51
|
The soluble epoxide hydrolase determines cholesterol homeostasis by regulating AMPK and SREBP activity. Prostaglandins Other Lipid Mediat 2016; 125:30-9. [DOI: 10.1016/j.prostaglandins.2016.05.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 05/02/2016] [Accepted: 05/09/2016] [Indexed: 12/28/2022]
|
52
|
Zippel N, Ding Y, Fleming I. A Modified Aortic Ring Assay to Assess Angiogenic Potential In Vitro. Methods Mol Biol 2016; 1430:205-19. [PMID: 27172956 DOI: 10.1007/978-1-4939-3628-1_14] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Angiogenesis, an integral part of many physiological and pathological processes, is a tightly regulated multistep process. Angiogenesis assays are used to clarify the molecular mechanisms and screen for pharmacological inhibitors. However, most in vitro angiogenesis models measure only one aspect of this process, whereas in vivo assays are complex and difficult to interpret. The ex vivo aortic ring model allows the study of many key features of angiogenesis, such as endothelial activation, branching, and remodeling as well as later steps such as pericyte acquisition. This model can be modified to include genetic manipulation and can be used to assess the pro- or anti-angiogenic effects of compounds in a relatively controlled system.
Collapse
Affiliation(s)
- Nina Zippel
- Institute for Vascular Signalling, Centre for Molecular Medicine, Goethe University, Theodor-Stern-Kai 7, Frankfurt am Main, Frankfurt, D-60590, Germany
| | - Yindi Ding
- Institute for Vascular Signalling, Centre for Molecular Medicine, Goethe University, Theodor-Stern-Kai 7, Frankfurt am Main, Frankfurt, D-60590, Germany
| | - Ingrid Fleming
- Institute for Vascular Signalling, Centre for Molecular Medicine, Goethe University, Theodor-Stern-Kai 7, Frankfurt am Main, Frankfurt, D-60590, Germany.
| |
Collapse
|
53
|
Abstract
The developing central nervous system (CNS) is vascularised through the angiogenic invasion of blood vessels from a perineural vascular plexus, followed by continued sprouting and remodelling until a hierarchical vascular network is formed. Remarkably, vascularisation occurs without perturbing the intricate architecture of the neurogenic niches or the emerging neural networks. We discuss the mouse hindbrain, forebrain and retina as widely used models to study developmental angiogenesis in the mammalian CNS and provide an overview of key cellular and molecular mechanisms regulating the vascularisation of these organs. CNS vascularisation is initiated during embryonic development. CNS vascularisation is studied in the mouse forebrain, hindbrain and retina models. Neuroglial cells interact with endothelial cells to promote angiogenesis. Neuroglial cells produce growth factors and matrix cues to pattern vessels.
Collapse
|
54
|
Frömel T, Fleming I. Whatever happened to the epoxyeicosatrienoic Acid-like endothelium-derived hyperpolarizing factor? The identification of novel classes of lipid mediators and their role in vascular homeostasis. Antioxid Redox Signal 2015; 22:1273-92. [PMID: 25330284 DOI: 10.1089/ars.2014.6150] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
SIGNIFICANCE Cytochrome P450 (CYP) epoxygenases metabolize arachidonic acid (AA) to generate epoxyeicosatrienoic acids (EETs). The latter are biologically active and reported to act as an endothelium-derived hyperpolarizing factor as well as to affect angiogenic and inflammatory signaling pathways. RECENT ADVANCES In addition to AA, the CYP enzymes also metabolize the ω-3 polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid and docosahexaenoic acid to generate bioactive lipid epoxide mediators. The latter can be more potent than the EETs, but their actions are under investigated. The ω3-epoxides, like the EETs, are metabolized by the soluble epoxide hydrolase (sEH) to corresponding diols, and epoxide hydrolase inhibition increases epoxide levels and demonstrates anti-hypertensive as well as anti-inflammatory effects. CRITICAL ISSUES It seems that the overall consequences of CYP activation largely depend on enzyme substrate preference and the endogenous ω-3/ω-6 PUFA ratio. FUTURE DIRECTIONS More studies combining PUFA profiling with cell signaling and disease studies are required to determine the spectrum of molecular pathways affected by the different ω-6 and ω-3 PUFA epoxides and diols. Such information may help improve dietary studies aimed at promoting health via ω-3 PUFA supplementation and/or sEH inhibition.
