51
|
Zhang T, Yin P, Zhang Z, Xu B, Che D, Dai Z, Dong C, Jiang P, Hong H, Yang Z, Zhou T, Shao J, Xu Z, Yang X, Gao G. Deficiency of pigment epithelium-derived factor in nasopharyngeal carcinoma cells triggers the epithelial-mesenchymal transition and metastasis. Cell Death Dis 2017; 8:e2838. [PMID: 28569772 PMCID: PMC5520876 DOI: 10.1038/cddis.2017.114] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 02/18/2017] [Accepted: 02/20/2017] [Indexed: 01/01/2023]
Abstract
Distant metastasis is the primary cause of nasopharyngeal carcinoma (NPC) treatment failure while epithelial-mesenchymal transition (EMT) is the critical process of NPC invasion and metastasis. However, tumor-suppressor genes involved in the EMT and metastasis of NPC have not been explored clearly compared with the oncogenes. In the present study, the expression of pigment epithelium-derived factor (PEDF), a potent endogenous antitumor factor, was diminished in human NPC tissues and associated with clinicopathological and EMT features. The knockdown of PEDF induced EMT in lower metastatic NPC cell lines and overexpression of PEDF restored epithelial phenotype in higher metastatic NPC cell lines with typical EMT. The inhibition of PEDF mediated NPC cell spontaneous metastasis in vivo. LRP6/GSK3β/β-catenin signal pathway rather than AKT/GSK3β pathway was involved in the effects of PEDF on EMT. The expression of PEDF was directly downregulated by elevated miR-320c in NPC. In conclusion, our findings indicate for the first time that PEDF functions as tumor-suppressor gene in the occurrence of EMT and metastasis in NPC. PEDF could serve as a promising candidate for NPC diagnosis, prognosis and treatment.
Collapse
Affiliation(s)
- Ting Zhang
- Program of Molecular Medicine, Affiliated Guangzhou Women and Children's Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China.,Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China.,Department of Laboratory Medicine, Guangzhou First People's Hospital, Guangzhou Medical University, Guangzhou 510180, China
| | - Ping Yin
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Zichen Zhang
- Department of Molecular Diagnostics, Sun Yat-sen University Cancer Center, Guangzhou 510160, China
| | - Banglao Xu
- Department of Laboratory Medicine, Guangzhou First People's Hospital, Guangzhou Medical University, Guangzhou 510180, China
| | - Di Che
- Program of Molecular Medicine, Affiliated Guangzhou Women and Children's Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China.,Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Zhiyu Dai
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Chang Dong
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Ping Jiang
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Honghai Hong
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China.,Department of Clinical Laboratory, Third Affiliated Hospital of Guangzhou Medical University, Guangzhou 510150, China
| | - Zhonghan Yang
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Ti Zhou
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Jianyong Shao
- Department of Molecular Diagnostics, Sun Yat-sen University Cancer Center, Guangzhou 510160, China
| | - Zumin Xu
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China.,Cancer Center, Affiliated Hospital of Guangdong Medical College, Zhanjiang 524001, China
| | - Xia Yang
- Program of Molecular Medicine, Affiliated Guangzhou Women and Children's Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China.,Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China.,Guangdong Engineering &Technology Research Center for Gene Manipulation and Biomacromolecular Products (Sun Yat-sen University), Guangzhou 510080, China
| | - Guoquan Gao
- Program of Molecular Medicine, Affiliated Guangzhou Women and Children's Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China.,Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China.,China Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Ministry of Education, Guangzhou 510080, China
| |
Collapse
|
52
|
Transgenic expression of a canonical Wnt inhibitor, kallistatin, is associated with decreased circulating CD19 + B lymphocytes in the peripheral blood. Int J Hematol 2017; 105:748-757. [PMID: 28299632 DOI: 10.1007/s12185-017-2205-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 02/21/2017] [Accepted: 02/28/2017] [Indexed: 12/28/2022]
Abstract
Members of the family of serine proteinase inhibitors, such as kallistatin, have been shown to inhibit canonical Wnt-TCF/LEF-β-catenin signaling via their interactions with the Wnt co-receptor LRP6. Yet the effects of transgenic overexpression of anti-Wnt serpins on hematopoiesis and lymphopoiesis are not well known. We studied the effects of human kallistatin (SERPINA4) on Wnt reporter activity in various cell types throughout the hematopoietic system and associated impacts on circulating white blood cell profiles. Transgenic overexpression of kallistatin suppressed Wnt-TCF/LEF-β-catenin signaling in bone marrow, as demonstrated using a Wnt reporter mouse. Further, kallistatin overexpression and treatment were associated with reduced Wnt-TCF/LEF-β-catenin activity in CD34+ c-kit+ bone marrow cells and CD19+ B lymphocytes, with reduced levels of these populations in bone marrow and peripheral circulation, respectively. The presence of CD3+CD4+, CD3+CD8+, and CD3- NK1.1+ T lymphocytes were not significantly affected. Our data suggest that overexpression of kallistatin interferes with lymphopoiesis, ultimately impacting the level of circulating CD19+ B lymphocytes.
Collapse
|
53
|
Kang H, Aryal A C S, Marini JC. Osteogenesis imperfecta: new genes reveal novel mechanisms in bone dysplasia. Transl Res 2017; 181:27-48. [PMID: 27914223 DOI: 10.1016/j.trsl.2016.11.005] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 11/04/2016] [Accepted: 11/07/2016] [Indexed: 12/20/2022]
Abstract
Osteogenesis imperfecta (OI) is a skeletal dysplasia characterized by fragile bones and short stature and known for its clinical and genetic heterogeneity which is now understood as a collagen-related disorder. During the last decade, research has made remarkable progress in identifying new OI-causing genes and beginning to understand the intertwined molecular and biochemical mechanisms of their gene products. Most cases of OI have dominant inheritance. Each new gene for recessive OI, and a recently identified gene for X-linked OI, has shed new light on its (often previously unsuspected) function in bone biology. Here, we summarize the literature that has contributed to our current understanding of the pathogenesis of OI.
Collapse
Affiliation(s)
- Heeseog Kang
- Section on Heritable Disorders of Bone and Extracellular Matrix, NICHD, NIH, Bethesda, Md
| | - Smriti Aryal A C
- Section on Heritable Disorders of Bone and Extracellular Matrix, NICHD, NIH, Bethesda, Md
| | - Joan C Marini
- Section on Heritable Disorders of Bone and Extracellular Matrix, NICHD, NIH, Bethesda, Md.
| |
Collapse
|
54
|
Pigment epithelium-derived factor attenuates myocardial fibrosis via inhibiting Endothelial-to-Mesenchymal Transition in rats with acute myocardial infarction. Sci Rep 2017; 7:41932. [PMID: 28167820 PMCID: PMC5294634 DOI: 10.1038/srep41932] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Accepted: 01/03/2017] [Indexed: 02/06/2023] Open
Abstract
Endothelial mesenchymal transition (EndMT) plays a critical role in the pathogenesis and progression of interstitial and perivascular fibrosis after acute myocardial infarction (AMI). Pigment epithelium-derived factor (PEDF) is shown to be a new therapeutic target owing to its protective role in cardiovascular disease. In this study, we tested the hypothesis that PEDF is an endogenous inhibitor of EndMT and represented a novel mechanism for its protective effects against overactive cardiac fibrosis after AMI. Masson’s trichrome (MTC) staining and picrosirius red staining revealed decreased interstitial and perivascular fibrosis in rats overexpressing PEDF. The protective effect of PEDF against EndMT was confirmed by co-labeling of cells with the myofibroblast and endothelial cell markers. In the endothelial cells of microvessels in the ischemic myocardium, the inhibitory effect of PEDF against nuclear translocation of β-catenin was observed through confocal microscopic imaging. The correlation between antifibrotic effect of PEDF and inactivation of β-catenin was confirmed by co-transfecting cells with lentivirus carrying PEDF or PEDF RNAi and plasmids harboring β-catenin siRNA(r) or constitutive activation of mutant β-catenin. Taken together, these results establish a novel finding that PEDF could inhibit EndMT related cardiac fibrosis after AMI by a mechanism dependent on disruption of β-catenin activation and translocation.
Collapse
|
55
|
Ma S, Yao S, Tian H, Jiao P, Yang N, Zhu P, Qin S. Pigment epithelium-derived factor alleviates endothelial injury by inhibiting Wnt/β-catenin pathway. Lipids Health Dis 2017; 16:31. [PMID: 28173817 PMCID: PMC5297210 DOI: 10.1186/s12944-017-0407-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 01/03/2017] [Indexed: 11/10/2022] Open
Abstract
Background Oxidized low-density lipoprotein (ox-LDL) can induce endothelial injury and plays a vital role in the procession and development of atherosclerosis. Little is known regarding whether Wnt/β-catenin pathway is involved in ox-LDL-induced endothelial injury or whether it further promotes atherosclerosis via increased oxidative stress. This study aimed to investigate the role of Wnt/β-catenin pathway in ox-LDL-induced vascular endothelial injury and determine whether pigment epithelium-derived factor (PEDF) could alleviate ox-LDL-induced endothelial injury by inhibiting Wnt/β-catenin pathway. Methods Injury of human umbilical vein endothelial cells (HUVECs) was evaluated with an MTT assay, by monitoring lactate dehydrogenase (LDH) release and determining the apoptotic ratio. The expression of β-catenin (non-phosphorylated-β-catenin), disheveled-1 (Dvl-1) and Cyclin D1 was analyzed with western blotting and quantitative real-time PCR. Oxidative stress status was assessed by measuring the levels of reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD) and nitric oxide (NO). Results Exposure of HUVECs to ox-LDL led to a decrease in cell viability and an increase in LDH release and apoptosis with concomitant enhancement of oxidative stress, as assessed by increased ROS and MDA generation, as well as decreased SOD activity and NO levels. Similar to lithium chloride (LiCl, a Wnt/β-catenin pathway activator), ox-LDL up-regulated the expression of β-catenin, Dvl-1 and Cyclin D1, markers of Wnt/β-catenin pathway activation. However, ox-LDL-induced activation of Wnt/β-catenin pathway, as well as ox-LDL-induced cell injury and oxidative stress, were synergistically promoted by LiCl and mitigated by Dickkopf 1 (DKK-1), an inhibitor of Wnt/β-catenin pathway. Additionally, ox-LDL-induced HUVEC injury and apoptosis, oxidative stress and activation of Wnt/β-catenin pathway were suppressed by PEDF, while they were further strengthened by a small interfering RNA of PEDF. Conclusion Wnt/β-catenin pathway may mediate ox-LDL-induced endothelial injury via oxidative stress, and PEDF ameliorates endothelial injury by suppressing Wnt/β-catenin pathway and subsequently reducing oxidative stress. Electronic supplementary material The online version of this article (doi:10.1186/s12944-017-0407-8) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Shouyuan Ma
- Department of Geriatric Cardiology, Chinese PLA General Hospital, Beijing, 100853, China
| | - Shutong Yao
- Key Laboratory of Atherosclerosis in Universities of Shandong and Institute of Atherosclerosis, Taishan Medical University, Taian, Shandong, 271000, China.,College of Basic Medical Sciences, Taishan Medical University, Taian, Shandong, 271000, China
| | - Hua Tian
- Key Laboratory of Atherosclerosis in Universities of Shandong and Institute of Atherosclerosis, Taishan Medical University, Taian, Shandong, 271000, China
| | - Peng Jiao
- Key Laboratory of Atherosclerosis in Universities of Shandong and Institute of Atherosclerosis, Taishan Medical University, Taian, Shandong, 271000, China
| | - Nana Yang
- Key Laboratory of Atherosclerosis in Universities of Shandong and Institute of Atherosclerosis, Taishan Medical University, Taian, Shandong, 271000, China
| | - Ping Zhu
- Department of Geriatric Cardiology, Chinese PLA General Hospital, Beijing, 100853, China.
| | - Shucun Qin
- Key Laboratory of Atherosclerosis in Universities of Shandong and Institute of Atherosclerosis, Taishan Medical University, Taian, Shandong, 271000, China.
| |
Collapse
|
56
|
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
|
57
|
Cheng R, Ding L, He X, Takahashi Y, Ma JX. Interaction of PPARα With the Canonic Wnt Pathway in the Regulation of Renal Fibrosis. Diabetes 2016; 65:3730-3743. [PMID: 27543085 PMCID: PMC5127249 DOI: 10.2337/db16-0426] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 09/04/2016] [Indexed: 01/02/2023]
Abstract
Peroxisome proliferator-activated receptor-α (PPARα) displays renoprotective effects with an unclear mechanism. Aberrant activation of the canonical Wnt pathway plays a key role in renal fibrosis. Renal levels of PPARα were downregulated in both type 1 and type 2 diabetes models. The PPARα agonist fenofibrate and overexpression of PPARα both attenuated the expression of fibrotic factors, and suppressed high glucose-induced or Wnt3a-induced Wnt signaling in renal cells. Fenofibrate inhibited Wnt signaling in the kidney of diabetic rats. A more renal prominent activation of Wnt signaling was detected both in PPARα-/- mice with diabetes or obstructive nephropathy and in PPARα-/- tubular cells treated with Wnt3a. PPARα did not block the transcriptional activity of β-catenin induced by a constitutively active mutant of lipoprotein receptor-related protein 6 (LRP6) or β-catenin. LRP6 stability was decreased by overexpression of PPARα and increased in PPARα-/- tubular cells, suggesting that PPARα interacts with Wnt signaling at the Wnt coreceptor level. 4-Hydroxynonenal-induced reactive oxygen species production, which resulted in LRP6 stability, was suppressed by overexpression of PPARα and dramatically enhanced in PPARα-/- tubular cells. Diabetic PPARα-/- mice showed more prominent NADPH oxidase-4 overexpression compared with diabetic wild-type mice, suggesting that the inhibitory effect of PPARα on Wnt signaling may be ascribed to its antioxidant activity. These observations identified a novel interaction between PPARα and the Wnt pathway, which is responsible, at least partially, for the therapeutic effects of fenofibrate on diabetic nephropathy.
