Ismail Zaitoun, PhD
Credentials: Associate Scientist, Department of Ophthalmology & Visual Sciences
1111 Highland Ave
Madison, WI 53705
BS Biology, Jordan University of Science & Technology, Irbid, Jordan, 1998
MS Genetics, University of Jordan, Amman, Jordan, 2002
PhD Genetics, Epigenetics, and Developmental Biology, UW-Madison, Madison, WI, 2008
Ismail Zaitoun investigates the impact of hypoxic-ischemic insult on retinal vascular integrity and function. A great majority of surviving children with hypoxic-ischemic encephalopathy (HIE) display visual impairments. These impairments are usually associated with injuries to certain parts of cerebral visual systems. In addition, emerging evidence suggests neuronal damage in the retina following HIE. However, how these changes are brought up in the retina, and whether retinal vascular damage contributes to the compromised vision remains poorly understood. Dr. Zaitoun’s studies show a significant defect in the retinal vascularization in animals subjected to HIE; blood vessels on the surface of the retina are pathologically enlarged with signs of degenerations, and the blood vessels deep in the retina fell short of covering the whole periphery. The earliest signs of retinal vascular damage are apparent as early as one-day post HIE insults. Moreover, he found few signs of recovery from the acquired vascular lesions at least until 100 days post- HIE insult day, the last day tested. Currently, Dr. Zaitoun is studying the effects of ischemic stroke insult on the neurovascular unit at the cellular level (endothelial cells, pericytes, and astrocytes), both in vivo and in vitro. At the molecular level, he is testing the potential contribution of the hypoxia-inducible factors (HIFs) to the retinal vascular damages caused by hypoxic-ischemic insults. In collaboration with Dr. Chris Sorenson, he is investigating the contribution of both pro- and anti-apoptotic proteins to the eye vasculature under developmental and pathologic conditions.