Ocular neovascularization. Experimental animal model and studies on angiogenic factor(s)

Animal models for metabolic, neuromuscular and ophthalmological rare diseases

Animal models are important tools in the discovery and development of treatments for rare diseases, particularly given the small populations of patients in which to evaluate therapeutic candidates. Here, we provide a compilation of mammalian animal models for metabolic, neuromuscular and ophthalmological orphan-designated conditions based on information gathered by the European Medicines Agency's Committee for Orphan Medicinal Products (COMP) since its establishment in 2000, as well as from a review of the literature. We discuss the predictive value of the models and their advantages and limitations with the aim of highlighting those that are appropriate for the preclinical evaluation of novel therapies, thereby facilitating further drug development for rare diseases.

Review of the ocular angiogenesis animal models

Increasing interest in developing reliable and reproducible models to study angiogenesis has emerged due to recent advances in the treatment of eye disease with pathologic angiogenesis. This review provides a summary of the principal ocular animal models for angiogenesis. Models of anterior segment neovascularization include the corneal micropocket assay, used to study the influence of specific molecules/proteins in angiogenesis, and corneal chemical and suture induced injury, which mimic more closely the complex nature of the human disease. Angiogenesis models of the posterior segment include the well-known laser-induced injury of the choroid/Bruch's membrane, as well as the oxygen induced retinopathy and models of injections of pro-angiogenic/inflammatory molecules. In addition, knockout or knock-in transgenic mice provide powerful tools in studying the role of specific proteins in angiogenesis.

Capillary endothelial-cell mitogenic activity in experimental branch vein occlusion

Since the 1940s, the major hypothesis regarding the stimulus for neovascularization occurring in diabetic retinopathy and other "ischemic" retinopathies has involved the release of a soluble angiogenic factor from the ischemic retina. We sought to test this by measuring the endothelial mitogenic activity that could be extracted from an ischemic retina caused by branch vein occlusion in the cat. We found that the extractable endothelial-cell mitogenic activity from normal retinal areas was similar to that in ischemic areas at 1, 2, and 7 days after the occlusion. In the area of occluded veins, the oxygen partial pressure was low (7 +/- 7 mm Hg) compared with the normal value (23 +/- 8 mm Hg). The data did not show any increase in soluble mitogenic factor release from the ischemic retina versus normal retinal areas under the conditions of this experiment.