1
|
Abstract
Brain injury in the full-term and near-term neonates is a significant cause of mortality and long-term morbidity, resulting in injury patterns distinct from that seen in premature infants and older patients. Therapeutic hypothermia improves long-term outcomes for many of these infants, but there is a continued search for therapies to enhance the plasticity of the newborn brain, resulting in long-term repair. It is likely that a combination strategy utilizing both early and late interventions may have the most benefit, capitalizing on endogenous mechanisms triggered by hypoxia or ischemia. Optimizing care of these critically ill newborns in the acute setting is also vital for improving both short- and long-term outcomes.
Collapse
|
2
|
Koutsoumparis A, Vassili A, Bakopoulou A, Ziouta A, Tsiftsoglou AS. Erythropoietin (rhEPOa) promotes endothelial transdifferentiation of stem cells of the apical papilla (SCAP). Arch Oral Biol 2018; 96:96-103. [PMID: 30205239 DOI: 10.1016/j.archoralbio.2018.09.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 08/10/2018] [Accepted: 09/01/2018] [Indexed: 01/09/2023]
Abstract
OBJECTIVE Mesenchymal stem cells (MSCs) have attracted worldwide attention for their capacity to repair damaged tissue, immunosuppression, ability to differentiate into several cell types and their secretome. Earlier studies have demonstrated their angiogenic potential in vitro and in vivo. However, little is known regarding pro-angiogenic inducers of stable endothelial transdifferentiation of MSCs. Here, we employed human MSCs from the Apical Papilla (SCAP) and investigated whether recombinant human erythropoietin-alpha (rhEPOa) could act as such inducer. DESIGN Cultured SCAP cells were exposed to rhEPOa and assessed for cell growth kinetics, viability and morphology, as well as their capacity to form capillary tubule structures in selected microenvironments. RT-PCR was used to monitor endothelial markers and activation of EPO/EPOR pathway signaling components; while gelatin zymographies to assess activation of MMP-2. RESULTS rhEPOa treatment initially (48 h) accelerated cell proliferation and allowed SCAP to sprout micro-tubular structures. Morphological and biochemical differentiation was accompanied by activation of MMP-2 and upregulation of PECAM-1, VEGFR2, vWF and VE-cadherin/CDH5. SCAP expressed the cognate EPO-R, while rhEPOa-treated SCAP exhibited higher expression of molecules involved in EPO/EPOR pathway (EPOR and JAK2). CONCLUSION rhEPOa is capable of promoting endothelial transdifferentiation of SCAP which may be of clinical value in treating of ischemic disorders.
Collapse
Affiliation(s)
- Anastasios Koutsoumparis
- Laboratory of Pharmacology, School of Pharmaceutical Sciences, Faculty of Health Sciences, Aristotle University of Thessaloniki (A.U.Th), Thessaloniki, GR-54124, Greece
| | - Angelina Vassili
- Laboratory of Pharmacology, School of Pharmaceutical Sciences, Faculty of Health Sciences, Aristotle University of Thessaloniki (A.U.Th), Thessaloniki, GR-54124, Greece
| | - Athina Bakopoulou
- Department of Prosthodontics, School of Dentistry, Faculty of Health Sciences, Aristotle University of Thessaloniki (A.U.Th), Thessaloniki, GR-54124, Greece
| | - Argyro Ziouta
- Laboratory of Pharmacology, School of Pharmaceutical Sciences, Faculty of Health Sciences, Aristotle University of Thessaloniki (A.U.Th), Thessaloniki, GR-54124, Greece
| | - Asterios S Tsiftsoglou
- Laboratory of Pharmacology, School of Pharmaceutical Sciences, Faculty of Health Sciences, Aristotle University of Thessaloniki (A.U.Th), Thessaloniki, GR-54124, Greece.
| |
Collapse
|
3
|
Shi M, Flores B, Li P, Gillings N, McMillan KL, Ye J, Huang LJS, Sidhu SS, Zhong YP, Grompe MT, Streeter PR, Moe OW, Hu MC. Effects of erythropoietin receptor activity on angiogenesis, tubular injury, and fibrosis in acute kidney injury: a "U-shaped" relationship. Am J Physiol Renal Physiol 2017; 314:F501-F516. [PMID: 29187371 DOI: 10.1152/ajprenal.00306.2017] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The erythropoietin receptor (EpoR) is widely expressed but its renoprotective action is unexplored. To examine the role of EpoR in vivo in the kidney, we induced acute kidney injury (AKI) by ischemia-reperfusion in mice with different EpoR bioactivities in the kidney. EpoR bioactivity was reduced by knockin of wild-type human EpoR, which is hypofunctional relative to murine EpoR, and a renal tubule-specific EpoR knockout. These mice had lower EPO/EpoR activity and lower autophagy flux in renal tubules. Upon AKI induction, they exhibited worse renal function and structural damage, more apoptosis at the acute stage (<7 days), and slower recovery with more tubulointerstitial fibrosis at the subacute stage (14 days). In contrast, mice with hyperactive EpoR signaling from knockin of a constitutively active human EpoR had higher autophagic flux, milder kidney damage, and better renal function at the acute stage but, surprisingly, worse tubulointerstitial fibrosis and renal function at the subacute stage. Either excess or deficient EpoR activity in the kidney was associated with abnormal peritubular capillaries and tubular hypoxia, creating a "U-shaped" relationship. The direct effects of EpoR on tubular cells were confirmed in vitro by a hydrogen peroxide model using primary cultured proximal tubule cells with different EpoR activities. In summary, normal erythropoietin (EPO)/EpoR signaling in renal tubules provides defense against renal tubular injury maintains the autophagy-apoptosis balance and peritubular capillary integrity. High and low EPO/EpoR bioactivities both lead to vascular defect, and high EpoR activity overides the tubular protective effects in AKI recovery.
Collapse
Affiliation(s)
- Mingjun Shi
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Brianna Flores
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Peng Li
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center , Dallas, Texas.,Department of Nephrology, Yu-Huang-Ding Hospital, Qingdao University , Yantai, Shandong , People's Republic of China
| | - Nancy Gillings
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Kathryn L McMillan
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Jianfeng Ye
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Lily Jun-Shen Huang
- Department of Cell Biology, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Sachdev S Sidhu
- Banting and Best Department of Medical Research and Department of Molecular Genetics, The Donnelly Centre, University of Toronto , Toronto, Ontario , Canada
| | - Yong-Ping Zhong
- Pape Family Pediatric Research Institute, Department of Pediatrics, Oregon Health and Science University , Portland, Oregon
| | - Maria T Grompe
- Pape Family Pediatric Research Institute, Department of Pediatrics, Oregon Health and Science University , Portland, Oregon
| | - Philip R Streeter
- Pape Family Pediatric Research Institute, Department of Pediatrics, Oregon Health and Science University , Portland, Oregon
| | - Orson W Moe
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center , Dallas, Texas.,Department of Internal Medicine, University of Texas Southwestern Medical Center , Dallas, Texas.,Department of Physiology, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Ming Chang Hu
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center , Dallas, Texas.,Department of Internal Medicine, University of Texas Southwestern Medical Center , Dallas, Texas
| |
Collapse
|
4
|
Nair A, Tang L. Influence of scaffold design on host immune and stem cell responses. Semin Immunol 2017; 29:62-71. [PMID: 28431919 DOI: 10.1016/j.smim.2017.03.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 03/17/2017] [Accepted: 03/24/2017] [Indexed: 12/29/2022]
Abstract
The combined culture of isolated stem cells in tissue engineering scaffolds represents a popular strategy for the regeneration of specialized tissues. Despite of improved outcomes in some tissues, this stem cell-seeded tissue engineering strategy has not led to significant tissue regeneration as expected. The lower-than-expected outcome may be caused by overwhelming immune responses to scaffold materials and poor survival of seeded stem cells following implantation. This review is aimed at summarizing the success and failure of this strategy and also shedding some light on new directions to design scaffolds for promoting regenerative responses via autologous stem cells. The first half of this review summarizes the influence of scaffold physical and chemical properties on immune cell responses to scaffold implants. The second half focuses on the influence of scaffold design to alter immune and stem cell responses for achieving desirable tissue regeneration.
