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1
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Yang M, Zhang Y, Li M, Liu X, Darvishi M. The various role of microRNAs in breast cancer angiogenesis, with a special focus on novel miRNA-based delivery strategies. Cancer Cell Int 2023; 23:24. [PMID: 36765409 PMCID: PMC9912632 DOI: 10.1186/s12935-022-02837-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 12/20/2022] [Indexed: 02/12/2023] Open
Abstract
After skin malignancy, breast cancer is the most widely recognized cancer detected in women in the United States. Breast cancer (BCa) can happen in all kinds of people, but it's much more common in women. One in four cases of cancer and one in six deaths due to cancer are related to breast cancer. Angiogenesis is an essential factor in the growth of tumors and metastases in various malignancies. An expanded level of angiogenesis is related to diminished endurance in BCa patients. This function assumes a fundamental part inside the human body, from the beginning phases of life to dangerous malignancy. Various factors, referred to as angiogenic factors, work to make a new capillary. Expanding proof demonstrates that angiogenesis is managed by microRNAs (miRNAs), which are small non-coding RNA with 19-25 nucleotides. MiRNA is a post-transcriptional regulator of gene expression that controls many critical biological processes. Endothelial miRNAs, referred to as angiomiRs, are probably concerned with tumor improvement and angiogenesis via regulation of pro-and anti-angiogenic factors. In this article, we reviewed therapeutic functions of miRNAs in BCa angiogenesis, several novel delivery carriers for miRNA-based therapeutics, as well as CRISPR/Cas9 as a targeted therapy in breast cancer.
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Affiliation(s)
- Min Yang
- College of Traditional Chinese Medicine, Jilin Agricultural Science and Technology University, Jilin, 132101 China
| | - Ying Zhang
- College of Traditional Chinese Medicine, Jilin Agricultural Science and Technology University, Jilin, 132101 China
| | - Min Li
- College of Traditional Chinese Medicine, Jilin Agricultural Science and Technology University, Jilin, 132101 China
| | - Xinglong Liu
- College of Traditional Chinese Medicine, Jilin Agricultural Science and Technology University, Jilin, 132101 China
| | - Mohammad Darvishi
- Infectious Diseases and Tropical Medicine Research Center (IDTMRC), Department of Aerospace and Subaquatic Medicine, AJA University of Medical Sciences, Tehran, Iran
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Hoier B, Olsen K, Hanskov DJA, Jorgensen M, Norup LR, Hellsten Y. Early time course of change in angiogenic proteins in human skeletal muscle and vascular cells with endurance training. Scand J Med Sci Sports 2020; 30:1117-1131. [PMID: 32246511 DOI: 10.1111/sms.13665] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 03/16/2020] [Accepted: 03/24/2020] [Indexed: 11/27/2022]
Abstract
Angiogenic, mitochondrial, and related transcriptional proteins were assessed in human skeletal muscle and isolated vascular cells during the early phase of endurance training. Thigh muscle biopsies were obtained in healthy young subjects, after one acute bout (n = 9) and after 3, 5, 7, and 14 days (n = 9) of cycle ergometer training. Whole muscle homogenates were analyzed for angiogenic, mitochondrial, and regulatory mRNA and protein levels. Angiogenic proteins were determined in muscle-derived endothelial cells and pericytes sorted by fluorescence-activated cell sorting. Acute exercise induced an increase in whole muscle mRNA of peroxisome proliferator-activated receptor gamma coactivator 1α (4.5-fold; P = .002) and vascular endothelial growth factor (VEGF) (2.4-fold; P = .001) at 2 hours post. After 14 days of training, there was an increase in CD31 protein (63%; P = .010) in whole muscle indicating capillary growth. There was also an increase in muscle VEGF receptor 2 (VEGFR2) (1.5-fold; P = .013), in OXPHOS proteins (complex I, II, IV, V; 1.4- to 1.9-fold; P < .05) after 14 days of training and an increase in estrogen-related receptorα protein (1.5-fold; P = .039) at 14 days compared to 5 days of training. Both endothelial cells and pericytes expressed VEGF and other angiogenic factors at the protein level but with a distinctively lower expression of VEGFR2 and thrombospondin-1 (TSP-1) in pericytes. The findings illustrate that initiation of capillary and mitochondrial adaptations occurs within 14 days of training and suggest that sustained changes in angiogenic proteins including VEGF and TSP-1 are moderate in whole muscle and vascular cells.
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Affiliation(s)
- Birgitte Hoier
- Integrative Physiology Section, Cardiovascular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Karina Olsen
- Integrative Physiology Section, Cardiovascular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Dorte J A Hanskov
- Integrative Physiology Section, Cardiovascular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Maria Jorgensen
- Integrative Physiology Section, Cardiovascular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Liselotte R Norup
- Core Facility for Flow Cytometry, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ylva Hellsten
- Integrative Physiology Section, Cardiovascular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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Olfert IM, Baum O, Hellsten Y, Egginton S. Advances and challenges in skeletal muscle angiogenesis. Am J Physiol Heart Circ Physiol 2016; 310:H326-36. [PMID: 26608338 PMCID: PMC4796623 DOI: 10.1152/ajpheart.00635.2015] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 11/18/2015] [Indexed: 12/25/2022]
Abstract
The role of capillaries is to serve as the interface for delivery of oxygen and removal of metabolites to/from tissues. During the past decade there has been a proliferation of studies that have advanced our understanding of angiogenesis, demonstrating that tissue capillary supply is under strict control during health but poorly controlled in disease, resulting in either excessive capillary growth (pathological angiogenesis) or losses in capillarity (rarefaction). Given that skeletal muscle comprises nearly 40% of body mass in humans, skeletal muscle capillary density has a significant impact on metabolism, endocrine function, and locomotion and is tightly regulated at many different levels. Skeletal muscle is also high adaptable and thus one of the few organ systems that can be experimentally manipulated (e.g., by exercise) to study physiological regulation of angiogenesis. This review will focus on the methodological concerns that have arisen in determining skeletal muscle capillarity and highlight the concepts that are reshaping our understanding of the angio-adaptation process. We also summarize selected new findings (physical influences, molecular changes, and ultrastructural rearrangement of capillaries) that identify areas of future research with the greatest potential to expand our understanding of how angiogenesis is normally regulated, and that may also help to better understand conditions of uncontrolled (pathological) angiogenesis.
