Protective mechanism of agmatine pretreatment on RGC-5 cells injured by oxidative stress
Braz. j. med. biol. res
; 43(4): 356-358, Apr. 2010. graf
Article
in English
| LILACS
| ID: lil-543577
Responsible library:
BR1.1
ABSTRACT
Agmatine has neuroprotective effects on retinal ganglion cells (RGCs) as well as cortical and spinal neurons. It protects RGCs from oxidative stress even when it is not present at the time of injury. As agmatine has high affinity for various cellular receptors, we assessed protective mechanisms of agmatine using transformed RGCs (RGC-5 cell line). Differentiated RGC-5 cells were pretreated with 100 ìM agmatine and consecutively exposed to 1.0 mM hydrogen peroxide (H2O2). Cell viability was determined by measuring lactate dehydrogenase (LDH), and the effects of selective alpha 2-adrenergic receptor antagonist yohimbine (0-500 nM) and N-methyl-D-aspartic acid (NMDA) receptor agonist NMDA (0-100 µM) were evaluated. Agmatines protective effect was compared to a selective NMDA receptor antagonist MK-801. After a 16-h exposure to H2O2, the LDH assay showed cell loss greater than 50 percent, which was reduced to about 30 percent when agmatine was pretreated before injury. Yohimbine almost completely inhibited agmatines protective effect, but NMDA did not. In addition, MK-801 (0-100 µM) did not significantly attenuate the H2O2-induced cytotoxicity. Our results suggest that neuroprotective effects of agmatine on RGCs under oxidative stress may be mainly attributed to the alpha 2-adrenergic receptor signaling pathway.
Full text:
Available
Collection:
International databases
Database:
LILACS
Main subject:
Retinal Ganglion Cells
/
Oxidative Stress
/
Neuroprotective Agents
/
Agmatine
Limits:
Animals
Language:
English
Journal:
Braz. j. med. biol. res
Journal subject:
Biology
/
Medicine
Year:
2010
Document type:
Article
Affiliation country:
South Korea
Institution/Affiliation country:
Yonsei University College of Medicine/KR