGF, primarily in high-grade carcinomas, underscores the possibility for preclinical assessment of anti-PlGF therapy in endometrial cancer. PMID:23232836

Increased expression of placental growth factor in high-grade endometrial carcinoma.

PubMed

Coenegrachts, Lieve; Schrauwen, Stefanie; Van Bree, Rita; Despierre, Evelyn; Luyten, Catherine; Jonckx, Bart; Stassen, Jean Marie; Vergote, Ignace; Amant, Frédéric

2013-02-01

Placental growth factor (PlGF), a homolog of vascular endothelial growth factor (VEGF), exerts pleiotropic functions in cancer by affecting tumor cells as well as endothelial and inflammatory cells. Moreover, PlGF expression correlates with tumor stage, recurrence, metastasis and patient outcome in different types of cancer. Recently, administration of anti-PlGF therapy reduced tumor growth and metastasis in preclinical tumor models. In the present study, we evaluated the diagnostic and prognostic value of systemic and local expression of PlGF in primary endometrial carcinomas. PlGF levels in tumor lysates (n=128) and serum (n=88) of patients with primary endometrial cancer were determined using ELISA. PlGF mRNA expression in endometrial carcinoma tissues was quantified by quantitative qRT-PCR. Results were compared to endometrial cancer stage and grade. Systemic PlGF levels were not altered in patients with endometrial cancer (FIGO stage I-II-III) as compared to healthy controls. Only in FIGO stage IV patients, serum PlGF levels were slightly increased. Local PlGF mRNA and protein expression in endometrial tumors progressively increased with tumor grade. In endometrioid carcinomas, PlGF mRNA expression was significantly increased in endometrioid grade 3 tumors as compared to normal endometrial tissue. PlGF protein expression was significantly increased in endometrioid grade 2 and 3 carcinomas and in serous carcinomas as compared to normal endometrial tissue. Our study showed that systemic/serum PlGF levels cannot be used as a diagnostic or prognostic marker in endometrial cancer. However, the increased local expression of PlGF, primarily in high-grade carcinomas, underscores the possibility for preclinical assessment of anti-PlGF therapy in endometrial cancer.

Emulating Native Periosteum Cell Population and Subsequent Paracrine Factor Production To Promote Tissue Engineered Periosteum-Mediated Allograft Healing

PubMed Central

Hoffman, Michael D.

2015-01-01

Emulating autograft healing within the context of decellularized bone allografts has immediate clinical applications in the treatment of critical-sized bone defects. The periosteum, a thin, osteogenic tissue that surrounds bone, houses a heterogeneous population of stem cells and osteoprogenitors. There is evidence that periosteum-cell derived paracrine factors, specifically vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP2), orchestrate autograft healing through host cell recruitment and subsequent tissue elaboration. In previous work, we demonstrated that the use of poly(ethylene glycol) (PEG) hydrogels as a tissue engineered (T.E.) periosteum to localize mesenchymal stem cells (MSCs) to the surface of decellularized bone enhances allograft healing and integration. Herein, we utilize a mixed population of 50:50 MSCs and osteoprogenitor cells to better mimic native periosteum cell population and paracrine factor production to further promote allograft healing. This mixed cell population was localized to the surface of decellularized allografts within degradable hydrogels and shown to expedite allograft healing. Specifically, bone callus formation and biomechanical graft-host integration are increased as compared to unmodified allografts. These results demonstrate the dual importance of periosteum-mediated paracrine factors orchestrating host cell recruitment as well as new bone formation while developing clinically translatable strategies for allograft healing and integration. PMID:25818449

Genetics Home Reference: Fuchs endothelial dystrophy

MedlinePlus

... a protein that is part of type VIII collagen. Type VIII collagen is largely found within the cornea, surrounding the endothelial cells. Specifically, type VIII collagen is a major component of a tissue at ...

Applications of Biomaterials in Corneal Endothelial Tissue Engineering.

PubMed

Wang, Tsung-Jen; Wang, I-Jong; Hu, Fung-Rong; Young, Tai-Horng

2016-11-01

When corneal endothelial cells (CECs) are diseased or injured, corneal endothelium can be surgically removed and tissue from a deceased donor can replace the original endothelium. Recent major innovations in corneal endothelial transplantation include replacement of diseased corneal endothelium with a thin lamellar posterior donor comprising a tissue-engineered endothelium carried or cultured on a thin substratum with an organized monolayer of cells. Repairing CECs is challenging because they have restricted proliferative ability in vivo. CECs can be cultivated in vitro and seeded successfully onto natural tissue materials or synthetic polymeric materials as grafts for transplantation. The optimal biomaterials for substrata of CEC growth are being investigated. Establishing a CEC culture system by tissue engineering might require multiple biomaterials to create a new scaffold that overcomes the disadvantages of single biomaterials. Chitosan and polycaprolactone are biodegradable biomaterials approved by the Food and Drug Administration that have superior biological, degradable, and mechanical properties for culturing substratum. We successfully hybridized chitosan and polycaprolactone into blended membranes, and demonstrated that CECs proliferated, developed normal morphology, and maintained their physiological phenotypes. The interaction between cells and biomaterials is important in tissue engineering of CECs. We are still optimizing culture methods for the maintenance and differentiation of CECs on biomaterials.

Peptide-Modified Zwitterionic Porous Hydrogels for Endothelial Cell and Vascular Engineering

PubMed Central

Lin, Chih-Yeh; Wang, Yi-Ren; Lin, Che-Wei; Wang, Shih-Wen; Chien, Hsiu-Wen; Cheng, Nai-Chen; Tsai, Wei-Bor

2014-01-01

Abstract Hydrogels allow control of gel composition and mechanics, and permit incorporation of cells and a wide variety of molecules from nanoparticles to micromolecules. Peptide-linked hydrogels should tune the basic polymer into a more bioactive template to influence cellular activities. In this study, we first introduced the generation of 2D poly-(sulfobetaine methacrylate [SBMA]) hydrogel surfaces. By incorporating with functional peptide RGD and vascular endothelial growth factor-mimicking peptide KLTWQELYQLKYKG (QK) peptides, endothelial cells attached to the surface well and proliferated in a short-term culturing. However, the mechanical property, which plays a crucial role directing the cellular functions and supporting the structures, decreased when peptides graft onto hydrogels. Manipulating the mechanical property was thus necessary, and the most related factor was the monomer concentration. From our results, the higher amount of SBMA caused greater stiffness in hydrogels. Following the 2D surface studies, we fabricated 3D porous hydrogels for cell scaffolds by several methods. The salt/particle leaching method showed a more reliable way than gas-foaming method to fabricate homogeneous and open-interconnected pores within the hydrogel. Using the salt/particle leaching method, we can control the pore size before leaching. Morphology of endothelial cells within scaffolds was also investigated by scanning electron microscopy, and histological analysis was conducted in vitro and in vivo to test the biocompatibility of SB hydrogel and its potential as a therapeutic reagent for ischemic tissue repair in mice. PMID:25469315

Identification, emergence and mobilization of circulating endothelial cells or progenitors in the embryo.

PubMed

Pardanaud, Luc; Eichmann, Anne

2006-07-01

Using quail-chick parabiosis and QH1 monoclonal antibody analysis, we have identified circulating endothelial cells and/or progenitors in the embryo. These cells were already present early in ontogeny, before the third embryonic day. Under normal conditions, they integrated into most tissues but remained scarce. When experimental angiogenic responses were induced by wounding or grafts onto the chorioallantoic membrane, circulating endothelial cells were rapidly mobilized and selectively integrated sites of neoangiogenesis. Their mobilization was not dependent on the presence of the bone marrow as it was effective before its differentiation. Surprisingly, mobilization was not effective during sprouting angiogenesis following VEGF treatment of chorioallantoic membrane. Thus, embryonic circulating endothelial cells were efficiently mobilized during the establishment of an initial vascular supply to ischemic tissues following wounding or grafting, but were not involved during classical sprouting angiogenesis.

A New Bone Substitute Developed from 3D-Prints of Polylactide (PLA) Loaded with Collagen I: An In Vitro Study.