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Affiliation(s)
- I Mark Olfert
- Center for Cardiovascular and Respiratory Sciences and Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia;
| | - Oliver Baum
- Institute of Anatomy, University of Bern, Bern, Switzerland
| | - Ylva Hellsten
- Integrative Physiology Group, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark; and
| | - Stuart Egginton
- School of Biomedical Sciences, University of Leeds, Leeds, United Kingdom
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Baum O, Gübeli J, Frese S, Torchetti E, Malik C, Odriozola A, Graber F, Hoppeler H, Tschanz SA. Angiogenesis-related ultrastructural changes to capillaries in human skeletal muscle in response to endurance exercise. J Appl Physiol (1985) 2015; 119:1118-26. [PMID: 26384412 DOI: 10.1152/japplphysiol.00594.2015] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 09/15/2015] [Indexed: 11/22/2022] Open
Abstract
The ultrastructure of capillaries in skeletal muscle was morphometrically assessed in vastus lateralis muscle (VL) biopsies taken before and after exercise from 22 participants of two training studies. In study 1 (8 wk of ergometer training), light microscopy revealed capillary-fiber (C/F) ratio (+27%) and capillary density (+16%) to be higher (P ≤ 0.05) in postexercise biopsies than in preexercise biopsies from all 10 participants. In study 2 (6 mo of moderate running), C/F ratio and capillary density were increased (+23% and +20%; respectively, P ≤ 0.05) in VL biopsies from 6 angiogenesis responders (AR) after training, whereas 6 nonangiogenesis responders (NR) showed nonsignificant changes in these structural indicators (-4%/-4%, respectively). Forty capillary profiles per participant were evaluated by point and intersection counting on cross sections after transmission electron microscopy. In study 1, volume density (Vv) and mean arithmetic thickness (T) of endothelial cells (ECs; +19%/+17%, respectively) and pericytes (PCs; +20%/+21%, respectively) were higher (P ≤ 0.05), whereas Vv and T of the pericapillary basement membrane (BM) were -23%/-22% lower (P ≤ 0.05), respectively, in posttraining biopsies. In study 2, exercise-related differences between AR and NR-groups were found for Vv and T of PCs (AR, +26%/+22%, respectively, both P ≤ 0.05; NR, +1%/-3%, respectively, both P > 0.05) and BM (AR, -14%/-13%, respectively, both P ≤ 0.05; NR, -9%/-11%, respectively, P = 0.07/0.10). Vv and T of ECs were higher (AR, +16%/+18%, respectively; NR, +6%/+6%, respectively; all P ≤ 0.05) in both groups. The PC coverage was higher (+13%, P ≤ 0.05) in VL biopsies of individuals in the AR group but nonsignificantly altered (+3%, P > 0.05) in those of the NR group after training. Our study suggests that intensified PC mobilization and BM thinning are related to exercise-induced angiogenesis in human skeletal muscle, whereas training per se induces EC-thickening.
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Affiliation(s)
- Oliver Baum
- Institute of Anatomy, University of Bern, Bern, Switzerland; and
| | - Jennifer Gübeli
- Institute of Anatomy, University of Bern, Bern, Switzerland; and
| | - Sebastian Frese
- Department of Neurology, University Hospital Zurich, Zurich, Switzerland
| | | | - Corinna Malik
- Institute of Anatomy, University of Bern, Bern, Switzerland; and
| | - Adolfo Odriozola
- Institute of Anatomy, University of Bern, Bern, Switzerland; and
| | - Franziska Graber
- Institute of Anatomy, University of Bern, Bern, Switzerland; and
| | - Hans Hoppeler
- Institute of Anatomy, University of Bern, Bern, Switzerland; and
| | - Stefan A Tschanz
- Institute of Anatomy, University of Bern, Bern, Switzerland; and
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5
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Ortiz G, Salica JP, Chuluyan EH, Gallo JE. Diabetic retinopathy: could the alpha-1 antitrypsin be a therapeutic option? Biol Res 2014; 47:58. [PMID: 25723058 PMCID: PMC4335423 DOI: 10.1186/0717-6287-47-58] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 10/13/2014] [Indexed: 02/07/2023] Open
Abstract
Diabetic retinopathy is one of the most important causes of blindness. The underlying mechanisms of this disease include inflammatory changes and remodeling processes of the extracellular-matrix (ECM) leading to pericyte and vascular endothelial cell damage that affects the retinal circulation. In turn, this causes hypoxia leading to release of vascular endothelial growth factor (VEGF) to induce the angiogenesis process. Alpha-1 antitrypsin (AAT) is the most important circulating inhibitor of serine proteases (SERPIN). Its targets include elastase, plasmin, thrombin, trypsin, chymotrypsin, proteinase 3 (PR-3) and plasminogen activator (PAI). AAT modulates the effect of protease-activated receptors (PARs) during inflammatory responses. Plasma levels of AAT can increase 4-fold during acute inflammation then is so-called acute phase protein (APPs). Individuals with low serum levels of AAT could develop disease in lung, liver and pancreas. AAT is involved in extracellular matrix remodeling and inflammation, particularly migration and chemotaxis of neutrophils. It can also suppress nitric oxide (NO) by nitric oxide sintase (NOS) inhibition. AAT binds their targets in an irreversible way resulting in product degradation. The aim of this review is to focus on the points of contact between multiple factors involved in diabetic retinopathy and AAT resembling pleiotropic effects that might be beneficial.
