1
|
Xu L, Chen Y, Feng S, Liu Z, Ye Y, Zhou R, Liu L. PEDF inhibits LPS-induced acute lung injury in rats and promotes lung epithelial cell survival by upregulating PPAR-γ. BMC Pulm Med 2023; 23:359. [PMID: 37740176 PMCID: PMC10517507 DOI: 10.1186/s12890-023-02666-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 09/19/2023] [Indexed: 09/24/2023] Open
Abstract
BACKGROUND The progression of acute lung injury (ALI) involves numerous pathological factors and complex mechanisms, and cause the destruction of epithelial and endothelial barriers. Pigment epithelium-derived factor (PEDF) is an angiogenesis inhibitor and a potential anti-inflammatory factor. The purpose of this study was to investigate the effect of PEDF on lipopolysaccharide (LPS)-induced ALI in rats. METHODS In vivo, pathological and injury related factors examination were performed on rat lung to investigate the effect of PEDF on ALI. In vitro, the effect of PEDF on inflammatory injury and apoptosis of lung epithelial type II RLE-6TN cell was evaluated, and the expression of inflammatory factors and related pathway proteins and PPAR-γ (in the presence or absence of PPAR-γ inhibitors) were analyzed. RESULTS In vivo results showed that PEDF inhibited the inflammatory factor expression (TNF-α, IL-6 and IL-1β) and progression of ALI and reduced lung cell apoptosis in rats. In vitro results showed that PEDF could effectively inhibit LPS-stimulated inflammatory damage and apoptosis of RLE-6TN cells. PEDF inhibited the RLE-6TN cell injury by enhancing the expression of PPAR-γ. CONCLUSIONS PEDF is an anti-inflammatory factor, which can inhibit apoptosis of lung epithelial cells by upregulating the expression of PPAR-γ and reducing LPS-induced ALI in rats.
Collapse
Affiliation(s)
- Lei Xu
- Department of Emergency Medicine, The Second Affiliated Hospital of Soochow University, Suzhou, 215004, Jiangsu, China
- Department of Emergency Medicine, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China
| | - Yifei Chen
- Department of Emergency Medicine, The Affiliated Hospital of Yangzhou University, Yangzhou, 225001, Jiangsu, China
| | - Shoujie Feng
- Thoracic Surgery Laboratory, Xuzhou Medical University, Xuzhou, China
- Department of Thoracic Surgery, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, 221002, China
| | - Zeyan Liu
- Department of Emergency Medicine, The Second Affiliated Hospital of Anhui Medical University, Hefei, 230601, Anhui, China
| | - Ying Ye
- Department of Emergency Medicine, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China
| | - Ranran Zhou
- Department of Emergency Medicine, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China
| | - Lijun Liu
- Department of Emergency Medicine, The Second Affiliated Hospital of Soochow University, Suzhou, 215004, Jiangsu, China.
| |
Collapse
|
2
|
Wang Y, Liu X, Quan X, Qin X, Zhou Y, Liu Z, Chao Z, Jia C, Qin H, Zhang H. Pigment epithelium-derived factor and its role in microvascular-related diseases. Biochimie 2022; 200:153-171. [DOI: 10.1016/j.biochi.2022.05.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 05/19/2022] [Accepted: 05/30/2022] [Indexed: 01/02/2023]
|
3
|
Qin X, Jia C, Liang J, Chen J, Liu X, Chao Z, Qin H, Yuan Y, Liu Z, Zhang Z, Dong H, Zhang H. PEDF is an antifibrosis factor that inhibits the activation of fibroblasts in a bleomycin-induced pulmonary fibrosis rat model. Respir Res 2022; 23:100. [PMID: 35459189 PMCID: PMC9027047 DOI: 10.1186/s12931-022-02027-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 04/14/2022] [Indexed: 11/25/2022] Open
Abstract
Background Idiopathic pulmonary fibrosis (IPF) is a highly heterogeneous and fatal lung disease. In addition to dense fibrous tissue, abnormal angiogenesis is also an important feature of IPF. Pigment epithelium-derived factor (PEDF) is an angiogenesis inhibitor and a potential anti-fibrous factor. The purpose of this experiment is to observe the effect of PEDF on bleomycin (BLM)-induced pulmonary fibrosis in rats. Methods In vivo, pathological examination and detection of related factors were performed on pulmonary fibrosis induced by BLM in rats, and the temporal and spatial distribution of PEDF was investigated. Furthermore, lung gene delivery (PEDF-adeno-associated virus) was performed to investigate the effect of PEDF on pulmonary fibrosis. In vitro, lentiviral vectors were used to construct PEDF over-expression or knock out primary rat lung (PRL) fibroblasts. The effect of PEDF on fibroblast activation under TGF-β1 stimulation was evaluated, and the activation of TGF-β1/smad pathway and PPAR-γ expression (in the presence or absence of PPAR-γ inhibitors) were analyzed. Results In vivo results showed that PEDF expression decreased during the inflammatory phase and increased during the fibrotic phase. PEDF could inhibit the progression of pulmonary fibrosis in rats. In vitro results showed that PEDF could effectively inhibit TGF-β1-stimulated fibroblast activation and reduce the production of α-SMA and collagen-I. PEDF could inhibit the TGF-β1/smad pathway by up-regulating the activity of PPAR-γ. Conclusions PEDF can act as an anti-fibrotic factor, inhibit fibroblast activation by upregulating PPAR-γ activity and reduce BLM-induced pulmonary fibrosis in rats. Supplementary Information The online version contains supplementary material available at 10.1186/s12931-022-02027-4.
Collapse
Affiliation(s)
- Xichun Qin
- Department of Thoracic Surgery, Affiliated Hospital of Xuzhou Medical University, 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, China.,Department of Thoracic and Cardiovascular Surgery, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, China
| | - Caili Jia
- Department of Thoracic Surgery, Affiliated Hospital of Xuzhou Medical University, 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, China
| | - Jingtian Liang
- Department of Thoracic Surgery, Affiliated Hospital of Xuzhou Medical University, 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, China
| | - Jiali Chen
- Department of Thoracic Surgery, Affiliated Hospital of Xuzhou Medical University, 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, China
| | - Xiucheng Liu
- Department of Thoracic Surgery, Affiliated Hospital of Xuzhou Medical University, 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, China
| | - Zhixiang Chao
- Department of Thoracic Surgery, Affiliated Hospital of Xuzhou Medical University, 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, China
| | - Hao Qin
- Department of Thoracic Surgery, Affiliated Hospital of Xuzhou Medical University, 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, China
| | - Yanliang Yuan
- Department of Thoracic Surgery, Affiliated Hospital of Xuzhou Medical University, 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, China
| | - Zhiwei Liu
- Public Experimental Research Center, Xuzhou Medical University, Xuzhou, 221006, Jiangsu, China
| | - Zhongming Zhang
- Department of Thoracic Surgery, Affiliated Hospital of Xuzhou Medical University, 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, China
| | - Hongyan Dong
- Morphological Research Experiment Center, Xuzhou Medical University, 209 Tongshan Road, Xuzhou, 221004, Jiangsu, China.
| | - Hao Zhang
- Department of Thoracic Surgery, Affiliated Hospital of Xuzhou Medical University, 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, China.
| |
Collapse
|
4
|
Lierova A, Kasparova J, Filipova A, Cizkova J, Pekarova L, Korecka L, Mannova N, Bilkova Z, Sinkorova Z. Hyaluronic Acid: Known for Almost a Century, but Still in Vogue. Pharmaceutics 2022; 14:pharmaceutics14040838. [PMID: 35456670 PMCID: PMC9029726 DOI: 10.3390/pharmaceutics14040838] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 04/03/2022] [Accepted: 04/04/2022] [Indexed: 02/04/2023] Open
Abstract
Hyaluronic acid (HA) has a special position among glycosaminoglycans. As a major component of the extracellular matrix (ECM). This simple, unbranched polysaccharide is involved in the regulation of various biological cell processes, whether under physiological conditions or in cases of cell damage. This review summarizes the history of this molecule’s study, its distinctive metabolic pathway in the body, its unique properties, and current information regarding its interaction partners. Our main goal, however, is to intensively investigate whether this relatively simple polymer may find applications in protecting against ionizing radiation (IR) or for therapy in cases of radiation-induced damage. After exposure to IR, acute and belated damage develops in each tissue depending upon the dose received and the cellular composition of a given organ. A common feature of all organ damage is a distinct change in composition and structure of the ECM. In particular, the important role of HA was shown in lung tissue and the variability of this flexible molecule in the complex mechanism of radiation-induced lung injuries. Moreover, HA is also involved in intermediating cell behavior during morphogenesis and in tissue repair during inflammation, injury, and would healing. The possibility of using the HA polymer to affect or treat radiation tissue damage may point to the missing gaps in the responsible mechanisms in the onset of this disease. Therefore, in this article, we will also focus on obtaining answers from current knowledge and the results of studies as to whether hyaluronic acid can also find application in radiation science.
Collapse
Affiliation(s)
- Anna Lierova
- Department of Radiobiology, Faculty of Military Health Sciences, University of Defence, 500 01 Hradec Kralove, Czech Republic; (A.F.); (J.C.); (L.P.); (Z.S.)
- Correspondence:
| | - Jitka Kasparova
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, 532 10 Pardubice, Czech Republic; (J.K.); (L.K.); (N.M.); (Z.B.)
| | - Alzbeta Filipova
- Department of Radiobiology, Faculty of Military Health Sciences, University of Defence, 500 01 Hradec Kralove, Czech Republic; (A.F.); (J.C.); (L.P.); (Z.S.)
| | - Jana Cizkova
- Department of Radiobiology, Faculty of Military Health Sciences, University of Defence, 500 01 Hradec Kralove, Czech Republic; (A.F.); (J.C.); (L.P.); (Z.S.)
| | - Lenka Pekarova
- Department of Radiobiology, Faculty of Military Health Sciences, University of Defence, 500 01 Hradec Kralove, Czech Republic; (A.F.); (J.C.); (L.P.); (Z.S.)
| | - Lucie Korecka
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, 532 10 Pardubice, Czech Republic; (J.K.); (L.K.); (N.M.); (Z.B.)
| | - Nikola Mannova
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, 532 10 Pardubice, Czech Republic; (J.K.); (L.K.); (N.M.); (Z.B.)
| | - Zuzana Bilkova
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, 532 10 Pardubice, Czech Republic; (J.K.); (L.K.); (N.M.); (Z.B.)
| | - Zuzana Sinkorova
- Department of Radiobiology, Faculty of Military Health Sciences, University of Defence, 500 01 Hradec Kralove, Czech Republic; (A.F.); (J.C.); (L.P.); (Z.S.)
| |
Collapse
|
5
|
Pigment epithelium-derived factor engineered to increase glycosaminoglycan affinity while maintaining bioactivity. Biochem Biophys Res Commun 2022; 605:148-153. [PMID: 35334413 DOI: 10.1016/j.bbrc.2022.03.079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 11/24/2022]
Abstract
Pigment epithelium-derived factor (PEDF) is a secreted protein that is essential in tissue homeostasis and is involved in multiple functions in the eye, such as antiangiogenesis and neuroprotection. However, short retention in the retinal microenvironment can limit its therapeutic effects. In this study, we modified the amino acid sequence of PEDF to increase its affinity for heparin and hyaluronic acid (HA), which are negatively charged extracellular matrix (ECM) molecules. HA is the major component of the vitreous humor. We selectively converted neutral or anionic residues into cationic residues to obtain engineered PEDF (ePEDF). Using in vitro binding assays, we demonstrate that ePEDF had higher affinity for heparin and HA than wild-type PEDF (wtPEDF). ePEDF exhibited antiangiogenic and retinal survival bioactivities. It inhibited endothelial cell proliferation and tube formation in vitro. In an ex vivo model mimicking retinal degeneration, ePEDF protected photoreceptors from cell death. The findings suggest that protein engineering is an approach to develop active PEDF with higher ECM affinity to potentially improve its retention in the retina microenvironment and in turn make it a more efficient therapeutic drug for retinal diseases.
Collapse
|
6
|
Expression and production of pigment epithelium-derived factor (PEDF) and PEDF receptor variants from mammalian and bacterial cells. Protein Expr Purif 2022; 194:106072. [PMID: 35181508 DOI: 10.1016/j.pep.2022.106072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 02/11/2022] [Accepted: 02/11/2022] [Indexed: 11/22/2022]
Abstract
Human SERPINF1 gene codes for pigment epithelium-derived factor (PEDF), a secreted glycoprotein and member of the SERPIN superfamily. To obtain large amounts of recombinant PEDF proteins, we subcloned the coding sequence of human SERPINF1 mutated versions into the pCEP4 vector and generated stably transfected HEK.Ebna cells. The cells produced and secreted recombinant PEDF proteins into the culturing media. The recombinant PEDF proteins were purified by ion-exchange column chromatography and milligram amounts of highly purified protein were recovered. PEDF has affinity for PEDF-receptor (PEDF-R), a membrane-linked lipase encoded by the PNPLA2 gene. Recombinant PEDF-R truncated versions were obtained from Escherichia coli containing expression vectors with human PNPLA2 cDNAs with 3'end deletions and by induction with isopropyl β-d-1-thiogalactopyranoside. The bacterially derived PEDF-R proteins in insoluble inclusion bodies were solubilized with urea and purified by cation-exchange column chromatography. C-terminally truncated PEDF-R versions containing the ligand binding region retained the ability to bind PEDF. The data demonstrate that mammalian-derived recombinant PEDF and bacterially derived recombinant PEDF-R can be produced and purified in large amounts for further use in structural and biological studies.
Collapse
|
7
|
Serpins in cartilage and osteoarthritis: what do we know? Biochem Soc Trans 2021; 49:1013-1026. [PMID: 33843993 PMCID: PMC8106492 DOI: 10.1042/bst20201231] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/17/2021] [Accepted: 03/04/2021] [Indexed: 12/13/2022]
Abstract
Serpins (serine proteinase inhibitors) are an ancient superfamily of structurally similar proteins, the majority of which use an elegant suicide inhibition mechanism to target serine proteinases. Despite likely evolving from a single common ancestor, the 36 human serpins have established roles regulating diverse biological processes, such as blood coagulation, embryonic development and extracellular matrix (ECM) turnover. Genetic mutations in serpin genes underpin a host of monogenic disorders — collectively termed the ‘serpinopathies’ — but serpin dysregulation has also been shown to drive pathological mechanisms in many common diseases. Osteoarthritis is a degenerative joint disorder, characterised by the progressive destruction of articular cartilage. This breakdown of the cartilage is driven by the metalloproteinases, and it has long been established that an imbalance of metalloproteinases to their inhibitors is of critical importance. More recently, a role for serine proteinases in cartilage destruction is emerging; including the activation of latent matrix metalloproteinases and cell-surface receptors, or direct proteolysis of the ECM. Serpins likely regulate these processes, as well as having roles beyond serine proteinase inhibition. Indeed, serpins are routinely observed to be highly modulated in osteoarthritic tissues and fluids by ‘omic analysis, but despite this, they are largely ignored. Confusing nomenclature and an underappreciation for the role of serine proteinases in osteoarthritis (OA) being the likely causes. In this narrative review, serpin structure, biochemistry and nomenclature are introduced, and for the first time, their putative importance in maintaining joint tissues — as well as their dysregulation in OA — are explored.
Collapse
|
8
|
Dixit S, Polato F, Samardzija M, Abu-Asab M, Grimm C, Crawford SE, Becerra SP. PEDF deficiency increases the susceptibility of rd10 mice to retinal degeneration. Exp Eye Res 2020; 198:108121. [PMID: 32721425 DOI: 10.1016/j.exer.2020.108121] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 06/09/2020] [Accepted: 06/15/2020] [Indexed: 12/29/2022]
Abstract
The SERPINF1 gene encodes pigment epithelium-derived factor (PEDF), a member of the serpin superfamily with neurotrophic and antiangiogenic properties in the retina. We hypothesized that absence of PEDF would lead to increased stress-associated retinal degeneration in Serpinf1 null mice. Accordingly, using a Serpinf1 null mouse model, we investigated the impact of PEDF absence on retinal morphology, and susceptibility to induced and inherited retinal degeneration. We studied the pattern of Serpinf1 expression in the mouse retina layers. PEDF protein was detected by western blotting. Transmission electron microscopy was performed on mouse retina. Serpinf1 null mice and wild type littermates were injected with NaIO3 (30 mg/kg body weight) intraperitonially. At post-injection day 1, 3, 4, 6 and 8 mice were euthanized, and eyes were enucleated. Serpinf1 null and rd10 double mutant mice were generated and their eyes enucleated at different time points from post-natal day 15 to post-natal day 28. Enucleated eyes were processed for hematoxylin and eosin staining and histopathological evaluations. We found that Serpinf1 was expressed in the retinal pigment epithelium, in the inner nuclear layer and in the ganglion cell layer, but undetectable in the outer nuclear layer of wild type mice. Plasma PEDF protein levels were undetectable in Serpinf1 null animals. RPE atrophy and retinal thinning were observed in NaIO3-treated wild type mice that progressed with time post-injection. NaIO3-treated Serpinf1 null mice showed comparatively better retinal morphology than wild type mice at day 4 post-injection. However, the absence of PEDF in Serpinf1 null x rd10 mice increased the susceptibility to retinal degeneration relative to that of rd10 mice. We concluded that histopathological evaluation of retinas lacking PEDF showed that removal of the Serpinf1 gene may activate PEDF-independent compensatory mechanisms to protect the retina against oxidative stress, while it increases the susceptibility to degenerate the retina in inherited retinal degeneration models.
