PUBLICATION

Expression of adenosine receptors and vegf during angiogenesis and its inhibition by pentoxifylline-A study using zebrafish model

Authors
Nathan, J.R., Lakshmanan, G., Michael, F.M., Seppan, P., Ragunathan, M.
ID
ZDB-PUB-161103-7
Date
2016
Source
Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie   84: 1406-1418 (Journal)
Registered Authors
Keywords
Adenosine receptors, Angiogenesis, Epiboly, PTX, Vertebrate model
MeSH Terms
  • Angiogenesis Inhibitors/pharmacology*
  • Animals
  • Dose-Response Relationship, Drug
  • Gene Expression Regulation
  • Models, Animal*
  • Neovascularization, Pathologic/metabolism*
  • Pentoxifylline/pharmacology*
  • Receptors, Purinergic P1/biosynthesis*
  • Retina/drug effects
  • Retina/metabolism
  • Vascular Endothelial Growth Factor A/biosynthesis*
  • Zebrafish
PubMed
27802896 Full text @ Biomed. Pharmacother.
Abstract
Angiogenesis, formation of new blood vessels is an important process involved in neovascular diseases and tumor progression. Understanding and defining novel therapeutic targets of neovascular diseases like retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration have been hindered by a lack of appropriate animal models. Zebrafish provides an excellent vertebrate model to study above disorders since its circulatory system and retinal layers are similar to mammals. Adenosine is a known mediator of angiogenesis in hypoxic condition and adenosine receptor antagonists such as theophylline, theobromine are known to exert antiangiogenic properties. We evaluated the anti-angiogenic potential of a methylxanthine pentoxifylline (PTX) with various concentrations (0.1-1mM) at 50% epiboly stage (5.2 hpf) of zebrafish embryos and studied the mRNA expression of major angiogenic factors like vegfaa and its receptors under normal conditions and when treated with an adenosine analog NECA (5'-N-ethylcarboxamidoadenosine). Upregulation of adenosine receptors, hif-1α and vegfaa by NECA could possibly mimic hypoxic condition, but PTX downregulated vegfaa and other growth factors at 1mM concentration. Vegfa protein expression was also downregulated by PTX in the retina and the compound did not damage the retinal cells. Embryos treated with PTX generated abnormal phenotypic variants with poor vasculature, tail bending and developmental delay at 1mM. Survival rates, heart rate and hatching rates were also significantly lower. Targeting the vegf signaling pathway with small molecules inhibiting adenosine receptors in addition to antagonizing vegf might be a promising approach to treat neovascular diseases of the retina and also tumors.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping