Adiponectin Stimulates Angiogenesis in Developing Murine Retina

Abstract

Abstract: : Purpose: Adiponectin is an adipocyte–specific adipocytokine with anti–atherogenic and anti–diabetic properties, and its plasma levels are reduced in association with obesity–linked diseases. To date, little is understood whether adiponectin regulates retinal angiogenesis. Here, taking advantages of postnatal angiogenesis of murine retina, in which these consecutive processes during vascular development can be observed sequentially, we investigated whether adiponectin modulates the angiogenic process in vivo employing adiponectin knock–out mice (adipo –/–). Methods:Immunohistochemical analysis of murine developing retinal vasculature was performed to investigate the influences lacking for adiponectin as well as the normal development.For visualization of retinal vasculature, whole mount retinal preparations of different time points (postnatal day 1 to 21) were stained with mAb against PECAM–1 (platelet endothelial cell adhesion molecule) and PDGFR–ß (platelet–derived growth factor receptor). Mice of the same age served as controls. Results: Immunohistochemical staining of wholemount retinas during retinal vascularization demonstrated a significant delay in development and maturation of retinal vasculature in adipo –/– mice. A major delay in the outgrowth of the superficial retinal vessels towards the periphery was observed in adipo –/– mice. Adipo –/– retinas also exhibited a significant decrease in the density of filopodia sprouting from vascular endothelial cells and worse formation of a capillary network. Conclusions:Adiponectin might be essential for appropriate development of retinal vasculature and function to stimulate angiogenesis and vascular remodeling in developing murine retina.

Keywords: retinal development • retinal neovascularization • gene/expression