Collapse
Affiliation(s)
- Ashwin Nair
- Joint Biomedical Engineering Program, University of Texas at Arlington, Arlington, TX 76019 and University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390.
| | - Liping Tang
- Joint Biomedical Engineering Program, University of Texas at Arlington, Arlington, TX 76019 and University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390; Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
| |
Collapse
|
5
|
Menuet C, Khemiri H, de la Poëze d'Harambure T, Gestreau C. Polycythemia and high levels of erythropoietin in blood and brain blunt the hypercapnic ventilatory response in adult mice. Am J Physiol Regul Integr Comp Physiol 2016; 310:R979-91. [PMID: 26936784 DOI: 10.1152/ajpregu.00474.2015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 02/26/2016] [Indexed: 11/22/2022]
Abstract
Changes in arterial Po2, Pco2, and pH are the strongest stimuli sensed by peripheral and central chemoreceptors to adjust ventilation to the metabolic demand. Erythropoietin (Epo), the main regulator of red blood cell production, increases the hypoxic ventilatory response, an effect attributed to the presence of Epo receptors in both carotid bodies and key brainstem structures involved in integration of peripheral inputs and control of breathing. However, it is not known whether Epo also has an effect on the hypercapnic chemoreflex. In a first attempt to answer this question, we tested the hypothesis that Epo alters the ventilatory response to increased CO2 levels. Basal ventilation and hypercapnic ventilatory response (HCVR) were recorded from control mice and from two transgenic mouse lines constitutively expressing high levels of human Epo in brain only (Tg21) or in brain and plasma (Tg6), the latter leading to polycythemia. To tease apart the potential effects of polycythemia and levels of plasma Epo in the HCVR, control animals were injected with an Epo analog (Aranesp), and Tg6 mice were treated with the hemolytic agent phenylhydrazine after splenectomy. Ventilatory parameters measured by plethysmography in conscious mice were consistent with data from electrophysiological recordings in anesthetized animals and revealed a blunted HCVR in Tg6 mice. Polycythemia alone and increased levels of plasma Epo blunt the HCVR. In addition, Tg21 mice with an augmented level of cerebral Epo also had a decreased HCVR. We discuss the potential implications of these findings in several physiopathological conditions.
Collapse
|
6
|
Kurtovic S, Ng TT, Gupta A, Arumugaswami V, Chaiboonma KL, Aminzadeh MA, Makkar R, Dafoe DC, Talavera-Adame D. Leptin enhances endothelial cell differentiation and angiogenesis in murine embryonic stem cells. Microvasc Res 2014; 97:65-74. [PMID: 25250519 DOI: 10.1016/j.mvr.2014.09.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 09/08/2014] [Accepted: 09/13/2014] [Indexed: 01/01/2023]
Abstract
The metabolic regulation of leptin and its angiogenic effects have been well characterized in adult mammals. However, the role of leptin in the differentiation of embryonic stem cells (ESCs) to endothelial cells (ECs) has not been characterized. We hypothesized that leptin enhances the generation of ECs derived from ESCs and, in this way, promotes angiogenesis in embryonic vessels. To address this hypothesis, we utilized an in vitro model consisting of murine ESCs-derived embryoid bodies (EBs). Vascular density, EC and angiogenesis markers as well as phosphorylation levels of signal transducer and activator of transcription 3 (pSTAT3) were investigated in leptin-treated EBs and in untreated EBs as controls. ESC-derived ECs were isolated by magnetic sorting based on the expression of platelet endothelial cell adhesion molecule (PECAM-1/CD31). Significant upregulation of EC and angiogenic markers as well as higher vessel density were found in leptin-treated EBs compared to controls. CD31 positive enriched cells derived from leptin-treated EBs had improved proliferation and survival rate and showed higher levels of pSTAT3. These results suggested that leptin promotes EC differentiation and angiogenesis in mouse EBs and that janus tyrosine kinase (JAK)/STAT pathway can play a role in this biological process. Leptin-mediated EC differentiation and angiogenesis in ESCs can be a useful application towards regenerative medicine and tissue engineering.
Collapse
Affiliation(s)
- Silvia Kurtovic
- Comprehensive Transplant Center, Department of Surgery, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
| | - Tina T Ng
- Comprehensive Transplant Center, Department of Surgery, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
| | - Ankur Gupta
- Comprehensive Transplant Center, Department of Surgery, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
| | - Vaithilingaraja Arumugaswami
- Comprehensive Transplant Center, Department of Surgery, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
| | - Kira L Chaiboonma
- Comprehensive Transplant Center, Department of Surgery, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
| | - Mohammad Amin Aminzadeh
- The Heart Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
| | - Raj Makkar
- The Heart Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
| | - Donald C Dafoe
- Comprehensive Transplant Center, Department of Surgery, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA.
| | - Dodanim Talavera-Adame
- Comprehensive Transplant Center, Department of Surgery, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA.
| |
Collapse
|
7
|
Steinritz D, Schmidt A, Simons T, Ibrahim M, Morguet C, Balszuweit F, Thiermann H, Kehe K, Bloch W, Bölck B. Chlorambucil (nitrogen mustard) induced impairment of early vascular endothelial cell migration – Effects of α-linolenic acid and N-acetylcysteine. Chem Biol Interact 2014; 219:143-50. [DOI: 10.1016/j.cbi.2014.05.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 05/16/2014] [Accepted: 05/21/2014] [Indexed: 10/25/2022]
|
8
|
Nair AM, Tsai YT, Shah KM, Shen J, Weng H, Zhou J, Sun X, Saxena R, Borrelli J, Tang L. The effect of erythropoietin on autologous stem cell-mediated bone regeneration. Biomaterials 2013; 34:7364-71. [PMID: 23831188 DOI: 10.1016/j.biomaterials.2013.06.031] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 06/18/2013] [Indexed: 12/20/2022]
Abstract
Mesenchymal stem cells (MSCs) although used for bone tissue engineering are limited by the requirement of isolation and culture prior to transplantation. Our recent studies have shown that biomaterial implants can be engineered to facilitate the recruitment of MSCs. In this study, we explore the ability of these implants to direct the recruitment and the differentiation of MSCs in the setting of a bone defect. We initially determined that both stromal derived factor-1alpha (SDF-1α) and erythropoietin (Epo) prompted different degrees of MSC recruitment. Additionally, we found that Epo and bone morphogenetic protein-2 (BMP-2), but not SDF-1α, triggered the osteogenic differentiation of MSCs in vitro. We then investigated the possibility of directing autologous MSC-mediated bone regeneration using a murine calvaria model. Consistent with our in vitro observations, Epo-releasing scaffolds were found to be more potent in bridging the defect than BMP-2 loaded scaffolds, as determined by computed tomography (CT) scanning, fluorescent imaging and histological analyses. These results demonstrate the tremendous potential, directing the recruitment and differentiation of autologous MSCs has in the field of tissue regeneration.
Collapse
Affiliation(s)
- Ashwin M Nair
- Bioengineering Department, University of Texas Southwestern Medical Center and The University of Texas at Arlington, Arlington, TX 76019, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Cao Y. Erythropoietin in cancer: a dilemma in risk therapy. Trends Endocrinol Metab 2013; 24:190-9. [PMID: 23218687 DOI: 10.1016/j.tem.2012.10.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 10/19/2012] [Accepted: 10/25/2012] [Indexed: 12/19/2022]
Abstract
Erythropoietin (EPO) is a frequently prescribed drug for treatment of cancer-related and chemotherapy-induced anemia in cancer patients. Paradoxically, recent preclinical and clinical studies indicate that EPO could potentially accelerate tumor growth and jeopardize survival in cancer patients. In this review I critically discuss the current knowledge and broad biological functions of EPO in association with tumor growth, invasion, and angiogenesis. The emphasis is focused on discussing the complex interplay between EPO and other tumor-derived factors in angiogenesis, tumor growth, invasion, and metastasis. Understanding the multifarious functions of EPO and its reciprocal relation with other signaling pathways is crucial for developing more effective agents for cancer therapy and for minimizing risks for cancer patients.
Collapse
Affiliation(s)
- Yihai Cao
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, 171 77 Stockholm, Sweden.
| |
Collapse
|
10
|
Gammella E, Leuenberger C, Gassmann M, Ostergaard L. Evidence of synergistic/additive effects of sildenafil and erythropoietin in enhancing survival and migration of hypoxic endothelial cells. Am J Physiol Lung Cell Mol Physiol 2012. [PMID: 23204066 DOI: 10.1152/ajplung.00112.2012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Endothelial cell dysfunction is a common event to several pathologies including pulmonary hypertension, which is often associated with hypoxia. As the endothelium plays an essential role in regulating the dynamic interaction between pulmonary vasodilatation and vasoconstriction, this cell type is fundamental in the development of vascular remodeling and increased vascular resistance. We investigated the protective effects of sildenafil, a phosphodiesterase type 5 inhibitor, given in combination with erythropoietin (Epo), as it has been demonstrated that both drugs have antiapoptotic effects on several cell types. Specifically, we examined the viability and angiogenic properties of rat pulmonary artery endothelial cells upon exposure to either 21% or 1% oxygen, in presence of sildenafil (1 and 100 nM) and Epo (5 and 20 U/ml) alone or in combination (1 nM and 20 U/ml). Cell proliferation and viability were analyzed by Trypan blue staining, MTT assay, and Annexin V/propidium iodide stainings. In all assays, the ability of the combination treatment in improving cell viability was superior to that of either drug alone. The angiogenic properties were studied using a migration and a 3D collagen assay, and the results revealed increases in the migration potential of endothelial cells as well as the ability to form tube-like structures in response to sildenafil and the combination treatment. We therefore conclude that both drugs exert protective effects on endothelial cells on hypoxia and that sildenafil enhances the migratory and angiogenic properties, especially in hypoxic conditions. Furthermore, we present evidence of possible additive or synergistic effects of both drugs.
