1
|
Beazley-Long N, Hua J, Jehle T, Hulse RP, Dersch R, Lehrling C, Bevan H, Qiu Y, Lagrèze WA, Wynick D, Churchill AJ, Kehoe P, Harper SJ, Bates DO, Donaldson LF. VEGF-A165b is an endogenous neuroprotective splice isoform of vascular endothelial growth factor A in vivo and in vitro. THE AMERICAN JOURNAL OF PATHOLOGY 2013; 183:918-29. [PMID: 23838428 PMCID: PMC3763768 DOI: 10.1016/j.ajpath.2013.05.031] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 05/19/2013] [Accepted: 05/31/2013] [Indexed: 01/13/2023]
Abstract
Vascular endothelial growth factor (VEGF) A is generated as two isoform families by alternative RNA splicing, represented by VEGF-A165a and VEGF-A165b. These isoforms have opposing actions on vascular permeability, angiogenesis, and vasodilatation. The proangiogenic VEGF-A165a isoform is neuroprotective in hippocampal, dorsal root ganglia, and retinal neurons, but its propermeability, vasodilatatory, and angiogenic properties limit its therapeutic usefulness. In contrast, a neuroprotective effect of endogenous VEGF-A165b on neurons would be advantageous for neurodegenerative pathologies. Endogenous expression of human and rat VEGF-A165b was detected in hippocampal and cortical neurons. VEGF-A165b formed a significant proportion of total VEGF-A in rat brain. Recombinant human VEGF-A165b exerted neuroprotective effects in response to multiple insults, including glutamatergic excitotoxicity in hippocampal neurons, chemotherapy-induced cytotoxicity of dorsal root ganglion neurons, and retinal ganglion cells (RGCs) in rat retinal ischemia-reperfusion injury in vivo. Neuroprotection was dependent on VEGFR2 and MEK1/2 activation but not on p38 or phosphatidylinositol 3-kinase activation. Recombinant human VEGF-A165b is a neuroprotective agent that effectively protects both peripheral and central neurons in vivo and in vitro through VEGFR2, MEK1/2, and inhibition of caspase-3 induction. VEGF-A165b may be therapeutically useful for pathologies that involve neuronal damage, including hippocampal neurodegeneration, glaucoma diabetic retinopathy, and peripheral neuropathy. The endogenous nature of VEGF-A165b expression suggests that non-isoform-specific inhibition of VEGF-A (for antiangiogenic reasons) may be damaging to retinal and sensory neurons.
Collapse
Affiliation(s)
- Nicholas Beazley-Long
- Microvascular Research Laboratories, School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom
| | - Jing Hua
- Microvascular Research Laboratories, School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom
| | - Thomas Jehle
- University Eye Hospital, Albert-Ludwigs University, Freiburg, Germany
| | - Richard P. Hulse
- School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom
| | - Rick Dersch
- Department of Neurology, University Hospital Freiburg, Freiburg, Germany
| | | | - Heather Bevan
- Microvascular Research Laboratories, School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom
| | - Yan Qiu
- Microvascular Research Laboratories, School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom
| | - Wolf A. Lagrèze
- University Eye Hospital, Albert-Ludwigs University, Freiburg, Germany
| | - David Wynick
- Department of Neurology, University Hospital Freiburg, Freiburg, Germany
| | | | - Patrick Kehoe
- Dementia Research Group, John James Laboratories, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
| | - Steven J. Harper
- Microvascular Research Laboratories, School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom
| | - David O. Bates
- Microvascular Research Laboratories, School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom
| | - Lucy F. Donaldson
- School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom
| |
Collapse
|
2
|
Dong K, Ahmed AK, Qu T, Sugioka K, Yamada K, Yamadori T. Retrograde fluorescent double-labeling study of bilaterally projecting retinal ganglion cells in albino rats at different stages of development. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 1996; 95:55-62. [PMID: 8873976 DOI: 10.1016/0165-3806(96)00056-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Injection of the fluorescent tracers 10% Evans blue (EB) and 4% fluoro-gold (FG) into the right and the left dorsal lateral geniculate nucleus, respectively, of albino rats at different stages of development demonstrated the presence of double-labeled retinal ganglion cells that projected bilaterally into both the dorsal lateral geniculate nuclei (dLGN). Findings confirmed that the distribution of these double-labeled cells was gradually reduced after birth, being confined to the peripheral temporoventral quarter (temporal-ventral crescent) of the retina after postnatal day 15. We estimated the proportion of double-labeled cells to total labeled cells in the same area at different stages of development (0-90 days); values ranged from 35.3% in the neonate to 5.27% in the adult rat which suggests that the majority of double-labeled cells and/or their axons were lost early in development. That a small number of ganglion cells were observed to project bilaterally in the adult rats suggested that these cells conduct the same visual information to both hemispheres throughout the animal's life.
Collapse
Affiliation(s)
- K Dong
- First Department of Anatomy, Kobe University School of Medicine, Japan
| | | | | | | | | | | |
Collapse
|
3
|
Farid Ahmed AK, Dong K, Yamadori T. A retrograde double-labeling study of uni- and bilaterally projecting retinal ganglion cells that project to the superior colliculi after unilateral eye removal at birth in the albino rat. Brain Res 1995; 704:307-12. [PMID: 8788927 DOI: 10.1016/0006-8993(95)01282-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
By injecting Fluoro-Gold and Evans-Blue into the right and left superior colliculi of the normal adult albino rats, bilaterally projecting retinal ganglion cells were labeled in the ventrotemporal crescent accounting for 37.9% of all the labeled cells, whereas in 0- and 5-day unilaterally enucleated rats these were found in the lower half of the retina accounting for 64.8% and 80.6%, respectively. Furthermore, they tended to have larger somata (type I cells).
Collapse
Affiliation(s)
- A K Farid Ahmed
- First Department of Anatomy, Kobe University School of Medicine, Japan
| | | | | |
Collapse
|