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Affiliation(s)
- Gustavo Ortiz
- Nanomedicine and Vision Group, Facultad de Ciencias Biomédicas, Universidad Austral, Buenos Aires Pilar, Argentina. .,Ciudad Autónoma de Buenos Aires, CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas), Buenos Aires, Argentina.
| | - Juan P Salica
- Nanomedicine and Vision Group, Facultad de Ciencias Biomédicas, Universidad Austral, Buenos Aires Pilar, Argentina.
| | - Eduardo H Chuluyan
- Departamento de Farmacología,Ciudad Autónoma de Buenos Aires, Universidad de Buenos Aires, Buenos Aires, Argentina. .,Ciudad Autónoma de Buenos Aires, CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas), Buenos Aires, Argentina.
| | - Juan E Gallo
- Nanomedicine and Vision Group, Facultad de Ciencias Biomédicas, Universidad Austral, Buenos Aires Pilar, Argentina. .,Ciudad Autónoma de Buenos Aires, CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas), Buenos Aires, Argentina.
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6
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Dore-Duffy P. Pericytes and adaptive angioplasticity: the role of tumor necrosis factor-like weak inducer of apoptosis (TWEAK). Methods Mol Biol 2014; 1135:35-52. [PMID: 24510853 DOI: 10.1007/978-1-4939-0320-7_4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The TNF superfamily member TWEAK has emerged as a pleiotropic cytokine that regulates many cellular functions that include immune/inflammatory activity, angiogenesis, cell proliferation, and fate. TWEAK through its inducible receptor, FGF-inducible molecule 14 (Fn14), can induce both beneficial and deleterious activity that has a profound effect on cell survival. Thus it is highly likely that TWEAK and Fn14 expressed by cells of the neurovascular unit help regulate and maintain vascular and tissue homeostasis. In this chapter we discuss the expression of TWEAK and Fn14 signaling in the cerebral microvascular pericyte. Pericytes are a highly enigmatic population of microvascular cells that are important in regulatory pathways that modulate physiological angiogenesis in response to chronic mild hypoxic stress. A brief introduction will identify the microvascular pericyte. A more detailed discussion of pericyte TWEAK signaling during adaptive angioplasticity will follow.
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Affiliation(s)
- Paula Dore-Duffy
- Division of Neuroimmunology, Department of Neurology, Wayne State University School of Medicine, Detroit, MI, USA
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Hoier B, Prats C, Qvortrup K, Pilegaard H, Bangsbo J, Hellsten Y. Subcellular localization and mechanism of secretion of vascular endothelial growth factor in human skeletal muscle. FASEB J 2013; 27:3496-504. [DOI: 10.1096/fj.12-224618] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Birgitte Hoier
- Department of Nutrition, Exercise, and SportUniversity of CopenhagenCopenhagenDenmark
| | - Clara Prats
- Department of Biomedical SciencesCore Facility of Integrated MicroscopyUniversity of CopenhagenCopenhagenDenmark
| | - Klaus Qvortrup
- Department of Biomedical SciencesCore Facility of Integrated MicroscopyUniversity of CopenhagenCopenhagenDenmark
| | | | - Jens Bangsbo
- Department of Nutrition, Exercise, and SportUniversity of CopenhagenCopenhagenDenmark
| | - Ylva Hellsten
- Department of Nutrition, Exercise, and SportUniversity of CopenhagenCopenhagenDenmark
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8
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Criswell TL, Corona BT, Wang Z, Zhou Y, Niu G, Xu Y, Christ GJ, Soker S. The role of endothelial cells in myofiber differentiation and the vascularization and innervation of bioengineered muscle tissue in vivo. Biomaterials 2012; 34:140-9. [PMID: 23059002 DOI: 10.1016/j.biomaterials.2012.09.045] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2012] [Accepted: 09/20/2012] [Indexed: 12/25/2022]
Abstract
Musculoskeletal disorders are a major cause of disability and effective treatments are currently lacking. Tissue engineering affords the possibility of new therapies utilizing cells and biomaterials for the recovery of muscle volume and function. A major consideration in skeletal muscle engineering is the integration of a functional vasculature within the regenerating tissue. In this study we employed fluorescent cell labels to track the location and differentiation of co-cultured cells in vivo and in vitro. We first utilized a co-culture of fluorescently labeled endothelial cells (ECs) and muscle progenitor cells (MPCs) to investigate the ability of ECs to enhance muscle tissue formation and vascularization in an in vivo model of bioengineered muscle. Scaffolds that had been seeded with both MPCs and ECs showed significantly greater vascularization, tissue formation and enhanced innervation as compared to scaffolds seeded with MPCs alone. Subsequently, we performed in vitro experiments using a 3-cell type system (ECs, MPCs, and pericytes (PCs)) to demonstrate the utility of fluorescent cell labeling for monitoring cell growth and differentiation. The growth and differentiation of individual cell types was determined using live cell fluorescent microscopy demonstrating the utility of fluorescent labels to monitor tissue organization in real time.
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Affiliation(s)
- Tracy L Criswell
- Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA
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9
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Abstract
Peripheral arterial disease (PAD) is a common vascular disease that reduces blood flow capacity to the legs of patients. PAD leads to exercise intolerance that can progress in severity to greatly limit mobility, and in advanced cases leads to frank ischemia with pain at rest. It is estimated that 12 to 15 million people in the United States are diagnosed with PAD, with a much larger population that is undiagnosed. The presence of PAD predicts a 50% to 1500% increase in morbidity and mortality, depending on severity. Treatment of patients with PAD is limited to modification of cardiovascular disease risk factors, pharmacological intervention, surgery, and exercise therapy. Extended exercise programs that involve walking approximately five times per week, at a significant intensity that requires frequent rest periods, are most significant. Preclinical studies and virtually all clinical trials demonstrate the benefits of exercise therapy, including improved walking tolerance, modified inflammatory/hemostatic markers, enhanced vasoresponsiveness, adaptations within the limb (angiogenesis, arteriogenesis, and mitochondrial synthesis) that enhance oxygen delivery and metabolic responses, potentially delayed progression of the disease, enhanced quality of life indices, and extended longevity. A synthesis is provided as to how these adaptations can develop in the context of our current state of knowledge and events known to be orchestrated by exercise. The benefits are so compelling that exercise prescription should be an essential option presented to patients with PAD in the absence of contraindications. Obviously, selecting for a lifestyle pattern that includes enhanced physical activity prior to the advance of PAD limitations is the most desirable and beneficial.