Collapse
Affiliation(s)
- Elena Gammella
- Department of Human Morphology and Biomedical Sciences, Città Studi, Università degli Studi di Milano, Milan, Italy
| | | | | | | |
Collapse
|
11
|
Erythropoietin is detectable in the ascitic fluid in patients with ovarian tumors. Int J Gynecol Cancer 2012; 22:1470-3. [PMID: 23027039 DOI: 10.1097/igc.0b013e31826fd607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND AND OBJECTIVE Erythropoietin (Epo) is a glycoprotein that stimulates proliferation and migration of human endothelial cells and promotes angiogenesis, which are crucial phenomena in cancer biology. The objective of this study was to investigate whether Epo is detectable in the ascitic fluid of patients with ovarian tumors. PATIENTS AND METHODS We investigated the presence of Epo in the ascitic fluid of 100 women undergoing laparotomy for an ovarian tumor. Epo concentration was quantitated with an immunochemiluminometric assay. RESULTS Ten women had a benign tumor, 13 women had a borderline tumor, and 77 women had ovarian cancer. Epo was detected in all ascitic fluid samples, in similar amounts as in corresponding serum samples. Ascitic fluid Epo concentration did not differ between the 3 study groups (P = 0.081), but in multiple comparisons, ascitic fluid Epo was higher in the women with cancer than in the women with a benign tumor (P = 0.006). Ascitic fluid Epo concentration correlated positively with serum Epo (P < 0.0001) and the volume of ascites (P < 0.0001). In regression analyses, serum Epo, volume of ascites, blood hemoglobin, plasma CA125, tumor stage, tumor grade, and the presence of residual tumor after surgery had no significant independent effect on ascitic fluid Epo. CONCLUSION Considerable amounts of Epo are present in the ascitic fluid of women with ovarian tumors. The origin of Epo in the ascitic fluid of women with ovarian tumors as well as the clinical relevance of our finding remain to be clarified.
Collapse
|
12
|
Choi MS, Shim MR, Oh MY, Kim KW, Lee HC, Yang BC, Chung HK, Kim JH, Lee HT, Hwang IS, Hochi S, Heo YT, Kim NH, Uhm SJ, Park JK, Chang WK, Chung HJ. Proteins associated with reproductive disorders in testes of human erythropoietin gene-harboring transgenic boars. Theriogenology 2012; 78:1020-9. [DOI: 10.1016/j.theriogenology.2012.02.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Revised: 02/07/2012] [Accepted: 02/10/2012] [Indexed: 11/27/2022]
|
13
|
Abstract
Erythropoietin (Epo) is an essential hormone that binds and activates the Epo receptor (EpoR) resident on the surface of erythroid progenitor cells, thereby promoting erythropoiesis. Recombinant human erythropoietin has been used successfully for over 20 years to treat anemia in millions of patients. In addition to erythropoiesis, Epo has also been reported to have other effects, such as tissue protection and promotion of tumor cell growth or survival. This became of significant concern in 2003, when some clinical trials in cancer patients reported increased tumor progression and worse survival outcomes in patients treated with erythropoiesis-stimulating agents (ESAs). One of the potential mechanisms proffered to explain the observed safety issues was that functional EpoR was expressed in tumors and/or endothelial cells, and that ESAs directly stimulated tumor growth and/or antagonized tumor ablative therapies. Since then, numerous groups have performed further research evaluating this potential mechanism with conflicting data and conclusions. Here, we review the biology of endogenous Epo and EpoR expression and function in erythropoiesis, and evaluate the evidence pertaining to the expression of EpoR on normal nonhematopoietic and tumor cells.
Collapse
|
14
|
Aapro M, Jelkmann W, Constantinescu SN, Leyland-Jones B. Effects of erythropoietin receptors and erythropoiesis-stimulating agents on disease progression in cancer. Br J Cancer 2012; 106:1249-58. [PMID: 22395661 PMCID: PMC3314780 DOI: 10.1038/bjc.2012.42] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Erythropoiesis-stimulating agents (ESAs) increase red blood cell (RBC) production in bone marrow by activating the erythropoietin receptor (EpoR) on erythrocytic-progenitor cells. Erythropoiesis-stimulating agents are approved in the United States and Europe for treating anaemia in cancer patients receiving chemotherapy based on randomised, placebo-controlled trials showing that ESAs reduce RBC transfusions. Erythropoiesis-stimulating agent-safety issues include thromboembolic events and concerns regarding whether ESAs increase disease progression and/or mortality in cancer patients. Several trials have reported an association between ESA use and increased disease progression and/or mortality, whereas other trials in the same tumour types have not provided similar findings. This review thoroughly examines available evidence regarding whether ESAs affect disease progression. Both clinical-trial data on ESAs and disease progression, and preclinical data on how ESAs could affect tumour growth are summarised. Preclinical topics include (i) whether tumour cells express EpoR and could be directly stimulated to grow by ESA exposure and (ii) whether endothelial cells express EpoR and could be stimulated by ESA exposure to undergo angiogenesis and indirectly promote tumour growth. Although assessment and definition of disease progression vary across studies, the current clinical data suggest that ESAs may have little effect on disease progression in chemotherapy patients, and preclinical data indicate a direct or indirect effect of ESAs on tumour growth is not strongly supported.
Collapse
Affiliation(s)
- M Aapro
- Institut Multidisciplinaire d' Oncologie, Clinique de Genolier, Route du Muids 3, PO Box 100, Genolier CH-1272, Switzerland.
| | | | | | | |
Collapse
|
15
|
Geudens I, Gerhardt H. Coordinating cell behaviour during blood vessel formation. Development 2011; 138:4569-83. [PMID: 21965610 DOI: 10.1242/dev.062323] [Citation(s) in RCA: 274] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The correct development of blood vessels is crucial for all aspects of tissue growth and physiology in vertebrates. The formation of an elaborate hierarchically branched network of endothelial tubes, through either angiogenesis or vasculogenesis, relies on a series of coordinated morphogenic events, but how individual endothelial cells adopt specific phenotypes and how they coordinate their behaviour during vascular patterning is unclear. Recent progress in our understanding of blood vessel formation has been driven by advanced imaging techniques and detailed analyses that have used a combination of powerful in vitro, in vivo and in silico model systems. Here, we summarise these models and discuss their advantages and disadvantages. We then review the different stages of blood vessel development, highlighting the cellular mechanisms and molecular players involved at each step and focusing on cell specification and coordination within the network.
Collapse
Affiliation(s)
- Ilse Geudens
- Vascular Patterning Laboratory, Vesalius Research Center, VIB, 3000 Leuven, Belgium
| | | |
Collapse
|
16
|
Su KH, Shyue SK, Kou YR, Ching LC, Chiang AN, Yu YB, Chen CY, Pan CC, Lee TS. β Common receptor integrates the erythropoietin signaling in activation of endothelial nitric oxide synthase. J Cell Physiol 2011; 226:3330-9. [DOI: 10.1002/jcp.22678] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
17
|
Grieb G, Simons D, Steinberger H, Vollmar A, Bernhagen J, Pallua N. Improved in vitro cultivation of endothelial progenitor cells as basis for dermal substitutes with enhanced angiogenic capabilities. Langenbecks Arch Surg 2011; 396:1255-62. [DOI: 10.1007/s00423-011-0839-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2011] [Accepted: 08/03/2011] [Indexed: 12/21/2022]
|
18
|
Lombardero M, Kovacs K, Scheithauer BW. Erythropoietin: a hormone with multiple functions. Pathobiology 2011; 78:41-53. [PMID: 21474975 DOI: 10.1159/000322975] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Accepted: 11/22/2010] [Indexed: 12/17/2022] Open
Abstract
Erythropoietin (EPO), the main hemopoietic hormone synthesized by the kidney as well as by the liver in fetal life, is implicated in mammalian erythropoiesis. Production and secretion of EPO and the expression of its receptor (EPO-R) are regulated by tissue oxygenation. EPO and EPO-R, expressed in several tissues, exert pleiotropic activities and have different effects on nonhemopoietic cells. EPO is a cytokine with antiapoptotic activity and plays a potential neuroprotective and cardioprotective role against ischemia. EPO is also involved in angiogenesis, neurogenesis, and the immune response. EPO can prevent metabolic alterations, neuronal and vascular degeneration, and inflammatory cell activation. Consequently, EPO may be of therapeutic use for a variety of disorders. Many tumors express EPO and/or EPO-R, but the action of EPO on tumor cells remains controversial. It has been suggested that EPO promotes the proliferation and survival of cancer cells expressing EPO-R. On the other hand, other reports have concluded that EPO-R plays no role in tumor progression. This review provides a detailed insight into the nonhemopoietic role of EPO and its mechanism(s) of action which may lead to a better understanding of its potential therapeutic value in diverse clinical settings.