Collapse
Affiliation(s)
- Shivani Dixit
- Section of Protein Structure and Function, LRCMB-NEI-NIH, Bethesda, MD, USA
| | - Federica Polato
- Section of Protein Structure and Function, LRCMB-NEI-NIH, Bethesda, MD, USA
| | - Marijana Samardzija
- Laboratory of Retinal Cell Biology, Department of Ophthalmology, University of Zurich, Zurich, Switzerland
| | | | - Christian Grimm
- Laboratory of Retinal Cell Biology, Department of Ophthalmology, University of Zurich, Zurich, Switzerland
| | - Susan E Crawford
- Department of Surgery, NorthShore University Health System Research Institute, Evanston, IL, USA
| | - S Patricia Becerra
- Section of Protein Structure and Function, LRCMB-NEI-NIH, Bethesda, MD, USA.
| |
Collapse
|
9
|
Spatiotemporal regulation of PEDF signaling by type I collagen remodeling. Proc Natl Acad Sci U S A 2020; 117:11450-11458. [PMID: 32385162 DOI: 10.1073/pnas.2004034117] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Dynamic remodeling of the extracellular matrix affects many cellular processes, either directly or indirectly, through the regulation of soluble ligands; however, the mechanistic details of this process remain largely unknown. Here we propose that type I collagen remodeling regulates the receptor-binding activity of pigment epithelium-derived factor (PEDF), a widely expressed secreted glycoprotein that has multiple important biological functions in tissue and organ homeostasis. We determined the crystal structure of PEDF in complex with a disulfide cross-linked heterotrimeric collagen peptide, in which the α(I) chain segments-each containing the respective PEDF-binding region (residues 930 to 938)-are assembled with an α2α1α1 staggered configuration. The complex structure revealed that PEDF specifically interacts with a unique amphiphilic sequence, KGHRGFSGL, of the type I collagen α1 chain, with its proposed receptor-binding sites buried extensively. Molecular docking demonstrated that the PEDF-binding surface of type I collagen contains the cross-link-susceptible Lys930 residue of the α1 chain and provides a good foothold for stable docking with the α1(I) N-telopeptide of an adjacent triple helix in the fibril. Therefore, the binding surface is completely inaccessible if intermolecular crosslinking between two crosslink-susceptible lysyl residues, Lys9 in the N-telopeptide and Lys930, is present. These structural analyses demonstrate that PEDF molecules, once sequestered around newly synthesized pericellular collagen fibrils, are gradually liberated as collagen crosslinking increases, making them accessible for interaction with their target cell surface receptors in a spatiotemporally regulated manner.
Collapse
|
10
|
Brook N, Brook E, Dharmarajan A, Chan A, Dass CR. Pigment epithelium-derived factor regulation of neuronal and stem cell fate. Exp Cell Res 2020; 389:111891. [DOI: 10.1016/j.yexcr.2020.111891] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Revised: 02/02/2020] [Accepted: 02/04/2020] [Indexed: 01/25/2023]
|
11
|
Kim HW, Roh KH, Kim SW, Park SJ, Lim NY, Jung H, Choi IW, Park S. Type I pig collagen enhances the efficacy of PEDF 34-mer peptide in a mouse model of laser-induced choroidal neovascularization. Graefes Arch Clin Exp Ophthalmol 2019; 257:1709-1717. [PMID: 31222405 DOI: 10.1007/s00417-019-04394-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 05/13/2019] [Accepted: 06/10/2019] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Pigment epithelium-derived factor (PEDF)-derived 34-mer peptide (PEDF34, Asp44-Asn77) has anti-angiogenic activity but has limitations in clinical application because of an inverted bell-shaped dose-effect relationship and a short half-life. In this study, we attempted to mitigate these problems by mixing PEDF34 with type I collagen. METHODS The anti-angiogenic activity of the PEDF34/atelocollagen mixture was evaluated by HUVEC tube formation assay and in a laser-induced choroidal neovascular (CNV) mouse model. PEDF34 and/or collagen were administrated using intravitreal injections or eye drops. CNV lesion size was quantified using FITC-dextran-perfused retinal whole mounts. Western blot analysis and inhibitor assays were used to define the action mechanisms of PEDF34 and the mixture. RESULTS Collagen broadened the effective dose range of PEDF34 in the tube formation assay by > 250 times (from 0.2 to 50 nM). In the CNV model, five intravitreal injections of PEDF34 were required for therapeutic effect, whereas the mixture had a significant therapeutic effect following a single injection. Eye drops of the mixture showed significantly stronger CNV-suppressive effects than drops of PEDF34 alone. The anti-angiogenic activity of PEDF34 might be mediated by inhibition of ERK and JNK activation by VEGF, and collagen potentiated these effects. CONCLUSIONS Collagen can serve as a carrier and reservoir of PEDF34. PEDF peptide/collagen mixture is easy to prepare than conventional methods for maintaining the therapeutic effect of PEDF peptide.
Collapse
Affiliation(s)
- Hyun Woong Kim
- Department of Ophthalmology, Haeundae Paik Hospital, College of Medicine, Inje University, Busan, Republic of Korea
| | - Kug-Hwan Roh
- Department of Microbiology and Immunology, College of Medicine, Inje University, Busan, 47392, Republic of Korea
| | - Seong Wook Kim
- Department of Microbiology and Immunology, College of Medicine, Inje University, Busan, 47392, Republic of Korea
| | - Sung Jae Park
- Department of Internal Medicine, Busan Paik Hospital, College of Medicine, Inje University, Busan, Republic of Korea.,Paik Institute for Clinical Research, College of Medicine, Inje University, Busan, Republic of Korea
| | - Na-Young Lim
- Department of Internal Medicine, Busan Paik Hospital, College of Medicine, Inje University, Busan, Republic of Korea.,Paik Institute for Clinical Research, College of Medicine, Inje University, Busan, Republic of Korea
| | - Hana Jung
- Department of Microbiology and Immunology, College of Medicine, Inje University, Busan, 47392, Republic of Korea
| | - Il-Whan Choi
- Department of Microbiology and Immunology, College of Medicine, Inje University, Busan, 47392, Republic of Korea
| | - SaeGwang Park
- Department of Microbiology and Immunology, College of Medicine, Inje University, Busan, 47392, Republic of Korea. .,Paik Institute for Clinical Research, College of Medicine, Inje University, Busan, Republic of Korea.
| |
Collapse
|
12
|
Huang KT, Lin CC, Tsai MC, Chen KD, Chiu KW. Pigment epithelium-derived factor in lipid metabolic disorders. Biomed J 2019; 41:102-108. [PMID: 29866598 PMCID: PMC6138776 DOI: 10.1016/j.bj.2018.02.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 01/29/2018] [Accepted: 02/13/2018] [Indexed: 01/10/2023] Open
Abstract
Pigment epithelium-derived factor (PEDF) is a secreted glycoprotein that has anti-angiogenic, anti-proliferative, neurotrophic and immunomodulatory properties. PEDF has recently emerged as a critical metabolic regulatory protein since the discovery of its modulatory activities in the lipolytic pathway by binding to adipose triglyceride lipase (ATGL). Despite being beneficial in maintaining the homeostasis of hepatic lipid accumulation, PEDF has been uncovered an unfavorable role associated with insulin resistance. The molecular events that connect these two apparent distinct observations have been controversial and remained largely unknown. Therefore in this short review, we attempt to summarize the current findings of PEDF regarding its lipid metabolic functions and provide perspectives in identifying PEDF as a potential therapeutic target in lipid disorders.