Collapse
Affiliation(s)
- Rui Cheng
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Lexi Ding
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Xuemin He
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Yusuke Takahashi
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Jian-Xing Ma
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| |
Collapse
|
58
|
He X, Cheng R, Park K, Benyajati S, Moiseyev G, Sun C, Olson LE, Yang Y, Eby BK, Lau K, Ma JX. Pigment epithelium-derived factor, a noninhibitory serine protease inhibitor, is renoprotective by inhibiting the Wnt pathway. Kidney Int 2016; 91:642-657. [PMID: 27914705 DOI: 10.1016/j.kint.2016.09.036] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 08/23/2016] [Accepted: 09/22/2016] [Indexed: 11/24/2022]
Abstract
Pigment epithelium-derived factor (PEDF) expression is downregulated in the kidneys of diabetic rats, and delivery of PEDF suppressed renal fibrotic factors in these animals. PEDF has multiple functions including anti-angiogenic, anti-inflammatory and antifibrotic activities. Since the mechanism underlying its antifibrotic effect remains unclear, we studied this in several murine models of renal disease. Renal PEDF levels were significantly reduced in genetic models of type 1 and type 2 diabetes (Akita and db/db, respectively), negatively correlating with Wnt signaling activity in the kidneys. In unilateral ureteral obstruction, an acute renal injury model, there were significant decreases of renal PEDF levels. The kidneys of PEDF knockout mice with ureteral obstruction displayed exacerbated expression of fibrotic and inflammatory factors, oxidative stress, tubulointerstitial fibrosis, and tubule epithelial cell apoptosis, compared to the kidneys of wild-type mice with obstruction. PEDF knockout enhanced Wnt signaling activation induced by obstruction, while PEDF inhibited the Wnt pathway-mediated fibrosis in primary renal proximal tubule epithelial cells. Additionally, oxidative stress was aggravated in renal proximal tubule epithelial cells isolated from knockout mice and suppressed by PEDF treatment of renal proximal tubule epithelial cells. PEDF also reduced oxidation-induced apoptosis in renal proximal tubule epithelial cells. Thus, the renoprotective effects of PEDF are mediated, at least partially, by inhibition of the Wnt pathway. Hence, restoration of renal PEDF levels may have therapeutic potential for renal fibrosis.
Collapse
Affiliation(s)
- Xuemin He
- Department of Physiology, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Rui Cheng
- Department of Physiology, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Kyoungmin Park
- Joslin Diabetes Center, Harvard Medical School, Harvard University, Boston, Massachusetts, USA
| | - Siribhinya Benyajati
- Department of Physiology, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Gennadiy Moiseyev
- Department of Physiology, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Chengyi Sun
- Department of Cell Biology, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA; Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Lorin E Olson
- Department of Cell Biology, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA; Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Yanhui Yang
- Key Laboratory of Hormones and Development, Tianjin Metabolic Diseases Hospital and Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China
| | - Bonnie K Eby
- Section of Nephrology, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Kai Lau
- Section of Nephrology, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Jian-Xing Ma
- Department of Physiology, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA.
| |
Collapse
|
59
|
Venkatadri R, Iyer AKV, Ramesh V, Wright C, Castro CA, Yakisich JS, Azad N. MnTBAP Inhibits Bleomycin-Induced Pulmonary Fibrosis by Regulating VEGF and Wnt Signaling. J Cell Physiol 2016; 232:506-516. [PMID: 27649046 DOI: 10.1002/jcp.25608] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 09/19/2016] [Indexed: 01/02/2023]
Abstract
Cellular oxidative stress is implicated not only in lung injury but also in contributing to the development of pulmonary fibrosis. We demonstrate that a cell-permeable superoxide dismutase (SOD) mimetic and peroxynitrite scavenger, manganese (III) tetrakis (4-benzoic acid) porphyrin chloride (MnTBAP) significantly inhibited bleomycin-induced fibrogenic effects both in vitro and in vivo. Further investigation into the underlying mechanisms revealed that MnTBAP targets canonical Wnt and non-canonical Wnt/Ca2+ signaling pathways, both of which were upregulated by bleomycin treatment. The effect of MnTBAP on canonical Wnt signaling was significant in vivo but inconclusive in vitro and the non-canonical Wnt/Ca2+ signaling pathway was observed to be the predominant pathway regulated by MnTBAP in bleomycin-induced pulmonary fibrosis. Furthermore, we show that the inhibitory effects of MnTBAP involve regulation of VEGF which is upstream of the Wnt signaling pathway. Overall, the data show that the superoxide scavenger MnTBAP attenuates bleomycin-induced pulmonary fibrosis by targeting VEGF and Wnt signaling pathways. J. Cell. Physiol. 232: 506-516, 2017. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Rajkumar Venkatadri
- Department of Pharmaceutical Sciences, Hampton University, Hampton, Virginia
| | | | - Vani Ramesh
- Department of Obstetrics and Gynecology, The Jones Institute for Reproductive Medicine, Eastern Virginia Medical School, Norfolk, Virginia
| | - Clayton Wright
- Department of Pharmaceutical Sciences, Hampton University, Hampton, Virginia
| | - Carlos A Castro
- Magee Women's Research Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Juan S Yakisich
- Department of Pharmaceutical Sciences, Hampton University, Hampton, Virginia
| | - Neelam Azad
- Department of Pharmaceutical Sciences, Hampton University, Hampton, Virginia
| |
Collapse
|
60
|
Gong J, Belinsky G, Sagheer U, Zhang X, Grippo PJ, Chung C. Pigment Epithelium-derived Factor (PEDF) Blocks Wnt3a Protein-induced Autophagy in Pancreatic Intraepithelial Neoplasms. J Biol Chem 2016; 291:22074-22085. [PMID: 27557659 DOI: 10.1074/jbc.m116.729962] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Indexed: 02/05/2023] Open
Abstract
An increase in autophagy characterizes pancreatic carcinogenesis, but the signals that regulate this process are incompletely understood. Because canonical Wnt/β-catenin signaling is necessary for the transition from early to advanced pancreatic intraepithelial neoplasia (PanIN) lesions, we assessed whether Wnt ligands and endogenous inhibitors of Wnt signaling modulate autophagy. In this study, canonical Wnt3a ligand induced autophagy markers and vacuoles in murine PanIN cells. Furthermore, pigment epithelium-derived factor (PEDF), a secreted glycoprotein known for its anti-tumor properties, blocked Wnt3a-directed induction of autophagy proteins. Autophagy inhibition was complemented by reciprocal regulation of the oxidative stress enzymes, superoxide dismutase 2 (SOD2) and catalase. Transcriptional control of Sod2 expression was mediated by PEDF-induced NFκB nuclear translocation. PEDF-dependent SOD2 expression in PanIN lesions was recapitulated in a murine model of PanIN formation where PEDF was deleted. In human PanIN lesions, co-expression of PEDF and SOD2 was observed in the majority of early PanIN lesions (47/50, 94%), whereas PEDF and SOD2 immunolocalization in high-grade human PanIN-2/3 was uncommon (7/50, 14%). These results indicate that PEDF regulates autophagy through coordinate Wnt signaling blockade and NFκB activation.
Collapse
Affiliation(s)
| | | | - Usman Sagheer
- the Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Xuchen Zhang
- the Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516 Pathology, Yale University School of Medicine, New Haven, Connecticut 06520
| | - Paul J Grippo
- the Department of Medicine, University of Illinois School of Medicine, Chicago, Illinois 60612, and
| | - Chuhan Chung
- From the Departments of Medicine and the Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| |
Collapse
|
61
|
SERPINE2/Protease Nexin-1 in vivo multiple functions: Does the puzzle make sense? Semin Cell Dev Biol 2016; 62:160-169. [PMID: 27545616 DOI: 10.1016/j.semcdb.2016.08.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 08/17/2016] [Accepted: 08/17/2016] [Indexed: 11/21/2022]
Abstract
Cultures of glial cells and fibroblasts allowed and lead to the identification SERPINE2/Protease Nexin-1 (SERPINE2/PN-1). Cellular, biochemical, immunological and molecular characterization substantiated its variable expression in many organs as a function of development, adult stages, pathological situations or following injury. It is not a circulating serpin, but as other members of the family, its target specificity is influenced by components of the extracellular matrix. The challenges are to identify where and when SERPINE2/PN-1 modulatory action becomes crucial or even possibly specific in a mosaic of feasible in vivo impacts. Data providing correlations are not sufficient to satisfy this aim. Genetically modified mice, or tissue derived thereof, provide interesting in vivo models to identify and study the relevance of this serpin. This review will highlight sometimes-intriguing results indicating a crucial impact of SERPINE2/PN-1, especially in the vasculature, the nervous system or the behavior of cancer cells in vivo. Data presently available will be discussed in an attempt to define general trends in the diversity of SERPINE2/PN-1 modes of action in vivo.
Collapse
|
62
|
Moran EP, Wang Z, Chen J, Sapieha P, Smith LEH, Ma JX. Neurovascular cross talk in diabetic retinopathy: Pathophysiological roles and therapeutic implications. Am J Physiol Heart Circ Physiol 2016; 311:H738-49. [PMID: 27473938 DOI: 10.1152/ajpheart.00005.2016] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 07/18/2016] [Indexed: 12/19/2022]
Abstract
Diabetic retinopathy (DR) is the leading cause of blindness in the working-age population in developed countries, and its prevalence will increase as the global incidence of diabetes grows exponentially. DR begins with an early nonproliferative stage in which retinal blood vessels and neurons degenerate as a consequence of chronic hyperglycemia, resulting in vasoregression and persistent retinal ischemia, metabolic disequilibrium, and inflammation. This is conducive to overcompensatory pathological neovascularization associated with advanced proliferative DR. Although DR is considered a microvascular complication, the retinal microvasculature is intimately associated with and governed by neurons and glia; neurodegeneration, neuroinflammation, and dysregulation of neurovascular cross talk are responsible in part for vascular abnormalities in both early nonproliferative DR and advanced proliferative DR. Neuronal activity directly regulates microvascular dilation and blood flow in the process of neurovascular coupling. Retinal neurons also secrete guidance cues in response to injury, ischemia, or metabolic stress that may either promote or suppress vascular outgrowth, either alleviating or exacerbating DR, contingent on the stage of disease and retinal microenvironment. Neurodegeneration, impaired neurovascular coupling, and dysregulation of neuronal guidance cues are key events in the pathogenesis of DR, and correcting these events may prevent or delay development of advanced DR. The review discusses the mechanisms of neurovascular cross talk and its dysregulation in DR, and their potential therapeutic implications.
Collapse
Affiliation(s)
- Elizabeth P Moran
- Depatment of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; Harold Hamm Diabetes Center, Oklahoma City, Oklahoma
| | - Zhongxiao Wang
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts; and
| | - Jing Chen
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts; and
| | - Przemyslaw Sapieha
- Departments of Ophthalmology, Biochemistry & Molecular Medicine, Maisonneuve-Rosemont Hospital Research Centre, University of Montreal, Montreal, Quebec, Canada
| | - Lois E H Smith
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts; and
| | - Jian-Xing Ma
- Depatment of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; Harold Hamm Diabetes Center, Oklahoma City, Oklahoma;
| |
Collapse
|
63
|
Belinsky GS, Ward L, Chung C. Pigment epithelium-derived factor (PEDF) normalizes matrix defects in iPSCs derived from Osteogenesis imperfecta Type VI. Rare Dis 2016; 4:e1212150. [PMID: 27579219 PMCID: PMC4986704 DOI: 10.1080/21675511.2016.1212150] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 06/14/2016] [Accepted: 07/06/2016] [Indexed: 01/28/2023] Open
Abstract
Osteogenesis imperfecta (OI) Type VI is characterized by a defect in bone mineralization, which results in multiple fractures early in life. Null mutations in the PEDF gene, Serpinf1, are the cause of OI VI. Whether PEDF restoration in a murine model of OI Type VI could improve bone mass and function was previously unknown. In Belinsky et al, we provided evidence that PEDF delivery enhanced bone mass and improved parameters of bone function in vivo. Further, we demonstrated that PEDF temporally inhibits Wnt signaling to enhance osteoblast differentiation. Here, we demonstrate that generation of induced pluripotent stem cells (iPSCs) from a PEDF null patient provides additional evidence for PEDF's role in regulating extracellular matrix proteins secreted from osteoblasts. PEDF null iPSCs have marked abnormalities in secreted matrix proteins, capturing a key feature of human OI Type VI, which were normalized by exogenous PEDF. Lastly, we place our recent findings within the broader context of PEDF biology and the developmental signaling pathways that are implicated in its actions.
Collapse
Affiliation(s)
- Glenn S Belinsky
- Department of Medicine, Yale University School of Medicine , New Haven, CT, USA
| | - Leanne Ward
- Children's Hospital of Eastern Ontario , Ottawa, Canada
| | - Chuhan Chung
- Department of Medicine, Yale University School of Medicine, New Haven, CT, USA; VA CT Healthcare System, West Haven, CT, USA
| |
Collapse
|
64
|
Shih SC, Ho TC, Chen SL, Tsao YP. Pigment Epithelium Derived Factor Peptide Protects Murine Hepatocytes from Carbon Tetrachloride-Induced Injury. PLoS One 2016; 11:e0157647. [PMID: 27384427 PMCID: PMC4934881 DOI: 10.1371/journal.pone.0157647] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 06/02/2016] [Indexed: 12/31/2022] Open
Abstract
Fibrogenesis is induced by repeated injury to the liver and reactive regeneration and leads eventually to liver cirrhosis. Pigment epithelium derived factor (PEDF) has been shown to prevent liver fibrosis induced by carbon tetrachloride (CCl4). A 44 amino acid domain of PEDF (44-mer) was found to have a protective effect against various insults to several cell types. In this study, we investigated the capability of synthetic 44-mer to protect against liver injury in mice and in primary cultured hepatocytes. Acute liver injury, induced by CCl4, was evident from histological changes, such as cell necrosis, inflammation and apoptosis, and a concomitant reduction of glutathione (GSH) and GSH redox enzyme activities in the liver. Intraperitoneal injection of the 44-mer into CCl4-treated mice abolished the induction of AST and ALT and markedly reduced histological signs of liver injury. The 44-mer treatment can reduce hepatic oxidative stress as evident from lower levels of lipid hydroperoxide, and higher levels of GSH. CCl4 caused a reduction of Bcl-xL, PEDF and PPARγ, which was markedly restored by the 44-mer treatment. Consequently, the 44-mer suppressed liver fibrosis induced by repeated CCl4 injury. Furthermore, our observations in primary culture of rat hepatocytes showed that PEDF and the 44-mer protected primary rat hepatocytes against apoptosis induced by serum deprivation and TGF-β1. PEDF/44-mer induced cell protective STAT3 phosphorylation. Pharmacological STAT3 inhibition prevented the antiapoptotic action of PEDF/44-mer. Among several PEDF receptor candidates that may be responsible for hepatocyte protection, we demonstrated that PNPLA2 was essential for PEDF/44-mer-mediated STAT3 phosphorylation and antiapoptotic activity by using siRNA to selectively knockdown PNPLA2. In conclusion, the PEDF 44-mer protects hepatocytes from single and repeated CCl4 injury. This protective effect may stem from strengthening the counter oxidative stress capacity and induction of hepatoprotective factors.
Collapse
Affiliation(s)
- Shou-Chuan Shih
- Mackay Medical College, New Taipei City, Taiwan
- Department of Internal Medicine, Mackay Memorial Hospital, Taipei, Taiwan
- * E-mail: (SCS); (YPT)
| | - Tsung-Chuan Ho
- Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan
| | - Show-Li Chen
- Department of Microbiology, School of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yeou-Ping Tsao
- Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan
- Department of Ophthalmology, Mackay Memorial Hospital, Taipei, Taiwan
- * E-mail: (SCS); (YPT)
| |
Collapse
|
65
|
Loegl J, Nussbaumer E, Hiden U, Majali-Martinez A, Ghaffari-Tabrizi-Wizy N, Cvitic S, Lang I, Desoye G, Huppertz B. Pigment epithelium-derived factor (PEDF): a novel trophoblast-derived factor limiting feto-placental angiogenesis in late pregnancy. Angiogenesis 2016; 19:373-88. [PMID: 27278471 PMCID: PMC4930480 DOI: 10.1007/s10456-016-9513-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 05/13/2016] [Indexed: 12/24/2022]
Abstract
The rapidly expanding feto-placental vasculature needs tight control by paracrine and endocrine mechanisms. Here, we focused on paracrine influence by trophoblast, the placental epithelium. We aimed to identify differences in regulation of feto-placental angiogenesis in early versus late pregnancy. To this end, the effect of conditioned media (CM) from early and late pregnancy human trophoblast was tested on network formation, migration and proliferation of human feto-placental endothelial cells. Only CM of late pregnancy trophoblast reduced network formation and migration. Screening of trophoblast transcriptome for anti-angiogenic candidates identified pigment epithelium-derived factor (PEDF) with higher expression and protein secretion in late pregnancy trophoblast. Addition of a PEDF-neutralizing antibody restored the anti-angiogenic effect of CM from late pregnancy trophoblast. Notably, human recombinant PEDF reduced network formation only in combination with VEGF. Also in the CAM assay, the combination of PEDF with VEGF reduced branching of vessels below control levels. Analysis of phosphorylation of ERK1/2 and FAK, two key players in VEGF-induced proliferation and migration, revealed that PEDF altered VEGF signaling, while PEDF alone did not affect phosphorylation of ERK1/2 and FAK. These data suggest that the trophoblast-derived anti-angiogenic molecule PEDF is involved in restricting growth and expansion of the feto-placental endothelium predominantly in late pregnancy and targets to modulate the intracellular effect of VEGF.
Collapse
Affiliation(s)
- Jelena Loegl
- Department of Obstetrics and Gynecology, Medical University of Graz, Graz, Austria.,Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - Erika Nussbaumer
- Department of Obstetrics and Gynecology, Medical University of Graz, Graz, Austria
| | - Ursula Hiden
- Department of Obstetrics and Gynecology, Medical University of Graz, Graz, Austria.
| | | | | | - Silvija Cvitic
- Department of Obstetrics and Gynecology, Medical University of Graz, Graz, Austria.,Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - Ingrid Lang
- Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - Gernot Desoye
- Department of Obstetrics and Gynecology, Medical University of Graz, Graz, Austria
| | - Berthold Huppertz
- Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| |
Collapse
|
66
|
Belinsky GS, Sreekumar B, Andrejecsk JW, Saltzman WM, Gong J, Herzog RI, Lin S, Horsley V, Carpenter TO, Chung C. Pigment epithelium-derived factor restoration increases bone mass and improves bone plasticity in a model of osteogenesis imperfecta type VI via Wnt3a blockade. FASEB J 2016; 30:2837-48. [PMID: 27127101 DOI: 10.1096/fj.201500027r] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 04/18/2016] [Indexed: 12/23/2022]
Abstract
Null mutations in for pigment epithelium-derived factor (PEDF), the protein product of the SERPINF1 gene, are the cause of osteogenesis imperfecta (OI) type VI. The PEDF-knockout (KO) mouse captures crucial elements of the human disease, including diminished bone mineralization and propensity to fracture. Our group and others have demonstrated that PEDF directs human mesenchymal stem cell (hMSC) commitment to the osteoblast lineage and modulates Wnt/β-catenin signaling, a major regulator of bone development; however, the ability of PEDF to restore bone mass in a mouse model of OI type VI has not been determined. In this study, PEDF delivery increased trabecular bone volume/total volume by 52% in 6-mo-old PEDF-KO mice but not in wild-type mice. In young (19-d-old) PEDF-KO mice, PEDF restoration increased bone volume fraction by 35% and enhanced biomechanical parameters of bone plasticity. A Wnt-green fluorescent protein reporter demonstrated dynamic changes in Wnt/β-catenin signaling characterized by early activation and marked suppression during terminal differentiation of hMSCs. Continuous Wnt3a exposure impeded mineralization of hMSCs, whereas the combination of Wnt3a and PEDF potentiated mineralization. Interrogation of the PEDF sequence identified a conserved motif found in other Wnt modulators, such as the dickkopf proteins. Mutation of a single amino acid on a 34-mer PEDF peptide increased mineralization of hMSC cultures compared with the native peptide sequence. These results indicate that PEDF counters Wnt signaling to allow for osteoblast differentiation and provides a mechanistic insight into how the PEDF null state results in OI type VI.-Belinsky, G. S., Sreekumar, B., Andrejecsk, J. W., Saltzman, W. M., Gong, J., Herzog, R. I., Lin, S., Horsley, V., Carpenter, T. O., Chung, C. Pigment epithelium-derived factor restoration increases bone mass and improves bone plasticity in a model of osteogenesis imperfecta type VI via Wnt3a blockade.
Collapse
Affiliation(s)
- Glenn S Belinsky
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Bharath Sreekumar
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Jillian W Andrejecsk
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA
| | - W Mark Saltzman
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA
| | - Jingjing Gong
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Raimund I Herzog
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Samantha Lin
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut, USA
| | - Valerie Horsley
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut, USA
| | - Thomas O Carpenter
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Chuhan Chung
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut, USA; Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut, USA
| |
Collapse
|
67
|
miR-148a is a downstream effector of X-box-binding protein 1 that silences Wnt10b during adipogenesis of 3T3-L1 cells. Exp Mol Med 2016; 48:e226. [PMID: 27055562 PMCID: PMC4855278 DOI: 10.1038/emm.2016.3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 12/17/2015] [Accepted: 12/22/2015] [Indexed: 01/21/2023] Open
Abstract
Wnt10b, an endogenous inhibitor of adipogenesis, maintains preadipocytes in an undifferentiated state by suppressing adipogenic transcription factors. We have previously demonstrated that Wnt10b transcription during adipogenesis is negatively regulated by X-box-binding protein 1 (XBP1), an important transcription factor of the unfolded protein response. In this report, we demonstrate that XBP1s can directly induce the transcription of microRNA-148a, which in turn mediates the silencing of Wnt10b mRNA during adipogenic differentiation of 3T3-L1 cells. Stability of Wnt10b mRNA was found to be significantly increased by knockdown of XBP1s. Using computational algorithms, a set of microRNAs was predicted to bind Wnt10b mRNA, of which microRNA-148a was selected as a potential target for XBP1s. Our results revealed that microRNA-148a could bind to the 3′UTR of Wnt10b mRNA. Its ectopic expression significantly suppressed both Wnt10b expression and β-catenin activity. When we altered the expression of XBP1 in 3T3-L1 cells, microRNA-148a levels changed accordingly. A potential XBP1 response element was found in the promoter region of microRNA-148a, and XBP1s directly bound to this response element as shown by point mutation analysis and chromatin immunoprecipitation assay. In addition, a microRNA-148a mimic significantly restored adipogenic potential in XBP1-deficient 3T3-L1 cells. These findings provide the first evidence that XBP1s can regulate Wnt10b by a post-transcriptional mechanism through directly inducing microRNA-148a.
Collapse
|
68
|
Pigment Epithelium-Derived Factor (PEDF) is a Determinant of Stem Cell Fate: Lessons from an Ultra-Rare Disease. J Dev Biol 2015; 3:112-128. [PMID: 27239449 PMCID: PMC4883593 DOI: 10.3390/jdb3040112] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
PEDF is a secreted glycoprotein that is widely expressed by multiple organs. Numerous functional contributions have been attributed to PEDF with antiangiogenic, antitumor, anti-inflammatory, and neurotrophic properties among the most prominent. The discovery that null mutations in the PEDF gene results in Osteogenesis Imperfecta Type VI, a rare autosomal recessive bone disease characterized by multiple fractures, highlights a critical developmental function for this protein. This ultra-rare orphan disease has provided biological insights into previous studies that noted PEDF’s effects on various stem cell populations. In addition to bone development, PEDF modulates resident stem cell populations in the brain, muscle, and eye. Functional effects on human embryonic stem cells have also been demonstrated. An overview of recent advances in our understanding by which PEDF regulates stem cells and their potential clinical applications will be evaluated in this review.
Collapse
|
69
|
Application of Wnt Pathway Inhibitor Delivering Scaffold for Inhibiting Fibrosis in Urethra Strictures: In Vitro and in Vivo Study. Int J Mol Sci 2015; 16:27659-76. [PMID: 26610467 PMCID: PMC4661908 DOI: 10.3390/ijms161126050] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 11/04/2015] [Accepted: 11/06/2015] [Indexed: 01/06/2023] Open
Abstract
Objective: To evaluate the mechanical property and biocompatibility of the Wnt pathway inhibitor (ICG-001) delivering collagen/poly(l-lactide-co-caprolactone) (P(LLA-CL)) scaffold for urethroplasty, and also the feasibility of inhibiting the extracellular matrix (ECM) expression in vitro and in vivo. Methods: ICG-001 (1 mg (2 mM)) was loaded into a (P(LLA-CL)) scaffold with the co-axial electrospinning technique. The characteristics of the mechanical property and drug release fashion of scaffolds were tested with a mechanical testing machine (Instron) and high-performance liquid chromatography (HPLC). Rabbit bladder epithelial cells and the dermal fibroblasts were isolated by enzymatic digestion method. (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay) and scanning electron microscopy (SEM) were used to evaluate the viability and proliferation of the cells on the scaffolds. Fibrolasts treated with TGF-β1 and ICG-001 released medium from scaffolds were used to evaluate the anti-fibrosis effect through immunofluorescence, real time PCR and western blot. Urethrography and histology were used to evaluate the efficacy of urethral implantation. Results: The scaffold delivering ICG-001 was fabricated, the fiber diameter and mechanical strength of scaffolds with inhibitor were comparable with the non-drug scaffold. The SEM and MTT assay showed no toxic effect of ICG-001 to the proliferation of epithelial cells on the collagen/P(LLA-CL) scaffold with ICG-001. After treatment with culture medium released from the drug-delivering scaffold, the expression of Collagen type 1, 3 and fibronectin of fibroblasts could be inhibited significantly at the mRNA and protein levels. In the results of urethrography, urethral strictures and fistulas were found in the rabbits treated with non-ICG-001 delivering scaffolds, but all the rabbits treated with ICG-001-delivering scaffolds showed wide caliber in urethras. Histology results showed less collagen but more smooth muscle and thicker epithelium in urethras repaired with ICG-001 delivering scaffolds. Conclusion: After loading with the Wnt signal pathway inhibitor ICG-001, the Collagen/P(LLA-CL) scaffold could facilitate a decrease in the ECM deposition of fibroblasts. The ICG-001 delivering Collagen/P(LLA-CL) nanofibrous scaffold seeded with epithelial cells has the potential to be a promising substitute material for urethroplasty. Longer follow-up study in larger animals is needed in the future.
Collapse
|
70
|
Tuo J, Wang Y, Cheng R, Li Y, Chen M, Qiu F, Qian H, Shen D, Penalva R, Xu H, Ma JX, Chan CC. Wnt signaling in age-related macular degeneration: human macular tissue and mouse model. J Transl Med 2015; 13:330. [PMID: 26476672 PMCID: PMC4609061 DOI: 10.1186/s12967-015-0683-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 09/29/2015] [Indexed: 01/02/2023] Open
Abstract
Background The wingless-type MMTV integration site (Wnt) signaling is a group of signal transduction pathways. In canonical Wnt pathway, Wnt ligands bind to low-density lipoprotein receptor-related protein 5 or 6 (LRP5 or LRP6), resulting in phosphorylation and activation of the receptor. We hypothesize that canonical Wnt pathway plays a role in the retinal lesion of age-related macular degeneration (AMD), a leading cause of irreversible central visual loss in elderly. Methods We examined LRP6 phosphorylation and Wnt signaling cascade in human retinal sections and plasma kallistatin, an endogenous inhibitor of the Wnt pathway in AMD patients and non-AMD subjects. We also used the Ccl2−/−/Cx3cr1−/−/rd8 and Ccl2−/−/Cx3cr1gfp/gfp mouse models with AMD-like retinal degeneration to further explore the involvement of Wnt signaling activation in the retinal lesions in those models and to preclinically evaluate the role of Wnt signaling suppression as a potential therapeutic option for AMD. Results We found higher levels of LRP6 (a key Wnt signaling receptor) protein phosphorylation and transcripts of the Wnt pathway-targeted genes, as well as higher beta-catenin protein in AMD macula compared to controls. Kallistatin was decreased in the plasma of AMD patients. Retinal non-phosphorylated-β-catenin and phosphorylated-LRP6 were higher in Ccl2−/−/Cx3cr1−/−/rd8 mice than that in wild type. Intravitreal administration of an anti-LRP6 antibody slowed the progression of retinal lesions in Ccl2−/−/Cx3cr1−/−/rd8 and Ccl2−/−/Cx3cr1gfp/gfp mice. Electroretinography of treated eyes exhibited larger amplitudes compared to controls in both mouse models. A2E, a retinoid byproduct associated with AMD was lower in the treated eyes of Ccl2−/−/Cx3cr1−/−/rd8 mice. Anti-LRP6 also suppressed the expression of Tnf-α and Icam-1 in Ccl2−/−/Cx3cr1−/−/rd8 retinas. Conclusions Wnt signaling may be disturbed in AMD patients, which could contribute to the retinal inflammation and increased A2E levels found in AMD. Aberrant activation of canonical Wnt signaling might also contribute to the focal retinal degenerative lesions of mouse models with Ccl2 and Cx3cr1 deficiency, and intravitreal administration of anti-LRP6 antibody could be beneficial by deactivating the canonical Wnt pathway. Electronic supplementary material The online version of this article (doi:10.1186/s12967-015-0683-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Jingsheng Tuo
- Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Drive, Bldg. 10, Rm. 10N103, NIH/NEI, Bethesda, MD, 20892-1857, USA.
| | - Yujuan Wang
- Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Drive, Bldg. 10, Rm. 10N103, NIH/NEI, Bethesda, MD, 20892-1857, USA.
| | - Rui Cheng
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
| | - Yichao Li
- Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, MD, USA.
| | - Mei Chen
- Centre for Experimental Medicine, Queen's University Belfast, Belfast, UK.
| | - Fangfang Qiu
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
| | - Haohua Qian
- Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, MD, USA.
| | - Defen Shen
- Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Drive, Bldg. 10, Rm. 10N103, NIH/NEI, Bethesda, MD, 20892-1857, USA.
| | - Rosana Penalva
- Centre for Experimental Medicine, Queen's University Belfast, Belfast, UK.
| | - Heping Xu
- Centre for Experimental Medicine, Queen's University Belfast, Belfast, UK.
| | - Jian-Xing Ma
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
| | - Chi-Chao Chan
- Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Drive, Bldg. 10, Rm. 10N103, NIH/NEI, Bethesda, MD, 20892-1857, USA.
| |
Collapse
|
71
|
Abstract
Myofibroblasts are activated in response to tissue injury with the primary task to repair lost or damaged extracellular matrix. Enhanced collagen secretion and subsequent contraction - scarring - are part of the normal wound healing response and crucial to restore tissue integrity. Due to myofibroblasts ability to repair but not regenerate, accumulation of scar tissue is always associated with reduced organ performance. This is a fair price to pay by the body for not falling apart. Whereas myofibroblasts typically vanish after successful repair, dysregulation of the normal repair process can lead to persistent myofibroblast activation, for instance by chronic inflammation or mechanical stress in the tissue. Excessive repair leads to the accumulation of stiff collagenous ECM contractures - fibrosis - with dramatic consequences for organ function. The clinical need to terminate detrimental myofibroblast activities has stimulated researchers to answer a number of essential questions: where do myofibroblasts come from, what are the factors leading to their activation, how do we discriminate myofibroblasts from other cells, what is the molecular basis for their contractile activity, and how can we stop or at least control them? This article reviews the current state of the myofibroblast literature by emphasizing their role in ocular repair and fibrosis. It appears that although the eye is quite an extraordinary organ, ocular myofibroblasts behave or misbehave just like their siblings in other organs.
Collapse
Affiliation(s)
- Boris Hinz
- Laboratory of Tissue Repair and Regeneration, Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, 150 College Street, FitzGerald Building, Room 234, Toronto, M5S 3E2 Ontario, Canada.
| |
Collapse
|
72
|
Protiva P, Gong J, Sreekumar B, Torres R, Zhang X, Belinsky GS, Cornwell M, Crawford SE, Iwakiri Y, Chung C. Pigment Epithelium-Derived Factor (PEDF) Inhibits Wnt/ β-catenin Signaling in the Liver. Cell Mol Gastroenterol Hepatol 2015; 1:535-549.e14. [PMID: 26473164 PMCID: PMC4604042 DOI: 10.1016/j.jcmgh.2015.06.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND & AIMS Pigment epithelium-derived factor (PEDF) is a secretory protein that inhibits multiple tumor types. PEDF inhibits the Wnt coreceptor, low-density lipoprotein receptor-related protein 6 (LRP6), in the eye, but whether the tumor-suppressive properties of PEDF occur in organs such as the liver is unknown. METHODS Wnt-dependent regulation of PEDF was assessed in the absence and presence of the Wnt coreceptor LRP6. Whole genome expression analysis was performed on PEDF knockout (KO) and control livers (7 months). Interrogation of Wnt/β-catenin signaling was performed in whole livers and human hepatocellular carcinoma (HCC) cell lines after RNA interference of PEDF and restoration of a PEDF-derived peptide. Western diet feeding for 6 to 8 months was used to evaluate whether the absence of PEDF was permissive for HCC formation (n = 12/group). RESULTS PEDF levels increased in response to canonical Wnt3a in an LRP6-dependent manner but were suppressed by noncanonical Wnt5a protein in an LRP6-independent manner. Gene set enrichment analysis (GSEA) of PEDF KO livers revealed induction of pathways associated with experimental and human HCC and a transcriptional profile characterized by Wnt/β-catenin activation. Enhanced Wnt/β-catenin signaling occurred in KO livers, and PEDF delivery in vivo reduced LRP6 activation. In human HCC cells, RNA interference of PEDF led to increased levels of activated LRP6 and β-catenin, and a PEDF 34-mer peptide decreased LRP6 activation and β-catenin signaling, and reduced Wnt target genes. PEDF KO mice fed a Western diet developed sporadic well-differentiated HCC. Human HCC specimens demonstrated decreased PEDF staining compared with hepatocytes. CONCLUSIONS PEDF is an endogenous inhibitor of Wnt/β-catenin signaling in the liver.
Collapse
Affiliation(s)
- Petr Protiva
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut,VA CT Healthcare System, West Haven, Connecticut
| | - Jingjing Gong
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut
| | | | - Richard Torres
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Xuchen Zhang
- VA CT Healthcare System, West Haven, Connecticut
| | - Glenn S. Belinsky
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Mona Cornwell
- Department of Pathology, St. Louis University School of Medicine, St. Louis, Missouri
| | - Susan E. Crawford
- Department of Pathology, St. Louis University School of Medicine, St. Louis, Missouri
| | - Yasuko Iwakiri
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Chuhan Chung
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut,VA CT Healthcare System, West Haven, Connecticut,Correspondence Address correspondence to: Chuhan Chung, MD, Section of Digestive Diseases, Department of Medicine, 1080 LMP, Yale University School of Medicine, New Haven, Connecticut 06519.
| |
Collapse
|
73
|
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: 102] [Impact Index Per Article: 11.3] [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
|
74
|
Gao X, Ma K, Lu N, Xu Y, Hong T, Peng X. Elevated LRP6 levels correlate with vascular endothelial growth factor in the vitreous of proliferative diabetic retinopathy. Mol Vis 2015; 21:665-72. [PMID: 26120271 PMCID: PMC4462953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 06/10/2015] [Indexed: 11/18/2022] Open
Abstract
PURPOSE To measure intravitreal low-density lipoprotein receptor-related protein 6 (LRP6) and vascular endothelial growth factor (VEGF) levels in the eyes of patients with proliferative diabetic retinopathy (PDR) and to observe their correlation with PDR activity. METHODS Fifty-five eyes of 55 patients were enrolled consecutively. Vitreous samples from 30 eyes with PDR and 25 eyes with nondiabetic macular disease were collected. Active PDR was present in 16 patients and quiescent PDR in 14 patients according to retinal neovascularization. LRP6 and VEGF concentrations in samples were determined using enzyme-linked immunosorbent assay (ELISA). RESULTS ELISA revealed significant increases in the vitreous levels of VEGF in eyes affected with PDR compared to the controls (p<0.001). The mean concentrations of LRP6 were also higher in the vitreous samples from patients with PDR compared to the nondiabetic controls: 39.85 ng/ml and 15.48 ng/ml, respectively (p=0.002). In addition, the vitreous levels of LRP6 and VEGF were significantly higher in active PDR than in quiescent PDR (p=0.022 and p=0.015, respectively). Furthermore, a significant positive correlation was found between intravitreal levels of LRP6 and VEGF in patients with PDR (r=0.567, p=0.001). However, comparison of patients with PDR with controls revealed that the plasma levels of LRP6 were not significantly different between the two groups (p=0.636). CONCLUSIONS LRP6 and VEGF levels in the vitreous body from patients with PDR were increased and correlated mutually. LRP6 may be a good diagnostic biomarker and a new therapeutic target for PDR.
