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The Role of Connexin in Ophthalmic Neovascularization and the Interaction between Connexin and Proangiogenic Factors. J Ophthalmol 2022; 2022:8105229. [PMID: 35783340 PMCID: PMC9242797 DOI: 10.1155/2022/8105229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 06/11/2022] [Indexed: 12/02/2022] Open
Abstract
The formation of new blood vessels is an important physiological process that occurs during development. When the body is injured, new blood vessel formation helps the body recuperate by supplying more oxygen and nutrients. However, this mechanism can have a negative effect. In ophthalmologic diseases, such as corneal new blood vessels, neonatal vascular glaucoma, and diabetes retinopathy, the formation of new blood vessels has become a critical component in patient survival. Connexin is a protein that regulates the cellular and molecular material carried by cells. It has been demonstrated that it is widely expressed in vascular endothelial cells, where it forms a slit connection between adjacent cells to promote cell-cell communication via hemichannels, as well as substance exchange into intracellular environments. Numerous studies have demonstrated that connexin in vascular endothelial cells plays an important role in angiogenesis and vascular leakage. The purpose of this study was to investigate the effect between the angiogenesis-associated factor and the connexin. It also reveals the effect of connexin on ophthalmic neovascularization.
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Gehmeyr J, Maghnouj A, Tjaden J, Vorgerd M, Hahn S, Matschke V, Theis V, Theiss C. Disabling VEGF-Response of Purkinje Cells by Downregulation of KDR via miRNA-204-5p. Int J Mol Sci 2021; 22:2173. [PMID: 33671638 PMCID: PMC7926311 DOI: 10.3390/ijms22042173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 02/12/2021] [Accepted: 02/19/2021] [Indexed: 12/16/2022] Open
Abstract
The vascular endothelial growth factor (VEGF) is well known for its wide-ranging functions, not only in the vascular system, but also in the central (CNS) and peripheral nervous system (PNS). To study the role of VEGF in neuronal protection, growth and maturation processes have recently attracted much interest. These effects are mainly mediated by VEGF receptor 2 (VEGFR-2). Current studies have shown the age-dependent expression of VEGFR-2 in Purkinje cells (PC), promoting dendritogenesis in neonatal, but not in mature stages. We hypothesize that microRNAs (miRNA/miR) might be involved in the regulation of VEGFR-2 expression during the development of PC. In preliminary studies, we performed a miRNA profiling and identified miR204-5p as a potential regulator of VEGFR-2 expression. In the recent study, organotypic slice cultures of rat cerebella (postnatal day (p) 1 and 9) were cultivated and VEGFR-2 expression in PC was verified via immunohistochemistry. Additionally, PC at age p9 and p30 were isolated from cryosections by laser microdissection (LMD) to analyse VEGFR-2 expression by quantitative RT-PCR. To investigate the influence of miR204-5p on VEGFR-2 levels in PC, synthetic constructs including short hairpin (sh)-miR204-5p cassettes (miRNA-mimics), were microinjected into PC. The effects were analysed by confocal laser scanning microscopy (CLSM) and morphometric analysis. For the first time, we could show that miR204-5p has a negative effect on VEGF sensitivity in juvenile PC, resulting in a significant decrease of dendritic growth compared to untreated juvenile PC. In mature PC, the overexpression of miR204-5p leads to a shrinkage of dendrites despite VEGF treatment. The results of this study illustrate, for the first time, which miR204-5p expression has the potential to play a key role in cerebellar development by inhibiting VEGFR-2 expression in PC.
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Affiliation(s)
- Julian Gehmeyr
- Department of Cytology, Institute of Anatomy, Ruhr-University Bochum, Universitaetsstr. 150, Building MA, Level 5, 44780 Bochum, Germany; (J.G.); (J.T.); (V.M.); (V.T.)
| | - Abdelouahid Maghnouj
- Clinical Research Centre (ZKF), Department of Molecular Gastrointestinal Oncology, Ruhr-University Bochum, Universitaetsstr. 150, 44801 Bochum, Germany; (A.M.); (S.H.)
| | - Jonas Tjaden
- Department of Cytology, Institute of Anatomy, Ruhr-University Bochum, Universitaetsstr. 150, Building MA, Level 5, 44780 Bochum, Germany; (J.G.); (J.T.); (V.M.); (V.T.)
| | - Matthias Vorgerd
- Neuromuscular Center Ruhrgebiet, Department of Neurology, University Hospital Bergmannsheil, Ruhr-University Bochum, Buerkle-de-la-Camp-Platz 1, 44789 Bochum, Germany;
| | - Stephan Hahn
- Clinical Research Centre (ZKF), Department of Molecular Gastrointestinal Oncology, Ruhr-University Bochum, Universitaetsstr. 150, 44801 Bochum, Germany; (A.M.); (S.H.)
