Protective effects of curcumin on ischemic reperfusion of rat retina

Abstract

Ischemic reperfusion is an optic neuropathy in which photoreceptor cells may die through an apoptotic process. Free radicals are involved in the apoptotic process of ischemic reperfusion disorders. Previous research indicates that curcumin is an antioxidant found in plants which reduces neurodegenerative changes in aged animals. The purpose of this research was to survey whether curcumin has preventive effects on ischemic reperfusion of the retina. Twenty male Wistar rats were grouped into four (n = 5): 1, control group; 2, ischemic reperfusion group; 3, experimental group II: received 0.01% curcumin in diet (low dose) for 2 days before ischemic reperfusion; 4, experimental group III: received 0.25% curcumin in diet (high dose) for 2 days before ischemic reperfusion. The eye was enucleated and the retina separated. Routine tissue processing in transmission electron microscopy was done. Results showed that ischemic reperfusion created major signs of injury in the photoreceptor layer such as disappearance of the outer segment, cell swelling, and karyolitic and pyknotic nuclei, but cell swelling and karyolitic nuclei were not seen after receiving a low dose of curcumin. Also, the photoreceptor layer appeared normal after receiving a high dose of curcumin, but decreased vacuolization and dark and inactive nuclei were obvious. This study concluded that a high dose of curcumin confers a more preventive effect on retinal injury by ischemic reperfusion than a low dose.