Collapse
Affiliation(s)
- Xinxiao Gao
- Beijing Institute of Ophthalmology, Beijing Ophthalmology and Visual Science Key Lab, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China,Department of Ophthalmology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Kai Ma
- Department of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Ning Lu
- Department of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Yongsheng Xu
- Clinical Lab of Tissue&Cell Research Center, Department of Biotech Treatment, Logistics College of Chinese People's Armed Police Force, Tianjin, China
| | - Tingting Hong
- Department of Ophthalmology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Xiaoyan Peng
- Beijing Institute of Ophthalmology, Beijing Ophthalmology and Visual Science Key Lab, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| |
Collapse
|
75
|
Yin J, Park G, Kim TH, Hong JH, Kim YJ, Jin X, Kang S, Jung JE, Kim JY, Yun H, Lee JE, Kim M, Chung J, Kim H, Nakano I, Gwak HS, Yoo H, Yoo BC, Kim JH, Hur EM, Lee J, Lee SH, Park MJ, Park JB. Pigment Epithelium-Derived Factor (PEDF) Expression Induced by EGFRvIII Promotes Self-renewal and Tumor Progression of Glioma Stem Cells. PLoS Biol 2015; 13:e1002152. [PMID: 25992628 PMCID: PMC4439169 DOI: 10.1371/journal.pbio.1002152] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 04/10/2015] [Indexed: 12/29/2022] Open
Abstract
Epidermal growth factor receptor variant III (EGFRvIII) has been associated with glioma stemness, but the direct molecular mechanism linking the two is largely unknown. Here, we show that EGFRvIII induces the expression and secretion of pigment epithelium-derived factor (PEDF) via activation of signal transducer and activator of transcription 3 (STAT3), thereby promoting self-renewal and tumor progression of glioma stem cells (GSCs). Mechanistically, PEDF sustained GSC self-renewal by Notch1 cleavage, and the generated intracellular domain of Notch1 (NICD) induced the expression of Sox2 through interaction with its promoter region. Furthermore, a subpopulation with high levels of PEDF was capable of infiltration along corpus callosum. Inhibition of PEDF diminished GSC self-renewal and increased survival of orthotopic tumor-bearing mice. Together, these data indicate the novel role of PEDF as a key regulator of GSC and suggest clinical implications. A permanently activated mutant form of the epidermal growth factor receptor found in glioblastoma promotes self-renewal and tumor progression by inducing autocrine signalling via pigment epithelium-derived factor (PEDF). Malignant gliomas are among the most lethal types of cancer, due in part to the stem-cell-like characteristics and invasive properties of the brain tumor cells. However, little is known about the underlying molecular mechanisms that govern such processes. Here, we identify pigment epithelium-derived factor (PEDF) as a critical factor controlling stemness and tumor progression in glioma stem cells. We found that PEDF is secreted from glioblastoma expressing EGFRvIII, a frequently occurring mutation in primary glioblastoma that yields a permanently activated epidermal growth factor receptor. We delineate an EGFRvIII-STAT3-PEDF signaling axis as a signature profile of highly malignant gliomas, which promotes self-renewal of glioma stem cells. Our results demonstrate a previously unprecedented function of PEDF and implicate potential therapeutic approaches against malignant gliomas.
Collapse
Affiliation(s)
- Jinlong Yin
- Department of System Cancer Science, Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, Korea
- Specific Organs Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
| | - Gunwoo Park
- Department of System Cancer Science, Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, Korea
- Specific Organs Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
| | - Tae Hoon Kim
- Specific Organs Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
| | - Jun Hee Hong
- Specific Organs Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
| | - Youn-Jae Kim
- Specific Organs Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
| | - Xiong Jin
- Department of Biotechnology, School of Life Sciences and Biotechnology, Korea University, Seoul, Korea
| | - Sangjo Kang
- Specific Organs Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
| | - Ji-Eun Jung
- Specific Organs Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
- Department of Biotechnology, School of Life Sciences and Biotechnology, Korea University, Seoul, Korea
| | - Jeong-Yub Kim
- Divisions of Radiation Cancer Research, Research Center for Radio-Senescence, Korea Institute of Radiological and Medical Sciences, Seoul, Korea
- Department of Pathology, College of Medicine, Korea University, Seoul, Korea
| | - Hyeongsun Yun
- Department of System Cancer Science, Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, Korea
- Specific Organs Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
| | - Jeong Eun Lee
- Department of System Cancer Science, Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, Korea
- Cancer Cell and Molecular Biology Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
| | - Minkyung Kim
- Department of System Cancer Science, Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, Korea
| | - Junho Chung
- Department of Biochemistry and Molecular Biology, Seoul National University, College of Medicine, Seoul, Korea
- Department of Cancer Biology, Seoul National University College of Medicine, Seoul, Korea
| | - Hyunggee Kim
- Department of Biotechnology, School of Life Sciences and Biotechnology, Korea University, Seoul, Korea
| | - Ichiro Nakano
- Department of Neurological Surgery, The Ohio State University, Columbus, Ohio, United States of America
- James Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio, United States of America
| | - Ho-Shin Gwak
- Specific Organs Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
| | - Heon Yoo
- Department of System Cancer Science, Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, Korea
- Specific Organs Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
| | - Byong Chul Yoo
- Colorectal Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyangi, Korea
| | - Jong Heon Kim
- Department of System Cancer Science, Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, Korea
- Cancer Cell and Molecular Biology Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
| | - Eun-Mi Hur
- Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology, Seoul, Korea
- Department of Neuroscience, Korea University of Science and Technology, Daejeon, Korea
| | - Jeongwu Lee
- Department of Stem Cell Biology and Regenerative Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Seung-Hoon Lee
- Department of System Cancer Science, Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, Korea
- Specific Organs Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
- * E-mail: (SHL); (MJP); (JBP)
| | - Myung-Jin Park
- Divisions of Radiation Cancer Research, Research Center for Radio-Senescence, Korea Institute of Radiological and Medical Sciences, Seoul, Korea
- * E-mail: (SHL); (MJP); (JBP)
| | - Jong Bae Park
- Department of System Cancer Science, Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, Korea
- Specific Organs Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea
- * E-mail: (SHL); (MJP); (JBP)
| |
Collapse
|
76
|
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
|
77
|
Chetty A, Bennett M, Dang L, Nakamura D, Cao GJ, Mujahid S, Volpe M, Herman I, Becerra SP, Nielsen HC. Pigment epithelium-derived factor mediates impaired lung vascular development in neonatal hyperoxia. Am J Respir Cell Mol Biol 2015; 52:295-303. [PMID: 25054647 DOI: 10.1165/rcmb.2013-0229oc] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Bronchopulmonary dysplasia is a chronic lung disease of preterm infants characterized by arrested microvascularization and alveolarization. Studies show the importance of proangiogenic factors for alveolarization, but the importance of antiangiogenic factors is unknown. We proposed that hyperoxia increases the potent angiostatin, pigment epithelium-derived factor (PEDF), in neonatal lungs, inhibiting alveolarization and microvascularization. Wild-type (WT) and PEDF(-/-) mice were exposed to room air (RA) or 0.9 fraction of inspired oxygen from Postnatal Day 5 to 13. PEDF protein was increased in hyperoxic lungs compared with RA-exposed lungs (P < 0.05). In situ hybridization and immunofluorescence identified PEDF production primarily in alveolar epithelium. Hyperoxia reduced alveolarization in WT mice (P < 0.05) but not in PEDF(-/-) mice. WT hyperoxic mice had fewer platelet endothelial cell adhesion molecule (PECAM)-positive cells per alveolus (1.4 ± 0.4) than RA-exposed mice (4.3 ± 0.3; P < 0.05); this reduction was absent in hyperoxic PEDF(-/-) mice. The interactive regulation of lung microvascularization by vascular endothelial growth factor and PEDF was studied in vitro using MFLM-91U cells, a fetal mouse lung endothelial cell line. Vascular endothelial growth factor stimulation of proliferation, migration, and capillary tube formation was inhibited by PEDF. MFLM-91U cells exposed to conditioned medium (CM) from E17 fetal mouse lung type II (T2) cells cultured in 0.9 fraction of inspired oxygen formed fewer capillary tubes than CM from T2 cells cultured in RA (hyperoxia CM, 51 ± 10% of RA CM, P < 0.05), an effect abolished by PEDF antibody. We conclude that PEDF mediates reduced vasculogenesis and alveolarization in neonatal hyperoxia. Bronchopulmonary dysplasia likely results from an altered balance between pro- and antiangiogenic factors.
Collapse
Affiliation(s)
- Anne Chetty
- 1 Department of Pediatrics, Tufts Medical Center, Boston, Massachusetts
| | | | | | | | | | | | | | | | | | | |
Collapse
|
78
|
Qi W, Yang C, Dai Z, Che D, Feng J, Mao Y, Cheng R, Wang Z, He X, Zhou T, Gu X, Yan L, Yang X, Ma JX, Gao G. High levels of pigment epithelium-derived factor in diabetes impair wound healing through suppression of Wnt signaling. Diabetes 2015; 64:1407-19. [PMID: 25368097 DOI: 10.2337/db14-1111] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Diabetic foot ulcer (DFU) caused by impaired wound healing is a common vascular complication of diabetes. The current study revealed that plasma levels of pigment epithelium-derived factor (PEDF) were elevated in type 2 diabetic patients with DFU and in db/db mice. To test whether elevated PEDF levels contribute to skin wound-healing delay in diabetes, endogenous PEDF was neutralized with an anti-PEDF antibody in db/db mice. Our results showed that neutralization of PEDF accelerated wound healing, increased angiogenesis in the wound skin, and improved the functions and numbers of endothelial progenitor cells (EPCs) in the diabetic mice. Further, PEDF-deficient mice showed higher baseline blood flow in the skin, higher density of cutaneous microvessels, increased skin thickness, improved numbers and functions of circulating EPCs, and accelerated wound healing compared with wild-type mice. Overexpression of PEDF suppressed the Wnt signaling pathway in the wound skin. Lithium chloride-induced Wnt signaling activation downstream of the PEDF interaction site attenuated the inhibitory effect of PEDF on EPCs and rescued the wound-healing deficiency in diabetic mice. Taken together, these results suggest that elevated circulating PEDF levels contribute to impaired wound healing in the process of angiogenesis and vasculogenesis through the inhibition of Wnt/β-catenin signaling.
Collapse
Affiliation(s)
- Weiwei Qi
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, People's Republic of China Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Chuan Yang
- Department of Endocrinology, Second Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Zhiyu Dai
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Di Che
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Juan Feng
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Yuling Mao
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Rui Cheng
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Zhongxiao Wang
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Xuemin He
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Ti Zhou
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Xiaoqiong Gu
- Guangzhou Women and Children's Medical Center, Guangzhou, People's Republic of China
| | - Li Yan
- Department of Endocrinology, Second Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Xia Yang
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, People's Republic of China China Key Laboratory of Tropical Disease Control (Sun Yat-Sen University), Ministry of Education, Guangzhou, People's Republic of China
| | - Jian-Xing Ma
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Guoquan Gao
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, People's Republic of China Key Laboratory of Functional Molecules from Marine Microorganisms (Sun Yat-Sen University), Department of Education of Guangdong Province, Guangzhou, People's Republic of China
| |
Collapse
|
79
|
Abstract
The prevalence of diabetes mellitus and obesity continues to increase globally. Diabetic vascular complications are the main chronic diabetic complications and associated with mortality and disability. Angiogenesis is a key pathological characteristic of diabetic microvascular complications. However, there are two tissue-specific paradoxical changes in the angiogenesis in diabetic microvascular complications: an excessive uncontrolled formation of premature blood vessels in some tissues, such as the retina, and a deficiency in the formation of small blood vessels in peripheral tissues, such as the skin. This review will discuss the paradoxical phenomena of angiogenesis and its underlying mechanism in obesity, diabetes and diabetic complications.
Collapse
Affiliation(s)
| | - Jian-xing Ma
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| |
Collapse
|
80
|
Li F, Song N, Tombran-Tink J, Niyibizi C. Pigment Epithelium Derived Factor Suppresses Expression of Sost/Sclerostin by Osteocytes: Implication for Its Role in Bone Matrix Mineralization. J Cell Physiol 2015; 230:1243-9. [DOI: 10.1002/jcp.24859] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 10/28/2014] [Indexed: 02/06/2023]
Affiliation(s)
- Feng Li
- Department of Orthopaedics and Rehabilitation, Division of Musculoskeletal Sciences; Pennsylvania State University College of Medicine; Hershey Pennsylvania
| | - Na Song
- Department of Orthopaedics and Rehabilitation, Division of Musculoskeletal Sciences; Pennsylvania State University College of Medicine; Hershey Pennsylvania
- School of Pharmacy; Wenzhou Medical University; Wenzhou Zhejiang China
| | - Joyce Tombran-Tink
- Department of Neural and Behavioral Sciences; Pennsylvania State University College of Medicine; Hershey Pennsylvania
| | - Christopher Niyibizi
- Department of Orthopaedics and Rehabilitation, Division of Musculoskeletal Sciences; Pennsylvania State University College of Medicine; Hershey Pennsylvania
- Department of Biochemistry and Molecular Biology; Pennsylvania State University College of Medicine; Hershey Pennsylvania
| |
Collapse
|
81
|
Shin ES, Sorenson CM, Sheibani N. Diabetes and retinal vascular dysfunction. J Ophthalmic Vis Res 2015; 9:362-73. [PMID: 25667739 PMCID: PMC4307665 DOI: 10.4103/2008-322x.143378] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 01/19/2014] [Indexed: 02/06/2023] Open
Abstract
Diabetes predominantly affects the microvascular circulation of the retina resulting in a range of structural changes unique to this tissue. These changes ultimately lead to altered permeability, hyperproliferation of endothelial cells and edema, and abnormal vascularization of the retina with resulting loss of vision. Enhanced production of inflammatory mediators and oxidative stress are primary insults with significant contribution to the pathogenesis of diabetic retinopathy (DR). We have determined the identity of the retinal vascular cells affected by hyperglycemia, and have delineated the cell autonomous impact of high glucose on function of these cells. We discuss some of the high glucose specific changes in retinal vascular cells and their contribution to retinal vascular dysfunction. This knowledge provides novel insight into the molecular and cellular defects contributing to the development and progression of diabetic retinopathy, and will aid in the development of innovative, as well as target specific therapeutic approaches for prevention and treatment of DR.