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Affiliation(s)
- Tara L Haas
- Angiogenesis Research Group, Muscle Health Research Centre, Faculty of Health, York University, Toronto, Ontario, Canada
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10
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Knapik A, Hegland N, Calcagni M, Althaus M, Vollmar B, Giovanoli P, Lindenblatt N. Metalloproteinases facilitate connection of wound bed vessels to pre-existing skin graft vasculature. Microvasc Res 2012; 84:16-23. [PMID: 22521453 DOI: 10.1016/j.mvr.2012.04.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 02/16/2012] [Accepted: 04/02/2012] [Indexed: 12/14/2022]
Abstract
BACKGROUND Despite advances in tissue engineering of human skin, the exact revascularization processes remain unclear. Therefore it was the aim of this study to investigate the vascular transformations during engraftment and to identify associated proteolytic factors. METHODS The modified dorsal skinfold chamber with autologous skin grafting was prepared in C57BL/6J mice, and intravital microscopy was performed. The expression of proteases and vascular factors was quantified by immunohistochemistry. RESULTS Reperfusion of the skin graft after 72hours was followed by a temporary angiogenic response of the graft vessels. Wound bed bud formation appeared after 24 to 48hours representing starting points for capillary sprouting. In the reperfused skin graft larger buds developed over several days without transformation into angiogenic sprouts; instead pruning took place. MT1-MMP was detected at sprout tips of in-growing vessels. MMP-2 expression was located at the wound bed/graft connection sites. Pericytes were found to withdraw from the angiogenic vessel in order to facilitate sprouting. CONCLUSIONS Skin graft vasculature responded with temporary angiogenesis to reperfusion, which was pruned after several days and exhibited a different morphology than regular sprouting angiogenesis present within the wound bed. Furthermore we identified MT1-MMP as sprout-tip located protease indicating its potential role as sprout growth facilitator as well as potentially in lysing the existing graft capillaries in order to connect to them. The differences between the wound bed and skin graft angiogenesis may represent a relevant insight into the processes of vascular pruning and may help in the engineering of skin substitutes.
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Affiliation(s)
- Alicia Knapik
- Division of Plastic and Reconstructive Surgery, Department of Surgery, University Hospital Zurich, Raemistrasse 100, 8091 Zürich, Switzerland
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11
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Abstract
(1) Angiogenesis (growth of new capillaries from an existing capillary bed) may result from a mismatch in microvascular supply and metabolic demand (metabolic error signal). Krogh examined the distribution and number of capillaries to explore the correlation between O(2) delivery and O(2) consumption. Subsequently, the heterogeneity in angiogenic response within a muscle has been shown to reflect either differences in fibre type composition or mechanical load. However, local control leads to targetted angiogenesis in the vicinity of glycolytic fibre types following muscle stimulation, or oxidative fibres following endurance training, while heterogeneity of capillary spacing is maintained during ontogenetic growth. (2) Despite limited microscopy resolution and lack of specific markers, Krogh's interest in the structure of the capillary wall paved the way for understanding the mechanisms of capillary growth. Angiogenesis may be influenced by the response of perivascular or stromal cells (fibroblasts, macrophages and pericytes) to altered activity, likely acting as a source for chemical signals modulating capillary growth such as vascular endothelial growth factor. In addition, haemodynamic factors such as shear stress and muscle stretch play a significant role in adaptive remodelling of the microcirculation. (3) Most indices of capillarity are highly dependent on fibre size, resulting in possible bias because of scaling. To examine the consequences of capillary distribution, it is therefore helpful to quantify the area of tissue supplied by individual capillaries. This allows the spatial limitations inherent in most models of tissue oxygenation to be overcome generating an alternative approach to Krogh's tissue cylinder, the capillary domain, to improve descriptions of intracellular oxygen diffusion.
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Affiliation(s)
- S Egginton
- Department of Physiology, University of Birmingham, Birmingham, UK.
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12
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Pfister F, Feng Y, vom Hagen F, Hoffmann S, Molema G, Hillebrands JL, Shani M, Deutsch U, Hammes HP. Pericyte migration: a novel mechanism of pericyte loss in experimental diabetic retinopathy. Diabetes 2008; 57:2495-502. [PMID: 18559662 PMCID: PMC2518502 DOI: 10.2337/db08-0325] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2008] [Accepted: 06/07/2008] [Indexed: 12/14/2022]
Abstract
OBJECTIVE The mechanism underlying pericyte loss during incipient diabetic retinopathy remains controversial. Hyperglycemia induces angiopoietin-2 (Ang-2) transcription, which modulates capillary pericyte coverage. In this study, we assessed loss of pericyte subgroups and the contribution of Ang-2 to pericyte migration. RESEARCH DESIGN AND METHODS Numbers of total pericytes and their subgroups were quantified in retinal digest preparations of spontaneous diabetic XLacZ mice. Pericytes were divided into subgroups according to their localization, their position relative to adjacent endothelial cells, and the expression of LacZ. The contribution of Ang-2 to pericyte migration was assessed in Ang-2 overexpressing (mOpsinhAng2) and deficient (Ang2LacZ) mice. RESULTS Pericyte numbers were reduced by 16% (P < 0.01) in XLacZ mice after 6 months of diabetes. Reduction of pericytes was restricted to pericytes on straight capillaries (relative reduction 27%, P < 0.05) and was predominantly observed in LacZ-positive pericytes (-20%, P < 0.01). Hyperglycemia increased the numbers of migrating pericytes (69%; P < 0.05), of which the relative increase due to diabetes was exclusively in LacZ-negative pericytes, indicating reduced adherence to the capillaries (176%; P < 0.01). Overexpression of Ang-2 in nondiabetic retinas mimicked diabetic pericyte migration of wild-type animals (78%; P < 0.01). Ang-2 deficient mice completely lacked hyperglycemia-induced increase in pericyte migration compared with wild-type littermates. CONCLUSIONS Diabetic pericyte loss is the result of pericyte migration, and this process is modulated by the Ang-Tie system.