Collapse
Affiliation(s)
- Kuang-Tzu Huang
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
| | - Chih-Che Lin
- Liver Transplantation Center, Department of Surgery, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Ming-Chao Tsai
- Division of Hepato-Gastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Kuang-Den Chen
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - King-Wah Chiu
- Division of Hepato-Gastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| |
Collapse
|
13
|
Winokur PN, Subramanian P, Bullock JL, Arocas V, Becerra SP. Comparison of two neurotrophic serpins reveals a small fragment with cell survival activity. Mol Vis 2017; 23:372-384. [PMID: 28706437 PMCID: PMC5501690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 06/30/2017] [Indexed: 10/31/2022] Open
Abstract
PURPOSE Protease nexin-1 (PN-1), a serpin encoded by the SERPINE2 gene, has serine protease inhibitory activity and neurotrophic properties in the brain. PN-1 inhibits retinal angiogenesis; however, PN-1's neurotrophic capacities in the retina have not yet been evaluated. Pigment epithelium-derived factor (PEDF) is a serpin that exhibits neurotrophic and antiangiogenic activities but lacks protease inhibitory properties. The aim of this study is to compare PN-1 and PEDF. METHODS Sequence comparisons were performed using computer bioinformatics programs. Mouse and bovine eyes, human retina tissue, and ARPE-19 cells were used to prepare RNA and protein samples. Interphotoreceptor matrix lavage was obtained from bovine eyes. Gene expression and protein levels were evaluated with reverse-transcription PCR (RT-PCR) and western blotting, respectively. Recombinant human PN-1, a version of PN-1 referred to as PN-1[R346A] lacking serine protease inhibitory activity, and PEDF proteins were used, as well as synthetic peptides designed from PEDF and PN-1 sequences. Survival activity in serum-starved, rat-derived retinal precursor (R28) cells was assessed with terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) cell death assays. Bcl2 levels were measured with RT-PCR. RESULTS PN-1 is analogous in primary and tertiary structure to PEDF. A region in PN-1 shares homology with the neurotrophic active region of PEDF, a 17-residue region within alpha helix C. The native human retina, ARPE-19 cells, and murine RPE and retina expressed the gene for PN-1 (SERPINE2 and Serpine2 mRNA). The retina, ARPE-19 cell lysates, and bovine interphotoreceptor matrix contained PN-1 protein. The addition of PN-1, PN-1[R346A], or the 17mer peptide of PN-1 to serum-starved retina cells decreased the number of TUNEL-positive nuclei relative to the untreated cells, such as PEDF. PN-1, PN-1[R346A], and PN-1-17mer treatments increased the Bcl2 transcript levels in serum-starved cells, as seen with PEDF. CONCLUSIONS PN-1 and PEDF share structural and functional features, and expression patterns in the retina. These serpins' mechanisms of action as cell survival factors are independent of serine protease inhibition. We have identified PN-1 as a novel factor for the retina that may play a neuroprotective role in vivo, and small peptides as relevant candidates for preventing retinal degeneration.
Collapse
Affiliation(s)
- Paige N. Winokur
- NIH, NEI, Section of Protein Structure and Function, Bethesda, MD
| | | | - Jeanee L. Bullock
- NIH, NEI, Section of Protein Structure and Function, Bethesda, MD,Georgetown University, Department of Biochemistry and Molecular and Cellular Biology, Washington, DC
| | | | | |
Collapse
|
14
|
Nakamura DS, Hollander JM, Uchimura T, Nielsen HC, Zeng L. Pigment Epithelium-Derived Factor (PEDF) mediates cartilage matrix loss in an age-dependent manner under inflammatory conditions. BMC Musculoskelet Disord 2017; 18:39. [PMID: 28122611 PMCID: PMC5264335 DOI: 10.1186/s12891-017-1410-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 01/16/2017] [Indexed: 02/04/2023] Open
Abstract
Background Inflammation is a major cause of cartilage destruction and leads to the imbalance of metabolic activities in the arthritic joint. Pigment epithelium-derived factor (PEDF) has been reported to have both pro- and anti-inflammatory activities in various cell types and to be upregulated in the arthritic joint, but its role in joint destruction is unclear. Our aim was to investigate the role of PEDF in cartilage degeneration under inflammatory conditions. Methods PEDF was ectopically expressed in primary human articular chondrocytes, and catabolic gene expression and protein secretion in response to the pro-inflammatory cytokine interleukin 1 beta (IL-1β) were evaluated. Metatarsal bones from PEDF-deficient and wild type mice were cultured in the presence or absence of IL-1β. Cartilage matrix integrity and matrix metalloproteinases MMP-1, MMP-3, and MMP-13 were evaluated. PEDF-deficient and wild type mice were evaluated in the monosodium iodoacetate (MIA) inflammatory joint destruction animal model to determine the role of PEDF in inflammatory arthritis in vivo. Student’s t-tests and Mann–Whitney tests were employed where appropriate, for parametric and non-parametric data, respectively. Results We showed that PEDF protein levels were higher in human osteoarthritis samples compared to normal samples. We demonstrated that ectopic PEDF expression in primary human articular chondrocytes exacerbated catabolic gene expression in the presence of IL-1β. In whole bone organ cultures, IL-1β induced MMP-1, MMP-3 and MMP-13 protein production, and caused significant cartilage matrix loss. Interestingly, Toluidine Blue staining showed that PEDF-deficient bones from 29 week old animals, but not 10 week old animals, had reduced matrix loss in response to IL-1β compared to their wild type counterparts. In addition, PEDF-deficiency in 29 week old animals preserved matrix integrity and protected against cell loss in the MIA joint destruction model in vivo. Conclusion We conclude that PEDF exacerbates cartilage degeneration in an age-dependent manner under an inflammatory setting. This is the first study identifying a specific role for PEDF in joint inflammation and highlights the multi-faceted activities of PEDF. Electronic supplementary material The online version of this article (doi:10.1186/s12891-017-1410-y) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Daisy S Nakamura
- Program in Cell, Molecular and Developmental Biology, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA, USA
| | - Judith M Hollander
- Program in Cell, Molecular and Developmental Biology, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA, USA
| | - Tomoya Uchimura
- Program in Cell, Molecular and Developmental Biology, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA, USA
| | - Heber C Nielsen
- Program in Cell, Molecular and Developmental Biology, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA, USA. .,Department of Pediatrics, Tufts Medical Center, Boston, MA, USA.
| | - Li Zeng
- Program in Cell, Molecular and Developmental Biology, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA, USA. .,Department of Integrative Physiology and Pathobiology, Tufts University School of Medicine, Boston, MA, USA. .,Department of Orthopaedics, Tufts Medical Center, Boston, MA, USA.
| |
Collapse
|
15
|
Baggenstoss BA, Harris EN, Washburn JL, Medina AP, Nguyen L, Weigel PH. Hyaluronan synthase control of synthesis rate and hyaluronan product size are independent functions differentially affected by mutations in a conserved tandem B-X7-B motif. Glycobiology 2016; 27:154-164. [PMID: 27558839 DOI: 10.1093/glycob/cww089] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 08/18/2016] [Accepted: 08/18/2016] [Indexed: 01/27/2023] Open
Abstract
Hyaluronan synthases (HAS) normally make large (>MDa) hyaluronan (HA) products. Smaller HA fragments (e.g. 100-400 kDa) produced in vivo are associated with inflammation and cell signaling by HA receptors that bind small, but not large, HA. Although HA fragments can arise from breakdown by hyaluronidases, HAS might also be regulated directly to synthesize small HA. Here we examined the Streptococcus equisimilis HAS (SeHAS) C-terminus, which contains a tandem B-X7-B motif (K398-X7-R406-X7-K414), by testing the effects of 27 site-specific scanning mutations and 7 C-terminal truncations on HA synthesis activity and weight-average mass. Although HAS enzymes cannot be HA-binding proteins, these motifs are highly conserved within the Class I HAS family. Fifteen Arg406 mutants made large MDa HA (86-110% wildtype size), with specific activities from 70% to 177% of wildtype. In contrast, 10 of 12 Lys398 mutants made HA that was 8-14% of wildtype size (≤250-480 kDa), with specific activities from 14% to 64% of wildtype. Four nearly inactive (2% wildtype activity) C-terminal truncation mutants made MDa HA (56-71% wildtype). The results confirm earlier findings with Cys-mutants [Weigel PH, Baggenstoss BA. 2012. Hyaluronan synthase polymerizing activity and control of product size are discrete enzyme functions that can be uncoupled by mutagenesis of conserved cysteines. Glycobiology 22:1302-1310] that HAS uses two independent activities to control HA size and HA synthesis rate; these are two separate functions. We conclude that HAS regulatory modifications that alter tandem B-X7-B motif conformation could mimic these mutagenesis-induced effects, allowing HAS in vivo to make small HA directly. The results also support a model in which the tandem-motif region is part of the intra-HAS pore and interacts directly with HA.