Collapse
Affiliation(s)
- Timo Frömel
- Institute for Vascular Signalling, Centre for Molecular Medicine, Goethe University , Frankfurt am Main, Frankfurt, Germany
| | | |
Collapse
|
55
|
Tan SM, Deliyanti D, Figgett WA, Talia DM, de Haan JB, Wilkinson-Berka JL. Ebselen by modulating oxidative stress improves hypoxia-induced macroglial Müller cell and vascular injury in the retina. Exp Eye Res 2015; 136:1-8. [PMID: 25912997 DOI: 10.1016/j.exer.2015.04.015] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 03/31/2015] [Accepted: 04/22/2015] [Indexed: 01/08/2023]
Abstract
Oxidative stress is an important contributor to glial and vascular cell damage in ischemic retinopathies. We hypothesized that ebselen via its ability to reduce reactive oxygen species (ROS) and augment nuclear factor-like 2 (Nrf2) anti-oxidants would attenuate hypoxia-induced damage to macroglial Müller cells and also lessen retinal vasculopathy. Primary cultures of rat Müller cells were exposed to normoxia (21% O2), hypoxia (0.5% O2) and ebselen (2.5 μM) for up to 72 h. Oxygen-induced retinopathy (OIR) was induced in C57BL/6J mice while control mice were housed in room air. Mice received vehicle (saline, 5% dimethyl sulfoxide) or ebselen (10 mg/kg) each day between postnatal days 6-18. In cultured Müller cells, flow cytometry for dihydroethidium revealed that ebselen reduced the hypoxia-induced increase in ROS levels, whilst increasing the expression of Nrf2-regulated anti-oxidant genes, heme oxygenase 1, glutathione peroxidase-1, NAD(P)H dehydrogenase quinone oxidoreductase 1 and glutamate-cysteine ligase. Moreover, in Müller cells, ebselen reduced the hypoxia-induced increase in protein levels of pro-angiogenic and pro-inflammatory factors including vascular endothelial growth factor, interleukin-6, monocyte chemoattractant-protein 1 and intercellular adhesion molecule-1, and the mRNA levels of glial fibrillary acidic protein (GFAP), a marker of Müller cell injury. Ebselen improved OIR by attenuating capillary vaso-obliteration and neovascularization and a concomitant reduction in Müller cell gliosis and GFAP. We conclude that ebselen protects against hypoxia-induced injury of retinal Müller cells and the microvasculature, which is linked to its ability to reduce oxidative stress, vascular damaging factors and inflammation. Agents such as ebselen may be potential treatments for retinopathies that feature oxidative stress-mediated damage to glia and the microvasculature.
Collapse
Affiliation(s)
- Sih Min Tan
- Oxidative Stress Laboratory, Diabetic Complications Division, Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Devy Deliyanti
- Department of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - William A Figgett
- Department of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - Dean M Talia
- Department of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - Judy B de Haan
- Oxidative Stress Laboratory, Diabetic Complications Division, Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia; Department of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, Victoria, Australia.