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Affiliation(s)
- Frederick Pfister
- 5 Medical Department, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Yuxi Feng
- 5 Medical Department, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Franziska vom Hagen
- 5 Medical Department, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Sigrid Hoffmann
- Medical Research Center, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Grietje Molema
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Jan-Luuk Hillebrands
- Department of Cell Biology, Section Immunology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Moshe Shani
- Institute of Animal Science, The Volcani Center, Bet Dagan, Israel
| | - Urban Deutsch
- Theodor Kocher Institute of Berne, Berne, Switzerland
| | - Hans-Peter Hammes
- 5 Medical Department, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
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13
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Li QF, Rabie ABM. A new approach to control condylar growth by regulating angiogenesis. Arch Oral Biol 2007; 52:1009-17. [PMID: 17640614 DOI: 10.1016/j.archoralbio.2007.05.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2007] [Revised: 05/04/2007] [Accepted: 05/24/2007] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To provide a comprehensive review of the mechanisms of growth of mandibular condyle, the roles of angiogenesis enhancers and inhibitors during endochondral ossification in mandibular condyle and newly developed delivery methods for local gene delivery that may represent strategies to regulate condylar growth. DESIGN Narrative review. RESULTS Angiogenesis is the crucial step in mandibular condylar growth for it regulates the transformation from cartilage to bone. Angiognesis enhancers, especially VEGF and FGF, play important roles in the process of new blood lumen formation and invasion. On the other hand, angiostatin and endostatin inhibit angiogenesis by targeting endothelial cells and several signal cascades. Delivery methods such as liposomes, stem cells and virus vectors have been studied. Recombinant AAV-mediated gene therapy is considered as one of the most promising strategies of condylar growth management. CONCLUSION AAV-mediated gene therapy using VEGF or angiogenesis inhibitor will be a promising way to regulate condylar growth at an early stage.
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Affiliation(s)
- Q F Li
- The Biomedical and Tissue Engineering Group, Department of Orthodontics, Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Hong Kong SAR, China
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14
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Gay IC, Chen S, MacDougall M. Isolation and characterization of multipotent human periodontal ligament stem cells. Orthod Craniofac Res 2007; 10:149-60. [PMID: 17651131 DOI: 10.1111/j.1601-6343.2007.00399.x] [Citation(s) in RCA: 296] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Periodontal ligament (PDL) repair is thought to involve mesenchymal progenitor cells capable of forming fibroblasts, osteoblasts and cementoblasts. However, full characterization of PDL stem cell (SC) populations has not been achieved. OBJECTIVE To isolate and characterize PDLSC and assess their capability to differentiate into bone, cartilage and adipose tissue. METHODS Human PDL cells were stained for STRO-1, FACS sorted and expanded in culture. Human bone marrow SC (BMSC) served as a positive control. PDLSC and BMSC were cultured using standard conditions conducive for osteogenic, chondrogenic and adipogenic differentiation. Osteogenic induction was assayed using alizarine red S staining and expression of alkaline phosphatase (ALP) and bone sialoprotein (BSP). Adipogenic induction was assayed using Oil Red O staining and the expression of PPAR gamma 2 (early) and LPL (late) adipogenic markers. Chondrogenic induction was assayed by collagen type II expression and toluidine blue staining. RESULTS Human PDL tissue contains about 27% STRO-1 positive cells with 3% strongly positive. In osteogenic cultures ALP was observed by day-7 in BMSC and day-14 in PDLSC. BSP expression was detectable by day-7; with more intense staining in PDLSC cultures. In adipogenic cultures both cell populations showed positive Oil Red O staining by day-25 with PPAR gamma 2 and LPL expression. By day-21, both BMSC and PDLSC chondrogenic induced cultures expressed collagen type II and glycosaminoglycans. CONCLUSIONS The PDL contains SC that have the potential to differentiate into osteoblasts, chondrocytes and adipocytes, comparable with previously characterized BMSC. This adult PDLSC population can be utilized for potential therapeutic procedures related to PDL regeneration.
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Affiliation(s)
- I C Gay
- Institute of Oral Health Research, School of Dentistry, University of Alabama at Birmingham, Birmingham, AL 35294-0007, USA
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15
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Schmid SA, Gaumann A, Wondrak M, Eckermann C, Schulte S, Mueller-Klieser W, Wheatley DN, Kunz-Schughart LA. Lactate adversely affects the in vitro formation of endothelial cell tubular structures through the action of TGF-beta1. Exp Cell Res 2007; 313:2531-49. [PMID: 17574548 DOI: 10.1016/j.yexcr.2007.05.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2006] [Revised: 04/02/2007] [Accepted: 05/15/2007] [Indexed: 01/29/2023]
Abstract
When lactate accumulation in a tumor microenvironment reaches an average concentration of 10-20 mM, it tends to reflect a high degree of malignancy. However, the hypothesis that tumor-derived lactate has a number of partially adverse biological effects on malignant and tumor-associated host cells requires further evidence. The present study attempted to evaluate the impact of lactate on the process of angiogenesis, in particular on the formation of tubular structures. The endothelial cell (EC) network in desmoplastic breast tumors is primarily located in areas of reactive fibroblastic stroma. We employed a fibroblast-endothelial cell co-culture model as in vitro angiogenesis system normally producing florid in vitro tubule formation to analyze this situation. In contrast to previous studies, we found that lactate significantly reduces EC network formation in a dose-dependent manner as quantified by semi-automated morphometric analyses following immunohistochemical staining. The decrease in CD31-positive tubular structures and the number of intersections was independent of VEGF supplementation and became more pronounced in the presence of protons. The number of cells, primarily of the fibroblast population, was reduced but cell loss could not be attributed to a decrease in proliferative activity or pronounced apoptotic cell death. Treatment with 10 mM lactate was accompanied by enhanced mRNA expression and release of TGF-beta1, which also shows anti-angiogenic activity in the model. Both TGF-beta1 and lactate induced myofibroblastic differentiation adjacent to the EC tubular structures. The lactate response on the EC network was diminished by TGF-beta1 neutralization, indicating a causal relationship between lactate and TGF-beta1 in the finely tuned processes of vessel formation and maturation which may also occur in vivo within tumor tissue.