Collapse
Affiliation(s)
- Matilde Lombardero
- Department of Anatomy and Animal Production, Faculty of Veterinary Sciences, University of Santiago de Compostela, Lugo, Spain.
| | | | | |
Collapse
|
19
|
Murua A, Herran E, Orive G, Igartua M, Blanco FJ, Pedraz JL, Hernández RM. Design of a composite drug delivery system to prolong functionality of cell-based scaffolds. Int J Pharm 2010; 407:142-50. [PMID: 21094235 DOI: 10.1016/j.ijpharm.2010.11.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 11/11/2010] [Accepted: 11/12/2010] [Indexed: 12/21/2022]
Abstract
Cell encapsulation technology raises hopes in medicine and biotechnology. However, despite important advances in the field in the past three decades, several challenges associated with the biocompatibility are still remaining. In the present study, the effect of a temporary release of an anti-inflammatory agent on co-administered encapsulated allogeneic cells was investigated. The aim was to determine the biocompatibility and efficacy of the approach to prevent the inflammatory response. A composite delivery system comprised of alginate-poly-l-lysine-alginate (APA)-microencapsulated Epo-secreting myoblasts and dexamethasone (DXM)-releasing poly(lactic-co-glycolic acid) (PLGA) microspheres was implanted in the subcutaneous space of Balb/c mice for 45 days. The use of independently co-implanted DXM-loaded PLGA microspheres resulted in an improved functionality of the cell-based graft, evidenced by significantly higher hematocrit levels found in the cell-implanted groups by day 45, which was found to be more pronounced when higher cell-doses (100 μL) were employed. Moreover, no major host reaction was observed upon implantation of the systems, showing good biocompatibility and capability to partially avoid the inflammatory response, probably due to the immunosuppressive effects related to DXM. The findings of this study imply that DXM-loaded PLGA microspheres show promise as release systems to enhance biocompatibility and offer advantage in the development of long-lasting and effective implantable microencapsulated cells by generating a potential immunopriviledged local environment and an effective method to limit the structural ensheathing layer caused by inflammation.
Collapse
Affiliation(s)
- Ainhoa Murua
- NanoBioCel Group, Laboratory of Pharmaceutics, University of the Basque Country, School of Pharmacy, Vitoria-Gasteiz, Spain
| | | | | | | | | | | | | |
Collapse
|
20
|
Davies MH, Stempel AJ, Hubert KE, Powers MR. Altered vascular expression of EphrinB2 and EphB4 in a model of oxygen-induced retinopathy. Dev Dyn 2010; 239:1695-707. [PMID: 20503366 DOI: 10.1002/dvdy.22306] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
EphrinB2 ligands and EphB4 receptors are expressed on endothelial cells (EC) of arteries and veins, respectively, and are essential for vascular development. To understand how these molecules regulate retinal neovascularization (NV), we evaluated their expression in a model of oxygen-induced retinopathy (OIR). EphrinB2 and EphB4 were expressed on arterial and venous trunks, respectively, and on a subset of deep capillary vessels. EphB4 expression was reduced following hyperoxia, while ephrinB2 expression remained unaltered. In addition, a subset of EphB4-positive veins regressed in a caspase-3-dependent manner during hyperoxia. Arteriovenous malformations were also observed with loss of arterial-venous boundaries. Finally, both ephrinB2 and EphB4 were expressed on a subset of neovascular tufts following hyperoxia. These data confirm the contribution of ECs from both venous and arterial origins to the development of retinal NV.
Collapse
Affiliation(s)
- Michael H Davies
- Department of Pediatrics, Oregon Health & Science University, Portland, Oregon, USA
| | | | | | | |
Collapse
|
21
|
Steinritz D, Bölck B, Schwarz J, Balszuweit F, Dühr S, Ibrahim M, Bloch W, Thiermann H, Kehe K. Effect of N-Acetyl Cysteine and α-Linolenic Acid on Sulfur Mustard Caused Impairment of In Vitro Endothelial Tube Formation. Toxicol Sci 2010; 118:521-9. [DOI: 10.1093/toxsci/kfq271] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
|
22
|
Abstract
IMPORTANCE OF THE FIELD Recombinant erythropoietin (rEPO) failed in a recent clinical study to protect from damages induced by ischemic stroke. The lack of acute treatments in ischemic stroke and the promising outcome in numerous preclinical studies in vivo demands a more critical evaluation of the future use of EPO as an acute treatment. AREAS COVERED IN THIS REVIEW The current use and administration of rhEPO and its analogs in animal models and the future use of this cytokine in the treatment of ischemic stroke. WHAT THE READER WILL GAIN In this review the potential reasons for the failure of EPO in the clinical trial are analysed and whether the preclinical trials sufficiently evaluated the true potential of recombinant EPO and its analogs is assessed. Alternative methods for administration of EPO to enhance its potential as a neuroprotective drug in ischemic stroke are discussed. TAKE HOME MESSAGE Failure in clinical trial does not necessarily indicate the lack of therapeutic potential of EPO. This review encourages further investigation of the true potential of EPO as a candidate drug for the treatment of ischemic stroke by improved preclinical experimental design and utilization of alternative administration methods.
Collapse
Affiliation(s)
- Murat Digicaylioglu
- Department of Neurosurgery and Physiology, University of Texas, Health Science Center, 7703 Floyd Curl Drive-7843, San Antonio, TX 78229-3900, USA.
| |
Collapse
|
23
|
Malan D, Wenzel D, Schmidt A, Geisen C, Raible A, Bölck B, Fleischmann BK, Bloch W. Endothelial beta1 integrins regulate sprouting and network formation during vascular development. Development 2010; 137:993-1002. [PMID: 20179098 DOI: 10.1242/dev.045377] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
beta1 integrins are important regulators of vascular differentiation and development, as their endothelial-specific deletion results in embryonic lethality. In the present study, we investigated the molecular mechanisms underlying the prominent vascular abnormalities that occur in the absence of beta1 integrins. Because of the early embryonic lethality of knockout mice, we studied endothelial cell and vessel development in beta1-integrin-deficient murine embryonic stem cells to gain novel insights into the role of beta1 integrins in vasculo-angiogenesis. We found that vessel development was strongly defective in the mutant embryoid bodies (EBs), as only primitive and short sprouts developed from clusters of vascular precursors in beta1 integrin(-/-) EBs, whereas complex network formation of endothelial tubes was observed in wild-type EBs. The vascular defect was due to deficient beta1 integrin expression in endothelial cells, as its endothelial-specific re-expression rescued the phenotype entirely. The mechanism responsible for defective vessel formation was found to be reduced endothelial cell maturation, migration and elongation. Moreover, the lower number of endothelial cells in beta1 integrin(-/-) EBs was due to an increased apoptosis versus proliferation rate. The enhanced apoptosis and proliferation of beta1 integrin(-/-) endothelial cells was related to the elevation of peNOS and pAKT signaling molecules, respectively. Our data demonstrate that endothelial beta1 integrins are determinants of vessel formation and that this effect is mediated via different signaling pathways.
Collapse
Affiliation(s)
- Daniela Malan
- Institute of Physiology I, University of Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany
| | | | | | | | | | | | | | | |
Collapse
|
24
|
Harten SK, Ashcroft M, Maxwell PH. Prolyl hydroxylase domain inhibitors: a route to HIF activation and neuroprotection. Antioxid Redox Signal 2010; 12:459-80. [PMID: 19737089 DOI: 10.1089/ars.2009.2870] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract Ischemic stroke is a major cause of death worldwide, and current therapeutic options are very limited. Preconditioning with an ischemic or hypoxic insult is beneficial in experimental models of ischemic stroke. Ischemia/hypoxia results in activation of numerous transcription factors, including hypoxia inducible factor (HIF), which is a master regulator of oxygen homeostasis. HIF activation induces a diverse range of target genes, encompassing a wide variety of cellular processes; including angiogenesis, energy metabolism, cell survival, radical production/scavenging, iron metabolism, stem cell homing, and differentiation. Inhibition of HIF prolyl hydroxylase domain (PHD) enzymes results in activation of HIF and is likely to mimic, at least in part, the effects of hypoxia preconditioning. A caveat is that not all consequences of HIF activation will be beneficial and some could even be deleterious. Nevertheless, PHD inhibitors may be therapeutically useful in the treatment of stroke. Prototype PHD inhibitors have shown promising results in preclinical models.