| | - Veronika Matschke
- Department of Cytology, Institute of Anatomy, Ruhr-University Bochum, Universitaetsstr. 150, Building MA, Level 5, 44780 Bochum, Germany; (J.G.); (J.T.); (V.M.); (V.T.)
| | - Verena Theis
- Department of Cytology, Institute of Anatomy, Ruhr-University Bochum, Universitaetsstr. 150, Building MA, Level 5, 44780 Bochum, Germany; (J.G.); (J.T.); (V.M.); (V.T.)
| | - Carsten Theiss
- Department of Cytology, Institute of Anatomy, Ruhr-University Bochum, Universitaetsstr. 150, Building MA, Level 5, 44780 Bochum, Germany; (J.G.); (J.T.); (V.M.); (V.T.)
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Megalencephalic Leukoencephalopathy with Subcortical Cysts Disease-Linked MLC1 Protein Favors Gap-Junction Intercellular Communication by Regulating Connexin 43 Trafficking in Astrocytes. Cells 2020; 9:cells9061425. [PMID: 32521795 PMCID: PMC7348769 DOI: 10.3390/cells9061425] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 05/29/2020] [Accepted: 06/03/2020] [Indexed: 01/06/2023] Open
Abstract
Astrocytes, the most numerous cells of the central nervous system, exert critical functions for brain homeostasis. To this purpose, astrocytes generate a highly interconnected intercellular network allowing rapid exchange of ions and metabolites through gap junctions, adjoined channels composed of hexamers of connexin (Cx) proteins, mainly Cx43. Functional alterations of Cxs and gap junctions have been observed in several neuroinflammatory/neurodegenerative diseases. In the rare leukodystrophy megalencephalic leukoencephalopathy with subcortical cysts (MLC), astrocytes show defective control of ion/fluid exchanges causing brain edema, fluid cysts, and astrocyte/myelin vacuolation. MLC is caused by mutations in MLC1, an astrocyte-specific protein of elusive function, and in GlialCAM, a MLC1 chaperon. Both proteins are highly expressed at perivascular astrocyte end-feet and astrocyte-astrocyte contacts where they interact with zonula occludens-1 (ZO-1) and Cx43 junctional proteins. To investigate the possible role of Cx43 in MLC pathogenesis, we studied Cx43 properties in astrocytoma cells overexpressing wild type (WT) MLC1 or MLC1 carrying pathological mutations. Using biochemical and electrophysiological techniques, we found that WT, but not mutated, MLC1 expression favors intercellular communication by inhibiting extracellular-signal-regulated kinase 1/2 (ERK1/2)-mediated Cx43 phosphorylation and increasing Cx43 gap-junction stability. These data indicate MLC1 regulation of Cx43 in astrocytes and Cx43 involvement in MLC pathogenesis, suggesting potential target pathways for therapeutic interventions.
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Buruiană A, Florian ȘI, Florian AI, Timiș TL, Mihu CM, Miclăuș M, Oșan S, Hrapșa I, Cataniciu RC, Farcaș M, Șușman S. The Roles of miRNA in Glioblastoma Tumor Cell Communication: Diplomatic and Aggressive Negotiations. Int J Mol Sci 2020; 21:ijms21061950. [PMID: 32178454 PMCID: PMC7139390 DOI: 10.3390/ijms21061950] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/05/2020] [Accepted: 03/06/2020] [Indexed: 02/07/2023] Open
Abstract
Glioblastoma (GBM) consists of a heterogeneous collection of competing cellular clones which communicate with each other and with the tumor microenvironment (TME). MicroRNAs (miRNAs) present various exchange mechanisms: free miRNA, extracellular vesicles (EVs), or gap junctions (GJs). GBM cells transfer miR-4519 and miR-5096 to astrocytes through GJs. Oligodendrocytes located in the invasion front present high levels of miR-219-5p, miR-219-2-3p, and miR-338-3p, all related to their differentiation. There is a reciprocal exchange between GBM cells and endothelial cells (ECs) as miR-5096 promotes angiogenesis after being transferred into ECs, whereas miR-145-5p acts as a tumor suppressor. In glioma stem cells (GSCs), miR-1587 and miR-3620-5p increase the proliferation and miR-1587 inhibits the hormone receptor co-repressor-1 (NCOR1) after EVs transfers. GBM-derived EVs carry miR-21 and miR-451 that are up-taken by microglia and monocytes/macrophages, promoting their proliferation. Macrophages release EVs enriched in miR-21 that are transferred to glioma cells. This bidirectional miR-21 exchange increases STAT3 activity in GBM cells and macrophages, promoting invasion, proliferation, angiogenesis, and resistance to treatment. miR-1238 is upregulated in resistant GBM clones and their EVs, conferring resistance to adjacent cells via the CAV1/EGFR signaling pathway. Decrypting these mechanisms could lead to a better patient stratification and the development of novel target therapies.
