Biomolecular effects of JB1 (an IGF-I peptide analog) in a rat model of oxygen-induced retinopathy

Pediatr Res. 2011 Feb;69(2):135-41. doi: 10.1203/PDR.0b013e318204e6fa.

Abstract

Low-serum IGF-I levels at birth is a risk factor for the development of retinopathy of prematurity in extremely LBW infants. We tested the hypothesis that JB1 (an IGF-I analog) prevents oxygen-induced retinopathy in our rat model. Neonatal rats were exposed to 50% oxygen with brief, clustered, hypoxic (12%) episodes from birth to P14. The pups were treated with s.c. injections of 1) JB1 (1 μg/d) on P1, P2, and P3 (JB1x3); 2) JB1 (1 μg/d) on alternate days from P1 to P13 (JB1x7); or 3) equivalent volume saline. Control littermates were raised in room air (RA) with all conditions identical except for inspired O2. Groups were analyzed after hyperoxia/hypoxia (H/H) cycling at P14 or allowed to recover in RA until P21. Systemic and ocular VEGF, soluble VEGFR-1, and IGF-I; retinal vasculature; and gene profile of retinal angiogenesis were assessed. JB1x3 was more effective with associated increases in sVEGFR-1 and decreased retinal pathologies than JB1x7. We conclude that early short-term exposure to systemic JB1 treatment normalizes retinal abnormalities seen with H/H cycling, an effect that may involve sVEGFR-1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Disease Models, Animal
  • Drug Administration Schedule
  • Gene Expression Regulation / drug effects
  • Humans
  • Hyperoxia / blood
  • Hyperoxia / complications*
  • Hyperoxia / physiopathology
  • Infant, Newborn
  • Injections, Subcutaneous
  • Insulin-Like Growth Factor I / administration & dosage
  • Insulin-Like Growth Factor I / analogs & derivatives
  • Insulin-Like Growth Factor I / pharmacology*
  • Insulin-Like Growth Factor II / metabolism
  • Neovascularization, Pathologic / blood
  • Neovascularization, Pathologic / drug therapy*
  • Neovascularization, Pathologic / etiology
  • Neovascularization, Pathologic / genetics
  • Neovascularization, Pathologic / physiopathology
  • Peptides / administration & dosage
  • Peptides / pharmacology*
  • RNA, Messenger / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Retinal Vessels / drug effects*
  • Retinal Vessels / metabolism
  • Retinal Vessels / physiopathology
  • Retinopathy of Prematurity / blood
  • Retinopathy of Prematurity / drug therapy*
  • Retinopathy of Prematurity / etiology
  • Retinopathy of Prematurity / genetics
  • Retinopathy of Prematurity / physiopathology
  • Time Factors
  • Vascular Endothelial Growth Factor A / blood
  • Vascular Endothelial Growth Factor Receptor-1 / blood

Substances

  • Peptides
  • RNA, Messenger
  • Vascular Endothelial Growth Factor A
  • vascular endothelial growth factor A, rat
  • Insulin-Like Growth Factor I
  • Insulin-Like Growth Factor II
  • Flt1 protein, rat
  • Vascular Endothelial Growth Factor Receptor-1