Collapse
Affiliation(s)
- Sarah K Harten
- Division of Medicine, Rayne Institute, University College London, University Street, London, United Kingdom.
| | | | | |
Collapse
|
25
|
Induction of nitric oxide by erythropoietin is mediated by the β common receptor and requires interaction with VEGF receptor 2. Blood 2010; 115:896-905. [DOI: 10.1182/blood-2009-04-216432] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Abstract
Vascular endothelial growth factor (VEGF) and erythropoietin (EPO) have profound effects on the endothelium and endothelial progenitor cells (EPCs), which originate from the bone marrow and differentiate into endothelial cells. Both EPO and VEGF have demonstrated an ability to increase the number and performance properties of EPCs. EPC behavior is highly dependent on nitric oxide (NO), and both VEGF and EPO can stimulate intracellular NO. EPO can bind to the homodimeric EPO receptor (EPO-R) and the heterodimeric receptor, EPO-R and the common β receptor (βC-R). Although VEGF has several receptors, VEGF-R2 appears most critical to EPC function. We demonstrate that EPO induction of NO is dependent on the βC-R and VEGF-R2, that VEGF induction of NO is dependent on the expression of the βC-R, and that the βC-R and VEGF-R2 interact. This is the first definitive functional and structural evidence of an interaction between the 2 receptors and has implications for the side effects of EPO.
Collapse
|
26
|
Noghero A, Bussolino F, Gualandris A. Role of the microenvironment in the specification of endothelial progenitors derived from embryonic stem cells. Microvasc Res 2010; 79:178-83. [PMID: 20053368 DOI: 10.1016/j.mvr.2009.12.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Revised: 12/22/2009] [Accepted: 12/25/2009] [Indexed: 01/21/2023]
Abstract
Embryonic stem (ES) cells are pluripotent cells capable of differentiating in all the cell types present in a living organism. They derive from the inner cell mass of blastocysts of different species including humans. Given their unlimited potential, ES cells represent an invaluable resource of different cell types for transplantation and tissue engineering applications. However, in order to accomplish these therapeutic purposes, efficient and controlled in vitro systems of directing ES cell differentiation are mandatory. ES cell differentiation is strongly influenced by physical, chemical and cellular signals provided by the local microenvironment. Understanding the relationships occurring between differentiating cells and surrounding environment is pivotal for a successful ES cells-based therapy. This review describes three different methods of in vitro differentiation of ES cells by outlining the environmental elements required for endothelial fate specification. For each system, the efficiency of endothelial differentiation, the accessibility and the advantages are discussed. The main conclusion that arises from this analysis is that the knowledge of the role played by microenvironment in cell fate determination is essential to control and take advantage of ES cells potential.
Collapse
Affiliation(s)
- Alessio Noghero
- Division of Vascular Biology, Institute for Cancer Research and Treatment (IRCC), 10060 Candiolo, Torino, Italy
| | | | | |
Collapse
|
27
|
Talavera-Adame D, Dafoe DC, Ng TT, Wachsmann-Hogiu S, Castillo-Henkel C, Farkas DL. Enhancement of embryonic stem cell differentiation promoted by avian chorioallantoic membranes. Tissue Eng Part A 2009; 15:3193-200. [PMID: 19364272 DOI: 10.1089/ten.tea.2009.0024] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Avian chorioallantoic membrane (CAM) has been used as a model to explore angiogenesis and to study the microvasculature of transplanted tissues. Because CAM provides a vascular bed, cells can be implanted, and their development can be monitored and modified. We used the CAM model to study the differentiation process of embryoid bodies (EBs) derived from mouse embryonic stem cells (ESCs) influenced by the CAM vascular bed. After EBs were incubated in CAM for 5 days, they underwent further differentiation and became tissue masses (TMs) of different morphologies from those that grew outside CAM. Immunohistochemical analysis of TMs demonstrated tissue-specific markers such as neurofilament light, CD34, collagen IV, cardiac myosin heavy chain (MHC), and cardiotin. Differentiated mouse blood vessels stained with anti-CD31 were found within the TMs, as well as blood vessels stained positive for QH1 and QCPN, markers for quail endothelial cells and perinuclear quail antigen, respectively. Quail erythrocytes inside mouse blood vessels suggested a connection between existing quail vessels and blood vessels growing inside the TMs as a result of EB differentiation. Therefore, CAM could be a suitable model to trigger and study the differentiation of EBs in close interaction with surrogate quail blood vessels.
Collapse
Affiliation(s)
- Dodanim Talavera-Adame
- Comprehensive Transplant Center, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA.
| | | | | | | | | | | |
Collapse
|
28
|
Byts N, Sirén AL. Erythropoietin: a multimodal neuroprotective agent. EXPERIMENTAL & TRANSLATIONAL STROKE MEDICINE 2009; 1:4. [PMID: 20142991 PMCID: PMC2816866 DOI: 10.1186/2040-7378-1-4] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Accepted: 10/21/2009] [Indexed: 05/28/2023]
Abstract
The tissue protective functions of the hematopoietic growth factor erythropoietin (EPO) are independent of its action on erythropoiesis. EPO and its receptors (EPOR) are expressed in multiple brain cells during brain development and upregulated in the adult brain after injury. Peripherally administered EPO crosses the blood-brain barrier and activates in the brain anti-apoptotic, anti-oxidant and anti-inflammatory signaling in neurons, glial and cerebrovascular endothelial cells and stimulates angiogenesis and neurogenesis. These mechanisms underlie its potent tissue protective effects in experimental models of stroke, cerebral hemorrhage, traumatic brain injury, neuroinflammatory and neurodegenerative disease. The preclinical data in support of the use of EPO in brain disease have already been translated to first clinical pilot studies with encouraging results with the use of EPO as a neuroprotective agent.
Collapse
Affiliation(s)
- Nadiya Byts
- University of Würzburg, Department of Neurosurgery, Würzburg, Germany
| | - Anna-Leena Sirén
- University of Würzburg, Department of Neurosurgery, Würzburg, Germany
| |
Collapse
|
29
|
Xue C, Huang Z, Wang J, Dong Y, Zhou X. EphrinB2 and EphB4 expression in pterygia: new insights and preliminary results. CANADIAN JOURNAL OF OPHTHALMOLOGY 2009; 44:185-8. [PMID: 19491953 DOI: 10.3129/i09-005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
OBJECTIVE Pterygium is a growth of fibrovascular tissue onto the cornea, in which the mechanisms of cell proliferation and vascularization are unknown. The ephrin-Eph system, especially ephrinB2 and its receptor EphB4, has been shown to play an important role in tumor angiogenesis. EphrinB2 and EphB4 have also been reportedly involved in the pathogenesis of ocular angiogenesis. This study was designed to investigate the expression of ephrinB2 and its receptor EphB4 in pterygia. DESIGN Experimental study of the expression of ephrinB2 and its receptor EphB4 in pterygia. PARTICIPANTS Twenty-three primary pterygia, 5 recurrent pterygia, and 11 normal conjunctiva were studied. METHODS Immunohistochemistry studies were used to assess ephrinB2 and EphB4 protein expression levels and the tissue distribution in the samples. RESULTS EphrinB2 and EphB4 staining was present at a dense level in the total epithelium of the head portions of both primary and recurrent pterygial specimens, although just in the basal and parabasal layer of the epithelium of most of the normal conjunctivae. CONCLUSIONS EphrinB2 and EphB4 appear to be overexpressed in pterygium, and they may play important roles in its development.
Collapse
Affiliation(s)
- Chunyan Xue
- Department of Ophthalmology, Jinling Hospital, School of Medicine, Nanjing University, China
| | | | | | | | | |
Collapse
|
30
|
Abstract
Embryonic stem cells have become an established tool in vascular biology to study the details of vasculogenesis as well as angiogenesis. There is also a future potential in using embryonic stem cell-derived endothelial cells for therapeutic purposes. It is important to evaluate this model by comparing features of endothelial cells derived from differentiating stem cells and their responsiveness to external stimuli to those of primary endothelial cells and to in vivo models. Through culture of mouse embryonic stem cell we discovered that differentiating stem cells are highly amenable to analyzing biochemical and cell biologic processes that are independent of flow. Endothelial cell function can be studied in the context of mutations or deletions that are embryonically lethal in vivo. Many, if not all, of the features of sprouting angiogenesis in differentiating stem cells closely mimic the in vivo process.