| | - Jennifer L Wilkinson-Berka
- Oxidative Stress Laboratory, Diabetic Complications Division, Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia; Department of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, Victoria, Australia
| |
Collapse
|
56
|
Shaikh SR, Wassall SR, Brown DA, Kosaraju R. N-3 Polyunsaturated Fatty Acids, Lipid Microclusters, and Vitamin E. CURRENT TOPICS IN MEMBRANES 2015; 75:209-31. [PMID: 26015284 DOI: 10.1016/bs.ctm.2015.03.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Increased consumption of long-chain marine n-3 polyunsaturated fatty acids (PUFA) has potential health benefits for the general population and for select clinical populations. However, several key limitations remain in making adequate dietary recommendations on n-3 PUFAs in addition to translating the fatty acids into clinical trials for select diseases. One major constraint is an incomplete understanding of the underlying mechanisms of action of n-3 PUFAs. In this review, we highlight studies to show n-3 PUFA acyl chains reorganize the molecular architecture of plasma membrane sphingolipid-cholesterol-enriched lipid rafts and potentially sphingolipid-rich cholesterol-free domains and cardiolipin-protein scaffolds in the inner mitochondrial membrane. We also discuss the possibility that the effects of n-3 PUFAs on membrane organization could be regulated by the presence of vitamin E (α-tocopherol), which is necessary to protect highly unsaturated acyl chains from oxidation. Finally, we propose the integrated hypothesis, based predominately on studies in lymphocytes, cancer cells, and model membranes, that the mechanism by which n-3 PUFAs disrupt signaling microclusters is highly dependent on the type of lipid species that incorporate n-3 PUFA acyl chains. The current evidence suggests that n-3 PUFA acyl chains disrupt lipid raft formation by incorporating primarily into phosphatidylethanolamines but can also incorporate into other lipid species of the lipidome.
Collapse
Affiliation(s)
- Saame Raza Shaikh
- Department of Biochemistry & Molecular Biology, East Carolina University, Greenville, NC, USA; Department of Microbiology and Immunology, East Carolina University, Greenville, NC, USA; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, USA
| | - Stephen R Wassall
- Department of Physics, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
| | - David A Brown
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, USA; Department of Physiology, East Carolina University, Greenville, NC, USA
| | - Rasagna Kosaraju
- Department of Biochemistry & Molecular Biology, East Carolina University, Greenville, NC, USA; East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, USA
| |
Collapse
|
57
|
Laurenzana A, Fibbi G, Chillà A, Margheri G, Del Rosso T, Rovida E, Del Rosso M, Margheri F. Lipid rafts: integrated platforms for vascular organization offering therapeutic opportunities. Cell Mol Life Sci 2015; 72:1537-57. [PMID: 25552244 PMCID: PMC11113367 DOI: 10.1007/s00018-014-1814-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 12/12/2014] [Accepted: 12/19/2014] [Indexed: 02/07/2023]
Abstract
Research on the nanoscale membrane structures known as lipid rafts is relevant to the fields of cancer biology, inflammation and ischaemia. Lipid rafts recruit molecules critical to signalling and regulation of the invasion process in malignant cells, the leukocytes that provide immunity in inflammation and the endothelial cells that build blood and lymphatic vessels, as well as the patterning of neural networks. As angiogenesis is a common denominator, regulation of receptors and signalling molecules critical to angiogenesis is central to the design of new approaches aimed at reducing, promoting or normalizing the angiogenic process. The goal of this review is to highlight some of the key issues that indicate the involvement of endothelial cell lipid rafts at each step of so-called 'sprouting angiogenesis', from stimulation of the vascular endothelial growth factor to the choice of tip cells, activation of migratory and invasion pathways, recruitment of molecules that guide axons in vascular patterning and maturation of blood vessels. Finally, the review addresses opportunities for future studies to define how these lipid domains (and their constituents) may be manipulated to stimulate the so-called 'normalization' of vascular networks within tumors, and be identified as the main target, enabling the development of more efficient chemotherapeutics and cancer immunotherapies.
