Delivery Systems of Retinoprotective Proteins in the Retina

Abstract

Retinoprotective proteins play important roles for retinal tissue integrity. They can directly affect the function and the survival of photoreceptors, and/or indirectly target the retinal pigment epithelium (RPE) and endothelial cells that support these tissues. Retinoprotective proteins are used in basic, translational and in clinical studies to prevent and treat human retinal degenerative disorders. In this review, we provide an overview of proteins that protect the retina and focus on pigment epithelium-derived factor (PEDF), and its effects on photoreceptors, RPE cells, and endothelial cells. We also discuss delivery systems such as pharmacologic and genetic administration of proteins to achieve photoreceptor survival and retinal tissue integrity.

Sustained therapeutic effect of an anti-inflammatory peptide encapsulated in nanoparticles on ocular vascular leakage in diabetic retinopathy

“…There are three main systems of local administration of retina-protective proteins (Rebustini et al, 2021): 1), cell transplantation: the retina-protective proteins are delivered through the grafted cells in vitro via DNA expression vectors packaged into viral and non-viral carriers, to produce recombinant proteins. These infected or transfected cells, exemplified by RPE or induced pluripotent stem cells, are then injected into the retina; 2), gene delivery: the protein delivery is achieved with DNA expression vectors packaged into viral and non-viral carriers to prompt the expression of the proteins in the retina; 3), pharmacologic delivery: the purified recombinant proteins or synthetic peptides are packaged into different types of carriers (such as micro-particles/-emulsions or nanoparticles) and introduced into the vitreous.…”

Relevance of Peptide Homeostasis in Metabolic Retinal Degenerative Disorders: Curative Potential in Genetically Modified Mice

“…As a consequence, PEDF exerts its protective effects mainly on PRs. Our current knowledge on PEDF action has been reviewed by Rebustini et al (2021) . So far, several potential targets have been reported for the pathways involved in PEDF signaling, including MAPK activation, JAK/STAT, PI3K and additional pathways ( Pagan-Mercado and Becerra, 2019 ).…”

“…Other factors Abbreviation Source Receptor expression Main function 9 Brain-derived neurotrophic factor BDNF AC 1,2 , (GC) 1,2 , MC 3 (Bennett et al, 1999;Oku et al, 2002;Vecino et al, 2002;Avwenagha et al, 2006) TrkB PR 3 , AC 1,2 , GC 1,2 (Cellerino and Kohler, 1997;Vecino et al, 1998;Vecino et al, 2002) Neuron growth, differentation and survival, synaptogenesis 10 Pigment epithetlium derived factor PEDF RPE (Rebustini et al, 2021) PEDF-R RPE, PR (Rebustini et al, 2021) Neurothrophic, antiangiogenic, antitumorigenic 11 Vascular endothelial growth factor VEGF RPE 2 , PR 3 , HC 3 , BC 3 , AC 3 , (GC) 3 , MC 3 (Sall et al, 2004;Saint-Geniez et al, 2008) VEGFR1, VEGFR2, VEGFR3…”