title: Efficacy of Intravitreal injection of 2-Methoxyestradiol in regression of neovascularization of a retinopathy of prematurity rat model.
abstract: BACKGROUND
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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).
  
  
  CONCLUSIONS
  Intravitreal injection of 2-Methoxyestradiol nanoemulsion is a promising effective method in reduction of neovascularization of a ROP rat model.
authors.affiliation: Ophthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt. Dr_azza_22@hotmail.com.|, 10th Fawzy Elmoteay Street, Heliopolis, Cairo, 11361, Egypt. Dr_azza_22@hotmail.com.
authors.forename: Azza Mohamed Ahmed
authors.initials: AM
authors.lastname: Said
authors.affiliation: Ophthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: Rania Gamal Eldin
authors.initials: RG
authors.lastname: Zaki
authors.affiliation: Anatomy and Embryology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: Rania A
authors.initials: RA
authors.lastname: Salah Eldin
authors.affiliation: Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt.
authors.forename: Maha
authors.initials: M
authors.lastname: Nasr
authors.affiliation: Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt.
authors.forename: Samar Saad
authors.initials: SS
authors.lastname: Azab
authors.affiliation: Ophthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: Yaser Abdelmageuid
authors.initials: YA
authors.lastname: Elzankalony
mesh_terms: D000077584:2-Methoxyestradiol; D000818:Animals; D000831:Animals, Newborn; D004195:Disease Models, Animal; D018450:Disease Progression; D004958:Estradiol / Q000008:administration & dosage / Q000031:analogs & derivatives*; D007150:Immunohistochemistry; D058449:Intravitreal Injections; D008297:Male; D010784:Photomicrography; D011446:Prospective Studies; D051381:Rats; D017207:Rats, Sprague-Dawley; D015861:Retinal Neovascularization / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology; D012171:Retinal Vessels / Q000473:pathology*; D012178:Retinopathy of Prematurity / Q000150:complications / Q000188:drug therapy* / Q000473:pathology; D050257:Tubulin Modulators / Q000008:administration & dosage; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors
chemical_list: D050257:Tubulin Modulators; D042461:Vascular Endothelial Growth Factor A; D004958:Estradiol; D000077584:2-Methoxyestradiol
keywords: 2-methoxyestradiol; GFAP; Neovascularization; Retinopathy of prematurity; VEGF