Collapse
Affiliation(s)
- Bruce A Baggenstoss
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Edward N Harris
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Jennifer L Washburn
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Andria P Medina
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Long Nguyen
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Paul H Weigel
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| |
Collapse
|
16
|
Belkacemi L, Zhang SX. Anti-tumor effects of pigment epithelium-derived factor (PEDF): implication for cancer therapy. A mini-review. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2016; 35:4. [PMID: 26746675 PMCID: PMC4706649 DOI: 10.1186/s13046-015-0278-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 12/22/2015] [Indexed: 12/22/2022]
Abstract
Pigment epithelium-derived factor (PEDF) is a secreted glycoprotein and a non-inhibitory member of the serine protease inhibitor (serpin) family. It is widely expressed in human fetal and adult tissues but its expression decreases with age and in malignant tissues. The main anti-cancer activities of PEDF derive from its dual effects, either indirectly on the tumor microenvironment (indirect antitumor action) or directly on the tumor itself (direct antitumor influence). The indirect antitumor activities of PEDF were uncovered from the early findings that it stimulates retinoblastoma cell differentiation and that additionally it possesses anti-angiogenic, anti-tumorigenic and anti-metastatic properties. The mechanisms of its direct antitumor effect, however, have not been fully elucidated. This review highlights recent progress in our understanding of the multifunctional activities of PEDF and, in particular, its anti-cancer signaling mechanisms. Additionally, we discuss the possibility of using novel phosphaplatin compounds that can upregulate PEDF expression as a chemotherapy for cancer treatment.
Collapse
Affiliation(s)
- Louiza Belkacemi
- Center for Nuclear Receptors and Cell Signaling, University of Houston, Houston, TX, 77204, USA.
| | - Shaun Xiaoliu Zhang
- Department of Biology and Biochemistry, University of Houston, Houston, TX, 77204, USA. .,Center for Nuclear Receptors and Cell Signaling, University of Houston, Houston, TX, 77204, USA.
| |
Collapse
|
17
|
Lee SJ, Duncan DS, Echevarria FD, McLaughlin WM, Hatcher JB, Sappington RM. Pressure-Induced Alterations in PEDF and PEDF-R Expression: Implications for Neuroprotective Signaling in Glaucoma. ACTA ACUST UNITED AC 2015; 6. [PMID: 26807306 PMCID: PMC4721587 DOI: 10.4172/2155-9570.1000491] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Introduction Alterations in neuron-glia signaling are implicated in glaucoma, a neurodegenerative disease characterized by retinal ganglion cell (RGC) death. Pigment epithelium derived factor (PEDF) is a secreted protein with potential neuroprotective qualities in retinal disease, including chronic ocular hypertension. Here we sought to determine whether moderate, short-term elevations in IOP alter PEDF signaling and whether pressure-induced PEDF signaling directly impacts RGC apoptosis. Methods In retina from naïve mice and mice with unilateral, microbead-induced glaucoma, we examined expression and cell type-specific localization of PEDF and its receptor (PEDF-R), using quantitative PCR and immunohistochemistry. Using primary cultures of purified RGCs and Müller cells, we examined cell type-specific expression of PEDF in response to 48 hours of elevated hydrostatic pressure, using multiplex ELISA and immunocytochemistry. We also measured pressure-induced apoptosis of RGCs in the presence or absence of atglistatin, a potent and selective inhibitor of PEDF-R, and recombinant PEDF, using TUNEL assays. Results PEDF and PEDF-R are constitutively expressed in naïve retina, primarily in the ganglion cell and nerve fiber layers. Elevated IOP increases PEDF and PEDF-R expression, particularly associated with RGCs and Müller cells. Elevated pressure in vitro increased PEDF secretion by 6-fold in RGCs and trended towards an increase in expression by Müller cells, as compared to ambient pressure. This was accompanied by changes in the subcellular localization of PEDF-R in both cell types. Inhibition of PEDF signaling with atglistatin increased pressure-induced apoptosis in RGCs and treatment with recombinant PEDF inhibited pressure-induced apoptosis, both in a dose-dependent manner. Conclusion Our findings suggest that moderate, short-term elevations in IOP promote PEDF signaling via up-regulation of both PEDF and PEDF-R. Based on in vivo and in vitro studies, this PEDF signaling likely arises from both Müller cells and RGCs, and has the potential to directly inhibit RGC apoptosis.
Collapse
Affiliation(s)
- Sean J Lee
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, USA
| | - D'Anne S Duncan
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, USA
| | | | | | - Jeremy B Hatcher
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, USA
| | - Rebecca M Sappington
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, USA; Department of Pharmacology, Vanderbilt University Medical Center, USA
| |
Collapse
|
18
|
Kenealey J, Subramanian P, Comitato A, Bullock J, Keehan L, Polato F, Hoover D, Marigo V, Becerra SP. Small Retinoprotective Peptides Reveal a Receptor-binding Region on Pigment Epithelium-derived Factor. J Biol Chem 2015; 290:25241-53. [PMID: 26304116 DOI: 10.1074/jbc.m115.645846] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Indexed: 11/06/2022] Open
Abstract
The cytoprotective effects of pigment epithelium-derived factor (PEDF) require interactions between an as of a yet undefined region with a distinct ectodomain on the PEDF receptor (PEDF-R). Here we characterized the area in PEDF that interacts with PEDF-R to promote photoreceptor survival. Molecular docking studies suggested that the ligand binding site of PEDF-R interacts with the neurotrophic region of PEDF (44-mer, positions 78-121). Binding assays demonstrated that PEDF-R bound the 44-mer peptide. Moreover, peptide P1 from the PEDF-R ectodomain had affinity for the 44-mer and a shorter fragment within it, 17-mer (positions 98-114). Single residue substitutions to alanine along the 17-mer sequence were designed and tested for binding and biological activity. Altered 17-mer[R99A] did not bind to the P1 peptide, whereas 17-mer[H105A] had higher affinity than the unmodified 17-mer. Peptides 17-mer, 17-mer[H105A], and 44-mer exhibited cytoprotective effects in cultured retina R28 cells. Intravitreal injections of these peptides and PEDF in the rd1 mouse model of retinal degeneration decreased the numbers of dying photoreceptors, 17-mer[H105A] being most effective. The blocking peptide P1 hindered their protective effects both in retina cells and in vivo. Thus, in addition to demonstrating that the region composed of positions 98-114 of PEDF contains critical residues for PEDF-R interaction that mediates survival effects, the findings reveal distinct small PEDF fragments with neurotrophic effects on photoreceptors.
Collapse
Affiliation(s)
| | | | - Antonella Comitato
- the Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy, and
| | - Jeanee Bullock
- From the National Eye Institute and the Department of Biochemistry and Molecular and Cellular Biology, Georgetown University, Washington, D. C. 20057
| | | | | | - David Hoover
- the Center for Information Technology, National Institutes of Health, Bethesda, Maryland 20892
| | - Valeria Marigo
- the Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy, and
| | | |
Collapse
|
19
|
Wietecha MS, Król MJ, Michalczyk ER, Chen L, Gettins PG, DiPietro LA. Pigment epithelium-derived factor as a multifunctional regulator of wound healing. Am J Physiol Heart Circ Physiol 2015; 309:H812-26. [PMID: 26163443 DOI: 10.1152/ajpheart.00153.2015] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 07/08/2015] [Indexed: 01/12/2023]
Abstract
During dermal wound repair, hypoxia-driven proliferation results in dense but highly permeable, disorganized microvascular networks, similar to those in solid tumors. Concurrently, activated dermal fibroblasts generate an angiopermissive, provisional extracellular matrix (ECM). Unlike cancers, wounds naturally resolve via blood vessel regression and ECM maturation, which are essential for reestablishing tissue homeostasis. Mechanisms guiding wound resolution are poorly understood; one candidate regulator is pigment epithelium-derived factor (PEDF), a secreted glycoprotein. PEDF is a potent antiangiogenic in models of pathological angiogenesis and a promising cancer and cardiovascular disease therapeutic, but little is known about its physiological function. To examine the roles of PEDF in physiological wound repair, we used a reproducible model of excisional skin wound healing in BALB/c mice. We show that PEDF is abundant in unwounded and healing skin, is produced primarily by dermal fibroblasts, binds to resident microvascular endothelial cells, and accumulates in dermal ECM and epidermis. PEDF transcript and protein levels were low during the inflammatory and proliferative phases of healing but increased in quantity and colocalization with microvasculature during wound resolution. Local antibody inhibition of endogenous PEDF delayed vessel regression and collagen maturation during the remodeling phase. Treatment of wounds with intradermal injections of exogenous, recombinant PEDF inhibited nascent angiogenesis by repressing endothelial proliferation, promoted vascular integrity and function, and increased collagen maturity. These results demonstrate that PEDF contributes to the resolution of healing wounds by causing regression of immature blood vessels and stimulating maturation of the vascular microenvironment, thus promoting a return to tissue homeostasis after injury.
