Comparison of pre-treatment and post-treatment use of selenium in retinal ischemia reperfusion injury.
OBJECTIVE
To investigate the effects of selenium in rat retinal ischemia reperfusion (IR) model and compare pre-treatment and post-treatment use.


METHODS
Selenium pre-treatment group (n=8) was treated with intraperitoneal (i.p.) selenium 0.5 mg/kg for 7d and terminated 24h after the IR injury. Selenium post-treatment group (n=8) was treated with i.p. selenium 0.5 mg/kg for 7d after the IR injury with termination at the end of the 7d period. Sham group (n=8) received i.p. saline injections identical to the selenium volume for 7d with termination 24h after the IR injury. Control group (n=8) received no intervention. Main outcome measures were retina superoxide dismutase (SOD), glutathione (GSH), total antioxidant status (TAS), malondialdehyde (MDA), DNA fragmentation levels, and immunohistological apoptosis evaluation.


RESULTS
Compared to the Sham group, selenium pre-treatment had a statistical difference in all parameters except SOD. Post-treatment selenium also resulted in statistical differences in all parameters except the MDA levels. When comparing selenium groups, the pre-treatment selenium group had a statistically higher success in reduction of markers of cell damage such as MDA and DNA fragmentation. In contrast, the post-selenium treatment group had resulted in statistically higher levels of GSH. Histologically both selenium groups succeeded to limit retinal thickening and apoptosis. Pre-treatment use was statistically more successful in decreasing apoptosis in ganglion cell layer compared to post-treatment use.


CONCLUSIONS
Selenium was successful in retinal protection in IR injuries. Pre-treatment efficacy was superior in terms of prevention of tissue damage and apoptosis.
Department of Ophthalmology, Faculty of Medicine, Balikesir University, Balikesir 10010, Turkey.
Alper
A
Yazici
Department of Biochemistry, Faculty of Veterinary, Balikesir University, Balikesir 10010, Turkey.
Hasan
H
Aksit
Department of Ophthalmology, Faculty of Medicine, Balikesir University, Balikesir 10010, Turkey.
Esin Sogutlu
ES
Sari
Department of Histology and Embryology, Faculty of Medicine, Erciyes University, Kayseri 38010, Turkey.
Arzu
A
Yay
Department of Physiology, Faculty of Medicine, Balikesir University, Balikesir 10010, Turkey.
Haydar Ali
HA
Erken
Department of Pharmacology, Faculty of Veterinary, Balikesir University, Balikesir 10010, Turkey.
Dilek
D
Aksit
Department of Ophthalmology, Faculty of Medicine, Adnan Menderes University, Aydin 09010, Turkey.
Harun
H
Cakmak
Department of Biochemistry, Faculty of Medicine, Balikesir University, Balikesir 10010, Turkey.
Kamil
K
Seyrek
Department of Ophthalmology, Faculty of Medicine, Balikesir University, Balikesir 10010, Turkey.
Sitki Samet
SS
Ermis
apoptosis; ischemia-reperfusion; oxidative stress; post-treatment; pre-treatment; retina; selenium