PubMed

Ritz, Ulrike; Gerke, Rebekka; Götz, Hermann; Stein, Stefan; Rommens, Pol Maria

2017-11-29

Although a lot of research has been performed, large segmental bone defects caused by trauma, infection, bone tumors or revision surgeries still represent big challenges for trauma surgeons. New and innovative bone substitutes are needed. Three-dimensional (3D) printing is a novel procedure to create 3D porous scaffolds that can be used for bone tissue engineering. In the present study, solid discs as well as porous cage-like 3D prints made of polylactide (PLA) are coated or filled with collagen, respectively, and tested for biocompatibility and endotoxin contamination. Microscopic analyses as well as proliferation assays were performed using various cell types on PLA discs. Stromal-derived factor (SDF-1) release from cages filled with collagen was analyzed and the effect on endothelial cells tested. This study confirms the biocompatibility of PLA and demonstrates an endotoxin contamination clearly below the FDA (Food and Drug Administration) limit. Cells of various cell types (osteoblasts, osteoblast-like cells, fibroblasts and endothelial cells) grow, spread and proliferate on PLA-printed discs. PLA cages loaded with SDF-1 collagen display a steady SDF-1 release, support cell growth of endothelial cells and induce neo-vessel formation. These results demonstrate the potential for PLA scaffolds printed with an inexpensive desktop printer in medical applications, for example, in bone tissue engineering.

A New Bone Substitute Developed from 3D-Prints of Polylactide (PLA) Loaded with Collagen I: An In Vitro Study

PubMed Central

Gerke, Rebekka; Götz, Hermann; Rommens, Pol Maria

2017-01-01

Although a lot of research has been performed, large segmental bone defects caused by trauma, infection, bone tumors or revision surgeries still represent big challenges for trauma surgeons. New and innovative bone substitutes are needed. Three-dimensional (3D) printing is a novel procedure to create 3D porous scaffolds that can be used for bone tissue engineering. In the present study, solid discs as well as porous cage-like 3D prints made of polylactide (PLA) are coated or filled with collagen, respectively, and tested for biocompatibility and endotoxin contamination. Microscopic analyses as well as proliferation assays were performed using various cell types on PLA discs. Stromal-derived factor (SDF-1) release from cages filled with collagen was analyzed and the effect on endothelial cells tested. This study confirms the biocompatibility of PLA and demonstrates an endotoxin contamination clearly below the FDA (Food and Drug Administration) limit. Cells of various cell types (osteoblasts, osteoblast-like cells, fibroblasts and endothelial cells) grow, spread and proliferate on PLA-printed discs. PLA cages loaded with SDF-1 collagen display a steady SDF-1 release, support cell growth of endothelial cells and induce neo-vessel formation. These results demonstrate the potential for PLA scaffolds printed with an inexpensive desktop printer in medical applications, for example, in bone tissue engineering. PMID:29186036

The synthetic triterpenoid RTA dh404 (CDDO-dhTFEA) restores endothelial function impaired by reduced Nrf2 activity in chronic kidney disease.

PubMed

Aminzadeh, Mohammad A; Reisman, Scott A; Vaziri, Nosratola D; Shelkovnikov, Stan; Farzaneh, Seyed H; Khazaeli, Mahyar; Meyer, Colin J

2013-01-01

Chronic kidney disease (CKD) is associated with endothelial dysfunction and accelerated cardiovascular disease, which are largely driven by systemic oxidative stress and inflammation. Oxidative stress and inflammation in CKD are associated with and, in part, due to impaired activity of the cytoprotective transcription factor Nrf2. RTA dh404 is a synthetic oleanane triterpenoid compound which potently activates Nrf2 and inhibits the pro-inflammatory transcription factor NF-κB. This study was designed to test the effects of RTA dh404 on endothelial function, inflammation, and the Nrf2-mediated antioxidative system in the aorta of rats with CKD induced by 5/6 nephrectomy. Sham-operated rats served as controls. Subgroups of CKD rats were treated orally with RTA dh404 (2 mg/kg/day) or vehicle for 12 weeks. The aortic rings from untreated CKD rats exhibited a significant reduction in the acetylcholine-induced relaxation response which was restored by RTA dh404 administration. Impaired endothelial function in the untreated CKD rats was accompanied by significant reduction of Nrf2 activity (nuclear translocation) and expression of its cytoprotective target genes, as well as accumulation of nitrotyrosine and upregulation of NAD(P)H oxidases, 12-lipoxygenase, MCP-1, and angiotensin II receptors in the aorta. These abnormalities were ameliorated by RTA dh404 administration, as demonstrated by the full or partial restoration of the expression of all the above analytes to sham control levels. Collectively, the data demonstrate that endothelial dysfunction in rats with CKD induced by 5/6 nephrectomy is associated with impaired Nrf2 activity in arterial tissue, which can be reversed with long term administration of RTA dh404.

Treatment with platelet lysate induces endothelial differentation of bone marrow mesenchymal stem cells under fluid shear stress

PubMed Central

Homayouni Moghadam, Farshad; Tayebi, Tahereh; Moradi, Alireza; Nadri, Hamid; Barzegar, Kazem; Eslami, Gilda

2014-01-01

By considering stem cell-based therapies as a new hope for the treatment of some tragic diseases, marrow stromal cells or marrow mesenchymal stem cells (MSCs) were considered as a suitable and safe multipotential cell source for this new therapeutic approach. For this purpose, many investigations have been performed on differentiation of MSCs toward specific cell lines to overcome the demand for providing the organ specific cells for cell therapy or preparation of engineered tissues. In the present study, differentiation of MSCs to endothelial cells (ECs) by mechanical and chemical stimulation was evaluated. Fluid shear stress (FSS) was used as mechanical inducer, while platelet lysate (PL) and estradiol (E) were used as chemical induction factors. MSCs were placed under FSS with different forces (2, 5 and 10dyn/cm2) for different periods (6, 12 and 24 hours). In some groups, PL and E were added to the culture media to evaluate their effect on expression of EC specific markers. This investigation revealed that FSS with low tension (2.5-5 dyn/cm2) for a long time (24 hours) or high tension (10 dyn/cm2) in short time (6 hours) in the presence of PL could differentiate MSCs toward ECs. The presence of PL was necessary for initiation of endothelial differentiation, and in the absence of PL, there was not any expression of CD34 and Cadherin5 (Cdh5) among cells. Adding E to the culture medium did not change the rate of endothelial differentiation under FSS. Generated endothelial progenitors could produce von Willebrand factor (vWF) after two weeks culture and also they formed tubular structures after culture on matrigel. PMID:26417289

Treatment with platelet lysate induces endothelial differentation of bone marrow mesenchymal stem cells under fluid shear stress.

PubMed

Homayouni Moghadam, Farshad; Tayebi, Tahereh; Moradi, Alireza; Nadri, Hamid; Barzegar, Kazem; Eslami, Gilda

2014-01-01

By considering stem cell-based therapies as a new hope for the treatment of some tragic diseases, marrow stromal cells or marrow mesenchymal stem cells (MSCs) were considered as a suitable and safe multipotential cell source for this new therapeutic approach. For this purpose, many investigations have been performed on differentiation of MSCs toward specific cell lines to overcome the demand for providing the organ specific cells for cell therapy or preparation of engineered tissues. In the present study, differentiation of MSCs to endothelial cells (ECs) by mechanical and chemical stimulation was evaluated. Fluid shear stress (FSS) was used as mechanical inducer, while platelet lysate (PL) and estradiol (E) were used as chemical induction factors. MSCs were placed under FSS with different forces (2, 5 and 10dyn/cm(2)) for different periods (6, 12 and 24 hours). In some groups, PL and E were added to the culture media to evaluate their effect on expression of EC specific markers. This investigation revealed that FSS with low tension (2.5-5 dyn/cm(2)) for a long time (24 hours) or high tension (10 dyn/cm(2)) in short time (6 hours) in the presence of PL could differentiate MSCs toward ECs. The presence of PL was necessary for initiation of endothelial differentiation, and in the absence of PL, there was not any expression of CD34 and Cadherin5 (Cdh5) among cells. Adding E to the culture medium did not change the rate of endothelial differentiation under FSS. Generated endothelial progenitors could produce von Willebrand factor (vWF) after two weeks culture and also they formed tubular structures after culture on matrigel.