Collapse
Affiliation(s)
- Mateusz S Wietecha
- Center for Wound Healing and Tissue Regeneration, College of Dentistry, University of Illinois at Chicago, Chicago, Illinois; and
| | - Mateusz J Król
- Center for Wound Healing and Tissue Regeneration, College of Dentistry, University of Illinois at Chicago, Chicago, Illinois; and
| | - Elizabeth R Michalczyk
- Center for Wound Healing and Tissue Regeneration, College of Dentistry, University of Illinois at Chicago, Chicago, Illinois; and
| | - Lin Chen
- Center for Wound Healing and Tissue Regeneration, College of Dentistry, University of Illinois at Chicago, Chicago, Illinois; and
| | - Peter G Gettins
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, Illinois
| | - Luisa A DiPietro
- Center for Wound Healing and Tissue Regeneration, College of Dentistry, University of Illinois at Chicago, Chicago, Illinois; and
| |
Collapse
|
20
|
PEDF and its roles in physiological and pathological conditions: implication in diabetic and hypoxia-induced angiogenic diseases. Clin Sci (Lond) 2015; 128:805-23. [PMID: 25881671 PMCID: PMC4557399 DOI: 10.1042/cs20130463] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Pigment epithelium-derived factor (PEDF) is a broadly expressed multifunctional member of the serine proteinase inhibitor (serpin) family. This widely studied protein plays critical roles in many physiological and pathophysiological processes, including neuroprotection, angiogenesis, fibrogenesis and inflammation. The present review summarizes the temporal and spatial distribution patterns of PEDF in a variety of developing and adult organs, and discusses its functions in maintaining physiological homoeostasis. The major focus of the present review is to discuss the implication of PEDF in diabetic and hypoxia-induced angiogenesis, and the pathways mediating PEDF's effects under these conditions. Furthermore, the regulatory mechanisms of PEDF expression, function and degradation are also reviewed. Finally, the therapeutic potential of PEDF as an anti-angiogenic drug is briefly summarized.
Collapse
|
21
|
Johnston EK, Francis MK, Knepper JE. Recombinant pigment epithelium-derived factor PEDF binds vascular endothelial growth factor receptors 1 and 2. In Vitro Cell Dev Biol Anim 2015; 51:730-8. [PMID: 25948043 DOI: 10.1007/s11626-015-9884-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 02/22/2015] [Indexed: 01/18/2023]
Abstract
Angiogenesis, or the formation of new blood vessels, is stimulated by angiogenic factors such as vascular endothelial growth factor (VEGF). Pigment epithelium-derived factor (PEDF) is a potent inhibitor of angiogenesis. To explore the mechanism by which PEDF acts, recombinant PEDF was expressed with a 6x-His tag (for purification) and a green fluorescent protein (GFP) tag. The PEDF fusion protein was confirmed to be active in inhibition of endothelial cell proliferation and migration. Direct binding of PEDF to both vascular endothelial growth factor receptor-1 (VEGFR-1) and VEGFR-2 was demonstrated in an in vitro assay similar to an enzyme-linked immunosorbent assay (ELISA). PEDF was shown by immune-confocal microscopy to be localized within treated endothelial cells. When VEGF-stimulated endothelial cells were incubated with PEDF the VEGF receptors showed intracellular localization. These data suggest that the interaction between PEDF and VEGFR-1 or VEGFR-2 may be a possible mechanism for inhibiting angiogenesis. PEDF may be binding to the VEGF receptors to promote their internalization and/or degradation to limit VEGF responses in treated cells.
Collapse
Affiliation(s)
- Erin K Johnston
- Janssen Research and Development, LLC, Pharma R&D Quality and Compliance, 1400 McKean Road, Building 32-12334, Spring House, PA, 19477, USA,
| | | | | |
Collapse
|
22
|
Ishikawa M, Sawada Y, Yoshitomi T. Structure and function of the interphotoreceptor matrix surrounding retinal photoreceptor cells. Exp Eye Res 2015; 133:3-18. [DOI: 10.1016/j.exer.2015.02.017] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 02/20/2015] [Accepted: 02/20/2015] [Indexed: 12/21/2022]
|
23
|
Glycosaminoglycan and Collagen Facilitate the Degradation of Pigment Epithelium-Derived Factor by Chymotrypsin. Biosci Biotechnol Biochem 2014; 77:1628-32. [DOI: 10.1271/bbb.130069] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
24
|
Hartwell R, Lai A, Ghahary A. Modulation of extracellular matrix through keratinocyte–fibroblast crosstalk. ACTA ACUST UNITED AC 2014. [DOI: 10.1586/edm.09.55] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
25
|
Becerra SP, Notario V. The effects of PEDF on cancer biology: mechanisms of action and therapeutic potential. Nat Rev Cancer 2013; 13:258-71. [PMID: 23486238 PMCID: PMC3707632 DOI: 10.1038/nrc3484] [Citation(s) in RCA: 162] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The potent actions of pigment epithelium-derived factor (PEDF) on tumour-associated cells, and its extracellular localization and secretion, stimulated research on this multifunctional serpin. Such studies have identified several PEDF receptors and downstream signalling pathways. Known cellular PEDF responses have expanded from the initial discovery that PEDF induces retinoblastoma cell differentiation to its anti-angiogenic, antitumorigenic and antimetastatic properties. Although the diversity of PEDF activities seems to be complex, they are consistent with the varied mechanisms that regulate this multimodal factor. If PEDF is to be used for cancer management, a deeper appreciation of its many functions and mechanisms of action is needed.
Collapse
Affiliation(s)
- S Patricia Becerra
- National Eye Institute, US National Institutes of Health, Bethesda, Maryland, USA.
| | | |
Collapse
|
26
|
Popp N, Chu XK, Shen D, Tuo J, Chan CC. Evaluating Potential Therapies in a Mouse Model of Focal Retinal Degeneration with Age-related Macular Degeneration (AMD)-Like Lesions. ACTA ACUST UNITED AC 2013; 4:1000296. [PMID: 24432192 PMCID: PMC3890246 DOI: 10.4172/2155-9570.1000296] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Although the mouse has no macula leutea, its neuroretina and retinal pigment epithelium (RPE) can develop lesions mimicking certain features of age-related macular degeneration (AMD). Differences between the Ccl2 and Cx3cr1 double deficient mouse on Crb1rd8(rd8) background (DKOrd8) and the Crb1rd8 mouse in photoreceptor and RPE pathology, as well as ocularA2E contents and immune responses, show that DKOrd8 recapitulates some human AMD-like features in addition to rd8 retinal dystrophy/degeneration. Different therapeutic interventions have been demonstrated to be effective on the AMD-like features of DKOrd8 mice. The use of the DKOrd8 model and C57BL/6N (wild type, WT) mice as group controls (4 groups) to test treatments such as high omega-3 polyunsaturated fatty acid (n-3) diet has, for example, shown the beneficial effect of n-3 on AMD-like lesions by anti-inflammatory action of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). The use of self-control in the DKOrd8 mouse by treating one eye and using the contralateral eye as the control for the same mouse allows for appropriate interventional experiments and evaluates various novel therapeutic agents. Three examples will be briefly presented and discussed: (1) tumor necrosis factor-inducible gene 6 recombinant protein (TSG-6) arrests the AMD-like lesions via modulation of ocular immunological gene expression, e.g., Il-17a; (2) adeno-associated virus encoding sIL-17R (AAV2.sIL17R) stabilizes the AMD-like lesions; and (3) pigment epithelium-derived factor (PEDF) ameliorates the AMD-lesions by its anti-inflammatory, anti-apoptotic and neuroprotective roles. Therefore, the DKOrd8 mouse model can be useful and appropriate for therapeutic compound screening in the management of human AMD.