Collapse
Affiliation(s)
- Eui Seok Shin
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Christine M Sorenson
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA ; McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Nader Sheibani
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA ; McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| |
Collapse
|
82
|
Carnagarin R, Dharmarajan AM, Dass CR. PEDF-induced alteration of metabolism leading to insulin resistance. Mol Cell Endocrinol 2015; 401:98-104. [PMID: 25462587 DOI: 10.1016/j.mce.2014.11.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2014] [Revised: 10/21/2014] [Accepted: 11/10/2014] [Indexed: 02/06/2023]
Abstract
Pigment epithelium-derived factor (PEDF) is an anti-angiogenic, immunomodulatory, and neurotrophic serine protease inhibitor protein. PEDF is evolving as a novel metabolic regulatory protein that plays a causal role in insulin resistance. Insulin resistance is the central pathogenesis of metabolic disorders such as obesity, type 2 diabetes mellitus, polycystic ovarian disease, and metabolic syndrome, and PEDF is associated with them. The current evidence suggests that PEDF administration to animals induces insulin resistance, whereas neutralisation improves insulin sensitivity. Inflammation, lipolytic free fatty acid mobilisation, and mitochondrial dysfunction are the proposed mechanism of PEDF-mediated insulin resistance. This review summarises the probable mechanisms adopted by PEDF to induce insulin resistance, and identifies PEDF as a potential therapeutic target in ameliorating insulin resistance.
Collapse
Affiliation(s)
- Revathy Carnagarin
- Curtin Biosciences Research Precinct, Bentley 6102, Australia; School of Pharmacy, Curtin University, Bentley 6102, Australia
| | - Arunasalam M Dharmarajan
- Curtin Biosciences Research Precinct, Bentley 6102, Australia; School of Biomedical Science, Curtin University, Bentley 6102, Australia
| | - Crispin R Dass
- Curtin Biosciences Research Precinct, Bentley 6102, Australia; School of Pharmacy, Curtin University, Bentley 6102, Australia.
| |
Collapse
|
83
|
Farnoodian M, Kinter JB, Yadranji Aghdam S, Zaitoun I, Sorenson CM, Sheibani N. Expression of pigment epithelium-derived factor and thrombospondin-1 regulate proliferation and migration of retinal pigment epithelial cells. Physiol Rep 2015; 3:3/1/e12266. [PMID: 25602019 PMCID: PMC4387751 DOI: 10.14814/phy2.12266] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Age‐related macular degeneration (AMD) is the leading cause of vision loss among elderly. Although the pathogenesis of AMD is associated with retinal pigmented epithelium (RPE) dysfunction and abnormal neovascularization the detailed mechanisms remain unresolved. RPE is a specialized monolayer of epithelial cells with important functions in ocular homeostasis. Pathological RPE damage contributes to major ocular conditions including retinal degeneration and irreversible loss of vision in AMD. RPE cells also assist in the maintenance of the ocular angiogenic balance by production of positive and negative regulatory factors including vascular endothelial growth factor (VEGF), thrombospondin‐1 (TSP1), and pigment epithelium‐derived factor (PEDF). The altered production of PEDF and TSP1, as endogenous inhibitors of angiogenesis and inflammation, by RPE cells have been linked to pathogenesis of AMD and choroidal and retinal neovascularization. However, lack of simple methods for isolation and culture of mouse RPE cells has resulted in limited knowledge regarding the cell autonomous role of TSP1 and PEDF in RPE cell function. Here, we describe a method for routine isolation and propagation of RPE cells from wild‐type, TSP1, and PEDF‐deficient mice, and have investigated their impact on RPE cell function. We showed that expression of TSP1 and PEDF significantly impacted RPE cell proliferation, migration, adhesion, oxidative state, and phagocytic activity with minimal effect on their basal rate of apoptosis. Together, our results indicated that the expression of PEDF and TSP1 by RPE cells play crucial roles not only in regulation of ocular vascular homeostasis but also have significant impact on their cellular function. Here, we report the isolation of RPE cells from wild‐type and transgenic mice retina. We demonstrate that lack of thrompospondin‐1 or pigment epithelium‐derived factor impacts the proliferation, migration, adhesion, oxidative state, and phagocytic activity of these cells.
Collapse
Affiliation(s)
- Mitra Farnoodian
- Department of Ophthalmology and Visual Sciences, Clinical Investigation Graduate Program, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin
| | - James B Kinter
- Department of Ophthalmology and Visual Sciences, Clinical Investigation Graduate Program, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin
| | - Saeed Yadranji Aghdam
- Department of Ophthalmology and Visual Sciences, Clinical Investigation Graduate Program, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin
| | - Ismail Zaitoun
- Department of Ophthalmology and Visual Sciences, Clinical Investigation Graduate Program, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin
| | - Christine M Sorenson
- Department of Pediatrics, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin McPherson Eye Research Institute, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin
| | - Nader Sheibani
- Department of Ophthalmology and Visual Sciences, Clinical Investigation Graduate Program, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin McPherson Eye Research Institute, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin Department of Biomedical Engineering, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin
| |
Collapse
|
84
|
Hong H, Zhou T, Fang S, Jia M, Xu Z, Dai Z, Li C, Li S, Li L, Zhang T, Qi W, Bardeesi ASA, Yang Z, Cai W, Yang X, Gao G. Pigment epithelium-derived factor (PEDF) inhibits breast cancer metastasis by down-regulating fibronectin. Breast Cancer Res Treat 2014; 148:61-72. [PMID: 25284724 DOI: 10.1007/s10549-014-3154-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 09/24/2014] [Indexed: 11/29/2022]
Abstract
Pigment epithelium-derived factor (PEDF) plays an important role in the tumor growth and metastasis inhibition. It has been reported that PEDF expression is significantly reduced in breast cancer, and associated with disease progression and poor patient outcome. However, the exact mechanism of PEDF on breast cancer metastasis including liver and lung metastasis remains unclear. The present study aims to reveal the impact of PEDF on breast cancer. The orthotopic tumor mice model inoculated by MDA-MB-231 cells stably expressing PEDF or control cells was used to assess liver and lung metastasis of breast cancer. In vitro, migration and invasion experiments were used to detect the metastatic abilities of MDA-MB-231 and SKBR3 breast cancer cells with or without overexpression of PEDF. The metastatic-related molecules including EMT makers, fibronectin, and p-AKT and p-ERK were detected by qRT-PCR, Western blot, and Fluorescent immunocytochemistry. PEDF significantly inhibited breast cancer growth and metastasis in vivo and in vitro. Mechanically, PEDF inhibited breast cancer cell migration and invasion by down-regulating fibronectin and subsequent MMP2/MMP9 reduction via p-ERK and p-AKT signaling pathways. However, PEDF had no effect on EMT conversion in the breast cancer cells which was usually involved in cancer metastasis. Furthermore, the study showed that laminin receptor mediated the down-regulation of fibronectin by PEDF. These results reported for the first time that PEDF inhibited breast cancer metastasis by down-regulating fibronectin via laminin receptor/AKT/ERK pathway. Our findings demonstrated PEDF as a dual effector in limiting breast cancer growth and metastasis and highlighted a new avenue to block breast cancer progression.
Collapse
Affiliation(s)
- Honghai Hong
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan Road II, Guangzhou, 510080, Guangdong, China,
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
85
|
Zhou KK, Benyajati S, Le Y, Cheng R, Zhang W, Ma JX. Interruption of Wnt signaling in Müller cells ameliorates ischemia-induced retinal neovascularization. PLoS One 2014; 9:e108454. [PMID: 25271989 PMCID: PMC4182699 DOI: 10.1371/journal.pone.0108454] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 08/29/2014] [Indexed: 01/26/2023] Open
Abstract
Retinal Müller cells are major producers of inflammatory and angiogenic cytokines which contribute to diabetic retinopathy (DR). Over-activation of the Wnt/β-catenin pathway has been shown to play an important pathogenic role in DR. However, the roles of Müller cell-derived Wnt/β-catenin signaling in retinal neovascularization (NV) and DR remain undefined. In the present study, mice with conditional β-catenin knockout (KO) in Müller cells were generated and subjected to oxygen-induced retinopathy (OIR) and streptozotocin (STZ)-induced diabetes. Wnt signaling was evaluated by measuring levels of β-catenin and expression of its target genes using immunoblotting. Retinal vascular permeability was measured using Evans blue as a tracer. Retinal NV was visualized by angiography and quantified by counting pre-retinal nuclei. Retinal pericyte loss was evaluated using retinal trypsin digestion. Electroretinography was performed to examine visual function. No abnormalities were detected in the β-catenin KO mice under normal conditions. In OIR, retinal levels of β-catenin and VEGF were significantly lower in the β-catenin KO mice than in littermate controls. The KO mice also had decreased retinal NV and vascular leakage in the OIR model. In the STZ-induced diabetic model, disruption of β-catenin in Müller cells attenuated over-expression of inflammatory cytokines and ameliorated pericyte dropout in the retina. These findings suggest that Wnt signaling activation in Müller cells contributes to retinal NV, vascular leakage and inflammation and represents a potential therapeutic target for DR.
Collapse
Affiliation(s)
- Kelu Kevin Zhou
- Department of Physiology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Siribhinya Benyajati
- Department of Physiology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Yun Le
- Department of Medicine Endocrinology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Rui Cheng
- Department of Physiology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Wenbo Zhang
- Department of Ophthalmology and Visual Sciences, the University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Jian-xing Ma
- Department of Physiology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
- * E-mail:
| |
Collapse
|
86
|
Molecular mechanisms of diabetic retinopathy, general preventive strategies, and novel therapeutic targets. BIOMED RESEARCH INTERNATIONAL 2014; 2014:801269. [PMID: 25105142 PMCID: PMC4106080 DOI: 10.1155/2014/801269] [Citation(s) in RCA: 137] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 05/04/2014] [Accepted: 05/24/2014] [Indexed: 01/09/2023]
Abstract
The growing number of people with diabetes worldwide suggests that diabetic retinopathy (DR) and diabetic macular edema (DME) will continue to be sight threatening factors. The pathogenesis of diabetic retinopathy is a widespread cause of visual impairment in the world and a range of hyperglycemia-linked pathways have been implicated in the initiation and progression of this condition. Despite understanding the polyol pathway flux, activation of protein kinase C (KPC) isoforms, increased hexosamine pathway flux, and increased advanced glycation end-product (AGE) formation, pathogenic mechanisms underlying diabetes induced vision loss are not fully understood. The purpose of this paper is to review molecular mechanisms that regulate cell survival and apoptosis of retinal cells and discuss new and exciting therapeutic targets with comparison to the old and inefficient preventive strategies. This review highlights the recent advancements in understanding hyperglycemia-induced biochemical and molecular alterations, systemic metabolic factors, and aberrant activation of signaling cascades that ultimately lead to activation of a number of transcription factors causing functional and structural damage to retinal cells. It also reviews the established interventions and emerging molecular targets to avert diabetic retinopathy and its associated risk factors.
Collapse
|
87
|
Askou AL. Development of gene therapy for treatment of age-related macular degeneration. Acta Ophthalmol 2014; 92 Thesis3:1-38. [PMID: 24953666 DOI: 10.1111/aos.12452] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Intraocular neovascular diseases are the leading cause of blindness in the Western world in individuals over the age of 50. Age-related macular degeneration (AMD) is one of these diseases. Exudative AMD, the late-stage form, is characterized by abnormal neovessel development, sprouting from the choroid into the avascular subretinal space, where it can suddenly cause irreversible damage to the vulnerable photoreceptor (PR) cells essential for our high-resolution, central vision. The molecular basis of AMD is not well understood, but several growth factors have been implicated including vascular endothelial growth factor (VEGF), and the advent of anti-VEGF therapy has markedly changed the outcome of treatment. However, common to all current therapies for exudative AMD are the complications of repeated monthly intravitreal injections, which must be continued throughout one's lifetime to maintain visual benefits. Additionally, some patients do not benefit from established treatments. Strategies providing long-term suppression of inappropriate ocular angiogenesis are therefore needed, and gene therapy offers a potential powerful technique. This study aimed to develop a strategy based on RNA interference (RNAi) for the sustained attenuation of VEGF. We designed a panel of anti-VEGF short hairpin RNAs (shRNA), and based on the most potent shRNAs, microRNA (miRNA)-mimicked hairpins were developed. We demonstrated an additive VEGF silencing effect when we combined the miRNAs in a tricistronic miRNA cluster. To meet the requirements for development of medical treatments for AMD with long-term effects, the shRNA/miRNA is expressed from vectors based on adeno-associated virus (AAV) or lentivirus (LV). Both vector systems have been found superior in terms of transduction efficiency and persistence in gene expression in retinal cells. The capacity of AAV-encoded RNAi effector molecules to silence endogenous VEGF gene expression was evaluated in mouse models, including the model of laser-induced choroidal neovascularization (CNV), and we found that subretinal administration of self-complementary (sc)-AAV2/8 encoding anti-VEGF shRNAs can impair vessel formation. In parallel, a significant reduction of endogenous VEGF was demonstrated following injection of scAAV2/8 vectors expressing multiple anti-VEGF miRNAs into murine hind limb muscles. Furthermore, in an ongoing project we have designed versatile, multigenic LV vectors with combined expression of multiple miRNAs and proteins, including pigment epithelium-derived factor (PEDF), a multifunctional, secreted protein that has anti-angiogenic and neurotrophic functions. Co-expression of miRNAs and proteins from a single viral vector increases safety by minimizing the viral load necessary to obtain a therapeutic effect and thereby reduces the risk of insertional mutagenesis as well as the immune response against viral proteins. Our results show co-expression of functional anti-VEGF-miRNAs and PEDF in cell studies, and in vivo studies reveal an efficient retinal pigment epithelium (RPE)-specific gene expression following the incorporation of the vitelliform macular dystrophy 2 (VMD2) promoter, demonstrating the potential applicability of our multigenic LV vectors in ocular anti-VEGF gene therapy, including combination therapy for treatment of exudative AMD. In conclusion, these highly promising data clearly demonstrate that viral-encoded RNAi effector molecules can be used for the inhibition of neovascularization and will, in combination with the growing interest of applying DNA- or RNA-based technologies in the clinic, undoubtedly contribute to the development of efficacious long-term gene therapy treatment of intraocular neovascular diseases.