Endothelial fibroblast growth factor receptor signaling is required for vascular remodeling following cardiac ischemia-reperfusion injury

PubMed Central

Castro, Angela M.; Lupu, Traian S.; Weinheimer, Carla; Smith, Craig; Kovacs, Attila

2016-01-01

Fibroblast growth factor (FGF) signaling is cardioprotective in various models of myocardial infarction. FGF receptors (FGFRs) are expressed in multiple cell types in the adult heart, but the cell type-specific FGFR signaling that mediates different cardioprotective endpoints is not known. To determine the requirement for FGFR signaling in endothelium in cardiac ischemia-reperfusion injury, we conditionally inactivated the Fgfr1 and Fgfr2 genes in endothelial cells with Tie2-Cre (Tie2-Cre, Fgfr1f/f, Fgfr2f/f DCKO mice). Tie2-Cre, Fgfr1f/f, Fgfr2f/f DCKO mice had normal baseline cardiac morphometry, function, and vessel density. When subjected to closed-chest, regional cardiac ischemia-reperfusion injury, Tie2-Cre, Fgfr1f/f, Fgfr2f/f DCKO mice showed a significantly increased hypokinetic area at 7 days, but not 1 day, after reperfusion. Tie2-Cre, Fgfr1f/f, Fgfr2f/f DCKO mice also showed significantly worsened cardiac function compared with controls at 7 days but not 1 day after reperfusion. Pathophysiological analysis showed significantly decreased vessel density, increased endothelial cell apoptosis, and worsened tissue hypoxia in the peri-infarct area at 7 days following reperfusion. Notably, Tie2-Cre, Fgfr1f/f, Fgfr2f/f DCKO mice showed no impairment in the cardiac hypertrophic response. These data demonstrate an essential role for FGFR1 and FGFR2 in endothelial cells for cardiac functional recovery and vascular remodeling following in vivo cardiac ischemia-reperfusion injury, without affecting the cardiac hypertrophic response. This study suggests the potential for therapeutic benefit from activation of endothelial FGFR pathways following ischemic injury to the heart. PMID:26747503

Fatty Acid Binding Protein 4 Deficiency Protects against Oxygen-Induced Retinopathy in Mice

PubMed Central

Saint-Geniez, Magali; Ghelfi, Elisa; Liang, Xiaoliang; Yu, Chenwei; Spencer, Carrie; Abend, Stephanie; Hotamisligil, Gokhan; Cataltepe, Sule

2014-01-01

Retinopathy of prematurity (ROP) is a leading cause of blindness in children worldwide due to increasing survival rates of premature infants. Initial suppression, followed by increased production of the retinal vascular endothelial growth factor-A (VEGF) expression are key events that trigger the pathological neovascularization in ROP. Fatty acid binding protein 4 (FABP4) is an intracellular lipid chaperone that is induced by VEGF in a subset of endothelial cells. FABP4 exhibits a pro-angiogenic function in cultured endothelial cells and in airway microvasculature, but whether it plays a role in modulation of retinal angiogenesis is not known. We hypothesized that FABP4 deficiency could ameliorate pathological retinal vascularization and investigated this hypothesis using a well-characterized mouse model of oxygen-induced retinopathy (OIR). We found that FABP4 was not expressed in retinal vessels, but was present in resident macrophages/microglial cells and endothelial cells of the hyaloid vasculature in the immature retina. While FABP4 expression was not required for normal development of retinal vessels, FABP4 expression was upregulated and localized to neovascular tufts in OIR. FABP4−/− mice demonstrated a significant decrease in neovessel formation as well as a significant improvement in physiological revascularization of the avascular retinal tissues. These alterations in retinal vasculature were accompanied by reduced endothelial cell proliferation, but no effect on apoptosis or macrophage/microglia recruitment. FABP4−/− OIR samples demonstrated decreased expression of genes involved in angiogenesis, such as Placental Growth Factor, and angiopoietin 2. Collectively, our findings suggest FABP4 as a potential target of pathologic retinal angiogenesis in proliferative retinopathies. PMID:24802082

Endothelial fibroblast growth factor receptor signaling is required for vascular remodeling following cardiac ischemia-reperfusion injury.

PubMed

House, Stacey L; Castro, Angela M; Lupu, Traian S; Weinheimer, Carla; Smith, Craig; Kovacs, Attila; Ornitz, David M

2016-03-01

Fibroblast growth factor (FGF) signaling is cardioprotective in various models of myocardial infarction. FGF receptors (FGFRs) are expressed in multiple cell types in the adult heart, but the cell type-specific FGFR signaling that mediates different cardioprotective endpoints is not known. To determine the requirement for FGFR signaling in endothelium in cardiac ischemia-reperfusion injury, we conditionally inactivated the Fgfr1 and Fgfr2 genes in endothelial cells with Tie2-Cre (Tie2-Cre, Fgfr1(f/f), Fgfr2(f/f) DCKO mice). Tie2-Cre, Fgfr1(f/f), Fgfr2(f/f) DCKO mice had normal baseline cardiac morphometry, function, and vessel density. When subjected to closed-chest, regional cardiac ischemia-reperfusion injury, Tie2-Cre, Fgfr1(f/f), Fgfr2(f/f) DCKO mice showed a significantly increased hypokinetic area at 7 days, but not 1 day, after reperfusion. Tie2-Cre, Fgfr1(f/f), Fgfr2(f/f) DCKO mice also showed significantly worsened cardiac function compared with controls at 7 days but not 1 day after reperfusion. Pathophysiological analysis showed significantly decreased vessel density, increased endothelial cell apoptosis, and worsened tissue hypoxia in the peri-infarct area at 7 days following reperfusion. Notably, Tie2-Cre, Fgfr1(f/f), Fgfr2(f/f) DCKO mice showed no impairment in the cardiac hypertrophic response. These data demonstrate an essential role for FGFR1 and FGFR2 in endothelial cells for cardiac functional recovery and vascular remodeling following in vivo cardiac ischemia-reperfusion injury, without affecting the cardiac hypertrophic response. This study suggests the potential for therapeutic benefit from activation of endothelial FGFR pathways following ischemic injury to the heart. Copyright © 2016 the American Physiological Society.

Engineering the mechanical and biological properties of nanofibrous vascular grafts for in situ vascular tissue engineering.

PubMed

Henry, Jeffrey J D; Yu, Jian; Wang, Aijun; Lee, Randall; Fang, Jun; Li, Song

2017-08-17

Synthetic small diameter vascular grafts have a high failure rate, and endothelialization is critical for preventing thrombosis and graft occlusion. A promising approach is in situ tissue engineering, whereby an acellular scaffold is implanted and provides stimulatory cues to guide the in situ remodeling into a functional blood vessel. An ideal scaffold should have sufficient binding sites for biomolecule immobilization and a mechanical property similar to native tissue. Here we developed a novel method to blend low molecular weight (LMW) elastic polymer during electrospinning process to increase conjugation sites and to improve the mechanical property of vascular grafts. LMW elastic polymer improved the elasticity of the scaffolds, and significantly increased the amount of heparin conjugated to the micro/nanofibrous scaffolds, which in turn increased the loading capacity of vascular endothelial growth factor (VEGF) and prolonged the release of VEGF. Vascular grafts were implanted into the carotid artery of rats to evaluate the in vivo performance. VEGF treatment significantly enhanced endothelium formation and the overall patency of vascular grafts. Heparin coating also increased cell infiltration into the electrospun grafts, thus increasing the production of collagen and elastin within the graft wall. This work demonstrates that LMW elastic polymer blending is an approach to engineer the mechanical and biological property of micro/nanofibrous vascular grafts for in situ vascular tissue engineering.

Von Willebrand Factor Deposition and ADAMTS-13 Consumption in Allograft Tissue of Thrombotic Microangiopathy-like Disorder After Living Donor Liver Transplantation: A Case Report.

