Purchase this article with an account.
M. Ueki, S. Saraswathy, N. A. Rao; Neuroglobin Protects Retinal Neurons in Ischemia/Reperfusion Injury. Invest. Ophthalmol. Vis. Sci. 2009;50(13):2773.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
We previously reported increased expression of neuroglobin in the retina of enucleated human globes with glaucoma, suggesting such expression may help protect retinal neurons against ischemic or oxidative stress injury. In the present study, we investigated the protective effect of neuroglobin in retinal ischemia/reperfusion injury, using transgenic mice overexpressing neuroglobin.
Retinal ischemia was induced as previously reported in neuroglobin overexpressing ( Ngb+/+) mice (kindly provided by Dr. D.A Greenberg, Buck Institute for Age Research, CA ) and wild type controls. The left eye anterior chamber was cannulated with a 30G infusion needle connected to a physiological saline reservoir by silastic tubing. The intraocular pressure of the eye was raised to 110mmHg for 60 min by elevating the saline reservoir. Retinal ischemia was confirmed by indirect ophthalmoscopy. Six wild type mice and six Ngb+/+ mice with ocular ischemia were killed on day 3 and their retinas were analyzed for leucocytic infiltration using anti-CD45 and 8-OHdG staining to determine oxidative DNA damage. Another group of six wild type mice and six Ngb+/+ mice with ocular ischemia were killed on day 7 and their eyes were subjected to 8-OHdG staining and TUNEL assay. Morphometric analysis was used to determine the number of cells in ONL, INL and GCL and the retinal thickness.
On day 3, wild type retina showed infiltration of CD45-positive cells. Positive staining for 8-OHdG was detected in the GCL of the wild type on days 3 and 7 post ischemia. Such staining was absent in the Ngb+/+ mice. On day 7 post ischemia in the wild type mice the ganglion cells showed immunoreactivity for 8-OHdG, and apoptotic cells were seen in the ONL and GCL. Such positive results were absent in the Ngb+/+ mice. There was a significant reduction in ONL, INL, GCL cells and retinal layer thickness in post ischemia retina of the wild type mice compared to the normal retina; however, there was no significant difference in the ischemia retina of Ngb+/+ mice compared to normal retina.
These results reveal a protective role of neuroglobin in the prevention of apoptosis-mediated retinal damage in ischemia/reperfusion injury.
This PDF is available to Subscribers Only