Ischemic Preconditioning and the Role of Protein Kinase C in Cultured Retinal Ganglion Cell Line.
10.3341/jkos.2008.49.6.979
- Author:
Kyoung Doo NA
1
;
Sung Yong KANG
;
Gong Je SEONG
;
Samin HONG
;
Mi Jin CHUN
;
Chan Yun KIM
Author Information
1. Department of Ophthalmology, Yonsei University College of Medicine, The Institute of Vision Research, Seoul, Korea. kcyeye@yuhs.ac
- Publication Type:Original Article
- Keywords:
Ischemic preconditioning;
Oxidative stress;
Protein kinase C;
RGC-5
- MeSH:
Axons;
Cell Line;
Hydrogen;
Hydrogen Peroxide;
Ischemic Preconditioning;
Isoenzymes;
Neurons;
Neuroprotective Agents;
Oxidative Stress;
Oxygen;
Protein Isoforms;
Protein Kinase C;
Protein Kinases;
Proteins;
Retinal Ganglion Cells;
Retinaldehyde;
RNA, Messenger;
Staurosporine
- From:Journal of the Korean Ophthalmological Society
2008;49(6):979-986
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: To investigate the cellular protective effects of hypoxic preconditioning against oxidative stress in a staurosporine-differentiated RGC-5 cell line and the relevance of protein kinase C subtype expression. METHODS: The minimum staurosporine concentration and exposure time necessary to morphologically fully differentiate RGC-5 cells were determined. Cytotoxic injury was provided by oxidative stress with 800 micrometer hydrogen peroxide (H2O2) for 15 hours to morphologically fully-differentiated cells. The cytoprotective effect of hypoxic preconditioning was found by exposing the cell line to 0.3% oxygen for different periods of time. Quantifiable changes in the expression of mRNAs and proteins of the isoenzymes alpha, beta, gamma, delta, epsilon, zeta of protein kinase C were determined before and after 1, 2, 15, and 24 hours of hypoxic preconditioning. RESULTS: Axonal growth in RGC-5 cells after the induction of differentiation with staurosporine caused these cells to resemble neurons. The minimal concentration and exposure time to staurosporine that evoked full differentiation of RGC-5 cells was exposure to 2 micrometer staurosporine for 1 hour. An LDH assay demonstrated that hypoxic preconditioning had neuroprotective effects against hydrogen peroxide-induced oxidative stress. Protein and mRNA levels of PKC isoforms alpha and epsilon increased after preconditioning. CONCLUSIONS: Hypoxic preconditioning of staurosporine-differentiated RGC-5 cells had a cytoprotective effect against oxidative stress. The associated increase of mRNA and proteins of PKC isoenzymes alpha and epsilon suggest some functional relevance of these isoenzymes to the cytoprotective effects conferred by hypoxic preconditioning.