PubMed

Nakanuma, S; Miyashita, T; Hayashi, H; Ohbatake, Y; Takamura, H; Okazaki, M; Yamaguchi, T; Sakai, S; Makino, I; Oyama, K; Tajima, H; Ninomiya, I; Fushida, S; Ohta, T

2017-09-01

Thrombotic microangiopathy (TMA) pathogenesis after living donor liver transplantation (LDLT) is thought to be caused by release of unusually large von Willebrand factor multimers (UL-vWFMs) resulting from sinusoidal endothelial cell damage and induction of platelet adhesion and aggregation. A decrease in a disintegrin-like and metalloproteinase with thrombospondin type 1 motifs-13 (ADAMTS-13) that cleave UL-vWFMs might cause excessive UL-vWFMs activity and result in platelet thrombus formation. However, this phenomenon has not undergone a full pathologic assessment. A 60-year-old man was diagnosed with hepatitis C-related end-stage cirrhosis. His son was the donor, and he underwent LDLT. On postoperative day 44, his laboratory findings met most TMA diagnostic criteria, and he was diagnosed with TMA-like disorder (TMALD). Localization of CD42b as a platelet marker, vWF, and ADAMTS-13 in allograft tissue of this patient were evaluated using immunohistochemistry. CD42b expression was observed as platelet aggregates attached to hepatocytes or within the hepatocyte cytoplasm, a morphology called extravasated platelet aggregation (EPA). vWF expression was observed mainly as deposited compact clusters, and ADAMTS-13 expression resembled distinct dots throughout the liver tissue. These findings suggest that EPA indicated sinusoidal endothelial cell damage followed by detachment, and vWF deposition resulted from UL-vWFM oversynthesis. ADAMTS-13 might be consumed in the allograft tissue to cleave UL-vWFMs, but ADAMTS-13 levels might be insufficient to cleave all the deposited UL-vWFMs. We present the case of an LDLT recipient diagnosed with TMALD using blood tests, which showed the presence of TMA pathogenesis in the allograft. Copyright © 2017 Elsevier Inc. All rights reserved.

In vitro fabrication of functional three-dimensional tissues with perfusable blood vessels

PubMed Central

Sekine, Hidekazu; Shimizu, Tatsuya; Sakaguchi, Katsuhisa; Dobashi, Izumi; Wada, Masanori; Yamato, Masayuki; Kobayashi, Eiji; Umezu, Mitsuo; Okano, Teruo

2013-01-01

In vitro fabrication of functional vascularized three-dimensional tissues has been a long-standing objective in the field of tissue engineering. Here we report a technique to engineer cardiac tissues with perfusable blood vessels in vitro. Using resected tissue with a connectable artery and vein as a vascular bed, we overlay triple-layer cardiac cell sheets produced from coculture with endothelial cells, and support the tissue construct with media perfused in a bioreactor. We show that endothelial cells connect to capillaries in the vascular bed and form tubular lumens, creating in vitro perfusable blood vessels in the cardiac cell sheets. Thicker engineered tissues can be produced in vitro by overlaying additional triple-layer cell sheets. The vascularized cardiac tissues beat and can be transplanted with blood vessel anastomoses. This technique may create new opportunities for in vitro tissue engineering and has potential therapeutic applications. PMID:23360990

Bacillus anthracis-derived edema toxin (ET) counter-regulates movement of neutrophils and macromolecules through the endothelial paracellular pathway.

PubMed

Nguyen, Chinh; Feng, Chiguang; Zhan, Min; Cross, Alan S; Goldblum, Simeon E

2012-01-09

A common finding amongst patients with inhalational anthrax is a paucity of polymorphonuclear leukocytes (PMNs) in infected tissues in the face of abundant circulating PMNs. A major virulence determinant of anthrax is edema toxin (ET), which is formed by the combination of two proteins produced by the organism, edema factor (EF), which is an adenyl cyclase, and protective antigen (PA). Since cAMP, a product of adenyl cyclase, is known to enhance endothelial barrier integrity, we asked whether ET might decrease extravasation of PMNs into tissues through closure of the paracellular pathway through which PMNs traverse. Pretreatment of human microvascular endothelial cell(EC)s of the lung (HMVEC-L) with ET decreased interleukin (IL)-8-driven transendothelial migration (TEM) of PMNs with a maximal reduction of nearly 60%. This effect required the presence of both EF and PA. Conversely, ET did not diminish PMN chemotaxis in an EC-free system. Pretreatment of subconfluent HMVEC-Ls decreased transendothelial 14 C-albumin flux by ~ 50% compared to medium controls. Coadministration of ET with either tumor necrosis factor-α or bacterial lipopolysaccharide, each at 100 ng/mL, attenuated the increase of transendothelial 14 C-albumin flux caused by either agent alone. The inhibitory effect of ET on TEM paralleled increases in protein kinase A (PKA) activity, but could not be blocked by inhibition of PKA with either H-89 or KT-5720. Finally, we were unable to replicate the ET effect with either forskolin or 3-isobutyl-1-methylxanthine, two agents known to increase cAMP. We conclude that ET decreases IL-8-driven TEM of PMNs across HMVEC-L monolayers independent of cAMP/PKA activity.

CD147 promotes liver fibrosis progression via VEGF-A/VEGFR2 signalling-mediated cross-talk between hepatocytes and sinusoidal endothelial cells.

PubMed

Yan, Zhaoyong; Qu, Kai; Zhang, Jing; Huang, Qichao; Qu, Ping; Xu, Xinsen; Yuan, Peng; Huang, Xiaojun; Shao, Yongping; Liu, Chang; Zhang, Hongxin; Xing, Jinliang

2015-10-01

Although previous evidence indicates close involvement of CD147 in the pathogenesis of liver fibrosis, the underlying molecular mechanisms and its therapeutic value remain largely unknown. In the present study, we investigated the biological roles of CD147 in liver fibrosis and assessed its therapeutic value as a target molecule in the CCl4-induced liver fibrosis mouse model. We found that CD147 was highly expressed in both hepatocytes and SECs (sinusoidal endothelial cells) in fibrotic liver tissues. Additionally, it was significantly associated with the fibrosis stage. TGF-β1 (transforming growth factor β1) was found to be mainly responsible for the up-regulation of CD147. Bioinformatic and experimental data suggest a functional link between CD147 expression and VEGF-A (vascular endothelial growth factor A)/VEGR-2 (VEGF receptor 2) signalling-mediated angiogenesis in fibrotic liver tissues. Furthermore, we observed that the CD147-induced activation of the PI3K (phosphoinositide 3-kinase)/Akt signalling pathway promotes the production of VEGF-A in hepatocytes and expression of VEGFR-2 in SECs, which was found to enhance the angiogenic capability of SECs. Finally, our data indicate that blocking of CD147 using an mAb (monoclonal antibody) attenuated liver fibrosis progression via inhibition of VEGF-A/VEGFR-2 signalling and subsequent amelioration of microvascular abnormality in the CCl4-induced mouse model. Our findings suggest a novel functional mechanism that CD147 may promote liver fibrosis progression via inducing the VEGF-A/VEGFR-2 signalling pathway-mediated cross-talk between hepatocytes and SECs. New strategies based on the intervention of CD147 can be expected for prevention of liver fibrosis. © 2015 Authors; published by Portland Press Limited.

Signaling of Prostaglandin E Receptors, EP3 and EP4 Facilitates Wound Healing and Lymphangiogenesis with Enhanced Recruitment of M2 Macrophages in Mice.

PubMed

Hosono, Kanako; Isonaka, Risa; Kawakami, Tadashi; Narumiya, Shuh; Majima, Masataka

2016-01-01

Lymphangiogenesis plays an important role in homeostasis, metabolism, and immunity, and also occurs during wound-healing. Here, we examined the roles of prostaglandin E2 (PGE2) receptor (EP) signaling in enhancement of lymphangiogenesis in wound healing processes. The hole-punch was made in the ears of male C57BL/6 mice using a metal ear punch. Healing process and lymphangiogenesis together with macrophage recruitment were analyzed in EP knockout mice. Lymphangiogenesis was up-regulated in the granulation tissues at the margins of punched-hole wounds in mouse ears, and this increase was accompanied by increased expression levels of COX-2 and microsomal prostaglandin E synthase-1. Administration of celecoxib, a COX-2 inhibitor, suppressed lymphangiogenesis in the granulation tissues and reduced the induction of the pro-lymphangiogenic factors, vascular endothelial growth factor (VEGF) -C and VEGF-D. Topical applications of selective EP receptor agonists enhanced the expressions of lymphatic vessel endothelial hyaluronan receptor-1 and VEGF receptor-3. The wound-healing processes and recruitment of CD11b-positive macrophages, which produced VEGF-C and VEGF-D, were suppressed under COX-2 inhibition. Mice lacking either EP3 or EP4 exhibited reduced wound-healing, lymphangiogenesis and recruitment of M2 macrophages, compared with wild type mice. Proliferation of cultured human lymphatic endothelial cells was not detected under PGE2 stimulation. Lymphangiogenesis and recruitment of M2 macrophages that produced VEGF-C/D were suppressed in mice treated with a COX-2 inhibitor or lacking either EP3 or EP4 during wound healing. COX-2 and EP3/EP4 signaling may be novel targets to control lymphangiogenesis in vivo.