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Affiliation(s)
- Stephan A Schmid
- Institute of Pathology, University of Regensburg, Regensburg, Germany.
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16
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Yang DZ, He J, Zhang JC, Wang ZR. Expression of angiostatin cDNA in human gallbladder carcinoma cell line GBC-SD and its effect on endothelial proliferation and growth. World J Gastroenterol 2006; 12:2762-6. [PMID: 16718765 PMCID: PMC4130987 DOI: 10.3748/wjg.v12.i17.2762] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
AIM: To explore the influence of angiostatin up-regulation on the biologic behavior of gallbladder carcinoma cells in vitro and in vitro, and the potential value of angiostatin gene therapy for gallbladder carcinoma.
METHODS: A eukaryotic expression vector of pcDNA3.1(+) containing murine angiostatin was constructed and identified by restriction endonuclease digestion and sequencing. The recombinant vector pcDNA3.1-angiostatin was transfected into human gallbladder carcinoma cell line GBC-SD with Lipofectamine 2000, and paralleled with the vector and mock control. The resistant clone was screened by G418 filtration. Angiostatin transcription and protein expression were examined by RT-PCR, immunofluorescence and Western-blot. The supernatant was collected to treat endothelial cells. Cell proliferation and growth in vitro were observed under microscope.
RESULTS: Murine angiostatin cDNA was successfully cloned into the eukaryotic expression vector pcDNA3.1 (+). After 14 d of transfection and selection with G418, macroscopic resistant cell cloning was formed in the experimental group transfected with pcDNA 3.1(+)-angiostatin and vector control. But untreated cells died in the mock control. Angiostatin was detected by RT-PCR and protein expression was detected in the experimental group by immunofluorescence and Western-blot. Cell proliferation and growth in vitro in the three groups were observed respectively under microscope. No significant difference was observed in the growth speed of GBC-SD cells between groups that were transfected with and without angiostatin. After treatment with supernatant, significant differences were observed in endothelial cell (ECV-304) growth in vitro. The cell proliferation and growth were inhibited.
CONCLUSION: Angiostatin does not directly inhibit human gallbladder carcinoma cell proliferation and growth in vitro, but the secretion of angiostatin inhabits endothelial cell proliferation and growth.
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MESH Headings
- Angiostatins/genetics
- Angiostatins/physiology
- Blotting, Western
- Carcinoma/chemistry
- Carcinoma/genetics
- Carcinoma/pathology
- Cell Line, Tumor
- Cell Proliferation/drug effects
- Cell Survival/drug effects
- Cells, Cultured
- DNA, Complementary/analysis
- DNA, Complementary/genetics
- DNA, Neoplasm/analysis
- DNA, Neoplasm/genetics
- Endothelium, Vascular/cytology
- Endothelium, Vascular/growth & development
- Gallbladder Neoplasms/chemistry
- Gallbladder Neoplasms/genetics
- Gallbladder Neoplasms/pathology
- Gene Expression Regulation, Neoplastic
- Genetic Therapy
- Genetic Vectors/genetics
- Humans
- Immunohistochemistry
- Microscopy, Fluorescence
- Neovascularization, Pathologic
- Reverse Transcriptase Polymerase Chain Reaction
- Transfection
- Up-Regulation
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Affiliation(s)
- Ding-Zhong Yang
- Shannxi Provincial Hospital, Xi'an 710065, Shannxi Province, China.
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17
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Williams JL, Cartland D, Hussain A, Egginton S. A differential role for nitric oxide in two forms of physiological angiogenesis in mouse. J Physiol 2006; 570:445-54. [PMID: 16293647 PMCID: PMC1479877 DOI: 10.1113/jphysiol.2005.095596] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 07/29/2005] [Accepted: 11/10/2005] [Indexed: 11/08/2022] Open
Abstract
NO plays a role in a variety of in vitro models of angiogenesis, although confounding effects of NO on non-endothelial tissues make its role during in vivo angiogenesis unclear. We therefore examined the effects of NO on two physiological models of angiogenesis in mouse skeletal muscle: (1) administration of prazosin (50 mg l-1) thereby increasing blood flow; and (2) muscle overload from surgical ablation of a functional synergist. These models induce angiogenesis via longitudinal splitting and capillary sprouting, respectively. Administration of NG-nitro-L-arginine (L-NNA) abolished the increase in capillary to fibre ratio (C:F) in response to prazosin administration, along with the increases in luminal filopodia and large endothelial vacuoles. L-NNA prevented luminal filopodia and vacuolisation in response to extirpation, but had no effect on abluminal sprouting, and little effect on C:F. Comparison of mice lacking endothelial (eNOS-/-) and neuronal NO synthase (nNOS-/-) showed that longitudinal splitting is eNOS-dependent, and Western blotting demonstrated an increase in eNOS but not inducible NOS (iNOS) expression. These data show that there are two pathways of physiological angiogenesis in skeletal muscle characterised by longitudinal splitting and capillary sprouting, respectively. NO generated by eNOS plays an essential role in splitting but not in sprouting angiogenesis, which has important implications for angiogenic therapies that target NO.
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Affiliation(s)
- James L Williams
- Angiogenesis Research Group, Centre for Cardiovascular Sciences, The University of Birmingham, Birmingham B15 2TT, UK
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18
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Yang DZ, He J, Zhang JC, Wang ZR. Angiostatin inhibits pancreatic cancer cell proliferation and growth in nude mice. World J Gastroenterol 2005; 11:4992-6. [PMID: 16124051 PMCID: PMC4321915 DOI: 10.3748/wjg.v11.i32.4992] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To observe the biologic behavior of pancreatic cancer cells in vitro and in vivo, and to explore the potential value of angiostatin gene therapy for pancreatic cancer.