Collapse
|
88
|
Murphy-Ullrich JE, Sage EH. Revisiting the matricellular concept. Matrix Biol 2014; 37:1-14. [PMID: 25064829 PMCID: PMC4379989 DOI: 10.1016/j.matbio.2014.07.005] [Citation(s) in RCA: 286] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 07/07/2014] [Accepted: 07/08/2014] [Indexed: 12/16/2022]
Abstract
The concept of a matricellular protein was first proposed by Paul Bornstein in the mid-1990s to account for the non-lethal phenotypes of mice with inactivated genes encoding thrombospondin-1, tenascin-C, or SPARC. It was also recognized that these extracellular matrix proteins were primarily counter or de-adhesive. This review reappraises the matricellular concept after nearly two decades of continuous investigation. The expanded matricellular family as well as the diverse and often unexpected functions, cellular location, and interacting partners/receptors of matricellular proteins are considered. Development of therapeutic strategies that target matricellular proteins are discussed in the context of pathology and regenerative medicine.
Collapse
Affiliation(s)
- Joanne E Murphy-Ullrich
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294-0019, United States.
| | | |
Collapse
|
89
|
Tsai TH, Shih SC, Ho TC, Ma HI, Liu MY, Chen SL, Tsao YP. Pigment epithelium-derived factor 34-mer peptide prevents liver fibrosis and hepatic stellate cell activation through down-regulation of the PDGF receptor. PLoS One 2014; 9:e95443. [PMID: 24763086 PMCID: PMC3998957 DOI: 10.1371/journal.pone.0095443] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 03/27/2014] [Indexed: 01/28/2023] Open
Abstract
Pigment epithelium-derived factor (PEDF) has been shown previously to prevent liver fibrosis and hepatic stellate cell (HSC) activation. By investigating the functional domains in PEDF, we identified a 34-mer peptide (residues Asp44-Asn77) that harbors the same function as the full-length PEDF protein. Not only did the 34-mer suppress the development of fibrosis in carbon tetrachloride (CCl4)-treated mouse liver but it also upregulated peroxisome proliferator-activated receptor-gamma (PPARγ) expression in HSCs in vivo. Platelet-derived growth factor (PDGF) plays a crucial role on the process of HSC activation in response to liver damage. The 34-mer suppressed PDGF-induced cell proliferation and expression of myofibroblastic marker proteins in primary rat HSC culture, increased the levels of PPARγ mRNA and protein in a dose-dependent manner and markedly reduced the level of active β-catenin protein, an HSC activating factor, in HSC-T6 cells. Similarly, IWR-1, an inhibitor of the Wnt response, displayed the same effect as the 34-mer in preventing HSC-T6 activation. The Wnt signaling-mediated PPARγ suppression was abolished by both the IWR-1 inhibitor and a small interfering RNA (siRNA) targeting β-catenin and the Wnt coreceptor, LRP6. Both PEDF and the 34-mer down-regulated PDGF receptor-α/β expression and blocked the PDGF-induced phosphorylation of Akt and ERK. Moreover, the inhibitory effect on PDGF receptor expression was abolished by PPARγ antagonists and PPARγ siRNA. Our observations indicate that the PEDF-derived 34-mer peptide can mimic PEDF in attenuating HSC activation. Investigation of this 34-mer peptide led to the identification of a signaling mechanism involving PPARγ induction, suppression of Wnt/β-catenin signaling and down-regulation of the PDGF receptor-α/β.
Collapse
Affiliation(s)
- Tung-Han Tsai
- Department of Neurosurgery, Tri-Service General Hospital, National Defense Center, Taipei, Republic of China
| | - Shou-Chuan Shih
- Department of Gastroenterology, Mackay Memorial Hospital, Taipai, Republic of China
- Mackay Medicine, Nursing and Management College, Taipei, Republic of China
| | - Tsung-Chuan Ho
- Department of Medical Research, Mackay Memorial Hospital, Taipei, Republic of China
| | - Hsin-I Ma
- Department of Neurosurgery, Tri-Service General Hospital, National Defense Center, Taipei, Republic of China
| | - Ming-Ying Liu
- Department of Neurosurgery, Tri-Service General Hospital, National Defense Center, Taipei, Republic of China
| | - Show-Li Chen
- Department of Microbiology, School of Medicine, National Taiwan University, Taipei, Republic of China
| | - Yeou-Ping Tsao
- Department of Medical Research, Mackay Memorial Hospital, Taipei, Republic of China
- * E-mail:
| |
Collapse
|
90
|
Gattu AK, Birkenfeld AL, Iwakiri Y, Jay S, Saltzman M, Doll J, Protiva P, Samuel VT, Crawford SE, Chung C. Pigment epithelium-derived factor (PEDF) suppresses IL-1β-mediated c-Jun N-terminal kinase (JNK) activation to improve hepatocyte insulin signaling. Endocrinology 2014; 155:1373-85. [PMID: 24456163 PMCID: PMC5393334 DOI: 10.1210/en.2013-1785] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Pigment epithelium-derived factor (PEDF) is an antiinflammatory protein that circulates at high levels in the metabolic syndrome. Metabolic studies of PEDF knockout (KO) mice were conducted to investigate the relationship between PEDF, inflammatory markers, and metabolic homeostasis. Male PEDF KO mice demonstrated a phenotype consisting of increased adiposity, glucose intolerance, and elevated serum levels of metabolites associated with the metabolic syndrome. Genome expression analysis revealed an increase in IL-1β signaling in the livers of PEDF KO mice that was accompanied by impaired IRS and Akt signaling. In human hepatocytes, PEDF blocked the effects of an IL-1β challenge by suppressing activation of the inflammatory mediator c-Jun N-terminal kinase while restoring Akt signaling. RNA interference of PEDF in human hepatocytes was permissive for c-Jun N-terminal kinase activation and decreased Akt signaling. A metabolomics profile identified elevated circulating levels of tricarboxyclic acid cycle intermediates including succinate, an inducer of IL-1β, in PEDF KO mice. Succinate-dependent IL-1β expression was blocked by PEDF in PEDF KO, but not wild-type hepatocytes. In vivo, PEDF restoration reduced hyperglycemia and improved hepatic insulin signaling in PEDF KO mice. These findings identify elevated PEDF as a homeostatic mechanism in the human metabolic syndrome.
Collapse
Affiliation(s)
- Arijeet K Gattu
- Sections of Digestive Diseases (A.K.G., Y.I., P.P., C.C.); Endocrinology, Department of Medicine (A.L.B., V.T.S.), Yale University School of Medicine, New Haven, Connecticut 06520; Veterans Affairs Connecticut Healthcare System (P.P., V.T.S., C.C.), West Haven, Connecticut 06516; Department of Biomedical Engineering (S.J., M.S.), Yale University, New Haven, Connecticut 06511; Department of Pathology (S.E.C.), St Louis University School of Medicine, St Louis, Missouri 63104; and Department of Biomedical Sciences (J.D.), University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201
| | | | | | | | | | | | | | | | | | | |
Collapse
|
91
|
Shin ES, Sorenson CM, Sheibani N. PEDF expression regulates the proangiogenic and proinflammatory phenotype of the lung endothelium. Am J Physiol Lung Cell Mol Physiol 2013; 306:L620-34. [PMID: 24318110 DOI: 10.1152/ajplung.00188.2013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Pigment epithelium-derived factor (PEDF) is a multifunctional protein with important roles in regulation of inflammation and angiogenesis. It is produced by various cell types, including endothelial cells (EC). However, the cell autonomous impact of PEDF on EC function needs further investigation. Lung EC prepared from PEDF-deficient (PEDF-/-) mice were more migratory and failed to undergo capillary morphogenesis in Matrigel compared with wild type (PEDF+/+) EC. Although no significant differences were observed in the rates of apoptosis in PEDF-/- EC compared with PEDF+/+ cells under basal or stress conditions, PEDF-/- EC proliferated at a slower rate. PEDF-/- EC also expressed increased levels of proinflammatory markers, including vascular endothelial growth factor, inducible nitric oxide synthase, vascular cell adhesion molecule-1, as well as altered cellular junctional organization, and nuclear localization of β-catenin. The PEDF-/- EC were also more adhesive, expressed decreased levels of thrombospondin-2, tenascin-C, and osteopontin, and increased fibronectin. Furthermore, we showed lungs from PEDF-/- mice exhibited increased expression of macrophage marker F4/80, along with increased thickness of the vascular walls, consistent with a proinflammatory phenotype. Together, our data suggest that the PEDF expression makes significant contribution to modulation of the inflammatory and angiogenic phenotype of the lung endothelium.
Collapse
Affiliation(s)
- Eui Seok Shin
- Dept. of Ophthalmology and Visual Sciences, Univ. of Wisconsin, 600 Highland Ave., K6/458 CSC, Madison, WI 53792-4673.
| | | | | |
Collapse
|
92
|
Liu X, Zhang B, McBride JD, Zhou K, Lee K, Zhou Y, Liu Z, Ma JX. Antiangiogenic and antineuroinflammatory effects of kallistatin through interactions with the canonical Wnt pathway. Diabetes 2013; 62:4228-38. [PMID: 23884893 PMCID: PMC3837048 DOI: 10.2337/db12-1710] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Kallistatin is a member of the serine proteinase inhibitor superfamily. Kallistatin levels have been shown to be decreased in the vitreous while increased in the circulation of patients with diabetic retinopathy (DR). Overactivation of the Wnt pathway is known to play pathogenic roles in DR. To investigate the role of kallistatin in DR and in Wnt pathway activation, we generated kallistatin transgenic (kallistatin-TG) mice overexpressing kallistatin in multiple tissues including the retina. In the oxygen-induced retinopathy (OIR) model, kallistatin overexpression attenuated ischemia-induced retinal neovascularization. In diabetic kallistatin-TG mice, kallistatin overexpression ameliorated retinal vascular leakage, leukostasis, and overexpression of vascular endothelial growth factor and intracellular adhesion molecule. Furthermore, kallistatin overexpression also suppressed Wnt pathway activation in the retinas of the OIR and diabetic models. In diabetic Wnt reporter (BAT-gal) mice, kallistatin overexpression suppressed retinal Wnt reporter activity. In cultured retinal cells, kallistatin blocked Wnt pathway activation induced by high glucose and by Wnt ligand. Coprecipitation and ligand-binding assays both showed that kallistatin binds to a Wnt coreceptor LRP6 with high affinity (Kd = 4.5 nmol/L). These observations suggest that kallistatin is an endogenous antagonist of LRP6 and inhibitor of Wnt signaling. The blockade of Wnt signaling may represent a mechanism for its antiangiogenic and antineuroinflammatory effects.