Efficacy of Sunitinib and Radiotherapy in Genetically Engineered Mouse Model of Soft-Tissue Sarcoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoon, Sam S.; Stangenberg, Lars; Lee, Yoon-Jin

Purpose: Sunitinib (SU) is a multitargeted receptor tyrosine kinase inhibitor of the vascular endothelial growth factor and platelet-derived growth factor receptors. The present study examined SU and radiotherapy (RT) in a genetically engineered mouse model of soft tissue sarcoma (STS). Methods and Materials: Primary extremity STSs were generated in genetically engineered mice. The mice were randomized to treatment with SU, RT (10 Gy x 2), or both (SU+RT). Changes in the tumor vasculature before and after treatment were assessed in vivo using fluorescence-mediated tomography. The control and treated tumors were harvested and extensively analyzed. Results: The mean fluorescence in themore » tumors was not decreased by RT but decreased 38-44% in tumors treated with SU or SU+RT. The control tumors grew to a mean of 1378 mm{sup 3} after 12 days. SU alone or RT alone delayed tumor growth by 56% and 41%, respectively, but maximal growth inhibition (71%) was observed with the combination therapy. SU target effects were confirmed by loss of target receptor phosphorylation and alterations in SU-related gene expression. Cancer cell proliferation was decreased and apoptosis increased in the SU and RT groups, with a synergistic effect on apoptosis observed in the SU+RT group. RT had a minimal effect on the tumor microvessel density and endothelial cell-specific apoptosis, but SU alone or SU+RT decreased the microvessel density by >66% and induced significant endothelial cell apoptosis. Conclusion: SU inhibited STS growth by effects on both cancer cells and tumor vasculature. SU also augmented the efficacy of RT, suggesting that this combination strategy could improve local control of STS.« less

Three-dimensional bioprinting of thick vascularized tissues

NASA Astrophysics Data System (ADS)

Kolesky, David B.; Homan, Kimberly A.; Skylar-Scott, Mark A.; Lewis, Jennifer A.

2016-03-01

The advancement of tissue and, ultimately, organ engineering requires the ability to pattern human tissues composed of cells, extracellular matrix, and vasculature with controlled microenvironments that can be sustained over prolonged time periods. To date, bioprinting methods have yielded thin tissues that only survive for short durations. To improve their physiological relevance, we report a method for bioprinting 3D cell-laden, vascularized tissues that exceed 1 cm in thickness and can be perfused on chip for long time periods (>6 wk). Specifically, we integrate parenchyma, stroma, and endothelium into a single thick tissue by coprinting multiple inks composed of human mesenchymal stem cells (hMSCs) and human neonatal dermal fibroblasts (hNDFs) within a customized extracellular matrix alongside embedded vasculature, which is subsequently lined with human umbilical vein endothelial cells (HUVECs). These thick vascularized tissues are actively perfused with growth factors to differentiate hMSCs toward an osteogenic lineage in situ. This longitudinal study of emergent biological phenomena in complex microenvironments represents a foundational step in human tissue generation.

Enamel matrix derivative, inflammation and soft tissue wound healing.

PubMed

Miron, R J; Dard, M; Weinreb, M

2015-10-01

Over 15 years have now passed since enamel matrix derivative (EMD) emerged as an agent capable of periodontal regeneration. Following thorough investigation, evidenced-based clinical application is now established for a multitude of clinical settings to promote regeneration of periodontal hard tissues. Despite the large number of studies and review articles written on this topic, no single review has compiled the influence of EMD on tissue inflammation, an area of research that merits substantial attention in periodontology. The aim of the present review was to gather all studies that deal with the effects of EMD on tissue inflammation with particular interest in the cellular mechanisms involved in inflammation and soft tissue wound healing/resolution. The effects of EMD on monocytes, macrophages, lymphocytes, neutrophils, fibroblasts and endothelial cells were investigated for changes in cell behavior as well as release of inflammatory markers, including interleukins, prostaglandins, tumor necrosis factor-α, matrix metalloproteinases and members of the OPG-RANKL pathway. In summary, studies listed in this review have reported that EMD is able to significantly decrease interleukin-1b and RANKL expression, increase prostaglandin E2 and OPG expression, increase proliferation and migration of T lymphocytes, induce monocyte differentiation, increase bacterial and tissue debris clearance, as well as increase fibroplasias and angiogenesis by inducing endothelial cell proliferation, migration and capillary-like sprout formation. The outcomes from the present review article indicate that EMD is able to affect substantially the inflammatory and healing responses and lay the groundwork for future investigation in the field. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Differential expression of VEGF ligands and receptors in prostate cancer.

PubMed

Woollard, David J; Opeskin, Kenneth; Coso, Sanja; Wu, Di; Baldwin, Megan E; Williams, Elizabeth D

2013-05-01

Prostate cancer disseminates to regional lymph nodes, however the molecular mechanisms responsible for lymph node metastasis are poorly understood. The vascular endothelial growth factor (VEGF) ligand and receptor family have been implicated in the growth and spread of prostate cancer via activation of the blood vasculature and lymphatic systems. The purpose of this study was to comprehensively examine the expression pattern of VEGF ligands and receptors in the glandular epithelium, stroma, lymphatic vasculature and blood vessels in prostate cancer. The localization of VEGF-A, VEGF-C, VEGF-D, VEGF receptor (VEGFR)-1, VEGFR-2, and VEGFR-3 was examined in cancerous and adjacent benign prostate tissue from 52 subjects representing various grades of prostate cancer. Except for VEGFR-2, extensive staining was observed for all ligands and receptors in the prostate specimens. In epithelial cells, VEGF-A and VEGFR-1 expression was higher in tumor tissue compared to benign tissue. VEGF-D and VEGFR-3 expression was significantly higher in benign tissue compared to tumor in the stroma and the endothelium of lymphatic and blood vessels. In addition, the frequency of lymphatic vessels, but not blood vessels, was lower in tumor tissue compared with benign tissue. These results suggest that activation of VEGFR-1 by VEGF-A within the carcinoma, and activation of lymphatic endothelial cell VEGFR-3 by VEGF-D within the adjacent benign stroma may be important signaling mechanisms involved in the progression and subsequent metastatic spread of prostate cancer. Thus inhibition of these pathways may contribute to therapeutic strategies for the management of prostate cancer. Copyright © 2012 Wiley Periodicals, Inc.

Granulocyte colony-stimulating factor mobilizes functional endothelial progenitor cells in patients with coronary artery disease.

