Neuroprotective Effect of Intravitreal Triamcinolone Acetonide against Photoreceptor Apoptosis in a Rabbit Model of Subretinal Hemorrhage

Abstract

Photoreceptor toxicity caused by SRH occurs at least in part by apoptosis and is associated with iron migration to the photoreceptor layer. Treatment with IVTA reduced photoreceptor loss and apoptosis, indicating a neuroprotective action. Therapies to target SRH may augment anti-VEGF treatments in exudative age-related macular degeneration and other diseases of choroidal neovascularization.

Signal Transduction Pathways in use of Dexamethasone Implant in the Eye

“…Glucocorticoids also have protective (anti-apoptotic) effects on the neural retina. It was seen on rabbit models that IVTA injection protected the retinal photoreceptors from apoptosis after sub retinal hemorrhage [120]. A similar result was seen in the reduction by glucocorticoids of photoreceptor apoptosis induced with light in rabbits, most likely through activator protein-1 suppression with the GR activation [121].…”

Retinal Detachment Model in Rodents by Subretinal Injection of Sodium Hyaluronate

“…Several factors can influence the effect of RD on the detached retina, including both subretinal hemorrhage and the height and persistence of RD [16][17][18][19][20][21] . Photoreceptor cell death increases with increasing height of RD 16,17 , and photoreceptor cell damage may be more extensive because of reduced diffusion of oxygen and essential nutrients from the choriocapillaris with higher RD compared to shallow RD.…”

“…Photoreceptor cell death increases with increasing height of RD 16,17 , and photoreceptor cell damage may be more extensive because of reduced diffusion of oxygen and essential nutrients from the choriocapillaris with higher RD compared to shallow RD. Subretinal hemorrhage is also toxic for photoreceptor cells [18][19][20][21] ; possible mechanisms of this toxicity in the detached retina include hypoxia and metabolic disruption by subretinal hemorrhage as a diffusion barrier, and direct neurotoxicity induced by blood components (such as iron). Lens injury, which has been reported to have a protective effect on retinal ganglion cells 23 , may also affect photoreceptor cell death after induction of RD.…”

“…Consistent with these reports, our previous experiments showed more photoreceptor death in bullous RDs than shallow RDs. It has also been reported that subretinal hemorrhage is toxic for photoreceptor cells and affects photoreceptor cell death [18][19][20][21] . Likewise, we have observed more photoreceptor death in RDs with subretinal hemorrhage than RDs without subretinal hemorrhage.…”

Treatment of a Patient with Multiple Cutaneous Piloleiomyoma-Related Pain with a Local Injection of Triamcinolone Acetonide

“…Considering the safety profile of TA for use in human eyes, as well as the drug's neuroprotective effect [15,16], we locally injected TA into the lesions of cutaneous piloleiomyomas. As a result, this treatment is not only effective but also safe.…”