Collapse
Affiliation(s)
- X Li
- Department of Genetics and Pathology, Uppsala University, Rudbeck Laboratory, Dag Hammarskjöldsv. 20, 751 85 Uppsala, Sweden
| | | |
Collapse
|
31
|
Murua A, Orive G, Hernández RM, Pedraz JL. Cryopreservation based on freezing protocols for the long-term storage of microencapsulated myoblasts. Biomaterials 2009; 30:3495-501. [DOI: 10.1016/j.biomaterials.2009.03.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2008] [Accepted: 03/07/2009] [Indexed: 11/25/2022]
|
32
|
Sorg H, Krueger C, Schulz T, Menger MD, Schmitz F, Vollmar B. Effects of erythropoietin in skin wound healing are dose related. FASEB J 2009; 23:3049-58. [DOI: 10.1096/fj.08-109991] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Heiko Sorg
- Institute for Experimental Surgery University of Rostock Rostock Germany
| | - Christian Krueger
- Institute for Experimental Surgery University of Rostock Rostock Germany
| | - Torsten Schulz
- Institute for Experimental Surgery University of Rostock Rostock Germany
| | - Michael D. Menger
- Institute for Clinical and Experimental Surgery University of Saarland Homburg Saar Germany
| | - Frank Schmitz
- Institute of Anatomy University of Saarland Homburg Saar Germany
| | - Brigitte Vollmar
- Institute for Experimental Surgery University of Rostock Rostock Germany
| |
Collapse
|
33
|
Murua A, Orive G, Hernández RM, Pedraz JL. Xenogeneic transplantation of erythropoietin-secreting cells immobilized in microcapsules using transient immunosuppression. J Control Release 2009; 137:174-8. [PMID: 19376171 DOI: 10.1016/j.jconrel.2009.04.009] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Revised: 03/30/2009] [Accepted: 04/09/2009] [Indexed: 12/14/2022]
Abstract
Cell encapsulation technology holds promise for the sustained and controlled delivery of therapeutic proteins such as erythropoietin (Epo). Transplantation of microencapsulated C(2)C(12) myoblasts in syngeneic and allogeneic recipients has been proven to display long-term survival when implanted subcutaneously. However, xenotransplantation approaches may be affected by the rejection of the host and thus may require transient immunosuppression. C(2)C(12) myoblasts genetically engineered to secrete murine Epo (mEpo) were encapsulated in alginate-poly-L-lysine-alginate (APA) microcapsules and implanted subcutaneously in Fischer rats using a transient immunosuppressive FK-506 therapy (2 or 4 weeks) to ameliorate immunoprotection of microcapsules. Rats receiving short-term immunosupression with FK-506 maintained high hematocrit levels for a longer period of time (14 weeks) in comparison with the non-immunosuppressed group. In addition, a significant difference in hematocrit levels was detected by day 65 among rats immunosuppressed for 2 or 4 weeks, corroborating the need of a minimum period of immunosuppression (4 weeks) for this purpose. These results highlight the importance of applying a minimum period (4 weeks) of transient immunosuppression if the host acceptance of xenogeneic implants based on microencapsulated Epo-secreting cells is aimed.
Collapse
Affiliation(s)
- Ainhoa Murua
- Laboratory of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of the Basque Country, 01006, Vitoria-Gasteiz, Spain
| | | | | | | |
Collapse
|
34
|
Di Stefano R, Barsotti MC, Armani C, Santoni T, Lorenzet R, Balbarini A, Celi A. Human peripheral blood endothelial progenitor cells synthesize and express functionally active tissue factor. Thromb Res 2009; 123:925-30. [PMID: 19128821 DOI: 10.1016/j.thromres.2008.10.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 10/07/2008] [Accepted: 10/20/2008] [Indexed: 11/17/2022]
Abstract
INTRODUCTION Endothelial progenitor cells are circulating cells able to home to sites of vascular damage and to contribute to the revascularization of ischemic areas. We evaluated whether endothelial progenitor cells synthesize tissue factor, a procoagulant protein also involved in angiogenesis. MATERIALS AND METHODS Endothelial progenitor cells were obtained from the peripheral blood mononuclear fraction of normal donors and cultured in endothelial medium supplemented with specific growth factors. The procoagulant activity expressed by cells disrupted by freeze-thaw cycles was assessed by a one stage clotting assay. Tissue factor mRNA expression was evaluated by RT-PCR. RESULTS Endothelial progenitor cells do not express procoagulant activity in baseline conditions. However, lipopolysaccharide induces the expression of procoagulant activity. The effect is dose-dependent and reaches statistical significance at 100 ng/mL lipopolysaccharide. Inhibition with an anti-tissue factor antibody and amplification of cDNA with primers based on the tissue factor sequence confirm the identity of this activity with tissue factor. The kinetics of tissue factor expression by endothelial progenitor cells is identical to that of human umbilical vein endothelial cells showing maximal activity within 4 hours, and then decreasing; in contrast, tissue factor expression by mononuclear cells lasts for longer times. Both 5,6-dichloro-beta D-ribofuranosyl-benzimidazole and cycloheximide prevented the expression of procoagulant activity. Stimulation of endothelial progenitor cells with tumor necrosis factor-alpha did not elicit any detectable procoagulant activity. CONCLUSIONS Endothelial progenitor cells can be stimulated by lipopolysaccharide to synthesize tissue factor. This protein might be involved in thrombotic phenomena and might contribute to endothelial progenitor cells related neovascularization.
Collapse
Affiliation(s)
- Rossella Di Stefano
- Cardiovascular Research Laboratory, Cardiac, Thoracic and Vascular Department, University of Pisa, Pisa, Italy.
| | | | | | | | | | | | | |
Collapse
|
35
|
Schmidt A, Bölck B, Jedig M, Steinritz D, Balszuweit F, Kehe K, Bloch W. Nitrogen mustard (Chlorambucil) has a negative influence on early vascular development. Toxicology 2008; 263:32-40. [PMID: 18930110 DOI: 10.1016/j.tox.2008.09.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Revised: 08/27/2008] [Accepted: 09/18/2008] [Indexed: 12/27/2022]
Abstract
The sulphur and nitrogen mustards are strong alkylating agents, which induces inflammations of the skin including blistering right up to ulcerations. Depending on the severity, the wounds may need weeks to heal. In the past it was shown that sulphur mustard has a destructive effect on endothelial precursor cells, which have been shown to play a pivotal role in the wound healing reaction by inducing neovascularisation. However, for these alkylating agents as well as for sulphur mustard nothing is known about their effects on endothelial precursors. Therefore, we investigated and compared the influence of Chlorambucil on proliferation, apoptosis and differentiation of endothelial cells in intact mouse embryoid bodies (EB). EBs were treated at different developmental stages and with different periods of Chlorambucil treatment. It was found that in each developmental stage and under each treatment period's Chlorambucil has an extremely negative effect on the vascularisation with a vessel reduction of around 99%. Of particular importance was the negative effect of treatment around day 3 of the development. On this day we found 377 vessels under control conditions but only 1.6 vessels under 24h treatment of Chlorambucil. At this point in time many endothelial precursors can be found in the EB. Moreover, a negative effect on all stem cells was evident at this point in time, shown by an extreme reduction in EB size with 17.9 mm(2) for the control and only 1.55 mm(2) under Chlorambucil treatment. This negative effect on the vascularisation, on endothelial precursors but also on stem cells in general is of possible importance for impaired wound healing.