PubMed

Powell, Tiffany M; Paul, Jonathan D; Hill, Jonathan M; Thompson, Michael; Benjamin, Moshe; Rodrigo, Maria; McCoy, J Philip; Read, Elizabeth J; Khuu, Hanh M; Leitman, Susan F; Finkel, Toren; Cannon, Richard O

2005-02-01

Endothelial progenitor cells (EPCs) that may repair vascular injury are reduced in patients with coronary artery disease (CAD). We reasoned that EPC number and function may be increased by granulocyte colony-stimulating factor (G-CSF) used to mobilize hematopoietic progenitor cells in healthy donors. Sixteen CAD patients had reduced CD34(+)/CD133(+) (0.0224+/-0.0063% versus 0.121+/-0.038% mononuclear cells [MNCs], P<0.01) and CD133(+)/VEGFR-2(+) cells, consistent with EPC phenotype (0.00033+/-0.00015% versus 0.0017+/-0.0006% MNCs, P<0.01), compared with 7 healthy controls. Patients also had fewer clusters of cells in culture, with out-growth consistent with mature endothelial phenotype (2+/-1/well) compared with 16 healthy subjects at high risk (13+/-4/well, P<0.05) or 14 at low risk (22+/-3/well, P<0.001) for CAD. G-CSF 10 microg/kg per day for 5 days increased CD34(+)/CD133(+) cells from 0.5+/-0.2/microL to 59.5+/-10.6/microL and CD133(+)/ VEGFR-2(+) cells from 0.007+/-0.004/microL to 1.9+/-0.6/microL (both P<0.001). Also increased were CD133(+) cells that coexpressed the homing receptor CXCR4 (30.4+/-8.3/microL, P<0.05). Endothelial cell-forming clusters in 10 patients increased to 27+/-9/well after treatment (P<0.05), with a decline to 9+/-4/well at 2 weeks (P=0.06). Despite reduced EPCs compared with healthy controls, patients with CAD respond to G-CSF with increases in EPC number and homing receptor expression in the circulation and endothelial out-growth in culture. Endothelial progenitor cells (EPCs) are reduced in coronary artery disease. Granulocyte colony-stimulating factor (CSF) administered to patients increased: (1) CD133+/VEGFR-2+ cells consistent with EPC phenotype; (2) CD133+ cells coexpressing the chemokine receptor CXCR4, important for homing of EPCs to ischemic tissue; and (3) endothelial cell-forming clusters in culture. Whether EPCs mobilized into the circulation will be useful for the purpose of initiating vascular growth and myocyte repair in coronary artery disease patients must be tested in clinical trials.

MMP‐2 and MMP‐14 Silencing Inhibits VEGFR2 Cleavage and Induces the Differentiation of Porcine Adipose‐Derived Mesenchymal Stem Cells to Endothelial Cells

PubMed Central

Almalki, Sami G.; Llamas Valle, Yovani

2017-01-01

Abstract The molecular mechanisms that control the ability of adipose‐derived mesenchymal stem cells (AMSCs) to remodel three‐dimensional extracellular matrix barriers during differentiation are not clearly understood. Herein, we studied the expression of matrix metalloproteinases (MMPs) during the differentiation of AMSCs to endothelial cells (ECs) in vitro. MSCs were isolated from porcine abdominal adipose tissue, and characterized by immunopositivity to CD44, CD90, CD105, and immunonegativity to CD14 and CD45. Plasticity of AMSCs was confirmed by multilineage differentiation. The mRNA transcripts for MMPs and Tissue Inhibitor of Metalloproteinases (TIMPs), and protein expression of EC markers were analyzed. The enzyme activity and protein expression were analyzed by gelatin zymography, enzyme‐linked immunosorbent assay (ELISA), and Western blot. The differentiation of AMSCs to ECs was confirmed by mRNA and protein expressions of the endothelial markers. The mRNA transcripts for MMP‐2 and MMP‐14 were significantly increased during the differentiation of MSCs into ECs. Findings revealed an elevated MMP‐14 and MMP‐2 expression, and MMP2 enzyme activity. Silencing of MMP‐2 and MMP‐14 significantly increased the expression of EC markers, formation of capillary tubes, and acetylated‐low‐density lipoprotein uptake, and decreased the cleavage of vascular endothelial growth factor receptor type 2 (VEGFR2). Inhibition of VEGFR2 significantly decreased the expression of EC markers. These novel findings demonstrate that the upregulation of MMP2 and MMP14 has an inhibitory effect on the differentiation of AMSCs to ECs, and silencing these MMPs inhibit the cleavage of VEGFR2 and stimulate the differentiation of AMSCs to ECs. These findings provide a potential mechanism for the regulatory role of MMP‐2 and MMP‐14 in the re‐endothelialization of coronary arteries following intervention. Stem Cells Translational Medicine 2017;6:1385–1398 PMID:28213979

Monosialoganglioside-Containing Nanoliposomes Restore Endothelial Function Impaired by AL Amyloidosis Light Chain Proteins.

PubMed

Franco, Daniel A; Truran, Seth; Weissig, Volkmar; Guzman-Villanueva, Diana; Karamanova, Nina; Senapati, Subhadip; Burciu, Camelia; Ramirez-Alvarado, Marina; Blancas-Mejia, Luis M; Lindsay, Stuart; Hari, Parameswaran; Migrino, Raymond Q

2016-06-13

Light chain amyloidosis (AL) is associated with high mortality, especially in patients with advanced cardiovascular involvement. It is caused by toxicity of misfolded light chain proteins (LC) in vascular, cardiac, and other tissues. There is no treatment to reverse LC tissue toxicity. We tested the hypothesis that nanoliposomes composed of monosialoganglioside, phosphatidylcholine, and cholesterol (GM1 ganglioside-containing nanoliposomes [NLGM1]) can protect against LC-induced human microvascular dysfunction and assess mechanisms behind the protective effect. The dilator responses of ex vivo abdominal adipose arterioles from human participants without AL to acetylcholine and papaverine were measured before and after exposure to LC (20 μg/mL) with or without NLGM1 (1:10 ratio for LC:NLGM1 mass). Human umbilical vein endothelial cells were exposed for 18 to 20 hours to vehicle, LC with or without NLGM1, or NLGM1 and compared for oxidative and nitrative stress response and cellular viability. LC impaired arteriole dilator response to acetylcholine, which was restored by co-treatment with NLGM1. LC decreased endothelial cell nitric oxide production and cell viability while increasing superoxide and peroxynitrite; these adverse effects were reversed by NLGM1. NLGM1 increased endothelial cell protein expression of antioxidant enzymes heme oxygenase 1 and NAD(P)H quinone dehydrogenase 1 and increased nuclear factor, erythroid 2 like 2 (Nrf-2) protein. Nrf-2 gene knockdown reduced antioxidant stress response and reversed the protective effects of NLGM1. NLGM1 protects against LC-induced human microvascular endothelial dysfunction through increased nitric oxide bioavailability and reduced oxidative and nitrative stress mediated by Nrf-2-dependent antioxidant stress response. These findings point to a potential novel therapeutic approach for light chain amyloidosis. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Stem Cells Derived from Tooth Periodontal Ligament Enhance Functional Angiogenesis by Endothelial Cells

PubMed Central

Yeasmin, Shamima; Ceccarelli, Jacob; Vigen, Marina; Carrion, Bita; Putnam, Andrew J.; Tarle, Susan A.

2014-01-01

In regenerative medicine approaches involving cell therapy, selection of the appropriate cell type is important in that the cells must directly (differentiation) or indirectly (trophic effects) participate in the regenerative response. Regardless of the mode of action of the cells, angiogenesis underlies the success of these approaches. Stem cells derived from tooth tissues, specifically the periodontal ligament of teeth (periodontal ligament stem cells [PDLSCs]), have recently been identified as a good source of multipotent cells for cell therapies. PDLSCs have demonstrated properties similar to mesenchymal stem cells (MSCs), yet, unlike MSCs, their vascular potential has not been previously demonstrated. Thus, the aim of this study was to determine if PDLSCs could modulate angiogenesis. In comparison to MSCs and stem cells derived from tooth pulp tissues (SHEDs), we first determined if PDLSCs released soluble proangiogenic factors with the capacity to induce vessel formation by endothelial cells (ECs). Next, the ability of PDLSCs to modulate angiogenesis was examined through their cotransplantation with ECs in subcutaneous sites of immunocompromised mice. Finally, the stability of the PDLSC-mediated vasculature was determined through evaluation of the maturity and functionality of the vessels formed following PDLSC transplantation. It was determined that PDLSCs produced appreciable levels of vascular endothelial growth factor and basic fibroblast growth factor-2, and additionally, were able to initiate in vitro angiogenesis of ECs comparable to MSC- and SHED-mediated angiogenesis. In vivo cotransplantation of ECs with PDLSCs significantly (>50% increase) enhanced the number of blood vessels formed relative to transplantation of ECs alone. Finally, vessels formed following PDLSC cotransplantation were more mature and less permeable than those formed after transplantation of EC alone. These data demonstrate for the first time that PDLSCs have vascular potential, which could make them a very attractive cell population for utilization in regenerative cell therapies. PMID:24147894

Rapid Copper Acquisition by Developing Murine Mesothelioma: Decreasing Bioavailable Copper Slows Tumor Growth, Normalizes Vessels and Promotes T Cell Infiltration

PubMed Central

Crowe, Andrew; Jackaman, Connie; Beddoes, Katie M.; Ricciardo, Belinda; Nelson, Delia J.

