Investigation of the intranasal delivery method as a means of targeting therapeutic agents to the Injured retina and optic nerve.

Abstract

Ischemic optic neuropathy (ION) is a visually devastating disease process in which there is disruption of arterial blood flow to the optic nerve head. ION, both anterior and posterior, is the most common cause of sudden optic nerve-related vision loss in the developed world. In addition, traumatic optic neuropathy (TON), caused by blunt trauma to the orbit and/or face, can cause tractional, compressive, or ischemic injuries to the optic nerve as well. These types of injuries to the optic nerve can ultimately result in the death of retinal ganglion cells in the retina and, consequently, the functional loss of vision. Currently, there is no effective treatment for these types of injury. There are several issues that stand in the way of adopting treatment modalities for injuries to the optic nerve and retina. Many potential therapeutic drugs are unable to gain access to the affected cells due to the protective blood-retinal and blood-brain barrier. Neurotrophic factors are endogenous large molecular weight neuroprotective proteins that, upon injury, are released in an autocrine and paracrine fashion to reduce apoptotic cellular death. However, these factors possess inherent molecular characteristics that impede their transport through the protective blood-brain barrier. Therefore, the ability to bypass the blood-brain barrier using a non-invasive means would have great clinical potential. This study examined the viability of the intranasal delivery method as a means of targeting therapeutic agents to the injured retina and optic nerve.