Collapse
Affiliation(s)
- Anna Laurenzana
- Section of Experimental Pathology and Oncology, Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale GB Morgagni 50, 50134 Florence, Italy
| | - Gabriella Fibbi
- Section of Experimental Pathology and Oncology, Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale GB Morgagni 50, 50134 Florence, Italy
| | - Anastasia Chillà
- Section of Experimental Pathology and Oncology, Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale GB Morgagni 50, 50134 Florence, Italy
| | - Giancarlo Margheri
- Institute of Complex Systems (ISC), Consiglio Nazionale delle Ricerche (CNR), Florence, Italy
| | - Tommaso Del Rosso
- Department of Physics, Pontificia Universidade Catolica do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Elisabetta Rovida
- Section of Experimental Pathology and Oncology, Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale GB Morgagni 50, 50134 Florence, Italy
| | - Mario Del Rosso
- Section of Experimental Pathology and Oncology, Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale GB Morgagni 50, 50134 Florence, Italy
- Istituto Toscano Tumori, Florence, Italy
| | - Francesca Margheri
- Section of Experimental Pathology and Oncology, Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale GB Morgagni 50, 50134 Florence, Italy
| |
Collapse
|
58
|
|
59
|
Fleming I. The Pharmacology of the Cytochrome P450 Epoxygenase/Soluble Epoxide Hydrolase Axis in the Vasculature and Cardiovascular Disease. Pharmacol Rev 2014; 66:1106-40. [DOI: 10.1124/pr.113.007781] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
|
60
|
Wang W, Zhu J, Lyu F, Panigrahy D, Ferrara KW, Hammock B, Zhang G. ω-3 polyunsaturated fatty acids-derived lipid metabolites on angiogenesis, inflammation and cancer. Prostaglandins Other Lipid Mediat 2014; 113-115:13-20. [PMID: 25019221 DOI: 10.1016/j.prostaglandins.2014.07.002] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 06/19/2014] [Accepted: 07/03/2014] [Indexed: 12/29/2022]
Abstract
Epidemiological and pre-clinical studies support the anti-tumor effects of ω-3 PUFAs; however, the results from human trials are mixed, making it difficult to provide dietary guidelines or recommendations of ω-3 PUFAs for disease prevention or treatment. Understanding the molecular mechanisms by which ω-3 PUFAs inhibit cancer could lead to better nutritional paradigms and human trials to clarify their health effects. The ω-3 PUFAs exert their biological activities mainly through the formation of bioactive lipid metabolites. Here we discuss the biology of cyclooxygenase, lipoxygenase and cytochrome P450 enzymes-derived ω-3-series lipid metabolites on angiogenesis, inflammation and cancer.
Collapse
Affiliation(s)
- Weicang Wang
- Department of Food Science, University of Massachusetts-Amherst, Amherst, MA 01003, United States
| | - Julia Zhu
- Department of Food Science, University of Massachusetts-Amherst, Amherst, MA 01003, United States
| | - Fei Lyu
- Department of Food Science, University of Massachusetts-Amherst, Amherst, MA 01003, United States
| | - Dipak Panigrahy
- Center for Vascular Biology Research and Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, United States
| | - Katherine W Ferrara
- Department of Biomedical Engineering, University of California, Davis, CA 95616, United States
| | - Bruce Hammock
- Department of Entomology and Comprehensive Cancer Center, University of California, Davis, CA 95616, United States.
| | - Guodong Zhang
- Department of Food Science, University of Massachusetts-Amherst, Amherst, MA 01003, United States.
| |
Collapse
|
61
|
Capozzi ME, McCollum GW, Penn JS. The role of cytochrome P450 epoxygenases in retinal angiogenesis. Invest Ophthalmol Vis Sci 2014; 55:4253-60. [PMID: 24917142 DOI: 10.1167/iovs.14-14216] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE The purpose of this study was to investigate the role(s) of cytochrome P450 epoxygenases (CYPs) and their products, the epoxyeicosatrienoic acids (EETs), in hypoxia-induced VEGF production and pathologic retinal angiogenesis. METHODS Human retinal astrocytes, Müller cells, and retinal microvascular endothelial cells (HRMEC) were exposed to hypoxia, and relative CYP2C expression was measured by RT-PCR. Astrocyte and Müller cell VEGF production was measured by ELISA after exposure to hypoxia and treatment with the general CYP inhibitor, SKF-525a. Human retinal microvascular endothelial cells were treated with the CYP product, 11,12-epoxyeicosatrienoic acid [EET], or SKF-525a in the presence or absence of VEGF. Proliferation of HRMEC and tube formation were assayed. Oxygen-induced retinopathy (OIR) was induced in newborn rats. Retinal CYP2C11 and CYP2C23 expression were measured by RT-PCR. The OIR rats received SKF-525a by intravitreal injection and preretinal neovascularization (NV) was quantified. Retinal VEGF protein levels were measured by ELISA. RESULTS Human retinal astrocytes were the only cells to exhibit significant induction of CYP2C8 and CYP2C9 mRNA expression by hypoxia. Astrocytes, but not Müller cells, exhibited reduced hypoxia-induced VEGF production when treated with SKF-525a. 11,12-EET induced HRMEC proliferation and tube formation, and SKF-525a inhibited VEGF-induced proliferation. Oxygen-induced retinopathy induced expression of CYP2C23, but had no effect on CYP2C11. SKF-525a inhibited retinal NV and reduced retinal VEGF levels in OIR rats. CONCLUSIONS The CYP-derived 11,12-EET may exhibit a proangiogenic biological function in the retina following stimulation by hypoxia in astrocytes. Inhibition of CYP may provide a rational therapy against retinal NV, because it can reduce VEGF production and VEGF-induced angiogenic responses in endothelial cells.