Collapse
Affiliation(s)
- Annette Schmidt
- Department of Molecular and Cellular Sport Medicine, German Sport University Cologne, 50933 Cologne, Germany
| | | | | | | | | | | | | |
Collapse
|
36
|
Steingen C, Brenig F, Baumgartner L, Schmidt J, Schmidt A, Bloch W. Characterization of key mechanisms in transmigration and invasion of mesenchymal stem cells. J Mol Cell Cardiol 2008; 44:1072-1084. [PMID: 18462748 DOI: 10.1016/j.yjmcc.2008.03.010] [Citation(s) in RCA: 174] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Revised: 03/05/2008] [Accepted: 03/10/2008] [Indexed: 02/07/2023]
Abstract
For successful systemic stem cell therapy, mesenchymal stem cells (MSCs) must transmigrate across the endothelium and invade their target tissue. To date, most of the underlying mechanisms of transmigration and invasion remain to be elucidated. Improving our knowledge on these core processes might elevate the efficiency of stem cell therapy. Our aim was therefore to characterize key mechanisms involved in transmigration and invasion of MSCs. Co-cultivation experiments infer that MSCs integrate into the endothelial monolayer. However, the time course of adhesion, integration and transmigration depends on the endothelial phenotype and is most effective in venous vessels of the myocardium. Thus, a variable capacity for transmigration exists within the vasculature. Additionally, three-dimensional systems reveal that MSCs penetrate the endothelium and invade the surrounding tissue via plasmic podia. Furthermore, transmigration not only requires the interaction of vascular cell adhesion molecule-1 (VCAM-1) and very late antigen-4 (VLA-4) as verified by blocking experiments, but also triggers the clustering of beta1 integrins. In addition, in situ zymographies infer the activation of gelatinases at sites of MSC invasion into myocardial tissue. As evidenced by ELISA, MSCs secrete matrix metalloproteinase (MMP)-2 but not MMP-9. Finally, media containing additional cytokines accelerate the transmigration. Concluding, key players involved in transmigration and invasion of MSCs are the endothelial phenotype, VCAM-1/VLA-4, beta1 integrins, MMP-2 secretion and cytokines.
Collapse
Affiliation(s)
- Caroline Steingen
- German Sport University Cologne, Institute for Cardiovascular Research and Sport Medicine, Department for Molecular and Cellular Sport Medicine, Cologne, Germany
| | - Florian Brenig
- German Sport University Cologne, Institute for Cardiovascular Research and Sport Medicine, Department for Molecular and Cellular Sport Medicine, Cologne, Germany
| | - Laura Baumgartner
- German Sport University Cologne, Institute for Cardiovascular Research and Sport Medicine, Department for Molecular and Cellular Sport Medicine, Cologne, Germany
| | - Joachim Schmidt
- Dreifaltigkeits-Hospital, Clinic for Orthopedics, Cologne, Germany
| | - Annette Schmidt
- German Sport University Cologne, Institute for Cardiovascular Research and Sport Medicine, Department for Molecular and Cellular Sport Medicine, Cologne, Germany
| | - Wilhelm Bloch
- German Sport University Cologne, Institute for Cardiovascular Research and Sport Medicine, Department for Molecular and Cellular Sport Medicine, Cologne, Germany.
| |
Collapse
|
37
|
Boroujeni MB, Salehnia M, Valojerdi MR, Mowla SJ, Forouzandeh M, Hajizadeh E. Comparison of gene expression profiles in erythroid-like cells derived from mouse embryonic stem cells differentiated in simple and co-culture systems. Am J Hematol 2008; 83:109-15. [PMID: 17712792 DOI: 10.1002/ajh.21037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The feeder layer and the presence of specific growth factors are thought to induce the differentiation of embryonic stem cells (ESCs) in culture. The aim of this study was to evaluate the effect of erythropoietin (EPO) on the differentiation of ESCs into erythroid colonies in simple and co-culture systems. Embryoid bodies were dissociated and replated in semisolid medium in simple culture or in a co-culture system with bone-marrow stromal cells (BMSCs), both in the presence or absence of EPO. Colony assays, benzidine staining, and ultrastructural studies were carried out until day 10 of culture. Expression of the epsilon globin, betaH1 globin, runt-related transcription factor 1 (RUNX1), betamajor globin, and erythropoietin receptor (EPOR) genes was evaluated using semi-quantitative RT-PCR. A comparison with the corresponding controls showed that colony size increased in both systems (P <or= 0.05). The number of benzidine-positive colonies in the co-culture system with EPO (86.6+/-17.86) was significantly different compared to the simple culture system with EPO (43.6+/-4.77; P <or= 0.05). The hemoglobin content of the differentiated cells was visualized in micrographs. Analysis of gene expression showed that all genes except betamajor globin were expressed in the simple culture system, whereas in the co-culture system all genes were expressed. These results confirmed that the presence of EPO in a BMSC co-culture system with ESCs improves the differentiation of ESCs to erythroid colonies. Moreover, evidence of primitive and definitive erythropoiesis was observed in this co-culture system.
Collapse
|
38
|
Lundby C, Hellsten Y, Jensen MBF, Munch AS, Pilegaard H. Erythropoietin receptor in human skeletal muscle and the effects of acute and long-term injections with recombinant human erythropoietin on the skeletal muscle. J Appl Physiol (1985) 2008; 104:1154-60. [PMID: 18218911 DOI: 10.1152/japplphysiol.01211.2007] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The presence and potential physiological role of the erythropoietin receptor (Epo-R) were examined in human skeletal muscle. In this study we demonstrate that Epo-R is present in the endothelium, smooth muscle cells, and in fractions of the sarcolemma of skeletal muscle fibers. To study the potential effects of Epo in human skeletal muscle, two separate studies were conducted: one to study the acute effects of a single Epo injection on skeletal muscle gene expression and plasma hormones and another to study the effects of long-term (14 wk) Epo treatment on skeletal muscle structure. Subjects (n = 11) received a single Epo injection of 15,000 IU (double blinded, cross over, placebo). A single Epo injection reduced myoglobin and increased transferrin receptor and MRF-4 mRNA content within 10 h after injection. Plasma hormones remained unaltered. Capillarization and fiber hypertrophy was studied in subjects (n = 8) who received long-term Epo administration, and muscle biopsies were obtained before and after. Epo treatment did not alter mean fiber area (0.84 +/- 0.2 vs. 0.72 +/- 0.3 mm(2)), capillaries per fiber (4.3 +/- 0.5 vs. 4.4 +/- 1.3), or number of proliferating endothelial cells. In conclusion, the Epo-R is present in the vasculature and myocytes in human skeletal muscle, suggesting a role in both cell types. In accordance, a single injection of Epo regulates myoglobin, MRF-4, and transferrin receptor mRNA levels. However, in contrast to our hypothesis, prolonged Epo administration had no apparent effect on capillarization or muscle fiber hypertrophy.
Collapse
Affiliation(s)
- Carsten Lundby
- Copenhagen Muscle Research Centre, Rigshospitalet, section 7652, Blegdamsvej 3, 2100 Copenhagen Ø, Denmark.
| | | | | | | | | |
Collapse
|
39
|
Efthimiadou A, Pagonopoulou O, Lambropoulou M, Papadopoulos N, Nikolettos NK. ERYTHROPOIETIN ENHANCES ANGIOGENESIS IN AN EXPERIMENTAL CYCLOSPORINE A-INDUCED NEPHROTOXICITY MODEL IN THE RAT. Clin Exp Pharmacol Physiol 2007; 34:866-9. [PMID: 17645631 DOI: 10.1111/j.1440-1681.2007.04670.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
1. Erythropoietin (EPO) is a hormone regulating the proliferation and differentiation of erythroid precursor cells. The hypothesis that haematopoietic and endothelial cells share a common haemanglioblast progenitor among others is based on the finding that both cell lineages express cell surface antigens, such as CD31 and CD34. 2. In the present study, we investigated the angiogenic potential of recombinant human erythropoietin on cyclosporine A (CsA)-induced nephrotoxicity in the rat kidney and compared it with the effect of basic fibroblast growth factor (bFGF), a well-known angiogenic factor. 3. Rats were divided into five groups: A (control), B (EPO treated), C (CsA treated), D (CsA + EPO treated) and E (CsA + bFGF treated). Mouse anti-human CD31 and CD34 antibodies were used to evaluate the kidney vessels present in histological preparations. 4. Glomerular and peritubular capillaries in Group B (EPO) were increased compared with the control (Group A; P < 0.05). Reduction of the same kidney vessels (glomerular and peritubular capillaries) in Group C (CsA; P < 0.05) compared with controls was observed, whereas in Groups D (CsA + EPO treated) and E (CsA + bFGF treated), capillaries were increased compared with Group C (CsA; P < 0.05). 5. Erythropoietin has a significant angiogenic effect in rat kidney with CsA-induced nephrotoxicity, similar to the effect of the other angiogenic factor bFGF.
Collapse
Affiliation(s)
- Anna Efthimiadou
- Department of Physiology, Democritus University of Thrace, Medical School, Alexandroupolis, Greece.
| | | | | | | | | |
Collapse
|
40
|
Jakobsson L, Kreuger J, Claesson-Welsh L. Building blood vessels--stem cell models in vascular biology. ACTA ACUST UNITED AC 2007; 177:751-5. [PMID: 17535968 PMCID: PMC2064276 DOI: 10.1083/jcb.200701146] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Spheroids of differentiating embryonic stem cells, denoted embryoid bodies, constitute a high-quality model for vascular development, particularly well suited for loss-of-function analysis of genes required for early embryogenesis. This review examines vasculogenesis and angiogenesis in murine embryoid bodies and discusses the promise of stem cell–based models for the study of human vascular development.