Collapse
Affiliation(s)
- Nicholas Popp
- Immunopathology Section, Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Dr., 10/10N103, NIH/NEI, Bethesda, MD, 20892-1857, USA
| | - Xi K Chu
- Immunopathology Section, Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Dr., 10/10N103, NIH/NEI, Bethesda, MD, 20892-1857, USA
| | - Defen Shen
- Immunopathology Section, Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Dr., 10/10N103, NIH/NEI, Bethesda, MD, 20892-1857, USA
| | - Jingsheng Tuo
- Immunopathology Section, Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Dr., 10/10N103, NIH/NEI, Bethesda, MD, 20892-1857, USA
| | - Chi-Chao Chan
- Immunopathology Section, Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Dr., 10/10N103, NIH/NEI, Bethesda, MD, 20892-1857, USA
| |
Collapse
|
27
|
Identification of pigment epithelium-derived factor protein forms with distinct activities on tumor cell lines. J Biomed Biotechnol 2012; 2012:425907. [PMID: 22701303 PMCID: PMC3373277 DOI: 10.1155/2012/425907] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Accepted: 03/07/2012] [Indexed: 11/18/2022] Open
Abstract
Purpose. Pigment epithelium-derived factor (PEDF) is a multifunctional serpin. The purpose of this study is to identify PEDF protein forms and investigate their biological activities on tumor cell lines. Methods. Recombinant human PEDF proteins were purified by cation- and anion-exchange column chromatography. They were subjected to SDS-PAGE, IEF, deglycosylation, heparin affinity chromatography, and limited proteolysis. Cell viability, real-time electrical impedance of cells, and wound healing assays were performed using bladder and breast cancer cell lines, rat retinal R28, and human ARPE-19 cells. Results. Two PEDF protein peaks were identified after anion-exchange column chromatography: PEDF-1 eluting with lower ionic strength than PEDF-2. PEDF-1 had higher pI value and lower apparent molecular weight than PEDF-2. Both PEDF forms were glycosylated, bound to heparin, and had identical patterns by limited proteolysis. However, PEDF-2 emerged as being highly potent in lowering cell viability in all tumor cell lines tested, and in inhibiting tumor and ARPE-19 cell migration. In contrast, PEDF-1 minimally affected tumor cell viability and cell migration but protected R28 cells against death caused by serum starvation. Conclusion. Two distinct biochemical forms of PEDF varying in overall charge have distinct biological effects on tumor cell viability and migration. The existence of PEDF forms may explain the multifunctional modality of PEDF.
Collapse
|
28
|
Deshpande M, Notari L, Subramanian P, Notario V, Becerra SP. Inhibition of tumor cell surface ATP synthesis by pigment epithelium-derived factor: implications for antitumor activity. Int J Oncol 2012; 41:219-27. [PMID: 22504705 DOI: 10.3892/ijo.2012.1431] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2011] [Accepted: 01/09/2012] [Indexed: 11/06/2022] Open
Abstract
Recently, we have shown that the antiangiogenic pigment epithelium-derived factor (PEDF) can bind the catalytic β-subunit of F1-ATP synthase and inhibit endothelial cell surface ATP synthase activity. This factor can additionally restrict tumor growth, invasion and metastasis, and can directly induce death on several tumor cell types. Active cell surface ATP synthase is also present in certain tumor cells and its ATP product is considered a stimulus for tumor growth. The present study aimed to elucidate the biological implications of the interactions between the extracellular PEDF and tumor cell surface ATP synthase. Incubation of T24 human urinary bladder carcinoma cells in media containing human recombinant PEDF protein for 48-96 h dramatically decreased cell viability in a concentration-dependent fashion as monitored by real-time cell impedance with a microelectronic system, microscopic imaging and biomarkers of live cells. Intact tumor cells exhibited cell surface ATP synthesis activity, which was inhibited by piceatannol, a specific inhibitor of F1/F0-ATP synthase. Immunoblotting revealed that the β subunit of F1-ATP synthase was present in plasma membrane fractions of these cells. Interestingly, pre-incubation of tumor cells with PEDF inhibited the activity of cell surface ATP synthase in a concentration-dependent fashion. The PEDF-derived peptide 34-mer decreased tumor cell viability and inhibited extracellular ATP synthesis to the same extent as full-length PEDF. Moreover, ATP additions attenuated both the PEDF-mediated decrease in tumor cell viability and the inhibition of endothelial cell tube formation. The results lead to conclude that PEDF is a novel inhibitor of tumor cell surface ATP synthase activity that exhibits a cytotoxic effect on tumor cells, and that the structural determinants for these properties are within the peptide region 34-mer of the PEDF polypeptide. The data strongly suggest a role for the interaction between the 34-mer region of PEDF and tumor cell-surface ATP synthase in promoting tumor cell death.
Collapse
Affiliation(s)
- Monika Deshpande
- Section of Protein Structure and Function, Laboratory of Retinal Cell and Molecular Biology, NEI-NIH, Bethesda, MD, USA
| | | | | | | | | |
Collapse
|
29
|
Farkas L, Gauldie J, Voelkel NF, Kolb M. Pulmonary Hypertension and Idiopathic Pulmonary Fibrosis. Am J Respir Cell Mol Biol 2011; 45:1-15. [DOI: 10.1165/rcmb.2010-0365tr] [Citation(s) in RCA: 149] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
|
30
|
Sekiya A, Okano-Kosugi H, Yamazaki CM, Koide T. Pigment epithelium-derived factor (PEDF) shares binding sites in collagen with heparin/heparan sulfate proteoglycans. J Biol Chem 2011; 286:26364-74. [PMID: 21652703 DOI: 10.1074/jbc.m111.252684] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Pigment epithelium-derived factor (PEDF) is a collagen-binding protein that is abundantly distributed in various tissues, including the eye. It exhibits various biological functions, such as anti-angiogenic, neurotrophic, and neuroprotective activities. PEDF also interacts with extracellular matrix components such as collagen, heparan sulfate proteoglycans (HSPGs), and hyaluronan. The collagen-binding property has been elucidated to be important for the anti-angiogenic activity in vivo (Hosomichi, J., Yasui, N., Koide, T., Soma, K., and Morita, I. (2005) Biochem. Biophys. Res. Commun. 335, 756-761). Here, we investigated the collagen recognition mechanism by PEDF. We first narrowed down candidate PEDF-binding sequences by taking advantage of previously reported structural requirements in collagen. Subsequent searches for PEDF-binding sequences employing synthetic collagen-like peptides resulted in the identification of one of the critical binding sites for PEDF, human α1(I)(929-938) (IKGHRGFSGL). Further analysis revealed that the collagen recognition by PEDF is sequence- and conformation-specific, and the high affinity binding motif is KGXRGFXGL in the triple helix. The PEDF-binding motif significantly overlapped with the heparin/HSPG-binding motif, KGHRG(F/Y). The interaction of PEDF with collagen I was specifically competed with by heparin but not by chondroitin sulfate-C or hyaluronan. The binding sequences for PEDF and heparin/HSPG also overlapped with the covalent cross-linking sites between collagen molecules. These findings imply a functional relationship between PEDF and HSPGs during angiogenesis, and the interaction of these molecules is regulated by collagen modifications.
Collapse
Affiliation(s)
- Atsushi Sekiya
- Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, Tokyo 169-8555, Japan
| | | | | | | |
Collapse
|
31
|
Subramanian P, Crawford SE, Becerra SP. Assays for the antiangiogenic and neurotrophic serpin pigment epithelium-derived factor. Methods Enzymol 2011; 499:183-204. [PMID: 21683255 DOI: 10.1016/b978-0-12-386471-0.00010-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Pigment epithelium-derived factor (PEDF) is a secreted serpin that exhibits a variety of interesting biological activities. The multifunctional PEDF has neurotrophic and antiangiogenic properties, and acts in retinal differentiation, survival, and maintenance. It is also antitumorigenic and antimetastatic, and has stem cell self-renewal properties. It is widely distributed in the human body and exists in abundance in the eye as a soluble extracellular glycoprotein. Its levels are altered in diseases characterized by retinopathies and angiogenesis. Its mechanisms of neuroprotection and angiogenesis are associated with receptor interactions at cell-surface interfaces and changes in protein expression. This serpin lacks demonstrable serine protease inhibitory activity, but has binding affinity to extracellular matrix components and cell-surface receptors. Here we describe purification protocols, methods to quantify PEDF, and determine interactions with specific molecules, as well as neurotrophic and angiogenesis assays for this multifunctional protein.
Collapse
Affiliation(s)
- Preeti Subramanian
- Section of Protein Structure and Function, National Eye Institute, NIH, Bethesda, Maryland, USA
| | | | | |
Collapse
|
32
|
Abstract
Pigment epithelium-derived factor (PEDF) is an endogenously produced glycoprotein with a spectrum of biological roles across diverse pathologies. Recent research has focused on the biochemical properties of PEDF and its associated receptors. This review discusses the recent developments in PEDF biochemistry and how this new knowledge will help progress our understanding of PEDF as a molecular mediator for anti-angiogenesis and -tumorigenesis. Additionally, pathophysiological roles for PEDF in healing and tissue homeostasis are being revealed and our enhanced understanding of the interactions between PEDF and its receptors may yet prove useful in propelling PEDF towards clinical application.
