The online version of this article (doi:10.1186/s12886-017-0433-3) contains supplementary material, which is available to authorized users.
Retinopathy of prematurity (ROP) is one of the targets for early detection and treatment to prevent childhood blindness in world health organization programs. The purpose of study was to evaluate the efficacy of intravitreal injection of 2-Methoxyestradiol (2-ME) nanoemulsion in regressing neovascularization of a ROP rat model.
A prospective comparative case - control animal study conducted on 56 eyes of 28 healthy new born Sprague Dawley male albino rat. ROP was induced in 21 rats then two concentrations of 2-ME nanoparticles were injected in right eyes of 14 rats (low dose; study group I, high dose; study group II). A blank nanoemulsion was injected in the right eyes of seven rats (control positive group I). No injections performed in contralateral left eyes (control positive group II). Seven rats (14 eyes) were kept in room air (control negative group). On postnatal day 17, eyeballs were enucleated. Histological structure of the retina was examined using Hematoxylin and eosin staining. Vascular endothelial growth factor (VEGF) and glial fibrillary acidic protein (GFAP) expressions were detected by immunohistochemical studies.
Intravitreal injection of 2-ME (in the two concentrations) caused marked regression of the new vascular tufts on the vitreal side with normal organization and thickness of the retina especially in study group II, which also show negative VEGF immunoreaction. Positive GFAP expression was detected in the control positive groups and study group (I).
Intravitreal injection of 2-Methoxyestradiol nanoemulsion is a promising effective method in reduction of neovascularization of a ROP rat model.
Additional file 1: Data.xlsx includes raw data of ROP animal models that were injected inravitreally using two different concentrations of 2-Methoxyestradiol (2-ME) nanoparticles in order to produce regression of neovascularization (NVs) and the data of the control groups. The file includes one data sheet. The sheet includes data of each animal in terms of endothelial cell count on vitreal side, percentage of vascular endothelial growth factor (VEGF) expression and percentage of glial fibrillary acidic protein (GFAP) expression before and after treatment. (XLSX 12 kb)
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- Efficacy of Intravitreal injection of 2-Methoxyestradiol in regression of neovascularization of a retinopathy of prematurity rat model
Azza Mohamed Ahmed Said
Rania Gamal Eldin Zaki
Rania A. Salah Eldin
Samar Saad Azab
Yaser Abdelmageuid Elzankalony
- BioMed Central