Journal
EXPERIMENTAL EYE RESEARCH
Volume 88, Issue 6, Pages 1051-1064Publisher
ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD
DOI: 10.1016/j.exer.2009.01.007
Keywords
CNTF; Stat3; light-induced retinal damage; retinal regeneration; Muller glia; neuroprotection; zebrafish; SB 203580; MAP kinase inhibitor
Categories
Funding
- University of Notre Dame's Center for Zebrafish Research
Ask authors/readers for more resources
Ciliary neurotrophic factor (CNTF) acts in several processes in the vertebrate retina, including neuroprotection of photoreceptors in the stressed adult retina and regulation of neuronal progenitor cell proliferation during retinal development. However, the signaling pathway it utilizes (Jak/Scat, MAPK, or Akt) in these processes is ambiguous. Because dark-adapted albino zebrafish exhibit light-induced rod and cone cell death and subsequently regenerate the lost photoreceptor cells, zebrafish should be a useful model to study the role of CNTF in both neuroprotection and neuronal progenitor cell proliferation. We therefore investigated the potential roles of CNTF in both the undamaged and light-damaged adult zebrafish retinas. Intraocular injection of CNTF suppressed light-induced photoreceptor cell death, which then failed to exhibit the regeneration response that is marked by proliferating Muller glia and neuronal progenitor cells. Inhibiting the MAPK signaling pathway, but neither the Stat3 nor Akt pathways, significantly reduced the CNTF-mediated neuroprotection of light-induced photoreceptor cell death. Intraocular injection of CNTF into non-light-treated (undamaged) eyes mimicked constant intense light treatment by increasing Stat3 expression in Muller glia followed by increasing the number of proliferating Muller glia and neuronal progenitors. Knockdown of Stat3 expression in the CNTF-injected non-light-treated retinas significantly reduced the number of proliferating Muller glia, while coinjection of CNTF with either MAPK or Akt inhibitors did not inhibit the CNTF-induced Muller glia proliferation. Thus, CNTF utilizes a MAPK-dependant signaling pathway in neuroprotection of light-induced photoreceptor cell death and a Stat3-dependant signaling pathway to stimulate Muller glia proliferation. (C) 2009 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available