Collapse
Affiliation(s)
- Xiaochen Liu
- Eye Institute of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, China
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Bin Zhang
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas
| | - Jeffrey D. McBride
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Kevin Zhou
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Kyungwon Lee
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Yueping Zhou
- Eye Institute of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, China
| | - Zuguo Liu
- Eye Institute of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, China
- Corresponding authors: Zuguo Liu, , and Jian-xing Ma,
| | - Jian-xing Ma
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
- Corresponding authors: Zuguo Liu, , and Jian-xing Ma,
| |
Collapse
|
93
|
Affiliation(s)
- Ling Zhao
- Molecular Medicine Research Center, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Ophthalmology and Shiley Eye Center, and Institute for Genomic Medicine, University of California, San Diego, La Jolla, California
| | - Sherrina H. Patel
- Department of Ophthalmology and Shiley Eye Center, and Institute for Genomic Medicine, University of California, San Diego, La Jolla, California
| | - Jacqueline Pei
- Molecular Medicine Research Center, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Ophthalmology and Shiley Eye Center, and Institute for Genomic Medicine, University of California, San Diego, La Jolla, California
| | - Kang Zhang
- Molecular Medicine Research Center, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Ophthalmology and Shiley Eye Center, and Institute for Genomic Medicine, University of California, San Diego, La Jolla, California
- Veterans Administration Healthcare System, San Diego, California
- Corresponding author: Kang Zhang,
| |
Collapse
|
94
|
Gattu AK, Swenson ES, Iwakiri Y, Samuel VT, Troiano N, Berry R, Church CD, Rodeheffer MS, Carpenter TO, Chung C. Determination of mesenchymal stem cell fate by pigment epithelium-derived factor (PEDF) results in increased adiposity and reduced bone mineral content. FASEB J 2013; 27:4384-94. [PMID: 23887690 DOI: 10.1096/fj.13-232900] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Pigment epithelium-derived factor (PEDF), the protein product of the SERPINF1 gene, has been linked to distinct diseases involving adipose or bone tissue, the metabolic syndrome, and osteogenesis imperfecta (OI) type VI. Since mesenchymal stem cell (MSC) differentiation into adipocytes vs. osteoblasts can be regulated by specific factors, PEDF-directed dependency of murine and human MSCs was assessed. PEDF inhibited adipogenesis and promoted osteoblast differentiation of murine MSCs, osteoblast precursors, and human MSCs. Blockade of adipogenesis by PEDF suppressed peroxisome proliferator-activated receptor-γ (PPARγ), adiponectin, and other adipocyte markers by nearly 90% compared with control-treated cells (P<0.001). Differentiation to osteoblasts by PEDF resulted in a common pathway that involved PPARγ suppression (P<0.01). Canonical Wnt-β-catenin signaling results in a MSC differentiation pattern analogous to that seen with PEDF. Thus, adding PEDF enhanced Wnt-β-catenin signal transduction in human MSCs, demonstrating a novel Wnt agonist function. In PEDF knockout (KO) mice, total body adiposity was increased by >50% compared with controls, illustrating its systemic role as a negative regulator of adipogenesis. Bones from KO mice demonstrated a reduction in mineral content recapitulating the OI type VI phenotype. These results demonstrate that the human diseases associated with PEDF reflect its ability to modulate MSC differentiation.
Collapse
Affiliation(s)
- Arijeet K Gattu
- 1Section of Digestive Diseases, Department of Medicine, Yale University School of Medicine, 1080 LMP, New Haven, CT, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
95
|
Klinger P, Beyer C, Ekici AB, Carl HD, Schett G, Swoboda B, Hennig FF, Gelse K. The Transient Chondrocyte Phenotype in Human Osteophytic Cartilage: A Role of Pigment Epithelium-Derived Factor? Cartilage 2013; 4:249-55. [PMID: 26069671 PMCID: PMC4297088 DOI: 10.1177/1947603513480809] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To identify factors that are responsible for the phenotypic differences between transient chondrocytes within human osteophytes prone to endochondral ossification and permanent chondrocytes within articular cartilage persisting for decades. METHODS Differential gene expression of chondrocytes from human osteophytes or from articular cartilage was detected by cDNA microarray analysis. The expression of pigment epithelium-derived factor (PEDF), one of the most impressively differentially expressed genes, was validated by quantitative reverse transcriptase polymerase chain reaction as well as immunohistochemistry. The mode of action of PEDF was explored by cell viability assays and by detecting target genes. RESULTS PEDF mRNA expression was upregulated by 118.5-fold (P = 0.01) in human osteophytic cartilage compared with articular cartilage, which was reflected by strong immunostaining for PEDF in the cartilaginous layer of osteophytes but largely negative staining in articular cartilage. Elevated levels of PEDF in osteophytes were associated with enhanced apoptosis. PEDF increased the expression of the proapoptotic factor FasL and induced cell death in cell culture. Osteochondral progenitor cells were more responsive to PEDF than differentiated articular chondrocytes. CONCLUSIONS The induction of the proapoptotic factor PEDF within the osteophyte cartilage suggests a molecular concept for the transient chondrocyte phenotype that arises from progenitor cells and is prone to terminal differentiation and cell death.
Collapse
Affiliation(s)
- Patricia Klinger
- Department of Orthopaedic Trauma Surgery, University Hospital Erlangen, Erlangen, Germany,Department of Orthopaedic Rheumatology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Christian Beyer
- Department of Internal Medicine III and Institute for Clinical Immunology, University Erlangen-Nuremberg, Erlangen, Germany
| | - Arif B. Ekici
- Institute of Human Genetics, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Hans-Dieter Carl
- Department of Orthopaedic Rheumatology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Georg Schett
- Department of Internal Medicine III and Institute for Clinical Immunology, University Erlangen-Nuremberg, Erlangen, Germany
| | - Bernd Swoboda
- Department of Orthopaedic Rheumatology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Friedrich F. Hennig
- Department of Orthopaedic Trauma Surgery, University Hospital Erlangen, Erlangen, Germany
| | - Kolja Gelse
- Department of Orthopaedic Trauma Surgery, University Hospital Erlangen, Erlangen, Germany
| |
Collapse
|
96
|
Subramanian P, Locatelli-Hoops S, Kenealey J, DesJardin J, Notari L, Becerra SP. Pigment epithelium-derived factor (PEDF) prevents retinal cell death via PEDF Receptor (PEDF-R): identification of a functional ligand binding site. J Biol Chem 2013; 288:23928-42. [PMID: 23818523 DOI: 10.1074/jbc.m113.487884] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The extracellular pigment epithelium-derived factor (PEDF) displays retina survival activity by interacting with receptor proteins on cell surfaces. We have previously reported that PEDF binds and stimulates PEDF receptor (PEDF-R), a transmembrane phospholipase. However, the PEDF binding site of PEDF-R and its involvement in survival activity have not been identified. The purpose of this work is to identify a biologically relevant ligand-binding site on PEDF-R. PEDF bound the PEDF-R ectodomain L4 (Leu(159)-Met(325)) with affinity similar to the full-length PEDF-R (Met(1)-Leu(504)). Binding assays using synthetic peptides spanning L4 showed that PEDF selectively bound E5b (Ile(193)-Leu(232)) and P1 (Thr(210)-Leu(249)) peptides. Recombinant C-terminal truncated PEDF-R4 (Met(1)-Leu(232)) and internally truncated PEDF-R and PEDF-R4 (ΔHis(203)-Leu(232)) retained phospholipase activity of the full-length PEDF-R. However, PEDF-R polypeptides without the His(203)-Leu(232) region lost the PEDF affinity that stimulated their enzymatic activity. Cell surface labeling showed that PEDF-R is present in the plasma membranes of retina cells. Using siRNA to selectively knock down PEDF-R in retina cells, we demonstrated that PEDF-R is essential for PEDF-mediated cell survival and antiapoptotic activities. Furthermore, preincubation of PEDF with P1 and E5b peptides blocked the PEDF·PEDF-R-mediated retina cell survival activity, implying that peptide binding to PEDF excluded ligand-receptor interactions on the cell surface. Our findings establish that PEDF-R is required for the survival and antiapoptotic effects of PEDF on retina cells and has determinants for PEDF binding within its L4 ectodomain that are critical for enzymatic stimulation.
Collapse
Affiliation(s)
- Preeti Subramanian
- Section of Protein Structure and Function, Laboratory of Retinal Cell and Molecular Biology, NEI, National Institutes of Health, Bethesda, Maryland 20892, USA
| | | | | | | | | | | |
Collapse
|
97
|
Affiliation(s)
- Francis H Glorieux
- Shriners Hospital for Children and McGill University, Montreal, QC, Canada
| | | |
Collapse
|
98
|
Titchenell PM, Antonetti DA. Using the past to inform the future: anti-VEGF therapy as a road map to develop novel therapies for diabetic retinopathy. Diabetes 2013; 62:1808-15. [PMID: 23704522 PMCID: PMC3661651 DOI: 10.2337/db12-1744] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Therapies targeting vascular endothelial growth factor (VEGF) are revolutionizing the treatment of diabetic retinopathy (DR) and diabetic macular edema (DME). In August 2012, ranibizumab, a monoclonal antibody fragment targeting VEGF designed for ocular use, became the first and only U.S. Food and Drug Administration-approved medical therapy for DME and the first approved treatment in over 25 years. This approval was based on strong preclinical data followed by numerous clinical trials that demonstrate an essential role of VEGF in vascular permeability and angiogenesis in both normal physiology and disease pathology. In this Perspective, we will examine the experimental studies and scientific data that aided in the success of the development of therapies targeting VEGF and consider how these approaches may inform the development of future therapeutics for diabetic eye disease. A multipoint model is proposed, based on well-established drug development principles, with the goal of improving the success of clinical drug development. This model suggests that to provide a validated preclinical target, investigators should demonstrate the following: the role of the target in normal physiology, a causal link to disease pathogenesis, correlation to human disease, and the ability to elicit clinically relevant improvements of disease phenotypes in animal models with multiple, chemically diverse interventions. This model will provide a framework to validate the current preclinical targets and identify novel targets to improve drug development success for DR.
Collapse
Affiliation(s)
- Paul M. Titchenell
- Department of Cellular and Molecular Physiology, Penn State University College of Medicine, Hershey, Pennsylvania
| | - David A. Antonetti
- Departments of Ophthalmology and Visual Sciences and Molecular and Integrative Physiology, The University of Michigan, Ann Arbor, Michigan
- Corresponding author: David A. Antonetti,
| |
Collapse
|
99
|
Zhang F, Dai M, Neng L, Zhang JH, Zhi Z, Fridberger A, Shi X. Perivascular macrophage-like melanocyte responsiveness to acoustic trauma--a salient feature of strial barrier associated hearing loss. FASEB J 2013; 27:3730-40. [PMID: 23729595 DOI: 10.1096/fj.13-232892] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Tissue perivascular resident macrophages (PVM/Ms), a hybrid cell type with characteristics of both macrophages and melanocytes, are critical for establishing and maintaining the endocochlear potential (EP) required for hearing. The PVM/Ms modulate expression of tight- and adherens-junction proteins in the endothelial barrier of the stria vascularis (intrastrial fluid-blood barrier) through secretion of a signaling molecule, pigment epithelium growth factor (PEDF). Here, we identify a significant link between abnormalities in PVM/Ms and endothelial barrier breakdown from acoustic trauma to the mouse ear. We find that acoustic trauma causes activation of PVM/Ms and physical detachment from capillary walls. Concurrent with the detachment, we find loosened tight junctions between endothelial cells and decreased production of tight- and adherens-junction protein, resulting in leakage of serum proteins from the damaged barrier. A key factor in the intrastrial fluid-blood barrier hyperpermeability exhibited in the mice is down-regulation of PVM/M modulated PEDF production. We demonstrate that delivery of PEDF to the damaged ear ameliorates hearing loss by restoring intrastrial fluid-blood barrier integrity. PEDF up-regulates expression of tight junction-associated proteins (ZO-1 and VE-cadherin) and PVM/M stabilizing neural cell adhesion molecule (NCAM-120). These studies point to the critical role PVM/Ms play in regulating intrastrial fluid-blood barrier integrity in healthy and noise-damaged ears.
Collapse
Affiliation(s)
- Fei Zhang
- Oregon Hearing Research Center, Department of Otolaryngology/Head and Neck Surgery, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd., Portland, OR 97239-3098, USA
| | | | | | | | | | | | | |
Collapse
|
100
|
Craword SE, Fitchev P, Veliceasa D, Volpert OV. The many facets of PEDF in drug discovery and disease: a diamond in the rough or split personality disorder? Expert Opin Drug Discov 2013; 8:769-92. [PMID: 23642051 DOI: 10.1517/17460441.2013.794781] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Pigment epithelium-derived factor (PEDF) was discovered as a neurotrophic factor secreted by retinal pigment epithelial cells. A decade later, it re-emerged as a powerful angiogenesis inhibitor guarding ocular function. Since then, significant advances were made identifying PEDF's mechanisms, targets and biomedical applications. AREAS COVERED The authors review several methodologies that have generated significant new information about the potential of PEDF as a drug. Furthermore, the authors review and discuss mechanistic and structure-function analyses combined with the functional mapping of active fragments, which have yielded several short bioactive PEDF peptides. Additionally, the authors present functional studies in knockout animals and human correlates that have provided important information about conditions amenable to PEDF-based therapies. EXPERT OPINION Through its four known receptors, PEDF causes a wide range of cellular events vitally important for the organism, which include survival and differentiation, migration and invasion, lipid metabolism and stem cell maintenance. These processes are deregulated in multiple pathological conditions, including cancer, metabolic and cardiovascular disease. PEDF has been successfully used in countless preclinical models of these conditions and human correlates suggest a wide utility of PEDF-based drugs. The most significant clinical application of PEDF, to date, is its potential therapeutic use for age-related macular degeneration. Moreover, PEDF-based gene therapy has advanced to early stage clinical trials. PEDF active fragments have been mapped and used to design short peptide mimetics conferring distinct functions of PEDF, which may address specific clinical problems and become prototype drugs.
Collapse
Affiliation(s)
- Susan E Craword
- St. Louis University School of Medicine, Department of Pathology, St. Louis, Missouri, USA
| | | | | | | |
Collapse
|