Collapse
Affiliation(s)
- Megan E Capozzi
- Departments of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| | - Gary W McCollum
- Ophthalmology and Visual Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| | - John S Penn
- Departments of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States Ophthalmology and Visual Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| |
Collapse
|
62
|
Shaikh SR, Kinnun JJ, Leng X, Williams JA, Wassall SR. How polyunsaturated fatty acids modify molecular organization in membranes: insight from NMR studies of model systems. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1848:211-9. [PMID: 24820775 DOI: 10.1016/j.bbamem.2014.04.020] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 04/23/2014] [Indexed: 11/26/2022]
Abstract
Marine long chain n-3 polyunsaturated fatty acids (PUFA), eicosapentaenoic (EPA) and docosahexaenoic acid (DHA), are bioactive molecules with clinical applications for the treatment of several diseases. In order to effectively translate these molecules into clinical trials, it is essential to establish the underlying mechanisms for n-3 PUFA. This review focuses on efforts to understand how EPA and DHA, upon incorporation into plasma membrane phospholipids, remodel the molecular organization of cholesterol-enriched lipid microdomains. We first give an overview of results from studies on cells. Paradoxical data generated from mouse studies indicate that EPA and DHA incorporate into lipid microdomains, yet in spite of their high disorder increase molecular order within the domain. We then spotlight the utility of solid state (2)H NMR spectroscopy of model bilayers as a tool for elucidating underlying mechanisms by which n-3 PUFA-containing phospholipids can regulate molecular organization of lipid microdomains. Evidence is presented demonstrating that n-3 PUFA exert differential structural effects when incorporated into phosphatidylethanolamines (PE) compared to phosphatidylcholines (PC), which explains some of the conflicting results observed in vivo. Recent studies that reveal differences between the interactions of EPA and DHA with lipid microdomains, potentially reflecting a differential in bioactivity, are finally described. Overall, we highlight the notion that NMR experiments on model membranes suggest a complex model by which n-3 PUFA reorganize lipid microdomains in vivo.
Collapse
Affiliation(s)
- Saame Raza Shaikh
- Department of Biochemistry & Molecular Biology, East Carolina Diabetes and Obesity Institute, East Carolina University, 115 Heart Drive, Room 4117, Mail Stop 743, Greenville, NC 27834, USA
| | - Jacob J Kinnun
- Department of Physics, Indiana University-Purdue University Indianapolis, 402 N. Blackford Street, Indianapolis, IN 46202-3273, USA
| | - Xiaoling Leng
- Department of Physics, Indiana University-Purdue University Indianapolis, 402 N. Blackford Street, Indianapolis, IN 46202-3273, USA
| | - Justin A Williams
- Department of Physics, Indiana University-Purdue University Indianapolis, 402 N. Blackford Street, Indianapolis, IN 46202-3273, USA
| | - Stephen R Wassall
- Department of Physics, Indiana University-Purdue University Indianapolis, 402 N. Blackford Street, Indianapolis, IN 46202-3273, USA.
| |
Collapse
|
63
|
Hu J, Popp R, Frömel T, Ehling M, Awwad K, Adams RH, Hammes HP, Fleming I. Müller glia cells regulate Notch signaling and retinal angiogenesis via the generation of 19,20-dihydroxydocosapentaenoic acid. J Biophys Biochem Cytol 2014. [DOI: 10.1083/jcb.2043oia18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|