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Affiliation(s)
- Andrei Buruiană
- Department of Medical Genetics, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (A.B.); (S.O.); (I.H.); (R.C.C.); (M.F.)
| | - Ștefan Ioan Florian
- Department of Neurosurgery, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (Ș.I.F.); (A.I.F.)
- Department of Neurosurgery, Emergency County Hospital, 3-5 Clinicilor Street, 400006 Cluj-Napoca, Romania
| | - Alexandru Ioan Florian
- Department of Neurosurgery, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (Ș.I.F.); (A.I.F.)
- Department of Neurosurgery, Emergency County Hospital, 3-5 Clinicilor Street, 400006 Cluj-Napoca, Romania
| | - Teodora-Larisa Timiș
- Department of Physiology, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania;
| | - Carmen Mihaela Mihu
- Department of Morphological Sciences-Histology, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania;
| | - Maria Miclăuș
- Department of Medical Genetics, Emergency Hospital for Children, 68 Moților Street, 400370 Cluj-Napoca, Romania;
| | - Sergiu Oșan
- Department of Medical Genetics, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (A.B.); (S.O.); (I.H.); (R.C.C.); (M.F.)
| | - Iona Hrapșa
- Department of Medical Genetics, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (A.B.); (S.O.); (I.H.); (R.C.C.); (M.F.)
| | - Radu Constantin Cataniciu
- Department of Medical Genetics, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (A.B.); (S.O.); (I.H.); (R.C.C.); (M.F.)
| | - Marius Farcaș
- Department of Medical Genetics, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania; (A.B.); (S.O.); (I.H.); (R.C.C.); (M.F.)
- Department of Genetics, IMOGEN Research Center, Louis Pasteur Street, 400349 Cluj-Napoca, Romania
| | - Sergiu Șușman
- Department of Morphological Sciences-Histology, Iuliu Hațieganu University of Medicine and Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania;
- Department of Pathology, IMOGEN Research Center, Louis Pasteur Street, 400349 Cluj-Napoca, Romania
- Correspondence:
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[ 18F]FET PET is a useful tool for treatment evaluation and prognosis prediction of anti-angiogenic drug in an orthotopic glioblastoma mouse model. Lab Anim Res 2019; 34:248-256. [PMID: 30671112 PMCID: PMC6333614 DOI: 10.5625/lar.2018.34.4.248] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 12/04/2018] [Accepted: 12/07/2018] [Indexed: 11/21/2022] Open
Abstract
O-2-18F-fluoroethyl-l-tyrosine ([18F]FET) has been widely used for glioblastomas (GBM) in clinical practice, although evaluation of its applicability in non-clinical research is still lacking. The objective of this study was to examine the value of [18F]FET for treatment evaluation and prognosis prediction of anti-angiogenic drug in an orthotopic mouse model of GBM. Human U87MG cells were implanted into nude mice and then bevacizumab, a representative anti-angiogenic drug, was administered. We monitored the effect of anti-angiogenic agents using multiple imaging modalities, including bioluminescence imaging (BLI), magnetic resonance imaging (MRI), and positron emission tomography-computed tomography (PET/CT). Among these imaging methods analyzed, only [18F]FET uptake showed a statistically significant decrease in the treatment group compared to the control group (P=0.02 and P=0.03 at 5 and 20 mg/kg, respectively). This indicates that [18F]FET PET is a sensitive method to monitor the response of GBM bearing mice to anti-angiogenic drug. Moreover, [18F]FET uptake was confirmed to be a significant parameter for predicting the prognosis of anti-angiogenic drug (P=0.041 and P=0.007, on Days 7 and 12, respectively, on Pearson's correlation; P=0.048 and P=0.030, on Days 7 and 12, respectively, on Cox regression analysis). However, results of BLI or MRI were not significantly associated with survival time. In conclusion, this study suggests that [18F]FET PET imaging is a pertinent imaging modality for sensitive monitoring and accurate prediction of treatment response to anti-angiogenic agents in an orthotopic model of GBM.
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