2013-01-01

Copper, an essential trace element acquired through nutrition, is an important co-factor for pro-angiogenic factors including vascular endothelial growth factor (VEGF). Decreasing bioavailable copper has been used as an anti-angiogenic and anti-cancer strategy with promising results. However, the role of copper and its potential as a therapy in mesothelioma is not yet well understood. Therefore, we monitored copper levels in progressing murine mesothelioma tumors and analyzed the effects of lowering bioavailable copper. Copper levels in tumors and organs were assayed using atomic absorption spectrophotometry. Mesothelioma tumors rapidly sequestered copper at early stages of development, the copper was then dispersed throughout growing tumor tissues. These data imply that copper uptake may play an important role in early tumor development. Lowering bioavailable copper using the copper chelators, penicillamine, trientine or tetrathiomolybdate, slowed in vivo mesothelioma growth but did not provide any cures similar to using cisplatin chemotherapy or anti-VEGF receptor antibody therapy. The impact of copper lowering on tumor blood vessels and tumor infiltrating T cells was measured using flow cytometry and confocal microscopy. Copper lowering was associated with reduced tumor vessel diameter, reduced endothelial cell proliferation (reduced Ki67 expression) and lower surface ICAM/CD54 expression implying reduced endothelial cell activation, in a process similar to endothelial normalization. Copper lowering was also associated with a CD4+ T cell infiltrate. In conclusion, these data suggest copper lowering is a potentially useful anti-mesothelioma treatment strategy that slows tumor growth to provide a window of opportunity for inclusion of other treatment modalities to improve patient outcomes. PMID:24013775

Angiogenesis and phenotypic alteration of alveolar capillary endothelium in areas of neoplastic cell spread in primary lung adenocarcinoma.

PubMed

Jin, E; Ghazizadeh, M; Fujiwara, M; Nagashima, M; Shimizu, H; Ohaki, Y; Arai, S; Gomibuchi, M; Takemura, T; Kawanami, O

2001-09-01

Normal alveolar capillary endothelium is quiescent in nature and displays anticoagulant thrombomodulin (TM) on its surface. The cytoplasms of these endothelial cells are ultrastructurally non-fenestrated type, and they barely express von Willebrand factor (vWf). Alveolar fibrosis is accompanied by a capillary endothelium reactive for vWf, and a loss of TM expression. In primary lung adenocarcinoma, neovascularization occurs in association with alveolar fibrosis. In order to study basic factors related to angiogenesis and phenotypic changes of the capillaries located in tumor-bearing alveolar walls, we examined 37 primary lung adenocarcinomas with electron microscopy and confocal laser scanning microscopy with antibodies for TM, vWf, vascular endothelial growth factor (VEGF), and its receptors (KDR and Flt-1), and proliferating markers (Ki-67/proliferating cell nuclear antigen). Tissues microdissected specifically from alveolar walls were used for reverse transcription-polymerase chain reaction (RT-PCR) to assess expressions of mRNA isoforms of VEGF and its receptors. New capillary branching was found by ultrastructural study in the alveolar walls in 12% of the patients. Nuclei of the capillary endothelial cells were reactive for proliferating cell markers. Endothelial fenestrae were developed in 65% of the patients, TM reactivity was lost in the alveolar capillaries, and their cell cytoplasms obtained a reactivity for vWf through a transitional mosaic-like distribution pattern of both antigens. Besides cytoplasmic VEGF expression in neoplastic cells, tumor-bearing alveolar walls showed significant expression of mRNA of VEGF165 and KDR. These findings imply that angiogenesis and phenotypic changes of the alveolar capillaries are closely related to a higher expression of tumor-associated VEGF165 and of KDR in the alveolar walls in primary lung adenocarcinoma.

A Phase II Safety and Efficacy Study of the Vascular Endothelial Growth Factor Receptor Tyrosine Kinase Inhibitor Pazopanib in Patients With Metastatic Urothelial Cancer

PubMed Central

Pili, Roberto; Qin, Rui; Flynn, P.J.; Picus, Joel; Millward, Michael; Ho, Wing Ming; Pitot, Henry; Tan, Winston; Miles, Kiersten M.; Erlichman, Charles; Vaishampayan, Ulka

2013-01-01

Vascular endothelial growth factor (VEGF) is expressed in human bladder tumors. A phase II study was conducted to assess the VEGF inhibitor pazopanib in patients with metastatic, urothelial carcinoma. Nineteen patients with one prior systemic therapy were enrolled. No objective responses were observed and median progression-free survival was 1.9 months. The role of anti-VEGF therapies in urothelial carcinoma remains to be determined. Background Vascular endothelial growth factor (VEGF) is produced by bladder cancer cell lines in vitro and expressed in human bladder tumor tissues. Pazopanib is a vascular endothelial receptor tyrosine kinase inhibitor with anti-angiogenesis and anti-tumor activity in several preclinical models. A 2-stage phase II study was conducted to assess the activity and toxicity profile of pazopanib in patients with metastatic, urothelial carcinoma. Methods Patients with one prior systemic therapy for metastatic urothelial carcinoma were eligible. Patients received pazopanib at a dose of 800 mg orally for a 4-week cycle. Results Nineteen patients were enrolled. No grade 4 or 5 events were experienced. Nine patients experienced 11 grade 3 adverse events. Most common toxicities were anemia, thrombocytopenia, leucopenia, and fatigue. For stage I, none of the first 16 evaluable patients were deemed a success (complete response or partial response) by the Response Evaluation Criteria In Solid Tumors criteria during the first four 4-week cycles of treatment. Median progression-free survival was 1.9 months. This met the futility stopping rule of interim analysis, and therefore the trial was recommended to be permanently closed. Conclusions Pazopanib did not show significant activity in patients with urothelial carcinoma. The role of anti-VEGF therapies in urothelial carcinoma may need further evaluation in rational combination strategies. PMID:23891158

Patterning vascular networks in vivo for tissue engineering applications.

PubMed

Chaturvedi, Ritika R; Stevens, Kelly R; Solorzano, Ricardo D; Schwartz, Robert E; Eyckmans, Jeroen; Baranski, Jan D; Stapleton, Sarah Chase; Bhatia, Sangeeta N; Chen, Christopher S

2015-05-01

The ultimate design of functionally therapeutic engineered tissues and organs will rely on our ability to engineer vasculature that can meet tissue-specific metabolic needs. We recently introduced an approach for patterning the formation of functional spatially organized vascular architectures within engineered tissues in vivo. Here, we now explore the design parameters of this approach and how they impact the vascularization of an engineered tissue construct after implantation. We used micropatterning techniques to organize endothelial cells (ECs) into geometrically defined "cords," which in turn acted as a template after implantation for the guided formation of patterned capillaries integrated with the host tissue. We demonstrated that the diameter of the cords before implantation impacts the location and density of the resultant capillary network. Inclusion of mural cells to the vascularization response appears primarily to impact the dynamics of vascularization. We established that clinically relevant endothelial sources such as induced pluripotent stem cell-derived ECs and human microvascular endothelial cells can drive vascularization within this system. Finally, we demonstrated the ability to control the juxtaposition of parenchyma with perfused vasculature by implanting cords containing a mixture of both a parenchymal cell type (hepatocytes) and ECs. These findings define important characteristics that will ultimately impact the design of vasculature structures that meet tissue-specific needs.

Regulatory mechanisms of anthrax toxin receptor 1-dependent vascular and connective tissue homeostasis.