METHODS: The recombinant vector pcDNA3.1(+)-angiostatin was transfected into human pancreatic cancer cells PC-3 with Lipofectamine 2000, and paralleled with the vector and mock control. Angiostatin transcription and protein expression were determined by immunofluorescence and Western blot. The stable cell line was selected by G418. The supernatant was collected to treat endothelial cells. Cell proliferation and growth in vitro were observed under microscope. Cell growth curves were plotted. The troms-fected or untroms-fected cells overexpressing angiostatin vector were implanted subcutaneously into nude mice. The size of tumors was measured, and microvessel density count (MVD) in tumor tissues was assessed by immunohistochemistry with primary anti-CD34 antibody.
RESULTS: After transfected into PC-3 with Lipofectamine 2000 and selected by G418, macroscopic resistant cell clones were formed in the experimental group transfected with pcDNA 3.1(+)-angiostatin and vector control. But untreated cells died in the mock control. Angiostatin protein expression was detected in the experimental group by immunofluorescence and Western-blot. Cell proliferation and growth in vitro in the three groups were observed respectively under microscope. After treatment with supernatant, significant differences were observed in endothelial cell (ECV-304) growth in vitro. The cell proliferation and growth were inhibited. In nude mice model, markedly inhibited tumorigenesis and slowed tumor expansion were observed in the experimental group as compared to controls, which was parallel to the decreased microvessel density in and around tumor tissue.
CONCLUSION: Angiostatin does not directly inhibit human pancreatic cancer cell proliferation and growth in vitro, but it inhibits endothelial cell growth in vitro. It exerts the anti-tumor functions through antiangiogenesis in a paracrine way in vivo.
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Affiliation(s)
- Ding-Zhong Yang
- Department of Surgery, The First Hospital, Xi'an Jiaotong University, Xi'an 710065, Shaanxi Province, China.
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19
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Manzke E, Katchburian E, Faria FP, Freymüller E. Structural features of forming and developing blood capillaries of the enamel organ of rat molar tooth germs observed by light and electron microscopy. J Morphol 2005; 265:335-42. [PMID: 16094655 DOI: 10.1002/jmor.10363] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The process of vascularization of the enamel organ, a unique epithelial structure, occurs when the tooth germ is fully developed, i.e., at the onset of dentinogenesis. Although the three-dimensional organization of the capillaries has been previously investigated, the structural features underlying the formation of the new capillaries remains poorly understood. Thus, in the hope of better understanding the mechanism of formation of the stellate reticulum capillaries, upper first molar tooth germs of newborn and 3-day-old rats were fixed in glutaraldehyde-formaldehyde and processed for light and electron microscopy. Our results showed that blood capillaries are initially in close proximity to the outer enamel epithelium. Between and intercalated with the capillaries are round/ovoid clusters of cells, some of which are vacuolated, closely apposed to the outer enamel epithelium. The outer enamel epithelium is not a continuous layer, but exhibits gaps between the cells. This suggests that the capillaries penetrate the enamel organ through these gaps, since no invagination of the epithelium was observed. The presence of a cluster of cells containing vacuoles suggests that vasculogenesis is taking place. Images showing loss of the basal lamina, proliferation of endothelial cells, presence of filopodia and lateral sprouting suggests that angiogenesis is also occurring. Thus, neoformation of capillaries of the molar enamel organ of rat seems to occur simultaneously by mechanisms of vasculogenesis and angiogenesis.
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Affiliation(s)
- E Manzke
- Health Sciences Center, UNIVALI, Itajaí, SC, Brazil
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20
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Walsh DA. Angiogenesis in osteoarthritis and spondylosis: successful repair with undesirable outcomes. Curr Opin Rheumatol 2004; 16:609-15. [PMID: 15314503 DOI: 10.1097/01.bor.0000133662.60223.ee] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Osteoarthritis and spondylosis are frequently described as "wear-and-tear" arthritis, apparently contradicting modern management, which focuses on continuing and progressive exercise. Laboratory findings, including the growth of new blood vessels, encourage comparisons with repair processes. This review aims to place recent evidence in the context of previous work emphasizing the dynamic nature of tissues in these conditions. RECENT FINDINGS Synovitis has now become recognized as a common and important feature of osteoarthritis, and vascular growth is enhanced in osteoarthritic synovia when infiltrating macrophages generate angiogenic factors. As the molecular balance between angiogenic and antiangiogenic factors is disturbed, new blood vessels are permitted to grow into normally avascular structures, such as the articular cartilage and intervertebral disc. Angiogenesis is a key factor in new bone formation in osteophytes and at the osteochondral junction, thereby contributing to radiologic disease progression. Innervation of new blood vessels may contribute importantly to chronic pain. SUMMARY Reconceptualizing osteoarthritis and spondylosis as reparative processes provides a pathologic model consistent with current advice to exercise, when exercise facilitates repair. Repair does not, however, lead to normal tissue, and understanding the mechanisms by which changes in joint innervation may occur as a consequence of angiogenesis should lead to novel therapies that alleviate the common symptoms of these highly prevalent conditions.
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Affiliation(s)
- David A Walsh
- Academic Rheumatology, University of Nottingham, UK.
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Abstract
A tumor vasculature is highly unstable and immature, characterized by a high proliferation rate of endothelial cells, hyper-permeability, and chaotic blood flow. The dysfunctional vasculature gives rise to continual plasma leakage and hypoxia in the tumor, resulting in constant on-sets of inflammation and angiogenesis. Tumors are thus likened to wounds that will not heal. The lack of functional mural cells, including pericytes and vascular smooth muscle cells, in tumor vascular structure contributes significantly to the abnormality of tumor vessels. Angiopoietin-1 (Ang1) is a physiological angiogenesis promoter during embryonic development. The function of Ang1 is essential to endothelial cell survival, vascular branching, and pericyte recruitment. However, an increasing amount of experimental data suggest that Ang1-stimulated association of mural cells with endothelial cells lead to stabilization of newly formed blood vessels. This in turn may limit the otherwise continuous angiogenesis in the tumor, and consequently give rise to inhibition of tumor growth. We discuss the enigmatic role of Ang1 in tumor angiogenesis in this review.