Collapse
Affiliation(s)
- Matthew L Broadhead
- Department of Orthopaedics, St Vincent's Hospital, University of Melbourne, Melbourne, Vic., Australia
| | | | | | | |
Collapse
|
33
|
Konson A, Pradeep S, Seger R. Phosphomimetic Mutants of Pigment Epithelium-Derived Factor with Enhanced Antiangiogenic Activity as Potent Anticancer Agents. Cancer Res 2010; 70:6247-57. [DOI: 10.1158/0008-5472.can-10-0434] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
34
|
Rich RL, Myszka DG. Grading the commercial optical biosensor literature-Class of 2008: 'The Mighty Binders'. J Mol Recognit 2010; 23:1-64. [PMID: 20017116 DOI: 10.1002/jmr.1004] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Optical biosensor technology continues to be the method of choice for label-free, real-time interaction analysis. But when it comes to improving the quality of the biosensor literature, education should be fundamental. Of the 1413 articles published in 2008, less than 30% would pass the requirements for high-school chemistry. To teach by example, we spotlight 10 papers that illustrate how to implement the technology properly. Then we grade every paper published in 2008 on a scale from A to F and outline what features make a biosensor article fabulous, middling or abysmal. To help improve the quality of published data, we focus on a few experimental, analysis and presentation mistakes that are alarmingly common. With the literature as a guide, we want to ensure that no user is left behind.
Collapse
Affiliation(s)
- Rebecca L Rich
- Center for Biomolecular Interaction Analysis, University of Utah, Salt Lake City, UT 84132, USA
| | | |
Collapse
|
35
|
Amaral J, Becerra SP. Effects of human recombinant PEDF protein and PEDF-derived peptide 34-mer on choroidal neovascularization. Invest Ophthalmol Vis Sci 2009; 51:1318-26. [PMID: 19850839 DOI: 10.1167/iovs.09-4455] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
PURPOSE Pigment epithelium-derived factor (PEDF) is a serpin with antiangiogenic properties. Previously, the authors showed that PEDF injected into the subconjunctiva reaches the choroid. Here, they examined the effects of PEDF polypeptide fragments on vessel sprouting and on choroidal neovascularization (CNV) after subconjunctival administration. METHODS Recombinant human PEDF (rhuPEDF) was cleaved at its serpin-exposed loop by limited chymotrypsin proteolysis. Synthetic PEDF peptides 34-mer (Asp(44)-Asn(77)) and 44-mer (Val(78)-Thr(121)) were used. Ex vivo chick aortic vessel sprouting assays were performed. CNV was induced in rats by laser injury of Bruch's membrane. Daily subconjunctival injections (0.01-10 pmol/d protein) were performed for 5 days starting at day of injury or at the seventh day after injury. New vessel volumes were quantified using optical sections of choroid/RPE flat-mounts labeled with isolectin-Ib4. PEDF distribution was evaluated by immunofluorescence of choroid/RPE/retina cross-sections. RESULTS Full-length rhuPEDF, cleaved rhuPEDF, or peptide 34-mer exhibited ex vivo antiangiogenic activity, but peptide 44-mer was inefficient. PEDF immunostaining around CNV lesions diminished after laser injury. Subconjunctival administration of rhuPEDF or 34-mer at 0.1 pmol/d decreased CNV lesion volumes by 52% and 47%, respectively, whereas those of 44-mer were similar to vehicle injections. Doses of 0.1 and 1 pmol/d rhuPEDF decreased fully developed CNV complex volumes by 45% and 50%, respectively, compared with vehicle injections. CONCLUSIONS A functional region for the inhibition of vessel sprouting and CNV resides within the 34-mer region of PEDF. Furthermore, subconjunctival administration of optimal range dosages of rhuPEDF or 34-mer can suppress and regress rat CNV lesions, demonstrating that these agents reach the choroid/RPE complex as functionally active molecules.
Collapse
Affiliation(s)
- Juan Amaral
- Section of Protein Structure and Function, Laboratory of Retinal Cell and Molecular Biology, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892-0608, USA
| | | |
Collapse
|
36
|
Ikeda Y, Yonemitsu Y, Miyazaki M, Kohno RI, Murakami Y, Murata T, Tabata T, Ueda Y, Ono F, Suzuki T, Ageyama N, Terao K, Hasegawa M, Sueishi K, Ishibashi T. Stable retinal gene expression in nonhuman primates via subretinal injection of SIVagm-based lentiviral vectors. Hum Gene Ther 2009; 20:573-9. [PMID: 19257835 DOI: 10.1089/hum.2009.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract Gene therapy may hold promise as a therapeutic approach for the treatment of intractable ocular diseases, including retinitis pigmentosa (RP). Gene transfer vectors that are able to show long-lasting transgene expression in vivo are highly desirable to treat RP; however, there is a dearth of information regarding long-term transgene expression in the eyes of large animals. We previously reported that the simian immunodeficiency virus from African green monkeys (SIVagm)-based lentiviral vector showed efficient, stable, and safe retinal gene transfer, resulting in significant prevention of retinal degeneration by gene transfer of a neurotrophic factor, human pigment epithelium-derived factor (hPEDF), in rodents. Before applying this strategy in a clinical setting, we here assessed the long-lasting transgene expression of our third-generation SIVagm-based lentiviral vectors in the retinal tissue of nonhuman primates. Approximately 20-50 mul of SIV-EGFP (enhanced green fluorescent protein) or SIV-hPEDF was injected into the subretinal space via a glass capillary tube. To detect EGFP expression in the retina, we used a fluorescence fundus camera at various time points after gene transfer. Human PEDF expression was assessed by immunohistochemical analysis, Western blot assay, and enzyme-linked immunosorbent assay. The retinas demonstrated frequent EGFP expression that was preserved for at least 4 years without significant decline. The expression of hPEDF was stable, and occurred mainly in the retinal pigment epithelium. The secreted protein was detected in vitreous and aqueous humor. We thus propose that SIVagm-mediated stable gene transfer might be significantly useful for ocular gene transfer in a clinical setting.
Collapse
Affiliation(s)
- Yasuhiro Ikeda
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Filleur S, Nelius T, de Riese W, Kennedy RC. Characterization of PEDF: a multi-functional serpin family protein. J Cell Biochem 2009; 106:769-75. [PMID: 19180572 DOI: 10.1002/jcb.22072] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Pigment epithelium-derived factor (PEDF) is a 50 kDa secreted glycoprotein that belongs to the non-inhibitory serpin family group. PEDF has been described as a natural angiogenesis inhibitor with neurotrophic and immune-modulation properties; it balances angiogenesis in the eye and blocks tumor progression. The mechanisms underlying most of these events are not completely clear; however, it appears that PEDF acts via multiple high affinity ligands and cell receptors. In this review article, we will summarize the current knowledge on the biochemical properties of PEDF and its receptors, the multimodal activities of PEDF and finally address the therapeutic potential of PEDF in treating angiogenesis-, neurodegeneration- and inflammation-related diseases.
Collapse
Affiliation(s)
- S Filleur
- Department of Urology, Texas Tech University Health Sciences Center, 3601 4th Street, MS 6591, Lubbock, Texas 79430-6591, USA.
| | | | | | | |
Collapse
|
38
|
Bernard A, Gao-Li J, Franco CA, Bouceba T, Huet A, Li Z. Laminin receptor involvement in the anti-angiogenic activity of pigment epithelium-derived factor. J Biol Chem 2009; 284:10480-90. [PMID: 19224861 DOI: 10.1074/jbc.m809259200] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Pigment epithelium-derived factor (PEDF) is a multifunctional protein with neurotrophic, anti-oxidative, and anti-inflammatory properties. It is also one of the most potent endogenous inhibitors of angiogenesis, playing an important role in restricting tumor growth, invasion, and metastasis. Studies show that PEDF binds to cell surface proteins, but little is known about how it exerts its effects. Recently, research identified phospholipase A(2)/nutrin/patatin-like phospholipase domain-containing 2 as one PEDF receptor. To identify other receptors, we performed yeast two-hybrid screening using PEDF as bait and discovered that the non-integrin 37/67-kDa laminin receptor (LR) is another PEDF receptor. Co-immunoprecipitation, His tag pulldown, and surface plasmon resonance assays confirmed the interaction between PEDF and LR. Using the yeast two-hybrid method, we further restricted the LR-interacting domain on PEDF to a 34-amino acid (aa) peptide (aa 44-77) and the PEDF-interacting domain on LR to a 91-aa fragment (aa 120-210). A 25-mer peptide named P46 (aa 46-70), derived from 34-mer, interacts with LR in surface plasmon resonance assays and binds to endothelial cell (EC) membranes. This peptide induces EC apoptosis and inhibits EC migration, tube-like network formation in vitro, and retinal angiogenesis ex vivo, like PEDF. Our results suggest that LR is a real PEDF receptor that mediates PEDF angiogenesis inhibition.
Collapse
Affiliation(s)
- Adrien Bernard
- Université Pierre et Marie Curie, Univerisité Paris 06, UR4, Aging, Stress and Inflammation and Institut Fédératif de Recherche 83, 75252 Paris, France
| | | | | | | | | | | |
Collapse
|