PubMed

Besschetnova, Tatiana Y; Ichimura, Takaharu; Katebi, Negin; St Croix, Brad; Bonventre, Joseph V; Olsen, Bjorn R

2015-03-01

It is well known that angiogenesis is linked to fibrotic processes in fibroproliferative diseases, but insights into pathophysiological processes are limited, due to lack of understanding of molecular mechanisms controlling endothelial and fibroblastic homeostasis. We demonstrate here that the matrix receptor anthrax toxin receptor 1 (ANTXR1), also known as tumor endothelial marker 8 (TEM8), is an essential component of these mechanisms. Loss of TEM8 function in mice causes reduced synthesis of endothelial basement membrane components and hyperproliferative and leaky blood vessels in skin. In addition, endothelial cell alterations in mutants are almost identical to those of endothelial cells in infantile hemangioma lesions, including activated VEGF receptor signaling in endothelial cells, increased expression of the downstream targets VEGF and CXCL12, and increased numbers of macrophages and mast cells. In contrast, loss of TEM8 in fibroblasts leads to increased rates of synthesis of fiber-forming collagens, resulting in progressive fibrosis in skin and other organs. Compromised interactions between TEM8-deficient endothelial and fibroblastic cells cause dramatic reduction in the activity of the matrix-degrading enzyme MMP2. In addition to insights into mechanisms of connective tissue homeostasis, our data provide molecular explanations for vascular and connective tissue abnormalities in GAPO syndrome, caused by loss-of-function mutations in ANTXR1. Furthermore, the loss of MMP2 activity suggests that fibrotic skin abnormalities in GAPO syndrome are, in part, the consequence of pathophysiological mechanisms underlying syndromes (NAO, Torg and Winchester) with multicentric skin nodulosis and osteolysis caused by homozygous loss-of-function mutations in MMP2. Copyright © 2014 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.

Three-Dimensional Vascular Network Assembly From Diabetic Patient-Derived Induced Pluripotent Stem Cells.

PubMed

Chan, Xin Yi; Black, Rebecca; Dickerman, Kayla; Federico, Joseph; Lévesque, Mathieu; Mumm, Jeff; Gerecht, Sharon

2015-12-01

In diabetics, hyperglycemia results in deficient endothelial progenitors and cells, leading to cardiovascular complications. We aim to engineer 3-dimensional (3D) vascular networks in synthetic hydrogels from type 1 diabetes mellitus (T1D) patient-derived human-induced pluripotent stem cells (hiPSCs), to serve as a transformative autologous vascular therapy for diabetic patients. We validated and optimized an adherent, feeder-free differentiation procedure to derive early vascular cells (EVCs) with high portions of vascular endothelial cadherin-positive cells from hiPSCs. We demonstrate similar differentiation efficiency from hiPSCs derived from healthy donor and patients with T1D. T1D-hiPSC-derived vascular endothelial cadherin-positive cells can mature to functional endothelial cells-expressing mature markers: von Willebrand factor and endothelial nitric oxide synthase are capable of lectin binding and acetylated low-density lipoprotein uptake, form cords in Matrigel and respond to tumor necrosis factor-α. When embedded in engineered hyaluronic acid hydrogels, T1D-EVCs undergo morphogenesis and assemble into 3D networks. When encapsulated in a novel hypoxia-inducible hydrogel, T1D-EVCs respond to low oxygen and form 3D networks. As xenografts, T1D-EVCs incorporate into developing zebrafish vasculature. Using our robust protocol, we can direct efficient differentiation of T1D-hiPSC to EVCs. Early endothelial cells derived from T1D-hiPSC are functional when mature. T1D-EVCs self-assembled into 3D networks when embedded in hyaluronic acid and hypoxia-inducible hydrogels. The capability of T1D-EVCs to assemble into 3D networks in engineered matrices and to respond to a hypoxic microenvironment is a significant advancement for autologous vascular therapy in diabetic patients and has broad importance for tissue engineering. © 2015 American Heart Association, Inc.

Mechanotransduction Effects on Endothelial Cell Proliferation via CD31 and VEGFR2: Implications for Immunomagnetic Separation.

PubMed

Mahajan, Kalpesh D; Nabar, Gauri M; Xue, Wei; Anghelina, Mirela; Moldovan, Nicanor I; Chalmers, Jeffrey J; Winter, Jessica O

2017-09-01

Immunomagnetic separation is used to isolate circulating endothelial cells (ECs) and endothelial progenitor cells (EPCs) for diagnostics and tissue engineering. However, potentially detrimental changes in cell properties have been observed post-separation. Here, the effect of mechanical force, which is naturally applied during immunomagnetic separation, on proliferation of human umbilical vein endothelial cells (HUVEC), kinase insert domain-positive receptor (KDR) cells, and peripheral blood mononuclear cells (PBMCs). Cells are exposed to CD31 or Vascular Endothelial Growth Factor Receptor-2 (VEGFR2) targeted MACSi beads at varying bead to cell ratios and compared to free antibody and unconjugated beads. A vertical magnetic gradient is applied to static 2D cultures, and a magnetic cell sorter is used to analyze cells in dynamic flow. No significant difference in EC proliferation is observed for controls or VEGFR2-targeting beads, whereas CD31-conjugated beads increase proliferation in a dose dependent manner in static 2-D cultures. This effect occurs in the absence of magnetic field, but is more pronounced with magnetic force. After flow sorting, similar increases in proliferation are seen for CD31 targeting beads. Thus, the effects of targeting antibody and magnetic force applied should be considered when designing immunomagnetic separation protocols for ECs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Binding of human endothelium to Ulex europaeus I-coated Dynabeads: application to the isolation of microvascular endothelium.

PubMed

Jackson, C J; Garbett, P K; Nissen, B; Schrieber, L

1990-06-01

A major problem encountered when isolating human microvascular endothelium is the presence of contaminating cells such as fibroblasts that rapidly over-grow the endothelial cells. We describe here a simple, rapid technique for purifying endothelial cells derived from the microvasculature of neonatal foreskin and osteoarthritic and rheumatoid arthritic synovium. This technique is based on the selective binding of the lectin Ulex europaeus I (UEA I) to the endothelial cell surface via fucose residues. Initially UEA I was covalently bound to tosyl-activated super-paramagnetic polystyrene beads (Dynabeads) by incubation for 24 h at room temperature. Cells were isolated by extracting microvascular segments from enzyme-treated (trypsin and Pronase) cubes of tissue. The mixed population of cells obtained were purified by incubating them at 4 degrees C for 10 min with the UEA I-coated Dynabeads. Endothelium bound to the beads whilst contaminating cells were removed by five washes with HBSS using a magnetic particle concentrator. The endothelial cells thus obtained grew to confluence as a cobblestone-like monolayer and expressed von Willebrand factor antigen. The cells were released from the Dynabeads by the competitive binding of fucose (10 min at 4 degrees C). This new method is simple and reproducible and allows pure human microvascular endothelial cells to be cultured within 2 h of obtaining a specimen.

Presence of MUC4 in human milk and at the luminal surfaces of blood vessels.

PubMed

Zhang, Jin; Perez, Aymee; Yasin, Mohammad; Soto, Pedro; Rong, Min; Theodoropoulos, George; Carothers Carraway, Coralie A; Carraway, Kermit L

2005-07-01

MUC4 is a heterodimeric membrane mucin, composed of a mucin subunit ASGP-1 (MUC4alpha) and a transmembrane subunit ASGP-2 (MUC4beta), which has been implicated in the protection of epithelial cell surfaces. Surprisingly, development and characterization of a new monoclonal antibody (mAb), called 1G8, against ASGP-2 demonstrated by immunohistochemistry the presence of MUC4 at the luminal surfaces of blood vessels of both normal tissues and tumors. Muc4 was detected with 1G8 and other Muc4 antibodies in blood vessels from humans, rats and mice. This expression of MUC4 in endothelial cells was confirmed by immunoblotting with 1G8 in human umbilical vein endothelial cells (HUVECs), human iliac artery endothelial cells (HIAECs), and human microvascular endothelial cells (HMVECs). MUC4 could be observed on HUVECs grown on either plastic or Matrigel. Finally, MUC4 expression in the three types of endothelial cell lines was confirmed by reverse transcription-polymerase chain reaction (RT-PCR). These results provide, to our knowledge, the first demonstration of a member of the MUC gene family and membrane mucin in blood vessels. As a luminal surface component, the MUC4 is situated to contribute to the non-adhesive luminal surface and to act as an intrinsic protection and survival factor. (c) 2004 Wiley-Liss, Inc.