Assessment of the pharmacological mechanisms of the peptide TnP isolated from Thalassophryne nattereri venom in the therapy of Hypoxic Retinopathy in Zebrafish

Abstract

Zebrafish is a robust model for the study of eye diseases, surpassing murine models because it presents anatomical and functional similarities with human eye tissue. In addition, it presents rapid embryonic development, ease of genetic manipulation and retinal regeneration capacity. Hypoxic/Degenerative Retinopathies cause vision loss and therefore represent a serious problem in public health, and currently few treatments are effective. Retinopathies have as a common denominator pathological neovascularization, initiated by hypoxia that induces, among other factors, the production of endothelial vascular growth factor (VEGF). Thus, the discovery of new drugs with antiangiogenic and immunomodulatory potential is important. In this context, the unpublished peptide, called TnP isolated from thalassophryne nattereri venom, discovered and synthesized by the proponent research group, showed satisfactory therapeutic efficacy in Experimental Autoimmune Encephalomyelitis (EAE) in murine models, and among other mechanisms, had a pronounced inibiotory effect on the activity of matrix metalloproteinases (MMP), particularly in the MMP-9 isoform. Highlighting that this same enzyme accentuates the production of VEGF in pathological neovascularization. Having said that, we suggest in this study the evaluation of the pharmacological mechanisms of TnP in the therapy of Hypoxic Retinopathy. For this, we will induce pathological neovascularization through controlled and noninvasive hypoxia using nitrogen gas and pigmentary degeneration of the retina by prolonged light infraction. In the monitoring of angiogenesis we will use the mutant Zebrafish Tg (fli1:EGFP) and the therapeutic effect will be quantified initially by morphometric analysis of the retina. Finally, to monitor the expression and production of the factors involved VEGF, metalloproteinases, adherement molecules and the chemokines and cytokines involved in the process will be used the technique of in situ hybridization, real time PCR and mass spectrometry. We intend with these results to postulate the therapeutic use of TnP in Retinopathies and standardize the model of Hypoxic/Degenerative Retinopathy in Zebrafish. (AU)