[The treatment of retinal apoptosis by Caspase 3 inhibitor Ac-DEVD-CHO in experimental myopia].
OBJECTIVE
To investigate the mechanism of retinal apoptosis in chick experimental myopia and the therapy of Caspase 3 inhibitor Ac-DEVD-CHO.


METHODS
Chick myopia was induced by lid-suture. After Ac-DEVD-CHO had been injected into vitreous, myopia was confirmed by optometry. Subsequently, chick eyeballs removed were measured its extro-dimensions, and the change of fundus were observed. Retinal apoptotic cells were determined by electron microscopy, TUNEL technique and flow cytometry. Retinal Caspase 3 proteins and its activities were measured by immunohistochemistry, flow cytometry and a colorimetric method using Ac-DEVD-pNA as a substrate.


RESULTS
Ocular diopters and extro-diameters in all sutured eyes remarkly increased in comparison with its control eyes at 12 weeks after lid-suture. Lacquer crack lesions were found in 41 of 90 sutured eyes (45.56%). Apoptotic cells were observed in retinal outer and inner nuclear layer of the sutured eyes, and its apoptotic rate was significantly more than in control eyes (P < 0.05). Moreover, the expression of retinal Caspase 3 proteins and its activities were increased. After Ac-DEVD-CHO was injected into vitreous, the decrease of retinal apoptotic rate, Caspase 3 proteins and its activities was found. The treated effect of Ac-DEVD-CHO was in a dose dependent manner.


CONCLUSIONS
Caspase 3 plays an important role in retinal apoptosis of chick myopia. Ac-DEVD-CHO can effectively ameliorate retinal apoptosis by blocked the effect of Caspase 3.
Liu
Shuang-zhen
SZ
Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha 410008, China. liushzhxy@163.com
Mao
Jun-feng
JF
Wen
Dan
D
Tan
Xing-ping
XP
Fu
Chun-yan
CY
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D002645:Chickens; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology*; D009216:Myopia / Q000473:pathology*; D009842:Oligopeptides / Q000494:pharmacology*; D012160:Retina / Q000378:metabolism / Q000473:pathology*
D015853:Cysteine Proteinase Inhibitors; D009842:Oligopeptides; C099158:acetyl-aspartyl-glutamyl-valyl-aspartal; D053148:Caspase 3