Collapse
Affiliation(s)
- Lars Jakobsson
- Department of Genetics and Pathology, Uppsala University, SE-751 85 Uppsala, Sweden
| | | | | |
Collapse
|
41
|
Zwezdaryk KJ, Coffelt SB, Figueroa YG, Liu J, Phinney DG, LaMarca HL, Florez L, Morris CB, Hoyle GW, Scandurro AB. Erythropoietin, a hypoxia-regulated factor, elicits a pro-angiogenic program in human mesenchymal stem cells. Exp Hematol 2007; 35:640-52. [PMID: 17379074 DOI: 10.1016/j.exphem.2007.01.044] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2006] [Revised: 01/18/2007] [Accepted: 01/19/2007] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The ability of erythropoietin (EPO) to elicit a pro-angiogenic effect on human mesenchymal stem cells (hMSC) was tested. hMSC are currently under study as therapeutic delivery agents that target tumor vessels. Hypoxia favors the differentiation of hMSC towards a pro-angiogenic program. However, the classical angiogenic factors, vascular endothelial growth factor and basic fibroblast growth factor, are not fully capable of restoring this effect. The hypoxia-regulated factor, EPO, induces angiogenesis in endothelial cells. Here, EPO's pro-angiogenic effect on hMSC was analyzed. METHODS hMSC were tested for EPO receptor expression by western blot, immunofluorescence, and flow cytometry assays. Downstream receptor signaling components JAK and STAT were measured by standard assays. Pro-angiogenesis effects mediated by EPO treatment of hMSC were measured by proliferation, cytokine, or pro-angiogenesis factor secretion, metalloprotease activation, migration, invasion, wound healing, and tubule formation assays. RESULTS hMSC express the cognate EPO receptor and are capable of promoting angiogenesis following EPO treatment in all the angiogenesis assays tested. EPO-treated hMSC proliferate and secrete pro-angiogenesis factors more readily than untreated hMSC. EPO leads to increased hMSC chemotaxis, migration, and activation of matrix metalloprotease-2. This treatment causes greater recruitment of vessels as measured in an in vivo angiogenesis assay. CONCLUSION EPO is capable of eliciting a pro-angiogenesis program in hMSC that instigates secretion of angiogenic factors and the subsequent recruitment of endothelium. This study defines a novel mechanism for tumor cell recruitment of blood vessels that is important to consider in the design of stem cell-based therapies.
Collapse
Affiliation(s)
- Kevin J Zwezdaryk
- Department of Microbiology & Immunology, Tulane University Health Sciences Center, 1430 Tulane Avenue, New Orleans, LA 70112, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Brixius K, Funcke F, Graf C, Bloch W. Endothelial progenitor cells: a new target for the prevention of cardiovascular diseases. ACTA ACUST UNITED AC 2007; 13:705-10. [PMID: 17001208 DOI: 10.1097/01.hjr.0000221862.34662.31] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Endothelial progenitor cells (EPCs) are circulating precursor cells that have been implicated recently in vascular and cardiac regeneration. There is an ongoing discussion on the immunocytological definition of EPCs, based on various surface markers, and currently different cell types are included in the term 'EPC'. This review summarizes the mechanisms that influence function, survival, mobilization and differentiation of EPCs. Furthermore, there are several reports on the clinical use of EPCs for the treatment of cardiovascular diseases. We have focused specifically on the influence of physical activity on EPC function.
Collapse
Affiliation(s)
- Klara Brixius
- Department of Molecular and Cellular Sport Medicine, German Sport University Cologne, Cologne, Germany
| | | | | | | |
Collapse
|
43
|
Andratschke N, Schnaiter A, Schnaitera A, Weber WA, Cai L, Caia L, Schill S, Wiedenmann N, Schwaiger M, Molls M, Nieder C. Preclinical evaluation of erythropoietin administration in a model of radiation-induced kidney dysfunction. Int J Radiat Oncol Biol Phys 2006; 64:1513-8. [PMID: 16580501 DOI: 10.1016/j.ijrobp.2005.11.042] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2005] [Revised: 11/24/2005] [Accepted: 11/30/2005] [Indexed: 10/24/2022]
Abstract
PURPOSE To test whether the clinically available growth factor erythropoietin (EPO) influences radiation-induced normal-tissue damage in a model of kidney dysfunction. METHODS Animal experiments were conducted to test the role of EPO administration in a C3H mouse model of unilateral kidney irradiation with 6, 8, and 10 Gy and to assess the effects of 2 different dose levels of EPO. The kidney function was assessed before radiotherapy, as well as 19, 25, 31, and 37 weeks thereafter by means of (99m)Tc-dimercaptosuccinat scans (static scintigraphy). RESULTS Concomitant EPO administration significantly increased the degree of radiation-induced kidney dysfunction. A dose of 2,000 IU/kg body weight per injection tended to cause more damage than the lower dose of 500 IU/kg. CONCLUSION Administration of growth factors concomitant to radiotherapy might modify the development of kidney dysfunction. Although insulin-like growth factor-1 has previously been shown to protect the kidney, such an effect could not be demonstrated for EPO. The latter agent even increased the development of nephropathy.
Collapse
Affiliation(s)
- Nicolaus Andratschke
- Department of Radiation Oncology, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Werner N, Nickenig G. Clinical and therapeutical implications of EPC biology in atherosclerosis. J Cell Mol Med 2006; 10:318-32. [PMID: 16796802 PMCID: PMC3933124 DOI: 10.1111/j.1582-4934.2006.tb00402.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2006] [Accepted: 05/10/2006] [Indexed: 11/28/2022] Open
Abstract
Bone marrow-derived circulating endothelial progenitor cells have been successfully used to enhance angiogenesis after tissue ischemia. The role of endothelial progenitor cells in endothelial cell homeostasis and their putative role in atherogenesis have been recently investigated. Cardiovascular risk factors negatively influence endothelial progenitor cell number and function while vasculoprotection e.g. by statins, estrogens and physical activity may be partly mediated by progenitor cells. Endogenous mobilization or injection of ex-vivo generated endothelial progenitor cells is associated with an enhanced reendothelialization, an improvement of endothelial function and reduced atherosclerotic burden. In contrast, endothelial progenitor cells may promote plaque angiogenesis in animal models and may negatively influence plaque development and stability. However, in humans with coronary atherosclerotic disease, endothelial progenitor cells are a novel risk predictor for cardiovascular mortality and morbidity. In this review we focus on the role of circulating endothelial progenitor cells in endothelial cell repair mechanisms at the vascular wall and their potentially protective and therapeutic role in atherosclerotic disease.
Collapse
Affiliation(s)
- N Werner
- Medizinische Klinik und Poliklinik II, Universitätsklinikum Bonn, Germany.
| | | |
Collapse
|
45
|
Werner N, Nickenig G. Influence of Cardiovascular Risk Factors on Endothelial Progenitor Cells. Arterioscler Thromb Vasc Biol 2006; 26:257-66. [PMID: 16322535 DOI: 10.1161/01.atv.0000198239.41189.5d] [Citation(s) in RCA: 188] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The ideal way to prevent and cure atherosclerosis and the subsequent end organ damage is to restore and rejuvenate the dysfunctional vasculature and the damaged organs. Various studies have underlined the important role of bone marrow-derived endothelial progenitor cells (EPCs) in vasculogenesis and angiogenesis of ischemic tissue, but only a few studies have concentrated on the role of EPCs in the prevention and therapy of atherosclerosis. Extended endothelial cell damage by cardiovascular risk factors can result in endothelial cell apoptosis with loss of the integrity of the endothelium. The consequences are an increased vascular permeability of the endothelium followed by facilitated migration of monocytes and vascular smooth muscle cell proliferation, resulting in the premature manifestation of an atherosclerotic lesion. A growing body of evidence suggests that circulating EPCs play an important role in endothelial cell regeneration. Systemic transfusion or intrinsic mobilization of EPCs enhances the restoration of the endothelium after focal endothelial denudation, resulting in a diminished neointima formation. In mice with atherosclerotic lesions, bone-marrow-derived stem cells are able to reduce atherosclerotic plaque size. However, various studies have demonstrated that in humans, cardiovascular risk factors impair number and function of EPCs, potentially restricting the therapeutic potential of progenitor cells. The current review focuses on the role of cardiovascular risk factors on endothelial cell apoptosis and EPCs with its pathophysiological consequences for atherogenesis and a regenerative therapy approach and will highlight the role of EPCs as a marker for cardiovascular mortality and morbidity.
Collapse
Affiliation(s)
- Nikos Werner
- Medizinischen Klinik und Poliklinik II, Universitätsklinikum Bonn, Germany
| | | |
Collapse
|