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Egginton S, Gerritsen M. Lumen formation: in vivo versus in vitro observations. Microcirculation 2003; 10:45-61. [PMID: 12610663 DOI: 10.1038/sj.mn.7800174] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2002] [Accepted: 09/13/2002] [Indexed: 01/13/2023]
Abstract
Lumen formation must accompany the de novo growth of blood vessels during embryological development, the production of new vessels (vasculogenesis), and the expansion or remodeling of the microcirculation in differentiated tissue (angiogenesis). The debate over lumen origin centers on whether this is an intracellular or intercellular phenomenon, entailing vesicle accretion or loss of endothelial cell (EC) contact, and whether this represents an intrinsic property of ECs or relies on extrinsic signals. In addition, recent in vivo data suggest that a third mechanism, that of longitudinal division, may be used to expand existing capillary networks. Importantly, more than one mechanism of lumen formation may be found in response to a given angiogenic signal. Tubule formation by ECs in a matrix is an increasingly popular form of in vitro angiogenesis assay, and it may offer insights into the mechanisms involved during growth in embryos or under pathological conditions in adults. Crucial to the validity of in vitro preparations is the extent to which tubule assembly and lumen formation mirrors that observed in vivo, although these data cannot elucidate the controls operative during adaptive remodeling of the vascular bed. Similar structures may be observed in vivo and in vitro, and may represent the situation found during angiogenesis and vasculogenesis, respectively. Lumen formation during angiogenesis, and tubule formation during EC culture, require the existence of cell polarity. As tubule formation is not a unique property of ECs, how this is developed is a key area where in vitro studies may extend our understanding of EC biology.
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Affiliation(s)
- Stuart Egginton
- Angiogenesis Research Group, Department of Physiology, University of Birmingham, UK.
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23
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Da Silva-Azevedo L, Baum O, Zakrzewicz A, Pries AR. Vascular endothelial growth factor is expressed in endothelial cells isolated from skeletal muscles of nitric oxide synthase knockout mice during prazosin-induced angiogenesis. Biochem Biophys Res Commun 2002; 297:1270-6. [PMID: 12372425 DOI: 10.1016/s0006-291x(02)02370-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In skeletal muscles, angiogenesis can be induced by increases in wall shear stress. To identify molecules involved in the angiogenic process, a method based on the use of BS-1 lectin-coated magnetic beads was developed to isolate a cellular fraction enriched in microvascular endothelial cells which are directly exposed to wall shear stress. Using such cellular fractions from skeletal muscles of C57 mice in which angiogenesis was induced by administration with the alpha(1)-adrenergic antagonist prazosin, we found the concentration of vascular endothelial growth factor (VEGF) increased in correlation to the duration of the prazosin stimulus. In contrast, the angiopoietin-2/tie-2 system was not changed even after 4days of prazosin treatment. In neuronal nitric oxide synthase (nNOS) knockout mice, the VEGF concentration was also elevated after prazosin treatment but remained almost unchanged in endothelial nitric oxide synthase (eNOS) knockout mice. However, eNOS (and not nNOS) knockout mice expressed higher levels of VEGF under non-stimulated conditions as compared to C57 mice. These results suggest that VEGF produced in endothelial cells is involved in angiogenesis in skeletal muscles of mice responding to the administration of systemic vasodilators. NO derived from eNOS and nNOS may be an important regulator of the angiogenic response in skeletal muscles in vivo.
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Affiliation(s)
- Luis Da Silva-Azevedo
- Department of Physiology, University Clinic Benjamin Franklin, Free University of Berlin, Arnimallee 22 D-14195, Berlin, Germany
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Nadal JA, Scicli GM, Carbini LA, Scicli AG. Angiotensin II stimulates migration of retinal microvascular pericytes: involvement of TGF-beta and PDGF-BB. Am J Physiol Heart Circ Physiol 2002; 282:H739-48. [PMID: 11788425 DOI: 10.1152/ajpheart.00656.2001] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We studied the promigratory effect of angiotensin II (ANG II) on cultured bovine retinal microvascular pericytes. ANG II stimulated migration of pericytes by 86% at 10(-8) M, but this effect was lost at 10(-4) M. Migratory responses were inhibited by the ANG II type 1 (AT(1)) receptor antagonist losartan but not by PD-123319, an AT(2) antagonist. Addition of PD-123319 to the 10(-4) M ANG II dose restored migratory responses. The promigratory effect of ANG II (10(-7) M) was reduced by 59% in absence of gradient. Although ANG II augmented the latent matrix metalloproteinase-2 (MMP-2) activity of the pericyte by 35%, it also doubled tissue inhibitors of MMPs. ANG II-induced migration was not altered by a broad-spectrum MMP inhibitor (GM6001); it was inhibited by ~50% by antibodies against transforming growth factor (TGF)-beta(1/2/3) and was abolished by antibodies against platelet-derived growth factor (PDGF)-BB. We conclude that ANG II induces chemotactic responses on retinal microvascular pericytes acting through the AT(1) receptor. This effect is opposed by the AT(2) receptor. ANG II-induced chemotaxis is mediated by PDGF-BB and involves TGF-beta, but it is independent of MMP activity. It is also independent of vascular endothelial growth factor (VEGF) because VEGF did not stimulate pericyte migration. ANG II can contribute to the regulation of retinal neovascularization by stimulating pericyte migration.
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Affiliation(s)
- Jose A Nadal
- Eye Care Services Research, Henry Ford Health System, Detroit, Michigan 48202-3450, USA
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MILKIEWICZ M, BROWN MD, EGGINTON S, HUDLICKA O. Association between Shear Stress, Angiogenesis, and VEGF in Skeletal MusclesIn Vivo. Microcirculation 2001. [DOI: 10.1111/j.1549-8719.2001.tb00172.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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